[RFC-v2 07/11] nvmet/io-cmd: Hookup sbc_ops->execute_rw backend ops
Nicholas A. Bellinger
nab at linux-iscsi.org
Mon Jun 13 21:35:42 PDT 2016
From: Nicholas Bellinger <nab at linux-iscsi.org>
This patch converts nvmet_execute_rw() to utilize sbc_ops->execute_rw()
for target_iostate + target_iomem based I/O submission into existing
backends drivers via configfs in /sys/kernel/config/target/core/.
This includes support for passing T10-PI scatterlists via target_iomem
into existing sbc_ops->execute_rw() logic, and is functioning with
IBLOCK, FILEIO, and RAMDISK.
Note the preceeding target/iblock patch absorbs inline bio + bvecs
and blk_poll() optimizations from Ming + Sagi in nvmet/io-cmd into
target_core_iblock.c code.
Cc: Jens Axboe <axboe at fb.com>
Cc: Christoph Hellwig <hch at lst.de>
Cc: Martin Petersen <martin.petersen at oracle.com>
Cc: Sagi Grimberg <sagi at grimberg.me>
Cc: Hannes Reinecke <hare at suse.de>
Cc: Mike Christie <michaelc at cs.wisc.edu>
Signed-off-by: Nicholas Bellinger <nab at linux-iscsi.org>
---
drivers/nvme/target/io-cmd.c | 116 ++++++++++++++++++++++---------------------
drivers/nvme/target/nvmet.h | 7 +++
2 files changed, 67 insertions(+), 56 deletions(-)
diff --git a/drivers/nvme/target/io-cmd.c b/drivers/nvme/target/io-cmd.c
index 38c2e97..133a14a 100644
--- a/drivers/nvme/target/io-cmd.c
+++ b/drivers/nvme/target/io-cmd.c
@@ -14,20 +14,16 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/blkdev.h>
#include <linux/module.h>
+#include <target/target_core_base.h>
+#include <target/target_core_backend.h>
#include "nvmet.h"
-#if 0
-static void nvmet_bio_done(struct bio *bio)
+static void nvmet_complete_ios(struct target_iostate *ios, u16 status)
{
- struct nvmet_req *req = bio->bi_private;
-
- nvmet_req_complete(req,
- bio->bi_error ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
+ struct nvmet_req *req = container_of(ios, struct nvmet_req, t_iostate);
- if (bio != &req->inline_bio)
- bio_put(bio);
+ nvmet_req_complete(req, status ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
}
-#endif
static inline u32 nvmet_rw_len(struct nvmet_req *req)
{
@@ -35,72 +31,80 @@ static inline u32 nvmet_rw_len(struct nvmet_req *req)
req->ns->blksize_shift;
}
-#if 0
-static void nvmet_inline_bio_init(struct nvmet_req *req)
-{
- struct bio *bio = &req->inline_bio;
-
- bio_init(bio);
- bio->bi_max_vecs = NVMET_MAX_INLINE_BIOVEC;
- bio->bi_io_vec = req->inline_bvec;
-}
-#endif
-
static void nvmet_execute_rw(struct nvmet_req *req)
{
-#if 0
- int sg_cnt = req->sg_cnt;
- struct scatterlist *sg;
- struct bio *bio;
+ struct target_iostate *ios = &req->t_iostate;
+ struct target_iomem *iomem = &req->t_iomem;
+ struct se_device *dev = rcu_dereference_raw(req->ns->dev);
+ struct sbc_ops *sbc_ops = dev->transport->sbc_ops;
sector_t sector;
- blk_qc_t cookie;
- int rw, i;
-#endif
+ enum dma_data_direction data_direction;
+ sense_reason_t rc;
+ bool fua_write = false, prot_enabled = false;
+
+ if (!sbc_ops || !sbc_ops->execute_rw) {
+ nvmet_req_complete(req, NVME_SC_INTERNAL | NVME_SC_DNR);
