Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-block

Pull core block updates from Jens Axboe:
 "This first core part of the block IO changes contains:

   - Cleanup of the bio IO error signaling from Christoph.  We used to
     rely on the uptodate bit and passing around of an error, now we
     store the error in the bio itself.

   - Improvement of the above from myself, by shrinking the bio size
     down again to fit in two cachelines on x86-64.

   - Revert of the max_hw_sectors cap removal from a revision again,
     from Jeff Moyer.  This caused performance regressions in various
     tests.  Reinstate the limit, bump it to a more reasonable size
     instead.

   - Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me.
     Most devices have huge trim limits, which can cause nasty latencies
     when deleting files.  Enable the admin to configure the size down.
     We will look into having a more sane default instead of UINT_MAX
     sectors.

   - Improvement of the SGP gaps logic from Keith Busch.

   - Enable the block core to handle arbitrarily sized bios, which
     enables a nice simplification of bio_add_page() (which is an IO hot
     path).  From Kent.

   - Improvements to the partition io stats accounting, making it
     faster.  From Ming Lei.

   - Also from Ming Lei, a basic fixup for overflow of the sysfs pending
     file in blk-mq, as well as a fix for a blk-mq timeout race
     condition.

   - Ming Lin has been carrying Kents above mentioned patches forward
     for a while, and testing them.  Ming also did a few fixes around
     that.

   - Sasha Levin found and fixed a use-after-free problem introduced by
     the bio->bi_error changes from Christoph.

   - Small blk cgroup cleanup from Viresh Kumar"

* 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits)
  blk: Fix bio_io_vec index when checking bvec gaps
  block: Replace SG_GAPS with new queue limits mask
  block: bump BLK_DEF_MAX_SECTORS to 2560
  Revert "block: remove artifical max_hw_sectors cap"
  blk-mq: fix race between timeout and freeing request
  blk-mq: fix buffer overflow when reading sysfs file of 'pending'
  Documentation: update notes in biovecs about arbitrarily sized bios
  block: remove bio_get_nr_vecs()
  fs: use helper bio_add_page() instead of open coding on bi_io_vec
  block: kill merge_bvec_fn() completely
  md/raid5: get rid of bio_fits_rdev()
  md/raid5: split bio for chunk_aligned_read
  block: remove split code in blkdev_issue_{discard,write_same}
  btrfs: remove bio splitting and merge_bvec_fn() calls
  bcache: remove driver private bio splitting code
  block: simplify bio_add_page()
  block: make generic_make_request handle arbitrarily sized bios
  blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL)
  block: don't access bio->bi_error after bio_put()
  block: shrink struct bio down to 2 cache lines again
  ...

1 files changed, 28 insertions, 34 deletions

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index fa72068bd256..0a02e24900aa 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -851,7 +851,7 @@ static void free_raid_bio(struct btrfs_raid_bio *rbio)
  * this frees the rbio and runs through all the bios in the
  * bio_list and calls end_io on them
  */
-static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, int err, int uptodate)
+static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, int err)
 {
 	struct bio *cur = bio_list_get(&rbio->bio_list);
 	struct bio *next;
@@ -864,9 +864,8 @@ static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, int err, int uptodate)
 	while (cur) {
 		next = cur->bi_next;
 		cur->bi_next = NULL;
-		if (uptodate)
-			set_bit(BIO_UPTODATE, &cur->bi_flags);
-		bio_endio(cur, err);
+		cur->bi_error = err;
+		bio_endio(cur);
 		cur = next;
 	}
 }
@@ -875,9 +874,10 @@ static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, int err, int uptodate)
  * end io function used by finish_rmw.  When we finally
  * get here, we've written a full stripe
  */
-static void raid_write_end_io(struct bio *bio, int err)
+static void raid_write_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
+	int err = bio->bi_error;
 
 	if (err)
 		fail_bio_stripe(rbio, bio);
@@ -893,7 +893,7 @@ static void raid_write_end_io(struct bio *bio, int err)
 	if (atomic_read(&rbio->error) > rbio->bbio->max_errors)
 		err = -EIO;
 
