bitmap_scnprintf_len() returns 36 (thirty six) for NR_CPUS=2 which is
ridiculous. So, rewrite the whole thing. Fixed version allows correct
seq_bitmap/seq_cpumask.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---
include/linux/bitmap.h | 2 +-
lib/bitmap.c | 12 ++++--------
2 files changed, 5 insertions(+), 9 deletions(-)
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -110,7 +110,7 @@ extern int __bitmap_weight(const unsigned long *bitmap, int bits);
extern int bitmap_scnprintf(char *buf, unsigned int len,
const unsigned long *src, int nbits);
-extern int bitmap_scnprintf_len(unsigned int len);
+extern int bitmap_scnprintf_len(unsigned int nr_bits);
extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user,
unsigned long *dst, int nbits);
extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -318,16 +318,12 @@ EXPORT_SYMBOL(bitmap_scnprintf);
/**
* bitmap_scnprintf_len - return buffer length needed to convert
* bitmap to an ASCII hex string.
- * @len: number of bits to be converted
+ * @nr_bits: number of bits to be converted
*/
-int bitmap_scnprintf_len(unsigned int len)
+int bitmap_scnprintf_len(unsigned int nr_bits)
{
- /* we need 9 chars per word for 32 bit words (8 hexdigits + sep/null) */
- int bitslen = ALIGN(len, CHUNKSZ);
- int wordlen = CHUNKSZ / 4;
- int buflen = (bitslen / wordlen) * (wordlen + 1) * sizeof(char);
-
- return buflen;
+ unsigned int nr_nibbles = ALIGN(nr_bits, 4) / 4;
+ return nr_nibbles + ALIGN(nr_nibbles, CHUNKSZ / 4) / (CHUNKSZ / 4) - 1;
}
EXPORT_SYMBOL(bitmap_scnprintf_len);
--
