2 * extent.c --- routines to implement extents support
4 * Copyright (C) 2007 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
25 #include <sys/types.h>
33 * Definitions to be dropped in lib/ext2fs/ext2fs.h
52 struct ext2_extent_handle {
56 struct ext2_inode *inode;
57 struct ext2_inode inodebuf;
61 struct extent_path *path;
64 struct ext2_extent_path {
71 * Useful Debugging stuff
75 static void dbg_show_header(struct ext3_extent_header *eh)
77 printf("header: magic=%x entries=%u max=%u depth=%u generation=%u\n",
78 ext2fs_le16_to_cpu(eh->eh_magic),
79 ext2fs_le16_to_cpu(eh->eh_entries),
80 ext2fs_le16_to_cpu(eh->eh_max),
81 ext2fs_le16_to_cpu(eh->eh_depth),
82 ext2fs_le32_to_cpu(eh->eh_generation));
85 static void dbg_show_index(struct ext3_extent_idx *ix)
87 printf("index: block=%u leaf=%u leaf_hi=%u unused=%u\n",
88 ext2fs_le32_to_cpu(ix->ei_block),
89 ext2fs_le32_to_cpu(ix->ei_leaf),
90 ext2fs_le16_to_cpu(ix->ei_leaf_hi),
91 ext2fs_le16_to_cpu(ix->ei_unused));
94 static void dbg_show_extent(struct ext3_extent *ex)
96 printf("extent: block=%u-%u len=%u start=%u start_hi=%u\n",
97 ext2fs_le32_to_cpu(ex->ee_block),
98 ext2fs_le32_to_cpu(ex->ee_block) +
99 ext2fs_le16_to_cpu(ex->ee_len) - 1,
100 ext2fs_le16_to_cpu(ex->ee_len),
101 ext2fs_le32_to_cpu(ex->ee_start),
102 ext2fs_le16_to_cpu(ex->ee_start_hi));
105 static void dbg_print_extent(char *desc, struct ext2fs_extent *extent)
108 printf("%s: ", desc);
109 printf("extent: lblk %llu--%llu, len %u, pblk %llu, flags: ",
110 extent->e_lblk, extent->e_lblk + extent->e_len - 1,
111 extent->e_len, extent->e_pblk);
112 if (extent->e_flags & EXT2_EXTENT_FLAGS_LEAF)
113 fputs("LEAF ", stdout);
114 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT)
115 fputs("UNINIT ", stdout);
116 if (extent->e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)
117 fputs("2ND_VISIT ", stdout);
118 if (!extent->e_flags)
119 fputs("(none)", stdout);
125 #define dbg_show_header(eh) do { } while (0)
126 #define dbg_show_index(ix) do { } while (0)
127 #define dbg_show_extent(ex) do { } while (0)
128 #define dbg_print_extent(desc, ex) do { } while (0)
132 * Verify the extent header as being sane
134 errcode_t ext2fs_extent_header_verify(void *ptr, int size)
136 int eh_max, entry_size;
137 struct ext3_extent_header *eh = ptr;
140 if (ext2fs_le16_to_cpu(eh->eh_magic) != EXT3_EXT_MAGIC)
141 return EXT2_ET_EXTENT_HEADER_BAD;
142 if (ext2fs_le16_to_cpu(eh->eh_entries) > ext2fs_le16_to_cpu(eh->eh_max))
143 return EXT2_ET_EXTENT_HEADER_BAD;
144 if (eh->eh_depth == 0)
145 entry_size = sizeof(struct ext3_extent);
147 entry_size = sizeof(struct ext3_extent_idx);
149 eh_max = (size - sizeof(*eh)) / entry_size;
150 /* Allow two extent-sized items at the end of the block, for
151 * ext4_extent_tail with checksum in the future. */
152 if ((ext2fs_le16_to_cpu(eh->eh_max) > eh_max) ||
153 (ext2fs_le16_to_cpu(eh->eh_max) < (eh_max - 2)))
154 return EXT2_ET_EXTENT_HEADER_BAD;
161 * Begin functions to handle an inode's extent information
163 void ext2fs_extent_free(ext2_extent_handle_t handle)
171 for (i=1; i <= handle->max_depth; i++) {
172 if (handle->path[i].buf)
173 ext2fs_free_mem(&handle->path[i].buf);
175 ext2fs_free_mem(&handle->path);
177 ext2fs_free_mem(&handle);
180 errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino,
181 ext2_extent_handle_t *ret_handle)
183 return ext2fs_extent_open2(fs, ino, NULL, ret_handle);
186 errcode_t ext2fs_extent_open2(ext2_filsys fs, ext2_ino_t ino,
187 struct ext2_inode *inode,
188 ext2_extent_handle_t *ret_handle)
190 struct ext2_extent_handle *handle;
193 struct ext3_extent_header *eh;
195 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
198 if ((ino == 0) || (ino > fs->super->s_inodes_count))
199 return EXT2_ET_BAD_INODE_NUM;
201 retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle);
204 memset(handle, 0, sizeof(struct ext2_extent_handle));
210 handle->inode = inode;
212 handle->inode = &handle->inodebuf;
213 retval = ext2fs_read_inode(fs, ino, handle->inode);