-	rbio_orig_end_io(rbio, err, 0);
+	rbio_orig_end_io(rbio, err);
 	return;
 }
 
@@ -1071,7 +1071,7 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio,
 		 * devices or if they are not contiguous
 		 */
 		if (last_end == disk_start && stripe->dev->bdev &&
-		    test_bit(BIO_UPTODATE, &last->bi_flags) &&
+		    !last->bi_error &&
 		    last->bi_bdev == stripe->dev->bdev) {
 			ret = bio_add_page(last, page, PAGE_CACHE_SIZE, 0);
 			if (ret == PAGE_CACHE_SIZE)
@@ -1087,7 +1087,6 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio,
 	bio->bi_iter.bi_size = 0;
 	bio->bi_bdev = stripe->dev->bdev;
 	bio->bi_iter.bi_sector = disk_start >> 9;
-	set_bit(BIO_UPTODATE, &bio->bi_flags);
 
 	bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
 	bio_list_add(bio_list, bio);
@@ -1312,13 +1311,12 @@ write_data:
 
 		bio->bi_private = rbio;
 		bio->bi_end_io = raid_write_end_io;
-		BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags));
 		submit_bio(WRITE, bio);
 	}
 	return;
 
 cleanup:
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 }
 
 /*
@@ -1441,11 +1439,11 @@ static void set_bio_pages_uptodate(struct bio *bio)
  * This will usually kick off finish_rmw once all the bios are read in, but it
  * may trigger parity reconstruction if we had any errors along the way
  */
-static void raid_rmw_end_io(struct bio *bio, int err)
+static void raid_rmw_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
 
-	if (err)
+	if (bio->bi_error)
 		fail_bio_stripe(rbio, bio);
 	else
 		set_bio_pages_uptodate(bio);
@@ -1455,7 +1453,6 @@ static void raid_rmw_end_io(struct bio *bio, int err)
 	if (!atomic_dec_and_test(&rbio->stripes_pending))
 		return;
 
-	err = 0;
 	if (atomic_read(&rbio->error) > rbio->bbio->max_errors)
 		goto cleanup;
 
@@ -1469,7 +1466,7 @@ static void raid_rmw_end_io(struct bio *bio, int err)
 
 cleanup:
 
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 }
 
 static void async_rmw_stripe(struct btrfs_raid_bio *rbio)
@@ -1572,14 +1569,13 @@ static int raid56_rmw_stripe(struct btrfs_raid_bio *rbio)
 		btrfs_bio_wq_end_io(rbio->fs_info, bio,
 				    BTRFS_WQ_ENDIO_RAID56);
 
-		BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags));
 		submit_bio(READ, bio);
 	}
 	/* the actual write will happen once the reads are done */
 	return 0;
 
 cleanup:
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 	return -EIO;
 
 finish:
@@ -1964,7 +1960,7 @@ cleanup_io:
 		else
 			clear_bit(RBIO_CACHE_READY_BIT, &rbio->flags);
 
-		rbio_orig_end_io(rbio, err, err == 0);
+		rbio_orig_end_io(rbio, err);
 	} else if (err == 0) {
 		rbio->faila = -1;
 		rbio->failb = -1;
@@ -1976,7 +1972,7 @@ cleanup_io:
 		else
 			BUG();
 	} else {
-		rbio_orig_end_io(rbio, err, 0);
+		rbio_orig_end_io(rbio, err);
 	}
 }
 
@@ -1984,7 +1980,7 @@ cleanup_io:
  * This is called only for stripes we've read from disk to
  * reconstruct the parity.
  */
-static void raid_recover_end_io(struct bio *bio, int err)
+static void raid_recover_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
 
