2 * attrib.c - NTFS attribute operations. Part of the Linux-NTFS project.
4 * Copyright (c) 2001-2005 Anton Altaparmakov
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/swap.h>
36 * ntfs_map_runlist_nolock - map (a part of) a runlist of an ntfs inode
37 * @ni: ntfs inode for which to map (part of) a runlist
38 * @vcn: map runlist part containing this vcn
40 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
42 * Return 0 on success and -errno on error.
44 * Locking: - The runlist must be locked for writing.
45 * - This function modifies the runlist.
47 int ntfs_map_runlist_nolock(ntfs_inode
*ni
, VCN vcn
)
51 ntfs_attr_search_ctx
*ctx
;
55 ntfs_debug("Mapping runlist part containing vcn 0x%llx.",
56 (unsigned long long)vcn
);
60 base_ni
= ni
->ext
.base_ntfs_ino
;
61 mrec
= map_mft_record(base_ni
);
64 ctx
= ntfs_attr_get_search_ctx(base_ni
, mrec
);
69 err
= ntfs_attr_lookup(ni
->type
, ni
->name
, ni
->name_len
,
70 CASE_SENSITIVE
, vcn
, NULL
, 0, ctx
);
72 rl
= ntfs_mapping_pairs_decompress(ni
->vol
, ctx
->attr
,
79 ntfs_attr_put_search_ctx(ctx
);
81 unmap_mft_record(base_ni
);
86 * ntfs_map_runlist - map (a part of) a runlist of an ntfs inode
87 * @ni: ntfs inode for which to map (part of) a runlist
88 * @vcn: map runlist part containing this vcn
90 * Map the part of a runlist containing the @vcn of the ntfs inode @ni.
92 * Return 0 on success and -errno on error.
94 * Locking: - The runlist must be unlocked on entry and is unlocked on return.
95 * - This function takes the runlist lock for writing and modifies the
98 int ntfs_map_runlist(ntfs_inode
*ni
, VCN vcn
)
102 down_write(&ni
->runlist
.lock
);
103 /* Make sure someone else didn't do the work while we were sleeping. */
104 if (likely(ntfs_rl_vcn_to_lcn(ni
->runlist
.rl
, vcn
) <=
106 err
= ntfs_map_runlist_nolock(ni
, vcn
);
107 up_write(&ni
->runlist
.lock
);
112 * ntfs_attr_vcn_to_lcn_nolock - convert a vcn into a lcn given an ntfs inode
113 * @ni: ntfs inode of the attribute whose runlist to search
114 * @vcn: vcn to convert
115 * @write_locked: true if the runlist is locked for writing
117 * Find the virtual cluster number @vcn in the runlist of the ntfs attribute
118 * described by the ntfs inode @ni and return the corresponding logical cluster
121 * If the @vcn is not mapped yet, the attempt is made to map the attribute
122 * extent containing the @vcn and the vcn to lcn conversion is retried.
124 * If @write_locked is true the caller has locked the runlist for writing and
125 * if false for reading.
127 * Since lcns must be >= 0, we use negative return codes with special meaning:
129 * Return code Meaning / Description
130 * ==========================================
131 * LCN_HOLE Hole / not allocated on disk.
132 * LCN_ENOENT There is no such vcn in the runlist, i.e. @vcn is out of bounds.
133 * LCN_ENOMEM Not enough memory to map runlist.
134 * LCN_EIO Critical error (runlist/file is corrupt, i/o error, etc).
136 * Locking: - The runlist must be locked on entry and is left locked on return.
137 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
138 * the lock may be dropped inside the function so you cannot rely on
139 * the runlist still being the same when this function returns.
141 LCN
ntfs_attr_vcn_to_lcn_nolock(ntfs_inode
*ni
, const VCN vcn
,
142 const BOOL write_locked
)
145 BOOL is_retry
= FALSE
;
147 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
148 ni
->mft_no
, (unsigned long long)vcn
,
149 write_locked
? "write" : "read");
151 BUG_ON(!NInoNonResident(ni
));
154 /* Convert vcn to lcn. If that fails map the runlist and retry once. */
155 lcn
= ntfs_rl_vcn_to_lcn(ni
->runlist
.rl
, vcn
);
156 if (likely(lcn
>= LCN_HOLE
)) {
157 ntfs_debug("Done, lcn 0x%llx.", (long long)lcn
);
160 if (lcn
!= LCN_RL_NOT_MAPPED
) {
161 if (lcn
!= LCN_ENOENT
)
163 } else if (!is_retry
) {
167 up_read(&ni
->runlist
.lock
);
168 down_write(&ni
->runlist
.lock
);
169 if (unlikely(ntfs_rl_vcn_to_lcn(ni
->runlist
.rl
, vcn
) !=
170 LCN_RL_NOT_MAPPED
)) {
171 up_write(&ni
->runlist
.lock
);
172 down_read(&ni
->runlist
.lock
);
176 err
= ntfs_map_runlist_nolock(ni
, vcn
);
178 up_write(&ni
->runlist
.lock
);
179 down_read(&ni
->runlist
.lock
);
187 else if (err
== -ENOMEM
)
192 if (lcn
!= LCN_ENOENT
)
193 ntfs_error(ni
->vol
->sb
, "Failed with error code %lli.",
199 * ntfs_attr_find_vcn_nolock - find a vcn in the runlist of an ntfs inode
200 * @ni: ntfs inode describing the runlist to search
202 * @write_locked: true if the runlist is locked for writing
204 * Find the virtual cluster number @vcn in the runlist described by the ntfs
205 * inode @ni and return the address of the runlist element containing the @vcn.
207 * If the @vcn is not mapped yet, the attempt is made to map the attribute
208 * extent containing the @vcn and the vcn to lcn conversion is retried.
210 * If @write_locked is true the caller has locked the runlist for writing and
211 * if false for reading.
213 * Note you need to distinguish between the lcn of the returned runlist element
214 * being >= 0 and LCN_HOLE. In the later case you have to return zeroes on
215 * read and allocate clusters on write.
217 * Return the runlist element containing the @vcn on success and
218 * ERR_PTR(-errno) on error. You need to test the return value with IS_ERR()
219 * to decide if the return is success or failure and PTR_ERR() to get to the
220 * error code if IS_ERR() is true.
222 * The possible error return codes are:
223 * -ENOENT - No such vcn in the runlist, i.e. @vcn is out of bounds.
224 * -ENOMEM - Not enough memory to map runlist.
225 * -EIO - Critical error (runlist/file is corrupt, i/o error, etc).
227 * Locking: - The runlist must be locked on entry and is left locked on return.
228 * - If @write_locked is FALSE, i.e. the runlist is locked for reading,
229 * the lock may be dropped inside the function so you cannot rely on
230 * the runlist still being the same when this function returns.