218 eh = (struct ext3_extent_header *) &handle->inode->i_block[0];
220 for (i=0; i < EXT2_N_BLOCKS; i++)
221 if (handle->inode->i_block[i])
223 if (i >= EXT2_N_BLOCKS) {
224 eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC);
227 i = (sizeof(handle->inode->i_block) - sizeof(*eh)) /
228 sizeof(struct ext3_extent);
229 eh->eh_max = ext2fs_cpu_to_le16(i);
230 handle->inode->i_flags |= EXT4_EXTENTS_FL;
233 if (!(handle->inode->i_flags & EXT4_EXTENTS_FL)) {
234 retval = EXT2_ET_INODE_NOT_EXTENT;
238 retval = ext2fs_extent_header_verify(eh, sizeof(handle->inode->i_block));
242 handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth);
243 handle->type = ext2fs_le16_to_cpu(eh->eh_magic);
245 retval = ext2fs_get_mem(((handle->max_depth+1) *
246 sizeof(struct extent_path)),
248 memset(handle->path, 0,
249 (handle->max_depth+1) * sizeof(struct extent_path));
250 handle->path[0].buf = (char *) handle->inode->i_block;
252 handle->path[0].left = handle->path[0].entries =
253 ext2fs_le16_to_cpu(eh->eh_entries);
254 handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max);
255 handle->path[0].curr = 0;
256 handle->path[0].end_blk =
257 (EXT2_I_SIZE(handle->inode) + fs->blocksize - 1) >>
258 EXT2_BLOCK_SIZE_BITS(fs->super);
259 handle->path[0].visit_num = 1;
261 handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE;
263 *ret_handle = handle;
267 ext2fs_extent_free(handle);
272 * This function is responsible for (optionally) moving through the
273 * extent tree and then returning the current extent
275 errcode_t ext2fs_extent_get(ext2_extent_handle_t handle,
276 int flags, struct ext2fs_extent *extent)
278 struct extent_path *path, *newpath;
279 struct ext3_extent_header *eh;
280 struct ext3_extent_idx *ix = 0;
281 struct ext3_extent *ex;
287 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
290 return EXT2_ET_NO_CURRENT_NODE;
292 orig_op = op = flags & EXT2_EXTENT_MOVE_MASK;
295 path = handle->path + handle->level;
296 if ((orig_op == EXT2_EXTENT_NEXT) ||
297 (orig_op == EXT2_EXTENT_NEXT_LEAF)) {
298 if (handle->level < handle->max_depth) {
300 if (path->visit_num == 0) {
302 op = EXT2_EXTENT_DOWN;
303 } else if (path->left > 0)
304 op = EXT2_EXTENT_NEXT_SIB;
305 else if (handle->level > 0)
308 return EXT2_ET_EXTENT_NO_NEXT;
312 op = EXT2_EXTENT_NEXT_SIB;
313 else if (handle->level > 0)
316 return EXT2_ET_EXTENT_NO_NEXT;
318 if (op != EXT2_EXTENT_NEXT_SIB) {
319 #ifdef DEBUG_GET_EXTENT
320 printf("<<<< OP = %s\n",
321 (op == EXT2_EXTENT_DOWN) ? "down" :
322 ((op == EXT2_EXTENT_UP) ? "up" : "unknown"));
327 if ((orig_op == EXT2_EXTENT_PREV) ||
328 (orig_op == EXT2_EXTENT_PREV_LEAF)) {
329 if (handle->level < handle->max_depth) {
331 if (path->visit_num > 0 ) {
332 /* path->visit_num = 0; */
333 op = EXT2_EXTENT_DOWN_AND_LAST;
334 } else if (path->left < path->entries-1)
335 op = EXT2_EXTENT_PREV_SIB;
336 else if (handle->level > 0)
339 return EXT2_ET_EXTENT_NO_PREV;
342 if (path->left < path->entries-1)
343 op = EXT2_EXTENT_PREV_SIB;
344 else if (handle->level > 0)
347 return EXT2_ET_EXTENT_NO_PREV;
349 if (op != EXT2_EXTENT_PREV_SIB) {
350 #ifdef DEBUG_GET_EXTENT
351 printf("<<<< OP = %s\n",
352 (op == EXT2_EXTENT_DOWN_AND_LAST) ? "down/last" :
353 ((op == EXT2_EXTENT_UP) ? "up" : "unknown"));
358 if (orig_op == EXT2_EXTENT_LAST_LEAF) {
359 if ((handle->level < handle->max_depth) &&
361 op = EXT2_EXTENT_DOWN;
363 op = EXT2_EXTENT_LAST_SIB;
364 #ifdef DEBUG_GET_EXTENT
365 printf("<<<< OP = %s\n",
366 (op == EXT2_EXTENT_DOWN) ? "down" : "last_sib");
371 case EXT2_EXTENT_CURRENT:
374 case EXT2_EXTENT_ROOT:
376 path = handle->path + handle->level;
378 case EXT2_EXTENT_FIRST_SIB:
379 path->left = path->entries;
382 case EXT2_EXTENT_NEXT_SIB:
384 return EXT2_ET_EXTENT_NO_NEXT;
389 eh = (struct ext3_extent_header *) path->buf;
390 ix = EXT_FIRST_INDEX(eh);
396 case EXT2_EXTENT_PREV_SIB:
398 path->left+1 >= path->entries)
399 return EXT2_ET_EXTENT_NO_PREV;
404 if (handle->level < handle->max_depth)
407 case EXT2_EXTENT_LAST_SIB:
408 eh = (struct ext3_extent_header *) path->buf;
409 path->curr = EXT_LAST_EXTENT(eh);
