[PATCH 3/3] block: Move discard and secure discard flags to queue limits

["Martin K. Petersen" <martin.petersen@oracle.com>]

Whether a device supports discard is currently stored two places:
max_discard_sectors in the queue limits and the discard request_queue
flag. Deprecate the queue flag and always use the topology.

Also move the secure discard flag to the queue limits so it can be
stacked as well.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
---
 block/blk-settings.c      |    3 +++
 drivers/block/brd.c       |    1 -
 drivers/md/dm-table.c     |    5 -----
 drivers/mmc/card/queue.c  |    4 +---
 drivers/mtd/mtd_blkdevs.c |    4 +---
 drivers/scsi/sd.c         |    3 +--
 include/linux/blkdev.h    |   21 +++++++++++++--------
 7 files changed, 19 insertions(+), 22 deletions(-)

diff --git a/block/blk-settings.c b/block/blk-settings.c
index f95760d..feb3e40 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -118,6 +118,7 @@ void blk_set_default_limits(struct queue_limits *lim)
 	lim->discard_alignment = 0;
 	lim->discard_misaligned = 0;
 	lim->discard_zeroes_data = 0;
+	lim->discard_secure = 0;
 	lim->logical_block_size = lim->physical_block_size = lim->io_min = 512;
 	lim->bounce_pfn = (unsigned long)(BLK_BOUNCE_ANY >> PAGE_SHIFT);
 	lim->alignment_offset = 0;
@@ -144,6 +145,7 @@ void blk_set_stacking_limits(struct queue_limits *lim)
 	lim->max_hw_sectors = INT_MAX;
 	lim->max_sectors = BLK_DEF_MAX_SECTORS;
 	lim->discard_zeroes_data = 1;
+	lim->discard_secure = 1;
 	lim->non_rotational = 1;
 }
 EXPORT_SYMBOL(blk_set_stacking_limits);
@@ -570,6 +572,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 
 	t->cluster &= b->cluster;
 	t->discard_zeroes_data &= b->discard_zeroes_data;
+	t->discard_secure &= b->discard_secure;
 	t->non_rotational &= b->non_rotational;
 
 	/* Physical block size a multiple of the logical block size? */
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index b7f51e4..3ade4e1 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -489,7 +489,6 @@ static struct brd_device *brd_alloc(int i)
 	brd->brd_queue->limits.discard_granularity = PAGE_SIZE;
 	brd->brd_queue->limits.max_discard_sectors = UINT_MAX;
 	brd->brd_queue->limits.discard_zeroes_data = 1;
-	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, brd->brd_queue);
 
 	disk = brd->brd_disk = alloc_disk(1 << part_shift);
 	if (!disk)
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 35792bf..b5c6a1b 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1185,11 +1185,6 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
 	 */
 	q->limits = *limits;
 
-	if (!dm_table_supports_discards(t))
-		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
-	else
-		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
-
 	dm_table_set_integrity(t);
 
 	/*
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 9adce86..b5c11a0 100644
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -129,7 +129,6 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 	blk_queue_prep_rq(mq->queue, mmc_prep_request);
 	blk_queue_non_rotational(mq->queue);
 	if (mmc_can_erase(card)) {
-		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, mq->queue);
 		mq->queue->limits.max_discard_sectors = UINT_MAX;
 		if (card->erased_byte == 0)
 			mq->queue->limits.discard_zeroes_data = 1;
@@ -140,8 +139,7 @@ int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock
 							card->erase_size << 9;
 		}
 		if (mmc_can_secure_erase_trim(card))
-			queue_flag_set_unlocked(QUEUE_FLAG_SECDISCARD,
-						mq->queue);
+			mq->queue->limits.discard_secure = 1;
 	}
 
 #ifdef CONFIG_MMC_BLOCK_BOUNCE
diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index a534e1f..5315163 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -408,10 +408,8 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 	new->rq->queuedata = new;
 	blk_queue_logical_block_size(new->rq, tr->blksize);
 
-	if (tr->discard) {
-		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, new->rq);
+	if (tr->discard)
 		new->rq->limits.max_discard_sectors = UINT_MAX;
-	}
 
 	gd->queue = new->rq;
 
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 7a5cf28..c958ac5 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -499,7 +499,7 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
 
 	case SD_LBP_DISABLE:
 		q->limits.max_discard_sectors = 0;
-		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
+		max_blocks = 0;
 		return;
 
 	case SD_LBP_UNMAP:
@@ -521,7 +521,6 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
 	}
 
 	q->limits.max_discard_sectors = max_blocks * (logical_block_size >> 9);
-	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
 
 	sdkp->provisioning_mode = mode;
 }
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 52a3f4c..42a374f 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -258,7 +258,7 @@ struct queue_limits {
 	unsigned char		discard_misaligned;
 	unsigned char		cluster;
 	unsigned char		discard_zeroes_data;
-
+	unsigned char		discard_secure;
 	unsigned char		non_rotational;
 };
 
@@ -399,10 +399,8 @@ struct request_queue
 #define QUEUE_FLAG_FAIL_IO     10	/* fake timeout */
 #define QUEUE_FLAG_STACKABLE   11	/* supports request stacking */
 #define QUEUE_FLAG_IO_STAT     12	/* do IO stats */
-#define QUEUE_FLAG_DISCARD     13	/* supports DISCARD */
-#define QUEUE_FLAG_NOXMERGES   14	/* No extended merges */
-#define QUEUE_FLAG_ADD_RANDOM  15	/* Contributes to random pool */
-#define QUEUE_FLAG_SECDISCARD  16	/* supports SECDISCARD */
+#define QUEUE_FLAG_NOXMERGES   13	/* No extended merges */
+#define QUEUE_FLAG_ADD_RANDOM  14	/* Contributes to random pool */
 
 #define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
 				 (1 << QUEUE_FLAG_STACKABLE)	|	\
@@ -483,9 +481,6 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
 #define blk_queue_add_random(q)	test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
 #define blk_queue_stackable(q)	\
 	test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
-#define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
-#define blk_queue_secdiscard(q)	(blk_queue_discard(q) && \
-	test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
 
 #define blk_noretry_request(rq) \
 	((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
@@ -1033,6 +1028,16 @@ static inline unsigned int blk_queue_nonrot(struct request_queue *q)
 	return q->limits.non_rotational;
 }
 
+static inline unsigned int blk_queue_discard(struct request_queue *q)
+{
+	return !!q->limits.max_discard_sectors;
+}
+
+static inline unsigned int blk_queue_secdiscard(struct request_queue *q)
+{
+	return q->limits.discard_secure;
+}
+
 static inline int queue_alignment_offset(struct request_queue *q)
 {
 	if (q->limits.misaligned)
-- 
1.7.4.4