/* * linux/fs/ext3/namei.c * * Copyright (C) 1992, 1993, 1994, 1995 * Remy Card (card@masi.ibp.fr) * Laboratoire MASI - Institut Blaise Pascal * Universite Pierre et Marie Curie (Paris VI) * * from * * linux/fs/minix/namei.c * * Copyright (C) 1991, 1992 Linus Torvalds * * Big-endian to little-endian byte-swapping/bitmaps by * David S. Miller (davem@caip.rutgers.edu), 1995 * Directory entry file type support and forward compatibility hooks * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998 * Hash Tree Directory indexing (c) * Daniel Phillips, 2001 * Hash Tree Directory indexing porting * Christopher Li, 2002 * Hash Tree Directory indexing cleanup * Theodore Ts'o, 2002 */ #include #include #include #include #include #include #include #include #include #include #include #include #include "namei.h" #include "xattr.h" #include "acl.h" /* * define how far ahead to read directories while searching them. */ #define NAMEI_RA_CHUNKS 2 #define NAMEI_RA_BLOCKS 4 #define NAMEI_RA_SIZE (NAMEI_RA_CHUNKS * NAMEI_RA_BLOCKS) #define NAMEI_RA_INDEX(c,b) (((c) * NAMEI_RA_BLOCKS) + (b)) static struct buffer_head *ext3_append(handle_t *handle, struct inode *inode, u32 *block, int *err) { struct buffer_head *bh; *block = inode->i_size >> inode->i_sb->s_blocksize_bits; if ((bh = ext3_bread(handle, inode, *block, 1, err))) { inode->i_size += inode->i_sb->s_blocksize; EXT3_I(inode)->i_disksize = inode->i_size; ext3_journal_get_write_access(handle,bh); } return bh; } #ifndef assert #define assert(test) J_ASSERT(test) #endif #ifndef swap #define swap(x, y) do { typeof(x) z = x; x = y; y = z; } while (0) #endif #ifdef DX_DEBUG #define dxtrace(command) command #else #define dxtrace(command) #endif struct fake_dirent { __le32 inode; __le16 rec_len; u8 name_len; u8 file_type; }; struct dx_countlimit { __le16 limit; __le16 count; }; struct dx_entry { __le32 hash; __le32 block; }; /* * dx_root_info is laid out so that if it should somehow get overlaid by a * dirent the two low bits of the hash version will be zero. Therefore, the * hash version mod 4 should never be 0. Sincerely, the paranoia department. */ struct dx_root { struct fake_dirent dot; char dot_name[4]; struct fake_dirent dotdot; char dotdot_name[4]; struct dx_root_info { __le32 reserved_zero; u8 hash_version; u8 info_length; /* 8 */ u8 indirect_levels; u8 unused_flags; } info; struct dx_entry entries[0]; }; struct dx_node { struct fake_dirent fake; struct dx_entry entries[0]; }; struct dx_frame { struct buffer_head *bh; struct dx_entry *entries; struct dx_entry *at; }; struct dx_map_entry { u32 hash; u32 offs; }; #ifdef CONFIG_EXT3_INDEX static inline unsigned dx_get_block (struct dx_entry *entry); static void dx_set_block (struct dx_entry *entry, unsigned value); static inline unsigned dx_get_hash (struct dx_entry *entry); static void dx_set_hash (struct dx_entry *entry, unsigned value); static unsigned dx_get_count (struct dx_entry *entries); static unsigned dx_get_limit (struct dx_entry *entries); static void dx_set_count (struct dx_entry *entries, unsigned value); static void dx_set_limit (struct dx_entry *entries, unsigned value); static unsigned dx_root_limit (struct inode *dir, unsigned infosize); static unsigned dx_node_limit (struct inode *dir); static struct dx_frame *dx_probe(struct dentry *dentry, struct inode *dir, struct dx_hash_info *hinfo, struct dx_frame *frame, int *err); static void dx_release (struct dx_frame *frames); static int dx_make_map (struct ext3_dir_entry_2 *de, int size, struct dx_hash_info *hinfo, struct dx_map_entry map[]); static void dx_sort_map(struct dx_map_entry *map, unsigned count); static struct ext3_dir_entry_2 *dx_move_dirents (char *from, char *to, struct dx_map_entry *offsets, int count); static struct ext3_dir_entry_2* dx_pack_dirents (char *base, int size); static void dx_insert_block (struct dx_frame *frame, u32 hash, u32 block); static int ext3_htree_next_block(struct inode *dir, __u32 hash, struct dx_frame *frame, struct dx_frame *frames, __u32 *start_hash); static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, struct ext3_dir_entry_2 **res_dir, int *err); static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, struct inode *inode); /* * Future: use high four bits of block for coalesce-on-delete flags * Mask them off for now. */ static inline unsigned dx_get_block (struct dx_entry *entry) { return le32_to_cpu(entry->block) & 0x00ffffff; } static inline void dx_set_block (struct dx_entry *entry, unsigned value) { entry->block = cpu_to_le32(value); } static inline unsigned dx_get_hash (struct dx_entry *entry) { return le32_to_cpu(entry->hash); } static inline void dx_set_hash (struct dx_entry *entry, unsigned value) { entry->hash = cpu_to_le32(value); } static inline unsigned dx_get_count (struct dx_entry *entries) { return le16_to_cpu(((struct dx_countlimit *) entries)->count); } static inline unsigned dx_get_limit (struct dx_entry *entries) { return le16_to_cpu(((struct dx_countlimit *) entries)->limit); } static inline void dx_set_count (struct dx_entry *entries, unsigned value) { ((struct dx_countlimit *) entries)->count = cpu_to_le16(value); } static inline void dx_set_limit (struct dx_entry *entries, unsigned value) { ((struct dx_countlimit *) entries)->limit = cpu_to_le16(value); } static inline unsigned dx_root_limit (struct inode *dir, unsigned infosize) { unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(1) - EXT3_DIR_REC_LEN(2) - infosize; return 0? 20: entry_space / sizeof(struct dx_entry); } static inline unsigned dx_node_limit (struct inode *dir) { unsigned entry_space = dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0); return 0? 22: entry_space / sizeof(struct dx_entry); } /* * Debug */ #ifdef DX_DEBUG static void dx_show_index (char * label, struct dx_entry *entries) { int i, n = dx_get_count (entries); printk("%s index ", label); for (i = 0; i < n; i++) { printk("%x->%u ", i? dx_get_hash(entries + i): 0, dx_get_block(entries + i)); } printk("\n"); } struct stats { unsigned names; unsigned space; unsigned bcount; }; static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext3_dir_entry_2 *de, int size, int show_names) { unsigned names = 0, space = 0; char *base = (char *) de; struct dx_hash_info h = *hinfo; printk("names: "); while ((char *) de < base + size) { if (de->inode) { if (show_names) { int len = de->name_len; char *name = de->name; while (len--) printk("%c", *name++); ext3fs_dirhash(de->name, de->name_len, &h); printk(":%x.%u ", h.hash, ((char *) de - base)); } space += EXT3_DIR_REC_LEN(de->name_len); names++; } de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } printk("(%i)\n", names); return (struct stats) { names, space, 1 }; } struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir, struct dx_entry *entries, int levels) { unsigned blocksize = dir->i_sb->s_blocksize; unsigned count = dx_get_count (entries), names = 0, space = 0, i; unsigned bcount = 0; struct buffer_head *bh; int err; printk("%i indexed blocks...\n", count); for (i = 0; i < count; i++, entries++) { u32 block = dx_get_block(entries), hash = i? dx_get_hash(entries): 0; u32 range = i < count - 1? (dx_get_hash(entries + 1) - hash): ~hash; struct stats stats; printk("%s%3u:%03u hash %8x/%8x ",levels?"":" ", i, block, hash, range); if (!