232 runlist_element
*ntfs_attr_find_vcn_nolock(ntfs_inode
*ni
, const VCN vcn
,
233 const BOOL write_locked
)
237 BOOL is_retry
= FALSE
;
239 ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.",
240 ni
->mft_no
, (unsigned long long)vcn
,
241 write_locked
? "write" : "read");
243 BUG_ON(!NInoNonResident(ni
));
247 if (likely(rl
&& vcn
>= rl
[0].vcn
)) {
248 while (likely(rl
->length
)) {
249 if (unlikely(vcn
< rl
[1].vcn
)) {
250 if (likely(rl
->lcn
>= LCN_HOLE
)) {
258 if (likely(rl
->lcn
!= LCN_RL_NOT_MAPPED
)) {
259 if (likely(rl
->lcn
== LCN_ENOENT
))
265 if (!err
&& !is_retry
) {
267 * The @vcn is in an unmapped region, map the runlist and
271 up_read(&ni
->runlist
.lock
);
272 down_write(&ni
->runlist
.lock
);
273 if (unlikely(ntfs_rl_vcn_to_lcn(ni
->runlist
.rl
, vcn
) !=
274 LCN_RL_NOT_MAPPED
)) {
275 up_write(&ni
->runlist
.lock
);
276 down_read(&ni
->runlist
.lock
);
280 err
= ntfs_map_runlist_nolock(ni
, vcn
);
282 up_write(&ni
->runlist
.lock
);
283 down_read(&ni
->runlist
.lock
);
290 * -EINVAL and -ENOENT coming from a failed mapping attempt are
291 * equivalent to i/o errors for us as they should not happen in
294 if (err
== -EINVAL
|| err
== -ENOENT
)
299 ntfs_error(ni
->vol
->sb
, "Failed with error code %i.", err
);
304 * ntfs_attr_find - find (next) attribute in mft record
305 * @type: attribute type to find
306 * @name: attribute name to find (optional, i.e. NULL means don't care)
307 * @name_len: attribute name length (only needed if @name present)
308 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
309 * @val: attribute value to find (optional, resident attributes only)
310 * @val_len: attribute value length
311 * @ctx: search context with mft record and attribute to search from
313 * You should not need to call this function directly. Use ntfs_attr_lookup()
316 * ntfs_attr_find() takes a search context @ctx as parameter and searches the
317 * mft record specified by @ctx->mrec, beginning at @ctx->attr, for an
318 * attribute of @type, optionally @name and @val.
320 * If the attribute is found, ntfs_attr_find() returns 0 and @ctx->attr will
321 * point to the found attribute.
323 * If the attribute is not found, ntfs_attr_find() returns -ENOENT and
324 * @ctx->attr will point to the attribute before which the attribute being
325 * searched for would need to be inserted if such an action were to be desired.
327 * On actual error, ntfs_attr_find() returns -EIO. In this case @ctx->attr is
328 * undefined and in particular do not rely on it not changing.
330 * If @ctx->is_first is TRUE, the search begins with @ctx->attr itself. If it
331 * is FALSE, the search begins after @ctx->attr.
333 * If @ic is IGNORE_CASE, the @name comparisson is not case sensitive and
334 * @ctx->ntfs_ino must be set to the ntfs inode to which the mft record
335 * @ctx->mrec belongs. This is so we can get at the ntfs volume and hence at
336 * the upcase table. If @ic is CASE_SENSITIVE, the comparison is case
337 * sensitive. When @name is present, @name_len is the @name length in Unicode
340 * If @name is not present (NULL), we assume that the unnamed attribute is
341 * being searched for.
343 * Finally, the resident attribute value @val is looked for, if present. If
344 * @val is not present (NULL), @val_len is ignored.
346 * ntfs_attr_find() only searches the specified mft record and it ignores the
347 * presence of an attribute list attribute (unless it is the one being searched
348 * for, obviously). If you need to take attribute lists into consideration,
349 * use ntfs_attr_lookup() instead (see below). This also means that you cannot
350 * use ntfs_attr_find() to search for extent records of non-resident
351 * attributes, as extents with lowest_vcn != 0 are usually described by the
352 * attribute list attribute only. - Note that it is possible that the first
353 * extent is only in the attribute list while the last extent is in the base
354 * mft record, so do not rely on being able to find the first extent in the
357 * Warning: Never use @val when looking for attribute types which can be
358 * non-resident as this most likely will result in a crash!
360 static int ntfs_attr_find(const ATTR_TYPE type
, const ntfschar
*name
,
361 const u32 name_len
, const IGNORE_CASE_BOOL ic
,
362 const u8
*val
, const u32 val_len
, ntfs_attr_search_ctx
*ctx
)
365 ntfs_volume
*vol
= ctx
->ntfs_ino
->vol
;
366 ntfschar
*upcase
= vol
->upcase
;
367 u32 upcase_len
= vol
->upcase_len
;
370 * Iterate over attributes in mft record starting at @ctx->attr, or the
371 * attribute following that, if @ctx->is_first is TRUE.
375 ctx
->is_first
= FALSE
;
377 a
= (ATTR_RECORD
*)((u8
*)ctx
->attr
+
378 le32_to_cpu(ctx
->attr
->length
));
379 for (;; a
= (ATTR_RECORD
*)((u8
*)a
+ le32_to_cpu(a
->length
))) {
380 if ((u8
*)a
< (u8
*)ctx
->mrec
|| (u8
*)a
> (u8
*)ctx
->mrec
+
381 le32_to_cpu(ctx
->mrec
->bytes_allocated
))
384 if (unlikely(le32_to_cpu(a
->type
) > le32_to_cpu(type
) ||
387 if (unlikely(!a
->length
))
392 * If @name is present, compare the two names. If @name is
393 * missing, assume we want an unnamed attribute.
396 /* The search failed if the found attribute is named. */
399 } else if (!ntfs_are_names_equal(name
, name_len
,
400 (ntfschar
*)((u8
*)a
+ le16_to_cpu(a
->name_offset
)),
401 a
->name_length
, ic
, upcase
, upcase_len
)) {
404 rc
= ntfs_collate_names(name
, name_len
,
406 le16_to_cpu(a
->name_offset
)),
407 a
->name_length
, 1, IGNORE_CASE
,
410 * If @name collates before a->name, there is no
411 * matching attribute.
415 /* If the strings are not equal, continue search. */
418 rc
= ntfs_collate_names(name
, name_len
,
420 le16_to_cpu(a
->name_offset
)),
421 a
->name_length
, 1, CASE_SENSITIVE
,
429 * The names match or @name not present and attribute is
430 * unnamed. If no @val specified, we have found the attribute
435 /* @val is present; compare values. */
439 rc
= memcmp(val
, (u8
*)a
+ le16_to_cpu(
440 a
->data
.resident
.value_offset
),
441 min_t(u32
, val_len
, le32_to_cpu(
442 a
->data
.resident
.value_length
)));
444 * If @val collates before the current attribute's
445 * value, there is no matching attribute.
451 a
->data
.resident
.value_length
);
460 ntfs_error(vol
->sb
, "Inode is corrupt. Run chkdsk.");
466 * load_attribute_list - load an attribute list into memory
467 * @vol: ntfs volume from which to read
468 * @runlist: runlist of the attribute list
469 * @al_start: destination buffer
470 * @size: size of the destination buffer in bytes
471 * @initialized_size: initialized size of the attribute list
473 * Walk the runlist @runlist and load all clusters from it copying them into
474 * the linear buffer @al. The maximum number of bytes copied to @al is @size
475 * bytes. Note, @size does not need to be a multiple of the cluster size. If
476 * @initialized_size is less than @size, the region in @al between
477 * @initialized_size and @size will be zeroed and not read from disk.
479 * Return 0 on success or -errno on error.
