lib: rework bitmap_parselist
Remove __bitmap_parselist helper and split the function to logical parts. [ynorov@marvell.com: v5] Link: http://lkml.kernel.org/r/20190416063801.20134-3-ynorov@marvell.com Link: http://lkml.kernel.org/r/20190405173211.11373-3-ynorov@marvell.com Signed-off-by: Yury Norov <ynorov@marvell.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Travis <travis@sgi.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Yury Norov
Linus Torvalds
parent
281327c99b
commit
e371c481d8
255
lib/bitmap.c
255
lib/bitmap.c
|
|
@ -20,6 +20,8 @@
|
|||
|
||||
#include <asm/page.h>
|
||||
|
||||
#include "kstrtox.h"
|
||||
|
||||
/**
|
||||
* DOC: bitmap introduction
|
||||
*
|
||||
|
|
@ -477,12 +479,128 @@ int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
|
|||
}
|
||||
EXPORT_SYMBOL(bitmap_print_to_pagebuf);
|
||||
|
||||
/*
|
||||
* Region 9-38:4/10 describes the following bitmap structure:
|
||||
* 0 9 12 18 38
|
||||
* .........****......****......****......
|
||||
* ^ ^ ^ ^
|
||||
* start off group_len end
|
||||
*/
|
||||
struct region {
|
||||
unsigned int start;
|
||||
unsigned int off;
|
||||
unsigned int group_len;
|
||||
unsigned int end;
|
||||
};
|
||||
|
||||
static int bitmap_set_region(const struct region *r,
|
||||
unsigned long *bitmap, int nbits)
|
||||
{
|
||||
unsigned int start;
|
||||
|
||||
if (r->end >= nbits)
|
||||
return -ERANGE;
|
||||
|
||||
for (start = r->start; start <= r->end; start += r->group_len)
|
||||
bitmap_set(bitmap, start, min(r->end - start + 1, r->off));
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int bitmap_check_region(const struct region *r)
|
||||
{
|
||||
if (r->start > r->end || r->group_len == 0 || r->off > r->group_len)
|
||||
return -EINVAL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const char *bitmap_getnum(const char *str, unsigned int *num)
|
||||
{
|
||||
unsigned long long n;
|
||||
unsigned int len;
|
||||
|
||||
len = _parse_integer(str, 10, &n);
|
||||
if (!len)
|
||||
return ERR_PTR(-EINVAL);
|
||||
if (len & KSTRTOX_OVERFLOW || n != (unsigned int)n)
|
||||
return ERR_PTR(-EOVERFLOW);
|
||||
|
||||
*num = n;
|
||||
return str + len;
|
||||
}
|
||||
|
||||
static inline bool end_of_str(char c)
|
||||
{
|
||||
return c == '\0' || c == '\n';
|
||||
}
|
||||
|
||||
static inline bool __end_of_region(char c)
|
||||
{
|
||||
return isspace(c) || c == ',';
|
||||
}
|
||||
|
||||
static inline bool end_of_region(char c)
|
||||
{
|
||||
return __end_of_region(c) || end_of_str(c);
|
||||
}
|
||||
|
||||
/*
|
||||
* The format allows commas and whitespases at the beginning
|
||||
* of the region.
|
||||
*/
|
||||
static const char *bitmap_find_region(const char *str)
|
||||
{
|
||||
while (__end_of_region(*str))
|
||||
str++;
|
||||
|
||||
return end_of_str(*str) ? NULL : str;
|
||||
}
|
||||
|
||||
static const char *bitmap_parse_region(const char *str, struct region *r)
|
||||
{
|
||||
str = bitmap_getnum(str, &r->start);
|
||||
if (IS_ERR(str))
|
||||
return str;
|
||||
|
||||
if (end_of_region(*str))
|
||||
goto no_end;
|
||||
|
||||
if (*str != '-')
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
str = bitmap_getnum(str + 1, &r->end);
|
||||
if (IS_ERR(str))
|
||||
return str;
|
||||
|
||||
if (end_of_region(*str))
|
||||
goto no_pattern;
|
||||
|
||||
if (*str != ':')
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
str = bitmap_getnum(str + 1, &r->off);
|
||||
if (IS_ERR(str))
|
||||
return str;
|
||||
|
||||
if (*str != '/')
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
return bitmap_getnum(str + 1, &r->group_len);
|
||||
|
||||
no_end:
|
||||
r->end = r->start;
|
||||
no_pattern:
|
||||
r->off = r->end + 1;
|
||||
r->group_len = r->end + 1;
|
||||
|
||||
return end_of_str(*str) ? NULL : str;
|
||||
}
|
||||
|
||||
/**
|
||||
* __bitmap_parselist - convert list format ASCII string to bitmap
|
||||
* @buf: read nul-terminated user string from this buffer
|
||||
* @buflen: buffer size in bytes. If string is smaller than this
|
||||
* then it must be terminated with a \0.
|
||||
* @is_user: location of buffer, 0 indicates kernel space
|
||||
* bitmap_parselist - convert list format ASCII string to bitmap
|
||||
* @buf: read user string from this buffer; must be terminated
|
||||
* with a \0 or \n.
|
||||
* @maskp: write resulting mask here
|
||||
* @nmaskbits: number of bits in mask to be written
|
||||
*
|
||||
|
|
@ -498,127 +616,38 @@ EXPORT_SYMBOL(bitmap_print_to_pagebuf);
|
|||
*
|
||||
* Returns: 0 on success, -errno on invalid input strings. Error values:
|
||||
*
|
||||
* - ``-EINVAL``: second number in range smaller than first
|
||||
* - ``-EINVAL``: wrong region format
|
||||
* - ``-EINVAL``: invalid character in string
|
||||
* - ``-ERANGE``: bit number specified too large for mask
|
||||
* - ``-EOVERFLOW``: integer overflow in the input parameters
|
||||
*/
|
||||
static int __bitmap_parselist(const char *buf, unsigned int buflen,
|
||||
int is_user, unsigned long *maskp,
|
||||
int nmaskbits)
|
||||
int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits)
|
||||
{
|
||||
unsigned int a, b, old_a, old_b;
|
||||
unsigned int group_size, used_size, off;
|
||||
int c, old_c, totaldigits, ndigits;
|
||||
const char __user __force *ubuf = (const char __user __force *)buf;
|
||||
int at_start, in_range, in_partial_range;
|
||||
struct region r;
|
||||
long ret;
|
||||
|
||||
totaldigits = c = 0;
|
||||
old_a = old_b = 0;
|
||||
group_size = used_size = 0;
|
||||
bitmap_zero(maskp, nmaskbits);
|
||||
do {
|
||||
at_start = 1;
|
||||
in_range = 0;
|
||||
in_partial_range = 0;
|
||||
a = b = 0;
|
||||
ndigits = totaldigits;
|
||||
|
||||
/* Get the next cpu# or a range of cpu#'s */
|
||||
while (buflen) {
|
||||
old_c = c;
|
||||
if (is_user) {
|
||||
if (__get_user(c, ubuf++))
|
||||
return -EFAULT;
|
||||
} else
|
||||
c = *buf++;
|
||||
buflen--;
|
||||
if (isspace(c))
|
||||
continue;
|
||||
while (buf) {
|
||||
buf = bitmap_find_region(buf);
|
||||
if (buf == NULL)
|
||||
return 0;
|
||||
|
||||
/* A '\0' or a ',' signal the end of a cpu# or range */
|
||||
if (c == '\0' || c == ',')
|
||||
break;
|
||||
/*
|
||||
* whitespaces between digits are not allowed,
|
||||
* but it's ok if whitespaces are on head or tail.
|
||||
* when old_c is whilespace,
|
||||
* if totaldigits == ndigits, whitespace is on head.
|
||||
* if whitespace is on tail, it should not run here.
|
||||
* as c was ',' or '\0',
|
||||
* the last code line has broken the current loop.
|
||||
*/
|
||||
if ((totaldigits != ndigits) && isspace(old_c))
|
||||
return -EINVAL;
|
||||
buf = bitmap_parse_region(buf, &r);
|
||||
if (IS_ERR(buf))
|
||||
return PTR_ERR(buf);
|
||||
|
||||
if (c == '/') {
|
||||
used_size = a;
|
||||
at_start = 1;
|
||||
in_range = 0;
|
||||
a = b = 0;
|
||||
continue;
|
||||
}
|
||||
ret = bitmap_check_region(&r);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (c == ':') {
|
||||
old_a = a;
|
||||
old_b = b;
|
||||
at_start = 1;
|
||||
in_range = 0;
|
||||
in_partial_range = 1;
|
||||
a = b = 0;
|
||||
continue;
|
||||
}
|
||||
ret = bitmap_set_region(&r, maskp, nmaskbits);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
if (c == '-') {
|
||||
if (at_start || in_range)
|
||||
return -EINVAL;
|
||||
b = 0;
|
||||
in_range = 1;
|
||||
at_start = 1;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (!isdigit(c))
|
||||
return -EINVAL;
|
||||
|
||||
b = b * 10 + (c - '0');
|
||||
if (!in_range)
|
||||
a = b;
|
||||
at_start = 0;
|
||||
totaldigits++;
|
||||
}
|
||||
if (ndigits == totaldigits)
|
||||
continue;
|
||||
if (in_partial_range) {
|
||||
group_size = a;
|
||||
a = old_a;
|
||||
b = old_b;
|
||||
old_a = old_b = 0;
|
||||
} else {
|
||||
used_size = group_size = b - a + 1;
|
||||
}
|
||||
/* if no digit is after '-', it's wrong*/
|
||||
if (at_start && in_range)
|
||||
return -EINVAL;
|
||||
if (!(a <= b) || group_size == 0 || !(used_size <= group_size))
|
||||
return -EINVAL;
|
||||
if (b >= nmaskbits)
|
||||
return -ERANGE;
|
||||
while (a <= b) {
|
||||
off = min(b - a + 1, used_size);
|
||||
bitmap_set(maskp, a, off);
|
||||
a += group_size;
|
||||
}
|
||||
} while (buflen && c == ',');
|
||||
return 0;
|
||||
}
|
||||
|
||||
int bitmap_parselist(const char *bp, unsigned long *maskp, int nmaskbits)
|
||||
{
|
||||
char *nl = strchrnul(bp, '\n');
|
||||
int len = nl - bp;
|
||||
|
||||
return __bitmap_parselist(bp, len, 0, maskp, nmaskbits);
|
||||
}
|
||||
EXPORT_SYMBOL(bitmap_parselist);
|
||||
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue