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authorLinus Torvalds <torvalds@linux-foundation.org>2009-04-24 08:27:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-04-24 08:27:02 -0700
commit12bac708e6242b0ccd969519582b2938d78289bb (patch)
tree4cf804bcf1a3afb90044f8b33405ea6713c8731e /include
parent60911731fe7fd4ec4d088fc1a48a56c9fb14103f (diff)
parentd9ba7615bfd8bb06f79c853f9dfff9e93a837941 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes: GFS2: Ensure that the inode goal block settings are updated GFS2: Fix bug in block allocation bitops: Add __ffs64 bitop
Diffstat (limited to 'include')
-rw-r--r--include/linux/bitops.h19
1 files changed, 19 insertions, 0 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h
index 61829139795..c05a29cb9bb 100644
--- a/include/linux/bitops.h
+++ b/include/linux/bitops.h
@@ -112,6 +112,25 @@ static inline unsigned fls_long(unsigned long l)
return fls64(l);
}
+/**
+ * __ffs64 - find first set bit in a 64 bit word
+ * @word: The 64 bit word
+ *
+ * On 64 bit arches this is a synomyn for __ffs
+ * The result is not defined if no bits are set, so check that @word
+ * is non-zero before calling this.
+ */
+static inline unsigned long __ffs64(u64 word)
+{
+#if BITS_PER_LONG == 32
+ if (((u32)word) == 0UL)
+ return __ffs((u32)(word >> 32)) + 32;
+#elif BITS_PER_LONG != 64
+#error BITS_PER_LONG not 32 or 64
+#endif
+ return __ffs((unsigned long)word);
+}
+
#ifdef __KERNEL__
#ifdef CONFIG_GENERIC_FIND_FIRST_BIT