2 * bmap.c --- logical to physical block mapping
4 * Copyright (C) 1997 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Public
22 #if defined(__GNUC__) && !defined(NO_INLINE_FUNCS)
23 #define _BMAP_INLINE_ __inline__
28 extern errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino,
29 struct ext2_inode *inode,
30 char *block_buf, int bmap_flags,
31 blk_t block, blk_t *phys_blk);
33 #define inode_bmap(inode, nr) ((inode)->i_block[(nr)])
35 static _BMAP_INLINE_ errcode_t block_ind_bmap(ext2_filsys fs, int flags,
36 blk_t ind, char *block_buf,
38 blk_t nr, blk_t *ret_blk)
45 return EXT2_ET_SET_BMAP_NO_IND;
49 retval = io_channel_read_blk(fs->io, ind, 1, block_buf);
53 if (flags & BMAP_SET) {
55 #ifdef WORDS_BIGENDIAN
58 ((blk_t *) block_buf)[nr] = b;
59 return io_channel_write_blk(fs->io, ind, 1, block_buf);
62 b = ((blk_t *) block_buf)[nr];
64 #ifdef WORDS_BIGENDIAN
68 if (!b && (flags & BMAP_ALLOC)) {
69 b = nr ? ((blk_t *) block_buf)[nr-1] : 0;
70 retval = ext2fs_alloc_block(fs, b,
71 block_buf + fs->blocksize, &b);
75 #ifdef WORDS_BIGENDIAN
76 ((blk_t *) block_buf)[nr] = ext2fs_swab32(b);
78 ((blk_t *) block_buf)[nr] = b;
81 retval = io_channel_write_blk(fs->io, ind, 1, block_buf);
92 static _BMAP_INLINE_ errcode_t block_dind_bmap(ext2_filsys fs, int flags,
93 blk_t dind, char *block_buf,
95 blk_t nr, blk_t *ret_blk)
101 addr_per_block = (blk_t) fs->blocksize >> 2;
103 retval = block_ind_bmap(fs, flags & ~BMAP_SET, dind, block_buf,
104 blocks_alloc, nr / addr_per_block, &b);
107 retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
108 nr % addr_per_block, ret_blk);
112 static _BMAP_INLINE_ errcode_t block_tind_bmap(ext2_filsys fs, int flags,
113 blk_t tind, char *block_buf,
115 blk_t nr, blk_t *ret_blk)
119 blk_t addr_per_block;
121 addr_per_block = (blk_t) fs->blocksize >> 2;
123 retval = block_dind_bmap(fs, flags & ~BMAP_SET, tind, block_buf,
124 blocks_alloc, nr / addr_per_block, &b);
127 retval = block_ind_bmap(fs, flags, b, block_buf, blocks_alloc,
128 nr % addr_per_block, ret_blk);
132 errcode_t ext2fs_bmap2(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
133 char *block_buf, int bmap_flags, blk64_t block,
134 int *ret_flags, blk64_t *phys_blk)
136 struct ext2_inode inode_buf;
137 ext2_extent_handle_t handle = 0;
138 blk_t addr_per_block;
141 errcode_t retval = 0;
142 int blocks_alloc = 0, inode_dirty = 0;
144 if (!(bmap_flags & BMAP_SET))
150 /* Read inode structure if necessary */
152 retval = ext2fs_read_inode(fs, ino, &inode_buf);
157 addr_per_block = (blk_t) fs->blocksize >> 2;
159 if (inode->i_flags & EXT4_EXTENTS_FL) {
160 struct ext2fs_extent extent;
163 retval = ext2fs_extent_open2(fs, ino, inode, &handle);
166 if (bmap_flags & BMAP_SET) {
167 retval = ext2fs_extent_set_bmap(handle, block,
171 retval = ext2fs_extent_goto(handle, block);
173 /* If the extent is not found, return phys_blk = 0 */
174 if (retval == EXT2_ET_EXTENT_NOT_FOUND)
