Commit d5eff33e authored by Chaitanya Kulkarni's avatar Chaitanya Kulkarni Committed by Christoph Hellwig

nvmet: add simple file backed ns support

This patch adds simple file backed namespace support for NVMeOF target.

The new file io-cmd-file.c is responsible for handling the code for I/O
commands when ns is file backed. Also, we introduce mempools based slow
path using sync I/Os for file backed ns to ensure forward progress under
reclaim.

The old block device based implementation is moved to io-cmd-bdev.c and
use a "nvmet_bdev_" symbol prefix.  The enable/disable calls are also
move into the respective files.
Signed-off-by: default avatarChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
[hch: updated changelog, fixed double req->ns lookup in bdev case]
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 618cff42
......@@ -6,8 +6,8 @@ obj-$(CONFIG_NVME_TARGET_RDMA) += nvmet-rdma.o
obj-$(CONFIG_NVME_TARGET_FC) += nvmet-fc.o
obj-$(CONFIG_NVME_TARGET_FCLOOP) += nvme-fcloop.o
nvmet-y += core.o configfs.o admin-cmd.o io-cmd.o fabrics-cmd.o \
discovery.o
nvmet-y += core.o configfs.o admin-cmd.o fabrics-cmd.o \
discovery.o io-cmd-file.o io-cmd-bdev.o
nvme-loop-y += loop.o
nvmet-rdma-y += rdma.o
nvmet-fc-y += fc.o
......
......@@ -45,6 +45,10 @@ static u16 nvmet_get_smart_log_nsid(struct nvmet_req *req,
return NVME_SC_INVALID_NS;
}
/* we don't have the right data for file backed ns */
if (!ns->bdev)
goto out;
host_reads = part_stat_read(ns->bdev->bd_part, ios[READ]);
data_units_read = part_stat_read(ns->bdev->bd_part, sectors[READ]);
host_writes = part_stat_read(ns->bdev->bd_part, ios[WRITE]);
......@@ -54,6 +58,7 @@ static u16 nvmet_get_smart_log_nsid(struct nvmet_req *req,
put_unaligned_le64(data_units_read, &slog->data_units_read[0]);
put_unaligned_le64(host_writes, &slog->host_writes[0]);
put_unaligned_le64(data_units_written, &slog->data_units_written[0]);
out:
nvmet_put_namespace(ns);
return NVME_SC_SUCCESS;
......@@ -71,6 +76,9 @@ static u16 nvmet_get_smart_log_all(struct nvmet_req *req,
rcu_read_lock();
list_for_each_entry_rcu(ns, &ctrl->subsys->namespaces, dev_link) {
/* we don't have the right data for file backed ns */
if (!ns->bdev)
continue;
host_reads += part_stat_read(ns->bdev->bd_part, ios[READ]);
data_units_read +=
part_stat_read(ns->bdev->bd_part, sectors[READ]);
......
