[linux-morello-ltp] Re: [PATCH 1/2] syscalls/io_uring: Update uAPI structs

On 04-04-2023 10:18, Kevin Brodsky wrote:

On 16/03/2023 15:23, Tudor Cretu wrote:

...

Update the signatures for the uAPI io_uring structs bringing in support for capabilities and re-visit relevant testcases to take into account the structs' new published versions.

Signed-off-by: Tudor Cretu tudor.cretu@arm.com

include/lapi/io_uring.h | 10 +++++----- testcases/kernel/syscalls/io_uring/io_uring01.c | 4 ++-- testcases/kernel/syscalls/io_uring/io_uring02.c | 6 +++--- 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/lapi/io_uring.h b/include/lapi/io_uring.h index a63741a08..102e7945f 100644 --- a/include/lapi/io_uring.h +++ b/include/lapi/io_uring.h @@ -38,9 +38,9 @@ struct io_uring_sqe { int32_t fd; /* file descriptor to do IO on */ union { uint64_t off; /* offset into file */

• uint64_t	addr2;
  

• uintptr_t	addr2;
  

This will break the struct layout in 32-bit. If we cannot use the uapi header directly, then we probably need to define something akin to __kernel_uintptr_t here.

Ah, good point!

...

};

• uint64_t addr; /* pointer to buffer or iovecs */

• uintptr_t addr; /* pointer to buffer or iovecs */ uint32_t len; /* buffer size or number of iovecs */ union { __kernel_rwf_t rw_flags;

@@ -55,7 +55,7 @@ struct io_uring_sqe { uint32_t statx_flags; uint32_t fadvise_advice; };

• uint64_t user_data; /* data to be passed back at completion time */

• uintptr_t user_data; /* data to be passed back at completion time */ union { struct { /* index into fixed buffers, if used */

AFAICT __pad2 also needs to be expanded. In fact I'm surprised that these changes work in PCuABI as they stand, because with __pad2 unchanged I would expect the struct to be 16 bytes smaller than the uapi definition. Maybe I'm missing something?

Good catch!

This struct is not actually used. The uAPI header is used if it exists, here (lines 21-25):

https://git.morello-project.org/tudcre01/morello-linux-ltp/-/blob/81111e0f44...

Kevin

...

@@ -143,7 +143,7 @@ enum {

• IO completion data structure (Completion Queue Entry)

*/ struct io_uring_cqe {

• uint64_t user_data; /* sqe->data submission passed back */

• uintptr_t user_data; /* sqe->data submission passed back */ int32_t res; /* result code for this event */ uint32_t flags; };

@@ -234,7 +234,7 @@ struct io_uring_params { struct io_uring_files_update { uint32_t offset; uint32_t resv;

• uint64_t __attribute__((aligned(8))) fds;

• uintptr_t __attribute__((aligned(8))) fds; };

#define IO_URING_OP_SUPPORTED (1U << 0) diff --git a/testcases/kernel/syscalls/io_uring/io_uring01.c b/testcases/kernel/syscalls/io_uring/io_uring01.c index 70151bb85..744c7eca2 100644 --- a/testcases/kernel/syscalls/io_uring/io_uring01.c +++ b/testcases/kernel/syscalls/io_uring/io_uring01.c @@ -203,10 +203,10 @@ static int submit_to_uring_sq(struct submitter *s, struct tcase *tc) sqe->flags = 0; sqe->fd = fd; sqe->opcode = tc->enter_flags;

• sqe->addr = (unsigned long)iov->iov_base;

• sqe->addr = (uintptr_t)iov->iov_base; sqe->len = BLOCK_SZ; sqe->off = 0;

• sqe->user_data = (unsigned long long)iov;

• sqe->user_data = (uintptr_t)iov; sring->array[index] = index; tail = next_tail;

diff --git a/testcases/kernel/syscalls/io_uring/io_uring02.c b/testcases/kernel/syscalls/io_uring/io_uring02.c index c5c770074..026c52b1b 100644 --- a/testcases/kernel/syscalls/io_uring/io_uring02.c +++ b/testcases/kernel/syscalls/io_uring/io_uring02.c @@ -103,7 +103,7 @@ static void drain_fallback(void) sqe_ptr->opcode = IORING_OP_SENDMSG; sqe_ptr->flags = IOSQE_IO_DRAIN; sqe_ptr->fd = sockpair[0];

• sqe_ptr->addr = (__u64)&spam_header;
  

• sqe_ptr->addr = (uintptr_t)&spam_header;
  

  sqe_ptr->user_data = SPAM_MARK; uring.sqr_array[tail & *uring.sqr_mask] = i; }

@@ -113,7 +113,7 @@ static void drain_fallback(void) sqe_ptr->opcode = IORING_OP_SENDMSG; sqe_ptr->flags = IOSQE_IO_DRAIN; sqe_ptr->fd = sendsock;

• sqe_ptr->addr = (__u64)&beef_header;

• sqe_ptr->addr = (uintptr_t)&beef_header; sqe_ptr->user_data = BEEF_MARK; uring.sqr_array[tail & *uring.sqr_mask] = i; count = ++i;

@@ -218,7 +218,7 @@ static void run(void) sqe_ptr->opcode = IORING_OP_SENDMSG; sqe_ptr->flags = IOSQE_ASYNC; sqe_ptr->fd = sendsock;

• sqe_ptr->addr = (__u64)&beef_header;

• sqe_ptr->addr = (uintptr_t)&beef_header; sqe_ptr->user_data = BEEF_MARK; uring.sqr_array[tail & *uring.sqr_mask] = 0; tail++;