tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2#ifndef NO_BCACHEFS_FS
3
4#include "bcachefs.h"
5#include "chardev.h"
6#include "dirent.h"
7#include "fs.h"
8#include "fs-common.h"
9#include "fs-ioctl.h"
10#include "quota.h"
11
12#include <linux/compat.h>
13#include <linux/fsnotify.h>
14#include <linux/mount.h>
15#include <linux/namei.h>
16#include <linux/security.h>
17#include <linux/writeback.h>
18
19#define FS_IOC_GOINGDOWN _IOR('X', 125, __u32)
20#define FSOP_GOING_FLAGS_DEFAULT 0x0 /* going down */
21#define FSOP_GOING_FLAGS_LOGFLUSH 0x1 /* flush log but not data */
22#define FSOP_GOING_FLAGS_NOLOGFLUSH 0x2 /* don't flush log nor data */
23
24struct flags_set {
25 unsigned mask;
26 unsigned flags;
27
28 unsigned projid;
29
30 bool set_projinherit;
31 bool projinherit;
32};
33
34static int bch2_inode_flags_set(struct btree_trans *trans,
35 struct bch_inode_info *inode,
36 struct bch_inode_unpacked *bi,
37 void *p)
38{
39 struct bch_fs *c = inode->v.i_sb->s_fs_info;
40 /*
41 * We're relying on btree locking here for exclusion with other ioctl
42 * calls - use the flags in the btree (@bi), not inode->i_flags:
43 */
44 struct flags_set *s = p;
45 unsigned newflags = s->flags;
46 unsigned oldflags = bi->bi_flags & s->mask;
47
48 if (((newflags ^ oldflags) & (BCH_INODE_append|BCH_INODE_immutable)) &&
49 !capable(CAP_LINUX_IMMUTABLE))
50 return -EPERM;
51
52 if (!S_ISREG(bi->bi_mode) &&
53 !S_ISDIR(bi->bi_mode) &&
54 (newflags & (BCH_INODE_nodump|BCH_INODE_noatime)) != newflags)
55 return -EINVAL;
56
57 if (s->set_projinherit) {
58 bi->bi_fields_set &= ~(1 << Inode_opt_project);
59 bi->bi_fields_set |= ((int) s->projinherit << Inode_opt_project);
60 }
61
62 bi->bi_flags &= ~s->mask;
63 bi->bi_flags |= newflags;
64
65 bi->bi_ctime = timespec_to_bch2_time(c, current_time(&inode->v));
66 return 0;
67}
68
69static int bch2_ioc_getflags(struct bch_inode_info *inode, int __user *arg)
70{
71 unsigned flags = map_flags(bch_flags_to_uflags, inode->ei_inode.bi_flags);
72
73 return put_user(flags, arg);
74}
75
76static int bch2_ioc_setflags(struct bch_fs *c,
77 struct file *file,
78 struct bch_inode_info *inode,
79 void __user *arg)
80{
81 struct flags_set s = { .mask = map_defined(bch_flags_to_uflags) };
82 unsigned uflags;
83 int ret;
84
85 if (get_user(uflags, (int __user *) arg))
86 return -EFAULT;
87
88 s.flags = map_flags_rev(bch_flags_to_uflags, uflags);
89 if (uflags)
90 return -EOPNOTSUPP;
91
92 ret = mnt_want_write_file(file);
93 if (ret)
94 return ret;
95
96 inode_lock(&inode->v);
97 if (!inode_owner_or_capable(file_mnt_idmap(file), &inode->v)) {
98 ret = -EACCES;
99 goto setflags_out;
100 }
101
102 mutex_lock(&inode->ei_update_lock);
103 ret = bch2_subvol_is_ro(c, inode->ei_subvol) ?:
104 bch2_write_inode(c, inode, bch2_inode_flags_set, &s,
105 ATTR_CTIME);
106 mutex_unlock(&inode->ei_update_lock);
107
108setflags_out:
109 inode_unlock(&inode->v);
110 mnt_drop_write_file(file);
111 return ret;
112}
113
114static int bch2_ioc_fsgetxattr(struct bch_inode_info *inode,
115 struct fsxattr __user *arg)
116{
117 struct fsxattr fa = { 0 };
118
119 fa.fsx_xflags = map_flags(bch_flags_to_xflags, inode->ei_inode.bi_flags);
120
121 if (inode->ei_inode.bi_fields_set & (1 << Inode_opt_project))
122 fa.fsx_xflags |= FS_XFLAG_PROJINHERIT;
123
124 fa.fsx_projid = inode->ei_qid.q[QTYP_PRJ];
125
126 if (copy_to_user(arg, &fa, sizeof(fa)))
127 return -EFAULT;
128
129 return 0;
130}
131
132static int fssetxattr_inode_update_fn(struct btree_trans *trans,
133 struct bch_inode_info *inode,
