nvme: support ranged discard requests

NVMe supports up to 256 ranges per DSM command, so wire up support
for ranged discards up to that limit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Christoph Hellwig 2017-02-08 14:46:50 +01:00 committed by Jens Axboe
parent 1e739730c5
commit b35ba01ea6
2 changed files with 25 additions and 7 deletions

View File

@ -238,26 +238,38 @@ static inline void nvme_setup_flush(struct nvme_ns *ns,
static inline int nvme_setup_discard(struct nvme_ns *ns, struct request *req,
struct nvme_command *cmnd)
{
unsigned short segments = blk_rq_nr_discard_segments(req), n = 0;
struct nvme_dsm_range *range;
unsigned int nr_bytes = blk_rq_bytes(req);
struct bio *bio;
range = kmalloc(sizeof(*range), GFP_ATOMIC);
range = kmalloc_array(segments, sizeof(*range), GFP_ATOMIC);
if (!range)
return BLK_MQ_RQ_QUEUE_BUSY;
range->cattr = cpu_to_le32(0);
range->nlb = cpu_to_le32(nr_bytes >> ns->lba_shift);
range->slba = cpu_to_le64(nvme_block_nr(ns, blk_rq_pos(req)));
__rq_for_each_bio(bio, req) {
u64 slba = nvme_block_nr(ns, bio->bi_iter.bi_sector);
u32 nlb = bio->bi_iter.bi_size >> ns->lba_shift;
range[n].cattr = cpu_to_le32(0);
range[n].nlb = cpu_to_le32(nlb);
range[n].slba = cpu_to_le64(slba);
n++;
}
if (WARN_ON_ONCE(n != segments)) {
kfree(range);
return BLK_MQ_RQ_QUEUE_ERROR;
}
memset(cmnd, 0, sizeof(*cmnd));
cmnd->dsm.opcode = nvme_cmd_dsm;
cmnd->dsm.nsid = cpu_to_le32(ns->ns_id);
cmnd->dsm.nr = 0;
cmnd->dsm.nr = segments - 1;
cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD);
req->special_vec.bv_page = virt_to_page(range);
req->special_vec.bv_offset = offset_in_page(range);
req->special_vec.bv_len = sizeof(*range);
req->special_vec.bv_len = sizeof(*range) * segments;
req->rq_flags |= RQF_SPECIAL_PAYLOAD;
return BLK_MQ_RQ_QUEUE_OK;
@ -871,6 +883,9 @@ static void nvme_config_discard(struct nvme_ns *ns)
struct nvme_ctrl *ctrl = ns->ctrl;
u32 logical_block_size = queue_logical_block_size(ns->queue);
BUILD_BUG_ON(PAGE_SIZE / sizeof(struct nvme_dsm_range) <
NVME_DSM_MAX_RANGES);
if (ctrl->quirks & NVME_QUIRK_DISCARD_ZEROES)
ns->queue->limits.discard_zeroes_data = 1;
else
@ -879,6 +894,7 @@ static void nvme_config_discard(struct nvme_ns *ns)
ns->queue->limits.discard_alignment = logical_block_size;
ns->queue->limits.discard_granularity = logical_block_size;
blk_queue_max_discard_sectors(ns->queue, UINT_MAX);
blk_queue_max_discard_segments(ns->queue, NVME_DSM_MAX_RANGES);
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue);
}

View File

@ -553,6 +553,8 @@ enum {
NVME_DSMGMT_AD = 1 << 2,
};
#define NVME_DSM_MAX_RANGES 256
struct nvme_dsm_range {
__le32 cattr;
__le32 nlb;