481 int load_attribute_list(ntfs_volume
*vol
, runlist
*runlist
, u8
*al_start
,
482 const s64 size
, const s64 initialized_size
)
486 u8
*al_end
= al
+ initialized_size
;
488 struct buffer_head
*bh
;
489 struct super_block
*sb
;
490 unsigned long block_size
;
491 unsigned long block
, max_block
;
493 unsigned char block_size_bits
;
495 ntfs_debug("Entering.");
496 if (!vol
|| !runlist
|| !al
|| size
<= 0 || initialized_size
< 0 ||
497 initialized_size
> size
)
499 if (!initialized_size
) {
504 block_size
= sb
->s_blocksize
;
505 block_size_bits
= sb
->s_blocksize_bits
;
506 down_read(&runlist
->lock
);
508 /* Read all clusters specified by the runlist one run at a time. */
510 lcn
= ntfs_rl_vcn_to_lcn(rl
, rl
->vcn
);
511 ntfs_debug("Reading vcn = 0x%llx, lcn = 0x%llx.",
512 (unsigned long long)rl
->vcn
,
513 (unsigned long long)lcn
);
514 /* The attribute list cannot be sparse. */
516 ntfs_error(sb
, "ntfs_rl_vcn_to_lcn() failed. Cannot "
517 "read attribute list.");
520 block
= lcn
<< vol
->cluster_size_bits
>> block_size_bits
;
521 /* Read the run from device in chunks of block_size bytes. */
522 max_block
= block
+ (rl
->length
<< vol
->cluster_size_bits
>>
524 ntfs_debug("max_block = 0x%lx.", max_block
);
526 ntfs_debug("Reading block = 0x%lx.", block
);
527 bh
= sb_bread(sb
, block
);
529 ntfs_error(sb
, "sb_bread() failed. Cannot "
530 "read attribute list.");
533 if (al
+ block_size
>= al_end
)
535 memcpy(al
, bh
->b_data
, block_size
);
538 } while (++block
< max_block
);
541 if (initialized_size
< size
) {
543 memset(al_start
+ initialized_size
, 0, size
- initialized_size
);
546 up_read(&runlist
->lock
);
553 * Note: The attribute list can be smaller than its allocation
554 * by multiple clusters. This has been encountered by at least
555 * two people running Windows XP, thus we cannot do any
556 * truncation sanity checking here. (AIA)
558 memcpy(al
, bh
->b_data
, al_end
- al
);
560 if (initialized_size
< size
)
566 ntfs_error(sb
, "Attribute list buffer overflow. Read attribute list "
574 * ntfs_external_attr_find - find an attribute in the attribute list of an inode
575 * @type: attribute type to find
576 * @name: attribute name to find (optional, i.e. NULL means don't care)
577 * @name_len: attribute name length (only needed if @name present)
578 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
579 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
580 * @val: attribute value to find (optional, resident attributes only)
581 * @val_len: attribute value length
582 * @ctx: search context with mft record and attribute to search from
584 * You should not need to call this function directly. Use ntfs_attr_lookup()
587 * Find an attribute by searching the attribute list for the corresponding
588 * attribute list entry. Having found the entry, map the mft record if the
589 * attribute is in a different mft record/inode, ntfs_attr_find() the attribute
590 * in there and return it.
592 * On first search @ctx->ntfs_ino must be the base mft record and @ctx must
593 * have been obtained from a call to ntfs_attr_get_search_ctx(). On subsequent
594 * calls @ctx->ntfs_ino can be any extent inode, too (@ctx->base_ntfs_ino is
595 * then the base inode).
597 * After finishing with the attribute/mft record you need to call
598 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
599 * mapped inodes, etc).
601 * If the attribute is found, ntfs_external_attr_find() returns 0 and
602 * @ctx->attr will point to the found attribute. @ctx->mrec will point to the
603 * mft record in which @ctx->attr is located and @ctx->al_entry will point to
604 * the attribute list entry for the attribute.
606 * If the attribute is not found, ntfs_external_attr_find() returns -ENOENT and
607 * @ctx->attr will point to the attribute in the base mft record before which
608 * the attribute being searched for would need to be inserted if such an action
609 * were to be desired. @ctx->mrec will point to the mft record in which
610 * @ctx->attr is located and @ctx->al_entry will point to the attribute list
611 * entry of the attribute before which the attribute being searched for would
612 * need to be inserted if such an action were to be desired.
614 * Thus to insert the not found attribute, one wants to add the attribute to
615 * @ctx->mrec (the base mft record) and if there is not enough space, the
616 * attribute should be placed in a newly allocated extent mft record. The
617 * attribute list entry for the inserted attribute should be inserted in the
618 * attribute list attribute at @ctx->al_entry.
620 * On actual error, ntfs_external_attr_find() returns -EIO. In this case
621 * @ctx->attr is undefined and in particular do not rely on it not changing.
623 static int ntfs_external_attr_find(const ATTR_TYPE type
,
624 const ntfschar
*name
, const u32 name_len
,
625 const IGNORE_CASE_BOOL ic
, const VCN lowest_vcn
,
626 const u8
*val
, const u32 val_len
, ntfs_attr_search_ctx
*ctx
)
628 ntfs_inode
*base_ni
, *ni
;
630 ATTR_LIST_ENTRY
*al_entry
, *next_al_entry
;
631 u8
*al_start
, *al_end
;
636 static const char *es
= " Unmount and run chkdsk.";
639 base_ni
= ctx
->base_ntfs_ino
;
640 ntfs_debug("Entering for inode 0x%lx, type 0x%x.", ni
->mft_no
, type
);
642 /* First call happens with the base mft record. */
643 base_ni
= ctx
->base_ntfs_ino
= ctx
->ntfs_ino
;
644 ctx
->base_mrec
= ctx
->mrec
;
647 ctx
->base_attr
= ctx
->attr
;
651 al_start
= base_ni
->attr_list
;
652 al_end
= al_start
+ base_ni
->attr_list_size
;
654 ctx
->al_entry
= (ATTR_LIST_ENTRY
*)al_start
;
656 * Iterate over entries in attribute list starting at @ctx->al_entry,
657 * or the entry following that, if @ctx->is_first is TRUE.
660 al_entry
= ctx
->al_entry
;
661 ctx
->is_first
= FALSE
;
663 al_entry
= (ATTR_LIST_ENTRY
*)((u8
*)ctx
->al_entry
+
664 le16_to_cpu(ctx
->al_entry
->length
));
665 for (;; al_entry
= next_al_entry
) {
666 /* Out of bounds check. */
667 if ((u8
*)al_entry
< base_ni
->attr_list
||
668 (u8
*)al_entry
> al_end
)
669 break; /* Inode is corrupt. */
670 ctx
->al_entry
= al_entry
;
671 /* Catch the end of the attribute list. */
672 if ((u8
*)al_entry
== al_end
)
674 if (!al_entry
->length
)
676 if ((u8
*)al_entry
+ 6 > al_end
|| (u8
*)al_entry
+
677 le16_to_cpu(al_entry
->length
) > al_end
)
679 next_al_entry
= (ATTR_LIST_ENTRY
*)((u8
*)al_entry
+
680 le16_to_cpu(al_entry
->length
));
681 if (le32_to_cpu(al_entry
->type
) > le32_to_cpu(type
))
683 if (type
!= al_entry
->type
)
686 * If @name is present, compare the two names. If @name is
687 * missing, assume we want an unnamed attribute.
689 al_name_len
= al_entry
->name_length
;
690 al_name
= (ntfschar
*)((u8
*)al_entry
+ al_entry
->name_offset
);
694 } else if (!ntfs_are_names_equal(al_name
, al_name_len
, name
,
695 name_len
, ic
, vol
->upcase
, vol
->upcase_len
)) {
698 rc
= ntfs_collate_names(name
, name_len
, al_name
,
699 al_name_len
, 1, IGNORE_CASE
,
700 vol
->upcase
, vol
->upcase_len
);
702 * If @name collates before al_name, there is no
703 * matching attribute.
707 /* If the strings are not equal, continue search. */
711 * FIXME: Reverse engineering showed 0, IGNORE_CASE but
712 * that is inconsistent with ntfs_attr_find(). The
713 * subsequent rc checks were also different. Perhaps I
714 * made a mistake in one of the two. Need to recheck
715 * which is correct or at least see what is going on...
