diff options
Diffstat (limited to 'fs/ext4/namei.c')
-rw-r--r-- | fs/ext4/namei.c | 130 |
1 files changed, 85 insertions, 45 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 0482495..a5ba1a8 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -165,7 +165,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize, struct dx_hash_info *hinfo, struct dx_map_entry map[]); static void dx_sort_map(struct dx_map_entry *map, unsigned count); static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to, - struct dx_map_entry *offsets, int count); + struct dx_map_entry *offsets, int count, unsigned blocksize); static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize); static void dx_insert_block(struct dx_frame *frame, u32 hash, ext4_lblk_t block); @@ -180,14 +180,38 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry, struct inode *inode); +unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize) +{ + unsigned len = le16_to_cpu(dlen); + + if (len == EXT4_MAX_REC_LEN || len == 0) + return blocksize; + return (len & 65532) | ((len & 3) << 16); +} + +__le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize) +{ + if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3)) + BUG(); + if (len < 65536) + return cpu_to_le16(len); + if (len == blocksize) { + if (blocksize == 65536) + return cpu_to_le16(EXT4_MAX_REC_LEN); + else + return cpu_to_le16(0); + } + return cpu_to_le16((len & 65532) | ((len >> 16) & 3)); +} + /* * p is at least 6 bytes before the end of page */ static inline struct ext4_dir_entry_2 * -ext4_next_entry(struct ext4_dir_entry_2 *p) +ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize) { return (struct ext4_dir_entry_2 *)((char *)p + - ext4_rec_len_from_disk(p->rec_len)); + ext4_rec_len_from_disk(p->rec_len, blocksize)); } /* @@ -294,7 +318,7 @@ static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_ent space += EXT4_DIR_REC_LEN(de->name_len); names++; } - de = ext4_next_entry(de); + de = ext4_next_entry(de, size); } printk("(%i)\n", names); return (struct stats) { names, space, 1 }; @@ -585,7 +609,7 @@ static int htree_dirblock_to_tree(struct file *dir_file, top = (struct ext4_dir_entry_2 *) ((char *) de + dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0)); - for (; de < top; de = ext4_next_entry(de)) { + for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) { if (!ext4_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb)) +((char *)de - bh->b_data))) { @@ -663,7 +687,7 @@ int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, } if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; - de = ext4_next_entry(de); + de = ext4_next_entry(de, dir->i_sb->s_blocksize); if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0) goto errout; count++; @@ -732,7 +756,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize, cond_resched(); } /* XXX: do we need to check rec_len == 0 case? -Chris */ - de = ext4_next_entry(de); + de = ext4_next_entry(de, blocksize); } return count; } @@ -832,7 +856,8 @@ static inline int search_dirblock(struct buffer_head *bh, return 1; } /* prevent looping on a bad block */ - de_len = ext4_rec_len_from_disk(de->rec_len); + de_len = ext4_rec_len_from_disk(de->rec_len, + dir->i_sb->s_blocksize); if (de_len <= 0) return -1; offset += de_len; @@ -996,7 +1021,7 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct q de = (struct ext4_dir_entry_2 *) bh->b_data; top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize - EXT4_DIR_REC_LEN(0)); - for (; de < top; de = ext4_next_entry(de)) { + for (; de < top; de = ext4_next_entry(de, sb->s_blocksize)) { int off = (block << EXT4_BLOCK_SIZE_BITS(sb)) + ((char *) de - bh->b_data); @@ -1109,7 +1134,8 @@ static inline void ext4_set_de_type(struct super_block *sb, * Returns pointer to last entry moved. */ static struct ext4_dir_entry_2 * -dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) +dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count, + unsigned blocksize) { unsigned rec_len = 0; @@ -1118,7 +1144,7 @@ dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) rec_len = EXT4_DIR_REC_LEN(de->name_len); memcpy (to, de, rec_len); ((struct ext4_dir_entry_2 *) to)->rec_len = - ext4_rec_len_to_disk(rec_len); + ext4_rec_len_to_disk(rec_len, blocksize); de->inode = 0; map++; to += rec_len; @@ -1137,12 +1163,12 @@ static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) prev = to = de; while ((char*)de < base + blocksize) { - next = ext4_next_entry(de); + next = ext4_next_entry(de, blocksize); if (de->inode && de->name_len) { rec_len = EXT4_DIR_REC_LEN(de->name_len); if (de > to) memmove(to, de, rec_len); - to->rec_len = ext4_rec_len_to_disk(rec_len); + to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize); prev = to; to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); } @@ -1215,10 +1241,12 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, hash2, split, count-split)); /* Fancy dance to stay within two buffers */ - de2 = dx_move_dirents(data1, data2, map + split, count - split); + de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize); de = dx_pack_dirents(data1, blocksize); - de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de); - de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2); + de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de, + blocksize); + de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2, + blocksize); dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1)); dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1)); @@ -1268,6 +1296,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; unsigned int offset = 0; + unsigned int blocksize = dir->i_sb->s_blocksize; unsigned short reclen; int nlen, rlen, err; char *top; @@ -1275,7 +1304,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, reclen = EXT4_DIR_REC_LEN(namelen); if (!de) { de = (struct ext4_dir_entry_2 *)bh->b_data; - top = bh->b_data + dir->i_sb->s_blocksize - reclen; + top = bh->b_data + blocksize - reclen; while ((char *) de <= top) { if (!ext4_check_dir_entry("ext4_add_entry", dir, de, bh, offset)) { @@ -1287,7 +1316,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, return -EEXIST; } nlen = EXT4_DIR_REC_LEN(de->name_len); - rlen = ext4_rec_len_from_disk(de->rec_len); + rlen = ext4_rec_len_from_disk(de->rec_len, blocksize); if ((de->inode? rlen - nlen: rlen) >= reclen) break; de = (struct ext4_dir_entry_2 *)((char *)de + rlen); @@ -1306,11 +1335,11 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, /* By now the buffer is marked for journaling */ nlen = EXT4_DIR_REC_LEN(de->name_len); - rlen = ext4_rec_len_from_disk(de->rec_len); + rlen = ext4_rec_len_from_disk(de->rec_len, blocksize); if (de->inode) { struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen); - de1->rec_len = ext4_rec_len_to_disk(rlen - nlen); - de->rec_len = ext4_rec_len_to_disk(nlen); + de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, blocksize); + de->rec_len = ext4_rec_len_to_disk(nlen, blocksize); de = de1; } de->file_type = EXT4_FT_UNKNOWN; @@ -1380,7 +1409,7 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, /* The 0th block becomes the root, move the dirents out */ fde = &root->dotdot; de = (struct ext4_dir_entry_2 *)((char *)fde + - ext4_rec_len_from_disk(fde->rec_len)); + ext4_rec_len_from_disk(fde->rec_len, blocksize)); if ((char *) de >= (((char *) root) + blocksize)) { ext4_error(dir->i_sb, __func__, "invalid rec_len for '..' in inode %lu", @@ -1402,12 +1431,14 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, memcpy (data1, de, len); de = (struct ext4_dir_entry_2 *) data1; top = data1 + len; - while ((char *)(de2 = ext4_next_entry(de)) < top) + while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) de = de2; - de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de); + de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de, + blocksize); /* Initialize the root; the dot dirents already exist */ de = (struct ext4_dir_entry_2 *) (&root->dotdot); - de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2)); + de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2), + blocksize); memset (&root->info, 0, sizeof(root->info)); root->info.info_length = sizeof(root->info); root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; @@ -1488,7 +1519,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, return retval; de = (struct ext4_dir_entry_2 *) bh->b_data; de->inode = 0; - de->rec_len = ext4_rec_len_to_disk(blocksize); + de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize); return add_dirent_to_buf(handle, dentry, inode, de, bh); } @@ -1551,7 +1582,8 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry, goto cleanup; node2 = (struct dx_node *)(bh2->b_data); entries2 = node2->entries; - node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize); + node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, + sb->s_blocksize); node2->fake.inode = 0; BUFFER_TRACE(frame->bh, "get_write_access"); err = ext4_journal_get_write_access(handle, frame->bh); @@ -1639,6 +1671,7 @@ static int ext4_delete_entry(handle_t *handle, struct buffer_head *bh) { struct ext4_dir_entry_2 *de, *pde; + unsigned int blocksize = dir->i_sb->s_blocksize; int i; i = 0; @@ -1652,8 +1685,11 @@ static int ext4_delete_entry(handle_t *handle, ext4_journal_get_write_access(handle, bh); if (pde) pde->rec_len = ext4_rec_len_to_disk( - ext4_rec_len_from_disk(pde->rec_len) + - ext4_rec_len_from_disk(de->rec_len)); + ext4_rec_len_from_disk(pde->rec_len, + blocksize) + + ext4_rec_len_from_disk(de->rec_len, + blocksize), + blocksize); else de->inode = 0; dir->i_version++; @@ -1661,9 +1697,9 @@ static int ext4_delete_entry(handle_t *handle, ext4_handle_dirty_metadata(handle, dir, bh); return 0; } - i += ext4_rec_len_from_disk(de->rec_len); + i += ext4_rec_len_from_disk(de->rec_len, blocksize); pde = de; - de = ext4_next_entry(de); + de = ext4_next_entry(de, blocksize); } return -ENOENT; } @@ -1793,6 +1829,7 @@ static int ext4_mkdir(struct inode *dir, struct dentry *dentry, int mode) struct inode *inode; struct buffer_head *dir_block; struct ext4_dir_entry_2 *de; + unsigned int blocksize = dir->i_sb->s_blocksize; int err, retries = 0; if (EXT4_DIR_LINK_MAX(dir)) @@ -1824,13 +1861,14 @@ retry: de = (struct ext4_dir_entry_2 *) dir_block->b_data; de->inode = cpu_to_le32(inode->i_ino); de->name_len = 1; - de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len)); + de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len), + blocksize); strcpy(de->name, "."); ext4_set_de_type(dir->i_sb, de, S_IFDIR); - de = ext4_next_entry(de); + de = ext4_next_entry(de, blocksize); de->inode = cpu_to_le32(dir->i_ino); - de->rec_len = ext4_rec_len_to_disk(inode->i_sb->s_blocksize - - EXT4_DIR_REC_LEN(1)); + de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(1), + blocksize); de->name_len = 2; strcpy(de->name, ".."); ext4_set_de_type(dir->i_sb, de, S_IFDIR); @@ -1885,7 +1923,7 @@ static int empty_dir(struct inode *inode) return 1; } de = (struct ext4_dir_entry_2 *) bh->b_data; - de1 = ext4_next_entry(de); + de1 = ext4_next_entry(de, sb->s_blocksize); if (le32_to_cpu(de->inode) != inode->i_ino || !le32_to_cpu(de1->inode) || strcmp(".", de->name) || @@ -1896,9 +1934,9 @@ static int empty_dir(struct inode *inode) brelse(bh); return 1; } - offset = ext4_rec_len_from_disk(de->rec_len) + - ext4_rec_len_from_disk(de1->rec_len); - de = ext4_next_entry(de1); + offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) + + ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize); + de = ext4_next_entry(de1, sb->s_blocksize); while (offset < inode->i_size) { if (!bh || (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { @@ -1927,8 +1965,8 @@ static int empty_dir(struct inode *inode) brelse(bh); return 0; } - offset += ext4_rec_len_from_disk(de->rec_len); - de = ext4_next_entry(de); + offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); + de = ext4_next_entry(de, sb->s_blocksize); } brelse(bh); return 1; @@ -2297,8 +2335,8 @@ retry: return err; } -#define PARENT_INO(buffer) \ - (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer))->inode) +#define PARENT_INO(buffer, size) \ + (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer), size)->inode) /* * Anybody can rename anything with this: the permission checks are left to the @@ -2358,7 +2396,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, dir_bh = ext4_bread(handle, old_inode, 0, 0, &retval); if (!dir_bh) goto end_rename; - if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino) + if (le32_to_cpu(PARENT_INO(dir_bh->b_data, + old_dir->i_sb->s_blocksize)) != old_dir->i_ino) goto end_rename; retval = -EMLINK; if (!new_inode && new_dir != old_dir && @@ -2430,7 +2469,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, if (dir_bh) { BUFFER_TRACE(dir_bh, "get_write_access"); ext4_journal_get_write_access(handle, dir_bh); - PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); + PARENT_INO(dir_bh->b_data, new_dir->i_sb->s_blocksize) = + cpu_to_le32(new_dir->i_ino); BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata"); ext4_handle_dirty_metadata(handle, old_dir, dir_bh); ext4_dec_count(handle, old_dir); |