4 * Copyright IBM, Corp. 2011
7 * Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
14 #include "qemu/osdep.h"
17 #include <arpa/inet.h>
20 #include <sys/socket.h>
22 #include "qemu/xattr.h"
23 #include "qemu/cutils.h"
24 #include "qemu/error-report.h"
26 #ifdef CONFIG_LINUX_MAGIC_H
27 #include <linux/magic.h>
29 #include <sys/ioctl.h>
31 #ifndef XFS_SUPER_MAGIC
32 #define XFS_SUPER_MAGIC 0x58465342
34 #ifndef EXT2_SUPER_MAGIC
35 #define EXT2_SUPER_MAGIC 0xEF53
37 #ifndef REISERFS_SUPER_MAGIC
38 #define REISERFS_SUPER_MAGIC 0x52654973
40 #ifndef BTRFS_SUPER_MAGIC
41 #define BTRFS_SUPER_MAGIC 0x9123683E
49 static inline int name_to_handle(int dirfd, const char *name,
50 struct file_handle *fh, int *mnt_id, int flags)
52 return name_to_handle_at(dirfd, name, fh, mnt_id, flags);
55 static inline int open_by_handle(int mountfd, const char *fh, int flags)
57 return open_by_handle_at(mountfd, (struct file_handle *)fh, flags);
60 static int handle_update_file_cred(int dirfd, const char *name, FsCred *credp)
63 fd = openat(dirfd, name, O_NONBLOCK | O_NOFOLLOW);
67 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
71 ret = fchmod(fd, credp->fc_mode & 07777);
78 static int handle_lstat(FsContext *fs_ctx, V9fsPath *fs_path,
82 struct handle_data *data = (struct handle_data *)fs_ctx->private;
84 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
88 ret = fstatat(fd, "", stbuf, AT_EMPTY_PATH);
93 static ssize_t handle_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
94 char *buf, size_t bufsz)
97 struct handle_data *data = (struct handle_data *)fs_ctx->private;
99 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
103 ret = readlinkat(fd, "", buf, bufsz);
108 static int handle_close(FsContext *ctx, V9fsFidOpenState *fs)
110 return close(fs->fd);
113 static int handle_closedir(FsContext *ctx, V9fsFidOpenState *fs)
115 return closedir(fs->dir);
118 static int handle_open(FsContext *ctx, V9fsPath *fs_path,
119 int flags, V9fsFidOpenState *fs)
121 struct handle_data *data = (struct handle_data *)ctx->private;
123 fs->fd = open_by_handle(data->mountfd, fs_path->data, flags);
127 static int handle_opendir(FsContext *ctx,
128 V9fsPath *fs_path, V9fsFidOpenState *fs)
131 ret = handle_open(ctx, fs_path, O_DIRECTORY, fs);
135 fs->dir = fdopendir(ret);
142 static void handle_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
147 static off_t handle_telldir(FsContext *ctx, V9fsFidOpenState *fs)
149 return telldir(fs->dir);
152 static int handle_readdir_r(FsContext *ctx, V9fsFidOpenState *fs,
153 struct dirent *entry,
154 struct dirent **result)
156 return readdir_r(fs->dir, entry, result);
159 static void handle_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
161 seekdir(fs->dir, off);
164 static ssize_t handle_preadv(FsContext *ctx, V9fsFidOpenState *fs,
165 const struct iovec *iov,
166 int iovcnt, off_t offset)
169 return preadv(fs->fd, iov, iovcnt, offset);
171 int err = lseek(fs->fd, offset, SEEK_SET);
175 return readv(fs->fd, iov, iovcnt);
180 static ssize_t handle_pwritev(FsContext *ctx, V9fsFidOpenState *fs,
181 const struct iovec *iov,
182 int iovcnt, off_t offset)
186 ret = pwritev(fs->fd, iov, iovcnt, offset);
188 int err = lseek(fs->fd, offset, SEEK_SET);
192 ret = writev(fs->fd, iov, iovcnt);
195 #ifdef CONFIG_SYNC_FILE_RANGE
196 if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) {
198 * Initiate a writeback. This is not a data integrity sync.
199 * We want to ensure that we don't leave dirty pages in the cache
200 * after write when writeout=immediate is sepcified.
