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TOMOYO Linux Cross Reference
Linux/fs/ntfs/inode.c

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  1 // SPDX-License-Identifier: GPL-2.0-or-later
  2 /**
  3  * inode.c - NTFS kernel inode handling.
  4  *
  5  * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc.
  6  */
  7 
  8 #include <linux/buffer_head.h>
  9 #include <linux/fs.h>
 10 #include <linux/mm.h>
 11 #include <linux/mount.h>
 12 #include <linux/mutex.h>
 13 #include <linux/pagemap.h>
 14 #include <linux/quotaops.h>
 15 #include <linux/slab.h>
 16 #include <linux/log2.h>
 17 
 18 #include "aops.h"
 19 #include "attrib.h"
 20 #include "bitmap.h"
 21 #include "dir.h"
 22 #include "debug.h"
 23 #include "inode.h"
 24 #include "lcnalloc.h"
 25 #include "malloc.h"
 26 #include "mft.h"
 27 #include "time.h"
 28 #include "ntfs.h"
 29 
 30 /**
 31  * ntfs_test_inode - compare two (possibly fake) inodes for equality
 32  * @vi:         vfs inode which to test
 33  * @na:         ntfs attribute which is being tested with
 34  *
 35  * Compare the ntfs attribute embedded in the ntfs specific part of the vfs
 36  * inode @vi for equality with the ntfs attribute @na.
 37  *
 38  * If searching for the normal file/directory inode, set @na->type to AT_UNUSED.
 39  * @na->name and @na->name_len are then ignored.
 40  *
 41  * Return 1 if the attributes match and 0 if not.
 42  *
 43  * NOTE: This function runs with the inode_hash_lock spin lock held so it is not
 44  * allowed to sleep.
 45  */
 46 int ntfs_test_inode(struct inode *vi, ntfs_attr *na)
 47 {
 48         ntfs_inode *ni;
 49 
 50         if (vi->i_ino != na->mft_no)
 51                 return 0;
 52         ni = NTFS_I(vi);
 53         /* If !NInoAttr(ni), @vi is a normal file or directory inode. */
 54         if (likely(!NInoAttr(ni))) {
 55                 /* If not looking for a normal inode this is a mismatch. */
 56                 if (unlikely(na->type != AT_UNUSED))
 57                         return 0;
 58         } else {
 59                 /* A fake inode describing an attribute. */
 60                 if (ni->type != na->type)
 61                         return 0;
 62                 if (ni->name_len != na->name_len)
 63                         return 0;
 64                 if (na->name_len && memcmp(ni->name, na->name,
 65                                 na->name_len * sizeof(ntfschar)))
 66                         return 0;
 67         }
 68         /* Match! */
 69         return 1;
 70 }
 71 
 72 /**
 73  * ntfs_init_locked_inode - initialize an inode
 74  * @vi:         vfs inode to initialize
 75  * @na:         ntfs attribute which to initialize @vi to
 76  *
 77  * Initialize the vfs inode @vi with the values from the ntfs attribute @na in
 78  * order to enable ntfs_test_inode() to do its work.
 79  *
 80  * If initializing the normal file/directory inode, set @na->type to AT_UNUSED.
 81  * In that case, @na->name and @na->name_len should be set to NULL and 0,
 82  * respectively. Although that is not strictly necessary as
 83  * ntfs_read_locked_inode() will fill them in later.
 84  *
 85  * Return 0 on success and -errno on error.
 86  *
 87  * NOTE: This function runs with the inode->i_lock spin lock held so it is not
 88  * allowed to sleep. (Hence the GFP_ATOMIC allocation.)
 89  */
 90 static int ntfs_init_locked_inode(struct inode *vi, ntfs_attr *na)
 91 {
 92         ntfs_inode *ni = NTFS_I(vi);
 93 
 94         vi->i_ino = na->mft_no;
 95 
 96         ni->type = na->type;
 97         if (na->type == AT_INDEX_ALLOCATION)
 98                 NInoSetMstProtected(ni);
 99 
100         ni->name = na->name;
101         ni->name_len = na->name_len;
102 
103         /* If initializing a normal inode, we are done. */
104         if (likely(na->type == AT_UNUSED)) {
105                 BUG_ON(na->name);
106                 BUG_ON(na->name_len);
107                 return 0;
108         }
109 
110         /* It is a fake inode. */
111         NInoSetAttr(ni);
112 
113         /*
114          * We have I30 global constant as an optimization as it is the name
115          * in >99.9% of named attributes! The other <0.1% incur a GFP_ATOMIC
116          * allocation but that is ok. And most attributes are unnamed anyway,
117          * thus the fraction of named attributes with name != I30 is actually
118          * absolutely tiny.
119          */
120         if (na->name_len && na->name != I30) {
121                 unsigned int i;
122 
123                 BUG_ON(!na->name);
124                 i = na->name_len * sizeof(ntfschar);
125                 ni->name = kmalloc(i + sizeof(ntfschar), GFP_ATOMIC);
126                 if (!ni->name)
127                         return -ENOMEM;
128                 memcpy(ni->name, na->name, i);
129                 ni->name[na->name_len] = 0;
130         }
131         return 0;
132 }
133 
134 typedef int (*set_t)(struct inode *, void *);
135 static int ntfs_read_locked_inode(struct inode *vi);
136 static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi);
137 static int ntfs_read_locked_index_inode(struct inode *base_vi,
138                 struct inode *vi);
139 
140 /**
141  * ntfs_iget - obtain a struct inode corresponding to a specific normal inode
142  * @sb:         super block of mounted volume
143  * @mft_no:     mft record number / inode number to obtain
144  *
145  * Obtain the struct inode corresponding to a specific normal inode (i.e. a
146  * file or directory).
147  *
148  * If the inode is in the cache, it is just returned with an increased
149  * reference count. Otherwise, a new struct inode is allocated and initialized,
150  * and finally ntfs_read_locked_inode() is called to read in the inode and
151  * fill in the remainder of the inode structure.
152  *
153  * Return the struct inode on success. Check the return value with IS_ERR() and
154  * if true, the function failed and the error code is obtained from PTR_ERR().
155  */
156 struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no)
157 {
158         struct inode *vi;
159         int err;
160         ntfs_attr na;
161 
162         na.mft_no = mft_no;
163         na.type = AT_UNUSED;
164         na.name = NULL;
165         na.name_len = 0;
166 
167         vi = iget5_locked(sb, mft_no, (test_t)ntfs_test_inode,
168                         (set_t)ntfs_init_locked_inode, &na);
169         if (unlikely(!vi))
170                 return ERR_PTR(-ENOMEM);
171 
172         err = 0;
173 
174         /* If this is a freshly allocated inode, need to read it now. */
175         if (vi->i_state & I_NEW) {
176                 err = ntfs_read_locked_inode(vi);
177                 unlock_new_inode(vi);
178         }
179         /*
180          * There is no point in keeping bad inodes around if the failure was
181          * due to ENOMEM. We want to be able to retry again later.
182          */
183         if (unlikely(err == -ENOMEM)) {
184                 iput(vi);
185                 vi = ERR_PTR(err);
186         }
187         return vi;
188 }
189 
190 /**
191  * ntfs_attr_iget - obtain a struct inode corresponding to an attribute
192  * @base_vi:    vfs base inode containing the attribute
193  * @type:       attribute type
194  * @name:       Unicode name of the attribute (NULL if unnamed)
195  * @name_len:   length of @name in Unicode characters (0 if unnamed)
196  *
197  * Obtain the (fake) struct inode corresponding to the attribute specified by
198  * @type, @name, and @name_len, which is present in the base mft record
199  * specified by the vfs inode @base_vi.
200  *
201  * If the attribute inode is in the cache, it is just returned with an
202  * increased reference count. Otherwise, a new struct inode is allocated and
203  * initialized, and finally ntfs_read_locked_attr_inode() is called to read the
204  * attribute and fill in the inode structure.
205  *
206  * Note, for index allocation attributes, you need to use ntfs_index_iget()
207  * instead of ntfs_attr_iget() as working with indices is a lot more complex.
208  *
209  * Return the struct inode of the attribute inode on success. Check the return
210  * value with IS_ERR() and if true, the function failed and the error code is
211  * obtained from PTR_ERR().
212  */
213 struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
214                 ntfschar *name, u32 name_len)
215 {
216         struct inode *vi;
217         int err;
218         ntfs_attr na;
219 
220         /* Make sure no one calls ntfs_attr_iget() for indices. */
221         BUG_ON(type == AT_INDEX_ALLOCATION);
222 
223         na.mft_no = base_vi->i_ino;
224         na.type = type;
225         na.name = name;
226         na.name_len = name_len;
227 
228         vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
229                         (set_t)ntfs_init_locked_inode, &na);
230         if (unlikely(!vi))
231                 return ERR_PTR(-ENOMEM);
232 
233         err = 0;
234 
235         /* If this is a freshly allocated inode, need to read it now. */
236         if (vi->i_state & I_NEW) {
237                 err = ntfs_read_locked_attr_inode(base_vi, vi);
238                 unlock_new_inode(vi);
239         }
240         /*
241          * There is no point in keeping bad attribute inodes around. This also
242          * simplifies things in that we never need to check for bad attribute
243          * inodes elsewhere.
244          */
245         if (unlikely(err)) {
246                 iput(vi);
247                 vi = ERR_PTR(err);
248         }
249         return vi;
250 }
251 
252 /**
253  * ntfs_index_iget - obtain a struct inode corresponding to an index
254  * @base_vi:    vfs base inode containing the index related attributes
255  * @name:       Unicode name of the index
256  * @name_len:   length of @name in Unicode characters
257  *
258  * Obtain the (fake) struct inode corresponding to the index specified by @name
259  * and @name_len, which is present in the base mft record specified by the vfs
260  * inode @base_vi.
261  *
262  * If the index inode is in the cache, it is just returned with an increased
263  * reference count.  Otherwise, a new struct inode is allocated and
264  * initialized, and finally ntfs_read_locked_index_inode() is called to read
265  * the index related attributes and fill in the inode structure.
266  *
267  * Return the struct inode of the index inode on success. Check the return
268  * value with IS_ERR() and if true, the function failed and the error code is
269  * obtained from PTR_ERR().
270  */
271 struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
272                 u32 name_len)
273 {
274         struct inode *vi;
275         int err;
276         ntfs_attr na;
277 
278         na.mft_no = base_vi->i_ino;
279         na.type = AT_INDEX_ALLOCATION;
280         na.name = name;
281         na.name_len = name_len;
282 
283         vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
284                         (set_t)ntfs_init_locked_inode, &na);
285         if (unlikely(!vi))
286                 return ERR_PTR(-ENOMEM);
287 
288         err = 0;
289 
290         /* If this is a freshly allocated inode, need to read it now. */
291         if (vi->i_state & I_NEW) {
292                 err = ntfs_read_locked_index_inode(base_vi, vi);
293                 unlock_new_inode(vi);
294         }
295         /*
296          * There is no point in keeping bad index inodes around.  This also
297          * simplifies things in that we never need to check for bad index
298          * inodes elsewhere.
299          */
300         if (unlikely(err)) {
301                 iput(vi);
302                 vi = ERR_PTR(err);
303         }
304         return vi;
305 }
306 
307 struct inode *ntfs_alloc_big_inode(struct super_block *sb)
308 {
309         ntfs_inode *ni;
310 
311         ntfs_debug("Entering.");
312         ni = kmem_cache_alloc(ntfs_big_inode_cache, GFP_NOFS);
313         if (likely(ni != NULL)) {
314                 ni->state = 0;
315                 return VFS_I(ni);
316         }
317         ntfs_error(sb, "Allocation of NTFS big inode structure failed.");
318         return NULL;
319 }
320 
321 void ntfs_free_big_inode(struct inode *inode)
322 {
323         kmem_cache_free(ntfs_big_inode_cache, NTFS_I(inode));
324 }
325 
326 static inline ntfs_inode *ntfs_alloc_extent_inode(void)
327 {
328         ntfs_inode *ni;
329 
330         ntfs_debug("Entering.");
331         ni = kmem_cache_alloc(ntfs_inode_cache, GFP_NOFS);
332         if (likely(ni != NULL)) {
333                 ni->state = 0;
334                 return ni;
335         }
336         ntfs_error(NULL, "Allocation of NTFS inode structure failed.");
337         return NULL;
338 }
339 
340 static void ntfs_destroy_extent_inode(ntfs_inode *ni)
341 {
342         ntfs_debug("Entering.");
343         BUG_ON(ni->page);
344         if (!atomic_dec_and_test(&ni->count))
345                 BUG();
346         kmem_cache_free(ntfs_inode_cache, ni);
347 }
348 
349 /*
350  * The attribute runlist lock has separate locking rules from the
351  * normal runlist lock, so split the two lock-classes:
352  */
353 static struct lock_class_key attr_list_rl_lock_class;
354 
355 /**
356  * __ntfs_init_inode - initialize ntfs specific part of an inode
357  * @sb:         super block of mounted volume
358  * @ni:         freshly allocated ntfs inode which to initialize
359  *
360  * Initialize an ntfs inode to defaults.
361  *
362  * NOTE: ni->mft_no, ni->state, ni->type, ni->name, and ni->name_len are left
363  * untouched. Make sure to initialize them elsewhere.
364  *
365  * Return zero on success and -ENOMEM on error.
366  */
367 void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni)
368 {
369         ntfs_debug("Entering.");
370         rwlock_init(&ni->size_lock);
371         ni->initialized_size = ni->allocated_size = 0;
372         ni->seq_no = 0;
373         atomic_set(&ni->count, 1);
374         ni->vol = NTFS_SB(sb);
375         ntfs_init_runlist(&ni->runlist);
376         mutex_init(&ni->mrec_lock);
377         ni->page = NULL;
378         ni->page_ofs = 0;
379         ni->attr_list_size = 0;
380         ni->attr_list = NULL;
381         ntfs_init_runlist(&ni->attr_list_rl);
382         lockdep_set_class(&ni->attr_list_rl.lock,
383                                 &attr_list_rl_lock_class);
384         ni->itype.index.block_size = 0;
385         ni->itype.index.vcn_size = 0;
386         ni->itype.index.collation_rule = 0;
387         ni->itype.index.block_size_bits = 0;
388         ni->itype.index.vcn_size_bits = 0;
389         mutex_init(&ni->extent_lock);
390         ni->nr_extents = 0;
391         ni->ext.base_ntfs_ino = NULL;
392 }
393 
394 /*
395  * Extent inodes get MFT-mapped in a nested way, while the base inode
396  * is still mapped. Teach this nesting to the lock validator by creating
397  * a separate class for nested inode's mrec_lock's:
398  */
399 static struct lock_class_key extent_inode_mrec_lock_key;
400 
401 inline ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
402                 unsigned long mft_no)
403 {
404         ntfs_inode *ni = ntfs_alloc_extent_inode();
405 
406         ntfs_debug("Entering.");
407         if (likely(ni != NULL)) {
408                 __ntfs_init_inode(sb, ni);
409                 lockdep_set_class(&ni->mrec_lock, &extent_inode_mrec_lock_key);
410                 ni->mft_no = mft_no;
411                 ni->type = AT_UNUSED;
412                 ni->name = NULL;
413                 ni->name_len = 0;
414         }
415         return ni;
416 }
417 
418 /**
419  * ntfs_is_extended_system_file - check if a file is in the $Extend directory
420  * @ctx:        initialized attribute search context
421  *
422  * Search all file name attributes in the inode described by the attribute
423  * search context @ctx and check if any of the names are in the $Extend system
424  * directory.
425  *
426  * Return values:
427  *         1: file is in $Extend directory
428  *         0: file is not in $Extend directory
429  *    -errno: failed to determine if the file is in the $Extend directory
430  */
431 static int ntfs_is_extended_system_file(ntfs_attr_search_ctx *ctx)
432 {
433         int nr_links, err;
434 
435         /* Restart search. */
436         ntfs_attr_reinit_search_ctx(ctx);
437 
438         /* Get number of hard links. */
439         nr_links = le16_to_cpu(ctx->mrec->link_count);
440 
441         /* Loop through all hard links. */
442         while (!(err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0, NULL, 0,
443                         ctx))) {
444                 FILE_NAME_ATTR *file_name_attr;
445                 ATTR_RECORD *attr = ctx->attr;
446                 u8 *p, *p2;
447 
448                 nr_links--;
449                 /*
450                  * Maximum sanity checking as we are called on an inode that
451                  * we suspect might be corrupt.
452                  */
453                 p = (u8*)attr + le32_to_cpu(attr->length);
454                 if (p < (u8*)ctx->mrec || (u8*)p > (u8*)ctx->mrec +
455                                 le32_to_cpu(ctx->mrec->bytes_in_use)) {
456 err_corrupt_attr:
457                         ntfs_error(ctx->ntfs_ino->vol->sb, "Corrupt file name "
458                                         "attribute. You should run chkdsk.");
459                         return -EIO;
460                 }
461                 if (attr->non_resident) {
462                         ntfs_error(ctx->ntfs_ino->vol->sb, "Non-resident file "
463                                         "name. You should run chkdsk.");
464                         return -EIO;
465                 }
466                 if (attr->flags) {
467                         ntfs_error(ctx->ntfs_ino->vol->sb, "File name with "
468                                         "invalid flags. You should run "
469                                         "chkdsk.");
470                         return -EIO;
471                 }
472                 if (!(attr->data.resident.flags & RESIDENT_ATTR_IS_INDEXED)) {
473                         ntfs_error(ctx->ntfs_ino->vol->sb, "Unindexed file "
474                                         "name. You should run chkdsk.");
475                         return -EIO;
476                 }
477                 file_name_attr = (FILE_NAME_ATTR*)((u8*)attr +
478                                 le16_to_cpu(attr->data.resident.value_offset));
479                 p2 = (u8*)attr + le32_to_cpu(attr->data.resident.value_length);
480                 if (p2 < (u8*)attr || p2 > p)
481                         goto err_corrupt_attr;
482                 /* This attribute is ok, but is it in the $Extend directory? */
483                 if (MREF_LE(file_name_attr->parent_directory) == FILE_Extend)
484                         return 1;       /* YES, it's an extended system file. */
485         }
486         if (unlikely(err != -ENOENT))
487                 return err;
488         if (unlikely(nr_links)) {
489                 ntfs_error(ctx->ntfs_ino->vol->sb, "Inode hard link count "
490                                 "doesn't match number of name attributes. You "
491                                 "should run chkdsk.");
492                 return -EIO;
493         }
494         return 0;       /* NO, it is not an extended system file. */
495 }
496 
497 /**
498  * ntfs_read_locked_inode - read an inode from its device
499  * @vi:         inode to read
500  *
501  * ntfs_read_locked_inode() is called from ntfs_iget() to read the inode
502  * described by @vi into memory from the device.
503  *
504  * The only fields in @vi that we need to/can look at when the function is
505  * called are i_sb, pointing to the mounted device's super block, and i_ino,
506  * the number of the inode to load.
507  *
508  * ntfs_read_locked_inode() maps, pins and locks the mft record number i_ino
509  * for reading and sets up the necessary @vi fields as well as initializing
510  * the ntfs inode.
511  *
512  * Q: What locks are held when the function is called?
513  * A: i_state has I_NEW set, hence the inode is locked, also
514  *    i_count is set to 1, so it is not going to go away
515  *    i_flags is set to 0 and we have no business touching it.  Only an ioctl()
516  *    is allowed to write to them. We should of course be honouring them but
517  *    we need to do that using the IS_* macros defined in include/linux/fs.h.
518  *    In any case ntfs_read_locked_inode() has nothing to do with i_flags.
519  *
520  * Return 0 on success and -errno on error.  In the error case, the inode will
521  * have had make_bad_inode() executed on it.
522  */
523 static int ntfs_read_locked_inode(struct inode *vi)
524 {
525         ntfs_volume *vol = NTFS_SB(vi->i_sb);
526         ntfs_inode *ni;
527         struct inode *bvi;
528         MFT_RECORD *m;
529         ATTR_RECORD *a;
530         STANDARD_INFORMATION *si;
531         ntfs_attr_search_ctx *ctx;
532         int err = 0;
533 
534         ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
535 
536         /* Setup the generic vfs inode parts now. */
537         vi->i_uid = vol->uid;
538         vi->i_gid = vol->gid;
539         vi->i_mode = 0;
540 
541         /*
542          * Initialize the ntfs specific part of @vi special casing
543          * FILE_MFT which we need to do at mount time.
544          */
545         if (vi->i_ino != FILE_MFT)
546                 ntfs_init_big_inode(vi);
547         ni = NTFS_I(vi);
548 
549         m = map_mft_record(ni);
550         if (IS_ERR(m)) {
551                 err = PTR_ERR(m);
552                 goto err_out;
553         }
554         ctx = ntfs_attr_get_search_ctx(ni, m);
555         if (!ctx) {
556                 err = -ENOMEM;
557                 goto unm_err_out;
558         }
559 
560         if (!(m->flags & MFT_RECORD_IN_USE)) {
561                 ntfs_error(vi->i_sb, "Inode is not in use!");
562                 goto unm_err_out;
563         }
564         if (m->base_mft_record) {
565                 ntfs_error(vi->i_sb, "Inode is an extent inode!");
566                 goto unm_err_out;
567         }
568 
569         /* Transfer information from mft record into vfs and ntfs inodes. */
570         vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
571 
572         /*
573          * FIXME: Keep in mind that link_count is two for files which have both
574          * a long file name and a short file name as separate entries, so if
575          * we are hiding short file names this will be too high. Either we need
576          * to account for the short file names by subtracting them or we need
577          * to make sure we delete files even though i_nlink is not zero which
578          * might be tricky due to vfs interactions. Need to think about this
579          * some more when implementing the unlink command.
580          */
581         set_nlink(vi, le16_to_cpu(m->link_count));
582         /*
583          * FIXME: Reparse points can have the directory bit set even though
584          * they would be S_IFLNK. Need to deal with this further below when we
585          * implement reparse points / symbolic links but it will do for now.
586          * Also if not a directory, it could be something else, rather than
587          * a regular file. But again, will do for now.
588          */
589         /* Everyone gets all permissions. */
590         vi->i_mode |= S_IRWXUGO;
591         /* If read-only, no one gets write permissions. */
592         if (IS_RDONLY(vi))
593                 vi->i_mode &= ~S_IWUGO;
594         if (m->flags & MFT_RECORD_IS_DIRECTORY) {
595                 vi->i_mode |= S_IFDIR;
596                 /*
597                  * Apply the directory permissions mask set in the mount
598                  * options.
599                  */
600                 vi->i_mode &= ~vol->dmask;
601                 /* Things break without this kludge! */
602                 if (vi->i_nlink > 1)
603                         set_nlink(vi, 1);
604         } else {
605                 vi->i_mode |= S_IFREG;
606                 /* Apply the file permissions mask set in the mount options. */
607                 vi->i_mode &= ~vol->fmask;
608         }
609         /*
610          * Find the standard information attribute in the mft record. At this
611          * stage we haven't setup the attribute list stuff yet, so this could
612          * in fact fail if the standard information is in an extent record, but
613          * I don't think this actually ever happens.
614          */
615         err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0, 0, 0, NULL, 0,
616                         ctx);
617         if (unlikely(err)) {
618                 if (err == -ENOENT) {
619                         /*
620                          * TODO: We should be performing a hot fix here (if the
621                          * recover mount option is set) by creating a new
622                          * attribute.
623                          */
624                         ntfs_error(vi->i_sb, "$STANDARD_INFORMATION attribute "
625                                         "is missing.");
626                 }
627                 goto unm_err_out;
628         }
629         a = ctx->attr;
630         /* Get the standard information attribute value. */
631         si = (STANDARD_INFORMATION*)((u8*)a +
632                         le16_to_cpu(a->data.resident.value_offset));
633 
634         /* Transfer information from the standard information into vi. */
635         /*
636          * Note: The i_?times do not quite map perfectly onto the NTFS times,
637          * but they are close enough, and in the end it doesn't really matter
638          * that much...
639          */
640         /*
641          * mtime is the last change of the data within the file. Not changed
642          * when only metadata is changed, e.g. a rename doesn't affect mtime.
643          */
644         vi->i_mtime = ntfs2utc(si->last_data_change_time);
645         /*
646          * ctime is the last change of the metadata of the file. This obviously
647          * always changes, when mtime is changed. ctime can be changed on its
648          * own, mtime is then not changed, e.g. when a file is renamed.
649          */
650         vi->i_ctime = ntfs2utc(si->last_mft_change_time);
651         /*
652          * Last access to the data within the file. Not changed during a rename
653          * for example but changed whenever the file is written to.
654          */
655         vi->i_atime = ntfs2utc(si->last_access_time);
656 
657         /* Find the attribute list attribute if present. */
658         ntfs_attr_reinit_search_ctx(ctx);
659         err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
660         if (err) {
661                 if (unlikely(err != -ENOENT)) {
662                         ntfs_error(vi->i_sb, "Failed to lookup attribute list "
663                                         "attribute.");
664                         goto unm_err_out;
665                 }
666         } else /* if (!err) */ {
667                 if (vi->i_ino == FILE_MFT)
668                         goto skip_attr_list_load;
669                 ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
670                 NInoSetAttrList(ni);
671                 a = ctx->attr;
672                 if (a->flags & ATTR_COMPRESSION_MASK) {
673                         ntfs_error(vi->i_sb, "Attribute list attribute is "
674                                         "compressed.");
675                         goto unm_err_out;
676                 }
677                 if (a->flags & ATTR_IS_ENCRYPTED ||
678                                 a->flags & ATTR_IS_SPARSE) {
679                         if (a->non_resident) {
680                                 ntfs_error(vi->i_sb, "Non-resident attribute "
681                                                 "list attribute is encrypted/"
682                                                 "sparse.");
683                                 goto unm_err_out;
684                         }
685                         ntfs_warning(vi->i_sb, "Resident attribute list "
686                                         "attribute in inode 0x%lx is marked "
687                                         "encrypted/sparse which is not true.  "
688                                         "However, Windows allows this and "
689                                         "chkdsk does not detect or correct it "
690                                         "so we will just ignore the invalid "
691                                         "flags and pretend they are not set.",
692                                         vi->i_ino);
693                 }
694                 /* Now allocate memory for the attribute list. */
695                 ni->attr_list_size = (u32)ntfs_attr_size(a);
696                 ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
697                 if (!ni->attr_list) {
698                         ntfs_error(vi->i_sb, "Not enough memory to allocate "
699                                         "buffer for attribute list.");
700                         err = -ENOMEM;
701                         goto unm_err_out;
702                 }
703                 if (a->non_resident) {
704                         NInoSetAttrListNonResident(ni);
705                         if (a->data.non_resident.lowest_vcn) {
706                                 ntfs_error(vi->i_sb, "Attribute list has non "
707                                                 "zero lowest_vcn.");
708                                 goto unm_err_out;
709                         }
710                         /*
711                          * Setup the runlist. No need for locking as we have
712                          * exclusive access to the inode at this time.
713                          */
714                         ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
715                                         a, NULL);
716                         if (IS_ERR(ni->attr_list_rl.rl)) {
717                                 err = PTR_ERR(ni->attr_list_rl.rl);
718                                 ni->attr_list_rl.rl = NULL;
719                                 ntfs_error(vi->i_sb, "Mapping pairs "
720                                                 "decompression failed.");
721                                 goto unm_err_out;
722                         }
723                         /* Now load the attribute list. */
724                         if ((err = load_attribute_list(vol, &ni->attr_list_rl,
725                                         ni->attr_list, ni->attr_list_size,
726                                         sle64_to_cpu(a->data.non_resident.
727                                         initialized_size)))) {
728                                 ntfs_error(vi->i_sb, "Failed to load "
729                                                 "attribute list attribute.");
730                                 goto unm_err_out;
731                         }
732                 } else /* if (!a->non_resident) */ {
733                         if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
734                                         + le32_to_cpu(
735                                         a->data.resident.value_length) >
736                                         (u8*)ctx->mrec + vol->mft_record_size) {
737                                 ntfs_error(vi->i_sb, "Corrupt attribute list "
738                                                 "in inode.");
739                                 goto unm_err_out;
740                         }
741                         /* Now copy the attribute list. */
742                         memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
743                                         a->data.resident.value_offset),
744                                         le32_to_cpu(
745                                         a->data.resident.value_length));
746                 }
747         }
748 skip_attr_list_load:
749         /*
750          * If an attribute list is present we now have the attribute list value
751          * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
752          */
753         if (S_ISDIR(vi->i_mode)) {
754                 loff_t bvi_size;
755                 ntfs_inode *bni;
756                 INDEX_ROOT *ir;
757                 u8 *ir_end, *index_end;
758 
759                 /* It is a directory, find index root attribute. */
760                 ntfs_attr_reinit_search_ctx(ctx);
761                 err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
762                                 0, NULL, 0, ctx);
763                 if (unlikely(err)) {
764                         if (err == -ENOENT) {
765                                 // FIXME: File is corrupt! Hot-fix with empty
766                                 // index root attribute if recovery option is
767                                 // set.
768                                 ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
769                                                 "is missing.");
770                         }
771                         goto unm_err_out;
772                 }
773                 a = ctx->attr;
774                 /* Set up the state. */
775                 if (unlikely(a->non_resident)) {
776                         ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
777                                         "resident.");
778                         goto unm_err_out;
779                 }
780                 /* Ensure the attribute name is placed before the value. */
781                 if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
782                                 le16_to_cpu(a->data.resident.value_offset)))) {
783                         ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
784                                         "placed after the attribute value.");
785                         goto unm_err_out;
786                 }
787                 /*
788                  * Compressed/encrypted index root just means that the newly
789                  * created files in that directory should be created compressed/
790                  * encrypted. However index root cannot be both compressed and
791                  * encrypted.
