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Diffstat (limited to 'fs/ext4/namei.c')
-rw-r--r--fs/ext4/namei.c130
1 files changed, 85 insertions, 45 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 0482495..a5ba1a8 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -165,7 +165,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
struct dx_hash_info *hinfo, struct dx_map_entry map[]);
static void dx_sort_map(struct dx_map_entry *map, unsigned count);
static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
- struct dx_map_entry *offsets, int count);
+ struct dx_map_entry *offsets, int count, unsigned blocksize);
static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
static void dx_insert_block(struct dx_frame *frame,
u32 hash, ext4_lblk_t block);
@@ -180,14 +180,38 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
struct inode *inode);
+unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
+{
+ unsigned len = le16_to_cpu(dlen);
+
+ if (len == EXT4_MAX_REC_LEN || len == 0)
+ return blocksize;
+ return (len & 65532) | ((len & 3) << 16);
+}
+
+__le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
+{
+ if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
+ BUG();
+ if (len < 65536)
+ return cpu_to_le16(len);
+ if (len == blocksize) {
+ if (blocksize == 65536)
+ return cpu_to_le16(EXT4_MAX_REC_LEN);
+ else
+ return cpu_to_le16(0);
+ }
+ return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
+}
+
/*
* p is at least 6 bytes before the end of page
*/
static inline struct ext4_dir_entry_2 *
-ext4_next_entry(struct ext4_dir_entry_2 *p)
+ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
{
return (struct ext4_dir_entry_2 *)((char *)p +
- ext4_rec_len_from_disk(p->rec_len));
+ ext4_rec_len_from_disk(p->rec_len, blocksize));
}
/*
@@ -294,7 +318,7 @@ static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_ent
space += EXT4_DIR_REC_LEN(de->name_len);
names++;
}
- de = ext4_next_entry(de);
+ de = ext4_next_entry(de, size);
}
printk("(%i)\n", names);
return (struct stats) { names, space, 1 };
@@ -585,7 +609,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
top = (struct ext4_dir_entry_2 *) ((char *) de +
dir->i_sb->s_blocksize -
EXT4_DIR_REC_LEN(0));
- for (; de < top; de = ext4_next_entry(de)) {
+ for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
if (!ext4_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
(block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
+((char *)de - bh->b_data))) {
@@ -663,7 +687,7 @@ int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
}
if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
- de = ext4_next_entry(de);
+ de = ext4_next_entry(de, dir->i_sb->s_blocksize);
if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
goto errout;
count++;
@@ -732,7 +756,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
cond_resched();
}
/* XXX: do we need to check rec_len == 0 case? -Chris */
- de = ext4_next_entry(de);
+ de = ext4_next_entry(de, blocksize);
}
return count;
}
@@ -832,7 +856,8 @@ static inline int search_dirblock(struct buffer_head *bh,
return 1;
}
/* prevent looping on a bad block */
- de_len = ext4_rec_len_from_disk(de->rec_len);
+ de_len = ext4_rec_len_from_disk(de->rec_len,
+ dir->i_sb->s_blocksize);
if (de_len <= 0)
return -1;
offset += de_len;
@@ -996,7 +1021,7 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct q
de = (struct ext4_dir_entry_2 *) bh->b_data;
top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize -
EXT4_DIR_REC_LEN(0));
- for (; de < top; de = ext4_next_entry(de)) {
+ for (; de < top; de = ext4_next_entry(de, sb->s_blocksize)) {
int off = (block << EXT4_BLOCK_SIZE_BITS(sb))
+ ((char *) de - bh->b_data);
@@ -1109,7 +1134,8 @@ static inline void ext4_set_de_type(struct super_block *sb,
* Returns pointer to last entry moved.
