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TOMOYO Linux Cross Reference
Linux/fs/reiserfs/lbalance.c

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  1 /*
  2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
  3  */
  4 
  5 #include <linux/uaccess.h>
  6 #include <linux/string.h>
  7 #include <linux/time.h>
  8 #include "reiserfs.h"
  9 #include <linux/buffer_head.h>
 10 
 11 /*
 12  * copy copy_count entries from source directory item to dest buffer
 13  * (creating new item if needed)
 14  */
 15 static void leaf_copy_dir_entries(struct buffer_info *dest_bi,
 16                                   struct buffer_head *source, int last_first,
 17                                   int item_num, int from, int copy_count)
 18 {
 19         struct buffer_head *dest = dest_bi->bi_bh;
 20         /*
 21          * either the number of target item, or if we must create a
 22          * new item, the number of the item we will create it next to
 23          */
 24         int item_num_in_dest;
 25 
 26         struct item_head *ih;
 27         struct reiserfs_de_head *deh;
 28         int copy_records_len;   /* length of all records in item to be copied */
 29         char *records;
 30 
 31         ih = item_head(source, item_num);
 32 
 33         RFALSE(!is_direntry_le_ih(ih), "vs-10000: item must be directory item");
 34 
 35         /*
 36          * length of all record to be copied and first byte of
 37          * the last of them
 38          */
 39         deh = B_I_DEH(source, ih);
 40         if (copy_count) {
 41                 copy_records_len = (from ? deh_location(&deh[from - 1]) :
 42                                     ih_item_len(ih)) -
 43                     deh_location(&deh[from + copy_count - 1]);
 44                 records =
 45                     source->b_data + ih_location(ih) +
 46                     deh_location(&deh[from + copy_count - 1]);
 47         } else {
 48                 copy_records_len = 0;
 49                 records = NULL;
 50         }
 51 
 52         /* when copy last to first, dest buffer can contain 0 items */
 53         item_num_in_dest =
 54             (last_first ==
 55              LAST_TO_FIRST) ? ((B_NR_ITEMS(dest)) ? 0 : -1) : (B_NR_ITEMS(dest)
 56                                                                - 1);
 57 
 58         /*
 59          * if there are no items in dest or the first/last item in
 60          * dest is not item of the same directory
 61          */
 62         if ((item_num_in_dest == -1) ||
 63             (last_first == FIRST_TO_LAST && le_ih_k_offset(ih) == DOT_OFFSET) ||
 64             (last_first == LAST_TO_FIRST
 65              && comp_short_le_keys /*COMP_SHORT_KEYS */ (&ih->ih_key,
 66                                                          leaf_key(dest,
 67                                                                   item_num_in_dest))))
 68         {
 69                 /* create new item in dest */
 70                 struct item_head new_ih;
 71 
 72                 /* form item header */
 73                 memcpy(&new_ih.ih_key, &ih->ih_key, KEY_SIZE);
 74                 put_ih_version(&new_ih, KEY_FORMAT_3_5);
 75                 /* calculate item len */
 76                 put_ih_item_len(&new_ih,
 77                                 DEH_SIZE * copy_count + copy_records_len);
 78                 put_ih_entry_count(&new_ih, 0);
 79 
 80                 if (last_first == LAST_TO_FIRST) {
 81                         /* form key by the following way */
 82                         if (from < ih_entry_count(ih)) {
 83                                 set_le_ih_k_offset(&new_ih,
 84                                                    deh_offset(&deh[from]));
 85                         } else {
 86                                 /*
 87                                  * no entries will be copied to this
 88                                  * item in this function
 89                                  */
 90                                 set_le_ih_k_offset(&new_ih, U32_MAX);
 91                                 /*
 92                                  * this item is not yet valid, but we
 93                                  * want I_IS_DIRECTORY_ITEM to return 1
 94                                  * for it, so we -1
 95                                  */
 96                         }
 97                         set_le_key_k_type(KEY_FORMAT_3_5, &new_ih.ih_key,
 98                                           TYPE_DIRENTRY);
 99                 }
100 
101                 /* insert item into dest buffer */
102                 leaf_insert_into_buf(dest_bi,
103                                      (last_first ==
104                                       LAST_TO_FIRST) ? 0 : B_NR_ITEMS(dest),
105                                      &new_ih, NULL, 0);
106         } else {
107                 /* prepare space for entries */
108                 leaf_paste_in_buffer(dest_bi,
109                                      (last_first ==
110                                       FIRST_TO_LAST) ? (B_NR_ITEMS(dest) -
111                                                         1) : 0, MAX_US_INT,
112                                      DEH_SIZE * copy_count + copy_records_len,
113                                      records, 0);
114         }
115 
116         item_num_in_dest =
117             (last_first == FIRST_TO_LAST) ? (B_NR_ITEMS(dest) - 1) : 0;
118 
119         leaf_paste_entries(dest_bi, item_num_in_dest,
120                            (last_first ==
121                             FIRST_TO_LAST) ? ih_entry_count(item_head(dest,
122                                                                           item_num_in_dest))
123                            : 0, copy_count, deh + from, records,
124                            DEH_SIZE * copy_count + copy_records_len);
125 }
126 
127 /*
128  * Copy the first (if last_first == FIRST_TO_LAST) or last
129  * (last_first == LAST_TO_FIRST) item or part of it or nothing
130  * (see the return 0 below) from SOURCE to the end (if last_first)
131  * or beginning (!last_first) of the DEST
132  */
133 /* returns 1 if anything was copied, else 0 */
134 static int leaf_copy_boundary_item(struct buffer_info *dest_bi,
135                                    struct buffer_head *src, int last_first,
136                                    int bytes_or_entries)
137 {
138         struct buffer_head *dest = dest_bi->bi_bh;
139         /* number of items in the source and destination buffers */
140         int dest_nr_item, src_nr_item;
141         struct item_head *ih;
142         struct item_head *dih;
143 
144         dest_nr_item = B_NR_ITEMS(dest);
145 
146         /*
147          * if ( DEST is empty or first item of SOURCE and last item of
148          * DEST are the items of different objects or of different types )
149          * then there is no need to treat this item differently from the
150          * other items that we copy, so we return
151          */
152         if (last_first == FIRST_TO_LAST) {
153                 ih = item_head(src, 0);
154                 dih = item_head(dest, dest_nr_item - 1);
155 
156                 /* there is nothing to merge */
157                 if (!dest_nr_item
158                     || (!op_is_left_mergeable(&ih->ih_key, src->b_size)))
159                         return 0;
160 
161                 RFALSE(!ih_item_len(ih),
162                        "vs-10010: item can not have empty length");
163 
164                 if (is_direntry_le_ih(ih)) {
165                         if (bytes_or_entries == -1)
166                                 /* copy all entries to dest */
167                                 bytes_or_entries = ih_entry_count(ih);
168                         leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST, 0, 0,
169                                               bytes_or_entries);
170                         return 1;
171                 }
172 
173                 /*
174                  * copy part of the body of the first item of SOURCE
