btrfs: replace barriers with explicit flush / FUA usage

Switch to the WRITE_FLUSH_FUA flag for log writes, remove the EOPNOTSUPP
detection for barriers and stop setting the barrier flag for discards.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

1 files changed, 0 insertions, 4 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index dd318ff280b2..e25e46a8b4e2 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -398,7 +398,6 @@ static noinline int device_list_add(const char *path,
                 device->work.func = pending_bios_fn;
                 memcpy(device->uuid, disk_super->dev_item.uuid,
                        BTRFS_UUID_SIZE);
-                device->barriers = 1;
                 spin_lock_init(&device->io_lock);
                 device->name = kstrdup(path, GFP_NOFS);
                 if (!device->name) {
@@ -462,7 +461,6 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
                 device->devid = orig_dev->devid;
                 device->work.func = pending_bios_fn;
                 memcpy(device->uuid, orig_dev->uuid, sizeof(device->uuid));
-                device->barriers = 1;
                 spin_lock_init(&device->io_lock);
                 INIT_LIST_HEAD(&device->dev_list);
                 INIT_LIST_HEAD(&device->dev_alloc_list);
@@ -1489,7 +1487,6 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
         trans = btrfs_start_transaction(root, 0);
         lock_chunks(root);
 
-        device->barriers = 1;
         device->writeable = 1;
         device->work.func = pending_bios_fn;
         generate_random_uuid(device->uuid);
@@ -3084,7 +3081,6 @@ static struct btrfs_device *add_missing_dev(struct btrfs_root *root,
                 return NULL;
         list_add(&device->dev_list,
                  &fs_devices->devices);
-        device->barriers = 1;
         device->dev_root = root->fs_info->dev_root;
         device->devid = devid;
         device->work.func = pending_bios_fn;