2 * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project.
4 * Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
5 * Copyright (c) 2002 Richard Russon
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.
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.
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
23 #include <linux/buffer_head.h>
24 #include <linux/sched.h>
25 #include <linux/slab.h>
26 #include <linux/swap.h>
27 #include <linux/writeback.h>
39 * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
40 * @ni: ntfs inode for which to map (part of) a runlist
41 * @vcn: map runlist part containing this vcn
42 * @ctx: active attribute search context if present or NULL if not
44 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
46 * If @ctx is specified, it is an active search context of @ni and its base mft
47 * record. This is needed when ntfs_map_runlist_nolock() encounters unmapped
48 * runlist fragments and allows their mapping. If you do not have the mft
49 * record mapped, you can specify @ctx as NULL and ntfs_map_runlist_nolock()
50 * will perform the necessary mapping and unmapping.
52 * Note, ntfs_map_runlist_nolock() saves the state of @ctx on entry and
53 * restores it before returning. Thus, @ctx will be left pointing to the same
54 * attribute on return as on entry. However, the actual pointers in @ctx may
55 * point to different memory locations on return, so you must remember to reset
56 * any cached pointers from the @ctx, i.e. after the call to
57 * ntfs_map_runlist_nolock(), you will probably want to do:
60 * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that
61 * you cache ctx->mrec in a variable @m of type MFT_RECORD *.
63 * Return 0 on success and -errno on error. There is one special error code
64 * which is not an error as such. This is -ENOENT. It means that @vcn is out
65 * of bounds of the runlist.
67 * Note the runlist can be NULL after this function returns if @vcn is zero and
68 * the attribute has zero allocated size, i.e. there simply is no runlist.
70 * WARNING: If @ctx is supplied, regardless of whether success or failure is
71 * returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx
72 * is no longer valid, i.e. you need to either call
73 * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
74 * In that case PTR_ERR(@ctx->mrec) will give you the error code for
75 * why the mapping of the old inode failed.
77 * Locking: - The runlist described by @ni must be locked for writing on entry
78 * and is locked on return. Note the runlist will be modified.
79 * - If @ctx is NULL, the base mft record of @ni must not be mapped on
80 * entry and it will be left unmapped on return.
81 * - If @ctx is not NULL, the base mft record must be mapped on entry
82 * and it will be left mapped on return.
84 int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn, ntfs_attr_search_ctx *ctx)
92 struct page *put_this_page = NULL;
94 bool ctx_is_temporary, ctx_needs_reset;
95 ntfs_attr_search_ctx old_ctx = { NULL, };
97 ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
98 (unsigned long long)vcn);
102 base_ni = ni->ext.base_ntfs_ino;
104 ctx_is_temporary = ctx_needs_reset = true;
105 m = map_mft_record(base_ni);
108 ctx = ntfs_attr_get_search_ctx(base_ni, m);
109 if (unlikely(!ctx)) {
114 VCN allocated_size_vcn;
116 BUG_ON(IS_ERR(ctx->mrec));
118 BUG_ON(!a->non_resident);
119 ctx_is_temporary = false;
120 end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
121 read_lock_irqsave(&ni->size_lock, flags);
122 allocated_size_vcn = ni->allocated_size >>
123 ni->vol->cluster_size_bits;
124 read_unlock_irqrestore(&ni->size_lock, flags);
125 if (!a->data.non_resident.lowest_vcn && end_vcn <= 0)
126 end_vcn = allocated_size_vcn - 1;
128 * If we already have the attribute extent containing @vcn in
129 * @ctx, no need to look it up again. We slightly cheat in
130 * that if vcn exceeds the allocated size, we will refuse to
131 * map the runlist below, so there is definitely no need to get
132 * the right attribute extent.
134 if (vcn >= allocated_size_vcn || (a->type == ni->type &&
135 a->name_length == ni->name_len &&
136 !memcmp((u8*)a + le16_to_cpu(a->name_offset),
137 ni->name, ni->name_len) &&
138 sle64_to_cpu(a->data.non_resident.lowest_vcn)
139 <= vcn && end_vcn >= vcn))
140 ctx_needs_reset = false;
142 /* Save the old search context. */
145 * If the currently mapped (extent) inode is not the
146 * base inode we will unmap it when we reinitialize the
147 * search context which means we need to get a
148 * reference to the page containing the mapped mft
149 * record so we do not accidentally drop changes to the
150 * mft record when it has not been marked dirty yet.
152 if (old_ctx.base_ntfs_ino && old_ctx.ntfs_ino !=
153 old_ctx.base_ntfs_ino) {
154 put_this_page = old_ctx.ntfs_ino->page;
155 get_page(put_this_page);
158 * Reinitialize the search context so we can lookup the
159 * needed attribute extent.
161 ntfs_attr_reinit_search_ctx(ctx);
162 ctx_needs_reset = true;
165 if (ctx_needs_reset) {
166 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
167 CASE_SENSITIVE, vcn, NULL, 0, ctx);
173 BUG_ON(!ctx->attr->non_resident);
177 * Only decompress the mapping pairs if @vcn is inside it. Otherwise
178 * we get into problems when we try to map an out of bounds vcn because
179 * we then try to map the already mapped runlist fragment and
180 * ntfs_mapping_pairs_decompress() fails.
182 end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn) + 1;
183 if (unlikely(vcn && vcn >= end_vcn)) {
187 rl = ntfs_mapping_pairs_decompress(ni->vol, a, ni->runlist.rl);
193 if (ctx_is_temporary) {
195 ntfs_attr_put_search_ctx(ctx);
196 unmap_mft_record(base_ni);
197 } else if (ctx_needs_reset) {
199 * If there is no attribute list, restoring the search context
200 * is accomplished simply by copying the saved context back over
201 * the caller supplied context. If there is an attribute list,
202 * things are more complicated as we need to deal with mapping
203 * of mft records and resulting potential changes in pointers.
205 if (NInoAttrList(base_ni)) {
207 * If the currently mapped (extent) inode is not the
208 * one we had before, we need to unmap it and map the
211 if (ctx->ntfs_ino != old_ctx.ntfs_ino) {
213 * If the currently mapped inode is not the
214 * base inode, unmap it.
216 if (ctx->base_ntfs_ino && ctx->ntfs_ino !=
217 ctx->base_ntfs_ino) {
218 unmap_extent_mft_record(ctx->ntfs_ino);
219 ctx->mrec = ctx->base_mrec;
223 * If the old mapped inode is not the base
226 if (old_ctx.base_ntfs_ino &&
228 old_ctx.base_ntfs_ino) {
230 ctx->mrec = map_mft_record(
233 * Something bad has happened. If out
234 * of memory retry till it succeeds.
235 * Any other errors are fatal and we
236 * return the error code in ctx->mrec.
237 * Let the caller deal with it... We
238 * just need to fudge things so the
239 * caller can reinit and/or put the
240 * search context safely.
242 if (IS_ERR(ctx->mrec)) {
243 if (PTR_ERR(ctx->mrec) ==
254 /* Update the changed pointers in the saved context. */
255 if (ctx->mrec != old_ctx.mrec) {
256 if (!IS_ERR(ctx->mrec))
257 old_ctx.attr = (ATTR_RECORD*)(
261 old_ctx.mrec = ctx->mrec;
264 /* Restore the search context to the saved one. */
267 * We drop the reference on the page we took earlier. In the
268 * case that IS_ERR(ctx->mrec) is true this means we might lose
269 * some changes to the mft record that had been made between
270 * the last time it was marked dirty/written out and now. This
271 * at this stage is not a problem as the mapping error is fatal
272 * enough that the mft record cannot be written out anyway and
273 * the caller is very likely to shutdown the whole inode
274 * immediately and mark the volume dirty for chkdsk to pick up
278 put_page(put_this_page);
284 * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
285 * @ni: ntfs inode for which to map (part of) a runlist
286 * @vcn: map runlist part containing this vcn
288 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
290 * Return 0 on success and -errno on error. There is one special error code
291 * which is not an error as such. This is -ENOENT. It means that @vcn is out
292 * of bounds of the runlist.
294 * Locking: - The runlist must be unlocked on entry and is unlocked on return.
295 * - This function takes the runlist lock for writing and may modify
298 int ntfs_map_runlist(ntfs_inode *ni, VCN vcn)
302 down_write(&ni->runlist.lock);
303 /* Make sure someone else didn't do the work while we were sleeping. */
304 if (likely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) <=
306 err = ntfs_map_runlist_nolock(ni, vcn, NULL);
307 up_write(&ni->runlist.lock);
312 * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
313 * @ni: ntfs inode of the attribute whose runlist to search
314 * @vcn: vcn to convert
315 * @write_locked: true if the runlist is locked for writing
317 * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
318 * described by the ntfs inode @ni and return the corresponding logical cluster
321 * If the @vcn is not mapped yet, the attempt is made to map the attribute
322 * extent containing the @vcn and the vcn to lcn conversion is retried.
324 * If @write_locked is true the caller has locked the runlist for writing and
325 * if false for reading.
327 * Since lcns must be >= 0, we use negative return codes with special meaning:
329 * Return code Meaning / Description
330 * ==========================================
331 * LCN_HOLE Hole / not allocated on disk.
332 * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds.
333 * LCN_ENOMEM Not enough memory to map runlist.
334 * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc).
336 * Locking: - The runlist must be locked on entry and is left locked on return.
337 * - If @write_locked is 'false', i.e. the runlist is locked for reading,
338 * the lock may be dropped inside the function so you cannot rely on
339 * the runlist still being the same when this function returns.
341 LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn,
342 const bool write_locked)
346 bool is_retry = false;
349 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
350 ni->mft_no, (unsigned long long)vcn,
351 write_locked ? "write" : "read");
352 BUG_ON(!NInoNonResident(ni));
354 if (!ni->runlist.rl) {
355 read_lock_irqsave(&ni->size_lock, flags);
356 if (!ni->allocated_size) {
357 read_unlock_irqrestore(&ni->size_lock, flags);
360 read_unlock_irqrestore(&ni->size_lock, flags);
363 /* Convert vcn to lcn. If that fails map the runlist and retry once. */
364 lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn);
365 if (likely(lcn >= LCN_HOLE)) {
366 ntfs_debug("Done, lcn 0x%llx.", (long long)lcn);
369 if (lcn != LCN_RL_NOT_MAPPED) {
370 if (lcn != LCN_ENOENT)
372 } else if (!is_retry) {
376 up_read(&ni->runlist.lock);
377 down_write(&ni->runlist.lock);
378 if (unlikely(ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn) !=
379 LCN_RL_NOT_MAPPED)) {
380 up_write(&ni->runlist.lock);
381 down_read(&ni->runlist.lock);
385 err = ntfs_map_runlist_nolock(ni, vcn, NULL);
387 up_write(&ni->runlist.lock);
388 down_read(&ni->runlist.lock);
396 else if (err == -ENOMEM)
401 if (lcn != LCN_ENOENT)
402 ntfs_error(ni->vol->sb, "Failed with error code %lli.",
408 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
409 * @ni: ntfs inode describing the runlist to search
411 * @ctx: active attribute search context if present or NULL if not
413 * Find the virtual cluster number @vcn in the runlist described by the ntfs
414 * inode @ni and return the address of the runlist element containing the @vcn.
