writeback: add comments to bdi_work structure
[linux-2.6/next.git] / fs / nilfs2 / ioctl.c
blob6572ea4bc4df70498dc62b29b93968d0396c7775
1 /*
2 * ioctl.c - NILFS ioctl operations.
4 * Copyright (C) 2007, 2008 Nippon Telegraph and Telephone Corporation.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 * Written by Koji Sato <koji@osrg.net>.
23 #include <linux/fs.h>
24 #include <linux/wait.h>
25 #include <linux/smp_lock.h> /* lock_kernel(), unlock_kernel() */
26 #include <linux/capability.h> /* capable() */
27 #include <linux/uaccess.h> /* copy_from_user(), copy_to_user() */
28 #include <linux/vmalloc.h>
29 #include <linux/nilfs2_fs.h>
30 #include "nilfs.h"
31 #include "segment.h"
32 #include "bmap.h"
33 #include "cpfile.h"
34 #include "sufile.h"
35 #include "dat.h"
38 static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
39 struct nilfs_argv *argv, int dir,
40 ssize_t (*dofunc)(struct the_nilfs *,
41 __u64 *, int,
42 void *, size_t, size_t))
44 void *buf;
45 void __user *base = (void __user *)(unsigned long)argv->v_base;
46 size_t maxmembs, total, n;
47 ssize_t nr;
48 int ret, i;
49 __u64 pos, ppos;
51 if (argv->v_nmembs == 0)
52 return 0;
54 if (argv->v_size > PAGE_SIZE)
55 return -EINVAL;
57 buf = (void *)__get_free_pages(GFP_NOFS, 0);
58 if (unlikely(!buf))
59 return -ENOMEM;
60 maxmembs = PAGE_SIZE / argv->v_size;
62 ret = 0;
63 total = 0;
64 pos = argv->v_index;
65 for (i = 0; i < argv->v_nmembs; i += n) {
66 n = (argv->v_nmembs - i < maxmembs) ?
67 argv->v_nmembs - i : maxmembs;
68 if ((dir & _IOC_WRITE) &&
69 copy_from_user(buf, base + argv->v_size * i,
70 argv->v_size * n)) {
71 ret = -EFAULT;
72 break;
74 ppos = pos;
75 nr = dofunc(nilfs, &pos, argv->v_flags, buf, argv->v_size,
76 n);
77 if (nr < 0) {
78 ret = nr;
79 break;
81 if ((dir & _IOC_READ) &&
82 copy_to_user(base + argv->v_size * i, buf,
83 argv->v_size * nr)) {
84 ret = -EFAULT;
85 break;
87 total += nr;
88 if ((size_t)nr < n)
89 break;
90 if (pos == ppos)
91 pos += n;
93 argv->v_nmembs = total;
95 free_pages((unsigned long)buf, 0);
96 return ret;
99 static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
100 unsigned int cmd, void __user *argp)
102 struct inode *cpfile = NILFS_SB(inode->i_sb)->s_nilfs->ns_cpfile;
103 struct nilfs_transaction_info ti;
104 struct nilfs_cpmode cpmode;
105 int ret;
107 if (!capable(CAP_SYS_ADMIN))
108 return -EPERM;
109 if (copy_from_user(&cpmode, argp, sizeof(cpmode)))
110 return -EFAULT;
112 nilfs_transaction_begin(inode->i_sb, &ti, 0);
113 ret = nilfs_cpfile_change_cpmode(
114 cpfile, cpmode.cm_cno, cpmode.cm_mode);
115 if (unlikely(ret < 0)) {
116 nilfs_transaction_abort(inode->i_sb);
117 return ret;
119 nilfs_transaction_commit(inode->i_sb); /* never fails */
120 return ret;
123 static int
124 nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
125 unsigned int cmd, void __user *argp)
127 struct inode *cpfile = NILFS_SB(inode->i_sb)->s_nilfs->ns_cpfile;
128 struct nilfs_transaction_info ti;
129 __u64 cno;
130 int ret;
132 if (!capable(CAP_SYS_ADMIN))
133 return -EPERM;
134 if (copy_from_user(&cno, argp, sizeof(cno)))
135 return -EFAULT;
137 nilfs_transaction_begin(inode->i_sb, &ti, 0);
138 ret = nilfs_cpfile_delete_checkpoint(cpfile, cno);
139 if (unlikely(ret < 0)) {
140 nilfs_transaction_abort(inode->i_sb);
141 return ret;
143 nilfs_transaction_commit(inode->i_sb); /* never fails */
