1 files changed, 65 insertions, 66 deletions

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 434fab306777..04fc6b552c04 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -493,11 +493,11 @@ static void blkif_restart_queue_callback(void *arg)
 	schedule_work(&rinfo->work);
 }
 
-static int blkif_getgeo(struct block_device *bd, struct hd_geometry *hg)
+static int blkif_getgeo(struct gendisk *disk, struct hd_geometry *hg)
 {
 	/* We don't have real geometry info, but let's at least return
 	   values consistent with the size of the device */
-	sector_t nsect = get_capacity(bd->bd_disk);
+	sector_t nsect = get_capacity(disk);
 	sector_t cylinders = nsect;
 
 	hg->heads = 0xff;
@@ -751,7 +751,7 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
 	id = blkif_ring_get_request(rinfo, req, &final_ring_req);
 	ring_req = &rinfo->shadow[id].req;
 
-	num_sg = blk_rq_map_sg(req->q, req, rinfo->shadow[id].sg);
+	num_sg = blk_rq_map_sg(req, rinfo->shadow[id].sg);
 	num_grant = 0;
 	/* Calculate the number of grant used */
 	for_each_sg(rinfo->shadow[id].sg, sg, num_sg, i)
@@ -788,6 +788,11 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
 			 * A barrier request a superset of FUA, so we can
 			 * implement it the same way.  (It's also a FLUSH+FUA,
 			 * since it is guaranteed ordered WRT previous writes.)
+			 *
+			 * Note that can end up here with a FUA write and the
+			 * flags cleared.  This happens when the flag was
+			 * run-time disabled after a failing I/O, and we'll
+			 * simplify submit it as a normal write.
 			 */
 			if (info->feature_flush && info->feature_fua)
 				ring_req->operation =
@@ -795,8 +800,6 @@ static int blkif_queue_rw_req(struct request *req, struct blkfront_ring_info *ri
 			else if (info->feature_flush)
 				ring_req->operation =
 					BLKIF_OP_FLUSH_DISKCACHE;
-			else
-				ring_req->operation = 0;
 		}
 		ring_req->u.rw.nr_segments = num_grant;
 		if (unlikely(require_extra_req)) {
@@ -887,16 +890,6 @@ static inline void flush_requests(struct blkfront_ring_info *rinfo)
 		notify_remote_via_irq(rinfo->irq);
 }
 
-static inline bool blkif_request_flush_invalid(struct request *req,
-					       struct blkfront_info *info)
-{
-	return (blk_rq_is_passthrough(req) ||
-		((req_op(req) == REQ_OP_FLUSH) &&
-		 !info->feature_flush) ||
-		((req->cmd_flags & REQ_FUA) &&
-		 !info->feature_fua));
-}
-
 static blk_status_t blkif_queue_rq(struct blk_mq_hw_ctx *hctx,
 			  const struct blk_mq_queue_data *qd)
 {
@@ -908,12 +901,22 @@ static blk_status_t blkif_queue_rq(struct blk_mq_hw_ctx *hctx,
 	rinfo = get_rinfo(info, qid);
 	blk_mq_start_request(qd->rq);
 	spin_lock_irqsave(&rinfo->ring_lock, flags);
-	if (RING_FULL(&rinfo->ring))
-		goto out_busy;
 
-	if (blkif_request_flush_invalid(qd->rq, rinfo->dev_info))
-		goto out_err;
+	/*
+	 * Check if the backend actually supports flushes.
+	 *
+	 * While the block layer won't send us flushes if we don't claim to
+	 * support them, the Xen protocol allows the backend to revoke support
+	 * at any time.  That is of course a really bad idea and dangerous, but
+	 * has been allowed for 10+ years.  In that case we simply clear the
+	 * flags, and directly return here for an empty flush and ignore the
+	 * FUA flag later on.
+	 */
+	if (unlikely(req_op(qd->rq) == REQ_OP_FLUSH && !info->feature_flush))
+		goto complete;
 
+	if (RING_FULL(&rinfo->ring))
+		goto out_busy;
 	if (blkif_queue_request(qd->rq, rinfo))
 		goto out_busy;
 
@@ -921,14 +924,14 @@ static blk_status_t blkif_queue_rq(struct blk_mq_hw_ctx *hctx,
 	spin_unlock_irqrestore(&rinfo->ring_lock, flags);
 	return BLK_STS_OK;
 
-out_err:
-	spin_unlock_irqrestore(&rinfo->ring_lock, flags);
-	return BLK_STS_IOERR;
-
 out_busy:
 	blk_mq_stop_hw_queue(hctx);
 	spin_unlock_irqrestore(&rinfo->ring_lock, flags);
 	return BLK_STS_DEV_RESOURCE;
+complete:
+	spin_unlock_irqrestore(&rinfo->ring_lock, flags);
+	blk_mq_end_request(qd->rq, BLK_STS_OK);
+	return BLK_STS_OK;
 }
 
 static void blkif_complete_rq(struct request *rq)
@@ -941,39 +944,41 @@ static const struct blk_mq_ops blkfront_mq_ops = {
 	.complete = blkif_complete_rq,
 };
 
-static void blkif_set_queue_limits(struct blkfront_info *info)
+static void blkif_set_queue_limits(const struct blkfront_info *info,
+		struct queue_limits *lim)
 {
-	struct request_queue *rq = info->rq;
-	struct gendisk *gd = info->gd;
 	unsigned int segments = info->max_indirect_segments ? :
 				BLKIF_MAX_SEGMENTS_PER_REQUEST;
 
-	blk_queue_flag_set(QUEUE_FLAG_VIRT, rq);
-
 	if (info->feature_discard) {
-		blk_queue_max_discard_sectors(rq, get_capacity(gd));
-		rq->limits.discard_granularity = info->discard_granularity ?:
-						 info->physical_sector_size;
-		rq->limits.discard_alignment = info->discard_alignment;
+		lim->max_hw_discard_sectors = UINT_MAX;
+		if (info->discard_granularity)
+			lim->discard_granularity = info->discard_granularity;
+		lim->discard_alignment = info->discard_alignment;
 		if (info->feature_secdiscard)
-			blk_queue_max_secure_erase_sectors(rq,
-							   get_capacity(gd));
+			lim->max_secure_erase_sectors = UINT_MAX;
+	}
+
+	if (info->feature_flush) {
+		lim->features |= BLK_FEAT_WRITE_CACHE;
+		if (info->feature_fua)
+			lim->features |= BLK_FEAT_FUA;
 	}
 
 	/* Hard sector size and max sectors impersonate the equiv. hardware. */
-	blk_queue_logical_block_size(rq, info->sector_size);
-	blk_queue_physical_block_size(rq, info->physical_sector_size);
-	blk_queue_max_hw_sectors(rq, (segments * XEN_PAGE_SIZE) / 512);
+	lim->logical_block_size = info->sector_size;
+	lim->physical_block_size = info->physical_sector_size;
+	lim->max_hw_sectors = (segments * XEN_PAGE_SIZE) / 512;
 
 	/* Each segment in a request is up to an aligned page in size. */
-	blk_queue_segment_boundary(rq, PAGE_SIZE - 1);
-	blk_queue_max_segment_size(rq, PAGE_SIZE);
+	lim->seg_boundary_mask = PAGE_SIZE - 1;
+	lim->max_segment_size = PAGE_SIZE;
 
 	/* Ensure a merged request will fit in a single I/O ring slot. */
-	blk_queue_max_segments(rq, segments / GRANTS_PER_PSEG);
+	lim->max_segments = segments / GRANTS_PER_PSEG;
 
 	/* Make sure buffer addresses are sector-aligned. */
-	blk_queue_dma_alignment(rq, 511);
+	lim->dma_alignment = 511;
 }
 
 static const char *flush_info(struct blkfront_info *info)
@@ -988,8 +993,6 @@ static const char *flush_info(struct blkfront_info *info)
 
 static void xlvbd_flush(struct blkfront_info *info)
 {
-	blk_queue_write_cache(info->rq, info->feature_flush ? true : false,
-			      info->feature_fua ? true : false);
 	pr_info("blkfront: %s: %s %s %s %s %s %s %s\n",
 		info->gd->disk_name, flush_info(info),
 		"persistent grants:", info->feature_persistent ?
@@ -1067,9 +1070,9 @@ static char *encode_disk_name(char *ptr, unsigned int n)
 }
 
 static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
-		struct blkfront_info *info, u16 sector_size,
-		unsigned int physical_sector_size)
+		struct blkfront_info *info)
 {
+	struct queue_limits lim = {};
 	struct gendisk *gd;
 	int nr_minors = 1;
 	int err;
@@ -1128,7 +1131,6 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 	} else
 		info->tag_set.queue_depth = BLK_RING_SIZE(info);
 	info->tag_set.numa_node = NUMA_NO_NODE;
-	info->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
 	info->tag_set.cmd_size = sizeof(struct blkif_req);
 	info->tag_set.driver_data = info;
 
@@ -1136,7 +1138,8 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 	if (err)
 		goto out_release_minors;
 
-	gd = blk_mq_alloc_disk(&info->tag_set, info);
+	blkif_set_queue_limits(info, &lim);
+	gd = blk_mq_alloc_disk(&info->tag_set, &lim, info);
 	if (IS_ERR(gd)) {
 		err = PTR_ERR(gd);
 		goto out_free_tag_set;
@@ -1160,9 +1163,6 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity,
 
 	info->rq = gd->queue;
 	info->gd = gd;
-	info->sector_size = sector_size;
-	info->physical_sector_size = physical_sector_size;
-	blkif_set_queue_limits(info);
 
 	xlvbd_flush(info);
 
@@ -1607,8 +1607,8 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
 				blkif_req(req)->error = BLK_STS_NOTSUPP;
 				info->feature_discard = 0;
 				info->feature_secdiscard = 0;
-				blk_queue_max_discard_sectors(rq, 0);
-				blk_queue_max_secure_erase_sectors(rq, 0);
+				blk_queue_disable_discard(rq);
+				blk_queue_disable_secure_erase(rq);
 			}
 			break;
 		case BLKIF_OP_FLUSH_DISKCACHE:
@@ -1629,7 +1629,6 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
 					blkif_req(req)->error = BLK_STS_OK;
 				info->feature_fua = 0;
 				info->feature_flush = 0;
-				xlvbd_flush(info);
 			}
 			fallthrough;
 		case BLKIF_OP_READ:
@@ -2006,18 +2005,19 @@ static int blkfront_probe(struct xenbus_device *dev,
 
 static int blkif_recover(struct blkfront_info *info)
 {
+	struct queue_limits lim;
 	unsigned int r_index;
 	struct request *req, *n;
 	int rc;
 	struct bio *bio;
-	unsigned int segs;
 	struct blkfront_ring_info *rinfo;
 
+	lim = queue_limits_start_update(info->rq);
 	blkfront_gather_backend_features(info);
-	/* Reset limits changed by blk_mq_update_nr_hw_queues(). */
-	blkif_set_queue_limits(info);
-	segs = info->max_indirect_segments ? : BLKIF_MAX_SEGMENTS_PER_REQUEST;
-	blk_queue_max_segments(info->rq, segs / GRANTS_PER_PSEG);
+	blkif_set_queue_limits(info, &lim);
+	rc = queue_limits_commit_update(info->rq, &lim);
+	if (rc)
+		return rc;
 
 	for_each_rinfo(info, rinfo, r_index) {
 		rc = blkfront_setup_indirect(rinfo);
@@ -2037,7 +2037,9 @@ static int blkif_recover(struct blkfront_info *info)
 	list_for_each_entry_safe(req, n, &info->requests, queuelist) {
 		/* Requeue pending requests (flush or discard) */
 		list_del_init(&req->queuelist);
-		BUG_ON(req->nr_phys_segments > segs);
+		BUG_ON(req->nr_phys_segments >
+		       (info->max_indirect_segments ? :
+			BLKIF_MAX_SEGMENTS_PER_REQUEST));
 		blk_mq_requeue_request(req, false);
 	}
 	blk_mq_start_stopped_hw_queues(info->rq, true);
@@ -2314,8 +2316,6 @@ static void blkfront_gather_backend_features(struct blkfront_info *info)
 static void blkfront_connect(struct blkfront_info *info)
 {
 	unsigned long long sectors;
-	unsigned long sector_size;
-	unsigned int physical_sector_size;
 	int err, i;
 	struct blkfront_ring_info *rinfo;
 
@@ -2354,7 +2354,7 @@ static void blkfront_connect(struct blkfront_info *info)
 	err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
 			    "sectors", "%llu", &sectors,
 			    "info", "%u", &info->vdisk_info,
-			    "sector-size", "%lu", &sector_size,
+			    "sector-size", "%lu", &info->sector_size,
 			    NULL);
 	if (err) {
 		xenbus_dev_fatal(info->xbdev, err,
@@ -2368,9 +2368,9 @@ static void blkfront_connect(struct blkfront_info *info)
 	 * provide this. Assume physical sector size to be the same as
 	 * sector_size in that case.
 	 */
-	physical_sector_size = xenbus_read_unsigned(info->xbdev->otherend,
+	info->physical_sector_size = xenbus_read_unsigned(info->xbdev->otherend,
 						    "physical-sector-size",
-						    sector_size);
+						    info->sector_size);
 	blkfront_gather_backend_features(info);
 	for_each_rinfo(info, rinfo, i) {
 		err = blkfront_setup_indirect(rinfo);
@@ -2382,8 +2382,7 @@ static void blkfront_connect(struct blkfront_info *info)
 		}
 	}
 
-	err = xlvbd_alloc_gendisk(sectors, info, sector_size,
-				  physical_sector_size);
+	err = xlvbd_alloc_gendisk(sectors, info);
 	if (err) {
 		xenbus_dev_fatal(info->xbdev, err, "xlvbd_add at %s",
 				 info->xbdev->otherend);