|  | /* | 
|  | * 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> | 
|  | #ifdef CONFIG_LINUX | 
|  | #include <linux/fs.h> | 
|  | #ifdef CONFIG_LINUX_MAGIC_H | 
|  | #include <linux/magic.h> | 
|  | #endif | 
|  | #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; | 
|  | qemu_renameat(odirfd, opath, ndirfd, npath); | 
|  | errno = serrno; | 
|  | } | 
|  |  | 
|  | static void unlinkat_preserve_errno(int dirfd, const char *path, int flags) | 
|  | { | 
|  | int serrno = errno; | 
|  | qemu_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 = qemu_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 = qemu_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 (qemu_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; | 
|  | } | 
|  | tsize = RETRY_ON_EINTR(read(fd, (void *)buf, bufsz)); | 
|  | 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; | 
|  | } | 
|  | #ifdef CONFIG_DARWIN | 
|  | int off; | 
|  | off = telldir(fs->dir.stream); | 
|  | /* If telldir fails, fail the entire readdir call */ | 
|  | if (off < 0) { | 
|  | return NULL; | 
|  | } | 
|  | entry->d_seekoff = off; | 
|  | #endif | 
|  |  | 
|  | 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 specified. | 
|  | */ | 
|  | 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 = qemu_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 = qemu_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 = qemu_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 = qemu_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 (qemu_fgetxattr(fd, "user.virtfs.uid", | 
|  | &tmp_uid, sizeof(uid_t)) > 0) { | 
|  | stbuf->st_uid = le32_to_cpu(tmp_uid); | 
|  | } | 
|  | if (qemu_fgetxattr(fd, "user.virtfs.gid", | 
|  | &tmp_gid, sizeof(gid_t)) > 0) { | 
|  | stbuf->st_gid = le32_to_cpu(tmp_gid); | 
|  | } | 
|  | if (qemu_fgetxattr(fd, "user.virtfs.mode", | 
|  | &tmp_mode, sizeof(mode_t)) > 0) { | 
|  | stbuf->st_mode = le32_to_cpu(tmp_mode); | 
|  | } | 
|  | if (qemu_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 client 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); | 
|  | write_size = RETRY_ON_EINTR(write(fd, (void *)oldpath, oldpath_size)); | 
|  | close_preserve_errno(fd); | 
|  |  | 
|  | if (write_size != oldpath_size) { | 
|  | goto err_end; | 
|  | } | 
|  | /* Set client 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 = qemu_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 = qemu_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 = qemu_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 = qemu_unlinkat(map_dirfd, name, 0); | 
|  | close_preserve_errno(map_dirfd); | 
|  | if (ret < 0 && errno != ENOENT) { | 
|  | return -1; | 
|  | } | 
|  | } else if (errno != ENOENT) { | 
|  | return -1; | 
|  | } | 
|  | } | 
|  |  | 
|  | return qemu_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 (qemu_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 = qemu_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 = qemu_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 = qemu_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 defined | 
|  | */ | 
|  | 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, | 
|  | }; |