* [PATCH v5 1/6] io_uring/mock: add basic infra for test mock files
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 2/6] io_uring/mock: add cmd using vectored regbufs Pavel Begunkov
` (5 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
io_uring commands provide an ioctl style interface for files to
implement file specific operations. io_uring provides many features and
advanced api to commands, and it's getting hard to test as it requires
specific files/devices.
Add basic infrastucture for creating special mock files that will be
implementing the cmd api and using various io_uring features we want to
test. It'll also be useful to test some more obscure read/write/polling
edge cases in the future.
Suggested-by: chase xd <sl1589472800@gmail.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
MAINTAINERS | 1 +
include/uapi/linux/io_uring/mock_file.h | 22 ++++
init/Kconfig | 11 ++
io_uring/Makefile | 1 +
io_uring/mock_file.c | 148 ++++++++++++++++++++++++
5 files changed, 183 insertions(+)
create mode 100644 include/uapi/linux/io_uring/mock_file.h
create mode 100644 io_uring/mock_file.c
diff --git a/MAINTAINERS b/MAINTAINERS
index a92290fffa16..088348e3b3ae 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12679,6 +12679,7 @@ F: include/linux/io_uring.h
F: include/linux/io_uring_types.h
F: include/trace/events/io_uring.h
F: include/uapi/linux/io_uring.h
+F: include/uapi/linux/io_uring/
F: io_uring/
IPMI SUBSYSTEM
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
new file mode 100644
index 000000000000..a44273fd526d
--- /dev/null
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -0,0 +1,22 @@
+#ifndef LINUX_IO_URING_MOCK_FILE_H
+#define LINUX_IO_URING_MOCK_FILE_H
+
+#include <linux/types.h>
+
+struct io_uring_mock_probe {
+ __u64 features;
+ __u64 __resv[9];
+};
+
+struct io_uring_mock_create {
+ __u32 out_fd;
+ __u32 flags;
+ __u64 __resv[15];
+};
+
+enum {
+ IORING_MOCK_MGR_CMD_PROBE,
+ IORING_MOCK_MGR_CMD_CREATE,
+};
+
+#endif
diff --git a/init/Kconfig b/init/Kconfig
index af4c2f085455..c40a7c65fb4c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1801,6 +1801,17 @@ config GCOV_PROFILE_URING
the io_uring subsystem, hence this should only be enabled for
specific test purposes.
+config IO_URING_MOCK_FILE
+ tristate "Enable io_uring mock files (Experimental)" if EXPERT
+ default n
+ depends on IO_URING
+ help
+ Enable mock files for io_uring subststem testing. The ABI might
+ still change, so it's still experimental and should only be enabled
+ for specific test purposes.
+
+ If unsure, say N.
+
config ADVISE_SYSCALLS
bool "Enable madvise/fadvise syscalls" if EXPERT
default y
diff --git a/io_uring/Makefile b/io_uring/Makefile
index d97c6b51d584..b3f1bd492804 100644
--- a/io_uring/Makefile
+++ b/io_uring/Makefile
@@ -21,3 +21,4 @@ obj-$(CONFIG_EPOLL) += epoll.o
obj-$(CONFIG_NET_RX_BUSY_POLL) += napi.o
obj-$(CONFIG_NET) += net.o cmd_net.o
obj-$(CONFIG_PROC_FS) += fdinfo.o
+obj-$(CONFIG_IO_URING_MOCK_FILE) += mock_file.o
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
new file mode 100644
index 000000000000..3681d0b8d8de
--- /dev/null
+++ b/io_uring/mock_file.c
@@ -0,0 +1,148 @@
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/anon_inodes.h>
+
+#include <linux/io_uring/cmd.h>
+#include <linux/io_uring_types.h>
+#include <uapi/linux/io_uring/mock_file.h>
+
+static int io_mock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
+{
+ return -ENOTSUPP;
+}
+
+static const struct file_operations io_mock_fops = {
+ .owner = THIS_MODULE,
+ .uring_cmd = io_mock_cmd,
+};
+
+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 file *file = NULL;
+ size_t uarg_size;
+ int fd, ret;
+
+ /*
+ * It's a testing only driver that allows exercising edge cases
+ * that wouldn't be possible to hit otherwise.
