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

Pull block updates from Jens Axboe:
 "This is a bit bigger than it should be, but I could (did) not want to
  send it off last week due to both wanting extra testing, and expecting
  a fix for the bounce regression as well.  In any case, this contains:

   - Fix for the blk-merge.c compilation warning on gcc 5.x from me.

   - A set of back/front SG gap merge fixes, from me and from Sagi.
     This ensures that we honor SG gapping for integrity payloads as
     well.

   - Two small fixes for null_blk from Matias, fixing a leak and a
     capacity propagation issue.

   - A blkcg fix from Tejun, fixing a NULL dereference.

   - A fast clone optimization from Ming, fixing a performance
     regression since the arbitrarily sized bio's were introduced.

   - Also from Ming, a regression fix for bouncing IOs"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix bounce_end_io
  block: blk-merge: fast-clone bio when splitting rw bios
  block: blkg_destroy_all() should clear q->root_blkg and ->root_rl.blkg
  block: Copy a user iovec if it includes gaps
  block: Refuse adding appending a gapped integrity page to a bio
  block: Refuse request/bio merges with gaps in the integrity payload
  block: Check for gaps on front and back merges
  null_blk: fix wrong capacity when bs is not 512 bytes
  null_blk: fix memory leak on cleanup
  block: fix bogus compiler warnings in blk-merge.c

6 files changed, 61 insertions, 39 deletions

diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 4aecca79374ad..14b8faf8b09d4 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -140,6 +140,11 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
 
 	iv = bip->bip_vec + bip->bip_vcnt;
 
+	if (bip->bip_vcnt &&
+	    bvec_gap_to_prev(bdev_get_queue(bio->bi_bdev),
+			     &bip->bip_vec[bip->bip_vcnt - 1], offset))
+		return 0;
+
 	iv->bv_page = page;
 	iv->bv_len = len;
 	iv->bv_offset = offset;
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index ac8370cb25157..55512dd626336 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -370,6 +370,9 @@ static void blkg_destroy_all(struct request_queue *q)
 		blkg_destroy(blkg);
 		spin_unlock(&blkcg->lock);
 	}
+
+	q->root_blkg = NULL;
+	q->root_rl.blkg = NULL;
 }
 
 /*
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index f548b64be0924..75f29cf701889 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -204,6 +204,9 @@ bool blk_integrity_merge_rq(struct request_queue *q, struct request *req,
 	    q->limits.max_integrity_segments)
 		return false;
 
+	if (integrity_req_gap_back_merge(req, next->bio))
+		return false;
+
 	return true;
 }
 EXPORT_SYMBOL(blk_integrity_merge_rq);
diff --git a/block/blk-map.c b/block/blk-map.c
index 233841644c9d3..f565e11f465aa 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -9,6 +9,24 @@
 
 #include "blk.h"
 
+static bool iovec_gap_to_prv(struct request_queue *q,
+			     struct iovec *prv, struct iovec *cur)
+{
+	unsigned long prev_end;
+
+	if (!queue_virt_boundary(q))
+		return false;
+
+	if (prv->iov_base == NULL && prv->iov_len == 0)
+		/* prv is not set - don't check */
+		return false;
+
+	prev_end = (unsigned long)(prv->iov_base + prv->iov_len);
+
+	return (((unsigned long)cur->iov_base & queue_virt_boundary(q)) ||
+		prev_end & queue_virt_boundary(q));
+}
+
 int blk_rq_append_bio(struct request_queue *q, struct request *rq,
 		      struct bio *bio)
 {
@@ -67,7 +85,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 	struct bio *bio;
 	int unaligned = 0;
 	struct iov_iter i;
-	struct iovec iov;
+	struct iovec iov, prv = {.iov_base = NULL, .iov_len = 0};
 
 	if (!iter || !iter->count)
 		return -EINVAL;
@@ -81,8 +99,12 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 		/*
 		 * Keep going so we check length of all segments
 		 */
-		if (uaddr & queue_dma_alignment(q))
+		if ((uaddr & queue_dma_alignment(q)) ||
+		    iovec_gap_to_prv(q, &prv, &iov))
 			unaligned = 1;
+
+		prv.iov_base = iov.iov_base;
+		prv.iov_len = iov.iov_len;
 	}
 
 	if (unaligned || (q->dma_pad_mask & iter->count) || map_data)
diff --git a/block/blk-merge.c b/block/blk-merge.c
index d088cffb81050..c4e9c37f3e381 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -66,36 +66,33 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
 					 struct bio *bio,
 					 struct bio_set *bs)
 {
-	struct bio *split;
-	struct bio_vec bv, bvprv;
+	struct bio_vec bv, bvprv, *bvprvp = NULL;
 	struct bvec_iter iter;
 	unsigned seg_size = 0, nsegs = 0, sectors = 0;
-	int prev = 0;
 
 	bio_for_each_segment(bv, bio, iter) {
-		sectors += bv.bv_len >> 9;
-
-		if (sectors > queue_max_sectors(q))
+		if (sectors + (bv.bv_len >> 9) > queue_max_sectors(q))
 			goto split;
 
 		/*
 		 * If the queue doesn't support SG gaps and adding this
 		 * offset would create a gap, disallow it.
 		 */
-		if (prev && bvec_gap_to_prev(q, &bvprv, bv.bv_offset))
+		if (bvprvp && bvec_gap_to_prev(q, bvprvp, bv.bv_offset))
 			goto split;
 
-		if (prev && blk_queue_cluster(q)) {
+		if (bvprvp && blk_queue_cluster(q)) {
 			if (seg_size + bv.bv_len > queue_max_segment_size(q))
 				goto new_segment;
-			if (!BIOVEC_PHYS_MERGEABLE(&bvprv, &bv))
+			if (!BIOVEC_PHYS_MERGEABLE(bvprvp, &bv))
 				goto new_segment;
-			if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv))
+			if (!BIOVEC_SEG_BOUNDARY(q, bvprvp, &bv))
 				goto new_segment;
 
 			seg_size += bv.bv_len;
 			bvprv = bv;
-			prev = 1;
+			bvprvp = &bv;
+			sectors += bv.bv_len >> 9;
 			continue;
 		}
 new_segment:
@@ -104,23 +101,14 @@ new_segment:
 
 		nsegs++;
 		bvprv = bv;
-		prev = 1;
+		bvprvp = &bv;
 		seg_size = bv.bv_len;
+		sectors += bv.bv_len >> 9;
 	}
 
 	return NULL;
 split:
-	split = bio_clone_bioset(bio, GFP_NOIO, bs);
-
-	split->bi_iter.bi_size -= iter.bi_size;
-	bio->bi_iter = iter;
-
-	if (bio_integrity(bio)) {
-		bio_integrity_advance(bio, split->bi_iter.bi_size);
-		bio_integrity_trim(split, 0, bio_sectors(split));
-	}
-
-	return split;
+	return bio_split(bio, sectors, GFP_NOIO, bs);
 }
 
 void blk_queue_split(struct request_queue *q, struct bio **bio,
@@ -439,6 +427,11 @@ no_merge:
 int ll_back_merge_fn(struct request_queue *q, struct request *req,
 		     struct bio *bio)
 {
+	if (req_gap_back_merge(req, bio))
+		return 0;
+	if (blk_integrity_rq(req) &&
+	    integrity_req_gap_back_merge(req, bio))
+		return 0;
 	if (blk_rq_sectors(req) + bio_sectors(bio) >
 	    blk_rq_get_max_sectors(req)) {
 		req->cmd_flags |= REQ_NOMERGE;
@@ -457,6 +450,12 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req,
 int ll_front_merge_fn(struct request_queue *q, struct request *req,
 		      struct bio *bio)
 {
+
+	if (req_gap_front_merge(req, bio))
+		return 0;
+	if (blk_integrity_rq(req) &&
+	    integrity_req_gap_front_merge(req, bio))
+		return 0;
 	if (blk_rq_sectors(req) + bio_sectors(bio) >
 	    blk_rq_get_max_sectors(req)) {
 		req->cmd_flags |= REQ_NOMERGE;
@@ -483,14 +482,6 @@ static bool req_no_special_merge(struct request *req)
 	return !q->mq_ops && req->special;
 }
 
-static int req_gap_to_prev(struct request *req, struct bio *next)
-{
-	struct bio *prev = req->biotail;
-
-	return bvec_gap_to_prev(req->q, &prev->bi_io_vec[prev->bi_vcnt - 1],
-			next->bi_io_vec[0].bv_offset);
-}
-
 static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
 				struct request *next)
 {
@@ -505,7 +496,7 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
 	if (req_no_special_merge(req) || req_no_special_merge(next))
 		return 0;
 
-	if (req_gap_to_prev(req, next->bio))
+	if (req_gap_back_merge(req, next->bio))
 		return 0;
 
 	/*
@@ -713,10 +704,6 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
 	    !blk_write_same_mergeable(rq->bio, bio))
 		return false;
 
-	/* Only check gaps if the bio carries data */
-	if (bio_has_data(bio) && req_gap_to_prev(rq, bio))
-		return false;
-
 	return true;
 }
 
diff --git a/block/bounce.c b/block/bounce.c
index 0611aea1cfe9f..1cb5dd3a5da1e 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -128,12 +128,14 @@ static void bounce_end_io(struct bio *bio, mempool_t *pool)
 	struct bio *bio_orig = bio->bi_private;
 	struct bio_vec *bvec, *org_vec;
 	int i;
+	int start = bio_orig->bi_iter.bi_idx;
 
 	/*
 	 * free up bounce indirect pages used
 	 */
 	bio_for_each_segment_all(bvec, bio, i) {
-		org_vec = bio_orig->bi_io_vec + i;
+		org_vec = bio_orig->bi_io_vec + i + start;
+
 		if (bvec->bv_page == org_vec->bv_page)
 			continue;