175                  * to the end of the body of the last item of the DEST
176                  * part defined by 'bytes_or_entries'; if bytes_or_entries
177                  * == -1 copy whole body; don't create new item header
178                  */
179                 if (bytes_or_entries == -1)
180                         bytes_or_entries = ih_item_len(ih);
181 
182 #ifdef CONFIG_REISERFS_CHECK
183                 else {
184                         if (bytes_or_entries == ih_item_len(ih)
185                             && is_indirect_le_ih(ih))
186                                 if (get_ih_free_space(ih))
187                                         reiserfs_panic(sb_from_bi(dest_bi),
188                                                        "vs-10020",
189                                                        "last unformatted node "
190                                                        "must be filled "
191                                                        "entirely (%h)", ih);
192                 }
193 #endif
194 
195                 /*
196                  * merge first item (or its part) of src buffer with the last
197                  * item of dest buffer. Both are of the same file
198                  */
199                 leaf_paste_in_buffer(dest_bi,
200                                      dest_nr_item - 1, ih_item_len(dih),
201                                      bytes_or_entries, ih_item_body(src, ih), 0);
202 
203                 if (is_indirect_le_ih(dih)) {
204                         RFALSE(get_ih_free_space(dih),
205                                "vs-10030: merge to left: last unformatted node of non-last indirect item %h must have zerto free space",
206                                ih);
207                         if (bytes_or_entries == ih_item_len(ih))
208                                 set_ih_free_space(dih, get_ih_free_space(ih));
209                 }
210 
211                 return 1;
212         }
213 
214         /* copy boundary item to right (last_first == LAST_TO_FIRST) */
215 
216         /*
217          * (DEST is empty or last item of SOURCE and first item of DEST
218          * are the items of different object or of different types)
219          */
220         src_nr_item = B_NR_ITEMS(src);
221         ih = item_head(src, src_nr_item - 1);
222         dih = item_head(dest, 0);
223 
224         if (!dest_nr_item || !op_is_left_mergeable(&dih->ih_key, src->b_size))
225                 return 0;
226 
227         if (is_direntry_le_ih(ih)) {
228                 /*
229                  * bytes_or_entries = entries number in last
230                  * item body of SOURCE
231                  */
232                 if (bytes_or_entries == -1)
233                         bytes_or_entries = ih_entry_count(ih);
234 
235                 leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
236                                       src_nr_item - 1,
237                                       ih_entry_count(ih) - bytes_or_entries,
238                                       bytes_or_entries);
239                 return 1;
240         }
241 
242         /*
243          * copy part of the body of the last item of SOURCE to the
244          * begin of the body of the first item of the DEST; part defined
245          * by 'bytes_or_entries'; if byte_or_entriess == -1 copy whole body;
246          * change first item key of the DEST; don't create new item header
247          */
248 
249         RFALSE(is_indirect_le_ih(ih) && get_ih_free_space(ih),
250                "vs-10040: merge to right: last unformatted node of non-last indirect item must be filled entirely (%h)",
251                ih);
252 
253         if (bytes_or_entries == -1) {
254                 /* bytes_or_entries = length of last item body of SOURCE */
255                 bytes_or_entries = ih_item_len(ih);
256 
257                 RFALSE(le_ih_k_offset(dih) !=
258                        le_ih_k_offset(ih) + op_bytes_number(ih, src->b_size),
259                        "vs-10050: items %h and %h do not match", ih, dih);
260 
261                 /* change first item key of the DEST */
262                 set_le_ih_k_offset(dih, le_ih_k_offset(ih));
263 
264                 /* item becomes non-mergeable */
265                 /* or mergeable if left item was */
266                 set_le_ih_k_type(dih, le_ih_k_type(ih));
267         } else {
268                 /* merge to right only part of item */
269                 RFALSE(ih_item_len(ih) <= bytes_or_entries,
270                        "vs-10060: no so much bytes %lu (needed %lu)",
271                        (unsigned long)ih_item_len(ih),
272                        (unsigned long)bytes_or_entries);
273 
274                 /* change first item key of the DEST */
275                 if (is_direct_le_ih(dih)) {
276                         RFALSE(le_ih_k_offset(dih) <=
277                                (unsigned long)bytes_or_entries,
278                                "vs-10070: dih %h, bytes_or_entries(%d)", dih,
279                                bytes_or_entries);
280                         set_le_ih_k_offset(dih,
281                                            le_ih_k_offset(dih) -
282                                            bytes_or_entries);
283                 } else {
284                         RFALSE(le_ih_k_offset(dih) <=
285                                (bytes_or_entries / UNFM_P_SIZE) * dest->b_size,
286                                "vs-10080: dih %h, bytes_or_entries(%d)",
287                                dih,
288                                (bytes_or_entries / UNFM_P_SIZE) * dest->b_size);
289                         set_le_ih_k_offset(dih,
290                                            le_ih_k_offset(dih) -
291                                            ((bytes_or_entries / UNFM_P_SIZE) *
292                                             dest->b_size));
293                 }
294         }
295 
296         leaf_paste_in_buffer(dest_bi, 0, 0, bytes_or_entries,
297                              ih_item_body(src,
298                                        ih) + ih_item_len(ih) - bytes_or_entries,
299                              0);
300         return 1;
301 }
302 
303 /*
304  * copy cpy_mun items from buffer src to buffer dest
305  * last_first == FIRST_TO_LAST means, that we copy cpy_num items beginning
306  *                             from first-th item in src to tail of dest
307  * last_first == LAST_TO_FIRST means, that we copy cpy_num items beginning
308  *                             from first-th item in src to head of dest
309  */
310 static void leaf_copy_items_entirely(struct buffer_info *dest_bi,
311                                      struct buffer_head *src, int last_first,
312                                      int first, int cpy_num)
313 {
314         struct buffer_head *dest;
315         int nr, free_space;
316         int dest_before;
317         int last_loc, last_inserted_loc, location;
318         int i, j;
319         struct block_head *blkh;
320         struct item_head *ih;
321 
322         RFALSE(last_first != LAST_TO_FIRST && last_first != FIRST_TO_LAST,
323                "vs-10090: bad last_first parameter %d", last_first);
324         RFALSE(B_NR_ITEMS(src) - first < cpy_num,
325                "vs-10100: too few items in source %d, required %d from %d",
326                B_NR_ITEMS(src), cpy_num, first);
327         RFALSE(cpy_num < 0, "vs-10110: can not copy negative amount of items");
328         RFALSE(!dest_bi, "vs-10120: can not copy negative amount of items");
329 
330         dest = dest_bi->bi_bh;
331 
332         RFALSE(!dest, "vs-10130: can not copy negative amount of items");
333 
334         if (cpy_num == 0)
335                 return;
336 
337         blkh = B_BLK_HEAD(dest);
338         nr = blkh_nr_item(blkh);
339         free_space = blkh_free_space(blkh);
340 
341         /*
342          * we will insert items before 0-th or nr-th item in dest buffer.
