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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/**
2 * mft.c - NTFS kernel mft record operations. Part of the Linux-NTFS project.
3 *
Anton Altaparmakov78af34f2006-02-24 10:32:33 +00004 * Copyright (c) 2001-2006 Anton Altaparmakov
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * Copyright (c) 2002 Richard Russon
6 *
7 * This program/include file is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as published
9 * by the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program/include file is distributed in the hope that it will be
13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program (in the main directory of the Linux-NTFS
19 * distribution in the file COPYING); if not, write to the Free Software
20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
22
23#include <linux/buffer_head.h>
24#include <linux/swap.h>
25
26#include "attrib.h"
27#include "aops.h"
28#include "bitmap.h"
29#include "debug.h"
30#include "dir.h"
31#include "lcnalloc.h"
32#include "malloc.h"
33#include "mft.h"
34#include "ntfs.h"
35
36/**
37 * map_mft_record_page - map the page in which a specific mft record resides
38 * @ni: ntfs inode whose mft record page to map
39 *
40 * This maps the page in which the mft record of the ntfs inode @ni is situated
41 * and returns a pointer to the mft record within the mapped page.
42 *
43 * Return value needs to be checked with IS_ERR() and if that is true PTR_ERR()
44 * contains the negative error code returned.
45 */
46static inline MFT_RECORD *map_mft_record_page(ntfs_inode *ni)
47{
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000048 loff_t i_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 ntfs_volume *vol = ni->vol;
50 struct inode *mft_vi = vol->mft_ino;
51 struct page *page;
Anton Altaparmakov69b41e32005-10-04 14:01:14 +010052 unsigned long index, end_index;
53 unsigned ofs;
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55 BUG_ON(ni->page);
56 /*
57 * The index into the page cache and the offset within the page cache
58 * page of the wanted mft record. FIXME: We need to check for
59 * overflowing the unsigned long, but I don't think we would ever get
60 * here if the volume was that big...
61 */
Anton Altaparmakovc394e452005-10-04 13:08:53 +010062 index = (u64)ni->mft_no << vol->mft_record_size_bits >>
63 PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 ofs = (ni->mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
65
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000066 i_size = i_size_read(mft_vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 /* The maximum valid index into the page cache for $MFT's data. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000068 end_index = i_size >> PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
70 /* If the wanted index is out of bounds the mft record doesn't exist. */
71 if (unlikely(index >= end_index)) {
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +000072 if (index > end_index || (i_size & ~PAGE_CACHE_MASK) < ofs +
73 vol->mft_record_size) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 page = ERR_PTR(-ENOENT);
75 ntfs_error(vol->sb, "Attemt to read mft record 0x%lx, "
76 "which is beyond the end of the mft. "
77 "This is probably a bug in the ntfs "
78 "driver.", ni->mft_no);
79 goto err_out;
80 }
81 }
82 /* Read, map, and pin the page. */
83 page = ntfs_map_page(mft_vi->i_mapping, index);
84 if (likely(!IS_ERR(page))) {
85 /* Catch multi sector transfer fixup errors. */
86 if (likely(ntfs_is_mft_recordp((le32*)(page_address(page) +
87 ofs)))) {
88 ni->page = page;
89 ni->page_ofs = ofs;
90 return page_address(page) + ofs;
91 }
92 ntfs_error(vol->sb, "Mft record 0x%lx is corrupt. "
93 "Run chkdsk.", ni->mft_no);
94 ntfs_unmap_page(page);
95 page = ERR_PTR(-EIO);
96 }
97err_out:
98 ni->page = NULL;
99 ni->page_ofs = 0;
100 return (void*)page;
101}
102
103/**
104 * map_mft_record - map, pin and lock an mft record
105 * @ni: ntfs inode whose MFT record to map
106 *
107 * First, take the mrec_lock semaphore. We might now be sleeping, while waiting
108 * for the semaphore if it was already locked by someone else.
109 *
110 * The page of the record is mapped using map_mft_record_page() before being
111 * returned to the caller.
112 *
113 * This in turn uses ntfs_map_page() to get the page containing the wanted mft
114 * record (it in turn calls read_cache_page() which reads it in from disk if
115 * necessary, increments the use count on the page so that it cannot disappear
116 * under us and returns a reference to the page cache page).
117 *
118 * If read_cache_page() invokes ntfs_readpage() to load the page from disk, it
119 * sets PG_locked and clears PG_uptodate on the page. Once I/O has completed
120 * and the post-read mst fixups on each mft record in the page have been
121 * performed, the page gets PG_uptodate set and PG_locked cleared (this is done
122 * in our asynchronous I/O completion handler end_buffer_read_mft_async()).
123 * ntfs_map_page() waits for PG_locked to become clear and checks if
124 * PG_uptodate is set and returns an error code if not. This provides
125 * sufficient protection against races when reading/using the page.
126 *
127 * However there is the write mapping to think about. Doing the above described
128 * checking here will be fine, because when initiating the write we will set
129 * PG_locked and clear PG_uptodate making sure nobody is touching the page
130 * contents. Doing the locking this way means that the commit to disk code in
131 * the page cache code paths is automatically sufficiently locked with us as
132 * we will not touch a page that has been locked or is not uptodate. The only
133 * locking problem then is them locking the page while we are accessing it.
134 *
135 * So that code will end up having to own the mrec_lock of all mft
136 * records/inodes present in the page before I/O can proceed. In that case we
137 * wouldn't need to bother with PG_locked and PG_uptodate as nobody will be
138 * accessing anything without owning the mrec_lock semaphore. But we do need
139 * to use them because of the read_cache_page() invocation and the code becomes
140 * so much simpler this way that it is well worth it.
141 *
142 * The mft record is now ours and we return a pointer to it. You need to check
143 * the returned pointer with IS_ERR() and if that is true, PTR_ERR() will return
144 * the error code.
145 *
146 * NOTE: Caller is responsible for setting the mft record dirty before calling
147 * unmap_mft_record(). This is obviously only necessary if the caller really
148 * modified the mft record...
149 * Q: Do we want to recycle one of the VFS inode state bits instead?
150 * A: No, the inode ones mean we want to change the mft record, not we want to
151 * write it out.
152 */
153MFT_RECORD *map_mft_record(ntfs_inode *ni)
154{
155 MFT_RECORD *m;
156
157 ntfs_debug("Entering for mft_no 0x%lx.", ni->mft_no);
158
159 /* Make sure the ntfs inode doesn't go away. */
160 atomic_inc(&ni->count);
161
162 /* Serialize access to this mft record. */
163 down(&ni->mrec_lock);
164
165 m = map_mft_record_page(ni);
166 if (likely(!IS_ERR(m)))
167 return m;
168
169 up(&ni->mrec_lock);
170 atomic_dec(&ni->count);
171 ntfs_error(ni->vol->sb, "Failed with error code %lu.", -PTR_ERR(m));
172 return m;
173}
174
175/**
176 * unmap_mft_record_page - unmap the page in which a specific mft record resides
177 * @ni: ntfs inode whose mft record page to unmap
178 *
179 * This unmaps the page in which the mft record of the ntfs inode @ni is
180 * situated and returns. This is a NOOP if highmem is not configured.
181 *
182 * The unmap happens via ntfs_unmap_page() which in turn decrements the use
183 * count on the page thus releasing it from the pinned state.
184 *
185 * We do not actually unmap the page from memory of course, as that will be
186 * done by the page cache code itself when memory pressure increases or
187 * whatever.
188 */
189static inline void unmap_mft_record_page(ntfs_inode *ni)
190{
191 BUG_ON(!ni->page);
192
193 // TODO: If dirty, blah...
194 ntfs_unmap_page(ni->page);
195 ni->page = NULL;
196 ni->page_ofs = 0;
197 return;
198}
199
200/**
201 * unmap_mft_record - release a mapped mft record
202 * @ni: ntfs inode whose MFT record to unmap
203 *
204 * We release the page mapping and the mrec_lock mutex which unmaps the mft
205 * record and releases it for others to get hold of. We also release the ntfs
206 * inode by decrementing the ntfs inode reference count.
207 *
208 * NOTE: If caller has modified the mft record, it is imperative to set the mft
209 * record dirty BEFORE calling unmap_mft_record().
210 */
211void unmap_mft_record(ntfs_inode *ni)
212{
213 struct page *page = ni->page;
214
215 BUG_ON(!page);
216
217 ntfs_debug("Entering for mft_no 0x%lx.", ni->mft_no);
218
219 unmap_mft_record_page(ni);
220 up(&ni->mrec_lock);
221 atomic_dec(&ni->count);
222 /*
223 * If pure ntfs_inode, i.e. no vfs inode attached, we leave it to
224 * ntfs_clear_extent_inode() in the extent inode case, and to the
225 * caller in the non-extent, yet pure ntfs inode case, to do the actual
226 * tear down of all structures and freeing of all allocated memory.
227 */
228 return;
229}
230
231/**
232 * map_extent_mft_record - load an extent inode and attach it to its base
233 * @base_ni: base ntfs inode
234 * @mref: mft reference of the extent inode to load
235 * @ntfs_ino: on successful return, pointer to the ntfs_inode structure
236 *
237 * Load the extent mft record @mref and attach it to its base inode @base_ni.
238 * Return the mapped extent mft record if IS_ERR(result) is false. Otherwise
239 * PTR_ERR(result) gives the negative error code.
240 *
241 * On successful return, @ntfs_ino contains a pointer to the ntfs_inode
242 * structure of the mapped extent inode.
243 */
244MFT_RECORD *map_extent_mft_record(ntfs_inode *base_ni, MFT_REF mref,
245 ntfs_inode **ntfs_ino)
246{
247 MFT_RECORD *m;
248 ntfs_inode *ni = NULL;
249 ntfs_inode **extent_nis = NULL;
250 int i;
251 unsigned long mft_no = MREF(mref);
252 u16 seq_no = MSEQNO(mref);
253 BOOL destroy_ni = FALSE;
254
255 ntfs_debug("Mapping extent mft record 0x%lx (base mft record 0x%lx).",
256 mft_no, base_ni->mft_no);
257 /* Make sure the base ntfs inode doesn't go away. */
258 atomic_inc(&base_ni->count);
259 /*
260 * Check if this extent inode has already been added to the base inode,
261 * in which case just return it. If not found, add it to the base
262 * inode before returning it.
263 */
264 down(&base_ni->extent_lock);
265 if (base_ni->nr_extents > 0) {
266 extent_nis = base_ni->ext.extent_ntfs_inos;
267 for (i = 0; i < base_ni->nr_extents; i++) {
268 if (mft_no != extent_nis[i]->mft_no)
269 continue;
270 ni = extent_nis[i];
271 /* Make sure the ntfs inode doesn't go away. */
272 atomic_inc(&ni->count);
273 break;
274 }
275 }
276 if (likely(ni != NULL)) {
277 up(&base_ni->extent_lock);
278 atomic_dec(&base_ni->count);
279 /* We found the record; just have to map and return it. */
280 m = map_mft_record(ni);
281 /* map_mft_record() has incremented this on success. */
282 atomic_dec(&ni->count);
283 if (likely(!IS_ERR(m))) {
284 /* Verify the sequence number. */
285 if (likely(le16_to_cpu(m->sequence_number) == seq_no)) {
286 ntfs_debug("Done 1.");
287 *ntfs_ino = ni;
288 return m;
289 }
290 unmap_mft_record(ni);
291 ntfs_error(base_ni->vol->sb, "Found stale extent mft "
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000292 "reference! Corrupt filesystem. "
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 "Run chkdsk.");
294 return ERR_PTR(-EIO);
295 }
296map_err_out:
297 ntfs_error(base_ni->vol->sb, "Failed to map extent "
298 "mft record, error code %ld.", -PTR_ERR(m));
299 return m;
300 }
301 /* Record wasn't there. Get a new ntfs inode and initialize it. */
302 ni = ntfs_new_extent_inode(base_ni->vol->sb, mft_no);
303 if (unlikely(!ni)) {
304 up(&base_ni->extent_lock);
305 atomic_dec(&base_ni->count);
306 return ERR_PTR(-ENOMEM);
307 }
308 ni->vol = base_ni->vol;
309 ni->seq_no = seq_no;
310 ni->nr_extents = -1;
311 ni->ext.base_ntfs_ino = base_ni;
312 /* Now map the record. */
313 m = map_mft_record(ni);
314 if (IS_ERR(m)) {
315 up(&base_ni->extent_lock);
316 atomic_dec(&base_ni->count);
317 ntfs_clear_extent_inode(ni);
318 goto map_err_out;
319 }
320 /* Verify the sequence number if it is present. */
321 if (seq_no && (le16_to_cpu(m->sequence_number) != seq_no)) {
322 ntfs_error(base_ni->vol->sb, "Found stale extent mft "
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +0000323 "reference! Corrupt filesystem. Run chkdsk.");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 destroy_ni = TRUE;
325 m = ERR_PTR(-EIO);
326 goto unm_err_out;
327 }
328 /* Attach extent inode to base inode, reallocating memory if needed. */
329 if (!(base_ni->nr_extents & 3)) {
330 ntfs_inode **tmp;
331 int new_size = (base_ni->nr_extents + 4) * sizeof(ntfs_inode *);
332
333 tmp = (ntfs_inode **)kmalloc(new_size, GFP_NOFS);
334 if (unlikely(!tmp)) {
335 ntfs_error(base_ni->vol->sb, "Failed to allocate "
336 "internal buffer.");
337 destroy_ni = TRUE;
338 m = ERR_PTR(-ENOMEM);
339 goto unm_err_out;
340 }
341 if (base_ni->nr_extents) {
342 BUG_ON(!base_ni->ext.extent_ntfs_inos);
343 memcpy(tmp, base_ni->ext.extent_ntfs_inos, new_size -
344 4 * sizeof(ntfs_inode *));
345 kfree(base_ni->ext.extent_ntfs_inos);
346 }
347 base_ni->ext.extent_ntfs_inos = tmp;
348 }
349 base_ni->ext.extent_ntfs_inos[base_ni->nr_extents++] = ni;
350 up(&base_ni->extent_lock);
351 atomic_dec(&base_ni->count);
352 ntfs_debug("Done 2.");
353 *ntfs_ino = ni;
354 return m;
355unm_err_out:
356 unmap_mft_record(ni);
357 up(&base_ni->extent_lock);
358 atomic_dec(&base_ni->count);
359 /*
360 * If the extent inode was not attached to the base inode we need to
361 * release it or we will leak memory.
362 */
363 if (destroy_ni)
364 ntfs_clear_extent_inode(ni);
365 return m;
366}
367
368#ifdef NTFS_RW
369
370/**
371 * __mark_mft_record_dirty - set the mft record and the page containing it dirty
372 * @ni: ntfs inode describing the mapped mft record
373 *
374 * Internal function. Users should call mark_mft_record_dirty() instead.
375 *
376 * Set the mapped (extent) mft record of the (base or extent) ntfs inode @ni,
377 * as well as the page containing the mft record, dirty. Also, mark the base
378 * vfs inode dirty. This ensures that any changes to the mft record are
379 * written out to disk.
380 *
381 * NOTE: We only set I_DIRTY_SYNC and I_DIRTY_DATASYNC (and not I_DIRTY_PAGES)
382 * on the base vfs inode, because even though file data may have been modified,
383 * it is dirty in the inode meta data rather than the data page cache of the
384 * inode, and thus there are no data pages that need writing out. Therefore, a
385 * full mark_inode_dirty() is overkill. A mark_inode_dirty_sync(), on the
386 * other hand, is not sufficient, because I_DIRTY_DATASYNC needs to be set to
387 * ensure ->write_inode is called from generic_osync_inode() and this needs to
388 * happen or the file data would not necessarily hit the device synchronously,
389 * even though the vfs inode has the O_SYNC flag set. Also, I_DIRTY_DATASYNC
390 * simply "feels" better than just I_DIRTY_SYNC, since the file data has not
391 * actually hit the block device yet, which is not what I_DIRTY_SYNC on its own
392 * would suggest.
