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 Public
24 #include <sys/types.h>
33 * Definitions to be dropped in lib/ext2fs/ext2fs.h
52 struct ext2_extent_handle {
56 struct ext2_inode *inode;
60 struct extent_path *path;
63 struct ext2_extent_path {
70 * Useful Debugging stuff
74 static void dbg_show_header(struct ext3_extent_header *eh)
76 printf("header: magic=%x entries=%u max=%u depth=%u generation=%u\n",
77 eh->eh_magic, eh->eh_entries, eh->eh_max, eh->eh_depth,
81 static void dbg_show_index(struct ext3_extent_idx *ix)
83 printf("index: block=%u leaf=%u leaf_hi=%u unused=%u\n",
84 ix->ei_block, ix->ei_leaf, ix->ei_leaf_hi, ix->ei_unused);
87 static void dbg_show_extent(struct ext3_extent *ex)
89 printf("extent: block=%u-%u len=%u start=%u start_hi=%u\n",
90 ex->ee_block, ex->ee_block + ex->ee_len - 1,
91 ex->ee_len, ex->ee_start, ex->ee_start_hi);
94 static void dbg_print_extent(char *desc, struct ext2fs_extent *extent)
98 printf("extent: lblk %llu--%llu, len %lu, pblk %llu, flags: ",
99 extent->e_lblk, extent->e_lblk + extent->e_len - 1,
100 extent->e_len, extent->e_pblk);
101 if (extent->e_flags & EXT2_EXTENT_FLAGS_LEAF)
102 fputs("LEAF ", stdout);
103 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT)
104 fputs("UNINIT ", stdout);
105 if (extent->e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)
106 fputs("2ND_VISIT ", stdout);
107 if (!extent->e_flags)
108 fputs("(none)", stdout);
113 #define dbg_printf(fmt, args...) printf(fmt, ## args)
115 #define dbg_show_header(eh) do { } while (0)
116 #define dbg_show_index(ix) do { } while (0)
117 #define dbg_show_extent(ex) do { } while (0)
118 #define dbg_print_extent(desc, ex) do { } while (0)
119 #define dbg_printf(fmt, args...) do { } while (0)
123 * Verify the extent header as being sane
125 errcode_t ext2fs_extent_header_verify(void *ptr, int size)
127 int eh_max, entry_size;
128 struct ext3_extent_header *eh = ptr;
131 if (ext2fs_le16_to_cpu(eh->eh_magic) != EXT3_EXT_MAGIC)
132 return EXT2_ET_EXTENT_HEADER_BAD;
133 if (ext2fs_le16_to_cpu(eh->eh_entries) > ext2fs_le16_to_cpu(eh->eh_max))
134 return EXT2_ET_EXTENT_HEADER_BAD;
135 if (eh->eh_depth == 0)
136 entry_size = sizeof(struct ext3_extent);
138 entry_size = sizeof(struct ext3_extent_idx);
140 eh_max = (size - sizeof(*eh)) / entry_size;
141 /* Allow two extent-sized items at the end of the block, for
142 * ext4_extent_tail with checksum in the future. */
143 if ((ext2fs_le16_to_cpu(eh->eh_max) > eh_max) ||
144 (ext2fs_le16_to_cpu(eh->eh_max) < (eh_max - 2)))
145 return EXT2_ET_EXTENT_HEADER_BAD;
152 * Begin functions to handle an inode's extent information
154 extern void ext2fs_extent_free(ext2_extent_handle_t handle)
162 ext2fs_free_mem(&handle->inode);
164 for (i=1; i < handle->max_depth; i++) {
165 if (handle->path[i].buf)
166 ext2fs_free_mem(&handle->path[i].buf);
168 ext2fs_free_mem(&handle->path);
170 ext2fs_free_mem(&handle);
173 extern errcode_t ext2fs_extent_open(ext2_filsys fs, ext2_ino_t ino,
174 ext2_extent_handle_t *ret_handle)
176 struct ext2_extent_handle *handle;
178 int isize = EXT2_INODE_SIZE(fs->super);
180 struct ext3_extent_header *eh;
182 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
184 if ((ino == 0) || (ino > fs->super->s_inodes_count))
185 return EXT2_ET_BAD_INODE_NUM;
187 retval = ext2fs_get_mem(sizeof(struct ext2_extent_handle), &handle);
190 memset(handle, 0, sizeof(struct ext2_extent_handle));
192 retval = ext2fs_get_mem(isize, &handle->inode);
199 retval = ext2fs_read_inode_full(fs, ino, handle->inode, isize);
203 eh = (struct ext3_extent_header *) &handle->inode->i_block[0];
205 for (i=0; i < EXT2_N_BLOCKS; i++)
206 if (handle->inode->i_block[i])
208 if (i >= EXT2_N_BLOCKS) {
209 eh->eh_magic = ext2fs_cpu_to_le16(EXT3_EXT_MAGIC);
212 i = (sizeof(handle->inode->i_block) - sizeof(*eh)) /
213 sizeof(struct ext3_extent);
214 eh->eh_max = ext2fs_cpu_to_le16(i);
215 handle->inode->i_flags |= EXT4_EXTENTS_FL;
218 if (!(handle->inode->i_flags & EXT4_EXTENTS_FL))
219 return EXT2_ET_INODE_NOT_EXTENT;
221 retval = ext2fs_extent_header_verify(eh, sizeof(handle->inode->i_block));
225 handle->max_depth = ext2fs_le16_to_cpu(eh->eh_depth);
226 handle->type = ext2fs_le16_to_cpu(eh->eh_magic);
228 retval = ext2fs_get_mem(((handle->max_depth+1) *
229 sizeof(struct extent_path)),
231 memset(handle->path, 0,
232 (handle->max_depth+1) * sizeof(struct extent_path));