792                  */
793                 if (a->flags & ATTR_COMPRESSION_MASK)
794                         NInoSetCompressed(ni);
795                 if (a->flags & ATTR_IS_ENCRYPTED) {
796                         if (a->flags & ATTR_COMPRESSION_MASK) {
797                                 ntfs_error(vi->i_sb, "Found encrypted and "
798                                                 "compressed attribute.");
799                                 goto unm_err_out;
800                         }
801                         NInoSetEncrypted(ni);
802                 }
803                 if (a->flags & ATTR_IS_SPARSE)
804                         NInoSetSparse(ni);
805                 ir = (INDEX_ROOT*)((u8*)a +
806                                 le16_to_cpu(a->data.resident.value_offset));
807                 ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
808                 if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
809                         ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
810                                         "corrupt.");
811                         goto unm_err_out;
812                 }
813                 index_end = (u8*)&ir->index +
814                                 le32_to_cpu(ir->index.index_length);
815                 if (index_end > ir_end) {
816                         ntfs_error(vi->i_sb, "Directory index is corrupt.");
817                         goto unm_err_out;
818                 }
819                 if (ir->type != AT_FILE_NAME) {
820                         ntfs_error(vi->i_sb, "Indexed attribute is not "
821                                         "$FILE_NAME.");
822                         goto unm_err_out;
823                 }
824                 if (ir->collation_rule != COLLATION_FILE_NAME) {
825                         ntfs_error(vi->i_sb, "Index collation rule is not "
826                                         "COLLATION_FILE_NAME.");
827                         goto unm_err_out;
828                 }
829                 ni->itype.index.collation_rule = ir->collation_rule;
830                 ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
831                 if (ni->itype.index.block_size &
832                                 (ni->itype.index.block_size - 1)) {
833                         ntfs_error(vi->i_sb, "Index block size (%u) is not a "
834                                         "power of two.",
835                                         ni->itype.index.block_size);
836                         goto unm_err_out;
837                 }
838                 if (ni->itype.index.block_size > PAGE_SIZE) {
839                         ntfs_error(vi->i_sb, "Index block size (%u) > "
840                                         "PAGE_SIZE (%ld) is not "
841                                         "supported.  Sorry.",
842                                         ni->itype.index.block_size,
843                                         PAGE_SIZE);
844                         err = -EOPNOTSUPP;
845                         goto unm_err_out;
846                 }
847                 if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
848                         ntfs_error(vi->i_sb, "Index block size (%u) < "
849                                         "NTFS_BLOCK_SIZE (%i) is not "
850                                         "supported.  Sorry.",
851                                         ni->itype.index.block_size,
852                                         NTFS_BLOCK_SIZE);
853                         err = -EOPNOTSUPP;
854                         goto unm_err_out;
855                 }
856                 ni->itype.index.block_size_bits =
857                                 ffs(ni->itype.index.block_size) - 1;
858                 /* Determine the size of a vcn in the directory index. */
859                 if (vol->cluster_size <= ni->itype.index.block_size) {
860                         ni->itype.index.vcn_size = vol->cluster_size;
861                         ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
862                 } else {
863                         ni->itype.index.vcn_size = vol->sector_size;
864                         ni->itype.index.vcn_size_bits = vol->sector_size_bits;
865                 }
866 
867                 /* Setup the index allocation attribute, even if not present. */
868                 NInoSetMstProtected(ni);
869                 ni->type = AT_INDEX_ALLOCATION;
870                 ni->name = I30;
871                 ni->name_len = 4;
872 
873                 if (!(ir->index.flags & LARGE_INDEX)) {
874                         /* No index allocation. */
875                         vi->i_size = ni->initialized_size =
876                                         ni->allocated_size = 0;
877                         /* We are done with the mft record, so we release it. */
878                         ntfs_attr_put_search_ctx(ctx);
879                         unmap_mft_record(ni);
880                         m = NULL;
881                         ctx = NULL;
882                         goto skip_large_dir_stuff;
883                 } /* LARGE_INDEX: Index allocation present. Setup state. */
884                 NInoSetIndexAllocPresent(ni);
885                 /* Find index allocation attribute. */
886                 ntfs_attr_reinit_search_ctx(ctx);
887                 err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
888                                 CASE_SENSITIVE, 0, NULL, 0, ctx);
889                 if (unlikely(err)) {
890                         if (err == -ENOENT)
891                                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
892                                                 "attribute is not present but "
893                                                 "$INDEX_ROOT indicated it is.");
894                         else
895                                 ntfs_error(vi->i_sb, "Failed to lookup "
896                                                 "$INDEX_ALLOCATION "
897                                                 "attribute.");
898                         goto unm_err_out;
899                 }
900                 a = ctx->attr;
901                 if (!a->non_resident) {
902                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
903                                         "is resident.");
904                         goto unm_err_out;
905                 }
906                 /*
907                  * Ensure the attribute name is placed before the mapping pairs
908                  * array.
909                  */
910                 if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
911                                 le16_to_cpu(
912                                 a->data.non_resident.mapping_pairs_offset)))) {
913                         ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
914                                         "is placed after the mapping pairs "
915                                         "array.");
916                         goto unm_err_out;
917                 }
918                 if (a->flags & ATTR_IS_ENCRYPTED) {
919                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
920                                         "is encrypted.");
921                         goto unm_err_out;
922                 }
923                 if (a->flags & ATTR_IS_SPARSE) {
924                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
925                                         "is sparse.");
926                         goto unm_err_out;
927                 }
928                 if (a->flags & ATTR_COMPRESSION_MASK) {
929                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
930                                         "is compressed.");
931                         goto unm_err_out;
932                 }
933                 if (a->data.non_resident.lowest_vcn) {
934                         ntfs_error(vi->i_sb, "First extent of "
935                                         "$INDEX_ALLOCATION attribute has non "
936                                         "zero lowest_vcn.");
937                         goto unm_err_out;
938                 }
939                 vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
940                 ni->initialized_size = sle64_to_cpu(
941                                 a->data.non_resident.initialized_size);
942                 ni->allocated_size = sle64_to_cpu(
943                                 a->data.non_resident.allocated_size);
944                 /*
945                  * We are done with the mft record, so we release it. Otherwise
946                  * we would deadlock in ntfs_attr_iget().
947                  */
948                 ntfs_attr_put_search_ctx(ctx);
949                 unmap_mft_record(ni);
950                 m = NULL;
951                 ctx = NULL;
952                 /* Get the index bitmap attribute inode. */
953                 bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
954                 if (IS_ERR(bvi)) {
955                         ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
956                         err = PTR_ERR(bvi);
957                         goto unm_err_out;
958                 }
959                 bni = NTFS_I(bvi);
960                 if (NInoCompressed(bni) || NInoEncrypted(bni) ||
961                                 NInoSparse(bni)) {
962                         ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
963                                         "and/or encrypted and/or sparse.");
964                         goto iput_unm_err_out;
965                 }
966                 /* Consistency check bitmap size vs. index allocation size. */
967                 bvi_size = i_size_read(bvi);
968                 if ((bvi_size << 3) < (vi->i_size >>
969                                 ni->itype.index.block_size_bits)) {
970                         ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
971                                         "for index allocation (0x%llx).",
972                                         bvi_size << 3, vi->i_size);
973                         goto iput_unm_err_out;
974                 }
975                 /* No longer need the bitmap attribute inode. */
976                 iput(bvi);
977 skip_large_dir_stuff:
978                 /* Setup the operations for this inode. */
979                 vi->i_op = &ntfs_dir_inode_ops;
980                 vi->i_fop = &ntfs_dir_ops;
981                 vi->i_mapping->a_ops = &ntfs_mst_aops;
982         } else {
983                 /* It is a file. */
984                 ntfs_attr_reinit_search_ctx(ctx);
985 
986                 /* Setup the data attribute, even if not present. */
987                 ni->type = AT_DATA;
988                 ni->name = NULL;
989                 ni->name_len = 0;
990 
991                 /* Find first extent of the unnamed data attribute. */
992                 err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
993                 if (unlikely(err)) {
994                         vi->i_size = ni->initialized_size =
995                                         ni->allocated_size = 0;
996                         if (err != -ENOENT) {
997                                 ntfs_error(vi->i_sb, "Failed to lookup $DATA "
998                                                 "attribute.");
999                                 goto unm_err_out;
1000                         }
1001                         /*
1002                          * FILE_Secure does not have an unnamed $DATA
1003                          * attribute, so we special case it here.
1004                          */
1005                         if (vi->i_ino == FILE_Secure)
1006                                 goto no_data_attr_special_case;
1007                         /*
1008                          * Most if not all the system files in the $Extend
1009                          * system directory do not have unnamed data
1010                          * attributes so we need to check if the parent
1011                          * directory of the file is FILE_Extend and if it is
1012                          * ignore this error. To do this we need to get the
1013                          * name of this inode from the mft record as the name
1014                          * contains the back reference to the parent directory.
1015                          */
1016                         if (ntfs_is_extended_system_file(ctx) > 0)
1017                                 goto no_data_attr_special_case;
1018                         // FIXME: File is corrupt! Hot-fix with empty data
1019                         // attribute if recovery option is set.
1020                         ntfs_error(vi->i_sb, "$DATA attribute is missing.");
1021                         goto unm_err_out;
1022                 }
1023                 a = ctx->attr;
1024                 /* Setup the state. */
1025                 if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1026                         if (a->flags & ATTR_COMPRESSION_MASK) {
1027                                 NInoSetCompressed(ni);
1028                                 if (vol->cluster_size > 4096) {
1029                                         ntfs_error(vi->i_sb, "Found "
1030                                                         "compressed data but "
1031                                                         "compression is "
1032                                                         "disabled due to "
1033                                                         "cluster size (%i) > "
1034                                                         "4kiB.",
1035                                                         vol->cluster_size);
1036                                         goto unm_err_out;
1037                                 }
1038                                 if ((a->flags & ATTR_COMPRESSION_MASK)
1039                                                 != ATTR_IS_COMPRESSED) {
1040                                         ntfs_error(vi->i_sb, "Found unknown "
1041                                                         "compression method "
1042                                                         "or corrupt file.");
1043                                         goto unm_err_out;
1044                                 }
1045                         }
1046                         if (a->flags & ATTR_IS_SPARSE)
1047                                 NInoSetSparse(ni);
1048                 }
1049                 if (a->flags & ATTR_IS_ENCRYPTED) {
1050                         if (NInoCompressed(ni)) {
1051                                 ntfs_error(vi->i_sb, "Found encrypted and "
1052                                                 "compressed data.");
1053                                 goto unm_err_out;
1054                         }
1055                         NInoSetEncrypted(ni);
1056                 }
1057                 if (a->non_resident) {
1058                         NInoSetNonResident(ni);
1059                         if (NInoCompressed(ni) || NInoSparse(ni)) {
1060                                 if (NInoCompressed(ni) && a->data.non_resident.
1061                                                 compression_unit != 4) {
1062                                         ntfs_error(vi->i_sb, "Found "
1063                                                         "non-standard "
1064                                                         "compression unit (%u "
1065                                                         "instead of 4).  "
1066                                                         "Cannot handle this.",
1067                                                         a->data.non_resident.
1068                                                         compression_unit);
1069                                         err = -EOPNOTSUPP;
1070                                         goto unm_err_out;
1071                                 }
1072                                 if (a->data.non_resident.compression_unit) {
1073                                         ni->itype.compressed.block_size = 1U <<
1074                                                         (a->data.non_resident.
1075                                                         compression_unit +
1076                                                         vol->cluster_size_bits);
1077                                         ni->itype.compressed.block_size_bits =
1078                                                         ffs(ni->itype.
1079                                                         compressed.
1080                                                         block_size) - 1;
1081                                         ni->itype.compressed.block_clusters =
1082                                                         1U << a->data.
1083                                                         non_resident.
1084                                                         compression_unit;
1085                                 } else {
1086                                         ni->itype.compressed.block_size = 0;
1087                                         ni->itype.compressed.block_size_bits =
1088                                                         0;
1089                                         ni->itype.compressed.block_clusters =
1090                                                         0;
1091                                 }
1092                                 ni->itype.compressed.size = sle64_to_cpu(
1093                                                 a->data.non_resident.
1094                                                 compressed_size);
1095                         }
1096                         if (a->data.non_resident.lowest_vcn) {
1097                                 ntfs_error(vi->i_sb, "First extent of $DATA "
1098                                                 "attribute has non zero "
1099                                                 "lowest_vcn.");
1100                                 goto unm_err_out;
1101                         }
1102                         vi->i_size = sle64_to_cpu(
1103                                         a->data.non_resident.data_size);
1104                         ni->initialized_size = sle64_to_cpu(
1105                                         a->data.non_resident.initialized_size);
1106                         ni->allocated_size = sle64_to_cpu(
1107                                         a->data.non_resident.allocated_size);
1108                 } else { /* Resident attribute. */
1109                         vi->i_size = ni->initialized_size = le32_to_cpu(
1110                                         a->data.resident.value_length);
1111                         ni->allocated_size = le32_to_cpu(a->length) -
1112                                         le16_to_cpu(
1113                                         a->data.resident.value_offset);
1114                         if (vi->i_size > ni->allocated_size) {
1115                                 ntfs_error(vi->i_sb, "Resident data attribute "
1116                                                 "is corrupt (size exceeds "
1117                                                 "allocation).");
1118                                 goto unm_err_out;
1119                         }
1120                 }
1121 no_data_attr_special_case:
1122                 /* We are done with the mft record, so we release it. */
1123                 ntfs_attr_put_search_ctx(ctx);
1124                 unmap_mft_record(ni);
1125                 m = NULL;
1126                 ctx = NULL;
1127                 /* Setup the operations for this inode. */
1128                 vi->i_op = &ntfs_file_inode_ops;
1129                 vi->i_fop = &ntfs_file_ops;
1130                 vi->i_mapping->a_ops = &ntfs_normal_aops;
1131                 if (NInoMstProtected(ni))
1132                         vi->i_mapping->a_ops = &ntfs_mst_aops;
1133                 else if (NInoCompressed(ni))
1134                         vi->i_mapping->a_ops = &ntfs_compressed_aops;
1135         }
1136         /*
1137          * The number of 512-byte blocks used on disk (for stat). This is in so
1138          * far inaccurate as it doesn't account for any named streams or other
1139          * special non-resident attributes, but that is how Windows works, too,
1140          * so we are at least consistent with Windows, if not entirely
1141          * consistent with the Linux Way. Doing it the Linux Way would cause a
1142          * significant slowdown as it would involve iterating over all
1143          * attributes in the mft record and adding the allocated/compressed
1144          * sizes of all non-resident attributes present to give us the Linux
1145          * correct size that should go into i_blocks (after division by 512).
1146          */
1147         if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
1148                 vi->i_blocks = ni->itype.compressed.size >> 9;
1149         else
1150                 vi->i_blocks = ni->allocated_size >> 9;
1151         ntfs_debug("Done.");
1152         return 0;
1153 iput_unm_err_out:
1154         iput(bvi);
1155 unm_err_out:
1156         if (!err)
1157                 err = -EIO;
1158         if (ctx)
1159                 ntfs_attr_put_search_ctx(ctx);
1160         if (m)
1161                 unmap_mft_record(ni);
1162 err_out:
1163         ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
1164                         "inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
1165         make_bad_inode(vi);
1166         if (err != -EOPNOTSUPP && err != -ENOMEM)
1167                 NVolSetErrors(vol);
1168         return err;
1169 }
1170 
1171 /**
1172  * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
1173  * @base_vi:    base inode
1174  * @vi:         attribute inode to read
1175  *
1176  * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
1177  * attribute inode described by @vi into memory from the base mft record
1178  * described by @base_ni.
