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