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authorTimos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>2023-10-10 11:40:56 +0000
committerTimos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>2023-10-10 11:40:56 +0000
commite02cda008591317b1625707ff8e115a4841aa889 (patch)
treeaee302e3cf8b59ec2d32ec481be3d1afddfc8968 /hw/9pfs/9p-local.c
parentcc668e6b7e0ffd8c9d130513d12053cf5eda1d3b (diff)
Introduce Virtio-loopback epsilon release:
Epsilon release introduces a new compatibility layer which make virtio-loopback design to work with QEMU and rust-vmm vhost-user backend without require any changes. Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com> Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9
Diffstat (limited to 'hw/9pfs/9p-local.c')
-rw-r--r--hw/9pfs/9p-local.c1601
1 files changed, 1601 insertions, 0 deletions
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c
new file mode 100644
index 000000000..210d9e770
--- /dev/null
+++ b/hw/9pfs/9p-local.c
@@ -0,0 +1,1601 @@
+/*
+ * 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.
+ */
+
+/*
+ * Not so fast! You might want to read the 9p developer docs first:
+ * https://wiki.qemu.org/Documentation/9p
+ */
+
+#include "qemu/osdep.h"
+#include "9p.h"
+#include "9p-local.h"
+#include "9p-xattr.h"
+#include "9p-util.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 "qapi/error.h"
+#include "qemu/cutils.h"
+#include "qemu/error-report.h"
+#include "qemu/option.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
+
+typedef struct {
+ int mountfd;
+} LocalData;
+
+int local_open_nofollow(FsContext *fs_ctx, const char *path, int flags,
+ mode_t mode)
+{
+ LocalData *data = fs_ctx->private;
+ int fd = data->mountfd;
+
+ while (*path && fd != -1) {
+ const char *c;
+ int next_fd;
+ char *head;
+
+ /* Only relative paths without consecutive slashes */
+ assert(*path != '/');
+
+ head = g_strdup(path);
+ c = qemu_strchrnul(path, '/');
+ if (*c) {
+ /* Intermediate path element */
+ head[c - path] = 0;
+ path = c + 1;
+ next_fd = openat_dir(fd, head);
+ } else {
+ /* Rightmost path element */
+ next_fd = openat_file(fd, head, flags, mode);
+ path = c;
+ }
+ g_free(head);
+ if (fd != data->mountfd) {
+ close_preserve_errno(fd);
+ }
+ fd = next_fd;
+ }
+
+ assert(fd != data->mountfd);
+ return fd;
+}
+
+int local_opendir_nofollow(FsContext *fs_ctx, const char *path)
+{
+ return local_open_nofollow(fs_ctx, path, O_DIRECTORY | O_RDONLY, 0);
+}
+
+static void renameat_preserve_errno(int odirfd, const char *opath, int ndirfd,
+ const char *npath)
+{
+ int serrno = errno;
+ renameat(odirfd, opath, ndirfd, npath);
+ errno = serrno;
+}
+
+static void unlinkat_preserve_errno(int dirfd, const char *path, int flags)
+{
+ int serrno = errno;
+ unlinkat(dirfd, path, flags);
+ errno = serrno;
+}
+
+#define VIRTFS_META_DIR ".virtfs_metadata"
+#define VIRTFS_META_ROOT_FILE VIRTFS_META_DIR "_root"
+
+static FILE *local_fopenat(int dirfd, const char *name, const char *mode)
+{
+ int fd, o_mode = 0;
+ FILE *fp;
+ int flags;
+ /*
+ * 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 = openat_file(dirfd, name, 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(int dirfd, const char *name,
+ struct stat *stbuf)
+{
+ FILE *fp;
+ char buf[ATTR_MAX];
+ int map_dirfd;
+
+ if (strcmp(name, ".")) {
+ map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
+ if (map_dirfd == -1) {
+ return;
+ }
+
+ fp = local_fopenat(map_dirfd, name, "r");
+ close_preserve_errno(map_dirfd);
+ } else {
+ fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");
+ }
+ 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 = -1;
+ char *dirpath = g_path_get_dirname(fs_path->data);
