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 <miaox@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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 @@
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 @@
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 @@
return -ENOSPC;
num_stripes &= ~(u32)1;
sub_stripes = 2;
+ ncopies = 2;
min_stripes = 4;
}
@@ -2239,8 +2243,8 @@
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 @@
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);