@@ -1992,7 +1988,7 @@ static void raid_recover_end_io(struct bio *bio, int err)
 	 * we only read stripe pages off the disk, set them
 	 * up to date if there were no errors
 	 */
-	if (err)
+	if (bio->bi_error)
 		fail_bio_stripe(rbio, bio);
 	else
 		set_bio_pages_uptodate(bio);
@@ -2002,7 +1998,7 @@ static void raid_recover_end_io(struct bio *bio, int err)
 		return;
 
 	if (atomic_read(&rbio->error) > rbio->bbio->max_errors)
-		rbio_orig_end_io(rbio, -EIO, 0);
+		rbio_orig_end_io(rbio, -EIO);
 	else
 		__raid_recover_end_io(rbio);
 }
@@ -2094,7 +2090,6 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio)
 		btrfs_bio_wq_end_io(rbio->fs_info, bio,
 				    BTRFS_WQ_ENDIO_RAID56);
 
-		BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags));
 		submit_bio(READ, bio);
 	}
 out:
@@ -2102,7 +2097,7 @@ out:
 
 cleanup:
 	if (rbio->operation == BTRFS_RBIO_READ_REBUILD)
-		rbio_orig_end_io(rbio, -EIO, 0);
+		rbio_orig_end_io(rbio, -EIO);
 	return -EIO;
 }
 
@@ -2277,11 +2272,12 @@ static int alloc_rbio_essential_pages(struct btrfs_raid_bio *rbio)
  * end io function used by finish_rmw.  When we finally
  * get here, we've written a full stripe
  */
-static void raid_write_parity_end_io(struct bio *bio, int err)
+static void raid_write_parity_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
+	int err = bio->bi_error;
 
-	if (err)
+	if (bio->bi_error)
 		fail_bio_stripe(rbio, bio);
 
 	bio_put(bio);
@@ -2294,7 +2290,7 @@ static void raid_write_parity_end_io(struct bio *bio, int err)
 	if (atomic_read(&rbio->error))
 		err = -EIO;
 
-	rbio_orig_end_io(rbio, err, 0);
+	rbio_orig_end_io(rbio, err);
 }
 
 static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
@@ -2437,7 +2433,7 @@ submit_write:
 	nr_data = bio_list_size(&bio_list);
 	if (!nr_data) {
 		/* Every parity is right */
-		rbio_orig_end_io(rbio, 0, 0);
+		rbio_orig_end_io(rbio, 0);
 		return;
 	}
 
@@ -2450,13 +2446,12 @@ submit_write:
 
 		bio->bi_private = rbio;
 		bio->bi_end_io = raid_write_parity_end_io;
-		BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags));
 		submit_bio(WRITE, bio);
 	}
 	return;
 
 cleanup:
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 }
 
 static inline int is_data_stripe(struct btrfs_raid_bio *rbio, int stripe)
@@ -2524,7 +2519,7 @@ static void validate_rbio_for_parity_scrub(struct btrfs_raid_bio *rbio)
 	return;
 
 cleanup:
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 }
 
 /*
@@ -2535,11 +2530,11 @@ cleanup:
  * This will usually kick off finish_rmw once all the bios are read in, but it
  * may trigger parity reconstruction if we had any errors along the way
  */
-static void raid56_parity_scrub_end_io(struct bio *bio, int err)
+static void raid56_parity_scrub_end_io(struct bio *bio)
 {
 	struct btrfs_raid_bio *rbio = bio->bi_private;
 
-	if (err)
+	if (bio->bi_error)
 		fail_bio_stripe(rbio, bio);
 	else
 		set_bio_pages_uptodate(bio);
@@ -2632,14 +2627,13 @@ static void raid56_parity_scrub_stripe(struct btrfs_raid_bio *rbio)
 		btrfs_bio_wq_end_io(rbio->fs_info, bio,
 				    BTRFS_WQ_ENDIO_RAID56);
 
-		BUG_ON(!test_bit(BIO_UPTODATE, &bio->bi_flags));
 		submit_bio(READ, bio);
 	}
 	/* the actual write will happen once the reads are done */
 	return;
 
 cleanup:
-	rbio_orig_end_io(rbio, -EIO, 0);
+	rbio_orig_end_io(rbio, -EIO);
 	return;
 
 finish: