convert ill defined log2() to ilog2()
It's *wrong* to have
#define log2(n) ffz(~(n))
It should be *reversed*:
#define log2(n) flz(~(n))
or
#define log2(n) fls(n)
or just use
ilog2(n) defined in linux/log2.h.
This patch follows the last solution, recommended by Andrew Morton.
Cc: <linux-ext4@vger.kernel.org>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Chris Ahna <christopher.j.ahna@intel.com>
Cc: David Mosberger-Tang <davidm@hpl.hp.com>
Cc: Kyle McMartin <kyle@parisc-linux.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/agp/i460-agp.c b/drivers/char/agp/i460-agp.c
index 70117df..e72a83e 100644
--- a/drivers/char/agp/i460-agp.c
+++ b/drivers/char/agp/i460-agp.c
@@ -13,6 +13,7 @@
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/agp_backend.h>
+#include <linux/log2.h>
#include "agp.h"
@@ -59,8 +60,6 @@
*/
#define WR_FLUSH_GATT(index) RD_GATT(index)
-#define log2(x) ffz(~(x))
-
static struct {
void *gatt; /* ioremap'd GATT area */
@@ -148,7 +147,7 @@
* values[i].size.
*/
values[i].num_entries = (values[i].size << 8) >> (I460_IO_PAGE_SHIFT - 12);
- values[i].page_order = log2((sizeof(u32)*values[i].num_entries) >> PAGE_SHIFT);
+ values[i].page_order = ilog2((sizeof(u32)*values[i].num_entries) >> PAGE_SHIFT);
}
for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {