[PATCH] s390: fix ext2_find_next_bit

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



(oops, left off the s390 list on the first send)

The following changes get ext4 on s390 up and running for me.

the switch from ffs to __ffs changes where we start counting
(if the first bit is set, is that "0" or "1?"  ext2 wants to 
start counting with "0") and the rest is, honestly, just lifted 
from the stock find_next_bit() implementation.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
--

Index: linux-2.6/arch/s390/include/asm/bitops.h
===================================================================
--- linux-2.6.orig/arch/s390/include/asm/bitops.h	2008-08-11 16:23:58.000000000 -0500
+++ linux-2.6/arch/s390/include/asm/bitops.h	2008-08-21 00:49:40.950176518 -0500
@@ -862,10 +862,10 @@ static inline int ext2_find_next_bit(voi
 	p = addr + offset / __BITOPS_WORDSIZE;
 	if (bit) {
 		/*
-		 * s390 version of ffz returns __BITOPS_WORDSIZE
-		 * if no zero bit is present in the word.
+		 * s390 version of ffs returns __BITOPS_WORDSIZE
+		 * if no set bit is present in the word.
 		 */
-		set = ffs(__load_ulong_le(p, 0) >> bit) + bit;
+		set = __ffs(__load_ulong_le(p, 0) & (~0UL << bit));
 		if (set >= size)
 			return size + offset;
 		if (set < __BITOPS_WORDSIZE)



--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Reiser Filesystem Development]     [Ceph FS]     [Kernel Newbies]     [Security]     [Netfilter]     [Bugtraq]     [Linux FS]     [Yosemite National Park]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]     [Linux Media]

  Powered by Linux