#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/kernel.h>
+#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/uaccess.h>
* carefully filter out these unused bits from impacting their
* results.
*
- * These operations actually hold to a slightly stronger rule:
- * if you don't input any bitmaps to these ops that have some
- * unused bits set, then they won't output any set unused bits
- * in output bitmaps.
- *
* The byte ordering of bitmaps is more natural on little
* endian architectures. See the big-endian headers
* include/asm-ppc64/bitops.h and include/asm-s390/bitops.h
* ranges if list is specified or hex digits grouped into comma-separated
* sets of 8 digits/set. Returns the number of characters written to buf.
*
- * It is assumed that @buf is a pointer into a PAGE_SIZE area and that
- * sufficient storage remains at @buf to accommodate the
- * bitmap_print_to_pagebuf() output.
+ * It is assumed that @buf is a pointer into a PAGE_SIZE, page-aligned
+ * area and that sufficient storage remains at @buf to accommodate the
+ * bitmap_print_to_pagebuf() output. Returns the number of characters
+ * actually printed to @buf, excluding terminating '\0'.
*/
int bitmap_print_to_pagebuf(bool list, char *buf, const unsigned long *maskp,
int nmaskbits)
{
- ptrdiff_t len = PTR_ALIGN(buf + PAGE_SIZE - 1, PAGE_SIZE) - buf;
- int n = 0;
+ ptrdiff_t len = PAGE_SIZE - offset_in_page(buf);
- if (len > 1)
- n = list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) :
- scnprintf(buf, len, "%*pb\n", nmaskbits, maskp);
- return n;
+ return list ? scnprintf(buf, len, "%*pbl\n", nmaskbits, maskp) :
+ scnprintf(buf, len, "%*pb\n", nmaskbits, maskp);
}
EXPORT_SYMBOL(bitmap_print_to_pagebuf);