*/
static struct ext4_dir_entry_2 *
-dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
+dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
+ unsigned blocksize)
{
unsigned rec_len = 0;
@@ -1118,7 +1144,7 @@ dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
rec_len = EXT4_DIR_REC_LEN(de->name_len);
memcpy (to, de, rec_len);
((struct ext4_dir_entry_2 *) to)->rec_len =
- ext4_rec_len_to_disk(rec_len);
+ ext4_rec_len_to_disk(rec_len, blocksize);
de->inode = 0;
map++;
to += rec_len;
@@ -1137,12 +1163,12 @@ static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
prev = to = de;
while ((char*)de < base + blocksize) {
- next = ext4_next_entry(de);
+ next = ext4_next_entry(de, blocksize);
if (de->inode && de->name_len) {
rec_len = EXT4_DIR_REC_LEN(de->name_len);
if (de > to)
memmove(to, de, rec_len);
- to->rec_len = ext4_rec_len_to_disk(rec_len);
+ to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
prev = to;
to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
}
@@ -1215,10 +1241,12 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
hash2, split, count-split));
/* Fancy dance to stay within two buffers */
- de2 = dx_move_dirents(data1, data2, map + split, count - split);
+ de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
de = dx_pack_dirents(data1, blocksize);
- de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de);
- de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2);
+ de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de,
+ blocksize);
+ de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2,
+ blocksize);
dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
@@ -1268,6 +1296,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
unsigned int offset = 0;
+ unsigned int blocksize = dir->i_sb->s_blocksize;
unsigned short reclen;
int nlen, rlen, err;
char *top;
@@ -1275,7 +1304,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
reclen = EXT4_DIR_REC_LEN(namelen);
if (!de) {
de = (struct ext4_dir_entry_2 *)bh->b_data;
- top = bh->b_data + dir->i_sb->s_blocksize - reclen;
+ top = bh->b_data + blocksize - reclen;
while ((char *) de <= top) {
if (!ext4_check_dir_entry("ext4_add_entry", dir, de,
bh, offset)) {
@@ -1287,7 +1316,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
return -EEXIST;
}
nlen = EXT4_DIR_REC_LEN(de->name_len);
- rlen = ext4_rec_len_from_disk(de->rec_len);
+ rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
if ((de->inode? rlen - nlen: rlen) >= reclen)
break;
de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
@@ -1306,11 +1335,11 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
/* By now the buffer is marked for journaling */
nlen = EXT4_DIR_REC_LEN(de->name_len);
- rlen = ext4_rec_len_from_disk(de->rec_len);
+ rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
if (de->inode) {
struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
- de1->rec_len = ext4_rec_len_to_disk(rlen - nlen);
- de->rec_len = ext4_rec_len_to_disk(nlen);
+ de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, blocksize);
+ de->rec_len = ext4_rec_len_to_disk(nlen, blocksize);
de = de1;
}
de->file_type = EXT4_FT_UNKNOWN;
@@ -1380,7 +1409,7 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
/* The 0th block becomes the root, move the dirents out */
fde = &root->dotdot;
de = (struct ext4_dir_entry_2 *)((char *)fde +
- ext4_rec_len_from_disk(fde->rec_len));
+ ext4_rec_len_from_disk(fde->rec_len, blocksize));
if ((char *) de >= (((char *) root) + blocksize)) {
ext4_error(dir->i_sb, __func__,
"invalid rec_len for '..' in inode %lu",
@@ -1402,12 +1431,14 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
memcpy (data1, de, len);
de = (struct ext4_dir_entry_2 *) data1;
top = data1 + len;
- while ((char *)(de2 = ext4_next_entry(de)) < top)
+ while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
de = de2;
- de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de);
+ de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de,
+ blocksize);
/* Initialize the root; the dot dirents already exist */
de = (struct ext4_dir_entry_2 *) (&root->dotdot);
- de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2));
+ de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
+ blocksize);
memset (&root->info, 0, sizeof(root->info));
root->info.info_length = sizeof(root->info);
root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
@@ -1488,7 +1519,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
return retval;
de = (struct ext4_dir_entry_2 *) bh->b_data;
de->inode = 0;
- de->rec_len = ext4_rec_len_to_disk(blocksize);
+ de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize);