+ */
+ add_taint(TAINT_TEST, LOCKDEP_STILL_OK);
+
+ uarg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ uarg_size = READ_ONCE(sqe->len);
+
+ if (sqe->ioprio || sqe->__pad1 || sqe->addr3 || sqe->file_index)
+ return -EINVAL;
+ if (uarg_size != sizeof(mc))
+ return -EINVAL;
+
+ memset(&mc, 0, sizeof(mc));
+ if (copy_from_user(&mc, uarg, uarg_size))
+ return -EFAULT;
+ if (!mem_is_zero(mc.__resv, sizeof(mc.__resv)) || mc.flags)
+ return -EINVAL;
+
+ fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
+ if (fd < 0)
+ return fd;
+
+ file = anon_inode_create_getfile("[io_uring_mock]", &io_mock_fops,
+ NULL, O_RDWR | O_CLOEXEC, NULL);
+ if (IS_ERR(file)) {
+ ret = PTR_ERR(file);
+ goto fail;
+ }
+
+ mc.out_fd = fd;
+ if (copy_to_user(uarg, &mc, uarg_size)) {
+ fput(file);
+ ret = -EFAULT;
+ goto fail;
+ }
+
+ fd_install(fd, file);
+ return 0;
+fail:
+ put_unused_fd(fd);
+ return ret;
+}
+
+static int io_probe_mock(struct io_uring_cmd *cmd)
+{
+ const struct io_uring_sqe *sqe = cmd->sqe;
+ struct io_uring_mock_probe mp, __user *uarg;
+ size_t uarg_size;
+
+ uarg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ uarg_size = READ_ONCE(sqe->len);
+
+ if (sqe->ioprio || sqe->__pad1 || sqe->addr3 || sqe->file_index ||
+ uarg_size != sizeof(mp))
+ return -EINVAL;
+
+ memset(&mp, 0, sizeof(mp));
+ if (copy_from_user(&mp, uarg, uarg_size))
+ return -EFAULT;
+ if (!mem_is_zero(&mp, sizeof(mp)))
+ return -EINVAL;
+
+ mp.features = 0;
+
+ if (copy_to_user(uarg, &mp, uarg_size))
+ return -EFAULT;
+ return 0;
+}
+
+static int iou_mock_mgr_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
+{
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ switch (cmd->cmd_op) {
+ case IORING_MOCK_MGR_CMD_PROBE:
+ return io_probe_mock(cmd);
+ case IORING_MOCK_MGR_CMD_CREATE:
+ return io_create_mock_file(cmd, issue_flags);
+ }
+ return -EOPNOTSUPP;
+}
+
+static const struct file_operations iou_mock_dev_fops = {
+ .owner = THIS_MODULE,
+ .uring_cmd = iou_mock_mgr_cmd,
+};
+
+static struct miscdevice iou_mock_miscdev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "io_uring_mock",
+ .fops = &iou_mock_dev_fops,
+};
+
+static int __init io_mock_init(void)
+{
+ int ret;
+
+ ret = misc_register(&iou_mock_miscdev);
+ if (ret < 0) {
+ pr_err("Could not initialize io_uring mock device\n");
+ return ret;
+ }
+ return 0;
+}
+
+static void __exit io_mock_exit(void)
+{
+ misc_deregister(&iou_mock_miscdev);
+}
+
+module_init(io_mock_init)
+module_exit(io_mock_exit)
+
+MODULE_AUTHOR("Pavel Begunkov <asml.silence@gmail.com>");
+MODULE_DESCRIPTION("io_uring mock file");
+MODULE_LICENSE("GPL");
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v5 2/6] io_uring/mock: add cmd using vectored regbufs
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 1/6] " Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 3/6] io_uring/mock: add sync read/write Pavel Begunkov
` (4 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
There is a command api allowing to import vectored registered buffers,
add a new mock command that uses the feature and simply copies the
specified registered buffer into user space or vice versa.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring/mock_file.h | 14 +++++
io_uring/mock_file.c | 70 ++++++++++++++++++++++++-