+ return;
+ }
+
if (!req->sg_cnt) {
nvmet_req_complete(req, 0);
return;
}
-#if 0
+
if (req->cmd->rw.opcode == nvme_cmd_write) {
if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
- rw = WRITE_FUA;
- else
- rw = WRITE;
+ fua_write = true;
+
+ data_direction = DMA_TO_DEVICE;
} else {
- rw = READ;
+ data_direction = DMA_FROM_DEVICE;
}
sector = le64_to_cpu(req->cmd->rw.slba);
sector <<= (req->ns->blksize_shift - 9);
- nvmet_inline_bio_init(req);
- bio = &req->inline_bio;
- bio->bi_bdev = req->ns->bdev;
- bio->bi_iter.bi_sector = sector;
- bio->bi_private = req;
- bio->bi_end_io = nvmet_bio_done;
-
- for_each_sg(req->sg, sg, req->sg_cnt, i) {
- while (bio_add_page(bio, sg_page(sg), sg->length, sg->offset)
- != sg->length) {
- struct bio *prev = bio;
-
- bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
- bio->bi_bdev = req->ns->bdev;
- bio->bi_iter.bi_sector = sector;
-
- bio_chain(bio, prev);
- cookie = submit_bio(rw, prev);
- }
+ ios->t_task_lba = sector;
+ ios->data_length = nvmet_rw_len(req);
+ ios->data_direction = data_direction;
+ iomem->t_data_sg = req->sg;
+ iomem->t_data_nents = req->sg_cnt;
+ iomem->t_prot_sg = req->prot_sg;
+ iomem->t_prot_nents = req->prot_sg_cnt;
+
+ // XXX: Make common between sbc_check_prot and nvme-target
+ switch (dev->dev_attrib.pi_prot_type) {
+ case TARGET_DIF_TYPE3_PROT:
+ ios->reftag_seed = 0xffffffff;
+ prot_enabled = true;
+ break;
+ case TARGET_DIF_TYPE1_PROT:
+ ios->reftag_seed = ios->t_task_lba;
+ prot_enabled = true;
+ break;
+ default:
+ break;
+ }
- sector += sg->length >> 9;
- sg_cnt--;
+ if (prot_enabled) {
+ ios->prot_type = dev->dev_attrib.pi_prot_type;
+ ios->prot_length = dev->prot_length *
+ (le16_to_cpu(req->cmd->rw.length) + 1);
+#if 0
+ printk("req->cmd->rw.length: %u\n", le16_to_cpu(req->cmd->rw.length));
+ printk("nvmet_rw_len: %u\n", nvmet_rw_len(req));
+ printk("req->se_cmd.prot_type: %d\n", req->se_cmd.prot_type);
+ printk("req->se_cmd.prot_length: %u\n", req->se_cmd.prot_length);
+#endif
}
- cookie = submit_bio(rw, bio);
+ ios->se_dev = dev;
+ ios->iomem = iomem;
+ ios->t_comp_func = &nvmet_complete_ios;
- blk_poll(bdev_get_queue(req->ns->bdev), cookie);
-#endif
+ rc = sbc_ops->execute_rw(ios, iomem->t_data_sg, iomem->t_data_nents,
+ ios->data_direction, fua_write,
+ &nvmet_complete_ios);
}
static void nvmet_execute_flush(struct nvmet_req *req)
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index af616d0..a3ab4fb 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -25,6 +25,7 @@
#include <linux/configfs.h>
#include <linux/rcupdate.h>
#include <linux/blkdev.h>
+#include <target/target_core_base.h>
#define NVMET_ASYNC_EVENTS 4
#define NVMET_ERROR_LOG_SLOTS 128
@@ -262,6 +263,12 @@ struct nvmet_req {
int sg_cnt;
size_t data_len;
+ struct scatterlist *prot_sg;
+ int prot_sg_cnt;
+
+ struct target_iostate t_iostate;
+ struct target_iomem t_iomem;
+
struct nvmet_port *port;
void (*execute)(struct nvmet_req *req);
--
1.9.1
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