Adding upstream version 1:7.2+dfsg.upstream/1%7.2+dfsgupstream

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

1 files changed, 4363 insertions, 0 deletions

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
new file mode 100644
index 00000000..072cf679
--- /dev/null
+++ b/hw/9pfs/9p.c
@@ -0,0 +1,4363 @@
+/*
+ * 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.
+ *
+ */
+
+/*
+ * Not so fast! You might want to read the 9p developer docs first:
+ * https://wiki.qemu.org/Documentation/9p
+ */
+
+#include "qemu/osdep.h"
+#ifdef CONFIG_LINUX
+#include <linux/limits.h>
+#else
+#include <limits.h>
+#endif
+#include <glib/gprintf.h>
+#include "hw/virtio/virtio.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/iov.h"
+#include "qemu/main-loop.h"
+#include "qemu/sockets.h"
+#include "virtio-9p.h"
+#include "fsdev/qemu-fsdev.h"
+#include "9p-xattr.h"
+#include "9p-util.h"
+#include "coth.h"
+#include "trace.h"
+#include "migration/blocker.h"
+#include "qemu/xxhash.h"
+#include <math.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,
+};
+
+P9ARRAY_DEFINE_TYPE(V9fsPath, v9fs_path_free);
+
+static ssize_t pdu_marshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
+{
+    ssize_t ret;
+    va_list ap;
+
+    va_start(ap, fmt);
+    ret = pdu->s->transport->pdu_vmarshal(pdu, offset, fmt, ap);
+    va_end(ap);
+
+    return ret;
+}
+
+static ssize_t pdu_unmarshal(V9fsPDU *pdu, size_t offset, const char *fmt, ...)
+{
+    ssize_t ret;
+    va_list ap;
+
+    va_start(ap, fmt);
+    ret = pdu->s->transport->pdu_vunmarshal(pdu, offset, fmt, ap);
+    va_end(ap);
+
+    return ret;
+}
+
+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;
+}
+
+typedef struct DotlOpenflagMap {
+    int dotl_flag;
+    int open_flag;
+} DotlOpenflagMap;
+
+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;
+
+    DotlOpenflagMap 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 },
+#ifndef CONFIG_DARWIN
+        { P9_DOTL_NOATIME, O_NOATIME },
+        /*
+         *  On Darwin, we could map to F_NOCACHE, which is
+         *  similar, but doesn't quite have the same
+         *  semantics. However, we don't support O_DIRECT
+         *  even on linux at the moment, so we just ignore
+         *  it here.
+         */
+        { P9_DOTL_DIRECT, O_DIRECT },
+#endif
+        { P9_DOTL_LARGEFILE, O_LARGEFILE },
+        { P9_DOTL_DIRECTORY, O_DIRECTORY },
+        { P9_DOTL_NOFOLLOW, O_NOFOLLOW },
+        { 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);
+#ifndef CONFIG_DARWIN
+    /*
+     * Ignore direct disk access hint until the server supports it.
+     */
+    flags &= ~O_DIRECT;
+#endif
+    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 G_GNUC_PRINTF(2, 3)
+v9fs_path_sprintf(V9fsPath *path, const char *fmt, ...)
+{
+    va_list ap;
+
+    v9fs_path_free(path);
+
+    va_start(ap, fmt);
+    /* Bump the size for including terminating NULL */
+    path->size = g_vasprintf(&path->data, fmt, ap) + 1;
+    va_end(ap);
+}
+
+void v9fs_path_copy(V9fsPath *dst, const V9fsPath *src)
+{
+    v9fs_path_free(dst);
+    dst->size = src->size;
+    dst->data = g_memdup(src->data, src->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 coroutine_fn 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.stream == NULL) {
+            do {
+                err = v9fs_co_opendir(pdu, f);
+            } while (err == -EINTR && !pdu->cancelled);
+        }
+    }
+    return err;
+}
+
+static V9fsFidState *coroutine_fn get_fid(V9fsPDU *pdu, int32_t fid)
+{
+    int err;
+    V9fsFidState *f;
+    V9fsState *s = pdu->s;
+
+    f = g_hash_table_lookup(s->fids, GINT_TO_POINTER(fid));
+    if (f) {
+        BUG_ON(f->clunked);
+        /*
+         * 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;
+
+    f = g_hash_table_lookup(s->fids, GINT_TO_POINTER(fid));
+    if (f) {
+        /* If fid is already there return NULL */
+        BUG_ON(f->clunked);
+        return NULL;
+    }
+    f = g_new0(V9fsFidState, 1);
+    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;
+    g_hash_table_insert(s->fids, GINT_TO_POINTER(fid), f);
+
+    v9fs_readdir_init(s->proto_version, &f->fs.dir);
+    v9fs_readdir_init(s->proto_version, &f->fs_reclaim.dir);
+
+    return f;
+}
+
+static int coroutine_fn v9fs_xattr_fid_clunk(V9fsPDU *pdu, V9fsFidState *fidp)
+{
+    int retval = 0;
+
+    if (fidp->fs.xattr.xattrwalk_fid) {
+        /* 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:
+    g_free(fidp->fs.xattr.value);
+    return retval;
+}
+
+static int coroutine_fn 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.stream != 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 coroutine_fn 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 *fidp;
+
+    /* TODO: Use g_hash_table_steal_extended() instead? */
+    fidp = g_hash_table_lookup(s->fids, GINT_TO_POINTER(fid));
+    if (fidp) {
+        g_hash_table_remove(s->fids, GINT_TO_POINTER(fid));
+        fidp->clunked = true;
+        return fidp;
+    }
+    return NULL;
+}
+
+void coroutine_fn v9fs_reclaim_fd(V9fsPDU *pdu)
+{
+    int reclaim_count = 0;
+    V9fsState *s = pdu->s;
+    V9fsFidState *f;
+    GHashTableIter iter;
+    gpointer fid;
+
+    g_hash_table_iter_init(&iter, s->fids);
+
+    QSLIST_HEAD(, V9fsFidState) reclaim_list =
+        QSLIST_HEAD_INITIALIZER(reclaim_list);
+
+    while (g_hash_table_iter_next(&iter, &fid, (gpointer *) &f)) {
+        /*
+         * 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++;
+                QSLIST_INSERT_HEAD(&reclaim_list, f, reclaim_next);
+                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.stream != NULL) {
+                /*
+                 * Up the reference count so that
+                 * a clunk request won't free this fid
+                 */
+                f->ref++;
+                QSLIST_INSERT_HEAD(&reclaim_list, f, reclaim_next);
+                f->fs_reclaim.dir.stream = f->fs.dir.stream;
+                f->fs.dir.stream = 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 (!QSLIST_EMPTY(&reclaim_list)) {
+        f = QSLIST_FIRST(&reclaim_list);
+        QSLIST_REMOVE(&reclaim_list, f, V9fsFidState, reclaim_next);
+        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);
+        }
+        /*
+         * Now drop the fid reference, free it
+         * if clunked.
+         */
+        put_fid(pdu, f);
+    }
+}
+
+/*
+ * This is used when a path is removed from the directory tree. Any
+ * fids that still reference it must not be closed from then on, since
+ * they cannot be reopened.
+ */
+static int coroutine_fn v9fs_mark_fids_unreclaim(V9fsPDU *pdu, V9fsPath *path)
+{
+    int err = 0;
+    V9fsState *s = pdu->s;
+    V9fsFidState *fidp;
+    gpointer fid;
+    GHashTableIter iter;
+    /*
+     * The most common case is probably that we have exactly one
+     * fid for the given path, so preallocate exactly one.
+     */
+    g_autoptr(GArray) to_reopen = g_array_sized_new(FALSE, FALSE,
+            sizeof(V9fsFidState *), 1);
+    gint i;
+
+    g_hash_table_iter_init(&iter, s->fids);
+
+    /*
+     * We iterate over the fid table looking for the entries we need
+     * to reopen, and store them in to_reopen. This is because
+     * v9fs_reopen_fid() and put_fid() yield. This allows the fid table
+     * to be modified in the meantime, invalidating our iterator.
+     */
+    while (g_hash_table_iter_next(&iter, &fid, (gpointer *) &fidp)) {
+        if (fidp->path.size == path->size &&
+            !memcmp(fidp->path.data, path->data, path->size)) {
+            /*
+             * Ensure the fid survives a potential clunk request during
+             * v9fs_reopen_fid or put_fid.