2 files changed, 83 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
index a44273fd526d..73aca477d5c8 100644
--- a/include/uapi/linux/io_uring/mock_file.h
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -3,6 +3,12 @@
#include <linux/types.h>
+enum {
+ IORING_MOCK_FEAT_CMD_COPY,
+
+ IORING_MOCK_FEAT_END,
+};
+
struct io_uring_mock_probe {
__u64 features;
__u64 __resv[9];
@@ -19,4 +25,12 @@ enum {
IORING_MOCK_MGR_CMD_CREATE,
};
+enum {
+ IORING_MOCK_CMD_COPY_REGBUF,
+};
+
+enum {
+ IORING_MOCK_COPY_FROM = 1,
+};
+
#endif
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
index 3681d0b8d8de..8285393f4a5b 100644
--- a/io_uring/mock_file.c
+++ b/io_uring/mock_file.c
@@ -9,8 +9,76 @@
#include <linux/io_uring_types.h>
#include <uapi/linux/io_uring/mock_file.h>
+#define IO_VALID_COPY_CMD_FLAGS IORING_MOCK_COPY_FROM
+
+static int io_copy_regbuf(struct iov_iter *reg_iter, void __user *ubuf)
+{
+ size_t ret, copied = 0;
+ size_t buflen = PAGE_SIZE;
+ void *tmp_buf;
+
+ tmp_buf = kzalloc(buflen, GFP_KERNEL);
+ if (!tmp_buf)
+ return -ENOMEM;
+
+ while (iov_iter_count(reg_iter)) {
+ size_t len = min(iov_iter_count(reg_iter), buflen);
+
+ if (iov_iter_rw(reg_iter) == ITER_SOURCE) {
+ ret = copy_from_iter(tmp_buf, len, reg_iter);
+ if (ret <= 0)
+ break;
+ if (copy_to_user(ubuf, tmp_buf, ret))
+ break;
+ } else {
+ if (copy_from_user(tmp_buf, ubuf, len))
+ break;
+ ret = copy_to_iter(tmp_buf, len, reg_iter);
+ if (ret <= 0)
+ break;
+ }
+ ubuf += ret;
+ copied += ret;
+ }
+
+ kfree(tmp_buf);
+ return copied;
+}
+
+static int io_cmd_copy_regbuf(struct io_uring_cmd *cmd, unsigned int issue_flags)
+{
+ const struct io_uring_sqe *sqe = cmd->sqe;
+ const struct iovec __user *iovec;
+ unsigned flags, iovec_len;
+ struct iov_iter iter;
+ void __user *ubuf;
+ int dir, ret;
+
+ ubuf = u64_to_user_ptr(READ_ONCE(sqe->addr3));
+ iovec = u64_to_user_ptr(READ_ONCE(sqe->addr));
+ iovec_len = READ_ONCE(sqe->len);
+ flags = READ_ONCE(sqe->file_index);
+
+ if (unlikely(sqe->ioprio || sqe->__pad1))
+ return -EINVAL;
+ if (flags & ~IO_VALID_COPY_CMD_FLAGS)
+ return -EINVAL;
+
+ dir = (flags & IORING_MOCK_COPY_FROM) ? ITER_SOURCE : ITER_DEST;
+ ret = io_uring_cmd_import_fixed_vec(cmd, iovec, iovec_len, dir, &iter,
+ issue_flags);
+ if (ret)
+ return ret;
+ ret = io_copy_regbuf(&iter, ubuf);
+ return ret ? ret : -EFAULT;
+}
+
static int io_mock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
{
+ switch (cmd->cmd_op) {
+ case IORING_MOCK_CMD_COPY_REGBUF:
+ return io_cmd_copy_regbuf(cmd, issue_flags);
+ }
return -ENOTSUPP;
}
@@ -91,7 +159,7 @@ static int io_probe_mock(struct io_uring_cmd *cmd)
if (!mem_is_zero(&mp, sizeof(mp)))
return -EINVAL;
- mp.features = 0;
+ mp.features = IORING_MOCK_FEAT_END;
if (copy_to_user(uarg, &mp, uarg_size))
return -EFAULT;
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v5 3/6] io_uring/mock: add sync read/write
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 1/6] " Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 2/6] io_uring/mock: add cmd using vectored regbufs Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 4/6] io_uring/mock: allow to choose FMODE_NOWAIT Pavel Begunkov
` (3 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
