9pfs: rename virtio-9p-local.c to 9p-local.c

This file is not virtio specific. Rename it to use generic name.

Fix comment and remove unneeded inclusion of virtio.h.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

1 files changed, 1279 insertions, 0 deletions

diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
new file mode 100644
index 0000000000..877ad86c7a
--- /dev/null
+++ b/hw/9pfs/9p-local.c
@@ -0,0 +1,1279 @@
+/*
+ * 9p Posix callback
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "virtio-9p.h"
+#include "virtio-9p-xattr.h"
+#include "fsdev/qemu-fsdev.h"   /* local_ops */
+#include <arpa/inet.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include "qemu/xattr.h"
+#include <libgen.h>
+#include <linux/fs.h>
+#ifdef CONFIG_LINUX_MAGIC_H
+#include <linux/magic.h>
+#endif
+#include <sys/ioctl.h>
+
+#ifndef XFS_SUPER_MAGIC
+#define XFS_SUPER_MAGIC  0x58465342
+#endif
+#ifndef EXT2_SUPER_MAGIC
+#define EXT2_SUPER_MAGIC 0xEF53
+#endif
+#ifndef REISERFS_SUPER_MAGIC
+#define REISERFS_SUPER_MAGIC 0x52654973
+#endif
+#ifndef BTRFS_SUPER_MAGIC
+#define BTRFS_SUPER_MAGIC 0x9123683E
+#endif
+
+#define VIRTFS_META_DIR ".virtfs_metadata"
+
+static char *local_mapped_attr_path(FsContext *ctx, const char *path)
+{
+    int dirlen;
+    const char *name = strrchr(path, '/');
+    if (name) {
+        dirlen = name - path;
+        ++name;
+    } else {
+        name = path;
+        dirlen = 0;
+    }
+    return g_strdup_printf("%s/%.*s/%s/%s", ctx->fs_root,
+                           dirlen, path, VIRTFS_META_DIR, name);
+}
+
+static FILE *local_fopen(const char *path, const char *mode)
+{
+    int fd, o_mode = 0;
+    FILE *fp;
+    int flags = O_NOFOLLOW;
+    /*
+     * only supports two modes
+     */
+    if (mode[0] == 'r') {
+        flags |= O_RDONLY;
+    } else if (mode[0] == 'w') {
+        flags |= O_WRONLY | O_TRUNC | O_CREAT;
+        o_mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
+    } else {
+        return NULL;
+    }
+    fd = open(path, flags, o_mode);
+    if (fd == -1) {
+        return NULL;
+    }
+    fp = fdopen(fd, mode);
+    if (!fp) {
+        close(fd);
+    }
+    return fp;
+}
+
+#define ATTR_MAX 100
+static void local_mapped_file_attr(FsContext *ctx, const char *path,
+                                   struct stat *stbuf)
+{
+    FILE *fp;
+    char buf[ATTR_MAX];
+    char *attr_path;
+
+    attr_path = local_mapped_attr_path(ctx, path);
+    fp = local_fopen(attr_path, "r");
+    g_free(attr_path);
+    if (!fp) {
+        return;
+    }
+    memset(buf, 0, ATTR_MAX);
+    while (fgets(buf, ATTR_MAX, fp)) {
+        if (!strncmp(buf, "virtfs.uid", 10)) {
+            stbuf->st_uid = atoi(buf+11);
+        } else if (!strncmp(buf, "virtfs.gid", 10)) {
+            stbuf->st_gid = atoi(buf+11);
+        } else if (!strncmp(buf, "virtfs.mode", 11)) {
+            stbuf->st_mode = atoi(buf+12);
+        } else if (!strncmp(buf, "virtfs.rdev", 11)) {
+            stbuf->st_rdev = atoi(buf+12);
+        }
+        memset(buf, 0, ATTR_MAX);
+    }
+    fclose(fp);
+}
+
+static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf)
+{
+    int err;
+    char *buffer;
+    char *path = fs_path->data;
+
+    buffer = rpath(fs_ctx, path);
+    err =  lstat(buffer, stbuf);
+    if (err) {
+        goto err_out;
+    }
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        /* Actual credentials are part of extended attrs */
+        uid_t tmp_uid;
+        gid_t tmp_gid;
+        mode_t tmp_mode;
+        dev_t tmp_dev;
+        if (getxattr(buffer, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) {
+            stbuf->st_uid = le32_to_cpu(tmp_uid);
+        }
+        if (getxattr(buffer, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) {
+            stbuf->st_gid = le32_to_cpu(tmp_gid);
+        }
+        if (getxattr(buffer, "user.virtfs.mode",
+                    &tmp_mode, sizeof(mode_t)) > 0) {
