4 * Copyright IBM, Corp. 2011
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
16 #include <arpa/inet.h>
19 #include <sys/socket.h>
21 #include "qemu/xattr.h"
24 #ifdef CONFIG_LINUX_MAGIC_H
25 #include <linux/magic.h>
27 #include <sys/ioctl.h>
29 #ifndef XFS_SUPER_MAGIC
30 #define XFS_SUPER_MAGIC 0x58465342
32 #ifndef EXT2_SUPER_MAGIC
33 #define EXT2_SUPER_MAGIC 0xEF53
35 #ifndef REISERFS_SUPER_MAGIC
36 #define REISERFS_SUPER_MAGIC 0x52654973
38 #ifndef BTRFS_SUPER_MAGIC
39 #define BTRFS_SUPER_MAGIC 0x9123683E
47 static inline int name_to_handle(int dirfd, const char *name,
48 struct file_handle *fh, int *mnt_id, int flags)
50 return name_to_handle_at(dirfd, name, fh, mnt_id, flags);
53 static inline int open_by_handle(int mountfd, const char *fh, int flags)
55 return open_by_handle_at(mountfd, (struct file_handle *)fh, flags);
58 static int handle_update_file_cred(int dirfd, const char *name, FsCred *credp)
61 fd = openat(dirfd, name, O_NONBLOCK | O_NOFOLLOW);
65 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
69 ret = fchmod(fd, credp->fc_mode & 07777);
76 static int handle_lstat(FsContext *fs_ctx, V9fsPath *fs_path,
80 struct handle_data *data = (struct handle_data *)fs_ctx->private;
82 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
86 ret = fstatat(fd, "", stbuf, AT_EMPTY_PATH);
91 static ssize_t handle_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
92 char *buf, size_t bufsz)
95 struct handle_data *data = (struct handle_data *)fs_ctx->private;
97 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
101 ret = readlinkat(fd, "", buf, bufsz);
106 static int handle_close(FsContext *ctx, V9fsFidOpenState *fs)
108 return close(fs->fd);
111 static int handle_closedir(FsContext *ctx, V9fsFidOpenState *fs)
113 return closedir(fs->dir);
116 static int handle_open(FsContext *ctx, V9fsPath *fs_path,
117 int flags, V9fsFidOpenState *fs)
119 struct handle_data *data = (struct handle_data *)ctx->private;
121 fs->fd = open_by_handle(data->mountfd, fs_path->data, flags);
125 static int handle_opendir(FsContext *ctx,
126 V9fsPath *fs_path, V9fsFidOpenState *fs)
129 ret = handle_open(ctx, fs_path, O_DIRECTORY, fs);
133 fs->dir = fdopendir(ret);
140 static void handle_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
145 static off_t handle_telldir(FsContext *ctx, V9fsFidOpenState *fs)
147 return telldir(fs->dir);
150 static int handle_readdir_r(FsContext *ctx, V9fsFidOpenState *fs,
151 struct dirent *entry,
152 struct dirent **result)
154 return readdir_r(fs->dir, entry, result);
157 static void handle_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
159 seekdir(fs->dir, off);
162 static ssize_t handle_preadv(FsContext *ctx, V9fsFidOpenState *fs,
163 const struct iovec *iov,
164 int iovcnt, off_t offset)
167 return preadv(fs->fd, iov, iovcnt, offset);
169 int err = lseek(fs->fd, offset, SEEK_SET);
173 return readv(fs->fd, iov, iovcnt);
178 static ssize_t handle_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
179 const struct iovec *iov,
180 int iovcnt, off_t offset)
184 ret = pwritev(fs->fd, iov, iovcnt, offset);
186 int err = lseek(fs->fd, offset, SEEK_SET);
190 ret = writev(fs->fd, iov, iovcnt);
193 #ifdef CONFIG_SYNC_FILE_RANGE
194 if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) {
196 * Initiate a writeback. This is not a data integrity sync.
197 * We want to ensure that we don't leave dirty pages in the cache
198 * after write when writeout=immediate is sepcified.
200 sync_file_range(fs->fd, offset, ret,
201 SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
207 static int handle_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
210 struct handle_data *data = (struct handle_data *)fs_ctx->private;
212 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
216 ret = fchmod(fd, credp->fc_mode);
221 static int handle_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
222 const char *name, FsCred *credp)
225 struct handle_data *data = (struct handle_data *)fs_ctx->private;
227 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
231 ret = mknodat(dirfd, name, credp->fc_mode, credp->fc_rdev);
233 ret = handle_update_file_cred(dirfd, name, credp);
239 static int handle_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
240 const char *name, FsCred *credp)
243 struct handle_data *data = (struct handle_data *)fs_ctx->private;
245 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
249 ret = mkdirat(dirfd, name, credp->fc_mode);
251 ret = handle_update_file_cred(dirfd, name, credp);
257 static int handle_fstat(FsContext *fs_ctx, int fid_type,
258 V9fsFidOpenState *fs, struct stat *stbuf)
262 if (fid_type == P9_FID_DIR) {
267 return fstat(fd, stbuf);
270 static int handle_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
271 int flags, FsCred *credp, V9fsFidOpenState *fs)
275 struct handle_data *data = (struct handle_data *)fs_ctx->private;
277 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
281 fd = openat(dirfd, name, flags | O_NOFOLLOW, credp->fc_mode);
283 ret = handle_update_file_cred(dirfd, name, credp);
296 static int handle_symlink(FsContext *fs_ctx, const char *oldpath,
297 V9fsPath *dir_path, const char *name, FsCred *credp)
300 struct handle_data *data = (struct handle_data *)fs_ctx->private;
302 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
306 ret = symlinkat(oldpath, dirfd, name);
308 fd = openat(dirfd, name, O_PATH | O_NOFOLLOW);
313 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
321 static int handle_link(FsContext *ctx, V9fsPath *oldpath,
322 V9fsPath *dirpath, const char *name)
324 int oldfd, newdirfd, ret;
325 struct handle_data *data = (struct handle_data *)ctx->private;
327 oldfd = open_by_handle(data->mountfd, oldpath->data, O_PATH);
331 newdirfd = open_by_handle(data->mountfd, dirpath->data, O_PATH);
336 ret = linkat(oldfd, "", newdirfd, name, AT_EMPTY_PATH);
342 static int handle_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
345 struct handle_data *data = (struct handle_data *)ctx->private;
347 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK | O_WRONLY);
351 ret = ftruncate(fd, size);
356 static int handle_rename(FsContext *ctx, const char *oldpath,
363 static int handle_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
366 struct handle_data *data = (struct handle_data *)fs_ctx->private;
368 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
372 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
377 static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path,
378 const struct timespec *buf)
381 #ifdef CONFIG_UTIMENSAT
383 struct handle_data *data = (struct handle_data *)ctx->private;
385 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
389 ret = futimens(fd, buf);
398 static int handle_remove(FsContext *ctx, const char *path)
404 static int handle_fsync(FsContext *ctx, int fid_type,
405 V9fsFidOpenState *fs, int datasync)
409 if (fid_type == P9_FID_DIR) {
416 return qemu_fdatasync(fd);
422 static int handle_statfs(FsContext *ctx, V9fsPath *fs_path,
423 struct statfs *stbuf)
426 struct handle_data *data = (struct handle_data *)ctx->private;
428 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
432 ret = fstatfs(fd, stbuf);
437 static ssize_t handle_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
438 const char *name, void *value, size_t size)
441 struct handle_data *data = (struct handle_data *)ctx->private;
443 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
447 ret = fgetxattr(fd, name, value, size);
452 static ssize_t handle_llistxattr(FsContext *ctx, V9fsPath *fs_path,
453 void *value, size_t size)
456 struct handle_data *data = (struct handle_data *)ctx->private;
458 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
462 ret = flistxattr(fd, value, size);
467 static int handle_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
468 void *value, size_t size, int flags)
471 struct handle_data *data = (struct handle_data *)ctx->private;
473 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