1179  *
1180  * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
1181  * reading and looks up the attribute described by @vi before setting up the
1182  * necessary fields in @vi as well as initializing the ntfs inode.
1183  *
1184  * Q: What locks are held when the function is called?
1185  * A: i_state has I_NEW set, hence the inode is locked, also
1186  *    i_count is set to 1, so it is not going to go away
1187  *
1188  * Return 0 on success and -errno on error.  In the error case, the inode will
1189  * have had make_bad_inode() executed on it.
1190  *
1191  * Note this cannot be called for AT_INDEX_ALLOCATION.
1192  */
1193 static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
1194 {
1195         ntfs_volume *vol = NTFS_SB(vi->i_sb);
1196         ntfs_inode *ni, *base_ni;
1197         MFT_RECORD *m;
1198         ATTR_RECORD *a;
1199         ntfs_attr_search_ctx *ctx;
1200         int err = 0;
1201 
1202         ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1203 
1204         ntfs_init_big_inode(vi);
1205 
1206         ni      = NTFS_I(vi);
1207         base_ni = NTFS_I(base_vi);
1208 
1209         /* Just mirror the values from the base inode. */
1210         vi->i_uid       = base_vi->i_uid;
1211         vi->i_gid       = base_vi->i_gid;
1212         set_nlink(vi, base_vi->i_nlink);
1213         vi->i_mtime     = base_vi->i_mtime;
1214         vi->i_ctime     = base_vi->i_ctime;
1215         vi->i_atime     = base_vi->i_atime;
1216         vi->i_generation = ni->seq_no = base_ni->seq_no;
1217 
1218         /* Set inode type to zero but preserve permissions. */
1219         vi->i_mode      = base_vi->i_mode & ~S_IFMT;
1220 
1221         m = map_mft_record(base_ni);
1222         if (IS_ERR(m)) {
1223                 err = PTR_ERR(m);
1224                 goto err_out;
1225         }
1226         ctx = ntfs_attr_get_search_ctx(base_ni, m);
1227         if (!ctx) {
1228                 err = -ENOMEM;
1229                 goto unm_err_out;
1230         }
1231         /* Find the attribute. */
1232         err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1233                         CASE_SENSITIVE, 0, NULL, 0, ctx);
1234         if (unlikely(err))
1235                 goto unm_err_out;
1236         a = ctx->attr;
1237         if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1238                 if (a->flags & ATTR_COMPRESSION_MASK) {
1239                         NInoSetCompressed(ni);
1240                         if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
1241                                         ni->name_len)) {
1242                                 ntfs_error(vi->i_sb, "Found compressed "
1243                                                 "non-data or named data "
1244                                                 "attribute.  Please report "
1245                                                 "you saw this message to "
1246                                                 "linux-ntfs-dev@lists."
1247                                                 "sourceforge.net");
1248                                 goto unm_err_out;
1249                         }
1250                         if (vol->cluster_size > 4096) {
1251                                 ntfs_error(vi->i_sb, "Found compressed "
1252                                                 "attribute but compression is "
1253                                                 "disabled due to cluster size "
1254                                                 "(%i) > 4kiB.",
1255                                                 vol->cluster_size);
1256                                 goto unm_err_out;
1257                         }
1258                         if ((a->flags & ATTR_COMPRESSION_MASK) !=
1259                                         ATTR_IS_COMPRESSED) {
1260                                 ntfs_error(vi->i_sb, "Found unknown "
1261                                                 "compression method.");
1262                                 goto unm_err_out;
1263                         }
1264                 }
1265                 /*
1266                  * The compressed/sparse flag set in an index root just means
1267                  * to compress all files.
1268                  */
1269                 if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1270                         ntfs_error(vi->i_sb, "Found mst protected attribute "
1271                                         "but the attribute is %s.  Please "
1272                                         "report you saw this message to "
1273                                         "linux-ntfs-dev@lists.sourceforge.net",
1274                                         NInoCompressed(ni) ? "compressed" :
1275                                         "sparse");
1276                         goto unm_err_out;
1277                 }
1278                 if (a->flags & ATTR_IS_SPARSE)
1279                         NInoSetSparse(ni);
1280         }
1281         if (a->flags & ATTR_IS_ENCRYPTED) {
1282                 if (NInoCompressed(ni)) {
1283                         ntfs_error(vi->i_sb, "Found encrypted and compressed "
1284                                         "data.");
1285                         goto unm_err_out;
1286                 }
1287                 /*
1288                  * The encryption flag set in an index root just means to
1289                  * encrypt all files.
1290                  */
1291                 if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1292                         ntfs_error(vi->i_sb, "Found mst protected attribute "
1293                                         "but the attribute is encrypted.  "
1294                                         "Please report you saw this message "
1295                                         "to linux-ntfs-dev@lists.sourceforge."
1296                                         "net");
1297                         goto unm_err_out;
1298                 }
1299                 if (ni->type != AT_DATA) {
1300                         ntfs_error(vi->i_sb, "Found encrypted non-data "
1301                                         "attribute.");
1302                         goto unm_err_out;
1303                 }
1304                 NInoSetEncrypted(ni);
1305         }
1306         if (!a->non_resident) {
1307                 /* Ensure the attribute name is placed before the value. */
1308                 if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1309                                 le16_to_cpu(a->data.resident.value_offset)))) {
1310                         ntfs_error(vol->sb, "Attribute name is placed after "
1311                                         "the attribute value.");
1312                         goto unm_err_out;
1313                 }
1314                 if (NInoMstProtected(ni)) {
1315                         ntfs_error(vi->i_sb, "Found mst protected attribute "
1316                                         "but the attribute is resident.  "
1317                                         "Please report you saw this message to "
1318                                         "linux-ntfs-dev@lists.sourceforge.net");
1319                         goto unm_err_out;
1320                 }
1321                 vi->i_size = ni->initialized_size = le32_to_cpu(
1322                                 a->data.resident.value_length);
1323                 ni->allocated_size = le32_to_cpu(a->length) -
1324                                 le16_to_cpu(a->data.resident.value_offset);
1325                 if (vi->i_size > ni->allocated_size) {
1326                         ntfs_error(vi->i_sb, "Resident attribute is corrupt "
1327                                         "(size exceeds allocation).");
1328                         goto unm_err_out;
1329                 }
1330         } else {
1331                 NInoSetNonResident(ni);
1332                 /*
1333                  * Ensure the attribute name is placed before the mapping pairs
1334                  * array.
1335                  */
1336                 if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1337                                 le16_to_cpu(
1338                                 a->data.non_resident.mapping_pairs_offset)))) {
1339                         ntfs_error(vol->sb, "Attribute name is placed after "
1340                                         "the mapping pairs array.");
1341                         goto unm_err_out;
1342                 }
1343                 if (NInoCompressed(ni) || NInoSparse(ni)) {
1344                         if (NInoCompressed(ni) && a->data.non_resident.
1345                                         compression_unit != 4) {
1346                                 ntfs_error(vi->i_sb, "Found non-standard "
1347                                                 "compression unit (%u instead "
1348                                                 "of 4).  Cannot handle this.",
1349                                                 a->data.non_resident.
1350                                                 compression_unit);
1351                                 err = -EOPNOTSUPP;
1352                                 goto unm_err_out;
1353                         }
1354                         if (a->data.non_resident.compression_unit) {
1355                                 ni->itype.compressed.block_size = 1U <<
1356                                                 (a->data.non_resident.
1357                                                 compression_unit +
1358                                                 vol->cluster_size_bits);
1359                                 ni->itype.compressed.block_size_bits =
1360                                                 ffs(ni->itype.compressed.
1361                                                 block_size) - 1;
1362                                 ni->itype.compressed.block_clusters = 1U <<
1363                                                 a->data.non_resident.
1364                                                 compression_unit;
1365                         } else {
1366                                 ni->itype.compressed.block_size = 0;
1367                                 ni->itype.compressed.block_size_bits = 0;
1368                                 ni->itype.compressed.block_clusters = 0;
1369                         }
1370                         ni->itype.compressed.size = sle64_to_cpu(
1371                                         a->data.non_resident.compressed_size);
1372                 }
1373                 if (a->data.non_resident.lowest_vcn) {
1374                         ntfs_error(vi->i_sb, "First extent of attribute has "
1375                                         "non-zero lowest_vcn.");
1376                         goto unm_err_out;
1377                 }
1378                 vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1379                 ni->initialized_size = sle64_to_cpu(
1380                                 a->data.non_resident.initialized_size);
1381                 ni->allocated_size = sle64_to_cpu(
1382                                 a->data.non_resident.allocated_size);
1383         }
1384         vi->i_mapping->a_ops = &ntfs_normal_aops;
1385         if (NInoMstProtected(ni))
1386                 vi->i_mapping->a_ops = &ntfs_mst_aops;
1387         else if (NInoCompressed(ni))
1388                 vi->i_mapping->a_ops = &ntfs_compressed_aops;
1389         if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
1390                 vi->i_blocks = ni->itype.compressed.size >> 9;
1391         else
1392                 vi->i_blocks = ni->allocated_size >> 9;
1393         /*
1394          * Make sure the base inode does not go away and attach it to the
1395          * attribute inode.
1396          */
1397         igrab(base_vi);
1398         ni->ext.base_ntfs_ino = base_ni;
1399         ni->nr_extents = -1;
1400 
1401         ntfs_attr_put_search_ctx(ctx);
1402         unmap_mft_record(base_ni);
1403 
1404         ntfs_debug("Done.");
1405         return 0;
1406 
1407 unm_err_out:
1408         if (!err)
1409                 err = -EIO;
1410         if (ctx)
1411                 ntfs_attr_put_search_ctx(ctx);
1412         unmap_mft_record(base_ni);
1413 err_out:
1414         ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
1415                         "inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
1416                         "Marking corrupt inode and base inode 0x%lx as bad.  "
1417                         "Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
1418                         base_vi->i_ino);
1419         make_bad_inode(vi);
1420         if (err != -ENOMEM)
1421                 NVolSetErrors(vol);
1422         return err;
1423 }
1424 
1425 /**
1426  * ntfs_read_locked_index_inode - read an index inode from its base inode
1427  * @base_vi:    base inode
1428  * @vi:         index inode to read
1429  *
1430  * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
1431  * index inode described by @vi into memory from the base mft record described
1432  * by @base_ni.
1433  *
1434  * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
1435  * reading and looks up the attributes relating to the index described by @vi
1436  * before setting up the necessary fields in @vi as well as initializing the
1437  * ntfs inode.
1438  *
1439  * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
1440  * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
1441  * are setup like directory inodes since directories are a special case of
1442  * indices ao they need to be treated in much the same way.  Most importantly,
1443  * for small indices the index allocation attribute might not actually exist.
1444  * However, the index root attribute always exists but this does not need to
1445  * have an inode associated with it and this is why we define a new inode type
1446  * index.  Also, like for directories, we need to have an attribute inode for
1447  * the bitmap attribute corresponding to the index allocation attribute and we
1448  * can store this in the appropriate field of the inode, just like we do for
1449  * normal directory inodes.
1450  *
1451  * Q: What locks are held when the function is called?
1452  * A: i_state has I_NEW set, hence the inode is locked, also
1453  *    i_count is set to 1, so it is not going to go away
1454  *
1455  * Return 0 on success and -errno on error.  In the error case, the inode will
1456  * have had make_bad_inode() executed on it.
1457  */
1458 static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
1459 {
1460         loff_t bvi_size;
1461         ntfs_volume *vol = NTFS_SB(vi->i_sb);
1462         ntfs_inode *ni, *base_ni, *bni;
1463         struct inode *bvi;
1464         MFT_RECORD *m;
1465         ATTR_RECORD *a;
1466         ntfs_attr_search_ctx *ctx;
1467         INDEX_ROOT *ir;
1468         u8 *ir_end, *index_end;
1469         int err = 0;
1470 
1471         ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1472         ntfs_init_big_inode(vi);
1473         ni      = NTFS_I(vi);
1474         base_ni = NTFS_I(base_vi);
1475         /* Just mirror the values from the base inode. */
1476         vi->i_uid       = base_vi->i_uid;
1477         vi->i_gid       = base_vi->i_gid;
1478         set_nlink(vi, base_vi->i_nlink);
1479         vi->i_mtime     = base_vi->i_mtime;
1480         vi->i_ctime     = base_vi->i_ctime;
1481         vi->i_atime     = base_vi->i_atime;
1482         vi->i_generation = ni->seq_no = base_ni->seq_no;
1483         /* Set inode type to zero but preserve permissions. */
1484         vi->i_mode      = base_vi->i_mode & ~S_IFMT;
1485         /* Map the mft record for the base inode. */
1486         m = map_mft_record(base_ni);
1487         if (IS_ERR(m)) {
1488                 err = PTR_ERR(m);
1489                 goto err_out;
1490         }
1491         ctx = ntfs_attr_get_search_ctx(base_ni, m);
1492         if (!ctx) {
1493                 err = -ENOMEM;
1494                 goto unm_err_out;
1495         }
1496         /* Find the index root attribute. */
1497         err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
1498                         CASE_SENSITIVE, 0, NULL, 0, ctx);
1499         if (unlikely(err)) {
1500                 if (err == -ENOENT)
1501                         ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
1502                                         "missing.");
1503                 goto unm_err_out;
1504         }
1505         a = ctx->attr;
1506         /* Set up the state. */
1507         if (unlikely(a->non_resident)) {
1508                 ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
1509                 goto unm_err_out;
1510         }
1511         /* Ensure the attribute name is placed before the value. */
1512         if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1513                         le16_to_cpu(a->data.resident.value_offset)))) {
1514                 ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
1515                                 "after the attribute value.");
1516                 goto unm_err_out;
1517         }
1518         /*
1519          * Compressed/encrypted/sparse index root is not allowed, except for
1520          * directories of course but those are not dealt with here.