+ char *name = g_path_get_basename(fs_path->data);
+ int dirfd;
+
+ dirfd = local_opendir_nofollow(fs_ctx, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ err = fstatat(dirfd, name, stbuf, AT_SYMLINK_NOFOLLOW);
+ 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 (fgetxattrat_nofollow(dirfd, name, "user.virtfs.uid", &tmp_uid,
+ sizeof(uid_t)) > 0) {
+ stbuf->st_uid = le32_to_cpu(tmp_uid);
+ }
+ if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.gid", &tmp_gid,
+ sizeof(gid_t)) > 0) {
+ stbuf->st_gid = le32_to_cpu(tmp_gid);
+ }
+ if (fgetxattrat_nofollow(dirfd, name, "user.virtfs.mode", &tmp_mode,
+ sizeof(mode_t)) > 0) {
+ stbuf->st_mode = le32_to_cpu(tmp_mode);
+ }
+ if (fgetxattrat_nofollow(dirfd, name, "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(dirfd, name, stbuf);
+ }
+
+err_out:
+ close_preserve_errno(dirfd);
+out:
+ g_free(name);
+ g_free(dirpath);
+ return err;
+}
+
+static int local_set_mapped_file_attrat(int dirfd, const char *name,
+ FsCred *credp)
+{
+ FILE *fp;
+ int ret;
+ char buf[ATTR_MAX];
+ int uid = -1, gid = -1, mode = -1, rdev = -1;
+ int map_dirfd = -1, map_fd;
+ bool is_root = !strcmp(name, ".");
+
+ if (is_root) {
+ fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "r");
+ if (!fp) {
+ if (errno == ENOENT) {
+ goto update_map_file;
+ } else {
+ return -1;
+ }
+ }
+ } else {
+ ret = mkdirat(dirfd, VIRTFS_META_DIR, 0700);
+ if (ret < 0 && errno != EEXIST) {
+ return -1;
+ }
+
+ map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
+ if (map_dirfd == -1) {
+ return -1;
+ }
+
+ fp = local_fopenat(map_dirfd, name, "r");
+ if (!fp) {
+ if (errno == ENOENT) {
+ goto update_map_file;
+ } else {
+ close_preserve_errno(map_dirfd);
+ return -1;
+ }
+ }
+ }
+ 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);
+
+update_map_file:
+ if (is_root) {
+ fp = local_fopenat(dirfd, VIRTFS_META_ROOT_FILE, "w");
+ } else {
+ fp = local_fopenat(map_dirfd, name, "w");
+ /* We can't go this far with map_dirfd not being a valid file descriptor
+ * but some versions of gcc aren't smart enough to see it.
+ */
+ if (map_dirfd != -1) {
+ close_preserve_errno(map_dirfd);
+ }
+ }
+ if (!fp) {
+ return -1;
+ }
+
+ map_fd = fileno(fp);
+ assert(map_fd != -1);
+ ret = fchmod(map_fd, 0600);
+ assert(ret == 0);
+
+ if (credp->fc_uid != -1) {
+ uid = credp->fc_uid;
+ }
+ if (credp->fc_gid != -1) {
+ gid = credp->fc_gid;
+ }
+ if (credp->fc_mode != (mode_t)-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);
+
+ return 0;
+}
+
+static int fchmodat_nofollow(int dirfd, const char *name, mode_t mode)
+{
+ struct stat stbuf;
+ int fd, ret;
+
+ /* FIXME: this should be handled with fchmodat(AT_SYMLINK_NOFOLLOW).
+ * Unfortunately, the linux kernel doesn't implement it yet.
+ */
+
+ /* First, we clear non-racing symlinks out of the way. */
+ if (fstatat(dirfd, name, &stbuf, AT_SYMLINK_NOFOLLOW)) {
+ return -1;
+ }
+ if (S_ISLNK(stbuf.st_mode)) {
+ errno = ELOOP;
+ return -1;
+ }
+
+ fd = openat_file(dirfd, name, O_RDONLY | O_PATH_9P_UTIL | O_NOFOLLOW, 0);
+#if O_PATH_9P_UTIL == 0
+ /* Fallback for systems that don't support O_PATH: we depend on the file
+ * being readable or writable.
+ */
+ if (fd == -1) {
+ /* In case the file is writable-only and isn't a directory. */
+ if (errno == EACCES) {
+ fd = openat_file(dirfd, name, O_WRONLY, 0);
+ }
+ if (fd == -1 && errno == EISDIR) {
+ errno = EACCES;
+ }
+ }
+ if (fd == -1) {
+ return -1;
+ }
+ ret = fchmod(fd, mode);
+#else
+ /* Access modes are ignored when O_PATH is supported. If name is a symbolic
+ * link, O_PATH | O_NOFOLLOW causes openat(2) to return a file descriptor
+ * referring to the symbolic link.