416 * If the @vcn is not mapped yet, the attempt is made to map the attribute
417 * extent containing the @vcn and the vcn to lcn conversion is retried.
419 * If @ctx is specified, it is an active search context of @ni and its base mft
420 * record. This is needed when ntfs_attr_find_vcn_nolock() encounters unmapped
421 * runlist fragments and allows their mapping. If you do not have the mft
422 * record mapped, you can specify @ctx as NULL and ntfs_attr_find_vcn_nolock()
423 * will perform the necessary mapping and unmapping.
425 * Note, ntfs_attr_find_vcn_nolock() saves the state of @ctx on entry and
426 * restores it before returning. Thus, @ctx will be left pointing to the same
427 * attribute on return as on entry. However, the actual pointers in @ctx may
428 * point to different memory locations on return, so you must remember to reset
429 * any cached pointers from the @ctx, i.e. after the call to
430 * ntfs_attr_find_vcn_nolock(), you will probably want to do:
433 * Assuming you cache ctx->attr in a variable @a of type ATTR_RECORD * and that
434 * you cache ctx->mrec in a variable @m of type MFT_RECORD *.
435 * Note you need to distinguish between the lcn of the returned runlist element
436 * being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
437 * read and allocate clusters on write.
439 * Return the runlist element containing the @vcn on success and
440 * ERR_PTR(-errno) on error. You need to test the return value with IS_ERR()
441 * to decide if the return is success or failure and PTR_ERR() to get to the
442 * error code if IS_ERR() is true.
444 * The possible error return codes are:
445 * -ENOENT - No such vcn in the runlist, i.e. @vcn is out of bounds.
446 * -ENOMEM - Not enough memory to map runlist.
447 * -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
449 * WARNING: If @ctx is supplied, regardless of whether success or failure is
450 * returned, you need to check IS_ERR(@ctx->mrec) and if 'true' the @ctx
451 * is no longer valid, i.e. you need to either call
452 * ntfs_attr_reinit_search_ctx() or ntfs_attr_put_search_ctx() on it.
453 * In that case PTR_ERR(@ctx->mrec) will give you the error code for
454 * why the mapping of the old inode failed.
456 * Locking: - The runlist described by @ni must be locked for writing on entry
457 * and is locked on return. Note the runlist may be modified when
458 * needed runlist fragments need to be mapped.
459 * - If @ctx is NULL, the base mft record of @ni must not be mapped on
460 * entry and it will be left unmapped on return.
461 * - If @ctx is not NULL, the base mft record must be mapped on entry
462 * and it will be left mapped on return.
464 runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn,
465 ntfs_attr_search_ctx *ctx)
470 bool is_retry = false;
473 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, with%s ctx.",
474 ni->mft_no, (unsigned long long)vcn, ctx ? "" : "out");
475 BUG_ON(!NInoNonResident(ni));
477 if (!ni->runlist.rl) {
478 read_lock_irqsave(&ni->size_lock, flags);
479 if (!ni->allocated_size) {
480 read_unlock_irqrestore(&ni->size_lock, flags);
481 return ERR_PTR(-ENOENT);
483 read_unlock_irqrestore(&ni->size_lock, flags);
487 if (likely(rl && vcn >= rl[0].vcn)) {
488 while (likely(rl->length)) {
489 if (unlikely(vcn < rl[1].vcn)) {
490 if (likely(rl->lcn >= LCN_HOLE)) {
498 if (likely(rl->lcn != LCN_RL_NOT_MAPPED)) {
499 if (likely(rl->lcn == LCN_ENOENT))
505 if (!err && !is_retry) {
507 * If the search context is invalid we cannot map the unmapped
510 if (IS_ERR(ctx->mrec))
511 err = PTR_ERR(ctx->mrec);
514 * The @vcn is in an unmapped region, map the runlist
517 err = ntfs_map_runlist_nolock(ni, vcn, ctx);
528 ntfs_error(ni->vol->sb, "Failed with error code %i.", err);
533 * ntfs_attr_find - find (next) attribute in mft record
534 * @type: attribute type to find
535 * @name: attribute name to find (optional, i.e. NULL means don't care)
536 * @name_len: attribute name length (only needed if @name present)
537 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
538 * @val: attribute value to find (optional, resident attributes only)
539 * @val_len: attribute value length
540 * @ctx: search context with mft record and attribute to search from
542 * You should not need to call this function directly. Use ntfs_attr_lookup()
545 * ntfs_attr_find() takes a search context @ctx as parameter and searches the
546 * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an
547 * attribute of @type, optionally @name and @val.
549 * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will
550 * point to the found attribute.
552 * If the attribute is not found, ntfs_attr_find() returns -ENOENT and
553 * @ctx->attr will point to the attribute before which the attribute being
554 * searched for would need to be inserted if such an action were to be desired.
556 * On actual error, ntfs_attr_find() returns -EIO. In this case @ctx->attr is
557 * undefined and in particular do not rely on it not changing.
559 * If @ctx->is_first is 'true', the search begins with @ctx->attr itself. If it
560 * is 'false', the search begins after @ctx->attr.
562 * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
563 * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
564 * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at
565 * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case
566 * sensitive. When @name is present, @name_len is the @name length in Unicode
569 * If @name is not present (NULL), we assume that the unnamed attribute is
570 * being searched for.
572 * Finally, the resident attribute value @val is looked for, if present. If
573 * @val is not present (NULL), @val_len is ignored.
575 * ntfs_attr_find() only searches the specified mft record and it ignores the
576 * presence of an attribute list attribute (unless it is the one being searched
577 * for, obviously). If you need to take attribute lists into consideration,
578 * use ntfs_attr_lookup() instead (see below). This also means that you cannot
579 * use ntfs_attr_find() to search for extent records of non-resident
580 * attributes, as extents with lowest_vcn != 0 are usually described by the
581 * attribute list attribute only. - Note that it is possible that the first
582 * extent is only in the attribute list while the last extent is in the base
583 * mft record, so do not rely on being able to find the first extent in the
586 * Warning: Never use @val when looking for attribute types which can be
587 * non-resident as this most likely will result in a crash!
589 static int ntfs_attr_find(const ATTR_TYPE type, const ntfschar *name,
590 const u32 name_len, const IGNORE_CASE_BOOL ic,
591 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
594 ntfs_volume *vol = ctx->ntfs_ino->vol;
595 ntfschar *upcase = vol->upcase;
596 u32 upcase_len = vol->upcase_len;
599 * Iterate over attributes in mft record starting at @ctx->attr, or the
600 * attribute following that, if @ctx->is_first is 'true'.
604 ctx->is_first = false;
606 a = (ATTR_RECORD*)((u8*)ctx->attr +
607 le32_to_cpu(ctx->attr->length));
608 for (;; a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length))) {
609 u8 *mrec_end = (u8 *)ctx->mrec +
610 le32_to_cpu(ctx->mrec->bytes_allocated);
613 /* check whether ATTR_RECORD wrap */
614 if ((u8 *)a < (u8 *)ctx->mrec)
617 /* check whether Attribute Record Header is within bounds */
618 if ((u8 *)a > mrec_end ||
619 (u8 *)a + sizeof(ATTR_RECORD) > mrec_end)
622 /* check whether ATTR_RECORD's name is within bounds */
623 name_end = (u8 *)a + le16_to_cpu(a->name_offset) +
624 a->name_length * sizeof(ntfschar);
625 if (name_end > mrec_end)
629 if (unlikely(le32_to_cpu(a->type) > le32_to_cpu(type) ||
632 if (unlikely(!a->length))
635 /* check whether ATTR_RECORD's length wrap */
636 if ((u8 *)a + le32_to_cpu(a->length) < (u8 *)a)
638 /* check whether ATTR_RECORD's length is within bounds */
639 if ((u8 *)a + le32_to_cpu(a->length) > mrec_end)
645 * If @name is present, compare the two names. If @name is
646 * missing, assume we want an unnamed attribute.
649 /* The search failed if the found attribute is named. */
652 } else if (!ntfs_are_names_equal(name, name_len,
653 (ntfschar*)((u8*)a + le16_to_cpu(a->name_offset)),
654 a->name_length, ic, upcase, upcase_len)) {
657 rc = ntfs_collate_names(name, name_len,
659 le16_to_cpu(a->name_offset)),
660 a->name_length, 1, IGNORE_CASE,
663 * If @name collates before a->name, there is no
664 * matching attribute.
668 /* If the strings are not equal, continue search. */
671 rc = ntfs_collate_names(name, name_len,
673 le16_to_cpu(a->name_offset)),
674 a->name_length, 1, CASE_SENSITIVE,
682 * The names match or @name not present and attribute is
683 * unnamed. If no @val specified, we have found the attribute
688 /* @val is present; compare values. */
692 rc = memcmp(val, (u8*)a + le16_to_cpu(
693 a->data.resident.value_offset),
694 min_t(u32, val_len, le32_to_cpu(
695 a->data.resident.value_length)));
697 * If @val collates before the current attribute's
698 * value, there is no matching attribute.
704 a->data.resident.value_length);
713 ntfs_error(vol->sb, "Inode is corrupt. Run chkdsk.");
719 * load_attribute_list - load an attribute list into memory
720 * @vol: ntfs volume from which to read
721 * @runlist: runlist of the attribute list
722 * @al_start: destination buffer
723 * @size: size of the destination buffer in bytes
724 * @initialized_size: initialized size of the attribute list
726 * Walk the runlist @runlist and load all clusters from it copying them into
727 * the linear buffer @al. The maximum number of bytes copied to @al is @size
728 * bytes. Note, @size does not need to be a multiple of the cluster size. If
729 * @initialized_size is less than @size, the region in @al between
730 * @initialized_size and @size will be zeroed and not read from disk.
732 * Return 0 on success or -errno on error.