233 handle->path[0].buf = (char *) handle->inode->i_block;
235 handle->path[0].left = handle->path[0].entries =
236 ext2fs_le16_to_cpu(eh->eh_entries);
237 handle->path[0].max_entries = ext2fs_le16_to_cpu(eh->eh_max);
238 handle->path[0].curr = 0;
239 handle->path[0].end_blk =
240 ((((__u64) handle->inode->i_size_high << 32) +
241 handle->inode->i_size + (fs->blocksize - 1))
242 >> EXT2_BLOCK_SIZE_BITS(fs->super));
243 handle->path[0].visit_num = 1;
245 handle->magic = EXT2_ET_MAGIC_EXTENT_HANDLE;
247 *ret_handle = handle;
251 ext2fs_extent_free(handle);
256 * This function is responsible for (optionally) moving through the
257 * extent tree and then returning the current extent
259 errcode_t ext2fs_extent_get(ext2_extent_handle_t handle,
260 int flags, struct ext2fs_extent *extent)
262 struct extent_path *path, *newpath;
263 struct ext3_extent_header *eh;
264 struct ext3_extent_idx *ix = 0;
265 struct ext3_extent *ex;
271 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
274 return EXT2_ET_NO_CURRENT_NODE;
276 orig_op = op = flags & EXT2_EXTENT_MOVE_MASK;
279 path = handle->path + handle->level;
280 if ((orig_op == EXT2_EXTENT_NEXT) ||
281 (orig_op == EXT2_EXTENT_NEXT_LEAF)) {
282 if (handle->level < handle->max_depth) {
284 if (path->visit_num == 0) {
286 op = EXT2_EXTENT_DOWN;
287 } else if (path->left > 0)
288 op = EXT2_EXTENT_NEXT_SIB;
289 else if (handle->level > 0)
292 return EXT2_ET_EXTENT_NO_NEXT;
296 op = EXT2_EXTENT_NEXT_SIB;
297 else if (handle->level > 0)
300 return EXT2_ET_EXTENT_NO_NEXT;
302 if (op != EXT2_EXTENT_NEXT_SIB) {
303 dbg_printf("<<<< OP = %s\n",
304 (op == EXT2_EXTENT_DOWN) ? "down" :
305 ((op == EXT2_EXTENT_UP) ? "up" : "unknown"));
309 if ((orig_op == EXT2_EXTENT_PREV) ||
310 (orig_op == EXT2_EXTENT_PREV_LEAF)) {
311 if (handle->level < handle->max_depth) {
313 if (path->visit_num > 0 ) {
314 /* path->visit_num = 0; */
315 op = EXT2_EXTENT_DOWN_AND_LAST;
316 } else if (path->left < path->entries-1)
317 op = EXT2_EXTENT_PREV_SIB;
318 else if (handle->level > 0)
321 return EXT2_ET_EXTENT_NO_PREV;
324 if (path->left < path->entries-1)
325 op = EXT2_EXTENT_PREV_SIB;
326 else if (handle->level > 0)
329 return EXT2_ET_EXTENT_NO_PREV;
331 if (op != EXT2_EXTENT_PREV_SIB) {
332 dbg_printf("<<<< OP = %s\n",
333 (op == EXT2_EXTENT_DOWN_AND_LAST) ? "down/last" :
334 ((op == EXT2_EXTENT_UP) ? "up" : "unknown"));
338 if (orig_op == EXT2_EXTENT_LAST_LEAF) {
339 if ((handle->level < handle->max_depth) &&
341 op = EXT2_EXTENT_DOWN;
343 op = EXT2_EXTENT_LAST_SIB;
344 dbg_printf("<<<< OP = %s\n",
345 (op == EXT2_EXTENT_DOWN) ? "down" : "last_sib");
349 case EXT2_EXTENT_CURRENT:
352 case EXT2_EXTENT_ROOT:
354 path = handle->path + handle->level;
355 case EXT2_EXTENT_FIRST_SIB:
356 path->left = path->entries;
358 case EXT2_EXTENT_NEXT_SIB:
360 return EXT2_ET_EXTENT_NO_NEXT;
365 eh = (struct ext3_extent_header *) path->buf;
366 ix = EXT_FIRST_INDEX(eh);
372 case EXT2_EXTENT_PREV_SIB:
374 path->left+1 >= path->entries)
375 return EXT2_ET_EXTENT_NO_PREV;
380 if (handle->level < handle->max_depth)
383 case EXT2_EXTENT_LAST_SIB:
384 eh = (struct ext3_extent_header *) path->buf;
385 path->curr = EXT_LAST_EXTENT(eh);
391 if (handle->level <= 0)
392 return EXT2_ET_EXTENT_NO_UP;
396 if ((orig_op == EXT2_EXTENT_PREV) ||
397 (orig_op == EXT2_EXTENT_PREV_LEAF))
400 case EXT2_EXTENT_DOWN:
401 case EXT2_EXTENT_DOWN_AND_LAST:
402 if (!path->curr ||(handle->level >= handle->max_depth))
403 return EXT2_ET_EXTENT_NO_DOWN;
408 retval = ext2fs_get_mem(handle->fs->blocksize,
413 blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
414 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
415 if ((handle->fs->flags & EXT2_FLAG_IMAGE_FILE) &&
416 (handle->fs->io != handle->fs->image_io))
417 memset(newpath->buf, 0, handle->fs->blocksize);
419 retval = io_channel_read_blk(handle->fs->io,
420 blk, 1, newpath->buf);
426 eh = (struct ext3_extent_header *) newpath->buf;
428 retval = ext2fs_extent_header_verify(eh, handle->fs->blocksize);
432 newpath->left = newpath->entries =
433 ext2fs_le16_to_cpu(eh->eh_entries);
434 newpath->max_entries = ext2fs_le16_to_cpu(eh->eh_max);
436 if (path->left > 0) {
438 newpath->end_blk = ext2fs_le32_to_cpu(ix->ei_block);
440 newpath->end_blk = path->end_blk;
443 if (op == EXT2_EXTENT_DOWN) {
444 ix = EXT_FIRST_INDEX((struct ext3_extent_header *) eh);