343          * It depends of last_first parameter
344          */
345         dest_before = (last_first == LAST_TO_FIRST) ? 0 : nr;
346 
347         /* location of head of first new item */
348         ih = item_head(dest, dest_before);
349 
350         RFALSE(blkh_free_space(blkh) < cpy_num * IH_SIZE,
351                "vs-10140: not enough free space for headers %d (needed %d)",
352                B_FREE_SPACE(dest), cpy_num * IH_SIZE);
353 
354         /* prepare space for headers */
355         memmove(ih + cpy_num, ih, (nr - dest_before) * IH_SIZE);
356 
357         /* copy item headers */
358         memcpy(ih, item_head(src, first), cpy_num * IH_SIZE);
359 
360         free_space -= (IH_SIZE * cpy_num);
361         set_blkh_free_space(blkh, free_space);
362 
363         /* location of unmovable item */
364         j = location = (dest_before == 0) ? dest->b_size : ih_location(ih - 1);
365         for (i = dest_before; i < nr + cpy_num; i++) {
366                 location -= ih_item_len(ih + i - dest_before);
367                 put_ih_location(ih + i - dest_before, location);
368         }
369 
370         /* prepare space for items */
371         last_loc = ih_location(&ih[nr + cpy_num - 1 - dest_before]);
372         last_inserted_loc = ih_location(&ih[cpy_num - 1]);
373 
374         /* check free space */
375         RFALSE(free_space < j - last_inserted_loc,
376                "vs-10150: not enough free space for items %d (needed %d)",
377                free_space, j - last_inserted_loc);
378 
379         memmove(dest->b_data + last_loc,
380                 dest->b_data + last_loc + j - last_inserted_loc,
381                 last_inserted_loc - last_loc);
382 
383         /* copy items */
384         memcpy(dest->b_data + last_inserted_loc,
385                item_body(src, (first + cpy_num - 1)),
386                j - last_inserted_loc);
387 
388         /* sizes, item number */
389         set_blkh_nr_item(blkh, nr + cpy_num);
390         set_blkh_free_space(blkh, free_space - (j - last_inserted_loc));
391 
392         do_balance_mark_leaf_dirty(dest_bi->tb, dest, 0);
393 
394         if (dest_bi->bi_parent) {
395                 struct disk_child *t_dc;
396                 t_dc = B_N_CHILD(dest_bi->bi_parent, dest_bi->bi_position);
397                 RFALSE(dc_block_number(t_dc) != dest->b_blocknr,
398                        "vs-10160: block number in bh does not match to field in disk_child structure %lu and %lu",
399                        (long unsigned)dest->b_blocknr,
400                        (long unsigned)dc_block_number(t_dc));
401                 put_dc_size(t_dc,
402                             dc_size(t_dc) + (j - last_inserted_loc +
403                                              IH_SIZE * cpy_num));
404 
405                 do_balance_mark_internal_dirty(dest_bi->tb, dest_bi->bi_parent,
406                                                0);
407         }
408 }
409 
410 /*
411  * This function splits the (liquid) item into two items (useful when
412  * shifting part of an item into another node.)
413  */
414 static void leaf_item_bottle(struct buffer_info *dest_bi,
415                              struct buffer_head *src, int last_first,
416                              int item_num, int cpy_bytes)
417 {
418         struct buffer_head *dest = dest_bi->bi_bh;
419         struct item_head *ih;
420 
421         RFALSE(cpy_bytes == -1,
422                "vs-10170: bytes == - 1 means: do not split item");
423 
424         if (last_first == FIRST_TO_LAST) {
425                 /*
426                  * if ( if item in position item_num in buffer SOURCE
427                  * is directory item )
428                  */
429                 ih = item_head(src, item_num);
430                 if (is_direntry_le_ih(ih))
431                         leaf_copy_dir_entries(dest_bi, src, FIRST_TO_LAST,
432                                               item_num, 0, cpy_bytes);
433                 else {
434                         struct item_head n_ih;
435 
436                         /*
437                          * copy part of the body of the item number 'item_num'
438                          * of SOURCE to the end of the DEST part defined by
439                          * 'cpy_bytes'; create new item header; change old
440                          * item_header (????); n_ih = new item_header;
441                          */
442                         memcpy(&n_ih, ih, IH_SIZE);
443                         put_ih_item_len(&n_ih, cpy_bytes);
444                         if (is_indirect_le_ih(ih)) {
445                                 RFALSE(cpy_bytes == ih_item_len(ih)
446                                        && get_ih_free_space(ih),
447                                        "vs-10180: when whole indirect item is bottle to left neighbor, it must have free_space==0 (not %lu)",
448                                        (long unsigned)get_ih_free_space(ih));
449                                 set_ih_free_space(&n_ih, 0);
450                         }
451 
452                         RFALSE(op_is_left_mergeable(&ih->ih_key, src->b_size),
453                                "vs-10190: bad mergeability of item %h", ih);
454                         n_ih.ih_version = ih->ih_version;       /* JDM Endian safe, both le */
455                         leaf_insert_into_buf(dest_bi, B_NR_ITEMS(dest), &n_ih,
456                                              item_body(src, item_num), 0);
457                 }
458         } else {
459                 /*
460                  * if ( if item in position item_num in buffer
461                  * SOURCE is directory item )
462                  */
463                 ih = item_head(src, item_num);
464                 if (is_direntry_le_ih(ih))
465                         leaf_copy_dir_entries(dest_bi, src, LAST_TO_FIRST,
466                                               item_num,
467                                               ih_entry_count(ih) - cpy_bytes,
468                                               cpy_bytes);
469                 else {
470                         struct item_head n_ih;
471 
472                         /*
473                          * copy part of the body of the item number 'item_num'
474                          * of SOURCE to the begin of the DEST part defined by
475                          * 'cpy_bytes'; create new item header;
476                          * n_ih = new item_header;
477                          */
478                         memcpy(&n_ih.ih_key, &ih->ih_key, KEY_SIZE);
479 
480                         /* Endian safe, both le */
481                         n_ih.ih_version = ih->ih_version;
482 
483                         if (is_direct_le_ih(ih)) {
484                                 set_le_ih_k_offset(&n_ih,
485                                                    le_ih_k_offset(ih) +
486                                                    ih_item_len(ih) - cpy_bytes);
487                                 set_le_ih_k_type(&n_ih, TYPE_DIRECT);
488                                 set_ih_free_space(&n_ih, MAX_US_INT);
489                         } else {
490                                 /* indirect item */
491                                 RFALSE(!cpy_bytes && get_ih_free_space(ih),
492                                        "vs-10200: ih->ih_free_space must be 0 when indirect item will be appended");
493                                 set_le_ih_k_offset(&n_ih,
494                                                    le_ih_k_offset(ih) +
495                                                    (ih_item_len(ih) -
496                                                     cpy_bytes) / UNFM_P_SIZE *
497                                                    dest->b_size);
498                                 set_le_ih_k_type(&n_ih, TYPE_INDIRECT);
499                                 set_ih_free_space(&n_ih, get_ih_free_space(ih));
500                         }
501 
502                         /* set item length */
503                         put_ih_item_len(&n_ih, cpy_bytes);
504 
505                         /* Endian safe, both le */
506                         n_ih.ih_version = ih->ih_version;
507 
508                         leaf_insert_into_buf(dest_bi, 0, &n_ih,
509                                              item_body(src, item_num) +
510                                                 ih_item_len(ih) - cpy_bytes, 0);
511                 }
512         }
513 }
514 
515 /*
516  * If cpy_bytes equals minus one than copy cpy_num whole items from SOURCE
517  * to DEST.  If cpy_bytes not equal to minus one than copy cpy_num-1 whole
518  * items from SOURCE to DEST.  From last item copy cpy_num bytes for regular
519  * item and cpy_num directory entries for directory item.