734 int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start,
735 const s64 size, const s64 initialized_size)
739 u8 *al_end = al + initialized_size;
741 struct buffer_head *bh;
742 struct super_block *sb;
743 unsigned long block_size;
744 unsigned long block, max_block;
746 unsigned char block_size_bits;
748 ntfs_debug("Entering.");
749 if (!vol || !runlist || !al || size <= 0 || initialized_size < 0 ||
750 initialized_size > size)
752 if (!initialized_size) {
757 block_size = sb->s_blocksize;
758 block_size_bits = sb->s_blocksize_bits;
759 down_read(&runlist->lock);
762 ntfs_error(sb, "Cannot read attribute list since runlist is "
766 /* Read all clusters specified by the runlist one run at a time. */
768 lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn);
769 ntfs_debug("Reading vcn = 0x%llx, lcn = 0x%llx.",
770 (unsigned long long)rl->vcn,
771 (unsigned long long)lcn);
772 /* The attribute list cannot be sparse. */
774 ntfs_error(sb, "ntfs_rl_vcn_to_lcn() failed. Cannot "
775 "read attribute list.");
778 block = lcn << vol->cluster_size_bits >> block_size_bits;
779 /* Read the run from device in chunks of block_size bytes. */
780 max_block = block + (rl->length << vol->cluster_size_bits >>
782 ntfs_debug("max_block = 0x%lx.", max_block);
784 ntfs_debug("Reading block = 0x%lx.", block);
785 bh = sb_bread(sb, block);
787 ntfs_error(sb, "sb_bread() failed. Cannot "
788 "read attribute list.");
791 if (al + block_size >= al_end)
793 memcpy(al, bh->b_data, block_size);
796 } while (++block < max_block);
799 if (initialized_size < size) {
801 memset(al_start + initialized_size, 0, size - initialized_size);
804 up_read(&runlist->lock);
811 * Note: The attribute list can be smaller than its allocation
812 * by multiple clusters. This has been encountered by at least
813 * two people running Windows XP, thus we cannot do any
814 * truncation sanity checking here. (AIA)
816 memcpy(al, bh->b_data, al_end - al);
818 if (initialized_size < size)
824 ntfs_error(sb, "Attribute list buffer overflow. Read attribute list "
832 * ntfs_external_attr_find - find an attribute in the attribute list of an inode
833 * @type: attribute type to find
834 * @name: attribute name to find (optional, i.e. NULL means don't care)
835 * @name_len: attribute name length (only needed if @name present)
836 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
837 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
838 * @val: attribute value to find (optional, resident attributes only)
839 * @val_len: attribute value length
840 * @ctx: search context with mft record and attribute to search from
842 * You should not need to call this function directly. Use ntfs_attr_lookup()
845 * Find an attribute by searching the attribute list for the corresponding
846 * attribute list entry. Having found the entry, map the mft record if the
847 * attribute is in a different mft record/inode, ntfs_attr_find() the attribute
848 * in there and return it.
850 * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
851 * have been obtained from a call to ntfs_attr_get_search_ctx(). On subsequent
852 * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is
853 * then the base inode).
855 * After finishing with the attribute/mft record you need to call
856 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
857 * mapped inodes, etc).
859 * If the attribute is found, ntfs_external_attr_find() returns 0 and
860 * @ctx->attr will point to the found attribute. @ctx->mrec will point to the
861 * mft record in which @ctx->attr is located and @ctx->al_entry will point to
862 * the attribute list entry for the attribute.
864 * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and
865 * @ctx->attr will point to the attribute in the base mft record before which
866 * the attribute being searched for would need to be inserted if such an action
867 * were to be desired. @ctx->mrec will point to the mft record in which
868 * @ctx->attr is located and @ctx->al_entry will point to the attribute list
869 * entry of the attribute before which the attribute being searched for would
870 * need to be inserted if such an action were to be desired.
872 * Thus to insert the not found attribute, one wants to add the attribute to
873 * @ctx->mrec (the base mft record) and if there is not enough space, the
874 * attribute should be placed in a newly allocated extent mft record. The
875 * attribute list entry for the inserted attribute should be inserted in the
876 * attribute list attribute at @ctx->al_entry.
878 * On actual error, ntfs_external_attr_find() returns -EIO. In this case
879 * @ctx->attr is undefined and in particular do not rely on it not changing.
881 static int ntfs_external_attr_find(const ATTR_TYPE type,
882 const ntfschar *name, const u32 name_len,
883 const IGNORE_CASE_BOOL ic, const VCN lowest_vcn,
884 const u8 *val, const u32 val_len, ntfs_attr_search_ctx *ctx)
886 ntfs_inode *base_ni, *ni;
888 ATTR_LIST_ENTRY *al_entry, *next_al_entry;
889 u8 *al_start, *al_end;
894 static const char *es = " Unmount and run chkdsk.";
897 base_ni = ctx->base_ntfs_ino;
898 ntfs_debug("Entering for inode 0x%lx, type 0x%x.", ni->mft_no, type);
900 /* First call happens with the base mft record. */
901 base_ni = ctx->base_ntfs_ino = ctx->ntfs_ino;
902 ctx->base_mrec = ctx->mrec;
905 ctx->base_attr = ctx->attr;
909 al_start = base_ni->attr_list;
910 al_end = al_start + base_ni->attr_list_size;
912 ctx->al_entry = (ATTR_LIST_ENTRY*)al_start;
914 * Iterate over entries in attribute list starting at @ctx->al_entry,
915 * or the entry following that, if @ctx->is_first is 'true'.
918 al_entry = ctx->al_entry;
919 ctx->is_first = false;
921 al_entry = (ATTR_LIST_ENTRY*)((u8*)ctx->al_entry +
922 le16_to_cpu(ctx->al_entry->length));
923 for (;; al_entry = next_al_entry) {
924 /* Out of bounds check. */
925 if ((u8*)al_entry < base_ni->attr_list ||
926 (u8*)al_entry > al_end)
927 break; /* Inode is corrupt. */
928 ctx->al_entry = al_entry;
929 /* Catch the end of the attribute list. */
930 if ((u8*)al_entry == al_end)
932 if (!al_entry->length)
934 if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
935 le16_to_cpu(al_entry->length) > al_end)
937 next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
938 le16_to_cpu(al_entry->length));
939 if (le32_to_cpu(al_entry->type) > le32_to_cpu(type))
941 if (type != al_entry->type)
944 * If @name is present, compare the two names. If @name is
945 * missing, assume we want an unnamed attribute.
947 al_name_len = al_entry->name_length;
948 al_name = (ntfschar*)((u8*)al_entry + al_entry->name_offset);
952 } else if (!ntfs_are_names_equal(al_name, al_name_len, name,
953 name_len, ic, vol->upcase, vol->upcase_len)) {
956 rc = ntfs_collate_names(name, name_len, al_name,
957 al_name_len, 1, IGNORE_CASE,
958 vol->upcase, vol->upcase_len);
960 * If @name collates before al_name, there is no
961 * matching attribute.
965 /* If the strings are not equal, continue search. */
969 * FIXME: Reverse engineering showed 0, IGNORE_CASE but
970 * that is inconsistent with ntfs_attr_find(). The
971 * subsequent rc checks were also different. Perhaps I
972 * made a mistake in one of the two. Need to recheck
973 * which is correct or at least see what is going on...
976 rc = ntfs_collate_names(name, name_len, al_name,
977 al_name_len, 1, CASE_SENSITIVE,
978 vol->upcase, vol->upcase_len);
985 * The names match or @name not present and attribute is
986 * unnamed. Now check @lowest_vcn. Continue search if the
987 * next attribute list entry still fits @lowest_vcn. Otherwise
988 * we have reached the right one or the search has failed.
990 if (lowest_vcn && (u8*)next_al_entry >= al_start &&
991 (u8*)next_al_entry + 6 < al_end &&
992 (u8*)next_al_entry + le16_to_cpu(
993 next_al_entry->length) <= al_end &&
994 sle64_to_cpu(next_al_entry->lowest_vcn) <=
996 next_al_entry->type == al_entry->type &&
997 next_al_entry->name_length == al_name_len &&
998 ntfs_are_names_equal((ntfschar*)((u8*)
1000 next_al_entry->name_offset),
1001 next_al_entry->name_length,
1002 al_name, al_name_len, CASE_SENSITIVE,
1003 vol->upcase, vol->upcase_len))
1005 if (MREF_LE(al_entry->mft_reference) == ni->mft_no) {
1006 if (MSEQNO_LE(al_entry->mft_reference) != ni->seq_no) {
1007 ntfs_error(vol->sb, "Found stale mft "
1008 "reference in attribute list "
1009 "of base inode 0x%lx.%s",
1010 base_ni->mft_no, es);
1014 } else { /* Mft references do not match. */
1015 /* If there is a mapped record unmap it first. */
1017 unmap_extent_mft_record(ni);
1018 /* Do we want the base record back? */
1019 if (MREF_LE(al_entry->mft_reference) ==
1021 ni = ctx->ntfs_ino = base_ni;
1022 ctx->mrec = ctx->base_mrec;
1024 /* We want an extent record. */
1025 ctx->mrec = map_extent_mft_record(base_ni,
1027 al_entry->mft_reference), &ni);
1028 if (IS_ERR(ctx->mrec)) {
1029 ntfs_error(vol->sb, "Failed to map "
1030 "extent mft record "
1031 "0x%lx of base inode "
1035 base_ni->mft_no, es);
1036 err = PTR_ERR(ctx->mrec);
1039 /* Cause @ctx to be sanitized below. */
1045 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
1046 le16_to_cpu(ctx->mrec->attrs_offset));
1049 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
1050 * mft record containing the attribute represented by the
1054 * We could call into ntfs_attr_find() to find the right
1055 * attribute in this mft record but this would be less
1056 * efficient and not quite accurate as ntfs_attr_find() ignores
1057 * the attribute instance numbers for example which become
1058 * important when one plays with attribute lists. Also,
1059 * because a proper match has been found in the attribute list
1060 * entry above, the comparison can now be optimized. So it is
1061 * worth re-implementing a simplified ntfs_attr_find() here.
1065 * Use a manual loop so we can still use break and continue
1066 * with the same meanings as above.
1069 if ((u8*)a < (u8*)ctx->mrec || (u8*)a > (u8*)ctx->mrec +
1070 le32_to_cpu(ctx->mrec->bytes_allocated))
1072 if (a->type == AT_END)
1076 if (al_entry->instance != a->instance)
1079 * If the type and/or the name are mismatched between the
1080 * attribute list entry and the attribute record, there is
1081 * corruption so we break and return error EIO.
1083 if (al_entry->type != a->type)
1085 if (!ntfs_are_names_equal((ntfschar*)((u8*)a +
1086 le16_to_cpu(a->name_offset)), a->name_length,
1087 al_name, al_name_len, CASE_SENSITIVE,
1088 vol->upcase, vol->upcase_len))
1092 * If no @val specified or @val specified and it matches, we
1095 if (!val || (!a->non_resident && le32_to_cpu(
1096 a->data.resident.value_length) == val_len &&
1098 le16_to_cpu(a->data.resident.value_offset),
1100 ntfs_debug("Done, found.");
1104 /* Proceed to the next attribute in the current mft record. */
1105 a = (ATTR_RECORD*)((u8*)a + le32_to_cpu(a->length));
1106 goto do_next_attr_loop;
1109 ntfs_error(vol->sb, "Base inode 0x%lx contains corrupt "
1110 "attribute list attribute.%s", base_ni->mft_no,
1114 if (ni != base_ni) {
1116 unmap_extent_mft_record(ni);
1117 ctx->ntfs_ino = base_ni;
1118 ctx->mrec = ctx->base_mrec;
1119 ctx->attr = ctx->base_attr;
1126 * If we were looking for AT_END, we reset the search context @ctx and
1127 * use ntfs_attr_find() to seek to the end of the base mft record.
1129 if (type == AT_END) {
1130 ntfs_attr_reinit_search_ctx(ctx);
1131 return ntfs_attr_find(AT_END, name, name_len, ic, val, val_len,
1135 * The attribute was not found. Before we return, we want to ensure
1136 * @ctx->mrec and @ctx->attr indicate the position at which the
1137 * attribute should be inserted in the base mft record. Since we also
1138 * want to preserve @ctx->al_entry we cannot reinitialize the search
1139 * context using ntfs_attr_reinit_search_ctx() as this would set
1140 * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see
1141 * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve
1142 * @ctx->al_entry as the remaining fields (base_*) are identical to
1143 * their non base_ counterparts and we cannot set @ctx->base_attr
1144 * correctly yet as we do not know what @ctx->attr will be set to by
1145 * the call to ntfs_attr_find() below.
1148 unmap_extent_mft_record(ni);
1149 ctx->mrec = ctx->base_mrec;
1150 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
1151 le16_to_cpu(ctx->mrec->attrs_offset));
1152 ctx->is_first = true;
1153 ctx->ntfs_ino = base_ni;
1154 ctx->base_ntfs_ino = NULL;
1155 ctx->base_mrec = NULL;
1156 ctx->base_attr = NULL;
1158 * In case there are multiple matches in the base mft record, need to
1159 * keep enumerating until we get an attribute not found response (or
1160 * another error), otherwise we would keep returning the same attribute
1161 * over and over again and all programs using us for enumeration would
1162 * lock up in a tight loop.
1165 err = ntfs_attr_find(type, name, name_len, ic, val, val_len,
1168 ntfs_debug("Done, not found.");
1173 * ntfs_attr_lookup - find an attribute in an ntfs inode
1174 * @type: attribute type to find
1175 * @name: attribute name to find (optional, i.e. NULL means don't care)
1176 * @name_len: attribute name length (only needed if @name present)
1177 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
1178 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
1179 * @val: attribute value to find (optional, resident attributes only)
1180 * @val_len: attribute value length
1181 * @ctx: search context with mft record and attribute to search from
1183 * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must
1184 * be the base mft record and @ctx must have been obtained from a call to
1185 * ntfs_attr_get_search_ctx().
1187 * This function transparently handles attribute lists and @ctx is used to
1188 * continue searches where they were left off at.
1190 * After finishing with the attribute/mft record you need to call
1191 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
1192 * mapped inodes, etc).
1194 * Return 0 if the search was successful and -errno if not.
1196 * When 0, @ctx->attr is the found attribute and it is in mft record
1197 * @ctx->mrec. If an attribute list attribute is present, @ctx->al_entry is
1198 * the attribute list entry of the found attribute.
1200 * When -ENOENT, @ctx->attr is the attribute which collates just after the
1201 * attribute being searched for, i.e. if one wants to add the attribute to the
1202 * mft record this is the correct place to insert it into. If an attribute
1203 * list attribute is present, @ctx->al_entry is the attribute list entry which
1204 * collates just after the attribute list entry of the attribute being searched
1205 * for, i.e. if one wants to add the attribute to the mft record this is the
1206 * correct place to insert its attribute list entry into.
1208 * When -errno != -ENOENT, an error occurred during the lookup. @ctx->attr is
1209 * then undefined and in particular you should not rely on it not changing.
1211 int ntfs_attr_lookup(const ATTR_TYPE type, const ntfschar *name,
1212 const u32 name_len, const IGNORE_CASE_BOOL ic,
1213 const VCN lowest_vcn, const u8 *val, const u32 val_len,
1214 ntfs_attr_search_ctx *ctx)
1216 ntfs_inode *base_ni;
1218 ntfs_debug("Entering.");
1219 BUG_ON(IS_ERR(ctx->mrec));
1220 if (ctx->base_ntfs_ino)
1221 base_ni = ctx->base_ntfs_ino;
1223 base_ni = ctx->ntfs_ino;
1224 /* Sanity check, just for debugging really. */
1226 if (!NInoAttrList(base_ni) || type == AT_ATTRIBUTE_LIST)
1227 return ntfs_attr_find(type, name, name_len, ic, val, val_len,
1229 return ntfs_external_attr_find(type, name, name_len, ic, lowest_vcn,
1234 * ntfs_attr_init_search_ctx - initialize an attribute search context
1235 * @ctx: attribute search context to initialize
1236 * @ni: ntfs inode with which to initialize the search context
1237 * @mrec: mft record with which to initialize the search context
1239 * Initialize the attribute search context @ctx with @ni and @mrec.
1241 static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx *ctx,
1242 ntfs_inode *ni, MFT_RECORD *mrec)
1244 *ctx = (ntfs_attr_search_ctx) {
1246 /* Sanity checks are performed elsewhere. */
1247 .attr = (ATTR_RECORD*)((u8*)mrec +
1248 le16_to_cpu(mrec->attrs_offset)),
1255 * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context
1256 * @ctx: attribute search context to reinitialize
1258 * Reinitialize the attribute search context @ctx, unmapping an associated
1259 * extent mft record if present, and initialize the search context again.
1261 * This is used when a search for a new attribute is being started to reset
1262 * the search context to the beginning.
1264 void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx *ctx)
1266 if (likely(!ctx->base_ntfs_ino)) {
1267 /* No attribute list. */
1268 ctx->is_first = true;
1269 /* Sanity checks are performed elsewhere. */
1270 ctx->attr = (ATTR_RECORD*)((u8*)ctx->mrec +
1271 le16_to_cpu(ctx->mrec->attrs_offset));
1273 * This needs resetting due to ntfs_external_attr_find() which
1274 * can leave it set despite having zeroed ctx->base_ntfs_ino.
1276 ctx->al_entry = NULL;
1278 } /* Attribute list. */
1279 if (ctx->ntfs_ino != ctx->base_ntfs_ino)
1280 unmap_extent_mft_record(ctx->ntfs_ino);
1281 ntfs_attr_init_search_ctx(ctx, ctx->base_ntfs_ino, ctx->base_mrec);
1286 * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context
1287 * @ni: ntfs inode with which to initialize the search context
1288 * @mrec: mft record with which to initialize the search context
1290 * Allocate a new attribute search context, initialize it with @ni and @mrec,
1291 * and return it. Return NULL if allocation failed.
1293 ntfs_attr_search_ctx *ntfs_attr_get_search_ctx(ntfs_inode *ni, MFT_RECORD *mrec)
1295 ntfs_attr_search_ctx *ctx;
1297 ctx = kmem_cache_alloc(ntfs_attr_ctx_cache, GFP_NOFS);
1299 ntfs_attr_init_search_ctx(ctx, ni, mrec);
1304 * ntfs_attr_put_search_ctx - release an attribute search context
1305 * @ctx: attribute search context to free
1307 * Release the attribute search context @ctx, unmapping an associated extent
1308 * mft record if present.
1310 void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx *ctx)
1312 if (ctx->base_ntfs_ino && ctx->ntfs_ino != ctx->base_ntfs_ino)
1313 unmap_extent_mft_record(ctx->ntfs_ino);
1314 kmem_cache_free(ntfs_attr_ctx_cache, ctx);
1321 * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
1322 * @vol: ntfs volume to which the attribute belongs
1323 * @type: attribute type which to find
1325 * Search for the attribute definition record corresponding to the attribute
1326 * @type in the $AttrDef system file.
1328 * Return the attribute type definition record if found and NULL if not found.
1330 static ATTR_DEF *ntfs_attr_find_in_attrdef(const ntfs_volume *vol,
1331 const ATTR_TYPE type)
1335 BUG_ON(!vol->attrdef);
1337 for (ad = vol->attrdef; (u8*)ad - (u8*)vol->attrdef <
1338 vol->attrdef_size && ad->type; ++ad) {
1339 /* We have not found it yet, carry on searching. */
1340 if (likely(le32_to_cpu(ad->type) < le32_to_cpu(type)))
1342 /* We found the attribute; return it. */
1343 if (likely(ad->type == type))
1345 /* We have gone too far already. No point in continuing. */
1348 /* Attribute not found. */
1349 ntfs_debug("Attribute type 0x%x not found in $AttrDef.",
1355 * ntfs_attr_size_bounds_check - check a size of an attribute type for validity
1356 * @vol: ntfs volume to which the attribute belongs
1357 * @type: attribute type which to check
1358 * @size: size which to check
1360 * Check whether the @size in bytes is valid for an attribute of @type on the
1361 * ntfs volume @vol. This information is obtained from $AttrDef system file.
1363 * Return 0 if valid, -ERANGE if not valid, or -ENOENT if the attribute is not
1364 * listed in $AttrDef.
1366 int ntfs_attr_size_bounds_check(const ntfs_volume *vol, const ATTR_TYPE type,
1373 * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not
1374 * listed in $AttrDef.
1376 if (unlikely(type == AT_ATTRIBUTE_LIST && size > 256 * 1024))
1378 /* Get the $AttrDef entry for the attribute @type. */
1379 ad = ntfs_attr_find_in_attrdef(vol, type);
1382 /* Do the bounds check. */
1383 if (((sle64_to_cpu(ad->min_size) > 0) &&
1384 size < sle64_to_cpu(ad->min_size)) ||
1385 ((sle64_to_cpu(ad->max_size) > 0) && size >
1386 sle64_to_cpu(ad->max_size)))
1392 * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident
1393 * @vol: ntfs volume to which the attribute belongs
1394 * @type: attribute type which to check
1396 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1397 * be non-resident. This information is obtained from $AttrDef system file.
1399 * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, and
1400 * -ENOENT if the attribute is not listed in $AttrDef.
1402 int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1406 /* Find the attribute definition record in $AttrDef. */
1407 ad = ntfs_attr_find_in_attrdef(vol, type);
1410 /* Check the flags and return the result. */
1411 if (ad->flags & ATTR_DEF_RESIDENT)
1417 * ntfs_attr_can_be_resident - check if an attribute can be resident
1418 * @vol: ntfs volume to which the attribute belongs
1419 * @type: attribute type which to check
1421 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1422 * be resident. This information is derived from our ntfs knowledge and may
1423 * not be completely accurate, especially when user defined attributes are
1424 * present. Basically we allow everything to be resident except for index
1425 * allocation and $EA attributes.
1427 * Return 0 if the attribute is allowed to be non-resident and -EPERM if not.
1429 * Warning: In the system file $MFT the attribute $Bitmap must be non-resident
1430 * otherwise windows will not boot (blue screen of death)! We cannot
1431 * check for this here as we do not know which inode's $Bitmap is
1432 * being asked about so the caller needs to special case this.
1434 int ntfs_attr_can_be_resident(const ntfs_volume *vol, const ATTR_TYPE type)
1436 if (type == AT_INDEX_ALLOCATION)
1442 * ntfs_attr_record_resize - resize an attribute record
1443 * @m: mft record containing attribute record
1444 * @a: attribute record to resize
1445 * @new_size: new size in bytes to which to resize the attribute record @a
1447 * Resize the attribute record @a, i.e. the resident part of the attribute, in
1448 * the mft record @m to @new_size bytes.
