reiserfs: rename p_s_inode to inode
[linux-2.6.git] / fs / reiserfs / stree.c
1 /*
2  *  Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4
5 /*
6  *  Written by Anatoly P. Pinchuk pap@namesys.botik.ru
7  *  Programm System Institute
8  *  Pereslavl-Zalessky Russia
9  */
10
11 /*
12  *  This file contains functions dealing with S+tree
13  *
14  * B_IS_IN_TREE
15  * copy_item_head
16  * comp_short_keys
17  * comp_keys
18  * comp_short_le_keys
19  * le_key2cpu_key
20  * comp_le_keys
21  * bin_search
22  * get_lkey
23  * get_rkey
24  * key_in_buffer
25  * decrement_bcount
26  * reiserfs_check_path
27  * pathrelse_and_restore
28  * pathrelse
29  * search_by_key_reada
30  * search_by_key
31  * search_for_position_by_key
32  * comp_items
33  * prepare_for_direct_item
34  * prepare_for_direntry_item
35  * prepare_for_delete_or_cut
36  * calc_deleted_bytes_number
37  * init_tb_struct
38  * padd_item
39  * reiserfs_delete_item
40  * reiserfs_delete_solid_item
41  * reiserfs_delete_object
42  * maybe_indirect_to_direct
43  * indirect_to_direct_roll_back
44  * reiserfs_cut_from_item
45  * truncate_directory
46  * reiserfs_do_truncate
47  * reiserfs_paste_into_item
48  * reiserfs_insert_item
49  */
50
51 #include <linux/time.h>
52 #include <linux/string.h>
53 #include <linux/pagemap.h>
54 #include <linux/reiserfs_fs.h>
55 #include <linux/buffer_head.h>
56 #include <linux/quotaops.h>
57
58 /* Does the buffer contain a disk block which is in the tree. */
59 inline int B_IS_IN_TREE(const struct buffer_head *bh)
60 {
61
62         RFALSE(B_LEVEL(bh) > MAX_HEIGHT,
63                "PAP-1010: block (%b) has too big level (%z)", bh, bh);
64
65         return (B_LEVEL(bh) != FREE_LEVEL);
66 }
67
68 //
69 // to gets item head in le form
70 //
71 inline void copy_item_head(struct item_head *p_v_to,
72                            const struct item_head *p_v_from)
73 {
74         memcpy(p_v_to, p_v_from, IH_SIZE);
75 }
76
77 /* k1 is pointer to on-disk structure which is stored in little-endian
78    form. k2 is pointer to cpu variable. For key of items of the same
79    object this returns 0.
80    Returns: -1 if key1 < key2
81    0 if key1 == key2
82    1 if key1 > key2 */
83 inline int comp_short_keys(const struct reiserfs_key *le_key,
84                            const struct cpu_key *cpu_key)
85 {
86         __u32 n;
87         n = le32_to_cpu(le_key->k_dir_id);
88         if (n < cpu_key->on_disk_key.k_dir_id)
89                 return -1;
90         if (n > cpu_key->on_disk_key.k_dir_id)
91                 return 1;
92         n = le32_to_cpu(le_key->k_objectid);
93         if (n < cpu_key->on_disk_key.k_objectid)
94                 return -1;
95         if (n > cpu_key->on_disk_key.k_objectid)
96                 return 1;
97         return 0;
98 }
99
100 /* k1 is pointer to on-disk structure which is stored in little-endian
101    form. k2 is pointer to cpu variable.
102    Compare keys using all 4 key fields.
103    Returns: -1 if key1 < key2 0
104    if key1 = key2 1 if key1 > key2 */
105 static inline int comp_keys(const struct reiserfs_key *le_key,
106                             const struct cpu_key *cpu_key)
107 {
108         int retval;
109
110         retval = comp_short_keys(le_key, cpu_key);
111         if (retval)
112                 return retval;
113         if (le_key_k_offset(le_key_version(le_key), le_key) <
114             cpu_key_k_offset(cpu_key))
115                 return -1;
116         if (le_key_k_offset(le_key_version(le_key), le_key) >
117             cpu_key_k_offset(cpu_key))
118                 return 1;
119
120         if (cpu_key->key_length == 3)
121                 return 0;
122
123         /* this part is needed only when tail conversion is in progress */
124         if (le_key_k_type(le_key_version(le_key), le_key) <
125             cpu_key_k_type(cpu_key))
126                 return -1;
127
128         if (le_key_k_type(le_key_version(le_key), le_key) >
129             cpu_key_k_type(cpu_key))
130                 return 1;
131
132         return 0;
133 }
134
135 inline int comp_short_le_keys(const struct reiserfs_key *key1,
136                               const struct reiserfs_key *key2)
137 {
138         __u32 *p_s_1_u32, *p_s_2_u32;
139         int n_key_length = REISERFS_SHORT_KEY_LEN;
140
141         p_s_1_u32 = (__u32 *) key1;
142         p_s_2_u32 = (__u32 *) key2;
143         for (; n_key_length--; ++p_s_1_u32, ++p_s_2_u32) {
144                 if (le32_to_cpu(*p_s_1_u32) < le32_to_cpu(*p_s_2_u32))
145                         return -1;
146                 if (le32_to_cpu(*p_s_1_u32) > le32_to_cpu(*p_s_2_u32))
147                         return 1;
148         }
149         return 0;
150 }
151
152 inline void le_key2cpu_key(struct cpu_key *to, const struct reiserfs_key *from)
153 {
154         int version;
155         to->on_disk_key.k_dir_id = le32_to_cpu(from->k_dir_id);
156         to->on_disk_key.k_objectid = le32_to_cpu(from->k_objectid);
157
158         // find out version of the key
159         version = le_key_version(from);
160         to->version = version;
161         to->on_disk_key.k_offset = le_key_k_offset(version, from);
162         to->on_disk_key.k_type = le_key_k_type(version, from);
163 }
164
165 // this does not say which one is bigger, it only returns 1 if keys
166 // are not equal, 0 otherwise
167 inline int comp_le_keys(const struct reiserfs_key *k1,
168                         const struct reiserfs_key *k2)
169 {
170         return memcmp(k1, k2, sizeof(struct reiserfs_key));
171 }
172
173 /**************************************************************************
174  *  Binary search toolkit function                                        *
175  *  Search for an item in the array by the item key                       *
176  *  Returns:    1 if found,  0 if not found;                              *
177  *        *p_n_pos = number of the searched element if found, else the    *
178  *        number of the first element that is larger than p_v_key.        *
179  **************************************************************************/
180 /* For those not familiar with binary search: n_lbound is the leftmost item that it
181  could be, n_rbound the rightmost item that it could be.  We examine the item
182  halfway between n_lbound and n_rbound, and that tells us either that we can increase
183  n_lbound, or decrease n_rbound, or that we have found it, or if n_lbound <= n_rbound that
184  there are no possible items, and we have not found it. With each examination we
185  cut the number of possible items it could be by one more than half rounded down,
186  or we find it. */
187 static inline int bin_search(const void *p_v_key,       /* Key to search for.                   */
188                              const void *p_v_base,      /* First item in the array.             */
189                              int p_n_num,       /* Number of items in the array.        */
190                              int p_n_width,     /* Item size in the array.
191                                                    searched. Lest the reader be
192                                                    confused, note that this is crafted
193                                                    as a general function, and when it
194                                                    is applied specifically to the array
195                                                    of item headers in a node, p_n_width
196                                                    is actually the item header size not
197                                                    the item size.                      */
198                              int *p_n_pos       /* Number of the searched for element. */
199     )
200 {
201         int n_rbound, n_lbound, n_j;
202
203         for (n_j = ((n_rbound = p_n_num - 1) + (n_lbound = 0)) / 2;
204              n_lbound <= n_rbound; n_j = (n_rbound + n_lbound) / 2)
205                 switch (comp_keys
206                         ((struct reiserfs_key *)((char *)p_v_base +
207                                                  n_j * p_n_width),
208                          (struct cpu_key *)p_v_key)) {
209                 case -1:
210                         n_lbound = n_j + 1;
211                         continue;
212                 case 1:
213                         n_rbound = n_j - 1;
214                         continue;
215                 case 0:
216                         *p_n_pos = n_j;
217                         return ITEM_FOUND;      /* Key found in the array.  */
218                 }
219
220         /* bin_search did not find given key, it returns position of key,
221            that is minimal and greater than the given one. */
222         *p_n_pos = n_lbound;
223         return ITEM_NOT_FOUND;
224 }
225
226 #ifdef CONFIG_REISERFS_CHECK
227 extern struct tree_balance *cur_tb;
228 #endif
229
230 /* Minimal possible key. It is never in the tree. */
231 const struct reiserfs_key MIN_KEY = { 0, 0, {{0, 0},} };
232
233 /* Maximal possible key. It is never in the tree. */
234 static const struct reiserfs_key MAX_KEY = {
235         __constant_cpu_to_le32(0xffffffff),
236         __constant_cpu_to_le32(0xffffffff),
237         {{__constant_cpu_to_le32(0xffffffff),
238           __constant_cpu_to_le32(0xffffffff)},}
239 };
240
241 /* Get delimiting key of the buffer by looking for it in the buffers in the path, starting from the bottom
242    of the path, and going upwards.  We must check the path's validity at each step.  If the key is not in
243    the path, there is no delimiting key in the tree (buffer is first or last buffer in tree), and in this
244    case we return a special key, either MIN_KEY or MAX_KEY. */
245 static inline const struct reiserfs_key *get_lkey(const struct treepath
246                                                   *p_s_chk_path,
247                                                   const struct super_block
248                                                   *sb)
249 {
250         int n_position, n_path_offset = p_s_chk_path->path_length;
251         struct buffer_head *p_s_parent;
252
253         RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET,
254                "PAP-5010: invalid offset in the path");
255
256         /* While not higher in path than first element. */
257         while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
258
259                 RFALSE(!buffer_uptodate
260                        (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
261                        "PAP-5020: parent is not uptodate");
262
263                 /* Parent at the path is not in the tree now. */
264                 if (!B_IS_IN_TREE
265                     (p_s_parent =
266                      PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)))
267                         return &MAX_KEY;
268                 /* Check whether position in the parent is correct. */
269                 if ((n_position =
270                      PATH_OFFSET_POSITION(p_s_chk_path,
271                                           n_path_offset)) >
272                     B_NR_ITEMS(p_s_parent))
273                         return &MAX_KEY;
274                 /* Check whether parent at the path really points to the child. */
275                 if (B_N_CHILD_NUM(p_s_parent, n_position) !=
276                     PATH_OFFSET_PBUFFER(p_s_chk_path,
277                                         n_path_offset + 1)->b_blocknr)
278                         return &MAX_KEY;
279                 /* Return delimiting key if position in the parent is not equal to zero. */
280                 if (n_position)
281                         return B_N_PDELIM_KEY(p_s_parent, n_position - 1);
282         }
283         /* Return MIN_KEY if we are in the root of the buffer tree. */
284         if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->
285             b_blocknr == SB_ROOT_BLOCK(sb))
286                 return &MIN_KEY;
287         return &MAX_KEY;
288 }
289
290 /* Get delimiting key of the buffer at the path and its right neighbor. */
291 inline const struct reiserfs_key *get_rkey(const struct treepath *p_s_chk_path,
292                                            const struct super_block *sb)
293 {
294         int n_position, n_path_offset = p_s_chk_path->path_length;
295         struct buffer_head *p_s_parent;
296
297         RFALSE(n_path_offset < FIRST_PATH_ELEMENT_OFFSET,
298                "PAP-5030: invalid offset in the path");
299
300         while (n_path_offset-- > FIRST_PATH_ELEMENT_OFFSET) {
301
302                 RFALSE(!buffer_uptodate
303                        (PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)),
304                        "PAP-5040: parent is not uptodate");
305
306                 /* Parent at the path is not in the tree now. */
307                 if (!B_IS_IN_TREE
308                     (p_s_parent =
309                      PATH_OFFSET_PBUFFER(p_s_chk_path, n_path_offset)))
310                         return &MIN_KEY;
311                 /* Check whether position in the parent is correct. */
312                 if ((n_position =
313                      PATH_OFFSET_POSITION(p_s_chk_path,
314                                           n_path_offset)) >
315                     B_NR_ITEMS(p_s_parent))
316                         return &MIN_KEY;
317                 /* Check whether parent at the path really points to the child. */
318                 if (B_N_CHILD_NUM(p_s_parent, n_position) !=
319                     PATH_OFFSET_PBUFFER(p_s_chk_path,
320                                         n_path_offset + 1)->b_blocknr)
321                         return &MIN_KEY;
322                 /* Return delimiting key if position in the parent is not the last one. */
323                 if (n_position != B_NR_ITEMS(p_s_parent))
324                         return B_N_PDELIM_KEY(p_s_parent, n_position);
325         }
326         /* Return MAX_KEY if we are in the root of the buffer tree. */
327         if (PATH_OFFSET_PBUFFER(p_s_chk_path, FIRST_PATH_ELEMENT_OFFSET)->
328             b_blocknr == SB_ROOT_BLOCK(sb))
329                 return &MAX_KEY;
330         return &MIN_KEY;
331 }
332
333 /* Check whether a key is contained in the tree rooted from a buffer at a path. */
334 /* This works by looking at the left and right delimiting keys for the buffer in the last path_element in
335    the path.  These delimiting keys are stored at least one level above that buffer in the tree. If the
336    buffer is the first or last node in the tree order then one of the delimiting keys may be absent, and in
337    this case get_lkey and get_rkey return a special key which is MIN_KEY or MAX_KEY. */
338 static inline int key_in_buffer(struct treepath *p_s_chk_path,  /* Path which should be checked.  */
339                                 const struct cpu_key *p_s_key,  /* Key which should be checked.   */
340                                 struct super_block *sb  /* Super block pointer.    */
341     )
342 {
343
344         RFALSE(!p_s_key || p_s_chk_path->path_length < FIRST_PATH_ELEMENT_OFFSET
345                || p_s_chk_path->path_length > MAX_HEIGHT,
346                "PAP-5050: pointer to the key(%p) is NULL or invalid path length(%d)",
347                p_s_key, p_s_chk_path->path_length);
348         RFALSE(!PATH_PLAST_BUFFER(p_s_chk_path)->b_bdev,
349                "PAP-5060: device must not be NODEV");
350
351         if (comp_keys(get_lkey(p_s_chk_path, sb), p_s_key) == 1)
352                 /* left delimiting key is bigger, that the key we look for */
353                 return 0;
354         //  if ( comp_keys(p_s_key, get_rkey(p_s_chk_path, sb)) != -1 )
355         if (comp_keys(get_rkey(p_s_chk_path, sb), p_s_key) != 1)
356                 /* p_s_key must be less than right delimitiing key */
357                 return 0;
358         return 1;
359 }
360
361 int reiserfs_check_path(struct treepath *p)
362 {
363         RFALSE(p->path_length != ILLEGAL_PATH_ELEMENT_OFFSET,
364                "path not properly relsed");
365         return 0;
366 }
367
368 /* Drop the reference to each buffer in a path and restore
369  * dirty bits clean when preparing the buffer for the log.
370  * This version should only be called from fix_nodes() */
371 void pathrelse_and_restore(struct super_block *sb,
372                            struct treepath *p_s_search_path)
373 {
374         int n_path_offset = p_s_search_path->path_length;
375
376         RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
377                "clm-4000: invalid path offset");
378
379         while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET) {
380                 struct buffer_head *bh;
381                 bh = PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--);
382                 reiserfs_restore_prepared_buffer(sb, bh);
383                 brelse(bh);
384         }
385         p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
386 }
387
388 /* Drop the reference to each buffer in a path */
389 void pathrelse(struct treepath *p_s_search_path)
390 {
391         int n_path_offset = p_s_search_path->path_length;
392
393         RFALSE(n_path_offset < ILLEGAL_PATH_ELEMENT_OFFSET,
394                "PAP-5090: invalid path offset");
395
396         while (n_path_offset > ILLEGAL_PATH_ELEMENT_OFFSET)
397                 brelse(PATH_OFFSET_PBUFFER(p_s_search_path, n_path_offset--));
398
399         p_s_search_path->path_length = ILLEGAL_PATH_ELEMENT_OFFSET;
400 }
401
402 static int is_leaf(char *buf, int blocksize, struct buffer_head *bh)
403 {
404         struct block_head *blkh;
405         struct item_head *ih;
406         int used_space;
407         int prev_location;
408         int i;
409         int nr;
410
411         blkh = (struct block_head *)buf;
412         if (blkh_level(blkh) != DISK_LEAF_NODE_LEVEL) {
413                 reiserfs_warning(NULL, "reiserfs-5080",
414                                  "this should be caught earlier");
415                 return 0;
416         }
417
418         nr = blkh_nr_item(blkh);
419         if (nr < 1 || nr > ((blocksize - BLKH_SIZE) / (IH_SIZE + MIN_ITEM_LEN))) {
420                 /* item number is too big or too small */
421                 reiserfs_warning(NULL, "reiserfs-5081",
422                                  "nr_item seems wrong: %z", bh);
423                 return 0;
424         }
425         ih = (struct item_head *)(buf + BLKH_SIZE) + nr - 1;
426         used_space = BLKH_SIZE + IH_SIZE * nr + (blocksize - ih_location(ih));
427         if (used_space != blocksize - blkh_free_space(blkh)) {
428                 /* free space does not match to calculated amount of use space */
429                 reiserfs_warning(NULL, "reiserfs-5082",
430                                  "free space seems wrong: %z", bh);
431                 return 0;
432         }
433         // FIXME: it is_leaf will hit performance too much - we may have
434         // return 1 here
435
436         /* check tables of item heads */
437         ih = (struct item_head *)(buf + BLKH_SIZE);
438         prev_location = blocksize;
439         for (i = 0; i < nr; i++, ih++) {
440                 if (le_ih_k_type(ih) == TYPE_ANY) {
441                         reiserfs_warning(NULL, "reiserfs-5083",
442                                          "wrong item type for item %h",
443                                          ih);
444                         return 0;
445                 }
446                 if (ih_location(ih) >= blocksize
447                     || ih_location(ih) < IH_SIZE * nr) {
448                         reiserfs_warning(NULL, "reiserfs-5084",
449                                          "item location seems wrong: %h",
450                                          ih);
451                         return 0;
452                 }
453                 if (ih_item_len(ih) < 1
454                     || ih_item_len(ih) > MAX_ITEM_LEN(blocksize)) {
455                         reiserfs_warning(NULL, "reiserfs-5085",
456                                          "item length seems wrong: %h",
457                                          ih);
458                         return 0;
459                 }
460                 if (prev_location - ih_location(ih) != ih_item_len(ih)) {
461                         reiserfs_warning(NULL, "reiserfs-5086",
462                                          "item location seems wrong "
463                                          "(second one): %h", ih);
464                         return 0;
465                 }
466                 prev_location = ih_location(ih);
467         }
468
469         // one may imagine much more checks
470         return 1;
471 }
472
473 /* returns 1 if buf looks like an internal node, 0 otherwise */
474 static int is_internal(char *buf, int blocksize, struct buffer_head *bh)
475 {
476         struct block_head *blkh;
477         int nr;
478         int used_space;
479
480         blkh = (struct block_head *)buf;
481         nr = blkh_level(blkh);
482         if (nr <= DISK_LEAF_NODE_LEVEL || nr > MAX_HEIGHT) {
483                 /* this level is not possible for internal nodes */
484                 reiserfs_warning(NULL, "reiserfs-5087",
485                                  "this should be caught earlier");
486                 return 0;
487         }
488
489         nr = blkh_nr_item(blkh);
490         if (nr > (blocksize - BLKH_SIZE - DC_SIZE) / (KEY_SIZE + DC_SIZE)) {
491                 /* for internal which is not root we might check min number of keys */
492                 reiserfs_warning(NULL, "reiserfs-5088",
493                                  "number of key seems wrong: %z", bh);
494                 return 0;
495         }
496
497         used_space = BLKH_SIZE + KEY_SIZE * nr + DC_SIZE * (nr + 1);
498         if (used_space != blocksize - blkh_free_space(blkh)) {
499                 reiserfs_warning(NULL, "reiserfs-5089",
500                                  "free space seems wrong: %z", bh);
501                 return 0;
502         }
503         // one may imagine much more checks
504         return 1;
505 }
506
507 // make sure that bh contains formatted node of reiserfs tree of
508 // 'level'-th level
509 static int is_tree_node(struct buffer_head *bh, int level)
510 {
511         if (B_LEVEL(bh) != level) {
512                 reiserfs_warning(NULL, "reiserfs-5090", "node level %d does "
513                                  "not match to the expected one %d",
514                                  B_LEVEL(bh), level);
515                 return 0;
516         }
517         if (level == DISK_LEAF_NODE_LEVEL)
518                 return is_leaf(bh->b_data, bh->b_size, bh);
519
520         return is_internal(bh->b_data, bh->b_size, bh);
521 }
522
523 #define SEARCH_BY_KEY_READA 16
524
525 /* The function is NOT SCHEDULE-SAFE! */
526 static void search_by_key_reada(struct super_block *s,
527                                 struct buffer_head **bh,
528                                 b_blocknr_t *b, int num)
529 {
530         int i, j;
531
532         for (i = 0; i < num; i++) {
533                 bh[i] = sb_getblk(s, b[i]);
534         }
535         for (j = 0; j < i; j++) {
536                 /*
537                  * note, this needs attention if we are getting rid of the BKL
538                  * you have to make sure the prepared bit isn't set on this buffer
539                  */
540                 if (!buffer_uptodate(bh[j]))
541                         ll_rw_block(READA, 1, bh + j);
542                 brelse(bh[j]);