......@@ -271,6 +271,12 @@ void nvmet_put_namespace(struct nvmet_ns *ns)
percpu_ref_put(&ns->ref);
}
static void nvmet_ns_dev_disable(struct nvmet_ns *ns)
{
nvmet_bdev_ns_disable(ns);
nvmet_file_ns_disable(ns);
}
int nvmet_ns_enable(struct nvmet_ns *ns)
{
struct nvmet_subsys *subsys = ns->subsys;
......@@ -281,23 +287,16 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
if (ns->enabled)
goto out_unlock;
ns->bdev = blkdev_get_by_path(ns->device_path, FMODE_READ | FMODE_WRITE,
NULL);
if (IS_ERR(ns->bdev)) {
pr_err("failed to open block device %s: (%ld)\n",
ns->device_path, PTR_ERR(ns->bdev));
ret = PTR_ERR(ns->bdev);
ns->bdev = NULL;
ret = nvmet_bdev_ns_enable(ns);
if (ret)
ret = nvmet_file_ns_enable(ns);
if (ret)
goto out_unlock;
}
ns->size = i_size_read(ns->bdev->bd_inode);
ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
ret = percpu_ref_init(&ns->ref, nvmet_destroy_namespace,
0, GFP_KERNEL);
if (ret)
goto out_blkdev_put;
goto out_dev_put;
if (ns->nsid > subsys->max_nsid)
subsys->max_nsid = ns->nsid;
......@@ -328,9 +327,8 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
out_unlock:
mutex_unlock(&subsys->lock);
return ret;
out_blkdev_put:
blkdev_put(ns->bdev, FMODE_WRITE|FMODE_READ);
ns->bdev = NULL;
out_dev_put:
nvmet_ns_dev_disable(ns);
goto out_unlock;
}
......@@ -366,8 +364,7 @@ void nvmet_ns_disable(struct nvmet_ns *ns)
list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry)
nvmet_add_async_event(ctrl, NVME_AER_TYPE_NOTICE, 0, 0);
if (ns->bdev)
blkdev_put(ns->bdev, FMODE_WRITE|FMODE_READ);
nvmet_ns_dev_disable(ns);
out_unlock:
mutex_unlock(&subsys->lock);
}
......@@ -499,6 +496,25 @@ int nvmet_sq_init(struct nvmet_sq *sq)
}
EXPORT_SYMBOL_GPL(nvmet_sq_init);
static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
{
struct nvme_command *cmd = req->cmd;
u16 ret;
ret = nvmet_check_ctrl_status(req, cmd);
if (unlikely(ret))
return ret;
req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
if (unlikely(!req->ns))
return NVME_SC_INVALID_NS | NVME_SC_DNR;
if (req->ns->file)
return nvmet_file_parse_io_cmd(req);
else
return nvmet_bdev_parse_io_cmd(req);
}
bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
struct nvmet_sq *sq, const struct nvmet_fabrics_ops *ops)
{
......
......@@ -16,6 +16,34 @@
#include <linux/module.h>
#include "nvmet.h"
int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
{
int ret;
ns->bdev = blkdev_get_by_path(ns->device_path,
FMODE_READ | FMODE_WRITE, NULL);
if (IS_ERR(ns->bdev)) {
ret = PTR_ERR(ns->bdev);
if (ret != -ENOTBLK) {
pr_err("failed to open block device %s: (%ld)\n",
ns->device_path, PTR_ERR(ns->bdev));
}
ns->bdev = NULL;
return ret;
}
ns->size = i_size_read(ns->bdev->bd_inode);
ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
return 0;
}
void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
{
if (ns->bdev) {
blkdev_put(ns->bdev, FMODE_WRITE | FMODE_READ);
ns->bdev = NULL;
}
}
static void nvmet_bio_done(struct bio *bio)
{
struct nvmet_req *req = bio->bi_private;
......@@ -23,20 +51,14 @@ static void nvmet_bio_done(struct bio *bio)
nvmet_req_complete(req,
bio->bi_status ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
if (bio != &req->inline_bio)
if (bio != &req->b.inline_bio)
bio_put(bio);
}
static inline u32 nvmet_rw_len(struct nvmet_req *req)
{
return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
req->ns->blksize_shift;
}
