diff options
Diffstat (limited to 'lib/bitmap.c')
| -rw-r--r-- | lib/bitmap.c | 49 |
1 files changed, 29 insertions, 20 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c index 75006c4036e9..9f4626a4c95f 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -487,30 +487,25 @@ 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 + * 0 9 12 18 38 N + * .........****......****......****.................. + * ^ ^ ^ ^ ^ + * start off group_len end nbits */ struct region { unsigned int start; unsigned int off; unsigned int group_len; unsigned int end; + unsigned int nbits; }; -static int bitmap_set_region(const struct region *r, - unsigned long *bitmap, int nbits) +static void bitmap_set_region(const struct region *r, unsigned long *bitmap) { 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) @@ -518,14 +513,23 @@ 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; + if (r->end >= r->nbits) + return -ERANGE; + return 0; } -static const char *bitmap_getnum(const char *str, unsigned int *num) +static const char *bitmap_getnum(const char *str, unsigned int *num, + unsigned int lastbit) { unsigned long long n; unsigned int len; + if (str[0] == 'N') { + *num = lastbit; + return str + 1; + } + len = _parse_integer(str, 10, &n); if (!len) return ERR_PTR(-EINVAL); @@ -573,7 +577,9 @@ static const char *bitmap_find_region_reverse(const char *start, const char *end static const char *bitmap_parse_region(const char *str, struct region *r) { - str = bitmap_getnum(str, &r->start); + unsigned int lastbit = r->nbits - 1; + + str = bitmap_getnum(str, &r->start, lastbit); if (IS_ERR(str)) return str; @@ -583,7 +589,7 @@ static const char *bitmap_parse_region(const char *str, struct region *r) if (*str != '-') return ERR_PTR(-EINVAL); - str = bitmap_getnum(str + 1, &r->end); + str = bitmap_getnum(str + 1, &r->end, lastbit); if (IS_ERR(str)) return str; @@ -593,14 +599,14 @@ static const char *bitmap_parse_region(const char *str, struct region *r) if (*str != ':') return ERR_PTR(-EINVAL); - str = bitmap_getnum(str + 1, &r->off); + str = bitmap_getnum(str + 1, &r->off, lastbit); if (IS_ERR(str)) return str; if (*str != '/') return ERR_PTR(-EINVAL); - return bitmap_getnum(str + 1, &r->group_len); + return bitmap_getnum(str + 1, &r->group_len, lastbit); no_end: r->end = r->start; @@ -627,6 +633,10 @@ no_pattern: * From each group will be used only defined amount of bits. * Syntax: range:used_size/group_size * Example: 0-1023:2/256 ==> 0,1,256,257,512,513,768,769 + * The value 'N' can be used as a dynamically substituted token for the + * maximum allowed value; i.e (nmaskbits - 1). Keep in mind that it is + * dynamic, so if system changes cause the bitmap width to change, such + * as more cores in a CPU list, then any ranges using N will also change. * * Returns: 0 on success, -errno on invalid input strings. Error values: * @@ -640,7 +650,8 @@ int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) struct region r; long ret; - bitmap_zero(maskp, nmaskbits); + r.nbits = nmaskbits; + bitmap_zero(maskp, r.nbits); while (buf) { buf = bitmap_find_region(buf); @@ -655,9 +666,7 @@ int bitmap_parselist(const char *buf, unsigned long *maskp, int nmaskbits) if (ret) return ret; - ret = bitmap_set_region(&r, maskp, nmaskbits); - if (ret) - return ret; + bitmap_set_region(&r, maskp); } return 0; |