543         }
544 }
545
546 /**************************************************************************
547  * Algorithm   SearchByKey                                                *
548  *             look for item in the Disk S+Tree by its key                *
549  * Input:  sb   -  super block                                            *
550  *         p_s_key  - pointer to the key to search                        *
551  * Output: ITEM_FOUND, ITEM_NOT_FOUND or IO_ERROR                         *
552  *         p_s_search_path - path from the root to the needed leaf        *
553  **************************************************************************/
554
555 /* This function fills up the path from the root to the leaf as it
556    descends the tree looking for the key.  It uses reiserfs_bread to
557    try to find buffers in the cache given their block number.  If it
558    does not find them in the cache it reads them from disk.  For each
559    node search_by_key finds using reiserfs_bread it then uses
560    bin_search to look through that node.  bin_search will find the
561    position of the block_number of the next node if it is looking
562    through an internal node.  If it is looking through a leaf node
563    bin_search will find the position of the item which has key either
564    equal to given key, or which is the maximal key less than the given
565    key.  search_by_key returns a path that must be checked for the
566    correctness of the top of the path but need not be checked for the
567    correctness of the bottom of the path */
568 /* The function is NOT SCHEDULE-SAFE! */
569 int search_by_key(struct super_block *sb, const struct cpu_key *p_s_key,        /* Key to search. */
570                   struct treepath *p_s_search_path,/* This structure was
571                                                    allocated and initialized
572                                                    by the calling
573                                                    function. It is filled up
574                                                    by this function.  */
575                   int n_stop_level      /* How far down the tree to search. To
576                                            stop at leaf level - set to
577                                            DISK_LEAF_NODE_LEVEL */
578     )
579 {
580         b_blocknr_t n_block_number;
581         int expected_level;
582         struct buffer_head *bh;
583         struct path_element *p_s_last_element;
584         int n_node_level, n_retval;
585         int right_neighbor_of_leaf_node;
586         int fs_gen;
587         struct buffer_head *reada_bh[SEARCH_BY_KEY_READA];
588         b_blocknr_t reada_blocks[SEARCH_BY_KEY_READA];
589         int reada_count = 0;
590
591 #ifdef CONFIG_REISERFS_CHECK
592         int n_repeat_counter = 0;
593 #endif
594
595         PROC_INFO_INC(sb, search_by_key);
596
597         /* As we add each node to a path we increase its count.  This means that
598            we must be careful to release all nodes in a path before we either
599            discard the path struct or re-use the path struct, as we do here. */
600
601         pathrelse(p_s_search_path);
602
603         right_neighbor_of_leaf_node = 0;
604
605         /* With each iteration of this loop we search through the items in the
606            current node, and calculate the next current node(next path element)
607            for the next iteration of this loop.. */
608         n_block_number = SB_ROOT_BLOCK(sb);
609         expected_level = -1;
610         while (1) {
611
612 #ifdef CONFIG_REISERFS_CHECK
613                 if (!(++n_repeat_counter % 50000))
614                         reiserfs_warning(sb, "PAP-5100",
615                                          "%s: there were %d iterations of "
616                                          "while loop looking for key %K",
617                                          current->comm, n_repeat_counter,
618                                          p_s_key);
619 #endif
620
621                 /* prep path to have another element added to it. */
622                 p_s_last_element =
623                     PATH_OFFSET_PELEMENT(p_s_search_path,
624                                          ++p_s_search_path->path_length);
625                 fs_gen = get_generation(sb);
626
627                 /* Read the next tree node, and set the last element in the path to
628                    have a pointer to it. */
629                 if ((bh = p_s_last_element->pe_buffer =
630                      sb_getblk(sb, n_block_number))) {
631                         if (!buffer_uptodate(bh) && reada_count > 1)
632                                 search_by_key_reada(sb, reada_bh,
633                                                     reada_blocks, reada_count);
634                         ll_rw_block(READ, 1, &bh);
635                         wait_on_buffer(bh);
636                         if (!buffer_uptodate(bh))
637                                 goto io_error;
638                 } else {
639                       io_error:
640                         p_s_search_path->path_length--;
641                         pathrelse(p_s_search_path);
642                         return IO_ERROR;
643                 }
644                 reada_count = 0;
645                 if (expected_level == -1)
646                         expected_level = SB_TREE_HEIGHT(sb);
647                 expected_level--;
648
649                 /* It is possible that schedule occurred. We must check whether the key
650                    to search is still in the tree rooted from the current buffer. If
651                    not then repeat search from the root. */
652                 if (fs_changed(fs_gen, sb) &&
653                     (!B_IS_IN_TREE(bh) ||
654                      B_LEVEL(bh) != expected_level ||
655                      !key_in_buffer(p_s_search_path, p_s_key, sb))) {
656                         PROC_INFO_INC(sb, search_by_key_fs_changed);
657                         PROC_INFO_INC(sb, search_by_key_restarted);
658                         PROC_INFO_INC(sb,
659                                       sbk_restarted[expected_level - 1]);
660                         pathrelse(p_s_search_path);
661
662                         /* Get the root block number so that we can repeat the search
663                            starting from the root. */
664                         n_block_number = SB_ROOT_BLOCK(sb);
665                         expected_level = -1;
666                         right_neighbor_of_leaf_node = 0;
667
668                         /* repeat search from the root */
669                         continue;
670                 }
671
672                 /* only check that the key is in the buffer if p_s_key is not
673                    equal to the MAX_KEY. Latter case is only possible in
674                    "finish_unfinished()" processing during mount. */
675                 RFALSE(comp_keys(&MAX_KEY, p_s_key) &&
676                        !key_in_buffer(p_s_search_path, p_s_key, sb),
677                        "PAP-5130: key is not in the buffer");
678 #ifdef CONFIG_REISERFS_CHECK
679                 if (cur_tb) {
680                         print_cur_tb("5140");
681                         reiserfs_panic(sb, "PAP-5140",
682                                        "schedule occurred in do_balance!");
683                 }
684 #endif
685
686                 // make sure, that the node contents look like a node of
687                 // certain level
688                 if (!is_tree_node(bh, expected_level)) {
689                         reiserfs_error(sb, "vs-5150",
690                                        "invalid format found in block %ld. "
691                                        "Fsck?", bh->b_blocknr);
692                         pathrelse(p_s_search_path);
693                         return IO_ERROR;
694                 }
695
696                 /* ok, we have acquired next formatted node in the tree */
697                 n_node_level = B_LEVEL(bh);
698
699                 PROC_INFO_BH_STAT(sb, bh, n_node_level - 1);
700
701                 RFALSE(n_node_level < n_stop_level,
702                        "vs-5152: tree level (%d) is less than stop level (%d)",
703                        n_node_level, n_stop_level);
704
705                 n_retval = bin_search(p_s_key, B_N_PITEM_HEAD(bh, 0),
706                                       B_NR_ITEMS(bh),
707                                       (n_node_level ==
708                                        DISK_LEAF_NODE_LEVEL) ? IH_SIZE :
709                                       KEY_SIZE,
710                                       &(p_s_last_element->pe_position));
711                 if (n_node_level == n_stop_level) {
712                         return n_retval;
713                 }
714
715                 /* we are not in the stop level */
716                 if (n_retval == ITEM_FOUND)
717                         /* item has been found, so we choose the pointer which is to the right of the found one */
718                         p_s_last_element->pe_position++;
719
720                 /* if item was not found we choose the position which is to
721                    the left of the found item. This requires no code,
722                    bin_search did it already. */
723
724                 /* So we have chosen a position in the current node which is
725                    an internal node.  Now we calculate child block number by
726                    position in the node. */
727                 n_block_number =
728                     B_N_CHILD_NUM(bh, p_s_last_element->pe_position);
729
730                 /* if we are going to read leaf nodes, try for read ahead as well */
731                 if ((p_s_search_path->reada & PATH_READA) &&
732                     n_node_level == DISK_LEAF_NODE_LEVEL + 1) {
733                         int pos = p_s_last_element->pe_position;
734                         int limit = B_NR_ITEMS(bh);
735                         struct reiserfs_key *le_key;
736
737                         if (p_s_search_path->reada & PATH_READA_BACK)
738                                 limit = 0;
739                         while (reada_count < SEARCH_BY_KEY_READA) {
740                                 if (pos == limit)
741                                         break;
742                                 reada_blocks[reada_count++] =
743                                     B_N_CHILD_NUM(bh, pos);
744                                 if (p_s_search_path->reada & PATH_READA_BACK)
745                                         pos--;
746                                 else
747                                         pos++;
748
749                                 /*
750                                  * check to make sure we're in the same object
751                                  */
752                                 le_key = B_N_PDELIM_KEY(bh, pos);
753                                 if (le32_to_cpu(le_key->k_objectid) !=
754                                     p_s_key->on_disk_key.k_objectid) {
755                                         break;
756                                 }
757                         }
758                 }
759         }
760 }
761
762 /* Form the path to an item and position in this item which contains
763    file byte defined by p_s_key. If there is no such item
764    corresponding to the key, we point the path to the item with
765    maximal key less than p_s_key, and *p_n_pos_in_item is set to one
766    past the last entry/byte in the item.  If searching for entry in a
767    directory item, and it is not found, *p_n_pos_in_item is set to one
768    entry more than the entry with maximal key which is less than the
769    sought key.
