* [PATCH for-next v9 0/7] fixed-buffer for uring-cmd/passthru
[not found] <CGME20220925203314epcas5p2a075d1026db3a46df09a4b67108109b4@epcas5p2.samsung.com>
@ 2022-09-25 20:22 ` Kanchan Joshi
[not found] ` <CGME20220925203320epcas5p28fcc3c9ff8669c56213547725ea71001@epcas5p2.samsung.com>
` (6 more replies)
0 siblings, 7 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:22 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi
Hi
uring-cmd lacks the ability to leverage the pre-registered buffers.
This series adds that support in uring-cmd, and plumbs nvme passthrough
to work with it.
Patch 3 and 4 contains a bunch of general nvme cleanups, which got added
along the iterations.
Using registered-buffers showed 22-26% hike in peak IOPS (v8,in Jens setup).
Changes since v8:
- Split some patches further; now 7 patches rather than 5 (Christoph)
- Applied a bunch of other suggested cleanups (Christoph)
Changes since v7:
- Patch 3: added many cleanups/refactoring suggested by Christoph
- Patch 4: added copying-pages fallback for bounce-buffer/dma-alignment case
(Christoph)
Changes since v6:
- Patch 1: fix warning for io_uring_cmd_import_fixed (robot)
-
Changes since v5:
- Patch 4: newly addd, to split a nvme function into two
- Patch 3: folded cleanups in bio_map_user_iov (Chaitanya, Pankaj)
- Rebase to latest for-next
Changes since v4:
- Patch 1, 2: folded all review comments of Jens
Changes since v3:
- uring_cmd_flags, change from u16 to u32 (Jens)
- patch 3, add another helper to reduce code-duplication (Jens)
Changes since v2:
- Kill the new opcode, add a flag instead (Pavel)
- Fix standalone build issue with patch 1 (Pavel)
Changes since v1:
- Fix a naming issue for an exported helper
Anuj Gupta (2):
io_uring: add io_uring_cmd_import_fixed
io_uring: introduce fixed buffer support for io_uring_cmd
Kanchan Joshi (5):
nvme: refactor nvme_add_user_metadata
nvme: refactor nvme_alloc_request
block: factor out bio_map_get helper
block: introduce helper to map bvec iterator
nvme: wire up fixed buffer support for nvme passthrough
block/blk-map.c | 111 ++++++++++++++++++++---
drivers/nvme/host/ioctl.c | 160 ++++++++++++++++++++--------------
include/linux/blk-mq.h | 1 +
include/linux/io_uring.h | 10 ++-
include/uapi/linux/io_uring.h | 9 ++
io_uring/uring_cmd.c | 26 +++++-
6 files changed, 241 insertions(+), 76 deletions(-)
--
2.25.1
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH for-next v9 1/7] io_uring: add io_uring_cmd_import_fixed
[not found] ` <CGME20220925203320epcas5p28fcc3c9ff8669c56213547725ea71001@epcas5p2.samsung.com>
@ 2022-09-25 20:22 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:22 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Anuj Gupta,
Kanchan Joshi
From: Anuj Gupta <[email protected]>
This is a new helper that callers can use to obtain a bvec iterator for
the previously mapped buffer. This is preparatory work to enable
fixed-buffer support for io_uring_cmd.
