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-rw-r--r--fs/ext4/namei.c64
1 files changed, 26 insertions, 38 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 13f0cadb1238..c1cf020d1889 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1342,13 +1342,12 @@ static struct buffer_head * ext4_find_entry (struct inode *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;
+ ext4_lblk_t start, block;
const u8 *name = d_name->name;
- int ra_max = 0; /* Number of bh's in the readahead
+ size_t ra_max = 0; /* Number of bh's in the readahead
buffer, bh_use[] */
- int ra_ptr = 0; /* Current index into readahead
+ size_t ra_ptr = 0; /* Current index into readahead
buffer */
- int num = 0;
ext4_lblk_t nblocks;
int i, namelen, retval;
struct ext4_filename fname;
@@ -1411,31 +1410,17 @@ restart:
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);
- if (IS_ERR(bh)) {
- if (ra_max == 0) {
- ret = bh;
- goto cleanup_and_exit;
- }
- break;
- }
- bh_use[ra_max] = bh;
- if (bh)
- ll_rw_block(REQ_OP_READ,
- REQ_META | REQ_PRIO,
- 1, &bh);
+ if (block < start)
+ ra_max = start - block;
+ else
+ ra_max = nblocks - block;
+ ra_max = min(ra_max, ARRAY_SIZE(bh_use));
+ retval = ext4_bread_batch(dir, block, ra_max,
+ false /* wait */, bh_use);
+ if (retval) {
+ ret = ERR_PTR(retval);
+ ra_max = 0;
+ goto cleanup_and_exit;
}
}
if ((bh = bh_use[ra_ptr++]) == NULL)
@@ -2395,19 +2380,22 @@ out:
}
/*
- * DIR_NLINK feature is set if 1) nlinks > EXT4_LINK_MAX or 2) nlinks == 2,
- * since this indicates that nlinks count was previously 1.
+ * Set directory link count to 1 if nlinks > EXT4_LINK_MAX, or if nlinks == 2
+ * since this indicates that nlinks count was previously 1 to avoid overflowing
+ * the 16-bit i_links_count field on disk. Directories with i_nlink == 1 mean
+ * that subdirectory link counts are not being maintained accurately.
+ *
+ * The caller has already checked for i_nlink overflow in case the DIR_LINK
+ * feature is not enabled and returned -EMLINK. The is_dx() check is a proxy
+ * for checking S_ISDIR(inode) (since the INODE_INDEX feature will not be set
+ * on regular files) and to avoid creating huge/slow non-HTREE directories.
*/
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_feature_dir_nlink(inode->i_sb);
- }
- }
+ if (is_dx(inode) &&
+ (inode->i_nlink > EXT4_LINK_MAX || inode->i_nlink == 2))
+ set_nlink(inode, 1);
}
/*