770
771    Note that if there is no entry in this same node which is one more,
772    then we point to an imaginary entry.  for direct items, the
773    position is in units of bytes, for indirect items the position is
774    in units of blocknr entries, for directory items the position is in
775    units of directory entries.  */
776
777 /* The function is NOT SCHEDULE-SAFE! */
778 int search_for_position_by_key(struct super_block *sb,  /* Pointer to the super block.          */
779                                const struct cpu_key *p_cpu_key, /* Key to search (cpu variable)         */
780                                struct treepath *p_s_search_path /* Filled up by this function.          */
781     )
782 {
783         struct item_head *p_le_ih;      /* pointer to on-disk structure */
784         int n_blk_size;
785         loff_t item_offset, offset;
786         struct reiserfs_dir_entry de;
787         int retval;
788
789         /* If searching for directory entry. */
790         if (is_direntry_cpu_key(p_cpu_key))
791                 return search_by_entry_key(sb, p_cpu_key, p_s_search_path,
792                                            &de);
793
794         /* If not searching for directory entry. */
795
796         /* If item is found. */
797         retval = search_item(sb, p_cpu_key, p_s_search_path);
798         if (retval == IO_ERROR)
799                 return retval;
800         if (retval == ITEM_FOUND) {
801
802                 RFALSE(!ih_item_len
803                        (B_N_PITEM_HEAD
804                         (PATH_PLAST_BUFFER(p_s_search_path),
805                          PATH_LAST_POSITION(p_s_search_path))),
806                        "PAP-5165: item length equals zero");
807
808                 pos_in_item(p_s_search_path) = 0;
809                 return POSITION_FOUND;
810         }
811
812         RFALSE(!PATH_LAST_POSITION(p_s_search_path),
813                "PAP-5170: position equals zero");
814
815         /* Item is not found. Set path to the previous item. */
816         p_le_ih =
817             B_N_PITEM_HEAD(PATH_PLAST_BUFFER(p_s_search_path),
818                            --PATH_LAST_POSITION(p_s_search_path));
819         n_blk_size = sb->s_blocksize;
820
821         if (comp_short_keys(&(p_le_ih->ih_key), p_cpu_key)) {
822                 return FILE_NOT_FOUND;
823         }
824         // FIXME: quite ugly this far
825
826         item_offset = le_ih_k_offset(p_le_ih);
827         offset = cpu_key_k_offset(p_cpu_key);
828
829         /* Needed byte is contained in the item pointed to by the path. */
830         if (item_offset <= offset &&
831             item_offset + op_bytes_number(p_le_ih, n_blk_size) > offset) {
832                 pos_in_item(p_s_search_path) = offset - item_offset;
833                 if (is_indirect_le_ih(p_le_ih)) {
834                         pos_in_item(p_s_search_path) /= n_blk_size;
835                 }
836                 return POSITION_FOUND;
837         }
838
839         /* Needed byte is not contained in the item pointed to by the
840            path. Set pos_in_item out of the item. */
841         if (is_indirect_le_ih(p_le_ih))
842                 pos_in_item(p_s_search_path) =
843                     ih_item_len(p_le_ih) / UNFM_P_SIZE;
844         else
845                 pos_in_item(p_s_search_path) = ih_item_len(p_le_ih);
846
847         return POSITION_NOT_FOUND;
848 }
849
850 /* Compare given item and item pointed to by the path. */
851 int comp_items(const struct item_head *stored_ih, const struct treepath *p_s_path)
852 {
853         struct buffer_head *bh = PATH_PLAST_BUFFER(p_s_path);
854         struct item_head *ih;
855
856         /* Last buffer at the path is not in the tree. */
857         if (!B_IS_IN_TREE(bh))
858                 return 1;
859
860         /* Last path position is invalid. */
861         if (PATH_LAST_POSITION(p_s_path) >= B_NR_ITEMS(bh))
862                 return 1;
863
864         /* we need only to know, whether it is the same item */
865         ih = get_ih(p_s_path);
866         return memcmp(stored_ih, ih, IH_SIZE);
867 }
868
869 /* unformatted nodes are not logged anymore, ever.  This is safe
870 ** now
871 */
872 #define held_by_others(bh) (atomic_read(&(bh)->b_count) > 1)
873
874 // block can not be forgotten as it is in I/O or held by someone
875 #define block_in_use(bh) (buffer_locked(bh) || (held_by_others(bh)))
876
877 // prepare for delete or cut of direct item
878 static inline int prepare_for_direct_item(struct treepath *path,
879                                           struct item_head *le_ih,
880                                           struct inode *inode,
881                                           loff_t new_file_length, int *cut_size)
882 {
883         loff_t round_len;
884
885         if (new_file_length == max_reiserfs_offset(inode)) {
886                 /* item has to be deleted */
887                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
888                 return M_DELETE;
889         }
890         // new file gets truncated
891         if (get_inode_item_key_version(inode) == KEY_FORMAT_3_6) {
892                 //
893                 round_len = ROUND_UP(new_file_length);
894                 /* this was n_new_file_length < le_ih ... */
895                 if (round_len < le_ih_k_offset(le_ih)) {
896                         *cut_size = -(IH_SIZE + ih_item_len(le_ih));
897                         return M_DELETE;        /* Delete this item. */
898                 }
899                 /* Calculate first position and size for cutting from item. */
900                 pos_in_item(path) = round_len - (le_ih_k_offset(le_ih) - 1);
901                 *cut_size = -(ih_item_len(le_ih) - pos_in_item(path));
902
903                 return M_CUT;   /* Cut from this item. */
904         }
905
906         // old file: items may have any length
907
908         if (new_file_length < le_ih_k_offset(le_ih)) {
909                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
910                 return M_DELETE;        /* Delete this item. */
911         }
912         /* Calculate first position and size for cutting from item. */
913         *cut_size = -(ih_item_len(le_ih) -
914                       (pos_in_item(path) =
915                        new_file_length + 1 - le_ih_k_offset(le_ih)));
916         return M_CUT;           /* Cut from this item. */
917 }
918
919 static inline int prepare_for_direntry_item(struct treepath *path,
920                                             struct item_head *le_ih,
921                                             struct inode *inode,
922                                             loff_t new_file_length,
923                                             int *cut_size)
924 {
925         if (le_ih_k_offset(le_ih) == DOT_OFFSET &&
926             new_file_length == max_reiserfs_offset(inode)) {
927                 RFALSE(ih_entry_count(le_ih) != 2,
928                        "PAP-5220: incorrect empty directory item (%h)", le_ih);
929                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
930                 return M_DELETE;        /* Delete the directory item containing "." and ".." entry. */
931         }
932
933         if (ih_entry_count(le_ih) == 1) {
934                 /* Delete the directory item such as there is one record only
935                    in this item */
936                 *cut_size = -(IH_SIZE + ih_item_len(le_ih));
937                 return M_DELETE;
938         }
939
940         /* Cut one record from the directory item. */
941         *cut_size =
942             -(DEH_SIZE +
943               entry_length(get_last_bh(path), le_ih, pos_in_item(path)));
944         return M_CUT;
945 }
946
947 #define JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD (2 * JOURNAL_PER_BALANCE_CNT + 1)
948
949 /*  If the path points to a directory or direct item, calculate mode and the size cut, for balance.
950     If the path points to an indirect item, remove some number of its unformatted nodes.
951     In case of file truncate calculate whether this item must be deleted/truncated or last
952     unformatted node of this item will be converted to a direct item.
953     This function returns a determination of what balance mode the calling function should employ. */
954 static char prepare_for_delete_or_cut(struct reiserfs_transaction_handle *th, struct inode *inode, struct treepath *p_s_path, const struct cpu_key *p_s_item_key, int *p_n_removed,     /* Number of unformatted nodes which were removed
955                                                                                                                                                                                    from end of the file. */
956                                       int *p_n_cut_size, unsigned long long n_new_file_length   /* MAX_KEY_OFFSET in case of delete. */
957     )
958 {
959         struct super_block *sb = inode->i_sb;
960         struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_path);
961         struct buffer_head *bh = PATH_PLAST_BUFFER(p_s_path);
962
963         BUG_ON(!th->t_trans_id);
964
965         /* Stat_data item. */
966         if (is_statdata_le_ih(p_le_ih)) {
967
968                 RFALSE(n_new_file_length != max_reiserfs_offset(inode),
969                        "PAP-5210: mode must be M_DELETE");
970
971                 *p_n_cut_size = -(IH_SIZE + ih_item_len(p_le_ih));
972                 return M_DELETE;
973         }
974
975         /* Directory item. */
976         if (is_direntry_le_ih(p_le_ih))
977                 return prepare_for_direntry_item(p_s_path, p_le_ih, inode,
978                                                  n_new_file_length,
979                                                  p_n_cut_size);
980
981         /* Direct item. */
982         if (is_direct_le_ih(p_le_ih))
983                 return prepare_for_direct_item(p_s_path, p_le_ih, inode,
984                                                n_new_file_length, p_n_cut_size);
985
986         /* Case of an indirect item. */
987         {
988             int blk_size = sb->s_blocksize;
989             struct item_head s_ih;
990             int need_re_search;
991             int delete = 0;
992             int result = M_CUT;
993             int pos = 0;
994
995             if ( n_new_file_length == max_reiserfs_offset (inode) ) {
996                 /* prepare_for_delete_or_cut() is called by
997                  * reiserfs_delete_item() */
998                 n_new_file_length = 0;
999                 delete = 1;
1000             }
1001
1002             do {
1003                 need_re_search = 0;
1004                 *p_n_cut_size = 0;
1005                 bh = PATH_PLAST_BUFFER(p_s_path);
1006                 copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
1007                 pos = I_UNFM_NUM(&s_ih);
1008
1009                 while (le_ih_k_offset (&s_ih) + (pos - 1) * blk_size > n_new_file_length) {
1010                     __le32 *unfm;
1011                     __u32 block;
1012
1013                     /* Each unformatted block deletion may involve one additional
1014                      * bitmap block into the transaction, thereby the initial
1015                      * journal space reservation might not be enough. */
1016                     if (!delete && (*p_n_cut_size) != 0 &&
1017                         reiserfs_transaction_free_space(th) < JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) {
1018                         break;
1019                     }
1020
1021                     unfm = (__le32 *)B_I_PITEM(bh, &s_ih) + pos - 1;
1022                     block = get_block_num(unfm, 0);
1023
1024                     if (block != 0) {
1025                         reiserfs_prepare_for_journal(sb, bh, 1);
1026                         put_block_num(unfm, 0, 0);
1027                         journal_mark_dirty(th, sb, bh);
1028                         reiserfs_free_block(th, inode, block, 1);
1029                     }
1030
1031                     cond_resched();
1032
1033                     if (item_moved (&s_ih, p_s_path))  {
1034                         need_re_search = 1;
1035                         break;
1036                     }
1037
1038                     pos --;
1039                     (*p_n_removed) ++;
1040                     (*p_n_cut_size) -= UNFM_P_SIZE;
1041
1042                     if (pos == 0) {
1043                         (*p_n_cut_size) -= IH_SIZE;
1044                         result = M_DELETE;
1045                         break;
1046                     }
1047                 }
1048                 /* a trick.  If the buffer has been logged, this will do nothing.  If
1049                 ** we've broken the loop without logging it, it will restore the
1050                 ** buffer */
1051                 reiserfs_restore_prepared_buffer(sb, bh);
1052             } while (need_re_search &&
1053                      search_for_position_by_key(sb, p_s_item_key, p_s_path) == POSITION_FOUND);
1054             pos_in_item(p_s_path) = pos * UNFM_P_SIZE;
1055
1056             if (*p_n_cut_size == 0) {
1057                 /* Nothing were cut. maybe convert last unformatted node to the
1058                  * direct item? */
1059                 result = M_CONVERT;
1060             }
1061             return result;
1062         }
1063 }
1064
1065 /* Calculate number of bytes which will be deleted or cut during balance */
1066 static int calc_deleted_bytes_number(struct tree_balance *p_s_tb, char c_mode)
1067 {
1068         int n_del_size;
1069         struct item_head *p_le_ih = PATH_PITEM_HEAD(p_s_tb->tb_path);
1070
1071         if (is_statdata_le_ih(p_le_ih))
1072                 return 0;
1073
1074         n_del_size =
1075             (c_mode ==
1076              M_DELETE) ? ih_item_len(p_le_ih) : -p_s_tb->insert_size[0];
1077         if (is_direntry_le_ih(p_le_ih)) {
1078                 // return EMPTY_DIR_SIZE; /* We delete emty directoris only. */
1079                 // we can't use EMPTY_DIR_SIZE, as old format dirs have a different
1080                 // empty size.  ick. FIXME, is this right?
