block: manipulate bio->bi_flags through helpers

Some places use helpers now, others don't. We only have the 'is set'
helper, add helpers for setting and clearing flags too.

It was a bit of a mess of atomic vs non-atomic access. With
BIO_UPTODATE gone, we don't have any risk of concurrent access to the
flags. So relax the restriction and don't make any of them atomic. The
flags that do have serialization issues (reffed and chained), we
already handle those separately.

Signed-off-by: Jens Axboe <axboe@fb.com>

11 files changed, 33 insertions, 20 deletions

diff --git a/block/bio.c b/block/bio.c
index a23f489f398f..911ae8f82752 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -311,7 +311,7 @@ static void bio_chain_endio(struct bio *bio)
  */
 static inline void bio_inc_remaining(struct bio *bio)
 {
-	bio->bi_flags |= (1 << BIO_CHAIN);
+	bio_set_flag(bio, BIO_CHAIN);
 	smp_mb__before_atomic();
 	atomic_inc(&bio->__bi_remaining);
 }
@@ -495,7 +495,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
 		if (unlikely(!bvl))
 			goto err_free;
 
-		bio->bi_flags |= 1 << BIO_OWNS_VEC;
+		bio_set_flag(bio, BIO_OWNS_VEC);
 	} else if (nr_iovecs) {
 		bvl = bio->bi_inline_vecs;
 	}
@@ -580,7 +580,7 @@ void __bio_clone_fast(struct bio *bio, struct bio *bio_src)
 	 * so we don't set nor calculate new physical/hw segment counts here
 	 */
 	bio->bi_bdev = bio_src->bi_bdev;
-	bio->bi_flags |= 1 << BIO_CLONED;
+	bio_set_flag(bio, BIO_CLONED);
 	bio->bi_rw = bio_src->bi_rw;
 	bio->bi_iter = bio_src->bi_iter;
 	bio->bi_io_vec = bio_src->bi_io_vec;
@@ -829,7 +829,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 
 	/* If we may be able to merge these biovecs, force a recount */
 	if (bio->bi_vcnt > 1 && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
-		bio->bi_flags &= ~(1 << BIO_SEG_VALID);
+		bio_clear_flag(bio, BIO_SEG_VALID);
 
  done:
 	return len;
@@ -1390,7 +1390,7 @@ struct bio *bio_map_user_iov(struct request_queue *q,
 	if (iter->type & WRITE)
 		bio->bi_rw |= REQ_WRITE;
 
-	bio->bi_flags |= (1 << BIO_USER_MAPPED);
+	bio_set_flag(bio, BIO_USER_MAPPED);
 
 	/*
 	 * subtle -- if __bio_map_user() ended up bouncing a bio,
@@ -1770,7 +1770,7 @@ static inline bool bio_remaining_done(struct bio *bio)
 	BUG_ON(atomic_read(&bio->__bi_remaining) <= 0);
 
 	if (atomic_dec_and_test(&bio->__bi_remaining)) {
-		clear_bit(BIO_CHAIN, &bio->bi_flags);
+		bio_clear_flag(bio, BIO_CHAIN);
 		return true;
 	}
 
@@ -1866,7 +1866,7 @@ void bio_trim(struct bio *bio, int offset, int size)
 	if (offset == 0 && size == bio->bi_iter.bi_size)
 		return;
 
-	clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+	bio_clear_flag(bio, BIO_SEG_VALID);
 
 	bio_advance(bio, offset << 9);
 
diff --git a/block/blk-core.c b/block/blk-core.c
index 7ef15b947b91..d1796b54e97a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -146,7 +146,7 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
 		bio->bi_error = error;
 
 	if (unlikely(rq->cmd_flags & REQ_QUIET))
-		set_bit(BIO_QUIET, &bio->bi_flags);
+		bio_set_flag(bio, BIO_QUIET);
 
 	bio_advance(bio, nbytes);
 
diff --git a/block/blk-map.c b/block/blk-map.c
index 5fe1c30bfba7..233841644c9d 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -94,7 +94,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
 		return PTR_ERR(bio);
 
 	if (map_data && map_data->null_mapped)
-		bio->bi_flags |= (1 << BIO_NULL_MAPPED);
+		bio_set_flag(bio, BIO_NULL_MAPPED);
 
 	if (bio->bi_iter.bi_size != iter->count) {
 		/*
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 30a0d9f89017..a455b9860143 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -116,7 +116,7 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio)
 		bio->bi_next = nxt;
 	}
 
-	bio->bi_flags |= (1 << BIO_SEG_VALID);
+	bio_set_flag(bio, BIO_SEG_VALID);
 }
 EXPORT_SYMBOL(blk_recount_segments);
 
diff --git a/block/bounce.c b/block/bounce.c
index f4db245b9f3a..2c310ea007ee 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -186,7 +186,7 @@ static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
 	if (!bdi_cap_stable_pages_required(&q->backing_dev_info))
 		return 0;
 
-	return test_bit(BIO_SNAP_STABLE, &bio->bi_flags);
+	return bio_flagged(bio, BIO_SNAP_STABLE);
 }
 #else
 static int must_snapshot_stable_pages(struct request_queue *q, struct bio *bio)
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 9aa7d1fb2bc1..60d0a8626e63 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1157,7 +1157,7 @@ static void make_request(struct mddev *mddev, struct bio * bio)
 	 * non-zero, then it is the number of not-completed requests.
 	 */
 	bio->bi_phys_segments = 0;
-	clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+	bio_clear_flag(bio, BIO_SEG_VALID);
 
 	if (rw == READ) {
 		/*
@@ -2711,7 +2711,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
 						/* remove last page from this bio */
 						bio->bi_vcnt--;
 						bio->bi_iter.bi_size -= len;
-						__clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+						bio_clear_flag(bio, BIO_SEG_VALID);
 					}
 					goto bio_full;
 				}
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 929e9a26d81b..316ff6f611e9 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1216,7 +1216,7 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
 	 * non-zero, then it is the number of not-completed requests.
 	 */
 	bio->bi_phys_segments = 0;
-	clear_bit(BIO_SEG_VALID, &bio->bi_flags);
+	bio_clear_flag(bio, BIO_SEG_VALID);
 
 	if (rw == READ) {
 		/*
@@ -3353,7 +3353,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr,
 				/* remove last page from this bio */
 				bio2->bi_vcnt--;
 				bio2->bi_iter.bi_size -= len;
-				__clear_bit(BIO_SEG_VALID, &bio2->bi_flags);
+				bio_clear_flag(bio2, BIO_SEG_VALID);
 			}
 			goto bio_full;
 		}
@@ -4433,7 +4433,7 @@ read_more:
 				/* Remove last page from this bio */
 				bio2->bi_vcnt--;
 				bio2->bi_iter.bi_size -= len;
-				__clear_bit(BIO_SEG_VALID, &bio2->bi_flags);
+				bio_clear_flag(bio2, BIO_SEG_VALID);
 			}
 			goto bio_full;
 		}
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 84d6eec1033e..e3d48775c9df 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4850,7 +4850,7 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
 		rcu_read_unlock();
 		raid_bio->bi_next = (void*)rdev;
 		align_bi->bi_bdev =  rdev->bdev;
-		__clear_bit(BIO_SEG_VALID, &align_bi->bi_flags);
+		bio_clear_flag(align_bi, BIO_SEG_VALID);
 
 		if (!bio_fits_rdev(align_bi) ||
 		    is_badblock(rdev, align_bi->bi_iter.bi_sector,
diff --git a/fs/buffer.c b/fs/buffer.c
index 7a49bb84ecb5..7887bb466368 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2961,7 +2961,7 @@ static void end_bio_bh_io_sync(struct bio *bio)
 {
 	struct buffer_head *bh = bio->bi_private;
 
-	if (unlikely (test_bit(BIO_QUIET,&bio->bi_flags)))
+	if (unlikely(bio_flagged(bio, BIO_QUIET)))
 		set_bit(BH_Quiet, &bh->b_state);
 
 	bh->b_end_io(bh, !bio->bi_error);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 6b918177002d..986e6e19feb5 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -304,6 +304,21 @@ static inline void bio_cnt_set(struct bio *bio, unsigned int count)
 	atomic_set(&bio->__bi_cnt, count);
 }
 
+static inline bool bio_flagged(struct bio *bio, unsigned int bit)
+{
+	return (bio->bi_flags & (1UL << bit)) != 0;
+}
+
+static inline void bio_set_flag(struct bio *bio, unsigned int bit)
+{
+	bio->bi_flags |= (1UL << bit);
+}
+
+static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
+{
+	bio->bi_flags &= ~(1UL << bit);
+}
+
 enum bip_flags {
 	BIP_BLOCK_INTEGRITY	= 1 << 0, /* block layer owns integrity data */
 	BIP_MAPPED_INTEGRITY	= 1 << 1, /* ref tag has been remapped */
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 6164fb8a817b..a765a50e780f 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -129,8 +129,6 @@ struct bio {
 #define BIO_RESET_BITS	13
 #define BIO_OWNS_VEC	13	/* bio_free() should free bvec */
 
-#define bio_flagged(bio, flag)	((bio)->bi_flags & (1 << (flag)))
-
 /*
  * top 4 bits of bio flags indicate the pool this bio came from
  */