This is a note to let you know that I've just added the patch titled
ext4: mark group as trimmed only if it was fully scanned
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ext4-mark-group-as-trimmed-only-if-it-was-fully-scan.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e8cd80fe901e4991c8fdd9fdc9d391c8c5ca1dc9
Author: Dmitry Monakhov <dmtrmonakhov@xxxxxxxxxxxxxx>
Date: Sun Apr 17 20:03:15 2022 +0300
ext4: mark group as trimmed only if it was fully scanned
[ Upstream commit d63c00ea435a5352f486c259665a4ced60399421 ]
Otherwise nonaligned fstrim calls will works inconveniently for iterative
scanners, for example:
// trim [0,16MB] for group-1, but mark full group as trimmed
fstrim -o $((1024*1024*128)) -l $((1024*1024*16)) ./m
// handle [16MB,16MB] for group-1, do nothing because group already has the flag.
fstrim -o $((1024*1024*144)) -l $((1024*1024*16)) ./m
[ Update function documentation for ext4_trim_all_free -- TYT ]
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1650214995-860245-1-git-send-email-dmtrmonakhov@xxxxxxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Cc: stable@xxxxxxxxxx
Stable-dep-of: 45e4ab320c9b ("ext4: move setting of trimmed bit into ext4_try_to_trim_range()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index db6bc24936479..7cd2f2c07858f 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -5248,6 +5248,7 @@ static int ext4_try_to_trim_range(struct super_block *sb,
* @start: first group block to examine
* @max: last group block to examine
* @minblocks: minimum extent block count
+ * @set_trimmed: set the trimmed flag if at least one block is trimmed
*
* ext4_trim_all_free walks through group's buddy bitmap searching for free
* extents. When the free block is found, ext4_trim_extent is called to TRIM
@@ -5262,7 +5263,7 @@ static int ext4_try_to_trim_range(struct super_block *sb,
static ext4_grpblk_t
ext4_trim_all_free(struct super_block *sb, ext4_group_t group,
ext4_grpblk_t start, ext4_grpblk_t max,
- ext4_grpblk_t minblocks)
+ ext4_grpblk_t minblocks, bool set_trimmed)
{
struct ext4_buddy e4b;
int ret;
@@ -5281,7 +5282,7 @@ ext4_trim_all_free(struct super_block *sb, ext4_group_t group,
if (!EXT4_MB_GRP_WAS_TRIMMED(e4b.bd_info) ||
minblocks < EXT4_SB(sb)->s_last_trim_minblks) {
ret = ext4_try_to_trim_range(sb, &e4b, start, max, minblocks);
- if (ret >= 0)
+ if (ret >= 0 && set_trimmed)
EXT4_MB_GRP_SET_TRIMMED(e4b.bd_info);
} else {
ret = 0;
@@ -5318,6 +5319,7 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
ext4_fsblk_t first_data_blk =
le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block);
ext4_fsblk_t max_blks = ext4_blocks_count(EXT4_SB(sb)->s_es);
+ bool whole_group, eof = false;
int ret = 0;
start = range->start >> sb->s_blocksize_bits;
@@ -5336,8 +5338,10 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
if (minlen > EXT4_CLUSTERS_PER_GROUP(sb))
goto out;
}
- if (end >= max_blks)
+ if (end >= max_blks - 1) {
end = max_blks - 1;
+ eof = true;
+ }
if (end <= first_data_blk)
goto out;
if (start < first_data_blk)
@@ -5351,6 +5355,7 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
/* end now represents the last cluster to discard in this group */
end = EXT4_CLUSTERS_PER_GROUP(sb) - 1;
+ whole_group = true;
for (group = first_group; group <= last_group; group++) {
grp = ext4_get_group_info(sb, group);
@@ -5367,12 +5372,13 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range)
* change it for the last group, note that last_cluster is
* already computed earlier by ext4_get_group_no_and_offset()
*/
- if (group == last_group)
+ if (group == last_group) {
end = last_cluster;
-
+ whole_group = eof ? true : end == EXT4_CLUSTERS_PER_GROUP(sb) - 1;
+ }
if (grp->bb_free >= minlen) {
cnt = ext4_trim_all_free(sb, group, first_cluster,
- end, minlen);
+ end, minlen, whole_group);
if (cnt < 0) {
ret = cnt;
break;