134 struct bch_inode_unpacked *bi,
135 void *p)
136{
137 struct flags_set *s = p;
138
139 if (s->projid != bi->bi_project) {
140 bi->bi_fields_set |= 1U << Inode_opt_project;
141 bi->bi_project = s->projid;
142 }
143
144 return bch2_inode_flags_set(trans, inode, bi, p);
145}
146
147static int bch2_ioc_fssetxattr(struct bch_fs *c,
148 struct file *file,
149 struct bch_inode_info *inode,
150 struct fsxattr __user *arg)
151{
152 struct flags_set s = { .mask = map_defined(bch_flags_to_xflags) };
153 struct fsxattr fa;
154 int ret;
155
156 if (copy_from_user(&fa, arg, sizeof(fa)))
157 return -EFAULT;
158
159 s.set_projinherit = true;
160 s.projinherit = (fa.fsx_xflags & FS_XFLAG_PROJINHERIT) != 0;
161 fa.fsx_xflags &= ~FS_XFLAG_PROJINHERIT;
162
163 s.flags = map_flags_rev(bch_flags_to_xflags, fa.fsx_xflags);
164 if (fa.fsx_xflags)
165 return -EOPNOTSUPP;
166
167 if (fa.fsx_projid >= U32_MAX)
168 return -EINVAL;
169
170 /*
171 * inode fields accessible via the xattr interface are stored with a +1
172 * bias, so that 0 means unset:
173 */
174 s.projid = fa.fsx_projid + 1;
175
176 ret = mnt_want_write_file(file);
177 if (ret)
178 return ret;
179
180 inode_lock(&inode->v);
181 if (!inode_owner_or_capable(file_mnt_idmap(file), &inode->v)) {
182 ret = -EACCES;
183 goto err;
184 }
185
186 mutex_lock(&inode->ei_update_lock);
187 ret = bch2_subvol_is_ro(c, inode->ei_subvol) ?:
188 bch2_set_projid(c, inode, fa.fsx_projid) ?:
189 bch2_write_inode(c, inode, fssetxattr_inode_update_fn, &s,
190 ATTR_CTIME);
191 mutex_unlock(&inode->ei_update_lock);
192err:
193 inode_unlock(&inode->v);
194 mnt_drop_write_file(file);
195 return ret;
196}
197
198static int bch2_reinherit_attrs_fn(struct btree_trans *trans,
199 struct bch_inode_info *inode,
200 struct bch_inode_unpacked *bi,
201 void *p)
202{
203 struct bch_inode_info *dir = p;
204
205 return !bch2_reinherit_attrs(bi, &dir->ei_inode);
206}
207
208static int bch2_ioc_reinherit_attrs(struct bch_fs *c,
209 struct file *file,
210 struct bch_inode_info *src,
211 const char __user *name)
212{
213 struct bch_hash_info hash = bch2_hash_info_init(c, &src->ei_inode);
214 struct bch_inode_info *dst;
215 struct inode *vinode = NULL;
216 char *kname = NULL;
217 struct qstr qstr;
218 int ret = 0;
219 subvol_inum inum;
220
221 kname = kmalloc(BCH_NAME_MAX + 1, GFP_KERNEL);
222 if (!kname)
223 return -ENOMEM;
224
225 ret = strncpy_from_user(kname, name, BCH_NAME_MAX);
226 if (unlikely(ret < 0))
227 goto err1;
228
229 qstr.len = ret;
230 qstr.name = kname;
231
232 ret = bch2_dirent_lookup(c, inode_inum(src), &hash, &qstr, &inum);
233 if (ret)
234 goto err1;
235
236 vinode = bch2_vfs_inode_get(c, inum);
237 ret = PTR_ERR_OR_ZERO(vinode);
238 if (ret)
239 goto err1;
240
241 dst = to_bch_ei(vinode);
242
243 ret = mnt_want_write_file(file);
244 if (ret)
245 goto err2;
246
247 bch2_lock_inodes(INODE_UPDATE_LOCK, src, dst);
248
249 if (inode_attr_changing(src, dst, Inode_opt_project)) {
250 ret = bch2_fs_quota_transfer(c, dst,
251 src->ei_qid,
252 1 << QTYP_PRJ,
253 KEY_TYPE_QUOTA_PREALLOC);
254 if (ret)
255 goto err3;
256 }
257
258 ret = bch2_write_inode(c, dst, bch2_reinherit_attrs_fn, src, 0);
259err3:
260 bch2_unlock_inodes(INODE_UPDATE_LOCK, src, dst);
261
262 /* return true if we did work */
263 if (ret >= 0)
264 ret = !ret;
265
266 mnt_drop_write_file(file);
267err2:
268 iput(vinode);
269err1:
270 kfree(kname);
271
272 return ret;
273}
274
275static int bch2_ioc_goingdown(struct bch_fs *c, u32 __user *arg)
276{
277 u32 flags;
