diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/ext4/namei.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/ext4/namei.c | 2607 |
1 files changed, 0 insertions, 2607 deletions
diff --git a/ANDROID_3.4.5/fs/ext4/namei.c b/ANDROID_3.4.5/fs/ext4/namei.c deleted file mode 100644 index 0a94cbbe..00000000 --- a/ANDROID_3.4.5/fs/ext4/namei.c +++ /dev/null @@ -1,2607 +0,0 @@ -/* - * linux/fs/ext4/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 <linux/fs.h> -#include <linux/pagemap.h> -#include <linux/jbd2.h> -#include <linux/time.h> -#include <linux/fcntl.h> -#include <linux/stat.h> -#include <linux/string.h> -#include <linux/quotaops.h> -#include <linux/buffer_head.h> -#include <linux/bio.h> -#include "ext4.h" -#include "ext4_jbd2.h" - -#include "xattr.h" -#include "acl.h" - -#include <trace/events/ext4.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 *ext4_append(handle_t *handle, - struct inode *inode, - ext4_lblk_t *block, int *err) -{ - struct buffer_head *bh; - - *block = inode->i_size >> inode->i_sb->s_blocksize_bits; - - bh = ext4_bread(handle, inode, *block, 1, err); - if (bh) { - inode->i_size += inode->i_sb->s_blocksize; - EXT4_I(inode)->i_disksize = inode->i_size; - *err = ext4_journal_get_write_access(handle, bh); - if (*err) { - brelse(bh); - bh = NULL; - } - } - return bh; -} - -#ifndef assert -#define assert(test) J_ASSERT(test) -#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; - u16 offs; - u16 size; -}; - -static inline ext4_lblk_t dx_get_block(struct dx_entry *entry); -static void dx_set_block(struct dx_entry *entry, ext4_lblk_t 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(const struct qstr *d_name, - 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 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, 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); -static int ext4_htree_next_block(struct inode *dir, __u32 hash, - struct dx_frame *frame, - struct dx_frame *frames, - __u32 *start_hash); -static struct buffer_head * ext4_dx_find_entry(struct inode *dir, - const struct qstr *d_name, - struct ext4_dir_entry_2 **res_dir, - int *err); -static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry, - struct inode *inode); - -/* - * 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, unsigned long blocksize) -{ - return (struct ext4_dir_entry_2 *)((char *)p + - ext4_rec_len_from_disk(p->rec_len, blocksize)); -} - -/* - * Future: use high four bits of block for coalesce-on-delete flags - * Mask them off for now. - */ - -static inline ext4_lblk_t dx_get_block(struct dx_entry *entry) -{ - return le32_to_cpu(entry->block) & 0x00ffffff; -} - -static inline void dx_set_block(struct dx_entry *entry, ext4_lblk_t 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 - EXT4_DIR_REC_LEN(1) - - EXT4_DIR_REC_LEN(2) - infosize; - return entry_space / sizeof(struct dx_entry); -} - -static inline unsigned dx_node_limit(struct inode *dir) -{ - unsigned entry_space = dir->i_sb->s_blocksize - EXT4_DIR_REC_LEN(0); - return 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(KERN_DEBUG "%s index ", label); - for (i = 0; i < n; i++) { - printk("%x->%lu ", i ? dx_get_hash(entries + i) : - 0, (unsigned long)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 ext4_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++); - ext4fs_dirhash(de->name, de->name_len, &h); - printk(":%x.%u ", h.hash, - (unsigned) ((char *) de - base)); - } - space += EXT4_DIR_REC_LEN(de->name_len); - names++; - } - de = ext4_next_entry(de, size); - } - 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++) - { - ext4_lblk_t block = dx_get_block(entries); - ext4_lblk_t 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 = ext4_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 ext4_dir_entry_2 *) bh->b_data, blocksize, 0); - names += stats.names; - space += stats.space; - bcount += stats.bcount; - brelse(bh); - } - if (bcount) - printk(KERN_DEBUG "%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(const struct qstr *d_name, 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 (!(bh = ext4_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) { - ext4_warning(dir->i_sb, "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; - if (hinfo->hash_version <= DX_HASH_TEA) - hinfo->hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; - hinfo->seed = EXT4_SB(dir->i_sb)->s_hash_seed; - if (d_name) - ext4fs_dirhash(d_name->name, d_name->len, hinfo); - hash = hinfo->hash; - - if (root->info.unused_flags & 1) { - ext4_warning(dir->i_sb, "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) { - ext4_warning(dir->i_sb, "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); - - if (dx_get_limit(entries) != dx_root_limit(dir, - root->info.info_length)) { - ext4_warning(dir->i_sb, "dx entry: limit != root limit"); - brelse(bh); - *err = ERR_BAD_DX_DIR; - goto fail; - } - - dxtrace(printk("Look up %x", hash)); - while (1) - { - count = dx_get_count(entries); - if (!count || count > dx_get_limit(entries)) { - ext4_warning(dir->i_sb, - "dx entry: no count or count > limit"); - brelse(bh); - *err = ERR_BAD_DX_DIR; - goto fail2; - } - - 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 = ext4_bread (NULL,dir, dx_get_block(at), 0, err))) - goto fail2; - at = entries = ((struct dx_node *) bh->b_data)->entries; - if (dx_get_limit(entries) != dx_node_limit (dir)) { - ext4_warning(dir->i_sb, - "dx entry: limit != node limit"); - brelse(bh); - *err = ERR_BAD_DX_DIR; - goto fail2; - } - frame++; - frame->bh = NULL; - } -fail2: - while (frame >= frame_in) { - brelse(frame->bh); - frame--; - } -fail: - if (*err == ERR_BAD_DX_DIR) - ext4_warning(dir->i_sb, - "Corrupt dir inode %lu, running e2fsck is " - "recommended.", dir->i_ino); - 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 ext4_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 = ext4_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; -} - - -/* - * 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, ext4_lblk_t block, - struct dx_hash_info *hinfo, - __u32 start_hash, __u32 start_minor_hash) -{ - struct buffer_head *bh; - struct ext4_dir_entry_2 *de, *top; - int err, count = 0; - - dxtrace(printk(KERN_INFO "In htree dirblock_to_tree: block %lu\n", - (unsigned long)block)); - if (!