+             */
+            fidp->ref++;
+            fidp->flags |= FID_NON_RECLAIMABLE;
+            g_array_append_val(to_reopen, fidp);
+        }
+    }
+
+    for (i = 0; i < to_reopen->len; i++) {
+        fidp = g_array_index(to_reopen, V9fsFidState*, i);
+        /* reopen the file/dir if already closed */
+        err = v9fs_reopen_fid(pdu, fidp);
+        if (err < 0) {
+            break;
+        }
+    }
+
+    for (i = 0; i < to_reopen->len; i++) {
+        put_fid(pdu, g_array_index(to_reopen, V9fsFidState*, i));
+    }
+    return err;
+}
+
+static void coroutine_fn virtfs_reset(V9fsPDU *pdu)
+{
+    V9fsState *s = pdu->s;
+    V9fsFidState *fidp;
+    GList *freeing;
+    /*
+     * Get a list of all the values (fid states) in the table, which
+     * we then...
+     */
+    g_autoptr(GList) fids = g_hash_table_get_values(s->fids);
+
+    /* ... remove from the table, taking over ownership. */
+    g_hash_table_steal_all(s->fids);
+
+    /*
+     * This allows us to release our references to them asynchronously without
+     * iterating over the hash table and risking iterator invalidation
+     * through concurrent modifications.
+     */
+    for (freeing = fids; freeing; freeing = freeing->next) {
+        fidp = freeing->data;
+        fidp->ref++;
+        fidp->clunked = true;
+        put_fid(pdu, fidp);
+    }
+}
+
+#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)
+
+/* Mirrors all bits of a byte. So e.g. binary 10100000 would become 00000101. */
+static inline uint8_t mirror8bit(uint8_t byte)
+{
+    return (byte * 0x0202020202ULL & 0x010884422010ULL) % 1023;
+}
+
+/* Same as mirror8bit() just for a 64 bit data type instead for a byte. */
+static inline uint64_t mirror64bit(uint64_t value)
+{
+    return ((uint64_t)mirror8bit(value         & 0xff) << 56) |
+           ((uint64_t)mirror8bit((value >> 8)  & 0xff) << 48) |
+           ((uint64_t)mirror8bit((value >> 16) & 0xff) << 40) |
+           ((uint64_t)mirror8bit((value >> 24) & 0xff) << 32) |
+           ((uint64_t)mirror8bit((value >> 32) & 0xff) << 24) |
+           ((uint64_t)mirror8bit((value >> 40) & 0xff) << 16) |
+           ((uint64_t)mirror8bit((value >> 48) & 0xff) << 8)  |
+           ((uint64_t)mirror8bit((value >> 56) & 0xff));
+}
+
+/*
+ * Parameter k for the Exponential Golomb algorihm to be used.
+ *
+ * The smaller this value, the smaller the minimum bit count for the Exp.
+ * Golomb generated affixes will be (at lowest index) however for the
+ * price of having higher maximum bit count of generated affixes (at highest
+ * index). Likewise increasing this parameter yields in smaller maximum bit
+ * count for the price of having higher minimum bit count.
+ *
+ * In practice that means: a good value for k depends on the expected amount
+ * of devices to be exposed by one export. For a small amount of devices k
+ * should be small, for a large amount of devices k might be increased
+ * instead. The default of k=0 should be fine for most users though.
+ *
+ * IMPORTANT: In case this ever becomes a runtime parameter; the value of
+ * k should not change as long as guest is still running! Because that would
+ * cause completely different inode numbers to be generated on guest.
+ */
+#define EXP_GOLOMB_K    0
+
+/**
+ * expGolombEncode() - Exponential Golomb algorithm for arbitrary k
+ *                     (including k=0).
+ *
+ * @n: natural number (or index) of the prefix to be generated
+ *     (1, 2, 3, ...)
+ * @k: parameter k of Exp. Golomb algorithm to be used
+ *     (see comment on EXP_GOLOMB_K macro for details about k)
+ * Return: prefix for given @n and @k
+ *
+ * The Exponential Golomb algorithm generates prefixes (NOT suffixes!)
+ * with growing length and with the mathematical property of being
+ * "prefix-free". The latter means the generated prefixes can be prepended
+ * in front of arbitrary numbers and the resulting concatenated numbers are
+ * guaranteed to be always unique.
+ *
+ * This is a minor adjustment to the original Exp. Golomb algorithm in the
+ * sense that lowest allowed index (@n) starts with 1, not with zero.
+ */
+static VariLenAffix expGolombEncode(uint64_t n, int k)
+{
+    const uint64_t value = n + (1 << k) - 1;
+    const int bits = (int) log2(value) + 1;
+    return (VariLenAffix) {
+        .type = AffixType_Prefix,
+        .value = value,
+        .bits = bits + MAX((bits - 1 - k), 0)
+    };
+}
+
+/**
+ * invertAffix() - Converts a suffix into a prefix, or a prefix into a suffix.
+ * @affix: either suffix or prefix to be inverted
+ * Return: inversion of passed @affix
+ *
+ * Simply mirror all bits of the affix value, for the purpose to preserve
+ * respectively the mathematical "prefix-free" or "suffix-free" property
+ * after the conversion.
+ *
+ * If a passed prefix is suitable to create unique numbers, then the
+ * returned suffix is suitable to create unique numbers as well (and vice
+ * versa).
+ */
+static VariLenAffix invertAffix(const VariLenAffix *affix)
+{
+    return (VariLenAffix) {
+        .type =
+            (affix->type == AffixType_Suffix) ?
+                AffixType_Prefix : AffixType_Suffix,
+        .value =
+            mirror64bit(affix->value) >>
+            ((sizeof(affix->value) * 8) - affix->bits),
+        .bits = affix->bits
+    };
+}
+
+/**
+ * affixForIndex() - Generates suffix numbers with "suffix-free" property.
+ * @index: natural number (or index) of the suffix to be generated
+ *         (1, 2, 3, ...)
+ * Return: Suffix suitable to assemble unique number.
+ *
+ * This is just a wrapper function on top of the Exp. Golomb algorithm.
+ *
+ * Since the Exp. Golomb algorithm generates prefixes, but we need suffixes,
+ * this function converts the Exp. Golomb prefixes into appropriate suffixes
+ * which are still suitable for generating unique numbers.
+ */
+static VariLenAffix affixForIndex(uint64_t index)
+{
+    VariLenAffix prefix;
+    prefix = expGolombEncode(index, EXP_GOLOMB_K);
+    return invertAffix(&prefix); /* convert prefix to suffix */
+}
+
+/* creative abuse of tb_hash_func7, which is based on xxhash */
+static uint32_t qpp_hash(QppEntry e)
+{
+    return qemu_xxhash7(e.ino_prefix, e.dev, 0, 0, 0);
+}
+
+static uint32_t qpf_hash(QpfEntry e)
+{
+    return qemu_xxhash7(e.ino, e.dev, 0, 0, 0);
+}
+
+static bool qpd_cmp_func(const void *obj, const void *userp)
+{
+    const QpdEntry *e1 = obj, *e2 = userp;
+    return e1->dev == e2->dev;
+}
+
+static bool qpp_cmp_func(const void *obj, const void *userp)
+{
+    const QppEntry *e1 = obj, *e2 = userp;
+    return e1->dev == e2->dev && e1->ino_prefix == e2->ino_prefix;
+}
+
+static bool qpf_cmp_func(const void *obj, const void *userp)
+{
+    const QpfEntry *e1 = obj, *e2 = userp;
+    return e1->dev == e2->dev && e1->ino == e2->ino;
+}
+
+static void qp_table_remove(void *p, uint32_t h, void *up)
+{
+    g_free(p);
+}
+
+static void qp_table_destroy(struct qht *ht)
+{
+    if (!ht || !ht->map) {
+        return;
+    }
+    qht_iter(ht, qp_table_remove, NULL);
+    qht_destroy(ht);
+}
+
+static void qpd_table_init(struct qht *ht)
+{
+    qht_init(ht, qpd_cmp_func, 1, QHT_MODE_AUTO_RESIZE);
+}
+
+static void qpp_table_init(struct qht *ht)
+{
+    qht_init(ht, qpp_cmp_func, 1, QHT_MODE_AUTO_RESIZE);
+}
+
+static void qpf_table_init(struct qht *ht)
+{
+    qht_init(ht, qpf_cmp_func, 1 << 16, QHT_MODE_AUTO_RESIZE);
+}
+
+/*
+ * Returns how many (high end) bits of inode numbers of the passed fs
+ * device shall be used (in combination with the device number) to
+ * generate hash values for qpp_table entries.