446 path->left = path->entries - 1;
449 ix = EXT_LAST_INDEX((struct ext3_extent_header *) eh);
452 if (handle->level < handle->max_depth)
456 dbg_printf("Down to level %d/%d, end_blk=%llu\n",
457 handle->level, handle->max_depth,
462 return EXT2_ET_OP_NOT_SUPPORTED;
466 return EXT2_ET_NO_CURRENT_NODE;
469 dbg_printf("(Left %d)\n", path->left);
471 if (handle->level == handle->max_depth) {
472 ex = (struct ext3_extent *) ix;
474 extent->e_pblk = ext2fs_le32_to_cpu(ex->ee_start) +
475 ((__u64) ext2fs_le16_to_cpu(ex->ee_start_hi) << 32);
476 extent->e_lblk = ext2fs_le32_to_cpu(ex->ee_block);
477 extent->e_len = ext2fs_le16_to_cpu(ex->ee_len);
478 extent->e_flags |= EXT2_EXTENT_FLAGS_LEAF;
479 if (extent->e_len > EXT_INIT_MAX_LEN) {
480 extent->e_len -= EXT_INIT_MAX_LEN;
481 extent->e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
484 extent->e_pblk = ext2fs_le32_to_cpu(ix->ei_leaf) +
485 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
486 extent->e_lblk = ext2fs_le32_to_cpu(ix->ei_block);
487 if (path->left > 0) {
489 end_blk = ext2fs_le32_to_cpu(ix->ei_block);
491 end_blk = path->end_blk;
493 extent->e_len = end_blk - extent->e_lblk;
496 extent->e_flags |= EXT2_EXTENT_FLAGS_SECOND_VISIT;
498 if (((orig_op == EXT2_EXTENT_NEXT_LEAF) ||
499 (orig_op == EXT2_EXTENT_PREV_LEAF)) &&
500 (handle->level != handle->max_depth))
503 if ((orig_op == EXT2_EXTENT_LAST_LEAF) &&
504 ((handle->level != handle->max_depth) ||
511 static errcode_t update_path(ext2_extent_handle_t handle)
515 struct ext3_extent_idx *ix;
517 if (handle->level == 0) {
518 retval = ext2fs_write_inode_full(handle->fs, handle->ino,
519 handle->inode, EXT2_INODE_SIZE(handle->fs->super));
521 ix = handle->path[handle->level - 1].curr;
522 blk = ext2fs_le32_to_cpu(ix->ei_leaf) +
523 ((__u64) ext2fs_le16_to_cpu(ix->ei_leaf_hi) << 32);
525 retval = io_channel_write_blk(handle->fs->io,
526 blk, 1, handle->path[handle->level].buf);
532 errcode_t ext2fs_extent_save_path(ext2_extent_handle_t handle,
533 ext2_extent_path_t *ret_path)
535 ext2_extent_path_t save_path;
536 struct ext2fs_extent extent;
537 struct ext2_extent_info info;
540 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
544 retval = ext2fs_extent_get_info(handle, &info);
548 retval = ext2fs_get_mem(sizeof(struct ext2_extent_path), &save_path);
551 memset(save_path, 0, sizeof(struct ext2_extent_path));
553 save_path->magic = EXT2_ET_MAGIC_EXTENT_PATH;
554 save_path->leaf_height = info.max_depth - info.curr_level - 1;
555 save_path->lblk = extent.e_lblk;
557 *ret_path = save_path;
561 errcode_t ext2fs_extent_free_path(ext2_extent_path_t path)
563 EXT2_CHECK_MAGIC(path, EXT2_ET_MAGIC_EXTENT_PATH);
565 ext2fs_free_mem(&path);
571 * Go to the node at leaf_level which contains logical block blk.
573 * leaf_level is height from the leaf node level, i.e.
574 * leaf_level 0 is at leaf node, leaf_level 1 is 1 above etc.
576 * If "blk" has no mapping (hole) then handle is left at last
579 static errcode_t extent_goto(ext2_extent_handle_t handle,
580 int leaf_level, blk64_t blk)
582 struct ext2fs_extent extent;
585 retval = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent);
589 if (leaf_level > handle->max_depth) {
590 dbg_printf("leaf level %d greater than tree depth %d\n",
591 leaf_level, handle->max_depth);
592 return EXT2_ET_OP_NOT_SUPPORTED;
595 dbg_print_extent("root", &extent);
597 if (handle->max_depth - handle->level == leaf_level) {
598 /* block is in this &extent */
599 if ((blk >= extent.e_lblk) &&
600 (blk < extent.e_lblk + extent.e_len))
602 if (blk < extent.e_lblk) {
603 retval = ext2fs_extent_get(handle,
604 EXT2_EXTENT_PREV_SIB,
606 return EXT2_ET_EXTENT_NOT_FOUND;
608 retval = ext2fs_extent_get(handle,
609 EXT2_EXTENT_NEXT_SIB,
611 if (retval == EXT2_ET_EXTENT_NO_NEXT)
612 return EXT2_ET_EXTENT_NOT_FOUND;
618 retval = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT_SIB,
620 if (retval == EXT2_ET_EXTENT_NO_NEXT)
625 dbg_print_extent("next", &extent);
626 if (blk == extent.e_lblk)
628 if (blk > extent.e_lblk)
631 retval = ext2fs_extent_get(handle, EXT2_EXTENT_PREV_SIB,
636 dbg_print_extent("prev", &extent);
639 retval = ext2fs_extent_get(handle, EXT2_EXTENT_DOWN,
644 dbg_print_extent("down", &extent);
648 errcode_t ext2fs_extent_goto(ext2_extent_handle_t handle,
651 return extent_goto(handle, 0, blk);
655 * Traverse back up to root fixing parents of current node as needed.
