diff options
| -rw-r--r-- | fs/btrfs/super.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 96eb9fef7bd2..0eb9a4da069e 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -54,6 +54,7 @@ #include "version.h" #include "export.h" #include "compression.h" +#include "rcu-string.h" #define CREATE_TRACE_POINTS #include <trace/events/btrfs.h> @@ -1482,12 +1483,44 @@ static void btrfs_fs_dirty_inode(struct inode *inode, int flags) "error %d\n", btrfs_ino(inode), ret); } +static int btrfs_show_devname(struct seq_file *m, struct dentry *root) +{ + struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb); + struct btrfs_fs_devices *cur_devices; + struct btrfs_device *dev, *first_dev = NULL; + struct list_head *head; + struct rcu_string *name; + + mutex_lock(&fs_info->fs_devices->device_list_mutex); + cur_devices = fs_info->fs_devices; + while (cur_devices) { + head = &cur_devices->devices; + list_for_each_entry(dev, head, dev_list) { + if (!first_dev || dev->devid < first_dev->devid) + first_dev = dev; + } + cur_devices = cur_devices->seed; + } + + if (first_dev) { + rcu_read_lock(); + name = rcu_dereference(first_dev->name); + seq_escape(m, name->str, " \t\n\\"); + rcu_read_unlock(); + } else { + WARN_ON(1); + } + mutex_unlock(&fs_info->fs_devices->device_list_mutex); + return 0; +} + static const struct super_operations btrfs_super_ops = { .drop_inode = btrfs_drop_inode, .evict_inode = btrfs_evict_inode, .put_super = btrfs_put_super, .sync_fs = btrfs_sync_fs, .show_options = btrfs_show_options, + .show_devname = btrfs_show_devname, .write_inode = btrfs_write_inode, .dirty_inode = btrfs_fs_dirty_inode, .alloc_inode = btrfs_alloc_inode, |