diff options
Diffstat (limited to 'fs/ext4/namei.c')
| -rw-r--r-- | fs/ext4/namei.c | 64 |
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); } /* |