(bh = ext3_bread (NULL,dir, block, 0,&err))) continue; stats = levels? dx_show_entries(hinfo, dir, ((struct dx_node *) bh->b_data)->entries, levels - 1): dx_show_leaf(hinfo, (struct ext3_dir_entry_2 *) bh->b_data, blocksize, 0); names += stats.names; space += stats.space; bcount += stats.bcount; brelse (bh); } if (bcount) printk("%snames %u, fullness %u (%u%%)\n", levels?"":" ", names, space/bcount,(space/bcount)*100/blocksize); return (struct stats) { names, space, bcount}; } #endif /* DX_DEBUG */ /* * Probe for a directory leaf block to search. * * dx_probe can return ERR_BAD_DX_DIR, which means there was a format * error in the directory index, and the caller should fall back to * searching the directory normally. The callers of dx_probe **MUST** * check for this error code, and make sure it never gets reflected * back to userspace. */ static struct dx_frame * dx_probe(struct dentry *dentry, struct inode *dir, struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err) { unsigned count, indirect; struct dx_entry *at, *entries, *p, *q, *m; struct dx_root *root; struct buffer_head *bh; struct dx_frame *frame = frame_in; u32 hash; frame->bh = NULL; if (dentry) dir = dentry->d_parent->d_inode; if (!(bh = ext3_bread (NULL,dir, 0, 0, err))) goto fail; root = (struct dx_root *) bh->b_data; if (root->info.hash_version != DX_HASH_TEA && root->info.hash_version != DX_HASH_HALF_MD4 && root->info.hash_version != DX_HASH_LEGACY) { ext3_warning(dir->i_sb, __FUNCTION__, "Unrecognised inode hash code %d", root->info.hash_version); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } hinfo->hash_version = root->info.hash_version; hinfo->seed = EXT3_SB(dir->i_sb)->s_hash_seed; if (dentry) ext3fs_dirhash(dentry->d_name.name, dentry->d_name.len, hinfo); hash = hinfo->hash; if (root->info.unused_flags & 1) { ext3_warning(dir->i_sb, __FUNCTION__, "Unimplemented inode hash flags: %#06x", root->info.unused_flags); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } if ((indirect = root->info.indirect_levels) > 1) { ext3_warning(dir->i_sb, __FUNCTION__, "Unimplemented inode hash depth: %#06x", root->info.indirect_levels); brelse(bh); *err = ERR_BAD_DX_DIR; goto fail; } entries = (struct dx_entry *) (((char *)&root->info) + root->info.info_length); assert(dx_get_limit(entries) == dx_root_limit(dir, root->info.info_length)); dxtrace (printk("Look up %x", hash)); while (1) { count = dx_get_count(entries); assert (count && count <= dx_get_limit(entries)); p = entries + 1; q = entries + count - 1; while (p <= q) { m = p + (q - p)/2; dxtrace(printk(".")); if (dx_get_hash(m) > hash) q = m - 1; else p = m + 1; } if (0) // linear search cross check { unsigned n = count - 1; at = entries; while (n--) { dxtrace(printk(",")); if (dx_get_hash(++at) > hash) { at--; break; } } assert (at == p - 1); } at = p - 1; dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at))); frame->bh = bh; frame->entries = entries; frame->at = at; if (!indirect--) return frame; if (!(bh = ext3_bread (NULL,dir, dx_get_block(at), 0, err))) goto fail2; at = entries = ((struct dx_node *) bh->b_data)->entries; assert (dx_get_limit(entries) == dx_node_limit (dir)); frame++; } fail2: while (frame >= frame_in) { brelse(frame->bh); frame--; } fail: return NULL; } static void dx_release (struct dx_frame *frames) { if (frames[0].bh == NULL) return; if (((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels) brelse(frames[1].bh); brelse(frames[0].bh); } /* * This function increments the frame pointer to search the next leaf * block, and reads in the necessary intervening nodes if the search * should be necessary. Whether or not the search is necessary is * controlled by the hash parameter. If the hash value is even, then * the search is only continued if the next block starts with that * hash value. This is used if we are searching for a specific file. * * If the hash value is HASH_NB_ALWAYS, then always go to the next block. * * This function returns 1 if the caller should continue to search, * or 0 if it should not. If there is an error reading one of the * index blocks, it will a negative error code. * * If start_hash is non-null, it will be filled in with the starting * hash of the next page. */ static int ext3_htree_next_block(struct inode *dir, __u32 hash, struct dx_frame *frame, struct dx_frame *frames, __u32 *start_hash) { struct dx_frame *p; struct buffer_head *bh; int err, num_frames = 0; __u32 bhash; p = frame; /* * Find the next leaf page by incrementing the frame pointer. * If we run out of entries in the interior node, loop around and * increment pointer in the parent node. When we break out of * this loop, num_frames indicates the number of interior * nodes need to be read. */ while (1) { if (++(p->at) < p->entries + dx_get_count(p->entries)) break; if (p == frames) return 0; num_frames++; p--; } /* * If the hash is 1, then continue only if the next page has a * continuation hash of any value. This is used for readdir * handling. Otherwise, check to see if the hash matches the * desired contiuation hash. If it doesn't, return since * there's no point to read in the successive index pages. */ bhash = dx_get_hash(p->at); if (start_hash) *start_hash = bhash; if ((hash & 1) == 0) { if ((bhash & ~1) != hash) return 0; } /* * If the hash is HASH_NB_ALWAYS, we always go to the next * block so no check is necessary */ while (num_frames--) { if (!(bh = ext3_bread(NULL, dir, dx_get_block(p->at), 0, &err))) return err; /* Failure */ p++; brelse (p->bh); p->bh = bh; p->at = p->entries = ((struct dx_node *) bh->b_data)->entries; } return 1; } /* * p is at least 6 bytes before the end of page */ static inline struct ext3_dir_entry_2 *ext3_next_entry(struct ext3_dir_entry_2 *p) { return (struct ext3_dir_entry_2 *)((char*)p + le16_to_cpu(p->rec_len)); } /* * This function fills a red-black tree with information from a * directory block. It returns the number directory entries loaded * into the tree. If there is an error it is returned in err. */ static int htree_dirblock_to_tree(struct file *dir_file, struct inode *dir, int block, struct dx_hash_info *hinfo, __u32 start_hash, __u32 start_minor_hash) { struct buffer_head *bh; struct ext3_dir_entry_2 *de, *top; int err, count = 0; dxtrace(printk("In htree dirblock_to_tree: block %d\n", block)); if (!(bh = ext3_bread (NULL, dir, block, 0, &err))) return err; de = (struct ext3_dir_entry_2 *) bh->b_data; top = (struct ext3_dir_entry_2 *) ((char *) de + dir->i_sb->s_blocksize - EXT3_DIR_REC_LEN(0)); for (; de < top; de = ext3_next_entry(de)) { if (!ext3_check_dir_entry("htree_dirblock_to_tree", dir, de, bh, (block<i_sb)) +((char *)de - bh->b_data))) { /* On error, skip the f_pos to the next block. */ dir_file->f_pos = (dir_file->f_pos | (dir->i_sb->s_blocksize - 1)) + 1; brelse (bh); return count; } ext3fs_dirhash(de->name, de->name_len, hinfo); if ((hinfo->hash < start_hash) || ((hinfo->hash == start_hash) && (hinfo->minor_hash < start_minor_hash))) continue; if (de->inode == 0) continue; if ((err = ext3_htree_store_dirent(dir_file, hinfo->hash, hinfo->minor_hash, de)) != 0) { brelse(bh); return err; } count++; } brelse(bh); return count; } /* * This function fills a red-black tree with information from a * directory. We start scanning the directory in hash order, starting * at start_hash and start_minor_hash. * * This function returns the number of entries inserted into the tree, * or a negative error code. */ int ext3_htree_fill_tree(struct file *dir_file, __u32 start_hash, __u32 start_minor_hash, __u32 *next_hash) { struct dx_hash_info hinfo; struct ext3_dir_entry_2 *de; struct dx_frame frames[2], *frame; struct inode *dir; int block, err; int count = 0; int ret; __u32 hashval; dxtrace(printk("In htree_fill_tree, start hash: %x:%x\n", start_hash, start_minor_hash)); dir = dir_file->f_dentry->d_inode; if (!(EXT3_I(dir)->i_flags & EXT3_INDEX_FL)) { hinfo.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; count = htree_dirblock_to_tree(dir_file, dir, 0, &hinfo, start_hash, start_minor_hash); *next_hash = ~0; return count; } hinfo.hash = start_hash; hinfo.minor_hash = 0; frame = dx_probe(NULL, dir_file->f_dentry->d_inode, &hinfo, frames, &err); if (!frame) return err; /* Add '.' and '..' from the htree header */ if (!start_hash && !start_minor_hash) { de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; if ((err = ext3_htree_store_dirent(dir_file, 0, 0, de)) != 0) goto errout; count++; } if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) { de = (struct ext3_dir_entry_2 *) frames[0].bh->b_data; de = ext3_next_entry(de); if ((err = ext3_htree_store_dirent(dir_file, 2, 0, de)) != 0) goto errout; count++; } while (1) { block = dx_get_block(frame->at); ret = htree_dirblock_to_tree(dir_file, dir, block, &hinfo, start_hash, start_minor_hash); if (ret < 0) { err = ret; goto errout; } count += ret; hashval = ~0; ret = ext3_htree_next_block(dir, HASH_NB_ALWAYS, frame, frames, &hashval); *next_hash = hashval; if (ret < 0) { err = ret; goto errout; } /* * Stop if: (a) there are no more entries, or * (b) we have inserted at least one entry and the * next hash value is not a continuation */ if ((ret == 0) || (count && ((hashval & 1) == 0))) break; } dx_release(frames); dxtrace(printk("Fill tree: returned %d entries, next hash: %x\n", count, *next_hash)); return count; errout: dx_release(frames); return (err); } /* * Directory block splitting, compacting */ static int dx_make_map (struct ext3_dir_entry_2 *de, int size, struct dx_hash_info *hinfo, struct dx_map_entry *map_tail) { int count = 0; char *base = (char *) de; struct dx_hash_info h = *hinfo; while ((char *) de < base + size) { if (de->name_len && de->inode) { ext3fs_dirhash(de->name, de->name_len, &h); map_tail--; map_tail->hash = h.hash; map_tail->offs = (u32) ((char *) de - base); count++; cond_resched(); } /* XXX: do we need to check rec_len == 0 case? -Chris */ de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } return count; } static void dx_sort_map (struct dx_map_entry *map, unsigned count) { struct dx_map_entry *p, *q, *top = map + count - 1; int more; /* Combsort until bubble sort doesn't suck */ while (count > 2) { count = count*10/13; if (count - 9 < 2) /* 9, 10 -> 11 */ count = 11; for (p = top, q = p - count; q >= map; p--, q--) if (p->hash < q->hash) swap(*p, *q); } /* Garden variety bubble sort */ do { more = 0; q = top; while (q-- > map) { if (q[1].hash >= q[0].hash) continue; swap(*(q+1), *q); more = 1; } } while(more); } static void dx_insert_block(struct dx_frame *frame, u32 hash, u32 block) { struct dx_entry *entries = frame->entries; struct dx_entry *old = frame->at, *new = old + 1; int count = dx_get_count(entries); assert(count < dx_get_limit(entries)); assert(old < entries + count); memmove(new + 1, new, (char *)(entries + count) - (char *)(new)); dx_set_hash(new, hash); dx_set_block(new, block); dx_set_count(entries, count + 1); } #endif static void ext3_update_dx_flag(struct inode *inode) { if (!EXT3_HAS_COMPAT_FEATURE(inode->i_sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) EXT3_I(inode)->i_flags &= ~EXT3_INDEX_FL; } /* * NOTE! unlike strncmp, ext3_match returns 1 for success, 0 for failure. * * `len <= EXT3_NAME_LEN' is guaranteed by caller. * `de != NULL' is guaranteed by caller. */ static inline int ext3_match (int len, const char * const name, struct ext3_dir_entry_2 * de) { if (len != de->name_len) return 0; if (!de->inode) return 0; return !memcmp(name, de->name, len); } /* * Returns 0 if not found, -1 on failure, and 1 on success */ static inline int search_dirblock(struct buffer_head * bh, struct inode *dir, struct dentry *dentry, unsigned long offset, struct ext3_dir_entry_2 ** res_dir) { struct ext3_dir_entry_2 * de; char * dlimit; int de_len; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; de = (struct ext3_dir_entry_2 *) bh->b_data; dlimit = bh->b_data + dir->i_sb->s_blocksize; while ((char *) de < dlimit) { /* this code is executed quadratically often */ /* do minimal checking `by hand' */ if ((char *) de + namelen <= dlimit && ext3_match (namelen, name, de)) { /* found a match - just to be sure, do a full check */ if (!ext3_check_dir_entry("ext3_find_entry", dir, de, bh, offset)) return -1; *res_dir = de; return 1; } /* prevent looping on a bad block */ de_len = le16_to_cpu(de->rec_len); if (de_len <= 0) return -1; offset += de_len; de = (struct ext3_dir_entry_2 *) ((char *) de + de_len); } return 0; } /* * ext3_find_entry() * * finds an entry in the specified directory with the wanted name. It * returns the cache buffer in which the entry was found, and the entry * itself (as a parameter - res_dir). It does NOT read the inode of the * entry - you'll have to do that yourself if you want to. * * The returned buffer_head has ->b_count elevated. The caller is expected * to brelse() it when appropriate. */ static struct buffer_head * ext3_find_entry (struct dentry *dentry, struct ext3_dir_entry_2 ** res_dir) { struct super_block * sb; struct buffer_head * bh_use[NAMEI_RA_SIZE]; struct buffer_head * bh, *ret = NULL; unsigned long start, block, b; int ra_max = 0; /* Number of bh's in the readahead buffer, bh_use[] */ int ra_ptr = 0; /* Current index into readahead buffer */ int num = 0; int nblocks, i, err; struct inode *dir = dentry->d_parent->d_inode; int namelen; const u8 *name; unsigned blocksize; *res_dir = NULL; sb = dir->i_sb; blocksize = sb->s_blocksize; namelen = dentry->d_name.len; name = dentry->d_name.name; if (namelen > EXT3_NAME_LEN) return NULL; #ifdef CONFIG_EXT3_INDEX if (is_dx(dir)) { bh = ext3_dx_find_entry(dentry, res_dir, &err); /* * On success, or if the error was file not found, * return. Otherwise, fall back to doing a search the * old fashioned way. */ if (bh || (err != ERR_BAD_DX_DIR)) return bh; dxtrace(printk("ext3_find_entry: dx failed, falling back\n")); } #endif nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); start = EXT3_I(dir)->i_dir_start_lookup; if (start >= nblocks) start = 0; block = start; restart: do { /* * We deal with the read-ahead logic here. */ if (ra_ptr >= ra_max) { /* Refill the readahead buffer */ ra_ptr = 0; b = block; for (ra_max = 0; ra_max < NAMEI_RA_SIZE; ra_max++) { /* * Terminate if we reach the end of the * directory and must wrap, or if our * search has finished at this block. */ if (b >= nblocks || (num && block == start)) { bh_use[ra_max] = NULL; break; } num++; bh = ext3_getblk(NULL, dir, b++, 0, &err); bh_use[ra_max] = bh; if (bh) ll_rw_block(READ, 1, &bh); } } if ((bh = bh_use[ra_ptr++]) == NULL) goto next; wait_on_buffer(bh); if (!buffer_uptodate(bh)) { /* read error, skip block & hope for the best */ ext3_error(sb, __FUNCTION__, "reading directory #%lu " "offset %lu", dir->i_ino, block); brelse(bh); goto next; } i = search_dirblock(bh, dir, dentry, block << EXT3_BLOCK_SIZE_BITS(sb), res_dir); if (i == 1) { EXT3_I(dir)->i_dir_start_lookup = block; ret = bh; goto cleanup_and_exit; } else { brelse(bh); if (i < 0) goto cleanup_and_exit; } next: if (++block >= nblocks) block = 0; } while (block != start); /* * If the directory has grown while we were searching, then * search the last part of the directory before giving up. */ block = nblocks; nblocks = dir->i_size >> EXT3_BLOCK_SIZE_BITS(sb); if (block < nblocks) { start = 0; goto restart; } cleanup_and_exit: /* Clean up the read-ahead blocks */ for (; ra_ptr < ra_max; ra_ptr++) brelse (bh_use[ra_ptr]); return ret; } #ifdef CONFIG_EXT3_INDEX static struct buffer_head * ext3_dx_find_entry(struct dentry *dentry, struct ext3_dir_entry_2 **res_dir, int *err) { struct super_block * sb; struct dx_hash_info hinfo; u32 hash; struct dx_frame frames[2], *frame; struct ext3_dir_entry_2 *de, *top; struct buffer_head *bh; unsigned long block; int retval; int namelen = dentry->d_name.len; const u8 *name = dentry->d_name.name; struct inode *dir = dentry->d_parent->d_inode; sb = dir->i_sb; /* NFS may look up ".." - look at dx_root directory block */ if (namelen > 2 || name[0] != '.'