Btrfs: fix max chunk size check in chunk allocator
Fix a bug, where in case we need to adjust stripe_size so that the
length of the resulting chunk is less than or equal to max_chunk_size,
DUP chunks turn out to be only half as big as they could be.
Cc: Arne Jansen <sensille@gmx.net>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 759d024..ce289af 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3324,12 +3324,14 @@
stripe_size = devices_info[ndevs-1].max_avail;
num_stripes = ndevs * dev_stripes;
- if (stripe_size * num_stripes > max_chunk_size * ncopies) {
+ if (stripe_size * ndevs > max_chunk_size * ncopies) {
stripe_size = max_chunk_size * ncopies;
- do_div(stripe_size, num_stripes);
+ do_div(stripe_size, ndevs);
}
do_div(stripe_size, dev_stripes);
+
+ /* align to BTRFS_STRIPE_LEN */
do_div(stripe_size, BTRFS_STRIPE_LEN);
stripe_size *= BTRFS_STRIPE_LEN;