1081                 //
1082                 return n_del_size;
1083         }
1084
1085         if (is_indirect_le_ih(p_le_ih))
1086                 n_del_size = (n_del_size / UNFM_P_SIZE) * (PATH_PLAST_BUFFER(p_s_tb->tb_path)->b_size); // - get_ih_free_space (p_le_ih);
1087         return n_del_size;
1088 }
1089
1090 static void init_tb_struct(struct reiserfs_transaction_handle *th,
1091                            struct tree_balance *p_s_tb,
1092                            struct super_block *sb,
1093                            struct treepath *p_s_path, int n_size)
1094 {
1095
1096         BUG_ON(!th->t_trans_id);
1097
1098         memset(p_s_tb, '\0', sizeof(struct tree_balance));
1099         p_s_tb->transaction_handle = th;
1100         p_s_tb->tb_sb = sb;
1101         p_s_tb->tb_path = p_s_path;
1102         PATH_OFFSET_PBUFFER(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = NULL;
1103         PATH_OFFSET_POSITION(p_s_path, ILLEGAL_PATH_ELEMENT_OFFSET) = 0;
1104         p_s_tb->insert_size[0] = n_size;
1105 }
1106
1107 void padd_item(char *item, int total_length, int length)
1108 {
1109         int i;
1110
1111         for (i = total_length; i > length;)
1112                 item[--i] = 0;
1113 }
1114
1115 #ifdef REISERQUOTA_DEBUG
1116 char key2type(struct reiserfs_key *ih)
1117 {
1118         if (is_direntry_le_key(2, ih))
1119                 return 'd';
1120         if (is_direct_le_key(2, ih))
1121                 return 'D';
1122         if (is_indirect_le_key(2, ih))
1123                 return 'i';
1124         if (is_statdata_le_key(2, ih))
1125                 return 's';
1126         return 'u';
1127 }
1128
1129 char head2type(struct item_head *ih)
1130 {
1131         if (is_direntry_le_ih(ih))
1132                 return 'd';
1133         if (is_direct_le_ih(ih))
1134                 return 'D';
1135         if (is_indirect_le_ih(ih))
1136                 return 'i';
1137         if (is_statdata_le_ih(ih))
1138                 return 's';
1139         return 'u';
1140 }
1141 #endif
1142
1143 /* Delete object item. */
1144 int reiserfs_delete_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_path,     /* Path to the deleted item. */
1145                          const struct cpu_key *p_s_item_key,    /* Key to search for the deleted item.  */
1146                          struct inode *inode,   /* inode is here just to update
1147                                                  * i_blocks and quotas */
1148                          struct buffer_head *p_s_un_bh)
1149 {                               /* NULL or unformatted node pointer.    */
1150         struct super_block *sb = inode->i_sb;
1151         struct tree_balance s_del_balance;
1152         struct item_head s_ih;
1153         struct item_head *q_ih;
1154         int quota_cut_bytes;
1155         int n_ret_value, n_del_size, n_removed;
1156
1157 #ifdef CONFIG_REISERFS_CHECK
1158         char c_mode;
1159         int n_iter = 0;
1160 #endif
1161
1162         BUG_ON(!th->t_trans_id);
1163
1164         init_tb_struct(th, &s_del_balance, sb, p_s_path,
1165                        0 /*size is unknown */ );
1166
1167         while (1) {
1168                 n_removed = 0;
1169
1170 #ifdef CONFIG_REISERFS_CHECK
1171                 n_iter++;
1172                 c_mode =
1173 #endif
1174                     prepare_for_delete_or_cut(th, inode, p_s_path,
1175                                               p_s_item_key, &n_removed,
1176                                               &n_del_size,
1177                                               max_reiserfs_offset(inode));
1178
1179                 RFALSE(c_mode != M_DELETE, "PAP-5320: mode must be M_DELETE");
1180
1181                 copy_item_head(&s_ih, PATH_PITEM_HEAD(p_s_path));
1182                 s_del_balance.insert_size[0] = n_del_size;
1183
1184                 n_ret_value = fix_nodes(M_DELETE, &s_del_balance, NULL, NULL);
1185                 if (n_ret_value != REPEAT_SEARCH)
1186                         break;
1187
1188                 PROC_INFO_INC(sb, delete_item_restarted);
1189
1190                 // file system changed, repeat search
1191                 n_ret_value =
1192                     search_for_position_by_key(sb, p_s_item_key, p_s_path);
1193                 if (n_ret_value == IO_ERROR)
1194                         break;
1195                 if (n_ret_value == FILE_NOT_FOUND) {
1196                         reiserfs_warning(sb, "vs-5340",
1197                                          "no items of the file %K found",
1198                                          p_s_item_key);
1199                         break;
1200                 }
1201         }                       /* while (1) */
1202
1203         if (n_ret_value != CARRY_ON) {
1204                 unfix_nodes(&s_del_balance);
1205                 return 0;
1206         }
1207         // reiserfs_delete_item returns item length when success
1208         n_ret_value = calc_deleted_bytes_number(&s_del_balance, M_DELETE);
1209         q_ih = get_ih(p_s_path);
1210         quota_cut_bytes = ih_item_len(q_ih);
1211
1212         /* hack so the quota code doesn't have to guess if the file
1213          ** has a tail.  On tail insert, we allocate quota for 1 unformatted node.
1214          ** We test the offset because the tail might have been
1215          ** split into multiple items, and we only want to decrement for
1216          ** the unfm node once
1217          */
1218         if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(q_ih)) {
1219                 if ((le_ih_k_offset(q_ih) & (sb->s_blocksize - 1)) == 1) {
1220                         quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE;
1221                 } else {
1222                         quota_cut_bytes = 0;
1223                 }
1224         }
1225
1226         if (p_s_un_bh) {
1227                 int off;
1228                 char *data;
1229
1230                 /* We are in direct2indirect conversion, so move tail contents
1231                    to the unformatted node */
1232                 /* note, we do the copy before preparing the buffer because we
1233                  ** don't care about the contents of the unformatted node yet.
1234                  ** the only thing we really care about is the direct item's data
1235                  ** is in the unformatted node.
1236                  **
1237                  ** Otherwise, we would have to call reiserfs_prepare_for_journal on
1238                  ** the unformatted node, which might schedule, meaning we'd have to
1239                  ** loop all the way back up to the start of the while loop.
1240                  **
1241                  ** The unformatted node must be dirtied later on.  We can't be
1242                  ** sure here if the entire tail has been deleted yet.
1243                  **
1244                  ** p_s_un_bh is from the page cache (all unformatted nodes are
1245                  ** from the page cache) and might be a highmem page.  So, we
1246                  ** can't use p_s_un_bh->b_data.
1247                  ** -clm
1248                  */
1249
1250                 data = kmap_atomic(p_s_un_bh->b_page, KM_USER0);
1251                 off = ((le_ih_k_offset(&s_ih) - 1) & (PAGE_CACHE_SIZE - 1));
1252                 memcpy(data + off,
1253                        B_I_PITEM(PATH_PLAST_BUFFER(p_s_path), &s_ih),
1254                        n_ret_value);
1255                 kunmap_atomic(data, KM_USER0);
1256         }
1257         /* Perform balancing after all resources have been collected at once. */
1258         do_balance(&s_del_balance, NULL, NULL, M_DELETE);
1259
1260 #ifdef REISERQUOTA_DEBUG
1261         reiserfs_debug(sb, REISERFS_DEBUG_CODE,
1262                        "reiserquota delete_item(): freeing %u, id=%u type=%c",
1263                        quota_cut_bytes, inode->i_uid, head2type(&s_ih));
1264 #endif
1265         DQUOT_FREE_SPACE_NODIRTY(inode, quota_cut_bytes);
1266
1267         /* Return deleted body length */
1268         return n_ret_value;
1269 }
1270
1271 /* Summary Of Mechanisms For Handling Collisions Between Processes:
1272
1273  deletion of the body of the object is performed by iput(), with the
1274  result that if multiple processes are operating on a file, the
1275  deletion of the body of the file is deferred until the last process
1276  that has an open inode performs its iput().
1277
1278  writes and truncates are protected from collisions by use of
1279  semaphores.
1280
1281  creates, linking, and mknod are protected from collisions with other
1282  processes by making the reiserfs_add_entry() the last step in the
1283  creation, and then rolling back all changes if there was a collision.
1284  - Hans
1285 */
1286
1287 /* this deletes item which never gets split */
1288 void reiserfs_delete_solid_item(struct reiserfs_transaction_handle *th,
1289                                 struct inode *inode, struct reiserfs_key *key)
1290 {
1291         struct tree_balance tb;
1292         INITIALIZE_PATH(path);
1293         int item_len = 0;
1294         int tb_init = 0;
1295         struct cpu_key cpu_key;
1296         int retval;
1297         int quota_cut_bytes = 0;
1298
1299         BUG_ON(!th->t_trans_id);
1300
1301         le_key2cpu_key(&cpu_key, key);
1302
1303         while (1) {
1304                 retval = search_item(th->t_super, &cpu_key, &path);
1305                 if (retval == IO_ERROR) {
1306                         reiserfs_error(th->t_super, "vs-5350",
1307                                        "i/o failure occurred trying "
1308                                        "to delete %K", &cpu_key);
1309                         break;
1310                 }
1311                 if (retval != ITEM_FOUND) {
1312                         pathrelse(&path);
1313                         // No need for a warning, if there is just no free space to insert '..' item into the newly-created subdir
1314                         if (!