static void nvmet_execute_rw(struct nvmet_req *req)
static void nvmet_bdev_execute_rw(struct nvmet_req *req)
{
int sg_cnt = req->sg_cnt;
struct bio *bio = &req->inline_bio;
struct bio *bio = &req->b.inline_bio;
struct scatterlist *sg;
sector_t sector;
blk_qc_t cookie;
......@@ -89,9 +111,9 @@ static void nvmet_execute_rw(struct nvmet_req *req)
blk_poll(bdev_get_queue(req->ns->bdev), cookie);
}
static void nvmet_execute_flush(struct nvmet_req *req)
static void nvmet_bdev_execute_flush(struct nvmet_req *req)
{
struct bio *bio = &req->inline_bio;
struct bio *bio = &req->b.inline_bio;
bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
bio_set_dev(bio, req->ns->bdev);
......@@ -102,7 +124,7 @@ static void nvmet_execute_flush(struct nvmet_req *req)
submit_bio(bio);
}
static u16 nvmet_discard_range(struct nvmet_ns *ns,
static u16 nvmet_bdev_discard_range(struct nvmet_ns *ns,
struct nvme_dsm_range *range, struct bio **bio)
{
int ret;
......@@ -116,7 +138,7 @@ static u16 nvmet_discard_range(struct nvmet_ns *ns,
return 0;
}
static void nvmet_execute_discard(struct nvmet_req *req)
static void nvmet_bdev_execute_discard(struct nvmet_req *req)
{
struct nvme_dsm_range range;
struct bio *bio = NULL;
......@@ -129,7 +151,7 @@ static void nvmet_execute_discard(struct nvmet_req *req)
if (status)
break;
status = nvmet_discard_range(req->ns, &range, &bio);
status = nvmet_bdev_discard_range(req->ns, &range, &bio);
if (status)
break;
}
......@@ -148,11 +170,11 @@ static void nvmet_execute_discard(struct nvmet_req *req)
}
}
static void nvmet_execute_dsm(struct nvmet_req *req)
static void nvmet_bdev_execute_dsm(struct nvmet_req *req)
{
switch (le32_to_cpu(req->cmd->dsm.attributes)) {
case NVME_DSMGMT_AD:
nvmet_execute_discard(req);
nvmet_bdev_execute_discard(req);
return;
case NVME_DSMGMT_IDR:
case NVME_DSMGMT_IDW:
......@@ -163,7 +185,7 @@ static void nvmet_execute_dsm(struct nvmet_req *req)
}
}
static void nvmet_execute_write_zeroes(struct nvmet_req *req)
static void nvmet_bdev_execute_write_zeroes(struct nvmet_req *req)
{
struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
struct bio *bio = NULL;
......@@ -189,36 +211,27 @@ static void nvmet_execute_write_zeroes(struct nvmet_req *req)
}
}
u16 nvmet_parse_io_cmd(struct nvmet_req *req)
u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req)
{
struct nvme_command *cmd = req->cmd;
u16 ret;
ret = nvmet_check_ctrl_status(req, cmd);
if (unlikely(ret))
return ret;
req->ns = nvmet_find_namespace(req->sq->ctrl, cmd->rw.nsid);
if (unlikely(!req->ns))
return NVME_SC_INVALID_NS | NVME_SC_DNR;
switch (cmd->common.opcode) {
case nvme_cmd_read:
case nvme_cmd_write:
req->execute = nvmet_execute_rw;
req->execute = nvmet_bdev_execute_rw;
req->data_len = nvmet_rw_len(req);
return 0;
case nvme_cmd_flush:
req->execute = nvmet_execute_flush;
req->execute = nvmet_bdev_execute_flush;
req->data_len = 0;
return 0;
case nvme_cmd_dsm:
req->execute = nvmet_execute_dsm;
req->execute = nvmet_bdev_execute_dsm;
req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
sizeof(struct nvme_dsm_range);
return 0;
case nvme_cmd_write_zeroes:
req->execute = nvmet_execute_write_zeroes;
req->execute = nvmet_bdev_execute_write_zeroes;
return 0;
default:
pr_err("unhandled cmd %d on qid %d\n", cmd->common.opcode,
......
// SPDX-License-Identifier: GPL-2.0
/*
* NVMe Over Fabrics Target File I/O commands implementation.