178 retval = ext2fs_extent_get(handle, EXT2_EXTENT_CURRENT, &extent);
181 offset = block - extent.e_lblk;
182 if (block >= extent.e_lblk && (offset <= extent.e_len)) {
183 *phys_blk = extent.e_pblk + offset;
184 if (ret_flags && extent.e_flags & EXT2_EXTENT_FLAGS_UNINIT)
185 *ret_flags |= BMAP_RET_UNINIT;
188 if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
189 retval = ext2fs_alloc_block(fs, b, block_buf, &b);
192 retval = ext2fs_extent_set_bmap(handle, block,
196 /* Update inode after setting extent */
197 retval = ext2fs_read_inode(fs, ino, inode);
208 retval = ext2fs_get_array(2, fs->blocksize, &buf);
214 if (block < EXT2_NDIR_BLOCKS) {
215 if (bmap_flags & BMAP_SET) {
217 #ifdef WORDS_BIGENDIAN
218 b = ext2fs_swab32(b);
220 inode_bmap(inode, block) = b;
225 *phys_blk = inode_bmap(inode, block);
226 b = block ? inode_bmap(inode, block-1) : 0;
228 if ((*phys_blk == 0) && (bmap_flags & BMAP_ALLOC)) {
229 retval = ext2fs_alloc_block(fs, b, block_buf, &b);
232 inode_bmap(inode, block) = b;
240 block -= EXT2_NDIR_BLOCKS;
242 if (block < addr_per_block) {
243 b = inode_bmap(inode, EXT2_IND_BLOCK);
245 if (!(bmap_flags & BMAP_ALLOC)) {
246 if (bmap_flags & BMAP_SET)
247 retval = EXT2_ET_SET_BMAP_NO_IND;
251 b = inode_bmap(inode, EXT2_IND_BLOCK-1);
252 retval = ext2fs_alloc_block(fs, b, block_buf, &b);
255 inode_bmap(inode, EXT2_IND_BLOCK) = b;
258 retval = block_ind_bmap(fs, bmap_flags, b, block_buf,
259 &blocks_alloc, block, &blk32);
265 /* Doubly indirect block */
266 block -= addr_per_block;
267 if (block < addr_per_block * addr_per_block) {
268 b = inode_bmap(inode, EXT2_DIND_BLOCK);
270 if (!(bmap_flags & BMAP_ALLOC)) {
271 if (bmap_flags & BMAP_SET)
272 retval = EXT2_ET_SET_BMAP_NO_IND;
276 b = inode_bmap(inode, EXT2_IND_BLOCK);
277 retval = ext2fs_alloc_block(fs, b, block_buf, &b);
280 inode_bmap(inode, EXT2_DIND_BLOCK) = b;
283 retval = block_dind_bmap(fs, bmap_flags, b, block_buf,
284 &blocks_alloc, block, &blk32);
290 /* Triply indirect block */
291 block -= addr_per_block * addr_per_block;
292 b = inode_bmap(inode, EXT2_TIND_BLOCK);
294 if (!(bmap_flags & BMAP_ALLOC)) {
295 if (bmap_flags & BMAP_SET)
296 retval = EXT2_ET_SET_BMAP_NO_IND;
300 b = inode_bmap(inode, EXT2_DIND_BLOCK);
301 retval = ext2fs_alloc_block(fs, b, block_buf, &b);
304 inode_bmap(inode, EXT2_TIND_BLOCK) = b;
307 retval = block_tind_bmap(fs, bmap_flags, b, block_buf,
308 &blocks_alloc, block, &blk32);
313 ext2fs_free_mem(&buf);
315 ext2fs_extent_free(handle);
316 if ((retval == 0) && (blocks_alloc || inode_dirty)) {
317 ext2fs_iblk_add_blocks(fs, inode, blocks_alloc);
318 retval = ext2fs_write_inode(fs, ino, inode);
323 errcode_t ext2fs_bmap(ext2_filsys fs, ext2_ino_t ino, struct ext2_inode *inode,
324 char *block_buf, int bmap_flags, blk_t block,
330 ret = ext2fs_bmap2(fs, ino, inode, block_buf, bmap_flags, block,
334 if (ret_blk >= ((long long) 1 << 32))