Merge tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "Highlights:

   - speedup dead root detection during orphan cleanup, eg. when there
     are many deleted subvolumes waiting to be cleaned, the trees are
     now looked up in radix tree instead of a O(N^2) search

   - snapshot creation with inherited qgroup will mark the qgroup
     inconsistent, requires a rescan

   - send will emit file capabilities after chown, this produces a
     stream that does not need postprocessing to set the capabilities
     again

   - direct io ported to iomap infrastructure, cleaned up and simplified
     code, notably removing last use of struct buffer_head in btrfs code

  Core changes:

   - factor out backreference iteration, to be used by ordinary
     backreferences and relocation code

   - improved global block reserve utilization
      * better logic to serialize requests
      * increased maximum available for unlink
      * improved handling on large pages (64K)

   - direct io cleanups and fixes
      * simplify layering, where cloned bios were unnecessarily created
        for some cases
      * error handling fixes (submit, endio)
      * remove repair worker thread, used to avoid deadlocks during
        repair

   - refactored block group reading code, preparatory work for new type
     of block group storage that should improve mount time on large
     filesystems

  Cleanups:

   - cleaned up (and slightly sped up) set/get helpers for metadata data
     structure members

   - root bit REF_COWS got renamed to SHAREABLE to reflect the that the
     blocks of the tree get shared either among subvolumes or with the
     relocation trees

  Fixes:

   - when subvolume deletion fails due to ENOSPC, the filesystem is not
     turned read-only

   - device scan deals with devices from other filesystems that changed
     ownership due to overwrite (mkfs)

   - fix a race between scrub and block group removal/allocation

   - fix long standing bug of a runaway balance operation, printing the
     same line to the syslog, caused by a stale status bit on a reloc
     tree that prevented progress

   - fix corrupt log due to concurrent fsync of inodes with shared
     extents

   - fix space underflow for NODATACOW and buffered writes when it for
     some reason needs to fallback to COW mode"

* tag 'for-5.8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (133 commits)
  btrfs: fix space_info bytes_may_use underflow during space cache writeout
  btrfs: fix space_info bytes_may_use underflow after nocow buffered write
  btrfs: fix wrong file range cleanup after an error filling dealloc range
  btrfs: remove redundant local variable in read_block_for_search
  btrfs: open code key_search
  btrfs: split btrfs_direct_IO to read and write part
  btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK
  fs: remove dio_end_io()
  btrfs: switch to iomap_dio_rw() for dio
  iomap: remove lockdep_assert_held()
  iomap: add a filesystem hook for direct I/O bio submission
  fs: export generic_file_buffered_read()
  btrfs: turn space cache writeout failure messages into debug messages
  btrfs: include error on messages about failure to write space/inode caches
  btrfs: remove useless 'fail_unlock' label from btrfs_csum_file_blocks()
  btrfs: do not ignore error from btrfs_next_leaf() when inserting checksums
  btrfs: make checksum item extension more efficient
  btrfs: fix corrupt log due to concurrent fsync of inodes with shared extents
  btrfs: unexport btrfs_compress_set_level()
  btrfs: simplify iget helpers
  ...

1 files changed, 44 insertions, 36 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c1909e5f4506..0d6e785bcb98 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -280,10 +280,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info,
  * ============
  *
  * uuid_mutex
- *   volume_mutex
- *     device_list_mutex
- *       chunk_mutex
- *     balance_mutex
+ *   device_list_mutex
+ *     chunk_mutex
+ *   balance_mutex
  *
  *
  * Exclusive operations, BTRFS_FS_EXCL_OP
@@ -1042,6 +1041,8 @@ again:
 							&device->dev_state)) {
 			if (!test_bit(BTRFS_DEV_STATE_REPLACE_TGT,
 			     &device->dev_state) &&
+			    !test_bit(BTRFS_DEV_STATE_MISSING,
+				      &device->dev_state) &&
 			     (!latest_dev ||
 			      device->generation > latest_dev->generation)) {
 				latest_dev = device;
@@ -1185,7 +1186,6 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
 {
 	struct btrfs_device *device;
 	struct btrfs_device *latest_dev = NULL;
-	int ret = 0;
 
 	flags |= FMODE_EXCL;
 