Signed-off-by: Anuj Gupta <[email protected]>
Signed-off-by: Kanchan Joshi <[email protected]>
---
include/linux/io_uring.h | 8 ++++++++
io_uring/uring_cmd.c | 10 ++++++++++
2 files changed, 18 insertions(+)
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 58676c0a398f..1dbf51115c30 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -4,6 +4,7 @@
#include <linux/sched.h>
#include <linux/xarray.h>
+#include <uapi/linux/io_uring.h>
enum io_uring_cmd_flags {
IO_URING_F_COMPLETE_DEFER = 1,
@@ -32,6 +33,8 @@ struct io_uring_cmd {
};
#if defined(CONFIG_IO_URING)
+int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
+ struct iov_iter *iter, void *ioucmd);
void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret, ssize_t res2);
void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
void (*task_work_cb)(struct io_uring_cmd *));
@@ -59,6 +62,11 @@ static inline void io_uring_free(struct task_struct *tsk)
__io_uring_free(tsk);
}
#else
+static int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
+ struct iov_iter *iter, void *ioucmd)
+{
+ return -EOPNOTSUPP;
+}
static inline void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret,
ssize_t ret2)
{
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index f3ed61e9bd0f..6a6d69523d75 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -8,6 +8,7 @@
#include <uapi/linux/io_uring.h>
#include "io_uring.h"
+#include "rsrc.h"
#include "uring_cmd.h"
static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
@@ -129,3 +130,12 @@ int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
return IOU_ISSUE_SKIP_COMPLETE;
}
+
+int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
+ struct iov_iter *iter, void *ioucmd)
+{
+ struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
+
+ return io_import_fixed(rw, iter, req->imu, ubuf, len);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 2/7] io_uring: introduce fixed buffer support for io_uring_cmd
[not found] ` <CGME20220925203325epcas5p1e4e89d414aa7a268a6e526d3c7c2261c@epcas5p1.samsung.com>
@ 2022-09-25 20:22 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:22 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Anuj Gupta,
Kanchan Joshi
From: Anuj Gupta <[email protected]>
Add IORING_URING_CMD_FIXED flag that is to be used for sending io_uring
command with previously registered buffers. User-space passes the buffer
index in sqe->buf_index, same as done in read/write variants that uses
fixed buffers.
Signed-off-by: Anuj Gupta <[email protected]>
Signed-off-by: Kanchan Joshi <[email protected]>
---
include/linux/io_uring.h | 2 +-
include/uapi/linux/io_uring.h | 9 +++++++++
io_uring/uring_cmd.c | 16 +++++++++++++++-
3 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h
index 1dbf51115c30..e10c5cc81082 100644
--- a/include/linux/io_uring.h
+++ b/include/linux/io_uring.h
@@ -28,7 +28,7 @@ struct io_uring_cmd {
void *cookie;
};
u32 cmd_op;
- u32 pad;
+ u32 flags;
u8 pdu[32]; /* available inline for free use */
};
diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index 92f29d9505a6..ab7458033ee3 100644
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -56,6 +56,7 @@ struct io_uring_sqe {
__u32 hardlink_flags;
__u32 xattr_flags;
__u32 msg_ring_flags;
+ __u32 uring_cmd_flags;
};
__u64 user_data; /* data to be passed back at completion time */
/* pack this to avoid bogus arm OABI complaints */
@@ -219,6 +220,14 @@ enum io_uring_op {
IORING_OP_LAST,
};
+/*
+ * sqe->uring_cmd_flags
+ * IORING_URING_CMD_FIXED use registered buffer; pass thig flag
+ * along with setting sqe->buf_index.
+ */
+#define IORING_URING_CMD_FIXED (1U << 0)
+
+
/*
* sqe->fsync_flags
*/
diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index 6a6d69523d75..faefa9f6f259 100644
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -4,6 +4,7 @@
#include <linux/file.h>
#include <linux/io_uring.h>
#include <linux/security.h>
+#include <linux/nospec.h>
#include <uapi/linux/io_uring.h>
@@ -77,8 +78,21 @@ int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
- if (sqe->rw_flags || sqe->__pad1)
+ if (sqe->__pad1)
return -EINVAL;
+
+ ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
+ if (ioucmd->flags & IORING_URING_CMD_FIXED) {
+ struct io_ring_ctx *ctx = req->ctx;
+ u16 index;
+
+ req->buf_index = READ_ONCE(sqe->buf_index);
+ if (unlikely(req->buf_index >= ctx->nr_user_bufs))
+ return -EFAULT;
+ index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
+ req->imu = ctx->user_bufs[index];
+ io_req_set_rsrc_node(req, ctx, 0);
+ }
ioucmd->cmd = sqe->cmd;
ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
return 0;
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 3/7] nvme: refactor nvme_add_user_metadata
[not found] ` <CGME20220925203328epcas5p1872214ededaf3b75762dcb5af15199da@epcas5p1.samsung.com>
@ 2022-09-25 20:23 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:23 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi
Pass struct request rather than bio. It helps to kill a parameter, and
some processing clean-up too.
