From 37db63a400d3bac467795aa43901065fd8d903b7 Mon Sep 17 00:00:00 2001
From: Ilya Dryomov <idryomov@gmail.com>
Date: Fri, 13 Apr 2012 17:05:08 +0300
Subject: [PATCH] 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>
---
fs/btrfs/volumes.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 759d02486d7c..ce289af526f0 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -3324,12 +3324,14 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
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;
--
2.50.1