393 */
394void __mark_mft_record_dirty(ntfs_inode *ni)
395{
396 ntfs_inode *base_ni;
397
398 ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
399 BUG_ON(NInoAttr(ni));
400 mark_ntfs_record_dirty(ni->page, ni->page_ofs);
401 /* Determine the base vfs inode and mark it dirty, too. */
402 down(&ni->extent_lock);
403 if (likely(ni->nr_extents >= 0))
404 base_ni = ni;
405 else
406 base_ni = ni->ext.base_ntfs_ino;
407 up(&ni->extent_lock);
408 __mark_inode_dirty(VFS_I(base_ni), I_DIRTY_SYNC | I_DIRTY_DATASYNC);
409}
410
411static const char *ntfs_please_email = "Please email "
412 "linux-ntfs-dev@lists.sourceforge.net and say that you saw "
413 "this message. Thank you.";
414
415/**
416 * ntfs_sync_mft_mirror_umount - synchronise an mft record to the mft mirror
417 * @vol: ntfs volume on which the mft record to synchronize resides
418 * @mft_no: mft record number of mft record to synchronize
419 * @m: mapped, mst protected (extent) mft record to synchronize
420 *
421 * Write the mapped, mst protected (extent) mft record @m with mft record
422 * number @mft_no to the mft mirror ($MFTMirr) of the ntfs volume @vol,
423 * bypassing the page cache and the $MFTMirr inode itself.
424 *
425 * This function is only for use at umount time when the mft mirror inode has
426 * already been disposed off. We BUG() if we are called while the mft mirror
427 * inode is still attached to the volume.
428 *
429 * On success return 0. On error return -errno.
430 *
431 * NOTE: This function is not implemented yet as I am not convinced it can
432 * actually be triggered considering the sequence of commits we do in super.c::
433 * ntfs_put_super(). But just in case we provide this place holder as the
434 * alternative would be either to BUG() or to get a NULL pointer dereference
435 * and Oops.
436 */
437static int ntfs_sync_mft_mirror_umount(ntfs_volume *vol,
438 const unsigned long mft_no, MFT_RECORD *m)
439{
440 BUG_ON(vol->mftmirr_ino);
441 ntfs_error(vol->sb, "Umount time mft mirror syncing is not "
442 "implemented yet. %s", ntfs_please_email);
443 return -EOPNOTSUPP;
444}
445
446/**
447 * ntfs_sync_mft_mirror - synchronize an mft record to the mft mirror
448 * @vol: ntfs volume on which the mft record to synchronize resides
449 * @mft_no: mft record number of mft record to synchronize
450 * @m: mapped, mst protected (extent) mft record to synchronize
451 * @sync: if true, wait for i/o completion
452 *
453 * Write the mapped, mst protected (extent) mft record @m with mft record
454 * number @mft_no to the mft mirror ($MFTMirr) of the ntfs volume @vol.
455 *
456 * On success return 0. On error return -errno and set the volume errors flag
457 * in the ntfs volume @vol.
458 *
459 * NOTE: We always perform synchronous i/o and ignore the @sync parameter.
460 *
461 * TODO: If @sync is false, want to do truly asynchronous i/o, i.e. just
462 * schedule i/o via ->writepage or do it via kntfsd or whatever.
463 */
464int ntfs_sync_mft_mirror(ntfs_volume *vol, const unsigned long mft_no,
465 MFT_RECORD *m, int sync)
466{
467 struct page *page;
468 unsigned int blocksize = vol->sb->s_blocksize;
469 int max_bhs = vol->mft_record_size / blocksize;
470 struct buffer_head *bhs[max_bhs];
471 struct buffer_head *bh, *head;
472 u8 *kmirr;
473 runlist_element *rl;
474 unsigned int block_start, block_end, m_start, m_end, page_ofs;
475 int i_bhs, nr_bhs, err = 0;
Anton Altaparmakov78af34f2006-02-24 10:32:33 +0000476 unsigned char blocksize_bits = vol->sb->s_blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700477
478 ntfs_debug("Entering for inode 0x%lx.", mft_no);
479 BUG_ON(!max_bhs);
480 if (unlikely(!vol->mftmirr_ino)) {
481 /* This could happen during umount... */
482 err = ntfs_sync_mft_mirror_umount(vol, mft_no, m);
483 if (likely(!err))
484 return err;
485 goto err_out;
486 }
487 /* Get the page containing the mirror copy of the mft record @m. */
488 page = ntfs_map_page(vol->mftmirr_ino->i_mapping, mft_no >>
489 (PAGE_CACHE_SHIFT - vol->mft_record_size_bits));
490 if (IS_ERR(page)) {
491 ntfs_error(vol->sb, "Failed to map mft mirror page.");
492 err = PTR_ERR(page);
493 goto err_out;
494 }
495 lock_page(page);
496 BUG_ON(!PageUptodate(page));
497 ClearPageUptodate(page);
498 /* Offset of the mft mirror record inside the page. */
499 page_ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
500 /* The address in the page of the mirror copy of the mft record @m. */
501 kmirr = page_address(page) + page_ofs;
502 /* Copy the mst protected mft record to the mirror. */
503 memcpy(kmirr, m, vol->mft_record_size);
504 /* Create uptodate buffers if not present. */
505 if (unlikely(!page_has_buffers(page))) {
506 struct buffer_head *tail;
507
508 bh = head = alloc_page_buffers(page, blocksize, 1);
509 do {
510 set_buffer_uptodate(bh);
511 tail = bh;
512 bh = bh->b_this_page;
513 } while (bh);
514 tail->b_this_page = head;
515 attach_page_buffers(page, head);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 }
517 bh = head = page_buffers(page);
518 BUG_ON(!bh);
519 rl = NULL;
520 nr_bhs = 0;
521 block_start = 0;
522 m_start = kmirr - (u8*)page_address(page);
523 m_end = m_start + vol->mft_record_size;
524 do {
525 block_end = block_start + blocksize;
526 /* If the buffer is outside the mft record, skip it. */
527 if (block_end <= m_start)
528 continue;
529 if (unlikely(block_start >= m_end))
530 break;
531 /* Need to map the buffer if it is not mapped already. */
532 if (unlikely(!buffer_mapped(bh))) {
533 VCN vcn;
534 LCN lcn;
535 unsigned int vcn_ofs;
536
Anton Altaparmakove74589a2005-08-16 16:38:28 +0100537 bh->b_bdev = vol->sb->s_bdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 /* Obtain the vcn and offset of the current block. */
539 vcn = ((VCN)mft_no << vol->mft_record_size_bits) +
540 (block_start - m_start);
541 vcn_ofs = vcn & vol->cluster_size_mask;
542 vcn >>= vol->cluster_size_bits;
543 if (!rl) {
544 down_read(&NTFS_I(vol->mftmirr_ino)->
545 runlist.lock);
546 rl = NTFS_I(vol->mftmirr_ino)->runlist.rl;
547 /*
548 * $MFTMirr always has the whole of its runlist
549 * in memory.
550 */
551 BUG_ON(!rl);
552 }
553 /* Seek to element containing target vcn. */
554 while (rl->length && rl[1].vcn <= vcn)
555 rl++;
556 lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
557 /* For $MFTMirr, only lcn >= 0 is a successful remap. */
558 if (likely(lcn >= 0)) {
559 /* Setup buffer head to correct block. */
560 bh->b_blocknr = ((lcn <<
561 vol->cluster_size_bits) +
562 vcn_ofs) >> blocksize_bits;
563 set_buffer_mapped(bh);
564 } else {
565 bh->b_blocknr = -1;
566 ntfs_error(vol->sb, "Cannot write mft mirror "
567 "record 0x%lx because its "
568 "location on disk could not "
569 "be determined (error code "
570 "%lli).", mft_no,
571 (long long)lcn);
572 err = -EIO;
573 }
574 }
575 BUG_ON(!buffer_uptodate(bh));
576 BUG_ON(!nr_bhs && (m_start != block_start));
577 BUG_ON(nr_bhs >= max_bhs);
578 bhs[nr_bhs++] = bh;
579 BUG_ON((nr_bhs >= max_bhs) && (m_end != block_end));
580 } while (block_start = block_end, (bh = bh->b_this_page) != head);
581 if (unlikely(rl))
582 up_read(&NTFS_I(vol->mftmirr_ino)->runlist.lock);
583 if (likely(!err)) {
584 /* Lock buffers and start synchronous write i/o on them. */
585 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
586 struct buffer_head *tbh = bhs[i_bhs];
587
588 if (unlikely(test_set_buffer_locked(tbh)))
589 BUG();
590 BUG_ON(!buffer_uptodate(tbh));
591 clear_buffer_dirty(tbh);
592 get_bh(tbh);
593 tbh->b_end_io = end_buffer_write_sync;
594 submit_bh(WRITE, tbh);
595 }
596 /* Wait on i/o completion of buffers. */
597 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
598 struct buffer_head *tbh = bhs[i_bhs];
599
600 wait_on_buffer(tbh);
601 if (unlikely(!buffer_uptodate(tbh))) {
602 err = -EIO;
603 /*
604 * Set the buffer uptodate so the page and
605 * buffer states do not become out of sync.
606 */
607 set_buffer_uptodate(tbh);
608 }
609 }
610 } else /* if (unlikely(err)) */ {
611 /* Clean the buffers. */
612 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++)
613 clear_buffer_dirty(bhs[i_bhs]);
614 }
615 /* Current state: all buffers are clean, unlocked, and uptodate. */
616 /* Remove the mst protection fixups again. */
617 post_write_mst_fixup((NTFS_RECORD*)kmirr);
618 flush_dcache_page(page);
619 SetPageUptodate(page);
620 unlock_page(page);
621 ntfs_unmap_page(page);
622 if (likely(!err)) {
623 ntfs_debug("Done.");
624 } else {
625 ntfs_error(vol->sb, "I/O error while writing mft mirror "
626 "record 0x%lx!", mft_no);
627err_out:
628 ntfs_error(vol->sb, "Failed to synchronize $MFTMirr (error "
629 "code %i). Volume will be left marked dirty "
630 "on umount. Run ntfsfix on the partition "
631 "after umounting to correct this.", -err);
632 NVolSetErrors(vol);
633 }
634 return err;
635}
636
637/**
638 * write_mft_record_nolock - write out a mapped (extent) mft record
639 * @ni: ntfs inode describing the mapped (extent) mft record
640 * @m: mapped (extent) mft record to write
641 * @sync: if true, wait for i/o completion
642 *
643 * Write the mapped (extent) mft record @m described by the (regular or extent)
644 * ntfs inode @ni to backing store. If the mft record @m has a counterpart in
645 * the mft mirror, that is also updated.
646 *
647 * We only write the mft record if the ntfs inode @ni is dirty and the first
648 * buffer belonging to its mft record is dirty, too. We ignore the dirty state
649 * of subsequent buffers because we could have raced with
650 * fs/ntfs/aops.c::mark_ntfs_record_dirty().
651 *
652 * On success, clean the mft record and return 0. On error, leave the mft
653 * record dirty and return -errno. The caller should call make_bad_inode() on
654 * the base inode to ensure no more access happens to this inode. We do not do
655 * it here as the caller may want to finish writing other extent mft records
656 * first to minimize on-disk metadata inconsistencies.
657 *
658 * NOTE: We always perform synchronous i/o and ignore the @sync parameter.
659 * However, if the mft record has a counterpart in the mft mirror and @sync is
660 * true, we write the mft record, wait for i/o completion, and only then write
661 * the mft mirror copy. This ensures that if the system crashes either the mft
662 * or the mft mirror will contain a self-consistent mft record @m. If @sync is
663 * false on the other hand, we start i/o on both and then wait for completion
664 * on them. This provides a speedup but no longer guarantees that you will end
665 * up with a self-consistent mft record in the case of a crash but if you asked
666 * for asynchronous writing you probably do not care about that anyway.
667 *
668 * TODO: If @sync is false, want to do truly asynchronous i/o, i.e. just
669 * schedule i/o via ->writepage or do it via kntfsd or whatever.
670 */
671int write_mft_record_nolock(ntfs_inode *ni, MFT_RECORD *m, int sync)
672{
673 ntfs_volume *vol = ni->vol;
674 struct page *page = ni->page;
Anton Altaparmakov78af34f2006-02-24 10:32:33 +0000675 unsigned int blocksize = vol->sb->s_blocksize;
676 unsigned char blocksize_bits = vol->sb->s_blocksize_bits;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677 int max_bhs = vol->mft_record_size / blocksize;
678 struct buffer_head *bhs[max_bhs];
679 struct buffer_head *bh, *head;
680 runlist_element *rl;
681 unsigned int block_start, block_end, m_start, m_end;
682 int i_bhs, nr_bhs, err = 0;
683
684 ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
685 BUG_ON(NInoAttr(ni));
686 BUG_ON(!max_bhs);
687 BUG_ON(!PageLocked(page));
688 /*
689 * If the ntfs_inode is clean no need to do anything. If it is dirty,
690 * mark it as clean now so that it can be redirtied later on if needed.
691 * There is no danger of races since the caller is holding the locks
692 * for the mft record @m and the page it is in.
693 */
694 if (!NInoTestClearDirty(ni))
695 goto done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696 bh = head = page_buffers(page);
697 BUG_ON(!bh);
698 rl = NULL;
699 nr_bhs = 0;
700 block_start = 0;
701 m_start = ni->page_ofs;
702 m_end = m_start + vol->mft_record_size;
703 do {
704 block_end = block_start + blocksize;
705 /* If the buffer is outside the mft record, skip it. */
706 if (block_end <= m_start)
707 continue;
708 if (unlikely(block_start >= m_end))
709 break;
710 /*
711 * If this block is not the first one in the record, we ignore
712 * the buffer's dirty state because we could have raced with a
713 * parallel mark_ntfs_record_dirty().