144 return ret;
147 static ssize_t
148 nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
149 void *buf, size_t size, size_t nmembs)
151 int ret;
153 down_read(&nilfs->ns_segctor_sem);
154 ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
155 size, nmembs);
156 up_read(&nilfs->ns_segctor_sem);
157 return ret;
160 static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
161 unsigned int cmd, void __user *argp)
163 struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
164 struct nilfs_cpstat cpstat;
165 int ret;
167 down_read(&nilfs->ns_segctor_sem);
168 ret = nilfs_cpfile_get_stat(nilfs->ns_cpfile, &cpstat);
169 up_read(&nilfs->ns_segctor_sem);
170 if (ret < 0)
171 return ret;
173 if (copy_to_user(argp, &cpstat, sizeof(cpstat)))
174 ret = -EFAULT;
175 return ret;
178 static ssize_t
179 nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
180 void *buf, size_t size, size_t nmembs)
182 int ret;
184 down_read(&nilfs->ns_segctor_sem);
185 ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, size,
186 nmembs);
187 up_read(&nilfs->ns_segctor_sem);
188 return ret;
191 static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
192 unsigned int cmd, void __user *argp)
194 struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
195 struct nilfs_sustat sustat;
196 int ret;
198 down_read(&nilfs->ns_segctor_sem);
199 ret = nilfs_sufile_get_stat(nilfs->ns_sufile, &sustat);
200 up_read(&nilfs->ns_segctor_sem);
201 if (ret < 0)
202 return ret;
204 if (copy_to_user(argp, &sustat, sizeof(sustat)))
205 ret = -EFAULT;
206 return ret;
209 static ssize_t
210 nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
211 void *buf, size_t size, size_t nmembs)
213 int ret;
215 down_read(&nilfs->ns_segctor_sem);
216 ret = nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, size, nmembs);
217 up_read(&nilfs->ns_segctor_sem);
218 return ret;
221 static ssize_t
222 nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
223 void *buf, size_t size, size_t nmembs)
225 struct inode *dat = nilfs_dat_inode(nilfs);
226 struct nilfs_bmap *bmap = NILFS_I(dat)->i_bmap;
227 struct nilfs_bdesc *bdescs = buf;
228 int ret, i;
230 down_read(&nilfs->ns_segctor_sem);
231 for (i = 0; i < nmembs; i++) {
232 ret = nilfs_bmap_lookup_at_level(bmap,
233 bdescs[i].bd_offset,
234 bdescs[i].bd_level + 1,
235 &bdescs[i].bd_blocknr);
236 if (ret < 0) {
237 if (ret != -ENOENT) {
238 up_read(&nilfs->ns_segctor_sem);
239 return ret;
241 bdescs[i].bd_blocknr = 0;
244 up_read(&nilfs->ns_segctor_sem);
245 return nmembs;
248 static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
249 unsigned int cmd, void __user *argp)
251 struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
252 struct nilfs_argv argv;
253 int ret;
255 if (copy_from_user(&argv, argp, sizeof(argv)))
256 return -EFAULT;
258 if (argv.v_size != sizeof(struct nilfs_bdesc))
259 return -EINVAL;
261 ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
262 nilfs_ioctl_do_get_bdescs);
263 if (ret < 0)
264 return ret;
266 if (copy_to_user(argp, &argv, sizeof(argv)))
267 ret = -EFAULT;
268 return ret;
271 static int nilfs_ioctl_move_inode_block(struct inode *inode,
272 struct nilfs_vdesc *vdesc,
273 struct list_head *buffers)
275 struct buffer_head *bh;
276 int ret;
278 if (vdesc->vd_flags == 0)
279 ret = nilfs_gccache_submit_read_data(