+ *
+ * This function is required if variable length suffixes are used for inode
+ * number mapping on guest level. Since a device may end up having multiple
+ * entries in qpp_table, each entry most probably with a different suffix
+ * length, we thus need this function in conjunction with qpd_table to
+ * "agree" about a fix amount of bits (per device) to be always used for
+ * generating hash values for the purpose of accessing qpp_table in order
+ * get consistent behaviour when accessing qpp_table.
+ */
+static int qid_inode_prefix_hash_bits(V9fsPDU *pdu, dev_t dev)
+{
+    QpdEntry lookup = {
+        .dev = dev
+    }, *val;
+    uint32_t hash = dev;
+    VariLenAffix affix;
+
+    val = qht_lookup(&pdu->s->qpd_table, &lookup, hash);
+    if (!val) {
+        val = g_new0(QpdEntry, 1);
+        *val = lookup;
+        affix = affixForIndex(pdu->s->qp_affix_next);
+        val->prefix_bits = affix.bits;
+        qht_insert(&pdu->s->qpd_table, val, hash, NULL);
+        pdu->s->qp_ndevices++;
+    }
+    return val->prefix_bits;
+}
+
+/*
+ * Slow / full mapping host inode nr -> guest inode nr.
+ *
+ * This function performs a slower and much more costly remapping of an
+ * original file inode number on host to an appropriate different inode
+ * number on guest. For every (dev, inode) combination on host a new
+ * sequential number is generated, cached and exposed as inode number on
+ * guest.
+ *
+ * This is just a "last resort" fallback solution if the much faster/cheaper
+ * qid_path_suffixmap() failed. In practice this slow / full mapping is not
+ * expected ever to be used at all though.
+ *
+ * See qid_path_suffixmap() for details
+ *
+ */
+static int qid_path_fullmap(V9fsPDU *pdu, const struct stat *stbuf,
+                            uint64_t *path)
+{
+    QpfEntry lookup = {
+        .dev = stbuf->st_dev,
+        .ino = stbuf->st_ino
+    }, *val;
+    uint32_t hash = qpf_hash(lookup);
+    VariLenAffix affix;
+
+    val = qht_lookup(&pdu->s->qpf_table, &lookup, hash);
+
+    if (!val) {
+        if (pdu->s->qp_fullpath_next == 0) {
+            /* no more files can be mapped :'( */
+            error_report_once(
+                "9p: No more prefixes available for remapping inodes from "
+                "host to guest."
+            );
+            return -ENFILE;
+        }
+
+        val = g_new0(QpfEntry, 1);
+        *val = lookup;
+
+        /* new unique inode and device combo */
+        affix = affixForIndex(
+            1ULL << (sizeof(pdu->s->qp_affix_next) * 8)
+        );
+        val->path = (pdu->s->qp_fullpath_next++ << affix.bits) | affix.value;
+        pdu->s->qp_fullpath_next &= ((1ULL << (64 - affix.bits)) - 1);
+        qht_insert(&pdu->s->qpf_table, val, hash, NULL);
+    }
+
+    *path = val->path;
+    return 0;
+}
+
+/*
+ * Quick mapping host inode nr -> guest inode nr.
+ *
+ * This function performs quick remapping of an original file inode number
+ * on host to an appropriate different inode number on guest. This remapping
+ * of inodes is required to avoid inode nr collisions on guest which would
+ * happen if the 9p export contains more than 1 exported file system (or
+ * more than 1 file system data set), because unlike on host level where the
+ * files would have different device nrs, all files exported by 9p would
+ * share the same device nr on guest (the device nr of the virtual 9p device
+ * that is).
+ *
+ * Inode remapping is performed by chopping off high end bits of the original
+ * inode number from host, shifting the result upwards and then assigning a
+ * generated suffix number for the low end bits, where the same suffix number
+ * will be shared by all inodes with the same device id AND the same high end
+ * bits that have been chopped off. That approach utilizes the fact that inode
+ * numbers very likely share the same high end bits (i.e. due to their common
+ * sequential generation by file systems) and hence we only have to generate
+ * and track a very limited amount of suffixes in practice due to that.
+ *
+ * We generate variable size suffixes for that purpose. The 1st generated
+ * suffix will only have 1 bit and hence we only need to chop off 1 bit from
+ * the original inode number. The subsequent suffixes being generated will
+ * grow in (bit) size subsequently, i.e. the 2nd and 3rd suffix being
+ * generated will have 3 bits and hence we have to chop off 3 bits from their
+ * original inodes, and so on. That approach of using variable length suffixes
+ * (i.e. over fixed size ones) utilizes the fact that in practice only a very
+ * limited amount of devices are shared by the same export (e.g. typically
+ * less than 2 dozen devices per 9p export), so in practice we need to chop
+ * off less bits than with fixed size prefixes and yet are flexible to add
+ * new devices at runtime below host's export directory at any time without
+ * having to reboot guest nor requiring to reconfigure guest for that. And due
+ * to the very limited amount of original high end bits that we chop off that
+ * way, the total amount of suffixes we need to generate is less than by using
+ * fixed size prefixes and hence it also improves performance of the inode
+ * remapping algorithm, and finally has the nice side effect that the inode
+ * numbers on guest will be much smaller & human friendly. ;-)
+ */
+static int qid_path_suffixmap(V9fsPDU *pdu, const struct stat *stbuf,
+                              uint64_t *path)
+{
+    const int ino_hash_bits = qid_inode_prefix_hash_bits(pdu, stbuf->st_dev);
+    QppEntry lookup = {
+        .dev = stbuf->st_dev,
+        .ino_prefix = (uint16_t) (stbuf->st_ino >> (64 - ino_hash_bits))
+    }, *val;
+    uint32_t hash = qpp_hash(lookup);
+
+    val = qht_lookup(&pdu->s->qpp_table, &lookup, hash);
+
+    if (!val) {
+        if (pdu->s->qp_affix_next == 0) {
+            /* we ran out of affixes */
+            warn_report_once(
+                "9p: Potential degraded performance of inode remapping"
+            );
+            return -ENFILE;
+        }
+
+        val = g_new0(QppEntry, 1);
+        *val = lookup;
+
+        /* new unique inode affix and device combo */
+        val->qp_affix_index = pdu->s->qp_affix_next++;
+        val->qp_affix = affixForIndex(val->qp_affix_index);
+        qht_insert(&pdu->s->qpp_table, val, hash, NULL);
+    }
+    /* assuming generated affix to be suffix type, not prefix */
+    *path = (stbuf->st_ino << val->qp_affix.bits) | val->qp_affix.value;
+    return 0;
+}
+
+static int stat_to_qid(V9fsPDU *pdu, const struct stat *stbuf, V9fsQID *qidp)
+{
+    int err;
+    size_t size;
+
+    if (pdu->s->ctx.export_flags & V9FS_REMAP_INODES) {
+        /* map inode+device to qid path (fast path) */
+        err = qid_path_suffixmap(pdu, stbuf, &qidp->path);
+        if (err == -ENFILE) {
+            /* fast path didn't work, fall back to full map */
+            err = qid_path_fullmap(pdu, stbuf, &qidp->path);
+        }
+        if (err) {
+            return err;
+        }
+    } else {
+        if (pdu->s->dev_id != stbuf->st_dev) {
+            if (pdu->s->ctx.export_flags & V9FS_FORBID_MULTIDEVS) {
+                error_report_once(
+                    "9p: Multiple devices detected in same VirtFS export. "
+                    "Access of guest to additional devices is (partly) "
+                    "denied due to virtfs option 'multidevs=forbid' being "
+                    "effective."
+                );
+                return -ENODEV;
+            } else {
+                warn_report_once(
+                    "9p: Multiple devices detected in same VirtFS export, "
+                    "which might lead to file ID collisions and severe "
+                    "misbehaviours on guest! You should either use a "
+                    "separate export for each device shared from host or "
+                    "use virtfs option 'multidevs=remap'!"
+                );
+            }
+        }
+        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;
+    }
+
+    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)
+{
+    V9fsState *s = pdu->s;
+
+    g_assert(!pdu->cancelled);
+    QLIST_REMOVE(pdu, next);
+    QLIST_INSERT_HEAD(&s->free_list, pdu, next);
+}
+
+static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len)
+{
+    int8_t id = pdu->id + 1; /* Response */
+    V9fsState *s = pdu->s;
+    int ret;
+
+    /*
+     * The 9p spec requires that successfully cancelled pdus receive no reply.
+     * Sending a reply would confuse clients because they would
+     * assume that any EINTR is the actual result of the operation,
+     * rather than a consequence of the cancellation. However, if
+     * the operation completed (succesfully or with an error other
+     * than caused be cancellation), we do send out that reply, both
+     * for efficiency and to avoid confusing the rest of the state machine
+     * that assumes passing a non-error here will mean a successful
+     * transmission of the reply.
+     */
+    bool discard = pdu->cancelled && len == -EINTR;
+    if (discard) {
+        trace_v9fs_rcancel(pdu->tag, pdu->id);
+        pdu->size = 0;
+        goto out_notify;
+    }
+
+    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);
+
+            ret = pdu_marshal(pdu, len, "s", &str);
+            if (ret < 0) {
+                goto out_notify;
+            }
+            len += ret;
+            id = P9_RERROR;
+        } else {
+            err = errno_to_dotl(err);
+        }
+
+        ret = pdu_marshal(pdu, len, "d", err);
+        if (ret < 0) {
+            goto out_notify;
+        }
+        len += ret;
+
+        if (s->proto_version == V9FS_PROTO_2000L) {
+            id = P9_RLERROR;
+        }
+        trace_v9fs_rerror(pdu->tag, pdu->id, err); /* Trace ERROR */
+    }
+
+    /* fill out the header */
+    if (pdu_marshal(pdu, 0, "dbw", (int32_t)len, id, pdu->tag) < 0) {
+        goto out_notify;
+    }
+
+    /* keep these in sync */
+    pdu->size = len;
+    pdu->id = id;
+
+out_notify:
+    pdu->s->transport->push_and_notify(pdu);
+
+    /* Now wakeup anybody waiting in flush for this request */
+    if (!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 == 0xff &&
+        stat->qid.version == (uint32_t) -1 &&
+        stat->qid.path == (uint64_t) -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 coroutine_fn stat_to_v9stat(V9fsPDU *pdu, V9fsPath *path,
+                                       const char *basename,
+                                       const struct stat *stbuf,
+                                       V9fsStat *v9stat)
+{
+    int err;
+
+    memset(v9stat, 0, sizeof(*v9stat));
+
+    err = stat_to_qid(pdu, stbuf, &v9stat->qid);
+    if (err < 0) {
+        return err;
+    }
+    v9stat->mode = stat_to_v9mode(stbuf);
+    v9stat->atime = stbuf->st_atime;
+    v9stat->mtime = stbuf->st_mtime;
+    v9stat->length = stbuf->st_size;
+
+    v9fs_string_free(&v9stat->uid);
+    v9fs_string_free(&v9stat->gid);
+    v9fs_string_free(&v9stat->muid);
+
+    v9stat->n_uid = stbuf->st_uid;
+    v9stat->n_gid = stbuf->st_gid;
+    v9stat->n_muid = 0;
+
+    v9fs_string_free(&v9stat->extension);
+
+    if (v9stat->mode & P9_STAT_MODE_SYMLINK) {
+        err = v9fs_co_readlink(pdu, path, &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);
+    }
+
+    v9fs_string_sprintf(&v9stat->name, "%s", basename);
+
+    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 */
+
+
+/**
+ * blksize_to_iounit() - Block size exposed to 9p client.
+ * Return: block size
+ *
+ * @pdu: 9p client request
+ * @blksize: host filesystem's block size
+ *
+ * Convert host filesystem's block size into an appropriate block size for
+ * 9p client (guest OS side). The value returned suggests an "optimum" block
+ * size for 9p I/O, i.e. to maximize performance.
+ */
+static int32_t blksize_to_iounit(const V9fsPDU *pdu, int32_t blksize)
+{
+    int32_t iounit = 0;
+    V9fsState *s = pdu->s;
+
+    /*
+     * iounit should be multiples of blksize (host filesystem block size)
+     * as well as less than (client msize - P9_IOHDRSZ)
+     */
+    if (blksize) {
+        iounit = QEMU_ALIGN_DOWN(s->msize - P9_IOHDRSZ, blksize);
+    }
+    if (!iounit) {
+        iounit = s->msize - P9_IOHDRSZ;
+    }
+    return iounit;
+}
+
+static int32_t stat_to_iounit(const V9fsPDU *pdu, const struct stat *stbuf)
+{
+    return blksize_to_iounit(pdu, stbuf->st_blksize);
+}
+
+static int stat_to_v9stat_dotl(V9fsPDU *pdu, 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 = host_dev_to_dotl_dev(stbuf->st_rdev);
+    v9lstat->st_size = stbuf->st_size;
+    v9lstat->st_blksize = stat_to_iounit(pdu, stbuf);
+    v9lstat->st_blocks = stbuf->st_blocks;
+    v9lstat->st_atime_sec = stbuf->st_atime;
+    v9lstat->st_mtime_sec = stbuf->st_mtime;
+    v9lstat->st_ctime_sec = stbuf->st_ctime;
+#ifdef CONFIG_DARWIN
+    v9lstat->st_atime_nsec = stbuf->st_atimespec.tv_nsec;
+    v9lstat->st_mtime_nsec = stbuf->st_mtimespec.tv_nsec;
+    v9lstat->st_ctime_nsec = stbuf->st_ctimespec.tv_nsec;
+#else
+    v9lstat->st_atime_nsec = stbuf->st_atim.tv_nsec;
+    v9lstat->st_mtime_nsec = stbuf->st_mtim.tv_nsec;
+    v9lstat->st_ctime_nsec = stbuf->st_ctim.tv_nsec;
+#endif
+    /* Currently we only support BASIC fields in stat */
+    v9lstat->st_result_mask = P9_STATS_BASIC;
+
+    return stat_to_qid(pdu, 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_path_sprintf(dst, "%s%s", src->data, str.data + len);
+    v9fs_path_free(&str);
+}
+
+static inline bool is_ro_export(FsContext *ctx)
+{
+    return ctx->export_flags & V9FS_RDONLY;
+}
+
+static void coroutine_fn 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) {
+        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");
+        /* skip min. msize check, reporting invalid version has priority */
+        goto marshal;
+    }
+
+    if (s->msize < P9_MIN_MSIZE) {
+        err = -EMSGSIZE;
+        error_report(
+            "9pfs: Client requested msize < minimum msize ("
+            stringify(P9_MIN_MSIZE) ") supported by this server."
+        );
+        goto out;
+    }
+
+    /* 8192 is the default msize of Linux clients */
+    if (s->msize <= 8192 && !(s->ctx.export_flags & V9FS_NO_PERF_WARN)) {
+        warn_report_once(
+            "9p: degraded performance: a reasonable high msize should be "
+            "chosen on client/guest side (chosen msize is <= 8192). See "
+            "https://wiki.qemu.org/Documentation/9psetup#msize for details."
+        );
+    }
+
+marshal:
+    err = pdu_marshal(pdu, offset, "ds", s->msize, &version);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_version_return(pdu->tag, pdu->id, s->msize, version.data);
+out:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&version);
+}
+
+static void coroutine_fn 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;
+    struct stat stbuf;
+
+    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 = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (err < 0) {
+        err = -EINVAL;
+        clunk_fid(s, fid);
+        goto out;
+    }
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        err = -EINVAL;
+        clunk_fid(s, fid);
+        goto out;
+    }
+
+    /*
+     * disable migration if we haven't done already.
+     * attach could get called multiple times for the same export.
+     */
+    if (!s->migration_blocker) {
+        error_setg(&s->migration_blocker,
+                   "Migration is disabled when VirtFS export path '%s' is mounted in the guest using mount_tag '%s'",
+                   s->ctx.fs_root ? s->ctx.fs_root : "NULL", s->tag);
+        err = migrate_add_blocker(s->migration_blocker, NULL);
+        if (err < 0) {
+            error_free(s->migration_blocker);
+            s->migration_blocker = NULL;
+            clunk_fid(s, fid);
+            goto out;
+        }
+        s->root_fid = fid;
+    }
+
+    err = pdu_marshal(pdu, offset, "Q", &qid);
+    if (err < 0) {
+        clunk_fid(s, fid);
+        goto out;
+    }
+    err += offset;
+
+    memcpy(&s->root_st, &stbuf, sizeof(stbuf));
+    trace_v9fs_attach_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(&uname);
+    v9fs_string_free(&aname);
+}
+
+static void coroutine_fn 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;
+    char *basename;
+
+    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;
+    }
+    basename = g_path_get_basename(fidp->path.data);
+    err = stat_to_v9stat(pdu, &fidp->path, basename, &stbuf, &v9stat);
+    g_free(basename);
+    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 coroutine_fn 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;
+
+    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;
+    }
+    retval = stat_to_v9stat_dotl(pdu, &stbuf, &v9stat_dotl);
+    if (retval < 0) {
+        goto out;
+    }
+
+    /*  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);
+        switch (retval) {
+        case 0:
+            /* we have valid st_gen: update result mask */
+            v9stat_dotl.st_result_mask |= P9_STATS_GEN;
+            break;
+        case -EINTR:
+            /* request cancelled, e.g. by Tflush */
+            goto out;
+        default:
+            /* failed to get st_gen: not fatal, ignore */
+            break;
+        }
+    }
+    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 coroutine_fn 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;
+    }
+
+    trace_v9fs_setattr(pdu->tag, pdu->id, fid,
+                       v9iattr.valid, v9iattr.mode, v9iattr.uid, v9iattr.gid,
+                       v9iattr.size, v9iattr.atime_sec, v9iattr.mtime_sec);
+
+    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;
+    trace_v9fs_setattr_return(pdu->tag, pdu->id);
+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 bool name_is_illegal(const char *name)
+{
+    return !*name || strchr(name, '/') != NULL;
+}
+
+static bool same_stat_id(const struct stat *a, const struct stat *b)
+{
+    return a->st_dev == b->st_dev && a->st_ino == b->st_ino;
+}
+
+static void coroutine_fn v9fs_walk(void *opaque)
+{
+    int name_idx, nwalked;
+    g_autofree V9fsQID *qids = NULL;
+    int i, err = 0, any_err = 0;
+    V9fsPath dpath, path;
+    P9ARRAY_REF(V9fsPath) pathes = NULL;
+    uint16_t nwnames;
+    struct stat stbuf, fidst;
+    g_autofree struct stat *stbufs = NULL;
+    size_t offset = 7;
+    int32_t fid, newfid;
+    P9ARRAY_REF(V9fsString) wnames = NULL;
+    V9fsFidState *fidp;
+    V9fsFidState *newfidp = NULL;
+    V9fsPDU *pdu = opaque;
+    V9fsState *s = pdu->s;
+    V9fsQID qid;
+
+    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 > P9_MAXWELEM) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (nwnames) {
+        P9ARRAY_NEW(V9fsString, wnames, nwnames);
+        qids   = g_new0(V9fsQID, nwnames);
+        stbufs = g_new0(struct stat, nwnames);
+        P9ARRAY_NEW(V9fsPath, pathes, nwnames);
+        for (i = 0; i < nwnames; i++) {
+            err = pdu_unmarshal(pdu, offset, "s", &wnames[i]);
+            if (err < 0) {
+                goto out_nofid;
+            }
+            if (name_is_illegal(wnames[i].data)) {
+                err = -ENOENT;
+                goto out_nofid;
+            }
+            offset += err;
+        }
+    }
+    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 point to fidp.
+     * Needed to handle request with nwnames == 0
+     */
+    v9fs_path_copy(&dpath, &fidp->path);
+    v9fs_path_copy(&path, &fidp->path);
+
+    /*
+     * To keep latency (i.e. overall execution time for processing this
+     * Twalk client request) as small as possible, run all the required fs
+     * driver code altogether inside the following block.
+     */
+    v9fs_co_run_in_worker({
+        nwalked = 0;
+        if (v9fs_request_cancelled(pdu)) {
+            any_err |= err = -EINTR;
+            break;
+        }
+        err = s->ops->lstat(&s->ctx, &dpath, &fidst);
+        if (err < 0) {
+            any_err |= err = -errno;
+            break;
+        }
+        stbuf = fidst;
+        for (; nwalked < nwnames; nwalked++) {
+            if (v9fs_request_cancelled(pdu)) {
+                any_err |= err = -EINTR;
+                break;
+            }
+            if (!same_stat_id(&pdu->s->root_st, &stbuf) ||
+                strcmp("..", wnames[nwalked].data))
+            {
+                err = s->ops->name_to_path(&s->ctx, &dpath,
+                                           wnames[nwalked].data,
+                                           &pathes[nwalked]);
+                if (err < 0) {
+                    any_err |= err = -errno;
+                    break;
+                }
+                if (v9fs_request_cancelled(pdu)) {
+                    any_err |= err = -EINTR;
+                    break;
+                }
+                err = s->ops->lstat(&s->ctx, &pathes[nwalked], &stbuf);
+                if (err < 0) {
+                    any_err |= err = -errno;
+                    break;
+                }
+                stbufs[nwalked] = stbuf;
+                v9fs_path_copy(&dpath, &pathes[nwalked]);
+            }
+        }
+    });
+    /*
+     * Handle all the rest of this Twalk request on main thread ...
+     *
+     * NOTE: -EINTR is an exception where we deviate from the protocol spec
+     * and simply send a (R)Lerror response instead of bothering to assemble
+     * a (deducted) Rwalk response; because -EINTR is always the result of a
+     * Tflush request, so client would no longer wait for a response in this
+     * case anyway.
+     */
+    if ((err < 0 && !nwalked) || err == -EINTR) {
+        goto out;
+    }
+
+    any_err |= err = stat_to_qid(pdu, &fidst, &qid);
+    if (err < 0 && !nwalked) {
+        goto out;
+    }
+    stbuf = fidst;
+
+    /* reset dpath and path */
+    v9fs_path_copy(&dpath, &fidp->path);
+    v9fs_path_copy(&path, &fidp->path);
+
+    for (name_idx = 0; name_idx < nwalked; name_idx++) {
+        if (!same_stat_id(&pdu->s->root_st, &stbuf) ||
+            strcmp("..", wnames[name_idx].data))
+        {
+            stbuf = stbufs[name_idx];
+            any_err |= err = stat_to_qid(pdu, &stbuf, &qid);
+            if (err < 0) {
+                break;
+            }
+            v9fs_path_copy(&path, &pathes[name_idx]);
+            v9fs_path_copy(&dpath, &path);
+        }
+        memcpy(&qids[name_idx], &qid, sizeof(qid));
+    }
+    if (any_err < 0) {
+        if (!name_idx) {
+            /* don't send any QIDs, send Rlerror instead */
+            goto out;
+        } else {
+            /* send QIDs (not Rlerror), but fid MUST remain unaffected */
+            goto send_qids;
+        }
+    }
+    if (fid == newfid) {
+        if (fidp->fid_type != P9_FID_NONE) {
+            err = -EINVAL;
+            goto out;
+        }
+        v9fs_path_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+    } else {
+        newfidp = alloc_fid(s, newfid);
+        if (newfidp == NULL) {
+            err = -EINVAL;
