On Tue, 28 Jun 2022 at 01:28, Qu Wenruo <w...@suse.com> wrote:
>
> This is to make sandboxfs to report blocksize it supports for
> _fs_read() to handle unaligned read.
>
> Unlike all other fses, sandboxfs can handle unaligned read/write without
> any problem since it's calling read()/write(), which doesn't bother the
> blocksize at all.
>
> This change is mostly to make testing of _fs_read() much easier.
>
> Cc: Simon Glass <s...@chromium.org>
> Signed-off-by: Qu Wenruo <w...@suse.com>
> ---
> arch/sandbox/cpu/os.c | 11 +++++++++++
> fs/fs.c | 2 +-
> fs/sandbox/sandboxfs.c | 14 ++++++++++++++
> include/os.h | 8 ++++++++
> include/sandboxfs.h | 1 +
> 5 files changed, 35 insertions(+), 1 deletion(-)
Reviewed-by: Simon Glass <s...@chromium.org>
with a comment as requested below
>
> diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
> index 5ea54179176c..6c29f29bdd9b 100644
> --- a/arch/sandbox/cpu/os.c
> +++ b/arch/sandbox/cpu/os.c
> @@ -46,6 +46,17 @@ ssize_t os_read(int fd, void *buf, size_t count)
> return read(fd, buf, count);
> }
>
> +ssize_t os_get_blocksize(int fd)
> +{
> + struct stat stat = {0};
> + int ret;
> +
> + ret = fstat(fd, &stat);
> + if (ret < 0)
> + return -errno;
> + return stat.st_blksize;
> +}
> +
> ssize_t os_write(int fd, const void *buf, size_t count)
> {
> return write(fd, buf, count);
> diff --git a/fs/fs.c b/fs/fs.c
> index 7e4ead9b790b..337d5711c28c 100644
> --- a/fs/fs.c
> +++ b/fs/fs.c
> @@ -261,7 +261,7 @@ static struct fstype_info fstypes[] = {
> .exists = sandbox_fs_exists,
> .size = sandbox_fs_size,
> .read = fs_read_sandbox,
> - .get_blocksize = fs_get_blocksize_unsupported,
> + .get_blocksize = sandbox_fs_get_blocksize,
> .write = fs_write_sandbox,
> .uuid = fs_uuid_unsupported,
> .opendir = fs_opendir_unsupported,
> diff --git a/fs/sandbox/sandboxfs.c b/fs/sandbox/sandboxfs.c
> index 4ae41d5b4db1..130fee088621 100644
> --- a/fs/sandbox/sandboxfs.c
> +++ b/fs/sandbox/sandboxfs.c
> @@ -55,6 +55,20 @@ int sandbox_fs_read_at(const char *filename, loff_t pos,
> void *buffer,
> return ret;
> }
>
> +int sandbox_fs_get_blocksize(const char *filename)
> +{
> + int fd;
> + int ret;
> +
> + fd = os_open(filename, OS_O_RDONLY);
> + if (fd < 0)
> + return fd;
> +
> + ret = os_get_blocksize(fd);
> + os_close(fd);
> + return ret;
> +}
> +
> int sandbox_fs_write_at(const char *filename, loff_t pos, void *buffer,
> loff_t towrite, loff_t *actwrite)
> {
> diff --git a/include/os.h b/include/os.h
> index 10e198cf503e..a864d9ca39b2 100644
> --- a/include/os.h
> +++ b/include/os.h
> @@ -26,6 +26,14 @@ struct sandbox_state;
> */
> ssize_t os_read(int fd, void *buf, size_t count);
>
> +/**
> + * Get the optimial blocksize through stat() call.
> + *
> + * @fd: File descriptor as returned by os_open()
> + * Return: >=0 for the blocksize. <0 for error.
> + */
> +ssize_t os_get_blocksize(int fd);
> +
> /**
> * Access to the OS write() system call
> *
> diff --git a/include/sandboxfs.h b/include/sandboxfs.h
> index 783dd5c88a73..6937068f7b82 100644
> --- a/include/sandboxfs.h
> +++ b/include/sandboxfs.h
> @@ -32,6 +32,7 @@ void sandbox_fs_close(void);
> int sandbox_fs_ls(const char *dirname);
> int sandbox_fs_exists(const char *filename);
> int sandbox_fs_size(const char *filename, loff_t *size);
> +int sandbox_fs_get_blocksize(const char *filename);
Please add a full comment.
> int fs_read_sandbox(const char *filename, void *buf, loff_t offset, loff_t
> len,
> loff_t *actread);
> int fs_write_sandbox(const char *filename, void *buf, loff_t offset,
> --
> 2.36.1
>
Regards,
Simon