278 int ret = 0;
279
280 if (!capable(CAP_SYS_ADMIN))
281 return -EPERM;
282
283 if (get_user(flags, arg))
284 return -EFAULT;
285
286 bch_notice(c, "shutdown by ioctl type %u", flags);
287
288 down_write(&c->vfs_sb->s_umount);
289
290 switch (flags) {
291 case FSOP_GOING_FLAGS_DEFAULT:
292 ret = freeze_bdev(c->vfs_sb->s_bdev);
293 if (ret)
294 goto err;
295
296 bch2_journal_flush(&c->journal);
297 c->vfs_sb->s_flags |= SB_RDONLY;
298 bch2_fs_emergency_read_only(c);
299 thaw_bdev(c->vfs_sb->s_bdev);
300 break;
301
302 case FSOP_GOING_FLAGS_LOGFLUSH:
303 bch2_journal_flush(&c->journal);
304 fallthrough;
305
306 case FSOP_GOING_FLAGS_NOLOGFLUSH:
307 c->vfs_sb->s_flags |= SB_RDONLY;
308 bch2_fs_emergency_read_only(c);
309 break;
310 default:
311 ret = -EINVAL;
312 break;
313 }
314err:
315 up_write(&c->vfs_sb->s_umount);
316 return ret;
317}
318
319static long __bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp,
320 struct bch_ioctl_subvolume arg)
321{
322 struct inode *dir;
323 struct bch_inode_info *inode;
324 struct user_namespace *s_user_ns;
325 struct dentry *dst_dentry;
326 struct path src_path, dst_path;
327 int how = LOOKUP_FOLLOW;
328 int error;
329 subvol_inum snapshot_src = { 0 };
330 unsigned lookup_flags = 0;
331 unsigned create_flags = BCH_CREATE_SUBVOL;
332
333 if (arg.flags & ~(BCH_SUBVOL_SNAPSHOT_CREATE|
334 BCH_SUBVOL_SNAPSHOT_RO))
335 return -EINVAL;
336
337 if (!(arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) &&
338 (arg.src_ptr ||
339 (arg.flags & BCH_SUBVOL_SNAPSHOT_RO)))
340 return -EINVAL;
341
342 if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE)
343 create_flags |= BCH_CREATE_SNAPSHOT;
344
345 if (arg.flags & BCH_SUBVOL_SNAPSHOT_RO)
346 create_flags |= BCH_CREATE_SNAPSHOT_RO;
347
348 /* why do we need this lock? */
349 down_read(&c->vfs_sb->s_umount);
350
351 if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE)
352 sync_inodes_sb(c->vfs_sb);
353retry:
354 if (arg.src_ptr) {
355 error = user_path_at(arg.dirfd,
356 (const char __user *)(unsigned long)arg.src_ptr,
357 how, &src_path);
358 if (error)
359 goto err1;
360
361 if (src_path.dentry->d_sb->s_fs_info != c) {
362 path_put(&src_path);
363 error = -EXDEV;
364 goto err1;
365 }
366
367 snapshot_src = inode_inum(to_bch_ei(src_path.dentry->d_inode));
368 }
369
370 dst_dentry = user_path_create(arg.dirfd,
371 (const char __user *)(unsigned long)arg.dst_ptr,
372 &dst_path, lookup_flags);
373 error = PTR_ERR_OR_ZERO(dst_dentry);
374 if (error)
375 goto err2;
376
377 if (dst_dentry->d_sb->s_fs_info != c) {
378 error = -EXDEV;
379 goto err3;
380 }
381
382 if (dst_dentry->d_inode) {
383 error = -EEXIST;
384 goto err3;
385 }
386
387 dir = dst_path.dentry->d_inode;
388 if (IS_DEADDIR(dir)) {
389 error = -BCH_ERR_ENOENT_directory_dead;
390 goto err3;
391 }
392
393 s_user_ns = dir->i_sb->s_user_ns;
394 if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
395 !kgid_has_mapping(s_user_ns, current_fsgid())) {
396 error = -EOVERFLOW;
397 goto err3;
398 }
399
400 error = inode_permission(file_mnt_idmap(filp),
401 dir, MAY_WRITE | MAY_EXEC);
402 if (error)
403 goto err3;
404
405 if (!IS_POSIXACL(dir))
406 arg.mode &= ~current_umask();
407
408 error = security_path_mkdir(&dst_path, dst_dentry, arg.mode);
409 if (error)
410 goto err3;
411
412 if ((arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) &&
413 !arg.src_ptr)
414 snapshot_src.subvol = inode_inum(to_bch_ei(dir)).subvol;
415
416 inode = __bch2_create(file_mnt_idmap(filp), to_bch_ei(dir),
417 dst_dentry, arg.mode|S_IFDIR,