Signed-off-by: Kanchan Joshi <[email protected]>
---
drivers/nvme/host/ioctl.c | 23 +++++++++++++----------
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 548aca8b5b9f..8f8435b55b95 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -20,19 +20,20 @@ static void __user *nvme_to_user_ptr(uintptr_t ptrval)
return (void __user *)ptrval;
}
-static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
- unsigned len, u32 seed, bool write)
+static void *nvme_add_user_metadata(struct request *req, void __user *ubuf,
+ unsigned len, u32 seed)
{
struct bio_integrity_payload *bip;
int ret = -ENOMEM;
void *buf;
+ struct bio *bio = req->bio;
buf = kmalloc(len, GFP_KERNEL);
if (!buf)
goto out;
ret = -EFAULT;
- if (write && copy_from_user(buf, ubuf, len))
+ if ((req_op(req) == REQ_OP_DRV_OUT) && copy_from_user(buf, ubuf, len))
goto out_free_meta;
bip = bio_integrity_alloc(bio, GFP_KERNEL, 1);
@@ -45,9 +46,13 @@ static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf,
bip->bip_iter.bi_sector = seed;
ret = bio_integrity_add_page(bio, virt_to_page(buf), len,
offset_in_page(buf));
- if (ret == len)
- return buf;
- ret = -ENOMEM;
+ if (ret != len) {
+ ret = -ENOMEM;
+ goto out_free_meta;
+ }
+
+ req->cmd_flags |= REQ_INTEGRITY;
+ return buf;
out_free_meta:
kfree(buf);
out:
@@ -70,7 +75,6 @@ static struct request *nvme_alloc_user_request(struct request_queue *q,
u32 meta_seed, void **metap, unsigned timeout, bool vec,
blk_opf_t rq_flags, blk_mq_req_flags_t blk_flags)
{
- bool write = nvme_is_write(cmd);
struct nvme_ns *ns = q->queuedata;
struct block_device *bdev = ns ? ns->disk->part0 : NULL;
struct request *req;
@@ -110,13 +114,12 @@ static struct request *nvme_alloc_user_request(struct request_queue *q,
if (bdev)
bio_set_dev(bio, bdev);
if (bdev && meta_buffer && meta_len) {
- meta = nvme_add_user_metadata(bio, meta_buffer, meta_len,
- meta_seed, write);
+ meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
+ meta_seed);
if (IS_ERR(meta)) {
ret = PTR_ERR(meta);
goto out_unmap;
}
- req->cmd_flags |= REQ_INTEGRITY;
*metap = meta;
}
}
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 4/7] nvme: refactor nvme_alloc_request
[not found] ` <CGME20220925203330epcas5p20c712fa919a4cc2a5ec3bbaa94bb72ca@epcas5p2.samsung.com>
@ 2022-09-25 20:23 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:23 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi
nvme_alloc_alloc_request expects a large number of parameters.
Split this out into two functions to reduce number of parameters.
First one retains the name nvme_alloc_request, while second one is
named nvme_map_user_request.
Signed-off-by: Kanchan Joshi <[email protected]>
---
drivers/nvme/host/ioctl.c | 121 ++++++++++++++++++++++----------------
1 file changed, 69 insertions(+), 52 deletions(-)
diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 8f8435b55b95..b9f17dc87de9 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -70,68 +70,69 @@ static int nvme_finish_user_metadata(struct request *req, void __user *ubuf,
}
static struct request *nvme_alloc_user_request(struct request_queue *q,
- struct nvme_command *cmd, void __user *ubuffer,
- unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
- u32 meta_seed, void **metap, unsigned timeout, bool vec,
- blk_opf_t rq_flags, blk_mq_req_flags_t blk_flags)
+ struct nvme_command *cmd, blk_opf_t rq_flags,
+ blk_mq_req_flags_t blk_flags)
{
- struct nvme_ns *ns = q->queuedata;