520  */
521 static int leaf_copy_items(struct buffer_info *dest_bi, struct buffer_head *src,
522                            int last_first, int cpy_num, int cpy_bytes)
523 {
524         struct buffer_head *dest;
525         int pos, i, src_nr_item, bytes;
526 
527         dest = dest_bi->bi_bh;
528         RFALSE(!dest || !src, "vs-10210: !dest || !src");
529         RFALSE(last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST,
530                "vs-10220:last_first != FIRST_TO_LAST && last_first != LAST_TO_FIRST");
531         RFALSE(B_NR_ITEMS(src) < cpy_num,
532                "vs-10230: No enough items: %d, req. %d", B_NR_ITEMS(src),
533                cpy_num);
534         RFALSE(cpy_num < 0, "vs-10240: cpy_num < 0 (%d)", cpy_num);
535 
536         if (cpy_num == 0)
537                 return 0;
538 
539         if (last_first == FIRST_TO_LAST) {
540                 /* copy items to left */
541                 pos = 0;
542                 if (cpy_num == 1)
543                         bytes = cpy_bytes;
544                 else
545                         bytes = -1;
546 
547                 /*
548                  * copy the first item or it part or nothing to the end of
549                  * the DEST (i = leaf_copy_boundary_item(DEST,SOURCE,0,bytes))
550                  */
551                 i = leaf_copy_boundary_item(dest_bi, src, FIRST_TO_LAST, bytes);
552                 cpy_num -= i;
553                 if (cpy_num == 0)
554                         return i;
555                 pos += i;
556                 if (cpy_bytes == -1)
557                         /*
558                          * copy first cpy_num items starting from position
559                          * 'pos' of SOURCE to end of DEST
560                          */
561                         leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
562                                                  pos, cpy_num);
563                 else {
564                         /*
565                          * copy first cpy_num-1 items starting from position
566                          * 'pos-1' of the SOURCE to the end of the DEST
567                          */
568                         leaf_copy_items_entirely(dest_bi, src, FIRST_TO_LAST,
569                                                  pos, cpy_num - 1);
570 
571                         /*
572                          * copy part of the item which number is
573                          * cpy_num+pos-1 to the end of the DEST
574                          */
575                         leaf_item_bottle(dest_bi, src, FIRST_TO_LAST,
576                                          cpy_num + pos - 1, cpy_bytes);
577                 }
578         } else {
579                 /* copy items to right */
580                 src_nr_item = B_NR_ITEMS(src);
581                 if (cpy_num == 1)
582                         bytes = cpy_bytes;
583                 else
584                         bytes = -1;
585 
586                 /*
587                  * copy the last item or it part or nothing to the
588                  * begin of the DEST
589                  * (i = leaf_copy_boundary_item(DEST,SOURCE,1,bytes));
590                  */
591                 i = leaf_copy_boundary_item(dest_bi, src, LAST_TO_FIRST, bytes);
592 
593                 cpy_num -= i;
594                 if (cpy_num == 0)
595                         return i;
596 
597                 pos = src_nr_item - cpy_num - i;
598                 if (cpy_bytes == -1) {
599                         /*
600                          * starting from position 'pos' copy last cpy_num
601                          * items of SOURCE to begin of DEST
602                          */
603                         leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
604                                                  pos, cpy_num);
605                 } else {
606                         /*
607                          * copy last cpy_num-1 items starting from position
608                          * 'pos+1' of the SOURCE to the begin of the DEST;
609                          */
610                         leaf_copy_items_entirely(dest_bi, src, LAST_TO_FIRST,
611                                                  pos + 1, cpy_num - 1);
612 
613                         /*
614                          * copy part of the item which number is pos to
615                          * the begin of the DEST
616                          */
617                         leaf_item_bottle(dest_bi, src, LAST_TO_FIRST, pos,
618                                          cpy_bytes);
619                 }
620         }
621         return i;
622 }
623 
624 /*
625  * there are types of coping: from S[0] to L[0], from S[0] to R[0],
626  * from R[0] to L[0]. for each of these we have to define parent and
627  * positions of destination and source buffers
628  */
629 static void leaf_define_dest_src_infos(int shift_mode, struct tree_balance *tb,
630                                        struct buffer_info *dest_bi,
631                                        struct buffer_info *src_bi,
632                                        int *first_last,
633                                        struct buffer_head *Snew)
634 {
635         memset(dest_bi, 0, sizeof(struct buffer_info));
636         memset(src_bi, 0, sizeof(struct buffer_info));
637 
638         /* define dest, src, dest parent, dest position */
639         switch (shift_mode) {
640         case LEAF_FROM_S_TO_L:  /* it is used in leaf_shift_left */
641                 src_bi->tb = tb;
642                 src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
643                 src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
644 
645                 /* src->b_item_order */
646                 src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
647                 dest_bi->tb = tb;
648                 dest_bi->bi_bh = tb->L[0];
649                 dest_bi->bi_parent = tb->FL[0];
650                 dest_bi->bi_position = get_left_neighbor_position(tb, 0);
651                 *first_last = FIRST_TO_LAST;
652                 break;
653 
654         case LEAF_FROM_S_TO_R:  /* it is used in leaf_shift_right */
655                 src_bi->tb = tb;
656                 src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
657                 src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
658                 src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
659                 dest_bi->tb = tb;
660                 dest_bi->bi_bh = tb->R[0];
661                 dest_bi->bi_parent = tb->FR[0];
662                 dest_bi->bi_position = get_right_neighbor_position(tb, 0);
663                 *first_last = LAST_TO_FIRST;
664                 break;
665 
666         case LEAF_FROM_R_TO_L:  /* it is used in balance_leaf_when_delete */
667                 src_bi->tb = tb;
668                 src_bi->bi_bh = tb->R[0];
669                 src_bi->bi_parent = tb->FR[0];
670                 src_bi->bi_position = get_right_neighbor_position(tb, 0);
671                 dest_bi->tb = tb;
672                 dest_bi->bi_bh = tb->L[0];
673                 dest_bi->bi_parent = tb->FL[0];
674                 dest_bi->bi_position = get_left_neighbor_position(tb, 0);
675                 *first_last = FIRST_TO_LAST;
676                 break;
677 
678         case LEAF_FROM_L_TO_R:  /* it is used in balance_leaf_when_delete */
679                 src_bi->tb = tb;
680                 src_bi->bi_bh = tb->L[0];
681                 src_bi->bi_parent = tb->FL[0];
682                 src_bi->bi_position = get_left_neighbor_position(tb, 0);
683                 dest_bi->tb = tb;
684                 dest_bi->bi_bh = tb->R[0];
685                 dest_bi->bi_parent = tb->FR[0];
686                 dest_bi->bi_position = get_right_neighbor_position(tb, 0);
687                 *first_last = LAST_TO_FIRST;
688                 break;
689 
690         case LEAF_FROM_S_TO_SNEW:
691                 src_bi->tb = tb;
692                 src_bi->bi_bh = PATH_PLAST_BUFFER(tb->tb_path);
693                 src_bi->bi_parent = PATH_H_PPARENT(tb->tb_path, 0);
694                 src_bi->bi_position = PATH_H_B_ITEM_ORDER(tb->tb_path, 0);
695                 dest_bi->tb = tb;
696                 dest_bi->bi_bh = Snew;
697                 dest_bi->bi_parent = NULL;
698                 dest_bi->bi_position = 0;
699                 *first_last = LAST_TO_FIRST;
700                 break;
701 
702         default:
703                 reiserfs_panic(sb_from_bi(src_bi), "vs-10250",
704                                "shift type is unknown (%d)", shift_mode);
705         }
706         RFALSE(!src_bi->bi_bh || !dest_bi->bi_bh,
707                "vs-10260: mode==%d, source (%p) or dest (%p) buffer is initialized incorrectly",
708                shift_mode, src_bi->bi_bh, dest_bi->bi_bh);
709 }
710 
711 /*
712  * copy mov_num items and mov_bytes of the (mov_num-1)th item to
713  * neighbor. Delete them from source
714  */
715 int leaf_move_items(int shift_mode, struct tree_balance *tb, int mov_num,
716                     int mov_bytes, struct buffer_head *Snew)
717 {
718         int ret_value;
719         struct buffer_info dest_bi, src_bi;
720         int first_last;
721 
722         leaf_define_dest_src_infos(shift_mode, tb, &dest_bi, &src_bi,
723                                    &first_last, Snew);
724 
725         ret_value =
726             leaf_copy_items(&dest_bi, src_bi.bi_bh, first_last, mov_num,
727                             mov_bytes);
728 
729         leaf_delete_items(&src_bi, first_last,
730                           (first_last ==
731                            FIRST_TO_LAST) ? 0 : (B_NR_ITEMS(src_bi.bi_bh) -
732                                                  mov_num), mov_num, mov_bytes);
733 
734         return ret_value;
735 }
736 
737 /*
738  * Shift shift_num items (and shift_bytes of last shifted item if
739  * shift_bytes != -1) from S[0] to L[0] and replace the delimiting key
740  */
741 int leaf_shift_left(struct tree_balance *tb, int shift_num, int shift_bytes)
742 {
743         struct buffer_head *S0 = PATH_PLAST_BUFFER(tb->tb_path);
744         int i;
745 
746         /*
747          * move shift_num (and shift_bytes bytes) items from S[0]
748          * to left neighbor L[0]
749          */
750         i = leaf_move_items(LEAF_FROM_S_TO_L, tb, shift_num, shift_bytes, NULL);
751 
752         if (shift_num) {
753                 /* number of items in S[0] == 0 */
754                 if (B_NR_ITEMS(S0) == 0) {
755 
756                         RFALSE(shift_bytes != -1,
757                                "vs-10270: S0 is empty now, but shift_bytes != -1 (%d)",
758                                shift_bytes);
759 #ifdef CONFIG_REISERFS_CHECK
760                         if (tb->tb_mode == M_PASTE || tb->tb_mode == M_INSERT) {
761                                 print_cur_tb("vs-10275");
762                                 reiserfs_panic(tb->tb_sb, "vs-10275",
763                                                "balance condition corrupted "
764                                                "(%c)", tb->tb_mode);
765                         }
766 #endif
767 
768                         if (PATH_H_POSITION(tb->tb_path, 1) == 0)
769                                 replace_key(tb, tb->CFL[0], tb->lkey[0],
770                                             PATH_H_PPARENT(tb->tb_path, 0), 0);
771 
772                 } else {
773                         /* replace lkey in CFL[0] by 0-th key from S[0]; */
774                         replace_key(tb, tb->CFL[0], tb->lkey[0], S0, 0);
775 
776                         RFALSE((shift_bytes != -1 &&
777                                 !(is_direntry_le_ih(item_head(S0, 0))
778                                   && !ih_entry_count(item_head(S0, 0)))) &&
779                                (!op_is_left_mergeable
780                                 (leaf_key(S0, 0), S0->b_size)),
781                                "vs-10280: item must be mergeable");
782                 }
783         }
784 
785         return i;
786 }
787 
788 /* CLEANING STOPPED HERE */
789 
790 /*
791  * Shift shift_num (shift_bytes) items from S[0] to the right neighbor,
792  * and replace the delimiting key
793  */
794 int leaf_shift_right(struct tree_balance *tb, int shift_num, int shift_bytes)
795 {
796         int ret_value;
797 
798         /*
799          * move shift_num (and shift_bytes) items from S[0] to
800          * right neighbor R[0]
801          */
802         ret_value =
803             leaf_move_items(LEAF_FROM_S_TO_R, tb, shift_num, shift_bytes, NULL);
804 
805         /* replace rkey in CFR[0] by the 0-th key from R[0] */
806         if (shift_num) {
807                 replace_key(tb, tb->CFR[0], tb->rkey[0], tb->R[0], 0);
808 
809         }
810 
811         return ret_value;
812 }
813 
814 static void leaf_delete_items_entirely(struct buffer_info *bi,
815                                        int first, int del_num);
816 /*
817  * If del_bytes == -1, starting from position 'first' delete del_num
818  * items in whole in buffer CUR.
819  *   If not.
820  *   If last_first == 0. Starting from position 'first' delete del_num-1
821  *   items in whole. Delete part of body of the first item. Part defined by
822  *   del_bytes. Don't delete first item header
823  *   If last_first == 1. Starting from position 'first+1' delete del_num-1
824  *   items in whole. Delete part of body of the last item . Part defined by
825  *   del_bytes. Don't delete last item header.