714 */
715 if (block_start == m_start) {
716 /* This block is the first one in the record. */
717 if (!buffer_dirty(bh)) {
718 BUG_ON(nr_bhs);
719 /* Clean records are not written out. */
720 break;
721 }
722 }
723 /* Need to map the buffer if it is not mapped already. */
724 if (unlikely(!buffer_mapped(bh))) {
725 VCN vcn;
726 LCN lcn;
727 unsigned int vcn_ofs;
728
Anton Altaparmakove74589a2005-08-16 16:38:28 +0100729 bh->b_bdev = vol->sb->s_bdev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 /* Obtain the vcn and offset of the current block. */
731 vcn = ((VCN)ni->mft_no << vol->mft_record_size_bits) +
732 (block_start - m_start);
733 vcn_ofs = vcn & vol->cluster_size_mask;
734 vcn >>= vol->cluster_size_bits;
735 if (!rl) {
736 down_read(&NTFS_I(vol->mft_ino)->runlist.lock);
737 rl = NTFS_I(vol->mft_ino)->runlist.rl;
738 BUG_ON(!rl);
739 }
740 /* Seek to element containing target vcn. */
741 while (rl->length && rl[1].vcn <= vcn)
742 rl++;
743 lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
744 /* For $MFT, only lcn >= 0 is a successful remap. */
745 if (likely(lcn >= 0)) {
746 /* Setup buffer head to correct block. */
747 bh->b_blocknr = ((lcn <<
748 vol->cluster_size_bits) +
749 vcn_ofs) >> blocksize_bits;
750 set_buffer_mapped(bh);
751 } else {
752 bh->b_blocknr = -1;
753 ntfs_error(vol->sb, "Cannot write mft record "
754 "0x%lx because its location "
755 "on disk could not be "
756 "determined (error code %lli).",
757 ni->mft_no, (long long)lcn);
758 err = -EIO;
759 }
760 }
761 BUG_ON(!buffer_uptodate(bh));
762 BUG_ON(!nr_bhs && (m_start != block_start));
763 BUG_ON(nr_bhs >= max_bhs);
764 bhs[nr_bhs++] = bh;
765 BUG_ON((nr_bhs >= max_bhs) && (m_end != block_end));
766 } while (block_start = block_end, (bh = bh->b_this_page) != head);
767 if (unlikely(rl))
768 up_read(&NTFS_I(vol->mft_ino)->runlist.lock);
769 if (!nr_bhs)
770 goto done;
771 if (unlikely(err))
772 goto cleanup_out;
773 /* Apply the mst protection fixups. */
774 err = pre_write_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size);
775 if (err) {
776 ntfs_error(vol->sb, "Failed to apply mst fixups!");
777 goto cleanup_out;
778 }
779 flush_dcache_mft_record_page(ni);
780 /* Lock buffers and start synchronous write i/o on them. */
781 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
782 struct buffer_head *tbh = bhs[i_bhs];
783
784 if (unlikely(test_set_buffer_locked(tbh)))
785 BUG();
786 BUG_ON(!buffer_uptodate(tbh));
787 clear_buffer_dirty(tbh);
788 get_bh(tbh);
789 tbh->b_end_io = end_buffer_write_sync;
790 submit_bh(WRITE, tbh);
791 }
792 /* Synchronize the mft mirror now if not @sync. */
793 if (!sync && ni->mft_no < vol->mftmirr_size)
794 ntfs_sync_mft_mirror(vol, ni->mft_no, m, sync);
795 /* Wait on i/o completion of buffers. */
796 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
797 struct buffer_head *tbh = bhs[i_bhs];
798
799 wait_on_buffer(tbh);
800 if (unlikely(!buffer_uptodate(tbh))) {
801 err = -EIO;
802 /*
803 * Set the buffer uptodate so the page and buffer
804 * states do not become out of sync.
805 */
806 if (PageUptodate(page))
807 set_buffer_uptodate(tbh);
808 }
809 }
810 /* If @sync, now synchronize the mft mirror. */
811 if (sync && ni->mft_no < vol->mftmirr_size)
812 ntfs_sync_mft_mirror(vol, ni->mft_no, m, sync);
813 /* Remove the mst protection fixups again. */
814 post_write_mst_fixup((NTFS_RECORD*)m);
815 flush_dcache_mft_record_page(ni);
816 if (unlikely(err)) {
817 /* I/O error during writing. This is really bad! */
818 ntfs_error(vol->sb, "I/O error while writing mft record "
819 "0x%lx! Marking base inode as bad. You "
820 "should unmount the volume and run chkdsk.",
821 ni->mft_no);
822 goto err_out;
823 }
824done:
825 ntfs_debug("Done.");
826 return 0;
827cleanup_out:
828 /* Clean the buffers. */
829 for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++)
830 clear_buffer_dirty(bhs[i_bhs]);
831err_out:
832 /*
833 * Current state: all buffers are clean, unlocked, and uptodate.
834 * The caller should mark the base inode as bad so that no more i/o
835 * happens. ->clear_inode() will still be invoked so all extent inodes
836 * and other allocated memory will be freed.
837 */
838 if (err == -ENOMEM) {
839 ntfs_error(vol->sb, "Not enough memory to write mft record. "
840 "Redirtying so the write is retried later.");
841 mark_mft_record_dirty(ni);
842 err = 0;
843 } else
844 NVolSetErrors(vol);
845 return err;
846}
847
848/**
849 * ntfs_may_write_mft_record - check if an mft record may be written out
850 * @vol: [IN] ntfs volume on which the mft record to check resides
851 * @mft_no: [IN] mft record number of the mft record to check
852 * @m: [IN] mapped mft record to check
853 * @locked_ni: [OUT] caller has to unlock this ntfs inode if one is returned
854 *
855 * Check if the mapped (base or extent) mft record @m with mft record number
856 * @mft_no belonging to the ntfs volume @vol may be written out. If necessary
857 * and possible the ntfs inode of the mft record is locked and the base vfs
858 * inode is pinned. The locked ntfs inode is then returned in @locked_ni. The
859 * caller is responsible for unlocking the ntfs inode and unpinning the base
860 * vfs inode.
861 *
862 * Return TRUE if the mft record may be written out and FALSE if not.
863 *
864 * The caller has locked the page and cleared the uptodate flag on it which
865 * means that we can safely write out any dirty mft records that do not have
866 * their inodes in icache as determined by ilookup5() as anyone
867 * opening/creating such an inode would block when attempting to map the mft
868 * record in read_cache_page() until we are finished with the write out.
869 *
870 * Here is a description of the tests we perform:
871 *
872 * If the inode is found in icache we know the mft record must be a base mft
873 * record. If it is dirty, we do not write it and return FALSE as the vfs
874 * inode write paths will result in the access times being updated which would
875 * cause the base mft record to be redirtied and written out again. (We know
876 * the access time update will modify the base mft record because Windows
877 * chkdsk complains if the standard information attribute is not in the base
878 * mft record.)
879 *
880 * If the inode is in icache and not dirty, we attempt to lock the mft record
881 * and if we find the lock was already taken, it is not safe to write the mft
882 * record and we return FALSE.
883 *
884 * If we manage to obtain the lock we have exclusive access to the mft record,
885 * which also allows us safe writeout of the mft record. We then set
886 * @locked_ni to the locked ntfs inode and return TRUE.
887 *
888 * Note we cannot just lock the mft record and sleep while waiting for the lock
889 * because this would deadlock due to lock reversal (normally the mft record is
890 * locked before the page is locked but we already have the page locked here
891 * when we try to lock the mft record).
892 *
893 * If the inode is not in icache we need to perform further checks.
894 *
895 * If the mft record is not a FILE record or it is a base mft record, we can
896 * safely write it and return TRUE.
897 *
898 * We now know the mft record is an extent mft record. We check if the inode
899 * corresponding to its base mft record is in icache and obtain a reference to
900 * it if it is. If it is not, we can safely write it and return TRUE.
901 *
902 * We now have the base inode for the extent mft record. We check if it has an
903 * ntfs inode for the extent mft record attached and if not it is safe to write
904 * the extent mft record and we return TRUE.
905 *
906 * The ntfs inode for the extent mft record is attached to the base inode so we
907 * attempt to lock the extent mft record and if we find the lock was already
908 * taken, it is not safe to write the extent mft record and we return FALSE.
909 *
910 * If we manage to obtain the lock we have exclusive access to the extent mft
911 * record, which also allows us safe writeout of the extent mft record. We
912 * set the ntfs inode of the extent mft record clean and then set @locked_ni to
913 * the now locked ntfs inode and return TRUE.
914 *
915 * Note, the reason for actually writing dirty mft records here and not just
916 * relying on the vfs inode dirty code paths is that we can have mft records
917 * modified without them ever having actual inodes in memory. Also we can have
918 * dirty mft records with clean ntfs inodes in memory. None of the described
919 * cases would result in the dirty mft records being written out if we only
920 * relied on the vfs inode dirty code paths. And these cases can really occur
921 * during allocation of new mft records and in particular when the
922 * initialized_size of the $MFT/$DATA attribute is extended and the new space
923 * is initialized using ntfs_mft_record_format(). The clean inode can then
924 * appear if the mft record is reused for a new inode before it got written
925 * out.
926 */
927BOOL ntfs_may_write_mft_record(ntfs_volume *vol, const unsigned long mft_no,
928 const MFT_RECORD *m, ntfs_inode **locked_ni)
929{
930 struct super_block *sb = vol->sb;
931 struct inode *mft_vi = vol->mft_ino;
932 struct inode *vi;
933 ntfs_inode *ni, *eni, **extent_nis;
934 int i;
935 ntfs_attr na;
936
937 ntfs_debug("Entering for inode 0x%lx.", mft_no);
938 /*
939 * Normally we do not return a locked inode so set @locked_ni to NULL.
940 */
941 BUG_ON(!locked_ni);
942 *locked_ni = NULL;
943 /*
944 * Check if the inode corresponding to this mft record is in the VFS
945 * inode cache and obtain a reference to it if it is.
946 */
947 ntfs_debug("Looking for inode 0x%lx in icache.", mft_no);
948 na.mft_no = mft_no;
949 na.name = NULL;
950 na.name_len = 0;
951 na.type = AT_UNUSED;
952 /*
Anton Altaparmakovba6d2372005-06-26 22:12:02 +0100953 * Optimize inode 0, i.e. $MFT itself, since we have it in memory and
954 * we get here for it rather often.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955 */
956 if (!mft_no) {
957 /* Balance the below iput(). */
958 vi = igrab(mft_vi);
959 BUG_ON(vi != mft_vi);
Anton Altaparmakovba6d2372005-06-26 22:12:02 +0100960 } else {
961 /*
962 * Have to use ilookup5_nowait() since ilookup5() waits for the
963 * inode lock which causes ntfs to deadlock when a concurrent
964 * inode write via the inode dirty code paths and the page
965 * dirty code path of the inode dirty code path when writing
966 * $MFT occurs.
967 */
968 vi = ilookup5_nowait(sb, mft_no, (test_t)ntfs_test_inode, &na);
969 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 if (vi) {
971 ntfs_debug("Base inode 0x%lx is in icache.", mft_no);
972 /* The inode is in icache. */
973 ni = NTFS_I(vi);
974 /* Take a reference to the ntfs inode. */
975 atomic_inc(&ni->count);
976 /* If the inode is dirty, do not write this record. */
977 if (NInoDirty(ni)) {
978 ntfs_debug("Inode 0x%lx is dirty, do not write it.",
979 mft_no);
980 atomic_dec(&ni->count);
981 iput(vi);
982 return FALSE;
983 }
984 ntfs_debug("Inode 0x%lx is not dirty.", mft_no);
985 /* The inode is not dirty, try to take the mft record lock. */
986 if (unlikely(down_trylock(&ni->mrec_lock))) {
987 ntfs_debug("Mft record 0x%lx is already locked, do "
988 "not write it.", mft_no);
989 atomic_dec(&ni->count);
990 iput(vi);
991 return FALSE;
992 }
993 ntfs_debug("Managed to lock mft record 0x%lx, write it.",
994 mft_no);
995 /*
996 * The write has to occur while we hold the mft record lock so
997 * return the locked ntfs inode.
998 */
999 *locked_ni = ni;
1000 return TRUE;
1001 }
1002 ntfs_debug("Inode 0x%lx is not in icache.", mft_no);
1003 /* The inode is not in icache. */
1004 /* Write the record if it is not a mft record (type "FILE"). */
1005 if (!ntfs_is_mft_record(m->magic)) {
1006 ntfs_debug("Mft record 0x%lx is not a FILE record, write it.",
1007 mft_no);
1008 return TRUE;
1009 }
1010 /* Write the mft record if it is a base inode. */
1011 if (!m->base_mft_record) {
1012 ntfs_debug("Mft record 0x%lx is a base record, write it.",
1013 mft_no);
1014 return TRUE;
1015 }
1016 /*
1017 * This is an extent mft record. Check if the inode corresponding to
1018 * its base mft record is in icache and obtain a reference to it if it
1019 * is.
1020 */
1021 na.mft_no = MREF_LE(m->base_mft_record);
1022 ntfs_debug("Mft record 0x%lx is an extent record. Looking for base "
1023 "inode 0x%lx in icache.", mft_no, na.mft_no);
Anton Altaparmakovba6d2372005-06-26 22:12:02 +01001024 if (!na.mft_no) {
1025 /* Balance the below iput(). */
1026 vi = igrab(mft_vi);
1027 BUG_ON(vi != mft_vi);
1028 } else
1029 vi = ilookup5_nowait(sb, na.mft_no, (test_t)ntfs_test_inode,
1030 &na);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001031 if (!vi) {
1032 /*
1033 * The base inode is not in icache, write this extent mft
1034 * record.
1035 */
1036 ntfs_debug("Base inode 0x%lx is not in icache, write the "
1037 "extent record.", na.mft_no);
1038 return TRUE;
1039 }
1040 ntfs_debug("Base inode 0x%lx is in icache.", na.mft_no);
1041 /*
1042 * The base inode is in icache. Check if it has the extent inode
1043 * corresponding to this extent mft record attached.
1044 */
1045 ni = NTFS_I(vi);
1046 down(&ni->extent_lock);
1047 if (ni->nr_extents <= 0) {
1048 /*
1049 * The base inode has no attached extent inodes, write this
1050 * extent mft record.
1051 */
1052 up(&ni->extent_lock);
1053 iput(vi);
1054 ntfs_debug("Base inode 0x%lx has no attached extent inodes, "
1055 "write the extent record.", na.mft_no);
1056 return TRUE;
1057 }
1058 /* Iterate over the attached extent inodes. */
1059 extent_nis = ni->ext.extent_ntfs_inos;
1060 for (eni = NULL, i = 0; i < ni->nr_extents; ++i) {
1061 if (mft_no == extent_nis[i]->mft_no) {
1062 /*
1063 * Found the extent inode corresponding to this extent
1064 * mft record.
1065 */
1066 eni = extent_nis[i];
1067 break;
1068 }
1069 }
1070 /*
1071 * If the extent inode was not attached to the base inode, write this
1072 * extent mft record.
1073 */
1074 if (!eni) {
1075 up(&ni->extent_lock);
1076 iput(vi);
1077 ntfs_debug("Extent inode 0x%lx is not attached to its base "
1078 "inode 0x%lx, write the extent record.",
1079 mft_no, na.mft_no);
1080 return TRUE;
1081 }
1082 ntfs_debug("Extent inode 0x%lx is attached to its base inode 0x%lx.",
1083 mft_no, na.mft_no);
1084 /* Take a reference to the extent ntfs inode. */
1085 atomic_inc(&eni->count);
1086 up(&ni->extent_lock);
1087 /*
1088 * Found the extent inode coresponding to this extent mft record.
1089 * Try to take the mft record lock.
1090 */
1091 if (unlikely(down_trylock(&eni->mrec_lock))) {
1092 atomic_dec(&eni->count);
1093 iput(vi);
1094 ntfs_debug("Extent mft record 0x%lx is already locked, do "
1095 "not write it.", mft_no);
1096 return FALSE;
1097 }
1098 ntfs_debug("Managed to lock extent mft record 0x%lx, write it.",
1099 mft_no);
1100 if (NInoTestClearDirty(eni))
1101 ntfs_debug("Extent inode 0x%lx is dirty, marking it clean.",
1102 mft_no);
1103 /*
1104 * The write has to occur while we hold the mft record lock so return
1105 * the locked extent ntfs inode.
1106 */
1107 *locked_ni = eni;
1108 return TRUE;
1109}
1110
1111static const char *es = " Leaving inconsistent metadata. Unmount and run "
1112 "chkdsk.";
1113
1114/**
1115 * ntfs_mft_bitmap_find_and_alloc_free_rec_nolock - see name
1116 * @vol: volume on which to search for a free mft record
1117 * @base_ni: open base inode if allocating an extent mft record or NULL
1118 *
1119 * Search for a free mft record in the mft bitmap attribute on the ntfs volume
1120 * @vol.
1121 *
1122 * If @base_ni is NULL start the search at the default allocator position.
1123 *
1124 * If @base_ni is not NULL start the search at the mft record after the base
1125 * mft record @base_ni.
1126 *
1127 * Return the free mft record on success and -errno on error. An error code of
1128 * -ENOSPC means that there are no free mft records in the currently
1129 * initialized mft bitmap.
1130 *
1131 * Locking: Caller must hold vol->mftbmp_lock for writing.