477 ret = fsetxattr(fd, name, value, size, flags);
482 static int handle_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
486 struct handle_data *data = (struct handle_data *)ctx->private;
488 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
492 ret = fremovexattr(fd, name);
497 static int handle_name_to_path(FsContext *ctx, V9fsPath *dir_path,
498 const char *name, V9fsPath *target)
501 struct file_handle *fh;
502 int dirfd, ret, mnt_id;
503 struct handle_data *data = (struct handle_data *)ctx->private;
505 /* "." and ".." are not allowed */
506 if (!strcmp(name, ".") || !strcmp(name, "..")) {
512 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
514 /* relative to export root */
515 buffer = rpath(ctx, ".");
516 dirfd = open(buffer, O_DIRECTORY);
522 fh = g_malloc(sizeof(struct file_handle) + data->handle_bytes);
523 fh->handle_bytes = data->handle_bytes;
524 /* add a "./" at the beginning of the path */
525 buffer = g_strdup_printf("./%s", name);
526 /* flag = 0 imply don't follow symlink */
527 ret = name_to_handle(dirfd, buffer, fh, &mnt_id, 0);
529 target->data = (char *)fh;
530 target->size = sizeof(struct file_handle) + data->handle_bytes;
539 static int handle_renameat(FsContext *ctx, V9fsPath *olddir,
540 const char *old_name, V9fsPath *newdir,
541 const char *new_name)
543 int olddirfd, newdirfd, ret;
544 struct handle_data *data = (struct handle_data *)ctx->private;
546 olddirfd = open_by_handle(data->mountfd, olddir->data, O_PATH);
550 newdirfd = open_by_handle(data->mountfd, newdir->data, O_PATH);
555 ret = renameat(olddirfd, old_name, newdirfd, new_name);
561 static int handle_unlinkat(FsContext *ctx, V9fsPath *dir,
562 const char *name, int flags)
565 struct handle_data *data = (struct handle_data *)ctx->private;
568 dirfd = open_by_handle(data->mountfd, dir->data, O_PATH);
574 if (flags & P9_DOTL_AT_REMOVEDIR) {
575 rflags |= AT_REMOVEDIR;
578 ret = unlinkat(dirfd, name, rflags);
584 static int handle_ioc_getversion(FsContext *ctx, V9fsPath *path,
585 mode_t st_mode, uint64_t *st_gen)
587 #ifdef FS_IOC_GETVERSION
589 V9fsFidOpenState fid_open;
592 * Do not try to open special files like device nodes, fifos etc
593 * We can get fd for regular files and directories only
595 if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
599 err = handle_open(ctx, path, O_RDONLY, &fid_open);
603 err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
604 handle_close(ctx, &fid_open);
612 static int handle_init(FsContext *ctx)
616 struct file_handle fh;
617 struct handle_data *data = g_malloc(sizeof(struct handle_data));
619 data->mountfd = open(ctx->fs_root, O_DIRECTORY);
620 if (data->mountfd < 0) {
624 ret = statfs(ctx->fs_root, &stbuf);
626 switch (stbuf.f_type) {
627 case EXT2_SUPER_MAGIC:
628 case BTRFS_SUPER_MAGIC:
629 case REISERFS_SUPER_MAGIC:
630 case XFS_SUPER_MAGIC:
631 ctx->exops.get_st_gen = handle_ioc_getversion;
635 memset(&fh, 0, sizeof(struct file_handle));
636 ret = name_to_handle(data->mountfd, ".", &fh, &mnt_id, 0);
637 if (ret && errno == EOVERFLOW) {
638 data->handle_bytes = fh.handle_bytes;
643 /* we got 0 byte handle ? */
645 close(data->mountfd);
652 static int handle_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse)
654 const char *sec_model = qemu_opt_get(opts, "security_model");
655 const char *path = qemu_opt_get(opts, "path");
658 fprintf(stderr, "Invalid argument security_model specified with handle fsdriver\n");
663 fprintf(stderr, "fsdev: No path specified.\n");
666 fse->path = g_strdup(path);
671 FileOperations handle_ops = {
672 .parse_opts = handle_parse_opts,
674 .lstat = handle_lstat,
675 .readlink = handle_readlink,
676 .close = handle_close,
677 .closedir = handle_closedir,
679 .opendir = handle_opendir,
680 .rewinddir = handle_rewinddir,
681 .telldir = handle_telldir,
682 .readdir_r = handle_readdir_r,
683 .seekdir = handle_seekdir,
684 .preadv = handle_preadv,
685 .pwritev = handle_pwritev,
686 .chmod = handle_chmod,
687 .mknod = handle_mknod,
688 .mkdir = handle_mkdir,
689 .fstat = handle_fstat,
690 .open2 = handle_open2,
691 .symlink = handle_symlink,
693 .truncate = handle_truncate,
694 .rename = handle_rename,
695 .chown = handle_chown,
696 .utimensat = handle_utimensat,
697 .remove = handle_remove,
698 .fsync = handle_fsync,
699 .statfs = handle_statfs,
700 .lgetxattr = handle_lgetxattr,
701 .llistxattr = handle_llistxattr,
702 .lsetxattr = handle_lsetxattr,
703 .lremovexattr = handle_lremovexattr,
704 .name_to_path = handle_name_to_path,
705 .renameat = handle_renameat,
706 .unlinkat = handle_unlinkat,