826 */
827 void leaf_delete_items(struct buffer_info *cur_bi, int last_first,
828                        int first, int del_num, int del_bytes)
829 {
830         struct buffer_head *bh;
831         int item_amount = B_NR_ITEMS(bh = cur_bi->bi_bh);
832 
833         RFALSE(!bh, "10155: bh is not defined");
834         RFALSE(del_num < 0, "10160: del_num can not be < 0. del_num==%d",
835                del_num);
836         RFALSE(first < 0
837                || first + del_num > item_amount,
838                "10165: invalid number of first item to be deleted (%d) or "
839                "no so much items (%d) to delete (only %d)", first,
840                first + del_num, item_amount);
841 
842         if (del_num == 0)
843                 return;
844 
845         if (first == 0 && del_num == item_amount && del_bytes == -1) {
846                 make_empty_node(cur_bi);
847                 do_balance_mark_leaf_dirty(cur_bi->tb, bh, 0);
848                 return;
849         }
850 
851         if (del_bytes == -1)
852                 /* delete del_num items beginning from item in position first */
853                 leaf_delete_items_entirely(cur_bi, first, del_num);
854         else {
855                 if (last_first == FIRST_TO_LAST) {
856                         /*
857                          * delete del_num-1 items beginning from
858                          * item in position first
859                          */
860                         leaf_delete_items_entirely(cur_bi, first, del_num - 1);
861 
862                         /*
863                          * delete the part of the first item of the bh
864                          * do not delete item header
865                          */
866                         leaf_cut_from_buffer(cur_bi, 0, 0, del_bytes);
867                 } else {
868                         struct item_head *ih;
869                         int len;
870 
871                         /*
872                          * delete del_num-1 items beginning from
873                          * item in position first+1
874                          */
875                         leaf_delete_items_entirely(cur_bi, first + 1,
876                                                    del_num - 1);
877 
878                         ih = item_head(bh, B_NR_ITEMS(bh) - 1);
879                         if (is_direntry_le_ih(ih))
880                                 /* the last item is directory  */
881                                 /*
882                                  * len = numbers of directory entries
883                                  * in this item
884                                  */
885                                 len = ih_entry_count(ih);
886                         else
887                                 /* len = body len of item */
888                                 len = ih_item_len(ih);
889 
890                         /*
891                          * delete the part of the last item of the bh
892                          * do not delete item header
893                          */
894                         leaf_cut_from_buffer(cur_bi, B_NR_ITEMS(bh) - 1,
895                                              len - del_bytes, del_bytes);
896                 }
897         }
898 }
899 
900 /* insert item into the leaf node in position before */
901 void leaf_insert_into_buf(struct buffer_info *bi, int before,
902                           struct item_head * const inserted_item_ih,
903                           const char * const inserted_item_body,
904                           int zeros_number)
905 {
906         struct buffer_head *bh = bi->bi_bh;
907         int nr, free_space;
908         struct block_head *blkh;
909         struct item_head *ih;
910         int i;
911         int last_loc, unmoved_loc;
912         char *to;
913 
914         blkh = B_BLK_HEAD(bh);
915         nr = blkh_nr_item(blkh);
916         free_space = blkh_free_space(blkh);
917 
918         /* check free space */
919         RFALSE(free_space < ih_item_len(inserted_item_ih) + IH_SIZE,
920                "vs-10170: not enough free space in block %z, new item %h",
921                bh, inserted_item_ih);
922         RFALSE(zeros_number > ih_item_len(inserted_item_ih),
923                "vs-10172: zero number == %d, item length == %d",
924                zeros_number, ih_item_len(inserted_item_ih));
925 
926         /* get item new item must be inserted before */
927         ih = item_head(bh, before);
928 
929         /* prepare space for the body of new item */
930         last_loc = nr ? ih_location(&ih[nr - before - 1]) : bh->b_size;
931         unmoved_loc = before ? ih_location(ih - 1) : bh->b_size;
932 
933         memmove(bh->b_data + last_loc - ih_item_len(inserted_item_ih),
934                 bh->b_data + last_loc, unmoved_loc - last_loc);
935 
936         to = bh->b_data + unmoved_loc - ih_item_len(inserted_item_ih);
937         memset(to, 0, zeros_number);
938         to += zeros_number;
939 
940         /* copy body to prepared space */
941         if (inserted_item_body)
942                 memmove(to, inserted_item_body,
943                         ih_item_len(inserted_item_ih) - zeros_number);
944         else
945                 memset(to, '\0', ih_item_len(inserted_item_ih) - zeros_number);
946 
947         /* insert item header */
948         memmove(ih + 1, ih, IH_SIZE * (nr - before));
949         memmove(ih, inserted_item_ih, IH_SIZE);
950 
951         /* change locations */
952         for (i = before; i < nr + 1; i++) {
953                 unmoved_loc -= ih_item_len(&ih[i - before]);
954                 put_ih_location(&ih[i - before], unmoved_loc);
955         }
956 
957         /* sizes, free space, item number */
958         set_blkh_nr_item(blkh, blkh_nr_item(blkh) + 1);
959         set_blkh_free_space(blkh,
960                             free_space - (IH_SIZE +
961                                           ih_item_len(inserted_item_ih)));
962         do_balance_mark_leaf_dirty(bi->tb, bh, 1);
963 
964         if (bi->bi_parent) {
965                 struct disk_child *t_dc;
966                 t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
967                 put_dc_size(t_dc,
968                             dc_size(t_dc) + (IH_SIZE +
969                                              ih_item_len(inserted_item_ih)));
970                 do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
971         }
972 }
973 
974 /*
975  * paste paste_size bytes to affected_item_num-th item.
976  * When item is a directory, this only prepare space for new entries
977  */
978 void leaf_paste_in_buffer(struct buffer_info *bi, int affected_item_num,
979                           int pos_in_item, int paste_size,
980                           const char *body, int zeros_number)
981 {
982         struct buffer_head *bh = bi->bi_bh;
983         int nr, free_space;
984         struct block_head *blkh;
985         struct item_head *ih;
986         int i;
987         int last_loc, unmoved_loc;
988 
989         blkh = B_BLK_HEAD(bh);
990         nr = blkh_nr_item(blkh);
991         free_space = blkh_free_space(blkh);
992 
993         /* check free space */
994         RFALSE(free_space < paste_size,
995                "vs-10175: not enough free space: needed %d, available %d",
996                paste_size, free_space);
997 
998 #ifdef CONFIG_REISERFS_CHECK
999         if (zeros_number > paste_size) {
1000                 struct super_block *sb = NULL;
1001                 if (bi && bi->tb)
1002                         sb = bi->tb->tb_sb;
1003                 print_cur_tb("10177");
1004                 reiserfs_panic(sb, "vs-10177",
1005                                "zeros_number == %d, paste_size == %d",
1006                                zeros_number, paste_size);
1007         }
1008 #endif                          /* CONFIG_REISERFS_CHECK */
1009 
1010         /* item to be appended */
1011         ih = item_head(bh, affected_item_num);
1012 
1013         last_loc = ih_location(&ih[nr - affected_item_num - 1]);
1014         unmoved_loc = affected_item_num ? ih_location(ih - 1) : bh->b_size;
1015 
1016         /* prepare space */
1017         memmove(bh->b_data + last_loc - paste_size, bh->b_data + last_loc,
1018                 unmoved_loc - last_loc);
1019 
1020         /* change locations */
1021         for (i = affected_item_num; i < nr; i++)
1022                 put_ih_location(&ih[i - affected_item_num],
1023                                 ih_location(&ih[i - affected_item_num]) -
1024                                 paste_size);
1025 
1026         if (body) {
1027                 if (!is_direntry_le_ih(ih)) {
1028                         if (!pos_in_item) {
1029                                 /* shift data to right */
1030                                 memmove(bh->b_data + ih_location(ih) +
1031                                         paste_size,
1032                                         bh->b_data + ih_location(ih),
1033                                         ih_item_len(ih));
1034                                 /* paste data in the head of item */
1035                                 memset(bh->b_data + ih_location(ih), 0,
1036                                        zeros_number);
1037                                 memcpy(bh->b_data + ih_location(ih) +
1038                                        zeros_number, body,
1039                                        paste_size - zeros_number);
1040                         } else {
1041                                 memset(bh->b_data + unmoved_loc - paste_size, 0,
1042                                        zeros_number);
1043                                 memcpy(bh->b_data + unmoved_loc - paste_size +
1044                                        zeros_number, body,
1045                                        paste_size - zeros_number);
1046                         }
1047                 }
1048         } else
1049                 memset(bh->b_data + unmoved_loc - paste_size, '\0', paste_size);
1050 
1051         put_ih_item_len(ih, ih_item_len(ih) + paste_size);
1052 
1053         /* change free space */
1054         set_blkh_free_space(blkh, free_space - paste_size);
1055 
1056         do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1057 
1058         if (bi->bi_parent) {
1059                 struct disk_child *t_dc =
1060                     B_N_CHILD(bi->bi_parent, bi->bi_position);
1061                 put_dc_size(t_dc, dc_size(t_dc) + paste_size);
1062                 do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1063         }
1064 }
1065 
1066 /*
1067  * cuts DEL_COUNT entries beginning from FROM-th entry. Directory item
1068  * does not have free space, so it moves DEHs and remaining records as
1069  * necessary. Return value is size of removed part of directory item
1070  * in bytes.