1132 */
1133static int ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(ntfs_volume *vol,
1134 ntfs_inode *base_ni)
1135{
1136 s64 pass_end, ll, data_pos, pass_start, ofs, bit;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001137 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138 struct address_space *mftbmp_mapping;
1139 u8 *buf, *byte;
1140 struct page *page;
1141 unsigned int page_ofs, size;
1142 u8 pass, b;
1143
1144 ntfs_debug("Searching for free mft record in the currently "
1145 "initialized mft bitmap.");
1146 mftbmp_mapping = vol->mftbmp_ino->i_mapping;
1147 /*
1148 * Set the end of the pass making sure we do not overflow the mft
1149 * bitmap.
1150 */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001151 read_lock_irqsave(&NTFS_I(vol->mft_ino)->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 pass_end = NTFS_I(vol->mft_ino)->allocated_size >>
1153 vol->mft_record_size_bits;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001154 read_unlock_irqrestore(&NTFS_I(vol->mft_ino)->size_lock, flags);
1155 read_lock_irqsave(&NTFS_I(vol->mftbmp_ino)->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156 ll = NTFS_I(vol->mftbmp_ino)->initialized_size << 3;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001157 read_unlock_irqrestore(&NTFS_I(vol->mftbmp_ino)->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001158 if (pass_end > ll)
1159 pass_end = ll;
1160 pass = 1;
1161 if (!base_ni)
1162 data_pos = vol->mft_data_pos;
1163 else
1164 data_pos = base_ni->mft_no + 1;
1165 if (data_pos < 24)
1166 data_pos = 24;
1167 if (data_pos >= pass_end) {
1168 data_pos = 24;
1169 pass = 2;
1170 /* This happens on a freshly formatted volume. */
1171 if (data_pos >= pass_end)
1172 return -ENOSPC;
1173 }
1174 pass_start = data_pos;
1175 ntfs_debug("Starting bitmap search: pass %u, pass_start 0x%llx, "
1176 "pass_end 0x%llx, data_pos 0x%llx.", pass,
1177 (long long)pass_start, (long long)pass_end,
1178 (long long)data_pos);
1179 /* Loop until a free mft record is found. */
1180 for (; pass <= 2;) {
1181 /* Cap size to pass_end. */
1182 ofs = data_pos >> 3;
1183 page_ofs = ofs & ~PAGE_CACHE_MASK;
1184 size = PAGE_CACHE_SIZE - page_ofs;
1185 ll = ((pass_end + 7) >> 3) - ofs;
1186 if (size > ll)
1187 size = ll;
1188 size <<= 3;
1189 /*
1190 * If we are still within the active pass, search the next page
1191 * for a zero bit.
1192 */
1193 if (size) {
1194 page = ntfs_map_page(mftbmp_mapping,
1195 ofs >> PAGE_CACHE_SHIFT);
1196 if (unlikely(IS_ERR(page))) {
1197 ntfs_error(vol->sb, "Failed to read mft "
1198 "bitmap, aborting.");
1199 return PTR_ERR(page);
1200 }
1201 buf = (u8*)page_address(page) + page_ofs;
1202 bit = data_pos & 7;
1203 data_pos &= ~7ull;
1204 ntfs_debug("Before inner for loop: size 0x%x, "
1205 "data_pos 0x%llx, bit 0x%llx", size,
1206 (long long)data_pos, (long long)bit);
1207 for (; bit < size && data_pos + bit < pass_end;
1208 bit &= ~7ull, bit += 8) {
1209 byte = buf + (bit >> 3);
1210 if (*byte == 0xff)
1211 continue;
1212 b = ffz((unsigned long)*byte);
1213 if (b < 8 && b >= (bit & 7)) {
1214 ll = data_pos + (bit & ~7ull) + b;
1215 if (unlikely(ll > (1ll << 32))) {
1216 ntfs_unmap_page(page);
1217 return -ENOSPC;
1218 }
1219 *byte |= 1 << b;
1220 flush_dcache_page(page);
1221 set_page_dirty(page);
1222 ntfs_unmap_page(page);
1223 ntfs_debug("Done. (Found and "
1224 "allocated mft record "
1225 "0x%llx.)",
1226 (long long)ll);
1227 return ll;
1228 }
1229 }
1230 ntfs_debug("After inner for loop: size 0x%x, "
1231 "data_pos 0x%llx, bit 0x%llx", size,
1232 (long long)data_pos, (long long)bit);
1233 data_pos += size;
1234 ntfs_unmap_page(page);
1235 /*
1236 * If the end of the pass has not been reached yet,
1237 * continue searching the mft bitmap for a zero bit.
1238 */
1239 if (data_pos < pass_end)
1240 continue;
1241 }
1242 /* Do the next pass. */
1243 if (++pass == 2) {
1244 /*
1245 * Starting the second pass, in which we scan the first
1246 * part of the zone which we omitted earlier.
1247 */
1248 pass_end = pass_start;
1249 data_pos = pass_start = 24;
1250 ntfs_debug("pass %i, pass_start 0x%llx, pass_end "
1251 "0x%llx.", pass, (long long)pass_start,
1252 (long long)pass_end);
1253 if (data_pos >= pass_end)
1254 break;
1255 }
1256 }
1257 /* No free mft records in currently initialized mft bitmap. */
1258 ntfs_debug("Done. (No free mft records left in currently initialized "
1259 "mft bitmap.)");
1260 return -ENOSPC;
1261}
1262
1263/**
1264 * ntfs_mft_bitmap_extend_allocation_nolock - extend mft bitmap by a cluster
1265 * @vol: volume on which to extend the mft bitmap attribute
1266 *
1267 * Extend the mft bitmap attribute on the ntfs volume @vol by one cluster.
1268 *
1269 * Note: Only changes allocated_size, i.e. does not touch initialized_size or
1270 * data_size.
1271 *
1272 * Return 0 on success and -errno on error.
1273 *
1274 * Locking: - Caller must hold vol->mftbmp_lock for writing.
1275 * - This function takes NTFS_I(vol->mftbmp_ino)->runlist.lock for
1276 * writing and releases it before returning.
1277 * - This function takes vol->lcnbmp_lock for writing and releases it
1278 * before returning.
1279 */
1280static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
1281{
1282 LCN lcn;
1283 s64 ll;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001284 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001285 struct page *page;
1286 ntfs_inode *mft_ni, *mftbmp_ni;
1287 runlist_element *rl, *rl2 = NULL;
1288 ntfs_attr_search_ctx *ctx = NULL;
1289 MFT_RECORD *mrec;
1290 ATTR_RECORD *a = NULL;
1291 int ret, mp_size;
1292 u32 old_alen = 0;
1293 u8 *b, tb;
1294 struct {
1295 u8 added_cluster:1;
1296 u8 added_run:1;
1297 u8 mp_rebuilt:1;
1298 } status = { 0, 0, 0 };
1299
1300 ntfs_debug("Extending mft bitmap allocation.");
1301 mft_ni = NTFS_I(vol->mft_ino);
1302 mftbmp_ni = NTFS_I(vol->mftbmp_ino);
1303 /*
1304 * Determine the last lcn of the mft bitmap. The allocated size of the
1305 * mft bitmap cannot be zero so we are ok to do this.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001306 */
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001307 down_write(&mftbmp_ni->runlist.lock);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001308 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
1309 ll = mftbmp_ni->allocated_size;
1310 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
Anton Altaparmakovc0c1cc02005-03-07 21:43:38 +00001311 rl = ntfs_attr_find_vcn_nolock(mftbmp_ni,
Anton Altaparmakov69b41e32005-10-04 14:01:14 +01001312 (ll - 1) >> vol->cluster_size_bits, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001313 if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001314 up_write(&mftbmp_ni->runlist.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001315 ntfs_error(vol->sb, "Failed to determine last allocated "
1316 "cluster of mft bitmap attribute.");
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001317 if (!IS_ERR(rl))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318 ret = -EIO;
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001319 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320 ret = PTR_ERR(rl);
1321 return ret;
1322 }
1323 lcn = rl->lcn + rl->length;
1324 ntfs_debug("Last lcn of mft bitmap attribute is 0x%llx.",
1325 (long long)lcn);
1326 /*
1327 * Attempt to get the cluster following the last allocated cluster by
1328 * hand as it may be in the MFT zone so the allocator would not give it
1329 * to us.
1330 */
1331 ll = lcn >> 3;
1332 page = ntfs_map_page(vol->lcnbmp_ino->i_mapping,
1333 ll >> PAGE_CACHE_SHIFT);
1334 if (IS_ERR(page)) {
1335 up_write(&mftbmp_ni->runlist.lock);
1336 ntfs_error(vol->sb, "Failed to read from lcn bitmap.");
1337 return PTR_ERR(page);
1338 }
1339 b = (u8*)page_address(page) + (ll & ~PAGE_CACHE_MASK);
1340 tb = 1 << (lcn & 7ull);
1341 down_write(&vol->lcnbmp_lock);
1342 if (*b != 0xff && !(*b & tb)) {
1343 /* Next cluster is free, allocate it. */
1344 *b |= tb;
1345 flush_dcache_page(page);
1346 set_page_dirty(page);
1347 up_write(&vol->lcnbmp_lock);
1348 ntfs_unmap_page(page);
1349 /* Update the mft bitmap runlist. */
1350 rl->length++;
1351 rl[1].vcn++;
1352 status.added_cluster = 1;
1353 ntfs_debug("Appending one cluster to mft bitmap.");
1354 } else {
1355 up_write(&vol->lcnbmp_lock);
1356 ntfs_unmap_page(page);
1357 /* Allocate a cluster from the DATA_ZONE. */
Anton Altaparmakovfc0fa7d2005-10-04 14:36:56 +01001358 rl2 = ntfs_cluster_alloc(vol, rl[1].vcn, 1, lcn, DATA_ZONE,
1359 TRUE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 if (IS_ERR(rl2)) {
1361 up_write(&mftbmp_ni->runlist.lock);
1362 ntfs_error(vol->sb, "Failed to allocate a cluster for "
1363 "the mft bitmap.");
1364 return PTR_ERR(rl2);
1365 }
1366 rl = ntfs_runlists_merge(mftbmp_ni->runlist.rl, rl2);
1367 if (IS_ERR(rl)) {
1368 up_write(&mftbmp_ni->runlist.lock);
1369 ntfs_error(vol->sb, "Failed to merge runlists for mft "
1370 "bitmap.");
1371 if (ntfs_cluster_free_from_rl(vol, rl2)) {
1372 ntfs_error(vol->sb, "Failed to dealocate "
1373 "allocated cluster.%s", es);
1374 NVolSetErrors(vol);
1375 }
1376 ntfs_free(rl2);
1377 return PTR_ERR(rl);
1378 }
1379 mftbmp_ni->runlist.rl = rl;
1380 status.added_run = 1;
1381 ntfs_debug("Adding one run to mft bitmap.");
1382 /* Find the last run in the new runlist. */
1383 for (; rl[1].length; rl++)
1384 ;
1385 }
1386 /*
1387 * Update the attribute record as well. Note: @rl is the last
1388 * (non-terminator) runlist element of mft bitmap.
1389 */
1390 mrec = map_mft_record(mft_ni);
1391 if (IS_ERR(mrec)) {
1392 ntfs_error(vol->sb, "Failed to map mft record.");
1393 ret = PTR_ERR(mrec);
1394 goto undo_alloc;
1395 }
1396 ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
1397 if (unlikely(!ctx)) {
1398 ntfs_error(vol->sb, "Failed to get search context.");
1399 ret = -ENOMEM;
1400 goto undo_alloc;
1401 }
1402 ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
1403 mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
1404 0, ctx);
1405 if (unlikely(ret)) {
1406 ntfs_error(vol->sb, "Failed to find last attribute extent of "
1407 "mft bitmap attribute.");
1408 if (ret == -ENOENT)
1409 ret = -EIO;
1410 goto undo_alloc;
1411 }
1412 a = ctx->attr;
1413 ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
1414 /* Search back for the previous last allocated cluster of mft bitmap. */
1415 for (rl2 = rl; rl2 > mftbmp_ni->runlist.rl; rl2--) {
1416 if (ll >= rl2->vcn)
1417 break;
1418 }
1419 BUG_ON(ll < rl2->vcn);
1420 BUG_ON(ll >= rl2->vcn + rl2->length);
1421 /* Get the size for the new mapping pairs array for this extent. */
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001422 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001423 if (unlikely(mp_size <= 0)) {
1424 ntfs_error(vol->sb, "Get size for mapping pairs failed for "
1425 "mft bitmap attribute extent.");
1426 ret = mp_size;
1427 if (!ret)
1428 ret = -EIO;
1429 goto undo_alloc;
1430 }
1431 /* Expand the attribute record if necessary. */
1432 old_alen = le32_to_cpu(a->length);
1433 ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
1434 le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
1435 if (unlikely(ret)) {
1436 if (ret != -ENOSPC) {
1437 ntfs_error(vol->sb, "Failed to resize attribute "
1438 "record for mft bitmap attribute.");
1439 goto undo_alloc;
1440 }
1441 // TODO: Deal with this by moving this extent to a new mft
1442 // record or by starting a new extent in a new mft record or by
1443 // moving other attributes out of this mft record.
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001444 // Note: It will need to be a special mft record and if none of
1445 // those are available it gets rather complicated...
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 ntfs_error(vol->sb, "Not enough space in this mft record to "
1447 "accomodate extended mft bitmap attribute "
1448 "extent. Cannot handle this yet.");
1449 ret = -EOPNOTSUPP;
1450 goto undo_alloc;
1451 }
1452 status.mp_rebuilt = 1;
1453 /* Generate the mapping pairs array directly into the attr record. */
1454 ret = ntfs_mapping_pairs_build(vol, (u8*)a +
1455 le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001456 mp_size, rl2, ll, -1, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457 if (unlikely(ret)) {
1458 ntfs_error(vol->sb, "Failed to build mapping pairs array for "
1459 "mft bitmap attribute.");
1460 goto undo_alloc;
1461 }
1462 /* Update the highest_vcn. */
1463 a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
1464 /*
1465 * We now have extended the mft bitmap allocated_size by one cluster.
1466 * Reflect this in the ntfs_inode structure and the attribute record.
1467 */
1468 if (a->data.non_resident.lowest_vcn) {
1469 /*
1470 * We are not in the first attribute extent, switch to it, but
1471 * first ensure the changes will make it to disk later.
1472 */
1473 flush_dcache_mft_record_page(ctx->ntfs_ino);
1474 mark_mft_record_dirty(ctx->ntfs_ino);
1475 ntfs_attr_reinit_search_ctx(ctx);
1476 ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
1477 mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL,
1478 0, ctx);
1479 if (unlikely(ret)) {
1480 ntfs_error(vol->sb, "Failed to find first attribute "
1481 "extent of mft bitmap attribute.");
1482 goto restore_undo_alloc;
1483 }
1484 a = ctx->attr;
1485 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001486 write_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487 mftbmp_ni->allocated_size += vol->cluster_size;
1488 a->data.non_resident.allocated_size =
1489 cpu_to_sle64(mftbmp_ni->allocated_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001490 write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001491 /* Ensure the changes make it to disk. */
1492 flush_dcache_mft_record_page(ctx->ntfs_ino);
1493 mark_mft_record_dirty(ctx->ntfs_ino);
1494 ntfs_attr_put_search_ctx(ctx);
1495 unmap_mft_record(mft_ni);
1496 up_write(&mftbmp_ni->runlist.lock);
1497 ntfs_debug("Done.");
1498 return 0;
1499restore_undo_alloc:
1500 ntfs_attr_reinit_search_ctx(ctx);
1501 if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
1502 mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
1503 0, ctx)) {
1504 ntfs_error(vol->sb, "Failed to find last attribute extent of "
1505 "mft bitmap attribute.%s", es);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001506 write_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507 mftbmp_ni->allocated_size += vol->cluster_size;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001508 write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509 ntfs_attr_put_search_ctx(ctx);
1510 unmap_mft_record(mft_ni);
1511 up_write(&mftbmp_ni->runlist.lock);
1512 /*
1513 * The only thing that is now wrong is ->allocated_size of the
1514 * base attribute extent which chkdsk should be able to fix.