1450 * Return 0 on success and -errno on error. The following error codes are
1452 * -ENOSPC - Not enough space in the mft record @m to perform the resize.
1454 * Note: On error, no modifications have been performed whatsoever.
1456 * Warning: If you make a record smaller without having copied all the data you
1457 * are interested in the data may be overwritten.
1459 int ntfs_attr_record_resize(MFT_RECORD *m, ATTR_RECORD *a, u32 new_size)
1461 ntfs_debug("Entering for new_size %u.", new_size);
1462 /* Align to 8 bytes if it is not already done. */
1464 new_size = (new_size + 7) & ~7;
1465 /* If the actual attribute length has changed, move things around. */
1466 if (new_size != le32_to_cpu(a->length)) {
1467 u32 new_muse = le32_to_cpu(m->bytes_in_use) -
1468 le32_to_cpu(a->length) + new_size;
1469 /* Not enough space in this mft record. */
1470 if (new_muse > le32_to_cpu(m->bytes_allocated))
1472 /* Move attributes following @a to their new location. */
1473 memmove((u8*)a + new_size, (u8*)a + le32_to_cpu(a->length),
1474 le32_to_cpu(m->bytes_in_use) - ((u8*)a -
1475 (u8*)m) - le32_to_cpu(a->length));
1476 /* Adjust @m to reflect the change in used space. */
1477 m->bytes_in_use = cpu_to_le32(new_muse);
1478 /* Adjust @a to reflect the new size. */
1479 if (new_size >= offsetof(ATTR_REC, length) + sizeof(a->length))
1480 a->length = cpu_to_le32(new_size);
1486 * ntfs_resident_attr_value_resize - resize the value of a resident attribute
1487 * @m: mft record containing attribute record
1488 * @a: attribute record whose value to resize
1489 * @new_size: new size in bytes to which to resize the attribute value of @a
1491 * Resize the value of the attribute @a in the mft record @m to @new_size bytes.
1492 * If the value is made bigger, the newly allocated space is cleared.
1494 * Return 0 on success and -errno on error. The following error codes are
1496 * -ENOSPC - Not enough space in the mft record @m to perform the resize.
1498 * Note: On error, no modifications have been performed whatsoever.
1500 * Warning: If you make a record smaller without having copied all the data you
1501 * are interested in the data may be overwritten.
1503 int ntfs_resident_attr_value_resize(MFT_RECORD *m, ATTR_RECORD *a,
1508 /* Resize the resident part of the attribute record. */
1509 if (ntfs_attr_record_resize(m, a,
1510 le16_to_cpu(a->data.resident.value_offset) + new_size))
1513 * The resize succeeded! If we made the attribute value bigger, clear
1514 * the area between the old size and @new_size.
1516 old_size = le32_to_cpu(a->data.resident.value_length);
1517 if (new_size > old_size)
1518 memset((u8*)a + le16_to_cpu(a->data.resident.value_offset) +
1519 old_size, 0, new_size - old_size);
1520 /* Finally update the length of the attribute value. */
1521 a->data.resident.value_length = cpu_to_le32(new_size);
1526 * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
1527 * @ni: ntfs inode describing the attribute to convert
1528 * @data_size: size of the resident data to copy to the non-resident attribute
1530 * Convert the resident ntfs attribute described by the ntfs inode @ni to a
1533 * @data_size must be equal to the attribute value size. This is needed since
1534 * we need to know the size before we can map the mft record and our callers
1535 * always know it. The reason we cannot simply read the size from the vfs
1536 * inode i_size is that this is not necessarily uptodate. This happens when
1537 * ntfs_attr_make_non_resident() is called in the ->truncate call path(s).
1539 * Return 0 on success and -errno on error. The following error return codes
1541 * -EPERM - The attribute is not allowed to be non-resident.
1542 * -ENOMEM - Not enough memory.
1543 * -ENOSPC - Not enough disk space.
1544 * -EINVAL - Attribute not defined on the volume.
1545 * -EIO - I/o error or other error.
1546 * Note that -ENOSPC is also returned in the case that there is not enough
1547 * space in the mft record to do the conversion. This can happen when the mft
1548 * record is already very full. The caller is responsible for trying to make
1549 * space in the mft record and trying again. FIXME: Do we need a separate
1550 * error return code for this kind of -ENOSPC or is it always worth trying
1551 * again in case the attribute may then fit in a resident state so no need to
1552 * make it non-resident at all? Ho-hum... (AIA)
1554 * NOTE to self: No changes in the attribute list are required to move from
1555 * a resident to a non-resident attribute.
1557 * Locking: - The caller must hold i_mutex on the inode.
1559 int ntfs_attr_make_non_resident(ntfs_inode *ni, const u32 data_size)
1562 struct inode *vi = VFS_I(ni);
1563 ntfs_volume *vol = ni->vol;
1564 ntfs_inode *base_ni;
1567 ntfs_attr_search_ctx *ctx;
1569 runlist_element *rl;
1571 unsigned long flags;
1572 int mp_size, mp_ofs, name_ofs, arec_size, err, err2;
1574 u8 old_res_attr_flags;
1576 /* Check that the attribute is allowed to be non-resident. */
1577 err = ntfs_attr_can_be_non_resident(vol, ni->type);
1578 if (unlikely(err)) {
1580 ntfs_debug("Attribute is not allowed to be "
1583 ntfs_debug("Attribute not defined on the NTFS "
1588 * FIXME: Compressed and encrypted attributes are not supported when
1589 * writing and we should never have gotten here for them.
1591 BUG_ON(NInoCompressed(ni));
1592 BUG_ON(NInoEncrypted(ni));
1594 * The size needs to be aligned to a cluster boundary for allocation
1597 new_size = (data_size + vol->cluster_size - 1) &
1598 ~(vol->cluster_size - 1);
1601 * Will need the page later and since the page lock nests
1602 * outside all ntfs locks, we need to get the page now.
1604 page = find_or_create_page(vi->i_mapping, 0,
1605 mapping_gfp_mask(vi->i_mapping));
1606 if (unlikely(!page))
1608 /* Start by allocating clusters to hold the attribute value. */
1609 rl = ntfs_cluster_alloc(vol, 0, new_size >>
1610 vol->cluster_size_bits, -1, DATA_ZONE, true);
1613 ntfs_debug("Failed to allocate cluster%s, error code "
1615 vol->cluster_size_bits) > 1 ? "s" : "",
1623 /* Determine the size of the mapping pairs array. */
1624 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl, 0, -1);
1625 if (unlikely(mp_size < 0)) {
1627 ntfs_debug("Failed to get size for mapping pairs array, error "
1631 down_write(&ni->runlist.lock);
1635 base_ni = ni->ext.base_ntfs_ino;
1636 m = map_mft_record(base_ni);
1643 ctx = ntfs_attr_get_search_ctx(base_ni, m);
1644 if (unlikely(!ctx)) {
1648 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1649 CASE_SENSITIVE, 0, NULL, 0, ctx);
1650 if (unlikely(err)) {
1657 BUG_ON(NInoNonResident(ni));
1658 BUG_ON(a->non_resident);
1660 * Calculate new offsets for the name and the mapping pairs array.
1662 if (NInoSparse(ni) || NInoCompressed(ni))
1663 name_ofs = (offsetof(ATTR_REC,
1664 data.non_resident.compressed_size) +
1665 sizeof(a->data.non_resident.compressed_size) +
1668 name_ofs = (offsetof(ATTR_REC,
1669 data.non_resident.compressed_size) + 7) & ~7;
1670 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1672 * Determine the size of the resident part of the now non-resident
1675 arec_size = (mp_ofs + mp_size + 7) & ~7;
1677 * If the page is not uptodate bring it uptodate by copying from the
1680 attr_size = le32_to_cpu(a->data.resident.value_length);
1681 BUG_ON(attr_size != data_size);
1682 if (page && !PageUptodate(page)) {
1683 kaddr = kmap_atomic(page);
1684 memcpy(kaddr, (u8*)a +
1685 le16_to_cpu(a->data.resident.value_offset),
1687 memset(kaddr + attr_size, 0, PAGE_SIZE - attr_size);
1688 kunmap_atomic(kaddr);
1689 flush_dcache_page(page);
1690 SetPageUptodate(page);
1692 /* Backup the attribute flag. */
1693 old_res_attr_flags = a->data.resident.flags;
1694 /* Resize the resident part of the attribute record. */
1695 err = ntfs_attr_record_resize(m, a, arec_size);
1699 * Convert the resident part of the attribute record to describe a
1700 * non-resident attribute.
1702 a->non_resident = 1;
1703 /* Move the attribute name if it exists and update the offset. */
1705 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1706 a->name_length * sizeof(ntfschar));
1707 a->name_offset = cpu_to_le16(name_ofs);
1708 /* Setup the fields specific to non-resident attributes. */
1709 a->data.non_resident.lowest_vcn = 0;
1710 a->data.non_resident.highest_vcn = cpu_to_sle64((new_size - 1) >>
1711 vol->cluster_size_bits);
1712 a->data.non_resident.mapping_pairs_offset = cpu_to_le16(mp_ofs);
1713 memset(&a->data.non_resident.reserved, 0,
1714 sizeof(a->data.non_resident.reserved));
1715 a->data.non_resident.allocated_size = cpu_to_sle64(new_size);
1716 a->data.non_resident.data_size =
1717 a->data.non_resident.initialized_size =
1718 cpu_to_sle64(attr_size);
1719 if (NInoSparse(ni) || NInoCompressed(ni)) {
1720 a->data.non_resident.compression_unit = 0;
1721 if (NInoCompressed(ni) || vol->major_ver < 3)
1722 a->data.non_resident.compression_unit = 4;
1723 a->data.non_resident.compressed_size =
1724 a->data.non_resident.allocated_size;
1726 a->data.non_resident.compression_unit = 0;
1727 /* Generate the mapping pairs array into the attribute record. */
1728 err = ntfs_mapping_pairs_build(vol, (u8*)a + mp_ofs,
1729 arec_size - mp_ofs, rl, 0, -1, NULL);
1730 if (unlikely(err)) {
1731 ntfs_debug("Failed to build mapping pairs, error code %i.",
1735 /* Setup the in-memory attribute structure to be non-resident. */
1736 ni->runlist.rl = rl;
1737 write_lock_irqsave(&ni->size_lock, flags);
1738 ni->allocated_size = new_size;
1739 if (NInoSparse(ni) || NInoCompressed(ni)) {
1740 ni->itype.compressed.size = ni->allocated_size;
1741 if (a->data.non_resident.compression_unit) {
1742 ni->itype.compressed.block_size = 1U << (a->data.