657 * If we changed start of first entry in a node, fix parent index start
660 * Safe to call for any position in node; if not at the first entry,
661 * will simply return.
663 static errcode_t ext2fs_extent_fix_parents(ext2_extent_handle_t handle)
667 struct extent_path *path;
668 struct ext2fs_extent extent;
670 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
672 if (!(handle->fs->flags & EXT2_FLAG_RW))
673 return EXT2_ET_RO_FILSYS;
676 return EXT2_ET_NO_CURRENT_NODE;
678 path = handle->path + handle->level;
680 return EXT2_ET_NO_CURRENT_NODE;
682 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
686 /* modified node's start block */
687 start = extent.e_lblk;
689 /* traverse up until index not first, or startblk matches, or top */
690 while (handle->level > 0 &&
691 (path->left == path->entries - 1)) {
692 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
695 if (extent.e_lblk == start)
697 path = handle->path + handle->level;
698 extent.e_len += (extent.e_lblk - start);
699 extent.e_lblk = start;
700 retval = ext2fs_extent_replace(handle, 0, &extent);
706 /* put handle back to where we started */
707 retval = ext2fs_extent_goto(handle, start);
712 errcode_t ext2fs_extent_replace(ext2_extent_handle_t handle,
713 int flags EXT2FS_ATTR((unused)),
714 struct ext2fs_extent *extent)
716 struct extent_path *path;
717 struct ext3_extent_idx *ix;
718 struct ext3_extent *ex;
720 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
722 if (!(handle->fs->flags & EXT2_FLAG_RW))
723 return EXT2_ET_RO_FILSYS;
726 return EXT2_ET_NO_CURRENT_NODE;
728 path = handle->path + handle->level;
730 return EXT2_ET_NO_CURRENT_NODE;
732 if (handle->level == handle->max_depth) {
735 ex->ee_block = ext2fs_cpu_to_le32(extent->e_lblk);
736 ex->ee_start = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
737 ex->ee_start_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
738 if (extent->e_flags & EXT2_EXTENT_FLAGS_UNINIT) {
739 if (extent->e_len > EXT_UNINIT_MAX_LEN)
740 return EXT2_ET_EXTENT_INVALID_LENGTH;
741 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len +
744 if (extent->e_len > EXT_INIT_MAX_LEN)
745 return EXT2_ET_EXTENT_INVALID_LENGTH;
746 ex->ee_len = ext2fs_cpu_to_le16(extent->e_len);
751 ix->ei_leaf = ext2fs_cpu_to_le32(extent->e_pblk & 0xFFFFFFFF);
752 ix->ei_leaf_hi = ext2fs_cpu_to_le16(extent->e_pblk >> 32);
753 ix->ei_block = ext2fs_cpu_to_le32(extent->e_lblk);
761 * allocate a new block, move half the current node to it, and update parent
763 * handle will be left pointing at original record.
765 static errcode_t extent_node_split(ext2_extent_handle_t handle, int flags)
767 errcode_t retval = 0;
769 blk64_t new_node_start;
771 blk64_t goal_blk = 0;
773 char *block_buf = NULL;
774 struct ext2fs_extent extent;
775 struct extent_path *path, *newpath = 0;
776 struct ext3_extent *ex;
777 struct ext3_extent_header *eh, *neweh;
781 struct ext2_extent_info info;
784 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
786 if (!(handle->fs->flags & EXT2_FLAG_RW))
787 return EXT2_ET_RO_FILSYS;
790 return EXT2_ET_NO_CURRENT_NODE;
792 dbg_printf("splitting node at level %d\n", handle->level);
794 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
798 retval = ext2fs_extent_get_info(handle, &info);
802 /* save the position we were originally splitting... */
803 orig_height = info.max_depth - info.curr_level;
804 orig_lblk = extent.e_lblk;
806 /* Is there room in the parent for a new entry? */
808 (handle->path[handle->level - 1].entries >=
809 handle->path[handle->level - 1].max_entries)) {
811 dbg_printf("parent level %d full; splitting it too\n",
813 /* split the parent */
814 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
817 goal_blk = extent.e_pblk;
819 retval = extent_node_split(handle, 0);
823 /* get handle back to our original split position */
824 retval = extent_goto(handle, orig_height, orig_lblk);
829 /* At this point, parent should have room for this split */
830 path = handle->path + handle->level;
832 return EXT2_ET_NO_CURRENT_NODE;
834 /* extent header of the current node we'll split */
835 eh = (struct ext3_extent_header *)path->buf;
837 /* splitting root level means moving them all out */
838 if (handle->level == 0) {
840 tocopy = ext2fs_le16_to_cpu(eh->eh_entries);
841 retval = ext2fs_get_mem(((handle->max_depth+2) *
842 sizeof(struct extent_path)),
847 ((handle->max_depth+2) * sizeof(struct extent_path)));
849 tocopy = ext2fs_le16_to_cpu(eh->eh_entries) / 2;
852 dbg_printf("will copy out %d of %d entries at level %d\n",
853 tocopy, ext2fs_le16_to_cpu(eh->eh_entries),
857 dbg_printf("Nothing to copy to new block!\n");
858 retval = EXT2_ET_CANT_SPLIT_EXTENT;
862 /* first we need a new block, or can do nothing. */
863 block_buf = malloc(handle->fs->blocksize);
870 dgrp_t group = ext2fs_group_of_ino(handle->fs, handle->ino);
