From af35468ccbada993c85aa8eb6881851220bb8847 Mon Sep 17 00:00:00 2001
From: Wei Liu <wei.liu2@citrix.com>
Date: Thu, 7 Jan 2016 18:42:20 +0000
Subject: [PATCH] 9pfs: rename virtio-9p.c to 9p.c

Now that file only contains generic code.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
(cherry picked from commit 60ce86c7140d5ca33d5fd87ce821681165d06b2a)
[BR: Fix and/or infrastructure for BSC#1020427 CVE-2016-9602]
Signed-off-by: Bruce Rogers <brogers@suse.com>
---
 hw/9pfs/9p.c          | 3269 +++++++++++++++++++++++++++++++++++++++++
 hw/9pfs/Makefile.objs |    2 +-
 hw/9pfs/virtio-9p.c   | 3269 -----------------------------------------
 3 files changed, 3270 insertions(+), 3270 deletions(-)

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
new file mode 100644
index 0000000000..800f01ead3
--- /dev/null
+++ b/hw/9pfs/9p.c
@@ -0,0 +1,3269 @@
+/*
+ * Virtio 9p backend
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "hw/virtio.h"
+#include "hw/pc.h"
+#include "qemu/sockets.h"
+#include "virtio-9p.h"
+#include "fsdev/qemu-fsdev.h"
+#include "9p-xattr.h"
+#include "virtio-9p-coth.h"
+#include "trace.h"
+#include "migration/migration.h"
+
+int open_fd_hw;
+int total_open_fd;
+static int open_fd_rc;
+
+enum {
+    Oread   = 0x00,
+    Owrite  = 0x01,
+    Ordwr   = 0x02,
+    Oexec   = 0x03,
+    Oexcl   = 0x04,
+    Otrunc  = 0x10,
+    Orexec  = 0x20,
+    Orclose = 0x40,
+    Oappend = 0x80,
+};
+
+ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
+{
+    ssize_t ret;
+    va_list ap;
+
+    va_start(ap, fmt);
+    ret = virtio_pdu_vmarshal(pdu, offset, fmt, ap);
+    va_end(ap);
+
+    return ret;
+}
+
+ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
+{
+    ssize_t ret;
+    va_list ap;
+
+    va_start(ap, fmt);
+    ret = virtio_pdu_vunmarshal(pdu, offset, fmt, ap);
+    va_end(ap);
+
+    return ret;
+}
+
+static void pdu_push_and_notify(V9fsPDU *pdu)
+{
+    virtio_9p_push_and_notify(pdu);
+}
+
+static int omode_to_uflags(int8_t mode)
+{
+    int ret = 0;
+
+    switch (mode & 3) {
+    case Oread:
+        ret = O_RDONLY;
+        break;
+    case Ordwr:
+        ret = O_RDWR;
+        break;
+    case Owrite:
+        ret = O_WRONLY;
+        break;
+    case Oexec:
+        ret = O_RDONLY;
+        break;
+    }
+
+    if (mode & Otrunc) {
+        ret |= O_TRUNC;
+    }
+
+    if (mode & Oappend) {
+        ret |= O_APPEND;
+    }
+
+    if (mode & Oexcl) {
+        ret |= O_EXCL;
+    }
+
+    return ret;
+}
+
+struct dotl_openflag_map {
+    int dotl_flag;
+    int open_flag;
+};
+
+static int dotl_to_open_flags(int flags)
+{
+    int i;
+    /*
+     * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
+     * and P9_DOTL_NOACCESS
+     */
+    int oflags = flags & O_ACCMODE;
+
+    struct dotl_openflag_map dotl_oflag_map[] = {
+        { P9_DOTL_CREATE, O_CREAT },
+        { P9_DOTL_EXCL, O_EXCL },
+        { P9_DOTL_NOCTTY , O_NOCTTY },
+        { P9_DOTL_TRUNC, O_TRUNC },
+        { P9_DOTL_APPEND, O_APPEND },
+        { P9_DOTL_NONBLOCK, O_NONBLOCK } ,
+        { P9_DOTL_DSYNC, O_DSYNC },
+        { P9_DOTL_FASYNC, FASYNC },
+        { P9_DOTL_DIRECT, O_DIRECT },
+        { P9_DOTL_LARGEFILE, O_LARGEFILE },
+        { P9_DOTL_DIRECTORY, O_DIRECTORY },
+        { P9_DOTL_NOFOLLOW, O_NOFOLLOW },
+        { P9_DOTL_NOATIME, O_NOATIME },
+        { P9_DOTL_SYNC, O_SYNC },
+    };
+
+    for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
+        if (flags & dotl_oflag_map[i].dotl_flag) {
+            oflags |= dotl_oflag_map[i].open_flag;
+        }
+    }
+
+    return oflags;
+}
+
+void cred_init(FsCred *credp)
+{
+    credp->fc_uid = -1;
+    credp->fc_gid = -1;
+    credp->fc_mode = -1;
+    credp->fc_rdev = -1;
+}
+
+static int get_dotl_openflags(V9fsState *s, int oflags)
+{
+    int flags;
+    /*
+     * Filter the client open flags
+     */
+    flags = dotl_to_open_flags(oflags);
+    flags &= ~(O_NOCTTY | O_ASYNC | O_CREAT);
+    /*
+     * Ignore direct disk access hint until the server supports it.
+     */
+    flags &= ~O_DIRECT;
+    return flags;
+}
+
+void v9fs_path_init(V9fsPath *path)
+{
+    path->data = NULL;
+    path->size = 0;
+}
+
+void v9fs_path_free(V9fsPath *path)
+{
+    g_free(path->data);
+    path->data = NULL;
+    path->size = 0;
+}
+
+void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs)
+{
+    v9fs_path_free(lhs);
+    lhs->data = g_malloc(rhs->size);
+    memcpy(lhs->data, rhs->data, rhs->size);
+    lhs->size = rhs->size;
+}
+
+int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
+                      const char *name, V9fsPath *path)
+{
+    int err;
+    err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
+    if (err < 0) {
+        err = -errno;
+    }
+    return err;
+}
+
+/*
+ * Return TRUE if s1 is an ancestor of s2.
+ *
+ * E.g. "a/b" is an ancestor of "a/b/c" but not of "a/bc/d".
+ * As a special case, We treat s1 as ancestor of s2 if they are same!
+ */
+static int v9fs_path_is_ancestor(V9fsPath *s1, V9fsPath *s2)
+{
+    if (!strncmp(s1->data, s2->data, s1->size - 1)) {
+        if (s2->data[s1->size - 1] == '\0' || s2->data[s1->size - 1] == '/') {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+static size_t v9fs_string_size(V9fsString *str)
+{
+    return str->size;
+}
+
+/*
+ * returns 0 if fid got re-opened, 1 if not, < 0 on error */
+static int v9fs_reopen_fid(V9fsPDU *pdu, V9fsFidState *f)
+{
+    int err = 1;
+    if (f->fid_type == P9_FID_FILE) {
+        if (f->fs.fd == -1) {
+            do {
+                err = v9fs_co_open(pdu, f, f->open_flags);
+            } while (err == -EINTR && !pdu->cancelled);
+        }
+    } else if (f->fid_type == P9_FID_DIR) {
+        if (f->fs.dir == NULL) {
+            do {
+                err = v9fs_co_opendir(pdu, f);
+            } while (err == -EINTR && !pdu->cancelled);
+        }
+    }
+    return err;
+}
+
+static V9fsFidState *get_fid(V9fsPDU *pdu, int32_t fid)
+{
+    int err;
+    V9fsFidState *f;
+    V9fsState *s = pdu->s;
+
+    for (f = s->fid_list; f; f = f->next) {
+        BUG_ON(f->clunked);
+        if (f->fid == fid) {
+            /*
+             * Update the fid ref upfront so that
+             * we don't get reclaimed when we yield
+             * in open later.
+             */
+            f->ref++;
+            /*
+             * check whether we need to reopen the
+             * file. We might have closed the fd
+             * while trying to free up some file
+             * descriptors.
+             */
+            err = v9fs_reopen_fid(pdu, f);
+            if (err < 0) {
+                f->ref--;
+                return NULL;
+            }
+            /*
+             * Mark the fid as referenced so that the LRU
+             * reclaim won't close the file descriptor
+             */
+            f->flags |= FID_REFERENCED;
+            return f;
+        }
+    }
+    return NULL;
+}
+
+static V9fsFidState *alloc_fid(V9fsState *s, int32_t fid)
+{
+    V9fsFidState *f;
+
+    for (f = s->fid_list; f; f = f->next) {
+        /* If fid is already there return NULL */
+        BUG_ON(f->clunked);
+        if (f->fid == fid) {
+            return NULL;
+        }
+    }
+    f = g_malloc0(sizeof(V9fsFidState));
+    f->fid = fid;
+    f->fid_type = P9_FID_NONE;
+    f->ref = 1;
+    /*
+     * Mark the fid as referenced so that the LRU
+     * reclaim won't close the file descriptor
+     */
+    f->flags |= FID_REFERENCED;
+    f->next = s->fid_list;
+    s->fid_list = f;
+
+    return f;
+}
+
+static int v9fs_xattr_fid_clunk(V9fsPDU *pdu, V9fsFidState *fidp)
+{
+    int retval = 0;
+
+    if (fidp->fs.xattr.copied_len == -1) {
+        /* getxattr/listxattr fid */
+        goto free_value;
+    }
+    /*
+     * if this is fid for setxattr. clunk should
+     * result in setxattr localcall
+     */
+    if (fidp->fs.xattr.len != fidp->fs.xattr.copied_len) {
+        /* clunk after partial write */
+        retval = -EINVAL;
+        goto free_out;
+    }
+    if (fidp->fs.xattr.len) {
+        retval = v9fs_co_lsetxattr(pdu, &fidp->path, &fidp->fs.xattr.name,
+                                   fidp->fs.xattr.value,
+                                   fidp->fs.xattr.len,
+                                   fidp->fs.xattr.flags);
+    } else {
+        retval = v9fs_co_lremovexattr(pdu, &fidp->path, &fidp->fs.xattr.name);
+    }
+free_out:
+    v9fs_string_free(&fidp->fs.xattr.name);
+free_value:
+    if (fidp->fs.xattr.value) {
+        g_free(fidp->fs.xattr.value);
+    }
+    return retval;
+}
+
+static int free_fid(V9fsPDU *pdu, V9fsFidState *fidp)
+{
+    int retval = 0;
+
+    if (fidp->fid_type == P9_FID_FILE) {
+        /* If we reclaimed the fd no need to close */
+        if (fidp->fs.fd != -1) {
+            retval = v9fs_co_close(pdu, &fidp->fs);
+        }
+    } else if (fidp->fid_type == P9_FID_DIR) {
+        if (fidp->fs.dir != NULL) {
+            retval = v9fs_co_closedir(pdu, &fidp->fs);
+        }
+    } else if (fidp->fid_type == P9_FID_XATTR) {
+        retval = v9fs_xattr_fid_clunk(pdu, fidp);
+    }
+    v9fs_path_free(&fidp->path);
+    g_free(fidp);
+    return retval;
+}
+
+static int put_fid(V9fsPDU *pdu, V9fsFidState *fidp)
+{
+    BUG_ON(!fidp->ref);
+    fidp->ref--;
+    /*
+     * Don't free the fid if it is in reclaim list
+     */
+    if (!fidp->ref && fidp->clunked) {
+        if (fidp->fid == pdu->s->root_fid) {
+            /*
+             * if the clunked fid is root fid then we
+             * have unmounted the fs on the client side.
+             * delete the migration blocker. Ideally, this
+             * should be hooked to transport close notification
+             */
+            if (pdu->s->migration_blocker) {
+                migrate_del_blocker(pdu->s->migration_blocker);
+                error_free(pdu->s->migration_blocker);
+                pdu->s->migration_blocker = NULL;
+            }
+        }
+        return free_fid(pdu, fidp);
+    }
+    return 0;
+}
+
+static V9fsFidState *clunk_fid(V9fsState *s, int32_t fid)
+{
+    V9fsFidState **fidpp, *fidp;
+
+    for (fidpp = &s->fid_list; *fidpp; fidpp = &(*fidpp)->next) {
+        if ((*fidpp)->fid == fid) {
+            break;
+        }
+    }
+    if (*fidpp == NULL) {
+        return NULL;
+    }
+    fidp = *fidpp;
+    *fidpp = fidp->next;
+    fidp->clunked = 1;
+    return fidp;
+}
+
+void v9fs_reclaim_fd(V9fsPDU *pdu)
+{
+    int reclaim_count = 0;
+    V9fsState *s = pdu->s;
+    V9fsFidState *f, *reclaim_list = NULL;
+
+    for (f = s->fid_list; f; f = f->next) {
+        /*
+         * Unlink fids cannot be reclaimed. Check
+         * for them and skip them. Also skip fids
+         * currently being operated on.
+         */
+        if (f->ref || f->flags & FID_NON_RECLAIMABLE) {
+            continue;
+        }
+        /*
+         * if it is a recently referenced fid
+         * we leave the fid untouched and clear the
+         * reference bit. We come back to it later
+         * in the next iteration. (a simple LRU without
+         * moving list elements around)
+         */
+        if (f->flags & FID_REFERENCED) {
+            f->flags &= ~FID_REFERENCED;
+            continue;
+        }
+        /*
+         * Add fids to reclaim list.
+         */
+        if (f->fid_type == P9_FID_FILE) {
+            if (f->fs.fd != -1) {
+                /*
+                 * Up the reference count so that
+                 * a clunk request won't free this fid
+                 */
+                f->ref++;
+                f->rclm_lst = reclaim_list;
+                reclaim_list = f;
+                f->fs_reclaim.fd = f->fs.fd;
+                f->fs.fd = -1;
+                reclaim_count++;
+            }
+        } else if (f->fid_type == P9_FID_DIR) {
+            if (f->fs.dir != NULL) {
+                /*
+                 * Up the reference count so that
+                 * a clunk request won't free this fid
+                 */
+                f->ref++;
+                f->rclm_lst = reclaim_list;
+                reclaim_list = f;
+                f->fs_reclaim.dir = f->fs.dir;
+                f->fs.dir = NULL;
+                reclaim_count++;
+            }
+        }
+        if (reclaim_count >= open_fd_rc) {
+            break;
+        }
+    }
+    /*
+     * Now close the fid in reclaim list. Free them if they
+     * are already clunked.
+     */
+    while (reclaim_list) {
+        f = reclaim_list;
+        reclaim_list = f->rclm_lst;
+        if (f->fid_type == P9_FID_FILE) {
+            v9fs_co_close(pdu, &f->fs_reclaim);
+        } else if (f->fid_type == P9_FID_DIR) {
+            v9fs_co_closedir(pdu, &f->fs_reclaim);
+        }
+        f->rclm_lst = NULL;
+        /*
+         * Now drop the fid reference, free it
+         * if clunked.
+         */
+        put_fid(pdu, f);
+    }
+}
+
+static int v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
+{
+    int err;
+    V9fsState *s = pdu->s;
+    V9fsFidState *fidp, head_fid;
+
+    head_fid.next = s->fid_list;
+    for (fidp = s->fid_list; fidp; fidp = fidp->next) {
+        if (fidp->path.size != path->size) {
+            continue;
+        }
+        if (!memcmp(fidp->path.data, path->data, path->size)) {
+            /* Mark the fid non reclaimable. */
+            fidp->flags |= FID_NON_RECLAIMABLE;
+
+            /* reopen the file/dir if already closed */
+            err = v9fs_reopen_fid(pdu, fidp);
+            if (err < 0) {
+                return -1;
+            }
+            /*
+             * Go back to head of fid list because
+             * the list could have got updated when
+             * switched to the worker thread
+             */
+            if (err == 0) {
+                fidp = &head_fid;
+            }
+        }
+    }
+    return 0;
+}
+
+static void virtfs_reset(V9fsPDU *pdu)
+{
+    V9fsState *s = pdu->s;
+    V9fsFidState *fidp = NULL;
+
+    /* Free all fids */
+    while (s->fid_list) {
+        fidp = s->fid_list;
+        s->fid_list = fidp->next;
+
+        if (fidp->ref) {
+            fidp->clunked = 1;
+        } else {
+            free_fid(pdu, fidp);
+        }
+    }
+    if (fidp) {
+        /* One or more unclunked fids found... */
+        error_report("9pfs:%s: One or more uncluncked fids "
+                     "found during reset", __func__);
+    }
+}
+
+#define P9_QID_TYPE_DIR         0x80
+#define P9_QID_TYPE_SYMLINK     0x02
+
+#define P9_STAT_MODE_DIR        0x80000000
+#define P9_STAT_MODE_APPEND     0x40000000
+#define P9_STAT_MODE_EXCL       0x20000000
+#define P9_STAT_MODE_MOUNT      0x10000000
+#define P9_STAT_MODE_AUTH       0x08000000
+#define P9_STAT_MODE_TMP        0x04000000
+#define P9_STAT_MODE_SYMLINK    0x02000000
+#define P9_STAT_MODE_LINK       0x01000000
+#define P9_STAT_MODE_DEVICE     0x00800000
+#define P9_STAT_MODE_NAMED_PIPE 0x00200000
+#define P9_STAT_MODE_SOCKET     0x00100000
+#define P9_STAT_MODE_SETUID     0x00080000
+#define P9_STAT_MODE_SETGID     0x00040000
+#define P9_STAT_MODE_SETVTX     0x00010000
+
+#define P9_STAT_MODE_TYPE_BITS (P9_STAT_MODE_DIR |          \
+                                P9_STAT_MODE_SYMLINK |      \
+                                P9_STAT_MODE_LINK |         \
+                                P9_STAT_MODE_DEVICE |       \
+                                P9_STAT_MODE_NAMED_PIPE |   \
+                                P9_STAT_MODE_SOCKET)
+
+/* This is the algorithm from ufs in spfs */
+static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
+{
+    size_t size;
+
+    memset(&qidp->path, 0, sizeof(qidp->path));
+    size = MIN(sizeof(stbuf->st_ino), sizeof(qidp->path));
+    memcpy(&qidp->path, &stbuf->st_ino, size);
+    qidp->version = stbuf->st_mtime ^ (stbuf->st_size << 8);
+    qidp->type = 0;
+    if (S_ISDIR(stbuf->st_mode)) {
+        qidp->type |= P9_QID_TYPE_DIR;
+    }
+    if (S_ISLNK(stbuf->st_mode)) {
+        qidp->type |= P9_QID_TYPE_SYMLINK;
+    }
+}
+
+static int fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp, V9fsQID *qidp)
+{
+    struct stat stbuf;
+    int err;
+
+    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (err < 0) {
+        return err;
+    }
+    stat_to_qid(&stbuf, qidp);
+    return 0;
+}
+
+V9fsPDU *pdu_alloc(V9fsState *s)
+{
+    V9fsPDU *pdu = NULL;
+
+    if (!QLIST_EMPTY(&s->free_list)) {
+        pdu = QLIST_FIRST(&s->free_list);
+        QLIST_REMOVE(pdu, next);
+        QLIST_INSERT_HEAD(&s->active_list, pdu, next);
+    }
+    return pdu;
+}
+
+void pdu_free(V9fsPDU *pdu)
+{
+    if (pdu) {
+        V9fsState *s = pdu->s;
+        /*
+         * Cancelled pdu are added back to the freelist
+         * by flush request .