return add_dirent_to_buf(handle, dentry, inode, de, bh);
}
@@ -1551,7 +1582,8 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
goto cleanup;
node2 = (struct dx_node *)(bh2->b_data);
entries2 = node2->entries;
- node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize);
+ node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
+ sb->s_blocksize);
node2->fake.inode = 0;
BUFFER_TRACE(frame->bh, "get_write_access");
err = ext4_journal_get_write_access(handle, frame->bh);
@@ -1639,6 +1671,7 @@ static int ext4_delete_entry(handle_t *handle,
struct buffer_head *bh)
{
struct ext4_dir_entry_2 *de, *pde;
+ unsigned int blocksize = dir->i_sb->s_blocksize;
int i;
i = 0;
@@ -1652,8 +1685,11 @@ static int ext4_delete_entry(handle_t *handle,
ext4_journal_get_write_access(handle, bh);
if (pde)
pde->rec_len = ext4_rec_len_to_disk(
- ext4_rec_len_from_disk(pde->rec_len) +
- ext4_rec_len_from_disk(de->rec_len));
+ ext4_rec_len_from_disk(pde->rec_len,
+ blocksize) +
+ ext4_rec_len_from_disk(de->rec_len,
+ blocksize),
+ blocksize);
else
de->inode = 0;
dir->i_version++;
@@ -1661,9 +1697,9 @@ static int ext4_delete_entry(handle_t *handle,
ext4_handle_dirty_metadata(handle, dir, bh);
return 0;
}
- i += ext4_rec_len_from_disk(de->rec_len);
+ i += ext4_rec_len_from_disk(de->rec_len, blocksize);
pde = de;
- de = ext4_next_entry(de);
+ de = ext4_next_entry(de, blocksize);
}
return -ENOENT;
}
@@ -1793,6 +1829,7 @@ static int ext4_mkdir(struct inode *dir, struct dentry *dentry, int mode)
struct inode *inode;
struct buffer_head *dir_block;
struct ext4_dir_entry_2 *de;
+ unsigned int blocksize = dir->i_sb->s_blocksize;
int err, retries = 0;
if (EXT4_DIR_LINK_MAX(dir))
@@ -1824,13 +1861,14 @@ retry:
de = (struct ext4_dir_entry_2 *) dir_block->b_data;
de->inode = cpu_to_le32(inode->i_ino);
de->name_len = 1;
- de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len));
+ de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
+ blocksize);
strcpy(de->name, ".");
ext4_set_de_type(dir->i_sb, de, S_IFDIR);
- de = ext4_next_entry(de);
+ de = ext4_next_entry(de, blocksize);
de->inode = cpu_to_le32(dir->i_ino);
- de->rec_len = ext4_rec_len_to_disk(inode->i_sb->s_blocksize -
- EXT4_DIR_REC_LEN(1));
+ de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(1),
+ blocksize);
de->name_len = 2;
strcpy(de->name, "..");
ext4_set_de_type(dir->i_sb, de, S_IFDIR);
@@ -1885,7 +1923,7 @@ static int empty_dir(struct inode *inode)
return 1;
}
de = (struct ext4_dir_entry_2 *) bh->b_data;
- de1 = ext4_next_entry(de);
+ de1 = ext4_next_entry(de, sb->s_blocksize);
if (le32_to_cpu(de->inode) != inode->i_ino ||
!le32_to_cpu(de1->inode) ||
strcmp(".", de->name) ||
@@ -1896,9 +1934,9 @@ static int empty_dir(struct inode *inode)
brelse(bh);
return 1;
}
- offset = ext4_rec_len_from_disk(de->rec_len) +
- ext4_rec_len_from_disk(de1->rec_len);
- de = ext4_next_entry(de1);
+ offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
+ ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
+ de = ext4_next_entry(de1, sb->s_blocksize);
while (offset < inode->i_size) {
if (!bh ||
(void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
@@ -1927,8 +1965,8 @@ static int empty_dir(struct inode *inode)
brelse(bh);
return 0;
}
- offset += ext4_rec_len_from_disk(de->rec_len);
- de = ext4_next_entry(de);
+ offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
+ de = ext4_next_entry(de, sb->s_blocksize);
}
brelse(bh);
return 1;
@@ -2297,8 +2335,8 @@ retry:
return err;
}
-#define PARENT_INO(buffer) \
- (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer))->inode)
+#define PARENT_INO(buffer, size) \
+ (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer), size)->inode)
/*
* Anybody can rename anything with this: the permission checks are left to the
@@ -2358,7 +2396,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
dir_bh = ext4_bread(handle, old_inode, 0, 0, &retval);
if (!dir_bh)
goto end_rename;
- if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
+ if (le32_to_cpu(PARENT_INO(dir_bh->b_data,
+ old_dir->i_sb->s_blocksize)) != old_dir->i_ino)
goto end_rename;
retval = -EMLINK;
if (!new_inode && new_dir != old_dir &&
@@ -2430,7 +2469,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
if (dir_bh) {
BUFFER_TRACE(dir_bh, "get_write_access");
ext4_journal_get_write_access(handle, dir_bh);
- PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
+ PARENT_INO(dir_bh->b_data, new_dir->i_sb->s_blocksize) =
+ cpu_to_le32(new_dir->i_ino);
BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata");
ext4_handle_dirty_metadata(handle, old_dir, dir_bh);
ext4_dec_count(handle, old_dir);