871 __u8 log_flex = handle->fs->super->s_log_groups_per_flex;
874 group = group & ~((1 << (log_flex)) - 1);
875 goal_blk = (group * handle->fs->super->s_blocks_per_group) +
876 handle->fs->super->s_first_data_block;
878 retval = ext2fs_alloc_block(handle->fs, (blk_t) goal_blk, block_buf,
883 dbg_printf("will copy to new node at block %lu\n", new_node_pblk);
885 /* Copy data into new block buffer */
886 /* First the header for the new block... */
887 neweh = (struct ext3_extent_header *) block_buf;
888 memcpy(neweh, eh, sizeof(struct ext3_extent_header));
889 neweh->eh_entries = ext2fs_cpu_to_le16(tocopy);
890 neweh->eh_max = ext2fs_cpu_to_le16((handle->fs->blocksize -
891 sizeof(struct ext3_extent_header)) /
892 sizeof(struct ext3_extent));
894 /* then the entries for the new block... */
895 memcpy(EXT_FIRST_INDEX(neweh),
896 EXT_FIRST_INDEX(eh) +
897 (ext2fs_le16_to_cpu(eh->eh_entries) - tocopy),
898 sizeof(struct ext3_extent_idx) * tocopy);
900 new_node_start = ext2fs_le32_to_cpu(EXT_FIRST_INDEX(neweh)->ei_block);
902 /* ...and write the new node block out to disk. */
903 retval = io_channel_write_blk(handle->fs->io, new_node_pblk, 1, block_buf);
908 /* OK! we've created the new node; now adjust the tree */
910 /* current path now has fewer active entries, we copied some out */
911 if (handle->level == 0) {
912 memcpy(newpath, path,
913 sizeof(struct extent_path) * (handle->max_depth+1));
914 handle->path = newpath;
918 path->left = path->max_entries - 1;
920 eh->eh_depth = ext2fs_cpu_to_le16(handle->max_depth);
922 path->entries -= tocopy;
923 path->left -= tocopy;
926 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
927 /* this writes out the node, incl. the modified header */
928 retval = update_path(handle);
932 /* now go up and insert/replace index for new node we created */
934 retval = ext2fs_extent_get(handle, EXT2_EXTENT_FIRST_SIB, &extent);
938 extent.e_lblk = new_node_start;
939 extent.e_pblk = new_node_pblk;
940 extent.e_len = handle->path[0].end_blk - extent.e_lblk;
941 retval = ext2fs_extent_replace(handle, 0, &extent);
945 __u32 new_node_length;
947 retval = ext2fs_extent_get(handle, EXT2_EXTENT_UP, &extent);
948 /* will insert after this one; it's length is shorter now */
949 new_node_length = new_node_start - extent.e_lblk;
950 extent.e_len -= new_node_length;
951 retval = ext2fs_extent_replace(handle, 0, &extent);
955 /* now set up the new extent and insert it */
956 extent.e_lblk = new_node_start;
957 extent.e_pblk = new_node_pblk;
958 extent.e_len = new_node_length;
959 retval = ext2fs_extent_insert(handle, EXT2_EXTENT_INSERT_AFTER, &extent);
964 /* get handle back to our original position */
965 retval = extent_goto(handle, orig_height, orig_lblk);
969 /* new node hooked in, so update inode block count (do this here?) */
970 handle->inode->i_blocks += handle->fs->blocksize / 512;
971 retval = ext2fs_write_inode_full(handle->fs, handle->ino,
972 handle->inode, EXT2_INODE_SIZE(handle->fs->super));
978 ext2fs_free_mem(&newpath);
985 errcode_t ext2fs_extent_insert(ext2_extent_handle_t handle, int flags,
986 struct ext2fs_extent *extent)
988 struct extent_path *path;
989 struct ext3_extent_idx *ix;
990 struct ext3_extent_header *eh;
993 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
995 if (!(handle->fs->flags & EXT2_FLAG_RW))
996 return EXT2_ET_RO_FILSYS;
999 return EXT2_ET_NO_CURRENT_NODE;
1001 path = handle->path + handle->level;
1003 if (path->entries >= path->max_entries) {
1004 if (flags & EXT2_EXTENT_INSERT_NOSPLIT) {
1005 return EXT2_ET_CANT_INSERT_EXTENT;
1007 dbg_printf("node full - splitting\n");
1008 retval = extent_node_split(handle, 0);
1011 path = handle->path + handle->level;
1015 eh = (struct ext3_extent_header *) path->buf;
1018 if (flags & EXT2_EXTENT_INSERT_AFTER) {
1023 ix = EXT_FIRST_INDEX(eh);
1027 if (path->left >= 0)
1029 (path->left+1) * sizeof(struct ext3_extent_idx));
1033 eh = (struct ext3_extent_header *) path->buf;
1034 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
1036 retval = ext2fs_extent_replace(handle, 0, extent);
1040 retval = update_path(handle);
1047 ext2fs_extent_delete(handle, 0);
1052 * Sets the physical block for a logical file block in the extent tree.
1054 * May: map unmapped, unmap mapped, or remap mapped blocks.
1056 * Mapping an unmapped block adds a single-block extent.
1058 * Unmapping first or last block modifies extent in-place
1059 * - But may need to fix parent's starts too in first-block case
1061 * Mapping any unmapped block requires adding a (single-block) extent
1062 * and inserting into proper point in tree.
1064 * Modifying (unmapping or remapping) a block in the middle
1065 * of an extent requires splitting the extent.
1066 * - Remapping case requires new single-block extent.
1068 * Remapping first or last block adds an extent.
1070 * We really need extent adding to be smart about merging.