1521          */
1522         if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
1523                         ATTR_IS_SPARSE)) {
1524                 ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
1525                                 "root attribute.");
1526                 goto unm_err_out;
1527         }
1528         ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
1529         ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
1530         if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
1531                 ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
1532                 goto unm_err_out;
1533         }
1534         index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
1535         if (index_end > ir_end) {
1536                 ntfs_error(vi->i_sb, "Index is corrupt.");
1537                 goto unm_err_out;
1538         }
1539         if (ir->type) {
1540                 ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
1541                                 le32_to_cpu(ir->type));
1542                 goto unm_err_out;
1543         }
1544         ni->itype.index.collation_rule = ir->collation_rule;
1545         ntfs_debug("Index collation rule is 0x%x.",
1546                         le32_to_cpu(ir->collation_rule));
1547         ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
1548         if (!is_power_of_2(ni->itype.index.block_size)) {
1549                 ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
1550                                 "two.", ni->itype.index.block_size);
1551                 goto unm_err_out;
1552         }
1553         if (ni->itype.index.block_size > PAGE_SIZE) {
1554                 ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_SIZE "
1555                                 "(%ld) is not supported.  Sorry.",
1556                                 ni->itype.index.block_size, PAGE_SIZE);
1557                 err = -EOPNOTSUPP;
1558                 goto unm_err_out;
1559         }
1560         if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
1561                 ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
1562                                 "(%i) is not supported.  Sorry.",
1563                                 ni->itype.index.block_size, NTFS_BLOCK_SIZE);
1564                 err = -EOPNOTSUPP;
1565                 goto unm_err_out;
1566         }
1567         ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
1568         /* Determine the size of a vcn in the index. */
1569         if (vol->cluster_size <= ni->itype.index.block_size) {
1570                 ni->itype.index.vcn_size = vol->cluster_size;
1571                 ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
1572         } else {
1573                 ni->itype.index.vcn_size = vol->sector_size;
1574                 ni->itype.index.vcn_size_bits = vol->sector_size_bits;
1575         }
1576         /* Check for presence of index allocation attribute. */
1577         if (!(ir->index.flags & LARGE_INDEX)) {
1578                 /* No index allocation. */
1579                 vi->i_size = ni->initialized_size = ni->allocated_size = 0;
1580                 /* We are done with the mft record, so we release it. */
1581                 ntfs_attr_put_search_ctx(ctx);
1582                 unmap_mft_record(base_ni);
1583                 m = NULL;
1584                 ctx = NULL;
1585                 goto skip_large_index_stuff;
1586         } /* LARGE_INDEX:  Index allocation present.  Setup state. */
1587         NInoSetIndexAllocPresent(ni);
1588         /* Find index allocation attribute. */
1589         ntfs_attr_reinit_search_ctx(ctx);
1590         err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
1591                         CASE_SENSITIVE, 0, NULL, 0, ctx);
1592         if (unlikely(err)) {
1593                 if (err == -ENOENT)
1594                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1595                                         "not present but $INDEX_ROOT "
1596                                         "indicated it is.");
1597                 else
1598                         ntfs_error(vi->i_sb, "Failed to lookup "
1599                                         "$INDEX_ALLOCATION attribute.");
1600                 goto unm_err_out;
1601         }
1602         a = ctx->attr;
1603         if (!a->non_resident) {
1604                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1605                                 "resident.");
1606                 goto unm_err_out;
1607         }
1608         /*
1609          * Ensure the attribute name is placed before the mapping pairs array.
1610          */
1611         if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1612                         le16_to_cpu(
1613                         a->data.non_resident.mapping_pairs_offset)))) {
1614                 ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
1615                                 "placed after the mapping pairs array.");
1616                 goto unm_err_out;
1617         }
1618         if (a->flags & ATTR_IS_ENCRYPTED) {
1619                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1620                                 "encrypted.");
1621                 goto unm_err_out;
1622         }
1623         if (a->flags & ATTR_IS_SPARSE) {
1624                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
1625                 goto unm_err_out;
1626         }
1627         if (a->flags & ATTR_COMPRESSION_MASK) {
1628                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1629                                 "compressed.");
1630                 goto unm_err_out;
1631         }
1632         if (a->data.non_resident.lowest_vcn) {
1633                 ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
1634                                 "attribute has non zero lowest_vcn.");
1635                 goto unm_err_out;
1636         }
1637         vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1638         ni->initialized_size = sle64_to_cpu(
1639                         a->data.non_resident.initialized_size);
1640         ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
1641         /*
1642          * We are done with the mft record, so we release it.  Otherwise
1643          * we would deadlock in ntfs_attr_iget().
1644          */
1645         ntfs_attr_put_search_ctx(ctx);
1646         unmap_mft_record(base_ni);
1647         m = NULL;
1648         ctx = NULL;
1649         /* Get the index bitmap attribute inode. */
1650         bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
1651         if (IS_ERR(bvi)) {
1652                 ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
1653                 err = PTR_ERR(bvi);
1654                 goto unm_err_out;
1655         }
1656         bni = NTFS_I(bvi);
1657         if (NInoCompressed(bni) || NInoEncrypted(bni) ||
1658                         NInoSparse(bni)) {
1659                 ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
1660                                 "encrypted and/or sparse.");
1661                 goto iput_unm_err_out;
1662         }
1663         /* Consistency check bitmap size vs. index allocation size. */
1664         bvi_size = i_size_read(bvi);
1665         if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
1666                 ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
1667                                 "index allocation (0x%llx).", bvi_size << 3,
1668                                 vi->i_size);
1669                 goto iput_unm_err_out;
1670         }
1671         iput(bvi);
1672 skip_large_index_stuff:
1673         /* Setup the operations for this index inode. */
1674         vi->i_mapping->a_ops = &ntfs_mst_aops;
1675         vi->i_blocks = ni->allocated_size >> 9;
1676         /*
1677          * Make sure the base inode doesn't go away and attach it to the
1678          * index inode.
1679          */
1680         igrab(base_vi);
1681         ni->ext.base_ntfs_ino = base_ni;
1682         ni->nr_extents = -1;
1683 
1684         ntfs_debug("Done.");
1685         return 0;
1686 iput_unm_err_out:
1687         iput(bvi);
1688 unm_err_out:
1689         if (!err)
1690                 err = -EIO;
1691         if (ctx)
1692                 ntfs_attr_put_search_ctx(ctx);
1693         if (m)
1694                 unmap_mft_record(base_ni);
1695 err_out:
1696         ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
1697                         "inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
1698                         ni->name_len);
1699         make_bad_inode(vi);
1700         if (err != -EOPNOTSUPP && err != -ENOMEM)
1701                 NVolSetErrors(vol);
1702         return err;
1703 }
1704 
1705 /*
1706  * The MFT inode has special locking, so teach the lock validator
1707  * about this by splitting off the locking rules of the MFT from
1708  * the locking rules of other inodes. The MFT inode can never be
1709  * accessed from the VFS side (or even internally), only by the
1710  * map_mft functions.
1711  */
1712 static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;
1713 
1714 /**
1715  * ntfs_read_inode_mount - special read_inode for mount time use only
1716  * @vi:         inode to read
1717  *
1718  * Read inode FILE_MFT at mount time, only called with super_block lock
1719  * held from within the read_super() code path.
1720  *
1721  * This function exists because when it is called the page cache for $MFT/$DATA
1722  * is not initialized and hence we cannot get at the contents of mft records
1723  * by calling map_mft_record*().
1724  *
1725  * Further it needs to cope with the circular references problem, i.e. cannot
1726  * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
1727  * we do not know where the other extent mft records are yet and again, because
1728  * we cannot call map_mft_record*() yet.  Obviously this applies only when an
1729  * attribute list is actually present in $MFT inode.
1730  *
1731  * We solve these problems by starting with the $DATA attribute before anything
1732  * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
1733  * extent is found, we ntfs_mapping_pairs_decompress() including the implied
1734  * ntfs_runlists_merge().  Each step of the iteration necessarily provides
1735  * sufficient information for the next step to complete.
1736  *
1737  * This should work but there are two possible pit falls (see inline comments
1738  * below), but only time will tell if they are real pits or just smoke...
1739  */
1740 int ntfs_read_inode_mount(struct inode *vi)
1741 {
1742         VCN next_vcn, last_vcn, highest_vcn;
1743         s64 block;
1744         struct super_block *sb = vi->i_sb;
1745         ntfs_volume *vol = NTFS_SB(sb);
1746         struct buffer_head *bh;
1747         ntfs_inode *ni;
1748         MFT_RECORD *m = NULL;
1749         ATTR_RECORD *a;
1750         ntfs_attr_search_ctx *ctx;
1751         unsigned int i, nr_blocks;
1752         int err;
1753 
1754         ntfs_debug("Entering.");
1755 
1756         /* Initialize the ntfs specific part of @vi. */
1757         ntfs_init_big_inode(vi);
1758 
1759         ni = NTFS_I(vi);
1760 
1761         /* Setup the data attribute. It is special as it is mst protected. */
1762         NInoSetNonResident(ni);
1763         NInoSetMstProtected(ni);
1764         NInoSetSparseDisabled(ni);
1765         ni->type = AT_DATA;
1766         ni->name = NULL;
1767         ni->name_len = 0;
1768         /*
1769          * This sets up our little cheat allowing us to reuse the async read io
1770          * completion handler for directories.
1771          */
1772         ni->itype.index.block_size = vol->mft_record_size;
1773         ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1774 
1775         /* Very important! Needed to be able to call map_mft_record*(). */
1776         vol->mft_ino = vi;
1777 
1778         /* Allocate enough memory to read the first mft record. */
1779         if (vol->mft_record_size > 64 * 1024) {
1780                 ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
1781                                 vol->mft_record_size);
1782                 goto err_out;
1783         }
1784         i = vol->mft_record_size;
1785         if (i < sb->s_blocksize)
1786                 i = sb->s_blocksize;
1787         m = (MFT_RECORD*)ntfs_malloc_nofs(i);
1788         if (!m) {
1789                 ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
1790                 goto err_out;
1791         }
1792 
1793         /* Determine the first block of the $MFT/$DATA attribute. */
1794         block = vol->mft_lcn << vol->cluster_size_bits >>
1795                         sb->s_blocksize_bits;
1796         nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
1797         if (!nr_blocks)
1798                 nr_blocks = 1;
1799 
1800         /* Load $MFT/$DATA's first mft record. */
1801         for (i = 0; i < nr_blocks; i++) {
1802                 bh = sb_bread(sb, block++);
1803                 if (!bh) {
1804                         ntfs_error(sb, "Device read failed.");
1805                         goto err_out;
1806                 }
1807                 memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
1808                                 sb->s_blocksize);
1809                 brelse(bh);
1810         }
1811 
1812         /* Apply the mst fixups. */
1813         if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
1814                 /* FIXME: Try to use the $MFTMirr now. */
1815                 ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
1816                 goto err_out;
1817         }
1818 
1819         /* Need this to sanity check attribute list references to $MFT. */
1820         vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
1821 
1822         /* Provides readpage() for map_mft_record(). */
1823         vi->i_mapping->a_ops = &ntfs_mst_aops;
1824 
1825         ctx = ntfs_attr_get_search_ctx(ni, m);
1826         if (!ctx) {
1827                 err = -ENOMEM;
1828                 goto err_out;
1829         }
1830 
1831         /* Find the attribute list attribute if present. */
1832         err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
1833         if (err) {
1834                 if (unlikely(err != -ENOENT)) {
1835                         ntfs_error(sb, "Failed to lookup attribute list "
1836                                         "attribute. You should run chkdsk.");
1837                         goto put_err_out;
1838                 }
1839         } else /* if (!err) */ {
1840                 ATTR_LIST_ENTRY *al_entry, *next_al_entry;
1841                 u8 *al_end;
1842                 static const char *es = "  Not allowed.  $MFT is corrupt.  "
1843                                 "You should run chkdsk.";
1844 
1845                 ntfs_debug("Attribute list attribute found in $MFT.");
1846                 NInoSetAttrList(ni);
1847                 a = ctx->attr;
1848                 if (a->flags & ATTR_COMPRESSION_MASK) {
1849                         ntfs_error(sb, "Attribute list attribute is "
1850                                         "compressed.%s", es);
1851                         goto put_err_out;
1852                 }
1853                 if (a->flags & ATTR_IS_ENCRYPTED ||
1854                                 a->flags & ATTR_IS_SPARSE) {
1855                         if (a->non_resident) {
1856                                 ntfs_error(sb, "Non-resident attribute list "
1857                                                 "attribute is encrypted/"
1858                                                 "sparse.%s", es);
1859                                 goto put_err_out;
1860                         }
1861                         ntfs_warning(sb, "Resident attribute list attribute "
1862                                         "in $MFT system file is marked "
1863                                         "encrypted/sparse which is not true.  "
1864                                         "However, Windows allows this and "
1865                                         "chkdsk does not detect or correct it "
1866                                         "so we will just ignore the invalid "
1867                                         "flags and pretend they are not set.");
1868                 }
1869                 /* Now allocate memory for the attribute list. */
1870                 ni->attr_list_size = (u32)ntfs_attr_size(a);
1871                 ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
1872                 if (!ni->attr_list) {
1873                         ntfs_error(sb, "Not enough memory to allocate buffer "
1874                                         "for attribute list.");
1875                         goto put_err_out;
1876                 }
1877                 if (a->non_resident) {
1878                         NInoSetAttrListNonResident(ni);
1879                         if (a->data.non_resident.lowest_vcn) {
1880                                 ntfs_error(sb, "Attribute list has non zero "
1881                                                 "lowest_vcn. $MFT is corrupt. "
1882                                                 "You should run chkdsk.");
1883                                 goto put_err_out;
1884                         }
1885                         /* Setup the runlist. */
1886                         ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
1887                                         a, NULL);
1888                         if (IS_ERR(ni->attr_list_rl.rl)) {
1889                                 err = PTR_ERR(ni->attr_list_rl.rl);
1890                                 ni->attr_list_rl.rl = NULL;
1891                                 ntfs_error(sb, "Mapping pairs decompression "
1892                                                 "failed with error code %i.",
1893                                                 -err);
1894                                 goto put_err_out;
1895                         }
1896                         /* Now load the attribute list. */
1897                         if ((err = load_attribute_list(vol, &ni->attr_list_rl,
1898                                         ni->attr_list, ni->attr_list_size,
1899                                         sle64_to_cpu(a->data.
1900                                         non_resident.initialized_size)))) {
1901                                 ntfs_error(sb, "Failed to load attribute list "
1902                                                 "attribute with error code %i.",
1903                                                 -err);
1904                                 goto put_err_out;
1905                         }
1906                 } else /* if (!ctx.attr->non_resident) */ {
1907                         if ((u8*)a + le16_to_cpu(
1908                                         a->data.resident.value_offset) +
1909                                         le32_to_cpu(
1910                                         a->data.resident.value_length) >
1911                                         (u8*)ctx->mrec + vol->mft_record_size) {
1912                                 ntfs_error(sb, "Corrupt attribute list "
1913                                                 "attribute.");
1914                                 goto put_err_out;
1915                         }
1916                         /* Now copy the attribute list. */
1917                         memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
1918                                         a->data.resident.value_offset),
1919                                         le32_to_cpu(
1920                                         a->data.resident.value_length));
1921                 }
1922                 /* The attribute list is now setup in memory. */
1923                 /*
1924                  * FIXME: I don't know if this case is actually possible.
1925                  * According to logic it is not possible but I have seen too
1926                  * many weird things in MS software to rely on logic... Thus we
1927                  * perform a manual search and make sure the first $MFT/$DATA
1928                  * extent is in the base inode. If it is not we abort with an
1929                  * error and if we ever see a report of this error we will need
1930                  * to do some magic in order to have the necessary mft record
1931                  * loaded and in the right place in the page cache. But
1932                  * hopefully logic will prevail and this never happens...