1743 non_resident.compression_unit +
1744 vol->cluster_size_bits);
1745 ni->itype.compressed.block_size_bits =
1746 ffs(ni->itype.compressed.block_size) -
1748 ni->itype.compressed.block_clusters = 1U <<
1749 a->data.non_resident.compression_unit;
1751 ni->itype.compressed.block_size = 0;
1752 ni->itype.compressed.block_size_bits = 0;
1753 ni->itype.compressed.block_clusters = 0;
1755 vi->i_blocks = ni->itype.compressed.size >> 9;
1757 vi->i_blocks = ni->allocated_size >> 9;
1758 write_unlock_irqrestore(&ni->size_lock, flags);
1760 * This needs to be last since the address space operations ->readpage
1761 * and ->writepage can run concurrently with us as they are not
1762 * serialized on i_mutex. Note, we are not allowed to fail once we flip
1763 * this switch, which is another reason to do this last.
1765 NInoSetNonResident(ni);
1766 /* Mark the mft record dirty, so it gets written back. */
1767 flush_dcache_mft_record_page(ctx->ntfs_ino);
1768 mark_mft_record_dirty(ctx->ntfs_ino);
1769 ntfs_attr_put_search_ctx(ctx);
1770 unmap_mft_record(base_ni);
1771 up_write(&ni->runlist.lock);
1773 set_page_dirty(page);
1777 ntfs_debug("Done.");
1780 /* Convert the attribute back into a resident attribute. */
1781 a->non_resident = 0;
1782 /* Move the attribute name if it exists and update the offset. */
1783 name_ofs = (offsetof(ATTR_RECORD, data.resident.reserved) +
1784 sizeof(a->data.resident.reserved) + 7) & ~7;
1786 memmove((u8*)a + name_ofs, (u8*)a + le16_to_cpu(a->name_offset),
1787 a->name_length * sizeof(ntfschar));
1788 mp_ofs = (name_ofs + a->name_length * sizeof(ntfschar) + 7) & ~7;
1789 a->name_offset = cpu_to_le16(name_ofs);
1790 arec_size = (mp_ofs + attr_size + 7) & ~7;
1791 /* Resize the resident part of the attribute record. */
1792 err2 = ntfs_attr_record_resize(m, a, arec_size);
1793 if (unlikely(err2)) {
1795 * This cannot happen (well if memory corruption is at work it
1796 * could happen in theory), but deal with it as well as we can.
1797 * If the old size is too small, truncate the attribute,
1798 * otherwise simply give it a larger allocated size.
1799 * FIXME: Should check whether chkdsk complains when the
1800 * allocated size is much bigger than the resident value size.
1802 arec_size = le32_to_cpu(a->length);
1803 if ((mp_ofs + attr_size) > arec_size) {
1805 attr_size = arec_size - mp_ofs;
1806 ntfs_error(vol->sb, "Failed to undo partial resident "
1807 "to non-resident attribute "
1808 "conversion. Truncating inode 0x%lx, "
1809 "attribute type 0x%x from %i bytes to "
1810 "%i bytes to maintain metadata "
1811 "consistency. THIS MEANS YOU ARE "
1812 "LOSING %i BYTES DATA FROM THIS %s.",
1814 (unsigned)le32_to_cpu(ni->type),
1815 err2, attr_size, err2 - attr_size,
1816 ((ni->type == AT_DATA) &&
1817 !ni->name_len) ? "FILE": "ATTRIBUTE");
1818 write_lock_irqsave(&ni->size_lock, flags);
1819 ni->initialized_size = attr_size;
1820 i_size_write(vi, attr_size);
1821 write_unlock_irqrestore(&ni->size_lock, flags);
1824 /* Setup the fields specific to resident attributes. */
1825 a->data.resident.value_length = cpu_to_le32(attr_size);
1826 a->data.resident.value_offset = cpu_to_le16(mp_ofs);
1827 a->data.resident.flags = old_res_attr_flags;
1828 memset(&a->data.resident.reserved, 0,
1829 sizeof(a->data.resident.reserved));
1830 /* Copy the data from the page back to the attribute value. */
1832 kaddr = kmap_atomic(page);
1833 memcpy((u8*)a + mp_ofs, kaddr, attr_size);
1834 kunmap_atomic(kaddr);
1836 /* Setup the allocated size in the ntfs inode in case it changed. */
1837 write_lock_irqsave(&ni->size_lock, flags);
1838 ni->allocated_size = arec_size - mp_ofs;
1839 write_unlock_irqrestore(&ni->size_lock, flags);
1840 /* Mark the mft record dirty, so it gets written back. */
1841 flush_dcache_mft_record_page(ctx->ntfs_ino);
1842 mark_mft_record_dirty(ctx->ntfs_ino);
1845 ntfs_attr_put_search_ctx(ctx);
1847 unmap_mft_record(base_ni);
1848 ni->runlist.rl = NULL;
1849 up_write(&ni->runlist.lock);
1852 if (ntfs_cluster_free_from_rl(vol, rl) < 0) {
1853 ntfs_error(vol->sb, "Failed to release allocated "
1854 "cluster(s) in error code path. Run "
1855 "chkdsk to recover the lost "
1870 * ntfs_attr_extend_allocation - extend the allocated space of an attribute
1871 * @ni: ntfs inode of the attribute whose allocation to extend
1872 * @new_alloc_size: new size in bytes to which to extend the allocation to
1873 * @new_data_size: new size in bytes to which to extend the data to
1874 * @data_start: beginning of region which is required to be non-sparse
1876 * Extend the allocated space of an attribute described by the ntfs inode @ni
1877 * to @new_alloc_size bytes. If @data_start is -1, the whole extension may be
1878 * implemented as a hole in the file (as long as both the volume and the ntfs
1879 * inode @ni have sparse support enabled). If @data_start is >= 0, then the
1880 * region between the old allocated size and @data_start - 1 may be made sparse
1881 * but the regions between @data_start and @new_alloc_size must be backed by
1884 * If @new_data_size is -1, it is ignored. If it is >= 0, then the data size
1885 * of the attribute is extended to @new_data_size. Note that the i_size of the
1886 * vfs inode is not updated. Only the data size in the base attribute record
1887 * is updated. The caller has to update i_size separately if this is required.
1888 * WARNING: It is a BUG() for @new_data_size to be smaller than the old data
1889 * size as well as for @new_data_size to be greater than @new_alloc_size.
1891 * For resident attributes this involves resizing the attribute record and if
1892 * necessary moving it and/or other attributes into extent mft records and/or
1893 * converting the attribute to a non-resident attribute which in turn involves
1894 * extending the allocation of a non-resident attribute as described below.
1896 * For non-resident attributes this involves allocating clusters in the data
1897 * zone on the volume (except for regions that are being made sparse) and
1898 * extending the run list to describe the allocated clusters as well as
1899 * updating the mapping pairs array of the attribute. This in turn involves
1900 * resizing the attribute record and if necessary moving it and/or other
1901 * attributes into extent mft records and/or splitting the attribute record
1902 * into multiple extent attribute records.
1904 * Also, the attribute list attribute is updated if present and in some of the
1905 * above cases (the ones where extent mft records/attributes come into play),
1906 * an attribute list attribute is created if not already present.
1908 * Return the new allocated size on success and -errno on error. In the case
1909 * that an error is encountered but a partial extension at least up to
1910 * @data_start (if present) is possible, the allocation is partially extended
1911 * and this is returned. This means the caller must check the returned size to
1912 * determine if the extension was partial. If @data_start is -1 then partial
1913 * allocations are not performed.
1915 * WARNING: Do not call ntfs_attr_extend_allocation() for $MFT/$DATA.
1917 * Locking: This function takes the runlist lock of @ni for writing as well as
1918 * locking the mft record of the base ntfs inode. These locks are maintained
1919 * throughout execution of the function. These locks are required so that the
1920 * attribute can be resized safely and so that it can for example be converted
1921 * from resident to non-resident safely.
1923 * TODO: At present attribute list attribute handling is not implemented.
1925 * TODO: At present it is not safe to call this function for anything other
1926 * than the $DATA attribute(s) of an uncompressed and unencrypted file.
1928 s64 ntfs_attr_extend_allocation(ntfs_inode *ni, s64 new_alloc_size,
1929 const s64 new_data_size, const s64 data_start)
1932 s64 ll, allocated_size, start = data_start;
1933 struct inode *vi = VFS_I(ni);
1934 ntfs_volume *vol = ni->vol;
1935 ntfs_inode *base_ni;
1938 ntfs_attr_search_ctx *ctx;
1939 runlist_element *rl, *rl2;
1940 unsigned long flags;
1942 u32 attr_len = 0; /* Silence stupid gcc warning. */
1946 read_lock_irqsave(&ni->size_lock, flags);
1947 allocated_size = ni->allocated_size;
1948 read_unlock_irqrestore(&ni->size_lock, flags);
1949 ntfs_debug("Entering for i_ino 0x%lx, attribute type 0x%x, "
1950 "old_allocated_size 0x%llx, "
1951 "new_allocated_size 0x%llx, new_data_size 0x%llx, "
1952 "data_start 0x%llx.", vi->i_ino,
1953 (unsigned)le32_to_cpu(ni->type),
1954 (unsigned long long)allocated_size,
1955 (unsigned long long)new_alloc_size,
1956 (unsigned long long)new_data_size,
1957 (unsigned long long)start);
1961 * For non-resident attributes, @start and @new_size need to be aligned
1962 * to cluster boundaries for allocation purposes.
1964 if (NInoNonResident(ni)) {
1966 start &= ~(s64)vol->cluster_size_mask;
1967 new_alloc_size = (new_alloc_size + vol->cluster_size - 1) &
1968 ~(s64)vol->cluster_size_mask;
1970 BUG_ON(new_data_size >= 0 && new_data_size > new_alloc_size);
1971 /* Check if new size is allowed in $AttrDef. */
1972 err = ntfs_attr_size_bounds_check(vol, ni->type, new_alloc_size);
1973 if (unlikely(err)) {
1974 /* Only emit errors when the write will fail completely. */
1975 read_lock_irqsave(&ni->size_lock, flags);
1976 allocated_size = ni->allocated_size;
1977 read_unlock_irqrestore(&ni->size_lock, flags);
1978 if (start < 0 || start >= allocated_size) {
1979 if (err == -ERANGE) {
1980 ntfs_error(vol->sb, "Cannot extend allocation "
1981 "of inode 0x%lx, attribute "
1982 "type 0x%x, because the new "
1983 "allocation would exceed the "
1984 "maximum allowed size for "
1985 "this attribute type.",
1986 vi->i_ino, (unsigned)
1987 le32_to_cpu(ni->type));
1989 ntfs_error(vol->sb, "Cannot extend allocation "
1990 "of inode 0x%lx, attribute "
1991 "type 0x%x, because this "
1992 "attribute type is not "
1993 "defined on the NTFS volume. "
1994 "Possible corruption! You "
1995 "should run chkdsk!",
1996 vi->i_ino, (unsigned)
1997 le32_to_cpu(ni->type));
2000 /* Translate error code to be POSIX conformant for write(2). */
2010 base_ni = ni->ext.base_ntfs_ino;
2012 * We will be modifying both the runlist (if non-resident) and the mft
2013 * record so lock them both down.
