Merge commit '5bc66170dc486556a1e36fd384463536573f4b82' into x86/urgent

From Borislav Petkov <bp@amd64.org>:

Below is a RAS fix which reverts the addition of a sysfs attribute
which we agreed is not needed, post-factum. And this should go in now
because that sysfs attribute is going to end up in 3.7 otherwise and
thus exposed to userspace; removing it then would be a lot harder.

This is done as a merge rather than a simple patch/cherry-pick since
the baseline for this patch was not in the previous x86/urgent.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 70 insertions, 12 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4a2ab7c8539..1756001210d 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -270,6 +270,7 @@ struct queue_limits {
 	unsigned int		io_min;
 	unsigned int		io_opt;
 	unsigned int		max_discard_sectors;
+	unsigned int		max_write_same_sectors;
 	unsigned int		discard_granularity;
 	unsigned int		discard_alignment;
 
@@ -540,8 +541,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 
 #define blk_account_rq(rq) \
 	(((rq)->cmd_flags & REQ_STARTED) && \
-	 ((rq)->cmd_type == REQ_TYPE_FS || \
-	  ((rq)->cmd_flags & REQ_DISCARD)))
+	 ((rq)->cmd_type == REQ_TYPE_FS))
 
 #define blk_pm_request(rq)	\
 	((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
@@ -595,17 +595,39 @@ static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
 	rl->flags &= ~flag;
 }
 
+static inline bool rq_mergeable(struct request *rq)
+{
+	if (rq->cmd_type != REQ_TYPE_FS)
+		return false;
 
-/*
- * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may
- * it already be started by driver.
- */
-#define RQ_NOMERGE_FLAGS	\
-	(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA | REQ_DISCARD)
-#define rq_mergeable(rq)	\
-	(!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
-	 (((rq)->cmd_flags & REQ_DISCARD) || \
-	  (rq)->cmd_type == REQ_TYPE_FS))
+	if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
+		return false;
+
+	return true;
+}
+
+static inline bool blk_check_merge_flags(unsigned int flags1,
+					 unsigned int flags2)
+{
+	if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
+		return false;
+
+	if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
+		return false;
+
+	if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
+		return false;
+
+	return true;
+}
+
+static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
+{
+	if (bio_data(a) == bio_data(b))
+		return true;
+
+	return false;
+}
 
 /*
  * q->prep_rq_fn return values
@@ -802,6 +824,28 @@ static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
 	return blk_rq_cur_bytes(rq) >> 9;
 }
 
+static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
+						     unsigned int cmd_flags)
+{
+	if (unlikely(cmd_flags & REQ_DISCARD))
+		return q->limits.max_discard_sectors;
+
+	if (unlikely(cmd_flags & REQ_WRITE_SAME))
+		return q->limits.max_write_same_sectors;
+
+	return q->limits.max_sectors;
+}
+
+static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
+{
+	struct request_queue *q = rq->q;
+
+	if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
+		return q->limits.max_hw_sectors;
+
+	return blk_queue_get_max_sectors(q, rq->cmd_flags);
+}
+
 /*
  * Request issue related functions.
  */
@@ -857,6 +901,8 @@ extern void blk_queue_max_segments(struct request_queue *, unsigned short);
 extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
 extern void blk_queue_max_discard_sectors(struct request_queue *q,
 		unsigned int max_discard_sectors);
+extern void blk_queue_max_write_same_sectors(struct request_queue *q,
+		unsigned int max_write_same_sectors);
 extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
 extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
 extern void blk_queue_alignment_offset(struct request_queue *q,
@@ -987,6 +1033,8 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
 extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
 extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
 		sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
+extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
+		sector_t nr_sects, gfp_t gfp_mask, struct page *page);
 extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
 			sector_t nr_sects, gfp_t gfp_mask);
 static inline int sb_issue_discard(struct super_block *sb, sector_t block,
@@ -1164,6 +1212,16 @@ static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
 	return queue_discard_zeroes_data(bdev_get_queue(bdev));
 }
 
+static inline unsigned int bdev_write_same(struct block_device *bdev)
+{
+	struct request_queue *q = bdev_get_queue(bdev);
+
+	if (q)
+		return q->limits.max_write_same_sectors;
+
+	return 0;
+}
+
 static inline int queue_dma_alignment(struct request_queue *q)
 {
 	return q ? q->dma_alignment : 511;