4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jan Kara jack@suse.cz
[ Upstream commit 5229a658f6453362fbb9da6bf96872ef25a7097e ]
Len Brown has reported that system suspend sometimes fail due to inability to freeze a task working in ext4_trim_fs() for one minute. Trimming a large filesystem on a disk that slowly processes discard requests can indeed take a long time. Since discard is just an advisory call, it is perfectly fine to interrupt it at any time and the return number of discarded blocks until that moment. Do that when we detect the task is being frozen.
Cc: stable@kernel.org Reported-by: Len Brown lenb@kernel.org Suggested-by: Dave Chinner david@fromorbit.com References: https://bugzilla.kernel.org/show_bug.cgi?id=216322 Signed-off-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/20230913150504.9054-2-jack@suse.cz Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/mballoc.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 94b3bf8173e20..fb2f255c48e81 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -16,6 +16,7 @@ #include <linux/slab.h> #include <linux/nospec.h> #include <linux/backing-dev.h> +#include <linux/freezer.h> #include <trace/events/ext4.h>
#ifdef CONFIG_EXT4_DEBUG @@ -5194,6 +5195,11 @@ static ext4_grpblk_t ext4_last_grp_cluster(struct super_block *sb, EXT4_CLUSTER_BITS(sb); }
+static bool ext4_trim_interrupted(void) +{ + return fatal_signal_pending(current) || freezing(current); +} + static int ext4_try_to_trim_range(struct super_block *sb, struct ext4_buddy *e4b, ext4_grpblk_t start, ext4_grpblk_t max, ext4_grpblk_t minblocks) @@ -5225,8 +5231,8 @@ static int ext4_try_to_trim_range(struct super_block *sb, free_count += next - start; start = next + 1;
- if (fatal_signal_pending(current)) - return -ERESTARTSYS; + if (ext4_trim_interrupted()) + return count;
if (need_resched()) { ext4_unlock_group(sb, e4b->bd_group); @@ -5353,6 +5359,8 @@ int ext4_trim_fs(struct super_block *sb, struct fstrim_range *range) end = EXT4_CLUSTERS_PER_GROUP(sb) - 1;
for (group = first_group; group <= last_group; group++) { + if (ext4_trim_interrupted()) + break; grp = ext4_get_group_info(sb, group); /* We only do this if the grp has never been initialized */ if (unlikely(EXT4_MB_GRP_NEED_INIT(grp))) {