+         */
+        if (!pdu->cancelled) {
+            QLIST_REMOVE(pdu, next);
+            QLIST_INSERT_HEAD(&s->free_list, pdu, next);
+        }
+    }
+}
+
+/*
+ * We don't do error checking for pdu_marshal/unmarshal here
+ * because we always expect to have enough space to encode
+ * error details
+ */
+static void pdu_complete(V9fsPDU *pdu, ssize_t len)
+{
+    int8_t id = pdu->id + 1; /* Response */
+    V9fsState *s = pdu->s;
+
+    if (len < 0) {
+        int err = -len;
+        len = 7;
+
+        if (s->proto_version != V9FS_PROTO_2000L) {
+            V9fsString str;
+
+            str.data = strerror(err);
+            str.size = strlen(str.data);
+
+            len += pdu_marshal(pdu, len, "s", &str);
+            id = P9_RERROR;
+        }
+
+        len += pdu_marshal(pdu, len, "d", err);
+
+        if (s->proto_version == V9FS_PROTO_2000L) {
+            id = P9_RLERROR;
+        }
+        trace_v9fs_rerror(pdu->tag, pdu->id, err); /* Trace ERROR */
+    }
+
+    /* fill out the header */
+    pdu_marshal(pdu, 0, "dbw", (int32_t)len, id, pdu->tag);
+
+    /* keep these in sync */
+    pdu->size = len;
+    pdu->id = id;
+
+    pdu_push_and_notify(pdu);
+
+    /* Now wakeup anybody waiting in flush for this request */
+    qemu_co_queue_next(&pdu->complete);
+
+    pdu_free(pdu);
+}
+
+static mode_t v9mode_to_mode(uint32_t mode, V9fsString *extension)
+{
+    mode_t ret;
+
+    ret = mode & 0777;
+    if (mode & P9_STAT_MODE_DIR) {
+        ret |= S_IFDIR;
+    }
+
+    if (mode & P9_STAT_MODE_SYMLINK) {
+        ret |= S_IFLNK;
+    }
+    if (mode & P9_STAT_MODE_SOCKET) {
+        ret |= S_IFSOCK;
+    }
+    if (mode & P9_STAT_MODE_NAMED_PIPE) {
+        ret |= S_IFIFO;
+    }
+    if (mode & P9_STAT_MODE_DEVICE) {
+        if (extension->size && extension->data[0] == 'c') {
+            ret |= S_IFCHR;
+        } else {
+            ret |= S_IFBLK;
+        }
+    }
+
+    if (!(ret&~0777)) {
+        ret |= S_IFREG;
+    }
+
+    if (mode & P9_STAT_MODE_SETUID) {
+        ret |= S_ISUID;
+    }
+    if (mode & P9_STAT_MODE_SETGID) {
+        ret |= S_ISGID;
+    }
+    if (mode & P9_STAT_MODE_SETVTX) {
+        ret |= S_ISVTX;
+    }
+
+    return ret;
+}
+
+static int donttouch_stat(V9fsStat *stat)
+{
+    if (stat->type == -1 &&
+        stat->dev == -1 &&
+        stat->qid.type == -1 &&
+        stat->qid.version == -1 &&
+        stat->qid.path == -1 &&
+        stat->mode == -1 &&
+        stat->atime == -1 &&
+        stat->mtime == -1 &&
+        stat->length == -1 &&
+        !stat->name.size &&
+        !stat->uid.size &&
+        !stat->gid.size &&
+        !stat->muid.size &&
+        stat->n_uid == -1 &&
+        stat->n_gid == -1 &&
+        stat->n_muid == -1) {
+        return 1;
+    }
+
+    return 0;
+}
+
+static void v9fs_stat_init(V9fsStat *stat)
+{
+    v9fs_string_init(&stat->name);
+    v9fs_string_init(&stat->uid);
+    v9fs_string_init(&stat->gid);
+    v9fs_string_init(&stat->muid);
+    v9fs_string_init(&stat->extension);
+}
+
+static void v9fs_stat_free(V9fsStat *stat)
+{
+    v9fs_string_free(&stat->name);
+    v9fs_string_free(&stat->uid);
+    v9fs_string_free(&stat->gid);
+    v9fs_string_free(&stat->muid);
+    v9fs_string_free(&stat->extension);
+}
+
+static uint32_t stat_to_v9mode(const struct stat *stbuf)
+{
+    uint32_t mode;
+
+    mode = stbuf->st_mode & 0777;
+    if (S_ISDIR(stbuf->st_mode)) {
+        mode |= P9_STAT_MODE_DIR;
+    }
+
+    if (S_ISLNK(stbuf->st_mode)) {
+        mode |= P9_STAT_MODE_SYMLINK;
+    }
+
+    if (S_ISSOCK(stbuf->st_mode)) {
+        mode |= P9_STAT_MODE_SOCKET;
+    }
+
+    if (S_ISFIFO(stbuf->st_mode)) {
+        mode |= P9_STAT_MODE_NAMED_PIPE;
+    }
+
+    if (S_ISBLK(stbuf->st_mode) || S_ISCHR(stbuf->st_mode)) {
+        mode |= P9_STAT_MODE_DEVICE;
+    }
+
+    if (stbuf->st_mode & S_ISUID) {
+        mode |= P9_STAT_MODE_SETUID;
+    }
+
+    if (stbuf->st_mode & S_ISGID) {
+        mode |= P9_STAT_MODE_SETGID;
+    }
+
+    if (stbuf->st_mode & S_ISVTX) {
+        mode |= P9_STAT_MODE_SETVTX;
+    }
+
+    return mode;
+}
+
+static int stat_to_v9stat(V9fsPDU *pdu, V9fsPath *name,
+                            const struct stat *stbuf,
+                            V9fsStat *v9stat)
+{
+    int err;
+    const char *str;
+
+    memset(v9stat, 0, sizeof(*v9stat));
+
+    stat_to_qid(stbuf, &v9stat->qid);
+    v9stat->mode = stat_to_v9mode(stbuf);
+    v9stat->atime = stbuf->st_atime;
+    v9stat->mtime = stbuf->st_mtime;
+    v9stat->length = stbuf->st_size;
+
+    v9fs_string_null(&v9stat->uid);
+    v9fs_string_null(&v9stat->gid);
+    v9fs_string_null(&v9stat->muid);
+
+    v9stat->n_uid = stbuf->st_uid;
+    v9stat->n_gid = stbuf->st_gid;
+    v9stat->n_muid = 0;
+
+    v9fs_string_null(&v9stat->extension);
+
+    if (v9stat->mode & P9_STAT_MODE_SYMLINK) {
+        err = v9fs_co_readlink(pdu, name, &v9stat->extension);
+        if (err < 0) {
+            return err;
+        }
+    } else if (v9stat->mode & P9_STAT_MODE_DEVICE) {
+        v9fs_string_sprintf(&v9stat->extension, "%c %u %u",
+                S_ISCHR(stbuf->st_mode) ? 'c' : 'b',
+                major(stbuf->st_rdev), minor(stbuf->st_rdev));
+    } else if (S_ISDIR(stbuf->st_mode) || S_ISREG(stbuf->st_mode)) {
+        v9fs_string_sprintf(&v9stat->extension, "%s %lu",
+                "HARDLINKCOUNT", (unsigned long)stbuf->st_nlink);
+    }
+
+    str = strrchr(name->data, '/');
+    if (str) {
+        str += 1;
+    } else {
+        str = name->data;
+    }
+
+    v9fs_string_sprintf(&v9stat->name, "%s", str);
+
+    v9stat->size = 61 +
+        v9fs_string_size(&v9stat->name) +
+        v9fs_string_size(&v9stat->uid) +
+        v9fs_string_size(&v9stat->gid) +
+        v9fs_string_size(&v9stat->muid) +
+        v9fs_string_size(&v9stat->extension);
+    return 0;
+}
+
+#define P9_STATS_MODE          0x00000001ULL
+#define P9_STATS_NLINK         0x00000002ULL
+#define P9_STATS_UID           0x00000004ULL
+#define P9_STATS_GID           0x00000008ULL
+#define P9_STATS_RDEV          0x00000010ULL
+#define P9_STATS_ATIME         0x00000020ULL
+#define P9_STATS_MTIME         0x00000040ULL
+#define P9_STATS_CTIME         0x00000080ULL
+#define P9_STATS_INO           0x00000100ULL
+#define P9_STATS_SIZE          0x00000200ULL
+#define P9_STATS_BLOCKS        0x00000400ULL
+
+#define P9_STATS_BTIME         0x00000800ULL
+#define P9_STATS_GEN           0x00001000ULL
+#define P9_STATS_DATA_VERSION  0x00002000ULL
+
+#define P9_STATS_BASIC         0x000007ffULL /* Mask for fields up to BLOCKS */
+#define P9_STATS_ALL           0x00003fffULL /* Mask for All fields above */
+
+
+static void stat_to_v9stat_dotl(V9fsState *s, const struct stat *stbuf,
+                                V9fsStatDotl *v9lstat)
+{
+    memset(v9lstat, 0, sizeof(*v9lstat));
+
+    v9lstat->st_mode = stbuf->st_mode;
+    v9lstat->st_nlink = stbuf->st_nlink;
+    v9lstat->st_uid = stbuf->st_uid;
+    v9lstat->st_gid = stbuf->st_gid;
+    v9lstat->st_rdev = stbuf->st_rdev;
+    v9lstat->st_size = stbuf->st_size;
+    v9lstat->st_blksize = stbuf->st_blksize;
+    v9lstat->st_blocks = stbuf->st_blocks;
+    v9lstat->st_atime_sec = stbuf->st_atime;
+    v9lstat->st_atime_nsec = stbuf->st_atim.tv_nsec;
+    v9lstat->st_mtime_sec = stbuf->st_mtime;
+    v9lstat->st_mtime_nsec = stbuf->st_mtim.tv_nsec;
+    v9lstat->st_ctime_sec = stbuf->st_ctime;
+    v9lstat->st_ctime_nsec = stbuf->st_ctim.tv_nsec;
+    /* Currently we only support BASIC fields in stat */
+    v9lstat->st_result_mask = P9_STATS_BASIC;
+
+    stat_to_qid(stbuf, &v9lstat->qid);
+}
+
+static void print_sg(struct iovec *sg, int cnt)
+{
+    int i;
+
+    printf("sg[%d]: {", cnt);
+    for (i = 0; i < cnt; i++) {
+        if (i) {
+            printf(", ");
+        }
+        printf("(%p, %zd)", sg[i].iov_base, sg[i].iov_len);
+    }
+    printf("}\n");
+}
+
+/* Will call this only for path name based fid */
+static void v9fs_fix_path(V9fsPath *dst, V9fsPath *src, int len)
+{
+    V9fsPath str;
+    v9fs_path_init(&str);
+    v9fs_path_copy(&str, dst);
+    v9fs_string_sprintf((V9fsString *)dst, "%s%s", src->data, str.data+len);
+    v9fs_path_free(&str);
+    /* +1 to include terminating NULL */
+    dst->size++;
+}
+
+static inline bool is_ro_export(FsContext *ctx)
+{
+    return ctx->export_flags & V9FS_RDONLY;
+}
+
+static void v9fs_version(void *opaque)
+{
+    ssize_t err;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+    V9fsString version;
+    size_t offset = 7;
+
+    v9fs_string_init(&version);
+    err = pdu_unmarshal(pdu, offset, "ds", &s->msize, &version);
+    if (err < 0) {
+        offset = err;
+        goto out;
+    }
+    trace_v9fs_version(pdu->tag, pdu->id, s->msize, version.data);
+
+    virtfs_reset(pdu);
+
+    if (!strcmp(version.data, "9P2000.u")) {
+        s->proto_version = V9FS_PROTO_2000U;
+    } else if (!strcmp(version.data, "9P2000.L")) {
+        s->proto_version = V9FS_PROTO_2000L;
+    } else {
+        v9fs_string_sprintf(&version, "unknown");
+    }
+
+    err = pdu_marshal(pdu, offset, "ds", s->msize, &version);
+    if (err < 0) {
+        offset = err;
+        goto out;
+    }
+    offset += err;
+    trace_v9fs_version_return(pdu->tag, pdu->id, s->msize, version.data);
+out:
+    pdu_complete(pdu, offset);
+    v9fs_string_free(&version);
+}
+
+static void v9fs_attach(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+    int32_t fid, afid, n_uname;
+    V9fsString uname, aname;
+    V9fsFidState *fidp;
+    size_t offset = 7;
+    V9fsQID qid;
+    ssize_t err;
+
+    v9fs_string_init(&uname);
+    v9fs_string_init(&aname);
+    err = pdu_unmarshal(pdu, offset, "ddssd", &fid,
+                        &afid, &uname, &aname, &n_uname);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_attach(pdu->tag, pdu->id, fid, afid, uname.data, aname.data);
+
+    fidp = alloc_fid(s, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    fidp->uid = n_uname;
+    err = v9fs_co_name_to_path(pdu, NULL, "/", &fidp->path);
+    if (err < 0) {
+        err = -EINVAL;
+        clunk_fid(s, fid);
+        goto out;
+    }
+    err = fid_to_qid(pdu, fidp, &qid);
+    if (err < 0) {
+        err = -EINVAL;
+        clunk_fid(s, fid);
+        goto out;
+    }
+    err = pdu_marshal(pdu, offset, "Q", &qid);
+    if (err < 0) {
+        clunk_fid(s, fid);
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_attach_return(pdu->tag, pdu->id,
+                             qid.type, qid.version, qid.path);
+    /*
+     * disable migration if we haven't done already.
+     * attach could get called multiple times for the same export.
+     */
+    if (!s->migration_blocker) {
+        s->root_fid = fid;
+        error_set(&s->migration_blocker, QERR_VIRTFS_FEATURE_BLOCKS_MIGRATION,
+                  s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
+        migrate_add_blocker(s->migration_blocker);
+    }
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&uname);
+    v9fs_string_free(&aname);
+}
+
+static void v9fs_stat(void *opaque)
+{
+    int32_t fid;
+    V9fsStat v9stat;
+    ssize_t err = 0;
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+
+    err = pdu_unmarshal(pdu, offset, "d", &fid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_stat(pdu->tag, pdu->id, fid);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    err = stat_to_v9stat(pdu, &fidp->path, &stbuf, &v9stat);
+    if (err < 0) {
+        goto out;
+    }
+    err = pdu_marshal(pdu, offset, "wS", 0, &v9stat);
+    if (err < 0) {
+        v9fs_stat_free(&v9stat);
+        goto out;
+    }
+    trace_v9fs_stat_return(pdu->tag, pdu->id, v9stat.mode,
+                           v9stat.atime, v9stat.mtime, v9stat.length);
+    err += offset;
+    v9fs_stat_free(&v9stat);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static void v9fs_getattr(void *opaque)
+{
+    int32_t fid;
+    size_t offset = 7;
+    ssize_t retval = 0;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    uint64_t request_mask;
+    V9fsStatDotl v9stat_dotl;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    retval = pdu_unmarshal(pdu, offset, "dq", &fid, &request_mask);
+    if (retval < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_getattr(pdu->tag, pdu->id, fid, request_mask);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        retval = -ENOENT;
+        goto out_nofid;
+    }
+    /*
+     * Currently we only support BASIC fields in stat, so there is no
+     * need to look at request_mask.
+     */
+    retval = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (retval < 0) {
+        goto out;
+    }
+    stat_to_v9stat_dotl(s, &stbuf, &v9stat_dotl);
+
+    /*  fill st_gen if requested and supported by underlying fs */
+    if (request_mask & P9_STATS_GEN) {
+        retval = v9fs_co_st_gen(pdu, &fidp->path, stbuf.st_mode, &v9stat_dotl);
+        if (retval < 0) {
+            goto out;
+        }
+        v9stat_dotl.st_result_mask |= P9_STATS_GEN;
+    }
+    retval = pdu_marshal(pdu, offset, "A", &v9stat_dotl);
+    if (retval < 0) {
+        goto out;
+    }
+    retval += offset;
+    trace_v9fs_getattr_return(pdu->tag, pdu->id, v9stat_dotl.st_result_mask,
+                              v9stat_dotl.st_mode, v9stat_dotl.st_uid,
+                              v9stat_dotl.st_gid);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, retval);
+}
+
+/* Attribute flags */
+#define P9_ATTR_MODE       (1 << 0)
+#define P9_ATTR_UID        (1 << 1)
+#define P9_ATTR_GID        (1 << 2)
+#define P9_ATTR_SIZE       (1 << 3)
+#define P9_ATTR_ATIME      (1 << 4)
+#define P9_ATTR_MTIME      (1 << 5)
+#define P9_ATTR_CTIME      (1 << 6)
+#define P9_ATTR_ATIME_SET  (1 << 7)
+#define P9_ATTR_MTIME_SET  (1 << 8)
+
+#define P9_ATTR_MASK    127
+
+static void v9fs_setattr(void *opaque)
+{
+    int err = 0;
+    int32_t fid;
+    V9fsFidState *fidp;
+    size_t offset = 7;
+    V9fsIattr v9iattr;
+    V9fsPDU *pdu = opaque;
+
+    err = pdu_unmarshal(pdu, offset, "dI", &fid, &v9iattr);
+    if (err < 0) {
+        goto out_nofid;
+    }
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (v9iattr.valid & P9_ATTR_MODE) {
+        err = v9fs_co_chmod(pdu, &fidp->path, v9iattr.mode);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9iattr.valid & (P9_ATTR_ATIME | P9_ATTR_MTIME)) {
+        struct timespec times[2];
+        if (v9iattr.valid & P9_ATTR_ATIME) {
+            if (v9iattr.valid & P9_ATTR_ATIME_SET) {
+                times[0].tv_sec = v9iattr.atime_sec;
+                times[0].tv_nsec = v9iattr.atime_nsec;
+            } else {
+                times[0].tv_nsec = UTIME_NOW;
+            }
+        } else {
+            times[0].tv_nsec = UTIME_OMIT;
+        }
+        if (v9iattr.valid & P9_ATTR_MTIME) {
+            if (v9iattr.valid & P9_ATTR_MTIME_SET) {
+                times[1].tv_sec = v9iattr.mtime_sec;
+                times[1].tv_nsec = v9iattr.mtime_nsec;
+            } else {
+                times[1].tv_nsec = UTIME_NOW;
+            }
+        } else {
+            times[1].tv_nsec = UTIME_OMIT;
+        }
+        err = v9fs_co_utimensat(pdu, &fidp->path, times);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    /*
+     * If the only valid entry in iattr is ctime we can call
+     * chown(-1,-1) to update the ctime of the file
+     */
+    if ((v9iattr.valid & (P9_ATTR_UID | P9_ATTR_GID)) ||
+        ((v9iattr.valid & P9_ATTR_CTIME)
+         && !((v9iattr.valid & P9_ATTR_MASK) & ~P9_ATTR_CTIME))) {
+        if (!(v9iattr.valid & P9_ATTR_UID)) {
+            v9iattr.uid = -1;
+        }
+        if (!(v9iattr.valid & P9_ATTR_GID)) {
+            v9iattr.gid = -1;
+        }
+        err = v9fs_co_chown(pdu, &fidp->path, v9iattr.uid,
+                            v9iattr.gid);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9iattr.valid & (P9_ATTR_SIZE)) {
+        err = v9fs_co_truncate(pdu, &fidp->path, v9iattr.size);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    err = offset;
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static int v9fs_walk_marshal(V9fsPDU *pdu, uint16_t nwnames, V9fsQID *qids)
+{
+    int i;
+    ssize_t err;
+    size_t offset = 7;
+
+    err = pdu_marshal(pdu, offset, "w", nwnames);
+    if (err < 0) {
+        return err;
+    }
+    offset += err;
+    for (i = 0; i < nwnames; i++) {
+        err = pdu_marshal(pdu, offset, "Q", &qids[i]);
+        if (err < 0) {
+            return err;
+        }
+        offset += err;
+    }
+    return offset;
+}
+
+static void v9fs_walk(void *opaque)
+{
+    int name_idx;
+    V9fsQID *qids = NULL;
+    int i, err = 0;
+    V9fsPath dpath, path;
+    uint16_t nwnames;
+    struct stat stbuf;
+    size_t offset = 7;
+    int32_t fid, newfid;
+    V9fsString *wnames = NULL;
+    V9fsFidState *fidp;
+    V9fsFidState *newfidp = NULL;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    err = pdu_unmarshal(pdu, offset, "ddw", &fid, &newfid, &nwnames);
+    if (err < 0) {
+        pdu_complete(pdu, err);
+        return ;
+    }
+    offset += err;
+
+    trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames);
+
+    if (nwnames && nwnames <= P9_MAXWELEM) {
+        wnames = g_malloc0(sizeof(wnames[0]) * nwnames);
+        qids   = g_malloc0(sizeof(qids[0]) * nwnames);
+        for (i = 0; i < nwnames; i++) {
+            err = pdu_unmarshal(pdu, offset, "s", &wnames[i]);
+            if (err < 0) {
+                goto out_nofid;
+            }
+            offset += err;
+        }
+    } else if (nwnames > P9_MAXWELEM) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    v9fs_path_init(&dpath);
+    v9fs_path_init(&path);
+    /*
+     * Both dpath and path initially poin to fidp.
+     * Needed to handle request with nwnames == 0
+     */
+    v9fs_path_copy(&dpath, &fidp->path);
+    v9fs_path_copy(&path, &fidp->path);
+    for (name_idx = 0; name_idx < nwnames; name_idx++) {
+        err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_lstat(pdu, &path, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        stat_to_qid(&stbuf, &qids[name_idx]);
+        v9fs_path_copy(&dpath, &path);
+    }
+    if (fid == newfid) {
+        BUG_ON(fidp->fid_type != P9_FID_NONE);
+        v9fs_path_copy(&fidp->path, &path);
+    } else {
+        newfidp = alloc_fid(s, newfid);
+        if (newfidp == NULL) {
+            err = -EINVAL;
+            goto out;
+        }
+        newfidp->uid = fidp->uid;
+        v9fs_path_copy(&newfidp->path, &path);
+    }
+    err = v9fs_walk_marshal(pdu, nwnames, qids);
+    trace_v9fs_walk_return(pdu->tag, pdu->id, nwnames, qids);
+out:
+    put_fid(pdu, fidp);
+    if (newfidp) {
+        put_fid(pdu, newfidp);
+    }
+    v9fs_path_free(&dpath);
+    v9fs_path_free(&path);
+out_nofid:
+    pdu_complete(pdu, err);
+    if (nwnames && nwnames <= P9_MAXWELEM) {
+        for (name_idx = 0; name_idx < nwnames; name_idx++) {
+            v9fs_string_free(&wnames[name_idx]);
+        }
+        g_free(wnames);
+        g_free(qids);
+    }
+}
+
+static int32_t get_iounit(V9fsPDU *pdu, V9fsPath *path)
+{
+    struct statfs stbuf;
+    int32_t iounit = 0;
+    V9fsState *s = pdu->s;
+
+    /*
+     * iounit should be multiples of f_bsize (host filesystem block size
+     * and as well as less than (client msize - P9_IOHDRSZ))
+     */
+    if (!v9fs_co_statfs(pdu, path, &stbuf)) {
+        iounit = stbuf.f_bsize;
+        iounit *= (s->msize - P9_IOHDRSZ)/stbuf.f_bsize;
+    }
+    if (!iounit) {
+        iounit = s->msize - P9_IOHDRSZ;
+    }
+    return iounit;
+}
+
+static void v9fs_open(void *opaque)
+{
+    int flags;
+    int32_t fid;
+    int32_t mode;
+    V9fsQID qid;
+    int iounit = 0;
+    ssize_t err = 0;
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    if (s->proto_version == V9FS_PROTO_2000L) {
+        err = pdu_unmarshal(pdu, offset, "dd", &fid, &mode);
+    } else {
+        uint8_t modebyte;
+        err = pdu_unmarshal(pdu, offset, "db", &fid, &modebyte);
+        mode = modebyte;
+    }
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_open(pdu->tag, pdu->id, fid, mode);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    BUG_ON(fidp->fid_type != P9_FID_NONE);
+
+    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    stat_to_qid(&stbuf, &qid);
+    if (S_ISDIR(stbuf.st_mode)) {
+        err = v9fs_co_opendir(pdu, fidp);
+        if (err < 0) {
+            goto out;
+        }
+        fidp->fid_type = P9_FID_DIR;
+        err = pdu_marshal(pdu, offset, "Qd", &qid, 0);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset;
+    } else {
+        if (s->proto_version == V9FS_PROTO_2000L) {
+            flags = get_dotl_openflags(s, mode);
+        } else {
+            flags = omode_to_uflags(mode);
+        }
+        if (is_ro_export(&s->ctx)) {
+            if (mode & O_WRONLY || mode & O_RDWR ||
+                mode & O_APPEND || mode & O_TRUNC) {
+                err = -EROFS;
+                goto out;
+            }
+        }
+        err = v9fs_co_open(pdu, fidp, flags);
+        if (err < 0) {
+            goto out;
+        }
+        fidp->fid_type = P9_FID_FILE;
+        fidp->open_flags = flags;
+        if (flags & O_EXCL) {
+            /*
+             * We let the host file system do O_EXCL check
+             * We should not reclaim such fd
+             */
+            fidp->flags |= FID_NON_RECLAIMABLE;
+        }
+        iounit = get_iounit(pdu, &fidp->path);
+        err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset;
+    }
+    trace_v9fs_open_return(pdu->tag, pdu->id,
+                           qid.type, qid.version, qid.path, iounit);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static void v9fs_lcreate(void *opaque)
+{
+    int32_t dfid, flags, mode;
+    gid_t gid;
+    ssize_t err = 0;
+    ssize_t offset = 7;
+    V9fsString name;
+    V9fsFidState *fidp;
+    struct stat stbuf;
+    V9fsQID qid;
+    int32_t iounit;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dsddd", &dfid,
+                        &name, &flags, &mode, &gid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_lcreate(pdu->tag, pdu->id, dfid, flags, mode, gid);
+
+    fidp = get_fid(pdu, dfid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    flags = get_dotl_openflags(pdu->s, flags);
+    err = v9fs_co_open2(pdu, fidp, &name, gid,
+                        flags | O_CREAT, mode, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    fidp->fid_type = P9_FID_FILE;
+    fidp->open_flags = flags;
+    if (flags & O_EXCL) {
+        /*
+         * We let the host file system do O_EXCL check
+         * We should not reclaim such fd
+         */
+        fidp->flags |= FID_NON_RECLAIMABLE;
+    }
+    iounit =  get_iounit(pdu, &fidp->path);
+    stat_to_qid(&stbuf, &qid);
+    err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_lcreate_return(pdu->tag, pdu->id,
+                              qid.type, qid.version, qid.path, iounit);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void v9fs_fsync(void *opaque)
+{
+    int err;
+    int32_t fid;
+    int datasync;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+
+    err = pdu_unmarshal(pdu, offset, "dd", &fid, &datasync);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_fsync(pdu->tag, pdu->id, fid, datasync);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_fsync(pdu, fidp, datasync);
+    if (!err) {
+        err = offset;
+    }
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static void v9fs_clunk(void *opaque)
+{
+    int err;
+    int32_t fid;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    err = pdu_unmarshal(pdu, offset, "d", &fid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_clunk(pdu->tag, pdu->id, fid);
+
+    fidp = clunk_fid(s, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    /*
+     * Bump the ref so that put_fid will
+     * free the fid.
+     */
+    fidp->ref++;
+    err = put_fid(pdu, fidp);
+    if (!err) {
+        err = offset;
+    }
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
+                           uint64_t off, uint32_t max_count)
+{
+    ssize_t err;
+    size_t offset = 7;
+    int read_count;
+    int64_t xattr_len;
+
+    xattr_len = fidp->fs.xattr.len;
+    read_count = xattr_len - off;
+    if (read_count > max_count) {
+        read_count = max_count;
+    } else if (read_count < 0) {
+        /*
+         * read beyond XATTR value
+         */
+        read_count = 0;
+    }
+    err = pdu_marshal(pdu, offset, "d", read_count);
+    if (err < 0) {
+        return err;
+    }
+    offset += err;
+    err = v9fs_pack(pdu->elem.in_sg, pdu->elem.in_num, offset,
+                    ((char *)fidp->fs.xattr.value) + off,
+                    read_count);
+    if (err < 0) {
+        return err;
+    }
+    offset += err;
+    return offset;
+}
+
+static int v9fs_do_readdir_with_stat(V9fsPDU *pdu,
+                                     V9fsFidState *fidp, uint32_t max_count)
+{
+    V9fsPath path;
+    V9fsStat v9stat;
+    int len, err = 0;
+    int32_t count = 0;
+    struct stat stbuf;
+    off_t saved_dir_pos;
+    struct dirent *dent, *result;
+
+    /* save the directory position */
+    saved_dir_pos = v9fs_co_telldir(pdu, fidp);
+    if (saved_dir_pos < 0) {
+        return saved_dir_pos;
+    }
+
+    dent = g_malloc(sizeof(struct dirent));
+
+    while (1) {
+        v9fs_path_init(&path);
+        err = v9fs_co_readdir_r(pdu, fidp, dent, &result);
+        if (err || !result) {
+            break;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, dent->d_name, &path);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_lstat(pdu, &path, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = stat_to_v9stat(pdu, &path, &stbuf, &v9stat);
+        if (err < 0) {
+            goto out;
+        }
+        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
+        len = pdu_marshal(pdu, 11 + count, "S", &v9stat);
+        if ((len != (v9stat.size + 2)) || ((count + len) > max_count)) {
+            /* Ran out of buffer. Set dir back to old position and return */
+            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
+            v9fs_stat_free(&v9stat);
+            v9fs_path_free(&path);
+            g_free(dent);
+            return count;
+        }
+        count += len;
+        v9fs_stat_free(&v9stat);
+        v9fs_path_free(&path);
+        saved_dir_pos = dent->d_off;
+    }
+out:
+    g_free(dent);
+    v9fs_path_free(&path);
+    if (err < 0) {
+        return err;
+    }
+    return count;
+}
+
+/*
+ * Create a QEMUIOVector for a sub-region of PDU iovecs
+ *
+ * @qiov:       uninitialized QEMUIOVector
+ * @skip:       number of bytes to skip from beginning of PDU
+ * @size:       number of bytes to include
+ * @is_write:   true - write, false - read
+ *
+ * The resulting QEMUIOVector has heap-allocated iovecs and must be cleaned up
+ * with qemu_iovec_destroy().
+ */
+static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
+                                    size_t skip, size_t size,
+                                    bool is_write)
+{
+    QEMUIOVector elem;
+    struct iovec *iov;
+    unsigned int niov;
+
+    virtio_init_iov_from_pdu(pdu, &iov, &niov, is_write);
+
+    qemu_iovec_init_external(&elem, iov, niov);
+    qemu_iovec_init(qiov, niov);
+    qemu_iovec_concat(qiov, &elem, skip, size);
+}
+
+static void v9fs_read(void *opaque)
+{
+    int32_t fid;
+    uint64_t off;
+    ssize_t err = 0;
+    int32_t count = 0;
+    size_t offset = 7;
+    uint32_t max_count;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    err = pdu_unmarshal(pdu, offset, "dqd", &fid, &off, &max_count);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_read(pdu->tag, pdu->id, fid, off, max_count);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (fidp->fid_type == P9_FID_DIR) {
+
+        if (off == 0) {
+            v9fs_co_rewinddir(pdu, fidp);
+        }
+        count = v9fs_do_readdir_with_stat(pdu, fidp, max_count);
+        if (count < 0) {
+            err = count;
+            goto out;
+        }
+        err = pdu_marshal(pdu, offset, "d", count);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset + count;
+    } else if (fidp->fid_type == P9_FID_FILE) {
+        QEMUIOVector qiov_full;
+        QEMUIOVector qiov;
+        int32_t len;
+
+        v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset + 4, max_count, false);
+        qemu_iovec_init(&qiov, qiov_full.niov);
+        do {
+            qemu_iovec_reset(&qiov);
+            qemu_iovec_concat(&qiov, &qiov_full, count, qiov_full.size - count);
+            if (0) {
+                print_sg(qiov.iov, qiov.niov);
+            }
+            /* Loop in case of EINTR */
+            do {
+                len = v9fs_co_preadv(pdu, fidp, qiov.iov, qiov.niov, off);
+                if (len >= 0) {
+                    off   += len;
+                    count += len;
+                }
+            } while (len == -EINTR && !pdu->cancelled);
+            if (len < 0) {
+                /* IO error return the error */
+                err = len;
+                goto out;
+            }
+        } while (count < max_count && len > 0);
+        err = pdu_marshal(pdu, offset, "d", count);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset + count;
+        qemu_iovec_destroy(&qiov);
+        qemu_iovec_destroy(&qiov_full);
+    } else if (fidp->fid_type == P9_FID_XATTR) {
+        err = v9fs_xattr_read(s, pdu, fidp, off, max_count);
+    } else {
+        err = -EINVAL;
+    }
+    trace_v9fs_read_return(pdu->tag, pdu->id, count, err);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static size_t v9fs_readdir_data_size(V9fsString *name)
+{
+    /*
+     * Size of each dirent on the wire: size of qid (13) + size of offset (8)
+     * size of type (1) + size of name.size (2) + strlen(name.data)
+     */
+    return 24 + v9fs_string_size(name);
+}
+
+static int v9fs_do_readdir(V9fsPDU *pdu,
+                           V9fsFidState *fidp, int32_t max_count)
+{
+    size_t size;
+    V9fsQID qid;
+    V9fsString name;
+    int len, err = 0;
+    int32_t count = 0;
+    off_t saved_dir_pos;
+    struct dirent *dent, *result;
+
+    /* save the directory position */
+    saved_dir_pos = v9fs_co_telldir(pdu, fidp);
+    if (saved_dir_pos < 0) {
+        return saved_dir_pos;
+    }
+
+    dent = g_malloc(sizeof(struct dirent));
+
+    while (1) {
+        err = v9fs_co_readdir_r(pdu, fidp, dent, &result);
+        if (err || !result) {
+            break;
+        }
+        v9fs_string_init(&name);
+        v9fs_string_sprintf(&name, "%s", dent->d_name);
+        if ((count + v9fs_readdir_data_size(&name)) > max_count) {
+            /* Ran out of buffer. Set dir back to old position and return */
+            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
+            v9fs_string_free(&name);
+            g_free(dent);
+            return count;
+        }
+        /*
+         * Fill up just the path field of qid because the client uses
+         * only that. To fill the entire qid structure we will have
+         * to stat each dirent found, which is expensive
+         */
+        size = MIN(sizeof(dent->d_ino), sizeof(qid.path));
+        memcpy(&qid.path, &dent->d_ino, size);
+        /* Fill the other fields with dummy values */
+        qid.type = 0;
+        qid.version = 0;
+
+        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
+        len = pdu_marshal(pdu, 11 + count, "Qqbs",
+                          &qid, dent->d_off,
+                          dent->d_type, &name);
+        if (len < 0) {
+            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
+            v9fs_string_free(&name);
+            g_free(dent);
+            return len;
+        }
+        count += len;
+        v9fs_string_free(&name);
+        saved_dir_pos = dent->d_off;
+    }
+    g_free(dent);
+    if (err < 0) {
+        return err;
+    }
+    return count;
+}
+
+static void v9fs_readdir(void *opaque)
+{
+    int32_t fid;
+    V9fsFidState *fidp;
+    ssize_t retval = 0;
+    size_t offset = 7;
+    uint64_t initial_offset;
+    int32_t count;
+    uint32_t max_count;
+    V9fsPDU *pdu = opaque;
+
+    retval = pdu_unmarshal(pdu, offset, "dqd", &fid,
+                           &initial_offset, &max_count);
+    if (retval < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_readdir(pdu->tag, pdu->id, fid, initial_offset, max_count);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        retval = -EINVAL;
+        goto out_nofid;
+    }
+    if (!fidp->fs.dir) {
+        retval = -EINVAL;
+        goto out;
+    }
+    if (initial_offset == 0) {
+        v9fs_co_rewinddir(pdu, fidp);
+    } else {
+        v9fs_co_seekdir(pdu, fidp, initial_offset);
+    }
+    count = v9fs_do_readdir(pdu, fidp, max_count);
+    if (count < 0) {
+        retval = count;
+        goto out;
+    }
+    retval = pdu_marshal(pdu, offset, "d", count);
+    if (retval < 0) {
+        goto out;
+    }
+    retval += count + offset;
+    trace_v9fs_readdir_return(pdu->tag, pdu->id, count, retval);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, retval);
+}
+
+static int v9fs_xattr_write(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
+                            uint64_t off, uint32_t count,
+                            struct iovec *sg, int cnt)
+{
+    int i, to_copy;
+    ssize_t err = 0;
+    int write_count;
+    int64_t xattr_len;
+    size_t offset = 7;
+
+
+    xattr_len = fidp->fs.xattr.len;
+    write_count = xattr_len - off;
+    if (write_count > count) {
+        write_count = count;
+    } else if (write_count < 0) {
+        /*
+         * write beyond XATTR value len specified in
+         * xattrcreate
+         */
+        err = -ENOSPC;
+        goto out;
+    }
+    err = pdu_marshal(pdu, offset, "d", write_count);
+    if (err < 0) {
+        return err;
+    }
+    err += offset;
+    fidp->fs.xattr.copied_len += write_count;
+    /*
+     * Now copy the content from sg list
+     */
+    for (i = 0; i < cnt; i++) {
+        if (write_count > sg[i].iov_len) {
+            to_copy = sg[i].iov_len;
+        } else {
+            to_copy = write_count;
+        }
+        memcpy((char *)fidp->fs.xattr.value + off, sg[i].iov_base, to_copy);
+        /* updating vs->off since we are not using below */
+        off += to_copy;
+        write_count -= to_copy;
+    }
+out:
+    return err;
+}
+
+static void v9fs_write(void *opaque)
+{
+    ssize_t err;
+    int32_t fid;
+    uint64_t off;
+    uint32_t count;
+    int32_t len = 0;
+    int32_t total = 0;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+    QEMUIOVector qiov_full;
+    QEMUIOVector qiov;
+
+    err = pdu_unmarshal(pdu, offset, "dqd", &fid, &off, &count);
+    if (err < 0) {
+        pdu_complete(pdu, err);
+        return;
+    }
+    offset += err;
+    v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset, count, true);
+    trace_v9fs_write(pdu->tag, pdu->id, fid, off, count, qiov_full.niov);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (fidp->fid_type == P9_FID_FILE) {
+        if (fidp->fs.fd == -1) {
+            err = -EINVAL;
+            goto out;
+        }
+    } else if (fidp->fid_type == P9_FID_XATTR) {
+        /*
+         * setxattr operation
+         */
+        err = v9fs_xattr_write(s, pdu, fidp, off, count,
+                               qiov_full.iov, qiov_full.niov);
+        goto out;
+    } else {
+        err = -EINVAL;
+        goto out;
+    }
+    qemu_iovec_init(&qiov, qiov_full.niov);
+    do {
+        qemu_iovec_reset(&qiov);
+        qemu_iovec_concat(&qiov, &qiov_full, total, qiov_full.size - total);
+        if (0) {
+            print_sg(qiov.iov, qiov.niov);
+        }
+        /* Loop in case of EINTR */
+        do {
+            len = v9fs_co_pwritev(pdu, fidp, qiov.iov, qiov.niov, off);
+            if (len >= 0) {
+                off   += len;
+                total += len;
+            }
+        } while (len == -EINTR && !pdu->cancelled);
+        if (len < 0) {
+            /* IO error return the error */
+            err = len;
+            goto out_qiov;
+        }
+    } while (total < count && len > 0);
+
+    offset = 7;
+    err = pdu_marshal(pdu, offset, "d", total);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_write_return(pdu->tag, pdu->id, total, err);
+out_qiov:
+    qemu_iovec_destroy(&qiov);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    qemu_iovec_destroy(&qiov_full);
+    pdu_complete(pdu, err);
+}
+
+static void v9fs_create(void *opaque)
+{
+    int32_t fid;
+    int err = 0;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    V9fsQID qid;
+    int32_t perm;
+    int8_t mode;
+    V9fsPath path;
+    struct stat stbuf;
+    V9fsString name;
+    V9fsString extension;
+    int iounit;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_path_init(&path);
+    v9fs_string_init(&name);
+    v9fs_string_init(&extension);
+    err = pdu_unmarshal(pdu, offset, "dsdbs", &fid, &name,
+                        &perm, &mode, &extension);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_create(pdu->tag, pdu->id, fid, name.data, perm, mode);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (perm & P9_STAT_MODE_DIR) {
+        err = v9fs_co_mkdir(pdu, fidp, &name, perm & 0777,
+                            fidp->uid, -1, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+        err = v9fs_co_opendir(pdu, fidp);
+        if (err < 0) {
+            goto out;
+        }
+        fidp->fid_type = P9_FID_DIR;
+    } else if (perm & P9_STAT_MODE_SYMLINK) {
+        err = v9fs_co_symlink(pdu, fidp, &name,
+                              extension.data, -1 , &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+    } else if (perm & P9_STAT_MODE_LINK) {
+        int32_t ofid = atoi(extension.data);
+        V9fsFidState *ofidp = get_fid(pdu, ofid);
+        if (ofidp == NULL) {
+            err = -EINVAL;
+            goto out;
+        }
+        err = v9fs_co_link(pdu, ofidp, fidp, &name);
+        put_fid(pdu, ofidp);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            fidp->fid_type = P9_FID_NONE;
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+        err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+        if (err < 0) {
+            fidp->fid_type = P9_FID_NONE;
+            goto out;
+        }
+    } else if (perm & P9_STAT_MODE_DEVICE) {
+        char ctype;
+        uint32_t major, minor;
+        mode_t nmode = 0;
+
+        if (sscanf(extension.data, "%c %u %u", &ctype, &major, &minor) != 3) {
+            err = -errno;
+            goto out;
+        }
+
+        switch (ctype) {
+        case 'c':
+            nmode = S_IFCHR;
+            break;
+        case 'b':
+            nmode = S_IFBLK;
+            break;
+        default:
+            err = -EIO;
+            goto out;
+        }
+
+        nmode |= perm & 0777;
+        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
+                            makedev(major, minor), nmode, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+    } else if (perm & P9_STAT_MODE_NAMED_PIPE) {
+        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
+                            0, S_IFIFO | (perm & 0777), &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+    } else if (perm & P9_STAT_MODE_SOCKET) {
+        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
+                            0, S_IFSOCK | (perm & 0777), &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
+        if (err < 0) {
+            goto out;
+        }
+        v9fs_path_copy(&fidp->path, &path);
+    } else {
+        err = v9fs_co_open2(pdu, fidp, &name, -1,
+                            omode_to_uflags(mode)|O_CREAT, perm, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        fidp->fid_type = P9_FID_FILE;
+        fidp->open_flags = omode_to_uflags(mode);
+        if (fidp->open_flags & O_EXCL) {
+            /*
+             * We let the host file system do O_EXCL check
+             * We should not reclaim such fd
+             */
+            fidp->flags |= FID_NON_RECLAIMABLE;
+        }
+    }
+    iounit = get_iounit(pdu, &fidp->path);
+    stat_to_qid(&stbuf, &qid);
+    err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_create_return(pdu->tag, pdu->id,
+                             qid.type, qid.version, qid.path, iounit);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+   pdu_complete(pdu, err);
+   v9fs_string_free(&name);
+   v9fs_string_free(&extension);
+   v9fs_path_free(&path);
+}
+
+static void v9fs_symlink(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    V9fsString name;
+    V9fsString symname;
+    V9fsFidState *dfidp;
+    V9fsQID qid;
+    struct stat stbuf;
+    int32_t dfid;
+    int err = 0;
+    gid_t gid;
+    size_t offset = 7;
+
+    v9fs_string_init(&name);
+    v9fs_string_init(&symname);
+    err = pdu_unmarshal(pdu, offset, "dssd", &dfid, &name, &symname, &gid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_symlink(pdu->tag, pdu->id, dfid, name.data, symname.data, gid);
+
+    dfidp = get_fid(pdu, dfid);
+    if (dfidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    err = v9fs_co_symlink(pdu, dfidp, &name, symname.data, gid, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    stat_to_qid(&stbuf, &qid);
+    err =  pdu_marshal(pdu, offset, "Q", &qid);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_symlink_return(pdu->tag, pdu->id,
+                              qid.type, qid.version, qid.path);
+out:
+    put_fid(pdu, dfidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+    v9fs_string_free(&symname);
+}
+
+static void v9fs_flush(void *opaque)
+{
+    ssize_t err;
+    int16_t tag;
+    size_t offset = 7;
+    V9fsPDU *cancel_pdu;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    err = pdu_unmarshal(pdu, offset, "w", &tag);
+    if (err < 0) {
+        pdu_complete(pdu, err);
+        return;
+    }
+    trace_v9fs_flush(pdu->tag, pdu->id, tag);
+
+    QLIST_FOREACH(cancel_pdu, &s->active_list, next) {
+        if (cancel_pdu->tag == tag) {
+            break;
+        }
+    }
+    if (cancel_pdu) {
+        cancel_pdu->cancelled = 1;
+        /*
+         * Wait for pdu to complete.
+         */
+        qemu_co_queue_wait(&cancel_pdu->complete);
+        cancel_pdu->cancelled = 0;
+        pdu_free(cancel_pdu);
+    }
+    pdu_complete(pdu, 7);
+}
+
+static void v9fs_link(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    int32_t dfid, oldfid;
+    V9fsFidState *dfidp, *oldfidp;
+    V9fsString name;
+    size_t offset = 7;
+    int err = 0;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dds", &dfid, &oldfid, &name);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_link(pdu->tag, pdu->id, dfid, oldfid, name.data);
+
+    dfidp = get_fid(pdu, dfid);
+    if (dfidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    oldfidp = get_fid(pdu, oldfid);
+    if (oldfidp == NULL) {
+        err = -ENOENT;
+        goto out;
+    }
+    err = v9fs_co_link(pdu, oldfidp, dfidp, &name);
+    if (!err) {
+        err = offset;
+    }
+out:
+    put_fid(pdu, dfidp);
+out_nofid:
+    v9fs_string_free(&name);
+    pdu_complete(pdu, err);
+}
+
+/* Only works with path name based fid */
+static void v9fs_remove(void *opaque)
+{
+    int32_t fid;
+    int err = 0;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+
+    err = pdu_unmarshal(pdu, offset, "d", &fid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_remove(pdu->tag, pdu->id, fid);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    /* if fs driver is not path based, return EOPNOTSUPP */
+    if (!(pdu->s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT)) {
+        err = -EOPNOTSUPP;
+        goto out_err;
+    }
+    /*
+     * IF the file is unlinked, we cannot reopen
+     * the file later. So don't reclaim fd
+     */
+    err = v9fs_mark_fids_unreclaim(pdu, &fidp->path);
+    if (err < 0) {
+        goto out_err;
+    }
+    err = v9fs_co_remove(pdu, &fidp->path);
+    if (!err) {
+        err = offset;
+    }
+out_err:
+    /* For TREMOVE we need to clunk the fid even on failed remove */
+    clunk_fid(pdu->s, fidp->fid);
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static void v9fs_unlinkat(void *opaque)
+{
+    int err = 0;
+    V9fsString name;
+    int32_t dfid, flags;
+    size_t offset = 7;
+    V9fsPath path;
+    V9fsFidState *dfidp;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dsd", &dfid, &name, &flags);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    dfidp = get_fid(pdu, dfid);
+    if (dfidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    /*
+     * IF the file is unlinked, we cannot reopen
+     * the file later. So don't reclaim fd
+     */
+    v9fs_path_init(&path);
+    err = v9fs_co_name_to_path(pdu, &dfidp->path, name.data, &path);
+    if (err < 0) {
+        goto out_err;
+    }
+    err = v9fs_mark_fids_unreclaim(pdu, &path);
+    if (err < 0) {
+        goto out_err;
+    }
+    err = v9fs_co_unlinkat(pdu, &dfidp->path, &name, flags);
+    if (!err) {
+        err = offset;
+    }
+out_err:
+    put_fid(pdu, dfidp);
+    v9fs_path_free(&path);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+
+/* Only works with path name based fid */
+static int v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
+                                int32_t newdirfid, V9fsString *name)
+{
+    char *end;
+    int err = 0;
+    V9fsPath new_path;
+    V9fsFidState *tfidp;
+    V9fsState *s = pdu->s;
+    V9fsFidState *dirfidp = NULL;
+    char *old_name, *new_name;
+
+    v9fs_path_init(&new_path);
+    if (newdirfid != -1) {
+        dirfidp = get_fid(pdu, newdirfid);
+        if (dirfidp == NULL) {
+            err = -ENOENT;
+            goto out_nofid;
+        }
+        BUG_ON(dirfidp->fid_type != P9_FID_NONE);
+        v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path);
+    } else {
+        old_name = fidp->path.data;
+        end = strrchr(old_name, '/');
+        if (end) {
+            end++;
+        } else {
+            end = old_name;
+        }
+        new_name = g_malloc0(end - old_name + name->size + 1);
+        strncat(new_name, old_name, end - old_name);
+        strncat(new_name + (end - old_name), name->data, name->size);
+        v9fs_co_name_to_path(pdu, NULL, new_name, &new_path);
+        g_free(new_name);
+    }
+    err = v9fs_co_rename(pdu, &fidp->path, &new_path);
+    if (err < 0) {
+        goto out;
+    }
+    /*
+     * Fixup fid's pointing to the old name to
+     * start pointing to the new name
+     */
+    for (tfidp = s->fid_list; tfidp; tfidp = tfidp->next) {
+        if (v9fs_path_is_ancestor(&fidp->path, &tfidp->path)) {
+            /* replace the name */
+            v9fs_fix_path(&tfidp->path, &new_path, strlen(fidp->path.data));
+        }
+    }
+out:
+    if (dirfidp) {
+        put_fid(pdu, dirfidp);
+    }
+    v9fs_path_free(&new_path);
+out_nofid:
+    return err;
+}
+
+/* Only works with path name based fid */
+static void v9fs_rename(void *opaque)
+{
+    int32_t fid;
+    ssize_t err = 0;
+    size_t offset = 7;
+    V9fsString name;
+    int32_t newdirfid;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dds", &fid, &newdirfid, &name);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    BUG_ON(fidp->fid_type != P9_FID_NONE);
+    /* if fs driver is not path based, return EOPNOTSUPP */
+    if (!(pdu->s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT)) {
+        err = -EOPNOTSUPP;
+        goto out;
+    }
+    v9fs_path_write_lock(s);
+    err = v9fs_complete_rename(pdu, fidp, newdirfid, &name);
+    v9fs_path_unlock(s);
+    if (!err) {
+        err = offset;
+    }
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
+                               V9fsString *old_name, V9fsPath *newdir,
+                               V9fsString *new_name)
+{
+    V9fsFidState *tfidp;
+    V9fsPath oldpath, newpath;
+    V9fsState *s = pdu->s;
+
+
+    v9fs_path_init(&oldpath);
+    v9fs_path_init(&newpath);
+    v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath);
+    v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath);
+
+    /*
+     * Fixup fid's pointing to the old name to
+     * start pointing to the new name
+     */
+    for (tfidp = s->fid_list; tfidp; tfidp = tfidp->next) {
+        if (v9fs_path_is_ancestor(&oldpath, &tfidp->path)) {
+            /* replace the name */
+            v9fs_fix_path(&tfidp->path, &newpath, strlen(oldpath.data));
+        }
+    }
+    v9fs_path_free(&oldpath);
+    v9fs_path_free(&newpath);
+}
+
+static int v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
+                                  V9fsString *old_name, int32_t newdirfid,
+                                  V9fsString *new_name)
+{
+    int err = 0;
+    V9fsState *s = pdu->s;
+    V9fsFidState *newdirfidp = NULL, *olddirfidp = NULL;
+
+    olddirfidp = get_fid(pdu, olddirfid);
+    if (olddirfidp == NULL) {
+        err = -ENOENT;
+        goto out;
+    }
+    if (newdirfid != -1) {
+        newdirfidp = get_fid(pdu, newdirfid);
+        if (newdirfidp == NULL) {
+            err = -ENOENT;
+            goto out;
+        }
+    } else {
+        newdirfidp = get_fid(pdu, olddirfid);
+    }
+
+    err = v9fs_co_renameat(pdu, &olddirfidp->path, old_name,
+                           &newdirfidp->path, new_name);
+    if (err < 0) {
+        goto out;
+    }
+    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
+        /* Only for path based fid  we need to do the below fixup */
+        v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name,
+                           &newdirfidp->path, new_name);
+    }
+out:
+    if (olddirfidp) {
+        put_fid(pdu, olddirfidp);
+    }
+    if (newdirfidp) {
+        put_fid(pdu, newdirfidp);
+    }
+    return err;
+}
+
+static void v9fs_renameat(void *opaque)
+{
+    ssize_t err = 0;
+    size_t offset = 7;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+    int32_t olddirfid, newdirfid;
+    V9fsString old_name, new_name;
+
+    v9fs_string_init(&old_name);
+    v9fs_string_init(&new_name);
+    err = pdu_unmarshal(pdu, offset, "dsds", &olddirfid,
+                        &old_name, &newdirfid, &new_name);
+    if (err < 0) {
+        goto out_err;
+    }
+
+    v9fs_path_write_lock(s);
+    err = v9fs_complete_renameat(pdu, olddirfid,
+                                 &old_name, newdirfid, &new_name);
+    v9fs_path_unlock(s);
+    if (!err) {
+        err = offset;
+    }
+
+out_err:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&old_name);
+    v9fs_string_free(&new_name);
+}
+
+static void v9fs_wstat(void *opaque)
+{
+    int32_t fid;
+    int err = 0;
+    int16_t unused;
+    V9fsStat v9stat;
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_stat_init(&v9stat);
+    err = pdu_unmarshal(pdu, offset, "dwS", &fid, &unused, &v9stat);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_wstat(pdu->tag, pdu->id, fid,
+                     v9stat.mode, v9stat.atime, v9stat.mtime);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    /* do we need to sync the file? */
+    if (donttouch_stat(&v9stat)) {
+        err = v9fs_co_fsync(pdu, fidp, 0);
+        goto out;
+    }
+    if (v9stat.mode != -1) {
+        uint32_t v9_mode;
+        err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+        if (err < 0) {
+            goto out;
+        }
+        v9_mode = stat_to_v9mode(&stbuf);
+        if ((v9stat.mode & P9_STAT_MODE_TYPE_BITS) !=
+            (v9_mode & P9_STAT_MODE_TYPE_BITS)) {
+            /* Attempting to change the type */
+            err = -EIO;
+            goto out;
+        }
+        err = v9fs_co_chmod(pdu, &fidp->path,
+                            v9mode_to_mode(v9stat.mode,
+                                           &v9stat.extension));
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9stat.mtime != -1 || v9stat.atime != -1) {
+        struct timespec times[2];
+        if (v9stat.atime != -1) {
+            times[0].tv_sec = v9stat.atime;
+            times[0].tv_nsec = 0;
+        } else {
+            times[0].tv_nsec = UTIME_OMIT;
+        }
+        if (v9stat.mtime != -1) {
+            times[1].tv_sec = v9stat.mtime;
+            times[1].tv_nsec = 0;
+        } else {
+            times[1].tv_nsec = UTIME_OMIT;
+        }
+        err = v9fs_co_utimensat(pdu, &fidp->path, times);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9stat.n_gid != -1 || v9stat.n_uid != -1) {
+        err = v9fs_co_chown(pdu, &fidp->path, v9stat.n_uid, v9stat.n_gid);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9stat.name.size != 0) {
+        err = v9fs_complete_rename(pdu, fidp, -1, &v9stat.name);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    if (v9stat.length != -1) {
+        err = v9fs_co_truncate(pdu, &fidp->path, v9stat.length);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    err = offset;
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    v9fs_stat_free(&v9stat);
+    pdu_complete(pdu, err);
+}
+
+static int v9fs_fill_statfs(V9fsState *s, V9fsPDU *pdu, struct statfs *stbuf)
+{
+    uint32_t f_type;
+    uint32_t f_bsize;
+    uint64_t f_blocks;
+    uint64_t f_bfree;
+    uint64_t f_bavail;
+    uint64_t f_files;
+    uint64_t f_ffree;
+    uint64_t fsid_val;
+    uint32_t f_namelen;
+    size_t offset = 7;
+    int32_t bsize_factor;
+
+    /*
+     * compute bsize factor based on host file system block size
+     * and client msize
+     */
+    bsize_factor = (s->msize - P9_IOHDRSZ)/stbuf->f_bsize;
+    if (!bsize_factor) {
+        bsize_factor = 1;
+    }
+    f_type  = stbuf->f_type;
+    f_bsize = stbuf->f_bsize;
+    f_bsize *= bsize_factor;
+    /*
+     * f_bsize is adjusted(multiplied) by bsize factor, so we need to
+     * adjust(divide) the number of blocks, free blocks and available
+     * blocks by bsize factor
+     */
+    f_blocks = stbuf->f_blocks/bsize_factor;
+    f_bfree  = stbuf->f_bfree/bsize_factor;
+    f_bavail = stbuf->f_bavail/bsize_factor;
+    f_files  = stbuf->f_files;
+    f_ffree  = stbuf->f_ffree;
+    fsid_val = (unsigned int) stbuf->f_fsid.__val[0] |
+               (unsigned long long)stbuf->f_fsid.__val[1] << 32;
+    f_namelen = stbuf->f_namelen;
+
+    return pdu_marshal(pdu, offset, "ddqqqqqqd",
+                       f_type, f_bsize, f_blocks, f_bfree,
+                       f_bavail, f_files, f_ffree,
+                       fsid_val, f_namelen);
+}
+
+static void v9fs_statfs(void *opaque)
+{
+    int32_t fid;
+    ssize_t retval = 0;
+    size_t offset = 7;
+    V9fsFidState *fidp;
+    struct statfs stbuf;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    retval = pdu_unmarshal(pdu, offset, "d", &fid);
+    if (retval < 0) {
+        goto out_nofid;
+    }
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        retval = -ENOENT;
+        goto out_nofid;
+    }
+    retval = v9fs_co_statfs(pdu, &fidp->path, &stbuf);
+    if (retval < 0) {
+        goto out;
+    }
+    retval = v9fs_fill_statfs(s, pdu, &stbuf);
+    if (retval < 0) {
+        goto out;
+    }
+    retval += offset;
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, retval);
+}
+
+static void v9fs_mknod(void *opaque)
+{
+
+    int mode;
+    gid_t gid;
+    int32_t fid;
+    V9fsQID qid;
+    int err = 0;
+    int major, minor;
+    size_t offset = 7;
+    V9fsString name;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dsdddd", &fid, &name, &mode,
+                        &major, &minor, &gid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_mknod(pdu->tag, pdu->id, fid, mode, major, minor);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, gid,
+                        makedev(major, minor), mode, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    stat_to_qid(&stbuf, &qid);
+    err = pdu_marshal(pdu, offset, "Q", &qid);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_mknod_return(pdu->tag, pdu->id,
+                            qid.type, qid.version, qid.path);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+/*
+ * Implement posix byte range locking code
+ * Server side handling of locking code is very simple, because 9p server in
+ * QEMU can handle only one client. And most of the lock handling
+ * (like conflict, merging) etc is done by the VFS layer itself, so no need to
+ * do any thing in * qemu 9p server side lock code path.
+ * So when a TLOCK request comes, always return success
+ */
+static void v9fs_lock(void *opaque)
+{
+    int8_t status;
+    V9fsFlock flock;
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    int32_t fid, err = 0;
+    V9fsPDU *pdu = opaque;
+
+    status = P9_LOCK_ERROR;
+    v9fs_string_init(&flock.client_id);
+    err = pdu_unmarshal(pdu, offset, "dbdqqds", &fid, &flock.type,
+                        &flock.flags, &flock.start, &flock.length,
+                        &flock.proc_id, &flock.client_id);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_lock(pdu->tag, pdu->id, fid,
+                    flock.type, flock.start, flock.length);
+
+
+    /* We support only block flag now (that too ignored currently) */
+    if (flock.flags & ~P9_LOCK_FLAGS_BLOCK) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_fstat(pdu, fidp, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    status = P9_LOCK_SUCCESS;
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    err = pdu_marshal(pdu, offset, "b", status);
+    if (err > 0) {
+        err += offset;
+    }
+    trace_v9fs_lock_return(pdu->tag, pdu->id, status);
+    pdu_complete(pdu, err);
+    v9fs_string_free(&flock.client_id);
+}
+
+/*
+ * When a TGETLOCK request comes, always return success because all lock
+ * handling is done by client's VFS layer.
+ */
+static void v9fs_getlock(void *opaque)
+{
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    V9fsGetlock glock;
+    int32_t fid, err = 0;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_string_init(&glock.client_id);
+    err = pdu_unmarshal(pdu, offset, "dbqqds", &fid, &glock.type,
+                        &glock.start, &glock.length, &glock.proc_id,
+                        &glock.client_id);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_getlock(pdu->tag, pdu->id, fid,
+                       glock.type, glock.start, glock.length);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_fstat(pdu, fidp, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    glock.type = P9_LOCK_TYPE_UNLCK;
+    err = pdu_marshal(pdu, offset, "bqqds", glock.type,
+                          glock.start, glock.length, glock.proc_id,
+                          &glock.client_id);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_getlock_return(pdu->tag, pdu->id, glock.type, glock.start,
+                              glock.length, glock.proc_id);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&glock.client_id);
+}
+
+static void v9fs_mkdir(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    size_t offset = 7;
+    int32_t fid;
+    struct stat stbuf;
+    V9fsQID qid;
+    V9fsString name;
+    V9fsFidState *fidp;
+    gid_t gid;
+    int mode;
+    int err = 0;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dsdd", &fid, &name, &mode, &gid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_mkdir(pdu->tag, pdu->id, fid, name.data, mode, gid);
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    err = v9fs_co_mkdir(pdu, fidp, &name, mode, fidp->uid, gid, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    stat_to_qid(&stbuf, &qid);
+    err = pdu_marshal(pdu, offset, "Q", &qid);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_mkdir_return(pdu->tag, pdu->id,
+                            qid.type, qid.version, qid.path, err);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void v9fs_xattrwalk(void *opaque)
+{
+    int64_t size;
+    V9fsString name;
+    ssize_t err = 0;
+    size_t offset = 7;
+    int32_t fid, newfid;
+    V9fsFidState *file_fidp;
+    V9fsFidState *xattr_fidp = NULL;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dds", &fid, &newfid, &name);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_xattrwalk(pdu->tag, pdu->id, fid, newfid, name.data);
+
+    file_fidp = get_fid(pdu, fid);
+    if (file_fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    xattr_fidp = alloc_fid(s, newfid);
+    if (xattr_fidp == NULL) {
+        err = -EINVAL;
+        goto out;
+    }
+    v9fs_path_copy(&xattr_fidp->path, &file_fidp->path);
+    if (name.data == NULL) {
+        /*
+         * listxattr request. Get the size first
+         */
+        size = v9fs_co_llistxattr(pdu, &xattr_fidp->path, NULL, 0);
+        if (size < 0) {
+            err = size;
+            clunk_fid(s, xattr_fidp->fid);
+            goto out;
+        }
+        /*
+         * Read the xattr value
+         */
+        xattr_fidp->fs.xattr.len = size;
+        xattr_fidp->fid_type = P9_FID_XATTR;
+        xattr_fidp->fs.xattr.copied_len = -1;
+        if (size) {
+            xattr_fidp->fs.xattr.value = g_malloc(size);
+            err = v9fs_co_llistxattr(pdu, &xattr_fidp->path,
+                                     xattr_fidp->fs.xattr.value,
+                                     xattr_fidp->fs.xattr.len);
+            if (err < 0) {
+                clunk_fid(s, xattr_fidp->fid);
+                goto out;
+            }
+        }
+        err = pdu_marshal(pdu, offset, "q", size);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset;
+    } else {
+        /*
+         * specific xattr fid. We check for xattr
+         * presence also collect the xattr size
+         */
+        size = v9fs_co_lgetxattr(pdu, &xattr_fidp->path,
+                                 &name, NULL, 0);
+        if (size < 0) {
+            err = size;
+            clunk_fid(s, xattr_fidp->fid);
+            goto out;
+        }
+        /*
+         * Read the xattr value
+         */
+        xattr_fidp->fs.xattr.len = size;
+        xattr_fidp->fid_type = P9_FID_XATTR;
+        xattr_fidp->fs.xattr.copied_len = -1;
+        if (size) {
+            xattr_fidp->fs.xattr.value = g_malloc(size);
+            err = v9fs_co_lgetxattr(pdu, &xattr_fidp->path,
+                                    &name, xattr_fidp->fs.xattr.value,
+                                    xattr_fidp->fs.xattr.len);
+            if (err < 0) {
+                clunk_fid(s, xattr_fidp->fid);
+                goto out;
+            }
+        }
+        err = pdu_marshal(pdu, offset, "q", size);
+        if (err < 0) {
+            goto out;
+        }
+        err += offset;
+    }
+    trace_v9fs_xattrwalk_return(pdu->tag, pdu->id, size);
+out:
+    put_fid(pdu, file_fidp);
+    if (xattr_fidp) {
+        put_fid(pdu, xattr_fidp);
+    }
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void v9fs_xattrcreate(void *opaque)
+{
+    int flags;
+    int32_t fid;
+    int64_t size;
+    ssize_t err = 0;
+    V9fsString name;
+    size_t offset = 7;
+    V9fsFidState *file_fidp;
+    V9fsFidState *xattr_fidp;
+    V9fsPDU *pdu = opaque;
+
+    v9fs_string_init(&name);
+    err = pdu_unmarshal(pdu, offset, "dsqd", &fid, &name, &size, &flags);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_xattrcreate(pdu->tag, pdu->id, fid, name.data, size, flags);
+
+    file_fidp = get_fid(pdu, fid);
+    if (file_fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    /* Make the file fid point to xattr */
+    xattr_fidp = file_fidp;
+    xattr_fidp->fid_type = P9_FID_XATTR;
+    xattr_fidp->fs.xattr.copied_len = 0;
+    xattr_fidp->fs.xattr.len = size;
+    xattr_fidp->fs.xattr.flags = flags;
+    v9fs_string_init(&xattr_fidp->fs.xattr.name);
+    v9fs_string_copy(&xattr_fidp->fs.xattr.name, &name);
+    xattr_fidp->fs.xattr.value = g_malloc(size);
+    err = offset;
+    put_fid(pdu, file_fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void v9fs_readlink(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    size_t offset = 7;
+    V9fsString target;
+    int32_t fid;
+    int err = 0;
+    V9fsFidState *fidp;
+
+    err = pdu_unmarshal(pdu, offset, "d", &fid);
+    if (err < 0) {
+        goto out_nofid;
+    }
+    trace_v9fs_readlink(pdu->tag, pdu->id, fid);
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    v9fs_string_init(&target);
+    err = v9fs_co_readlink(pdu, &fidp->path, &target);
+    if (err < 0) {
+        goto out;
+    }
+    err = pdu_marshal(pdu, offset, "s", &target);
+    if (err < 0) {
+        v9fs_string_free(&target);
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_readlink_return(pdu->tag, pdu->id, target.data);
+    v9fs_string_free(&target);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+}
+
+static CoroutineEntry *pdu_co_handlers[] = {
+    [P9_TREADDIR] = v9fs_readdir,
+    [P9_TSTATFS] = v9fs_statfs,
+    [P9_TGETATTR] = v9fs_getattr,
+    [P9_TSETATTR] = v9fs_setattr,
+    [P9_TXATTRWALK] = v9fs_xattrwalk,
+    [P9_TXATTRCREATE] = v9fs_xattrcreate,
+    [P9_TMKNOD] = v9fs_mknod,
+    [P9_TRENAME] = v9fs_rename,
+    [P9_TLOCK] = v9fs_lock,
+    [P9_TGETLOCK] = v9fs_getlock,
+    [P9_TRENAMEAT] = v9fs_renameat,
+    [P9_TREADLINK] = v9fs_readlink,
+    [P9_TUNLINKAT] = v9fs_unlinkat,
+    [P9_TMKDIR] = v9fs_mkdir,
+    [P9_TVERSION] = v9fs_version,
+    [P9_TLOPEN] = v9fs_open,
+    [P9_TATTACH] = v9fs_attach,
+    [P9_TSTAT] = v9fs_stat,
+    [P9_TWALK] = v9fs_walk,
+    [P9_TCLUNK] = v9fs_clunk,
+    [P9_TFSYNC] = v9fs_fsync,
+    [P9_TOPEN] = v9fs_open,
+    [P9_TREAD] = v9fs_read,
+#if 0
+    [P9_TAUTH] = v9fs_auth,
+#endif
+    [P9_TFLUSH] = v9fs_flush,
+    [P9_TLINK] = v9fs_link,
+    [P9_TSYMLINK] = v9fs_symlink,
+    [P9_TCREATE] = v9fs_create,
+    [P9_TLCREATE] = v9fs_lcreate,
+    [P9_TWRITE] = v9fs_write,
+    [P9_TWSTAT] = v9fs_wstat,
+    [P9_TREMOVE] = v9fs_remove,
+};
+
+static void v9fs_op_not_supp(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    pdu_complete(pdu, -EOPNOTSUPP);
+}
+
+static void v9fs_fs_ro(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    pdu_complete(pdu, -EROFS);
+}
+
+static inline bool is_read_only_op(V9fsPDU *pdu)
+{
+    switch (pdu->id) {
+    case P9_TREADDIR:
+    case P9_TSTATFS:
+    case P9_TGETATTR:
+    case P9_TXATTRWALK:
+    case P9_TLOCK:
+    case P9_TGETLOCK:
+    case P9_TREADLINK:
+    case P9_TVERSION:
+    case P9_TLOPEN:
+    case P9_TATTACH:
+    case P9_TSTAT:
+    case P9_TWALK:
+    case P9_TCLUNK:
+    case P9_TFSYNC:
+    case P9_TOPEN:
+    case P9_TREAD:
+    case P9_TAUTH:
+    case P9_TFLUSH:
+        return 1;
+    default:
+        return 0;
+    }
+}
+
+void pdu_submit(V9fsPDU *pdu)
+{
+    Coroutine *co;
+    CoroutineEntry *handler;
+    V9fsState *s = pdu->s;
+
+    if (pdu->id >= ARRAY_SIZE(pdu_co_handlers) ||
+        (pdu_co_handlers[pdu->id] == NULL)) {
+        handler = v9fs_op_not_supp;
+    } else {
+        handler = pdu_co_handlers[pdu->id];
+    }
+
+    if (is_ro_export(&s->ctx) && !is_read_only_op(pdu)) {
+        handler = v9fs_fs_ro;
+    }
+    co = qemu_coroutine_create(handler);
+    qemu_coroutine_enter(co, pdu);
+}
+
+static void __attribute__((__constructor__)) v9fs_set_fd_limit(void)
+{
+    struct rlimit rlim;
+    if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
+        fprintf(stderr, "Failed to get the resource limit\n");
+        exit(1);
+    }
+    open_fd_hw = rlim.rlim_cur - MIN(400, rlim.rlim_cur/3);
+    open_fd_rc = rlim.rlim_cur/2;
+}
diff --git a/hw/9pfs/Makefile.objs b/hw/9pfs/Makefile.objs
index d5778728d5..fcffefe373 100644
--- a/hw/9pfs/Makefile.objs
+++ b/hw/9pfs/Makefile.objs
@@ -1,4 +1,4 @@
-common-obj-y  = virtio-9p.o
+common-obj-y  = 9p.o
 common-obj-y += 9p-local.o 9p-xattr.o
 common-obj-y += 9p-xattr-user.o 9p-posix-acl.o
 common-obj-y += virtio-9p-coth.o cofs.o codir.o cofile.o
diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c
deleted file mode 100644
index 800f01ead3..0000000000
--- a/hw/9pfs/virtio-9p.c
+++ /dev/null
@@ -1,3269 +0,0 @@
-/*
- * Virtio 9p backend
- *
- * Copyright IBM, Corp. 2010
- *
- * Authors:
- *  Anthony Liguori   <aliguori@us.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2.  See
- * the COPYING file in the top-level directory.
- *
- */
-
-#include "hw/virtio.h"
-#include "hw/pc.h"
-#include "qemu/sockets.h"
-#include "virtio-9p.h"
-#include "fsdev/qemu-fsdev.h"
-#include "9p-xattr.h"
-#include "virtio-9p-coth.h"
-#include "trace.h"
-#include "migration/migration.h"
-
-int open_fd_hw;
-int total_open_fd;
-static int open_fd_rc;
-
-enum {
-    Oread   = 0x00,
-    Owrite  = 0x01,
-    Ordwr   = 0x02,
-    Oexec   = 0x03,
-    Oexcl   = 0x04,
-    Otrunc  = 0x10,
-    Orexec  = 0x20,
-    Orclose = 0x40,
-    Oappend = 0x80,
-};
-
-ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
-{
-    ssize_t ret;
-    va_list ap;
-
-    va_start(ap, fmt);
-    ret = virtio_pdu_vmarshal(pdu, offset, fmt, ap);
-    va_end(ap);
-
-    return ret;
-}
-
-ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
-{
-    ssize_t ret;
-    va_list ap;
-
-    va_start(ap, fmt);
-    ret = virtio_pdu_vunmarshal(pdu, offset, fmt, ap);
-    va_end(ap);
-
-    return ret;
-}
-
-static void pdu_push_and_notify(V9fsPDU *pdu)
-{
-    virtio_9p_push_and_notify(pdu);
-}
-
-static int omode_to_uflags(int8_t mode)
-{
-    int ret = 0;
-
-    switch (mode & 3) {
-    case Oread:
-        ret = O_RDONLY;
-        break;
-    case Ordwr:
-        ret = O_RDWR;
-        break;
-    case Owrite:
-        ret = O_WRONLY;
-        break;
-    case Oexec:
-        ret = O_RDONLY;
-        break;
-    }
-
-    if (mode & Otrunc) {
-        ret |= O_TRUNC;
-    }
-
-    if (mode & Oappend) {
-        ret |= O_APPEND;
-    }
-
-    if (mode & Oexcl) {
-        ret |= O_EXCL;
-    }
-
-    return ret;
-}
-
-struct dotl_openflag_map {
-    int dotl_flag;
-    int open_flag;
-};
-
-static int dotl_to_open_flags(int flags)
-{
-    int i;
-    /*
-     * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
-     * and P9_DOTL_NOACCESS
-     */
-    int oflags = flags & O_ACCMODE;
-
-    struct dotl_openflag_map dotl_oflag_map[] = {
-        { P9_DOTL_CREATE, O_CREAT },
-        { P9_DOTL_EXCL, O_EXCL },
-        { P9_DOTL_NOCTTY , O_NOCTTY },
-        { P9_DOTL_TRUNC, O_TRUNC },
-        { P9_DOTL_APPEND, O_APPEND },
-        { P9_DOTL_NONBLOCK, O_NONBLOCK } ,
-        { P9_DOTL_DSYNC, O_DSYNC },
-        { P9_DOTL_FASYNC, FASYNC },
-        { P9_DOTL_DIRECT, O_DIRECT },
-        { P9_DOTL_LARGEFILE, O_LARGEFILE },
-        { P9_DOTL_DIRECTORY, O_DIRECTORY },
-        { P9_DOTL_NOFOLLOW, O_NOFOLLOW },
-        { P9_DOTL_NOATIME, O_NOATIME },
-        { P9_DOTL_SYNC, O_SYNC },
-    };
-
-    for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
-        if (flags & dotl_oflag_map[i].dotl_flag) {
-            oflags |= dotl_oflag_map[i].open_flag;
-        }
-    }
-
-    return oflags;
-}
-
-void cred_init(FsCred *credp)
-{
-    credp->fc_uid = -1;
-    credp->fc_gid = -1;
-    credp->fc_mode = -1;
-    credp->fc_rdev = -1;
-}
-
-static int get_dotl_openflags(V9fsState *s, int oflags)
-{
-    int flags;
-    /*
-     * Filter the client open flags
-     */
-    flags = dotl_to_open_flags(oflags);
-    flags &= ~(O_NOCTTY | O_ASYNC | O_CREAT);
-    /*
-     * Ignore direct disk access hint until the server supports it.
-     */
-    flags &= ~O_DIRECT;
-    return flags;
-}
-
-void v9fs_path_init(V9fsPath *path)
-{
-    path->data = NULL;
-    path->size = 0;
-}
-
-void v9fs_path_free(V9fsPath *path)
-{
-    g_free(path->data);
-    path->data = NULL;
-    path->size = 0;
-}
-
-void v9fs_path_copy(V9fsPath *lhs, V9fsPath *rhs)
-{
-    v9fs_path_free(lhs);
-    lhs->data = g_malloc(rhs->size);
-    memcpy(lhs->data, rhs->data, rhs->size);
-    lhs->size = rhs->size;
-}
-
-int v9fs_name_to_path(V9fsState *s, V9fsPath *dirpath,
-                      const char *name, V9fsPath *path)
-{
-    int err;
-    err = s->ops->name_to_path(&s->ctx, dirpath, name, path);
-    if (err < 0) {
-        err = -errno;
-    }
-    return err;
-}
-
-/*
- * Return TRUE if s1 is an ancestor of s2.
- *
- * E.g. "a/b" is an ancestor of "a/b/c" but not of "a/bc/d".
- * As a special case, We treat s1 as ancestor of s2 if they are same!
- */
-static int v9fs_path_is_ancestor(V9fsPath *s1, V9fsPath *s2)
-{
-    if (!strncmp(s1->data, s2->data, s1->size - 1)) {
-        if (s2->data[s1->size - 1] == '\0' || s2->data[s1->size - 1] == '/') {
-            return 1;
-        }
-    }
-    return 0;
-}
-
-static size_t v9fs_string_size(V9fsString *str)
-{
-    return str->size;
-}
-
-/*
- * returns 0 if fid got re-opened, 1 if not, < 0 on error */
-static int v9fs_reopen_fid(V9fsPDU *pdu, V9fsFidState *f)
-{
-    int err = 1;
-    if (f->fid_type == P9_FID_FILE) {
-        if (f->fs.fd == -1) {
-            do {
-                err = v9fs_co_open(pdu, f, f->open_flags);
-            } while (err == -EINTR && !pdu->cancelled);
-        }
-    } else if (f->fid_type == P9_FID_DIR) {
-        if (f->fs.dir == NULL) {
-            do {
-                err = v9fs_co_opendir(pdu, f);
-            } while (err == -EINTR && !pdu->cancelled);
-        }
-    }
-    return err;
-}
-
-static V9fsFidState *get_fid(V9fsPDU *pdu, int32_t fid)
-{
-    int err;
-    V9fsFidState *f;
-    V9fsState *s = pdu->s;
-
-    for (f = s->fid_list; f; f = f->next) {
-        BUG_ON(f->clunked);
-        if (f->fid == fid) {
-            /*
-             * Update the fid ref upfront so that
-             * we don't get reclaimed when we yield
-             * in open later.
-             */
-            f->ref++;
-            /*
-             * check whether we need to reopen the
-             * file. We might have closed the fd
-             * while trying to free up some file
-             * descriptors.
-             */
-            err = v9fs_reopen_fid(pdu, f);
-            if (err < 0) {
-                f->ref--;
-                return NULL;
-            }
-            /*
-             * Mark the fid as referenced so that the LRU
-             * reclaim won't close the file descriptor
-             */
-            f->flags |= FID_REFERENCED;
-            return f;
-        }
-    }
-    return NULL;
-}
-
-static V9fsFidState *alloc_fid(V9fsState *s, int32_t fid)
-{
-    V9fsFidState *f;
-
-    for (f = s->fid_list; f; f = f->next) {
-        /* If fid is already there return NULL */
-        BUG_ON(f->clunked);
-        if (f->fid == fid) {
-            return NULL;
-        }
-    }
-    f = g_malloc0(sizeof(V9fsFidState));
-    f->fid = fid;
-    f->fid_type = P9_FID_NONE;
-    f->ref = 1;
-    /*
-     * Mark the fid as referenced so that the LRU
-     * reclaim won't close the file descriptor
-     */
-    f->flags |= FID_REFERENCED;
-    f->next = s->fid_list;
-    s->fid_list = f;
-
-    return f;
-}
-
-static int v9fs_xattr_fid_clunk(V9fsPDU *pdu, V9fsFidState *fidp)
-{
-    int retval = 0;
-
-    if (fidp->fs.xattr.copied_len == -1) {
-        /* getxattr/listxattr fid */
-        goto free_value;
-    }
-    /*
-     * if this is fid for setxattr. clunk should
-     * result in setxattr localcall
-     */
-    if (fidp->fs.xattr.len != fidp->fs.xattr.copied_len) {
-        /* clunk after partial write */
-        retval = -EINVAL;
-        goto free_out;
-    }
-    if (fidp->fs.xattr.len) {
-        retval = v9fs_co_lsetxattr(pdu, &fidp->path, &fidp->fs.xattr.name,
-                                   fidp->fs.xattr.value,
-                                   fidp->fs.xattr.len,
-                                   fidp->fs.xattr.flags);
-    } else {
-        retval = v9fs_co_lremovexattr(pdu, &fidp->path, &fidp->fs.xattr.name);
-    }
-free_out:
-    v9fs_string_free(&fidp->fs.xattr.name);
-free_value:
-    if (fidp->fs.xattr.value) {
-        g_free(fidp->fs.xattr.value);
-    }
-    return retval;
-}
-
-static int free_fid(V9fsPDU *pdu, V9fsFidState *fidp)
-{
-    int retval = 0;
-
-    if (fidp->fid_type == P9_FID_FILE) {
-        /* If we reclaimed the fd no need to close */
-        if (fidp->fs.fd != -1) {
-            retval = v9fs_co_close(pdu, &fidp->fs);
-        }
-    } else if (fidp->fid_type == P9_FID_DIR) {
-        if (fidp->fs.dir != NULL) {
-            retval = v9fs_co_closedir(pdu, &fidp->fs);
-        }
-    } else if (fidp->fid_type == P9_FID_XATTR) {
-        retval = v9fs_xattr_fid_clunk(pdu, fidp);
-    }
-    v9fs_path_free(&fidp->path);
-    g_free(fidp);
-    return retval;
-}
-
-static int put_fid(V9fsPDU *pdu, V9fsFidState *fidp)
-{
-    BUG_ON(!fidp->ref);
-    fidp->ref--;
-    /*
-     * Don't free the fid if it is in reclaim list
-     */
-    if (!fidp->ref && fidp->clunked) {
-        if (fidp->fid == pdu->s->root_fid) {
-            /*
-             * if the clunked fid is root fid then we
-             * have unmounted the fs on the client side.
-             * delete the migration blocker. Ideally, this
-             * should be hooked to transport close notification
-             */
-            if (pdu->s->migration_blocker) {
-                migrate_del_blocker(pdu->s->migration_blocker);
-                error_free(pdu->s->migration_blocker);
-                pdu->s->migration_blocker = NULL;
-            }
-        }
-        return free_fid(pdu, fidp);
-    }
-    return 0;
-}
-
-static V9fsFidState *clunk_fid(V9fsState *s, int32_t fid)
-{
-    V9fsFidState **fidpp, *fidp;
-
-    for (fidpp = &s->fid_list; *fidpp; fidpp = &(*fidpp)->next) {
-        if ((*fidpp)->fid == fid) {
-            break;
-        }
-    }
-    if (*fidpp == NULL) {
-        return NULL;
-    }
-    fidp = *fidpp;
-    *fidpp = fidp->next;
-    fidp->clunked = 1;
-    return fidp;
-}
-
-void v9fs_reclaim_fd(V9fsPDU *pdu)
-{
-    int reclaim_count = 0;
-    V9fsState *s = pdu->s;
-    V9fsFidState *f, *reclaim_list = NULL;
-
-    for (f = s->fid_list; f; f = f->next) {
-        /*
-         * Unlink fids cannot be reclaimed. Check
-         * for them and skip them. Also skip fids
-         * currently being operated on.
-         */
-        if (f->ref || f->flags & FID_NON_RECLAIMABLE) {
-            continue;
-        }
-        /*
-         * if it is a recently referenced fid
-         * we leave the fid untouched and clear the
-         * reference bit. We come back to it later
-         * in the next iteration. (a simple LRU without
-         * moving list elements around)
-         */
-        if (f->flags & FID_REFERENCED) {
-            f->flags &= ~FID_REFERENCED;
-            continue;
-        }
-        /*
-         * Add fids to reclaim list.
-         */
-        if (f->fid_type == P9_FID_FILE) {
-            if (f->fs.fd != -1) {
-                /*
-                 * Up the reference count so that
-                 * a clunk request won't free this fid
-                 */
-                f->ref++;
-                f->rclm_lst = reclaim_list;
-                reclaim_list = f;
-                f->fs_reclaim.fd = f->fs.fd;
-                f->fs.fd = -1;
-                reclaim_count++;
-            }
-        } else if (f->fid_type == P9_FID_DIR) {
-            if (f->fs.dir != NULL) {
-                /*
-                 * Up the reference count so that
-                 * a clunk request won't free this fid
-                 */
-                f->ref++;
-                f->rclm_lst = reclaim_list;
-                reclaim_list = f;
-                f->fs_reclaim.dir = f->fs.dir;
-                f->fs.dir = NULL;
-                reclaim_count++;
-            }
-        }
-        if (reclaim_count >= open_fd_rc) {
-            break;
-        }
-    }
-    /*
-     * Now close the fid in reclaim list. Free them if they
-     * are already clunked.
-     */
-    while (reclaim_list) {
-        f = reclaim_list;
-        reclaim_list = f->rclm_lst;
-        if (f->fid_type == P9_FID_FILE) {
-            v9fs_co_close(pdu, &f->fs_reclaim);
-        } else if (f->fid_type == P9_FID_DIR) {
-            v9fs_co_closedir(pdu, &f->fs_reclaim);
-        }
-        f->rclm_lst = NULL;
-        /*
-         * Now drop the fid reference, free it
-         * if clunked.
-         */
-        put_fid(pdu, f);
-    }
-}
-
-static int v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
-{
-    int err;
-    V9fsState *s = pdu->s;
-    V9fsFidState *fidp, head_fid;
-
-    head_fid.next = s->fid_list;
-    for (fidp = s->fid_list; fidp; fidp = fidp->next) {
-        if (fidp->path.size != path->size) {
-            continue;
-        }
-        if (!memcmp(fidp->path.data, path->data, path->size)) {
-            /* Mark the fid non reclaimable. */
-            fidp->flags |= FID_NON_RECLAIMABLE;
-
-            /* reopen the file/dir if already closed */
-            err = v9fs_reopen_fid(pdu, fidp);
-            if (err < 0) {
-                return -1;
-            }
-            /*
-             * Go back to head of fid list because
-             * the list could have got updated when
-             * switched to the worker thread
-             */
-            if (err == 0) {
-                fidp = &head_fid;
-            }
-        }
-    }
-    return 0;
-}
-
-static void virtfs_reset(V9fsPDU *pdu)
-{
-    V9fsState *s = pdu->s;
-    V9fsFidState *fidp = NULL;
-
-    /* Free all fids */
-    while (s->fid_list) {
-        fidp = s->fid_list;
-        s->fid_list = fidp->next;
-
-        if (fidp->ref) {
-            fidp->clunked = 1;
-        } else {
-            free_fid(pdu, fidp);
-        }
-    }
-    if (fidp) {
-        /* One or more unclunked fids found... */
-        error_report("9pfs:%s: One or more uncluncked fids "
-                     "found during reset", __func__);
-    }
-}
-
-#define P9_QID_TYPE_DIR         0x80
-#define P9_QID_TYPE_SYMLINK     0x02
-
-#define P9_STAT_MODE_DIR        0x80000000
-#define P9_STAT_MODE_APPEND     0x40000000
-#define P9_STAT_MODE_EXCL       0x20000000
-#define P9_STAT_MODE_MOUNT      0x10000000
-#define P9_STAT_MODE_AUTH       0x08000000
-#define P9_STAT_MODE_TMP        0x04000000
-#define P9_STAT_MODE_SYMLINK    0x02000000
-#define P9_STAT_MODE_LINK       0x01000000
-#define P9_STAT_MODE_DEVICE     0x00800000
-#define P9_STAT_MODE_NAMED_PIPE 0x00200000
-#define P9_STAT_MODE_SOCKET     0x00100000
-#define P9_STAT_MODE_SETUID     0x00080000
-#define P9_STAT_MODE_SETGID     0x00040000
-#define P9_STAT_MODE_SETVTX     0x00010000
-
-#define P9_STAT_MODE_TYPE_BITS (P9_STAT_MODE_DIR |          \
-                                P9_STAT_MODE_SYMLINK |      \
-                                P9_STAT_MODE_LINK |         \
-                                P9_STAT_MODE_DEVICE |       \
-                                P9_STAT_MODE_NAMED_PIPE |   \
-                                P9_STAT_MODE_SOCKET)
-
-/* This is the algorithm from ufs in spfs */
-static void stat_to_qid(const struct stat *stbuf, V9fsQID *qidp)
-{
-    size_t size;
-
-    memset(&qidp->path, 0, sizeof(qidp->path));
-    size = MIN(sizeof(stbuf->st_ino), sizeof(qidp->path));
-    memcpy(&qidp->path, &stbuf->st_ino, size);
-    qidp->version = stbuf->st_mtime ^ (stbuf->st_size << 8);
-    qidp->type = 0;
-    if (S_ISDIR(stbuf->st_mode)) {
-        qidp->type |= P9_QID_TYPE_DIR;
-    }
-    if (S_ISLNK(stbuf->st_mode)) {
-        qidp->type |= P9_QID_TYPE_SYMLINK;
-    }
-}
-
-static int fid_to_qid(V9fsPDU *pdu, V9fsFidState *fidp, V9fsQID *qidp)
-{
-    struct stat stbuf;
-    int err;
-
-    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-    if (err < 0) {
-        return err;
-    }
-    stat_to_qid(&stbuf, qidp);
-    return 0;
-}
-
-V9fsPDU *pdu_alloc(V9fsState *s)
-{
-    V9fsPDU *pdu = NULL;
-
-    if (!QLIST_EMPTY(&s->free_list)) {
-        pdu = QLIST_FIRST(&s->free_list);
-        QLIST_REMOVE(pdu, next);
-        QLIST_INSERT_HEAD(&s->active_list, pdu, next);
-    }
-    return pdu;
-}
-
-void pdu_free(V9fsPDU *pdu)
-{
-    if (pdu) {
-        V9fsState *s = pdu->s;
-        /*
-         * Cancelled pdu are added back to the freelist
-         * by flush request .
-         */
-        if (!pdu->cancelled) {
-            QLIST_REMOVE(pdu, next);
-            QLIST_INSERT_HEAD(&s->free_list, pdu, next);
-        }
-    }
-}
-
-/*
- * We don't do error checking for pdu_marshal/unmarshal here
- * because we always expect to have enough space to encode
- * error details
- */
-static void pdu_complete(V9fsPDU *pdu, ssize_t len)
-{
-    int8_t id = pdu->id + 1; /* Response */
-    V9fsState *s = pdu->s;
-
-    if (len < 0) {
-        int err = -len;
-        len = 7;
-
-        if (s->proto_version != V9FS_PROTO_2000L) {
-            V9fsString str;
-
-            str.data = strerror(err);
-            str.size = strlen(str.data);
-
-            len += pdu_marshal(pdu, len, "s", &str);
-            id = P9_RERROR;
-        }
-
-        len += pdu_marshal(pdu, len, "d", err);
-
-        if (s->proto_version == V9FS_PROTO_2000L) {
-            id = P9_RLERROR;
-        }
-        trace_v9fs_rerror(pdu->tag, pdu->id, err); /* Trace ERROR */
-    }
-
-    /* fill out the header */
-    pdu_marshal(pdu, 0, "dbw", (int32_t)len, id, pdu->tag);
-
-    /* keep these in sync */
-    pdu->size = len;
-    pdu->id = id;
-
-    pdu_push_and_notify(pdu);
-
-    /* Now wakeup anybody waiting in flush for this request */
-    qemu_co_queue_next(&pdu->complete);
-
-    pdu_free(pdu);
-}
-
-static mode_t v9mode_to_mode(uint32_t mode, V9fsString *extension)
-{
-    mode_t ret;
-
-    ret = mode & 0777;
-    if (mode & P9_STAT_MODE_DIR) {
-        ret |= S_IFDIR;
-    }
-
-    if (mode & P9_STAT_MODE_SYMLINK) {
-        ret |= S_IFLNK;
-    }
-    if (mode & P9_STAT_MODE_SOCKET) {
-        ret |= S_IFSOCK;
-    }
-    if (mode & P9_STAT_MODE_NAMED_PIPE) {
-        ret |= S_IFIFO;
-    }
-    if (mode & P9_STAT_MODE_DEVICE) {
-        if (extension->size && extension->data[0] == 'c') {
-            ret |= S_IFCHR;
-        } else {
-            ret |= S_IFBLK;
-        }
-    }
-
-    if (!(ret&~0777)) {
-        ret |= S_IFREG;
-    }
-
-    if (mode & P9_STAT_MODE_SETUID) {
-        ret |= S_ISUID;
-    }
-    if (mode & P9_STAT_MODE_SETGID) {
-        ret |= S_ISGID;
-    }
-    if (mode & P9_STAT_MODE_SETVTX) {
-        ret |= S_ISVTX;
-    }
-
-    return ret;
-}
-
-static int donttouch_stat(V9fsStat *stat)
-{
-    if (stat->type == -1 &&
-        stat->dev == -1 &&
-        stat->qid.type == -1 &&
-        stat->qid.version == -1 &&
-        stat->qid.path == -1 &&
-        stat->mode == -1 &&
-        stat->atime == -1 &&
-        stat->mtime == -1 &&
-        stat->length == -1 &&
-        !stat->name.size &&
-        !stat->uid.size &&
-        !stat->gid.size &&
-        !stat->muid.size &&
-        stat->n_uid == -1 &&
-        stat->n_gid == -1 &&
-        stat->n_muid == -1) {
-        return 1;
-    }
-
-    return 0;
-}
-
-static void v9fs_stat_init(V9fsStat *stat)
-{
-    v9fs_string_init(&stat->name);
-    v9fs_string_init(&stat->uid);
-    v9fs_string_init(&stat->gid);
-    v9fs_string_init(&stat->muid);
-    v9fs_string_init(&stat->extension);
-}
-
-static void v9fs_stat_free(V9fsStat *stat)
-{
-    v9fs_string_free(&stat->name);
-    v9fs_string_free(&stat->uid);
-    v9fs_string_free(&stat->gid);
-    v9fs_string_free(&stat->muid);
-    v9fs_string_free(&stat->extension);
-}
-
-static uint32_t stat_to_v9mode(const struct stat *stbuf)
-{
-    uint32_t mode;
-
-    mode = stbuf->st_mode & 0777;
-    if (S_ISDIR(stbuf->st_mode)) {
-        mode |= P9_STAT_MODE_DIR;
-    }
-
-    if (S_ISLNK(stbuf->st_mode)) {
-        mode |= P9_STAT_MODE_SYMLINK;
-    }
-
-    if (S_ISSOCK(stbuf->st_mode)) {
-        mode |= P9_STAT_MODE_SOCKET;
-    }
-
-    if (S_ISFIFO(stbuf->st_mode)) {
-        mode |= P9_STAT_MODE_NAMED_PIPE;
-    }
-
-    if (S_ISBLK(stbuf->st_mode) || S_ISCHR(stbuf->st_mode)) {
-        mode |= P9_STAT_MODE_DEVICE;
-    }
-
-    if (stbuf->st_mode & S_ISUID) {
-        mode |= P9_STAT_MODE_SETUID;
-    }
-
-    if (stbuf->st_mode & S_ISGID) {
-        mode |= P9_STAT_MODE_SETGID;
-    }
-
-    if (stbuf->st_mode & S_ISVTX) {
-        mode |= P9_STAT_MODE_SETVTX;
-    }
-
-    return mode;
-}
-
-static int stat_to_v9stat(V9fsPDU *pdu, V9fsPath *name,
-                            const struct stat *stbuf,
-                            V9fsStat *v9stat)
-{
-    int err;
-    const char *str;
-
-    memset(v9stat, 0, sizeof(*v9stat));
-
-    stat_to_qid(stbuf, &v9stat->qid);
-    v9stat->mode = stat_to_v9mode(stbuf);
-    v9stat->atime = stbuf->st_atime;
-    v9stat->mtime = stbuf->st_mtime;
-    v9stat->length = stbuf->st_size;
-
-    v9fs_string_null(&v9stat->uid);
-    v9fs_string_null(&v9stat->gid);
-    v9fs_string_null(&v9stat->muid);
-
-    v9stat->n_uid = stbuf->st_uid;
-    v9stat->n_gid = stbuf->st_gid;
-    v9stat->n_muid = 0;
-
-    v9fs_string_null(&v9stat->extension);
-
-    if (v9stat->mode & P9_STAT_MODE_SYMLINK) {
-        err = v9fs_co_readlink(pdu, name, &v9stat->extension);
-        if (err < 0) {
-            return err;
-        }
-    } else if (v9stat->mode & P9_STAT_MODE_DEVICE) {
-        v9fs_string_sprintf(&v9stat->extension, "%c %u %u",
-                S_ISCHR(stbuf->st_mode) ? 'c' : 'b',
-                major(stbuf->st_rdev), minor(stbuf->st_rdev));
-    } else if (S_ISDIR(stbuf->st_mode) || S_ISREG(stbuf->st_mode)) {
-        v9fs_string_sprintf(&v9stat->extension, "%s %lu",
-                "HARDLINKCOUNT", (unsigned long)stbuf->st_nlink);
-    }
-
-    str = strrchr(name->data, '/');
-    if (str) {
-        str += 1;
-    } else {
-        str = name->data;
-    }
-
-    v9fs_string_sprintf(&v9stat->name, "%s", str);
-
-    v9stat->size = 61 +
-        v9fs_string_size(&v9stat->name) +
-        v9fs_string_size(&v9stat->uid) +
-        v9fs_string_size(&v9stat->gid) +
-        v9fs_string_size(&v9stat->muid) +
-        v9fs_string_size(&v9stat->extension);
-    return 0;
-}
-
-#define P9_STATS_MODE          0x00000001ULL
-#define P9_STATS_NLINK         0x00000002ULL
-#define P9_STATS_UID           0x00000004ULL
-#define P9_STATS_GID           0x00000008ULL
-#define P9_STATS_RDEV          0x00000010ULL
-#define P9_STATS_ATIME         0x00000020ULL
-#define P9_STATS_MTIME         0x00000040ULL
-#define P9_STATS_CTIME         0x00000080ULL
-#define P9_STATS_INO           0x00000100ULL
-#define P9_STATS_SIZE          0x00000200ULL
-#define P9_STATS_BLOCKS        0x00000400ULL
-
-#define P9_STATS_BTIME         0x00000800ULL
-#define P9_STATS_GEN           0x00001000ULL
-#define P9_STATS_DATA_VERSION  0x00002000ULL
-
-#define P9_STATS_BASIC         0x000007ffULL /* Mask for fields up to BLOCKS */
-#define P9_STATS_ALL           0x00003fffULL /* Mask for All fields above */
-
-
-static void stat_to_v9stat_dotl(V9fsState *s, const struct stat *stbuf,
-                                V9fsStatDotl *v9lstat)
-{
-    memset(v9lstat, 0, sizeof(*v9lstat));
-
-    v9lstat->st_mode = stbuf->st_mode;
-    v9lstat->st_nlink = stbuf->st_nlink;
-    v9lstat->st_uid = stbuf->st_uid;
-    v9lstat->st_gid = stbuf->st_gid;
-    v9lstat->st_rdev = stbuf->st_rdev;
-    v9lstat->st_size = stbuf->st_size;
-    v9lstat->st_blksize = stbuf->st_blksize;
-    v9lstat->st_blocks = stbuf->st_blocks;
-    v9lstat->st_atime_sec = stbuf->st_atime;
-    v9lstat->st_atime_nsec = stbuf->st_atim.tv_nsec;
-    v9lstat->st_mtime_sec = stbuf->st_mtime;
-    v9lstat->st_mtime_nsec = stbuf->st_mtim.tv_nsec;
-    v9lstat->st_ctime_sec = stbuf->st_ctime;
-    v9lstat->st_ctime_nsec = stbuf->st_ctim.tv_nsec;
-    /* Currently we only support BASIC fields in stat */
-    v9lstat->st_result_mask = P9_STATS_BASIC;
-
-    stat_to_qid(stbuf, &v9lstat->qid);
-}
-
-static void print_sg(struct iovec *sg, int cnt)
-{
-    int i;
-
-    printf("sg[%d]: {", cnt);
-    for (i = 0; i < cnt; i++) {
-        if (i) {
-            printf(", ");
-        }
-        printf("(%p, %zd)", sg[i].iov_base, sg[i].iov_len);
-    }
-    printf("}\n");
-}
-
-/* Will call this only for path name based fid */
-static void v9fs_fix_path(V9fsPath *dst, V9fsPath *src, int len)
-{
-    V9fsPath str;
-    v9fs_path_init(&str);
-    v9fs_path_copy(&str, dst);
-    v9fs_string_sprintf((V9fsString *)dst, "%s%s", src->data, str.data+len);
-    v9fs_path_free(&str);
-    /* +1 to include terminating NULL */
-    dst->size++;
-}
-
-static inline bool is_ro_export(FsContext *ctx)
-{
-    return ctx->export_flags & V9FS_RDONLY;
-}
-
-static void v9fs_version(void *opaque)
-{
-    ssize_t err;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-    V9fsString version;
-    size_t offset = 7;
-
-    v9fs_string_init(&version);
-    err = pdu_unmarshal(pdu, offset, "ds", &s->msize, &version);
-    if (err < 0) {
-        offset = err;
-        goto out;
-    }
-    trace_v9fs_version(pdu->tag, pdu->id, s->msize, version.data);
-
-    virtfs_reset(pdu);
-
-    if (!strcmp(version.data, "9P2000.u")) {
-        s->proto_version = V9FS_PROTO_2000U;
-    } else if (!strcmp(version.data, "9P2000.L")) {
-        s->proto_version = V9FS_PROTO_2000L;
-    } else {
-        v9fs_string_sprintf(&version, "unknown");
-    }
-
-    err = pdu_marshal(pdu, offset, "ds", s->msize, &version);
-    if (err < 0) {
-        offset = err;
-        goto out;
-    }
-    offset += err;
-    trace_v9fs_version_return(pdu->tag, pdu->id, s->msize, version.data);
-out:
-    pdu_complete(pdu, offset);
-    v9fs_string_free(&version);
-}
-
-static void v9fs_attach(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-    int32_t fid, afid, n_uname;
-    V9fsString uname, aname;
-    V9fsFidState *fidp;
-    size_t offset = 7;
-    V9fsQID qid;
-    ssize_t err;
-
-    v9fs_string_init(&uname);
-    v9fs_string_init(&aname);
-    err = pdu_unmarshal(pdu, offset, "ddssd", &fid,
-                        &afid, &uname, &aname, &n_uname);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_attach(pdu->tag, pdu->id, fid, afid, uname.data, aname.data);
-
-    fidp = alloc_fid(s, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    fidp->uid = n_uname;
-    err = v9fs_co_name_to_path(pdu, NULL, "/", &fidp->path);
-    if (err < 0) {
-        err = -EINVAL;
-        clunk_fid(s, fid);
-        goto out;
-    }
-    err = fid_to_qid(pdu, fidp, &qid);
-    if (err < 0) {
-        err = -EINVAL;
-        clunk_fid(s, fid);
-        goto out;
-    }
-    err = pdu_marshal(pdu, offset, "Q", &qid);
-    if (err < 0) {
-        clunk_fid(s, fid);
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_attach_return(pdu->tag, pdu->id,
-                             qid.type, qid.version, qid.path);
-    /*
-     * disable migration if we haven't done already.
-     * attach could get called multiple times for the same export.
-     */
-    if (!s->migration_blocker) {
-        s->root_fid = fid;
-        error_set(&s->migration_blocker, QERR_VIRTFS_FEATURE_BLOCKS_MIGRATION,
-                  s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
-        migrate_add_blocker(s->migration_blocker);
-    }
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&uname);
-    v9fs_string_free(&aname);
-}
-
-static void v9fs_stat(void *opaque)
-{
-    int32_t fid;
-    V9fsStat v9stat;
-    ssize_t err = 0;
-    size_t offset = 7;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-
-    err = pdu_unmarshal(pdu, offset, "d", &fid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_stat(pdu->tag, pdu->id, fid);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    err = stat_to_v9stat(pdu, &fidp->path, &stbuf, &v9stat);
-    if (err < 0) {
-        goto out;
-    }
-    err = pdu_marshal(pdu, offset, "wS", 0, &v9stat);
-    if (err < 0) {
-        v9fs_stat_free(&v9stat);
-        goto out;
-    }
-    trace_v9fs_stat_return(pdu->tag, pdu->id, v9stat.mode,
-                           v9stat.atime, v9stat.mtime, v9stat.length);
-    err += offset;
-    v9fs_stat_free(&v9stat);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static void v9fs_getattr(void *opaque)
-{
-    int32_t fid;
-    size_t offset = 7;
-    ssize_t retval = 0;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    uint64_t request_mask;
-    V9fsStatDotl v9stat_dotl;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    retval = pdu_unmarshal(pdu, offset, "dq", &fid, &request_mask);
-    if (retval < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_getattr(pdu->tag, pdu->id, fid, request_mask);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        retval = -ENOENT;
-        goto out_nofid;
-    }
-    /*
-     * Currently we only support BASIC fields in stat, so there is no
-     * need to look at request_mask.
-     */
-    retval = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-    if (retval < 0) {
-        goto out;
-    }
-    stat_to_v9stat_dotl(s, &stbuf, &v9stat_dotl);
-
-    /*  fill st_gen if requested and supported by underlying fs */
-    if (request_mask & P9_STATS_GEN) {
-        retval = v9fs_co_st_gen(pdu, &fidp->path, stbuf.st_mode, &v9stat_dotl);
-        if (retval < 0) {
-            goto out;
-        }
-        v9stat_dotl.st_result_mask |= P9_STATS_GEN;
-    }
-    retval = pdu_marshal(pdu, offset, "A", &v9stat_dotl);
-    if (retval < 0) {
-        goto out;
-    }
-    retval += offset;
-    trace_v9fs_getattr_return(pdu->tag, pdu->id, v9stat_dotl.st_result_mask,
-                              v9stat_dotl.st_mode, v9stat_dotl.st_uid,
-                              v9stat_dotl.st_gid);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, retval);
-}
-
-/* Attribute flags */
-#define P9_ATTR_MODE       (1 << 0)
-#define P9_ATTR_UID        (1 << 1)
-#define P9_ATTR_GID        (1 << 2)
-#define P9_ATTR_SIZE       (1 << 3)
-#define P9_ATTR_ATIME      (1 << 4)
-#define P9_ATTR_MTIME      (1 << 5)
-#define P9_ATTR_CTIME      (1 << 6)
-#define P9_ATTR_ATIME_SET  (1 << 7)
-#define P9_ATTR_MTIME_SET  (1 << 8)
-
-#define P9_ATTR_MASK    127
-
-static void v9fs_setattr(void *opaque)
-{
-    int err = 0;
-    int32_t fid;
-    V9fsFidState *fidp;
-    size_t offset = 7;
-    V9fsIattr v9iattr;
-    V9fsPDU *pdu = opaque;
-
-    err = pdu_unmarshal(pdu, offset, "dI", &fid, &v9iattr);
-    if (err < 0) {
-        goto out_nofid;
-    }
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    if (v9iattr.valid & P9_ATTR_MODE) {
-        err = v9fs_co_chmod(pdu, &fidp->path, v9iattr.mode);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9iattr.valid & (P9_ATTR_ATIME | P9_ATTR_MTIME)) {
-        struct timespec times[2];
-        if (v9iattr.valid & P9_ATTR_ATIME) {
-            if (v9iattr.valid & P9_ATTR_ATIME_SET) {
-                times[0].tv_sec = v9iattr.atime_sec;
-                times[0].tv_nsec = v9iattr.atime_nsec;
-            } else {
-                times[0].tv_nsec = UTIME_NOW;
-            }
-        } else {
-            times[0].tv_nsec = UTIME_OMIT;
-        }
-        if (v9iattr.valid & P9_ATTR_MTIME) {
-            if (v9iattr.valid & P9_ATTR_MTIME_SET) {
-                times[1].tv_sec = v9iattr.mtime_sec;
-                times[1].tv_nsec = v9iattr.mtime_nsec;
-            } else {
-                times[1].tv_nsec = UTIME_NOW;
-            }
-        } else {
-            times[1].tv_nsec = UTIME_OMIT;
-        }
-        err = v9fs_co_utimensat(pdu, &fidp->path, times);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    /*
-     * If the only valid entry in iattr is ctime we can call
-     * chown(-1,-1) to update the ctime of the file
-     */
-    if ((v9iattr.valid & (P9_ATTR_UID | P9_ATTR_GID)) ||
-        ((v9iattr.valid & P9_ATTR_CTIME)
-         && !((v9iattr.valid & P9_ATTR_MASK) & ~P9_ATTR_CTIME))) {
-        if (!(v9iattr.valid & P9_ATTR_UID)) {
-            v9iattr.uid = -1;
-        }
-        if (!(v9iattr.valid & P9_ATTR_GID)) {
-            v9iattr.gid = -1;
-        }
-        err = v9fs_co_chown(pdu, &fidp->path, v9iattr.uid,
-                            v9iattr.gid);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9iattr.valid & (P9_ATTR_SIZE)) {
-        err = v9fs_co_truncate(pdu, &fidp->path, v9iattr.size);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    err = offset;
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static int v9fs_walk_marshal(V9fsPDU *pdu, uint16_t nwnames, V9fsQID *qids)
-{
-    int i;
-    ssize_t err;
-    size_t offset = 7;
-
-    err = pdu_marshal(pdu, offset, "w", nwnames);
-    if (err < 0) {
-        return err;
-    }
-    offset += err;
-    for (i = 0; i < nwnames; i++) {
-        err = pdu_marshal(pdu, offset, "Q", &qids[i]);
-        if (err < 0) {
-            return err;
-        }
-        offset += err;
-    }
-    return offset;
-}
-
-static void v9fs_walk(void *opaque)
-{
-    int name_idx;
-    V9fsQID *qids = NULL;
-    int i, err = 0;
-    V9fsPath dpath, path;
-    uint16_t nwnames;
-    struct stat stbuf;
-    size_t offset = 7;
-    int32_t fid, newfid;
-    V9fsString *wnames = NULL;
-    V9fsFidState *fidp;
-    V9fsFidState *newfidp = NULL;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    err = pdu_unmarshal(pdu, offset, "ddw", &fid, &newfid, &nwnames);
-    if (err < 0) {
-        pdu_complete(pdu, err);
-        return ;
-    }
-    offset += err;
-
-    trace_v9fs_walk(pdu->tag, pdu->id, fid, newfid, nwnames);
-
-    if (nwnames && nwnames <= P9_MAXWELEM) {
-        wnames = g_malloc0(sizeof(wnames[0]) * nwnames);
-        qids   = g_malloc0(sizeof(qids[0]) * nwnames);
-        for (i = 0; i < nwnames; i++) {
-            err = pdu_unmarshal(pdu, offset, "s", &wnames[i]);
-            if (err < 0) {
-                goto out_nofid;
-            }
-            offset += err;
-        }
-    } else if (nwnames > P9_MAXWELEM) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    v9fs_path_init(&dpath);
-    v9fs_path_init(&path);
-    /*
-     * Both dpath and path initially poin to fidp.
-     * Needed to handle request with nwnames == 0
-     */
-    v9fs_path_copy(&dpath, &fidp->path);
-    v9fs_path_copy(&path, &fidp->path);
-    for (name_idx = 0; name_idx < nwnames; name_idx++) {
-        err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_lstat(pdu, &path, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        stat_to_qid(&stbuf, &qids[name_idx]);
-        v9fs_path_copy(&dpath, &path);
-    }
-    if (fid == newfid) {
-        BUG_ON(fidp->fid_type != P9_FID_NONE);
-        v9fs_path_copy(&fidp->path, &path);
-    } else {
-        newfidp = alloc_fid(s, newfid);
-        if (newfidp == NULL) {
-            err = -EINVAL;
-            goto out;
-        }
-        newfidp->uid = fidp->uid;
-        v9fs_path_copy(&newfidp->path, &path);
-    }
-    err = v9fs_walk_marshal(pdu, nwnames, qids);
-    trace_v9fs_walk_return(pdu->tag, pdu->id, nwnames, qids);
-out:
-    put_fid(pdu, fidp);
-    if (newfidp) {
-        put_fid(pdu, newfidp);
-    }
-    v9fs_path_free(&dpath);
-    v9fs_path_free(&path);
-out_nofid:
-    pdu_complete(pdu, err);
-    if (nwnames && nwnames <= P9_MAXWELEM) {
-        for (name_idx = 0; name_idx < nwnames; name_idx++) {
-            v9fs_string_free(&wnames[name_idx]);
-        }
-        g_free(wnames);
-        g_free(qids);
-    }
-}
-
-static int32_t get_iounit(V9fsPDU *pdu, V9fsPath *path)
-{
-    struct statfs stbuf;
-    int32_t iounit = 0;
-    V9fsState *s = pdu->s;
-
-    /*
-     * iounit should be multiples of f_bsize (host filesystem block size
-     * and as well as less than (client msize - P9_IOHDRSZ))
-     */
-    if (!v9fs_co_statfs(pdu, path, &stbuf)) {
-        iounit = stbuf.f_bsize;
-        iounit *= (s->msize - P9_IOHDRSZ)/stbuf.f_bsize;
-    }
-    if (!iounit) {
-        iounit = s->msize - P9_IOHDRSZ;
-    }
-    return iounit;
-}
-
-static void v9fs_open(void *opaque)
-{
-    int flags;
-    int32_t fid;
-    int32_t mode;
-    V9fsQID qid;
-    int iounit = 0;
-    ssize_t err = 0;
-    size_t offset = 7;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    if (s->proto_version == V9FS_PROTO_2000L) {
-        err = pdu_unmarshal(pdu, offset, "dd", &fid, &mode);
-    } else {
-        uint8_t modebyte;
-        err = pdu_unmarshal(pdu, offset, "db", &fid, &modebyte);
-        mode = modebyte;
-    }
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_open(pdu->tag, pdu->id, fid, mode);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    BUG_ON(fidp->fid_type != P9_FID_NONE);
-
-    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    stat_to_qid(&stbuf, &qid);
-    if (S_ISDIR(stbuf.st_mode)) {
-        err = v9fs_co_opendir(pdu, fidp);
-        if (err < 0) {
-            goto out;
-        }
-        fidp->fid_type = P9_FID_DIR;
-        err = pdu_marshal(pdu, offset, "Qd", &qid, 0);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset;
-    } else {
-        if (s->proto_version == V9FS_PROTO_2000L) {
-            flags = get_dotl_openflags(s, mode);
-        } else {
-            flags = omode_to_uflags(mode);
-        }
-        if (is_ro_export(&s->ctx)) {
-            if (mode & O_WRONLY || mode & O_RDWR ||
-                mode & O_APPEND || mode & O_TRUNC) {
-                err = -EROFS;
-                goto out;
-            }
-        }
-        err = v9fs_co_open(pdu, fidp, flags);
-        if (err < 0) {
-            goto out;
-        }
-        fidp->fid_type = P9_FID_FILE;
-        fidp->open_flags = flags;
-        if (flags & O_EXCL) {
-            /*
-             * We let the host file system do O_EXCL check
-             * We should not reclaim such fd
-             */
-            fidp->flags |= FID_NON_RECLAIMABLE;
-        }
-        iounit = get_iounit(pdu, &fidp->path);
-        err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset;
-    }
-    trace_v9fs_open_return(pdu->tag, pdu->id,
-                           qid.type, qid.version, qid.path, iounit);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static void v9fs_lcreate(void *opaque)
-{
-    int32_t dfid, flags, mode;
-    gid_t gid;
-    ssize_t err = 0;
-    ssize_t offset = 7;
-    V9fsString name;
-    V9fsFidState *fidp;
-    struct stat stbuf;
-    V9fsQID qid;
-    int32_t iounit;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dsddd", &dfid,
-                        &name, &flags, &mode, &gid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_lcreate(pdu->tag, pdu->id, dfid, flags, mode, gid);
-
-    fidp = get_fid(pdu, dfid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-
-    flags = get_dotl_openflags(pdu->s, flags);
-    err = v9fs_co_open2(pdu, fidp, &name, gid,
-                        flags | O_CREAT, mode, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    fidp->fid_type = P9_FID_FILE;
-    fidp->open_flags = flags;
-    if (flags & O_EXCL) {
-        /*
-         * We let the host file system do O_EXCL check
-         * We should not reclaim such fd
-         */
-        fidp->flags |= FID_NON_RECLAIMABLE;
-    }
-    iounit =  get_iounit(pdu, &fidp->path);
-    stat_to_qid(&stbuf, &qid);
-    err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_lcreate_return(pdu->tag, pdu->id,
-                              qid.type, qid.version, qid.path, iounit);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-static void v9fs_fsync(void *opaque)
-{
-    int err;
-    int32_t fid;
-    int datasync;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-
-    err = pdu_unmarshal(pdu, offset, "dd", &fid, &datasync);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_fsync(pdu->tag, pdu->id, fid, datasync);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_fsync(pdu, fidp, datasync);
-    if (!err) {
-        err = offset;
-    }
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static void v9fs_clunk(void *opaque)
-{
-    int err;
-    int32_t fid;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    err = pdu_unmarshal(pdu, offset, "d", &fid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_clunk(pdu->tag, pdu->id, fid);
-
-    fidp = clunk_fid(s, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    /*
-     * Bump the ref so that put_fid will
-     * free the fid.
-     */
-    fidp->ref++;
-    err = put_fid(pdu, fidp);
-    if (!err) {
-        err = offset;
-    }
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static int v9fs_xattr_read(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
-                           uint64_t off, uint32_t max_count)
-{
-    ssize_t err;
-    size_t offset = 7;
-    int read_count;
-    int64_t xattr_len;
-
-    xattr_len = fidp->fs.xattr.len;
-    read_count = xattr_len - off;
-    if (read_count > max_count) {
-        read_count = max_count;
-    } else if (read_count < 0) {
-        /*
-         * read beyond XATTR value
-         */
-        read_count = 0;
-    }
-    err = pdu_marshal(pdu, offset, "d", read_count);
-    if (err < 0) {
-        return err;
-    }
-    offset += err;
-    err = v9fs_pack(pdu->elem.in_sg, pdu->elem.in_num, offset,
-                    ((char *)fidp->fs.xattr.value) + off,
-                    read_count);
-    if (err < 0) {
-        return err;
-    }
-    offset += err;
-    return offset;
-}
-
-static int v9fs_do_readdir_with_stat(V9fsPDU *pdu,
-                                     V9fsFidState *fidp, uint32_t max_count)
-{
-    V9fsPath path;
-    V9fsStat v9stat;
-    int len, err = 0;
-    int32_t count = 0;
-    struct stat stbuf;
-    off_t saved_dir_pos;
-    struct dirent *dent, *result;
-
-    /* save the directory position */
-    saved_dir_pos = v9fs_co_telldir(pdu, fidp);
-    if (saved_dir_pos < 0) {
-        return saved_dir_pos;
-    }
-
-    dent = g_malloc(sizeof(struct dirent));
-
-    while (1) {
-        v9fs_path_init(&path);
-        err = v9fs_co_readdir_r(pdu, fidp, dent, &result);
-        if (err || !result) {
-            break;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, dent->d_name, &path);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_lstat(pdu, &path, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = stat_to_v9stat(pdu, &path, &stbuf, &v9stat);
-        if (err < 0) {
-            goto out;
-        }
-        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
-        len = pdu_marshal(pdu, 11 + count, "S", &v9stat);
-        if ((len != (v9stat.size + 2)) || ((count + len) > max_count)) {
-            /* Ran out of buffer. Set dir back to old position and return */
-            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
-            v9fs_stat_free(&v9stat);
-            v9fs_path_free(&path);
-            g_free(dent);
-            return count;
-        }
-        count += len;
-        v9fs_stat_free(&v9stat);
-        v9fs_path_free(&path);
-        saved_dir_pos = dent->d_off;
-    }
-out:
-    g_free(dent);
-    v9fs_path_free(&path);
-    if (err < 0) {
-        return err;
-    }
-    return count;
-}
-
-/*
- * Create a QEMUIOVector for a sub-region of PDU iovecs
- *
- * @qiov:       uninitialized QEMUIOVector
- * @skip:       number of bytes to skip from beginning of PDU
- * @size:       number of bytes to include
- * @is_write:   true - write, false - read
- *
- * The resulting QEMUIOVector has heap-allocated iovecs and must be cleaned up
- * with qemu_iovec_destroy().
- */
-static void v9fs_init_qiov_from_pdu(QEMUIOVector *qiov, V9fsPDU *pdu,
-                                    size_t skip, size_t size,
-                                    bool is_write)
-{
-    QEMUIOVector elem;
-    struct iovec *iov;
-    unsigned int niov;
-
-    virtio_init_iov_from_pdu(pdu, &iov, &niov, is_write);
-
-    qemu_iovec_init_external(&elem, iov, niov);
-    qemu_iovec_init(qiov, niov);
-    qemu_iovec_concat(qiov, &elem, skip, size);
-}
-
-static void v9fs_read(void *opaque)
-{
-    int32_t fid;
-    uint64_t off;
-    ssize_t err = 0;
-    int32_t count = 0;
-    size_t offset = 7;
-    uint32_t max_count;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    err = pdu_unmarshal(pdu, offset, "dqd", &fid, &off, &max_count);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_read(pdu->tag, pdu->id, fid, off, max_count);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    if (fidp->fid_type == P9_FID_DIR) {
-
-        if (off == 0) {
-            v9fs_co_rewinddir(pdu, fidp);
-        }
-        count = v9fs_do_readdir_with_stat(pdu, fidp, max_count);
-        if (count < 0) {
-            err = count;
-            goto out;
-        }
-        err = pdu_marshal(pdu, offset, "d", count);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset + count;
-    } else if (fidp->fid_type == P9_FID_FILE) {
-        QEMUIOVector qiov_full;
-        QEMUIOVector qiov;
-        int32_t len;
-
-        v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset + 4, max_count, false);
-        qemu_iovec_init(&qiov, qiov_full.niov);
-        do {
-            qemu_iovec_reset(&qiov);
-            qemu_iovec_concat(&qiov, &qiov_full, count, qiov_full.size - count);
-            if (0) {
-                print_sg(qiov.iov, qiov.niov);
-            }
-            /* Loop in case of EINTR */
-            do {
-                len = v9fs_co_preadv(pdu, fidp, qiov.iov, qiov.niov, off);
-                if (len >= 0) {
-                    off   += len;
-                    count += len;
-                }
-            } while (len == -EINTR && !pdu->cancelled);
-            if (len < 0) {
-                /* IO error return the error */
-                err = len;
-                goto out;
-            }
-        } while (count < max_count && len > 0);
-        err = pdu_marshal(pdu, offset, "d", count);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset + count;
-        qemu_iovec_destroy(&qiov);
-        qemu_iovec_destroy(&qiov_full);
-    } else if (fidp->fid_type == P9_FID_XATTR) {
-        err = v9fs_xattr_read(s, pdu, fidp, off, max_count);
-    } else {
-        err = -EINVAL;
-    }
-    trace_v9fs_read_return(pdu->tag, pdu->id, count, err);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static size_t v9fs_readdir_data_size(V9fsString *name)
-{
-    /*
-     * Size of each dirent on the wire: size of qid (13) + size of offset (8)
-     * size of type (1) + size of name.size (2) + strlen(name.data)
-     */
-    return 24 + v9fs_string_size(name);
-}
-
-static int v9fs_do_readdir(V9fsPDU *pdu,
-                           V9fsFidState *fidp, int32_t max_count)
-{
-    size_t size;
-    V9fsQID qid;
-    V9fsString name;
-    int len, err = 0;
-    int32_t count = 0;
-    off_t saved_dir_pos;
-    struct dirent *dent, *result;
-
-    /* save the directory position */
-    saved_dir_pos = v9fs_co_telldir(pdu, fidp);
-    if (saved_dir_pos < 0) {
-        return saved_dir_pos;
-    }
-
-    dent = g_malloc(sizeof(struct dirent));
-
-    while (1) {
-        err = v9fs_co_readdir_r(pdu, fidp, dent, &result);
-        if (err || !result) {
-            break;
-        }
-        v9fs_string_init(&name);
-        v9fs_string_sprintf(&name, "%s", dent->d_name);
-        if ((count + v9fs_readdir_data_size(&name)) > max_count) {
-            /* Ran out of buffer. Set dir back to old position and return */
-            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
-            v9fs_string_free(&name);
-            g_free(dent);
-            return count;
-        }
-        /*
-         * Fill up just the path field of qid because the client uses
-         * only that. To fill the entire qid structure we will have
-         * to stat each dirent found, which is expensive
-         */
-        size = MIN(sizeof(dent->d_ino), sizeof(qid.path));
-        memcpy(&qid.path, &dent->d_ino, size);
-        /* Fill the other fields with dummy values */
-        qid.type = 0;
-        qid.version = 0;
-
-        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
-        len = pdu_marshal(pdu, 11 + count, "Qqbs",
-                          &qid, dent->d_off,
-                          dent->d_type, &name);
-        if (len < 0) {
-            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
-            v9fs_string_free(&name);
-            g_free(dent);
-            return len;
-        }
-        count += len;
-        v9fs_string_free(&name);
-        saved_dir_pos = dent->d_off;
-    }
-    g_free(dent);
-    if (err < 0) {
-        return err;
-    }
-    return count;
-}
-
-static void v9fs_readdir(void *opaque)
-{
-    int32_t fid;
-    V9fsFidState *fidp;
-    ssize_t retval = 0;
-    size_t offset = 7;
-    uint64_t initial_offset;
-    int32_t count;
-    uint32_t max_count;
-    V9fsPDU *pdu = opaque;
-
-    retval = pdu_unmarshal(pdu, offset, "dqd", &fid,
-                           &initial_offset, &max_count);
-    if (retval < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_readdir(pdu->tag, pdu->id, fid, initial_offset, max_count);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        retval = -EINVAL;
-        goto out_nofid;
-    }
-    if (!fidp->fs.dir) {
-        retval = -EINVAL;
-        goto out;
-    }
-    if (initial_offset == 0) {
-        v9fs_co_rewinddir(pdu, fidp);
-    } else {
-        v9fs_co_seekdir(pdu, fidp, initial_offset);
-    }
-    count = v9fs_do_readdir(pdu, fidp, max_count);
-    if (count < 0) {
-        retval = count;
-        goto out;
-    }
-    retval = pdu_marshal(pdu, offset, "d", count);
-    if (retval < 0) {
-        goto out;
-    }
-    retval += count + offset;
-    trace_v9fs_readdir_return(pdu->tag, pdu->id, count, retval);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, retval);
-}
-
-static int v9fs_xattr_write(V9fsState *s, V9fsPDU *pdu, V9fsFidState *fidp,
-                            uint64_t off, uint32_t count,
-                            struct iovec *sg, int cnt)
-{
-    int i, to_copy;
-    ssize_t err = 0;
-    int write_count;
-    int64_t xattr_len;
-    size_t offset = 7;
-
-
-    xattr_len = fidp->fs.xattr.len;
-    write_count = xattr_len - off;
-    if (write_count > count) {
-        write_count = count;
-    } else if (write_count < 0) {
-        /*
-         * write beyond XATTR value len specified in
-         * xattrcreate
-         */
-        err = -ENOSPC;
-        goto out;
-    }
-    err = pdu_marshal(pdu, offset, "d", write_count);
-    if (err < 0) {
-        return err;
-    }
-    err += offset;
-    fidp->fs.xattr.copied_len += write_count;
-    /*
-     * Now copy the content from sg list
-     */
-    for (i = 0; i < cnt; i++) {
-        if (write_count > sg[i].iov_len) {
-            to_copy = sg[i].iov_len;
-        } else {
-            to_copy = write_count;
-        }
-        memcpy((char *)fidp->fs.xattr.value + off, sg[i].iov_base, to_copy);
-        /* updating vs->off since we are not using below */
-        off += to_copy;
-        write_count -= to_copy;
-    }
-out:
-    return err;
-}
-
-static void v9fs_write(void *opaque)
-{
-    ssize_t err;
-    int32_t fid;
-    uint64_t off;
-    uint32_t count;
-    int32_t len = 0;
-    int32_t total = 0;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-    QEMUIOVector qiov_full;
-    QEMUIOVector qiov;
-
-    err = pdu_unmarshal(pdu, offset, "dqd", &fid, &off, &count);
-    if (err < 0) {
-        pdu_complete(pdu, err);
-        return;
-    }
-    offset += err;
-    v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset, count, true);
-    trace_v9fs_write(pdu->tag, pdu->id, fid, off, count, qiov_full.niov);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    if (fidp->fid_type == P9_FID_FILE) {
-        if (fidp->fs.fd == -1) {
-            err = -EINVAL;
-            goto out;
-        }
-    } else if (fidp->fid_type == P9_FID_XATTR) {
-        /*
-         * setxattr operation
-         */
-        err = v9fs_xattr_write(s, pdu, fidp, off, count,
-                               qiov_full.iov, qiov_full.niov);
-        goto out;
-    } else {
-        err = -EINVAL;
-        goto out;
-    }
-    qemu_iovec_init(&qiov, qiov_full.niov);
-    do {
-        qemu_iovec_reset(&qiov);
-        qemu_iovec_concat(&qiov, &qiov_full, total, qiov_full.size - total);
-        if (0) {
-            print_sg(qiov.iov, qiov.niov);
-        }
-        /* Loop in case of EINTR */
-        do {
-            len = v9fs_co_pwritev(pdu, fidp, qiov.iov, qiov.niov, off);
-            if (len >= 0) {
-                off   += len;
-                total += len;
-            }
-        } while (len == -EINTR && !pdu->cancelled);
-        if (len < 0) {
-            /* IO error return the error */
-            err = len;
-            goto out_qiov;
-        }
-    } while (total < count && len > 0);
-
-    offset = 7;
-    err = pdu_marshal(pdu, offset, "d", total);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_write_return(pdu->tag, pdu->id, total, err);
-out_qiov:
-    qemu_iovec_destroy(&qiov);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    qemu_iovec_destroy(&qiov_full);
-    pdu_complete(pdu, err);
-}
-
-static void v9fs_create(void *opaque)
-{
-    int32_t fid;
-    int err = 0;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    V9fsQID qid;
-    int32_t perm;
-    int8_t mode;
-    V9fsPath path;
-    struct stat stbuf;
-    V9fsString name;
-    V9fsString extension;
-    int iounit;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_path_init(&path);
-    v9fs_string_init(&name);
-    v9fs_string_init(&extension);
-    err = pdu_unmarshal(pdu, offset, "dsdbs", &fid, &name,
-                        &perm, &mode, &extension);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_create(pdu->tag, pdu->id, fid, name.data, perm, mode);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    if (perm & P9_STAT_MODE_DIR) {
-        err = v9fs_co_mkdir(pdu, fidp, &name, perm & 0777,
-                            fidp->uid, -1, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-        err = v9fs_co_opendir(pdu, fidp);
-        if (err < 0) {
-            goto out;
-        }
-        fidp->fid_type = P9_FID_DIR;
-    } else if (perm & P9_STAT_MODE_SYMLINK) {
-        err = v9fs_co_symlink(pdu, fidp, &name,
-                              extension.data, -1 , &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-    } else if (perm & P9_STAT_MODE_LINK) {
-        int32_t ofid = atoi(extension.data);
-        V9fsFidState *ofidp = get_fid(pdu, ofid);
-        if (ofidp == NULL) {
-            err = -EINVAL;
-            goto out;
-        }
-        err = v9fs_co_link(pdu, ofidp, fidp, &name);
-        put_fid(pdu, ofidp);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            fidp->fid_type = P9_FID_NONE;
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-        err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-        if (err < 0) {
-            fidp->fid_type = P9_FID_NONE;
-            goto out;
-        }
-    } else if (perm & P9_STAT_MODE_DEVICE) {
-        char ctype;
-        uint32_t major, minor;
-        mode_t nmode = 0;
-
-        if (sscanf(extension.data, "%c %u %u", &ctype, &major, &minor) != 3) {
-            err = -errno;
-            goto out;
-        }
-
-        switch (ctype) {
-        case 'c':
-            nmode = S_IFCHR;
-            break;
-        case 'b':
-            nmode = S_IFBLK;
-            break;
-        default:
-            err = -EIO;
-            goto out;
-        }
-
-        nmode |= perm & 0777;
-        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
-                            makedev(major, minor), nmode, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-    } else if (perm & P9_STAT_MODE_NAMED_PIPE) {
-        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
-                            0, S_IFIFO | (perm & 0777), &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-    } else if (perm & P9_STAT_MODE_SOCKET) {
-        err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, -1,
-                            0, S_IFSOCK | (perm & 0777), &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        err = v9fs_co_name_to_path(pdu, &fidp->path, name.data, &path);
-        if (err < 0) {
-            goto out;
-        }
-        v9fs_path_copy(&fidp->path, &path);
-    } else {
-        err = v9fs_co_open2(pdu, fidp, &name, -1,
-                            omode_to_uflags(mode)|O_CREAT, perm, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        fidp->fid_type = P9_FID_FILE;
-        fidp->open_flags = omode_to_uflags(mode);
-        if (fidp->open_flags & O_EXCL) {
-            /*
-             * We let the host file system do O_EXCL check
-             * We should not reclaim such fd
-             */
-            fidp->flags |= FID_NON_RECLAIMABLE;
-        }
-    }
-    iounit = get_iounit(pdu, &fidp->path);
-    stat_to_qid(&stbuf, &qid);
-    err = pdu_marshal(pdu, offset, "Qd", &qid, iounit);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_create_return(pdu->tag, pdu->id,
-                             qid.type, qid.version, qid.path, iounit);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-   pdu_complete(pdu, err);
-   v9fs_string_free(&name);
-   v9fs_string_free(&extension);
-   v9fs_path_free(&path);
-}
-
-static void v9fs_symlink(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    V9fsString name;
-    V9fsString symname;
-    V9fsFidState *dfidp;
-    V9fsQID qid;
-    struct stat stbuf;
-    int32_t dfid;
-    int err = 0;
-    gid_t gid;
-    size_t offset = 7;
-
-    v9fs_string_init(&name);
-    v9fs_string_init(&symname);
-    err = pdu_unmarshal(pdu, offset, "dssd", &dfid, &name, &symname, &gid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_symlink(pdu->tag, pdu->id, dfid, name.data, symname.data, gid);
-
-    dfidp = get_fid(pdu, dfid);
-    if (dfidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    err = v9fs_co_symlink(pdu, dfidp, &name, symname.data, gid, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    stat_to_qid(&stbuf, &qid);
-    err =  pdu_marshal(pdu, offset, "Q", &qid);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_symlink_return(pdu->tag, pdu->id,
-                              qid.type, qid.version, qid.path);
-out:
-    put_fid(pdu, dfidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-    v9fs_string_free(&symname);
-}
-
-static void v9fs_flush(void *opaque)
-{
-    ssize_t err;
-    int16_t tag;
-    size_t offset = 7;
-    V9fsPDU *cancel_pdu;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    err = pdu_unmarshal(pdu, offset, "w", &tag);
-    if (err < 0) {
-        pdu_complete(pdu, err);
-        return;
-    }
-    trace_v9fs_flush(pdu->tag, pdu->id, tag);
-
-    QLIST_FOREACH(cancel_pdu, &s->active_list, next) {
-        if (cancel_pdu->tag == tag) {
-            break;
-        }
-    }
-    if (cancel_pdu) {
-        cancel_pdu->cancelled = 1;
-        /*
-         * Wait for pdu to complete.