280 inode, vdesc->vd_offset, vdesc->vd_blocknr,
281 vdesc->vd_vblocknr, &bh);
282 else
283 ret = nilfs_gccache_submit_read_node(
284 inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);
286 if (unlikely(ret < 0)) {
287 if (ret == -ENOENT)
288 printk(KERN_CRIT
289 "%s: invalid virtual block address (%s): "
290 "ino=%llu, cno=%llu, offset=%llu, "
291 "blocknr=%llu, vblocknr=%llu\n",
292 __func__, vdesc->vd_flags ? "node" : "data",
293 (unsigned long long)vdesc->vd_ino,
294 (unsigned long long)vdesc->vd_cno,
295 (unsigned long long)vdesc->vd_offset,
296 (unsigned long long)vdesc->vd_blocknr,
297 (unsigned long long)vdesc->vd_vblocknr);
298 return ret;
300 bh->b_private = vdesc;
301 list_add_tail(&bh->b_assoc_buffers, buffers);
302 return 0;
305 static int nilfs_ioctl_move_blocks(struct the_nilfs *nilfs,
306 struct nilfs_argv *argv, void *buf)
308 size_t nmembs = argv->v_nmembs;
309 struct inode *inode;
310 struct nilfs_vdesc *vdesc;
311 struct buffer_head *bh, *n;
312 LIST_HEAD(buffers);
313 ino_t ino;
314 __u64 cno;
315 int i, ret;
317 for (i = 0, vdesc = buf; i < nmembs; ) {
318 ino = vdesc->vd_ino;
319 cno = vdesc->vd_cno;
320 inode = nilfs_gc_iget(nilfs, ino, cno);
321 if (unlikely(inode == NULL)) {
322 ret = -ENOMEM;
323 goto failed;
325 do {
326 ret = nilfs_ioctl_move_inode_block(inode, vdesc,
327 &buffers);
328 if (unlikely(ret < 0))
329 goto failed;
330 vdesc++;
331 } while (++i < nmembs &&
332 vdesc->vd_ino == ino && vdesc->vd_cno == cno);
335 list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
336 ret = nilfs_gccache_wait_and_mark_dirty(bh);
337 if (unlikely(ret < 0)) {
338 if (ret == -EEXIST) {
339 vdesc = bh->b_private;
340 printk(KERN_CRIT
341 "%s: conflicting %s buffer: "
342 "ino=%llu, cno=%llu, offset=%llu, "
343 "blocknr=%llu, vblocknr=%llu\n",
344 __func__,
345 vdesc->vd_flags ? "node" : "data",
346 (unsigned long long)vdesc->vd_ino,
347 (unsigned long long)vdesc->vd_cno,
348 (unsigned long long)vdesc->vd_offset,
349 (unsigned long long)vdesc->vd_blocknr,
350 (unsigned long long)vdesc->vd_vblocknr);
352 goto failed;
354 list_del_init(&bh->b_assoc_buffers);
355 bh->b_private = NULL;
356 brelse(bh);
358 return nmembs;
360 failed:
361 list_for_each_entry_safe(bh, n, &buffers, b_assoc_buffers) {
362 list_del_init(&bh->b_assoc_buffers);
363 bh->b_private = NULL;
364 brelse(bh);
366 return ret;
369 static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
370 struct nilfs_argv *argv, void *buf)
372 size_t nmembs = argv->v_nmembs;
373 struct inode *cpfile = nilfs->ns_cpfile;
374 struct nilfs_period *periods = buf;
375 int ret, i;
377 for (i = 0; i < nmembs; i++) {
378 ret = nilfs_cpfile_delete_checkpoints(
379 cpfile, periods[i].p_start, periods[i].p_end);
380 if (ret < 0)
381 return ret;
383 return nmembs;
386 static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
387 struct nilfs_argv *argv, void *buf)
389 size_t nmembs = argv->v_nmembs;
390 int ret;
392 ret = nilfs_dat_freev(nilfs_dat_inode(nilfs), buf, nmembs);
394 return (ret < 0) ? ret : nmembs;
397 static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
398 struct nilfs_argv *argv, void *buf)
400 size_t nmembs = argv->v_nmembs;
401 struct inode *dat = nilfs_dat_inode(nilfs);
402 struct nilfs_bmap *bmap = NILFS_I(dat)->i_bmap;
403 struct nilfs_bdesc *bdescs = buf;
404 int ret, i;
406 for (i = 0; i < nmembs; i++) {