415 if (handle->level <= 0)
416 return EXT2_ET_EXTENT_NO_UP;
420 if ((orig_op == EXT2_EXTENT_PREV) ||
421 (orig_op == EXT2_EXTENT_PREV_LEAF))
424 case EXT2_EXTENT_DOWN:
425 case EXT2_EXTENT_DOWN_AND_LAST:
426 if (!path->curr ||(handle->level >= handle->max_depth))
427 return EXT2_ET_EXTENT_NO_DOWN;
432 retval = ext2fs_get_mem(handle->fs->blocksize,
437 blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
438 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
439 if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) &&
440 (handle->fs->io != handle->fs->image_io))
441 memset(newpath->buf, 0, handle->fs->blocksize);
443 retval = io_channel_read_blk64(handle->fs->io,
444 blk, 1, newpath->buf);
450 eh = (struct ext3_extent_header *) newpath->buf;
452 retval = ext2fs_extent_header_verify(eh, handle->fs->blocksize);
458 newpath->left = newpath->entries =
459 ext2fs_le16_to_cpu(eh->eh_entries);
460 newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max);
462 if (path->left > 0) {
464 newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block);
466 newpath->end_blk = path->end_blk;
469 if (op == EXT2_EXTENT_DOWN) {
470 ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh);
472 path->left = path->entries - 1;
475 ix = EXT_LAST_INDEX((struct ext3_extent_header *) eh);
478 if (handle->level < handle->max_depth)
481 #ifdef DEBUG_GET_EXTENT
482 printf("Down to level %d/%d, end_blk=%llu\n",
483 handle->level, handle->max_depth,
488 return EXT2_ET_OP_NOT_SUPPORTED;
492 return EXT2_ET_NO_CURRENT_NODE;
495 #ifdef DEBUG_GET_EXTENT
496 printf("(Left %d)\n", path->left);
499 if (handle->level == handle->max_depth) {
500 ex = (struct ext3_extent *) ix;
502 extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) +
503 ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32);
504 extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block);
505 extent->e_len = ext2fs_le16_to_cpu(ex->ee_len);
506 extent->e_flags |= EXT2_EXTENT_FLAGS_LEAF;
507 if (extent->e_len > EXT_INIT_MAX_LEN) {
508 extent->e_len -= EXT_INIT_MAX_LEN;
509 extent->e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
512 extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) +
513 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
514 extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block);
515 if (path->left > 0) {
517 end_blk = ext2fs_le32_to_cpu(ix->ei_block);
519 end_blk = path->end_blk;
521 extent->e_len = end_blk - extent->e_lblk;
524 extent->e_flags |= EXT2_EXTENT_FLAGS_SECOND_VISIT;
526 if (((orig_op == EXT2_EXTENT_NEXT_LEAF) ||
527 (orig_op == EXT2_EXTENT_PREV_LEAF)) &&
528 (handle->level != handle->max_depth))
531 if ((orig_op == EXT2_EXTENT_LAST_LEAF) &&
532 ((handle->level != handle->max_depth) ||
539 static errcode_t update_path(ext2_extent_handle_t handle)
543 struct ext3_extent_idx *ix;
545 if (handle->level == 0) {
546 retval = ext2fs_write_inode(handle->fs, handle->ino,
549 ix = handle->path[handle->level - 1].curr;
550 blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
551 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
553 retval = io_channel_write_blk64(handle->fs->io,
554 blk, 1, handle->path[handle->level].buf);
560 errcode_t ext2fs_extent_save_path(ext2_extent_handle_t handle,
561 ext2_extent_path_t *ret_path)
563 ext2_extent_path_t save_path;
564 struct ext2fs_extent extent;
565 struct ext2_extent_info info;
568 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
572 retval = ext2fs_extent_get_info(handle, &info);
576 retval = ext2fs_get_mem(sizeof(struct ext2_extent_path), &save_path);
579 memset(save_path, 0, sizeof(struct ext2_extent_path));
581 save_path->magic = EXT2_ET_MAGIC_EXTENT_PATH;
582 save_path->leaf_height = info.max_depth - info.curr_level - 1;
583 save_path->lblk = extent.e_lblk;
585 *ret_path = save_path;
589 errcode_t ext2fs_extent_free_path(ext2_extent_path_t path)
591 EXT2_CHECK_MAGIC(path, EXT2_ET_MAGIC_EXTENT_PATH);
593 ext2fs_free_mem(&path);
599 * Go to the node at leaf_level which contains logical block blk.