+            goto out;
+        }
+        newfidp->uid = fidp->uid;
+        v9fs_path_copy(&newfidp->path, &path);
+    }
+send_qids:
+    err = v9fs_walk_marshal(pdu, name_idx, qids);
+    trace_v9fs_walk_return(pdu->tag, pdu->id, name_idx, 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);
+}
+
+static int32_t coroutine_fn get_iounit(V9fsPDU *pdu, V9fsPath *path)
+{
+    struct statfs stbuf;
+    int err = v9fs_co_statfs(pdu, path, &stbuf);
+
+    return blksize_to_iounit(pdu, (err >= 0) ? stbuf.f_bsize : 0);
+}
+
+static void coroutine_fn 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;
+    }
+    if (fidp->fid_type != P9_FID_NONE) {
+        err = -EINVAL;
+        goto out;
+    }
+
+    err = v9fs_co_lstat(pdu, &fidp->path, &stbuf);
+    if (err < 0) {
+        goto out;
+    }
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn 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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    fidp = get_fid(pdu, dfid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    if (fidp->fid_type != P9_FID_NONE) {
+        err = -EINVAL;
+        goto out;
+    }
+
+    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);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn 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 coroutine_fn 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);
+}
+
+/*
+ * 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;
+
+    if (is_write) {
+        pdu->s->transport->init_out_iov_from_pdu(pdu, &iov, &niov, size + skip);
+    } else {
+        pdu->s->transport->init_in_iov_from_pdu(pdu, &iov, &niov, size + skip);
+    }
+
+    qemu_iovec_init_external(&elem, iov, niov);
+    qemu_iovec_init(qiov, niov);
+    qemu_iovec_concat(qiov, &elem, skip, size);
+}
+
+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;
+    uint64_t read_count;
+    QEMUIOVector qiov_full;
+
+    if (fidp->fs.xattr.len < off) {
+        read_count = 0;
+    } else {
+        read_count = fidp->fs.xattr.len - off;
+    }
+    if (read_count > max_count) {
+        read_count = max_count;
+    }
+    err = pdu_marshal(pdu, offset, "d", read_count);
+    if (err < 0) {
+        return err;
+    }
+    offset += err;
+
+    v9fs_init_qiov_from_pdu(&qiov_full, pdu, offset, read_count, false);
+    err = v9fs_pack(qiov_full.iov, qiov_full.niov, 0,
+                    ((char *)fidp->fs.xattr.value) + off,
+                    read_count);
+    qemu_iovec_destroy(&qiov_full);
+    if (err < 0) {
+        return err;
+    }
+    offset += err;
+    return offset;
+}
+
+static int coroutine_fn 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;
+
+    /* save the directory position */
+    saved_dir_pos = v9fs_co_telldir(pdu, fidp);
+    if (saved_dir_pos < 0) {
+        return saved_dir_pos;
+    }
+
+    while (1) {
+        v9fs_path_init(&path);
+
+        v9fs_readdir_lock(&fidp->fs.dir);
+
+        err = v9fs_co_readdir(pdu, fidp, &dent);
+        if (err || !dent) {
+            break;
+        }
+        err = v9fs_co_name_to_path(pdu, &fidp->path, dent->d_name, &path);
+        if (err < 0) {
+            break;
+        }
+        err = v9fs_co_lstat(pdu, &path, &stbuf);
+        if (err < 0) {
+            break;
+        }
+        err = stat_to_v9stat(pdu, &path, dent->d_name, &stbuf, &v9stat);
+        if (err < 0) {
+            break;
+        }
+        if ((count + v9stat.size + 2) > max_count) {
+            v9fs_readdir_unlock(&fidp->fs.dir);
+
+            /* 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);
+            return count;
+        }
+
+        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
+        len = pdu_marshal(pdu, 11 + count, "S", &v9stat);
+
+        v9fs_readdir_unlock(&fidp->fs.dir);
+
+        if (len < 0) {
+            v9fs_co_seekdir(pdu, fidp, saved_dir_pos);
+            v9fs_stat_free(&v9stat);
+            v9fs_path_free(&path);
+            return len;
+        }
+        count += len;
+        v9fs_stat_free(&v9stat);
+        v9fs_path_free(&path);
+        saved_dir_pos = qemu_dirent_off(dent);
+    }
+
+    v9fs_readdir_unlock(&fidp->fs.dir);
+
+    v9fs_path_free(&path);
+    if (err < 0) {
+        return err;
+    }
+    return count;
+}
+
+static void coroutine_fn 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 (s->proto_version != V9FS_PROTO_2000U) {
+            warn_report_once(
+                "9p: bad client: T_read request on directory only expected "
+                "with 9P2000.u protocol version"
+            );
+            err = -EOPNOTSUPP;
+            goto out;
+        }
+        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_free_iovec;
+            }
+        } while (count < max_count && len > 0);
+        err = pdu_marshal(pdu, offset, "d", count);
+        if (err < 0) {
+            goto out_free_iovec;
+        }
+        err += offset + count;
+out_free_iovec:
+        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);
+}
+
+/**
+ * v9fs_readdir_response_size() - Returns size required in Rreaddir response
+ * for the passed dirent @name.
+ *
+ * @name: directory entry's name (i.e. file name, directory name)
+ * Return: required size in bytes
+ */
+size_t v9fs_readdir_response_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 void v9fs_free_dirents(struct V9fsDirEnt *e)
+{
+    struct V9fsDirEnt *next = NULL;
+
+    for (; e; e = next) {
+        next = e->next;
+        g_free(e->dent);
+        g_free(e->st);
+        g_free(e);
+    }
+}
+
+static int coroutine_fn v9fs_do_readdir(V9fsPDU *pdu, V9fsFidState *fidp,
+                                        off_t offset, int32_t max_count)
+{
+    size_t size;
+    V9fsQID qid;
+    V9fsString name;
+    int len, err = 0;
+    int32_t count = 0;
+    off_t off;
+    struct dirent *dent;
+    struct stat *st;
+    struct V9fsDirEnt *entries = NULL;
+
+    /*
+     * inode remapping requires the device id, which in turn might be
+     * different for different directory entries, so if inode remapping is
+     * enabled we have to make a full stat for each directory entry
+     */
+    const bool dostat = pdu->s->ctx.export_flags & V9FS_REMAP_INODES;
+
+    /*
+     * Fetch all required directory entries altogether on a background IO
+     * thread from fs driver. We don't want to do that for each entry
+     * individually, because hopping between threads (this main IO thread
+     * and background IO driver thread) would sum up to huge latencies.
+     */
+    count = v9fs_co_readdir_many(pdu, fidp, &entries, offset, max_count,
+                                 dostat);
+    if (count < 0) {
+        err = count;
+        count = 0;
+        goto out;
+    }
+    count = 0;
+
+    for (struct V9fsDirEnt *e = entries; e; e = e->next) {
+        dent = e->dent;
+
+        if (pdu->s->ctx.export_flags & V9FS_REMAP_INODES) {
+            st = e->st;
+            /* e->st should never be NULL, but just to be sure */
+            if (!st) {
+                err = -1;
+                break;
+            }
+
+            /* remap inode */
+            err = stat_to_qid(pdu, st, &qid);
+            if (err < 0) {
+                break;
+            }
+        } else {
+            /*
+             * 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. For the
+             * latter reason we don't call stat_to_qid() here. Only drawback
+             * is that no multi-device export detection of stat_to_qid()
+             * would be done and provided as error to the user here. But
+             * user would get that error anyway when accessing those
+             * files/dirs through other ways.
+             */
+            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;
+        }
+
+        off = qemu_dirent_off(dent);
+        v9fs_string_init(&name);
+        v9fs_string_sprintf(&name, "%s", dent->d_name);
+
+        /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */
+        len = pdu_marshal(pdu, 11 + count, "Qqbs",
+                          &qid, off,
+                          dent->d_type, &name);
+
+        v9fs_string_free(&name);
+
+        if (len < 0) {
+            err = len;
+            break;
+        }
+
+        count += len;
+    }
+
+out:
+    v9fs_free_dirents(entries);
+    if (err < 0) {
+        return err;
+    }
+    return count;
+}
+
+static void coroutine_fn 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;
+    V9fsState *s = pdu->s;
+
+    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);
+
+    /* Enough space for a R_readdir header: size[4] Rreaddir tag[2] count[4] */
+    if (max_count > s->msize - 11) {
+        max_count = s->msize - 11;
+        warn_report_once(
+            "9p: bad client: T_readdir with count > msize - 11"
+        );
+    }
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        retval = -EINVAL;
+        goto out_nofid;
+    }
+    if (!fidp->fs.dir.stream) {
+        retval = -EINVAL;
+        goto out;
+    }
+    if (s->proto_version != V9FS_PROTO_2000L) {
+        warn_report_once(
+            "9p: bad client: T_readdir request only expected with 9P2000.L "
+            "protocol version"
+        );
+        retval = -EOPNOTSUPP;
+        goto out;
+    }
+    count = v9fs_do_readdir(pdu, fidp, (off_t) initial_offset, 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;
+    uint64_t write_count;
+    size_t offset = 7;
+
+
+    if (fidp->fs.xattr.len < off) {
+        return -ENOSPC;
+    }
+    write_count = fidp->fs.xattr.len - off;
+    if (write_count > count) {
+        write_count = count;
+    }
+    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;
+    }
+
+    return err;
+}
+
+static void coroutine_fn 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_qiov;
+    }
+    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 coroutine_fn 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;
+    V9fsState *s = pdu->s;
+
+    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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (fidp->fid_type != P9_FID_NONE) {
+        err = -EINVAL;
+        goto out;
+    }
+    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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+        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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+    } 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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+        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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+    } 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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+    } 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_write_lock(s);
+        v9fs_path_copy(&fidp->path, &path);
+        v9fs_path_unlock(s);
+    } 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);
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn 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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    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;
+    }
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn v9fs_flush(void *opaque)
+{
+    ssize_t err;
+    int16_t tag;
+    size_t offset = 7;
+    V9fsPDU *cancel_pdu = NULL;
+    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);
+
+    if (pdu->tag == tag) {
+        warn_report("the guest sent a self-referencing 9P flush request");
+    } else {
+        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, NULL);
+        if (!qemu_co_queue_next(&cancel_pdu->complete)) {
+            cancel_pdu->cancelled = 0;
+            pdu_free(cancel_pdu);
+        }
+    }
+    pdu_complete(pdu, 7);
+}
+
+static void coroutine_fn 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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    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;
+    }
+    put_fid(pdu, oldfidp);
+out:
+    put_fid(pdu, dfidp);
+out_nofid:
+    v9fs_string_free(&name);
+    pdu_complete(pdu, err);
+}
+
+/* Only works with path name based fid */
+static void coroutine_fn 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 coroutine_fn v9fs_unlinkat(void *opaque)
+{
+    int err = 0;
+    V9fsString name;
+    int32_t dfid, flags, rflags = 0;
+    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;
+    }
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data)) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+
+    if (!strcmp("..", name.data)) {
+        err = -ENOTEMPTY;
+        goto out_nofid;
+    }
+
+    if (flags & ~P9_DOTL_AT_REMOVEDIR) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+
+    if (flags & P9_DOTL_AT_REMOVEDIR) {
+        rflags |= AT_REMOVEDIR;
+    }
+
+    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, rflags);
+    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 coroutine_fn v9fs_complete_rename(V9fsPDU *pdu, V9fsFidState *fidp,
+                                             int32_t newdirfid,
+                                             V9fsString *name)
+{
+    int err = 0;
+    V9fsPath new_path;
+    V9fsFidState *tfidp;
+    V9fsState *s = pdu->s;
+    V9fsFidState *dirfidp = NULL;
+    GHashTableIter iter;
+    gpointer fid;
+
+    v9fs_path_init(&new_path);
+    if (newdirfid != -1) {
+        dirfidp = get_fid(pdu, newdirfid);
+        if (dirfidp == NULL) {
+            return -ENOENT;
+        }
+        if (fidp->fid_type != P9_FID_NONE) {
+            err = -EINVAL;
+            goto out;
+        }
+        err = v9fs_co_name_to_path(pdu, &dirfidp->path, name->data, &new_path);
+        if (err < 0) {
+            goto out;
+        }
+    } else {
+        char *dir_name = g_path_get_dirname(fidp->path.data);
+        V9fsPath dir_path;
+
+        v9fs_path_init(&dir_path);
+        v9fs_path_sprintf(&dir_path, "%s", dir_name);
+        g_free(dir_name);
+
+        err = v9fs_co_name_to_path(pdu, &dir_path, name->data, &new_path);
+        v9fs_path_free(&dir_path);
+        if (err < 0) {
+            goto out;
+        }
+    }
+    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
+     */
+    g_hash_table_iter_init(&iter, s->fids);
+    while (g_hash_table_iter_next(&iter, &fid, (gpointer *) &tfidp)) {
+        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);
+    return err;
+}
+
+/* Only works with path name based fid */
+static void coroutine_fn 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;
+    }
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EISDIR;
+        goto out_nofid;
+    }
+
+    fidp = get_fid(pdu, fid);
+    if (fidp == NULL) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+    if (fidp->fid_type != P9_FID_NONE) {
+        err = -EINVAL;
+        goto out;
+    }
+    /* 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 int coroutine_fn 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;
+    int err;
+    GHashTableIter iter;
+    gpointer fid;
+
+    v9fs_path_init(&oldpath);
+    v9fs_path_init(&newpath);
+    err = v9fs_co_name_to_path(pdu, olddir, old_name->data, &oldpath);
+    if (err < 0) {
+        goto out;
+    }
+    err = v9fs_co_name_to_path(pdu, newdir, new_name->data, &newpath);
+    if (err < 0) {
+        goto out;
+    }
+
+    /*
+     * Fixup fid's pointing to the old name to
+     * start pointing to the new name
+     */
+    g_hash_table_iter_init(&iter, s->fids);
+    while (g_hash_table_iter_next(&iter, &fid, (gpointer *) &tfidp)) {
+        if (v9fs_path_is_ancestor(&oldpath, &tfidp->path)) {
+            /* replace the name */
+            v9fs_fix_path(&tfidp->path, &newpath, strlen(oldpath.data));
+        }
+    }
+out:
+    v9fs_path_free(&oldpath);
+    v9fs_path_free(&newpath);
+    return err;
+}
+
+static int coroutine_fn 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 */
+        err = 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 coroutine_fn 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;
+    }
+
+    if (name_is_illegal(old_name.data) || name_is_illegal(new_name.data)) {
+        err = -ENOENT;
+        goto out_err;
+    }
+
+    if (!strcmp(".", old_name.data) || !strcmp("..", old_name.data) ||
+        !strcmp(".", new_name.data) || !strcmp("..", new_name.data)) {
+        err = -EISDIR;
+        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 coroutine_fn 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;
+    V9fsState *s = pdu->s;
+
+    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) {
+        v9fs_path_write_lock(s);
+        err = v9fs_complete_rename(pdu, fidp, -1, &v9stat.name);
+        v9fs_path_unlock(s);
+        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;
+#ifdef CONFIG_DARWIN
+    fsid_val = (unsigned int)stbuf->f_fsid.val[0] |
+               (unsigned long long)stbuf->f_fsid.val[1] << 32;
+    f_namelen = NAME_MAX;
+#else
+    fsid_val = (unsigned int) stbuf->f_fsid.__val[0] |
+               (unsigned long long)stbuf->f_fsid.__val[1] << 32;
+    f_namelen = stbuf->f_namelen;
+#endif
+
+    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 coroutine_fn 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 coroutine_fn 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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    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;
+    }
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn v9fs_lock(void *opaque)
+{
+    V9fsFlock flock;
+    size_t offset = 7;
+    struct stat stbuf;
+    V9fsFidState *fidp;
+    int32_t fid, err = 0;
+    V9fsPDU *pdu = opaque;
+
+    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;
+    }
+    err = pdu_marshal(pdu, offset, "b", P9_LOCK_SUCCESS);
+    if (err < 0) {
+        goto out;
+    }
+    err += offset;
+    trace_v9fs_lock_return(pdu->tag, pdu->id, P9_LOCK_SUCCESS);
+out:
+    put_fid(pdu, fidp);
+out_nofid:
+    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 coroutine_fn 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 coroutine_fn 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);
+
+    if (name_is_illegal(name.data)) {
+        err = -ENOENT;
+        goto out_nofid;
+    }
+
+    if (!strcmp(".", name.data) || !strcmp("..", name.data)) {
+        err = -EEXIST;
+        goto out_nofid;
+    }
+
+    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;
+    }
+    err = stat_to_qid(pdu, &stbuf, &qid);
+    if (err < 0) {
+        goto out;
+    }
+    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 coroutine_fn 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 (!v9fs_string_size(&name)) {
+        /*
+         * 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.xattrwalk_fid = true;
+        xattr_fidp->fs.xattr.value = g_malloc0(size);
+        if (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.xattrwalk_fid = true;
+        xattr_fidp->fs.xattr.value = g_malloc0(size);
+        if (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);
+}
+
+#if defined(CONFIG_LINUX)
+/* Currently, only Linux has XATTR_SIZE_MAX */
+#define P9_XATTR_SIZE_MAX XATTR_SIZE_MAX
+#elif defined(CONFIG_DARWIN)
+/*
+ * Darwin doesn't seem to define a maximum xattr size in its user
+ * space header, so manually configure it across platforms as 64k.
+ *
+ * Having no limit at all can lead to QEMU crashing during large g_malloc()
+ * calls. Because QEMU does not currently support macOS guests, the below
+ * preliminary solution only works due to its being a reflection of the limit of
+ * Linux guests.