+            stbuf->st_mode = le32_to_cpu(tmp_mode);
+        }
+        if (getxattr(buffer, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) {
+            stbuf->st_rdev = le64_to_cpu(tmp_dev);
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        local_mapped_file_attr(fs_ctx, path, stbuf);
+    }
+
+err_out:
+    g_free(buffer);
+    return err;
+}
+
+static int local_create_mapped_attr_dir(FsContext *ctx, const char *path)
+{
+    int err;
+    char *attr_dir;
+    char *tmp_path = g_strdup(path);
+
+    attr_dir = g_strdup_printf("%s/%s/%s",
+             ctx->fs_root, dirname(tmp_path), VIRTFS_META_DIR);
+
+    err = mkdir(attr_dir, 0700);
+    if (err < 0 && errno == EEXIST) {
+        err = 0;
+    }
+    g_free(attr_dir);
+    g_free(tmp_path);
+    return err;
+}
+
+static int local_set_mapped_file_attr(FsContext *ctx,
+                                      const char *path, FsCred *credp)
+{
+    FILE *fp;
+    int ret = 0;
+    char buf[ATTR_MAX];
+    char *attr_path;
+    int uid = -1, gid = -1, mode = -1, rdev = -1;
+
+    attr_path = local_mapped_attr_path(ctx, path);
+    fp = local_fopen(attr_path, "r");
+    if (!fp) {
+        goto create_map_file;
+    }
+    memset(buf, 0, ATTR_MAX);
+    while (fgets(buf, ATTR_MAX, fp)) {
+        if (!strncmp(buf, "virtfs.uid", 10)) {
+            uid = atoi(buf+11);
+        } else if (!strncmp(buf, "virtfs.gid", 10)) {
+            gid = atoi(buf+11);
+        } else if (!strncmp(buf, "virtfs.mode", 11)) {
+            mode = atoi(buf+12);
+        } else if (!strncmp(buf, "virtfs.rdev", 11)) {
+            rdev = atoi(buf+12);
+        }
+        memset(buf, 0, ATTR_MAX);
+    }
+    fclose(fp);
+    goto update_map_file;
+
+create_map_file:
+    ret = local_create_mapped_attr_dir(ctx, path);
+    if (ret < 0) {
+        goto err_out;
+    }
+
+update_map_file:
+    fp = local_fopen(attr_path, "w");
+    if (!fp) {
+        ret = -1;
+        goto err_out;
+    }
+
+    if (credp->fc_uid != -1) {
+        uid = credp->fc_uid;
+    }
+    if (credp->fc_gid != -1) {
+        gid = credp->fc_gid;
+    }
+    if (credp->fc_mode != -1) {
+        mode = credp->fc_mode;
+    }
+    if (credp->fc_rdev != -1) {
+        rdev = credp->fc_rdev;
+    }
+
+
+    if (uid != -1) {
+        fprintf(fp, "virtfs.uid=%d\n", uid);
+    }
+    if (gid != -1) {
+        fprintf(fp, "virtfs.gid=%d\n", gid);
+    }
+    if (mode != -1) {
+        fprintf(fp, "virtfs.mode=%d\n", mode);
+    }
+    if (rdev != -1) {
+        fprintf(fp, "virtfs.rdev=%d\n", rdev);
+    }
+    fclose(fp);
+
+err_out:
+    g_free(attr_path);
+    return ret;
+}
+
+static int local_set_xattr(const char *path, FsCred *credp)
+{
+    int err;
+
+    if (credp->fc_uid != -1) {
+        uint32_t tmp_uid = cpu_to_le32(credp->fc_uid);
+        err = setxattr(path, "user.virtfs.uid", &tmp_uid, sizeof(uid_t), 0);
+        if (err) {
+            return err;
+        }
+    }
+    if (credp->fc_gid != -1) {
+        uint32_t tmp_gid = cpu_to_le32(credp->fc_gid);
+        err = setxattr(path, "user.virtfs.gid", &tmp_gid, sizeof(gid_t), 0);
+        if (err) {
+            return err;
+        }
+    }
+    if (credp->fc_mode != -1) {
+        uint32_t tmp_mode = cpu_to_le32(credp->fc_mode);
+        err = setxattr(path, "user.virtfs.mode", &tmp_mode, sizeof(mode_t), 0);
+        if (err) {
+            return err;
+        }
+    }
+    if (credp->fc_rdev != -1) {
+        uint64_t tmp_rdev = cpu_to_le64(credp->fc_rdev);
+        err = setxattr(path, "user.virtfs.rdev", &tmp_rdev, sizeof(dev_t), 0);
+        if (err) {
+            return err;
+        }
+    }
+    return 0;
+}
+
+static int local_post_create_passthrough(FsContext *fs_ctx, const char *path,
+                                         FsCred *credp)
+{
+    char *buffer;
+
+    buffer = rpath(fs_ctx, path);
+    if (lchown(buffer, credp->fc_uid, credp->fc_gid) < 0) {
+        /*
+         * If we fail to change ownership and if we are