-         */
-        qemu_co_queue_wait(&cancel_pdu->complete);
-        cancel_pdu->cancelled = 0;
-        pdu_free(cancel_pdu);
-    }
-    pdu_complete(pdu, 7);
-}
-
-static void v9fs_link(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    int32_t dfid, oldfid;
-    V9fsFidState *dfidp, *oldfidp;
-    V9fsString name;
-    size_t offset = 7;
-    int err = 0;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dds", &dfid, &oldfid, &name);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_link(pdu->tag, pdu->id, dfid, oldfid, name.data);
-
-    dfidp = get_fid(pdu, dfid);
-    if (dfidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-
-    oldfidp = get_fid(pdu, oldfid);
-    if (oldfidp == NULL) {
-        err = -ENOENT;
-        goto out;
-    }
-    err = v9fs_co_link(pdu, oldfidp, dfidp, &name);
-    if (!err) {
-        err = offset;
-    }
-out:
-    put_fid(pdu, dfidp);
-out_nofid:
-    v9fs_string_free(&name);
-    pdu_complete(pdu, err);
-}
-
-/* Only works with path name based fid */
-static void v9fs_remove(void *opaque)
-{
-    int32_t fid;
-    int err = 0;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-
-    err = pdu_unmarshal(pdu, offset, "d", &fid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_remove(pdu->tag, pdu->id, fid);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    /* if fs driver is not path based, return EOPNOTSUPP */
-    if (!(pdu->s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT)) {
-        err = -EOPNOTSUPP;
-        goto out_err;
-    }
-    /*
-     * IF the file is unlinked, we cannot reopen
-     * the file later. So don't reclaim fd
-     */
-    err = v9fs_mark_fids_unreclaim(pdu, &fidp->path);
-    if (err < 0) {
-        goto out_err;
-    }
-    err = v9fs_co_remove(pdu, &fidp->path);
-    if (!err) {
-        err = offset;
-    }
-out_err:
-    /* For TREMOVE we need to clunk the fid even on failed remove */
-    clunk_fid(pdu->s, fidp->fid);
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static void v9fs_unlinkat(void *opaque)
-{
-    int err = 0;
-    V9fsString name;
-    int32_t dfid, flags;
-    size_t offset = 7;
-    V9fsPath path;
-    V9fsFidState *dfidp;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dsd", &dfid, &name, &flags);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    dfidp = get_fid(pdu, dfid);
-    if (dfidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    /*
-     * IF the file is unlinked, we cannot reopen
-     * the file later. So don't reclaim fd
-     */
-    v9fs_path_init(&path);
-    err = v9fs_co_name_to_path(pdu, &dfidp->path, name.data, &path);
-    if (err < 0) {
-        goto out_err;
-    }
-    err = v9fs_mark_fids_unreclaim(pdu, &path);
-    if (err < 0) {
-        goto out_err;
-    }
-    err = v9fs_co_unlinkat(pdu, &dfidp->path, &name, flags);
-    if (!err) {
-        err = offset;
-    }
-out_err:
-    put_fid(pdu, dfidp);
-    v9fs_path_free(&path);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-
-/* Only works with path name based fid */
-static int v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
-                                int32_t newdirfid, V9fsString *name)
-{
-    char *end;
-    int err = 0;
-    V9fsPath new_path;
-    V9fsFidState *tfidp;
-    V9fsState *s = pdu->s;
-    V9fsFidState *dirfidp = NULL;
-    char *old_name, *new_name;
-
-    v9fs_path_init(&new_path);
-    if (newdirfid != -1) {
-        dirfidp = get_fid(pdu, newdirfid);
-        if (dirfidp == NULL) {
-            err = -ENOENT;
-            goto out_nofid;
-        }
-        BUG_ON(dirfidp->fid_type != P9_FID_NONE);
-        v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path);
-    } else {
-        old_name = fidp->path.data;
-        end = strrchr(old_name, '/');
-        if (end) {
-            end++;
-        } else {
-            end = old_name;
-        }
-        new_name = g_malloc0(end - old_name + name->size + 1);
-        strncat(new_name, old_name, end - old_name);
-        strncat(new_name + (end - old_name), name->data, name->size);
-        v9fs_co_name_to_path(pdu, NULL, new_name, &new_path);
-        g_free(new_name);
-    }
-    err = v9fs_co_rename(pdu, &fidp->path, &new_path);
-    if (err < 0) {
-        goto out;
-    }
-    /*
-     * Fixup fid's pointing to the old name to
-     * start pointing to the new name
-     */
-    for (tfidp = s->fid_list; tfidp; tfidp = tfidp->next) {
-        if (v9fs_path_is_ancestor(&fidp->path, &tfidp->path)) {
-            /* replace the name */
-            v9fs_fix_path(&tfidp->path, &new_path, strlen(fidp->path.data));
-        }
-    }
-out:
-    if (dirfidp) {
-        put_fid(pdu, dirfidp);
-    }
-    v9fs_path_free(&new_path);
-out_nofid:
-    return err;
-}
-
-/* Only works with path name based fid */
-static void v9fs_rename(void *opaque)
-{
-    int32_t fid;
-    ssize_t err = 0;
-    size_t offset = 7;
-    V9fsString name;
-    int32_t newdirfid;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dds", &fid, &newdirfid, &name);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    BUG_ON(fidp->fid_type != P9_FID_NONE);
-    /* if fs driver is not path based, return EOPNOTSUPP */
-    if (!(pdu->s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT)) {
-        err = -EOPNOTSUPP;
-        goto out;
-    }
-    v9fs_path_write_lock(s);
-    err = v9fs_complete_rename(pdu, fidp, newdirfid, &name);
-    v9fs_path_unlock(s);
-    if (!err) {
-        err = offset;
-    }
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-static void v9fs_fix_fid_paths(V9fsPDU *pdu, V9fsPath *olddir,
-                               V9fsString *old_name, V9fsPath *newdir,
-                               V9fsString *new_name)
-{
-    V9fsFidState *tfidp;
-    V9fsPath oldpath, newpath;
-    V9fsState *s = pdu->s;
-
-
-    v9fs_path_init(&oldpath);
-    v9fs_path_init(&newpath);
-    v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath);
-    v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath);
-
-    /*
-     * Fixup fid's pointing to the old name to
-     * start pointing to the new name
-     */
-    for (tfidp = s->fid_list; tfidp; tfidp = tfidp->next) {
-        if (v9fs_path_is_ancestor(&oldpath, &tfidp->path)) {
-            /* replace the name */
-            v9fs_fix_path(&tfidp->path, &newpath, strlen(oldpath.data));
-        }
-    }
-    v9fs_path_free(&oldpath);
-    v9fs_path_free(&newpath);
-}
-
-static int v9fs_complete_renameat(V9fsPDU *pdu, int32_t olddirfid,
-                                  V9fsString *old_name, int32_t newdirfid,
-                                  V9fsString *new_name)
-{
-    int err = 0;
-    V9fsState *s = pdu->s;
-    V9fsFidState *newdirfidp = NULL, *olddirfidp = NULL;
-
-    olddirfidp = get_fid(pdu, olddirfid);
-    if (olddirfidp == NULL) {
-        err = -ENOENT;
-        goto out;
-    }
-    if (newdirfid != -1) {
-        newdirfidp = get_fid(pdu, newdirfid);
-        if (newdirfidp == NULL) {
-            err = -ENOENT;
-            goto out;
-        }
-    } else {
-        newdirfidp = get_fid(pdu, olddirfid);
-    }
-
-    err = v9fs_co_renameat(pdu, &olddirfidp->path, old_name,
-                           &newdirfidp->path, new_name);
-    if (err < 0) {
-        goto out;
-    }
-    if (s->ctx.export_flags & V9FS_PATHNAME_FSCONTEXT) {
-        /* Only for path based fid  we need to do the below fixup */
-        v9fs_fix_fid_paths(pdu, &olddirfidp->path, old_name,
-                           &newdirfidp->path, new_name);
-    }
-out:
-    if (olddirfidp) {
-        put_fid(pdu, olddirfidp);
-    }
-    if (newdirfidp) {
-        put_fid(pdu, newdirfidp);
-    }
-    return err;
-}
-
-static void v9fs_renameat(void *opaque)
-{
-    ssize_t err = 0;
-    size_t offset = 7;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-    int32_t olddirfid, newdirfid;
-    V9fsString old_name, new_name;
-
-    v9fs_string_init(&old_name);
-    v9fs_string_init(&new_name);
-    err = pdu_unmarshal(pdu, offset, "dsds", &olddirfid,
-                        &old_name, &newdirfid, &new_name);
-    if (err < 0) {
-        goto out_err;
-    }
-
-    v9fs_path_write_lock(s);
-    err = v9fs_complete_renameat(pdu, olddirfid,
-                                 &old_name, newdirfid, &new_name);
-    v9fs_path_unlock(s);
-    if (!err) {
-        err = offset;
-    }
-
-out_err:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&old_name);
-    v9fs_string_free(&new_name);
-}
-
-static void v9fs_wstat(void *opaque)
-{
-    int32_t fid;
-    int err = 0;
-    int16_t unused;
-    V9fsStat v9stat;
-    size_t offset = 7;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_stat_init(&v9stat);
-    err = pdu_unmarshal(pdu, offset, "dwS", &fid, &unused, &v9stat);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_wstat(pdu->tag, pdu->id, fid,
-                     v9stat.mode, v9stat.atime, v9stat.mtime);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    /* do we need to sync the file? */
-    if (donttouch_stat(&v9stat)) {
-        err = v9fs_co_fsync(pdu, fidp, 0);
-        goto out;
-    }
-    if (v9stat.mode != -1) {
-        uint32_t v9_mode;
-        err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
-        if (err < 0) {
-            goto out;
-        }
-        v9_mode = stat_to_v9mode(&stbuf);
-        if ((v9stat.mode & P9_STAT_MODE_TYPE_BITS) !=
-            (v9_mode & P9_STAT_MODE_TYPE_BITS)) {
-            /* Attempting to change the type */
-            err = -EIO;
-            goto out;
-        }
-        err = v9fs_co_chmod(pdu, &fidp->path,
-                            v9mode_to_mode(v9stat.mode,
-                                           &v9stat.extension));
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9stat.mtime != -1 || v9stat.atime != -1) {
-        struct timespec times[2];
-        if (v9stat.atime != -1) {
-            times[0].tv_sec = v9stat.atime;
-            times[0].tv_nsec = 0;
-        } else {
-            times[0].tv_nsec = UTIME_OMIT;
-        }
-        if (v9stat.mtime != -1) {
-            times[1].tv_sec = v9stat.mtime;
-            times[1].tv_nsec = 0;
-        } else {
-            times[1].tv_nsec = UTIME_OMIT;
-        }
-        err = v9fs_co_utimensat(pdu, &fidp->path, times);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9stat.n_gid != -1 || v9stat.n_uid != -1) {
-        err = v9fs_co_chown(pdu, &fidp->path, v9stat.n_uid, v9stat.n_gid);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9stat.name.size != 0) {
-        err = v9fs_complete_rename(pdu, fidp, -1, &v9stat.name);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    if (v9stat.length != -1) {
-        err = v9fs_co_truncate(pdu, &fidp->path, v9stat.length);
-        if (err < 0) {
-            goto out;
-        }
-    }
-    err = offset;
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    v9fs_stat_free(&v9stat);
-    pdu_complete(pdu, err);
-}
-
-static int v9fs_fill_statfs(V9fsState *s, V9fsPDU *pdu, struct statfs *stbuf)
-{
-    uint32_t f_type;
-    uint32_t f_bsize;
-    uint64_t f_blocks;
-    uint64_t f_bfree;
-    uint64_t f_bavail;
-    uint64_t f_files;
-    uint64_t f_ffree;
-    uint64_t fsid_val;
-    uint32_t f_namelen;
-    size_t offset = 7;
-    int32_t bsize_factor;
-
-    /*
-     * compute bsize factor based on host file system block size
-     * and client msize
-     */
-    bsize_factor = (s->msize - P9_IOHDRSZ)/stbuf->f_bsize;
-    if (!bsize_factor) {
-        bsize_factor = 1;
-    }
-    f_type  = stbuf->f_type;
-    f_bsize = stbuf->f_bsize;
-    f_bsize *= bsize_factor;
-    /*
-     * f_bsize is adjusted(multiplied) by bsize factor, so we need to
-     * adjust(divide) the number of blocks, free blocks and available
-     * blocks by bsize factor
-     */
-    f_blocks = stbuf->f_blocks/bsize_factor;
-    f_bfree  = stbuf->f_bfree/bsize_factor;
-    f_bavail = stbuf->f_bavail/bsize_factor;
-    f_files  = stbuf->f_files;
-    f_ffree  = stbuf->f_ffree;
-    fsid_val = (unsigned int) stbuf->f_fsid.__val[0] |
-               (unsigned long long)stbuf->f_fsid.__val[1] << 32;
-    f_namelen = stbuf->f_namelen;
-
-    return pdu_marshal(pdu, offset, "ddqqqqqqd",
-                       f_type, f_bsize, f_blocks, f_bfree,
-                       f_bavail, f_files, f_ffree,
-                       fsid_val, f_namelen);
-}
-
-static void v9fs_statfs(void *opaque)
-{
-    int32_t fid;
-    ssize_t retval = 0;
-    size_t offset = 7;
-    V9fsFidState *fidp;
-    struct statfs stbuf;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    retval = pdu_unmarshal(pdu, offset, "d", &fid);
-    if (retval < 0) {
-        goto out_nofid;
-    }
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        retval = -ENOENT;
-        goto out_nofid;
-    }
-    retval = v9fs_co_statfs(pdu, &fidp->path, &stbuf);
-    if (retval < 0) {
-        goto out;
-    }
-    retval = v9fs_fill_statfs(s, pdu, &stbuf);
-    if (retval < 0) {
-        goto out;
-    }
-    retval += offset;
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, retval);
-}
-
-static void v9fs_mknod(void *opaque)
-{
-
-    int mode;
-    gid_t gid;
-    int32_t fid;
-    V9fsQID qid;
-    int err = 0;
-    int major, minor;
-    size_t offset = 7;
-    V9fsString name;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dsdddd", &fid, &name, &mode,
-                        &major, &minor, &gid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_mknod(pdu->tag, pdu->id, fid, mode, major, minor);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_mknod(pdu, fidp, &name, fidp->uid, gid,
-                        makedev(major, minor), mode, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    stat_to_qid(&stbuf, &qid);
-    err = pdu_marshal(pdu, offset, "Q", &qid);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_mknod_return(pdu->tag, pdu->id,
-                            qid.type, qid.version, qid.path);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-/*
- * Implement posix byte range locking code
- * Server side handling of locking code is very simple, because 9p server in
- * QEMU can handle only one client. And most of the lock handling
- * (like conflict, merging) etc is done by the VFS layer itself, so no need to
- * do any thing in * qemu 9p server side lock code path.
- * So when a TLOCK request comes, always return success
- */
-static void v9fs_lock(void *opaque)
-{
-    int8_t status;
-    V9fsFlock flock;
-    size_t offset = 7;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    int32_t fid, err = 0;
-    V9fsPDU *pdu = opaque;
-
-    status = P9_LOCK_ERROR;
-    v9fs_string_init(&flock.client_id);
-    err = pdu_unmarshal(pdu, offset, "dbdqqds", &fid, &flock.type,
-                        &flock.flags, &flock.start, &flock.length,
-                        &flock.proc_id, &flock.client_id);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_lock(pdu->tag, pdu->id, fid,
-                    flock.type, flock.start, flock.length);
-
-
-    /* We support only block flag now (that too ignored currently) */
-    if (flock.flags & ~P9_LOCK_FLAGS_BLOCK) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_fstat(pdu, fidp, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    status = P9_LOCK_SUCCESS;
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    err = pdu_marshal(pdu, offset, "b", status);
-    if (err > 0) {
-        err += offset;
-    }
-    trace_v9fs_lock_return(pdu->tag, pdu->id, status);
-    pdu_complete(pdu, err);
-    v9fs_string_free(&flock.client_id);
-}
-
-/*
- * When a TGETLOCK request comes, always return success because all lock
- * handling is done by client's VFS layer.
- */
-static void v9fs_getlock(void *opaque)
-{
-    size_t offset = 7;
-    struct stat stbuf;
-    V9fsFidState *fidp;
-    V9fsGetlock glock;
-    int32_t fid, err = 0;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_string_init(&glock.client_id);
-    err = pdu_unmarshal(pdu, offset, "dbqqds", &fid, &glock.type,
-                        &glock.start, &glock.length, &glock.proc_id,
-                        &glock.client_id);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_getlock(pdu->tag, pdu->id, fid,
-                       glock.type, glock.start, glock.length);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_fstat(pdu, fidp, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    glock.type = P9_LOCK_TYPE_UNLCK;
-    err = pdu_marshal(pdu, offset, "bqqds", glock.type,
-                          glock.start, glock.length, glock.proc_id,
-                          &glock.client_id);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_getlock_return(pdu->tag, pdu->id, glock.type, glock.start,
-                              glock.length, glock.proc_id);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&glock.client_id);
-}
-
-static void v9fs_mkdir(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    size_t offset = 7;
-    int32_t fid;
-    struct stat stbuf;
-    V9fsQID qid;
-    V9fsString name;
-    V9fsFidState *fidp;
-    gid_t gid;
-    int mode;
-    int err = 0;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dsdd", &fid, &name, &mode, &gid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_mkdir(pdu->tag, pdu->id, fid, name.data, mode, gid);
-
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    err = v9fs_co_mkdir(pdu, fidp, &name, mode, fidp->uid, gid, &stbuf);
-    if (err < 0) {
-        goto out;
-    }
-    stat_to_qid(&stbuf, &qid);
-    err = pdu_marshal(pdu, offset, "Q", &qid);
-    if (err < 0) {
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_mkdir_return(pdu->tag, pdu->id,
-                            qid.type, qid.version, qid.path, err);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-static void v9fs_xattrwalk(void *opaque)
-{
-    int64_t size;
-    V9fsString name;
-    ssize_t err = 0;
-    size_t offset = 7;
-    int32_t fid, newfid;
-    V9fsFidState *file_fidp;
-    V9fsFidState *xattr_fidp = NULL;
-    V9fsPDU *pdu = opaque;
-    V9fsState *s = pdu->s;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dds", &fid, &newfid, &name);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_xattrwalk(pdu->tag, pdu->id, fid, newfid, name.data);
-
-    file_fidp = get_fid(pdu, fid);
-    if (file_fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-    xattr_fidp = alloc_fid(s, newfid);
-    if (xattr_fidp == NULL) {
-        err = -EINVAL;
-        goto out;
-    }
-    v9fs_path_copy(&xattr_fidp->path, &file_fidp->path);
-    if (name.data == NULL) {
-        /*
-         * listxattr request. Get the size first
-         */
-        size = v9fs_co_llistxattr(pdu, &xattr_fidp->path, NULL, 0);
-        if (size < 0) {
-            err = size;
-            clunk_fid(s, xattr_fidp->fid);
-            goto out;
-        }
-        /*
-         * Read the xattr value
-         */
-        xattr_fidp->fs.xattr.len = size;
-        xattr_fidp->fid_type = P9_FID_XATTR;
-        xattr_fidp->fs.xattr.copied_len = -1;
-        if (size) {
-            xattr_fidp->fs.xattr.value = g_malloc(size);
-            err = v9fs_co_llistxattr(pdu, &xattr_fidp->path,
-                                     xattr_fidp->fs.xattr.value,
-                                     xattr_fidp->fs.xattr.len);
-            if (err < 0) {
-                clunk_fid(s, xattr_fidp->fid);
-                goto out;
-            }
-        }
-        err = pdu_marshal(pdu, offset, "q", size);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset;
-    } else {
-        /*
-         * specific xattr fid. We check for xattr
-         * presence also collect the xattr size
-         */
-        size = v9fs_co_lgetxattr(pdu, &xattr_fidp->path,
-                                 &name, NULL, 0);
-        if (size < 0) {
-            err = size;
-            clunk_fid(s, xattr_fidp->fid);
-            goto out;
-        }
-        /*
-         * Read the xattr value
-         */
-        xattr_fidp->fs.xattr.len = size;
-        xattr_fidp->fid_type = P9_FID_XATTR;
-        xattr_fidp->fs.xattr.copied_len = -1;
-        if (size) {
-            xattr_fidp->fs.xattr.value = g_malloc(size);
-            err = v9fs_co_lgetxattr(pdu, &xattr_fidp->path,
-                                    &name, xattr_fidp->fs.xattr.value,
-                                    xattr_fidp->fs.xattr.len);
-            if (err < 0) {
-                clunk_fid(s, xattr_fidp->fid);
-                goto out;
-            }
-        }
-        err = pdu_marshal(pdu, offset, "q", size);
-        if (err < 0) {
-            goto out;
-        }
-        err += offset;
-    }
-    trace_v9fs_xattrwalk_return(pdu->tag, pdu->id, size);
-out:
-    put_fid(pdu, file_fidp);
-    if (xattr_fidp) {
-        put_fid(pdu, xattr_fidp);
-    }
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-static void v9fs_xattrcreate(void *opaque)
-{
-    int flags;
-    int32_t fid;
-    int64_t size;
-    ssize_t err = 0;
-    V9fsString name;
-    size_t offset = 7;
-    V9fsFidState *file_fidp;
-    V9fsFidState *xattr_fidp;
-    V9fsPDU *pdu = opaque;
-
-    v9fs_string_init(&name);
-    err = pdu_unmarshal(pdu, offset, "dsqd", &fid, &name, &size, &flags);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_xattrcreate(pdu->tag, pdu->id, fid, name.data, size, flags);
-
-    file_fidp = get_fid(pdu, fid);
-    if (file_fidp == NULL) {
-        err = -EINVAL;
-        goto out_nofid;
-    }
-    /* Make the file fid point to xattr */
-    xattr_fidp = file_fidp;
-    xattr_fidp->fid_type = P9_FID_XATTR;
-    xattr_fidp->fs.xattr.copied_len = 0;
-    xattr_fidp->fs.xattr.len = size;
-    xattr_fidp->fs.xattr.flags = flags;
-    v9fs_string_init(&xattr_fidp->fs.xattr.name);
-    v9fs_string_copy(&xattr_fidp->fs.xattr.name, &name);
-    xattr_fidp->fs.xattr.value = g_malloc(size);
-    err = offset;
-    put_fid(pdu, file_fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-    v9fs_string_free(&name);
-}
-
-static void v9fs_readlink(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    size_t offset = 7;
-    V9fsString target;
-    int32_t fid;
-    int err = 0;
-    V9fsFidState *fidp;
-
-    err = pdu_unmarshal(pdu, offset, "d", &fid);
-    if (err < 0) {
-        goto out_nofid;
-    }
-    trace_v9fs_readlink(pdu->tag, pdu->id, fid);
-    fidp = get_fid(pdu, fid);
-    if (fidp == NULL) {
-        err = -ENOENT;
-        goto out_nofid;
-    }
-
-    v9fs_string_init(&target);
-    err = v9fs_co_readlink(pdu, &fidp->path, &target);
-    if (err < 0) {
-        goto out;
-    }
-    err = pdu_marshal(pdu, offset, "s", &target);
-    if (err < 0) {
-        v9fs_string_free(&target);
-        goto out;
-    }
-    err += offset;
-    trace_v9fs_readlink_return(pdu->tag, pdu->id, target.data);
-    v9fs_string_free(&target);
-out:
-    put_fid(pdu, fidp);
-out_nofid:
-    pdu_complete(pdu, err);
-}
-
-static CoroutineEntry *pdu_co_handlers[] = {
-    [P9_TREADDIR] = v9fs_readdir,
-    [P9_TSTATFS] = v9fs_statfs,
-    [P9_TGETATTR] = v9fs_getattr,
-    [P9_TSETATTR] = v9fs_setattr,
-    [P9_TXATTRWALK] = v9fs_xattrwalk,
-    [P9_TXATTRCREATE] = v9fs_xattrcreate,
-    [P9_TMKNOD] = v9fs_mknod,
-    [P9_TRENAME] = v9fs_rename,
-    [P9_TLOCK] = v9fs_lock,
-    [P9_TGETLOCK] = v9fs_getlock,
-    [P9_TRENAMEAT] = v9fs_renameat,
-    [P9_TREADLINK] = v9fs_readlink,
-    [P9_TUNLINKAT] = v9fs_unlinkat,
-    [P9_TMKDIR] = v9fs_mkdir,
-    [P9_TVERSION] = v9fs_version,
-    [P9_TLOPEN] = v9fs_open,
-    [P9_TATTACH] = v9fs_attach,
-    [P9_TSTAT] = v9fs_stat,
-    [P9_TWALK] = v9fs_walk,
-    [P9_TCLUNK] = v9fs_clunk,
-    [P9_TFSYNC] = v9fs_fsync,
-    [P9_TOPEN] = v9fs_open,
-    [P9_TREAD] = v9fs_read,
-#if 0
-    [P9_TAUTH] = v9fs_auth,
-#endif
-    [P9_TFLUSH] = v9fs_flush,
-    [P9_TLINK] = v9fs_link,
-    [P9_TSYMLINK] = v9fs_symlink,
-    [P9_TCREATE] = v9fs_create,
-    [P9_TLCREATE] = v9fs_lcreate,
-    [P9_TWRITE] = v9fs_write,
-    [P9_TWSTAT] = v9fs_wstat,
-    [P9_TREMOVE] = v9fs_remove,
-};
-
-static void v9fs_op_not_supp(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    pdu_complete(pdu, -EOPNOTSUPP);
-}
-
-static void v9fs_fs_ro(void *opaque)
-{
-    V9fsPDU *pdu = opaque;
-    pdu_complete(pdu, -EROFS);
-}
-
-static inline bool is_read_only_op(V9fsPDU *pdu)
-{
-    switch (pdu->id) {
-    case P9_TREADDIR:
-    case P9_TSTATFS:
-    case P9_TGETATTR:
-    case P9_TXATTRWALK:
-    case P9_TLOCK:
-    case P9_TGETLOCK:
-    case P9_TREADLINK:
-    case P9_TVERSION:
-    case P9_TLOPEN:
-    case P9_TATTACH:
-    case P9_TSTAT:
-    case P9_TWALK:
-    case P9_TCLUNK:
-    case P9_TFSYNC:
-    case P9_TOPEN:
-    case P9_TREAD:
-    case P9_TAUTH:
-    case P9_TFLUSH:
-        return 1;
-    default:
-        return 0;
-    }
-}
-
-void pdu_submit(V9fsPDU *pdu)
-{
-    Coroutine *co;
-    CoroutineEntry *handler;
-    V9fsState *s = pdu->s;
-
-    if (pdu->id >= ARRAY_SIZE(pdu_co_handlers) ||
-        (pdu_co_handlers[pdu->id] == NULL)) {
-        handler = v9fs_op_not_supp;
-    } else {
-        handler = pdu_co_handlers[pdu->id];
-    }
-
-    if (is_ro_export(&s->ctx) && !is_read_only_op(pdu)) {
-        handler = v9fs_fs_ro;
-    }
-    co = qemu_coroutine_create(handler);
-    qemu_coroutine_enter(co, pdu);
-}
-
-static void __attribute__((__constructor__)) v9fs_set_fd_limit(void)
-{
-    struct rlimit rlim;
-    if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
-        fprintf(stderr, "Failed to get the resource limit\n");
-        exit(1);
-    }
-    open_fd_hw = rlim.rlim_cur - MIN(400, rlim.rlim_cur/3);
-    open_fd_rc = rlim.rlim_cur/2;
-}