||(name[1] != '.' && name[1] != '\0')){ if (!(frame = dx_probe(dentry, NULL, &hinfo, frames, err))) return NULL; } else { frame = frames; frame->bh = NULL; /* for dx_release() */ frame->at = (struct dx_entry *)frames; /* hack for zero entry*/ dx_set_block(frame->at, 0); /* dx_root block is 0 */ } hash = hinfo.hash; do { block = dx_get_block(frame->at); if (!(bh = ext3_bread (NULL,dir, block, 0, err))) goto errout; de = (struct ext3_dir_entry_2 *) bh->b_data; top = (struct ext3_dir_entry_2 *) ((char *) de + sb->s_blocksize - EXT3_DIR_REC_LEN(0)); for (; de < top; de = ext3_next_entry(de)) if (ext3_match (namelen, name, de)) { if (!ext3_check_dir_entry("ext3_find_entry", dir, de, bh, (block<b_data))) { brelse (bh); goto errout; } *res_dir = de; dx_release (frames); return bh; } brelse (bh); /* Check to see if we should continue to search */ retval = ext3_htree_next_block(dir, hash, frame, frames, NULL); if (retval < 0) { ext3_warning(sb, __FUNCTION__, "error reading index page in directory #%lu", dir->i_ino); *err = retval; goto errout; } } while (retval == 1); *err = -ENOENT; errout: dxtrace(printk("%s not found\n", name)); dx_release (frames); return NULL; } #endif static struct dentry *ext3_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd) { struct inode * inode; struct ext3_dir_entry_2 * de; struct buffer_head * bh; if (dentry->d_name.len > EXT3_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); bh = ext3_find_entry(dentry, &de); inode = NULL; if (bh) { unsigned long ino = le32_to_cpu(de->inode); brelse (bh); if (!ext3_valid_inum(dir->i_sb, ino)) { ext3_error(dir->i_sb, "ext3_lookup", "bad inode number: %lu", ino); inode = NULL; } else inode = iget(dir->i_sb, ino); if (!inode) return ERR_PTR(-EACCES); } return d_splice_alias(inode, dentry); } struct dentry *ext3_get_parent(struct dentry *child) { unsigned long ino; struct dentry *parent; struct inode *inode; struct dentry dotdot; struct ext3_dir_entry_2 * de; struct buffer_head *bh; dotdot.d_name.name = ".."; dotdot.d_name.len = 2; dotdot.d_parent = child; /* confusing, isn't it! */ bh = ext3_find_entry(&dotdot, &de); inode = NULL; if (!bh) return ERR_PTR(-ENOENT); ino = le32_to_cpu(de->inode); brelse(bh); if (!ext3_valid_inum(child->d_inode->i_sb, ino)) { ext3_error(child->d_inode->i_sb, "ext3_get_parent", "bad inode number: %lu", ino); inode = NULL; } else inode = iget(child->d_inode->i_sb, ino); if (!inode) return ERR_PTR(-EACCES); parent = d_alloc_anon(inode); if (!parent) { iput(inode); parent = ERR_PTR(-ENOMEM); } return parent; } #define S_SHIFT 12 static unsigned char ext3_type_by_mode[S_IFMT >> S_SHIFT] = { [S_IFREG >> S_SHIFT] = EXT3_FT_REG_FILE, [S_IFDIR >> S_SHIFT] = EXT3_FT_DIR, [S_IFCHR >> S_SHIFT] = EXT3_FT_CHRDEV, [S_IFBLK >> S_SHIFT] = EXT3_FT_BLKDEV, [S_IFIFO >> S_SHIFT] = EXT3_FT_FIFO, [S_IFSOCK >> S_SHIFT] = EXT3_FT_SOCK, [S_IFLNK >> S_SHIFT] = EXT3_FT_SYMLINK, }; static inline void ext3_set_de_type(struct super_block *sb, struct ext3_dir_entry_2 *de, umode_t mode) { if (EXT3_HAS_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) de->file_type = ext3_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; } #ifdef CONFIG_EXT3_INDEX static struct ext3_dir_entry_2 * dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count) { unsigned rec_len = 0; while (count--) { struct ext3_dir_entry_2 *de = (struct ext3_dir_entry_2 *) (from + map->offs); rec_len = EXT3_DIR_REC_LEN(de->name_len); memcpy (to, de, rec_len); ((struct ext3_dir_entry_2 *) to)->rec_len = cpu_to_le16(rec_len); de->inode = 0; map++; to += rec_len; } return (struct ext3_dir_entry_2 *) (to - rec_len); } static struct ext3_dir_entry_2* dx_pack_dirents(char *base, int size) { struct ext3_dir_entry_2 *next, *to, *prev, *de = (struct ext3_dir_entry_2 *) base; unsigned rec_len = 0; prev = to = de; while ((char*)de < base + size) { next = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); if (de->inode && de->name_len) { rec_len = EXT3_DIR_REC_LEN(de->name_len); if (de > to) memmove(to, de, rec_len); to->rec_len = cpu_to_le16(rec_len); prev = to; to = (struct ext3_dir_entry_2 *) (((char *) to) + rec_len); } de = next; } return prev; } static struct ext3_dir_entry_2 *do_split(handle_t *handle, struct inode *dir, struct buffer_head **bh,struct dx_frame *frame, struct dx_hash_info *hinfo, int *error) { unsigned blocksize = dir->i_sb->s_blocksize; unsigned count, continued; struct buffer_head *bh2; u32 newblock; u32 hash2; struct dx_map_entry *map; char *data1 = (*bh)->b_data, *data2; unsigned split; struct ext3_dir_entry_2 *de = NULL, *de2; int err; bh2 = ext3_append (handle, dir, &newblock, error); if (!(bh2)) { brelse(*bh); *bh = NULL; goto errout; } BUFFER_TRACE(*bh, "get_write_access"); err = ext3_journal_get_write_access(handle, *bh); if (err) { journal_error: brelse(*bh); brelse(bh2); *bh = NULL; ext3_std_error(dir->i_sb, err); goto errout; } BUFFER_TRACE(frame->bh, "get_write_access"); err = ext3_journal_get_write_access(handle, frame->bh); if (err) goto journal_error; data2 = bh2->b_data; /* create map in the end of data2 block */ map = (struct dx_map_entry *) (data2 + blocksize); count = dx_make_map ((struct ext3_dir_entry_2 *) data1, blocksize, hinfo, map); map -= count; split = count/2; // need to adjust to actual middle dx_sort_map (map, count); hash2 = map[split].hash; continued = hash2 == map[split - 1].hash; dxtrace(printk("Split block %i at %x, %i/%i\n", dx_get_block(frame->at), hash2, split, count-split)); /* Fancy dance to stay within two buffers */ de2 = dx_move_dirents(data1, data2, map + split, count - split); de = dx_pack_dirents(data1,blocksize); de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de); de2->rec_len = cpu_to_le16(data2 + blocksize - (char *) de2); dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data1, blocksize, 1)); dxtrace(dx_show_leaf (hinfo, (struct ext3_dir_entry_2 *) data2, blocksize, 1)); /* Which block gets the new entry? */ if (hinfo->hash >= hash2) { swap(*bh, bh2); de = de2; } dx_insert_block (frame, hash2 + continued, newblock); err = ext3_journal_dirty_metadata (handle, bh2); if (err) goto journal_error; err = ext3_journal_dirty_metadata (handle, frame->bh); if (err) goto journal_error; brelse (bh2); dxtrace(dx_show_index ("frame", frame->entries)); errout: return de; } #endif /* * Add a new entry into a directory (leaf) block. If de is non-NULL, * it points to a directory entry which is guaranteed to be large * enough for new directory entry. If de is NULL, then * add_dirent_to_buf will attempt search the directory block for * space. It will return -ENOSPC if no space is available, and -EIO * and -EEXIST if directory entry already exists. * * NOTE! bh is NOT released in the case where ENOSPC is returned. In * all other cases bh is released. */ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, struct inode *inode, struct ext3_dir_entry_2 *de, struct buffer_head * bh) { struct inode *dir = dentry->d_parent->d_inode; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; unsigned