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author | Alexey Dobriyan <adobriyan@gmail.com> | 2008-08-13 00:09:02 +0200 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-08-13 01:07:30 +0200 |
commit | 50ac2d694f2dd1658341cf97bcf2ffb836d772cb (patch) | |
tree | c4466ecb7c5211ee9423380783f00027411d5d5a | |
parent | reiserfs: removed duplicated #include (diff) | |
download | linux-50ac2d694f2dd1658341cf97bcf2ffb836d772cb.tar.xz linux-50ac2d694f2dd1658341cf97bcf2ffb836d772cb.zip |
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 <adobriyan@gmail.com>
Reviewed-by: Paul Jackson <pj@sgi.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | fs/seq_file.c | 14 | ||||
-rw-r--r-- | include/linux/bitmap.h | 1 | ||||
-rw-r--r-- | include/linux/seq_file.h | 12 | ||||
-rw-r--r-- | lib/bitmap.c | 11 |
4 files changed, 38 insertions, 0 deletions
diff --git a/fs/seq_file.c b/fs/seq_file.c index 3f54dbd6c49b..5d54205e486b 100644 --- a/fs/seq_file.c +++ b/fs/seq_file.c @@ -443,6 +443,20 @@ int seq_dentry(struct seq_file *m, struct dentry *dentry, char *esc) return -1; } +int seq_bitmap(struct seq_file *m, unsigned long *bits, unsigned int nr_bits) +{ + size_t len = bitmap_scnprintf_len(nr_bits); + + if (m->count + len < m->size) { + bitmap_scnprintf(m->buf + m->count, m->size - m->count, + bits, nr_bits); + m->count += len; + return 0; + } + m->count = m->size; + return -1; +} + static void *single_start(struct seq_file *p, loff_t *pos) { return NULL + (*pos == 0); diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 1abfe664c444..89781fd48859 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -110,6 +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 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, diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h index a66304a09955..a1783b229ef4 100644 --- a/include/linux/seq_file.h +++ b/include/linux/seq_file.h @@ -4,6 +4,8 @@ #include <linux/types.h> #include <linux/string.h> #include <linux/mutex.h> +#include <linux/cpumask.h> +#include <linux/nodemask.h> struct seq_operations; struct file; @@ -47,6 +49,16 @@ int seq_path(struct seq_file *, struct path *, char *); int seq_dentry(struct seq_file *, struct dentry *, char *); int seq_path_root(struct seq_file *m, struct path *path, struct path *root, char *esc); +int seq_bitmap(struct seq_file *m, unsigned long *bits, unsigned int nr_bits); +static inline int seq_cpumask(struct seq_file *m, cpumask_t *mask) +{ + return seq_bitmap(m, mask->bits, NR_CPUS); +} + +static inline int seq_nodemask(struct seq_file *m, nodemask_t *mask) +{ + return seq_bitmap(m, mask->bits, MAX_NUMNODES); +} int single_open(struct file *, int (*)(struct seq_file *, void *), void *); int single_release(struct inode *, struct file *); diff --git a/lib/bitmap.c b/lib/bitmap.c index 482df94ea21e..06fb57c86de0 100644 --- a/lib/bitmap.c +++ b/lib/bitmap.c @@ -316,6 +316,17 @@ 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. * @buflen: buffer size in bytes. If string is smaller than this |