By maintaining the device order consistency it makes reproducing the problems related to missing chunk in the degraded mode much more consistent. So fix this by sorting the devices by devid within the kernel. So that we know which device is assigned to the struct fs_info::latest_bdev when all the devices are having and same SB generation.
Signed-off-by: Anand Jain <anand.j...@oracle.com> --- fs/btrfs/volumes.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index b5036bd69e6a..0109f370ad5b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -27,6 +27,7 @@ #include <linux/raid/pq.h> #include <linux/semaphore.h> #include <linux/uuid.h> +#include <linux/list_sort.h> #include <asm/div64.h> #include "ctree.h" #include "extent_map.h" @@ -1102,6 +1103,20 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices, return ret; } +static int device_cmp(void *priv, struct list_head *a, struct list_head *b) +{ + struct btrfs_device *dev1, *dev2; + + dev1 = list_entry(a, struct btrfs_device, dev_list); + dev2 = list_entry(b, struct btrfs_device, dev_list); + + if (dev1->devid < dev2->devid) + return -1; + else if (dev1->devid > dev2->devid) + return 1; + return 0; +} + int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, fmode_t flags, void *holder) { @@ -1112,6 +1127,7 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices, fs_devices->opened++; ret = 0; } else { + list_sort(NULL, &fs_devices->devices, device_cmp); ret = __btrfs_open_devices(fs_devices, flags, holder); } mutex_unlock(&uuid_mutex); -- 2.7.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html