[PATCHv13 10/11] nvme: register fdp parameters with the block layer

[Keith Busch <kbusch@meta.com>]

From: Keith Busch <kbusch@kernel.org>

Register the device data placement limits if supported. This is just
registering the limits with the block layer. Nothing beyond reporting
these attributes is happening in this patch.

Merges parts from a patch by Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-nvme/20241119121632.1225556-15-hch@lst.de/ 

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
 drivers/nvme/host/core.c | 139 +++++++++++++++++++++++++++++++++++++++
 drivers/nvme/host/nvme.h |   2 +
 2 files changed, 141 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index c2a3585a3fa59..f7aeda601fcd6 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -38,6 +38,8 @@ struct nvme_ns_info {
 	u32 nsid;
 	__le32 anagrpid;
 	u8 pi_offset;
+	u16 endgid;
+	u64 runs;
 	bool is_shared;
 	bool is_readonly;
 	bool is_ready;
@@ -1613,6 +1615,7 @@ static int nvme_ns_info_from_identify(struct nvme_ctrl *ctrl,
 	info->is_shared = id->nmic & NVME_NS_NMIC_SHARED;
 	info->is_readonly = id->nsattr & NVME_NS_ATTR_RO;
 	info->is_ready = true;
+	info->endgid = le16_to_cpu(id->endgid);
 	if (ctrl->quirks & NVME_QUIRK_BOGUS_NID) {
 		dev_info(ctrl->device,
 			 "Ignoring bogus Namespace Identifiers\n");
@@ -1653,6 +1656,7 @@ static int nvme_ns_info_from_id_cs_indep(struct nvme_ctrl *ctrl,
 		info->is_ready = id->nstat & NVME_NSTAT_NRDY;
 		info->is_rotational = id->nsfeat & NVME_NS_ROTATIONAL;
 		info->no_vwc = id->nsfeat & NVME_NS_VWC_NOT_PRESENT;
+		info->endgid = le16_to_cpu(id->endgid);
 	}
 	kfree(id);
 	return ret;
@@ -2147,6 +2151,127 @@ static int nvme_update_ns_info_generic(struct nvme_ns *ns,
 	return ret;
 }
 
