Merge tag 'regmap-3.4' into regmap-stride

regmap: Last minute bug fix for 3.4

This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used.  The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.

Conflicts:
	drivers/base/regmap/regmap.c (overlap between the fix and stride code)

1 files changed, 22 insertions, 4 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index b60ddc41d78..b80531c9177 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -141,18 +141,29 @@ int proc_nr_dentry(ctl_table *table, int write, void __user *buffer,
  * Compare 2 name strings, return 0 if they match, otherwise non-zero.
  * The strings are both count bytes long, and count is non-zero.
  */
+#ifdef CONFIG_DCACHE_WORD_ACCESS
+
+#include <asm/word-at-a-time.h>
+/*
+ * NOTE! 'cs' and 'scount' come from a dentry, so it has a
+ * aligned allocation for this particular component. We don't
+ * strictly need the load_unaligned_zeropad() safety, but it
+ * doesn't hurt either.
+ *
+ * In contrast, 'ct' and 'tcount' can be from a pathname, and do
+ * need the careful unaligned handling.
+ */
 static inline int dentry_cmp(const unsigned char *cs, size_t scount,
 				const unsigned char *ct, size_t tcount)
 {
-#ifdef CONFIG_DCACHE_WORD_ACCESS
 	unsigned long a,b,mask;
 
 	if (unlikely(scount != tcount))
 		return 1;
 
 	for (;;) {
-		a = *(unsigned long *)cs;
-		b = *(unsigned long *)ct;
+		a = load_unaligned_zeropad(cs);
+		b = load_unaligned_zeropad(ct);
 		if (tcount < sizeof(unsigned long))
 			break;
 		if (unlikely(a != b))
@@ -165,7 +176,13 @@ static inline int dentry_cmp(const unsigned char *cs, size_t scount,
 	}
 	mask = ~(~0ul << tcount*8);
 	return unlikely(!!((a ^ b) & mask));
+}
+
 #else
+
+static inline int dentry_cmp(const unsigned char *cs, size_t scount,
+				const unsigned char *ct, size_t tcount)
+{
 	if (scount != tcount)
 		return 1;
 
@@ -177,9 +194,10 @@ static inline int dentry_cmp(const unsigned char *cs, size_t scount,
 		tcount--;
 	} while (tcount);
 	return 0;
-#endif
 }
 
+#endif
+
 static void __d_free(struct rcu_head *head)
 {
 	struct dentry *dentry = container_of(head, struct dentry, d_u.d_rcu);