1071  */
1072 static int leaf_cut_entries(struct buffer_head *bh,
1073                             struct item_head *ih, int from, int del_count)
1074 {
1075         char *item;
1076         struct reiserfs_de_head *deh;
1077         int prev_record_offset; /* offset of record, that is (from-1)th */
1078         char *prev_record;      /* */
1079         int cut_records_len;    /* length of all removed records */
1080         int i;
1081 
1082         /*
1083          * make sure that item is directory and there are enough entries to
1084          * remove
1085          */
1086         RFALSE(!is_direntry_le_ih(ih), "10180: item is not directory item");
1087         RFALSE(ih_entry_count(ih) < from + del_count,
1088                "10185: item contains not enough entries: entry_count = %d, from = %d, to delete = %d",
1089                ih_entry_count(ih), from, del_count);
1090 
1091         if (del_count == 0)
1092                 return 0;
1093 
1094         /* first byte of item */
1095         item = bh->b_data + ih_location(ih);
1096 
1097         /* entry head array */
1098         deh = B_I_DEH(bh, ih);
1099 
1100         /*
1101          * first byte of remaining entries, those are BEFORE cut entries
1102          * (prev_record) and length of all removed records (cut_records_len)
1103          */
1104         prev_record_offset =
1105             (from ? deh_location(&deh[from - 1]) : ih_item_len(ih));
1106         cut_records_len = prev_record_offset /*from_record */  -
1107             deh_location(&deh[from + del_count - 1]);
1108         prev_record = item + prev_record_offset;
1109 
1110         /* adjust locations of remaining entries */
1111         for (i = ih_entry_count(ih) - 1; i > from + del_count - 1; i--)
1112                 put_deh_location(&deh[i],
1113                                  deh_location(&deh[i]) -
1114                                  (DEH_SIZE * del_count));
1115 
1116         for (i = 0; i < from; i++)
1117                 put_deh_location(&deh[i],
1118                                  deh_location(&deh[i]) - (DEH_SIZE * del_count +
1119                                                           cut_records_len));
1120 
1121         put_ih_entry_count(ih, ih_entry_count(ih) - del_count);
1122 
1123         /* shift entry head array and entries those are AFTER removed entries */
1124         memmove((char *)(deh + from),
1125                 deh + from + del_count,
1126                 prev_record - cut_records_len - (char *)(deh + from +
1127                                                          del_count));
1128 
1129         /* shift records, those are BEFORE removed entries */
1130         memmove(prev_record - cut_records_len - DEH_SIZE * del_count,
1131                 prev_record, item + ih_item_len(ih) - prev_record);
1132 
1133         return DEH_SIZE * del_count + cut_records_len;
1134 }
1135 
1136 /*
1137  * when cut item is part of regular file
1138  *      pos_in_item - first byte that must be cut
1139  *      cut_size - number of bytes to be cut beginning from pos_in_item
1140  *
1141  * when cut item is part of directory
1142  *      pos_in_item - number of first deleted entry
1143  *      cut_size - count of deleted entries
1144  */
1145 void leaf_cut_from_buffer(struct buffer_info *bi, int cut_item_num,
1146                           int pos_in_item, int cut_size)
1147 {
1148         int nr;
1149         struct buffer_head *bh = bi->bi_bh;
1150         struct block_head *blkh;
1151         struct item_head *ih;
1152         int last_loc, unmoved_loc;
1153         int i;
1154 
1155         blkh = B_BLK_HEAD(bh);
1156         nr = blkh_nr_item(blkh);
1157 
1158         /* item head of truncated item */
1159         ih = item_head(bh, cut_item_num);
1160 
1161         if (is_direntry_le_ih(ih)) {
1162                 /* first cut entry () */
1163                 cut_size = leaf_cut_entries(bh, ih, pos_in_item, cut_size);
1164                 if (pos_in_item == 0) {
1165                         /* change key */
1166                         RFALSE(cut_item_num,
1167                                "when 0-th enrty of item is cut, that item must be first in the node, not %d-th",
1168                                cut_item_num);
1169                         /* change item key by key of first entry in the item */
1170                         set_le_ih_k_offset(ih, deh_offset(B_I_DEH(bh, ih)));
1171                 }
1172         } else {
1173                 /* item is direct or indirect */
1174                 RFALSE(is_statdata_le_ih(ih), "10195: item is stat data");
1175                 RFALSE(pos_in_item && pos_in_item + cut_size != ih_item_len(ih),
1176                        "10200: invalid offset (%lu) or trunc_size (%lu) or ih_item_len (%lu)",
1177                        (long unsigned)pos_in_item, (long unsigned)cut_size,
1178                        (long unsigned)ih_item_len(ih));
1179 
1180                 /* shift item body to left if cut is from the head of item */
1181                 if (pos_in_item == 0) {
1182                         memmove(bh->b_data + ih_location(ih),
1183                                 bh->b_data + ih_location(ih) + cut_size,
1184                                 ih_item_len(ih) - cut_size);
1185 
1186                         /* change key of item */
1187                         if (is_direct_le_ih(ih))
1188                                 set_le_ih_k_offset(ih,
1189                                                    le_ih_k_offset(ih) +
1190                                                    cut_size);
1191                         else {
1192                                 set_le_ih_k_offset(ih,
1193                                                    le_ih_k_offset(ih) +
1194                                                    (cut_size / UNFM_P_SIZE) *
1195                                                    bh->b_size);
1196                                 RFALSE(ih_item_len(ih) == cut_size
1197                                        && get_ih_free_space(ih),
1198                                        "10205: invalid ih_free_space (%h)", ih);
1199                         }
1200                 }
1201         }
1202 
1203         /* location of the last item */
1204         last_loc = ih_location(&ih[nr - cut_item_num - 1]);
1205 
1206         /* location of the item, which is remaining at the same place */
1207         unmoved_loc = cut_item_num ? ih_location(ih - 1) : bh->b_size;
1208 
1209         /* shift */
1210         memmove(bh->b_data + last_loc + cut_size, bh->b_data + last_loc,
1211                 unmoved_loc - last_loc - cut_size);
1212 
1213         /* change item length */
1214         put_ih_item_len(ih, ih_item_len(ih) - cut_size);
1215 
1216         if (is_indirect_le_ih(ih)) {
1217                 if (pos_in_item)
1218                         set_ih_free_space(ih, 0);
1219         }
1220 
1221         /* change locations */
1222         for (i = cut_item_num; i < nr; i++)
1223                 put_ih_location(&ih[i - cut_item_num],
1224                                 ih_location(&ih[i - cut_item_num]) + cut_size);
1225 
1226         /* size, free space */
1227         set_blkh_free_space(blkh, blkh_free_space(blkh) + cut_size);
1228 
1229         do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1230 
1231         if (bi->bi_parent) {
1232                 struct disk_child *t_dc;
1233                 t_dc = B_N_CHILD(bi->bi_parent, bi->bi_position);
1234                 put_dc_size(t_dc, dc_size(t_dc) - cut_size);
1235                 do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1236         }
1237 }
1238 
1239 /* delete del_num items from buffer starting from the first'th item */
1240 static void leaf_delete_items_entirely(struct buffer_info *bi,
1241                                        int first, int del_num)
1242 {