718 rc
= ntfs_collate_names(name
, name_len
, al_name
,
719 al_name_len
, 1, CASE_SENSITIVE
,
720 vol
->upcase
, vol
->upcase_len
);
727 * The names match or @name not present and attribute is
728 * unnamed. Now check @lowest_vcn. Continue search if the
729 * next attribute list entry still fits @lowest_vcn. Otherwise
730 * we have reached the right one or the search has failed.
732 if (lowest_vcn
&& (u8
*)next_al_entry
>= al_start
&&
733 (u8
*)next_al_entry
+ 6 < al_end
&&
734 (u8
*)next_al_entry
+ le16_to_cpu(
735 next_al_entry
->length
) <= al_end
&&
736 sle64_to_cpu(next_al_entry
->lowest_vcn
) <=
738 next_al_entry
->type
== al_entry
->type
&&
739 next_al_entry
->name_length
== al_name_len
&&
740 ntfs_are_names_equal((ntfschar
*)((u8
*)
742 next_al_entry
->name_offset
),
743 next_al_entry
->name_length
,
744 al_name
, al_name_len
, CASE_SENSITIVE
,
745 vol
->upcase
, vol
->upcase_len
))
747 if (MREF_LE(al_entry
->mft_reference
) == ni
->mft_no
) {
748 if (MSEQNO_LE(al_entry
->mft_reference
) != ni
->seq_no
) {
749 ntfs_error(vol
->sb
, "Found stale mft "
750 "reference in attribute list "
751 "of base inode 0x%lx.%s",
752 base_ni
->mft_no
, es
);
756 } else { /* Mft references do not match. */
757 /* If there is a mapped record unmap it first. */
759 unmap_extent_mft_record(ni
);
760 /* Do we want the base record back? */
761 if (MREF_LE(al_entry
->mft_reference
) ==
763 ni
= ctx
->ntfs_ino
= base_ni
;
764 ctx
->mrec
= ctx
->base_mrec
;
766 /* We want an extent record. */
767 ctx
->mrec
= map_extent_mft_record(base_ni
,
769 al_entry
->mft_reference
), &ni
);
770 if (IS_ERR(ctx
->mrec
)) {
771 ntfs_error(vol
->sb
, "Failed to map "
773 "0x%lx of base inode "
777 base_ni
->mft_no
, es
);
778 err
= PTR_ERR(ctx
->mrec
);
781 /* Cause @ctx to be sanitized below. */
787 ctx
->attr
= (ATTR_RECORD
*)((u8
*)ctx
->mrec
+
788 le16_to_cpu(ctx
->mrec
->attrs_offset
));
791 * ctx->vfs_ino, ctx->mrec, and ctx->attr now point to the
792 * mft record containing the attribute represented by the
796 * We could call into ntfs_attr_find() to find the right
797 * attribute in this mft record but this would be less
798 * efficient and not quite accurate as ntfs_attr_find() ignores
799 * the attribute instance numbers for example which become
800 * important when one plays with attribute lists. Also,
801 * because a proper match has been found in the attribute list
802 * entry above, the comparison can now be optimized. So it is
803 * worth re-implementing a simplified ntfs_attr_find() here.
807 * Use a manual loop so we can still use break and continue
808 * with the same meanings as above.
811 if ((u8
*)a
< (u8
*)ctx
->mrec
|| (u8
*)a
> (u8
*)ctx
->mrec
+
812 le32_to_cpu(ctx
->mrec
->bytes_allocated
))
814 if (a
->type
== AT_END
)
818 if (al_entry
->instance
!= a
->instance
)
821 * If the type and/or the name are mismatched between the
822 * attribute list entry and the attribute record, there is
823 * corruption so we break and return error EIO.
825 if (al_entry
->type
!= a
->type
)
827 if (!ntfs_are_names_equal((ntfschar
*)((u8
*)a
+
828 le16_to_cpu(a
->name_offset
)), a
->name_length
,
829 al_name
, al_name_len
, CASE_SENSITIVE
,
830 vol
->upcase
, vol
->upcase_len
))
834 * If no @val specified or @val specified and it matches, we
837 if (!val
|| (!a
->non_resident
&& le32_to_cpu(
838 a
->data
.resident
.value_length
) == val_len
&&
840 le16_to_cpu(a
->data
.resident
.value_offset
),
842 ntfs_debug("Done, found.");
846 /* Proceed to the next attribute in the current mft record. */
847 a
= (ATTR_RECORD
*)((u8
*)a
+ le32_to_cpu(a
->length
));
848 goto do_next_attr_loop
;
851 ntfs_error(vol
->sb
, "Base inode 0x%lx contains corrupt "
852 "attribute list attribute.%s", base_ni
->mft_no
,
858 unmap_extent_mft_record(ni
);
859 ctx
->ntfs_ino
= base_ni
;
860 ctx
->mrec
= ctx
->base_mrec
;
861 ctx
->attr
= ctx
->base_attr
;
868 * If we were looking for AT_END, we reset the search context @ctx and
869 * use ntfs_attr_find() to seek to the end of the base mft record.
871 if (type
== AT_END
) {
872 ntfs_attr_reinit_search_ctx(ctx
);
873 return ntfs_attr_find(AT_END
, name
, name_len
, ic
, val
, val_len
,
877 * The attribute was not found. Before we return, we want to ensure
878 * @ctx->mrec and @ctx->attr indicate the position at which the
879 * attribute should be inserted in the base mft record. Since we also
880 * want to preserve @ctx->al_entry we cannot reinitialize the search
881 * context using ntfs_attr_reinit_search_ctx() as this would set
882 * @ctx->al_entry to NULL. Thus we do the necessary bits manually (see
883 * ntfs_attr_init_search_ctx() below). Note, we _only_ preserve
884 * @ctx->al_entry as the remaining fields (base_*) are identical to
885 * their non base_ counterparts and we cannot set @ctx->base_attr
886 * correctly yet as we do not know what @ctx->attr will be set to by
887 * the call to ntfs_attr_find() below.
890 unmap_extent_mft_record(ni
);
891 ctx
->mrec
= ctx
->base_mrec
;
892 ctx
->attr
= (ATTR_RECORD
*)((u8
*)ctx
->mrec
+
893 le16_to_cpu(ctx
->mrec
->attrs_offset
));
894 ctx
->is_first
= TRUE
;
895 ctx
->ntfs_ino
= base_ni
;
896 ctx
->base_ntfs_ino
= NULL
;
897 ctx
->base_mrec
= NULL
;
898 ctx
->base_attr
= NULL
;
900 * In case there are multiple matches in the base mft record, need to
901 * keep enumerating until we get an attribute not found response (or
902 * another error), otherwise we would keep returning the same attribute
903 * over and over again and all programs using us for enumeration would
904 * lock up in a tight loop.
907 err
= ntfs_attr_find(type
, name
, name_len
, ic
, val
, val_len
,
910 ntfs_debug("Done, not found.");
915 * ntfs_attr_lookup - find an attribute in an ntfs inode
916 * @type: attribute type to find
917 * @name: attribute name to find (optional, i.e. NULL means don't care)
918 * @name_len: attribute name length (only needed if @name present)
919 * @ic: IGNORE_CASE or CASE_SENSITIVE (ignored if @name not present)
920 * @lowest_vcn: lowest vcn to find (optional, non-resident attributes only)
921 * @val: attribute value to find (optional, resident attributes only)
922 * @val_len: attribute value length
923 * @ctx: search context with mft record and attribute to search from
925 * Find an attribute in an ntfs inode. On first search @ctx->ntfs_ino must
926 * be the base mft record and @ctx must have been obtained from a call to
927 * ntfs_attr_get_search_ctx().
