Commit 89377bc1 authored by Kanchan Joshi's avatar Kanchan Joshi Committed by Christoph Hellwig
Browse files

nvme: add vectored-io support for user-passthrough 



Add a new NVME_IOCTL_IO64_CMD_VEC ioctl that works like the existing
NVME_IOCTL_IO64_CMD ioctl except that it takes and array of iovecs
and thus supports vectored I/O.

  - cmd.addr is base address of user iovec array
  - cmd.vec_cnt is count of iovec array elements

This patch does not include vectored-variant for admin-commands as most
of them are light on buffers and likely to have low invocation frequency.

Signed-off-by: default avatarKanchan Joshi <joshi.k@samsung.com>
Reviewed-by: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent bd83fe6f

drivers/nvme/host/ioctl.c

+26 −9
Original line number Diff line number Diff line
@@ -56,7 +56,7 @@ static void *nvme_add_user_metadata(struct bio *bio, void __user *ubuf, 
static int nvme_submit_user_cmd(struct request_queue *q,

		struct nvme_command *cmd, void __user *ubuffer,

		unsigned bufflen, void __user *meta_buffer, unsigned meta_len,

		u32 meta_seed, u64 *result, unsigned timeout)

		u32 meta_seed, u64 *result, unsigned timeout, bool vec)

{

	bool write = nvme_is_write(cmd);

	struct nvme_ns *ns = q->queuedata;
@@ -75,8 +75,22 @@ static int nvme_submit_user_cmd(struct request_queue *q, 
	nvme_req(req)->flags |= NVME_REQ_USERCMD;



	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)

			goto out;

		bio = req->bio;
@@ -170,7 +184,8 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio) 


	return nvme_submit_user_cmd(ns->queue, &c,

			nvme_to_user_ptr(io.addr), length,

			metadata, meta_len, lower_32_bits(io.slba), NULL, 0);

			metadata, meta_len, lower_32_bits(io.slba), NULL, 0,

			false);

}



static bool nvme_validate_passthru_nsid(struct nvme_ctrl *ctrl,
@@ -224,7 +239,7 @@ static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns, 
	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,

			nvme_to_user_ptr(cmd.addr), cmd.data_len,

			nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,

			0, &result, timeout);

			0, &result, timeout, false);



	if (status >= 0) {

		if (put_user(result, &ucmd->result))
@@ -235,7 +250,7 @@ static int nvme_user_cmd(struct nvme_ctrl *ctrl, struct nvme_ns *ns, 
}



static int nvme_user_cmd64(struct nvme_ctrl *ctrl, struct nvme_ns *ns,

			struct nvme_passthru_cmd64 __user *ucmd)

			struct nvme_passthru_cmd64 __user *ucmd, bool vec)

{

	struct nvme_passthru_cmd64 cmd;

	struct nvme_command c;
@@ -270,7 +285,7 @@ static int nvme_user_cmd64(struct nvme_ctrl *ctrl, struct nvme_ns *ns, 
	status = nvme_submit_user_cmd(ns ? ns->queue : ctrl->admin_q, &c,

			nvme_to_user_ptr(cmd.addr), cmd.data_len,

			nvme_to_user_ptr(cmd.metadata), cmd.metadata_len,

			0, &cmd.result, timeout);

			0, &cmd.result, timeout, vec);



	if (status >= 0) {

		if (put_user(cmd.result, &ucmd->result))
@@ -296,7 +311,7 @@ static int nvme_ctrl_ioctl(struct nvme_ctrl *ctrl, unsigned int cmd, 
	case NVME_IOCTL_ADMIN_CMD:

		return nvme_user_cmd(ctrl, NULL, argp);

	case NVME_IOCTL_ADMIN64_CMD:

		return nvme_user_cmd64(ctrl, NULL, argp);

		return nvme_user_cmd64(ctrl, NULL, argp, false);

	default:

		return sed_ioctl(ctrl->opal_dev, cmd, argp);

	}
@@ -340,7 +355,9 @@ static int nvme_ns_ioctl(struct nvme_ns *ns, unsigned int cmd, 
	case NVME_IOCTL_SUBMIT_IO:

		return nvme_submit_io(ns, argp);

	case NVME_IOCTL_IO64_CMD:

		return nvme_user_cmd64(ns->ctrl, ns, argp);

		return nvme_user_cmd64(ns->ctrl, ns, argp, false);

	case NVME_IOCTL_IO64_CMD_VEC:

		return nvme_user_cmd64(ns->ctrl, ns, argp, true);

	default:

		return -ENOTTY;

	}
@@ -480,7 +497,7 @@ long nvme_dev_ioctl(struct file *file, unsigned int cmd, 
	case NVME_IOCTL_ADMIN_CMD:

		return nvme_user_cmd(ctrl, NULL, argp);

	case NVME_IOCTL_ADMIN64_CMD:

		return nvme_user_cmd64(ctrl, NULL, argp);

		return nvme_user_cmd64(ctrl, NULL, argp, false);

	case NVME_IOCTL_IO_CMD:

		return nvme_dev_user_cmd(ctrl, argp);

	case NVME_IOCTL_RESET:

include/uapi/linux/nvme_ioctl.h

+5 −1
Original line number Diff line number Diff line
@@ -55,7 +55,10 @@ struct nvme_passthru_cmd64 { 
	__u64	metadata;

	__u64	addr;

	__u32	metadata_len;

	__u32	data_len;

	union {

		__u32	data_len; /* for non-vectored io */

		__u32	vec_cnt; /* for vectored io */

	};

	__u32	cdw10;

	__u32	cdw11;

	__u32	cdw12;
@@ -78,5 +81,6 @@ struct nvme_passthru_cmd64 { 
#define NVME_IOCTL_RESCAN	_IO('N', 0x46)

#define NVME_IOCTL_ADMIN64_CMD	_IOWR('N', 0x47, struct nvme_passthru_cmd64)

#define NVME_IOCTL_IO64_CMD	_IOWR('N', 0x48, struct nvme_passthru_cmd64)

#define NVME_IOCTL_IO64_CMD_VEC	_IOWR('N', 0x49, struct nvme_passthru_cmd64)



#endif /* _UAPI_LINUX_NVME_IOCTL_H */