long offset = 0; unsigned short reclen; int nlen, rlen, err; char *top; reclen = EXT3_DIR_REC_LEN(namelen); if (!de) { de = (struct ext3_dir_entry_2 *)bh->b_data; top = bh->b_data + dir->i_sb->s_blocksize - reclen; while ((char *) de <= top) { if (!ext3_check_dir_entry("ext3_add_entry", dir, de, bh, offset)) { brelse (bh); return -EIO; } if (ext3_match (namelen, name, de)) { brelse (bh); return -EEXIST; } nlen = EXT3_DIR_REC_LEN(de->name_len); rlen = le16_to_cpu(de->rec_len); if ((de->inode? rlen - nlen: rlen) >= reclen) break; de = (struct ext3_dir_entry_2 *)((char *)de + rlen); offset += rlen; } if ((char *) de > top) return -ENOSPC; } BUFFER_TRACE(bh, "get_write_access"); err = ext3_journal_get_write_access(handle, bh); if (err) { ext3_std_error(dir->i_sb, err); brelse(bh); return err; } /* By now the buffer is marked for journaling */ nlen = EXT3_DIR_REC_LEN(de->name_len); rlen = le16_to_cpu(de->rec_len); if (de->inode) { struct ext3_dir_entry_2 *de1 = (struct ext3_dir_entry_2 *)((char *)de + nlen); de1->rec_len = cpu_to_le16(rlen - nlen); de->rec_len = cpu_to_le16(nlen); de = de1; } de->file_type = EXT3_FT_UNKNOWN; if (inode) { de->inode = cpu_to_le32(inode->i_ino); ext3_set_de_type(dir->i_sb, de, inode->i_mode); } else de->inode = 0; de->name_len = namelen; memcpy (de->name, name, namelen); /* * XXX shouldn't update any times until successful * completion of syscall, but too many callers depend * on this. * * XXX similarly, too many callers depend on * ext3_new_inode() setting the times, but error * recovery deletes the inode, so the worst that can * happen is that the times are slightly out of date * and/or different from the directory change time. */ dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC; ext3_update_dx_flag(dir); dir->i_version++; ext3_mark_inode_dirty(handle, dir); BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); err = ext3_journal_dirty_metadata(handle, bh); if (err) ext3_std_error(dir->i_sb, err); brelse(bh); return 0; } #ifdef CONFIG_EXT3_INDEX /* * This converts a one block unindexed directory to a 3 block indexed * directory, and adds the dentry to the indexed directory. */ static int make_indexed_dir(handle_t *handle, struct dentry *dentry, struct inode *inode, struct buffer_head *bh) { struct inode *dir = dentry->d_parent->d_inode; const char *name = dentry->d_name.name; int namelen = dentry->d_name.len; struct buffer_head *bh2; struct dx_root *root; struct dx_frame frames[2], *frame; struct dx_entry *entries; struct ext3_dir_entry_2 *de, *de2; char *data1, *top; unsigned len; int retval; unsigned blocksize; struct dx_hash_info hinfo; u32 block; struct fake_dirent *fde; blocksize = dir->i_sb->s_blocksize; dxtrace(printk("Creating index\n")); retval = ext3_journal_get_write_access(handle, bh); if (retval) { ext3_std_error(dir->i_sb, retval); brelse(bh); return retval; } root = (struct dx_root *) bh->b_data; bh2 = ext3_append (handle, dir, &block, &retval); if (!(bh2)) { brelse(bh); return retval; } EXT3_I(dir)->i_flags |= EXT3_INDEX_FL; data1 = bh2->b_data; /* The 0th block becomes the root, move the dirents out */ fde = &root->dotdot; de = (struct ext3_dir_entry_2 *)((char *)fde + le16_to_cpu(fde->rec_len)); len = ((char *) root) + blocksize - (char *) de; memcpy (data1, de, len); de = (struct ext3_dir_entry_2 *) data1; top = data1 + len; while ((char *)(de2=(void*)de+le16_to_cpu(de->rec_len)) < top) de = de2; de->rec_len = cpu_to_le16(data1 + blocksize - (char *) de); /* Initialize the root; the dot dirents already exist */ de = (struct ext3_dir_entry_2 *) (&root->dotdot); de->rec_len = cpu_to_le16(blocksize - EXT3_DIR_REC_LEN(2)); memset (&root->info, 0, sizeof(root->info)); root->info.info_length = sizeof(root->info); root->info.hash_version = EXT3_SB(dir->i_sb)->s_def_hash_version; entries = root->entries; dx_set_block (entries, 1); dx_set_count (entries, 1); dx_set_limit (entries, dx_root_limit(dir, sizeof(root->info))); /* Initialize as for dx_probe */ hinfo.hash_version = root->info.hash_version; hinfo.seed = EXT3_SB(dir->i_sb)->s_hash_seed; ext3fs_dirhash(name, namelen, &hinfo); frame = frames; frame->entries = entries; frame->at = entries; frame->bh = bh; bh = bh2; de = do_split(handle,dir, &bh, frame, &hinfo, &retval); dx_release (frames); if (!(de)) return retval; return add_dirent_to_buf(handle, dentry, inode, de, bh); } #endif /* * ext3_add_entry() * * adds a file entry to the specified directory, using the same * semantics as ext3_find_entry(). It returns NULL if it failed. * * NOTE!! The inode part of 'de' is left at 0 - which means you * may not sleep between calling this and putting something into * the entry, as someone else might have used it while you slept. */ static int ext3_add_entry (handle_t *handle, struct dentry *dentry, struct inode *inode) { struct inode *dir = dentry->d_parent->d_inode; unsigned long offset; struct buffer_head * bh; struct ext3_dir_entry_2 *de; struct super_block * sb; int retval; #ifdef CONFIG_EXT3_INDEX int dx_fallback=0; #endif unsigned blocksize; unsigned nlen, rlen; u32 block, blocks; sb = dir->i_sb; blocksize = sb->s_blocksize; if (!dentry->d_name.len) return -EINVAL; #ifdef CONFIG_EXT3_INDEX if (is_dx(dir)) { retval = ext3_dx_add_entry(handle, dentry, inode); if (!retval || (retval != ERR_BAD_DX_DIR)) return retval; EXT3_I(dir)->i_flags &= ~EXT3_INDEX_FL; dx_fallback++; ext3_mark_inode_dirty(handle, dir); } #endif blocks = dir->i_size >> sb->s_blocksize_bits; for (block = 0, offset = 0; block < blocks; block++) { bh = ext3_bread(handle, dir, block, 0, &retval); if(!bh) return retval; retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); if (retval != -ENOSPC) return retval; #ifdef CONFIG_EXT3_INDEX if (blocks == 1 && !dx_fallback && EXT3_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_DIR_INDEX)) return make_indexed_dir(handle, dentry, inode, bh); #endif brelse(bh); } bh = ext3_append(handle, dir, &block, &retval); if (!bh) return retval; de = (struct ext3_dir_entry_2 *) bh->b_data; de->inode = 0; de->rec_len = cpu_to_le16(rlen = blocksize); nlen = 0; return add_dirent_to_buf(handle, dentry, inode, de, bh); } #ifdef CONFIG_EXT3_INDEX /* * Returns 0 for success, or a negative error value */ static int ext3_dx_add_entry(handle_t *handle, struct dentry *dentry, struct inode *inode) { struct dx_frame frames[2], *frame; struct dx_entry *entries, *at; struct dx_hash_info hinfo; struct buffer_head * bh; struct inode *dir = dentry->d_parent->d_inode; struct super_block * sb = dir->i_sb; struct ext3_dir_entry_2 *de; int err; frame = dx_probe(dentry, NULL, &hinfo, frames, &err); if (!frame) return err; entries = frame->entries; at = frame->at; if (!(bh = ext3_bread(handle,dir, dx_get_block(frame->at), 0, &err))) goto cleanup; BUFFER_TRACE(bh, "get_write_access"); err = ext3_journal_get_write_access(handle, bh); if (err) goto journal_error; err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); if (err != -ENOSPC) { bh = NULL; goto cleanup; } /* Block full, should compress but for now just split */ dxtrace(printk("using %u of %u node entries\n", dx_get_count(entries), dx_get_limit(entries))); /* Need to split index? */ if (dx_get_count(entries) == dx_get_limit(entries)) { u32 newblock; unsigned icount = dx_get_count(entries); int levels = frame - frames; struct dx_entry *entries2; struct dx_node *node2; struct buffer_head *bh2; if (levels && (dx_get_count(frames->entries) == dx_get_limit(frames->entries))) { ext3_warning(sb, __FUNCTION__, "Directory index full!"); err = -ENOSPC; goto cleanup; } bh2 = ext3_append (handle, dir, &newblock, &err); if (!