bcachefs: Don't issue discards when in nochanges mode

When the nochanges option is selected, we're supposed to never issue
writes. Unfortunately, it seems discards were missed when implemnting
this, leading to some painful filesystem corruption.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

diff --git a/fs/bcachefs/alloc_background.c b/fs/bcachefs/alloc_background.c
index 700d1e00aaf9264c0faccffa531186595a8c17b0..fac040aa0d5a2096b4a7a3fe401ed8be03a45df7 100644 (file)
--- a/fs/bcachefs/alloc_background.c
+++ b/fs/bcachefs/alloc_background.c
@@ -801,7 +801,8 @@ static int push_invalidated_bucket(struct bch_fs *c, struct bch_dev *ca, u64 b)
 
 static void discard_one_bucket(struct bch_fs *c, struct bch_dev *ca, u64 b)
 {
-       if (ca->mi.discard &&
+       if (!c->opts.nochanges &&
+           ca->mi.discard &&
            bdev_max_discard_sectors(ca->disk_sb.bdev))
                blkdev_issue_discard(ca->disk_sb.bdev, bucket_to_sector(ca, b),
                                     ca->mi.bucket_size, GFP_NOFS);

diff --git a/fs/bcachefs/journal_reclaim.c b/fs/bcachefs/journal_reclaim.c
index d72b17dc935ac805ae338c342f4c03d3e86228c5..84cc952a7ac56a5db289627c43ab53e7072bb06e 100644 (file)
--- a/fs/bcachefs/journal_reclaim.c
+++ b/fs/bcachefs/journal_reclaim.c
@@ -286,7 +286,8 @@ void bch2_journal_do_discards(struct journal *j)
                struct journal_device *ja = &ca->journal;
 
                while (should_discard_bucket(j, ja)) {
-                       if (ca->mi.discard &&
+                       if (!c->opts.nochanges &&
+                           ca->mi.discard &&
                            bdev_max_discard_sectors(ca->disk_sb.bdev))
                                blkdev_issue_discard(ca->disk_sb.bdev,
                                        bucket_to_sector(ca,