Add support for synchronous zero read/write for mock files.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring/mock_file.h | 4 +-
io_uring/mock_file.c | 67 +++++++++++++++++++++++--
2 files changed, 65 insertions(+), 6 deletions(-)
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
index 73aca477d5c8..de27295bb365 100644
--- a/include/uapi/linux/io_uring/mock_file.h
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -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 {
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
index 8285393f4a5b..90160ccb50f0 100644
--- a/io_uring/mock_file.c
+++ b/io_uring/mock_file.c
@@ -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:
- put_unused_fd(fd);
+ if (fd >= 0)
+ put_unused_fd(fd);
+ kfree(mf);
return ret;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v5 4/6] io_uring/mock: allow to choose FMODE_NOWAIT
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
` (2 preceding siblings ...)
2025-06-30 18:16 ` [PATCH v5 3/6] io_uring/mock: add sync read/write Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 5/6] io_uring/mock: support for async read/write Pavel Begunkov
` (2 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
Add an option to choose whether the file supports FMODE_NOWAIT, that
changes the execution path io_uring request takes.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring/mock_file.h | 5 +++++
io_uring/mock_file.c | 8 +++++++-
2 files changed, 12 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
index de27295bb365..125949d2b5ce 100644
--- a/include/uapi/linux/io_uring/mock_file.h
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -6,6 +6,7 @@
enum {
IORING_MOCK_FEAT_CMD_COPY,
IORING_MOCK_FEAT_RW_ZERO,
+ IORING_MOCK_FEAT_RW_NOWAIT,
IORING_MOCK_FEAT_END,
};
@@ -15,6 +16,10 @@ struct io_uring_mock_probe {
__u64 __resv[9];
};
+enum {
+ IORING_MOCK_CREATE_F_SUPPORT_NOWAIT = 1,
+};
+
struct io_uring_mock_create {
__u32 out_fd;
__u32 flags;
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
index 90160ccb50f0..0eb1d3bd6368 100644
--- a/io_uring/mock_file.c
+++ b/io_uring/mock_file.c
@@ -131,6 +131,8 @@ static const struct file_operations io_mock_fops = {
.llseek = io_mock_llseek,
};
+#define IO_VALID_CREATE_FLAGS (IORING_MOCK_CREATE_F_SUPPORT_NOWAIT)
+
static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flags)
{
const struct io_uring_sqe *sqe = cmd->sqe;
@@ -157,7 +159,9 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag
memset(&mc, 0, sizeof(mc));
if (copy_from_user(&mc, uarg, uarg_size))
return -EFAULT;
- if (!mem_is_zero(mc.__resv, sizeof(mc.__resv)) || mc.flags)
+ if (!mem_is_zero(mc.__resv, sizeof(mc.__resv)))
+ return -EINVAL;
+ if (mc.flags & ~IO_VALID_CREATE_FLAGS)
return -EINVAL;
if (mc.file_size > SZ_1G)
return -EINVAL;
@@ -180,6 +184,8 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag
file->f_mode |= FMODE_READ | FMODE_CAN_READ |
FMODE_WRITE | FMODE_CAN_WRITE |
FMODE_LSEEK;
+ if (mc.flags & IORING_MOCK_CREATE_F_SUPPORT_NOWAIT)
+ file->f_mode |= FMODE_NOWAIT;
mc.out_fd = fd;
if (copy_to_user(uarg, &mc, uarg_size)) {
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v5 5/6] io_uring/mock: support for async read/write
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
` (3 preceding siblings ...)
2025-06-30 18:16 ` [PATCH v5 4/6] io_uring/mock: allow to choose FMODE_NOWAIT Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-06-30 18:16 ` [PATCH v5 6/6] io_uring/mock: add trivial poll handler Pavel Begunkov
2025-07-02 14:17 ` [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Jens Axboe
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
Let the user to specify a delay to read/write request. io_uring will
start a timer, return -EIOCBQUEUED and complete the request
asynchronously after the delay pass.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring/mock_file.h | 4 +-
io_uring/mock_file.c | 59 +++++++++++++++++++++++--
2 files changed, 58 insertions(+), 5 deletions(-)
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
index 125949d2b5ce..c8fa77e39c68 100644
--- a/include/uapi/linux/io_uring/mock_file.h
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -7,6 +7,7 @@ enum {
IORING_MOCK_FEAT_CMD_COPY,
IORING_MOCK_FEAT_RW_ZERO,
IORING_MOCK_FEAT_RW_NOWAIT,
+ IORING_MOCK_FEAT_RW_ASYNC,
IORING_MOCK_FEAT_END,
};
@@ -24,7 +25,8 @@ struct io_uring_mock_create {
__u32 out_fd;
__u32 flags;
__u64 file_size;
- __u64 __resv[14];
+ __u64 rw_delay_ns;
+ __u64 __resv[13];
};
enum {
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
index 0eb1d3bd6368..ed6a5505763e 100644
--- a/io_uring/mock_file.c
+++ b/io_uring/mock_file.c
@@ -4,13 +4,22 @@
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/anon_inodes.h>
+#include <linux/ktime.h>
+#include <linux/hrtimer.h>
#include <linux/io_uring/cmd.h>
#include <linux/io_uring_types.h>
#include <uapi/linux/io_uring/mock_file.h>
+struct io_mock_iocb {
+ struct kiocb *iocb;
+ struct hrtimer timer;
+ int res;
+};
+
struct io_mock_file {
- size_t size;
+ size_t size;
+ u64 rw_delay_ns;
};
#define IO_VALID_COPY_CMD_FLAGS IORING_MOCK_COPY_FROM
@@ -86,14 +95,48 @@ static int io_mock_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
return -ENOTSUPP;
}
+static enum hrtimer_restart io_mock_rw_timer_expired(struct hrtimer *timer)
+{
+ struct io_mock_iocb *mio = container_of(timer, struct io_mock_iocb, timer);
+ struct kiocb *iocb = mio->iocb;
+
+ WRITE_ONCE(iocb->private, NULL);
+ iocb->ki_complete(iocb, mio->res);
+ kfree(mio);
+ return HRTIMER_NORESTART;
+}
+
+static ssize_t io_mock_delay_rw(struct kiocb *iocb, size_t len)
+{
+ struct io_mock_file *mf = iocb->ki_filp->private_data;
+ struct io_mock_iocb *mio;
+
+ mio = kzalloc(sizeof(*mio), GFP_KERNEL);
+ if (!mio)
+ return -ENOMEM;
+
+ mio->iocb = iocb;
+ mio->res = len;
+ hrtimer_setup(&mio->timer, io_mock_rw_timer_expired,
+ CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer_start(&mio->timer, ns_to_ktime(mf->rw_delay_ns),
+ HRTIMER_MODE_REL);
+ return -EIOCBQUEUED;
+}
+
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);
+ size_t nr_zeroed;
if (iocb->ki_pos + len > mf->size)
return -EINVAL;
- return iov_iter_zero(len, to);
+ nr_zeroed = iov_iter_zero(len, to);
+ if (!mf->rw_delay_ns || nr_zeroed != len)
+ return nr_zeroed;
+
+ return io_mock_delay_rw(iocb, len);
}
static ssize_t io_mock_write_iter(struct kiocb *iocb, struct iov_iter *from)
