From 50ac2d694f2dd1658341cf97bcf2ffb836d772cb Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 12 Aug 2008 15:09:02 -0700 Subject: seq_file: add seq_cpumask(), seq_nodemask() Short enough reads from /proc/irq/*/smp_affinity return -EINVAL for no good reason. This became noticed with NR_CPUS=4096 patches, when length of printed representation of cpumask becase 1152, but cat(1) continued to read with 1024-byte chunks. bitmap_scnprintf() in good faith fills buffer, returns 1023, check returns -EINVAL. Fix it by switching to seq_file, so handler will just fill buffer and doesn't care about offsets, length, filling EOF and all this crap. For that add seq_bitmap(), and wrappers around it -- seq_cpumask() and seq_nodemask(). Signed-off-by: Alexey Dobriyan Reviewed-by: Paul Jackson Cc: Mike Travis Cc: Al Viro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/bitmap.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'lib') diff --git a/lib/bitmap.c b/lib/bitmap.c index 482df94ea21..06fb57c86de 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -315,6 +315,17 @@ int bitmap_scnprintf(char *buf, unsigned int buflen, } EXPORT_SYMBOL(bitmap_scnprintf); +/** + * bitmap_scnprintf_len - return buffer length needed to convert + * bitmap to an ASCII hex string + * @nr_bits: number of bits to be converted + */ +int bitmap_scnprintf_len(unsigned int nr_bits) +{ + unsigned int nr_nibbles = ALIGN(nr_bits, 4) / 4; + return nr_nibbles + ALIGN(nr_nibbles, CHUNKSZ / 4) / (CHUNKSZ / 4) - 1; +} + /** * __bitmap_parse - convert an ASCII hex string into a bitmap. * @buf: pointer to buffer containing string. -- cgit v1.2.3