3.16.81-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Based on commit 7bc04c5c2cc4 "ext4: fix use-after-free race with
debug_want_extra_isize". We don't have that bug but this will make it
easier to backport commit 4ea99936a163 "ext4: add more paranoia
checking in ext4_expand_extra_isize handling".
Cc: Barret Rhoden <brho@xxxxxxxxxx>
Cc: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3423,6 +3423,36 @@ int ext4_calculate_overhead(struct super
return 0;
}
+static void ext4_clamp_want_extra_isize(struct super_block *sb)
+{
+ struct ext4_sb_info *sbi = EXT4_SB(sb);
+ struct ext4_super_block *es = sbi->s_es;
+
+ /* determine the minimum size of new large inodes, if present */
+ if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
+ sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
+ EXT4_GOOD_OLD_INODE_SIZE;
+ if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
+ EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
+ if (sbi->s_want_extra_isize <
+ le16_to_cpu(es->s_want_extra_isize))
+ sbi->s_want_extra_isize =
+ le16_to_cpu(es->s_want_extra_isize);
+ if (sbi->s_want_extra_isize <
+ le16_to_cpu(es->s_min_extra_isize))
+ sbi->s_want_extra_isize =
+ le16_to_cpu(es->s_min_extra_isize);
+ }
+ }
+ /* Check if enough inode space is available */
+ if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
+ sbi->s_inode_size) {
+ sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
+ EXT4_GOOD_OLD_INODE_SIZE;
+ ext4_msg(sb, KERN_INFO,
+ "required extra inode space not available");
+ }
+}
static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
{
@@ -4245,30 +4275,7 @@ no_journal:
if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
sb->s_flags |= MS_RDONLY;
- /* determine the minimum size of new large inodes, if present */
- if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
- sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
- EXT4_GOOD_OLD_INODE_SIZE;
- if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
- EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
- if (sbi->s_want_extra_isize <
- le16_to_cpu(es->s_want_extra_isize))
- sbi->s_want_extra_isize =
- le16_to_cpu(es->s_want_extra_isize);
- if (sbi->s_want_extra_isize <
- le16_to_cpu(es->s_min_extra_isize))
- sbi->s_want_extra_isize =
- le16_to_cpu(es->s_min_extra_isize);
- }
- }
- /* Check if enough inode space is available */
- if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
- sbi->s_inode_size) {
- sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
- EXT4_GOOD_OLD_INODE_SIZE;
- ext4_msg(sb, KERN_INFO, "required extra inode space not"
- "available");
- }
+ ext4_clamp_want_extra_isize(sb);
err = ext4_reserve_clusters(sbi, ext4_calculate_resv_clusters(sb));
if (err) {