418 0, snapshot_src, create_flags);
419 error = PTR_ERR_OR_ZERO(inode);
420 if (error)
421 goto err3;
422
423 d_instantiate(dst_dentry, &inode->v);
424 fsnotify_mkdir(dir, dst_dentry);
425err3:
426 done_path_create(&dst_path, dst_dentry);
427err2:
428 if (arg.src_ptr)
429 path_put(&src_path);
430
431 if (retry_estale(error, lookup_flags)) {
432 lookup_flags |= LOOKUP_REVAL;
433 goto retry;
434 }
435err1:
436 up_read(&c->vfs_sb->s_umount);
437
438 return error;
439}
440
441static long bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp,
442 struct bch_ioctl_subvolume arg)
443{
444 down_write(&c->snapshot_create_lock);
445 long ret = __bch2_ioctl_subvolume_create(c, filp, arg);
446 up_write(&c->snapshot_create_lock);
447
448 return ret;
449}
450
451static long bch2_ioctl_subvolume_destroy(struct bch_fs *c, struct file *filp,
452 struct bch_ioctl_subvolume arg)
453{
454 struct path path;
455 struct inode *dir;
456 int ret = 0;
457
458 if (arg.flags)
459 return -EINVAL;
460
461 ret = user_path_at(arg.dirfd,
462 (const char __user *)(unsigned long)arg.dst_ptr,
463 LOOKUP_FOLLOW, &path);
464 if (ret)
465 return ret;
466
467 if (path.dentry->d_sb->s_fs_info != c) {
468 ret = -EXDEV;
469 goto err;
470 }
471
472 dir = path.dentry->d_parent->d_inode;
473
474 ret = __bch2_unlink(dir, path.dentry, true);
475 if (ret)
476 goto err;
477
478 fsnotify_rmdir(dir, path.dentry);
479 d_delete(path.dentry);
480err:
481 path_put(&path);
482 return ret;
483}
484
485long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg)
486{
487 struct bch_inode_info *inode = file_bch_inode(file);
488 struct bch_fs *c = inode->v.i_sb->s_fs_info;
489 long ret;
490
491 switch (cmd) {
492 case FS_IOC_GETFLAGS:
493 ret = bch2_ioc_getflags(inode, (int __user *) arg);
494 break;
495
496 case FS_IOC_SETFLAGS:
497 ret = bch2_ioc_setflags(c, file, inode, (int __user *) arg);
498 break;
499
500 case FS_IOC_FSGETXATTR:
501 ret = bch2_ioc_fsgetxattr(inode, (void __user *) arg);
502 break;
503
504 case FS_IOC_FSSETXATTR:
505 ret = bch2_ioc_fssetxattr(c, file, inode,
506 (void __user *) arg);
507 break;
508
509 case BCHFS_IOC_REINHERIT_ATTRS:
510 ret = bch2_ioc_reinherit_attrs(c, file, inode,
511 (void __user *) arg);
512 break;
513
514 case FS_IOC_GETVERSION:
515 ret = -ENOTTY;
516 break;
517
518 case FS_IOC_SETVERSION:
519 ret = -ENOTTY;
520 break;
521
522 case FS_IOC_GOINGDOWN:
523 ret = bch2_ioc_goingdown(c, (u32 __user *) arg);
524 break;
525
526 case BCH_IOCTL_SUBVOLUME_CREATE: {
527 struct bch_ioctl_subvolume i;
528
529 ret = copy_from_user(&i, (void __user *) arg, sizeof(i))
530 ? -EFAULT
531 : bch2_ioctl_subvolume_create(c, file, i);
532 break;
533 }
534
535 case BCH_IOCTL_SUBVOLUME_DESTROY: {
536 struct bch_ioctl_subvolume i;
537
538 ret = copy_from_user(&i, (void __user *) arg, sizeof(i))
539 ? -EFAULT
540 : bch2_ioctl_subvolume_destroy(c, file, i);
541 break;
542 }
543
544 default:
545 ret = bch2_fs_ioctl(c, cmd, (void __user *) arg);
546 break;
547 }
548
549 return bch2_err_class(ret);
550}
551
552#ifdef CONFIG_COMPAT
553long bch2_compat_fs_ioctl(struct file *file, unsigned cmd, unsigned long arg)
554{
555 /* These are just misnamed, they actually get/put from/to user an int */
556 switch (cmd) {
557 case FS_IOC_GETFLAGS:
558 cmd = FS_IOC_GETFLAGS;
559 break;
560 case FS_IOC32_SETFLAGS:
561 cmd = FS_IOC_SETFLAGS;
562 break;
563 default:
564 return -ENOIOCTLCMD;
565 }
566 return bch2_fs_file_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
567}
568#endif
569
570#endif /* NO_BCACHEFS_FS */