diff options
Diffstat (limited to 'fs/ext4/namei.c')
| -rw-r--r-- | fs/ext4/namei.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 13f0cadb1238..cc986b824181 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -2395,19 +2395,22 @@ 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); } /* |