(bh = ext4_bread (NULL, dir, block, 0, &err))) - return err; - - de = (struct ext4_dir_entry_2 *) bh->b_data; - 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, dir->i_sb->s_blocksize)) { - if (ext4_check_dir_entry(dir, NULL, de, bh, - (block<<EXT4_BLOCK_SIZE_BITS(dir->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; - } - ext4fs_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 = ext4_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 ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash, - __u32 start_minor_hash, __u32 *next_hash) -{ - struct dx_hash_info hinfo; - struct ext4_dir_entry_2 *de; - struct dx_frame frames[2], *frame; - struct inode *dir; - ext4_lblk_t block; - int count = 0; - int ret, err; - __u32 hashval; - - dxtrace(printk(KERN_DEBUG "In htree_fill_tree, start hash: %x:%x\n", - start_hash, start_minor_hash)); - dir = dir_file->f_path.dentry->d_inode; - if (!(ext4_test_inode_flag(dir, EXT4_INODE_INDEX))) { - hinfo.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version; - if (hinfo.hash_version <= DX_HASH_TEA) - hinfo.hash_version += - EXT4_SB(dir->i_sb)->s_hash_unsigned; - hinfo.seed = EXT4_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, &hinfo, frames, &err); - if (!frame) - return err; - - /* Add '.' and '..' from the htree header */ - if (!start_hash && !start_minor_hash) { - de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data; - if ((err = ext4_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 ext4_dir_entry_2 *) frames[0].bh->b_data; - 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++; - } - - 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 = ext4_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(KERN_DEBUG "Fill tree: returned %d entries, " - "next hash: %x\n", count, *next_hash)); - return count; -errout: - dx_release(frames); - return (err); -} - - -/* - * Directory block splitting, compacting - */ - -/* - * Create map of hash values, offsets, and sizes, stored at end of block. - * Returns number of entries mapped. - */ -static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize, - 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 + blocksize) { - if (de->name_len && de->inode) { - ext4fs_dirhash(de->name, de->name_len, &h); - map_tail--; - map_tail->hash = h.hash; - map_tail->offs = ((char *) de - base)>>2; - map_tail->size = le16_to_cpu(de->rec_len); - count++; - cond_resched(); - } - /* XXX: do we need to check rec_len == 0 case? -Chris */ - de = ext4_next_entry(de, blocksize); - } - return count; -} - -/* Sort map by hash value */ -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, ext4_lblk_t 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); -} - -static void ext4_update_dx_flag(struct inode *inode) -{ - if (!EXT4_HAS_COMPAT_FEATURE(inode->i_sb, - EXT4_FEATURE_COMPAT_DIR_INDEX)) - ext4_clear_inode_flag(inode, EXT4_INODE_INDEX); -} - -/* - * NOTE! unlike strncmp, ext4_match returns 1 for success, 0 for failure. - * - * `len <= EXT4_NAME_LEN' is guaranteed by caller. - * `de != NULL' is guaranteed by caller. - */ -static inline int ext4_match (int len, const char * const name, - struct ext4_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, - const struct qstr *d_name, - unsigned int offset, - struct ext4_dir_entry_2 ** res_dir) -{ - struct ext4_dir_entry_2 * de; - char * dlimit; - int de_len; - const char *name = d_name->name; - int namelen = d_name->len; - - de = (struct ext4_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 && - ext4_match (namelen, name, de)) { - /* found a match - just to be sure, do a full check */ - if (ext4_check_dir_entry(dir, NULL, de, bh, offset)) - return -1; - *res_dir = de; - return 1; - } - /* prevent looping on a bad block */ - de_len = ext4_rec_len_from_disk(de->rec_len, - dir->i_sb->s_blocksize); - if (de_len <= 0) - return -1; - offset += de_len; - de = (struct ext4_dir_entry_2 *) ((char *) de + de_len); - } - return 0; -} - - -/* - * ext4_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 * ext4_find_entry (struct inode *dir, - const struct qstr *d_name, - struct ext4_dir_entry_2 ** res_dir) -{ - struct super_block *sb; - struct buffer_head *bh_use[NAMEI_RA_SIZE]; - struct buffer_head *bh, *ret = NULL; - ext4_lblk_t start, block, b; - const u8 *name = d_name->name; - 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; - ext4_lblk_t nblocks; - int i, err; - int namelen; - - *res_dir = NULL; - sb = dir->i_sb; - namelen = d_name->len; - if (namelen > EXT4_NAME_LEN) - return NULL; - if ((namelen <= 2) && (name[0] == '.') && - (name[1] == '.' || name[1] == '\0')) { - /* - * "." or ".." will only be in the first block - * NFS may look up ".."; "." should be handled by the VFS - */ - block = start = 0; - nblocks = 1; - goto restart; - } - if (is_dx(dir)) { - bh = ext4_dx_find_entry(dir, d_name, 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(KERN_DEBUG "ext4_find_entry: dx failed, " - "falling back\n")); - } - nblocks = dir->i_size >> EXT4_BLOCK_SIZE_BITS(sb); - start = EXT4_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 = ext4_getblk(NULL, dir, b++, 0, &err); - bh_use[ra_max] = bh; - if (bh) - ll_rw_block(READ | REQ_META | REQ_PRIO, - 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 */ - EXT4_ERROR_INODE(dir, "reading directory lblock %lu", - (unsigned long) block); - brelse(bh); - goto next; - } - i = search_dirblock(bh, dir, d_name, - block << EXT4_BLOCK_SIZE_BITS(sb), res_dir); - if (i == 1) { - EXT4_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 >> EXT4_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; -} - -static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct qstr *d_name, - struct ext4_dir_entry_2 **res_dir, int *err) -{ - struct super_block * sb = dir->i_sb; - struct dx_hash_info hinfo; - struct dx_frame frames[2], *frame; - struct buffer_head *bh; - ext4_lblk_t block; - int retval; - - if (!