Merge branch 'anand/sysfs-updates-v4.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4

Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 47 insertions, 22 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 75f84e4c2033..7f934cccc98d 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2375,7 +2375,7 @@ static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
         /* returns with log_tree_root freed on success */
         ret = btrfs_recover_log_trees(log_tree_root);
         if (ret) {
-                btrfs_error(tree_root->fs_info, ret,
+                btrfs_std_error(tree_root->fs_info, ret,
                             "Failed to recover log tree");
                 free_extent_buffer(log_tree_root->node);
                 kfree(log_tree_root);
@@ -2651,8 +2651,8 @@ int open_ctree(struct super_block *sb,
          * Read super block and check the signature bytes only
          */
         bh = btrfs_read_dev_super(fs_devices->latest_bdev);
-        if (!bh) {
-                err = -EINVAL;
+        if (IS_ERR(bh)) {
+                err = PTR_ERR(bh);
                 goto fail_alloc;
         }
 
@@ -2935,7 +2935,7 @@ retry_root_backup:
                 goto fail_fsdev_sysfs;
         }
 
-        ret = btrfs_sysfs_add_one(fs_info);
+        ret = btrfs_sysfs_add_mounted(fs_info);
         if (ret) {
                 pr_err("BTRFS: failed to init sysfs interface: %d\n", ret);
                 goto fail_fsdev_sysfs;
@@ -3115,7 +3115,7 @@ fail_cleaner:
         filemap_write_and_wait(fs_info->btree_inode->i_mapping);
 
 fail_sysfs:
-        btrfs_sysfs_remove_one(fs_info);
+        btrfs_sysfs_remove_mounted(fs_info);
 
 fail_fsdev_sysfs:
         btrfs_sysfs_remove_fsid(fs_info->fs_devices);
@@ -3190,6 +3190,37 @@ static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
         put_bh(bh);
 }
 
+int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
+                        struct buffer_head **bh_ret)
+{
+        struct buffer_head *bh;
+        struct btrfs_super_block *super;
+        u64 bytenr;
+
+        bytenr = btrfs_sb_offset(copy_num);
+        if (bytenr + BTRFS_SUPER_INFO_SIZE >= i_size_read(bdev->bd_inode))
+                return -EINVAL;
+
+        bh = __bread(bdev, bytenr / 4096, BTRFS_SUPER_INFO_SIZE);
+        /*
+         * If we fail to read from the underlying devices, as of now
+         * the best option we have is to mark it EIO.
+         */
+        if (!bh)
+                return -EIO;
+
+        super = (struct btrfs_super_block *)bh->b_data;
+        if (btrfs_super_bytenr(super) != bytenr ||
+                    btrfs_super_magic(super) != BTRFS_MAGIC) {
+                brelse(bh);
+                return -EINVAL;
+        }
+
+        *bh_ret = bh;
+        return 0;
+}
+
+
 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
 {
         struct buffer_head *bh;
@@ -3197,7 +3228,7 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
         struct btrfs_super_block *super;
         int i;
         u64 transid = 0;
-        u64 bytenr;
+        int ret = -EINVAL;
 
         /* we would like to check all the supers, but that would make
          * a btrfs mount succeed after a mkfs from a different FS.
@@ -3205,21 +3236,11 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
          * later supers, using BTRFS_SUPER_MIRROR_MAX instead
          */
         for (i = 0; i < 1; i++) {
-                bytenr = btrfs_sb_offset(i);
-                if (bytenr + BTRFS_SUPER_INFO_SIZE >=
-                                        i_size_read(bdev->bd_inode))
-                        break;
-                bh = __bread(bdev, bytenr / 4096,
-                                        BTRFS_SUPER_INFO_SIZE);
-                if (!bh)
+                ret = btrfs_read_dev_one_super(bdev, i, &bh);
+                if (ret)
                         continue;
 
                 super = (struct btrfs_super_block *)bh->b_data;
-                if (btrfs_super_bytenr(super) != bytenr ||
-                    btrfs_super_magic(super) != BTRFS_MAGIC) {
-                        brelse(bh);
-                        continue;
-                }
 
                 if (!latest || btrfs_super_generation(super) > transid) {
                         brelse(latest);
@@ -3229,6 +3250,10 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
                         brelse(bh);
                 }
         }
+
+        if (!latest)
+                return ERR_PTR(ret);
+
         return latest;
 }
 
@@ -3547,7 +3572,7 @@ static int write_all_supers(struct btrfs_root *root, int max_mirrors)
                 if (ret) {
                         mutex_unlock(
                                 &root->fs_info->fs_devices->device_list_mutex);
-                        btrfs_error(root->fs_info, ret,
+                        btrfs_std_error(root->fs_info, ret,
                                     "errors while submitting device barriers.");
                         return ret;
                 }
@@ -3587,7 +3612,7 @@ static int write_all_supers(struct btrfs_root *root, int max_mirrors)
                 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
 
                 /* FUA is masked off if unsupported and can't be the reason */
-                btrfs_error(root->fs_info, -EIO,
+                btrfs_std_error(root->fs_info, -EIO,
                             "%d errors while writing supers", total_errors);
                 return -EIO;
         }
@@ -3605,7 +3630,7 @@ static int write_all_supers(struct btrfs_root *root, int max_mirrors)
         }
         mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
         if (total_errors > max_errors) {
-                btrfs_error(root->fs_info, -EIO,
+                btrfs_std_error(root->fs_info, -EIO,
                             "%d errors while writing supers", total_errors);
                 return -EIO;
         }
@@ -3791,7 +3816,7 @@ void close_ctree(struct btrfs_root *root)
                        percpu_counter_sum(&fs_info->delalloc_bytes));
         }
 
-        btrfs_sysfs_remove_one(fs_info);
+        btrfs_sysfs_remove_mounted(fs_info);
         btrfs_sysfs_remove_fsid(fs_info->fs_devices);
 
         btrfs_free_fs_roots(fs_info);