Commit a474d843 authored by Guo Weikang's avatar Guo Weikang Committed by Andrew Morton
Browse files

mm/shmem: refactor to reuse vfs_parse_monolithic_sep for option parsing 

shmem_parse_options() is refactored to use vfs_parse_monolithic_sep() with
a custom separator function, shmem_next_opt().  This eliminates redundant
logic for parsing comma-separated options and ensures consistency with
other kernel code that uses the same interface.

The vfs_parse_monolithic_sep() helper was introduced in commit
e001d144 ("fs: factor out vfs_parse_monolithic_sep() helper").

Link: https://lkml.kernel.org/r/20241205094521.1244678-1-guoweikang.kernel@gmail.com


Signed-off-by: default avatarGuo Weikang <guoweikang.kernel@gmail.com>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 19b65ffa

mm/shmem.c

+27 −38
Original line number Diff line number Diff line
@@ -4647,48 +4647,37 @@ static int shmem_parse_one(struct fs_context *fc, struct fs_parameter *param) 
	return invalfc(fc, "Bad value for '%s'", param->key);

}



static int shmem_parse_options(struct fs_context *fc, void *data)

static char *shmem_next_opt(char **s)

{

	char *options = data;

	char *sbegin = *s;

	char *p;



	if (options) {

		int err = security_sb_eat_lsm_opts(options, &fc->security);

		if (err)

			return err;

	}

	if (sbegin == NULL)

		return NULL;



	while (options != NULL) {

		char *this_char = options;

		for (;;) {

	/*

	 * NUL-terminate this option: unfortunately,

	 * mount options form a comma-separated list,

	 * but mpol's nodelist may also contain commas.

	 */

			options = strchr(options, ',');

			if (options == NULL)

				break;

			options++;

			if (!isdigit(*options)) {

				options[-1] = '\0';

	for (;;) {

		p = strchr(*s, ',');

		if (p == NULL)

			break;

		*s = p + 1;

		if (!isdigit(*(p+1))) {

			*p = '\0';

			return sbegin;

		}

	}

		if (*this_char) {

			char *value = strchr(this_char, '=');

			size_t len = 0;

			int err;



			if (value) {

				*value++ = '\0';

				len = strlen(value);

			}

			err = vfs_parse_fs_string(fc, this_char, value, len);

			if (err < 0)

				return err;

		}

	*s = NULL;

	return sbegin;

}

	return 0;



static int shmem_parse_monolithic(struct fs_context *fc, void *data)

{

	return vfs_parse_monolithic_sep(fc, data, shmem_next_opt);

}



/*
@@ -5038,7 +5027,7 @@ static const struct fs_context_operations shmem_fs_context_ops = { 
	.free			= shmem_free_fc,

	.get_tree		= shmem_get_tree,

#ifdef CONFIG_TMPFS

	.parse_monolithic	= shmem_parse_options,

	.parse_monolithic	= shmem_parse_monolithic,

	.parse_param		= shmem_parse_one,

	.reconfigure		= shmem_reconfigure,

#endif