1243         struct buffer_head *bh = bi->bi_bh;
1244         int nr;
1245         int i, j;
1246         int last_loc, last_removed_loc;
1247         struct block_head *blkh;
1248         struct item_head *ih;
1249 
1250         RFALSE(bh == NULL, "10210: buffer is 0");
1251         RFALSE(del_num < 0, "10215: del_num less than 0 (%d)", del_num);
1252 
1253         if (del_num == 0)
1254                 return;
1255 
1256         blkh = B_BLK_HEAD(bh);
1257         nr = blkh_nr_item(blkh);
1258 
1259         RFALSE(first < 0 || first + del_num > nr,
1260                "10220: first=%d, number=%d, there is %d items", first, del_num,
1261                nr);
1262 
1263         if (first == 0 && del_num == nr) {
1264                 /* this does not work */
1265                 make_empty_node(bi);
1266 
1267                 do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1268                 return;
1269         }
1270 
1271         ih = item_head(bh, first);
1272 
1273         /* location of unmovable item */
1274         j = (first == 0) ? bh->b_size : ih_location(ih - 1);
1275 
1276         /* delete items */
1277         last_loc = ih_location(&ih[nr - 1 - first]);
1278         last_removed_loc = ih_location(&ih[del_num - 1]);
1279 
1280         memmove(bh->b_data + last_loc + j - last_removed_loc,
1281                 bh->b_data + last_loc, last_removed_loc - last_loc);
1282 
1283         /* delete item headers */
1284         memmove(ih, ih + del_num, (nr - first - del_num) * IH_SIZE);
1285 
1286         /* change item location */
1287         for (i = first; i < nr - del_num; i++)
1288                 put_ih_location(&ih[i - first],
1289                                 ih_location(&ih[i - first]) + (j -
1290                                                                  last_removed_loc));
1291 
1292         /* sizes, item number */
1293         set_blkh_nr_item(blkh, blkh_nr_item(blkh) - del_num);
1294         set_blkh_free_space(blkh,
1295                             blkh_free_space(blkh) + (j - last_removed_loc +
1296                                                      IH_SIZE * del_num));
1297 
1298         do_balance_mark_leaf_dirty(bi->tb, bh, 0);
1299 
1300         if (bi->bi_parent) {
1301                 struct disk_child *t_dc =
1302                     B_N_CHILD(bi->bi_parent, bi->bi_position);
1303                 put_dc_size(t_dc,
1304                             dc_size(t_dc) - (j - last_removed_loc +
1305                                              IH_SIZE * del_num));
1306                 do_balance_mark_internal_dirty(bi->tb, bi->bi_parent, 0);
1307         }
1308 }
1309 
1310 /*
1311  * paste new_entry_count entries (new_dehs, records) into position
1312  * before to item_num-th item
1313  */
1314 void leaf_paste_entries(struct buffer_info *bi,
1315                         int item_num,
1316                         int before,
1317                         int new_entry_count,
1318                         struct reiserfs_de_head *new_dehs,
1319                         const char *records, int paste_size)
1320 {
1321         struct item_head *ih;
1322         char *item;
1323         struct reiserfs_de_head *deh;
1324         char *insert_point;
1325         int i;
1326         struct buffer_head *bh = bi->bi_bh;
1327 
1328         if (new_entry_count == 0)
1329                 return;
1330 
1331         ih = item_head(bh, item_num);
1332 
1333         /*
1334          * make sure, that item is directory, and there are enough
1335          * records in it
1336          */
1337         RFALSE(!is_direntry_le_ih(ih), "10225: item is not directory item");
1338         RFALSE(ih_entry_count(ih) < before,
1339                "10230: there are no entry we paste entries before. entry_count = %d, before = %d",
1340                ih_entry_count(ih), before);
1341 
1342         /* first byte of dest item */
1343         item = bh->b_data + ih_location(ih);
1344 
1345         /* entry head array */
1346         deh = B_I_DEH(bh, ih);
1347 
1348         /* new records will be pasted at this point */
1349         insert_point =
1350             item +
1351             (before ? deh_location(&deh[before - 1])
1352              : (ih_item_len(ih) - paste_size));
1353 
1354         /* adjust locations of records that will be AFTER new records */
1355         for (i = ih_entry_count(ih) - 1; i >= before; i--)
1356                 put_deh_location(&deh[i],
1357                                  deh_location(&deh[i]) +
1358                                  (DEH_SIZE * new_entry_count));
1359 
1360         /* adjust locations of records that will be BEFORE new records */
1361         for (i = 0; i < before; i++)
1362                 put_deh_location(&deh[i],
1363                                  deh_location(&deh[i]) + paste_size);
1364 
1365         put_ih_entry_count(ih, ih_entry_count(ih) + new_entry_count);
1366 
1367         /* prepare space for pasted records */
1368         memmove(insert_point + paste_size, insert_point,
1369                 item + (ih_item_len(ih) - paste_size) - insert_point);
1370 
1371         /* copy new records */
1372         memcpy(insert_point + DEH_SIZE * new_entry_count, records,
1373                paste_size - DEH_SIZE * new_entry_count);
1374 
1375         /* prepare space for new entry heads */
1376         deh += before;
1377         memmove((char *)(deh + new_entry_count), deh,
1378                 insert_point - (char *)deh);
1379 
1380         /* copy new entry heads */
1381         deh = (struct reiserfs_de_head *)((char *)deh);
1382         memcpy(deh, new_dehs, DEH_SIZE * new_entry_count);
1383 
1384         /* set locations of new records */
1385         for (i = 0; i < new_entry_count; i++) {
1386                 put_deh_location(&deh[i],
1387                                  deh_location(&deh[i]) +
1388                                  (-deh_location
1389                                   (&new_dehs[new_entry_count - 1]) +
1390                                   insert_point + DEH_SIZE * new_entry_count -
1391                                   item));
1392         }
1393 
1394         /* change item key if necessary (when we paste before 0-th entry */
1395         if (!before) {
1396                 set_le_ih_k_offset(ih, deh_offset(new_dehs));
1397         }
1398 #ifdef CONFIG_REISERFS_CHECK
1399         {
1400                 int prev, next;
1401                 /* check record locations */
1402                 deh = B_I_DEH(bh, ih);
1403                 for (i = 0; i < ih_entry_count(ih); i++) {
1404                         next =
1405                             (i <
1406                              ih_entry_count(ih) -
1407                              1) ? deh_location(&deh[i + 1]) : 0;
1408                         prev = (i != 0) ? deh_location(&deh[i - 1]) : 0;
1409 
1410                         if (prev && prev <= deh_location(&deh[i]))
1411                                 reiserfs_error(sb_from_bi(bi), "vs-10240",
1412                                                "directory item (%h) "
1413                                                "corrupted (prev %a, "
1414                                                "cur(%d) %a)",
1415                                                ih, deh + i - 1, i, deh + i);
1416                         if (next && next >= deh_location(&deh[i]))
1417                                 reiserfs_error(sb_from_bi(bi), "vs-10250",
1418                                                "directory item (%h) "
1419                                                "corrupted (cur(%d) %a, "
1420                                                "next %a)",
1421                                                ih, i, deh + i, deh + i + 1);
1422                 }
1423         }
1424 #endif
1425 
1426 }
1427 

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