2015 down_write(&ni->runlist.lock);
2016 m = map_mft_record(base_ni);
2023 ctx = ntfs_attr_get_search_ctx(base_ni, m);
2024 if (unlikely(!ctx)) {
2028 read_lock_irqsave(&ni->size_lock, flags);
2029 allocated_size = ni->allocated_size;
2030 read_unlock_irqrestore(&ni->size_lock, flags);
2032 * If non-resident, seek to the last extent. If resident, there is
2033 * only one extent, so seek to that.
2035 vcn = NInoNonResident(ni) ? allocated_size >> vol->cluster_size_bits :
2038 * Abort if someone did the work whilst we waited for the locks. If we
2039 * just converted the attribute from resident to non-resident it is
2040 * likely that exactly this has happened already. We cannot quite
2041 * abort if we need to update the data size.
2043 if (unlikely(new_alloc_size <= allocated_size)) {
2044 ntfs_debug("Allocated size already exceeds requested size.");
2045 new_alloc_size = allocated_size;
2046 if (new_data_size < 0)
2049 * We want the first attribute extent so that we can update the
2054 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2055 CASE_SENSITIVE, vcn, NULL, 0, ctx);
2056 if (unlikely(err)) {
2063 /* Use goto to reduce indentation. */
2064 if (a->non_resident)
2065 goto do_non_resident_extend;
2066 BUG_ON(NInoNonResident(ni));
2067 /* The total length of the attribute value. */
2068 attr_len = le32_to_cpu(a->data.resident.value_length);
2070 * Extend the attribute record to be able to store the new attribute
2071 * size. ntfs_attr_record_resize() will not do anything if the size is
2074 if (new_alloc_size < vol->mft_record_size &&
2075 !ntfs_attr_record_resize(m, a,
2076 le16_to_cpu(a->data.resident.value_offset) +
2078 /* The resize succeeded! */
2079 write_lock_irqsave(&ni->size_lock, flags);
2080 ni->allocated_size = le32_to_cpu(a->length) -
2081 le16_to_cpu(a->data.resident.value_offset);
2082 write_unlock_irqrestore(&ni->size_lock, flags);
2083 if (new_data_size >= 0) {
2084 BUG_ON(new_data_size < attr_len);
2085 a->data.resident.value_length =
2086 cpu_to_le32((u32)new_data_size);
2091 * We have to drop all the locks so we can call
2092 * ntfs_attr_make_non_resident(). This could be optimised by try-
2093 * locking the first page cache page and only if that fails dropping
2094 * the locks, locking the page, and redoing all the locking and
2095 * lookups. While this would be a huge optimisation, it is not worth
2096 * it as this is definitely a slow code path.
2098 ntfs_attr_put_search_ctx(ctx);
2099 unmap_mft_record(base_ni);
2100 up_write(&ni->runlist.lock);
2102 * Not enough space in the mft record, try to make the attribute
2103 * non-resident and if successful restart the extension process.
2105 err = ntfs_attr_make_non_resident(ni, attr_len);
2109 * Could not make non-resident. If this is due to this not being
2110 * permitted for this attribute type or there not being enough space,
2111 * try to make other attributes non-resident. Otherwise fail.
2113 if (unlikely(err != -EPERM && err != -ENOSPC)) {
2114 /* Only emit errors when the write will fail completely. */
2115 read_lock_irqsave(&ni->size_lock, flags);
2116 allocated_size = ni->allocated_size;
2117 read_unlock_irqrestore(&ni->size_lock, flags);
2118 if (start < 0 || start >= allocated_size)
2119 ntfs_error(vol->sb, "Cannot extend allocation of "
2120 "inode 0x%lx, attribute type 0x%x, "
2121 "because the conversion from resident "
2122 "to non-resident attribute failed "
2123 "with error code %i.", vi->i_ino,
2124 (unsigned)le32_to_cpu(ni->type), err);
2129 /* TODO: Not implemented from here, abort. */
2130 read_lock_irqsave(&ni->size_lock, flags);
2131 allocated_size = ni->allocated_size;
2132 read_unlock_irqrestore(&ni->size_lock, flags);
2133 if (start < 0 || start >= allocated_size) {
2135 ntfs_error(vol->sb, "Not enough space in the mft "
2136 "record/on disk for the non-resident "
2137 "attribute value. This case is not "
2138 "implemented yet.");
2139 else /* if (err == -EPERM) */
2140 ntfs_error(vol->sb, "This attribute type may not be "
2141 "non-resident. This case is not "
2142 "implemented yet.");
2147 // TODO: Attempt to make other attributes non-resident.
2149 goto do_resident_extend;
2151 * Both the attribute list attribute and the standard information
2152 * attribute must remain in the base inode. Thus, if this is one of
2153 * these attributes, we have to try to move other attributes out into
2154 * extent mft records instead.
2156 if (ni->type == AT_ATTRIBUTE_LIST ||
2157 ni->type == AT_STANDARD_INFORMATION) {
2158 // TODO: Attempt to move other attributes into extent mft
2162 goto do_resident_extend;
2165 // TODO: Attempt to move this attribute to an extent mft record, but
2166 // only if it is not already the only attribute in an mft record in
2167 // which case there would be nothing to gain.
2170 goto do_resident_extend;
2171 /* There is nothing we can do to make enough space. )-: */
2174 do_non_resident_extend:
2175 BUG_ON(!NInoNonResident(ni));
2176 if (new_alloc_size == allocated_size) {
2181 * If the data starts after the end of the old allocation, this is a
2182 * $DATA attribute and sparse attributes are enabled on the volume and
2183 * for this inode, then create a sparse region between the old
2184 * allocated size and the start of the data. Otherwise simply proceed
2185 * with filling the whole space between the old allocated size and the
2186 * new allocated size with clusters.
2188 if ((start >= 0 && start <= allocated_size) || ni->type != AT_DATA ||
2189 !NVolSparseEnabled(vol) || NInoSparseDisabled(ni))
2191 // TODO: This is not implemented yet. We just fill in with real
2192 // clusters for now...
2193 ntfs_debug("Inserting holes is not-implemented yet. Falling back to "
2194 "allocating real clusters instead.");
2196 rl = ni->runlist.rl;
2198 /* Seek to the end of the runlist. */
2202 /* If this attribute extent is not mapped, map it now. */
2203 if (unlikely(!rl || rl->lcn == LCN_RL_NOT_MAPPED ||
2204 (rl->lcn == LCN_ENOENT && rl > ni->runlist.rl &&
2205 (rl-1)->lcn == LCN_RL_NOT_MAPPED))) {
2206 if (!rl && !allocated_size)
2208 rl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2211 if (start < 0 || start >= allocated_size)
2212 ntfs_error(vol->sb, "Cannot extend allocation "
2213 "of inode 0x%lx, attribute "
2214 "type 0x%x, because the "
2215 "mapping of a runlist "
2216 "fragment failed with error "
2217 "code %i.", vi->i_ino,
2218 (unsigned)le32_to_cpu(ni->type),
2224 ni->runlist.rl = rl;
2225 /* Seek to the end of the runlist. */
2230 * We now know the runlist of the last extent is mapped and @rl is at
2231 * the end of the runlist. We want to begin allocating clusters
2232 * starting at the last allocated cluster to reduce fragmentation. If
2233 * there are no valid LCNs in the attribute we let the cluster
2234 * allocator choose the starting cluster.
2236 /* If the last LCN is a hole or simillar seek back to last real LCN. */
2237 while (rl->lcn < 0 && rl > ni->runlist.rl)
2240 // FIXME: Need to implement partial allocations so at least part of the
2241 // write can be performed when start >= 0. (Needed for POSIX write(2)
2243 rl2 = ntfs_cluster_alloc(vol, allocated_size >> vol->cluster_size_bits,
2244 (new_alloc_size - allocated_size) >>
2245 vol->cluster_size_bits, (rl && (rl->lcn >= 0)) ?
2246 rl->lcn + rl->length : -1, DATA_ZONE, true);
2249 if (start < 0 || start >= allocated_size)
2250 ntfs_error(vol->sb, "Cannot extend allocation of "
2251 "inode 0x%lx, attribute type 0x%x, "
2252 "because the allocation of clusters "
2253 "failed with error code %i.", vi->i_ino,
2254 (unsigned)le32_to_cpu(ni->type), err);
2255 if (err != -ENOMEM && err != -ENOSPC)
2259 rl = ntfs_runlists_merge(ni->runlist.rl, rl2);
2262 if (start < 0 || start >= allocated_size)
2263 ntfs_error(vol->sb, "Cannot extend allocation of "
2264 "inode 0x%lx, attribute type 0x%x, "
2265 "because the runlist merge failed "
2266 "with error code %i.", vi->i_ino,
2267 (unsigned)le32_to_cpu(ni->type), err);
2270 if (ntfs_cluster_free_from_rl(vol, rl2)) {
2271 ntfs_error(vol->sb, "Failed to release allocated "
2272 "cluster(s) in error code path. Run "
2273 "chkdsk to recover the lost "
2280 ni->runlist.rl = rl;
2281 ntfs_debug("Allocated 0x%llx clusters.", (long long)(new_alloc_size -
2282 allocated_size) >> vol->cluster_size_bits);
2283 /* Find the runlist element with which the attribute extent starts. */
2284 ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
2285 rl2 = ntfs_rl_find_vcn_nolock(rl, ll);
2287 BUG_ON(!rl2->length);
2288 BUG_ON(rl2->lcn < LCN_HOLE);
2290 /* Get the size for the new mapping pairs array for this extent. */
2291 mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
2292 if (unlikely(mp_size <= 0)) {
2294 if (start < 0 || start >= allocated_size)
2295 ntfs_error(vol->sb, "Cannot extend allocation of "
2296 "inode 0x%lx, attribute type 0x%x, "
2297 "because determining the size for the "
2298 "mapping pairs failed with error code "
2300 (unsigned)le32_to_cpu(ni->type), err);
2304 /* Extend the attribute record to fit the bigger mapping pairs array. */
2305 attr_len = le32_to_cpu(a->length);
2306 err = ntfs_attr_record_resize(m, a, mp_size +
2307 le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2308 if (unlikely(err)) {
2309 BUG_ON(err != -ENOSPC);
2310 // TODO: Deal with this by moving this extent to a new mft
2311 // record or by starting a new extent in a new mft record,
2312 // possibly by extending this extent partially and filling it
2313 // and creating a new extent for the remainder, or by making
2314 // other attributes non-resident and/or by moving other
2315 // attributes out of this mft record.
2316 if (start < 0 || start >= allocated_size)
2317 ntfs_error(vol->sb, "Not enough space in the mft "
2318 "record for the extended attribute "
2319 "record. This case is not "
2320 "implemented yet.");
2325 /* Generate the mapping pairs array directly into the attr record. */
2326 err = ntfs_mapping_pairs_build(vol, (u8*)a +
2327 le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2328 mp_size, rl2, ll, -1, NULL);
2329 if (unlikely(err)) {
2330 if (start < 0 || start >= allocated_size)
2331 ntfs_error(vol->sb, "Cannot extend allocation of "
2332 "inode 0x%lx, attribute type 0x%x, "
2333 "because building the mapping pairs "
2334 "failed with error code %i.", vi->i_ino,
2335 (unsigned)le32_to_cpu(ni->type), err);
2339 /* Update the highest_vcn. */
2340 a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2341 vol->cluster_size_bits) - 1);
2343 * We now have extended the allocated size of the attribute. Reflect
2344 * this in the ntfs_inode structure and the attribute record.