601 * leaf_level is height from the leaf node level, i.e.
602 * leaf_level 0 is at leaf node, leaf_level 1 is 1 above etc.
604 * If "blk" has no mapping (hole) then handle is left at last
607 errcode_t ext2fs_extent_goto2(ext2_extent_handle_t handle,
608 int leaf_level, blk64_t blk)
610 struct ext2fs_extent extent;
613 retval = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent);
615 if (retval == EXT2_ET_EXTENT_NO_NEXT)
616 retval = EXT2_ET_EXTENT_NOT_FOUND;
620 if (leaf_level > handle->max_depth) {
622 printf("leaf level %d greater than tree depth %d\n",
623 leaf_level, handle->max_depth);
625 return EXT2_ET_OP_NOT_SUPPORTED;
629 printf("goto extent ino %u, level %d, %llu\n", handle->ino,
633 #ifdef DEBUG_GOTO_EXTENTS
634 dbg_print_extent("root", &extent);
637 if (handle->max_depth - handle->level == leaf_level) {
638 /* block is in this &extent */
639 if ((blk >= extent.e_lblk) &&
640 (blk < extent.e_lblk + extent.e_len))
642 if (blk < extent.e_lblk) {
643 retval = ext2fs_extent_get(handle,
644 EXT2_EXTENT_PREV_SIB,
646 return EXT2_ET_EXTENT_NOT_FOUND;
648 retval = ext2fs_extent_get(handle,
649 EXT2_EXTENT_NEXT_SIB,
651 if (retval == EXT2_ET_EXTENT_NO_NEXT)
652 return EXT2_ET_EXTENT_NOT_FOUND;
658 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_SIB,
660 if (retval == EXT2_ET_EXTENT_NO_NEXT)
665 #ifdef DEBUG_GOTO_EXTENTS
666 dbg_print_extent("next", &extent);
668 if (blk == extent.e_lblk)
670 if (blk > extent.e_lblk)
673 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_SIB,
678 #ifdef DEBUG_GOTO_EXTENTS
679 dbg_print_extent("prev", &extent);
683 retval = ext2fs_extent_get(handle, EXT2_EXTENT_DOWN,
688 #ifdef DEBUG_GOTO_EXTENTS
689 dbg_print_extent("down", &extent);
694 errcode_t ext2fs_extent_goto(ext2_extent_handle_t handle,
697 return ext2fs_extent_goto2(handle, 0, blk);
701 * Traverse back up to root fixing parents of current node as needed.
703 * If we changed start of first entry in a node, fix parent index start
706 * Safe to call for any position in node; if not at the first entry,
707 * will simply return.
709 errcode_t ext2fs_extent_fix_parents(ext2_extent_handle_t handle)
714 struct extent_path *path;
715 struct ext2fs_extent extent;
716 struct ext2_extent_info info;
718 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
720 if (!(handle->fs->flags & EXT2_FLAG_RW))
721 return EXT2_ET_RO_FILSYS;
724 return EXT2_ET_NO_CURRENT_NODE;
726 path = handle->path + handle->level;
728 return EXT2_ET_NO_CURRENT_NODE;
730 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
734 /* modified node's start block */
735 start = extent.e_lblk;
737 if ((retval = ext2fs_extent_get_info(handle, &info)))
739 orig_height = info.max_depth - info.curr_level;
741 /* traverse up until index not first, or startblk matches, or top */
742 while (handle->level > 0 &&
743 (path->left == path->entries - 1)) {
744 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
747 if (extent.e_lblk == start)
749 path = handle->path + handle->level;
750 extent.e_len += (extent.e_lblk - start);
751 extent.e_lblk = start;
752 retval = ext2fs_extent_replace(handle, 0, &extent);
758 /* put handle back to where we started */
759 retval = ext2fs_extent_goto2(handle, orig_height, start);
764 errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle,
765 int flags EXT2FS_ATTR((unused)),
766 struct ext2fs_extent *extent)
768 struct extent_path *path;
769 struct ext3_extent_idx *ix;
770 struct ext3_extent *ex;
772 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
774 if (!(handle->fs->flags & EXT2_FLAG_RW))
775 return EXT2_ET_RO_FILSYS;
778 return EXT2_ET_NO_CURRENT_NODE;
780 path = handle->path + handle->level;
782 return EXT2_ET_NO_CURRENT_NODE;
785 printf("extent replace: %u ", handle->ino);
786 dbg_print_extent(0, extent);
789 if (handle->level == handle->max_depth) {
792 ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk);
793 ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
794 ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
795 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT) {
796 if (extent->e_len > EXT_UNINIT_MAX_LEN)
797 return EXT2_ET_EXTENT_INVALID_LENGTH;
798 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len +
801 if (extent->e_len > EXT_INIT_MAX_LEN)
802 return EXT2_ET_EXTENT_INVALID_LENGTH;
803 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len);
808 ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
809 ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
810 ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk);
818 * allocate a new block, move half the current node to it, and update parent
820 * handle will be left pointing at original record.