+         * using security model none. Ignore the error
+         */
+        if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) {
+            goto err;
+        }
+    }
+
+    if (chmod(buffer, credp->fc_mode & 07777) < 0) {
+        goto err;
+    }
+
+    g_free(buffer);
+    return 0;
+err:
+    g_free(buffer);
+    return -1;
+}
+
+static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
+                              char *buf, size_t bufsz)
+{
+    ssize_t tsize = -1;
+    char *buffer;
+    char *path = fs_path->data;
+
+    if ((fs_ctx->export_flags & V9FS_SM_MAPPED) ||
+        (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE)) {
+        int fd;
+        buffer = rpath(fs_ctx, path);
+        fd = open(buffer, O_RDONLY | O_NOFOLLOW);
+        g_free(buffer);
+        if (fd == -1) {
+            return -1;
+        }
+        do {
+            tsize = read(fd, (void *)buf, bufsz);
+        } while (tsize == -1 && errno == EINTR);
+        close(fd);
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        tsize = readlink(buffer, buf, bufsz);
+        g_free(buffer);
+    }
+    return tsize;
+}
+
+static int local_close(FsContext *ctx, V9fsFidOpenState *fs)
+{
+    return close(fs->fd);
+}
+
+static int local_closedir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+    return closedir(fs->dir);
+}
+
+static int local_open(FsContext *ctx, V9fsPath *fs_path,
+                      int flags, V9fsFidOpenState *fs)
+{
+    char *buffer;
+    char *path = fs_path->data;
+
+    buffer = rpath(ctx, path);
+    fs->fd = open(buffer, flags | O_NOFOLLOW);
+    g_free(buffer);
+    return fs->fd;
+}
+
+static int local_opendir(FsContext *ctx,
+                         V9fsPath *fs_path, V9fsFidOpenState *fs)
+{
+    char *buffer;
+    char *path = fs_path->data;
+
+    buffer = rpath(ctx, path);
+    fs->dir = opendir(buffer);
+    g_free(buffer);
+    if (!fs->dir) {
+        return -1;
+    }
+    return 0;
+}
+
+static void local_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+    rewinddir(fs->dir);
+}
+
+static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+    return telldir(fs->dir);
+}
+
+static int local_readdir_r(FsContext *ctx, V9fsFidOpenState *fs,
+                           struct dirent *entry,
+                           struct dirent **result)
+{
+    int ret;
+
+again:
+    ret = readdir_r(fs->dir, entry, result);
+    if (ctx->export_flags & V9FS_SM_MAPPED) {
+        entry->d_type = DT_UNKNOWN;
+    } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        if (!ret && *result != NULL &&
+            !strcmp(entry->d_name, VIRTFS_META_DIR)) {
+            /* skp the meta data directory */
+            goto again;
+        }
+        entry->d_type = DT_UNKNOWN;
+    }
+    return ret;
+}
+
+static void local_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
+{
+    seekdir(fs->dir, off);
+}
+
+static ssize_t local_preadv(FsContext *ctx, V9fsFidOpenState *fs,
+                            const struct iovec *iov,
+                            int iovcnt, off_t offset)
+{
+#ifdef CONFIG_PREADV
+    return preadv(fs->fd, iov, iovcnt, offset);
+#else
+    int err = lseek(fs->fd, offset, SEEK_SET);
+    if (err == -1) {
+        return err;
+    } else {
+        return readv(fs->fd, iov, iovcnt);
+    }
+#endif
+}
+
+static ssize_t local_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
+                             const struct iovec *iov,
+                             int iovcnt, off_t offset)
+{
+    ssize_t ret
+;
+#ifdef CONFIG_PREADV
+    ret = pwritev(fs->fd, iov, iovcnt, offset);
+#else
+    int err = lseek(fs->fd, offset, SEEK_SET);
+    if (err == -1) {
+        return err;
+    } else {
+        ret = writev(fs->fd, iov, iovcnt);
+    }
+#endif
+#ifdef CONFIG_SYNC_FILE_RANGE
+    if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) {
+        /*
+         * Initiate a writeback. This is not a data integrity sync.