2346 if (a->data.non_resident.lowest_vcn) {
2348 * We are not in the first attribute extent, switch to it, but
2349 * first ensure the changes will make it to disk later.
2351 flush_dcache_mft_record_page(ctx->ntfs_ino);
2352 mark_mft_record_dirty(ctx->ntfs_ino);
2353 ntfs_attr_reinit_search_ctx(ctx);
2354 err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2355 CASE_SENSITIVE, 0, NULL, 0, ctx);
2357 goto restore_undo_alloc;
2358 /* @m is not used any more so no need to set it. */
2361 write_lock_irqsave(&ni->size_lock, flags);
2362 ni->allocated_size = new_alloc_size;
2363 a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2365 * FIXME: This would fail if @ni is a directory, $MFT, or an index,
2366 * since those can have sparse/compressed set. For example can be
2367 * set compressed even though it is not compressed itself and in that
2368 * case the bit means that files are to be created compressed in the
2369 * directory... At present this is ok as this code is only called for
2370 * regular files, and only for their $DATA attribute(s).
2371 * FIXME: The calculation is wrong if we created a hole above. For now
2372 * it does not matter as we never create holes.
2374 if (NInoSparse(ni) || NInoCompressed(ni)) {
2375 ni->itype.compressed.size += new_alloc_size - allocated_size;
2376 a->data.non_resident.compressed_size =
2377 cpu_to_sle64(ni->itype.compressed.size);
2378 vi->i_blocks = ni->itype.compressed.size >> 9;
2380 vi->i_blocks = new_alloc_size >> 9;
2381 write_unlock_irqrestore(&ni->size_lock, flags);
2383 if (new_data_size >= 0) {
2384 BUG_ON(new_data_size <
2385 sle64_to_cpu(a->data.non_resident.data_size));
2386 a->data.non_resident.data_size = cpu_to_sle64(new_data_size);
2389 /* Ensure the changes make it to disk. */
2390 flush_dcache_mft_record_page(ctx->ntfs_ino);
2391 mark_mft_record_dirty(ctx->ntfs_ino);
2393 ntfs_attr_put_search_ctx(ctx);
2394 unmap_mft_record(base_ni);
2395 up_write(&ni->runlist.lock);
2396 ntfs_debug("Done, new_allocated_size 0x%llx.",
2397 (unsigned long long)new_alloc_size);
2398 return new_alloc_size;
2400 if (start < 0 || start >= allocated_size)
2401 ntfs_error(vol->sb, "Cannot complete extension of allocation "
2402 "of inode 0x%lx, attribute type 0x%x, because "
2403 "lookup of first attribute extent failed with "
2404 "error code %i.", vi->i_ino,
2405 (unsigned)le32_to_cpu(ni->type), err);
2408 ntfs_attr_reinit_search_ctx(ctx);
2409 if (ntfs_attr_lookup(ni->type, ni->name, ni->name_len, CASE_SENSITIVE,
2410 allocated_size >> vol->cluster_size_bits, NULL, 0,
2412 ntfs_error(vol->sb, "Failed to find last attribute extent of "
2413 "attribute in error code path. Run chkdsk to "
2415 write_lock_irqsave(&ni->size_lock, flags);
2416 ni->allocated_size = new_alloc_size;
2418 * FIXME: This would fail if @ni is a directory... See above.
2419 * FIXME: The calculation is wrong if we created a hole above.
2420 * For now it does not matter as we never create holes.
2422 if (NInoSparse(ni) || NInoCompressed(ni)) {
2423 ni->itype.compressed.size += new_alloc_size -
2425 vi->i_blocks = ni->itype.compressed.size >> 9;
2427 vi->i_blocks = new_alloc_size >> 9;
2428 write_unlock_irqrestore(&ni->size_lock, flags);
2429 ntfs_attr_put_search_ctx(ctx);
2430 unmap_mft_record(base_ni);
2431 up_write(&ni->runlist.lock);
2433 * The only thing that is now wrong is the allocated size of the
2434 * base attribute extent which chkdsk should be able to fix.
2439 ctx->attr->data.non_resident.highest_vcn = cpu_to_sle64(
2440 (allocated_size >> vol->cluster_size_bits) - 1);
2442 ll = allocated_size >> vol->cluster_size_bits;
2443 if (ntfs_cluster_free(ni, ll, -1, ctx) < 0) {
2444 ntfs_error(vol->sb, "Failed to release allocated cluster(s) "
2445 "in error code path. Run chkdsk to recover "
2446 "the lost cluster(s).");
2452 * If the runlist truncation fails and/or the search context is no
2453 * longer valid, we cannot resize the attribute record or build the
2454 * mapping pairs array thus we mark the inode bad so that no access to
2455 * the freed clusters can happen.
2457 if (ntfs_rl_truncate_nolock(vol, &ni->runlist, ll) || IS_ERR(m)) {
2458 ntfs_error(vol->sb, "Failed to %s in error code path. Run "
2459 "chkdsk to recover.", IS_ERR(m) ?
2460 "restore attribute search context" :
2461 "truncate attribute runlist");
2463 } else if (mp_rebuilt) {
2464 if (ntfs_attr_record_resize(m, a, attr_len)) {
2465 ntfs_error(vol->sb, "Failed to restore attribute "
2466 "record in error code path. Run "
2467 "chkdsk to recover.");
2469 } else /* if (success) */ {
2470 if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
2471 a->data.non_resident.
2472 mapping_pairs_offset), attr_len -
2473 le16_to_cpu(a->data.non_resident.
2474 mapping_pairs_offset), rl2, ll, -1,
2476 ntfs_error(vol->sb, "Failed to restore "
2477 "mapping pairs array in error "
2478 "code path. Run chkdsk to "
2482 flush_dcache_mft_record_page(ctx->ntfs_ino);
2483 mark_mft_record_dirty(ctx->ntfs_ino);
2488 ntfs_attr_put_search_ctx(ctx);
2490 unmap_mft_record(base_ni);
2491 up_write(&ni->runlist.lock);
2493 ntfs_debug("Failed. Returning error code %i.", err);
2498 * ntfs_attr_set - fill (a part of) an attribute with a byte
2499 * @ni: ntfs inode describing the attribute to fill
2500 * @ofs: offset inside the attribute at which to start to fill
2501 * @cnt: number of bytes to fill
2502 * @val: the unsigned 8-bit value with which to fill the attribute
2504 * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at
2505 * byte offset @ofs inside the attribute with the constant byte @val.
2507 * This function is effectively like memset() applied to an ntfs attribute.
2508 * Note thie function actually only operates on the page cache pages belonging
2509 * to the ntfs attribute and it marks them dirty after doing the memset().
2510 * Thus it relies on the vm dirty page write code paths to cause the modified
2511 * pages to be written to the mft record/disk.
2513 * Return 0 on success and -errno on error. An error code of -ESPIPE means
2514 * that @ofs + @cnt were outside the end of the attribute and no write was
2517 int ntfs_attr_set(ntfs_inode *ni, const s64 ofs, const s64 cnt, const u8 val)
2519 ntfs_volume *vol = ni->vol;
2520 struct address_space *mapping;
2524 unsigned start_ofs, end_ofs, size;
2526 ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.",
2527 (long long)ofs, (long long)cnt, val);
2533 * FIXME: Compressed and encrypted attributes are not supported when
2534 * writing and we should never have gotten here for them.
2536 BUG_ON(NInoCompressed(ni));
2537 BUG_ON(NInoEncrypted(ni));
2538 mapping = VFS_I(ni)->i_mapping;
2539 /* Work out the starting index and page offset. */
2540 idx = ofs >> PAGE_SHIFT;
2541 start_ofs = ofs & ~PAGE_MASK;
2542 /* Work out the ending index and page offset. */
2544 end_ofs = end & ~PAGE_MASK;
2545 /* If the end is outside the inode size return -ESPIPE. */
2546 if (unlikely(end > i_size_read(VFS_I(ni)))) {
2547 ntfs_error(vol->sb, "Request exceeds end of attribute.");
2551 /* If there is a first partial page, need to do it the slow way. */
2553 page = read_mapping_page(mapping, idx, NULL);
2555 ntfs_error(vol->sb, "Failed to read first partial "
2556 "page (error, index 0x%lx).", idx);
2557 return PTR_ERR(page);
2560 * If the last page is the same as the first page, need to
2561 * limit the write to the end offset.
2566 kaddr = kmap_atomic(page);
2567 memset(kaddr + start_ofs, val, size - start_ofs);
2568 flush_dcache_page(page);
2569 kunmap_atomic(kaddr);
2570 set_page_dirty(page);
2572 balance_dirty_pages_ratelimited(mapping);
2578 /* Do the whole pages the fast way. */
2579 for (; idx < end; idx++) {
2580 /* Find or create the current page. (The page is locked.) */
2581 page = grab_cache_page(mapping, idx);
2582 if (unlikely(!page)) {
2583 ntfs_error(vol->sb, "Insufficient memory to grab "
2584 "page (index 0x%lx).", idx);
2587 kaddr = kmap_atomic(page);
2588 memset(kaddr, val, PAGE_SIZE);
2589 flush_dcache_page(page);
2590 kunmap_atomic(kaddr);
2592 * If the page has buffers, mark them uptodate since buffer
2593 * state and not page state is definitive in 2.6 kernels.
2595 if (page_has_buffers(page)) {
2596 struct buffer_head *bh, *head;
2598 bh = head = page_buffers(page);
2600 set_buffer_uptodate(bh);
2601 } while ((bh = bh->b_this_page) != head);
2603 /* Now that buffers are uptodate, set the page uptodate, too. */
2604 SetPageUptodate(page);
2606 * Set the page and all its buffers dirty and mark the inode
2607 * dirty, too. The VM will write the page later on.
2609 set_page_dirty(page);
2610 /* Finally unlock and release the page. */
2613 balance_dirty_pages_ratelimited(mapping);
2616 /* If there is a last partial page, need to do it the slow way. */
2618 page = read_mapping_page(mapping, idx, NULL);
2620 ntfs_error(vol->sb, "Failed to read last partial page "
2621 "(error, index 0x%lx).", idx);
2622 return PTR_ERR(page);
2624 kaddr = kmap_atomic(page);
2625 memset(kaddr, val, end_ofs);
2626 flush_dcache_page(page);
2627 kunmap_atomic(kaddr);
2628 set_page_dirty(page);
2630 balance_dirty_pages_ratelimited(mapping);
2634 ntfs_debug("Done.");
2638 #endif /* NTFS_RW */