1515 */
1516 NVolSetErrors(vol);
1517 return ret;
1518 }
1519 a = ctx->attr;
1520 a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 2);
1521undo_alloc:
1522 if (status.added_cluster) {
1523 /* Truncate the last run in the runlist by one cluster. */
1524 rl->length--;
1525 rl[1].vcn--;
1526 } else if (status.added_run) {
1527 lcn = rl->lcn;
1528 /* Remove the last run from the runlist. */
1529 rl->lcn = rl[1].lcn;
1530 rl->length = 0;
1531 }
1532 /* Deallocate the cluster. */
1533 down_write(&vol->lcnbmp_lock);
1534 if (ntfs_bitmap_clear_bit(vol->lcnbmp_ino, lcn)) {
1535 ntfs_error(vol->sb, "Failed to free allocated cluster.%s", es);
1536 NVolSetErrors(vol);
1537 }
1538 up_write(&vol->lcnbmp_lock);
1539 if (status.mp_rebuilt) {
1540 if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
1541 a->data.non_resident.mapping_pairs_offset),
1542 old_alen - le16_to_cpu(
1543 a->data.non_resident.mapping_pairs_offset),
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001544 rl2, ll, -1, NULL)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545 ntfs_error(vol->sb, "Failed to restore mapping pairs "
1546 "array.%s", es);
1547 NVolSetErrors(vol);
1548 }
1549 if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
1550 ntfs_error(vol->sb, "Failed to restore attribute "
1551 "record.%s", es);
1552 NVolSetErrors(vol);
1553 }
1554 flush_dcache_mft_record_page(ctx->ntfs_ino);
1555 mark_mft_record_dirty(ctx->ntfs_ino);
1556 }
1557 if (ctx)
1558 ntfs_attr_put_search_ctx(ctx);
1559 if (!IS_ERR(mrec))
1560 unmap_mft_record(mft_ni);
1561 up_write(&mftbmp_ni->runlist.lock);
1562 return ret;
1563}
1564
1565/**
1566 * ntfs_mft_bitmap_extend_initialized_nolock - extend mftbmp initialized data
1567 * @vol: volume on which to extend the mft bitmap attribute
1568 *
1569 * Extend the initialized portion of the mft bitmap attribute on the ntfs
1570 * volume @vol by 8 bytes.
1571 *
1572 * Note: Only changes initialized_size and data_size, i.e. requires that
1573 * allocated_size is big enough to fit the new initialized_size.
1574 *
1575 * Return 0 on success and -error on error.
1576 *
1577 * Locking: Caller must hold vol->mftbmp_lock for writing.
1578 */
1579static int ntfs_mft_bitmap_extend_initialized_nolock(ntfs_volume *vol)
1580{
1581 s64 old_data_size, old_initialized_size;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001582 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001583 struct inode *mftbmp_vi;
1584 ntfs_inode *mft_ni, *mftbmp_ni;
1585 ntfs_attr_search_ctx *ctx;
1586 MFT_RECORD *mrec;
1587 ATTR_RECORD *a;
1588 int ret;
1589
1590 ntfs_debug("Extending mft bitmap initiailized (and data) size.");
1591 mft_ni = NTFS_I(vol->mft_ino);
1592 mftbmp_vi = vol->mftbmp_ino;
1593 mftbmp_ni = NTFS_I(mftbmp_vi);
1594 /* Get the attribute record. */
1595 mrec = map_mft_record(mft_ni);
1596 if (IS_ERR(mrec)) {
1597 ntfs_error(vol->sb, "Failed to map mft record.");
1598 return PTR_ERR(mrec);
1599 }
1600 ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
1601 if (unlikely(!ctx)) {
1602 ntfs_error(vol->sb, "Failed to get search context.");
1603 ret = -ENOMEM;
1604 goto unm_err_out;
1605 }
1606 ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
1607 mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx);
1608 if (unlikely(ret)) {
1609 ntfs_error(vol->sb, "Failed to find first attribute extent of "
1610 "mft bitmap attribute.");
1611 if (ret == -ENOENT)
1612 ret = -EIO;
1613 goto put_err_out;
1614 }
1615 a = ctx->attr;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001616 write_lock_irqsave(&mftbmp_ni->size_lock, flags);
1617 old_data_size = i_size_read(mftbmp_vi);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001618 old_initialized_size = mftbmp_ni->initialized_size;
1619 /*
1620 * We can simply update the initialized_size before filling the space
1621 * with zeroes because the caller is holding the mft bitmap lock for
1622 * writing which ensures that no one else is trying to access the data.
1623 */
1624 mftbmp_ni->initialized_size += 8;
1625 a->data.non_resident.initialized_size =
1626 cpu_to_sle64(mftbmp_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001627 if (mftbmp_ni->initialized_size > old_data_size) {
1628 i_size_write(mftbmp_vi, mftbmp_ni->initialized_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001629 a->data.non_resident.data_size =
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001630 cpu_to_sle64(mftbmp_ni->initialized_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001632 write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633 /* Ensure the changes make it to disk. */
1634 flush_dcache_mft_record_page(ctx->ntfs_ino);
1635 mark_mft_record_dirty(ctx->ntfs_ino);
1636 ntfs_attr_put_search_ctx(ctx);
1637 unmap_mft_record(mft_ni);
1638 /* Initialize the mft bitmap attribute value with zeroes. */
1639 ret = ntfs_attr_set(mftbmp_ni, old_initialized_size, 8, 0);
1640 if (likely(!ret)) {
1641 ntfs_debug("Done. (Wrote eight initialized bytes to mft "
1642 "bitmap.");
1643 return 0;
1644 }
1645 ntfs_error(vol->sb, "Failed to write to mft bitmap.");
1646 /* Try to recover from the error. */
1647 mrec = map_mft_record(mft_ni);
1648 if (IS_ERR(mrec)) {
1649 ntfs_error(vol->sb, "Failed to map mft record.%s", es);
1650 NVolSetErrors(vol);
1651 return ret;
1652 }
1653 ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
1654 if (unlikely(!ctx)) {
1655 ntfs_error(vol->sb, "Failed to get search context.%s", es);
1656 NVolSetErrors(vol);
1657 goto unm_err_out;
1658 }
1659 if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
1660 mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) {
1661 ntfs_error(vol->sb, "Failed to find first attribute extent of "
1662 "mft bitmap attribute.%s", es);
1663 NVolSetErrors(vol);
1664put_err_out:
1665 ntfs_attr_put_search_ctx(ctx);
1666unm_err_out:
1667 unmap_mft_record(mft_ni);
1668 goto err_out;
1669 }
1670 a = ctx->attr;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001671 write_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672 mftbmp_ni->initialized_size = old_initialized_size;
1673 a->data.non_resident.initialized_size =
1674 cpu_to_sle64(old_initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001675 if (i_size_read(mftbmp_vi) != old_data_size) {
1676 i_size_write(mftbmp_vi, old_data_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001677 a->data.non_resident.data_size = cpu_to_sle64(old_data_size);
1678 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001679 write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001680 flush_dcache_mft_record_page(ctx->ntfs_ino);
1681 mark_mft_record_dirty(ctx->ntfs_ino);
1682 ntfs_attr_put_search_ctx(ctx);
1683 unmap_mft_record(mft_ni);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001684#ifdef DEBUG
1685 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001686 ntfs_debug("Restored status of mftbmp: allocated_size 0x%llx, "
1687 "data_size 0x%llx, initialized_size 0x%llx.",
1688 (long long)mftbmp_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001689 (long long)i_size_read(mftbmp_vi),
Linus Torvalds1da177e2005-04-16 15:20:36 -07001690 (long long)mftbmp_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001691 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
1692#endif /* DEBUG */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693err_out:
1694 return ret;
1695}
1696
1697/**
1698 * ntfs_mft_data_extend_allocation_nolock - extend mft data attribute
1699 * @vol: volume on which to extend the mft data attribute
1700 *
1701 * Extend the mft data attribute on the ntfs volume @vol by 16 mft records
1702 * worth of clusters or if not enough space for this by one mft record worth
1703 * of clusters.
1704 *
1705 * Note: Only changes allocated_size, i.e. does not touch initialized_size or
1706 * data_size.
1707 *
1708 * Return 0 on success and -errno on error.
1709 *
1710 * Locking: - Caller must hold vol->mftbmp_lock for writing.
1711 * - This function takes NTFS_I(vol->mft_ino)->runlist.lock for
1712 * writing and releases it before returning.
1713 * - This function calls functions which take vol->lcnbmp_lock for
1714 * writing and release it before returning.
1715 */
1716static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
1717{
1718 LCN lcn;
1719 VCN old_last_vcn;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001720 s64 min_nr, nr, ll;
1721 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001722 ntfs_inode *mft_ni;
1723 runlist_element *rl, *rl2;
1724 ntfs_attr_search_ctx *ctx = NULL;
1725 MFT_RECORD *mrec;
1726 ATTR_RECORD *a = NULL;
1727 int ret, mp_size;
1728 u32 old_alen = 0;
1729 BOOL mp_rebuilt = FALSE;
1730
1731 ntfs_debug("Extending mft data allocation.");
1732 mft_ni = NTFS_I(vol->mft_ino);
1733 /*
1734 * Determine the preferred allocation location, i.e. the last lcn of
1735 * the mft data attribute. The allocated size of the mft data
1736 * attribute cannot be zero so we are ok to do this.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001737 */
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001738 down_write(&mft_ni->runlist.lock);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001739 read_lock_irqsave(&mft_ni->size_lock, flags);
1740 ll = mft_ni->allocated_size;
1741 read_unlock_irqrestore(&mft_ni->size_lock, flags);
Anton Altaparmakovc0c1cc02005-03-07 21:43:38 +00001742 rl = ntfs_attr_find_vcn_nolock(mft_ni,
Anton Altaparmakov69b41e32005-10-04 14:01:14 +01001743 (ll - 1) >> vol->cluster_size_bits, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001744 if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001745 up_write(&mft_ni->runlist.lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001746 ntfs_error(vol->sb, "Failed to determine last allocated "
1747 "cluster of mft data attribute.");
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001748 if (!IS_ERR(rl))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001749 ret = -EIO;
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001750 else
Linus Torvalds1da177e2005-04-16 15:20:36 -07001751 ret = PTR_ERR(rl);
1752 return ret;
1753 }
1754 lcn = rl->lcn + rl->length;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001755 ntfs_debug("Last lcn of mft data attribute is 0x%llx.", (long long)lcn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001756 /* Minimum allocation is one mft record worth of clusters. */
1757 min_nr = vol->mft_record_size >> vol->cluster_size_bits;
1758 if (!min_nr)
1759 min_nr = 1;
1760 /* Want to allocate 16 mft records worth of clusters. */
1761 nr = vol->mft_record_size << 4 >> vol->cluster_size_bits;
1762 if (!nr)
1763 nr = min_nr;
1764 /* Ensure we do not go above 2^32-1 mft records. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001765 read_lock_irqsave(&mft_ni->size_lock, flags);
1766 ll = mft_ni->allocated_size;
1767 read_unlock_irqrestore(&mft_ni->size_lock, flags);
1768 if (unlikely((ll + (nr << vol->cluster_size_bits)) >>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001769 vol->mft_record_size_bits >= (1ll << 32))) {
1770 nr = min_nr;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001771 if (unlikely((ll + (nr << vol->cluster_size_bits)) >>
Linus Torvalds1da177e2005-04-16 15:20:36 -07001772 vol->mft_record_size_bits >= (1ll << 32))) {
1773 ntfs_warning(vol->sb, "Cannot allocate mft record "
1774 "because the maximum number of inodes "
1775 "(2^32) has already been reached.");
1776 up_write(&mft_ni->runlist.lock);
1777 return -ENOSPC;
1778 }
1779 }
1780 ntfs_debug("Trying mft data allocation with %s cluster count %lli.",
1781 nr > min_nr ? "default" : "minimal", (long long)nr);
1782 old_last_vcn = rl[1].vcn;
1783 do {
Anton Altaparmakovfc0fa7d2005-10-04 14:36:56 +01001784 rl2 = ntfs_cluster_alloc(vol, old_last_vcn, nr, lcn, MFT_ZONE,
1785 TRUE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001786 if (likely(!IS_ERR(rl2)))
1787 break;
1788 if (PTR_ERR(rl2) != -ENOSPC || nr == min_nr) {
1789 ntfs_error(vol->sb, "Failed to allocate the minimal "
1790 "number of clusters (%lli) for the "
1791 "mft data attribute.", (long long)nr);
1792 up_write(&mft_ni->runlist.lock);
1793 return PTR_ERR(rl2);
1794 }
1795 /*
1796 * There is not enough space to do the allocation, but there
1797 * might be enough space to do a minimal allocation so try that
1798 * before failing.
1799 */
1800 nr = min_nr;
1801 ntfs_debug("Retrying mft data allocation with minimal cluster "
1802 "count %lli.", (long long)nr);
1803 } while (1);
1804 rl = ntfs_runlists_merge(mft_ni->runlist.rl, rl2);
1805 if (IS_ERR(rl)) {
1806 up_write(&mft_ni->runlist.lock);
1807 ntfs_error(vol->sb, "Failed to merge runlists for mft data "
1808 "attribute.");
1809 if (ntfs_cluster_free_from_rl(vol, rl2)) {
1810 ntfs_error(vol->sb, "Failed to dealocate clusters "
1811 "from the mft data attribute.%s", es);
1812 NVolSetErrors(vol);
1813 }
1814 ntfs_free(rl2);
1815 return PTR_ERR(rl);
1816 }
1817 mft_ni->runlist.rl = rl;
Randy Dunlap89075472005-03-03 11:19:53 +00001818 ntfs_debug("Allocated %lli clusters.", (long long)nr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001819 /* Find the last run in the new runlist. */
1820 for (; rl[1].length; rl++)
1821 ;
1822 /* Update the attribute record as well. */
1823 mrec = map_mft_record(mft_ni);
1824 if (IS_ERR(mrec)) {
1825 ntfs_error(vol->sb, "Failed to map mft record.");
1826 ret = PTR_ERR(mrec);
1827 goto undo_alloc;
1828 }
1829 ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
1830 if (unlikely(!ctx)) {
1831 ntfs_error(vol->sb, "Failed to get search context.");
1832 ret = -ENOMEM;
1833 goto undo_alloc;
1834 }
1835 ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
1836 CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx);
1837 if (unlikely(ret)) {
1838 ntfs_error(vol->sb, "Failed to find last attribute extent of "
1839 "mft data attribute.");
1840 if (ret == -ENOENT)
1841 ret = -EIO;
1842 goto undo_alloc;
1843 }
1844 a = ctx->attr;
1845 ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
1846 /* Search back for the previous last allocated cluster of mft bitmap. */
1847 for (rl2 = rl; rl2 > mft_ni->runlist.rl; rl2--) {
1848 if (ll >= rl2->vcn)
1849 break;
1850 }
1851 BUG_ON(ll < rl2->vcn);
1852 BUG_ON(ll >= rl2->vcn + rl2->length);
1853 /* Get the size for the new mapping pairs array for this extent. */
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001854 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001855 if (unlikely(mp_size <= 0)) {
1856 ntfs_error(vol->sb, "Get size for mapping pairs failed for "
1857 "mft data attribute extent.");
1858 ret = mp_size;
1859 if (!ret)
1860 ret = -EIO;
1861 goto undo_alloc;
1862 }
1863 /* Expand the attribute record if necessary. */
1864 old_alen = le32_to_cpu(a->length);
1865 ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
1866 le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
1867 if (unlikely(ret)) {
1868 if (ret != -ENOSPC) {
1869 ntfs_error(vol->sb, "Failed to resize attribute "
1870 "record for mft data attribute.");
1871 goto undo_alloc;
1872 }
1873 // TODO: Deal with this by moving this extent to a new mft
1874 // record or by starting a new extent in a new mft record or by
1875 // moving other attributes out of this mft record.