1933                  */
1934                 al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
1935                 al_end = (u8*)al_entry + ni->attr_list_size;
1936                 for (;; al_entry = next_al_entry) {
1937                         /* Out of bounds check. */
1938                         if ((u8*)al_entry < ni->attr_list ||
1939                                         (u8*)al_entry > al_end)
1940                                 goto em_put_err_out;
1941                         /* Catch the end of the attribute list. */
1942                         if ((u8*)al_entry == al_end)
1943                                 goto em_put_err_out;
1944                         if (!al_entry->length)
1945                                 goto em_put_err_out;
1946                         if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
1947                                         le16_to_cpu(al_entry->length) > al_end)
1948                                 goto em_put_err_out;
1949                         next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
1950                                         le16_to_cpu(al_entry->length));
1951                         if (le32_to_cpu(al_entry->type) > le32_to_cpu(AT_DATA))
1952                                 goto em_put_err_out;
1953                         if (AT_DATA != al_entry->type)
1954                                 continue;
1955                         /* We want an unnamed attribute. */
1956                         if (al_entry->name_length)
1957                                 goto em_put_err_out;
1958                         /* Want the first entry, i.e. lowest_vcn == 0. */
1959                         if (al_entry->lowest_vcn)
1960                                 goto em_put_err_out;
1961                         /* First entry has to be in the base mft record. */
1962                         if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
1963                                 /* MFT references do not match, logic fails. */
1964                                 ntfs_error(sb, "BUG: The first $DATA extent "
1965                                                 "of $MFT is not in the base "
1966                                                 "mft record. Please report "
1967                                                 "you saw this message to "
1968                                                 "linux-ntfs-dev@lists."
1969                                                 "sourceforge.net");
1970                                 goto put_err_out;
1971                         } else {
1972                                 /* Sequence numbers must match. */
1973                                 if (MSEQNO_LE(al_entry->mft_reference) !=
1974                                                 ni->seq_no)
1975                                         goto em_put_err_out;
1976                                 /* Got it. All is ok. We can stop now. */
1977                                 break;
1978                         }
1979                 }
1980         }
1981 
1982         ntfs_attr_reinit_search_ctx(ctx);
1983 
1984         /* Now load all attribute extents. */
1985         a = NULL;
1986         next_vcn = last_vcn = highest_vcn = 0;
1987         while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
1988                         ctx))) {
1989                 runlist_element *nrl;
1990 
1991                 /* Cache the current attribute. */
1992                 a = ctx->attr;
1993                 /* $MFT must be non-resident. */
1994                 if (!a->non_resident) {
1995                         ntfs_error(sb, "$MFT must be non-resident but a "
1996                                         "resident extent was found. $MFT is "
1997                                         "corrupt. Run chkdsk.");
1998                         goto put_err_out;
1999                 }
2000                 /* $MFT must be uncompressed and unencrypted. */
2001                 if (a->flags & ATTR_COMPRESSION_MASK ||
2002                                 a->flags & ATTR_IS_ENCRYPTED ||
2003                                 a->flags & ATTR_IS_SPARSE) {
2004                         ntfs_error(sb, "$MFT must be uncompressed, "
2005                                         "non-sparse, and unencrypted but a "
2006                                         "compressed/sparse/encrypted extent "
2007                                         "was found. $MFT is corrupt. Run "
2008                                         "chkdsk.");
2009                         goto put_err_out;
2010                 }
2011                 /*
2012                  * Decompress the mapping pairs array of this extent and merge
2013                  * the result into the existing runlist. No need for locking
2014                  * as we have exclusive access to the inode at this time and we
2015                  * are a mount in progress task, too.
2016                  */
2017                 nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2018                 if (IS_ERR(nrl)) {
2019                         ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
2020                                         "failed with error code %ld.  $MFT is "
2021                                         "corrupt.", PTR_ERR(nrl));
2022                         goto put_err_out;
2023                 }
2024                 ni->runlist.rl = nrl;
2025 
2026                 /* Are we in the first extent? */
2027                 if (!next_vcn) {
2028                         if (a->data.non_resident.lowest_vcn) {
2029                                 ntfs_error(sb, "First extent of $DATA "
2030                                                 "attribute has non zero "
2031                                                 "lowest_vcn. $MFT is corrupt. "
2032                                                 "You should run chkdsk.");
2033                                 goto put_err_out;
2034                         }
2035                         /* Get the last vcn in the $DATA attribute. */
2036                         last_vcn = sle64_to_cpu(
2037                                         a->data.non_resident.allocated_size)
2038                                         >> vol->cluster_size_bits;
2039                         /* Fill in the inode size. */
2040                         vi->i_size = sle64_to_cpu(
2041                                         a->data.non_resident.data_size);
2042                         ni->initialized_size = sle64_to_cpu(
2043                                         a->data.non_resident.initialized_size);
2044                         ni->allocated_size = sle64_to_cpu(
2045                                         a->data.non_resident.allocated_size);
2046                         /*
2047                          * Verify the number of mft records does not exceed
2048                          * 2^32 - 1.
2049                          */
2050                         if ((vi->i_size >> vol->mft_record_size_bits) >=
2051                                         (1ULL << 32)) {
2052                                 ntfs_error(sb, "$MFT is too big! Aborting.");
2053                                 goto put_err_out;
2054                         }
2055                         /*
2056                          * We have got the first extent of the runlist for
2057                          * $MFT which means it is now relatively safe to call
2058                          * the normal ntfs_read_inode() function.
2059                          * Complete reading the inode, this will actually
2060                          * re-read the mft record for $MFT, this time entering
2061                          * it into the page cache with which we complete the
2062                          * kick start of the volume. It should be safe to do
2063                          * this now as the first extent of $MFT/$DATA is
2064                          * already known and we would hope that we don't need
2065                          * further extents in order to find the other
2066                          * attributes belonging to $MFT. Only time will tell if
2067                          * this is really the case. If not we will have to play
2068                          * magic at this point, possibly duplicating a lot of
2069                          * ntfs_read_inode() at this point. We will need to
2070                          * ensure we do enough of its work to be able to call
2071                          * ntfs_read_inode() on extents of $MFT/$DATA. But lets
2072                          * hope this never happens...
2073                          */
2074                         ntfs_read_locked_inode(vi);
2075                         if (is_bad_inode(vi)) {
2076                                 ntfs_error(sb, "ntfs_read_inode() of $MFT "
2077                                                 "failed. BUG or corrupt $MFT. "
2078                                                 "Run chkdsk and if no errors "
2079                                                 "are found, please report you "
2080                                                 "saw this message to "
2081                                                 "linux-ntfs-dev@lists."
2082                                                 "sourceforge.net");
2083                                 ntfs_attr_put_search_ctx(ctx);
2084                                 /* Revert to the safe super operations. */
2085                                 ntfs_free(m);
2086                                 return -1;
2087                         }
2088                         /*
2089                          * Re-initialize some specifics about $MFT's inode as
2090                          * ntfs_read_inode() will have set up the default ones.
2091                          */
2092                         /* Set uid and gid to root. */
2093                         vi->i_uid = GLOBAL_ROOT_UID;
2094                         vi->i_gid = GLOBAL_ROOT_GID;
2095                         /* Regular file. No access for anyone. */
2096                         vi->i_mode = S_IFREG;
2097                         /* No VFS initiated operations allowed for $MFT. */
2098                         vi->i_op = &ntfs_empty_inode_ops;
2099                         vi->i_fop = &ntfs_empty_file_ops;
2100                 }
2101 
2102                 /* Get the lowest vcn for the next extent. */
2103                 highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2104                 next_vcn = highest_vcn + 1;
2105 
2106                 /* Only one extent or error, which we catch below. */
2107                 if (next_vcn <= 0)
2108                         break;
2109 
2110                 /* Avoid endless loops due to corruption. */
2111                 if (next_vcn < sle64_to_cpu(
2112                                 a->data.non_resident.lowest_vcn)) {
2113                         ntfs_error(sb, "$MFT has corrupt attribute list "
2114                                         "attribute. Run chkdsk.");
2115                         goto put_err_out;
2116                 }
2117         }
2118         if (err != -ENOENT) {
2119                 ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
2120                                 "$MFT is corrupt. Run chkdsk.");
2121                 goto put_err_out;
2122         }
2123         if (!a) {
2124                 ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
2125                                 "corrupt. Run chkdsk.");
2126                 goto put_err_out;
2127         }
2128         if (highest_vcn && highest_vcn != last_vcn - 1) {
2129                 ntfs_error(sb, "Failed to load the complete runlist for "
2130                                 "$MFT/$DATA. Driver bug or corrupt $MFT. "
2131                                 "Run chkdsk.");
2132                 ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
2133                                 (unsigned long long)highest_vcn,
2134                                 (unsigned long long)last_vcn - 1);
2135                 goto put_err_out;
2136         }
2137         ntfs_attr_put_search_ctx(ctx);
2138         ntfs_debug("Done.");
2139         ntfs_free(m);
2140 
2141         /*
2142          * Split the locking rules of the MFT inode from the
2143          * locking rules of other inodes:
2144          */
2145         lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
2146         lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);
2147 
2148         return 0;
2149 
2150 em_put_err_out:
2151         ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
2152                         "attribute list. $MFT is corrupt. Run chkdsk.");
2153 put_err_out:
2154         ntfs_attr_put_search_ctx(ctx);
2155 err_out:
2156         ntfs_error(sb, "Failed. Marking inode as bad.");
2157         make_bad_inode(vi);
2158         ntfs_free(m);
2159         return -1;
2160 }
2161 
2162 static void __ntfs_clear_inode(ntfs_inode *ni)
2163 {
2164         /* Free all alocated memory. */
2165         down_write(&ni->runlist.lock);
2166         if (ni->runlist.rl) {
2167                 ntfs_free(ni->runlist.rl);
2168                 ni->runlist.rl = NULL;
2169         }
2170         up_write(&ni->runlist.lock);
2171 
2172         if (ni->attr_list) {
2173                 ntfs_free(ni->attr_list);
2174                 ni->attr_list = NULL;
2175         }
2176 
2177         down_write(&ni->attr_list_rl.lock);
2178         if (ni->attr_list_rl.rl) {
2179                 ntfs_free(ni->attr_list_rl.rl);
2180                 ni->attr_list_rl.rl = NULL;
2181         }
2182         up_write(&ni->attr_list_rl.lock);
2183 
2184         if (ni->name_len && ni->name != I30) {
2185                 /* Catch bugs... */
2186                 BUG_ON(!ni->name);
2187                 kfree(ni->name);
2188         }
2189 }
2190 
2191 void ntfs_clear_extent_inode(ntfs_inode *ni)
2192 {
2193         ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
2194 
2195         BUG_ON(NInoAttr(ni));
2196         BUG_ON(ni->nr_extents != -1);
2197 
2198 #ifdef NTFS_RW
2199         if (NInoDirty(ni)) {
2200                 if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
2201                         ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
2202                                         "Losing data!  This is a BUG!!!");
2203                 // FIXME:  Do something!!!
2204         }
2205 #endif /* NTFS_RW */
2206 
2207         __ntfs_clear_inode(ni);
2208 
2209         /* Bye, bye... */
2210         ntfs_destroy_extent_inode(ni);
2211 }
2212 
2213 /**
2214  * ntfs_evict_big_inode - clean up the ntfs specific part of an inode
2215  * @vi:         vfs inode pending annihilation
2216  *
2217  * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
2218  * is called, which deallocates all memory belonging to the NTFS specific part
2219  * of the inode and returns.
2220  *
2221  * If the MFT record is dirty, we commit it before doing anything else.
2222  */
2223 void ntfs_evict_big_inode(struct inode *vi)
2224 {
2225         ntfs_inode *ni = NTFS_I(vi);
2226 
2227         truncate_inode_pages_final(&vi->i_data);
2228         clear_inode(vi);
2229 
2230 #ifdef NTFS_RW
2231         if (NInoDirty(ni)) {
2232                 bool was_bad = (is_bad_inode(vi));
2233 
2234                 /* Committing the inode also commits all extent inodes. */
2235                 ntfs_commit_inode(vi);
2236 
2237                 if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
2238                         ntfs_error(vi->i_sb, "Failed to commit dirty inode "
2239                                         "0x%lx.  Losing data!", vi->i_ino);
2240                         // FIXME:  Do something!!!
2241                 }
2242         }
2243 #endif /* NTFS_RW */
2244 
2245         /* No need to lock at this stage as no one else has a reference. */
2246         if (ni->nr_extents > 0) {
2247                 int i;
2248 
2249                 for (i = 0; i < ni->nr_extents; i++)
2250                         ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
2251                 kfree(ni->ext.extent_ntfs_inos);
2252         }
2253 
2254         __ntfs_clear_inode(ni);
2255 
2256         if (NInoAttr(ni)) {
2257                 /* Release the base inode if we are holding it. */
2258                 if (ni->nr_extents == -1) {
2259                         iput(VFS_I(ni->ext.base_ntfs_ino));
2260                         ni->nr_extents = 0;
2261                         ni->ext.base_ntfs_ino = NULL;
2262                 }
2263         }
2264         BUG_ON(ni->page);
2265         if (!atomic_dec_and_test(&ni->count))
2266                 BUG();
2267         return;
2268 }
2269 
2270 /**
2271  * ntfs_show_options - show mount options in /proc/mounts
2272  * @sf:         seq_file in which to write our mount options
2273  * @root:       root of the mounted tree whose mount options to display
2274  *
2275  * Called by the VFS once for each mounted ntfs volume when someone reads
2276  * /proc/mounts in order to display the NTFS specific mount options of each
2277  * mount. The mount options of fs specified by @root are written to the seq file
2278  * @sf and success is returned.
2279  */
2280 int ntfs_show_options(struct seq_file *sf, struct dentry *root)
2281 {
2282         ntfs_volume *vol = NTFS_SB(root->d_sb);
2283         int i;
2284 
2285         seq_printf(sf, ",uid=%i", from_kuid_munged(&init_user_ns, vol->uid));
2286         seq_printf(sf, ",gid=%i", from_kgid_munged(&init_user_ns, vol->gid));
2287         if (vol->fmask == vol->dmask)
2288                 seq_printf(sf, ",umask=0%o", vol->fmask);
2289         else {
2290                 seq_printf(sf, ",fmask=0%o", vol->fmask);
2291                 seq_printf(sf, ",dmask=0%o", vol->dmask);
2292         }
2293         seq_printf(sf, ",nls=%s", vol->nls_map->charset);
2294         if (NVolCaseSensitive(vol))
2295                 seq_printf(sf, ",case_sensitive");
2296         if (NVolShowSystemFiles(vol))
2297                 seq_printf(sf, ",show_sys_files");
2298         if (!NVolSparseEnabled(vol))
2299                 seq_printf(sf, ",disable_sparse");
2300         for (i = 0; on_errors_arr[i].val; i++) {
2301                 if (on_errors_arr[i].val & vol->on_errors)
2302                         seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
2303         }
2304         seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
2305         return 0;
2306 }
2307 
2308 #ifdef NTFS_RW
2309 
2310 static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
2311                 "chkdsk.";
2312 
2313 /**
2314  * ntfs_truncate - called when the i_size of an ntfs inode is changed
2315  * @vi:         inode for which the i_size was changed
2316  *
2317  * We only support i_size changes for normal files at present, i.e. not
2318  * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
2319  * below.
2320  *
2321  * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
2322  * that the change is allowed.
2323  *
2324  * This implies for us that @vi is a file inode rather than a directory, index,
2325  * or attribute inode as well as that @vi is a base inode.
2326  *
2327  * Returns 0 on success or -errno on error.
2328  *
2329  * Called with ->i_mutex held.
