Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs updates from Chris Mason:
 "This has Jeff Mahoney's long standing trim patch that fixes corners
  where trims were missing.  Omar has some raid5/6 fixes, especially for
  using scrub and device replace when devices are missing.

  Zhao Lie continues cleaning and fixing things, this series fixes some
  really hard to hit corners in xfstests.  I had to pull it last merge
  window due to some deadlocks, but those are now resolved.

  I added support for Tejun's new blkio controllers.  It seems to work
  well for single devices, we'll expand to multi-device as well"

* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (47 commits)
  btrfs: fix compile when block cgroups are not enabled
  Btrfs: fix file read corruption after extent cloning and fsync
  Btrfs: check if previous transaction aborted to avoid fs corruption
  btrfs: use __GFP_NOFAIL in alloc_btrfs_bio
  btrfs: Prevent from early transaction abort
  btrfs: Remove unused arguments in tree-log.c
  btrfs: Remove useless condition in start_log_trans()
  Btrfs: add support for blkio controllers
  Btrfs: remove unused mutex from struct 'btrfs_fs_info'
  Btrfs: fix parity scrub of RAID 5/6 with missing device
  Btrfs: fix device replace of a missing RAID 5/6 device
  Btrfs: add RAID 5/6 BTRFS_RBIO_REBUILD_MISSING operation
  Btrfs: count devices correctly in readahead during RAID 5/6 replace
  Btrfs: remove misleading handling of missing device scrub
  btrfs: fix clone / extent-same deadlocks
  Btrfs: fix defrag to merge tail file extent
  Btrfs: fix warning in backref walking
  btrfs: Add WARN_ON() for double lock in btrfs_tree_lock()
  btrfs: Remove root argument in extent_data_ref_count()
  btrfs: Fix wrong comment of btrfs_alloc_tree_block()
  ...

1 files changed, 77 insertions, 10 deletions

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 0a02e24900aa..fcf7265ca46f 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -61,9 +61,10 @@
 #define RBIO_CACHE_SIZE 1024
 
 enum btrfs_rbio_ops {
-	BTRFS_RBIO_WRITE	= 0,
-	BTRFS_RBIO_READ_REBUILD	= 1,
-	BTRFS_RBIO_PARITY_SCRUB	= 2,
+	BTRFS_RBIO_WRITE,
+	BTRFS_RBIO_READ_REBUILD,
+	BTRFS_RBIO_PARITY_SCRUB,
+	BTRFS_RBIO_REBUILD_MISSING,
 };
 
 struct btrfs_raid_bio {
@@ -602,6 +603,10 @@ static int rbio_can_merge(struct btrfs_raid_bio *last,
 	    cur->operation == BTRFS_RBIO_PARITY_SCRUB)
 		return 0;
 
+	if (last->operation == BTRFS_RBIO_REBUILD_MISSING ||
+	    cur->operation == BTRFS_RBIO_REBUILD_MISSING)
+		return 0;
+
 	return 1;
 }
 
@@ -793,7 +798,10 @@ static noinline void unlock_stripe(struct btrfs_raid_bio *rbio)
 
 			if (next->operation == BTRFS_RBIO_READ_REBUILD)
 				async_read_rebuild(next);
-			else if (next->operation == BTRFS_RBIO_WRITE) {
+			else if (next->operation == BTRFS_RBIO_REBUILD_MISSING) {
+				steal_rbio(rbio, next);
+				async_read_rebuild(next);
+			} else if (next->operation == BTRFS_RBIO_WRITE) {
 				steal_rbio(rbio, next);
 				async_rmw_stripe(next);
 			} else if (next->operation == BTRFS_RBIO_PARITY_SCRUB) {
@@ -1805,7 +1813,8 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio)
 	faila = rbio->faila;
 	failb = rbio->failb;
 
-	if (rbio->operation == BTRFS_RBIO_READ_REBUILD) {
+	if (rbio->operation == BTRFS_RBIO_READ_REBUILD ||
+	    rbio->operation == BTRFS_RBIO_REBUILD_MISSING) {
 		spin_lock_irq(&rbio->bio_list_lock);
 		set_bit(RBIO_RMW_LOCKED_BIT, &rbio->flags);
 		spin_unlock_irq(&rbio->bio_list_lock);
@@ -1830,7 +1839,8 @@ static void __raid_recover_end_io(struct btrfs_raid_bio *rbio)
 			 * if we're rebuilding a read, we have to use
 			 * pages from the bio list
 			 */
-			if (rbio->operation == BTRFS_RBIO_READ_REBUILD &&
+			if ((rbio->operation == BTRFS_RBIO_READ_REBUILD ||
+			     rbio->operation == BTRFS_RBIO_REBUILD_MISSING) &&
 			    (stripe == faila || stripe == failb)) {
 				page = page_in_rbio(rbio, stripe, pagenr, 0);
 			} else {
@@ -1939,7 +1949,8 @@ pstripe:
 			 * if we're rebuilding a read, we have to use
 			 * pages from the bio list
 			 */
-			if (rbio->operation == BTRFS_RBIO_READ_REBUILD &&
+			if ((rbio->operation == BTRFS_RBIO_READ_REBUILD ||
+			     rbio->operation == BTRFS_RBIO_REBUILD_MISSING) &&
 			    (stripe == faila || stripe == failb)) {
 				page = page_in_rbio(rbio, stripe, pagenr, 0);
 			} else {
@@ -1961,6 +1972,8 @@ cleanup_io:
 			clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags);
 
 		rbio_orig_end_io(rbio, err);
+	} else if (rbio->operation == BTRFS_RBIO_REBUILD_MISSING) {
+		rbio_orig_end_io(rbio, err);
 	} else if (err == 0) {
 		rbio->faila = -1;
 		rbio->failb = -1;
@@ -2096,7 +2109,8 @@ out:
 	return 0;
 
 cleanup:
-	if (rbio->operation == BTRFS_RBIO_READ_REBUILD)
+	if (rbio->operation == BTRFS_RBIO_READ_REBUILD ||
+	    rbio->operation == BTRFS_RBIO_REBUILD_MISSING)
 		rbio_orig_end_io(rbio, -EIO);
 	return -EIO;
 }
@@ -2227,8 +2241,9 @@ raid56_parity_alloc_scrub_rbio(struct btrfs_root *root, struct bio *bio,
 	return rbio;
 }
 
-void raid56_parity_add_scrub_pages(struct btrfs_raid_bio *rbio,
-				   struct page *page, u64 logical)
+/* Used for both parity scrub and missing. */
+void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page,
+			    u64 logical)
 {
 	int stripe_offset;
 	int index;
@@ -2662,3 +2677,55 @@ void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio)
 	if (!lock_stripe_add(rbio))
 		async_scrub_parity(rbio);
 }
+
+/* The following code is used for dev replace of a missing RAID 5/6 device. */
+
+struct btrfs_raid_bio *
+raid56_alloc_missing_rbio(struct btrfs_root *root, struct bio *bio,
+			  struct btrfs_bio *bbio, u64 length)
+{
+	struct btrfs_raid_bio *rbio;
+
+	rbio = alloc_rbio(root, bbio, length);
+	if (IS_ERR(rbio))
+		return NULL;
+
+	rbio->operation = BTRFS_RBIO_REBUILD_MISSING;
+	bio_list_add(&rbio->bio_list, bio);
+	/*
+	 * This is a special bio which is used to hold the completion handler
+	 * and make the scrub rbio is similar to the other types
+	 */
+	ASSERT(!bio->bi_iter.bi_size);
+
+	rbio->faila = find_logical_bio_stripe(rbio, bio);
+	if (rbio->faila == -1) {
+		BUG();
+		kfree(rbio);
+		return NULL;
+	}
+
+	return rbio;
+}
+
+static void missing_raid56_work(struct btrfs_work *work)
+{
+	struct btrfs_raid_bio *rbio;
+
+	rbio = container_of(work, struct btrfs_raid_bio, work);
+	__raid56_parity_recover(rbio);
+}
+
+static void async_missing_raid56(struct btrfs_raid_bio *rbio)
+{
+	btrfs_init_work(&rbio->work, btrfs_rmw_helper,
+			missing_raid56_work, NULL, NULL);
+
+	btrfs_queue_work(rbio->fs_info->rmw_workers, &rbio->work);
+}
+
+void raid56_submit_missing_rbio(struct btrfs_raid_bio *rbio)
+{
+	if (!lock_stripe_add(rbio))
+		async_missing_raid56(rbio);
+}