@@ -103,8 +146,12 @@ static ssize_t io_mock_write_iter(struct kiocb *iocb, struct iov_iter *from)
if (iocb->ki_pos + len > mf->size)
return -EINVAL;
- iov_iter_advance(from, len);
- return len;
+ if (!mf->rw_delay_ns) {
+ iov_iter_advance(from, len);
+ return len;
+ }
+
+ return io_mock_delay_rw(iocb, len);
}
static loff_t io_mock_llseek(struct file *file, loff_t offset, int whence)
@@ -165,6 +212,9 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag
return -EINVAL;
if (mc.file_size > SZ_1G)
return -EINVAL;
+ if (mc.rw_delay_ns > NSEC_PER_SEC)
+ return -EINVAL;
+
mf = kzalloc(sizeof(*mf), GFP_KERNEL_ACCOUNT);
if (!mf)
return -ENOMEM;
@@ -174,6 +224,7 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag
goto fail;
mf->size = mc.file_size;
+ mf->rw_delay_ns = mc.rw_delay_ns;
file = anon_inode_create_getfile("[io_uring_mock]", &io_mock_fops,
mf, O_RDWR | O_CLOEXEC, NULL);
if (IS_ERR(file)) {
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* [PATCH v5 6/6] io_uring/mock: add trivial poll handler
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
` (4 preceding siblings ...)
2025-06-30 18:16 ` [PATCH v5 5/6] io_uring/mock: support for async read/write Pavel Begunkov
@ 2025-06-30 18:16 ` Pavel Begunkov
2025-07-02 14:17 ` [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Jens Axboe
6 siblings, 0 replies; 8+ messages in thread
From: Pavel Begunkov @ 2025-06-30 18:16 UTC (permalink / raw)
To: io-uring; +Cc: asml.silence
Add a flag that enables polling on the mock file. For now it's trivially
says that there is always data available, it'll be extended in the
future.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
include/uapi/linux/io_uring/mock_file.h | 2 ++
io_uring/mock_file.c | 37 +++++++++++++++++++++++--
2 files changed, 37 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/io_uring/mock_file.h b/include/uapi/linux/io_uring/mock_file.h
index c8fa77e39c68..debeee8e4527 100644
--- a/include/uapi/linux/io_uring/mock_file.h
+++ b/include/uapi/linux/io_uring/mock_file.h
@@ -8,6 +8,7 @@ enum {
IORING_MOCK_FEAT_RW_ZERO,
IORING_MOCK_FEAT_RW_NOWAIT,
IORING_MOCK_FEAT_RW_ASYNC,
+ IORING_MOCK_FEAT_POLL,
IORING_MOCK_FEAT_END,
};
@@ -19,6 +20,7 @@ struct io_uring_mock_probe {
enum {
IORING_MOCK_CREATE_F_SUPPORT_NOWAIT = 1,
+ IORING_MOCK_CREATE_F_POLL = 2,
};
struct io_uring_mock_create {
diff --git a/io_uring/mock_file.c b/io_uring/mock_file.c
index ed6a5505763e..45d3735b2708 100644
--- a/io_uring/mock_file.c
+++ b/io_uring/mock_file.c
@@ -6,6 +6,7 @@
#include <linux/anon_inodes.h>
#include <linux/ktime.h>
#include <linux/hrtimer.h>
+#include <linux/poll.h>
#include <linux/io_uring/cmd.h>
#include <linux/io_uring_types.h>
@@ -20,6 +21,8 @@ struct io_mock_iocb {
struct io_mock_file {
size_t size;
u64 rw_delay_ns;
+ bool pollable;
+ struct wait_queue_head poll_wq;
};
#define IO_VALID_COPY_CMD_FLAGS IORING_MOCK_COPY_FROM
@@ -161,6 +164,18 @@ static loff_t io_mock_llseek(struct file *file, loff_t offset, int whence)
return fixed_size_llseek(file, offset, whence, mf->size);
}
+static __poll_t io_mock_poll(struct file *file, struct poll_table_struct *pt)
+{
+ struct io_mock_file *mf = file->private_data;
+ __poll_t mask = 0;
+
+ poll_wait(file, &mf->poll_wq, pt);
+
+ mask |= EPOLLOUT | EPOLLWRNORM;
+ mask |= EPOLLIN | EPOLLRDNORM;
+ return mask;
+}
+
static int io_mock_release(struct inode *inode, struct file *file)
{
struct io_mock_file *mf = file->private_data;
@@ -178,10 +193,22 @@ static const struct file_operations io_mock_fops = {
.llseek = io_mock_llseek,
};
-#define IO_VALID_CREATE_FLAGS (IORING_MOCK_CREATE_F_SUPPORT_NOWAIT)
+static const struct file_operations io_mock_poll_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,
+ .poll = io_mock_poll,
+};
+
+#define IO_VALID_CREATE_FLAGS (IORING_MOCK_CREATE_F_SUPPORT_NOWAIT | \
+ IORING_MOCK_CREATE_F_POLL)
static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flags)
{
+ const struct file_operations *fops = &io_mock_fops;
const struct io_uring_sqe *sqe = cmd->sqe;
struct io_uring_mock_create mc, __user *uarg;
struct io_mock_file *mf = NULL;
@@ -223,9 +250,15 @@ static int io_create_mock_file(struct io_uring_cmd *cmd, unsigned int issue_flag
if (fd < 0)
goto fail;
+ init_waitqueue_head(&mf->poll_wq);
mf->size = mc.file_size;
mf->rw_delay_ns = mc.rw_delay_ns;
- file = anon_inode_create_getfile("[io_uring_mock]", &io_mock_fops,
+ if (mc.flags & IORING_MOCK_CREATE_F_POLL) {
+ fops = &io_mock_poll_fops;
+ mf->pollable = true;
+ }
+
+ file = anon_inode_create_getfile("[io_uring_mock]", fops,
mf, O_RDWR | O_CLOEXEC, NULL);
if (IS_ERR(file)) {
ret = PTR_ERR(file);
--
2.49.0
^ permalink raw reply related [flat|nested] 8+ messages in thread* Re: [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files
2025-06-30 18:16 [PATCH v5 0/6] io_uring/mock: add basic infra for test mock files Pavel Begunkov
` (5 preceding siblings ...)
2025-06-30 18:16 ` [PATCH v5 6/6] io_uring/mock: add trivial poll handler Pavel Begunkov
@ 2025-07-02 14:17 ` Jens Axboe
6 siblings, 0 replies; 8+ messages in thread
From: Jens Axboe @ 2025-07-02 14:17 UTC (permalink / raw)
To: io-uring, Pavel Begunkov
On Mon, 30 Jun 2025 19:16:50 +0100, Pavel Begunkov wrote:
> io_uring commands provide an ioctl style interface for files to
> implement file specific operations. io_uring provides many features and
> advanced api to commands, and it's getting hard to test as it requires
> specific files/devices.
>
> Add basic infrastucture for creating special mock files that will be
> implementing the cmd api and using various io_uring features we want to
> test. It'll also be useful to test some more obscure read/write/polling
> edge cases in the future, which was initially suggested by Chase.
>
> [...]
Applied, thanks!
[1/6] io_uring/mock: add basic infra for test mock files
(no commit info)
[2/6] io_uring/mock: add cmd using vectored regbufs
(no commit info)
[3/6] io_uring/mock: add sync read/write
(no commit info)
[4/6] io_uring/mock: allow to choose FMODE_NOWAIT
(no commit info)
[5/6] io_uring/mock: support for async read/write
(no commit info)
[6/6] io_uring/mock: add trivial poll handler
(no commit info)
Best regards,
--
Jens Axboe
^ permalink raw reply [flat|nested] 8+ messages in thread