1315                             ((unsigned long long)
1316                              GET_HASH_VALUE(le_key_k_offset
1317                                             (le_key_version(key), key)) == 0
1318                              && (unsigned long long)
1319                              GET_GENERATION_NUMBER(le_key_k_offset
1320                                                    (le_key_version(key),
1321                                                     key)) == 1))
1322                                 reiserfs_warning(th->t_super, "vs-5355",
1323                                                  "%k not found", key);
1324                         break;
1325                 }
1326                 if (!tb_init) {
1327                         tb_init = 1;
1328                         item_len = ih_item_len(PATH_PITEM_HEAD(&path));
1329                         init_tb_struct(th, &tb, th->t_super, &path,
1330                                        -(IH_SIZE + item_len));
1331                 }
1332                 quota_cut_bytes = ih_item_len(PATH_PITEM_HEAD(&path));
1333
1334                 retval = fix_nodes(M_DELETE, &tb, NULL, NULL);
1335                 if (retval == REPEAT_SEARCH) {
1336                         PROC_INFO_INC(th->t_super, delete_solid_item_restarted);
1337                         continue;
1338                 }
1339
1340                 if (retval == CARRY_ON) {
1341                         do_balance(&tb, NULL, NULL, M_DELETE);
1342                         if (inode) {    /* Should we count quota for item? (we don't count quotas for save-links) */
1343 #ifdef REISERQUOTA_DEBUG
1344                                 reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
1345                                                "reiserquota delete_solid_item(): freeing %u id=%u type=%c",
1346                                                quota_cut_bytes, inode->i_uid,
1347                                                key2type(key));
1348 #endif
1349                                 DQUOT_FREE_SPACE_NODIRTY(inode,
1350                                                          quota_cut_bytes);
1351                         }
1352                         break;
1353                 }
1354                 // IO_ERROR, NO_DISK_SPACE, etc
1355                 reiserfs_warning(th->t_super, "vs-5360",
1356                                  "could not delete %K due to fix_nodes failure",
1357                                  &cpu_key);
1358                 unfix_nodes(&tb);
1359                 break;
1360         }
1361
1362         reiserfs_check_path(&path);
1363 }
1364
1365 int reiserfs_delete_object(struct reiserfs_transaction_handle *th,
1366                            struct inode *inode)
1367 {
1368         int err;
1369         inode->i_size = 0;
1370         BUG_ON(!th->t_trans_id);
1371
1372         /* for directory this deletes item containing "." and ".." */
1373         err =
1374             reiserfs_do_truncate(th, inode, NULL, 0 /*no timestamp updates */ );
1375         if (err)
1376                 return err;
1377
1378 #if defined( USE_INODE_GENERATION_COUNTER )
1379         if (!old_format_only(th->t_super)) {
1380                 __le32 *inode_generation;
1381
1382                 inode_generation =
1383                     &REISERFS_SB(th->t_super)->s_rs->s_inode_generation;
1384                 le32_add_cpu(inode_generation, 1);
1385         }
1386 /* USE_INODE_GENERATION_COUNTER */
1387 #endif
1388         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1389
1390         return err;
1391 }
1392
1393 static void unmap_buffers(struct page *page, loff_t pos)
1394 {
1395         struct buffer_head *bh;
1396         struct buffer_head *head;
1397         struct buffer_head *next;
1398         unsigned long tail_index;
1399         unsigned long cur_index;
1400
1401         if (page) {
1402                 if (page_has_buffers(page)) {
1403                         tail_index = pos & (PAGE_CACHE_SIZE - 1);
1404                         cur_index = 0;
1405                         head = page_buffers(page);
1406                         bh = head;
1407                         do {
1408                                 next = bh->b_this_page;
1409
1410                                 /* we want to unmap the buffers that contain the tail, and
1411                                  ** all the buffers after it (since the tail must be at the
1412                                  ** end of the file).  We don't want to unmap file data
1413                                  ** before the tail, since it might be dirty and waiting to
1414                                  ** reach disk
1415                                  */
1416                                 cur_index += bh->b_size;
1417                                 if (cur_index > tail_index) {
1418                                         reiserfs_unmap_buffer(bh);
1419                                 }
1420                                 bh = next;
1421                         } while (bh != head);
1422                 }
1423         }
1424 }
1425
1426 static int maybe_indirect_to_direct(struct reiserfs_transaction_handle *th,
1427                                     struct inode *inode,
1428                                     struct page *page,
1429                                     struct treepath *p_s_path,
1430                                     const struct cpu_key *p_s_item_key,
1431                                     loff_t n_new_file_size, char *p_c_mode)
1432 {
1433         struct super_block *sb = inode->i_sb;
1434         int n_block_size = sb->s_blocksize;
1435         int cut_bytes;
1436         BUG_ON(!th->t_trans_id);
1437         BUG_ON(n_new_file_size != inode->i_size);
1438
1439         /* the page being sent in could be NULL if there was an i/o error
1440          ** reading in the last block.  The user will hit problems trying to
1441          ** read the file, but for now we just skip the indirect2direct
1442          */
1443         if (atomic_read(&inode->i_count) > 1 ||
1444             !tail_has_to_be_packed(inode) ||
1445             !page || (REISERFS_I(inode)->i_flags & i_nopack_mask)) {
1446                 /* leave tail in an unformatted node */
1447                 *p_c_mode = M_SKIP_BALANCING;
1448                 cut_bytes =
1449                     n_block_size - (n_new_file_size & (n_block_size - 1));
1450                 pathrelse(p_s_path);
1451                 return cut_bytes;
1452         }
1453         /* Permorm the conversion to a direct_item. */
1454         /* return indirect_to_direct(inode, p_s_path, p_s_item_key,
1455                                   n_new_file_size, p_c_mode); */
1456         return indirect2direct(th, inode, page, p_s_path, p_s_item_key,
1457                                n_new_file_size, p_c_mode);
1458 }
1459
1460 /* we did indirect_to_direct conversion. And we have inserted direct
1461    item successesfully, but there were no disk space to cut unfm
1462    pointer being converted. Therefore we have to delete inserted
1463    direct item(s) */
1464 static void indirect_to_direct_roll_back(struct reiserfs_transaction_handle *th,
1465                                          struct inode *inode, struct treepath *path)
1466 {
1467         struct cpu_key tail_key;
1468         int tail_len;
1469         int removed;
1470         BUG_ON(!th->t_trans_id);
1471
1472         make_cpu_key(&tail_key, inode, inode->i_size + 1, TYPE_DIRECT, 4);      // !!!!
1473         tail_key.key_length = 4;
1474
1475         tail_len =
1476             (cpu_key_k_offset(&tail_key) & (inode->i_sb->s_blocksize - 1)) - 1;
1477         while (tail_len) {
1478                 /* look for the last byte of the tail */
1479                 if (search_for_position_by_key(inode->i_sb, &tail_key, path) ==
1480                     POSITION_NOT_FOUND)
1481                         reiserfs_panic(inode->i_sb, "vs-5615",
1482                                        "found invalid item");
1483                 RFALSE(path->pos_in_item !=
1484                        ih_item_len(PATH_PITEM_HEAD(path)) - 1,
1485                        "vs-5616: appended bytes found");
1486                 PATH_LAST_POSITION(path)--;
1487
1488                 removed =
1489                     reiserfs_delete_item(th, path, &tail_key, inode,
1490                                          NULL /*unbh not needed */ );
1491                 RFALSE(removed <= 0
1492                        || removed > tail_len,
1493                        "vs-5617: there was tail %d bytes, removed item length %d bytes",
1494                        tail_len, removed);
1495                 tail_len -= removed;
1496                 set_cpu_key_k_offset(&tail_key,
1497                                      cpu_key_k_offset(&tail_key) - removed);
1498         }
1499         reiserfs_warning(inode->i_sb, "reiserfs-5091", "indirect_to_direct "
1500                          "conversion has been rolled back due to "
1501                          "lack of disk space");
1502         //mark_file_without_tail (inode);
1503         mark_inode_dirty(inode);
1504 }
1505
1506 /* (Truncate or cut entry) or delete object item. Returns < 0 on failure */
1507 int reiserfs_cut_from_item(struct reiserfs_transaction_handle *th,
1508                            struct treepath *p_s_path,
1509                            struct cpu_key *p_s_item_key,
1510                            struct inode *inode,
1511                            struct page *page, loff_t n_new_file_size)
1512 {
1513         struct super_block *sb = inode->i_sb;
1514         /* Every function which is going to call do_balance must first
1515            create a tree_balance structure.  Then it must fill up this
1516            structure by using the init_tb_struct and fix_nodes functions.
1517            After that we can make tree balancing. */
1518         struct tree_balance s_cut_balance;
1519         struct item_head *p_le_ih;
1520         int n_cut_size = 0,     /* Amount to be cut. */
1521             n_ret_value = CARRY_ON, n_removed = 0,      /* Number of the removed unformatted nodes. */
1522             n_is_inode_locked = 0;
1523         char c_mode;            /* Mode of the balance. */
1524         int retval2 = -1;
1525         int quota_cut_bytes;
1526         loff_t tail_pos = 0;
1527
1528         BUG_ON(!th->t_trans_id);
1529
1530         init_tb_struct(th, &s_cut_balance, inode->i_sb, p_s_path,
1531                        n_cut_size);
1532
1533         /* Repeat this loop until we either cut the item without needing
1534            to balance, or we fix_nodes without schedule occurring */
1535         while (1) {
1536                 /* Determine the balance mode, position of the first byte to
1537                    be cut, and size to be cut.  In case of the indirect item
1538                    free unformatted nodes which are pointed to by the cut
1539                    pointers. */
1540
1541                 c_mode =
1542                     prepare_for_delete_or_cut(th, inode, p_s_path,
1543                                               p_s_item_key, &n_removed,
1544                                               &n_cut_size, n_new_file_size);
1545                 if (c_mode == M_CONVERT) {
1546                         /* convert last unformatted node to direct item or leave
1547                            tail in the unformatted node */
1548                         RFALSE(n_ret_value != CARRY_ON,
1549                                "PAP-5570: can not convert twice");
1550
1551                         n_ret_value =
1552                             maybe_indirect_to_direct(th, inode, page,
1553                                                      p_s_path, p_s_item_key,
1554                                                      n_new_file_size, &c_mode);
1555                         if (c_mode == M_SKIP_BALANCING)
1556                                 /* tail has been left in the unformatted node */
1557                                 return n_ret_value;
1558
1559                         n_is_inode_locked = 1;
1560
1561                         /* removing of last unformatted node will change value we
1562                            have to return to truncate. Save it */
1563                         retval2 = n_ret_value;
1564                         /*retval2 = sb->s_blocksize - (n_new_file_size & (sb->s_blocksize - 1)); */
1565
1566                         /* So, we have performed the first part of the conversion:
1567                            inserting the new direct item.  Now we are removing the
1568                            last unformatted node pointer. Set key to search for
1569                            it. */
1570                         set_cpu_key_k_type(p_s_item_key, TYPE_INDIRECT);
1571                         p_s_item_key->key_length = 4;
1572                         n_new_file_size -=
1573                             (n_new_file_size & (sb->s_blocksize - 1));
1574                         tail_pos = n_new_file_size;
1575                         set_cpu_key_k_offset(p_s_item_key, n_new_file_size + 1);
1576                         if (search_for_position_by_key
1577                             (sb, p_s_item_key,
1578                              p_s_path) == POSITION_NOT_FOUND) {
1579                                 print_block(PATH_PLAST_BUFFER(p_s_path), 3,
1580                                             PATH_LAST_POSITION(p_s_path) - 1,
1581                                             PATH_LAST_POSITION(p_s_path) + 1);
1582                                 reiserfs_panic(sb, "PAP-5580", "item to "
1583                                                "convert does not exist (%K)",
1584                                                p_s_item_key);
1585                         }
1586                         continue;
1587                 }
1588                 if (n_cut_size == 0) {
1589                         pathrelse(p_s_path);
1590                         return 0;
1591                 }
1592
1593                 s_cut_balance.insert_size[0] = n_cut_size;
1594
1595                 n_ret_value = fix_nodes(c_mode, &s_cut_balance, NULL, NULL);
1596                 if (n_ret_value != REPEAT_SEARCH)
1597                         break;
1598
1599                 PROC_INFO_INC(sb, cut_from_item_restarted);
1600
1601                 n_ret_value =
1602                     search_for_position_by_key(sb, p_s_item_key, p_s_path);
1603                 if (n_ret_value == POSITION_FOUND)
1604                         continue;
1605
1606                 reiserfs_warning(sb, "PAP-5610", "item %K not found",
1607                                  p_s_item_key);
1608                 unfix_nodes(&s_cut_balance);
1609                 return (n_ret_value == IO_ERROR) ? -EIO : -ENOENT;
1610         }                       /* while */
1611
1612         // check fix_nodes results (IO_ERROR or NO_DISK_SPACE)
1613         if (n_ret_value != CARRY_ON) {
1614                 if (n_is_inode_locked) {
1615                         // FIXME: this seems to be not needed: we are always able
1616                         // to cut item
1617                         indirect_to_direct_roll_back(th, inode, p_s_path);
1618                 }
1619                 if (n_ret_value == NO_DISK_SPACE)
1620                         reiserfs_warning(sb, "reiserfs-5092",
1621                                          "NO_DISK_SPACE");
1622                 unfix_nodes(&s_cut_balance);
1623                 return -EIO;
1624         }
1625
1626         /* go ahead and perform balancing */
1627
1628         RFALSE(c_mode == M_PASTE || c_mode == M_INSERT, "invalid mode");
1629
1630         /* Calculate number of bytes that need to be cut from the item. */
1631         quota_cut_bytes =
1632             (c_mode ==
1633              M_DELETE) ? ih_item_len(get_ih(p_s_path)) : -s_cut_balance.
1634             insert_size[0];
1635         if (retval2 == -1)
1636                 n_ret_value = calc_deleted_bytes_number(&s_cut_balance, c_mode);
1637         else
1638                 n_ret_value = retval2;
1639
1640         /* For direct items, we only change the quota when deleting the last
1641          ** item.
1642          */
1643         p_le_ih = PATH_PITEM_HEAD(s_cut_balance.tb_path);
1644         if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_le_ih)) {
1645                 if (c_mode == M_DELETE &&
1646                     (le_ih_k_offset(p_le_ih) & (sb->s_blocksize - 1)) ==
1647                     1) {
1648                         // FIXME: this is to keep 3.5 happy
1649                         REISERFS_I(inode)->i_first_direct_byte = U32_MAX;
1650                         quota_cut_bytes = sb->s_blocksize + UNFM_P_SIZE;
1651                 } else {
1652                         quota_cut_bytes = 0;
1653                 }
1654         }
1655 #ifdef CONFIG_REISERFS_CHECK
1656         if (n_is_inode_locked) {
1657                 struct item_head *le_ih =
1658                     PATH_PITEM_HEAD(s_cut_balance.tb_path);
1659                 /* we are going to complete indirect2direct conversion. Make
1660                    sure, that we exactly remove last unformatted node pointer
1661                    of the item */
1662                 if (!is_indirect_le_ih(le_ih))
1663                         reiserfs_panic(sb, "vs-5652",
1664                                        "item must be indirect %h", le_ih);
1665
1666                 if (c_mode == M_DELETE && ih_item_len(le_ih) != UNFM_P_SIZE)
1667                         reiserfs_panic(sb, "vs-5653", "completing "
1668                                        "indirect2direct conversion indirect "
1669                                        "item %h being deleted must be of "
1670                                        "4 byte long", le_ih);
1671
1672                 if (c_mode == M_CUT
1673                     && s_cut_balance.insert_size[0] != -UNFM_P_SIZE) {
1674                         reiserfs_panic(sb, "vs-5654", "can not complete "
1675                                        "indirect2direct conversion of %h "
1676                                        "(CUT, insert_size==%d)",
1677                                        le_ih, s_cut_balance.insert_size[0]);
1678                 }
1679                 /* it would be useful to make sure, that right neighboring
1680                    item is direct item of this file */
1681         }
1682 #endif
1683
1684         do_balance(&s_cut_balance, NULL, NULL, c_mode);
1685         if (n_is_inode_locked) {
1686                 /* we've done an indirect->direct conversion.  when the data block
1687                  ** was freed, it was removed from the list of blocks that must
1688                  ** be flushed before the transaction commits, make sure to
1689                  ** unmap and invalidate it
1690                  */
1691                 unmap_buffers(page, tail_pos);
1692                 REISERFS_I(inode)->i_flags &= ~i_pack_on_close_mask;
1693         }
1694 #ifdef REISERQUOTA_DEBUG
1695         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
1696                        "reiserquota cut_from_item(): freeing %u id=%u type=%c",
1697                        quota_cut_bytes, inode->i_uid, '?');
1698 #endif
1699         DQUOT_FREE_SPACE_NODIRTY(inode, quota_cut_bytes);
1700         return n_ret_value;
1701 }
1702
1703 static void truncate_directory(struct reiserfs_transaction_handle *th,
1704                                struct inode *inode)
1705 {
1706         BUG_ON(!th->t_trans_id);
1707         if (inode->i_nlink)
1708                 reiserfs_error(inode->i_sb, "vs-5655", "link count != 0");
1709
1710         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), DOT_OFFSET);
1711         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_DIRENTRY);
1712         reiserfs_delete_solid_item(th, inode, INODE_PKEY(inode));
1713         reiserfs_update_sd(th, inode);
1714         set_le_key_k_offset(KEY_FORMAT_3_5, INODE_PKEY(inode), SD_OFFSET);
1715         set_le_key_k_type(KEY_FORMAT_3_5, INODE_PKEY(inode), TYPE_STAT_DATA);
1716 }
1717
1718 /* Truncate file to the new size. Note, this must be called with a transaction
1719    already started */
1720 int reiserfs_do_truncate(struct reiserfs_transaction_handle *th,
1721                           struct inode *inode,  /* ->i_size contains new size */
1722                          struct page *page,     /* up to date for last block */
1723                          int update_timestamps  /* when it is called by
1724                                                    file_release to convert
1725                                                    the tail - no timestamps
1726                                                    should be updated */
1727     )
1728 {
1729         INITIALIZE_PATH(s_search_path); /* Path to the current object item. */
1730         struct item_head *p_le_ih;      /* Pointer to an item header. */
1731         struct cpu_key s_item_key;      /* Key to search for a previous file item. */
1732         loff_t n_file_size,     /* Old file size. */
1733          n_new_file_size;       /* New file size. */
1734         int n_deleted;          /* Number of deleted or truncated bytes. */
1735         int retval;
1736         int err = 0;
1737
1738         BUG_ON(!th->t_trans_id);
1739         if (!
1740             (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
1741              || S_ISLNK(inode->i_mode)))
1742                 return 0;
1743
1744         if (S_ISDIR(inode->i_mode)) {
1745                 // deletion of directory - no need to update timestamps
1746                 truncate_directory(th, inode);
1747                 return 0;
1748         }
1749
1750         /* Get new file size. */
1751         n_new_file_size = inode->i_size;
1752
1753         // FIXME: note, that key type is unimportant here
1754         make_cpu_key(&s_item_key, inode, max_reiserfs_offset(inode),
1755                      TYPE_DIRECT, 3);
1756
1757         retval =
1758             search_for_position_by_key(inode->i_sb, &s_item_key,
1759                                        &s_search_path);
1760         if (retval == IO_ERROR) {
1761                 reiserfs_error(inode->i_sb, "vs-5657",
1762                                "i/o failure occurred trying to truncate %K",
1763                                &s_item_key);
1764                 err = -EIO;
1765                 goto out;
1766         }
1767         if (retval == POSITION_FOUND || retval == FILE_NOT_FOUND) {
1768                 reiserfs_error(inode->i_sb, "PAP-5660",
1769                                "wrong result %d of search for %K", retval,
1770                                &s_item_key);
1771
1772                 err = -EIO;
1773                 goto out;
1774         }
1775
1776         s_search_path.pos_in_item--;
1777
1778         /* Get real file size (total length of all file items) */
1779         p_le_ih = PATH_PITEM_HEAD(&s_search_path);
1780         if (is_statdata_le_ih(p_le_ih))
1781                 n_file_size = 0;
1782         else {
1783                 loff_t offset = le_ih_k_offset(p_le_ih);
1784                 int bytes =
1785                     op_bytes_number(p_le_ih, inode->i_sb->s_blocksize);
1786
1787                 /* this may mismatch with real file size: if last direct item
1788                    had no padding zeros and last unformatted node had no free
1789                    space, this file would have this file size */
1790                 n_file_size = offset + bytes - 1;
1791         }
1792         /*
1793          * are we doing a full truncate or delete, if so
1794          * kick in the reada code
1795          */
1796         if (n_new_file_size == 0)
1797                 s_search_path.reada = PATH_READA | PATH_READA_BACK;
1798
1799         if (n_file_size == 0 || n_file_size < n_new_file_size) {
1800                 goto update_and_out;
1801         }
1802
1803         /* Update key to search for the last file item. */
1804         set_cpu_key_k_offset(&s_item_key, n_file_size);
1805
1806         do {
1807                 /* Cut or delete file item. */
1808                 n_deleted =
1809                     reiserfs_cut_from_item(th, &s_search_path, &s_item_key,
1810                                            inode, page, n_new_file_size);
1811                 if (n_deleted < 0) {
1812                         reiserfs_warning(inode->i_sb, "vs-5665",
1813                                          "reiserfs_cut_from_item failed");
1814                         reiserfs_check_path(&s_search_path);
1815                         return 0;
1816                 }
1817
1818                 RFALSE(n_deleted > n_file_size,
1819                        "PAP-5670: reiserfs_cut_from_item: too many bytes deleted: deleted %d, file_size %lu, item_key %K",
1820                        n_deleted, n_file_size, &s_item_key);
1821
1822                 /* Change key to search the last file item. */
1823                 n_file_size -= n_deleted;
1824
1825                 set_cpu_key_k_offset(&s_item_key, n_file_size);
1826
1827                 /* While there are bytes to truncate and previous file item is presented in the tree. */
1828
1829                 /*
1830                  ** This loop could take a really long time, and could log
1831                  ** many more blocks than a transaction can hold.  So, we do a polite
1832                  ** journal end here, and if the transaction needs ending, we make
1833                  ** sure the file is consistent before ending the current trans
1834                  ** and starting a new one
1835                  */
1836                 if (journal_transaction_should_end(th, 0) ||
1837                     reiserfs_transaction_free_space(th) <= JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD) {
1838                         int orig_len_alloc = th->t_blocks_allocated;
1839                         pathrelse(&s_search_path);
1840
1841                         if (update_timestamps) {
1842                                 inode->i_mtime = CURRENT_TIME_SEC;
1843                                 inode->i_ctime = CURRENT_TIME_SEC;
1844                         }
1845                         reiserfs_update_sd(th, inode);
1846
1847                         err = journal_end(th, inode->i_sb, orig_len_alloc);
1848                         if (err)
1849                                 goto out;
1850                         err = journal_begin(th, inode->i_sb,
