Commit ba3f67c1 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

xen-blkfront: atomically update queue limits 



Pass the initial queue limits to blk_mq_alloc_disk and use the
blkif_set_queue_limits API to update the limits on reconnect.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarRoger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20240221125845.3610668-5-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4f81b87d

drivers/block/xen-blkfront.c

+23 −18
Original line number Diff line number Diff line
@@ -941,37 +941,35 @@ 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;

	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, UINT_MAX);

		lim->max_hw_discard_sectors = UINT_MAX;

		if (info->discard_granularity)

			rq->limits.discard_granularity = info->discard_granularity;

		rq->limits.discard_alignment = info->discard_alignment;

			lim->discard_granularity = info->discard_granularity;

		lim->discard_alignment = info->discard_alignment;

		if (info->feature_secdiscard)

			blk_queue_max_secure_erase_sectors(rq, UINT_MAX);

			lim->max_secure_erase_sectors = UINT_MAX;

	}



	/* 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)
@@ -1068,6 +1066,7 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, 
		struct blkfront_info *info, u16 sector_size,

		unsigned int physical_sector_size)

{

	struct queue_limits lim = {};

	struct gendisk *gd;

	int nr_minors = 1;

	int err;
@@ -1134,11 +1133,13 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, 
	if (err)

		goto out_release_minors;



	gd = blk_mq_alloc_disk(&info->tag_set, NULL, 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;

	}

	blk_queue_flag_set(QUEUE_FLAG_VIRT, gd->queue);



	strcpy(gd->disk_name, DEV_NAME);

	ptr = encode_disk_name(gd->disk_name + sizeof(DEV_NAME) - 1, offset);
@@ -1160,7 +1161,6 @@ static int xlvbd_alloc_gendisk(blkif_sector_t capacity, 
	info->gd = gd;

	info->sector_size = sector_size;

	info->physical_sector_size = physical_sector_size;

	blkif_set_queue_limits(info);



	xlvbd_flush(info);
@@ -2004,14 +2004,19 @@ 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;

	struct blkfront_ring_info *rinfo;



	lim = queue_limits_start_update(info->rq);

	blkfront_gather_backend_features(info);

	blkif_set_queue_limits(info);

	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);