From 0e5e4f0e56aca0df1d5648db0be9028bd573b25c Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Fri, 9 Nov 2012 16:33:05 -0700 Subject: [PATCH 1/1] NVMe: Add discard support for capable devices This adds discard support to block queues if the nvme device is capable of deallocating blocks as indicated by the controller's optional command support. A discard flagged bio request will submit an NVMe deallocate Data Set Management command for the requested blocks. Signed-off-by: Keith Busch Signed-off-by: Matthew Wilcox --- drivers/block/nvme.c | 60 +++++++++++++++++++++++++++++++++++++++++++- include/linux/nvme.h | 32 +++++++++++++++++++++++ 2 files changed, 91 insertions(+), 1 deletion(-) diff --git a/drivers/block/nvme.c b/drivers/block/nvme.c index 9dcefe40380b..26e266072079 100644 --- a/drivers/block/nvme.c +++ b/drivers/block/nvme.c @@ -80,6 +80,7 @@ struct nvme_dev { char model[40]; char firmware_rev[8]; u32 max_hw_sectors; + u16 oncs; }; /* @@ -510,6 +511,44 @@ static int nvme_map_bio(struct device *dev, struct nvme_iod *iod, return length; } +/* + * We reuse the small pool to allocate the 16-byte range here as it is not + * worth having a special pool for these or additional cases to handle freeing + * the iod. + */ +static int nvme_submit_discard(struct nvme_queue *nvmeq, struct nvme_ns *ns, + struct bio *bio, struct nvme_iod *iod, int cmdid) +{ + struct nvme_dsm_range *range; + struct nvme_command *cmnd = &nvmeq->sq_cmds[nvmeq->sq_tail]; + + range = dma_pool_alloc(nvmeq->dev->prp_small_pool, GFP_ATOMIC, + &iod->first_dma); + if (!range) + return -ENOMEM; + + iod_list(iod)[0] = (__le64 *)range; + iod->npages = 0; + + range->cattr = cpu_to_le32(0); + range->nlb = cpu_to_le32(bio->bi_size >> ns->lba_shift); + range->slba = cpu_to_le64(bio->bi_sector >> (ns->lba_shift - 9)); + + memset(cmnd, 0, sizeof(*cmnd)); + cmnd->dsm.opcode = nvme_cmd_dsm; + cmnd->dsm.command_id = cmdid; + cmnd->dsm.nsid = cpu_to_le32(ns->ns_id); + cmnd->dsm.prp1 = cpu_to_le64(iod->first_dma); + cmnd->dsm.nr = 0; + cmnd->dsm.attributes = cpu_to_le32(NVME_DSMGMT_AD); + + if (++nvmeq->sq_tail == nvmeq->q_depth) + nvmeq->sq_tail = 0; + writel(nvmeq->sq_tail, nvmeq->q_db); + + return 0; +} + static int nvme_submit_flush(struct nvme_queue *nvmeq, struct nvme_ns *ns, int cmdid) { @@ -567,6 +606,12 @@ static int nvme_submit_bio_queue(struct nvme_queue *nvmeq, struct nvme_ns *ns, if (unlikely(cmdid < 0)) goto free_iod; + if (bio->bi_rw & REQ_DISCARD) { + result = nvme_submit_discard(nvmeq, ns, bio, iod, cmdid); + if (result) + goto free_cmdid; + return result; + } if ((bio->bi_rw & REQ_FLUSH) && !psegs) return nvme_submit_flush(nvmeq, ns, cmdid); @@ -1347,6 +1392,16 @@ static void nvme_put_ns_idx(int index) spin_unlock(&dev_list_lock); } +static void nvme_config_discard(struct nvme_ns *ns) +{ + u32 logical_block_size = queue_logical_block_size(ns->queue); + ns->queue->limits.discard_zeroes_data = 0; + ns->queue->limits.discard_alignment = logical_block_size; + ns->queue->limits.discard_granularity = logical_block_size; + ns->queue->limits.max_discard_sectors = 0xffffffff; + queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue); +} + static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int nsid, struct nvme_id_ns *id, struct nvme_lba_range_type *rt) { @@ -1366,7 +1421,6 @@ static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int nsid, ns->queue->queue_flags = QUEUE_FLAG_DEFAULT; queue_flag_set_unlocked(QUEUE_FLAG_NOMERGES, ns->queue); queue_flag_set_unlocked(QUEUE_FLAG_NONROT, ns->queue); -/* queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, ns->queue); */ blk_queue_make_request(ns->queue, nvme_make_request); ns->dev = dev; ns->queue->queuedata = ns; @@ -1392,6 +1446,9 @@ static struct nvme_ns *nvme_alloc_ns(struct nvme_dev *dev, int nsid, sprintf(disk->disk_name, "nvme%dn%d", dev->instance, nsid); set_capacity(disk, le64_to_cpup(&id->nsze) << (ns->lba_shift - 9)); + if (dev->oncs & NVME_CTRL_ONCS_DSM) + nvme_config_discard(ns); + return ns; out_free_queue: @@ -1520,6 +1577,7 @@ static int nvme_dev_add(struct nvme_dev *dev) ctrl = mem; nn = le32_to_cpup(&ctrl->nn); + dev->oncs = le16_to_cpup(&ctrl->oncs); memcpy(dev->serial, ctrl->sn, sizeof(ctrl->sn)); memcpy(dev->model, ctrl->mn, sizeof(ctrl->mn)); memcpy(dev->firmware_rev, ctrl->fr, sizeof(ctrl->fr)); diff --git a/include/linux/nvme.h b/include/linux/nvme.h index 4fa3b0b9b071..bde44c1fd213 100644 --- a/include/linux/nvme.h +++ b/include/linux/nvme.h @@ -107,6 +107,12 @@ struct nvme_id_ctrl { __u8 vs[1024]; }; +enum { + NVME_CTRL_ONCS_COMPARE = 1 << 0, + NVME_CTRL_ONCS_WRITE_UNCORRECTABLE = 1 << 1, + NVME_CTRL_ONCS_DSM = 1 << 2, +}; + struct nvme_lbaf { __le16 ms; __u8 ds; @@ -246,6 +252,31 @@ enum { NVME_RW_DSM_COMPRESSED = 1 << 7, }; +struct nvme_dsm_cmd { + __u8 opcode; + __u8 flags; + __u16 command_id; + __le32 nsid; + __u64 rsvd2[2]; + __le64 prp1; + __le64 prp2; + __le32 nr; + __le32 attributes; + __u32 rsvd12[4]; +}; + +enum { + NVME_DSMGMT_IDR = 1 << 0, + NVME_DSMGMT_IDW = 1 << 1, + NVME_DSMGMT_AD = 1 << 2, +}; + +struct nvme_dsm_range { + __le32 cattr; + __le32 nlb; + __le64 slba; +}; + /* Admin commands */ enum nvme_admin_opcode { @@ -372,6 +403,7 @@ struct nvme_command { struct nvme_create_sq create_sq; struct nvme_delete_queue delete_queue; struct nvme_download_firmware dlfw; + struct nvme_dsm_cmd dsm; }; }; -- 2.20.1