+ */
+ if (fd == -1) {
+ return -1;
+ }
+
+ /* Now we handle racing symlinks. */
+ ret = fstat(fd, &stbuf);
+ if (!ret) {
+ if (S_ISLNK(stbuf.st_mode)) {
+ errno = ELOOP;
+ ret = -1;
+ } else {
+ char *proc_path = g_strdup_printf("/proc/self/fd/%d", fd);
+ ret = chmod(proc_path, mode);
+ g_free(proc_path);
+ }
+ }
+#endif
+ close_preserve_errno(fd);
+ return ret;
+}
+
+static int local_set_xattrat(int dirfd, const char *path, FsCred *credp)
+{
+ int err;
+
+ if (credp->fc_uid != -1) {
+ uint32_t tmp_uid = cpu_to_le32(credp->fc_uid);
+ err = fsetxattrat_nofollow(dirfd, 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 = fsetxattrat_nofollow(dirfd, path, "user.virtfs.gid", &tmp_gid,
+ sizeof(gid_t), 0);
+ if (err) {
+ return err;
+ }
+ }
+ if (credp->fc_mode != (mode_t)-1) {
+ uint32_t tmp_mode = cpu_to_le32(credp->fc_mode);
+ err = fsetxattrat_nofollow(dirfd, 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 = fsetxattrat_nofollow(dirfd, path, "user.virtfs.rdev", &tmp_rdev,
+ sizeof(dev_t), 0);
+ if (err) {
+ return err;
+ }
+ }
+ return 0;
+}
+
+static int local_set_cred_passthrough(FsContext *fs_ctx, int dirfd,
+ const char *name, FsCred *credp)
+{
+ if (fchownat(dirfd, name, credp->fc_uid, credp->fc_gid,
+ AT_SYMLINK_NOFOLLOW) < 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) {
+ return -1;
+ }
+ }
+
+ return fchmodat_nofollow(dirfd, name, credp->fc_mode & 07777);
+}
+
+static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
+ char *buf, size_t bufsz)
+{
+ ssize_t tsize = -1;
+
+ if ((fs_ctx->export_flags & V9FS_SM_MAPPED) ||
+ (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE)) {
+ int fd;
+
+ fd = local_open_nofollow(fs_ctx, fs_path->data, O_RDONLY, 0);
+ if (fd == -1) {
+ return -1;
+ }
+ do {
+ tsize = read(fd, (void *)buf, bufsz);
+ } while (tsize == -1 && errno == EINTR);
+ close_preserve_errno(fd);
+ } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+ (fs_ctx->export_flags & V9FS_SM_NONE)) {
+ char *dirpath = g_path_get_dirname(fs_path->data);
+ char *name = g_path_get_basename(fs_path->data);
+ int dirfd;
+
+ dirfd = local_opendir_nofollow(fs_ctx, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ tsize = readlinkat(dirfd, name, buf, bufsz);
+ close_preserve_errno(dirfd);
+ out:
+ g_free(name);
+ g_free(dirpath);
+ }
+ 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.stream);
+}
+
+static int local_open(FsContext *ctx, V9fsPath *fs_path,
+ int flags, V9fsFidOpenState *fs)
+{
+ int fd;
+
+ fd = local_open_nofollow(ctx, fs_path->data, flags, 0);
+ if (fd == -1) {
+ return -1;
+ }
+ fs->fd = fd;
+ return fs->fd;
+}
+
+static int local_opendir(FsContext *ctx,
+ V9fsPath *fs_path, V9fsFidOpenState *fs)
+{
+ int dirfd;
+ DIR *stream;
+
+ dirfd = local_opendir_nofollow(ctx, fs_path->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ stream = fdopendir(dirfd);
+ if (!stream) {
+ close(dirfd);
+ return -1;
+ }
+ fs->dir.stream = stream;
+ return 0;
+}
+
+static void local_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+ rewinddir(fs->dir.stream);
+}
+
+static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+ return telldir(fs->dir.stream);
+}
+
+static bool local_is_mapped_file_metadata(FsContext *fs_ctx, const char *name)
+{
+ return
+ !strcmp(name, VIRTFS_META_DIR) || !strcmp(name, VIRTFS_META_ROOT_FILE);
+}
+
+static struct dirent *local_readdir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+ struct dirent *entry;
+
+again:
+ entry = readdir(fs->dir.stream);
+ if (!entry) {
+ return NULL;
+ }
+
+ if (ctx->export_flags & V9FS_SM_MAPPED) {
+ entry->d_type = DT_UNKNOWN;
+ } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ if (local_is_mapped_file_metadata(ctx, entry->d_name)) {
+ /* skip the meta data */