* Copyright (c) 2017-2018 Western Digital Corporation or its
* affiliates.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/uio.h>
#include <linux/falloc.h>
#include <linux/file.h>
#include "nvmet.h"
#define NVMET_MAX_MPOOL_BVEC 16
#define NVMET_MIN_MPOOL_OBJ 16
void nvmet_file_ns_disable(struct nvmet_ns *ns)
{
if (ns->file) {
mempool_destroy(ns->bvec_pool);
ns->bvec_pool = NULL;
kmem_cache_destroy(ns->bvec_cache);
ns->bvec_cache = NULL;
fput(ns->file);
ns->file = NULL;
}
}
int nvmet_file_ns_enable(struct nvmet_ns *ns)
{
int ret;
struct kstat stat;
ns->file = filp_open(ns->device_path,
O_RDWR | O_LARGEFILE | O_DIRECT, 0);
if (IS_ERR(ns->file)) {
pr_err("failed to open file %s: (%ld)\n",
ns->device_path, PTR_ERR(ns->bdev));
return PTR_ERR(ns->file);
}
ret = vfs_getattr(&ns->file->f_path,
&stat, STATX_SIZE, AT_STATX_FORCE_SYNC);
if (ret)
goto err;
ns->size = stat.size;
ns->blksize_shift = file_inode(ns->file)->i_blkbits;
ns->bvec_cache = kmem_cache_create("nvmet-bvec",
NVMET_MAX_MPOOL_BVEC * sizeof(struct bio_vec),
0, SLAB_HWCACHE_ALIGN, NULL);
if (!ns->bvec_cache)
goto err;
ns->bvec_pool = mempool_create(NVMET_MIN_MPOOL_OBJ, mempool_alloc_slab,
mempool_free_slab, ns->bvec_cache);
if (!ns->bvec_pool)
goto err;
return ret;
err:
ns->size = 0;
ns->blksize_shift = 0;
nvmet_file_ns_disable(ns);
return ret;
}
static void nvmet_file_init_bvec(struct bio_vec *bv, struct sg_page_iter *iter)
{
bv->bv_page = sg_page_iter_page(iter);
bv->bv_offset = iter->sg->offset;
bv->bv_len = PAGE_SIZE - iter->sg->offset;
}
static ssize_t nvmet_file_submit_bvec(struct nvmet_req *req, loff_t pos,
unsigned long nr_segs, size_t count)
{
struct kiocb *iocb = &req->f.iocb;
ssize_t (*call_iter)(struct kiocb *iocb, struct iov_iter *iter);
struct iov_iter iter;
int ki_flags = 0, rw;
ssize_t ret;
if (req->cmd->rw.opcode == nvme_cmd_write) {
if (req->cmd->rw.control & cpu_to_le16(NVME_RW_FUA))
ki_flags = IOCB_DSYNC;
call_iter = req->ns->file->f_op->write_iter;
rw = WRITE;
} else {
call_iter = req->ns->file->f_op->read_iter;
rw = READ;
}
iov_iter_bvec(&iter, ITER_BVEC | rw, req->f.bvec, nr_segs, count);
iocb->ki_pos = pos;
iocb->ki_filp = req->ns->file;
iocb->ki_flags = IOCB_DIRECT | ki_flags;
ret = call_iter(iocb, &iter);
if (ret != -EIOCBQUEUED && iocb->ki_complete)
iocb->ki_complete(iocb, ret, 0);
return ret;
}
static void nvmet_file_io_done(struct kiocb *iocb, long ret, long ret2)
{
struct nvmet_req *req = container_of(iocb, struct nvmet_req, f.iocb);
if (req->f.bvec != req->inline_bvec) {
if (likely(req->f.mpool_alloc == false))
kfree(req->f.bvec);
else
mempool_free(req->f.bvec, req->ns->bvec_pool);
}
nvmet_req_complete(req, ret != req->data_len ?