+static int nvme_query_fdp_granularity(struct nvme_ctrl *ctrl,
+				      struct nvme_ns_info *info, u8 fdp_idx)
+{
+	struct nvme_fdp_config_log hdr, *h;
+	struct nvme_fdp_config_desc *desc;
+	size_t size = sizeof(hdr);
+	int i, n, ret;
+	void *log;
+
+	ret = nvme_get_log_lsi(ctrl, 0, NVME_LOG_FDP_CONFIGS, 0,
+			       NVME_CSI_NVM, &hdr, size, 0, info->endgid);
+	if (ret) {
+		dev_warn(ctrl->device,
+			 "FDP configs log header status:0x%x endgid:%x\n", ret,
+			 info->endgid);
+		return ret;
+	}
+
+	size = le32_to_cpu(hdr.sze);
+	h = kzalloc(size, GFP_KERNEL);
+	if (!h) {
+		dev_warn(ctrl->device,
+			 "failed to allocate %lu bytes for FDP config log\n",
+			 size);
+		return -ENOMEM;
+	}
+
+	ret = nvme_get_log_lsi(ctrl, 0, NVME_LOG_FDP_CONFIGS, 0,
+			       NVME_CSI_NVM, h, size, 0, info->endgid);
+	if (ret) {
+		dev_warn(ctrl->device,
+			 "FDP configs log status:0x%x endgid:%x\n", ret,
+			 info->endgid);
+		goto out;
+	}
+
+	n = le16_to_cpu(h->numfdpc) + 1;
+	if (fdp_idx > n) {
+		dev_warn(ctrl->device, "FDP index:%d out of range:%d\n",
+			 fdp_idx, n);
+		/* Proceed without registering FDP streams */
+		ret = 0;
+		goto out;
+	}
+
+	log = h + 1;
+	desc = log;
+	for (i = 0; i < fdp_idx; i++) {
+		log += le16_to_cpu(desc->dsze);
+		desc = log;
+	}
+
+	if (le32_to_cpu(desc->nrg) > 1) {
+		dev_warn(ctrl->device, "FDP NRG > 1 not supported\n");
+		ret = 0;
+		goto out;
+	}
+
+	info->runs = le64_to_cpu(desc->runs);
+out:
+	kfree(h);
+	return ret;
+}
+
+static int nvme_query_fdp_info(struct nvme_ns *ns, struct nvme_ns_info *info)
+{
+	struct nvme_ns_head *head = ns->head;
+	struct nvme_ctrl *ctrl = ns->ctrl;
+	struct nvme_fdp_ruh_status *ruhs;
+	struct nvme_fdp_config fdp;
+	struct nvme_command c = {};
+	size_t size;
+	int ret;
+
+	/*
+	 * The FDP configuration is static for the lifetime of the namespace,
+	 * so return immediately if we've already registered this namespaces's
+	 * streams.
+	 */
+	if (head->nr_plids)
+		return 0;
+
+	ret = nvme_get_features(ctrl, NVME_FEAT_FDP, info->endgid, NULL, 0,
+				&fdp);
+	if (ret) {
+		dev_warn(ctrl->device, "FDP get feature status:0x%x\n", ret);
+		return ret;
+	}
+
+	if (!(fdp.flags & FDPCFG_FDPE))
+		return 0;
+
+	ret = nvme_query_fdp_granularity(ctrl, info, fdp.fdpcidx);
+	if (!info->runs)
+		return ret;
+
+	size = struct_size(ruhs, ruhsd, S8_MAX - 1);
+	ruhs = kzalloc(size, GFP_KERNEL);
+	if (!ruhs) {
+		dev_warn(ctrl->device,
+			 "failed to allocate %lu bytes for FDP io-mgmt\n",
+			 size);
+		return -ENOMEM;
+	}
+
+	c.imr.opcode = nvme_cmd_io_mgmt_recv;
+	c.imr.nsid = cpu_to_le32(head->ns_id);
+	c.imr.mo = NVME_IO_MGMT_RECV_MO_RUHS;
+	c.imr.numd = cpu_to_le32(nvme_bytes_to_numd(size));
+	ret = nvme_submit_sync_cmd(ns->queue, &c, ruhs, size);
+	if (ret) {
+		dev_warn(ctrl->device, "FDP io-mgmt status:0x%x\n", ret);
+		goto free;
+	}
+
+	head->nr_plids = le16_to_cpu(ruhs->nruhsd);
+free:
+	kfree(ruhs);
+	return ret;
+}
+
 static int nvme_update_ns_info_block(struct nvme_ns *ns,
 		struct nvme_ns_info *info)
 {
@@ -2183,6 +2308,12 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns,
 			goto out;
 	}
 
+	if (ns->ctrl->ctratt & NVME_CTRL_ATTR_FDPS) {
+		ret = nvme_query_fdp_info(ns, info);
+		if (ret < 0)
+			goto out;
+	}
+
 	blk_mq_freeze_queue(ns->disk->queue);
 	ns->head->lba_shift = id->lbaf[lbaf].ds;
 	ns->head->nuse = le64_to_cpu(id->nuse);
@@ -2216,6 +2347,12 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns,
 	if (!nvme_init_integrity(ns->head, &lim, info))
 		capacity = 0;
 
+	lim.max_write_streams = ns->head->nr_plids;
+	if (lim.max_write_streams)
+		lim.write_stream_granularity = max(info->runs, U32_MAX);
+	else
+		lim.write_stream_granularity = 0;
+
 	ret = queue_limits_commit_update(ns->disk->queue, &lim);
 	if (ret) {
 		blk_mq_unfreeze_queue(ns->disk->queue);
@@ -2318,6 +2455,8 @@ static int nvme_update_ns_info(struct nvme_ns *ns, struct nvme_ns_info *info)
 			ns->head->disk->flags |= GENHD_FL_HIDDEN;
 		else
 			nvme_init_integrity(ns->head, &lim, info);
+		lim.max_write_streams = ns_lim->max_write_streams;
+		lim.write_stream_granularity = ns_lim->write_stream_granularity;
 		ret = queue_limits_commit_update(ns->head->disk->queue, &lim);
 
 		set_capacity_and_notify(ns->head->disk, get_capacity(ns->disk));
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index c1995d89ffdb8..4b412cd8001f1 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -491,6 +491,8 @@ struct nvme_ns_head {
 	struct device		cdev_device;
 
 	struct gendisk		*disk;
+
+	u16			nr_plids;
 #ifdef CONFIG_NVME_MULTIPATH
 	struct bio_list		requeue_list;
 	spinlock_t		requeue_lock;
-- 
2.43.5