Commit d1aa0346 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring/mock: add sync read/write 



Add support for synchronous zero read/write for mock files.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/571f3c9fe688e918256a06a722d3db6ced9ca3d5.1750599274.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4aac001f

include/uapi/linux/io_uring/mock_file.h

+3 −1
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ 


enum {

	IORING_MOCK_FEAT_CMD_COPY,

	IORING_MOCK_FEAT_RW_ZERO,



	IORING_MOCK_FEAT_END,

};
@@ -17,7 +18,8 @@ struct io_uring_mock_probe { 
struct io_uring_mock_create {

	__u32		out_fd;

	__u32		flags;

	__u64		__resv[15];

	__u64		file_size;

	__u64		__resv[14];

};



enum {

io_uring/mock_file.c

+62 −5
Original line number Diff line number Diff line
@@ -9,6 +9,10 @@ 
#include <linux/io_uring_types.h>

#include <uapi/linux/io_uring/mock_file.h>



struct io_mock_file {

	size_t size;

};



#define IO_VALID_COPY_CMD_FLAGS		IORING_MOCK_COPY_FROM



static int io_copy_regbuf(struct iov_iter *reg_iter, void __user *ubuf)
@@ -82,18 +86,59 @@ static int io_mock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) 
	return -ENOTSUPP;

}



static ssize_t io_mock_read_iter(struct kiocb *iocb, struct iov_iter *to)

{

	struct io_mock_file *mf = iocb->ki_filp->private_data;

	size_t len = iov_iter_count(to);



	if (iocb->ki_pos + len > mf->size)

		return -EINVAL;

	return iov_iter_zero(len, to);

}



static ssize_t io_mock_write_iter(struct kiocb *iocb, struct iov_iter *from)

{

	struct io_mock_file *mf = iocb->ki_filp->private_data;

	size_t len = iov_iter_count(from);



	if (iocb->ki_pos + len > mf->size)

		return -EINVAL;

	iov_iter_advance(from, len);

	return len;

}



static loff_t io_mock_llseek(struct file *file, loff_t offset, int whence)

{

	struct io_mock_file *mf = file->private_data;



	return fixed_size_llseek(file, offset, whence, mf->size);

}



static int io_mock_release(struct inode *inode, struct file *file)

{

	struct io_mock_file *mf = file->private_data;



	kfree(mf);

	return 0;

}



static const struct file_operations io_mock_fops = {

	.owner		= THIS_MODULE,

	.release	= io_mock_release,

	.uring_cmd	= io_mock_cmd,

	.read_iter	= io_mock_read_iter,

	.write_iter	= io_mock_write_iter,

	.llseek		= io_mock_llseek,

};



static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flags)

{

	const struct io_uring_sqe *sqe = cmd->sqe;

	struct io_uring_mock_create mc, __user *uarg;

	struct io_mock_file *mf = NULL;

	struct file *file = NULL;

	size_t uarg_size;

	int fd, ret;

	int fd = -1, ret;



	/*

	 * It's a testing only driver that allows exercising edge cases
@@ -114,18 +159,28 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag 
		return -EFAULT;

	if (!mem_is_zero(mc.__resv, sizeof(mc.__resv)) || mc.flags)

		return -EINVAL;

	if (mc.file_size > SZ_1G)

		return -EINVAL;

	mf = kzalloc(sizeof(*mf), GFP_KERNEL_ACCOUNT);

	if (!mf)

		return -ENOMEM;



	fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);

	ret = fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);

	if (fd < 0)

		return fd;

		goto fail;



	mf->size = mc.file_size;

	file = anon_inode_create_getfile("[io_uring_mock]", &io_mock_fops,

					 NULL, O_RDWR | O_CLOEXEC, NULL);

					 mf, O_RDWR | O_CLOEXEC, NULL);

	if (IS_ERR(file)) {

		ret = PTR_ERR(file);

		goto fail;

	}



	file->f_mode |= FMODE_READ | FMODE_CAN_READ |

			FMODE_WRITE | FMODE_CAN_WRITE |

			FMODE_LSEEK;



	mc.out_fd = fd;

	if (copy_to_user(uarg, &mc, uarg_size)) {

		fput(file);
@@ -136,7 +191,9 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag 
	fd_install(fd, file);

	return 0;

fail:

	if (fd >= 0)

		put_unused_fd(fd);

	kfree(mf);

	return ret;

}