Btrfs: Write out all super blocks on commit, and bring back proper barrier support

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 3b927f698320..07d43553141c 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -125,6 +125,7 @@ static int device_list_add(const char *path,
                         return -ENOMEM;
                 }
                 device->devid = devid;
+                device->barriers = 1;
                 device->name = kstrdup(path, GFP_NOFS);
                 if (!device->name) {
                         kfree(device);
@@ -208,6 +209,7 @@ int btrfs_scan_one_device(const char *path, int flags, void *holder,
         struct buffer_head *bh;
         int ret;
         u64 devid;
+        u64 transid;
 
         mutex_lock(&uuid_mutex);
 
@@ -236,14 +238,14 @@ int btrfs_scan_one_device(const char *path, int flags, void *holder,
                 goto error_brelse;
         }
         devid = le64_to_cpu(disk_super->dev_item.devid);
-        printk("found device %Lu on %s\n", devid, path);
+        transid = btrfs_super_generation(disk_super);
+        printk("found device %Lu transid %Lu on %s\n", devid, transid, path);
         ret = device_list_add(path, disk_super, devid, fs_devices_ret);
 
 error_brelse:
         brelse(bh);
 error_close:
         close_bdev_excl(bdev);
-        printk("scan one closes bdev %s\n", path);
 error:
         mutex_unlock(&uuid_mutex);
         return ret;
@@ -1143,7 +1145,7 @@ static int read_one_dev(struct btrfs_root *root,
         device = btrfs_find_device(root, devid);
         if (!device) {
                 printk("warning devid %Lu not found already\n", devid);
-                device = kmalloc(sizeof(*device), GFP_NOFS);
+                device = kzalloc(sizeof(*device), GFP_NOFS);
                 if (!device)
                         return -ENOMEM;
                 list_add(&device->dev_list,