1073 errcode_t ext2fs_extent_set_bmap(ext2_extent_handle_t handle,
1074 blk64_t logical, blk64_t physical, int flags)
1076 errcode_t ec, retval = 0;
1077 int mapped = 1; /* logical is mapped? */
1079 int extent_uninit = 0;
1081 int max_len = EXT_INIT_MAX_LEN;
1083 struct extent_path *path;
1084 struct ext2fs_extent extent;
1085 struct ext2fs_extent newextent;
1086 struct ext2_extent_info info;
1088 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1090 if (!(handle->fs->flags & EXT2_FLAG_RW))
1091 return EXT2_ET_RO_FILSYS;
1094 return EXT2_ET_NO_CURRENT_NODE;
1096 path = handle->path + handle->level;
1098 if (flags & EXT2_EXTENT_SET_BMAP_UNINIT) {
1100 max_len = EXT_UNINIT_MAX_LEN;
1103 /* if (re)mapping, set up new extent to insert */
1105 newextent.e_len = 1;
1106 newextent.e_pblk = physical;
1107 newextent.e_lblk = logical;
1108 newextent.e_flags = EXT2_EXTENT_FLAGS_LEAF;
1110 newextent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
1113 /* special case if the extent tree is completely empty */
1114 if ((handle->max_depth == 0) && (path->entries == 0)) {
1115 retval = ext2fs_extent_insert(handle, 0, &newextent);
1119 /* save our original location in the extent tree */
1120 if ((retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT,
1122 if (retval != EXT2_ET_NO_CURRENT_NODE)
1124 memset(&extent, 0, sizeof(extent));
1126 if ((retval = ext2fs_extent_get_info(handle, &info)))
1128 orig_height = info.max_depth - info.curr_level;
1129 orig_lblk = extent.e_lblk;
1131 /* go to the logical spot we want to (re/un)map */
1132 retval = ext2fs_extent_goto(handle, logical);
1134 if (retval == EXT2_ET_EXTENT_NOT_FOUND) {
1138 dbg_printf("block already unmapped\n");
1146 * This may be the extent *before* the requested logical,
1147 * if it's currently unmapped.
1149 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
1152 if (extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
1155 /* check if already pointing to the requested physical */
1156 if (mapped && (new_uninit == extent_uninit) &&
1157 (extent.e_pblk + (logical - extent.e_lblk) == physical)) {
1158 dbg_printf("physical block unchanged\n");
1163 dbg_printf("mapping unmapped logical block\n");
1164 if ((logical == extent.e_lblk + extent.e_len) &&
1165 (physical == extent.e_pblk + extent.e_len) &&
1166 (new_uninit == extent_uninit) &&
1167 (extent.e_len < max_len-1)) {
1169 retval = ext2fs_extent_replace(handle, 0, &extent);
1171 retval = ext2fs_extent_insert(handle,
1172 EXT2_EXTENT_INSERT_AFTER, &newextent);
1175 retval = ext2fs_extent_fix_parents(handle);
1178 } else if ((logical == extent.e_lblk) && (extent.e_len == 1)) {
1179 dbg_printf("(re/un)mapping only block in extent\n");
1181 extent.e_pblk = physical;
1182 retval = ext2fs_extent_replace(handle, 0, &extent);
1184 retval = ext2fs_extent_delete(handle, 0);
1187 ec = ext2fs_extent_fix_parents(handle);
1188 if (ec != EXT2_ET_NO_CURRENT_NODE)
1194 } else if (logical == extent.e_lblk + extent.e_len - 1) {
1195 dbg_printf("(re/un)mapping last block in extent\n");
1197 retval = ext2fs_extent_replace(handle, 0, &extent);
1201 retval = ext2fs_extent_insert(handle,
1202 EXT2_EXTENT_INSERT_AFTER, &newextent);
1206 } else if (logical == extent.e_lblk) {
1207 dbg_printf("(re/un)mapping first block in extent\n");
1211 retval = ext2fs_extent_replace(handle, 0, &extent);
1215 /* insert new extent ahead of current */
1216 retval = ext2fs_extent_insert(handle,
1221 retval = ext2fs_extent_fix_parents(handle);
1228 dbg_printf("(re/un)mapping in middle of extent\n");
1229 /* need to split this extent; later */
1231 orig_length = extent.e_len;
1233 /* shorten pre-split extent */
1234 extent.e_len = (logical - extent.e_lblk);
1235 retval = ext2fs_extent_replace(handle, 0, &extent);
1238 /* insert our new extent, if any */
1240 /* insert new extent after current */
1241 retval = ext2fs_extent_insert(handle,
1242 EXT2_EXTENT_INSERT_AFTER, &newextent);
1246 /* add post-split extent */
1247 extent.e_pblk += extent.e_len + 1;
1248 extent.e_lblk += extent.e_len + 1;
1249 extent.e_len = orig_length - extent.e_len - 1;
1250 retval = ext2fs_extent_insert(handle,
1251 EXT2_EXTENT_INSERT_AFTER, &extent);
1257 /* get handle back to its position */
1258 if (orig_height > handle->max_depth)
1259 orig_height = handle->max_depth; /* In case we shortened the tree */
1260 extent_goto(handle, orig_height, orig_lblk);
1264 errcode_t ext2fs_extent_delete(ext2_extent_handle_t handle,
1265 int flags EXT2FS_ATTR((unused)))
1267 struct extent_path *path;
1269 struct ext3_extent_header *eh;
1272 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1274 if (!(handle->fs->flags & EXT2_FLAG_RW))