NVME_SC_INTERNAL | NVME_SC_DNR : 0);
}
static void nvmet_file_execute_rw(struct nvmet_req *req)
{
ssize_t nr_bvec = DIV_ROUND_UP(req->data_len, PAGE_SIZE);
struct sg_page_iter sg_pg_iter;
unsigned long bv_cnt = 0;
bool is_sync = false;
size_t len = 0, total_len = 0;
ssize_t ret = 0;
loff_t pos;
if (!req->sg_cnt || !nr_bvec) {
nvmet_req_complete(req, 0);
return;
}
if (nr_bvec > NVMET_MAX_INLINE_BIOVEC)
req->f.bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec),
GFP_KERNEL);
else
req->f.bvec = req->inline_bvec;
req->f.mpool_alloc = false;
if (unlikely(!req->f.bvec)) {
/* fallback under memory pressure */
req->f.bvec = mempool_alloc(req->ns->bvec_pool, GFP_KERNEL);
req->f.mpool_alloc = true;
if (nr_bvec > NVMET_MAX_MPOOL_BVEC)
is_sync = true;
}
pos = le64_to_cpu(req->cmd->rw.slba) << req->ns->blksize_shift;
memset(&req->f.iocb, 0, sizeof(struct kiocb));
for_each_sg_page(req->sg, &sg_pg_iter, req->sg_cnt, 0) {
nvmet_file_init_bvec(&req->f.bvec[bv_cnt], &sg_pg_iter);
len += req->f.bvec[bv_cnt].bv_len;
total_len += req->f.bvec[bv_cnt].bv_len;
bv_cnt++;
WARN_ON_ONCE((nr_bvec - 1) < 0);
if (unlikely(is_sync) &&
(nr_bvec - 1 == 0 || bv_cnt == NVMET_MAX_MPOOL_BVEC)) {
ret = nvmet_file_submit_bvec(req, pos, bv_cnt, len);
if (ret < 0)
goto out;
pos += len;
bv_cnt = 0;
len = 0;
}
nr_bvec--;
}
if (WARN_ON_ONCE(total_len != req->data_len))
ret = -EIO;
out:
if (unlikely(is_sync || ret)) {
nvmet_file_io_done(&req->f.iocb, ret < 0 ? ret : total_len, 0);
return;
}
req->f.iocb.ki_complete = nvmet_file_io_done;
nvmet_file_submit_bvec(req, pos, bv_cnt, total_len);
}
static void nvmet_file_flush_work(struct work_struct *w)
{
struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
int ret;
ret = vfs_fsync(req->ns->file, 1);
nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
}
static void nvmet_file_execute_flush(struct nvmet_req *req)
{
INIT_WORK(&req->f.work, nvmet_file_flush_work);
schedule_work(&req->f.work);
}
static void nvmet_file_execute_discard(struct nvmet_req *req)
{
int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
struct nvme_dsm_range range;
loff_t offset;
loff_t len;
int i, ret;
for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
if (nvmet_copy_from_sgl(req, i * sizeof(range), &range,
sizeof(range)))
break;
offset = le64_to_cpu(range.slba) << req->ns->blksize_shift;
len = le32_to_cpu(range.nlb) << req->ns->blksize_shift;
ret = vfs_fallocate(req->ns->file, mode, offset, len);
if (ret)
break;
}
nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
}
static void nvmet_file_dsm_work(struct work_struct *w)
{
struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
switch (le32_to_cpu(req->cmd->dsm.attributes)) {
case NVME_DSMGMT_AD:
nvmet_file_execute_discard(req);
return;
case NVME_DSMGMT_IDR:
case NVME_DSMGMT_IDW:
default:
/* Not supported yet */
nvmet_req_complete(req, 0);
return;
}
}
static void nvmet_file_execute_dsm(struct nvmet_req *req)
{
INIT_WORK(&req->f.work, nvmet_file_dsm_work);
schedule_work(&req->f.work);
}
static void nvmet_file_write_zeroes_work(struct work_struct *w)
{
struct nvmet_req *req = container_of(w, struct nvmet_req, f.work);