(frame = dx_probe(d_name, dir, &hinfo, frames, err))) - return NULL; - do { - block = dx_get_block(frame->at); - if (!(bh = ext4_bread(NULL, dir, block, 0, err))) - goto errout; - - retval = search_dirblock(bh, dir, d_name, - block << EXT4_BLOCK_SIZE_BITS(sb), - res_dir); - if (retval == 1) { /* Success! */ - dx_release(frames); - return bh; - } - brelse(bh); - if (retval == -1) { - *err = ERR_BAD_DX_DIR; - goto errout; - } - - /* Check to see if we should continue to search */ - retval = ext4_htree_next_block(dir, hinfo.hash, frame, - frames, NULL); - if (retval < 0) { - ext4_warning(sb, - "error reading index page in directory #%lu", - dir->i_ino); - *err = retval; - goto errout; - } - } while (retval == 1); - - *err = -ENOENT; -errout: - dxtrace(printk(KERN_DEBUG "%s not found\n", d_name->name)); - dx_release (frames); - return NULL; -} - -static struct dentry *ext4_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) -{ - struct inode *inode; - struct ext4_dir_entry_2 *de; - struct buffer_head *bh; - - if (dentry->d_name.len > EXT4_NAME_LEN) - return ERR_PTR(-ENAMETOOLONG); - - bh = ext4_find_entry(dir, &dentry->d_name, &de); - inode = NULL; - if (bh) { - __u32 ino = le32_to_cpu(de->inode); - brelse(bh); - if (!ext4_valid_inum(dir->i_sb, ino)) { - EXT4_ERROR_INODE(dir, "bad inode number: %u", ino); - return ERR_PTR(-EIO); - } - if (unlikely(ino == dir->i_ino)) { - EXT4_ERROR_INODE(dir, "'%.*s' linked to parent dir", - dentry->d_name.len, - dentry->d_name.name); - return ERR_PTR(-EIO); - } - inode = ext4_iget(dir->i_sb, ino); - if (inode == ERR_PTR(-ESTALE)) { - EXT4_ERROR_INODE(dir, - "deleted inode referenced: %u", - ino); - return ERR_PTR(-EIO); - } - } - return d_splice_alias(inode, dentry); -} - - -struct dentry *ext4_get_parent(struct dentry *child) -{ - __u32 ino; - static const struct qstr dotdot = { - .name = "..", - .len = 2, - }; - struct ext4_dir_entry_2 * de; - struct buffer_head *bh; - - bh = ext4_find_entry(child->d_inode, &dotdot, &de); - if (!bh) - return ERR_PTR(-ENOENT); - ino = le32_to_cpu(de->inode); - brelse(bh); - - if (!ext4_valid_inum(child->d_inode->i_sb, ino)) { - EXT4_ERROR_INODE(child->d_inode, - "bad parent inode number: %u", ino); - return ERR_PTR(-EIO); - } - - return d_obtain_alias(ext4_iget(child->d_inode->i_sb, ino)); -} - -#define S_SHIFT 12 -static unsigned char ext4_type_by_mode[S_IFMT >> S_SHIFT] = { - [S_IFREG >> S_SHIFT] = EXT4_FT_REG_FILE, - [S_IFDIR >> S_SHIFT] = EXT4_FT_DIR, - [S_IFCHR >> S_SHIFT] = EXT4_FT_CHRDEV, - [S_IFBLK >> S_SHIFT] = EXT4_FT_BLKDEV, - [S_IFIFO >> S_SHIFT] = EXT4_FT_FIFO, - [S_IFSOCK >> S_SHIFT] = EXT4_FT_SOCK, - [S_IFLNK >> S_SHIFT] = EXT4_FT_SYMLINK, -}; - -static inline void ext4_set_de_type(struct super_block *sb, - struct ext4_dir_entry_2 *de, - umode_t mode) { - if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FILETYPE)) - de->file_type = ext4_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; -} - -/* - * Move count entries from end of map between two memory locations. - * 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, - unsigned blocksize) -{ - unsigned rec_len = 0; - - while (count--) { - struct ext4_dir_entry_2 *de = (struct ext4_dir_entry_2 *) - (from + (map->offs<<2)); - 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, blocksize); - de->inode = 0; - map++; - to += rec_len; - } - return (struct ext4_dir_entry_2 *) (to - rec_len); -} - -/* - * Compact each dir entry in the range to the minimal rec_len. - * Returns pointer to last entry in range. - */ -static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize) -{ - struct ext4_dir_entry_2 *next, *to, *prev, *de = (struct ext4_dir_entry_2 *) base; - unsigned rec_len = 0; - - prev = to = de; - while ((char*)de < base + blocksize) { - 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, blocksize); - prev = to; - to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len); - } - de = next; - } - return prev; -} - -/* - * Split a full leaf block to make room for a new dir entry. - * Allocate a new block, and move entries so that they are approx. equally full. - * Returns pointer to de in block into which the new entry will be inserted. - */ -static struct ext4_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; - ext4_lblk_t newblock; - u32 hash2; - struct dx_map_entry *map; - char *data1 = (*bh)->b_data, *data2; - unsigned split, move, size; - struct ext4_dir_entry_2 *de = NULL, *de2; - int err = 0, i; - - bh2 = ext4_append (handle, dir, &newblock, &err); - if (!(bh2)) { - brelse(*bh); - *bh = NULL; - goto errout; - } - - BUFFER_TRACE(*bh, "get_write_access"); - err = ext4_journal_get_write_access(handle, *bh); - if (err) - goto journal_error; - - BUFFER_TRACE(frame->bh, "get_write_access"); - err = ext4_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 ext4_dir_entry_2 *) data1, - blocksize, hinfo, map); - map -= count; - dx_sort_map(map, count); - /* Split the existing block in the middle, size-wise */ - size = 0; - move = 0; - for (i = count-1; i >= 0; i--) { - /* is more than half of this entry in 2nd half of the block? */ - if (size + map[i].size/2 > blocksize/2) - break; - size += map[i].size; - move++; - } - /* map index at which we will split */ - split = count - move; - hash2 = map[split].hash; - continued = hash2 == map[split - 1].hash; - dxtrace(printk(KERN_INFO "Split block %lu at %x, %i/%i\n", - (unsigned long)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, blocksize); - de = dx_pack_dirents(data1, blocksize); - 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)); - - /* Which block gets the new entry? */ - if (hinfo->hash >= hash2) - { - swap(*bh, bh2); - de = de2; - } - dx_insert_block(frame, hash2 + continued, newblock); - err = ext4_handle_dirty_metadata(handle, dir, bh2); - if (err) - goto journal_error; - err = ext4_handle_dirty_metadata(handle, dir, frame->bh); - if (err) - goto journal_error; - brelse(bh2); - dxtrace(dx_show_index("frame", frame->entries)); - return de; - -journal_error: - brelse(*bh); - brelse(bh2); - *bh = NULL; - ext4_std_error(dir->i_sb, err); -errout: - *error = err; - return NULL; -} - -/* - * 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. - */ -static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry, - struct inode *inode, struct ext4_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 int offset = 0; - unsigned int blocksize = dir->i_sb->s_blocksize; - unsigned short reclen; - int nlen, rlen, err; - char *top; - - reclen = EXT4_DIR_REC_LEN(namelen); - if (!de) { - de = (struct ext4_dir_entry_2 *)bh->b_data; - top = bh->b_data + blocksize - reclen; - while ((char *) de <= top) { - if (ext4_check_dir_entry(dir, NULL, de, bh, offset)) - return -EIO; - if (ext4_match(namelen, name, de)) - return -EEXIST; - nlen = EXT4_DIR_REC_LEN(de->name_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); - offset += rlen; - } - if ((char *) de > top) - return -ENOSPC; - } - BUFFER_TRACE(bh, "get_write_access"); - err = ext4_journal_get_write_access(handle, bh); - if (err) { - ext4_std_error(dir->i_sb, err); - return err; - } - - /* 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, 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, blocksize); - de->rec_len = ext4_rec_len_to_disk(nlen, blocksize); - de = de1; - } - de->file_type = EXT4_FT_UNKNOWN; - if (inode) { - de->inode = cpu_to_le32(inode->i_ino); - ext4_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 - * ext4_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 = ext4_current_time(dir); - ext4_update_dx_flag(dir); - dir->i_version++; - ext4_mark_inode_dirty(handle, dir); - BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); - err = ext4_handle_dirty_metadata(handle, dir, bh); - if (err) - ext4_std_error(dir->i_sb, err); - return 0; -} - -/* - * 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 ext4_dir_entry_2 *de, *de2; - char *data1, *top; - unsigned len; - int retval; - unsigned blocksize; - struct dx_hash_info hinfo; - ext4_lblk_t block; - struct fake_dirent *fde; - - blocksize = dir->i_sb->s_blocksize; - dxtrace(printk(KERN_DEBUG "Creating index: inode %lu\n", dir->i_ino)); - retval = ext4_journal_get_write_access(handle, bh); - if (retval) { - ext4_std_error(dir->i_sb, retval); - brelse(bh); - return retval; - } - root = (struct dx_root *) bh->b_data; - - /* 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, blocksize)); - if ((char *) de >= (((char *) root) + blocksize)) { - EXT4_ERROR_INODE(dir, "invalid rec_len for '..'"); - brelse(bh); - return -EIO; - } - len = ((char *) root) + blocksize - (char *) de; - - /* Allocate new block for the 0th block's dirents */ - bh2 = ext4_append(handle, dir, &block, &retval); - if (!(bh2)) { - brelse(bh); - return retval; - } - ext4_set_inode_flag(dir, EXT4_INODE_INDEX); - data1 = bh2->b_data; - - memcpy (data1, de, len); - de = (struct ext4_dir_entry_2 *) data1; - top = data1 + len; - while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top) - de = de2; - 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), - 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; - 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; - if (hinfo.hash_version <= DX_HASH_TEA) - hinfo.hash_version += EXT4_SB(dir->i_sb)->s_hash_unsigned; - hinfo.seed = EXT4_SB(dir->i_sb)->s_hash_seed; - ext4fs_dirhash(name, namelen, &hinfo); - frame = frames; - frame->entries = entries; - frame->at = entries; - frame->bh = bh; - bh = bh2; - - ext4_handle_dirty_metadata(handle, dir, frame->bh); - ext4_handle_dirty_metadata(handle, dir, bh); - - de = do_split(handle,dir, &bh, frame, &hinfo, &retval); - if (!de) { - /* - * Even if the block split failed, we have to properly write - * out all the changes we did so far. Otherwise we can end up - * with corrupted filesystem. - */ - ext4_mark_inode_dirty(handle, dir); - dx_release(frames); - return retval; - } - dx_release(frames); - - retval = add_dirent_to_buf(handle, dentry, inode, de, bh); - brelse(bh); - return retval; -} - -/* - * ext4_add_entry() - * - * adds a file entry to the specified directory, using the same - * semantics as ext4_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 ext4_add_entry(handle_t *handle, struct dentry *dentry, - struct inode *inode) -{ - struct inode *dir = dentry->d_parent->d_inode; - struct buffer_head *bh; - struct ext4_dir_entry_2 *de; - struct super_block *sb; - int retval; - int dx_fallback=0; - unsigned blocksize; - ext4_lblk_t block, blocks; - - sb = dir->i_sb; - blocksize = sb->s_blocksize; - if (!dentry->d_name.len) - return -EINVAL; - if (is_dx(dir)) { - retval = ext4_dx_add_entry(handle, dentry, inode); - if (!retval || (retval != ERR_BAD_DX_DIR)) - return retval; - ext4_clear_inode_flag(dir, EXT4_INODE_INDEX); - dx_fallback++; - ext4_mark_inode_dirty(handle, dir); - } - blocks = dir->i_size >> sb->s_blocksize_bits; - for (block = 0; block < blocks; block++) { - bh = ext4_bread(handle, dir, block, 0, &retval); - if(!bh) - return retval; - retval = add_dirent_to_buf(handle, dentry, inode, NULL, bh); - if (retval != -ENOSPC) { - brelse(bh); - return retval; - } - - if (blocks == 1 && !dx_fallback && - EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_DIR_INDEX)) - return make_indexed_dir(handle, dentry, inode, bh); - brelse(bh); - } - bh = ext4_append(handle, dir, &block, &retval); - if (!bh) - return retval; - de = (struct ext4_dir_entry_2 *) bh->b_data; - de->inode = 0; - de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize); - retval = add_dirent_to_buf(handle, dentry, inode, de, bh); - brelse(bh); - if (retval == 0) - ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); - return retval; -} - -/* - * Returns 0 for success, or a negative error value - */ -static int ext4_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 ext4_dir_entry_2 *de; - int err; - - frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err); - if (!frame) - return err; - entries = frame->entries; - at = frame->at; - - if (!