1275 return EXT2_ET_RO_FILSYS;
1278 return EXT2_ET_NO_CURRENT_NODE;
1280 path = handle->path + handle->level;
1282 return EXT2_ET_NO_CURRENT_NODE;
1287 memmove(cp, cp + sizeof(struct ext3_extent_idx),
1288 path->left * sizeof(struct ext3_extent_idx));
1291 struct ext3_extent_idx *ix = path->curr;
1296 if (path->entries == 0)
1299 eh = (struct ext3_extent_header *) path->buf;
1300 eh->eh_entries = ext2fs_cpu_to_le16(path->entries);
1302 retval = update_path(handle);
1307 errcode_t ext2fs_extent_get_info(ext2_extent_handle_t handle,
1308 struct ext2_extent_info *info)
1310 struct extent_path *path;
1312 EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EXTENT_HANDLE);
1314 memset(info, 0, sizeof(struct ext2_extent_info));
1316 path = handle->path + handle->level;
1319 info->curr_entry = ((char *) path->curr - path->buf) /
1320 sizeof(struct ext3_extent_idx);
1322 info->curr_entry = 0;
1323 info->num_entries = path->entries;
1324 info->max_entries = path->max_entries;
1325 info->bytes_avail = (path->max_entries - path->entries) *
1326 sizeof(struct ext3_extent);
1329 info->curr_level = handle->level;
1330 info->max_depth = handle->max_depth;
1331 info->max_lblk = ((__u64) 1 << 32) - 1;
1332 info->max_pblk = ((__u64) 1 << 48) - 1;
1333 info->max_len = (1UL << 15);
1334 info->max_uninit_len = (1UL << 15) - 1;
1341 #include "debugfs.h"
1344 * Hook in new commands into debugfs
1346 const char *debug_prog_name = "tst_extents";
1347 extern ss_request_table extent_cmds;
1348 ss_request_table *extra_cmds = &extent_cmds;
1350 ext2_ino_t current_ino = 0;
1351 ext2_extent_handle_t current_handle;
1353 int common_extent_args_process(int argc, char *argv[], int min_argc,
1354 int max_argc, const char *cmd,
1355 const char *usage, int flags)
1357 if (common_args_process(argc, argv, min_argc, max_argc, cmd,
1361 if (!current_handle) {
1362 com_err(cmd, 0, "Extent handle not open");
1368 void do_inode(int argc, char *argv[])
1372 struct ext3_extent_header *eh;
1375 if (check_fs_open(argv[0]))
1380 printf("Current inode is %d\n", current_ino);
1382 printf("No current inode\n");
1386 if (common_inode_args_process(argc, argv, &inode, 0)) {
1392 retval = ext2fs_extent_open(current_fs, inode, ¤t_handle);
1394 com_err(argv[1], retval, "while opening extent handle");
1398 current_ino = inode;
1400 printf("Loaded inode %d\n", current_ino);
1405 void generic_goto_node(char *cmd_name, int op)
1407 struct ext2fs_extent extent;
1410 if (check_fs_open(cmd_name))
1413 if (!current_handle) {
1414 com_err(cmd_name, 0, "Extent handle not open");
1418 retval = ext2fs_extent_get(current_handle, op, &extent);
1420 com_err(cmd_name, retval, 0);
1423 dbg_print_extent(0, &extent);
1426 void do_current_node(int argc, char *argv[])
1428 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT);
1431 void do_root_node(int argc, char *argv[])
1433 generic_goto_node(argv[0], EXT2_EXTENT_ROOT);
1436 void do_last_leaf(int argc, char *argv[])
1438 generic_goto_node(argv[0], EXT2_EXTENT_LAST_LEAF);
1441 void do_first_sib(int argc, char *argv[])
1443 generic_goto_node(argv[0], EXT2_EXTENT_FIRST_SIB);
1446 void do_last_sib(int argc, char *argv[])
1448 generic_goto_node(argv[0], EXT2_EXTENT_LAST_SIB);
1451 void do_next_sib(int argc, char *argv[])
1453 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_SIB);
1456 void do_prev_sib(int argc, char *argv[])
1458 generic_goto_node(argv[0], EXT2_EXTENT_PREV_SIB);
1461 void do_next_leaf(int argc, char *argv[])
1463 generic_goto_node(argv[0], EXT2_EXTENT_NEXT_LEAF);
1466 void do_prev_leaf(int argc, char *argv[])
1468 generic_goto_node(argv[0], EXT2_EXTENT_PREV_LEAF);
1471 void do_next(int argc, char *argv[])
1473 generic_goto_node(argv[0], EXT2_EXTENT_NEXT);
1476 void do_prev(int argc, char *argv[])
1478 generic_goto_node(argv[0], EXT2_EXTENT_PREV);
1481 void do_up(int argc, char *argv[])
1483 generic_goto_node(argv[0], EXT2_EXTENT_UP);
1486 void do_down(int argc, char *argv[])
1488 generic_goto_node(argv[0], EXT2_EXTENT_DOWN);
1491 void do_delete_node(int argc, char *argv[])
1496 if (common_extent_args_process(argc, argv, 1, 1, "delete_node",
1497 "", CHECK_FS_RW | CHECK_FS_BITMAPS))
1500 retval = ext2fs_extent_delete(current_handle, 0);
1502 com_err(argv[0], retval, 0);
1505 if (current_handle->path && current_handle->path[0].curr)
1506 do_current_node(argc, argv);
1509 void do_replace_node(int argc, char *argv[])
1511 const char *usage = "[--uninit] <lblk> <len> <pblk>";
1513 struct ext2fs_extent extent;
1516 if (common_extent_args_process(argc, argv, 3, 5, "replace_node",
1517 usage, CHECK_FS_RW | CHECK_FS_BITMAPS))
1522 if (!strcmp(argv[1], "--uninit")) {
1525 extent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