929 * This function transparently handles attribute lists and @ctx is used to
930 * continue searches where they were left off at.
932 * After finishing with the attribute/mft record you need to call
933 * ntfs_attr_put_search_ctx() to cleanup the search context (unmapping any
934 * mapped inodes, etc).
936 * Return 0 if the search was successful and -errno if not.
938 * When 0, @ctx->attr is the found attribute and it is in mft record
939 * @ctx->mrec. If an attribute list attribute is present, @ctx->al_entry is
940 * the attribute list entry of the found attribute.
942 * When -ENOENT, @ctx->attr is the attribute which collates just after the
943 * attribute being searched for, i.e. if one wants to add the attribute to the
944 * mft record this is the correct place to insert it into. If an attribute
945 * list attribute is present, @ctx->al_entry is the attribute list entry which
946 * collates just after the attribute list entry of the attribute being searched
947 * for, i.e. if one wants to add the attribute to the mft record this is the
948 * correct place to insert its attribute list entry into.
950 * When -errno != -ENOENT, an error occured during the lookup. @ctx->attr is
951 * then undefined and in particular you should not rely on it not changing.
953 int ntfs_attr_lookup(const ATTR_TYPE type
, const ntfschar
*name
,
954 const u32 name_len
, const IGNORE_CASE_BOOL ic
,
955 const VCN lowest_vcn
, const u8
*val
, const u32 val_len
,
956 ntfs_attr_search_ctx
*ctx
)
960 ntfs_debug("Entering.");
961 if (ctx
->base_ntfs_ino
)
962 base_ni
= ctx
->base_ntfs_ino
;
964 base_ni
= ctx
->ntfs_ino
;
965 /* Sanity check, just for debugging really. */
967 if (!NInoAttrList(base_ni
) || type
== AT_ATTRIBUTE_LIST
)
968 return ntfs_attr_find(type
, name
, name_len
, ic
, val
, val_len
,
970 return ntfs_external_attr_find(type
, name
, name_len
, ic
, lowest_vcn
,
975 * ntfs_attr_init_search_ctx - initialize an attribute search context
976 * @ctx: attribute search context to initialize
977 * @ni: ntfs inode with which to initialize the search context
978 * @mrec: mft record with which to initialize the search context
980 * Initialize the attribute search context @ctx with @ni and @mrec.
982 static inline void ntfs_attr_init_search_ctx(ntfs_attr_search_ctx
*ctx
,
983 ntfs_inode
*ni
, MFT_RECORD
*mrec
)
985 *ctx
= (ntfs_attr_search_ctx
) {
987 /* Sanity checks are performed elsewhere. */
988 .attr
= (ATTR_RECORD
*)((u8
*)mrec
+
989 le16_to_cpu(mrec
->attrs_offset
)),
996 * ntfs_attr_reinit_search_ctx - reinitialize an attribute search context
997 * @ctx: attribute search context to reinitialize
999 * Reinitialize the attribute search context @ctx, unmapping an associated
1000 * extent mft record if present, and initialize the search context again.
1002 * This is used when a search for a new attribute is being started to reset
1003 * the search context to the beginning.
1005 void ntfs_attr_reinit_search_ctx(ntfs_attr_search_ctx
*ctx
)
1007 if (likely(!ctx
->base_ntfs_ino
)) {
1008 /* No attribute list. */
1009 ctx
->is_first
= TRUE
;
1010 /* Sanity checks are performed elsewhere. */
1011 ctx
->attr
= (ATTR_RECORD
*)((u8
*)ctx
->mrec
+
1012 le16_to_cpu(ctx
->mrec
->attrs_offset
));
1014 * This needs resetting due to ntfs_external_attr_find() which
1015 * can leave it set despite having zeroed ctx->base_ntfs_ino.
1017 ctx
->al_entry
= NULL
;
1019 } /* Attribute list. */
1020 if (ctx
->ntfs_ino
!= ctx
->base_ntfs_ino
)
1021 unmap_extent_mft_record(ctx
->ntfs_ino
);
1022 ntfs_attr_init_search_ctx(ctx
, ctx
->base_ntfs_ino
, ctx
->base_mrec
);
1027 * ntfs_attr_get_search_ctx - allocate/initialize a new attribute search context
1028 * @ni: ntfs inode with which to initialize the search context
1029 * @mrec: mft record with which to initialize the search context
1031 * Allocate a new attribute search context, initialize it with @ni and @mrec,
1032 * and return it. Return NULL if allocation failed.
1034 ntfs_attr_search_ctx
*ntfs_attr_get_search_ctx(ntfs_inode
*ni
, MFT_RECORD
*mrec
)
1036 ntfs_attr_search_ctx
*ctx
;
1038 ctx
= kmem_cache_alloc(ntfs_attr_ctx_cache
, SLAB_NOFS
);
1040 ntfs_attr_init_search_ctx(ctx
, ni
, mrec
);
1045 * ntfs_attr_put_search_ctx - release an attribute search context
1046 * @ctx: attribute search context to free
1048 * Release the attribute search context @ctx, unmapping an associated extent
1049 * mft record if present.
1051 void ntfs_attr_put_search_ctx(ntfs_attr_search_ctx
*ctx
)
1053 if (ctx
->base_ntfs_ino
&& ctx
->ntfs_ino
!= ctx
->base_ntfs_ino
)
1054 unmap_extent_mft_record(ctx
->ntfs_ino
);
1055 kmem_cache_free(ntfs_attr_ctx_cache
, ctx
);
1062 * ntfs_attr_find_in_attrdef - find an attribute in the $AttrDef system file
1063 * @vol: ntfs volume to which the attribute belongs
1064 * @type: attribute type which to find
1066 * Search for the attribute definition record corresponding to the attribute
1067 * @type in the $AttrDef system file.
1069 * Return the attribute type definition record if found and NULL if not found.
1071 static ATTR_DEF
*ntfs_attr_find_in_attrdef(const ntfs_volume
*vol
,
1072 const ATTR_TYPE type
)
1076 BUG_ON(!vol
->attrdef
);
1078 for (ad
= vol
->attrdef
; (u8
*)ad
- (u8
*)vol
->attrdef
<
1079 vol
->attrdef_size
&& ad
->type
; ++ad
) {
1080 /* We have not found it yet, carry on searching. */
1081 if (likely(le32_to_cpu(ad
->type
) < le32_to_cpu(type
)))
1083 /* We found the attribute; return it. */
1084 if (likely(ad
->type
== type
))
1086 /* We have gone too far already. No point in continuing. */
1089 /* Attribute not found. */
1090 ntfs_debug("Attribute type 0x%x not found in $AttrDef.",
1096 * ntfs_attr_size_bounds_check - check a size of an attribute type for validity
1097 * @vol: ntfs volume to which the attribute belongs
1098 * @type: attribute type which to check
1099 * @size: size which to check
1101 * Check whether the @size in bytes is valid for an attribute of @type on the
1102 * ntfs volume @vol. This information is obtained from $AttrDef system file.
1104 * Return 0 if valid, -ERANGE if not valid, or -ENOENT if the attribute is not
1105 * listed in $AttrDef.
1107 int ntfs_attr_size_bounds_check(const ntfs_volume
*vol
, const ATTR_TYPE type
,
1114 * $ATTRIBUTE_LIST has a maximum size of 256kiB, but this is not
1115 * listed in $AttrDef.