407 /* XXX: use macro or inline func to check liveness */
408 ret = nilfs_bmap_lookup_at_level(bmap,
409 bdescs[i].bd_offset,
410 bdescs[i].bd_level + 1,
411 &bdescs[i].bd_blocknr);
412 if (ret < 0) {
413 if (ret != -ENOENT)
414 return ret;
415 bdescs[i].bd_blocknr = 0;
417 if (bdescs[i].bd_blocknr != bdescs[i].bd_oblocknr)
418 /* skip dead block */
419 continue;
420 if (bdescs[i].bd_level == 0) {
421 ret = nilfs_mdt_mark_block_dirty(dat,
422 bdescs[i].bd_offset);
423 if (ret < 0) {
424 WARN_ON(ret == -ENOENT);
425 return ret;
427 } else {
428 ret = nilfs_bmap_mark(bmap, bdescs[i].bd_offset,
429 bdescs[i].bd_level);
430 if (ret < 0) {
431 WARN_ON(ret == -ENOENT);
432 return ret;
436 return nmembs;
439 int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
440 struct nilfs_argv *argv, void **kbufs)
442 const char *msg;
443 int ret;
445 ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], kbufs[1]);
446 if (ret < 0) {
448 * can safely abort because checkpoints can be removed
449 * independently.
451 msg = "cannot delete checkpoints";
452 goto failed;
454 ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], kbufs[2]);
455 if (ret < 0) {
457 * can safely abort because DAT file is updated atomically
458 * using a copy-on-write technique.
460 msg = "cannot delete virtual blocks from DAT file";
461 goto failed;
463 ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], kbufs[3]);
464 if (ret < 0) {
466 * can safely abort because the operation is nondestructive.
468 msg = "cannot mark copying blocks dirty";
469 goto failed;
471 return 0;
473 failed:
474 nilfs_remove_all_gcinode(nilfs);
475 printk(KERN_ERR "NILFS: GC failed during preparation: %s: err=%d\n",
476 msg, ret);
477 return ret;
480 static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
481 unsigned int cmd, void __user *argp)
483 struct nilfs_argv argv[5];
484 const static size_t argsz[5] = {
485 sizeof(struct nilfs_vdesc),
486 sizeof(struct nilfs_period),
487 sizeof(__u64),
488 sizeof(struct nilfs_bdesc),
489 sizeof(__u64),
491 void __user *base;
492 void *kbufs[5];
493 struct the_nilfs *nilfs;
494 size_t len, nsegs;
495 int n, ret;
497 if (!capable(CAP_SYS_ADMIN))
498 return -EPERM;
500 if (copy_from_user(argv, argp, sizeof(argv)))
501 return -EFAULT;
503 nsegs = argv[4].v_nmembs;
504 if (argv[4].v_size != argsz[4])
505 return -EINVAL;
507 * argv[4] points to segment numbers this ioctl cleans. We
508 * use kmalloc() for its buffer because memory used for the
509 * segment numbers is enough small.
511 kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base,
512 nsegs * sizeof(__u64));
513 if (IS_ERR(kbufs[4]))
514 return PTR_ERR(kbufs[4]);
516 nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
518 for (n = 0; n < 4; n++) {
519 ret = -EINVAL;
520 if (argv[n].v_size != argsz[n])
521 goto out_free;
523 if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
524 goto out_free;
526 len = argv[n].v_size * argv[n].v_nmembs;
527 base = (void __user *)(unsigned long)argv[n].v_base;
528 if (len == 0) {
529 kbufs[n] = NULL;
530 continue;
533 kbufs[n] = vmalloc(len);
534 if (!kbufs[n]) {
535 ret = -ENOMEM;
536 goto out_free;
538 if (copy_from_user(kbufs[n], base, len)) {
539 ret = -EFAULT;
540 vfree(kbufs[n]);
541 goto out_free;
546 * nilfs_ioctl_move_blocks() will call nilfs_gc_iget(),
547 * which will operates an inode list without blocking.