1529 fprintf(stderr, "Usage: %s %s\n", argv[0], usage);
1533 extent.e_lblk = parse_ulong(argv[1], argv[0], "logical block", &err);
1537 extent.e_len = parse_ulong(argv[2], argv[0], "logical block", &err);
1541 extent.e_pblk = parse_ulong(argv[3], argv[0], "logical block", &err);
1545 retval = ext2fs_extent_replace(current_handle, 0, &extent);
1547 com_err(argv[0], retval, 0);
1550 do_current_node(argc, argv);
1553 void do_split_node(int argc, char *argv[])
1556 struct ext2fs_extent extent;
1560 if (common_extent_args_process(argc, argv, 1, 1, "split_node",
1561 "", CHECK_FS_RW | CHECK_FS_BITMAPS))
1564 retval = extent_node_split(current_handle, flags);
1566 com_err(argv[0], retval, 0);
1569 do_current_node(argc, argv);
1572 void do_insert_node(int argc, char *argv[])
1574 const char *usage = "[--after] [--uninit] <lblk> <len> <pblk>";
1576 struct ext2fs_extent extent;
1581 if (common_extent_args_process(argc, argv, 3, 6, "insert_node",
1582 usage, CHECK_FS_RW | CHECK_FS_BITMAPS))
1590 if (!strcmp(argv[1], "--after")) {
1593 flags |= EXT2_EXTENT_INSERT_AFTER;
1596 if (!strcmp(argv[1], "--uninit")) {
1599 extent.e_flags |= EXT2_EXTENT_FLAGS_UNINIT;
1606 fprintf(stderr, "usage: %s %s\n", cmd, usage);
1610 extent.e_lblk = parse_ulong(argv[1], cmd,
1611 "logical block", &err);
1615 extent.e_len = parse_ulong(argv[2], cmd,
1620 extent.e_pblk = parse_ulong(argv[3], cmd,
1621 "pysical block", &err);
1625 retval = ext2fs_extent_insert(current_handle, flags, &extent);
1627 com_err(cmd, retval, 0);
1630 do_current_node(argc, argv);
1633 void do_set_bmap(int argc, char **argv)
1635 const char *usage = "[--uninit] <lblk> <pblk>";
1639 char *cmd = argv[0];
1643 if (common_extent_args_process(argc, argv, 3, 5, "set_bmap",
1644 usage, CHECK_FS_RW | CHECK_FS_BITMAPS))
1647 if (argc > 2 && !strcmp(argv[1], "--uninit")) {
1650 flags |= EXT2_EXTENT_SET_BMAP_UNINIT;
1654 fprintf(stderr, "Usage: %s %s\n", cmd, usage);
1658 logical = parse_ulong(argv[1], cmd,
1659 "logical block", &err);
1663 physical = parse_ulong(argv[2], cmd,
1664 "physical block", &err);
1668 retval = ext2fs_extent_set_bmap(current_handle, logical,
1669 (blk64_t) physical, flags);
1671 com_err(cmd, retval, 0);
1674 if (current_handle->path && current_handle->path[0].curr)
1675 do_current_node(argc, argv);
1678 void do_print_all(int argc, char **argv)
1680 const char *usage = "[--leaf-only|--reverse|--reverse-leaf]";
1681 struct ext2fs_extent extent;
1683 errcode_t end_err = EXT2_ET_EXTENT_NO_NEXT;
1684 int op = EXT2_EXTENT_NEXT;
1685 int first_op = EXT2_EXTENT_ROOT;
1688 if (common_extent_args_process(argc, argv, 1, 2, "print_all",
1693 if (!strcmp(argv[1], "--leaf-only"))
1694 op = EXT2_EXTENT_NEXT_LEAF;
1695 else if (!strcmp(argv[1], "--reverse")) {
1696 op = EXT2_EXTENT_PREV;
1697 first_op = EXT2_EXTENT_LAST_LEAF;
1698 end_err = EXT2_ET_EXTENT_NO_PREV;
1699 } else if (!strcmp(argv[1], "--reverse-leaf")) {
1700 op = EXT2_EXTENT_PREV_LEAF;
1701 first_op = EXT2_EXTENT_LAST_LEAF;
1702 end_err = EXT2_ET_EXTENT_NO_PREV;
1704 fprintf(stderr, "Usage: %s %s\n", argv[0], usage);
1709 retval = ext2fs_extent_get(current_handle, first_op, &extent);
1711 com_err(argv[0], retval, 0);
1714 dbg_print_extent(0, &extent);
1717 retval = ext2fs_extent_get(current_handle, op, &extent);
1718 if (retval == end_err)
1722 com_err(argv[0], retval, 0);
1725 dbg_print_extent(0, &extent);
1729 void do_info(int argc, char **argv)
1731 struct ext2fs_extent extent;
1732 struct ext2_extent_info info;
1735 if (common_extent_args_process(argc, argv, 1, 1, "info", "", 0))
1738 retval = ext2fs_extent_get_info(current_handle, &info);
1740 com_err(argv[0], retval, 0);
1744 retval = ext2fs_extent_get(current_handle,
1745 EXT2_EXTENT_CURRENT, &extent);
1747 com_err(argv[0], retval, 0);
1751 dbg_print_extent(0, &extent);
1753 printf("Current handle location: %d/%d (max: %d, bytes %d), level %d/%d\n",
1754 info.curr_entry, info.num_entries, info.max_entries,
1755 info.bytes_avail, info.curr_level, info.max_depth);
1756 printf("\tmax lblk: %llu, max pblk: %llu\n", info.max_lblk,
1758 printf("\tmax_len: %u, max_uninit_len: %u\n", info.max_len,
1759 info.max_uninit_len);
1762 void do_goto_block(int argc, char **argv)
1764 struct ext2fs_extent extent;
1766 int op = EXT2_EXTENT_NEXT_LEAF;
1770 if (common_extent_args_process(argc, argv, 2, 3, "goto_block",
1771 "block [level]", 0))
1774 if (strtoblk(argv[0], argv[1], &blk))
1778 if (strtoblk(argv[0], argv[2], &level))
1781 retval = extent_goto(current_handle, level, (blk64_t) blk);
1784 com_err(argv[0], retval, "while trying to go to block %lu, level %d",
1789 generic_goto_node(argv[0], EXT2_EXTENT_CURRENT);