1117 if (unlikely(type
== AT_ATTRIBUTE_LIST
&& size
> 256 * 1024))
1119 /* Get the $AttrDef entry for the attribute @type. */
1120 ad
= ntfs_attr_find_in_attrdef(vol
, type
);
1123 /* Do the bounds check. */
1124 if (((sle64_to_cpu(ad
->min_size
) > 0) &&
1125 size
< sle64_to_cpu(ad
->min_size
)) ||
1126 ((sle64_to_cpu(ad
->max_size
) > 0) && size
>
1127 sle64_to_cpu(ad
->max_size
)))
1133 * ntfs_attr_can_be_non_resident - check if an attribute can be non-resident
1134 * @vol: ntfs volume to which the attribute belongs
1135 * @type: attribute type which to check
1137 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1138 * be non-resident. This information is obtained from $AttrDef system file.
1140 * Return 0 if the attribute is allowed to be non-resident, -EPERM if not, and
1141 * -ENOENT if the attribute is not listed in $AttrDef.
1143 int ntfs_attr_can_be_non_resident(const ntfs_volume
*vol
, const ATTR_TYPE type
)
1147 /* Find the attribute definition record in $AttrDef. */
1148 ad
= ntfs_attr_find_in_attrdef(vol
, type
);
1151 /* Check the flags and return the result. */
1152 if (ad
->flags
& ATTR_DEF_RESIDENT
)
1158 * ntfs_attr_can_be_resident - check if an attribute can be resident
1159 * @vol: ntfs volume to which the attribute belongs
1160 * @type: attribute type which to check
1162 * Check whether the attribute of @type on the ntfs volume @vol is allowed to
1163 * be resident. This information is derived from our ntfs knowledge and may
1164 * not be completely accurate, especially when user defined attributes are
1165 * present. Basically we allow everything to be resident except for index
1166 * allocation and $EA attributes.
1168 * Return 0 if the attribute is allowed to be non-resident and -EPERM if not.
1170 * Warning: In the system file $MFT the attribute $Bitmap must be non-resident
1171 * otherwise windows will not boot (blue screen of death)! We cannot
1172 * check for this here as we do not know which inode's $Bitmap is
1173 * being asked about so the caller needs to special case this.
1175 int ntfs_attr_can_be_resident(const ntfs_volume
*vol
, const ATTR_TYPE type
)
1177 if (type
== AT_INDEX_ALLOCATION
|| type
== AT_EA
)
1183 * ntfs_attr_record_resize - resize an attribute record
1184 * @m: mft record containing attribute record
1185 * @a: attribute record to resize
1186 * @new_size: new size in bytes to which to resize the attribute record @a
1188 * Resize the attribute record @a, i.e. the resident part of the attribute, in
1189 * the mft record @m to @new_size bytes.
1191 * Return 0 on success and -errno on error. The following error codes are
1193 * -ENOSPC - Not enough space in the mft record @m to perform the resize.
1195 * Note: On error, no modifications have been performed whatsoever.
1197 * Warning: If you make a record smaller without having copied all the data you
1198 * are interested in the data may be overwritten.
1200 int ntfs_attr_record_resize(MFT_RECORD
*m
, ATTR_RECORD
*a
, u32 new_size
)
1202 ntfs_debug("Entering for new_size %u.", new_size
);
1203 /* Align to 8 bytes if it is not already done. */
1205 new_size
= (new_size
+ 7) & ~7;
1206 /* If the actual attribute length has changed, move things around. */
1207 if (new_size
!= le32_to_cpu(a
->length
)) {
1208 u32 new_muse
= le32_to_cpu(m
->bytes_in_use
) -
1209 le32_to_cpu(a
->length
) + new_size
;
1210 /* Not enough space in this mft record. */
1211 if (new_muse
> le32_to_cpu(m
->bytes_allocated
))
1213 /* Move attributes following @a to their new location. */
1214 memmove((u8
*)a
+ new_size
, (u8
*)a
+ le32_to_cpu(a
->length
),
1215 le32_to_cpu(m
->bytes_in_use
) - ((u8
*)a
-
1216 (u8
*)m
) - le32_to_cpu(a
->length
));
1217 /* Adjust @m to reflect the change in used space. */
1218 m
->bytes_in_use
= cpu_to_le32(new_muse
);
1219 /* Adjust @a to reflect the new size. */
1220 if (new_size
>= offsetof(ATTR_REC
, length
) + sizeof(a
->length
))
1221 a
->length
= cpu_to_le32(new_size
);
1227 * ntfs_attr_make_non_resident - convert a resident to a non-resident attribute
1228 * @ni: ntfs inode describing the attribute to convert
1230 * Convert the resident ntfs attribute described by the ntfs inode @ni to a
1233 * Return 0 on success and -errno on error. The following error return codes
1235 * -EPERM - The attribute is not allowed to be non-resident.
1236 * -ENOMEM - Not enough memory.
1237 * -ENOSPC - Not enough disk space.
1238 * -EINVAL - Attribute not defined on the volume.
1239 * -EIO - I/o error or other error.
1240 * Note that -ENOSPC is also returned in the case that there is not enough
1241 * space in the mft record to do the conversion. This can happen when the mft
1242 * record is already very full. The caller is responsible for trying to make
1243 * space in the mft record and trying again. FIXME: Do we need a separate
1244 * error return code for this kind of -ENOSPC or is it always worth trying
1245 * again in case the attribute may then fit in a resident state so no need to
1246 * make it non-resident at all? Ho-hum... (AIA)
1248 * NOTE to self: No changes in the attribute list are required to move from
1249 * a resident to a non-resident attribute.
1251 * Locking: - The caller must hold i_sem on the inode.
1253 int ntfs_attr_make_non_resident(ntfs_inode
*ni
)
1256 struct inode
*vi
= VFS_I(ni
);
1257 ntfs_volume
*vol
= ni
->vol
;
1258 ntfs_inode
*base_ni
;
1261 ntfs_attr_search_ctx
*ctx
;
1263 runlist_element
*rl
;
1265 unsigned long flags
;
1266 int mp_size
, mp_ofs
, name_ofs
, arec_size
, err
, err2
;
1268 u8 old_res_attr_flags
;
1270 /* Check that the attribute is allowed to be non-resident. */
1271 err
= ntfs_attr_can_be_non_resident(vol
, ni
->type
);
1272 if (unlikely(err
)) {
1274 ntfs_debug("Attribute is not allowed to be "
1277 ntfs_debug("Attribute not defined on the NTFS "
1282 * The size needs to be aligned to a cluster boundary for allocation
1285 new_size
= (i_size_read(vi
) + vol
->cluster_size
- 1) &
1286 ~(vol
->cluster_size
- 1);
1288 runlist_element
*rl2
;
1291 * Will need the page later and since the page lock nests
1292 * outside all ntfs locks, we need to get the page now.
1294 page
= find_or_create_page(vi
->i_mapping
, 0,
1295 mapping_gfp_mask(vi
->i_mapping
));
1296 if (unlikely(!page
))
1298 /* Start by allocating clusters to hold the attribute value. */
1299 rl
= ntfs_cluster_alloc(vol
, 0, new_size
>>
1300 vol
->cluster_size_bits
, -1, DATA_ZONE
);
1303 ntfs_debug("Failed to allocate cluster%s, error code "
1304 "%i.\n", (new_size
>>
1305 vol
->cluster_size_bits
) > 1 ? "s" : "",
1309 /* Change the runlist terminator to LCN_ENOENT. */
1313 BUG_ON(rl2
->lcn
!= LCN_RL_NOT_MAPPED
);
1314 rl2
->lcn
= LCN_ENOENT
;
1319 /* Determine the size of the mapping pairs array. */
1320 mp_size
= ntfs_get_size_for_mapping_pairs(vol
, rl
, 0);
1321 if (unlikely(mp_size
< 0)) {
1323 ntfs_debug("Failed to get size for mapping pairs array, error "
1327 down_write(&ni
->runlist
.lock
);
1331 base_ni
= ni
->ext
.base_ntfs_ino
;
1332 m
= map_mft_record(base_ni
);
1339 ctx
= ntfs_attr_get_search_ctx(base_ni
, m
);
1340 if (unlikely(!ctx
)) {
1344 err
= ntfs_attr_lookup(ni
->type
, ni
->name
, ni
->name_len
,
1345 CASE_SENSITIVE
, 0, NULL
, 0, ctx
);
1346 if (unlikely(err
)) {
1353 BUG_ON(NInoNonResident(ni
));
1354 BUG_ON(a
->non_resident
);
1356 * Calculate new offsets for the name and the mapping pairs array.
1357 * We assume the attribute is not compressed or sparse.
1359 name_ofs
= (offsetof(ATTR_REC
,
1360 data
.non_resident
.compressed_size
) + 7) & ~7;
1361 mp_ofs
= (name_ofs
+ a
->name_length
* sizeof(ntfschar
) + 7) & ~7;
1363 * Determine the size of the resident part of the now non-resident
1366 arec_size
= (mp_ofs
+ mp_size
+ 7) & ~7;
1368 * If the page is not uptodate bring it uptodate by copying from the
1371 attr_size
= le32_to_cpu(a
->data
.resident
.value_length
);
1372 BUG_ON(attr_size
!= i_size_read(vi
));
1373 if (page
&& !PageUptodate(page
)) {
1374 kaddr
= kmap_atomic(page
, KM_USER0
);
1375 memcpy(kaddr
, (u8
*)a
+
1376 le16_to_cpu(a
->data
.resident
.value_offset
),
1378 memset(kaddr
+ attr_size
, 0, PAGE_CACHE_SIZE
- attr_size
);
1379 kunmap_atomic(kaddr
, KM_USER0
);
1380 flush_dcache_page(page
);
1381 SetPageUptodate(page
);
1383 /* Backup the attribute flag. */
1384 old_res_attr_flags
= a
->data
.resident
.flags
;
1385 /* Resize the resident part of the attribute record. */
1386 err
= ntfs_attr_record_resize(m
, a
, arec_size
);
1390 * Convert the resident part of the attribute record to describe a
1391 * non-resident attribute.
1393 a
->non_resident
= 1;
1394 /* Move the attribute name if it exists and update the offset. */
1396 memmove((u8
*)a
+ name_ofs
, (u8
*)a
+ le16_to_cpu(a
->name_offset
),
1397 a
->name_length
* sizeof(ntfschar
));
1398 a
->name_offset
= cpu_to_le16(name_ofs
);
1400 * FIXME: For now just clear all of these as we do not support them
1403 a
->flags
&= cpu_to_le16(0xffff & ~le16_to_cpu(ATTR_IS_SPARSE
|
1404 ATTR_IS_ENCRYPTED
| ATTR_COMPRESSION_MASK
));
1405 /* Setup the fields specific to non-resident attributes. */
1406 a
->data
.non_resident
.lowest_vcn
= 0;
1407 a
->data
.non_resident
.highest_vcn
= cpu_to_sle64((new_size
- 1) >>
1408 vol
->cluster_size_bits
);
1409 a
->data
.non_resident
.mapping_pairs_offset
= cpu_to_le16(mp_ofs
);
1410 a
->data
.non_resident
.compression_unit
= 0;
1411 memset(&a
->data
.non_resident
.reserved
, 0,
1412 sizeof(a
->data
.non_resident
.reserved
));
1413 a
->data
.non_resident
.allocated_size
= cpu_to_sle64(new_size
);
1414 a
->data
.non_resident
.data_size
=
1415 a
->data
.non_resident
.initialized_size
=
1416 cpu_to_sle64(attr_size
);
1417 /* Generate the mapping pairs array into the attribute record. */
1418 err
= ntfs_mapping_pairs_build(vol
, (u8
*)a
+ mp_ofs
,
1419 arec_size
- mp_ofs
, rl
, 0, NULL
);
1420 if (unlikely(err
)) {
1421 ntfs_debug("Failed to build mapping pairs, error code %i.",
1425 /* Setup the in-memory attribute structure to be non-resident. */
1427 * FIXME: For now just clear all of these as we do not support them
1430 NInoClearSparse(ni
);
1431 NInoClearEncrypted(ni
);
1432 NInoClearCompressed(ni
);
1433 ni
->runlist
.rl
= rl
;
1434 write_lock_irqsave(&ni
->size_lock
, flags
);
1435 ni
->allocated_size
= new_size
;
1436 write_unlock_irqrestore(&ni
->size_lock
, flags
);
1438 * This needs to be last since the address space operations ->readpage
1439 * and ->writepage can run concurrently with us as they are not
1440 * serialized on i_sem. Note, we are not allowed to fail once we flip
1441 * this switch, which is another reason to do this last.
1443 NInoSetNonResident(ni
);
1444 /* Mark the mft record dirty, so it gets written back. */
1445 flush_dcache_mft_record_page(ctx
->ntfs_ino
);
1446 mark_mft_record_dirty(ctx
->ntfs_ino
);
1447 ntfs_attr_put_search_ctx(ctx
);
1448 unmap_mft_record(base_ni
);
1449 up_write(&ni
->runlist
.lock
);
1451 set_page_dirty(page
);
1453 mark_page_accessed(page
);
1454 page_cache_release(page
);
1456 ntfs_debug("Done.");
1459 /* Convert the attribute back into a resident attribute. */
1460 a
->non_resident
= 0;
1461 /* Move the attribute name if it exists and update the offset. */
1462 name_ofs
= (offsetof(ATTR_RECORD
, data
.resident
.reserved
) +
1463 sizeof(a
->data
.resident
.reserved
) + 7) & ~7;
1465 memmove((u8
*)a
+ name_ofs
, (u8
*)a
+ le16_to_cpu(a
->name_offset
),
1466 a
->name_length
* sizeof(ntfschar
));
1467 mp_ofs
= (name_ofs
+ a
->name_length
* sizeof(ntfschar
) + 7) & ~7;
1468 a
->name_offset
= cpu_to_le16(name_ofs
);
1469 arec_size
= (mp_ofs
+ attr_size
+ 7) & ~7;
1470 /* Resize the resident part of the attribute record. */
1471 err2
= ntfs_attr_record_resize(m
, a
, arec_size
);
1472 if (unlikely(err2
)) {
1474 * This cannot happen (well if memory corruption is at work it
1475 * could happen in theory), but deal with it as well as we can.
1476 * If the old size is too small, truncate the attribute,
1477 * otherwise simply give it a larger allocated size.
1478 * FIXME: Should check whether chkdsk complains when the
1479 * allocated size is much bigger than the resident value size.
1481 arec_size
= le32_to_cpu(a
->length
);
1482 if ((mp_ofs
+ attr_size
) > arec_size
) {
1484 attr_size
= arec_size
- mp_ofs
;
1485 ntfs_error(vol
->sb
, "Failed to undo partial resident "
1486 "to non-resident attribute "
1487 "conversion. Truncating inode 0x%lx, "
1488 "attribute type 0x%x from %i bytes to "
1489 "%i bytes to maintain metadata "
1490 "consistency. THIS MEANS YOU ARE "
1491 "LOSING %i BYTES DATA FROM THIS %s.",
1493 (unsigned)le32_to_cpu(ni
->type
),
1494 err2
, attr_size
, err2
- attr_size
,
1495 ((ni
->type
== AT_DATA
) &&
1496 !ni
->name_len
) ? "FILE": "ATTRIBUTE");
1497 write_lock_irqsave(&ni
->size_lock
, flags
);
1498 ni
->initialized_size
= attr_size
;
1499 i_size_write(vi
, attr_size
);
1500 write_unlock_irqrestore(&ni
->size_lock
, flags
);
1503 /* Setup the fields specific to resident attributes. */
1504 a
->data
.resident
.value_length
= cpu_to_le32(attr_size
);
1505 a
->data
.resident
.value_offset
= cpu_to_le16(mp_ofs
);
1506 a
->data
.resident
.flags
= old_res_attr_flags
;
1507 memset(&a
->data
.resident
.reserved
, 0,
1508 sizeof(a
->data
.resident
.reserved
));
1509 /* Copy the data from the page back to the attribute value. */
1511 kaddr
= kmap_atomic(page
, KM_USER0
);
1512 memcpy((u8
*)a
+ mp_ofs
, kaddr
, attr_size
);
1513 kunmap_atomic(kaddr
, KM_USER0
);
1515 /* Setup the allocated size in the ntfs inode in case it changed. */
1516 write_lock_irqsave(&ni
->size_lock
, flags
);
1517 ni
->allocated_size
= arec_size
- mp_ofs
;
1518 write_unlock_irqrestore(&ni
->size_lock
, flags
);
1519 /* Mark the mft record dirty, so it gets written back. */
1520 flush_dcache_mft_record_page(ctx
->ntfs_ino
);
1521 mark_mft_record_dirty(ctx
->ntfs_ino
);
1524 ntfs_attr_put_search_ctx(ctx
);
1526 unmap_mft_record(base_ni
);
1527 ni
->runlist
.rl
= NULL
;
1528 up_write(&ni
->runlist
.lock
);
1531 if (ntfs_cluster_free_from_rl(vol
, rl
) < 0) {
1532 ntfs_error(vol
->sb
, "Failed to release allocated "
1533 "cluster(s) in error code path. Run "
1534 "chkdsk to recover the lost "
1541 page_cache_release(page
);
1549 * ntfs_attr_set - fill (a part of) an attribute with a byte
1550 * @ni: ntfs inode describing the attribute to fill
1551 * @ofs: offset inside the attribute at which to start to fill
1552 * @cnt: number of bytes to fill
1553 * @val: the unsigned 8-bit value with which to fill the attribute
1555 * Fill @cnt bytes of the attribute described by the ntfs inode @ni starting at
1556 * byte offset @ofs inside the attribute with the constant byte @val.
1558 * This function is effectively like memset() applied to an ntfs attribute.
1559 * Note thie function actually only operates on the page cache pages belonging
1560 * to the ntfs attribute and it marks them dirty after doing the memset().
1561 * Thus it relies on the vm dirty page write code paths to cause the modified
1562 * pages to be written to the mft record/disk.
1564 * Return 0 on success and -errno on error. An error code of -ESPIPE means
1565 * that @ofs + @cnt were outside the end of the attribute and no write was
1568 int ntfs_attr_set(ntfs_inode
*ni
, const s64 ofs
, const s64 cnt
, const u8 val
)
1570 ntfs_volume
*vol
= ni
->vol
;
1571 struct address_space
*mapping
;
1575 unsigned int start_ofs
, end_ofs
, size
;
1577 ntfs_debug("Entering for ofs 0x%llx, cnt 0x%llx, val 0x%hx.",
1578 (long long)ofs
, (long long)cnt
, val
);
1583 mapping
= VFS_I(ni
)->i_mapping
;
1584 /* Work out the starting index and page offset. */
1585 idx
= ofs
>> PAGE_CACHE_SHIFT
;
1586 start_ofs
= ofs
& ~PAGE_CACHE_MASK
;
1587 /* Work out the ending index and page offset. */
1589 end_ofs
= end
& ~PAGE_CACHE_MASK
;
1590 /* If the end is outside the inode size return -ESPIPE. */
1591 if (unlikely(end
> i_size_read(VFS_I(ni
)))) {
1592 ntfs_error(vol
->sb
, "Request exceeds end of attribute.");
1595 end
>>= PAGE_CACHE_SHIFT
;
1596 /* If there is a first partial page, need to do it the slow way. */
1598 page
= read_cache_page(mapping
, idx
,
1599 (filler_t
*)mapping
->a_ops
->readpage
, NULL
);
1601 ntfs_error(vol
->sb
, "Failed to read first partial "
1602 "page (sync error, index 0x%lx).", idx
);
1603 return PTR_ERR(page
);
1605 wait_on_page_locked(page
);
1606 if (unlikely(!PageUptodate(page
))) {
1607 ntfs_error(vol
->sb
, "Failed to read first partial page "
1608 "(async error, index 0x%lx).", idx
);
1609 page_cache_release(page
);
1610 return PTR_ERR(page
);
1613 * If the last page is the same as the first page, need to
1614 * limit the write to the end offset.
1616 size
= PAGE_CACHE_SIZE
;
1619 kaddr
= kmap_atomic(page
, KM_USER0
);
1620 memset(kaddr
+ start_ofs
, val
, size
- start_ofs
);
1621 flush_dcache_page(page
);
1622 kunmap_atomic(kaddr
, KM_USER0
);
1623 set_page_dirty(page
);
1624 page_cache_release(page
);
1629 /* Do the whole pages the fast way. */
1630 for (; idx
< end
; idx
++) {
1631 /* Find or create the current page. (The page is locked.) */
1632 page
= grab_cache_page(mapping
, idx
);
1633 if (unlikely(!page
)) {
1634 ntfs_error(vol
->sb
, "Insufficient memory to grab "
1635 "page (index 0x%lx).", idx
);
1638 kaddr
= kmap_atomic(page
, KM_USER0
);
1639 memset(kaddr
, val
, PAGE_CACHE_SIZE
);
1640 flush_dcache_page(page
);
1641 kunmap_atomic(kaddr
, KM_USER0
);
1643 * If the page has buffers, mark them uptodate since buffer
1644 * state and not page state is definitive in 2.6 kernels.
1646 if (page_has_buffers(page
)) {
1647 struct buffer_head
*bh
, *head
;
1649 bh
= head
= page_buffers(page
);
1651 set_buffer_uptodate(bh
);
1652 } while ((bh
= bh
->b_this_page
) != head
);
1654 /* Now that buffers are uptodate, set the page uptodate, too. */
1655 SetPageUptodate(page
);
1657 * Set the page and all its buffers dirty and mark the inode
1658 * dirty, too. The VM will write the page later on.
1660 set_page_dirty(page
);
1661 /* Finally unlock and release the page. */
1663 page_cache_release(page
);
1665 /* If there is a last partial page, need to do it the slow way. */
1667 page
= read_cache_page(mapping
, idx
,
1668 (filler_t
*)mapping
->a_ops
->readpage
, NULL
);
1670 ntfs_error(vol
->sb
, "Failed to read last partial page "
1671 "(sync error, index 0x%lx).", idx
);
1672 return PTR_ERR(page
);
1674 wait_on_page_locked(page
);
1675 if (unlikely(!PageUptodate(page
))) {
1676 ntfs_error(vol
->sb
, "Failed to read last partial page "
1677 "(async error, index 0x%lx).", idx
);
1678 page_cache_release(page
);
1679 return PTR_ERR(page
);
1681 kaddr
= kmap_atomic(page
, KM_USER0
);
1682 memset(kaddr
, val
, end_ofs
);
1683 flush_dcache_page(page
);
1684 kunmap_atomic(kaddr
, KM_USER0
);
1685 set_page_dirty(page
);
1686 page_cache_release(page
);
1689 ntfs_debug("Done.");
1693 #endif /* NTFS_RW */