822 errcode_t ext2fs_extent_node_split(ext2_extent_handle_t handle)
824 errcode_t retval = 0;
825 blk64_t new_node_pblk;
826 blk64_t new_node_start;
828 blk64_t goal_blk = 0;
830 char *block_buf = NULL;
831 struct ext2fs_extent extent;
832 struct extent_path *path, *newpath = 0;
833 struct ext3_extent_header *eh, *neweh;
836 struct ext2_extent_info info;
839 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
841 if (!(handle->fs->flags & EXT2_FLAG_RW))
842 return EXT2_ET_RO_FILSYS;
845 return EXT2_ET_NO_CURRENT_NODE;
848 printf("splitting node at level %d\n", handle->level);
850 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
854 retval = ext2fs_extent_get_info(handle, &info);
858 /* save the position we were originally splitting... */
859 orig_height = info.max_depth - info.curr_level;
860 orig_lblk = extent.e_lblk;
862 /* Is there room in the parent for a new entry? */
864 (handle->path[handle->level - 1].entries >=
865 handle->path[handle->level - 1].max_entries)) {
868 printf("parent level %d full; splitting it too\n",
871 /* split the parent */
872 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
875 goal_blk = extent.e_pblk;
877 retval = ext2fs_extent_node_split(handle);
881 /* get handle back to our original split position */
882 retval = ext2fs_extent_goto2(handle, orig_height, orig_lblk);
887 /* At this point, parent should have room for this split */
888 path = handle->path + handle->level;
890 return EXT2_ET_NO_CURRENT_NODE;
892 /* extent header of the current node we'll split */
893 eh = (struct ext3_extent_header *)path->buf;
895 /* splitting root level means moving them all out */
896 if (handle->level == 0) {
898 tocopy = ext2fs_le16_to_cpu(eh->eh_entries);
899 retval = ext2fs_get_mem(((handle->max_depth+2) *
900 sizeof(struct extent_path)),
905 ((handle->max_depth+2) * sizeof(struct extent_path)));
907 tocopy = ext2fs_le16_to_cpu(eh->eh_entries) / 2;
911 printf("will copy out %d of %d entries at level %d\n",
912 tocopy, ext2fs_le16_to_cpu(eh->eh_entries),
918 printf("Nothing to copy to new block!\n");
920 retval = EXT2_ET_CANT_SPLIT_EXTENT;
924 /* first we need a new block, or can do nothing. */
925 block_buf = malloc(handle->fs->blocksize);
932 dgrp_t group = ext2fs_group_of_ino(handle->fs, handle->ino);
933 __u8 log_flex = handle->fs->super->s_log_groups_per_flex;
936 group = group & ~((1 << (log_flex)) - 1);
937 goal_blk = ext2fs_group_first_block2(handle->fs, group);
939 retval = ext2fs_alloc_block2(handle->fs, goal_blk, block_buf,
945 printf("will copy to new node at block %lu\n",
946 (unsigned long) new_node_pblk);
949 /* Copy data into new block buffer */
950 /* First the header for the new block... */
951 neweh = (struct ext3_extent_header *) block_buf;
952 memcpy(neweh, eh, sizeof(struct ext3_extent_header));
953 neweh->eh_entries = ext2fs_cpu_to_le16(tocopy);
954 neweh->eh_max = ext2fs_cpu_to_le16((handle->fs->blocksize -
955 sizeof(struct ext3_extent_header)) /
956 sizeof(struct ext3_extent));
958 /* then the entries for the new block... */
959 memcpy(EXT_FIRST_INDEX(neweh),
960 EXT_FIRST_INDEX(eh) +
961 (ext2fs_le16_to_cpu(eh->eh_entries) - tocopy),
962 sizeof(struct ext3_extent_idx) * tocopy);
964 new_node_start = ext2fs_le32_to_cpu(EXT_FIRST_INDEX(neweh)->ei_block);
966 /* ...and write the new node block out to disk. */
967 retval = io_channel_write_blk64(handle->fs->io, new_node_pblk, 1,
973 /* OK! we've created the new node; now adjust the tree */
975 /* current path now has fewer active entries, we copied some out */
976 if (handle->level == 0) {
977 memcpy(newpath, path,
978 sizeof(struct extent_path) * (handle->max_depth+1));
979 handle->path = newpath;
983 path->left = path->max_entries - 1;
985 eh->eh_depth = ext2fs_cpu_to_le16(handle->max_depth);
987 path->entries -= tocopy;
988 path->left -= tocopy;
991 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
992 /* this writes out the node, incl. the modified header */
993 retval = update_path(handle);
997 /* now go up and insert/replace index for new node we created */
999 retval = ext2fs_extent_get(handle, EXT2_EXTENT_FIRST_SIB, &extent);
1003 extent.e_lblk = new_node_start;
1004 extent.e_pblk = new_node_pblk;
1005 extent.e_len = handle->path[0].end_blk - extent.e_lblk;
1006 retval = ext2fs_extent_replace(handle, 0, &extent);
1010 __u32 new_node_length;
1012 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
1013 /* will insert after this one; it's length is shorter now */
1014 new_node_length = new_node_start - extent.e_lblk;
1015 extent.e_len -= new_node_length;
1016 retval = ext2fs_extent_replace(handle, 0, &extent);
