From 1974a3b42d8cf7a9c74f1e0310c593023617037a Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Wed, 5 Jan 2011 10:07:24 +0000 Subject: [PATCH] btrfs: fix wrong calculation of stripe size There are two tiny problem: - One is When we check the chunk size is greater than the max chunk size or not, we should take mirrors into account, but the original code didn't. - The other is btrfs shouldn't use the size of the residual free space as the length of of a dup chunk when doing chunk allocation. It is because the device space that a dup chunk needs is twice as large as the chunk size, if we use the size of the residual free space as the length of a dup chunk, we can not get enough free space. Fix it. Signed-off-by: Miao Xie Reviewed-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/volumes.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 177b731..c50a85e 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -2177,6 +2177,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, int num_stripes = 1; int min_stripes = 1; int sub_stripes = 0; + int ncopies = 1; int looped = 0; int ret; int index; @@ -2197,12 +2198,14 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, if (type & (BTRFS_BLOCK_GROUP_DUP)) { num_stripes = 2; min_stripes = 2; + ncopies = 2; } if (type & (BTRFS_BLOCK_GROUP_RAID1)) { if (fs_devices->rw_devices < 2) return -ENOSPC; num_stripes = 2; min_stripes = 2; + ncopies = 2; } if (type & (BTRFS_BLOCK_GROUP_RAID10)) { num_stripes = fs_devices->rw_devices; @@ -2210,6 +2213,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, return -ENOSPC; num_stripes &= ~(u32)1; sub_stripes = 2; + ncopies = 2; min_stripes = 4; } @@ -2239,8 +2243,8 @@ again: map->num_stripes = num_stripes; } - if (calc_size * num_stripes > max_chunk_size) { - calc_size = max_chunk_size; + if (calc_size * num_stripes > max_chunk_size * ncopies) { + calc_size = max_chunk_size * ncopies; do_div(calc_size, num_stripes); do_div(calc_size, stripe_len); calc_size *= stripe_len; @@ -2321,6 +2325,8 @@ again: if (!looped && max_avail > 0) { looped = 1; calc_size = max_avail; + if (type & BTRFS_BLOCK_GROUP_DUP) + do_div(calc_size, 2); goto again; } kfree(map); -- 2.7.4