(bh2)) goto cleanup; node2 = (struct dx_node *)(bh2->b_data); entries2 = node2->entries; node2->fake.rec_len = cpu_to_le16(sb->s_blocksize); node2->fake.inode = 0; BUFFER_TRACE(frame->bh, "get_write_access"); err = ext3_journal_get_write_access(handle, frame->bh); if (err) goto journal_error; if (levels) { unsigned icount1 = icount/2, icount2 = icount - icount1; unsigned hash2 = dx_get_hash(entries + icount1); dxtrace(printk("Split index %i/%i\n", icount1, icount2)); BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ err = ext3_journal_get_write_access(handle, frames[0].bh); if (err) goto journal_error; memcpy ((char *) entries2, (char *) (entries + icount1), icount2 * sizeof(struct dx_entry)); dx_set_count (entries, icount1); dx_set_count (entries2, icount2); dx_set_limit (entries2, dx_node_limit(dir)); /* Which index block gets the new entry? */ if (at - entries >= icount1) { frame->at = at = at - entries - icount1 + entries2; frame->entries = entries = entries2; swap(frame->bh, bh2); } dx_insert_block (frames + 0, hash2, newblock); dxtrace(dx_show_index ("node", frames[1].entries)); dxtrace(dx_show_index ("node", ((struct dx_node *) bh2->b_data)->entries)); err = ext3_journal_dirty_metadata(handle, bh2); if (err) goto journal_error; brelse (bh2); } else { dxtrace(printk("Creating second level index...\n")); memcpy((char *) entries2, (char *) entries, icount * sizeof(struct dx_entry)); dx_set_limit(entries2, dx_node_limit(dir)); /* Set up root */ dx_set_count(entries, 1); dx_set_block(entries + 0, newblock); ((struct dx_root *) frames[0].bh->b_data)->info.indirect_levels = 1; /* Add new access path frame */ frame = frames + 1; frame->at = at = at - entries + entries2; frame->entries = entries = entries2; frame->bh = bh2; err = ext3_journal_get_write_access(handle, frame->bh); if (err) goto journal_error; } ext3_journal_dirty_metadata(handle, frames[0].bh); } de = do_split(handle, dir, &bh, frame, &hinfo, &err); if (!de) goto cleanup; err = add_dirent_to_buf(handle, dentry, inode, de, bh); bh = NULL; goto cleanup; journal_error: ext3_std_error(dir->i_sb, err); cleanup: if (bh) brelse(bh); dx_release(frames); return err; } #endif /* * ext3_delete_entry deletes a directory entry by merging it with the * previous entry */ static int ext3_delete_entry (handle_t *handle, struct inode * dir, struct ext3_dir_entry_2 * de_del, struct buffer_head * bh) { struct ext3_dir_entry_2 * de, * pde; int i; i = 0; pde = NULL; de = (struct ext3_dir_entry_2 *) bh->b_data; while (i < bh->b_size) { if (!ext3_check_dir_entry("ext3_delete_entry", dir, de, bh, i)) return -EIO; if (de == de_del) { BUFFER_TRACE(bh, "get_write_access"); ext3_journal_get_write_access(handle, bh); if (pde) pde->rec_len = cpu_to_le16(le16_to_cpu(pde->rec_len) + le16_to_cpu(de->rec_len)); else de->inode = 0; dir->i_version++; BUFFER_TRACE(bh, "call ext3_journal_dirty_metadata"); ext3_journal_dirty_metadata(handle, bh); return 0; } i += le16_to_cpu(de->rec_len); pde = de; de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } return -ENOENT; } /* * ext3_mark_inode_dirty is somewhat expensive, so unlike ext2 we * do not perform it in these functions. We perform it at the call site, * if it is needed. */ static inline void ext3_inc_count(handle_t *handle, struct inode *inode) { inode->i_nlink++; } static inline void ext3_dec_count(handle_t *handle, struct inode *inode) { inode->i_nlink--; } static int ext3_add_nondir(handle_t *handle, struct dentry *dentry, struct inode *inode) { int err = ext3_add_entry(handle, dentry, inode); if (!err) { ext3_mark_inode_dirty(handle, inode); d_instantiate(dentry, inode); return 0; } ext3_dec_count(handle, inode); iput(inode); return err; } /* * By the time this is called, we already have created * the directory cache entry for the new file, but it * is so far negative - it has no inode. * * If the create succeeds, we fill in the inode information * with d_instantiate(). */ static int ext3_create (struct inode * dir, struct dentry * dentry, int mode, struct nameidata *nd) { handle_t *handle; struct inode * inode; int err, retries = 0; retry: handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode = ext3_new_inode (handle, dir, mode); err = PTR_ERR(inode); if (!IS_ERR(inode)) { inode->i_op = &ext3_file_inode_operations; inode->i_fop = &ext3_file_operations; ext3_set_aops(inode); err = ext3_add_nondir(handle, dentry, inode); } ext3_journal_stop(handle); if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) goto retry; return err; } static int ext3_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev) { handle_t *handle; struct inode *inode; int err, retries = 0; if (!new_valid_dev(rdev)) return -EINVAL; retry: handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode = ext3_new_inode (handle, dir, mode); err = PTR_ERR(inode); if (!IS_ERR(inode)) { init_special_inode(inode, inode->i_mode, rdev); #ifdef CONFIG_EXT3_FS_XATTR inode->i_op = &ext3_special_inode_operations; #endif err = ext3_add_nondir(handle, dentry, inode); } ext3_journal_stop(handle); if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) goto retry; return err; } static int ext3_mkdir(struct inode * dir, struct dentry * dentry, int mode) { handle_t *handle; struct inode * inode; struct buffer_head * dir_block; struct ext3_dir_entry_2 * de; int err, retries = 0; if (dir->i_nlink >= EXT3_LINK_MAX) return -EMLINK; retry: handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3 + 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode = ext3_new_inode (handle, dir, S_IFDIR | mode); err = PTR_ERR(inode); if (IS_ERR(inode)) goto out_stop; inode->i_op = &ext3_dir_inode_operations; inode->i_fop = &ext3_dir_operations; inode->i_size = EXT3_I(inode)->i_disksize = inode->i_sb->s_blocksize; dir_block = ext3_bread (handle, inode, 0, 1, &err); if (!dir_block) { inode->i_nlink--; /* is this nlink == 0? */ ext3_mark_inode_dirty(handle, inode); iput (inode); goto out_stop; } BUFFER_TRACE(dir_block, "get_write_access"); ext3_journal_get_write_access(handle, dir_block); de = (struct ext3_dir_entry_2 *) dir_block->b_data; de->inode = cpu_to_le32(inode->i_ino); de->name_len = 1; de->rec_len = cpu_to_le16(EXT3_DIR_REC_LEN(de->name_len)); strcpy (de->name, "."); ext3_set_de_type(dir->i_sb, de, S_IFDIR); de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); de->inode = cpu_to_le32(dir->i_ino); de->rec_len = cpu_to_le16(inode->i_sb->s_blocksize-EXT3_DIR_REC_LEN(1)); de->name_len = 2; strcpy (de->name, ".."); ext3_set_de_type(dir->i_sb, de, S_IFDIR); inode->i_nlink = 2; BUFFER_TRACE(dir_block, "call ext3_journal_dirty_metadata"); ext3_journal_dirty_metadata(handle, dir_block); brelse (dir_block); ext3_mark_inode_dirty(handle, inode); err = ext3_add_entry (handle, dentry, inode); if (err) { inode->i_nlink = 0; ext3_mark_inode_dirty(handle, inode); iput (inode); goto out_stop; } dir->i_nlink++; ext3_update_dx_flag(dir); ext3_mark_inode_dirty(handle, dir); d_instantiate(dentry, inode); out_stop: ext3_journal_stop(handle); if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) goto retry; return err; } /* * routine to check that the specified directory is empty (for rmdir) */ static int empty_dir (struct inode * inode) { unsigned long offset; struct buffer_head * bh; struct ext3_dir_entry_2 * de, * de1; struct super_block * sb; int err = 0; sb = inode->i_sb; if (inode->i_size < EXT3_DIR_REC_LEN(1) + EXT3_DIR_REC_LEN(2) || !