1020 /* now set up the new extent and insert it */
1021 extent.e_lblk = new_node_start;
1022 extent.e_pblk = new_node_pblk;
1023 extent.e_len = new_node_length;
1024 retval = ext2fs_extent_insert(handle, EXT2_EXTENT_INSERT_AFTER, &extent);
1029 /* get handle back to our original position */
1030 retval = ext2fs_extent_goto2(handle, orig_height, orig_lblk);
1034 /* new node hooked in, so update inode block count (do this here?) */
1035 handle->inode->i_blocks += (handle->fs->blocksize *
1036 EXT2FS_CLUSTER_RATIO(handle->fs)) / 512;
1037 retval = ext2fs_write_inode(handle->fs, handle->ino,
1044 ext2fs_free_mem(&newpath);
1050 errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags,
1051 struct ext2fs_extent *extent)
1053 struct extent_path *path;
1054 struct ext3_extent_idx *ix;
1055 struct ext3_extent_header *eh;
1058 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1060 if (!(handle->fs->flags & EXT2_FLAG_RW))
1061 return EXT2_ET_RO_FILSYS;
1064 return EXT2_ET_NO_CURRENT_NODE;
1067 printf("extent insert: %u ", handle->ino);
1068 dbg_print_extent(0, extent);
1071 path = handle->path + handle->level;
1073 if (path->entries >= path->max_entries) {
1074 if (flags & EXT2_EXTENT_INSERT_NOSPLIT) {
1075 return EXT2_ET_CANT_INSERT_EXTENT;
1078 printf("node full (level %d) - splitting\n",
1081 retval = ext2fs_extent_node_split(handle);
1084 path = handle->path + handle->level;
1088 eh = (struct ext3_extent_header *) path->buf;
1091 if (flags & EXT2_EXTENT_INSERT_AFTER) {
1096 ix = EXT_FIRST_INDEX(eh);
1100 if (path->left >= 0)
1102 (path->left+1) * sizeof(struct ext3_extent_idx));
1106 eh = (struct ext3_extent_header *) path->buf;
1107 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
1109 retval = ext2fs_extent_replace(handle, 0, extent);
1113 retval = update_path(handle);
1120 ext2fs_extent_delete(handle, 0);
1125 * Sets the physical block for a logical file block in the extent tree.
1127 * May: map unmapped, unmap mapped, or remap mapped blocks.
1129 * Mapping an unmapped block adds a single-block extent.
1131 * Unmapping first or last block modifies extent in-place
1132 * - But may need to fix parent's starts too in first-block case
1134 * Mapping any unmapped block requires adding a (single-block) extent
1135 * and inserting into proper point in tree.
1137 * Modifying (unmapping or remapping) a block in the middle
1138 * of an extent requires splitting the extent.
1139 * - Remapping case requires new single-block extent.
1141 * Remapping first or last block adds an extent.
1143 * We really need extent adding to be smart about merging.
1146 errcode_t ext2fs_extent_set_bmap(ext2_extent_handle_t handle,
1147 blk64_t logical, blk64_t physical, int flags)
1149 errcode_t ec, retval = 0;
1150 int mapped = 1; /* logical is mapped? */
1152 int extent_uninit = 0;
1153 int prev_uninit = 0;
1154 int next_uninit = 0;
1156 int max_len = EXT_INIT_MAX_LEN;
1157 int has_prev, has_next;
1159 struct extent_path *path;
1160 struct ext2fs_extent extent, next_extent, prev_extent;
1161 struct ext2fs_extent newextent;
1162 struct ext2_extent_info info;
1164 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1167 printf("set_bmap ino %u log %lld phys %lld flags %d\n",
1168 handle->ino, logical, physical, flags);
1171 if (!(handle->fs->flags & EXT2_FLAG_RW))
1172 return EXT2_ET_RO_FILSYS;
1175 return EXT2_ET_NO_CURRENT_NODE;
1177 path = handle->path + handle->level;
1179 if (flags & EXT2_EXTENT_SET_BMAP_UNINIT) {
1181 max_len = EXT_UNINIT_MAX_LEN;
1184 /* if (re)mapping, set up new extent to insert */
1186 newextent.e_len = 1;
1187 newextent.e_pblk = physical;
1188 newextent.e_lblk = logical;
1189 newextent.e_flags = EXT2_EXTENT_FLAGS_LEAF;
1191 newextent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
1194 /* special case if the extent tree is completely empty */
1195 if ((handle->max_depth == 0) && (path->entries == 0)) {
1196 retval = ext2fs_extent_insert(handle, 0, &newextent);
1200 /* save our original location in the extent tree */
1201 if ((retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT,
1203 if (retval != EXT2_ET_NO_CURRENT_NODE)
1205 memset(&extent, 0, sizeof(extent));
1207 if ((retval = ext2fs_extent_get_info(handle, &info)))
1209 orig_height = info.max_depth - info.curr_level;
1210 orig_lblk = extent.e_lblk;
1212 /* go to the logical spot we want to (re/un)map */
1213 retval = ext2fs_extent_goto(handle, logical);
1215 if (retval == EXT2_ET_EXTENT_NOT_FOUND) {
1220 printf("block %llu already unmapped\n",
1230 * This may be the extent *before* the requested logical,
1231 * if it's currently unmapped.