+ goto again;
+ }
+ entry->d_type = DT_UNKNOWN;
+ }
+
+ return entry;
+}
+
+static void local_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
+{
+ seekdir(fs->dir.stream, 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 *dirpath = g_path_get_dirname(fs_path->data);
+ char *name = g_path_get_basename(fs_path->data);
+ int ret = -1;
+ int dirfd;
+
+ dirfd = local_opendir_nofollow(fs_ctx, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ ret = local_set_xattrat(dirfd, name, credp);
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ ret = local_set_mapped_file_attrat(dirfd, name, credp);
+ } else if (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH ||
+ fs_ctx->export_flags & V9FS_SM_NONE) {
+ ret = fchmodat_nofollow(dirfd, name, credp->fc_mode);
+ }
+ close_preserve_errno(dirfd);
+
+out:
+ g_free(dirpath);
+ g_free(name);
+ return ret;
+}
+
+static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
+ const char *name, FsCred *credp)
+{
+ int err = -1;
+ int dirfd;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(fs_ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ dirfd = local_opendir_nofollow(fs_ctx, dir_path->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED ||
+ fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ err = mknodat(dirfd, name, fs_ctx->fmode | S_IFREG, 0);
+ if (err == -1) {
+ goto out;
+ }
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ err = local_set_xattrat(dirfd, name, credp);
+ } else {
+ err = local_set_mapped_file_attrat(dirfd, name, credp);
+ }
+ if (err == -1) {
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH ||
+ fs_ctx->export_flags & V9FS_SM_NONE) {
+ err = mknodat(dirfd, name, credp->fc_mode, credp->fc_rdev);
+ if (err == -1) {
+ goto out;
+ }
+ err = local_set_cred_passthrough(fs_ctx, dirfd, name, credp);
+ if (err == -1) {
+ goto err_end;
+ }
+ }
+ goto out;
+
+err_end:
+ unlinkat_preserve_errno(dirfd, name, 0);
+out:
+ close_preserve_errno(dirfd);
+ return err;
+}
+
+static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
+ const char *name, FsCred *credp)
+{
+ int err = -1;
+ int dirfd;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(fs_ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ dirfd = local_opendir_nofollow(fs_ctx, dir_path->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED ||
+ fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ err = mkdirat(dirfd, name, fs_ctx->dmode);
+ if (err == -1) {
+ goto out;
+ }
+ credp->fc_mode = credp->fc_mode | S_IFDIR;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ err = local_set_xattrat(dirfd, name, credp);
+ } else {
+ err = local_set_mapped_file_attrat(dirfd, name, credp);
+ }
+ if (err == -1) {
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH ||
+ fs_ctx->export_flags & V9FS_SM_NONE) {
+ err = mkdirat(dirfd, name, credp->fc_mode);
+ if (err == -1) {
+ goto out;
+ }
+ err = local_set_cred_passthrough(fs_ctx, dirfd, name, credp);
+ if (err == -1) {
+ goto err_end;
+ }
+ }
+ goto out;
+
+err_end:
+ unlinkat_preserve_errno(dirfd, name, AT_REMOVEDIR);
+out:
+ close_preserve_errno(dirfd);
+ 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.stream);
+ } 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)
+{
+ int fd = -1;
+ int err = -1;
+ int dirfd;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(fs_ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ /*
+ * Mark all the open to not follow symlinks
+ */
+ flags |= O_NOFOLLOW;
+
+ dirfd = local_opendir_nofollow(fs_ctx, dir_path->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ /* Determine the security model */
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED ||
+ fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ fd = openat_file(dirfd, name, flags, fs_ctx->fmode);
+ if (fd == -1) {
+ goto out;
+ }
+ credp->fc_mode = credp->fc_mode | S_IFREG;
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ /* Set cleint credentials in xattr */
+ err = local_set_xattrat(dirfd, name, credp);
+ } else {
+ err = local_set_mapped_file_attrat(dirfd, name, credp);
+ }
+ if (err == -1) {
+ goto err_end;
+ }
+ } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+ (fs_ctx->export_flags & V9FS_SM_NONE)) {
+ fd = openat_file(dirfd, name, flags, credp->fc_mode);
+ if (fd == -1) {
+ goto out;
+ }
+ err = local_set_cred_passthrough(fs_ctx, dirfd, name, credp);
+ if (err == -1) {
+ goto err_end;
+ }
+ }
+ err = fd;
+ fs->fd = fd;
+ goto out;
+
+err_end:
+ unlinkat_preserve_errno(dirfd, name,
+ flags & O_DIRECTORY ? AT_REMOVEDIR : 0);
+ close_preserve_errno(fd);
+out:
+ close_preserve_errno(dirfd);
+ return err;
+}
+
+
+static int local_symlink(FsContext *fs_ctx, const char *oldpath,
+ V9fsPath *dir_path, const char *name, FsCred *credp)
+{
+ int err = -1;
+ int dirfd;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(fs_ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ dirfd = local_opendir_nofollow(fs_ctx, dir_path->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ /* Determine the security model */
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED ||
+ fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ int fd;
+ ssize_t oldpath_size, write_size;
+
+ fd = openat_file(dirfd, name, O_CREAT | O_EXCL | O_RDWR,
+ fs_ctx->fmode);
+ if (fd == -1) {
+ 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);
+ close_preserve_errno(fd);
+
+ if (write_size != oldpath_size) {
+ goto err_end;
+ }
+ /* Set cleint credentials in symlink's xattr */
+ credp->fc_mode = credp->fc_mode | S_IFLNK;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ err = local_set_xattrat(dirfd, name, credp);
+ } else {
+ err = local_set_mapped_file_attrat(dirfd, name, credp);
+ }
+ if (err == -1) {
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH ||
+ fs_ctx->export_flags & V9FS_SM_NONE) {
+ err = symlinkat(oldpath, dirfd, name);
+ if (err) {
+ goto out;
+ }
+ err = fchownat(dirfd, name, credp->fc_uid, credp->fc_gid,
+ AT_SYMLINK_NOFOLLOW);
+ 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) {
+ goto err_end;
+ } else {
+ err = 0;
+ }
+ }
+ }
+ goto out;
+
+err_end:
+ unlinkat_preserve_errno(dirfd, name, 0);
+out:
+ close_preserve_errno(dirfd);
+ return err;
+}
+
+static int local_link(FsContext *ctx, V9fsPath *oldpath,
+ V9fsPath *dirpath, const char *name)
+{
+ char *odirpath = g_path_get_dirname(oldpath->data);
+ char *oname = g_path_get_basename(oldpath->data);
+ int ret = -1;
+ int odirfd, ndirfd;
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(ctx, name)) {
+ errno = EINVAL;
+ goto out;
+ }
+
+ odirfd = local_opendir_nofollow(ctx, odirpath);
+ if (odirfd == -1) {
+ goto out;
+ }
+
+ ndirfd = local_opendir_nofollow(ctx, dirpath->data);
+ if (ndirfd == -1) {
+ close_preserve_errno(odirfd);
+ goto out;
+ }
+
+ ret = linkat(odirfd, oname, ndirfd, name, 0);
+ if (ret < 0) {
+ goto out_close;
+ }
+
+ /* now link the virtfs_metadata files */
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ int omap_dirfd, nmap_dirfd;
+
+ ret = mkdirat(ndirfd, VIRTFS_META_DIR, 0700);
+ if (ret < 0 && errno != EEXIST) {
+ goto err_undo_link;
+ }
+
+ omap_dirfd = openat_dir(odirfd, VIRTFS_META_DIR);
+ if (omap_dirfd == -1) {
+ goto err;
+ }
+
+ nmap_dirfd = openat_dir(ndirfd, VIRTFS_META_DIR);
+ if (nmap_dirfd == -1) {
+ close_preserve_errno(omap_dirfd);
+ goto err;
+ }
+
+ ret = linkat(omap_dirfd, oname, nmap_dirfd, name, 0);
+ close_preserve_errno(nmap_dirfd);
+ close_preserve_errno(omap_dirfd);