2330  */
2331 int ntfs_truncate(struct inode *vi)
2332 {
2333         s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
2334         VCN highest_vcn;
2335         unsigned long flags;
2336         ntfs_inode *base_ni, *ni = NTFS_I(vi);
2337         ntfs_volume *vol = ni->vol;
2338         ntfs_attr_search_ctx *ctx;
2339         MFT_RECORD *m;
2340         ATTR_RECORD *a;
2341         const char *te = "  Leaving file length out of sync with i_size.";
2342         int err, mp_size, size_change, alloc_change;
2343         u32 attr_len;
2344 
2345         ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2346         BUG_ON(NInoAttr(ni));
2347         BUG_ON(S_ISDIR(vi->i_mode));
2348         BUG_ON(NInoMstProtected(ni));
2349         BUG_ON(ni->nr_extents < 0);
2350 retry_truncate:
2351         /*
2352          * Lock the runlist for writing and map the mft record to ensure it is
2353          * safe to mess with the attribute runlist and sizes.
2354          */
2355         down_write(&ni->runlist.lock);
2356         if (!NInoAttr(ni))
2357                 base_ni = ni;
2358         else
2359                 base_ni = ni->ext.base_ntfs_ino;
2360         m = map_mft_record(base_ni);
2361         if (IS_ERR(m)) {
2362                 err = PTR_ERR(m);
2363                 ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
2364                                 "(error code %d).%s", vi->i_ino, err, te);
2365                 ctx = NULL;
2366                 m = NULL;
2367                 goto old_bad_out;
2368         }
2369         ctx = ntfs_attr_get_search_ctx(base_ni, m);
2370         if (unlikely(!ctx)) {
2371                 ntfs_error(vi->i_sb, "Failed to allocate a search context for "
2372                                 "inode 0x%lx (not enough memory).%s",
2373                                 vi->i_ino, te);
2374                 err = -ENOMEM;
2375                 goto old_bad_out;
2376         }
2377         err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2378                         CASE_SENSITIVE, 0, NULL, 0, ctx);
2379         if (unlikely(err)) {
2380                 if (err == -ENOENT) {
2381                         ntfs_error(vi->i_sb, "Open attribute is missing from "
2382                                         "mft record.  Inode 0x%lx is corrupt.  "
2383                                         "Run chkdsk.%s", vi->i_ino, te);
2384                         err = -EIO;
2385                 } else
2386                         ntfs_error(vi->i_sb, "Failed to lookup attribute in "
2387                                         "inode 0x%lx (error code %d).%s",
2388                                         vi->i_ino, err, te);
2389                 goto old_bad_out;
2390         }
2391         m = ctx->mrec;
2392         a = ctx->attr;
2393         /*
2394          * The i_size of the vfs inode is the new size for the attribute value.
2395          */
2396         new_size = i_size_read(vi);
2397         /* The current size of the attribute value is the old size. */
2398         old_size = ntfs_attr_size(a);
2399         /* Calculate the new allocated size. */
2400         if (NInoNonResident(ni))
2401                 new_alloc_size = (new_size + vol->cluster_size - 1) &
2402                                 ~(s64)vol->cluster_size_mask;
2403         else
2404                 new_alloc_size = (new_size + 7) & ~7;
2405         /* The current allocated size is the old allocated size. */
2406         read_lock_irqsave(&ni->size_lock, flags);
2407         old_alloc_size = ni->allocated_size;
2408         read_unlock_irqrestore(&ni->size_lock, flags);
2409         /*
2410          * The change in the file size.  This will be 0 if no change, >0 if the
2411          * size is growing, and <0 if the size is shrinking.
2412          */
2413         size_change = -1;
2414         if (new_size - old_size >= 0) {
2415                 size_change = 1;
2416                 if (new_size == old_size)
2417                         size_change = 0;
2418         }
2419         /* As above for the allocated size. */
2420         alloc_change = -1;
2421         if (new_alloc_size - old_alloc_size >= 0) {
2422                 alloc_change = 1;
2423                 if (new_alloc_size == old_alloc_size)
2424                         alloc_change = 0;
2425         }
2426         /*
2427          * If neither the size nor the allocation are being changed there is
2428          * nothing to do.
2429          */
2430         if (!size_change && !alloc_change)
2431                 goto unm_done;
2432         /* If the size is changing, check if new size is allowed in $AttrDef. */
2433         if (size_change) {
2434                 err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
2435                 if (unlikely(err)) {
2436                         if (err == -ERANGE) {
2437                                 ntfs_error(vol->sb, "Truncate would cause the "
2438                                                 "inode 0x%lx to %simum size "
2439                                                 "for its attribute type "
2440                                                 "(0x%x).  Aborting truncate.",
2441                                                 vi->i_ino,
2442                                                 new_size > old_size ? "exceed "
2443                                                 "the max" : "go under the min",
2444                                                 le32_to_cpu(ni->type));
2445                                 err = -EFBIG;
2446                         } else {
2447                                 ntfs_error(vol->sb, "Inode 0x%lx has unknown "
2448                                                 "attribute type 0x%x.  "
2449                                                 "Aborting truncate.",
2450                                                 vi->i_ino,
2451                                                 le32_to_cpu(ni->type));
2452                                 err = -EIO;
2453                         }
2454                         /* Reset the vfs inode size to the old size. */
2455                         i_size_write(vi, old_size);
2456                         goto err_out;
2457                 }
2458         }
2459         if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2460                 ntfs_warning(vi->i_sb, "Changes in inode size are not "
2461                                 "supported yet for %s files, ignoring.",
2462                                 NInoCompressed(ni) ? "compressed" :
2463                                 "encrypted");
2464                 err = -EOPNOTSUPP;
2465                 goto bad_out;
2466         }
2467         if (a->non_resident)
2468                 goto do_non_resident_truncate;
2469         BUG_ON(NInoNonResident(ni));
2470         /* Resize the attribute record to best fit the new attribute size. */
2471         if (new_size < vol->mft_record_size &&
2472                         !ntfs_resident_attr_value_resize(m, a, new_size)) {
2473                 /* The resize succeeded! */
2474                 flush_dcache_mft_record_page(ctx->ntfs_ino);
2475                 mark_mft_record_dirty(ctx->ntfs_ino);
2476                 write_lock_irqsave(&ni->size_lock, flags);
2477                 /* Update the sizes in the ntfs inode and all is done. */
2478                 ni->allocated_size = le32_to_cpu(a->length) -
2479                                 le16_to_cpu(a->data.resident.value_offset);
2480                 /*
2481                  * Note ntfs_resident_attr_value_resize() has already done any
2482                  * necessary data clearing in the attribute record.  When the
2483                  * file is being shrunk vmtruncate() will already have cleared
2484                  * the top part of the last partial page, i.e. since this is
2485                  * the resident case this is the page with index 0.  However,
2486                  * when the file is being expanded, the page cache page data
2487                  * between the old data_size, i.e. old_size, and the new_size
2488                  * has not been zeroed.  Fortunately, we do not need to zero it
2489                  * either since on one hand it will either already be zero due
2490                  * to both readpage and writepage clearing partial page data
2491                  * beyond i_size in which case there is nothing to do or in the
2492                  * case of the file being mmap()ped at the same time, POSIX
2493                  * specifies that the behaviour is unspecified thus we do not
2494                  * have to do anything.  This means that in our implementation
2495                  * in the rare case that the file is mmap()ped and a write
2496                  * occurred into the mmap()ped region just beyond the file size
2497                  * and writepage has not yet been called to write out the page
2498                  * (which would clear the area beyond the file size) and we now
2499                  * extend the file size to incorporate this dirty region
2500                  * outside the file size, a write of the page would result in
2501                  * this data being written to disk instead of being cleared.
2502                  * Given both POSIX and the Linux mmap(2) man page specify that
2503                  * this corner case is undefined, we choose to leave it like
2504                  * that as this is much simpler for us as we cannot lock the
2505                  * relevant page now since we are holding too many ntfs locks
2506                  * which would result in a lock reversal deadlock.
2507                  */
2508                 ni->initialized_size = new_size;
2509                 write_unlock_irqrestore(&ni->size_lock, flags);
2510                 goto unm_done;
2511         }
2512         /* If the above resize failed, this must be an attribute extension. */
2513         BUG_ON(size_change < 0);
2514         /*
2515          * We have to drop all the locks so we can call
2516          * ntfs_attr_make_non_resident().  This could be optimised by try-
2517          * locking the first page cache page and only if that fails dropping
2518          * the locks, locking the page, and redoing all the locking and
2519          * lookups.  While this would be a huge optimisation, it is not worth
2520          * it as this is definitely a slow code path as it only ever can happen
2521          * once for any given file.
2522          */
2523         ntfs_attr_put_search_ctx(ctx);
2524         unmap_mft_record(base_ni);
2525         up_write(&ni->runlist.lock);
2526         /*
2527          * Not enough space in the mft record, try to make the attribute
2528          * non-resident and if successful restart the truncation process.
2529          */
2530         err = ntfs_attr_make_non_resident(ni, old_size);
2531         if (likely(!err))
2532                 goto retry_truncate;
2533         /*
2534          * Could not make non-resident.  If this is due to this not being
2535          * permitted for this attribute type or there not being enough space,
2536          * try to make other attributes non-resident.  Otherwise fail.
2537          */
2538         if (unlikely(err != -EPERM && err != -ENOSPC)) {
2539                 ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
2540                                 "type 0x%x, because the conversion from "
2541                                 "resident to non-resident attribute failed "
2542                                 "with error code %i.", vi->i_ino,
2543                                 (unsigned)le32_to_cpu(ni->type), err);
2544                 if (err != -ENOMEM)
2545                         err = -EIO;
2546                 goto conv_err_out;
2547         }
2548         /* TODO: Not implemented from here, abort. */
2549         if (err == -ENOSPC)
2550                 ntfs_error(vol->sb, "Not enough space in the mft record/on "
2551                                 "disk for the non-resident attribute value.  "
2552                                 "This case is not implemented yet.");
2553         else /* if (err == -EPERM) */
2554                 ntfs_error(vol->sb, "This attribute type may not be "
2555                                 "non-resident.  This case is not implemented "
2556                                 "yet.");
2557         err = -EOPNOTSUPP;
2558         goto conv_err_out;
2559 #if 0
2560         // TODO: Attempt to make other attributes non-resident.
2561         if (!err)
2562                 goto do_resident_extend;
2563         /*
2564          * Both the attribute list attribute and the standard information
2565          * attribute must remain in the base inode.  Thus, if this is one of
2566          * these attributes, we have to try to move other attributes out into
2567          * extent mft records instead.
2568          */
2569         if (ni->type == AT_ATTRIBUTE_LIST ||
2570                         ni->type == AT_STANDARD_INFORMATION) {
2571                 // TODO: Attempt to move other attributes into extent mft
2572                 // records.
2573                 err = -EOPNOTSUPP;
2574                 if (!err)
2575                         goto do_resident_extend;
2576                 goto err_out;
2577         }
2578         // TODO: Attempt to move this attribute to an extent mft record, but
2579         // only if it is not already the only attribute in an mft record in
2580         // which case there would be nothing to gain.
2581         err = -EOPNOTSUPP;
2582         if (!err)
2583                 goto do_resident_extend;
2584         /* There is nothing we can do to make enough space. )-: */
2585         goto err_out;
2586 #endif
2587 do_non_resident_truncate:
2588         BUG_ON(!NInoNonResident(ni));
2589         if (alloc_change < 0) {
2590                 highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2591                 if (highest_vcn > 0 &&
2592                                 old_alloc_size >> vol->cluster_size_bits >
2593                                 highest_vcn + 1) {
2594                         /*
2595                          * This attribute has multiple extents.  Not yet
2596                          * supported.
2597                          */
2598                         ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
2599                                         "attribute type 0x%x, because the "
2600                                         "attribute is highly fragmented (it "
2601                                         "consists of multiple extents) and "
2602                                         "this case is not implemented yet.",
2603                                         vi->i_ino,
2604                                         (unsigned)le32_to_cpu(ni->type));
2605                         err = -EOPNOTSUPP;
2606                         goto bad_out;
2607                 }
2608         }
2609         /*
2610          * If the size is shrinking, need to reduce the initialized_size and
2611          * the data_size before reducing the allocation.
2612          */
2613         if (size_change < 0) {
2614                 /*
2615                  * Make the valid size smaller (i_size is already up-to-date).
2616                  */
2617                 write_lock_irqsave(&ni->size_lock, flags);
2618                 if (new_size < ni->initialized_size) {
2619                         ni->initialized_size = new_size;
2620                         a->data.non_resident.initialized_size =
2621                                         cpu_to_sle64(new_size);
2622                 }
2623                 a->data.non_resident.data_size = cpu_to_sle64(new_size);
2624                 write_unlock_irqrestore(&ni->size_lock, flags);
2625                 flush_dcache_mft_record_page(ctx->ntfs_ino);
2626                 mark_mft_record_dirty(ctx->ntfs_ino);
2627                 /* If the allocated size is not changing, we are done. */
2628                 if (!alloc_change)
2629                         goto unm_done;
2630                 /*
2631                  * If the size is shrinking it makes no sense for the
2632                  * allocation to be growing.
2633                  */
2634                 BUG_ON(alloc_change > 0);
2635         } else /* if (size_change >= 0) */ {
2636                 /*
2637                  * The file size is growing or staying the same but the
2638                  * allocation can be shrinking, growing or staying the same.
2639                  */
2640                 if (alloc_change > 0) {
2641                         /*
2642                          * We need to extend the allocation and possibly update
2643                          * the data size.  If we are updating the data size,
2644                          * since we are not touching the initialized_size we do
2645                          * not need to worry about the actual data on disk.
2646                          * And as far as the page cache is concerned, there
2647                          * will be no pages beyond the old data size and any
2648                          * partial region in the last page between the old and
2649                          * new data size (or the end of the page if the new
2650                          * data size is outside the page) does not need to be
2651                          * modified as explained above for the resident
2652                          * attribute truncate case.  To do this, we simply drop
2653                          * the locks we hold and leave all the work to our
2654                          * friendly helper ntfs_attr_extend_allocation().
2655                          */
2656                         ntfs_attr_put_search_ctx(ctx);
2657                         unmap_mft_record(base_ni);
2658                         up_write(&ni->runlist.lock);
2659                         err = ntfs_attr_extend_allocation(ni, new_size,
2660                                         size_change > 0 ? new_size : -1, -1);
2661                         /*
2662                          * ntfs_attr_extend_allocation() will have done error
2663                          * output already.
2664                          */
2665                         goto done;
2666                 }
2667                 if (!alloc_change)
2668                         goto alloc_done;
2669         }
2670         /* alloc_change < 0 */
2671         /* Free the clusters. */
2672         nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
2673                         vol->cluster_size_bits, -1, ctx);
2674         m = ctx->mrec;
2675         a = ctx->attr;
2676         if (unlikely(nr_freed < 0)) {
2677                 ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
2678                                 "%lli).  Unmount and run chkdsk to recover "
2679                                 "the lost cluster(s).", (long long)nr_freed);
2680                 NVolSetErrors(vol);
2681                 nr_freed = 0;
2682         }
2683         /* Truncate the runlist. */
2684         err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
2685                         new_alloc_size >> vol->cluster_size_bits);
2686         /*
2687          * If the runlist truncation failed and/or the search context is no
2688          * longer valid, we cannot resize the attribute record or build the
2689          * mapping pairs array thus we mark the inode bad so that no access to
2690          * the freed clusters can happen.