548 * To protect the list from concurrent operations,
549 * nilfs_ioctl_move_blocks should be atomic operation.
551 if (test_and_set_bit(THE_NILFS_GC_RUNNING, &nilfs->ns_flags)) {
552 ret = -EBUSY;
553 goto out_free;
556 ret = nilfs_ioctl_move_blocks(nilfs, &argv[0], kbufs[0]);
557 if (ret < 0)
558 printk(KERN_ERR "NILFS: GC failed during preparation: "
559 "cannot read source blocks: err=%d\n", ret);
560 else
561 ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);
563 clear_nilfs_gc_running(nilfs);
565 out_free:
566 while (--n >= 0)
567 vfree(kbufs[n]);
568 kfree(kbufs[4]);
569 return ret;
572 static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
573 unsigned int cmd, void __user *argp)
575 __u64 cno;
576 int ret;
578 ret = nilfs_construct_segment(inode->i_sb);
579 if (ret < 0)
580 return ret;
582 if (argp != NULL) {
583 cno = NILFS_SB(inode->i_sb)->s_nilfs->ns_cno - 1;
584 if (copy_to_user(argp, &cno, sizeof(cno)))
585 return -EFAULT;
587 return 0;
590 static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
591 unsigned int cmd, void __user *argp,
592 size_t membsz,
593 ssize_t (*dofunc)(struct the_nilfs *,
594 __u64 *, int,
595 void *, size_t, size_t))
598 struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
599 struct nilfs_argv argv;
600 int ret;
602 if (copy_from_user(&argv, argp, sizeof(argv)))
603 return -EFAULT;
605 if (argv.v_size < membsz)
606 return -EINVAL;
608 ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
609 if (ret < 0)
610 return ret;
612 if (copy_to_user(argp, &argv, sizeof(argv)))
613 ret = -EFAULT;
614 return ret;
617 long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
619 struct inode *inode = filp->f_dentry->d_inode;
620 void __user *argp = (void * __user *)arg;
622 switch (cmd) {
623 case NILFS_IOCTL_CHANGE_CPMODE:
624 return nilfs_ioctl_change_cpmode(inode, filp, cmd, argp);
625 case NILFS_IOCTL_DELETE_CHECKPOINT:
626 return nilfs_ioctl_delete_checkpoint(inode, filp, cmd, argp);
627 case NILFS_IOCTL_GET_CPINFO:
628 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
629 sizeof(struct nilfs_cpinfo),
630 nilfs_ioctl_do_get_cpinfo);
631 case NILFS_IOCTL_GET_CPSTAT:
632 return nilfs_ioctl_get_cpstat(inode, filp, cmd, argp);
633 case NILFS_IOCTL_GET_SUINFO:
634 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
635 sizeof(struct nilfs_suinfo),
636 nilfs_ioctl_do_get_suinfo);
637 case NILFS_IOCTL_GET_SUSTAT:
638 return nilfs_ioctl_get_sustat(inode, filp, cmd, argp);
639 case NILFS_IOCTL_GET_VINFO:
640 return nilfs_ioctl_get_info(inode, filp, cmd, argp,
641 sizeof(struct nilfs_vinfo),
642 nilfs_ioctl_do_get_vinfo);
643 case NILFS_IOCTL_GET_BDESCS:
644 return nilfs_ioctl_get_bdescs(inode, filp, cmd, argp);
645 case NILFS_IOCTL_CLEAN_SEGMENTS:
646 return nilfs_ioctl_clean_segments(inode, filp, cmd, argp);
647 case NILFS_IOCTL_SYNC:
648 return nilfs_ioctl_sync(inode, filp, cmd, argp);
649 default:
650 return -ENOTTY;