(bh = ext3_bread (NULL, inode, 0, 0, &err))) { if (err) ext3_error(inode->i_sb, __FUNCTION__, "error %d reading directory #%lu offset 0", err, inode->i_ino); else ext3_warning(inode->i_sb, __FUNCTION__, "bad directory (dir #%lu) - no data block", inode->i_ino); return 1; } de = (struct ext3_dir_entry_2 *) bh->b_data; de1 = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); if (le32_to_cpu(de->inode) != inode->i_ino || !le32_to_cpu(de1->inode) || strcmp (".", de->name) || strcmp ("..", de1->name)) { ext3_warning (inode->i_sb, "empty_dir", "bad directory (dir #%lu) - no `.' or `..'", inode->i_ino); brelse (bh); return 1; } offset = le16_to_cpu(de->rec_len) + le16_to_cpu(de1->rec_len); de = (struct ext3_dir_entry_2 *) ((char *) de1 + le16_to_cpu(de1->rec_len)); while (offset < inode->i_size ) { if (!bh || (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) { err = 0; brelse (bh); bh = ext3_bread (NULL, inode, offset >> EXT3_BLOCK_SIZE_BITS(sb), 0, &err); if (!bh) { if (err) ext3_error(sb, __FUNCTION__, "error %d reading directory" " #%lu offset %lu", err, inode->i_ino, offset); offset += sb->s_blocksize; continue; } de = (struct ext3_dir_entry_2 *) bh->b_data; } if (!ext3_check_dir_entry("empty_dir", inode, de, bh, offset)) { de = (struct ext3_dir_entry_2 *)(bh->b_data + sb->s_blocksize); offset = (offset | (sb->s_blocksize - 1)) + 1; continue; } if (le32_to_cpu(de->inode)) { brelse (bh); return 0; } offset += le16_to_cpu(de->rec_len); de = (struct ext3_dir_entry_2 *) ((char *) de + le16_to_cpu(de->rec_len)); } brelse (bh); return 1; } /* ext3_orphan_add() links an unlinked or truncated inode into a list of * such inodes, starting at the superblock, in case we crash before the * file is closed/deleted, or in case the inode truncate spans multiple * transactions and the last transaction is not recovered after a crash. * * At filesystem recovery time, we walk this list deleting unlinked * inodes and truncating linked inodes in ext3_orphan_cleanup(). */ int ext3_orphan_add(handle_t *handle, struct inode *inode) { struct super_block *sb = inode->i_sb; struct ext3_iloc iloc; int err = 0, rc; lock_super(sb); if (!list_empty(&EXT3_I(inode)->i_orphan)) goto out_unlock; /* Orphan handling is only valid for files with data blocks * being truncated, or files being unlinked. */ /* @@@ FIXME: Observation from aviro: * I think I can trigger J_ASSERT in ext3_orphan_add(). We block * here (on lock_super()), so race with ext3_link() which might bump * ->i_nlink. For, say it, character device. Not a regular file, * not a directory, not a symlink and ->i_nlink > 0. */ J_ASSERT ((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); BUFFER_TRACE(EXT3_SB(sb)->s_sbh, "get_write_access"); err = ext3_journal_get_write_access(handle, EXT3_SB(sb)->s_sbh); if (err) goto out_unlock; err = ext3_reserve_inode_write(handle, inode, &iloc); if (err) goto out_unlock; /* Insert this inode at the head of the on-disk orphan list... */ NEXT_ORPHAN(inode) = le32_to_cpu(EXT3_SB(sb)->s_es->s_last_orphan); EXT3_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); err = ext3_journal_dirty_metadata(handle, EXT3_SB(sb)->s_sbh); rc = ext3_mark_iloc_dirty(handle, inode, &iloc); if (!err) err = rc; /* Only add to the head of the in-memory list if all the * previous operations succeeded. If the orphan_add is going to * fail (possibly taking the journal offline), we can't risk * leaving the inode on the orphan list: stray orphan-list * entries can cause panics at unmount time. * * This is safe: on error we're going to ignore the orphan list * anyway on the next recovery. */ if (!err) list_add(&EXT3_I(inode)->i_orphan, &EXT3_SB(sb)->s_orphan); jbd_debug(4, "superblock will point to %ld\n", inode->i_ino); jbd_debug(4, "orphan inode %ld will point to %d\n", inode->i_ino, NEXT_ORPHAN(inode)); out_unlock: unlock_super(sb); ext3_std_error(inode->i_sb, err); return err; } /* * ext3_orphan_del() removes an unlinked or truncated inode from the list * of such inodes stored on disk, because it is finally being cleaned up. */ int ext3_orphan_del(handle_t *handle, struct inode *inode) { struct list_head *prev; struct ext3_inode_info *ei = EXT3_I(inode); struct ext3_sb_info *sbi; unsigned long ino_next; struct ext3_iloc iloc; int err = 0; lock_super(inode->i_sb); if (list_empty(&ei->i_orphan)) { unlock_super(inode->i_sb); return 0; } ino_next = NEXT_ORPHAN(inode); prev = ei->i_orphan.prev; sbi = EXT3_SB(inode->i_sb); jbd_debug(4, "remove inode %lu from orphan list\n", inode->i_ino); list_del_init(&ei->i_orphan); /* If we're on an error path, we may not have a valid * transaction handle with which to update the orphan list on * disk, but we still need to remove the inode from the linked * list in memory. */ if (!handle) goto out; err = ext3_reserve_inode_write(handle, inode, &iloc); if (err) goto out_err; if (prev == &sbi->s_orphan) { jbd_debug(4, "superblock will point to %lu\n", ino_next); BUFFER_TRACE(sbi->s_sbh, "get_write_access"); err = ext3_journal_get_write_access(handle, sbi->s_sbh); if (err) goto out_brelse; sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); err = ext3_journal_dirty_metadata(handle, sbi->s_sbh); } else { struct ext3_iloc iloc2; struct inode *i_prev = &list_entry(prev, struct ext3_inode_info, i_orphan)->vfs_inode; jbd_debug(4, "orphan inode %lu will point to %lu\n", i_prev->i_ino, ino_next); err = ext3_reserve_inode_write(handle, i_prev, &iloc2); if (err) goto out_brelse; NEXT_ORPHAN(i_prev) = ino_next; err = ext3_mark_iloc_dirty(handle, i_prev, &iloc2); } if (err) goto out_brelse; NEXT_ORPHAN(inode) = 0; err = ext3_mark_iloc_dirty(handle, inode, &iloc); out_err: ext3_std_error(inode->i_sb, err); out: unlock_super(inode->i_sb); return err; out_brelse: brelse(iloc.bh); goto out_err; } static int ext3_rmdir (struct inode * dir, struct dentry *dentry) { int retval; struct inode * inode; struct buffer_head * bh; struct ext3_dir_entry_2 * de; handle_t *handle; /* Initialize quotas before so that eventual writes go in * separate transaction */ DQUOT_INIT(dentry->d_inode); handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); retval = -ENOENT; bh = ext3_find_entry (dentry, &de); if (!bh) goto end_rmdir; if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode = dentry->d_inode; retval = -EIO; if (le32_to_cpu(de->inode) != inode->i_ino) goto end_rmdir; retval = -ENOTEMPTY; if (!empty_dir (inode)) goto end_rmdir; retval = ext3_delete_entry(handle, dir, de, bh); if (retval) goto end_rmdir; if (inode->i_nlink != 2) ext3_warning (inode->i_sb, "ext3_rmdir", "empty directory has nlink!