202 sync_file_range(fs->fd, offset, ret,
203 SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE);
209 static int handle_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
212 struct handle_data *data = (struct handle_data *)fs_ctx->private;
214 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
218 ret = fchmod(fd, credp->fc_mode);
223 static int handle_mknod(FsContext *fs_ctx, V9fsPath *dir_path,
224 const char *name, FsCred *credp)
227 struct handle_data *data = (struct handle_data *)fs_ctx->private;
229 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
233 ret = mknodat(dirfd, name, credp->fc_mode, credp->fc_rdev);
235 ret = handle_update_file_cred(dirfd, name, credp);
241 static int handle_mkdir(FsContext *fs_ctx, V9fsPath *dir_path,
242 const char *name, FsCred *credp)
245 struct handle_data *data = (struct handle_data *)fs_ctx->private;
247 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
251 ret = mkdirat(dirfd, name, credp->fc_mode);
253 ret = handle_update_file_cred(dirfd, name, credp);
259 static int handle_fstat(FsContext *fs_ctx, int fid_type,
260 V9fsFidOpenState *fs, struct stat *stbuf)
264 if (fid_type == P9_FID_DIR) {
269 return fstat(fd, stbuf);
272 static int handle_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name,
273 int flags, FsCred *credp, V9fsFidOpenState *fs)
277 struct handle_data *data = (struct handle_data *)fs_ctx->private;
279 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
283 fd = openat(dirfd, name, flags | O_NOFOLLOW, credp->fc_mode);
285 ret = handle_update_file_cred(dirfd, name, credp);
298 static int handle_symlink(FsContext *fs_ctx, const char *oldpath,
299 V9fsPath *dir_path, const char *name, FsCred *credp)
302 struct handle_data *data = (struct handle_data *)fs_ctx->private;
304 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
308 ret = symlinkat(oldpath, dirfd, name);
310 fd = openat(dirfd, name, O_PATH | O_NOFOLLOW);
315 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
323 static int handle_link(FsContext *ctx, V9fsPath *oldpath,
324 V9fsPath *dirpath, const char *name)
326 int oldfd, newdirfd, ret;
327 struct handle_data *data = (struct handle_data *)ctx->private;
329 oldfd = open_by_handle(data->mountfd, oldpath->data, O_PATH);
333 newdirfd = open_by_handle(data->mountfd, dirpath->data, O_PATH);
338 ret = linkat(oldfd, "", newdirfd, name, AT_EMPTY_PATH);
344 static int handle_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size)
347 struct handle_data *data = (struct handle_data *)ctx->private;
349 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK | O_WRONLY);
353 ret = ftruncate(fd, size);
358 static int handle_rename(FsContext *ctx, const char *oldpath,
365 static int handle_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
368 struct handle_data *data = (struct handle_data *)fs_ctx->private;
370 fd = open_by_handle(data->mountfd, fs_path->data, O_PATH);
374 ret = fchownat(fd, "", credp->fc_uid, credp->fc_gid, AT_EMPTY_PATH);
379 static int handle_utimensat(FsContext *ctx, V9fsPath *fs_path,
380 const struct timespec *buf)
383 #ifdef CONFIG_UTIMENSAT
385 struct handle_data *data = (struct handle_data *)ctx->private;
387 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
391 ret = futimens(fd, buf);
400 static int handle_remove(FsContext *ctx, const char *path)
406 static int handle_fsync(FsContext *ctx, int fid_type,
407 V9fsFidOpenState *fs, int datasync)
411 if (fid_type == P9_FID_DIR) {
418 return qemu_fdatasync(fd);
424 static int handle_statfs(FsContext *ctx, V9fsPath *fs_path,
425 struct statfs *stbuf)
428 struct handle_data *data = (struct handle_data *)ctx->private;
430 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
434 ret = fstatfs(fd, stbuf);
439 static ssize_t handle_lgetxattr(FsContext *ctx, V9fsPath *fs_path,
440 const char *name, void *value, size_t size)
443 struct handle_data *data = (struct handle_data *)ctx->private;
445 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
449 ret = fgetxattr(fd, name, value, size);
454 static ssize_t handle_llistxattr(FsContext *ctx, V9fsPath *fs_path,
455 void *value, size_t size)
458 struct handle_data *data = (struct handle_data *)ctx->private;
460 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
464 ret = flistxattr(fd, value, size);
469 static int handle_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name,
470 void *value, size_t size, int flags)
473 struct handle_data *data = (struct handle_data *)ctx->private;
475 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