+ if (ret < 0 && errno != ENOENT) {
+ goto err_undo_link;
+ }
+
+ ret = 0;
+ }
+ goto out_close;
+
+err:
+ ret = -1;
+err_undo_link:
+ unlinkat_preserve_errno(ndirfd, name, 0);
+out_close:
+ close_preserve_errno(ndirfd);
+ close_preserve_errno(odirfd);
+out:
+ g_free(oname);
+ g_free(odirpath);
+ return ret;
+}
+
+static int local_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
+{
+ int fd, ret;
+
+ fd = local_open_nofollow(ctx, fs_path->data, O_WRONLY, 0);
+ if (fd == -1) {
+ return -1;
+ }
+ ret = ftruncate(fd, size);
+ close_preserve_errno(fd);
+ return ret;
+}
+
+static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
+{
+ char *dirpath = g_path_get_dirname(fs_path->data);
+ char *name = g_path_get_basename(fs_path->data);
+ int ret = -1;
+ int dirfd;
+
+ dirfd = local_opendir_nofollow(fs_ctx, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ if ((credp->fc_uid == -1 && credp->fc_gid == -1) ||
+ (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+ (fs_ctx->export_flags & V9FS_SM_NONE)) {
+ ret = fchownat(dirfd, name, credp->fc_uid, credp->fc_gid,
+ AT_SYMLINK_NOFOLLOW);
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ ret = local_set_xattrat(dirfd, name, credp);
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ ret = local_set_mapped_file_attrat(dirfd, name, credp);
+ }
+
+ close_preserve_errno(dirfd);
+out:
+ g_free(name);
+ g_free(dirpath);
+ return ret;
+}
+
+static int local_utimensat(FsContext *s, V9fsPath *fs_path,
+ const struct timespec *buf)
+{
+ char *dirpath = g_path_get_dirname(fs_path->data);
+ char *name = g_path_get_basename(fs_path->data);
+ int dirfd, ret = -1;
+
+ dirfd = local_opendir_nofollow(s, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ ret = utimensat(dirfd, name, buf, AT_SYMLINK_NOFOLLOW);
+ close_preserve_errno(dirfd);
+out:
+ g_free(dirpath);
+ g_free(name);
+ return ret;
+}
+
+static int local_unlinkat_common(FsContext *ctx, int dirfd, const char *name,
+ int flags)
+{
+ int ret;
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ int map_dirfd;
+
+ /* We need to remove the metadata as well:
+ * - the metadata directory if we're removing a directory
+ * - the metadata file in the parent's metadata directory
+ *
+ * If any of these are missing (ie, ENOENT) then we're probably
+ * trying to remove something that wasn't created in mapped-file
+ * mode. We just ignore the error.
+ */
+ if (flags == AT_REMOVEDIR) {
+ int fd;
+
+ fd = openat_dir(dirfd, name);
+ if (fd == -1) {
+ return -1;
+ }
+ ret = unlinkat(fd, VIRTFS_META_DIR, AT_REMOVEDIR);
+ close_preserve_errno(fd);
+ if (ret < 0 && errno != ENOENT) {
+ return -1;
+ }
+ }
+ map_dirfd = openat_dir(dirfd, VIRTFS_META_DIR);
+ if (map_dirfd != -1) {
+ ret = unlinkat(map_dirfd, name, 0);
+ close_preserve_errno(map_dirfd);
+ if (ret < 0 && errno != ENOENT) {
+ return -1;
+ }
+ } else if (errno != ENOENT) {
+ return -1;
+ }
+ }
+
+ return unlinkat(dirfd, name, flags);
+}
+
+static int local_remove(FsContext *ctx, const char *path)
+{
+ struct stat stbuf;
+ char *dirpath = g_path_get_dirname(path);
+ char *name = g_path_get_basename(path);
+ int flags = 0;
+ int dirfd;
+ int err = -1;
+
+ dirfd = local_opendir_nofollow(ctx, dirpath);
+ if (dirfd == -1) {
+ goto out;
+ }
+
+ if (fstatat(dirfd, name, &stbuf, AT_SYMLINK_NOFOLLOW) < 0) {
+ goto err_out;
+ }
+
+ if (S_ISDIR(stbuf.st_mode)) {
+ flags |= AT_REMOVEDIR;
+ }
+
+ err = local_unlinkat_common(ctx, dirfd, name, flags);
+err_out:
+ close_preserve_errno(dirfd);
+out:
+ g_free(name);
+ g_free(dirpath);
+ 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.stream);
+ } 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)
+{
+ int fd, ret;
+
+ fd = local_open_nofollow(s, fs_path->data, O_RDONLY, 0);