(bh = ext4_bread(handle,dir, dx_get_block(frame->at), 0, &err))) - goto cleanup; - - BUFFER_TRACE(bh, "get_write_access"); - err = ext4_journal_get_write_access(handle, bh); - if (err) - goto journal_error; - - err = add_dirent_to_buf(handle, dentry, inode, NULL, bh); - if (err != -ENOSPC) - goto cleanup; - - /* Block full, should compress but for now just split */ - dxtrace(printk(KERN_DEBUG "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)) { - ext4_lblk_t 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))) { - ext4_warning(sb, "Directory index full!"); - err = -ENOSPC; - goto cleanup; - } - bh2 = ext4_append (handle, dir, &newblock, &err); - if (!(bh2)) - goto cleanup; - node2 = (struct dx_node *)(bh2->b_data); - entries2 = node2->entries; - memset(&node2->fake, 0, sizeof(struct fake_dirent)); - node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize, - sb->s_blocksize); - BUFFER_TRACE(frame->bh, "get_write_access"); - err = ext4_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(KERN_DEBUG "Split index %i/%i\n", - icount1, icount2)); - - BUFFER_TRACE(frame->bh, "get_write_access"); /* index root */ - err = ext4_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 = ext4_handle_dirty_metadata(handle, dir, bh2); - if (err) - goto journal_error; - brelse (bh2); - } else { - dxtrace(printk(KERN_DEBUG - "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 = ext4_journal_get_write_access(handle, - frame->bh); - if (err) - goto journal_error; - } - err = ext4_handle_dirty_metadata(handle, dir, frames[0].bh); - if (err) { - ext4_std_error(inode->i_sb, err); - goto cleanup; - } - } - de = do_split(handle, dir, &bh, frame, &hinfo, &err); - if (!de) - goto cleanup; - err = add_dirent_to_buf(handle, dentry, inode, de, bh); - goto cleanup; - -journal_error: - ext4_std_error(dir->i_sb, err); -cleanup: - if (bh) - brelse(bh); - dx_release(frames); - return err; -} - -/* - * ext4_delete_entry deletes a directory entry by merging it with the - * previous entry - */ -static int ext4_delete_entry(handle_t *handle, - struct inode *dir, - struct ext4_dir_entry_2 *de_del, - struct buffer_head *bh) -{ - struct ext4_dir_entry_2 *de, *pde; - unsigned int blocksize = dir->i_sb->s_blocksize; - int i, err; - - i = 0; - pde = NULL; - de = (struct ext4_dir_entry_2 *) bh->b_data; - while (i < bh->b_size) { - if (ext4_check_dir_entry(dir, NULL, de, bh, i)) - return -EIO; - if (de == de_del) { - BUFFER_TRACE(bh, "get_write_access"); - err = ext4_journal_get_write_access(handle, bh); - if (unlikely(err)) { - ext4_std_error(dir->i_sb, err); - return err; - } - if (pde) - pde->rec_len = ext4_rec_len_to_disk( - 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++; - BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); - err = ext4_handle_dirty_metadata(handle, dir, bh); - if (unlikely(err)) { - ext4_std_error(dir->i_sb, err); - return err; - } - return 0; - } - i += ext4_rec_len_from_disk(de->rec_len, blocksize); - pde = de; - de = ext4_next_entry(de, blocksize); - } - return -ENOENT; -} - -/* - * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2, - * since this indicates that nlinks count was previously 1. - */ -static void ext4_inc_count(handle_t *handle, struct inode *inode) -{ - inc_nlink(inode); - if (is_dx(inode) && inode->i_nlink > 1) { - /* limit is 16-bit i_links_count */ - if (inode->i_nlink >= EXT4_LINK_MAX || inode->i_nlink == 2) { - set_nlink(inode, 1); - EXT4_SET_RO_COMPAT_FEATURE(inode->i_sb, - EXT4_FEATURE_RO_COMPAT_DIR_NLINK); - } - } -} - -/* - * If a directory had nlink == 1, then we should let it be 1. This indicates - * directory has >EXT4_LINK_MAX subdirs. - */ -static void ext4_dec_count(handle_t *handle, struct inode *inode) -{ - if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2) - drop_nlink(inode); -} - - -static int ext4_add_nondir(handle_t *handle, - struct dentry *dentry, struct inode *inode) -{ - int err = ext4_add_entry(handle, dentry, inode); - if (!err) { - ext4_mark_inode_dirty(handle, inode); - d_instantiate(dentry, inode); - unlock_new_inode(inode); - return 0; - } - drop_nlink(inode); - unlock_new_inode(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 ext4_create(struct inode *dir, struct dentry *dentry, umode_t mode, - struct nameidata *nd) -{ - handle_t *handle; - struct inode *inode; - int err, retries = 0; - - dquot_initialize(dir); - -retry: - handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + - EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL); - err = PTR_ERR(inode); - if (!IS_ERR(inode)) { - inode->i_op = &ext4_file_inode_operations; - inode->i_fop = &ext4_file_operations; - ext4_set_aops(inode); - err = ext4_add_nondir(handle, dentry, inode); - } - ext4_journal_stop(handle); - if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) - goto retry; - return err; -} - -static int ext4_mknod(struct inode *dir, struct dentry *dentry, - umode_t mode, dev_t rdev) -{ - handle_t *handle; - struct inode *inode; - int err, retries = 0; - - if (!new_valid_dev(rdev)) - return -EINVAL; - - dquot_initialize(dir); - -retry: - handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + - EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - inode = ext4_new_inode(handle, dir, mode, &dentry->d_name, 0, NULL); - err = PTR_ERR(inode); - if (!IS_ERR(inode)) { - init_special_inode(inode, inode->i_mode, rdev); -#ifdef CONFIG_EXT4_FS_XATTR - inode->i_op = &ext4_special_inode_operations; -#endif - err = ext4_add_nondir(handle, dentry, inode); - } - ext4_journal_stop(handle); - if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) - goto retry; - return err; -} - -static int ext4_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) -{ - handle_t *handle; - struct inode *inode; - struct buffer_head *dir_block = NULL; - struct ext4_dir_entry_2 *de; - unsigned int blocksize = dir->i_sb->s_blocksize; - int err, retries = 0; - - if (EXT4_DIR_LINK_MAX(dir)) - return -EMLINK; - - dquot_initialize(dir); - -retry: - handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + - EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb)); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - inode = ext4_new_inode(handle, dir, S_IFDIR | mode, - &dentry->d_name, 0, NULL); - err = PTR_ERR(inode); - if (IS_ERR(inode)) - goto out_stop; - - inode->i_op = &ext4_dir_inode_operations; - inode->i_fop = &ext4_dir_operations; - inode->i_size = EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize; - dir_block = ext4_bread(handle, inode, 0, 1, &err); - if (!dir_block) - goto out_clear_inode; - BUFFER_TRACE(dir_block, "get_write_access"); - err = ext4_journal_get_write_access(handle, dir_block); - if (err) - goto out_clear_inode; - 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), - blocksize); - strcpy(de->name, "."); - ext4_set_de_type(dir->i_sb, de, S_IFDIR); - de = ext4_next_entry(de, blocksize); - de->inode = cpu_to_le32(dir->i_ino); - 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); - set_nlink(inode, 2); - BUFFER_TRACE(dir_block, "call ext4_handle_dirty_metadata"); - err = ext4_handle_dirty_metadata(handle, inode, dir_block); - if (err) - goto out_clear_inode; - err = ext4_mark_inode_dirty(handle, inode); - if (!err) - err = ext4_add_entry(handle, dentry, inode); - if (err) { -out_clear_inode: - clear_nlink(inode); - unlock_new_inode(inode); - ext4_mark_inode_dirty(handle, inode); - iput(inode); - goto out_stop; - } - ext4_inc_count(handle, dir); - ext4_update_dx_flag(dir); - err = ext4_mark_inode_dirty(handle, dir); - if (err) - goto out_clear_inode; - d_instantiate(dentry, inode); - unlock_new_inode(inode); -out_stop: - brelse(dir_block); - ext4_journal_stop(handle); - if (err == -ENOSPC && ext4_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 int offset; - struct buffer_head *bh; - struct ext4_dir_entry_2 *de, *de1; - struct super_block *sb; - int err = 0; - - sb = inode->i_sb; - if (inode->i_size < EXT4_DIR_REC_LEN(1) + EXT4_DIR_REC_LEN(2) || - !(bh = ext4_bread(NULL, inode, 0, 0, &err))) { - if (err) - EXT4_ERROR_INODE(inode, - "error %d reading directory lblock 0", err); - else - ext4_warning(inode->i_sb, - "bad directory (dir #%lu) - no data block", - inode->i_ino); - return 1; - } - de = (struct ext4_dir_entry_2 *) bh->b_data; - 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) || - strcmp("..", de1->name)) { - ext4_warning(inode->i_sb, - "bad directory (dir #%lu) - no `.' or `..'", - inode->i_ino); - brelse(bh); - return 1; - } - 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)) { - unsigned int lblock; - err = 0; - brelse(bh); - lblock = offset >> EXT4_BLOCK_SIZE_BITS(sb); - bh = ext4_bread(NULL, inode, lblock, 0, &err); - if (!bh) { - if (err) - EXT4_ERROR_INODE(inode, - "error %d reading directory " - "lblock %u", err, lblock); - offset += sb->s_blocksize; - continue; - } - de = (struct ext4_dir_entry_2 *) bh->b_data; - } - if (ext4_check_dir_entry(inode, NULL, de, bh, offset)) { - de = (struct ext4_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 += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); - de = ext4_next_entry(de, sb->s_blocksize); - } - brelse(bh); - return 1; -} - -/* ext4_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 ext4_orphan_cleanup(). - */ -int ext4_orphan_add(handle_t *handle, struct inode *inode) -{ - struct super_block *sb = inode->i_sb; - struct ext4_iloc iloc; - int err = 0, rc; - - if (!ext4_handle_valid(handle)) - return 0; - - mutex_lock(&EXT4_SB(sb)->s_orphan_lock); - if (!list_empty(&EXT4_I(inode)->i_orphan)) - goto out_unlock; - - /* - * Orphan handling is only valid for files with data blocks - * being truncated, or files being unlinked. Note that we either - * hold i_mutex, or the inode can not be referenced from outside, - * so i_nlink should not be bumped due to race - */ - J_ASSERT((S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) || - S_ISLNK(inode->i_mode)) || inode->i_nlink == 0); - - BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); - err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh); - if (err) - goto out_unlock; - - err = ext4_reserve_inode_write(handle, inode, &iloc); - if (err) - goto out_unlock; - /* - * Due to previous errors inode may be already a part of on-disk - * orphan list. If so skip on-disk list modification. - */ - if (NEXT_ORPHAN(inode) && NEXT_ORPHAN(inode) <= - (le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))) - goto mem_insert; - - /* Insert this inode at the head of the on-disk orphan list... */ - NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan); - EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); - err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); - rc = ext4_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. */ -mem_insert: - if (!err) - list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan); - - jbd_debug(4, "superblock will point to %lu\n", inode->i_ino); - jbd_debug(4, "orphan inode %lu will point to %d\n", - inode->i_ino, NEXT_ORPHAN(inode)); -out_unlock: - mutex_unlock(&EXT4_SB(sb)->s_orphan_lock); - ext4_std_error(inode->i_sb, err); - return err; -} - -/* - * ext4_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 ext4_orphan_del(handle_t *handle, struct inode *inode) -{ - struct list_head *prev; - struct ext4_inode_info *ei = EXT4_I(inode); - struct ext4_sb_info *sbi; - __u32 ino_next; - struct ext4_iloc iloc; - int err = 0; - - /* ext4_handle_valid() assumes a valid handle_t pointer */ - if (handle && !ext4_handle_valid(handle)) - return 0; - - mutex_lock(&EXT4_SB(inode->i_sb)->s_orphan_lock); - if (list_empty(&ei->i_orphan)) - goto out; - - ino_next = NEXT_ORPHAN(inode); - prev = ei->i_orphan.prev; - sbi = EXT4_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 (sbi->s_journal && !handle) - goto out; - - err = ext4_reserve_inode_write(handle, inode, &iloc); - if (err) - goto out_err; - - if (prev == &sbi->s_orphan) { - jbd_debug(4, "superblock