+         * We want to ensure that we don't leave dirty pages in the cache
+         * after write when writeout=immediate is sepcified.
+         */
+        sync_file_range(fs->fd, offset, ret,
+                        SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
+    }
+#endif
+    return ret;
+}
+
+static int local_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
+{
+    char *buffer;
+    int ret = -1;
+    char *path = fs_path->data;
+
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        buffer = rpath(fs_ctx, path);
+        ret = local_set_xattr(buffer, credp);
+        g_free(buffer);
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        return local_set_mapped_file_attr(fs_ctx, path, credp);
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        ret = chmod(buffer, credp->fc_mode);
+        g_free(buffer);
+    }
+    return ret;
+}
+
+static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
+                       const char *name, FsCred *credp)
+{
+    char *path;
+    int err = -1;
+    int serrno = 0;
+    V9fsString fullname;
+    char *buffer = NULL;
+
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
+    /* Determine the security model */
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        buffer = rpath(fs_ctx, path);
+        err = mknod(buffer, SM_LOCAL_MODE_BITS|S_IFREG, 0);
+        if (err == -1) {
+            goto out;
+        }
+        err = local_set_xattr(buffer, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+
+        buffer = rpath(fs_ctx, path);
+        err = mknod(buffer, SM_LOCAL_MODE_BITS|S_IFREG, 0);
+        if (err == -1) {
+            goto out;
+        }
+        err = local_set_mapped_file_attr(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        err = mknod(buffer, credp->fc_mode, credp->fc_rdev);
+        if (err == -1) {
+            goto out;
+        }
+        err = local_post_create_passthrough(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    }
+    goto out;
+
+err_end:
+    remove(buffer);
+    errno = serrno;
+out:
+    g_free(buffer);
+    v9fs_string_free(&fullname);
+    return err;
+}
+
+static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
+                       const char *name, FsCred *credp)
+{
+    char *path;
+    int err = -1;
+    int serrno = 0;
+    V9fsString fullname;
+    char *buffer = NULL;
+
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
+    /* Determine the security model */
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        buffer = rpath(fs_ctx, path);
+        err = mkdir(buffer, SM_LOCAL_DIR_MODE_BITS);
+        if (err == -1) {
+            goto out;
+        }
+        credp->fc_mode = credp->fc_mode|S_IFDIR;
+        err = local_set_xattr(buffer, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        buffer = rpath(fs_ctx, path);
+        err = mkdir(buffer, SM_LOCAL_DIR_MODE_BITS);
+        if (err == -1) {
+            goto out;
+        }
+        credp->fc_mode = credp->fc_mode|S_IFDIR;
+        err = local_set_mapped_file_attr(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        err = mkdir(buffer, credp->fc_mode);
+        if (err == -1) {
+            goto out;
+        }
+        err = local_post_create_passthrough(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    }
+    goto out;
+
+err_end:
+    remove(buffer);
+    errno = serrno;
+out:
+    g_free(buffer);
+    v9fs_string_free(&fullname);
+    return err;
+}
+
+static int local_fstat(FsContext *fs_ctx, int fid_type,
+                       V9fsFidOpenState *fs, struct stat *stbuf)
+{
+    int err, fd;
+
+    if (fid_type == P9_FID_DIR) {
+        fd = dirfd(fs->dir);
+    } else {
+        fd = fs->fd;
+    }
+
+    err = fstat(fd, stbuf);
+    if (err) {
+        return err;
+    }
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        /* Actual credentials are part of extended attrs */
+        uid_t tmp_uid;
+        gid_t tmp_gid;
+        mode_t tmp_mode;
+        dev_t tmp_dev;
+
+        if (fgetxattr(fd, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) {
+            stbuf->st_uid = le32_to_cpu(tmp_uid);
+        }
+        if (fgetxattr(fd, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) {
+            stbuf->st_gid = le32_to_cpu(tmp_gid);
+        }
+        if (fgetxattr(fd, "user.virtfs.mode", &tmp_mode, sizeof(mode_t)) > 0) {
+            stbuf->st_mode = le32_to_cpu(tmp_mode);
+        }
+        if (fgetxattr(fd, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) {
+            stbuf->st_rdev = le64_to_cpu(tmp_dev);
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        errno = EOPNOTSUPP;
+        return -1;
+    }
+    return err;
+}
+
+static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