+ if (fd == -1) {
+ return -1;
+ }
+ ret = fstatfs(fd, stbuf);
+ close_preserve_errno(fd);
+ 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 (ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (dir_path) {
+ if (!strcmp(name, ".")) {
+ /* "." relative to "foo/bar" is "foo/bar" */
+ v9fs_path_copy(target, dir_path);
+ } else if (!strcmp(name, "..")) {
+ if (!strcmp(dir_path->data, ".")) {
+ /* ".." relative to the root is "." */
+ v9fs_path_sprintf(target, ".");
+ } else {
+ char *tmp = g_path_get_dirname(dir_path->data);
+ /* Symbolic links are resolved by the client. We can assume
+ * that ".." relative to "foo/bar" is equivalent to "foo"
+ */
+ v9fs_path_sprintf(target, "%s", tmp);
+ g_free(tmp);
+ }
+ } else {
+ assert(!strchr(name, '/'));
+ v9fs_path_sprintf(target, "%s/%s", dir_path->data, name);
+ }
+ } else if (!strcmp(name, "/") || !strcmp(name, ".") ||
+ !strcmp(name, "..")) {
+ /* This is the root fid */
+ v9fs_path_sprintf(target, ".");
+ } else {
+ assert(!strchr(name, '/'));
+ v9fs_path_sprintf(target, "./%s", name);
+ }
+ return 0;
+}
+
+static int local_renameat(FsContext *ctx, V9fsPath *olddir,
+ const char *old_name, V9fsPath *newdir,
+ const char *new_name)
+{
+ int ret;
+ int odirfd, ndirfd;
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ (local_is_mapped_file_metadata(ctx, old_name) ||
+ local_is_mapped_file_metadata(ctx, new_name))) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ odirfd = local_opendir_nofollow(ctx, olddir->data);
+ if (odirfd == -1) {
+ return -1;
+ }
+
+ ndirfd = local_opendir_nofollow(ctx, newdir->data);
+ if (ndirfd == -1) {
+ close_preserve_errno(odirfd);
+ return -1;
+ }
+
+ ret = renameat(odirfd, old_name, ndirfd, new_name);
+ if (ret < 0) {
+ goto out;
+ }
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ int omap_dirfd, nmap_dirfd;
+
+ ret = mkdirat(ndirfd, VIRTFS_META_DIR, 0700);
+ if (ret < 0 && errno != EEXIST) {
+ goto err_undo_rename;
+ }
+
+ omap_dirfd = openat_dir(odirfd, VIRTFS_META_DIR);
+ if (omap_dirfd == -1) {
+ goto err;
+ }
+
+ nmap_dirfd = openat_dir(ndirfd, VIRTFS_META_DIR);
+ if (nmap_dirfd == -1) {
+ close_preserve_errno(omap_dirfd);
+ goto err;
+ }
+
+ /* rename the .virtfs_metadata files */
+ ret = renameat(omap_dirfd, old_name, nmap_dirfd, new_name);
+ close_preserve_errno(nmap_dirfd);
+ close_preserve_errno(omap_dirfd);
+ if (ret < 0 && errno != ENOENT) {
+ goto err_undo_rename;
+ }
+
+ ret = 0;
+ }
+ goto out;
+
+err:
+ ret = -1;
+err_undo_rename:
+ renameat_preserve_errno(ndirfd, new_name, odirfd, old_name);
+out:
+ close_preserve_errno(ndirfd);
+ close_preserve_errno(odirfd);
+ return ret;
+}
+
+static void v9fs_path_init_dirname(V9fsPath *path, const char *str)
+{
+ path->data = g_path_get_dirname(str);
+ path->size = strlen(path->data) + 1;
+}
+
+static int local_rename(FsContext *ctx, const char *oldpath,
+ const char *newpath)
+{
+ int err;
+ char *oname = g_path_get_basename(oldpath);
+ char *nname = g_path_get_basename(newpath);
+ V9fsPath olddir, newdir;
+
+ v9fs_path_init_dirname(&olddir, oldpath);
+ v9fs_path_init_dirname(&newdir, newpath);
+
+ err = local_renameat(ctx, &olddir, oname, &newdir, nname);
+
+ v9fs_path_free(&newdir);
+ v9fs_path_free(&olddir);
+ g_free(nname);
+ g_free(oname);
+
+ return err;
+}
+
+static int local_unlinkat(FsContext *ctx, V9fsPath *dir,
+ const char *name, int flags)
+{
+ int ret;
+ int dirfd;
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE &&
+ local_is_mapped_file_metadata(ctx, name)) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ dirfd = local_opendir_nofollow(ctx, dir->data);
+ if (dirfd == -1) {
+ return -1;
+ }
+
+ ret = local_unlinkat_common(ctx, dirfd, name, flags);
+ close_preserve_errno(dirfd);