1851                                             JOURNAL_FOR_FREE_BLOCK_AND_UPDATE_SD + JOURNAL_PER_BALANCE_CNT * 4) ;
1852                         if (err)
1853                                 goto out;
1854                         reiserfs_update_inode_transaction(inode);
1855                 }
1856         } while (n_file_size > ROUND_UP(n_new_file_size) &&
1857                  search_for_position_by_key(inode->i_sb, &s_item_key,
1858                                             &s_search_path) == POSITION_FOUND);
1859
1860         RFALSE(n_file_size > ROUND_UP(n_new_file_size),
1861                "PAP-5680: truncate did not finish: new_file_size %Ld, current %Ld, oid %d",
1862                n_new_file_size, n_file_size, s_item_key.on_disk_key.k_objectid);
1863
1864       update_and_out:
1865         if (update_timestamps) {
1866                 // this is truncate, not file closing
1867                 inode->i_mtime = CURRENT_TIME_SEC;
1868                 inode->i_ctime = CURRENT_TIME_SEC;
1869         }
1870         reiserfs_update_sd(th, inode);
1871
1872       out:
1873         pathrelse(&s_search_path);
1874         return err;
1875 }
1876
1877 #ifdef CONFIG_REISERFS_CHECK
1878 // this makes sure, that we __append__, not overwrite or add holes
1879 static void check_research_for_paste(struct treepath *path,
1880                                      const struct cpu_key *p_s_key)
1881 {
1882         struct item_head *found_ih = get_ih(path);
1883
1884         if (is_direct_le_ih(found_ih)) {
1885                 if (le_ih_k_offset(found_ih) +
1886                     op_bytes_number(found_ih,
1887                                     get_last_bh(path)->b_size) !=
1888                     cpu_key_k_offset(p_s_key)
1889                     || op_bytes_number(found_ih,
1890                                        get_last_bh(path)->b_size) !=
1891                     pos_in_item(path))
1892                         reiserfs_panic(NULL, "PAP-5720", "found direct item "
1893                                        "%h or position (%d) does not match "
1894                                        "to key %K", found_ih,
1895                                        pos_in_item(path), p_s_key);
1896         }
1897         if (is_indirect_le_ih(found_ih)) {
1898                 if (le_ih_k_offset(found_ih) +
1899                     op_bytes_number(found_ih,
1900                                     get_last_bh(path)->b_size) !=
1901                     cpu_key_k_offset(p_s_key)
1902                     || I_UNFM_NUM(found_ih) != pos_in_item(path)
1903                     || get_ih_free_space(found_ih) != 0)
1904                         reiserfs_panic(NULL, "PAP-5730", "found indirect "
1905                                        "item (%h) or position (%d) does not "
1906                                        "match to key (%K)",
1907                                        found_ih, pos_in_item(path), p_s_key);
1908         }
1909 }
1910 #endif                          /* config reiserfs check */
1911
1912 /* Paste bytes to the existing item. Returns bytes number pasted into the item. */
1913 int reiserfs_paste_into_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_search_path,  /* Path to the pasted item.          */
1914                              const struct cpu_key *p_s_key,     /* Key to search for the needed item. */
1915                              struct inode *inode,       /* Inode item belongs to */
1916                              const char *p_c_body,      /* Pointer to the bytes to paste.    */
1917                              int n_pasted_size)
1918 {                               /* Size of pasted bytes.             */
1919         struct tree_balance s_paste_balance;
1920         int retval;
1921         int fs_gen;
1922
1923         BUG_ON(!th->t_trans_id);
1924
1925         fs_gen = get_generation(inode->i_sb);
1926
1927 #ifdef REISERQUOTA_DEBUG
1928         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
1929                        "reiserquota paste_into_item(): allocating %u id=%u type=%c",
1930                        n_pasted_size, inode->i_uid,
1931                        key2type(&(p_s_key->on_disk_key)));
1932 #endif
1933
1934         if (DQUOT_ALLOC_SPACE_NODIRTY(inode, n_pasted_size)) {
1935                 pathrelse(p_s_search_path);
1936                 return -EDQUOT;
1937         }
1938         init_tb_struct(th, &s_paste_balance, th->t_super, p_s_search_path,
1939                        n_pasted_size);
1940 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
1941         s_paste_balance.key = p_s_key->on_disk_key;
1942 #endif
1943
1944         /* DQUOT_* can schedule, must check before the fix_nodes */
1945         if (fs_changed(fs_gen, inode->i_sb)) {
1946                 goto search_again;
1947         }
1948
1949         while ((retval =
1950                 fix_nodes(M_PASTE, &s_paste_balance, NULL,
1951                           p_c_body)) == REPEAT_SEARCH) {
1952               search_again:
1953                 /* file system changed while we were in the fix_nodes */
1954                 PROC_INFO_INC(th->t_super, paste_into_item_restarted);
1955                 retval =
1956                     search_for_position_by_key(th->t_super, p_s_key,
1957                                                p_s_search_path);
1958                 if (retval == IO_ERROR) {
1959                         retval = -EIO;
1960                         goto error_out;
1961                 }
1962                 if (retval == POSITION_FOUND) {
1963                         reiserfs_warning(inode->i_sb, "PAP-5710",
1964                                          "entry or pasted byte (%K) exists",
1965                                          p_s_key);
1966                         retval = -EEXIST;
1967                         goto error_out;
1968                 }
1969 #ifdef CONFIG_REISERFS_CHECK
1970                 check_research_for_paste(p_s_search_path, p_s_key);
1971 #endif
1972         }
1973
1974         /* Perform balancing after all resources are collected by fix_nodes, and
1975            accessing them will not risk triggering schedule. */
1976         if (retval == CARRY_ON) {
1977                 do_balance(&s_paste_balance, NULL /*ih */ , p_c_body, M_PASTE);
1978                 return 0;
1979         }
1980         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
1981       error_out:
1982         /* this also releases the path */
1983         unfix_nodes(&s_paste_balance);
1984 #ifdef REISERQUOTA_DEBUG
1985         reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
1986                        "reiserquota paste_into_item(): freeing %u id=%u type=%c",
1987                        n_pasted_size, inode->i_uid,
1988                        key2type(&(p_s_key->on_disk_key)));
1989 #endif
1990         DQUOT_FREE_SPACE_NODIRTY(inode, n_pasted_size);
1991         return retval;
1992 }
1993
1994 /* Insert new item into the buffer at the path. */
1995 int reiserfs_insert_item(struct reiserfs_transaction_handle *th, struct treepath *p_s_path,     /* Path to the inserteded item.         */
1996                          const struct cpu_key *key, struct item_head *p_s_ih,   /* Pointer to the item header to insert. */
1997                          struct inode *inode, const char *p_c_body)
1998 {                               /* Pointer to the bytes to insert.      */
1999         struct tree_balance s_ins_balance;
2000         int retval;
2001         int fs_gen = 0;
2002         int quota_bytes = 0;
2003
2004         BUG_ON(!th->t_trans_id);
2005
2006         if (inode) {            /* Do we count quotas for item? */
2007                 fs_gen = get_generation(inode->i_sb);
2008                 quota_bytes = ih_item_len(p_s_ih);
2009
2010                 /* hack so the quota code doesn't have to guess if the file has
2011                  ** a tail, links are always tails, so there's no guessing needed
2012                  */
2013                 if (!S_ISLNK(inode->i_mode) && is_direct_le_ih(p_s_ih)) {
2014                         quota_bytes = inode->i_sb->s_blocksize + UNFM_P_SIZE;
2015                 }
2016 #ifdef REISERQUOTA_DEBUG
2017                 reiserfs_debug(inode->i_sb, REISERFS_DEBUG_CODE,
2018                                "reiserquota insert_item(): allocating %u id=%u type=%c",
2019                                quota_bytes, inode->i_uid, head2type(p_s_ih));
2020 #endif
2021                 /* We can't dirty inode here. It would be immediately written but
2022                  * appropriate stat item isn't inserted yet... */
2023                 if (DQUOT_ALLOC_SPACE_NODIRTY(inode, quota_bytes)) {
2024                         pathrelse(p_s_path);
2025                         return -EDQUOT;
2026                 }
2027         }
2028         init_tb_struct(th, &s_ins_balance, th->t_super, p_s_path,
2029                        IH_SIZE + ih_item_len(p_s_ih));
2030 #ifdef DISPLACE_NEW_PACKING_LOCALITIES
2031         s_ins_balance.key = key->on_disk_key;
2032 #endif
2033         /* DQUOT_* can schedule, must check to be sure calling fix_nodes is safe */
2034         if (inode && fs_changed(fs_gen, inode->i_sb)) {
2035                 goto search_again;
2036         }
2037
2038         while ((retval =
2039                 fix_nodes(M_INSERT, &s_ins_balance, p_s_ih,
2040                           p_c_body)) == REPEAT_SEARCH) {
2041               search_again:
2042                 /* file system changed while we were in the fix_nodes */
2043                 PROC_INFO_INC(th->t_super, insert_item_restarted);
2044                 retval = search_item(th->t_super, key, p_s_path);
2045                 if (retval == IO_ERROR) {
2046                         retval = -EIO;
2047                         goto error_out;
2048                 }
2049                 if (retval == ITEM_FOUND) {
2050                         reiserfs_warning(th->t_super, "PAP-5760",
2051                                          "key %K already exists in the tree",
2052                                          key);
2053                         retval = -EEXIST;
2054                         goto error_out;
2055                 }
2056         }
2057
2058         /* make balancing after all resources will be collected at a time */
2059         if (retval == CARRY_ON) {
2060                 do_balance(&s_ins_balance, p_s_ih, p_c_body, M_INSERT);
2061                 return 0;
2062         }
2063
2064         retval = (retval == NO_DISK_SPACE) ? -ENOSPC : -EIO;
2065       error_out:
2066         /* also releases the path */
2067         unfix_nodes(&s_ins_balance);
2068 #ifdef REISERQUOTA_DEBUG
2069         reiserfs_debug(th->t_super, REISERFS_DEBUG_CODE,
2070                        "reiserquota insert_item(): freeing %u id=%u type=%c",
2071                        quota_bytes, inode->i_uid, head2type(p_s_ih));
2072 #endif
2073         if (inode)
2074                 DQUOT_FREE_SPACE_NODIRTY(inode, quota_bytes);
2075         return retval;
2076 }