will point to %u\n", ino_next); - BUFFER_TRACE(sbi->s_sbh, "get_write_access"); - err = ext4_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 = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); - } else { - struct ext4_iloc iloc2; - struct inode *i_prev = - &list_entry(prev, struct ext4_inode_info, i_orphan)->vfs_inode; - - jbd_debug(4, "orphan inode %lu will point to %u\n", - i_prev->i_ino, ino_next); - err = ext4_reserve_inode_write(handle, i_prev, &iloc2); - if (err) - goto out_brelse; - NEXT_ORPHAN(i_prev) = ino_next; - err = ext4_mark_iloc_dirty(handle, i_prev, &iloc2); - } - if (err) - goto out_brelse; - NEXT_ORPHAN(inode) = 0; - err = ext4_mark_iloc_dirty(handle, inode, &iloc); - -out_err: - ext4_std_error(inode->i_sb, err); -out: - mutex_unlock(&EXT4_SB(inode->i_sb)->s_orphan_lock); - return err; - -out_brelse: - brelse(iloc.bh); - goto out_err; -} - -static int ext4_rmdir(struct inode *dir, struct dentry *dentry) -{ - int retval; - struct inode *inode; - struct buffer_head *bh; - struct ext4_dir_entry_2 *de; - handle_t *handle; - - /* Initialize quotas before so that eventual writes go in - * separate transaction */ - dquot_initialize(dir); - dquot_initialize(dentry->d_inode); - - handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb)); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - retval = -ENOENT; - bh = ext4_find_entry(dir, &dentry->d_name, &de); - if (!bh) - goto end_rmdir; - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - 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 = ext4_delete_entry(handle, dir, de, bh); - if (retval) - goto end_rmdir; - if (!EXT4_DIR_LINK_EMPTY(inode)) - ext4_warning(inode->i_sb, - "empty directory has too many links (%d)", - inode->i_nlink); - inode->i_version++; - clear_nlink(inode); - /* 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; - ext4_orphan_add(handle, inode); - inode->i_ctime = dir->i_ctime = dir->i_mtime = ext4_current_time(inode); - ext4_mark_inode_dirty(handle, inode); - ext4_dec_count(handle, dir); - ext4_update_dx_flag(dir); - ext4_mark_inode_dirty(handle, dir); - -end_rmdir: - ext4_journal_stop(handle); - brelse(bh); - return retval; -} - -static int ext4_unlink(struct inode *dir, struct dentry *dentry) -{ - int retval; - struct inode *inode; - struct buffer_head *bh; - struct ext4_dir_entry_2 *de; - handle_t *handle; - - trace_ext4_unlink_enter(dir, dentry); - /* Initialize quotas before so that eventual writes go - * in separate transaction */ - dquot_initialize(dir); - dquot_initialize(dentry->d_inode); - - handle = ext4_journal_start(dir, EXT4_DELETE_TRANS_BLOCKS(dir->i_sb)); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - retval = -ENOENT; - bh = ext4_find_entry(dir, &dentry->d_name, &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) { - ext4_warning(inode->i_sb, - "Deleting nonexistent file (%lu), %d", - inode->i_ino, inode->i_nlink); - set_nlink(inode, 1); - } - retval = ext4_delete_entry(handle, dir, de, bh); - if (retval) - goto end_unlink; - dir->i_ctime = dir->i_mtime = ext4_current_time(dir); - ext4_update_dx_flag(dir); - ext4_mark_inode_dirty(handle, dir); - drop_nlink(inode); - if (!inode->i_nlink) - ext4_orphan_add(handle, inode); - inode->i_ctime = ext4_current_time(inode); - ext4_mark_inode_dirty(handle, inode); - retval = 0; - -end_unlink: - ext4_journal_stop(handle); - brelse(bh); - trace_ext4_unlink_exit(dentry, retval); - return retval; -} - -static int ext4_symlink(struct inode *dir, - struct dentry *dentry, const char *symname) -{ - handle_t *handle; - struct inode *inode; - int l, err, retries = 0; - int credits; - - l = strlen(symname)+1; - if (l > dir->i_sb->s_blocksize) - return -ENAMETOOLONG; - - dquot_initialize(dir); - - if (l > EXT4_N_BLOCKS * 4) { - /* - * For non-fast symlinks, we just allocate inode and put it on - * orphan list in the first transaction => we need bitmap, - * group descriptor, sb, inode block, quota blocks, and - * possibly selinux xattr blocks. - */ - credits = 4 + EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) + - EXT4_XATTR_TRANS_BLOCKS; - } else { - /* - * Fast symlink. We have to add entry to directory - * (EXT4_DATA_TRANS_BLOCKS + EXT4_INDEX_EXTRA_TRANS_BLOCKS), - * allocate new inode (bitmap, group descriptor, inode block, - * quota blocks, sb is already counted in previous macros). - */ - credits = EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3 + - EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb); - } -retry: - handle = ext4_journal_start(dir, credits); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - inode = ext4_new_inode(handle, dir, S_IFLNK|S_IRWXUGO, - &dentry->d_name, 0, NULL); - err = PTR_ERR(inode); - if (IS_ERR(inode)) - goto out_stop; - - if (l > EXT4_N_BLOCKS * 4) { - inode->i_op = &ext4_symlink_inode_operations; - ext4_set_aops(inode); - /* - * We cannot call page_symlink() with transaction started - * because it calls into ext4_write_begin() which can wait - * for transaction commit if we are running out of space - * and thus we deadlock. So we have to stop transaction now - * and restart it when symlink contents is written. - * - * To keep fs consistent in case of crash, we have to put inode - * to orphan list in the mean time. - */ - drop_nlink(inode); - err = ext4_orphan_add(handle, inode); - ext4_journal_stop(handle); - if (err) - goto err_drop_inode; - err = __page_symlink(inode, symname, l, 1); - if (err) - goto err_drop_inode; - /* - * Now inode is being linked into dir (EXT4_DATA_TRANS_BLOCKS - * + EXT4_INDEX_EXTRA_TRANS_BLOCKS), inode is also modified - */ - handle = ext4_journal_start(dir, - EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 1); - if (IS_ERR(handle)) { - err = PTR_ERR(handle); - goto err_drop_inode; - } - set_nlink(inode, 1); - err = ext4_orphan_del(handle, inode); - if (err) { - ext4_journal_stop(handle); - clear_nlink(inode); - goto err_drop_inode; - } - } else { - /* clear the extent format for fast symlink */ - ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS); - inode->i_op = &ext4_fast_symlink_inode_operations; - memcpy((char *)&EXT4_I(inode)->i_data, symname, l); - inode->i_size = l-1; - } - EXT4_I(inode)->i_disksize = inode->i_size; - err = ext4_add_nondir(handle, dentry, inode); -out_stop: - ext4_journal_stop(handle); - if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) - goto retry; - return err; -err_drop_inode: - unlock_new_inode(inode); - iput(inode); - return err; -} - -static int ext4_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 >= EXT4_LINK_MAX) - return -EMLINK; - - dquot_initialize(dir); - -retry: - handle = ext4_journal_start(dir, EXT4_DATA_TRANS_BLOCKS(dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(dir)) - ext4_handle_sync(handle); - - inode->i_ctime = ext4_current_time(inode); - ext4_inc_count(handle, inode); - ihold(inode); - - err = ext4_add_entry(handle, dentry, inode); - if (!err) { - ext4_mark_inode_dirty(handle, inode); - d_instantiate(dentry, inode); - } else { - drop_nlink(inode); - iput(inode); - } - ext4_journal_stop(handle); - if (err == -ENOSPC && ext4_should_retry_alloc(dir->i_sb, &retries)) - goto retry; - return err; -} - -#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 - * higher-level routines. - */ -static int ext4_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 ext4_dir_entry_2 *old_de, *new_de; - int retval, force_da_alloc = 0; - - dquot_initialize(old_dir); - dquot_initialize(new_dir); - - old_bh = new_bh = dir_bh = NULL; - - /* Initialize quotas before so that eventual writes go - * in separate transaction */ - if (new_dentry->d_inode) - dquot_initialize(new_dentry->d_inode); - handle = ext4_journal_start(old_dir, 2 * - EXT4_DATA_TRANS_BLOCKS(old_dir->i_sb) + - EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2); - if (IS_ERR(handle)) - return PTR_ERR(handle); - - if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) - ext4_handle_sync(handle); - - old_bh = ext4_find_entry(old_dir, &old_dentry->d_name, &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 = ext4_find_entry(new_dir, &new_dentry->d_name, &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 = 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_sb->s_blocksize)) != old_dir->i_ino) - goto end_rename; - retval = -EMLINK; - if (!new_inode && new_dir != old_dir && - EXT4_DIR_LINK_MAX(new_dir)) - goto end_rename; - BUFFER_TRACE(dir_bh, "get_write_access"); - retval = ext4_journal_get_write_access(handle, dir_bh); - if (retval) - goto end_rename; - } - if (!new_bh) { - retval = ext4_add_entry(handle, new_dentry, old_inode); - if (retval) - goto end_rename; - } else { - BUFFER_TRACE(new_bh, "get write access"); - retval = ext4_journal_get_write_access(handle, new_bh); - if (retval) - goto end_rename; - new_de->inode = cpu_to_le32(old_inode->i_ino); - if (EXT4_HAS_INCOMPAT_FEATURE(new_dir->i_sb, - EXT4_FEATURE_INCOMPAT_FILETYPE)) - new_de->file_type = old_de->file_type; - new_dir->i_version++; - new_dir->i_ctime = new_dir->i_mtime = - ext4_current_time(new_dir); - ext4_mark_inode_dirty(handle, new_dir); - BUFFER_TRACE(new_bh, "call ext4_handle_dirty_metadata"); - retval = ext4_handle_dirty_metadata(handle, new_dir, new_bh); - if (unlikely(retval)) { - ext4_std_error(new_dir->i_sb, retval); - goto end_rename; - } - brelse(new_bh); - new_bh = NULL; - } - - /* - * Like most other Unix systems, set the ctime for inodes on a - * rename. - */ - old_inode->i_ctime = ext4_current_time(old_inode); - ext4_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 = ext4_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 ext4_dir_entry_2 *old_de2; - - old_bh2 = ext4_find_entry(old_dir, &old_dentry->d_name, &old_de2); - if (old_bh2) { - retval = ext4_delete_entry(handle, old_dir, - old_de2, old_bh2); - brelse(old_bh2); - } - } - if (retval) { - ext4_warning(old_dir->i_sb, - "Deleting old file (%lu), %d, error=%d", - old_dir->i_ino, old_dir->i_nlink, retval); - } - - if (new_inode) { - ext4_dec_count(handle, new_inode); - new_inode->i_ctime = ext4_current_time(new_inode); - } - old_dir->i_ctime = old_dir->i_mtime = ext4_current_time(old_dir); - ext4_update_dx_flag(old_dir); - if (dir_bh) { - 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"); - retval = ext4_handle_dirty_metadata(handle, old_inode, dir_bh); - if (retval) { - ext4_std_error(old_dir->i_sb, retval); - goto end_rename; - } - ext4_dec_count(handle, old_dir); - if (new_inode) { - /* checked empty_dir above, can't have another parent, - * ext4_dec_count() won't work for many-linked dirs */ - clear_nlink(new_inode); - } else { - ext4_inc_count(handle, new_dir); - ext4_update_dx_flag(new_dir); - ext4_mark_inode_dirty(handle, new_dir); - } - } - ext4_mark_inode_dirty(handle, old_dir); - if (new_inode) { - ext4_mark_inode_dirty(handle, new_inode); - if (!new_inode->i_nlink) - ext4_orphan_add(handle, new_inode); - if (!test_opt(new_dir->i_sb, NO_AUTO_DA_ALLOC)) - force_da_alloc = 1; - } - retval = 0; - -end_rename: - brelse(dir_bh); - brelse(old_bh); - brelse(new_bh); - ext4_journal_stop(handle); - if (retval == 0 && force_da_alloc) - ext4_alloc_da_blocks(old_inode); - return retval; -} - -/* - * directories can handle most operations... - */ -const struct inode_operations ext4_dir_inode_operations = { - .create = ext4_create, - .lookup = ext4_lookup, - .link = ext4_link, - .unlink = ext4_unlink, - .symlink = ext4_symlink, - .mkdir = ext4_mkdir, - .rmdir = ext4_rmdir, - .mknod = ext4_mknod, - .rename = ext4_rename, - .setattr = ext4_setattr, -#ifdef CONFIG_EXT4_FS_XATTR - .setxattr = generic_setxattr, - .getxattr = generic_getxattr, - .listxattr = ext4_listxattr, - .removexattr = generic_removexattr, -#endif - .get_acl = ext4_get_acl, - .fiemap = ext4_fiemap, -}; - -const struct inode_operations ext4_special_inode_operations = { - .setattr = ext4_setattr, -#ifdef CONFIG_EXT4_FS_XATTR - .setxattr = generic_setxattr, - .getxattr = generic_getxattr, - .listxattr = ext4_listxattr, - .removexattr = generic_removexattr, -#endif - .get_acl = ext4_get_acl, -}; |