1233 * Get the previous and next leaf extents, if they are present.
1235 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
1238 if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
1240 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_LEAF, &next_extent);
1243 if (retval != EXT2_ET_EXTENT_NO_NEXT)
1246 dbg_print_extent("set_bmap: next_extent",
1249 if (next_extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
1252 retval = ext2fs_extent_goto(handle, logical);
1253 if (retval && retval != EXT2_ET_EXTENT_NOT_FOUND)
1255 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_LEAF, &prev_extent);
1258 if (retval != EXT2_ET_EXTENT_NO_PREV)
1262 dbg_print_extent("set_bmap: prev_extent",
1264 if (prev_extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
1267 retval = ext2fs_extent_goto(handle, logical);
1268 if (retval && retval != EXT2_ET_EXTENT_NOT_FOUND)
1271 /* check if already pointing to the requested physical */
1272 if (mapped && (new_uninit == extent_uninit) &&
1273 (extent.e_pblk + (logical - extent.e_lblk) == physical)) {
1275 printf("physical block (at %llu) unchanged\n", logical);
1282 printf("mapping unmapped logical block %llu\n", logical);
1284 if ((logical == extent.e_lblk + extent.e_len) &&
1285 (physical == extent.e_pblk + extent.e_len) &&
1286 (new_uninit == extent_uninit) &&
1287 ((int) extent.e_len < max_len-1)) {
1289 retval = ext2fs_extent_replace(handle, 0, &extent);
1290 } else if ((logical == extent.e_lblk - 1) &&
1291 (physical == extent.e_pblk - 1) &&
1292 (new_uninit == extent_uninit) &&
1293 ((int) extent.e_len < max_len - 1)) {
1297 retval = ext2fs_extent_replace(handle, 0, &extent);
1298 } else if (has_next &&
1299 (logical == next_extent.e_lblk - 1) &&
1300 (physical == next_extent.e_pblk - 1) &&
1301 (new_uninit == next_uninit) &&
1302 ((int) next_extent.e_len < max_len - 1)) {
1303 retval = ext2fs_extent_get(handle,
1304 EXT2_EXTENT_NEXT_LEAF,
1308 next_extent.e_len++;
1309 next_extent.e_lblk--;
1310 next_extent.e_pblk--;
1311 retval = ext2fs_extent_replace(handle, 0, &next_extent);
1312 } else if (logical < extent.e_lblk)
1313 retval = ext2fs_extent_insert(handle, 0, &newextent);
1315 retval = ext2fs_extent_insert(handle,
1316 EXT2_EXTENT_INSERT_AFTER, &newextent);
1319 retval = ext2fs_extent_fix_parents(handle);
1322 } else if ((logical == extent.e_lblk) && (extent.e_len == 1)) {
1324 printf("(re/un)mapping only block in extent\n");
1327 retval = ext2fs_extent_replace(handle, 0, &newextent);
1329 retval = ext2fs_extent_delete(handle, 0);
1332 ec = ext2fs_extent_fix_parents(handle);
1333 if (ec != EXT2_ET_NO_CURRENT_NODE)
1339 } else if (logical == extent.e_lblk + extent.e_len - 1) {
1341 printf("(re/un)mapping last block in extent\n");
1345 (logical == (next_extent.e_lblk - 1)) &&
1346 (physical == (next_extent.e_pblk - 1)) &&
1347 (new_uninit == next_uninit) &&
1348 ((int) next_extent.e_len < max_len - 1)) {
1349 retval = ext2fs_extent_get(handle,
1350 EXT2_EXTENT_NEXT_LEAF, &next_extent);
1353 next_extent.e_len++;
1354 next_extent.e_lblk--;
1355 next_extent.e_pblk--;
1356 retval = ext2fs_extent_replace(handle, 0,
1360 retval = ext2fs_extent_fix_parents(handle);
1364 retval = ext2fs_extent_insert(handle,
1365 EXT2_EXTENT_INSERT_AFTER, &newextent);
1368 /* Now pointing at inserted extent; move back to prev */
1369 retval = ext2fs_extent_get(handle,
1370 EXT2_EXTENT_PREV_LEAF,
1376 retval = ext2fs_extent_replace(handle, 0, &extent);
1379 } else if (logical == extent.e_lblk) {
1381 printf("(re/un)mapping first block in extent\n");
1385 (logical == (prev_extent.e_lblk +
1386 prev_extent.e_len)) &&
1387 (physical == (prev_extent.e_pblk +
1388 prev_extent.e_len)) &&
1389 (new_uninit == prev_uninit) &&
1390 ((int) prev_extent.e_len < max_len-1)) {