1876 // Note: Use the special reserved mft records and ensure that
1877 // this extent is not required to find the mft record in
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00001878 // question. If no free special records left we would need to
1879 // move an existing record away, insert ours in its place, and
1880 // then place the moved record into the newly allocated space
1881 // and we would then need to update all references to this mft
1882 // record appropriately. This is rather complicated...
Linus Torvalds1da177e2005-04-16 15:20:36 -07001883 ntfs_error(vol->sb, "Not enough space in this mft record to "
1884 "accomodate extended mft data attribute "
1885 "extent. Cannot handle this yet.");
1886 ret = -EOPNOTSUPP;
1887 goto undo_alloc;
1888 }
1889 mp_rebuilt = TRUE;
1890 /* Generate the mapping pairs array directly into the attr record. */
1891 ret = ntfs_mapping_pairs_build(vol, (u8*)a +
1892 le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001893 mp_size, rl2, ll, -1, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001894 if (unlikely(ret)) {
1895 ntfs_error(vol->sb, "Failed to build mapping pairs array of "
1896 "mft data attribute.");
1897 goto undo_alloc;
1898 }
1899 /* Update the highest_vcn. */
1900 a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
1901 /*
1902 * We now have extended the mft data allocated_size by nr clusters.
1903 * Reflect this in the ntfs_inode structure and the attribute record.
1904 * @rl is the last (non-terminator) runlist element of mft data
1905 * attribute.
1906 */
1907 if (a->data.non_resident.lowest_vcn) {
1908 /*
1909 * We are not in the first attribute extent, switch to it, but
1910 * first ensure the changes will make it to disk later.
1911 */
1912 flush_dcache_mft_record_page(ctx->ntfs_ino);
1913 mark_mft_record_dirty(ctx->ntfs_ino);
1914 ntfs_attr_reinit_search_ctx(ctx);
1915 ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name,
1916 mft_ni->name_len, CASE_SENSITIVE, 0, NULL, 0,
1917 ctx);
1918 if (unlikely(ret)) {
1919 ntfs_error(vol->sb, "Failed to find first attribute "
1920 "extent of mft data attribute.");
1921 goto restore_undo_alloc;
1922 }
1923 a = ctx->attr;
1924 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001925 write_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001926 mft_ni->allocated_size += nr << vol->cluster_size_bits;
1927 a->data.non_resident.allocated_size =
1928 cpu_to_sle64(mft_ni->allocated_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001929 write_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001930 /* Ensure the changes make it to disk. */
1931 flush_dcache_mft_record_page(ctx->ntfs_ino);
1932 mark_mft_record_dirty(ctx->ntfs_ino);
1933 ntfs_attr_put_search_ctx(ctx);
1934 unmap_mft_record(mft_ni);
1935 up_write(&mft_ni->runlist.lock);
1936 ntfs_debug("Done.");
1937 return 0;
1938restore_undo_alloc:
1939 ntfs_attr_reinit_search_ctx(ctx);
1940 if (ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
1941 CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx)) {
1942 ntfs_error(vol->sb, "Failed to find last attribute extent of "
1943 "mft data attribute.%s", es);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001944 write_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945 mft_ni->allocated_size += nr << vol->cluster_size_bits;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00001946 write_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001947 ntfs_attr_put_search_ctx(ctx);
1948 unmap_mft_record(mft_ni);
1949 up_write(&mft_ni->runlist.lock);
1950 /*
1951 * The only thing that is now wrong is ->allocated_size of the
1952 * base attribute extent which chkdsk should be able to fix.
1953 */
1954 NVolSetErrors(vol);
1955 return ret;
1956 }
Anton Altaparmakov511bea52005-10-04 14:24:21 +01001957 ctx->attr->data.non_resident.highest_vcn =
1958 cpu_to_sle64(old_last_vcn - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001959undo_alloc:
Anton Altaparmakov511bea52005-10-04 14:24:21 +01001960 if (ntfs_cluster_free(mft_ni, old_last_vcn, -1, ctx) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961 ntfs_error(vol->sb, "Failed to free clusters from mft data "
1962 "attribute.%s", es);
1963 NVolSetErrors(vol);
1964 }
Anton Altaparmakov511bea52005-10-04 14:24:21 +01001965 a = ctx->attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001966 if (ntfs_rl_truncate_nolock(vol, &mft_ni->runlist, old_last_vcn)) {
1967 ntfs_error(vol->sb, "Failed to truncate mft data attribute "
1968 "runlist.%s", es);
1969 NVolSetErrors(vol);
1970 }
Anton Altaparmakov511bea52005-10-04 14:24:21 +01001971 if (mp_rebuilt && !IS_ERR(ctx->mrec)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001972 if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
1973 a->data.non_resident.mapping_pairs_offset),
1974 old_alen - le16_to_cpu(
1975 a->data.non_resident.mapping_pairs_offset),
Anton Altaparmakovfa3be9232005-06-25 17:15:36 +01001976 rl2, ll, -1, NULL)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001977 ntfs_error(vol->sb, "Failed to restore mapping pairs "
1978 "array.%s", es);
1979 NVolSetErrors(vol);
1980 }
1981 if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
1982 ntfs_error(vol->sb, "Failed to restore attribute "
1983 "record.%s", es);
1984 NVolSetErrors(vol);
1985 }
1986 flush_dcache_mft_record_page(ctx->ntfs_ino);
1987 mark_mft_record_dirty(ctx->ntfs_ino);
Anton Altaparmakov511bea52005-10-04 14:24:21 +01001988 } else if (IS_ERR(ctx->mrec)) {
1989 ntfs_error(vol->sb, "Failed to restore attribute search "
1990 "context.%s", es);
1991 NVolSetErrors(vol);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001992 }
1993 if (ctx)
1994 ntfs_attr_put_search_ctx(ctx);
1995 if (!IS_ERR(mrec))
1996 unmap_mft_record(mft_ni);
1997 up_write(&mft_ni->runlist.lock);
1998 return ret;
1999}
2000
2001/**
2002 * ntfs_mft_record_layout - layout an mft record into a memory buffer
2003 * @vol: volume to which the mft record will belong
2004 * @mft_no: mft reference specifying the mft record number
2005 * @m: destination buffer of size >= @vol->mft_record_size bytes
2006 *
2007 * Layout an empty, unused mft record with the mft record number @mft_no into
2008 * the buffer @m. The volume @vol is needed because the mft record structure
2009 * was modified in NTFS 3.1 so we need to know which volume version this mft
2010 * record will be used on.
2011 *
2012 * Return 0 on success and -errno on error.
2013 */
2014static int ntfs_mft_record_layout(const ntfs_volume *vol, const s64 mft_no,
2015 MFT_RECORD *m)
2016{
2017 ATTR_RECORD *a;
2018
2019 ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
2020 if (mft_no >= (1ll << 32)) {
2021 ntfs_error(vol->sb, "Mft record number 0x%llx exceeds "
2022 "maximum of 2^32.", (long long)mft_no);
2023 return -ERANGE;
2024 }
2025 /* Start by clearing the whole mft record to gives us a clean slate. */
2026 memset(m, 0, vol->mft_record_size);
2027 /* Aligned to 2-byte boundary. */
2028 if (vol->major_ver < 3 || (vol->major_ver == 3 && !vol->minor_ver))
2029 m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD_OLD) + 1) & ~1);
2030 else {
2031 m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD) + 1) & ~1);
2032 /*
2033 * Set the NTFS 3.1+ specific fields while we know that the
2034 * volume version is 3.1+.
2035 */
2036 m->reserved = 0;
2037 m->mft_record_number = cpu_to_le32((u32)mft_no);
2038 }
2039 m->magic = magic_FILE;
2040 if (vol->mft_record_size >= NTFS_BLOCK_SIZE)
2041 m->usa_count = cpu_to_le16(vol->mft_record_size /
2042 NTFS_BLOCK_SIZE + 1);
2043 else {
2044 m->usa_count = cpu_to_le16(1);
2045 ntfs_warning(vol->sb, "Sector size is bigger than mft record "
2046 "size. Setting usa_count to 1. If chkdsk "
2047 "reports this as corruption, please email "
2048 "linux-ntfs-dev@lists.sourceforge.net stating "
2049 "that you saw this message and that the "
Anton Altaparmakovb6ad6c52005-02-15 10:08:43 +00002050 "modified filesystem created was corrupt. "
Linus Torvalds1da177e2005-04-16 15:20:36 -07002051 "Thank you.");
2052 }
2053 /* Set the update sequence number to 1. */
2054 *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = cpu_to_le16(1);
2055 m->lsn = 0;
2056 m->sequence_number = cpu_to_le16(1);
2057 m->link_count = 0;
2058 /*
2059 * Place the attributes straight after the update sequence array,
2060 * aligned to 8-byte boundary.
2061 */
2062 m->attrs_offset = cpu_to_le16((le16_to_cpu(m->usa_ofs) +
2063 (le16_to_cpu(m->usa_count) << 1) + 7) & ~7);
2064 m->flags = 0;
2065 /*
2066 * Using attrs_offset plus eight bytes (for the termination attribute).
2067 * attrs_offset is already aligned to 8-byte boundary, so no need to
2068 * align again.
2069 */
2070 m->bytes_in_use = cpu_to_le32(le16_to_cpu(m->attrs_offset) + 8);
2071 m->bytes_allocated = cpu_to_le32(vol->mft_record_size);
2072 m->base_mft_record = 0;
2073 m->next_attr_instance = 0;
2074 /* Add the termination attribute. */
2075 a = (ATTR_RECORD*)((u8*)m + le16_to_cpu(m->attrs_offset));
2076 a->type = AT_END;
2077 a->length = 0;
2078 ntfs_debug("Done.");
2079 return 0;
2080}
2081
2082/**
2083 * ntfs_mft_record_format - format an mft record on an ntfs volume
2084 * @vol: volume on which to format the mft record
2085 * @mft_no: mft record number to format
2086 *
2087 * Format the mft record @mft_no in $MFT/$DATA, i.e. lay out an empty, unused
2088 * mft record into the appropriate place of the mft data attribute. This is
2089 * used when extending the mft data attribute.
2090 *
2091 * Return 0 on success and -errno on error.
2092 */
2093static int ntfs_mft_record_format(const ntfs_volume *vol, const s64 mft_no)
2094{
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002095 loff_t i_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002096 struct inode *mft_vi = vol->mft_ino;
2097 struct page *page;
2098 MFT_RECORD *m;
2099 pgoff_t index, end_index;
2100 unsigned int ofs;
2101 int err;
2102
2103 ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
2104 /*
2105 * The index into the page cache and the offset within the page cache
2106 * page of the wanted mft record.
2107 */
2108 index = mft_no << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
2109 ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
2110 /* The maximum valid index into the page cache for $MFT's data. */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002111 i_size = i_size_read(mft_vi);
2112 end_index = i_size >> PAGE_CACHE_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002113 if (unlikely(index >= end_index)) {
2114 if (unlikely(index > end_index || ofs + vol->mft_record_size >=
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002115 (i_size & ~PAGE_CACHE_MASK))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002116 ntfs_error(vol->sb, "Tried to format non-existing mft "
2117 "record 0x%llx.", (long long)mft_no);
2118 return -ENOENT;
2119 }
2120 }
2121 /* Read, map, and pin the page containing the mft record. */
2122 page = ntfs_map_page(mft_vi->i_mapping, index);
2123 if (unlikely(IS_ERR(page))) {
2124 ntfs_error(vol->sb, "Failed to map page containing mft record "
2125 "to format 0x%llx.", (long long)mft_no);
2126 return PTR_ERR(page);
2127 }
2128 lock_page(page);
2129 BUG_ON(!PageUptodate(page));
2130 ClearPageUptodate(page);
2131 m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
2132 err = ntfs_mft_record_layout(vol, mft_no, m);
2133 if (unlikely(err)) {
2134 ntfs_error(vol->sb, "Failed to layout mft record 0x%llx.",
2135 (long long)mft_no);
2136 SetPageUptodate(page);
2137 unlock_page(page);
2138 ntfs_unmap_page(page);
2139 return err;
2140 }
2141 flush_dcache_page(page);
2142 SetPageUptodate(page);
2143 unlock_page(page);
2144 /*
2145 * Make sure the mft record is written out to disk. We could use
2146 * ilookup5() to check if an inode is in icache and so on but this is
2147 * unnecessary as ntfs_writepage() will write the dirty record anyway.
2148 */
2149 mark_ntfs_record_dirty(page, ofs);
2150 ntfs_unmap_page(page);
2151 ntfs_debug("Done.");
2152 return 0;
2153}
2154
2155/**
2156 * ntfs_mft_record_alloc - allocate an mft record on an ntfs volume
2157 * @vol: [IN] volume on which to allocate the mft record
2158 * @mode: [IN] mode if want a file or directory, i.e. base inode or 0
2159 * @base_ni: [IN] open base inode if allocating an extent mft record or NULL
2160 * @mrec: [OUT] on successful return this is the mapped mft record
2161 *
2162 * Allocate an mft record in $MFT/$DATA of an open ntfs volume @vol.
2163 *
2164 * If @base_ni is NULL make the mft record a base mft record, i.e. a file or
2165 * direvctory inode, and allocate it at the default allocator position. In
2166 * this case @mode is the file mode as given to us by the caller. We in
2167 * particular use @mode to distinguish whether a file or a directory is being
2168 * created (S_IFDIR(mode) and S_IFREG(mode), respectively).
2169 *
2170 * If @base_ni is not NULL make the allocated mft record an extent record,
2171 * allocate it starting at the mft record after the base mft record and attach
2172 * the allocated and opened ntfs inode to the base inode @base_ni. In this
2173 * case @mode must be 0 as it is meaningless for extent inodes.
2174 *
2175 * You need to check the return value with IS_ERR(). If false, the function
2176 * was successful and the return value is the now opened ntfs inode of the
2177 * allocated mft record. *@mrec is then set to the allocated, mapped, pinned,
2178 * and locked mft record. If IS_ERR() is true, the function failed and the
2179 * error code is obtained from PTR_ERR(return value). *@mrec is undefined in
2180 * this case.
2181 *
2182 * Allocation strategy:
2183 *
2184 * To find a free mft record, we scan the mft bitmap for a zero bit. To
2185 * optimize this we start scanning at the place specified by @base_ni or if
2186 * @base_ni is NULL we start where we last stopped and we perform wrap around
2187 * when we reach the end. Note, we do not try to allocate mft records below
2188 * number 24 because numbers 0 to 15 are the defined system files anyway and 16
2189 * to 24 are special in that they are used for storing extension mft records
2190 * for the $DATA attribute of $MFT. This is required to avoid the possibility
2191 * of creating a runlist with a circular dependency which once written to disk
2192 * can never be read in again. Windows will only use records 16 to 24 for
2193 * normal files if the volume is completely out of space. We never use them
2194 * which means that when the volume is really out of space we cannot create any
2195 * more files while Windows can still create up to 8 small files. We can start
2196 * doing this at some later time, it does not matter much for now.
2197 *
2198 * When scanning the mft bitmap, we only search up to the last allocated mft
2199 * record. If there are no free records left in the range 24 to number of
2200 * allocated mft records, then we extend the $MFT/$DATA attribute in order to
2201 * create free mft records. We extend the allocated size of $MFT/$DATA by 16
2202 * records at a time or one cluster, if cluster size is above 16kiB. If there
2203 * is not sufficient space to do this, we try to extend by a single mft record
2204 * or one cluster, if cluster size is above the mft record size.