@@ -1198,16 +1198,15 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices,
 		    device->generation > latest_dev->generation)
 			latest_dev = device;
 	}
-	if (fs_devices->open_devices == 0) {
-		ret = -EINVAL;
-		goto out;
-	}
+	if (fs_devices->open_devices == 0)
+		return -EINVAL;
+
 	fs_devices->opened = 1;
 	fs_devices->latest_bdev = latest_dev->bdev;
 	fs_devices->total_rw_bytes = 0;
 	fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_REGULAR;
-out:
-	return ret;
+
+	return 0;
 }
 
 static int devid_cmp(void *priv, struct list_head *a, struct list_head *b)
@@ -1251,49 +1250,48 @@ void btrfs_release_disk_super(struct btrfs_super_block *super)
 	put_page(page);
 }
 
-static int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr,
-				 struct page **page,
-				 struct btrfs_super_block **disk_super)
+static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev,
+						       u64 bytenr)
 {
+	struct btrfs_super_block *disk_super;
+	struct page *page;
 	void *p;
 	pgoff_t index;
 
 	/* make sure our super fits in the device */
 	if (bytenr + PAGE_SIZE >= i_size_read(bdev->bd_inode))
-		return 1;
+		return ERR_PTR(-EINVAL);
 
 	/* make sure our super fits in the page */
-	if (sizeof(**disk_super) > PAGE_SIZE)
-		return 1;
+	if (sizeof(*disk_super) > PAGE_SIZE)
+		return ERR_PTR(-EINVAL);
 
 	/* make sure our super doesn't straddle pages on disk */
 	index = bytenr >> PAGE_SHIFT;
-	if ((bytenr + sizeof(**disk_super) - 1) >> PAGE_SHIFT != index)
-		return 1;
+	if ((bytenr + sizeof(*disk_super) - 1) >> PAGE_SHIFT != index)
+		return ERR_PTR(-EINVAL);
 
 	/* pull in the page with our super */
-	*page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
-				   index, GFP_KERNEL);
+	page = read_cache_page_gfp(bdev->bd_inode->i_mapping, index, GFP_KERNEL);
 
-	if (IS_ERR(*page))
-		return 1;
+	if (IS_ERR(page))
+		return ERR_CAST(page);
 
-	p = page_address(*page);
+	p = page_address(page);
 
 	/* align our pointer to the offset of the super block */
-	*disk_super = p + offset_in_page(bytenr);
+	disk_super = p + offset_in_page(bytenr);
 
-	if (btrfs_super_bytenr(*disk_super) != bytenr ||
-	    btrfs_super_magic(*disk_super) != BTRFS_MAGIC) {
+	if (btrfs_super_bytenr(disk_super) != bytenr ||
+	    btrfs_super_magic(disk_super) != BTRFS_MAGIC) {
 		btrfs_release_disk_super(p);
-		return 1;
+		return ERR_PTR(-EINVAL);
 	}
 
-	if ((*disk_super)->label[0] &&
-		(*disk_super)->label[BTRFS_LABEL_SIZE - 1])
-		(*disk_super)->label[BTRFS_LABEL_SIZE - 1] = '\0';
+	if (disk_super->label[0] && disk_super->label[BTRFS_LABEL_SIZE - 1])
+		disk_super->label[BTRFS_LABEL_SIZE - 1] = 0;
 
-	return 0;
+	return disk_super;
 }
 
 int btrfs_forget_devices(const char *path)
@@ -1319,7 +1317,6 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
 	bool new_device_added = false;
 	struct btrfs_device *device = NULL;
 	struct block_device *bdev;
-	struct page *page;
 	u64 bytenr;
 
 	lockdep_assert_held(&uuid_mutex);
@@ -1337,8 +1334,9 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
 
-	if (btrfs_read_disk_super(bdev, bytenr, &page, &disk_super)) {
-		device = ERR_PTR(-EINVAL);
+	disk_super = btrfs_read_disk_super(bdev, bytenr);
+	if (IS_ERR(disk_super)) {
+		device = ERR_CAST(disk_super);
 		goto error_bdev_put;
 	}
 
@@ -2663,8 +2661,18 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 		ret = btrfs_commit_transaction(trans);
 	}
 
-	/* Update ctime/mtime for libblkid */
+	/*
+	 * Now that we have written a new super block to this device, check all
+	 * other fs_devices list if device_path alienates any other scanned
+	 * device.
+	 * We can ignore the return value as it typically returns -EINVAL and
+	 * only succeeds if the device was an alien.
+	 */
+	btrfs_forget_devices(device_path);
+
+	/* Update ctime/mtime for blkid or udev */
 	update_dev_time(device_path);
+
 	return ret;
 
 error_sysfs: