Btrfs: Add support for device scanning and detection ioctls

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

1 files changed, 15 insertions, 9 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4890151cd68d..f971a29e4f20 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -365,12 +365,12 @@ static int close_all_devices(struct btrfs_fs_info *fs_info)
         struct list_head *next;
         struct btrfs_device *device;
 
-        list = &fs_info->devices;
-        while(!list_empty(list)) {
-                next = list->next;
-                list_del(next);
+        list = &fs_info->fs_devices->devices;
+        list_for_each(next, list) {
                 device = list_entry(next, struct btrfs_device, dev_list);
-                kfree(device);
+                if (device->bdev && device->bdev != fs_info->sb->s_bdev)
+                        close_bdev_excl(device->bdev);
+                device->bdev = NULL;
         }
         return 0;
 }
@@ -655,7 +655,8 @@ static int add_hasher(struct btrfs_fs_info *info, char *type) {
         return 0;
 }
 #endif
-struct btrfs_root *open_ctree(struct super_block *sb)
+struct btrfs_root *open_ctree(struct super_block *sb,
+                              struct btrfs_fs_devices *fs_devices)
 {
         u32 sectorsize;
         u32 nodesize;
@@ -697,8 +698,8 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         fs_info->extent_root = extent_root;
         fs_info->chunk_root = chunk_root;
         fs_info->dev_root = dev_root;
+        fs_info->fs_devices = fs_devices;
         INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots);
-        INIT_LIST_HEAD(&fs_info->devices);
         INIT_LIST_HEAD(&fs_info->space_info);
         btrfs_mapping_init(&fs_info->mapping_tree);
         fs_info->sb = sb;
@@ -779,6 +780,12 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         if (!btrfs_super_root(disk_super))
                 goto fail_sb_buffer;
 
+        if (btrfs_super_num_devices(disk_super) != fs_devices->num_devices) {
+                printk("Btrfs: wanted %llu devices, but found %llu\n",
+                       (unsigned long long)btrfs_super_num_devices(disk_super),
+                       (unsigned long long)fs_devices->num_devices);
+                goto fail_sb_buffer;
+        }
         nodesize = btrfs_super_nodesize(disk_super);
         leafsize = btrfs_super_leafsize(disk_super);
         sectorsize = btrfs_super_sectorsize(disk_super);
@@ -799,8 +806,6 @@ struct btrfs_root *open_ctree(struct super_block *sb)
         }
 
         mutex_lock(&fs_info->fs_mutex);
-        ret = btrfs_read_super_device(tree_root, fs_info->sb_buffer);
-        BUG_ON(ret);
 
         ret = btrfs_read_sys_array(tree_root);
         BUG_ON(ret);
@@ -859,6 +864,7 @@ fail_sb_buffer:
 fail_iput:
         iput(fs_info->btree_inode);
 fail:
+        close_all_devices(fs_info);
         kfree(extent_root);
         kfree(tree_root);
         kfree(fs_info);