- struct block_device *bdev = ns ? ns->disk->part0 : NULL;
struct request *req;
- struct bio *bio = NULL;
- void *meta = NULL;
- int ret;
req = blk_mq_alloc_request(q, nvme_req_op(cmd) | rq_flags, blk_flags);
if (IS_ERR(req))
return req;
nvme_init_request(req, cmd);
-
- if (timeout)
- req->timeout = timeout;
nvme_req(req)->flags |= NVME_REQ_USERCMD;
+ return req;
+}
- if (ubuffer && bufflen) {
- if (!vec)
- ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
- GFP_KERNEL);
- else {
- struct iovec fast_iov[UIO_FASTIOV];
- struct iovec *iov = fast_iov;
- struct iov_iter iter;
-
- ret = import_iovec(rq_data_dir(req), ubuffer, bufflen,
- UIO_FASTIOV, &iov, &iter);
- if (ret < 0)
- goto out;
- ret = blk_rq_map_user_iov(q, req, NULL, &iter,
- GFP_KERNEL);
- kfree(iov);
- }
- if (ret)
+static int nvme_map_user_request(struct request *req, void __user *ubuffer,
+ unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
+ u32 meta_seed, void **metap, bool vec)
+{
+ struct request_queue *q = req->q;
+ struct nvme_ns *ns = q->queuedata;
+ struct block_device *bdev = ns ? ns->disk->part0 : NULL;
+ struct bio *bio = NULL;
+ void *meta = NULL;
+ int ret;
+
+ if (!vec)
+ ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
+ GFP_KERNEL);
+ else {
+ struct iovec fast_iov[UIO_FASTIOV];
+ struct iovec *iov = fast_iov;
+ struct iov_iter iter;
+
+ ret = import_iovec(rq_data_dir(req), ubuffer, bufflen,
+ UIO_FASTIOV, &iov, &iter);
+ if (ret < 0)
goto out;
- bio = req->bio;
- if (bdev)
- bio_set_dev(bio, bdev);
- if (bdev && meta_buffer && meta_len) {
- meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
- meta_seed);
- if (IS_ERR(meta)) {
- ret = PTR_ERR(meta);
- goto out_unmap;
- }
- *metap = meta;
+
+ ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
+ kfree(iov);
+ }
+ if (ret)
+ goto out;
+ bio = req->bio;
+ if (bdev)
+ bio_set_dev(bio, bdev);
+
+ if (bdev && meta_buffer && meta_len) {
+ meta = nvme_add_user_metadata(req, meta_buffer, meta_len,
+ meta_seed);
+ if (IS_ERR(meta)) {
+ ret = PTR_ERR(meta);
+ goto out_unmap;
}
+ *metap = meta;
}
- return req;
+ return ret;
out_unmap:
if (bio)
blk_rq_unmap_user(bio);
out:
- blk_mq_free_request(req);
- return ERR_PTR(ret);
+ return ret;
}
static int nvme_submit_user_cmd(struct request_queue *q,
@@ -144,13 +145,19 @@ static int nvme_submit_user_cmd(struct request_queue *q,
struct bio *bio;
int ret;
- req = nvme_alloc_user_request(q, cmd, ubuffer, bufflen, meta_buffer,
- meta_len, meta_seed, &meta, timeout, vec, 0, 0);
+ req = nvme_alloc_user_request(q, cmd, 0, 0);
if (IS_ERR(req))
return PTR_ERR(req);
- bio = req->bio;
+ req->timeout = timeout;
+ if (ubuffer && bufflen) {
+ ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
+ meta_len, meta_seed, &meta, vec);
+ if (ret)
+ goto out;
+ }
+ bio = req->bio;
ret = nvme_execute_passthru_rq(req);
if (result)
@@ -160,6 +167,7 @@ static int nvme_submit_user_cmd(struct request_queue *q,
meta_len, ret);
if (bio)
blk_rq_unmap_user(bio);
+out:
blk_mq_free_request(req);
return ret;
}
@@ -421,6 +429,7 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
blk_opf_t rq_flags = 0;
blk_mq_req_flags_t blk_flags = 0;
void *meta = NULL;
+ int ret;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
@@ -460,13 +469,18 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
rq_flags |= REQ_POLLED;
retry:
- req = nvme_alloc_user_request(q, &c, nvme_to_user_ptr(d.addr),
- d.data_len, nvme_to_user_ptr(d.metadata),
- d.metadata_len, 0, &meta, d.timeout_ms ?
