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Diffstat (limited to 'lib/bitmap.c')
-rw-r--r--lib/bitmap.c35
1 files changed, 11 insertions, 24 deletions
diff --git a/lib/bitmap.c b/lib/bitmap.c
index 730969c681cb..98872e9025da 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -13,6 +13,7 @@
#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>
@@ -36,11 +37,6 @@
* 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
@@ -447,7 +443,7 @@ int bitmap_parse_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
- if (!access_ok(VERIFY_READ, ubuf, ulen))
+ if (!access_ok(ubuf, ulen))
return -EFAULT;
return __bitmap_parse((const char __force *)ubuf,
ulen, 1, maskp, nmaskbits);
@@ -466,20 +462,18 @@ EXPORT_SYMBOL(bitmap_parse_user);
* 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);
@@ -647,7 +641,7 @@ int bitmap_parselist_user(const char __user *ubuf,
unsigned int ulen, unsigned long *maskp,
int nmaskbits)
{
- if (!access_ok(VERIFY_READ, ubuf, ulen))
+ if (!access_ok(ubuf, ulen))
return -EFAULT;
return __bitmap_parselist((const char __force *)ubuf,
ulen, 1, maskp, nmaskbits);
@@ -1152,14 +1146,10 @@ EXPORT_SYMBOL(bitmap_free);
* @buf: array of u32 (in host byte order), the source bitmap
* @nbits: number of bits in @bitmap
*/
-void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf,
- unsigned int nbits)
+void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf, unsigned int nbits)
{
unsigned int i, halfwords;
- if (!nbits)
- return;
-
halfwords = DIV_ROUND_UP(nbits, 32);
for (i = 0; i < halfwords; i++) {
bitmap[i/2] = (unsigned long) buf[i];
@@ -1183,9 +1173,6 @@ void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap, unsigned int nbits)
{
unsigned int i, halfwords;
- if (!nbits)
- return;
-
halfwords = DIV_ROUND_UP(nbits, 32);
for (i = 0; i < halfwords; i++) {
buf[i] = (u32) (bitmap[i/2] & UINT_MAX);