struct nvme_write_zeroes_cmd *write_zeroes = &req->cmd->write_zeroes;
int mode = FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE;
loff_t offset;
loff_t len;
int ret;
offset = le64_to_cpu(write_zeroes->slba) << req->ns->blksize_shift;
len = (((sector_t)le16_to_cpu(write_zeroes->length) + 1) <<
req->ns->blksize_shift);
ret = vfs_fallocate(req->ns->file, mode, offset, len);
nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
}
static void nvmet_file_execute_write_zeroes(struct nvmet_req *req)
{
INIT_WORK(&req->f.work, nvmet_file_write_zeroes_work);
schedule_work(&req->f.work);
}
u16 nvmet_file_parse_io_cmd(struct nvmet_req *req)
{
struct nvme_command *cmd = req->cmd;
switch (cmd->common.opcode) {
case nvme_cmd_read:
case nvme_cmd_write:
req->execute = nvmet_file_execute_rw;
req->data_len = nvmet_rw_len(req);
return 0;
case nvme_cmd_flush:
req->execute = nvmet_file_execute_flush;
req->data_len = 0;
return 0;
case nvme_cmd_dsm:
req->execute = nvmet_file_execute_dsm;
req->data_len = (le32_to_cpu(cmd->dsm.nr) + 1) *
sizeof(struct nvme_dsm_range);
return 0;
case nvme_cmd_write_zeroes:
req->execute = nvmet_file_execute_write_zeroes;
req->data_len = 0;
return 0;
default:
pr_err("unhandled cmd for file ns %d on qid %d\n",
cmd->common.opcode, req->sq->qid);
return NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
}
}
......@@ -43,6 +43,7 @@ struct nvmet_ns {
struct list_head dev_link;
struct percpu_ref ref;
struct block_device *bdev;
struct file *file;
u32 nsid;
u32 blksize_shift;
loff_t size;
......@@ -57,6 +58,8 @@ struct nvmet_ns {
struct config_group group;
struct completion disable_done;
mempool_t *bvec_pool;
struct kmem_cache *bvec_cache;
};
static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
......@@ -222,8 +225,18 @@ struct nvmet_req {
struct nvmet_cq *cq;
struct nvmet_ns *ns;
struct scatterlist *sg;
struct bio inline_bio;
struct bio_vec inline_bvec[NVMET_MAX_INLINE_BIOVEC];
union {
struct {
struct bio inline_bio;
} b;
struct {
bool mpool_alloc;
struct kiocb iocb;
struct bio_vec *bvec;
struct work_struct work;
} f;
};
int sg_cnt;
/* data length as parsed from the command: */
size_t data_len;
......@@ -263,7 +276,8 @@ struct nvmet_async_event {
};
u16 nvmet_parse_connect_cmd(struct nvmet_req *req);
u16 nvmet_parse_io_cmd(struct nvmet_req *req);
u16 nvmet_bdev_parse_io_cmd(struct nvmet_req *req);
u16 nvmet_file_parse_io_cmd(struct nvmet_req *req);
u16 nvmet_parse_admin_cmd(struct nvmet_req *req);
u16 nvmet_parse_discovery_cmd(struct nvmet_req *req);
u16 nvmet_parse_fabrics_cmd(struct nvmet_req *req);
......@@ -338,4 +352,14 @@ extern struct rw_semaphore nvmet_config_sem;
bool nvmet_host_allowed(struct nvmet_req *req, struct nvmet_subsys *subsys,
const char *hostnqn);
int nvmet_bdev_ns_enable(struct nvmet_ns *ns);
int nvmet_file_ns_enable(struct nvmet_ns *ns);
void nvmet_bdev_ns_disable(struct nvmet_ns *ns);
void nvmet_file_ns_disable(struct nvmet_ns *ns);
static inline u32 nvmet_rw_len(struct nvmet_req *req)
{
return ((u32)le16_to_cpu(req->cmd->rw.length) + 1) <<
req->ns->blksize_shift;
}
#endif /* _NVMET_H */
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