- msecs_to_jiffies(d.timeout_ms) : 0, vec, rq_flags,
- blk_flags);
+ req = nvme_alloc_user_request(q, &c, rq_flags, blk_flags);
if (IS_ERR(req))
return PTR_ERR(req);
+ req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0;
+
+ if (d.addr && d.data_len) {
+ ret = nvme_map_user_request(req, nvme_to_user_ptr(d.addr),
+ d.data_len, nvme_to_user_ptr(d.metadata),
+ d.metadata_len, 0, &meta, vec);
+ if (ret)
+ goto out_err;
+ }
req->end_io = nvme_uring_cmd_end_io;
req->end_io_data = ioucmd;
@@ -489,6 +503,9 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
blk_execute_rq_nowait(req, false);
return -EIOCBQUEUED;
+out_err:
+ blk_mq_free_request(req);
+ return ret;
}
static bool is_ctrl_ioctl(unsigned int cmd)
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 5/7] block: factor out bio_map_get helper
[not found] ` <CGME20220925203332epcas5p3b080cce759996dec4e081f03e9ecd2f9@epcas5p3.samsung.com>
@ 2022-09-25 20:23 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:23 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi
Move bio allocation logic from bio_map_user_iov to a new helper
bio_map_get. It is named so because functionality is opposite of what is
done inside bio_map_put. This is a prep patch.
Signed-off-by: Kanchan Joshi <[email protected]>
---
block/blk-map.c | 31 +++++++++++++++++++++----------
1 file changed, 21 insertions(+), 10 deletions(-)
diff --git a/block/blk-map.c b/block/blk-map.c
index 7693f8e3c454..a7838879e28e 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -241,17 +241,10 @@ static void bio_map_put(struct bio *bio)
}
}
-static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
+static struct bio *bio_map_get(struct request *rq, unsigned int nr_vecs,
gfp_t gfp_mask)
{
- unsigned int max_sectors = queue_max_hw_sectors(rq->q);
- unsigned int nr_vecs = iov_iter_npages(iter, BIO_MAX_VECS);
struct bio *bio;
- int ret;
- int j;
-
- if (!iov_iter_count(iter))
- return -EINVAL;
if (rq->cmd_flags & REQ_POLLED) {
blk_opf_t opf = rq->cmd_flags | REQ_ALLOC_CACHE;
@@ -259,13 +252,31 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
bio = bio_alloc_bioset(NULL, nr_vecs, opf, gfp_mask,
&fs_bio_set);
if (!bio)
- return -ENOMEM;
+ return NULL;
} else {
bio = bio_kmalloc(nr_vecs, gfp_mask);
if (!bio)
- return -ENOMEM;
+ return NULL;
bio_init(bio, NULL, bio->bi_inline_vecs, nr_vecs, req_op(rq));
}
+ return bio;
+}
+
+static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
+ gfp_t gfp_mask)
+{
+ unsigned int max_sectors = queue_max_hw_sectors(rq->q);
+ unsigned int nr_vecs = iov_iter_npages(iter, BIO_MAX_VECS);
+ struct bio *bio;
+ int ret;
+ int j;
+
+ if (!iov_iter_count(iter))
+ return -EINVAL;
+
+ bio = bio_map_get(rq, nr_vecs, gfp_mask);
+ if (bio == NULL)
+ return -ENOMEM;
while (iov_iter_count(iter)) {
struct page **pages, *stack_pages[UIO_FASTIOV];
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 6/7] block: introduce helper to map bvec iterator
[not found] ` <CGME20220925203336epcas5p39e910479f992d7d9e233210e0647a6bf@epcas5p3.samsung.com>
@ 2022-09-25 20:23 ` Kanchan Joshi
2022-09-26 14:54 ` Christoph Hellwig
0 siblings, 1 reply; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:23 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi,
Anuj Gupta
Add blk_rq_map_user_bvec which maps the pages from bvec iterator into a
bio, and places the bio into the request. This helper will be used by
nvme for uring-passthrough path with pre-mapped buffers.