2691          */
2692         if (unlikely(err || IS_ERR(m))) {
2693                 ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
2694                                 IS_ERR(m) ?
2695                                 "restore attribute search context" :
2696                                 "truncate attribute runlist",
2697                                 IS_ERR(m) ? PTR_ERR(m) : err, es);
2698                 err = -EIO;
2699                 goto bad_out;
2700         }
2701         /* Get the size for the shrunk mapping pairs array for the runlist. */
2702         mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
2703         if (unlikely(mp_size <= 0)) {
2704                 ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2705                                 "attribute type 0x%x, because determining the "
2706                                 "size for the mapping pairs failed with error "
2707                                 "code %i.%s", vi->i_ino,
2708                                 (unsigned)le32_to_cpu(ni->type), mp_size, es);
2709                 err = -EIO;
2710                 goto bad_out;
2711         }
2712         /*
2713          * Shrink the attribute record for the new mapping pairs array.  Note,
2714          * this cannot fail since we are making the attribute smaller thus by
2715          * definition there is enough space to do so.
2716          */
2717         attr_len = le32_to_cpu(a->length);
2718         err = ntfs_attr_record_resize(m, a, mp_size +
2719                         le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2720         BUG_ON(err);
2721         /*
2722          * Generate the mapping pairs array directly into the attribute record.
2723          */
2724         err = ntfs_mapping_pairs_build(vol, (u8*)a +
2725                         le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2726                         mp_size, ni->runlist.rl, 0, -1, NULL);
2727         if (unlikely(err)) {
2728                 ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2729                                 "attribute type 0x%x, because building the "
2730                                 "mapping pairs failed with error code %i.%s",
2731                                 vi->i_ino, (unsigned)le32_to_cpu(ni->type),
2732                                 err, es);
2733                 err = -EIO;
2734                 goto bad_out;
2735         }
2736         /* Update the allocated/compressed size as well as the highest vcn. */
2737         a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2738                         vol->cluster_size_bits) - 1);
2739         write_lock_irqsave(&ni->size_lock, flags);
2740         ni->allocated_size = new_alloc_size;
2741         a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2742         if (NInoSparse(ni) || NInoCompressed(ni)) {
2743                 if (nr_freed) {
2744                         ni->itype.compressed.size -= nr_freed <<
2745                                         vol->cluster_size_bits;
2746                         BUG_ON(ni->itype.compressed.size < 0);
2747                         a->data.non_resident.compressed_size = cpu_to_sle64(
2748                                         ni->itype.compressed.size);
2749                         vi->i_blocks = ni->itype.compressed.size >> 9;
2750                 }
2751         } else
2752                 vi->i_blocks = new_alloc_size >> 9;
2753         write_unlock_irqrestore(&ni->size_lock, flags);
2754         /*
2755          * We have shrunk the allocation.  If this is a shrinking truncate we
2756          * have already dealt with the initialized_size and the data_size above
2757          * and we are done.  If the truncate is only changing the allocation
2758          * and not the data_size, we are also done.  If this is an extending
2759          * truncate, need to extend the data_size now which is ensured by the
2760          * fact that @size_change is positive.
2761          */
2762 alloc_done:
2763         /*
2764          * If the size is growing, need to update it now.  If it is shrinking,
2765          * we have already updated it above (before the allocation change).
2766          */
2767         if (size_change > 0)
2768                 a->data.non_resident.data_size = cpu_to_sle64(new_size);
2769         /* Ensure the modified mft record is written out. */
2770         flush_dcache_mft_record_page(ctx->ntfs_ino);
2771         mark_mft_record_dirty(ctx->ntfs_ino);
2772 unm_done:
2773         ntfs_attr_put_search_ctx(ctx);
2774         unmap_mft_record(base_ni);
2775         up_write(&ni->runlist.lock);
2776 done:
2777         /* Update the mtime and ctime on the base inode. */
2778         /* normally ->truncate shouldn't update ctime or mtime,
2779          * but ntfs did before so it got a copy & paste version
2780          * of file_update_time.  one day someone should fix this
2781          * for real.
2782          */
2783         if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
2784                 struct timespec64 now = current_time(VFS_I(base_ni));
2785                 int sync_it = 0;
2786 
2787                 if (!timespec64_equal(&VFS_I(base_ni)->i_mtime, &now) ||
2788                     !timespec64_equal(&VFS_I(base_ni)->i_ctime, &now))
2789                         sync_it = 1;
2790                 VFS_I(base_ni)->i_mtime = now;
2791                 VFS_I(base_ni)->i_ctime = now;
2792 
2793                 if (sync_it)
2794                         mark_inode_dirty_sync(VFS_I(base_ni));
2795         }
2796 
2797         if (likely(!err)) {
2798                 NInoClearTruncateFailed(ni);
2799                 ntfs_debug("Done.");
2800         }
2801         return err;
2802 old_bad_out:
2803         old_size = -1;
2804 bad_out:
2805         if (err != -ENOMEM && err != -EOPNOTSUPP)
2806                 NVolSetErrors(vol);
2807         if (err != -EOPNOTSUPP)
2808                 NInoSetTruncateFailed(ni);
2809         else if (old_size >= 0)
2810                 i_size_write(vi, old_size);
2811 err_out:
2812         if (ctx)
2813                 ntfs_attr_put_search_ctx(ctx);
2814         if (m)
2815                 unmap_mft_record(base_ni);
2816         up_write(&ni->runlist.lock);
2817 out:
2818         ntfs_debug("Failed.  Returning error code %i.", err);
2819         return err;
2820 conv_err_out:
2821         if (err != -ENOMEM && err != -EOPNOTSUPP)
2822                 NVolSetErrors(vol);
2823         if (err != -EOPNOTSUPP)
2824                 NInoSetTruncateFailed(ni);
2825         else
2826                 i_size_write(vi, old_size);
2827         goto out;
2828 }
2829 
2830 /**
2831  * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
2832  * @vi:         inode for which the i_size was changed
2833  *
2834  * Wrapper for ntfs_truncate() that has no return value.
2835  *
2836  * See ntfs_truncate() description above for details.
2837  */
2838 #ifdef NTFS_RW
2839 void ntfs_truncate_vfs(struct inode *vi) {
2840         ntfs_truncate(vi);
2841 }
2842 #endif
2843 
2844 /**
2845  * ntfs_setattr - called from notify_change() when an attribute is being changed
2846  * @dentry:     dentry whose attributes to change
2847  * @attr:       structure describing the attributes and the changes
2848  *
2849  * We have to trap VFS attempts to truncate the file described by @dentry as
2850  * soon as possible, because we do not implement changes in i_size yet.  So we
2851  * abort all i_size changes here.
2852  *
2853  * We also abort all changes of user, group, and mode as we do not implement
2854  * the NTFS ACLs yet.
2855  *
2856  * Called with ->i_mutex held.
2857  */
2858 int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
2859 {
2860         struct inode *vi = d_inode(dentry);
2861         int err;
2862         unsigned int ia_valid = attr->ia_valid;
2863 
2864         err = setattr_prepare(dentry, attr);
2865         if (err)
2866                 goto out;
2867         /* We do not support NTFS ACLs yet. */
2868         if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
2869                 ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
2870                                 "supported yet, ignoring.");
2871                 err = -EOPNOTSUPP;
2872                 goto out;
2873         }
2874         if (ia_valid & ATTR_SIZE) {
2875                 if (attr->ia_size != i_size_read(vi)) {
2876                         ntfs_inode *ni = NTFS_I(vi);
2877                         /*
2878                          * FIXME: For now we do not support resizing of
2879                          * compressed or encrypted files yet.
2880                          */
2881                         if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2882                                 ntfs_warning(vi->i_sb, "Changes in inode size "
2883                                                 "are not supported yet for "
2884                                                 "%s files, ignoring.",
2885                                                 NInoCompressed(ni) ?
2886                                                 "compressed" : "encrypted");
2887                                 err = -EOPNOTSUPP;
2888                         } else {
2889                                 truncate_setsize(vi, attr->ia_size);
2890                                 ntfs_truncate_vfs(vi);
2891                         }
2892                         if (err || ia_valid == ATTR_SIZE)
2893                                 goto out;
2894                 } else {
2895                         /*
2896                          * We skipped the truncate but must still update
2897                          * timestamps.
2898                          */
2899                         ia_valid |= ATTR_MTIME | ATTR_CTIME;
2900                 }
2901         }
2902         if (ia_valid & ATTR_ATIME)
2903                 vi->i_atime = timespec64_trunc(attr->ia_atime,
2904                                                vi->i_sb->s_time_gran);
2905         if (ia_valid & ATTR_MTIME)
2906                 vi->i_mtime = timespec64_trunc(attr->ia_mtime,
2907                                                vi->i_sb->s_time_gran);
2908         if (ia_valid & ATTR_CTIME)
2909                 vi->i_ctime = timespec64_trunc(attr->ia_ctime,
2910                                                vi->i_sb->s_time_gran);
2911         mark_inode_dirty(vi);
2912 out:
2913         return err;
2914 }
2915 
2916 /**
2917  * ntfs_write_inode - write out a dirty inode
2918  * @vi:         inode to write out
2919  * @sync:       if true, write out synchronously
2920  *
2921  * Write out a dirty inode to disk including any extent inodes if present.
2922  *
2923  * If @sync is true, commit the inode to disk and wait for io completion.  This
2924  * is done using write_mft_record().
2925  *
2926  * If @sync is false, just schedule the write to happen but do not wait for i/o
2927  * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
2928  * marking the page (and in this case mft record) dirty but we do not implement
2929  * this yet as write_mft_record() largely ignores the @sync parameter and
2930  * always performs synchronous writes.
2931  *
2932  * Return 0 on success and -errno on error.
2933  */
2934 int __ntfs_write_inode(struct inode *vi, int sync)
2935 {
2936         sle64 nt;
2937         ntfs_inode *ni = NTFS_I(vi);
2938         ntfs_attr_search_ctx *ctx;
2939         MFT_RECORD *m;
2940         STANDARD_INFORMATION *si;
2941         int err = 0;
2942         bool modified = false;
2943 
2944         ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
2945                         vi->i_ino);
2946         /*
2947          * Dirty attribute inodes are written via their real inodes so just
2948          * clean them here.  Access time updates are taken care off when the
2949          * real inode is written.
2950          */
2951         if (NInoAttr(ni)) {
2952                 NInoClearDirty(ni);
2953                 ntfs_debug("Done.");
2954                 return 0;
2955         }
2956         /* Map, pin, and lock the mft record belonging to the inode. */
2957         m = map_mft_record(ni);
2958         if (IS_ERR(m)) {
2959                 err = PTR_ERR(m);
2960                 goto err_out;
2961         }
2962         /* Update the access times in the standard information attribute. */
2963         ctx = ntfs_attr_get_search_ctx(ni, m);
2964         if (unlikely(!ctx)) {
2965                 err = -ENOMEM;
2966                 goto unm_err_out;
2967         }
2968         err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
2969                         CASE_SENSITIVE, 0, NULL, 0, ctx);
2970         if (unlikely(err)) {
2971                 ntfs_attr_put_search_ctx(ctx);
2972                 goto unm_err_out;
2973         }
2974         si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
2975                         le16_to_cpu(ctx->attr->data.resident.value_offset));
2976         /* Update the access times if they have changed. */
2977         nt = utc2ntfs(vi->i_mtime);
2978         if (si->last_data_change_time != nt) {
2979                 ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
2980                                 "new = 0x%llx", vi->i_ino, (long long)
2981                                 sle64_to_cpu(si->last_data_change_time),
2982                                 (long long)sle64_to_cpu(nt));
2983                 si->last_data_change_time = nt;
2984                 modified = true;
2985         }
2986         nt = utc2ntfs(vi->i_ctime);
2987         if (si->last_mft_change_time != nt) {
2988                 ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
2989                                 "new = 0x%llx", vi->i_ino, (long long)
2990                                 sle64_to_cpu(si->last_mft_change_time),
2991                                 (long long)sle64_to_cpu(nt));
2992                 si->last_mft_change_time = nt;
2993                 modified = true;
2994         }
2995         nt = utc2ntfs(vi->i_atime);
2996         if (si->last_access_time != nt) {
2997                 ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
2998                                 "new = 0x%llx", vi->i_ino,
2999                                 (long long)sle64_to_cpu(si->last_access_time),
3000                                 (long long)sle64_to_cpu(nt));
3001                 si->last_access_time = nt;
3002                 modified = true;
3003         }
3004         /*
3005          * If we just modified the standard information attribute we need to
3006          * mark the mft record it is in dirty.  We do this manually so that
3007          * mark_inode_dirty() is not called which would redirty the inode and
3008          * hence result in an infinite loop of trying to write the inode.
3009          * There is no need to mark the base inode nor the base mft record
3010          * dirty, since we are going to write this mft record below in any case
3011          * and the base mft record may actually not have been modified so it
3012          * might not need to be written out.
3013          * NOTE: It is not a problem when the inode for $MFT itself is being
3014          * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
3015          * on the $MFT inode and hence ntfs_write_inode() will not be
3016          * re-invoked because of it which in turn is ok since the dirtied mft
3017          * record will be cleaned and written out to disk below, i.e. before
3018          * this function returns.
3019          */
3020         if (modified) {
3021                 flush_dcache_mft_record_page(ctx->ntfs_ino);
3022                 if (!NInoTestSetDirty(ctx->ntfs_ino))
3023                         mark_ntfs_record_dirty(ctx->ntfs_ino->page,
3024                                         ctx->ntfs_ino->page_ofs);
3025         }
3026         ntfs_attr_put_search_ctx(ctx);
3027         /* Now the access times are updated, write the base mft record. */
3028         if (NInoDirty(ni))
3029                 err = write_mft_record(ni, m, sync);
3030         /* Write all attached extent mft records. */
3031         mutex_lock(&ni->extent_lock);
3032         if (ni->nr_extents > 0) {
3033                 ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
3034                 int i;
3035 
3036                 ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
3037                 for (i = 0; i < ni->nr_extents; i++) {
3038                         ntfs_inode *tni = extent_nis[i];
3039 
3040                         if (NInoDirty(tni)) {
3041                                 MFT_RECORD *tm = map_mft_record(tni);
3042                                 int ret;
3043 
3044                                 if (IS_ERR(tm)) {
3045                                         if (!err || err == -ENOMEM)
3046                                                 err = PTR_ERR(tm);
3047                                         continue;
3048                                 }
3049                                 ret = write_mft_record(tni, tm, sync);
3050                                 unmap_mft_record(tni);
3051                                 if (unlikely(ret)) {
3052                                         if (!err || err == -ENOMEM)
3053                                                 err = ret;
3054                                 }
3055                         }
3056                 }
3057         }
3058         mutex_unlock(&ni->extent_lock);
3059         unmap_mft_record(ni);
3060         if (unlikely(err))
3061                 goto err_out;
3062         ntfs_debug("Done.");
3063         return 0;
3064 unm_err_out:
3065         unmap_mft_record(ni);
3066 err_out:
3067         if (err == -ENOMEM) {
3068                 ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
3069                                 "Marking the inode dirty again, so the VFS "
3070                                 "retries later.");
3071                 mark_inode_dirty(vi);
3072         } else {
3073                 ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
3074                 NVolSetErrors(ni->vol);
3075         }
3076         return err;
3077 }
3078 
3079 #endif /* NTFS_RW */
3080 

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