=2 (%d)", inode->i_nlink); inode->i_version++; inode->i_nlink = 0; /* There's no need to set i_disksize: the fact that i_nlink is * zero will ensure that the right thing happens during any * recovery. */ inode->i_size = 0; ext3_orphan_add(handle, inode); inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; ext3_mark_inode_dirty(handle, inode); dir->i_nlink--; ext3_update_dx_flag(dir); ext3_mark_inode_dirty(handle, dir); end_rmdir: ext3_journal_stop(handle); brelse (bh); return retval; } static int ext3_unlink(struct inode * dir, struct dentry *dentry) { int retval; struct inode * inode; struct buffer_head * bh; struct ext3_dir_entry_2 * de; handle_t *handle; /* Initialize quotas before so that eventual writes go * in separate transaction */ DQUOT_INIT(dentry->d_inode); handle = ext3_journal_start(dir, EXT3_DELETE_TRANS_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; retval = -ENOENT; bh = ext3_find_entry (dentry, &de); if (!bh) goto end_unlink; inode = dentry->d_inode; retval = -EIO; if (le32_to_cpu(de->inode) != inode->i_ino) goto end_unlink; if (!inode->i_nlink) { ext3_warning (inode->i_sb, "ext3_unlink", "Deleting nonexistent file (%lu), %d", inode->i_ino, inode->i_nlink); inode->i_nlink = 1; } retval = ext3_delete_entry(handle, dir, de, bh); if (retval) goto end_unlink; dir->i_ctime = dir->i_mtime = CURRENT_TIME_SEC; ext3_update_dx_flag(dir); ext3_mark_inode_dirty(handle, dir); inode->i_nlink--; if (!inode->i_nlink) ext3_orphan_add(handle, inode); inode->i_ctime = dir->i_ctime; ext3_mark_inode_dirty(handle, inode); retval = 0; end_unlink: ext3_journal_stop(handle); brelse (bh); return retval; } static int ext3_symlink (struct inode * dir, struct dentry *dentry, const char * symname) { handle_t *handle; struct inode * inode; int l, err, retries = 0; l = strlen(symname)+1; if (l > dir->i_sb->s_blocksize) return -ENAMETOOLONG; retry: handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 5 + 2*EXT3_QUOTA_INIT_BLOCKS(dir->i_sb)); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode = ext3_new_inode (handle, dir, S_IFLNK|S_IRWXUGO); err = PTR_ERR(inode); if (IS_ERR(inode)) goto out_stop; if (l > sizeof (EXT3_I(inode)->i_data)) { inode->i_op = &ext3_symlink_inode_operations; ext3_set_aops(inode); /* * page_symlink() calls into ext3_prepare/commit_write. * We have a transaction open. All is sweetness. It also sets * i_size in generic_commit_write(). */ err = __page_symlink(inode, symname, l, mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS); if (err) { ext3_dec_count(handle, inode); ext3_mark_inode_dirty(handle, inode); iput (inode); goto out_stop; } } else { inode->i_op = &ext3_fast_symlink_inode_operations; memcpy((char*)&EXT3_I(inode)->i_data,symname,l); inode->i_size = l-1; } EXT3_I(inode)->i_disksize = inode->i_size; err = ext3_add_nondir(handle, dentry, inode); out_stop: ext3_journal_stop(handle); if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) goto retry; return err; } static int ext3_link (struct dentry * old_dentry, struct inode * dir, struct dentry *dentry) { handle_t *handle; struct inode *inode = old_dentry->d_inode; int err, retries = 0; if (inode->i_nlink >= EXT3_LINK_MAX) return -EMLINK; retry: handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS(dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(dir)) handle->h_sync = 1; inode->i_ctime = CURRENT_TIME_SEC; ext3_inc_count(handle, inode); atomic_inc(&inode->i_count); err = ext3_add_nondir(handle, dentry, inode); ext3_journal_stop(handle); if (err == -ENOSPC && ext3_should_retry_alloc(dir->i_sb, &retries)) goto retry; return err; } #define PARENT_INO(buffer) \ ((struct ext3_dir_entry_2 *) ((char *) buffer + \ le16_to_cpu(((struct ext3_dir_entry_2 *) buffer)->rec_len)))->inode /* * Anybody can rename anything with this: the permission checks are left to the * higher-level routines. */ static int ext3_rename (struct inode * old_dir, struct dentry *old_dentry, struct inode * new_dir,struct dentry *new_dentry) { handle_t *handle; struct inode * old_inode, * new_inode; struct buffer_head * old_bh, * new_bh, * dir_bh; struct ext3_dir_entry_2 * old_de, * new_de; int retval; old_bh = new_bh = dir_bh = NULL; /* Initialize quotas before so that eventual writes go * in separate transaction */ if (new_dentry->d_inode) DQUOT_INIT(new_dentry->d_inode); handle = ext3_journal_start(old_dir, 2 * EXT3_DATA_TRANS_BLOCKS(old_dir->i_sb) + EXT3_INDEX_EXTRA_TRANS_BLOCKS + 2); if (IS_ERR(handle)) return PTR_ERR(handle); if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) handle->h_sync = 1; old_bh = ext3_find_entry (old_dentry, &old_de); /* * Check for inode number is _not_ due to possible IO errors. * We might rmdir the source, keep it as pwd of some process * and merrily kill the link to whatever was created under the * same name. Goodbye sticky bit ;-< */ old_inode = old_dentry->d_inode; retval = -ENOENT; if (!old_bh || le32_to_cpu(old_de->inode) != old_inode->i_ino) goto end_rename; new_inode = new_dentry->d_inode; new_bh = ext3_find_entry (new_dentry, &new_de); if (new_bh) { if (!new_inode) { brelse (new_bh); new_bh = NULL; } } if (S_ISDIR(old_inode->i_mode)) { if (new_inode) { retval = -ENOTEMPTY; if (!empty_dir (new_inode)) goto end_rename; } retval = -EIO; dir_bh = ext3_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) goto end_rename; retval = -EMLINK; if (!new_inode && new_dir!=old_dir && new_dir->i_nlink >= EXT3_LINK_MAX) goto end_rename; } if (!new_bh) { retval = ext3_add_entry (handle, new_dentry, old_inode); if (retval) goto end_rename; } else { BUFFER_TRACE(new_bh, "get write access"); ext3_journal_get_write_access(handle, new_bh); new_de->inode = cpu_to_le32(old_inode->i_ino); if (EXT3_HAS_INCOMPAT_FEATURE(new_dir->i_sb, EXT3_FEATURE_INCOMPAT_FILETYPE)) new_de->file_type = old_de->file_type; new_dir->i_version++; BUFFER_TRACE(new_bh, "call ext3_journal_dirty_metadata"); ext3_journal_dirty_metadata(handle, new_bh); brelse(new_bh); new_bh = NULL; } /* * Like most other Unix systems, set the ctime for inodes on a * rename. */ old_inode->i_ctime = CURRENT_TIME_SEC; ext3_mark_inode_dirty(handle, old_inode); /* * ok, that's it */ if (le32_to_cpu(old_de->inode) != old_inode->i_ino || old_de->name_len != old_dentry->d_name.len || strncmp(old_de->name, old_dentry->d_name.name, old_de->name_len) || (retval = ext3_delete_entry(handle, old_dir, old_de, old_bh)) == -ENOENT) { /* old_de could have moved from under us during htree split, so * make sure that we are deleting the right entry. We might * also be pointing to a stale entry in the unused part of * old_bh so just checking inum and the name isn't enough. */ struct buffer_head *old_bh2; struct ext3_dir_entry_2 *old_de2; old_bh2 = ext3_find_entry(old_dentry, &old_de2); if (old_bh2) { retval = ext3_delete_entry(handle, old_dir, old_de2, old_bh2); brelse(old_bh2); } } if (retval) { ext3_warning(old_dir->i_sb, "ext3_rename", "Deleting old file (%lu), %d, error=%d", old_dir->i_ino, old_dir->i_nlink, retval); } if (new_inode) { new_inode->i_nlink--; new_inode->i_ctime = CURRENT_TIME_SEC; } old_dir->i_ctime = old_dir->i_mtime = CURRENT_TIME_SEC; ext3_update_dx_flag(old_dir); if (dir_bh) { BUFFER_TRACE(dir_bh, "get_write_access"); ext3_journal_get_write_access(handle, dir_bh); PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino); BUFFER_TRACE(dir_bh, "call ext3_journal_dirty_metadata"); ext3_journal_dirty_metadata(handle, dir_bh); old_dir->i_nlink--; if (new_inode) { new_inode->i_nlink--; } else { new_dir->i_nlink++; ext3_update_dx_flag(new_dir); ext3_mark_inode_dirty(handle, new_dir); } } ext3_mark_inode_dirty(handle, old_dir); if (new_inode) { ext3_mark_inode_dirty(handle, new_inode); if (!new_inode->i_nlink) ext3_orphan_add(handle, new_inode); } retval = 0; end_rename: brelse (dir_bh); brelse (old_bh); brelse (new_bh); ext3_journal_stop(handle); return retval; } /* * directories can handle most operations... */ struct inode_operations ext3_dir_inode_operations = { .create = ext3_create, .lookup = ext3_lookup, .link = ext3_link, .unlink = ext3_unlink, .symlink = ext3_symlink, .mkdir = ext3_mkdir, .rmdir = ext3_rmdir, .mknod = ext3_mknod, .rename = ext3_rename, .setattr = ext3_setattr, #ifdef CONFIG_EXT3_FS_XATTR .setxattr = generic_setxattr, .getxattr = generic_getxattr, .listxattr = ext3_listxattr, .removexattr = generic_removexattr, #endif .permission = ext3_permission, }; struct inode_operations ext3_special_inode_operations = { .setattr = ext3_setattr, #ifdef CONFIG_EXT3_FS_XATTR .setxattr = generic_setxattr, .getxattr = generic_getxattr, .listxattr = ext3_listxattr, .removexattr = generic_removexattr, #endif .permission = ext3_permission, };