+ return ret;
+}
+
+#ifdef FS_IOC_GETVERSION
+static int local_ioc_getversion(FsContext *ctx, V9fsPath *path,
+ mode_t st_mode, uint64_t *st_gen)
+{
+ 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;
+}
+#endif
+
+static int local_ioc_getversion_init(FsContext *ctx, LocalData *data, Error **errp)
+{
+#ifdef FS_IOC_GETVERSION
+ struct statfs stbuf;
+
+ /*
+ * use ioc_getversion only if the ioctl is definied
+ */
+ if (fstatfs(data->mountfd, &stbuf) < 0) {
+ error_setg_errno(errp, errno,
+ "failed to stat file system at '%s'", ctx->fs_root);
+ return -1;
+ }
+ 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 0;
+}
+
+static int local_init(FsContext *ctx, Error **errp)
+{
+ LocalData *data = g_malloc(sizeof(*data));
+
+ data->mountfd = open(ctx->fs_root, O_DIRECTORY | O_RDONLY);
+ if (data->mountfd == -1) {
+ error_setg_errno(errp, errno, "failed to open '%s'", ctx->fs_root);
+ goto err;
+ }
+
+ if (local_ioc_getversion_init(ctx, data, errp) < 0) {
+ close(data->mountfd);
+ goto err;
+ }
+
+ 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;
+
+ ctx->private = data;
+ return 0;
+
+err:
+ g_free(data);
+ return -1;
+}
+
+static void local_cleanup(FsContext *ctx)
+{
+ LocalData *data = ctx->private;
+
+ if (!data) {
+ return;
+ }
+
+ close(data->mountfd);
+ g_free(data);
+}
+
+static void error_append_security_model_hint(Error *const *errp)
+{
+ error_append_hint(errp, "Valid options are: security_model="
+ "[passthrough|mapped-xattr|mapped-file|none]\n");
+}
+
+static int local_parse_opts(QemuOpts *opts, FsDriverEntry *fse, Error **errp)
+{
+ ERRP_GUARD();
+ const char *sec_model = qemu_opt_get(opts, "security_model");
+ const char *path = qemu_opt_get(opts, "path");
+ const char *multidevs = qemu_opt_get(opts, "multidevs");
+
+ if (!sec_model) {
+ error_setg(errp, "security_model property not set");
+ error_append_security_model_hint(errp);
+ 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 {
+ error_setg(errp, "invalid security_model property '%s'", sec_model);
+ error_append_security_model_hint(errp);
+ return -1;
+ }
+
+ if (multidevs) {
+ if (!strcmp(multidevs, "remap")) {
+ fse->export_flags &= ~V9FS_FORBID_MULTIDEVS;
+ fse->export_flags |= V9FS_REMAP_INODES;
+ } else if (!strcmp(multidevs, "forbid")) {
+ fse->export_flags &= ~V9FS_REMAP_INODES;
+ fse->export_flags |= V9FS_FORBID_MULTIDEVS;
+ } else if (!strcmp(multidevs, "warn")) {
+ fse->export_flags &= ~V9FS_FORBID_MULTIDEVS;
+ fse->export_flags &= ~V9FS_REMAP_INODES;
+ } else {
+ error_setg(errp, "invalid multidevs property '%s'",
+ multidevs);
+ error_append_hint(errp, "Valid options are: multidevs="
+ "[remap|forbid|warn]\n");
+ return -1;
+ }
+ }
+
+ if (!path) {
+ error_setg(errp, "path property not set");
+ return -1;
+ }
+
+ if (fsdev_throttle_parse_opts(opts, &fse->fst, errp)) {
+ error_prepend(errp, "invalid throttle configuration: ");
+ return -1;
+ }
+
+ if (fse->export_flags & V9FS_SM_MAPPED ||
+ fse->export_flags & V9FS_SM_MAPPED_FILE) {
+ fse->fmode =
+ qemu_opt_get_number(opts, "fmode", SM_LOCAL_MODE_BITS) & 0777;
+ fse->dmode =
+ qemu_opt_get_number(opts, "dmode", SM_LOCAL_DIR_MODE_BITS) & 0777;
+ } else {
+ if (qemu_opt_find(opts, "fmode")) {
+ error_setg(errp, "fmode is only valid for mapped security modes");
+ return -1;
+ }
+ if (qemu_opt_find(opts, "dmode")) {
+ error_setg(errp, "dmode is only valid for mapped security modes");
+ return -1;
+ }
+ }
+
+ fse->path = g_strdup(path);
+
+ return 0;
+}
+
+FileOperations local_ops = {
+ .parse_opts = local_parse_opts,
+ .init = local_init,
+ .cleanup = local_cleanup,
+ .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 = local_readdir,
+ .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,
+};