Signed-off-by: Kanchan Joshi <[email protected]>
Signed-off-by: Anuj Gupta <[email protected]>
---
block/blk-map.c | 80 ++++++++++++++++++++++++++++++++++++++++++
include/linux/blk-mq.h | 1 +
2 files changed, 81 insertions(+)
diff --git a/block/blk-map.c b/block/blk-map.c
index a7838879e28e..d6265d49b15b 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -622,6 +622,86 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq,
}
EXPORT_SYMBOL(blk_rq_map_user);
+/* Prepare bio for passthrough IO given an existing bvec iter */
+int blk_rq_map_user_bvec(struct request *rq, struct iov_iter *iter)
+{
+ struct request_queue *q = rq->q;
+ size_t nr_iter, nr_segs, i;
+ struct bio *bio = NULL;
+ struct bio_vec *bv, *bvecs, *bvprvp = NULL;
+ struct queue_limits *lim = &q->limits;
+ unsigned int nsegs = 0, bytes = 0;
+ bool copy = false;
+ int ret;
+ unsigned long align = q->dma_pad_mask | queue_dma_alignment(q);
+
+ /* see if we need to copy pages due to any weird situation */
+ if (blk_queue_may_bounce(q))
+ copy = true;
+ else if (iov_iter_alignment(iter) & align)
+ copy = true;
+
+ if (copy) {
+ do {
+ ret = bio_copy_user_iov(rq, NULL, iter, GFP_KERNEL);
+ if (ret) {
+ blk_rq_unmap_user(bio);
+ rq->bio = NULL;
+ break;
+ }
+ if (!bio)
+ bio = rq->bio;
+ } while (iov_iter_count(iter));
+
+ return ret;
+ }
+ /* common (non-copy) case handling */
+ nr_iter = iov_iter_count(iter);
+ nr_segs = iter->nr_segs;
+
+ if (!nr_iter || (nr_iter >> SECTOR_SHIFT) > queue_max_hw_sectors(q))
+ return -EINVAL;
+ if (nr_segs > queue_max_segments(q))
+ return -EINVAL;
+
+ /* no iovecs to alloc, as we already have a BVEC iterator */
+ bio = bio_map_get(rq, 0, GFP_KERNEL);
+ if (bio == NULL)
+ return -ENOMEM;
+
+ bio_iov_bvec_set(bio, iter);
+ blk_rq_bio_prep(rq, bio, nr_segs);
+
+ /* loop to perform a bunch of sanity checks */
+ bvecs = (struct bio_vec *)iter->bvec;
+ for (i = 0; i < nr_segs; i++) {
+ bv = &bvecs[i];
+ /*
+ * If the queue doesn't support SG gaps and adding this
+ * offset would create a gap, disallow it.
+ */
+ if (bvprvp && bvec_gap_to_prev(lim, bvprvp, bv->bv_offset))
+ goto put_bio;
+
+ /* check full condition */
+ if (nsegs >= nr_segs || bytes > UINT_MAX - bv->bv_len)
+ goto put_bio;
+ if (bytes + bv->bv_len > nr_iter)
+ goto put_bio;
+ if (bv->bv_offset + bv->bv_len > PAGE_SIZE)
+ goto put_bio;
+
+ nsegs++;
+ bytes += bv->bv_len;
+ bvprvp = bv;
+ }
+ return 0;
+put_bio:
+ bio_map_put(bio);
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(blk_rq_map_user_bvec);
+
/**
* blk_rq_unmap_user - unmap a request with user data
* @bio: start of bio list
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 00a15808c137..1a9ae17e49be 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -977,6 +977,7 @@ struct rq_map_data {
bool from_user;
};
+int blk_rq_map_user_bvec(struct request *rq, struct iov_iter *iter);
int blk_rq_map_user(struct request_queue *, struct request *,
struct rq_map_data *, void __user *, unsigned long, gfp_t);
int blk_rq_map_user_iov(struct request_queue *, struct request *,
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH for-next v9 7/7] nvme: wire up fixed buffer support for nvme passthrough
[not found] ` <CGME20220925203340epcas5p21bd73962a73c36c7bd56841299c0d229@epcas5p2.samsung.com>
@ 2022-09-25 20:23 ` Kanchan Joshi
0 siblings, 0 replies; 9+ messages in thread
From: Kanchan Joshi @ 2022-09-25 20:23 UTC (permalink / raw)
To: axboe, hch, kbusch
Cc: io-uring, linux-nvme, linux-block, gost.dev, Kanchan Joshi
if io_uring sends passthrough command with IORING_URING_CMD_FIXED flag,
use the pre-registered buffer for IO (non-vectored variant). Pass the
buffer/length to io_uring and get the bvec iterator for the range. Next,
pass this bvec to block-layer helper and obtain a bio/request for
subsequent processing.
While at it, modify nvme_submit_user_cmd to take ubuffer as plain integer
argument, and do away with nvme_to_user_ptr conversion in callers.
Signed-off-by: Kanchan Joshi <[email protected]>
---
drivers/nvme/host/ioctl.c | 44 +++++++++++++++++++++++++--------------
1 file changed, 28 insertions(+), 16 deletions(-)
diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index b9f17dc87de9..505a548d4da5 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -83,9 +83,10 @@ static struct request *nvme_alloc_user_request(struct request_queue *q,
return req;
}
-static int nvme_map_user_request(struct request *req, void __user *ubuffer,
+static int nvme_map_user_request(struct request *req, u64 ubuffer,
unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
- u32 meta_seed, void **metap, bool vec)
+ u32 meta_seed, void **metap, struct io_uring_cmd *ioucmd,
+ bool vec)
{
struct request_queue *q = req->q;
struct nvme_ns *ns = q->queuedata;
@@ -93,23 +94,34 @@ static int nvme_map_user_request(struct request *req, void __user *ubuffer,
struct bio *bio = NULL;
void *meta = NULL;
int ret;
+ bool fixedbufs = ioucmd && (ioucmd->flags & IORING_URING_CMD_FIXED);
- if (!vec)
- ret = blk_rq_map_user(q, req, NULL, ubuffer, bufflen,
- GFP_KERNEL);
- else {
+ if (vec) {
struct iovec fast_iov[UIO_FASTIOV];
struct iovec *iov = fast_iov;
struct iov_iter iter;
- ret = import_iovec(rq_data_dir(req), ubuffer, bufflen,
- UIO_FASTIOV, &iov, &iter);
+ /* fixedbufs is only for non-vectored io */
+ WARN_ON_ONCE(fixedbufs);
+ ret = import_iovec(rq_data_dir(req), nvme_to_user_ptr(ubuffer),
+ bufflen, UIO_FASTIOV, &iov, &iter);
if (ret < 0)
goto out;
ret = blk_rq_map_user_iov(q, req, NULL, &iter, GFP_KERNEL);
kfree(iov);
- }
+ } else if (fixedbufs) {
+ struct iov_iter iter;
+
+ ret = io_uring_cmd_import_fixed(ubuffer, bufflen,
+ rq_data_dir(req), &iter, ioucmd);
+ if (ret < 0)
+ goto out;
+ ret = blk_rq_map_user_bvec(req, &iter);
+ } else
+ ret = blk_rq_map_user(q, req, NULL,
+ nvme_to_user_ptr(ubuffer), bufflen,
+ GFP_KERNEL);
if (ret)
goto out;
bio = req->bio;
@@ -136,7 +148,7 @@ static int nvme_map_user_request(struct request *req, void __user *ubuffer,
}
static int nvme_submit_user_cmd(struct request_queue *q,
- struct nvme_command *cmd, void __user *ubuffer,
+ struct nvme_command *cmd, u64 ubuffer,
unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
u32 meta_seed, u64 *result, unsigned timeout, bool vec)
{
@@ -152,7 +164,7 @@ static int nvme_submit_user_cmd(struct request_queue *q,
req->timeout = timeout;
if (ubuffer && bufflen) {
ret = nvme_map_user_request(req, ubuffer, bufflen, meta_buffer,
- meta_len, meta_seed, &meta, vec);
+ meta_len, meta_seed, &meta, NULL, vec);
if (ret)
goto out;
}
@@ -231,7 +243,7 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
c.rw.appmask = cpu_to_le16(io.appmask);
return nvme_submit_user_cmd(ns->queue, &c,
- nvme_to_user_ptr(io.addr), length,
+ io.addr, length,
metadata, meta_len, lower_32_bits(io.slba), NULL, 0,
false);
}
@@ -285,7 +297,7 @@ static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
timeout = msecs_to_jiffies(cmd.timeout_ms);
status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
- nvme_to_user_ptr(cmd.addr), cmd.data_len,
+ cmd.addr, cmd.data_len,
nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,
0, &result, timeout, false);
@@ -331,7 +343,7 @@ static int nvme_user_cmd64(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
timeout = msecs_to_jiffies(cmd.timeout_ms);
status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,
- nvme_to_user_ptr(cmd.addr), cmd.data_len,
+ cmd.addr, cmd.data_len,
nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,
0, &cmd.result, timeout, vec);
@@ -475,9 +487,9 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns,
req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0;
if (d.addr && d.data_len) {
- ret = nvme_map_user_request(req, nvme_to_user_ptr(d.addr),
+ ret = nvme_map_user_request(req, d.addr,
d.data_len, nvme_to_user_ptr(d.metadata),
- d.metadata_len, 0, &meta, vec);
+ d.metadata_len, 0, &meta, ioucmd, vec);
if (ret)
goto out_err;
}
--
2.25.1
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH for-next v9 6/7] block: introduce helper to map bvec iterator
2022-09-25 20:23 ` [PATCH for-next v9 6/7] block: introduce helper to map bvec iterator Kanchan Joshi
@ 2022-09-26 14:54 ` Christoph Hellwig
0 siblings, 0 replies; 9+ messages in thread
From: Christoph Hellwig @ 2022-09-26 14:54 UTC (permalink / raw)
To: Kanchan Joshi
Cc: axboe, hch, kbusch, io-uring, linux-nvme, linux-block, gost.dev,
Anuj Gupta
On Mon, Sep 26, 2022 at 01:53:03AM +0530, Kanchan Joshi wrote:
> Add blk_rq_map_user_bvec which maps the pages from bvec iterator into a
> bio, and places the bio into the request. This helper will be used by
> nvme for uring-passthrough path with pre-mapped buffers.
I still don't think this should be separate per the ongoing discussion.
It would also be nice if we had a chance to finish the discussion
without seeing a reposted series before we've made much progress on
it.
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2022-09-26 16:06 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <CGME20220925203314epcas5p2a075d1026db3a46df09a4b67108109b4@epcas5p2.samsung.com>
2022-09-25 20:22 ` [PATCH for-next v9 0/7] fixed-buffer for uring-cmd/passthru Kanchan Joshi
[not found] ` <CGME20220925203320epcas5p28fcc3c9ff8669c56213547725ea71001@epcas5p2.samsung.com>
2022-09-25 20:22 ` [PATCH for-next v9 1/7] io_uring: add io_uring_cmd_import_fixed Kanchan Joshi
[not found] ` <CGME20220925203325epcas5p1e4e89d414aa7a268a6e526d3c7c2261c@epcas5p1.samsung.com>
2022-09-25 20:22 ` [PATCH for-next v9 2/7] io_uring: introduce fixed buffer support for io_uring_cmd Kanchan Joshi
[not found] ` <CGME20220925203328epcas5p1872214ededaf3b75762dcb5af15199da@epcas5p1.samsung.com>
2022-09-25 20:23 ` [PATCH for-next v9 3/7] nvme: refactor nvme_add_user_metadata Kanchan Joshi
[not found] ` <CGME20220925203330epcas5p20c712fa919a4cc2a5ec3bbaa94bb72ca@epcas5p2.samsung.com>
2022-09-25 20:23 ` [PATCH for-next v9 4/7] nvme: refactor nvme_alloc_request Kanchan Joshi
[not found] ` <CGME20220925203332epcas5p3b080cce759996dec4e081f03e9ecd2f9@epcas5p3.samsung.com>
2022-09-25 20:23 ` [PATCH for-next v9 5/7] block: factor out bio_map_get helper Kanchan Joshi
[not found] ` <CGME20220925203336epcas5p39e910479f992d7d9e233210e0647a6bf@epcas5p3.samsung.com>
2022-09-25 20:23 ` [PATCH for-next v9 6/7] block: introduce helper to map bvec iterator Kanchan Joshi
2022-09-26 14:54 ` Christoph Hellwig
[not found] ` <CGME20220925203340epcas5p21bd73962a73c36c7bd56841299c0d229@epcas5p2.samsung.com>
2022-09-25 20:23 ` [PATCH for-next v9 7/7] nvme: wire up fixed buffer support for nvme passthrough Kanchan Joshi
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