[LTP] [PATCH v1] io_submit05.c: Add test case for RWF_APPEND flag

[Andrea Cervesato]

Hi!

On 11/10/23 12:58, Wei Gao via ltp wrote:
> Signed-off-by: Wei Gao <wegao@suse.com>
> ---
> runtest/syscalls                              |   1 +
> .../kernel/syscalls/io_submit/.gitignore      |   1 +
> .../kernel/syscalls/io_submit/io_submit05.c   | 123 ++++++++++++++++++
> 3 files changed, 125 insertions(+)
> create mode 100644 testcases/kernel/syscalls/io_submit/io_submit05.c
>
> diff --git a/runtest/syscalls b/runtest/syscalls
> index c7a0b2301..15a54f2d3 100644
> --- a/runtest/syscalls
> +++ b/runtest/syscalls
> @@ -656,6 +656,7 @@ io_setup02 io_setup02
> io_submit01 io_submit01
> io_submit02 io_submit02
> io_submit03 io_submit03
> +io_submit05 io_submit05
>
> keyctl01 keyctl01
> keyctl02 keyctl02
> diff --git a/testcases/kernel/syscalls/io_submit/.gitignore 
> b/testcases/kernel/syscalls/io_submit/.gitignore
> index 60b07970a..cf0d4c6df 100644
> --- a/testcases/kernel/syscalls/io_submit/.gitignore
> +++ b/testcases/kernel/syscalls/io_submit/.gitignore
> @@ -1,3 +1,4 @@
> /io_submit01
> /io_submit02
> /io_submit03
> +/io_submit05
> diff --git a/testcases/kernel/syscalls/io_submit/io_submit05.c 
> b/testcases/kernel/syscalls/io_submit/io_submit05.c
> new file mode 100644
> index 000000000..32f4379e1
> --- /dev/null
> +++ b/testcases/kernel/syscalls/io_submit/io_submit05.c
> @@ -0,0 +1,123 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (c) 2023 Wei Gao <wegao@suse.com>
> + */
> +
> +/*\
> + * [Description]
> + *
> + * This is a basic test for io_submit RWF_APPEND flag.
> + *
> + */
> +
> +#include <linux/aio_abi.h>
> +
> +#include "config.h"
> +#include "tst_test.h"
> +#include "tst_safe_pthread.h"
> +#include "lapi/syscalls.h"
> +
> +#define TEST_FILE "test_file"
> +#define MODE 0777
> +#define BUF_LEN 10
> +#define MNTPOINT "mntpoint"
> +
> +static char *init_buf;
> +static char *update_buf;
> +static char *tmp_buf;
> +static int fd;
> +static aio_context_t ctx;
> +static struct iocb iocb;
> +static struct iocb *iocbs[] = {&iocb};
> +static volatile int stop;
> +
> +static inline void io_prep_option(struct iocb *cb, int fd, void *buf,
> +            size_t count, long long offset, unsigned int opcode)
> +{
> +    memset(cb, 0, sizeof(*cb));
> +    cb->aio_fildes = fd;
> +    cb->aio_lio_opcode = opcode;
> +    cb->aio_buf = (uint64_t)buf;
> +    cb->aio_offset = offset;
> +    cb->aio_nbytes = count;
> +    cb->aio_rw_flags = RWF_APPEND;
> +}
> +
> +static unsigned int io_submit(void)
> +{
> +    struct io_event evbuf;
> +    struct timespec timeout = { .tv_sec = 1 };
> +
> +    TST_EXP_VAL_SILENT(tst_syscall(__NR_io_submit, ctx, 1, iocbs), 1);
> +    TST_EXP_VAL_SILENT(tst_syscall(__NR_io_getevents, ctx, 1, 1, &evbuf,
> +            &timeout), 1);
> +}
This function has not return value, so it should be defined as "static 
void io_submit(void)".
> +
> +static void setup(void)
> +{
Empty space to remove.
>
> +
> +    TST_EXP_PASS_SILENT(tst_syscall(__NR_io_setup, 1, &ctx));
> +
> +    fd = SAFE_OPEN(TEST_FILE, O_RDWR | O_CREAT, MODE);
> +    SAFE_LSEEK(fd, 0, SEEK_SET);
> +
> +    memset(init_buf, 0x62, BUF_LEN);
> +    memset(update_buf, 0x61, BUF_LEN);
> +    memset(tmp_buf, 0, BUF_LEN);
> +
> +    io_prep_option(&iocb, fd, update_buf, BUF_LEN, 1, IOCB_CMD_PWRITE);
> +}
> +
> +static void cleanup(void)
> +{
> +    if (fd > 0)
> +        SAFE_CLOSE(fd);
> +
> +    if (tst_syscall(__NR_io_destroy, ctx))
> +        tst_brk(TBROK | TERRNO, "io_destroy() failed");
> +}
> +
> +
> +static void run(void)
> +{
> +    int i;
> +
> +    SAFE_WRITE(0, fd, init_buf, BUF_LEN);
> +    io_submit();
> +    SAFE_LSEEK(fd, BUF_LEN, SEEK_SET);
> +    SAFE_READ(1, fd, tmp_buf, BUF_LEN);
> +    for (i = 0; i < BUF_LEN; i++) {
> +        if (tmp_buf[i] != 0x61)
> +            break;
> +    }
> +
> +    if (i != BUF_LEN) {
> +        tst_res(TFAIL, "buffer wrong at %i have %c expected 'a'",
> +                i, tmp_buf[i]);
> +        return;
> +    }
> +
> +    tst_res(TPASS, "io_submit wrote %zi bytes successfully "
> +            "with content 'a' expectedly ", BUF_LEN);
We need to use %d instead of %zi.
> +}
> +
> +static struct tst_test test = {
> +    .needs_tmpdir = 1,
> +    .needs_kconfigs = (const char *[]) {
> +        "CONFIG_AIO=y",
> +        NULL
> +    },
> +    .setup = setup,
> +    .cleanup = cleanup,
> +    .test_all = run,
> +    .max_runtime = 60,
> +    .mntpoint = MNTPOINT,
> +    .mount_device = 1,
> +    .all_filesystems = 1,
We don't need to mount any folder and to test on multiple filesystems, 
since we are testing a regular syscall feature which is unrelated with 
the specific filesystem.
> +    .bufs = (struct tst_buffers []) {
> +        {&init_buf, .size = BUF_LEN},
> +        {&update_buf, .size = BUF_LEN},
> +        {&tmp_buf, .size = BUF_LEN},
> +        {}
> +    }
> +};

I generally think this test doesn't test the feature in a proper way. 
The meaning of the RWF_APPEND flag is that we asynchronously append data 
to a file, but in this case we only check that data has been appended at 
the start of the file, since we call lseek(fd, 0, SEEK_SET) first.

It would be probably more interesting to generate a file, then call the 
io_submit syscall with RWF_APPEND flag and to check that data has been 
actually appended to the file in a correct way.

Regards,
Andrea Cervesato