2205 *
2206 * No matter how many mft records we allocate, we initialize only the first
2207 * allocated mft record, incrementing mft data size and initialized size
2208 * accordingly, open an ntfs_inode for it and return it to the caller, unless
2209 * there are less than 24 mft records, in which case we allocate and initialize
2210 * mft records until we reach record 24 which we consider as the first free mft
2211 * record for use by normal files.
2212 *
2213 * If during any stage we overflow the initialized data in the mft bitmap, we
2214 * extend the initialized size (and data size) by 8 bytes, allocating another
2215 * cluster if required. The bitmap data size has to be at least equal to the
2216 * number of mft records in the mft, but it can be bigger, in which case the
2217 * superflous bits are padded with zeroes.
2218 *
2219 * Thus, when we return successfully (IS_ERR() is false), we will have:
2220 * - initialized / extended the mft bitmap if necessary,
2221 * - initialized / extended the mft data if necessary,
2222 * - set the bit corresponding to the mft record being allocated in the
2223 * mft bitmap,
2224 * - opened an ntfs_inode for the allocated mft record, and we will have
2225 * - returned the ntfs_inode as well as the allocated mapped, pinned, and
2226 * locked mft record.
2227 *
2228 * On error, the volume will be left in a consistent state and no record will
2229 * be allocated. If rolling back a partial operation fails, we may leave some
2230 * inconsistent metadata in which case we set NVolErrors() so the volume is
2231 * left dirty when unmounted.
2232 *
2233 * Note, this function cannot make use of most of the normal functions, like
2234 * for example for attribute resizing, etc, because when the run list overflows
2235 * the base mft record and an attribute list is used, it is very important that
2236 * the extension mft records used to store the $DATA attribute of $MFT can be
2237 * reached without having to read the information contained inside them, as
2238 * this would make it impossible to find them in the first place after the
2239 * volume is unmounted. $MFT/$BITMAP probably does not need to follow this
2240 * rule because the bitmap is not essential for finding the mft records, but on
2241 * the other hand, handling the bitmap in this special way would make life
2242 * easier because otherwise there might be circular invocations of functions
2243 * when reading the bitmap.
2244 */
2245ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
2246 ntfs_inode *base_ni, MFT_RECORD **mrec)
2247{
2248 s64 ll, bit, old_data_initialized, old_data_size;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002249 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002250 struct inode *vi;
2251 struct page *page;
2252 ntfs_inode *mft_ni, *mftbmp_ni, *ni;
2253 ntfs_attr_search_ctx *ctx;
2254 MFT_RECORD *m;
2255 ATTR_RECORD *a;
2256 pgoff_t index;
2257 unsigned int ofs;
2258 int err;
2259 le16 seq_no, usn;
2260 BOOL record_formatted = FALSE;
2261
2262 if (base_ni) {
2263 ntfs_debug("Entering (allocating an extent mft record for "
2264 "base mft record 0x%llx).",
2265 (long long)base_ni->mft_no);
2266 /* @mode and @base_ni are mutually exclusive. */
2267 BUG_ON(mode);
2268 } else
2269 ntfs_debug("Entering (allocating a base mft record).");
2270 if (mode) {
2271 /* @mode and @base_ni are mutually exclusive. */
2272 BUG_ON(base_ni);
2273 /* We only support creation of normal files and directories. */
2274 if (!S_ISREG(mode) && !S_ISDIR(mode))
2275 return ERR_PTR(-EOPNOTSUPP);
2276 }
2277 BUG_ON(!mrec);
2278 mft_ni = NTFS_I(vol->mft_ino);
2279 mftbmp_ni = NTFS_I(vol->mftbmp_ino);
2280 down_write(&vol->mftbmp_lock);
2281 bit = ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(vol, base_ni);
2282 if (bit >= 0) {
2283 ntfs_debug("Found and allocated free record (#1), bit 0x%llx.",
2284 (long long)bit);
2285 goto have_alloc_rec;
2286 }
2287 if (bit != -ENOSPC) {
2288 up_write(&vol->mftbmp_lock);
2289 return ERR_PTR(bit);
2290 }
2291 /*
2292 * No free mft records left. If the mft bitmap already covers more
2293 * than the currently used mft records, the next records are all free,
2294 * so we can simply allocate the first unused mft record.
2295 * Note: We also have to make sure that the mft bitmap at least covers
2296 * the first 24 mft records as they are special and whilst they may not
2297 * be in use, we do not allocate from them.
2298 */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002299 read_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002300 ll = mft_ni->initialized_size >> vol->mft_record_size_bits;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002301 read_unlock_irqrestore(&mft_ni->size_lock, flags);
2302 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
2303 old_data_initialized = mftbmp_ni->initialized_size;
2304 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
2305 if (old_data_initialized << 3 > ll && old_data_initialized > 3) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002306 bit = ll;
2307 if (bit < 24)
2308 bit = 24;
2309 if (unlikely(bit >= (1ll << 32)))
2310 goto max_err_out;
2311 ntfs_debug("Found free record (#2), bit 0x%llx.",
2312 (long long)bit);
2313 goto found_free_rec;
2314 }
2315 /*
2316 * The mft bitmap needs to be expanded until it covers the first unused
2317 * mft record that we can allocate.
2318 * Note: The smallest mft record we allocate is mft record 24.
2319 */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002320 bit = old_data_initialized << 3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002321 if (unlikely(bit >= (1ll << 32)))
2322 goto max_err_out;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002323 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
2324 old_data_size = mftbmp_ni->allocated_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002325 ntfs_debug("Status of mftbmp before extension: allocated_size 0x%llx, "
2326 "data_size 0x%llx, initialized_size 0x%llx.",
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002327 (long long)old_data_size,
2328 (long long)i_size_read(vol->mftbmp_ino),
2329 (long long)old_data_initialized);
2330 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
2331 if (old_data_initialized + 8 > old_data_size) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002332 /* Need to extend bitmap by one more cluster. */
2333 ntfs_debug("mftbmp: initialized_size + 8 > allocated_size.");
2334 err = ntfs_mft_bitmap_extend_allocation_nolock(vol);
2335 if (unlikely(err)) {
2336 up_write(&vol->mftbmp_lock);
2337 goto err_out;
2338 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002339#ifdef DEBUG
2340 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002341 ntfs_debug("Status of mftbmp after allocation extension: "
2342 "allocated_size 0x%llx, data_size 0x%llx, "
2343 "initialized_size 0x%llx.",
2344 (long long)mftbmp_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002345 (long long)i_size_read(vol->mftbmp_ino),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002346 (long long)mftbmp_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002347 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
2348#endif /* DEBUG */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002349 }
2350 /*
2351 * We now have sufficient allocated space, extend the initialized_size
2352 * as well as the data_size if necessary and fill the new space with
2353 * zeroes.
2354 */
2355 err = ntfs_mft_bitmap_extend_initialized_nolock(vol);
2356 if (unlikely(err)) {
2357 up_write(&vol->mftbmp_lock);
2358 goto err_out;
2359 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002360#ifdef DEBUG
2361 read_lock_irqsave(&mftbmp_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362 ntfs_debug("Status of mftbmp after initialized extention: "
2363 "allocated_size 0x%llx, data_size 0x%llx, "
2364 "initialized_size 0x%llx.",
2365 (long long)mftbmp_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002366 (long long)i_size_read(vol->mftbmp_ino),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002367 (long long)mftbmp_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002368 read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
2369#endif /* DEBUG */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002370 ntfs_debug("Found free record (#3), bit 0x%llx.", (long long)bit);
2371found_free_rec:
2372 /* @bit is the found free mft record, allocate it in the mft bitmap. */
2373 ntfs_debug("At found_free_rec.");
2374 err = ntfs_bitmap_set_bit(vol->mftbmp_ino, bit);
2375 if (unlikely(err)) {
2376 ntfs_error(vol->sb, "Failed to allocate bit in mft bitmap.");
2377 up_write(&vol->mftbmp_lock);
2378 goto err_out;
2379 }
2380 ntfs_debug("Set bit 0x%llx in mft bitmap.", (long long)bit);
2381have_alloc_rec:
2382 /*
2383 * The mft bitmap is now uptodate. Deal with mft data attribute now.
2384 * Note, we keep hold of the mft bitmap lock for writing until all
2385 * modifications to the mft data attribute are complete, too, as they
2386 * will impact decisions for mft bitmap and mft record allocation done
2387 * by a parallel allocation and if the lock is not maintained a
2388 * parallel allocation could allocate the same mft record as this one.
2389 */
2390 ll = (bit + 1) << vol->mft_record_size_bits;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002391 read_lock_irqsave(&mft_ni->size_lock, flags);
2392 old_data_initialized = mft_ni->initialized_size;
2393 read_unlock_irqrestore(&mft_ni->size_lock, flags);
2394 if (ll <= old_data_initialized) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002395 ntfs_debug("Allocated mft record already initialized.");
2396 goto mft_rec_already_initialized;
2397 }
2398 ntfs_debug("Initializing allocated mft record.");
2399 /*
2400 * The mft record is outside the initialized data. Extend the mft data
2401 * attribute until it covers the allocated record. The loop is only
2402 * actually traversed more than once when a freshly formatted volume is
2403 * first written to so it optimizes away nicely in the common case.
2404 */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002405 read_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002406 ntfs_debug("Status of mft data before extension: "
2407 "allocated_size 0x%llx, data_size 0x%llx, "
2408 "initialized_size 0x%llx.",
Anton Altaparmakov3834c3f2005-01-13 11:04:39 +00002409 (long long)mft_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002410 (long long)i_size_read(vol->mft_ino),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002411 (long long)mft_ni->initialized_size);
Anton Altaparmakov3834c3f2005-01-13 11:04:39 +00002412 while (ll > mft_ni->allocated_size) {
2413 read_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002414 err = ntfs_mft_data_extend_allocation_nolock(vol);
2415 if (unlikely(err)) {
2416 ntfs_error(vol->sb, "Failed to extend mft data "
2417 "allocation.");
2418 goto undo_mftbmp_alloc_nolock;
2419 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002420 read_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421 ntfs_debug("Status of mft data after allocation extension: "
2422 "allocated_size 0x%llx, data_size 0x%llx, "
2423 "initialized_size 0x%llx.",
2424 (long long)mft_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002425 (long long)i_size_read(vol->mft_ino),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002426 (long long)mft_ni->initialized_size);
2427 }
Anton Altaparmakov3834c3f2005-01-13 11:04:39 +00002428 read_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002429 /*
2430 * Extend mft data initialized size (and data size of course) to reach
2431 * the allocated mft record, formatting the mft records allong the way.
2432 * Note: We only modify the ntfs_inode structure as that is all that is
2433 * needed by ntfs_mft_record_format(). We will update the attribute
2434 * record itself in one fell swoop later on.
2435 */
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002436 write_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002437 old_data_initialized = mft_ni->initialized_size;
2438 old_data_size = vol->mft_ino->i_size;
2439 while (ll > mft_ni->initialized_size) {
2440 s64 new_initialized_size, mft_no;
2441
2442 new_initialized_size = mft_ni->initialized_size +
2443 vol->mft_record_size;
2444 mft_no = mft_ni->initialized_size >> vol->mft_record_size_bits;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002445 if (new_initialized_size > i_size_read(vol->mft_ino))
2446 i_size_write(vol->mft_ino, new_initialized_size);
2447 write_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002448 ntfs_debug("Initializing mft record 0x%llx.",
2449 (long long)mft_no);
2450 err = ntfs_mft_record_format(vol, mft_no);
2451 if (unlikely(err)) {
2452 ntfs_error(vol->sb, "Failed to format mft record.");
2453 goto undo_data_init;
2454 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002455 write_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002456 mft_ni->initialized_size = new_initialized_size;
2457 }
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002458 write_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002459 record_formatted = TRUE;
2460 /* Update the mft data attribute record to reflect the new sizes. */
2461 m = map_mft_record(mft_ni);
2462 if (IS_ERR(m)) {
2463 ntfs_error(vol->sb, "Failed to map mft record.");
2464 err = PTR_ERR(m);
2465 goto undo_data_init;
2466 }
2467 ctx = ntfs_attr_get_search_ctx(mft_ni, m);
2468 if (unlikely(!ctx)) {
2469 ntfs_error(vol->sb, "Failed to get search context.");
2470 err = -ENOMEM;
2471 unmap_mft_record(mft_ni);
2472 goto undo_data_init;
2473 }
2474 err = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
2475 CASE_SENSITIVE, 0, NULL, 0, ctx);
2476 if (unlikely(err)) {
2477 ntfs_error(vol->sb, "Failed to find first attribute extent of "
2478 "mft data attribute.");
2479 ntfs_attr_put_search_ctx(ctx);
2480 unmap_mft_record(mft_ni);
2481 goto undo_data_init;
2482 }
2483 a = ctx->attr;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002484 read_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002485 a->data.non_resident.initialized_size =
2486 cpu_to_sle64(mft_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002487 a->data.non_resident.data_size =
2488 cpu_to_sle64(i_size_read(vol->mft_ino));
2489 read_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002490 /* Ensure the changes make it to disk. */
2491 flush_dcache_mft_record_page(ctx->ntfs_ino);
2492 mark_mft_record_dirty(ctx->ntfs_ino);
2493 ntfs_attr_put_search_ctx(ctx);
2494 unmap_mft_record(mft_ni);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002495 read_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002496 ntfs_debug("Status of mft data after mft record initialization: "
2497 "allocated_size 0x%llx, data_size 0x%llx, "
2498 "initialized_size 0x%llx.",
2499 (long long)mft_ni->allocated_size,
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002500 (long long)i_size_read(vol->mft_ino),
Linus Torvalds1da177e2005-04-16 15:20:36 -07002501 (long long)mft_ni->initialized_size);
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002502 BUG_ON(i_size_read(vol->mft_ino) > mft_ni->allocated_size);
2503 BUG_ON(mft_ni->initialized_size > i_size_read(vol->mft_ino));
2504 read_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002505mft_rec_already_initialized:
2506 /*
2507 * We can finally drop the mft bitmap lock as the mft data attribute
2508 * has been fully updated. The only disparity left is that the
2509 * allocated mft record still needs to be marked as in use to match the
2510 * set bit in the mft bitmap but this is actually not a problem since
2511 * this mft record is not referenced from anywhere yet and the fact
2512 * that it is allocated in the mft bitmap means that no-one will try to
2513 * allocate it either.
2514 */
2515 up_write(&vol->mftbmp_lock);
2516 /*
2517 * We now have allocated and initialized the mft record. Calculate the
2518 * index of and the offset within the page cache page the record is in.
2519 */
2520 index = bit << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
2521 ofs = (bit << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
2522 /* Read, map, and pin the page containing the mft record. */
2523 page = ntfs_map_page(vol->mft_ino->i_mapping, index);
2524 if (unlikely(IS_ERR(page))) {
2525 ntfs_error(vol->sb, "Failed to map page containing allocated "
2526 "mft record 0x%llx.", (long long)bit);
2527 err = PTR_ERR(page);
2528 goto undo_mftbmp_alloc;
2529 }
2530 lock_page(page);
2531 BUG_ON(!PageUptodate(page));
2532 ClearPageUptodate(page);
2533 m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
2534 /* If we just formatted the mft record no need to do it again. */
2535 if (!record_formatted) {
2536 /* Sanity check that the mft record is really not in use. */
2537 if (ntfs_is_file_record(m->magic) &&
2538 (m->flags & MFT_RECORD_IN_USE)) {
2539 ntfs_error(vol->sb, "Mft record 0x%llx was marked "
2540 "free in mft bitmap but is marked "
2541 "used itself. Corrupt filesystem. "
2542 "Unmount and run chkdsk.",
2543 (long long)bit);
2544 err = -EIO;
2545 SetPageUptodate(page);
2546 unlock_page(page);
2547 ntfs_unmap_page(page);
2548 NVolSetErrors(vol);
2549 goto undo_mftbmp_alloc;
2550 }
2551 /*
2552 * We need to (re-)format the mft record, preserving the
2553 * sequence number if it is not zero as well as the update
2554 * sequence number if it is not zero or -1 (0xffff). This
2555 * means we do not need to care whether or not something went
2556 * wrong with the previous mft record.
2557 */
2558 seq_no = m->sequence_number;
2559 usn = *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs));
2560 err = ntfs_mft_record_layout(vol, bit, m);
2561 if (unlikely(err)) {
2562 ntfs_error(vol->sb, "Failed to layout allocated mft "
2563 "record 0x%llx.", (long long)bit);
2564 SetPageUptodate(page);
2565 unlock_page(page);
2566 ntfs_unmap_page(page);
2567 goto undo_mftbmp_alloc;
2568 }
2569 if (seq_no)
2570 m->sequence_number = seq_no;
2571 if (usn && le16_to_cpu(usn) != 0xffff)
2572 *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = usn;
2573 }
2574 /* Set the mft record itself in use. */
2575 m->flags |= MFT_RECORD_IN_USE;
2576 if (S_ISDIR(mode))
2577 m->flags |= MFT_RECORD_IS_DIRECTORY;
2578 flush_dcache_page(page);
2579 SetPageUptodate(page);
2580 if (base_ni) {
2581 /*
2582 * Setup the base mft record in the extent mft record. This
2583 * completes initialization of the allocated extent mft record
2584 * and we can simply use it with map_extent_mft_record().
2585 */
2586 m->base_mft_record = MK_LE_MREF(base_ni->mft_no,
2587 base_ni->seq_no);
2588 /*
2589 * Allocate an extent inode structure for the new mft record,
2590 * attach it to the base inode @base_ni and map, pin, and lock
2591 * its, i.e. the allocated, mft record.
2592 */
2593 m = map_extent_mft_record(base_ni, bit, &ni);
2594 if (IS_ERR(m)) {
2595 ntfs_error(vol->sb, "Failed to map allocated extent "
2596 "mft record 0x%llx.", (long long)bit);
2597 err = PTR_ERR(m);
2598 /* Set the mft record itself not in use. */
2599 m->flags &= cpu_to_le16(
2600 ~le16_to_cpu(MFT_RECORD_IN_USE));
2601 flush_dcache_page(page);
2602 /* Make sure the mft record is written out to disk. */
2603 mark_ntfs_record_dirty(page, ofs);
2604 unlock_page(page);
2605 ntfs_unmap_page(page);
2606 goto undo_mftbmp_alloc;
2607 }
2608 /*
2609 * Make sure the allocated mft record is written out to disk.
2610 * No need to set the inode dirty because the caller is going
2611 * to do that anyway after finishing with the new extent mft
2612 * record (e.g. at a minimum a new attribute will be added to
2613 * the mft record.
2614 */
2615 mark_ntfs_record_dirty(page, ofs);
2616 unlock_page(page);
2617 /*
2618 * Need to unmap the page since map_extent_mft_record() mapped
2619 * it as well so we have it mapped twice at the moment.
2620 */
2621 ntfs_unmap_page(page);
2622 } else {
2623 /*
2624 * Allocate a new VFS inode and set it up. NOTE: @vi->i_nlink
2625 * is set to 1 but the mft record->link_count is 0. The caller
2626 * needs to bear this in mind.
2627 */
2628 vi = new_inode(vol->sb);
2629 if (unlikely(!vi)) {
2630 err = -ENOMEM;
2631 /* Set the mft record itself not in use. */
2632 m->flags &= cpu_to_le16(
2633 ~le16_to_cpu(MFT_RECORD_IN_USE));
2634 flush_dcache_page(page);
2635 /* Make sure the mft record is written out to disk. */
2636 mark_ntfs_record_dirty(page, ofs);
2637 unlock_page(page);
2638 ntfs_unmap_page(page);
2639 goto undo_mftbmp_alloc;
2640 }
2641 vi->i_ino = bit;
2642 /*
2643 * This is the optimal IO size (for stat), not the fs block
2644 * size.
2645 */
2646 vi->i_blksize = PAGE_CACHE_SIZE;
2647 /*
2648 * This is for checking whether an inode has changed w.r.t. a
2649 * file so that the file can be updated if necessary (compare
2650 * with f_version).
2651 */
2652 vi->i_version = 1;
2653
2654 /* The owner and group come from the ntfs volume. */
2655 vi->i_uid = vol->uid;
2656 vi->i_gid = vol->gid;
2657
2658 /* Initialize the ntfs specific part of @vi. */
2659 ntfs_init_big_inode(vi);
2660 ni = NTFS_I(vi);
2661 /*
2662 * Set the appropriate mode, attribute type, and name. For
2663 * directories, also setup the index values to the defaults.
2664 */
2665 if (S_ISDIR(mode)) {
2666 vi->i_mode = S_IFDIR | S_IRWXUGO;
2667 vi->i_mode &= ~vol->dmask;
2668
2669 NInoSetMstProtected(ni);
2670 ni->type = AT_INDEX_ALLOCATION;
2671 ni->name = I30;
2672 ni->name_len = 4;
2673
2674 ni->itype.index.block_size = 4096;
2675 ni->itype.index.block_size_bits = generic_ffs(4096) - 1;
2676 ni->itype.index.collation_rule = COLLATION_FILE_NAME;
2677 if (vol->cluster_size <= ni->itype.index.block_size) {
2678 ni->itype.index.vcn_size = vol->cluster_size;
2679 ni->itype.index.vcn_size_bits =
2680 vol->cluster_size_bits;
2681 } else {
2682 ni->itype.index.vcn_size = vol->sector_size;
2683 ni->itype.index.vcn_size_bits =
2684 vol->sector_size_bits;
2685 }
2686 } else {
2687 vi->i_mode = S_IFREG | S_IRWXUGO;
2688 vi->i_mode &= ~vol->fmask;
2689
2690 ni->type = AT_DATA;
2691 ni->name = NULL;
2692 ni->name_len = 0;
2693 }
2694 if (IS_RDONLY(vi))
2695 vi->i_mode &= ~S_IWUGO;
2696
2697 /* Set the inode times to the current time. */
2698 vi->i_atime = vi->i_mtime = vi->i_ctime =
2699 current_fs_time(vi->i_sb);
2700 /*
2701 * Set the file size to 0, the ntfs inode sizes are set to 0 by
2702 * the call to ntfs_init_big_inode() below.
2703 */
2704 vi->i_size = 0;
2705 vi->i_blocks = 0;
2706
2707 /* Set the sequence number. */
2708 vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
2709 /*
2710 * Manually map, pin, and lock the mft record as we already
2711 * have its page mapped and it is very easy to do.
2712 */
2713 atomic_inc(&ni->count);
2714 down(&ni->mrec_lock);
2715 ni->page = page;
2716 ni->page_ofs = ofs;
2717 /*
2718 * Make sure the allocated mft record is written out to disk.
2719 * NOTE: We do not set the ntfs inode dirty because this would
2720 * fail in ntfs_write_inode() because the inode does not have a
2721 * standard information attribute yet. Also, there is no need
2722 * to set the inode dirty because the caller is going to do
2723 * that anyway after finishing with the new mft record (e.g. at
2724 * a minimum some new attributes will be added to the mft
2725 * record.
2726 */
2727 mark_ntfs_record_dirty(page, ofs);
2728 unlock_page(page);
2729
2730 /* Add the inode to the inode hash for the superblock. */
2731 insert_inode_hash(vi);
2732
2733 /* Update the default mft allocation position. */
2734 vol->mft_data_pos = bit + 1;
2735 }
2736 /*
2737 * Return the opened, allocated inode of the allocated mft record as
2738 * well as the mapped, pinned, and locked mft record.
2739 */
2740 ntfs_debug("Returning opened, allocated %sinode 0x%llx.",
2741 base_ni ? "extent " : "", (long long)bit);
2742 *mrec = m;
2743 return ni;
2744undo_data_init:
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002745 write_lock_irqsave(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002746 mft_ni->initialized_size = old_data_initialized;
Anton Altaparmakov07a4e2d2005-01-12 13:08:26 +00002747 i_size_write(vol->mft_ino, old_data_size);
2748 write_unlock_irqrestore(&mft_ni->size_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002749 goto undo_mftbmp_alloc_nolock;
2750undo_mftbmp_alloc:
2751 down_write(&vol->mftbmp_lock);
2752undo_mftbmp_alloc_nolock:
2753 if (ntfs_bitmap_clear_bit(vol->mftbmp_ino, bit)) {
2754 ntfs_error(vol->sb, "Failed to clear bit in mft bitmap.%s", es);
2755 NVolSetErrors(vol);
2756 }
2757 up_write(&vol->mftbmp_lock);
2758err_out:
2759 return ERR_PTR(err);
2760max_err_out:
2761 ntfs_warning(vol->sb, "Cannot allocate mft record because the maximum "
2762 "number of inodes (2^32) has already been reached.");
2763 up_write(&vol->mftbmp_lock);
2764 return ERR_PTR(-ENOSPC);
2765}
2766
2767/**
2768 * ntfs_extent_mft_record_free - free an extent mft record on an ntfs volume
2769 * @ni: ntfs inode of the mapped extent mft record to free
2770 * @m: mapped extent mft record of the ntfs inode @ni
2771 *
2772 * Free the mapped extent mft record @m of the extent ntfs inode @ni.
2773 *
2774 * Note that this function unmaps the mft record and closes and destroys @ni
2775 * internally and hence you cannot use either @ni nor @m any more after this
2776 * function returns success.
2777 *
2778 * On success return 0 and on error return -errno. @ni and @m are still valid
2779 * in this case and have not been freed.
2780 *
2781 * For some errors an error message is displayed and the success code 0 is
2782 * returned and the volume is then left dirty on umount. This makes sense in
2783 * case we could not rollback the changes that were already done since the
2784 * caller no longer wants to reference this mft record so it does not matter to
2785 * the caller if something is wrong with it as long as it is properly detached
2786 * from the base inode.
2787 */
2788int ntfs_extent_mft_record_free(ntfs_inode *ni, MFT_RECORD *m)
2789{
2790 unsigned long mft_no = ni->mft_no;
2791 ntfs_volume *vol = ni->vol;
2792 ntfs_inode *base_ni;
2793 ntfs_inode **extent_nis;
2794 int i, err;
2795 le16 old_seq_no;
2796 u16 seq_no;
2797
2798 BUG_ON(NInoAttr(ni));
2799 BUG_ON(ni->nr_extents != -1);
2800
2801 down(&ni->extent_lock);
2802 base_ni = ni->ext.base_ntfs_ino;
2803 up(&ni->extent_lock);
2804
2805 BUG_ON(base_ni->nr_extents <= 0);
2806
2807 ntfs_debug("Entering for extent inode 0x%lx, base inode 0x%lx.\n",
2808 mft_no, base_ni->mft_no);
2809
2810 down(&base_ni->extent_lock);
2811
2812 /* Make sure we are holding the only reference to the extent inode. */
2813 if (atomic_read(&ni->count) > 2) {
2814 ntfs_error(vol->sb, "Tried to free busy extent inode 0x%lx, "
2815 "not freeing.", base_ni->mft_no);
2816 up(&base_ni->extent_lock);
2817 return -EBUSY;
2818 }
2819
2820 /* Dissociate the ntfs inode from the base inode. */
2821 extent_nis = base_ni->ext.extent_ntfs_inos;
2822 err = -ENOENT;
2823 for (i = 0; i < base_ni->nr_extents; i++) {
2824 if (ni != extent_nis[i])
2825 continue;
2826 extent_nis += i;
2827 base_ni->nr_extents--;
2828 memmove(extent_nis, extent_nis + 1, (base_ni->nr_extents - i) *
2829 sizeof(ntfs_inode*));
2830 err = 0;
2831 break;
2832 }
2833
2834 up(&base_ni->extent_lock);
2835
2836 if (unlikely(err)) {
2837 ntfs_error(vol->sb, "Extent inode 0x%lx is not attached to "
2838 "its base inode 0x%lx.", mft_no,
2839 base_ni->mft_no);
2840 BUG();
2841 }
2842
2843 /*
2844 * The extent inode is no longer attached to the base inode so no one
2845 * can get a reference to it any more.
2846 */
2847
2848 /* Mark the mft record as not in use. */
2849 m->flags &= const_cpu_to_le16(~const_le16_to_cpu(MFT_RECORD_IN_USE));
2850
2851 /* Increment the sequence number, skipping zero, if it is not zero. */
2852 old_seq_no = m->sequence_number;
2853 seq_no = le16_to_cpu(old_seq_no);
2854 if (seq_no == 0xffff)
2855 seq_no = 1;
2856 else if (seq_no)
2857 seq_no++;
2858 m->sequence_number = cpu_to_le16(seq_no);
2859
2860 /*
2861 * Set the ntfs inode dirty and write it out. We do not need to worry
2862 * about the base inode here since whatever caused the extent mft
2863 * record to be freed is guaranteed to do it already.
2864 */
2865 NInoSetDirty(ni);
2866 err = write_mft_record(ni, m, 0);
2867 if (unlikely(err)) {
2868 ntfs_error(vol->sb, "Failed to write mft record 0x%lx, not "
2869 "freeing.", mft_no);
2870 goto rollback;
2871 }
2872rollback_error:
2873 /* Unmap and throw away the now freed extent inode. */
2874 unmap_extent_mft_record(ni);
2875 ntfs_clear_extent_inode(ni);
2876
2877 /* Clear the bit in the $MFT/$BITMAP corresponding to this record. */
2878 down_write(&vol->mftbmp_lock);
2879 err = ntfs_bitmap_clear_bit(vol->mftbmp_ino, mft_no);
2880 up_write(&vol->mftbmp_lock);
2881 if (unlikely(err)) {
2882 /*
2883 * The extent inode is gone but we failed to deallocate it in
2884 * the mft bitmap. Just emit a warning and leave the volume
2885 * dirty on umount.
2886 */
2887 ntfs_error(vol->sb, "Failed to clear bit in mft bitmap.%s", es);
2888 NVolSetErrors(vol);
2889 }
2890 return 0;
2891rollback:
2892 /* Rollback what we did... */
2893 down(&base_ni->extent_lock);
2894 extent_nis = base_ni->ext.extent_ntfs_inos;
2895 if (!(base_ni->nr_extents & 3)) {
2896 int new_size = (base_ni->nr_extents + 4) * sizeof(ntfs_inode*);
2897
2898 extent_nis = (ntfs_inode**)kmalloc(new_size, GFP_NOFS);
2899 if (unlikely(!extent_nis)) {
2900 ntfs_error(vol->sb, "Failed to allocate internal "
2901 "buffer during rollback.%s", es);
2902 up(&base_ni->extent_lock);
2903 NVolSetErrors(vol);
2904 goto rollback_error;
2905 }
2906 if (base_ni->nr_extents) {
2907 BUG_ON(!base_ni->ext.extent_ntfs_inos);
2908 memcpy(extent_nis, base_ni->ext.extent_ntfs_inos,
2909 new_size - 4 * sizeof(ntfs_inode*));
2910 kfree(base_ni->ext.extent_ntfs_inos);
2911 }
2912 base_ni->ext.extent_ntfs_inos = extent_nis;
2913 }
2914 m->flags |= MFT_RECORD_IN_USE;
2915 m->sequence_number = old_seq_no;
2916 extent_nis[base_ni->nr_extents++] = ni;
2917 up(&base_ni->extent_lock);
2918 mark_mft_record_dirty(ni);
2919 return err;
2920}
2921#endif /* NTFS_RW */