1391 retval = ext2fs_extent_get(handle,
1392 EXT2_EXTENT_PREV_LEAF, &prev_extent);
1395 prev_extent.e_len++;
1396 retval = ext2fs_extent_replace(handle, 0,
1399 retval = ext2fs_extent_insert(handle,
1403 retval = ext2fs_extent_get(handle,
1404 EXT2_EXTENT_NEXT_LEAF,
1412 retval = ext2fs_extent_replace(handle, 0, &extent);
1415 retval = ext2fs_extent_fix_parents(handle);
1422 printf("(re/un)mapping in middle of extent\n");
1424 /* need to split this extent; later */
1426 orig_length = extent.e_len;
1428 /* shorten pre-split extent */
1429 extent.e_len = (logical - extent.e_lblk);
1430 retval = ext2fs_extent_replace(handle, 0, &extent);
1433 /* insert our new extent, if any */
1435 /* insert new extent after current */
1436 retval = ext2fs_extent_insert(handle,
1437 EXT2_EXTENT_INSERT_AFTER, &newextent);
1441 /* add post-split extent */
1442 extent.e_pblk += extent.e_len + 1;
1443 extent.e_lblk += extent.e_len + 1;
1444 extent.e_len = orig_length - extent.e_len - 1;
1445 retval = ext2fs_extent_insert(handle,
1446 EXT2_EXTENT_INSERT_AFTER, &extent);
1452 /* get handle back to its position */
1453 if (orig_height > handle->max_depth)
1454 orig_height = handle->max_depth; /* In case we shortened the tree */
1455 ext2fs_extent_goto2(handle, orig_height, orig_lblk);
1459 errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle, int flags)
1461 struct extent_path *path;
1463 struct ext3_extent_header *eh;
1464 errcode_t retval = 0;
1466 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1468 if (!(handle->fs->flags & EXT2_FLAG_RW))
1469 return EXT2_ET_RO_FILSYS;
1472 return EXT2_ET_NO_CURRENT_NODE;
1476 struct ext2fs_extent extent;
1478 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT,
1481 printf("extent delete %u ", handle->ino);
1482 dbg_print_extent(0, &extent);
1487 path = handle->path + handle->level;
1489 return EXT2_ET_NO_CURRENT_NODE;
1494 memmove(cp, cp + sizeof(struct ext3_extent_idx),
1495 path->left * sizeof(struct ext3_extent_idx));
1498 struct ext3_extent_idx *ix = path->curr;
1502 if (--path->entries == 0)
1505 /* if non-root node has no entries left, remove it & parent ptr to it */
1506 if (path->entries == 0 && handle->level) {
1507 if (!(flags & EXT2_EXTENT_DELETE_KEEP_EMPTY)) {
1508 struct ext2fs_extent extent;
1510 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP,
1515 retval = ext2fs_extent_delete(handle, flags);
1516 handle->inode->i_blocks -=
1517 (handle->fs->blocksize *
1518 EXT2FS_CLUSTER_RATIO(handle->fs)) / 512;
1519 retval = ext2fs_write_inode(handle->fs, handle->ino,
1521 ext2fs_block_alloc_stats2(handle->fs,
1525 eh = (struct ext3_extent_header *) path->buf;
1526 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
1527 if ((path->entries == 0) && (handle->level == 0))
1528 eh->eh_depth = handle->max_depth = 0;
1529 retval = update_path(handle);
1534 errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle,
1535 struct ext2_extent_info *info)
1537 struct extent_path *path;
1539 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1541 memset(info, 0, sizeof(struct ext2_extent_info));
1543 path = handle->path + handle->level;
1546 info->curr_entry = ((char *) path->curr - path->buf) /
1547 sizeof(struct ext3_extent_idx);
1549 info->curr_entry = 0;
1550 info->num_entries = path->entries;
1551 info->max_entries = path->max_entries;
1552 info->bytes_avail = (path->max_entries - path->entries) *
1553 sizeof(struct ext3_extent);
1556 info->curr_level = handle->level;
1557 info->max_depth = handle->max_depth;
1558 info->max_lblk = ((__u64) 1 << 32) - 1;
1559 info->max_pblk = ((__u64) 1 << 48) - 1;
1560 info->max_len = (1UL << 15);
1561 info->max_uninit_len = (1UL << 15) - 1;
1568 * Override debugfs's prompt
1570 const char *debug_prog_name = "tst_extents";