Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=218e180e7ea5334e1f94121940ba82cd1f0f4e58
Commit: 218e180e7ea5334e1f94121940ba82cd1f0f4e58
Parent: 894b8788d7f265eb7c6f75a9a77cedeb48f51586
Author: Andrew Morton <[EMAIL PROTECTED]>
AuthorDate: Thu May 10 03:15:18 2007 -0700
Committer: Linus Torvalds <[EMAIL PROTECTED]>
CommitDate: Thu May 10 09:26:52 2007 -0700
add upper-32-bits macro
We keep on getting "right shift count >= width of type" warnings when doing
things like
sector_t s;
x = s >> 56;
because with CONFIG_LBD=n, s is only 32-bit. Similar problems can occur
with
dma_addr_t's.
So add a simple wrapper function which code can use to avoid this warning.
The above example would become
x = upper_32_bits(s) >> 24;
The first user is in fact AFS.
Cc: James Bottomley <[EMAIL PROTECTED]>
Cc: "Cameron, Steve" <[EMAIL PROTECTED]>
Cc: "Miller, Mike (OS Dev)" <[EMAIL PROTECTED]>
Cc: Hisashi Hifumi <[EMAIL PROTECTED]>
Cc: Alan Cox <[EMAIL PROTECTED]>
Cc: David Howells <[EMAIL PROTECTED]>
Signed-off-by: Andrew Morton <[EMAIL PROTECTED]>
Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]>
---
include/linux/kernel.h | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 144b615..8645181 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -41,6 +41,16 @@ extern const char linux_proc_banner[];
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
+/**
+ * upper_32_bits - return bits 32-63 of a number
+ * @n: the number we're accessing
+ *
+ * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
+ * the "right shift count >= width of type" warning when that quantity is
+ * 32-bits.
+ */
+#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
+
#define KERN_EMERG "<0>" /* system is unusable
*/
#define KERN_ALERT "<1>" /* action must be taken immediately
*/
#define KERN_CRIT "<2>" /* critical conditions
*/
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