+ */
+#define P9_XATTR_SIZE_MAX 65536
+#else
+#error Missing definition for P9_XATTR_SIZE_MAX for this host system
+#endif
+
+static void coroutine_fn v9fs_xattrcreate(void *opaque)
+{
+    int flags, rflags = 0;
+    int32_t fid;
+    uint64_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);
+
+    if (flags & ~(P9_XATTR_CREATE | P9_XATTR_REPLACE)) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+
+    if (flags & P9_XATTR_CREATE) {
+        rflags |= XATTR_CREATE;
+    }
+
+    if (flags & P9_XATTR_REPLACE) {
+        rflags |= XATTR_REPLACE;
+    }
+
+    if (size > P9_XATTR_SIZE_MAX) {
+        err = -E2BIG;
+        goto out_nofid;
+    }
+
+    file_fidp = get_fid(pdu, fid);
+    if (file_fidp == NULL) {
+        err = -EINVAL;
+        goto out_nofid;
+    }
+    if (file_fidp->fid_type != P9_FID_NONE) {
+        err = -EINVAL;
+        goto out_put_fid;
+    }
+
+    /* 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.xattrwalk_fid = false;
+    xattr_fidp->fs.xattr.len = size;
+    xattr_fidp->fs.xattr.flags = rflags;
+    v9fs_string_init(&xattr_fidp->fs.xattr.name);
+    v9fs_string_copy(&xattr_fidp->fs.xattr.name, &name);
+    xattr_fidp->fs.xattr.value = g_malloc0(size);
+    err = offset;
+out_put_fid:
+    put_fid(pdu, file_fidp);
+out_nofid:
+    pdu_complete(pdu, err);
+    v9fs_string_free(&name);
+}
+
+static void coroutine_fn 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 coroutine_fn v9fs_op_not_supp(void *opaque)
+{
+    V9fsPDU *pdu = opaque;
+    pdu_complete(pdu, -EOPNOTSUPP);
+}
+
+static void coroutine_fn 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, P9MsgHeader *hdr)
+{
+    Coroutine *co;
+    CoroutineEntry *handler;
+    V9fsState *s = pdu->s;
+
+    pdu->size = le32_to_cpu(hdr->size_le);
+    pdu->id = hdr->id;
+    pdu->tag = le16_to_cpu(hdr->tag_le);
+
+    if (pdu->id >= ARRAY_SIZE(pdu_co_handlers) ||
+        (pdu_co_handlers[pdu->id] == NULL)) {
+        handler = v9fs_op_not_supp;
+    } else if (is_ro_export(&s->ctx) && !is_read_only_op(pdu)) {
+        handler = v9fs_fs_ro;
+    } else {
+        handler = pdu_co_handlers[pdu->id];
+    }
+
+    qemu_co_queue_init(&pdu->complete);
+    co = qemu_coroutine_create(handler, pdu);
+    qemu_coroutine_enter(co);
+}
+
+/* Returns 0 on success, 1 on failure. */
+int v9fs_device_realize_common(V9fsState *s, const V9fsTransport *t,
+                               Error **errp)
+{
+    ERRP_GUARD();
+    int i, len;
+    struct stat stat;
+    FsDriverEntry *fse;
+    V9fsPath path;
+    int rc = 1;
+
+    assert(!s->transport);
+    s->transport = t;
+
+    /* initialize pdu allocator */
+    QLIST_INIT(&s->free_list);
+    QLIST_INIT(&s->active_list);
+    for (i = 0; i < MAX_REQ; i++) {
+        QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
+        s->pdus[i].s = s;
+        s->pdus[i].idx = i;
+    }
+
+    v9fs_path_init(&path);
+
+    fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
+
+    if (!fse) {
+        /* We don't have a fsdev identified by fsdev_id */
+        error_setg(errp, "9pfs device couldn't find fsdev with the "
+                   "id = %s",
+                   s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL");
+        goto out;
+    }
+
+    if (!s->fsconf.tag) {
+        /* we haven't specified a mount_tag */
+        error_setg(errp, "fsdev with id %s needs mount_tag arguments",
+                   s->fsconf.fsdev_id);
+        goto out;
+    }
+
+    s->ctx.export_flags = fse->export_flags;
+    s->ctx.fs_root = g_strdup(fse->path);
+    s->ctx.exops.get_st_gen = NULL;
+    len = strlen(s->fsconf.tag);
+    if (len > MAX_TAG_LEN - 1) {
+        error_setg(errp, "mount tag '%s' (%d bytes) is longer than "
+                   "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1);
+        goto out;
+    }
+
+    s->tag = g_strdup(s->fsconf.tag);
+    s->ctx.uid = -1;
+
+    s->ops = fse->ops;
+
+    s->ctx.fmode = fse->fmode;
+    s->ctx.dmode = fse->dmode;
+
+    s->fids = g_hash_table_new(NULL, NULL);
+    qemu_co_rwlock_init(&s->rename_lock);
+
+    if (s->ops->init(&s->ctx, errp) < 0) {
+        error_prepend(errp, "cannot initialize fsdev '%s': ",
+                      s->fsconf.fsdev_id);
+        goto out;
+    }
+
+    /*
+     * Check details of export path, We need to use fs driver
+     * call back to do that. Since we are in the init path, we don't
+     * use co-routines here.
+     */
+    if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
+        error_setg(errp,
+                   "error in converting name to path %s", strerror(errno));
+        goto out;
+    }
+    if (s->ops->lstat(&s->ctx, &path, &stat)) {
+        error_setg(errp, "share path %s does not exist", fse->path);
+        goto out;
+    } else if (!S_ISDIR(stat.st_mode)) {
+        error_setg(errp, "share path %s is not a directory", fse->path);
+        goto out;
+    }
+
+    s->dev_id = stat.st_dev;
+
+    /* init inode remapping : */
+    /* hash table for variable length inode suffixes */
+    qpd_table_init(&s->qpd_table);
+    /* hash table for slow/full inode remapping (most users won't need it) */
+    qpf_table_init(&s->qpf_table);
+    /* hash table for quick inode remapping */
+    qpp_table_init(&s->qpp_table);
+    s->qp_ndevices = 0;
+    s->qp_affix_next = 1; /* reserve 0 to detect overflow */
+    s->qp_fullpath_next = 1;
+
+    s->ctx.fst = &fse->fst;
+    fsdev_throttle_init(s->ctx.fst);
+
+    rc = 0;
+out:
+    if (rc) {
+        v9fs_device_unrealize_common(s);
+    }
+    v9fs_path_free(&path);
+    return rc;
+}
+
+void v9fs_device_unrealize_common(V9fsState *s)
+{
+    if (s->ops && s->ops->cleanup) {
+        s->ops->cleanup(&s->ctx);
+    }
+    if (s->ctx.fst) {
+        fsdev_throttle_cleanup(s->ctx.fst);
+    }
+    if (s->fids) {
+        g_hash_table_destroy(s->fids);
+        s->fids = NULL;
+    }
+    g_free(s->tag);
+    qp_table_destroy(&s->qpd_table);
+    qp_table_destroy(&s->qpp_table);
+    qp_table_destroy(&s->qpf_table);
+    g_free(s->ctx.fs_root);
+}
+
+typedef struct VirtfsCoResetData {
+    V9fsPDU pdu;
+    bool done;
+} VirtfsCoResetData;
+
+static void coroutine_fn virtfs_co_reset(void *opaque)
+{
+    VirtfsCoResetData *data = opaque;
+
+    virtfs_reset(&data->pdu);
+    data->done = true;
+}
+
+void v9fs_reset(V9fsState *s)
+{
+    VirtfsCoResetData data = { .pdu = { .s = s }, .done = false };
+    Coroutine *co;
+
+    while (!QLIST_EMPTY(&s->active_list)) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+
+    co = qemu_coroutine_create(virtfs_co_reset, &data);
+    qemu_coroutine_enter(co);
+
+    while (!data.done) {
+        aio_poll(qemu_get_aio_context(), true);
+    }
+}
+
+static void __attribute__((__constructor__)) v9fs_set_fd_limit(void)
+{
+    struct rlimit rlim;
+    if (getrlimit(RLIMIT_NOFILE, &rlim) < 0) {
+        error_report("Failed to get the resource limit");
+        exit(1);
+    }
+    open_fd_hw = rlim.rlim_cur - MIN(400, rlim.rlim_cur / 3);
+    open_fd_rc = rlim.rlim_cur / 2;
+}