+                       int flags, FsCred *credp, V9fsFidOpenState *fs)
+{
+    char *path;
+    int fd = -1;
+    int err = -1;
+    int serrno = 0;
+    V9fsString fullname;
+    char *buffer = NULL;
+
+    /*
+     * Mark all the open to not follow symlinks
+     */
+    flags |= O_NOFOLLOW;
+
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    path = fullname.data;
+
+    /* Determine the security model */
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        buffer = rpath(fs_ctx, path);
+        fd = open(buffer, flags, SM_LOCAL_MODE_BITS);
+        if (fd == -1) {
+            err = fd;
+            goto out;
+        }
+        credp->fc_mode = credp->fc_mode|S_IFREG;
+        /* Set cleint credentials in xattr */
+        err = local_set_xattr(buffer, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        buffer = rpath(fs_ctx, path);
+        fd = open(buffer, flags, SM_LOCAL_MODE_BITS);
+        if (fd == -1) {
+            err = fd;
+            goto out;
+        }
+        credp->fc_mode = credp->fc_mode|S_IFREG;
+        /* Set client credentials in .virtfs_metadata directory files */
+        err = local_set_mapped_file_attr(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        fd = open(buffer, flags, credp->fc_mode);
+        if (fd == -1) {
+            err = fd;
+            goto out;
+        }
+        err = local_post_create_passthrough(fs_ctx, path, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    }
+    err = fd;
+    fs->fd = fd;
+    goto out;
+
+err_end:
+    close(fd);
+    remove(buffer);
+    errno = serrno;
+out:
+    g_free(buffer);
+    v9fs_string_free(&fullname);
+    return err;
+}
+
+
+static int local_symlink(FsContext *fs_ctx, const char *oldpath,
+                         V9fsPath *dir_path, const char *name, FsCred *credp)
+{
+    int err = -1;
+    int serrno = 0;
+    char *newpath;
+    V9fsString fullname;
+    char *buffer = NULL;
+
+    v9fs_string_init(&fullname);
+    v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name);
+    newpath = fullname.data;
+
+    /* Determine the security model */
+    if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        int fd;
+        ssize_t oldpath_size, write_size;
+        buffer = rpath(fs_ctx, newpath);
+        fd = open(buffer, O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, SM_LOCAL_MODE_BITS);
+        if (fd == -1) {
+            err = fd;
+            goto out;
+        }
+        /* Write the oldpath (target) to the file. */
+        oldpath_size = strlen(oldpath);
+        do {
+            write_size = write(fd, (void *)oldpath, oldpath_size);
+        } while (write_size == -1 && errno == EINTR);
+
+        if (write_size != oldpath_size) {
+            serrno = errno;
+            close(fd);
+            err = -1;
+            goto err_end;
+        }
+        close(fd);
+        /* Set cleint credentials in symlink's xattr */
+        credp->fc_mode = credp->fc_mode|S_IFLNK;
+        err = local_set_xattr(buffer, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        int fd;
+        ssize_t oldpath_size, write_size;
+        buffer = rpath(fs_ctx, newpath);
+        fd = open(buffer, O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, SM_LOCAL_MODE_BITS);
+        if (fd == -1) {
+            err = fd;
+            goto out;
+        }
+        /* Write the oldpath (target) to the file. */
+        oldpath_size = strlen(oldpath);
+        do {
+            write_size = write(fd, (void *)oldpath, oldpath_size);
+        } while (write_size == -1 && errno == EINTR);
+
+        if (write_size != oldpath_size) {
+            serrno = errno;
+            close(fd);
+            err = -1;
+            goto err_end;
+        }
+        close(fd);
+        /* Set cleint credentials in symlink's xattr */
+        credp->fc_mode = credp->fc_mode|S_IFLNK;
+        err = local_set_mapped_file_attr(fs_ctx, newpath, credp);
+        if (err == -1) {
+            serrno = errno;
+            goto err_end;
+        }
+    } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+               (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, newpath);
+        err = symlink(oldpath, buffer);
+        if (err) {
+            goto out;
+        }
+        err = lchown(buffer, credp->fc_uid, credp->fc_gid);
+        if (err == -1) {
+            /*
+             * If we fail to change ownership and if we are
+             * using security model none. Ignore the error
+             */
+            if ((fs_ctx->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) {
+                serrno = errno;
+                goto err_end;
+            } else
+                err = 0;
+        }
+    }
+    goto out;
+
+err_end:
+    remove(buffer);
+    errno = serrno;
+out:
+    g_free(buffer);
+    v9fs_string_free(&fullname);
+    return err;
+}
+
+static int local_link(FsContext *ctx, V9fsPath *oldpath,
+                      V9fsPath *dirpath, const char *name)
+{
+    int ret;
+    V9fsString newpath;
+    char *buffer, *buffer1;
+
+    v9fs_string_init(&newpath);
+    v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name);
+
+    buffer = rpath(ctx, oldpath->data);
+    buffer1 = rpath(ctx, newpath.data);
+    ret = link(buffer, buffer1);
+    g_free(buffer);
+    g_free(buffer1);
+
+    /* now link the virtfs_metadata files */
+    if (!ret && (ctx->export_flags & V9FS_SM_MAPPED_FILE)) {
+        /* Link the .virtfs_metadata files. Create the metada directory */
+        ret = local_create_mapped_attr_dir(ctx, newpath.data);
+        if (ret < 0) {
+            goto err_out;
+        }
+        buffer = local_mapped_attr_path(ctx, oldpath->data);
+        buffer1 = local_mapped_attr_path(ctx, newpath.data);
+        ret = link(buffer, buffer1);
+        g_free(buffer);
+        g_free(buffer1);
+        if (ret < 0 && errno != ENOENT) {
+            goto err_out;
+        }
+    }
+err_out:
+    v9fs_string_free(&newpath);
+    return ret;
+}
+
+static int local_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
+{
+    char *buffer;
+    int ret;
+    char *path = fs_path->data;
+
+    buffer = rpath(ctx, path);
+    ret = truncate(buffer, size);
+    g_free(buffer);
+    return ret;
+}
+
+static int local_rename(FsContext *ctx, const char *oldpath,
+                        const char *newpath)
+{
+    int err;
+    char *buffer, *buffer1;
+
+    if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        err = local_create_mapped_attr_dir(ctx, newpath);
+        if (err < 0) {
+            return err;
+        }
+        /* rename the .virtfs_metadata files */
+        buffer = local_mapped_attr_path(ctx, oldpath);
+        buffer1 = local_mapped_attr_path(ctx, newpath);
+        err = rename(buffer, buffer1);
+        g_free(buffer);
+        g_free(buffer1);
+        if (err < 0 && errno != ENOENT) {
+            return err;
+        }
+    }
+
+    buffer = rpath(ctx, oldpath);
+    buffer1 = rpath(ctx, newpath);
+    err = rename(buffer, buffer1);
+    g_free(buffer);
+    g_free(buffer1);
+    return err;
+}
+
+static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
+{
+    char *buffer;
+    int ret = -1;
+    char *path = fs_path->data;
+
+    if ((credp->fc_uid == -1 && credp->fc_gid == -1) ||
+        (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+        (fs_ctx->export_flags & V9FS_SM_NONE)) {
+        buffer = rpath(fs_ctx, path);
+        ret = lchown(buffer, credp->fc_uid, credp->fc_gid);
+        g_free(buffer);
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+        buffer = rpath(fs_ctx, path);
+        ret = local_set_xattr(buffer, credp);
+        g_free(buffer);
+    } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        return local_set_mapped_file_attr(fs_ctx, path, credp);
+    }
+    return ret;
+}
+
+static int local_utimensat(FsContext *s, V9fsPath *fs_path,
+                           const struct timespec *buf)
+{
+    char *buffer;
+    int ret;
+    char *path = fs_path->data;
+
+    buffer = rpath(s, path);
+    ret = qemu_utimens(buffer, buf);
+    g_free(buffer);
+    return ret;
+}
+
+static int local_remove(FsContext *ctx, const char *path)
+{
+    int err;
+    struct stat stbuf;
+    char *buffer;
+
+    if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        buffer = rpath(ctx, path);
+        err =  lstat(buffer, &stbuf);
+        g_free(buffer);
+        if (err) {
+            goto err_out;
+        }
+        /*
+         * If directory remove .virtfs_metadata contained in the
+         * directory
+         */
+        if (S_ISDIR(stbuf.st_mode)) {
+            buffer = g_strdup_printf("%s/%s/%s", ctx->fs_root,
+                                     path, VIRTFS_META_DIR);
+            err = remove(buffer);
+            g_free(buffer);
+            if (err < 0 && errno != ENOENT) {
+                /*
+                 * We didn't had the .virtfs_metadata file. May be file created
+                 * in non-mapped mode ?. Ignore ENOENT.
+                 */
+                goto err_out;
+            }
+        }
+        /*
+         * Now remove the name from parent directory
+         * .virtfs_metadata directory
+         */
+        buffer = local_mapped_attr_path(ctx, path);
+        err = remove(buffer);
+        g_free(buffer);
+        if (err < 0 && errno != ENOENT) {
+            /*
+             * We didn't had the .virtfs_metadata file. May be file created
+             * in non-mapped mode ?. Ignore ENOENT.
+             */
+            goto err_out;
+        }
+    }
+
+    buffer = rpath(ctx, path);
+    err = remove(buffer);
+    g_free(buffer);
+err_out:
+    return err;
+}
+
+static int local_fsync(FsContext *ctx, int fid_type,
+                       V9fsFidOpenState *fs, int datasync)
+{
+    int fd;
+
+    if (fid_type == P9_FID_DIR) {
+        fd = dirfd(fs->dir);
+    } else {
+        fd = fs->fd;
+    }
+
+    if (datasync) {
+        return qemu_fdatasync(fd);
+    } else {
+        return fsync(fd);
+    }
+}
+
+static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf)
+{
+    char *buffer;
+    int ret;
+    char *path = fs_path->data;
+
+    buffer = rpath(s, path);
+    ret = statfs(buffer, stbuf);
+    g_free(buffer);
+    return ret;
+}
+
+static ssize_t local_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
+                               const char *name, void *value, size_t size)
+{
+    char *path = fs_path->data;
+
+    return v9fs_get_xattr(ctx, path, name, value, size);
+}
+
+static ssize_t local_llistxattr(FsContext *ctx, V9fsPath *fs_path,
+                                void *value, size_t size)
+{
+    char *path = fs_path->data;
+
+    return v9fs_list_xattr(ctx, path, value, size);
+}
+
+static int local_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
+                           void *value, size_t size, int flags)
+{
+    char *path = fs_path->data;
+
+    return v9fs_set_xattr(ctx, path, name, value, size, flags);
+}
+
+static int local_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
+                              const char *name)
+{
+    char *path = fs_path->data;
+
+    return v9fs_remove_xattr(ctx, path, name);
+}
+
+static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path,
+                              const char *name, V9fsPath *target)
+{
+    if (dir_path) {
+        v9fs_string_sprintf((V9fsString *)target, "%s/%s",
+                            dir_path->data, name);
+    } else {
+        v9fs_string_sprintf((V9fsString *)target, "%s", name);
+    }
+    /* Bump the size for including terminating NULL */
+    target->size++;
+    return 0;
+}
+
+static int local_renameat(FsContext *ctx, V9fsPath *olddir,
+                          const char *old_name, V9fsPath *newdir,
+                          const char *new_name)
+{
+    int ret;
+    V9fsString old_full_name, new_full_name;
+
+    v9fs_string_init(&old_full_name);
+    v9fs_string_init(&new_full_name);
+
+    v9fs_string_sprintf(&old_full_name, "%s/%s", olddir->data, old_name);
+    v9fs_string_sprintf(&new_full_name, "%s/%s", newdir->data, new_name);
+
+    ret = local_rename(ctx, old_full_name.data, new_full_name.data);
+    v9fs_string_free(&old_full_name);
+    v9fs_string_free(&new_full_name);
+    return ret;
+}
+
+static int local_unlinkat(FsContext *ctx, V9fsPath *dir,
+                          const char *name, int flags)
+{
+    int ret;
+    V9fsString fullname;
+    char *buffer;
+
+    v9fs_string_init(&fullname);
+
+    v9fs_string_sprintf(&fullname, "%s/%s", dir->data, name);
+    if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        if (flags == AT_REMOVEDIR) {
+            /*
+             * If directory remove .virtfs_metadata contained in the
+             * directory
+             */
+            buffer = g_strdup_printf("%s/%s/%s", ctx->fs_root,
+                                     fullname.data, VIRTFS_META_DIR);
+            ret = remove(buffer);
+            g_free(buffer);
+            if (ret < 0 && errno != ENOENT) {
+                /*
+                 * We didn't had the .virtfs_metadata file. May be file created
+                 * in non-mapped mode ?. Ignore ENOENT.
+                 */
+                goto err_out;
+            }
+        }
+        /*
+         * Now remove the name from parent directory
+         * .virtfs_metadata directory.
+         */
+        buffer = local_mapped_attr_path(ctx, fullname.data);
+        ret = remove(buffer);
+        g_free(buffer);
+        if (ret < 0 && errno != ENOENT) {
+            /*
+             * We didn't had the .virtfs_metadata file. May be file created
+             * in non-mapped mode ?. Ignore ENOENT.
+             */
+            goto err_out;
+        }
+    }
+    /* Remove the name finally */
+    buffer = rpath(ctx, fullname.data);
+    ret = remove(buffer);
+    g_free(buffer);
+
+err_out:
+    v9fs_string_free(&fullname);
+    return ret;
+}
+
+static int local_ioc_getversion(FsContext *ctx, V9fsPath *path,
+                                mode_t st_mode, uint64_t *st_gen)
+{
+#ifdef FS_IOC_GETVERSION
+    int err;
+    V9fsFidOpenState fid_open;
+
+    /*
+     * Do not try to open special files like device nodes, fifos etc
+     * We can get fd for regular files and directories only
+     */
+    if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
+        errno = ENOTTY;
+        return -1;
+    }
+    err = local_open(ctx, path, O_RDONLY, &fid_open);
+    if (err < 0) {
+        return err;
+    }
+    err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
+    local_close(ctx, &fid_open);
+    return err;
+#else
+    errno = ENOTTY;
+    return -1;
+#endif
+}
+
+static int local_init(FsContext *ctx)
+{
+    int err = 0;
+    struct statfs stbuf;
+
+    if (ctx->export_flags & V9FS_SM_PASSTHROUGH) {
+        ctx->xops = passthrough_xattr_ops;
+    } else if (ctx->export_flags & V9FS_SM_MAPPED) {
+        ctx->xops = mapped_xattr_ops;
+    } else if (ctx->export_flags & V9FS_SM_NONE) {
+        ctx->xops = none_xattr_ops;
+    } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+        /*
+         * xattr operation for mapped-file and passthrough
+         * remain same.
+         */
+        ctx->xops = passthrough_xattr_ops;
+    }
+    ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT;
+#ifdef FS_IOC_GETVERSION
+    /*
+     * use ioc_getversion only if the iocl is definied
+     */
+    err = statfs(ctx->fs_root, &stbuf);
+    if (!err) {
+        switch (stbuf.f_type) {
+        case EXT2_SUPER_MAGIC:
+        case BTRFS_SUPER_MAGIC:
+        case REISERFS_SUPER_MAGIC:
+        case XFS_SUPER_MAGIC:
+            ctx->exops.get_st_gen = local_ioc_getversion;
+            break;
+        }
+    }
+#endif
+    return err;
+}
+
+static int local_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse)
+{
+    const char *sec_model = qemu_opt_get(opts, "security_model");
+    const char *path = qemu_opt_get(opts, "path");
+
+    if (!sec_model) {
+        fprintf(stderr, "security model not specified, "
+                "local fs needs security model\nvalid options are:"
+                "\tsecurity_model=[passthrough|mapped|none]\n");
+        return -1;
+    }
+
+    if (!strcmp(sec_model, "passthrough")) {
+        fse->export_flags |= V9FS_SM_PASSTHROUGH;
+    } else if (!strcmp(sec_model, "mapped") ||
+               !strcmp(sec_model, "mapped-xattr")) {
+        fse->export_flags |= V9FS_SM_MAPPED;
+    } else if (!strcmp(sec_model, "none")) {
+        fse->export_flags |= V9FS_SM_NONE;
+    } else if (!strcmp(sec_model, "mapped-file")) {
+        fse->export_flags |= V9FS_SM_MAPPED_FILE;
+    } else {
+        fprintf(stderr, "Invalid security model %s specified, valid options are"
+                "\n\t [passthrough|mapped-xattr|mapped-file|none]\n",
+                sec_model);
+        return -1;
+    }
+
+    if (!path) {
+        fprintf(stderr, "fsdev: No path specified.\n");
+        return -1;
+    }
+    fse->path = g_strdup(path);
+
+    return 0;
+}
+
+FileOperations local_ops = {
+    .parse_opts = local_parse_opts,
+    .init  = local_init,
+    .lstat = local_lstat,
+    .readlink = local_readlink,
+    .close = local_close,
+    .closedir = local_closedir,
+    .open = local_open,
+    .opendir = local_opendir,
+    .rewinddir = local_rewinddir,
+    .telldir = local_telldir,
+    .readdir_r = local_readdir_r,
+    .seekdir = local_seekdir,
+    .preadv = local_preadv,
+    .pwritev = local_pwritev,
+    .chmod = local_chmod,
+    .mknod = local_mknod,
+    .mkdir = local_mkdir,
+    .fstat = local_fstat,
+    .open2 = local_open2,
+    .symlink = local_symlink,
+    .link = local_link,
+    .truncate = local_truncate,
+    .rename = local_rename,
+    .chown = local_chown,
+    .utimensat = local_utimensat,
+    .remove = local_remove,
+    .fsync = local_fsync,
+    .statfs = local_statfs,
+    .lgetxattr = local_lgetxattr,
+    .llistxattr = local_llistxattr,
+    .lsetxattr = local_lsetxattr,
+    .lremovexattr = local_lremovexattr,
+    .name_to_path = local_name_to_path,
+    .renameat  = local_renameat,
+    .unlinkat = local_unlinkat,
+};