479 ret = fsetxattr(fd, name, value, size, flags);
484 static int handle_lremovexattr(FsContext *ctx, V9fsPath *fs_path,
488 struct handle_data *data = (struct handle_data *)ctx->private;
490 fd = open_by_handle(data->mountfd, fs_path->data, O_NONBLOCK);
494 ret = fremovexattr(fd, name);
499 static int handle_name_to_path(FsContext *ctx, V9fsPath *dir_path,
500 const char *name, V9fsPath *target)
503 struct file_handle *fh;
504 int dirfd, ret, mnt_id;
505 struct handle_data *data = (struct handle_data *)ctx->private;
507 /* "." and ".." are not allowed */
508 if (!strcmp(name, ".") || !strcmp(name, "..")) {
514 dirfd = open_by_handle(data->mountfd, dir_path->data, O_PATH);
516 /* relative to export root */
517 buffer = rpath(ctx, ".");
518 dirfd = open(buffer, O_DIRECTORY);
524 fh = g_malloc(sizeof(struct file_handle) + data->handle_bytes);
525 fh->handle_bytes = data->handle_bytes;
526 /* add a "./" at the beginning of the path */
527 buffer = g_strdup_printf("./%s", name);
528 /* flag = 0 imply don't follow symlink */
529 ret = name_to_handle(dirfd, buffer, fh, &mnt_id, 0);
531 target->data = (char *)fh;
532 target->size = sizeof(struct file_handle) + data->handle_bytes;
541 static int handle_renameat(FsContext *ctx, V9fsPath *olddir,
542 const char *old_name, V9fsPath *newdir,
543 const char *new_name)
545 int olddirfd, newdirfd, ret;
546 struct handle_data *data = (struct handle_data *)ctx->private;
548 olddirfd = open_by_handle(data->mountfd, olddir->data, O_PATH);
552 newdirfd = open_by_handle(data->mountfd, newdir->data, O_PATH);
557 ret = renameat(olddirfd, old_name, newdirfd, new_name);
563 static int handle_unlinkat(FsContext *ctx, V9fsPath *dir,
564 const char *name, int flags)
567 struct handle_data *data = (struct handle_data *)ctx->private;
570 dirfd = open_by_handle(data->mountfd, dir->data, O_PATH);
576 if (flags & P9_DOTL_AT_REMOVEDIR) {
577 rflags |= AT_REMOVEDIR;
580 ret = unlinkat(dirfd, name, rflags);
586 static int handle_ioc_getversion(FsContext *ctx, V9fsPath *path,
587 mode_t st_mode, uint64_t *st_gen)
589 #ifdef FS_IOC_GETVERSION
591 V9fsFidOpenState fid_open;
594 * Do not try to open special files like device nodes, fifos etc
595 * We can get fd for regular files and directories only
597 if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) {
601 err = handle_open(ctx, path, O_RDONLY, &fid_open);
605 err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen);
606 handle_close(ctx, &fid_open);
614 static int handle_init(FsContext *ctx)
618 struct file_handle fh;
619 struct handle_data *data = g_malloc(sizeof(struct handle_data));
621 data->mountfd = open(ctx->fs_root, O_DIRECTORY);
622 if (data->mountfd < 0) {
626 ret = statfs(ctx->fs_root, &stbuf);
628 switch (stbuf.f_type) {
629 case EXT2_SUPER_MAGIC:
630 case BTRFS_SUPER_MAGIC:
631 case REISERFS_SUPER_MAGIC:
632 case XFS_SUPER_MAGIC:
633 ctx->exops.get_st_gen = handle_ioc_getversion;
637 memset(&fh, 0, sizeof(struct file_handle));
638 ret = name_to_handle(data->mountfd, ".", &fh, &mnt_id, 0);
639 if (ret && errno == EOVERFLOW) {
640 data->handle_bytes = fh.handle_bytes;
645 /* we got 0 byte handle ? */
647 close(data->mountfd);
654 static int handle_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse)
656 const char *sec_model = qemu_opt_get(opts, "security_model");
657 const char *path = qemu_opt_get(opts, "path");
660 error_report("Invalid argument security_model specified with handle fsdriver");
665 error_report("fsdev: No path specified");
668 fse->path = g_strdup(path);
673 FileOperations handle_ops = {
674 .parse_opts = handle_parse_opts,
676 .lstat = handle_lstat,
677 .readlink = handle_readlink,
678 .close = handle_close,
679 .closedir = handle_closedir,
681 .opendir = handle_opendir,
682 .rewinddir = handle_rewinddir,
683 .telldir = handle_telldir,
684 .readdir_r = handle_readdir_r,
685 .seekdir = handle_seekdir,
686 .preadv = handle_preadv,
687 .pwritev = handle_pwritev,
688 .chmod = handle_chmod,
689 .mknod = handle_mknod,
690 .mkdir = handle_mkdir,
691 .fstat = handle_fstat,
692 .open2 = handle_open2,
693 .symlink = handle_symlink,
695 .truncate = handle_truncate,
696 .rename = handle_rename,
697 .chown = handle_chown,
698 .utimensat = handle_utimensat,
699 .remove = handle_remove,
700 .fsync = handle_fsync,
701 .statfs = handle_statfs,
702 .lgetxattr = handle_lgetxattr,
703 .llistxattr = handle_llistxattr,
704 .lsetxattr = handle_lsetxattr,
705 .lremovexattr = handle_lremovexattr,
706 .name_to_path = handle_name_to_path,
707 .renameat = handle_renameat,
708 .unlinkat = handle_unlinkat,