From: Pavel Machek <pavel@suse.cz>
To: kernel list <linux-kernel@vger.kernel.org>
Subject: better asm-generic/bitops.h
Date: Fri, 10 Nov 2000 23:21:48 +0100 [thread overview]
Message-ID: <20001110232148.A591@bug.ucw.cz> (raw)
Hi!
It might be usefull to someone..
Pavel
Index: bitops.h
===================================================================
RCS file: /home/cvs/Repository/linux/include/asm-generic/bitops.h,v
retrieving revision 1.1.1.1
diff -u -r1.1.1.1 bitops.h
--- bitops.h 2000/09/04 16:50:34 1.1.1.1
+++ bitops.h 2000/11/09 13:23:02
@@ -1,5 +1,6 @@
#ifndef _ASM_GENERIC_BITOPS_H_
#define _ASM_GENERIC_BITOPS_H_
+#include <asm/system.h>
/*
* For the benefit of those who are trying to port Linux to another
@@ -13,43 +14,120 @@
* You will have to change this if you are trying to port Linux to the
* Alpha architecture or to a Cray. :-)
*
- * C language equivalents written by Theodore Ts'o, 9/26/92
+ * C language equivalents written by Theodore Ts'o, 9/26/92
*/
-extern __inline__ int set_bit(int nr,int * addr)
+extern __inline__ int set_bit(int nr, void * a)
{
int mask, retval;
+ int *addr = a;
+ unsigned long flags;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
- cli();
+ save_flags(flags); cli();
retval = (mask & *addr) != 0;
*addr |= mask;
- sti();
+ restore_flags(flags);
return retval;
}
-extern __inline__ int clear_bit(int nr, int * addr)
+extern __inline__ int clear_bit(int nr, void * a)
{
int mask, retval;
+ int *addr = a;
+ unsigned long flags;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
- cli();
+ save_flags(flags); cli();
retval = (mask & *addr) != 0;
*addr &= ~mask;
- sti();
+ restore_flags(flags);
return retval;
}
-extern __inline__ int test_bit(int nr, int * addr)
+extern __inline__ int change_bit(int nr, void * a)
{
+ int mask, retval;
+ int *addr = a;
+ unsigned long flags;
+
+ addr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ save_flags(flags); cli();
+ retval = (mask & *addr) != 0;
+ *addr ^= mask;
+ restore_flags(flags);
+ return retval;
+}
+
+#define test_and_set_bit set_bit
+#define test_and_clear_bit clear_bit
+#define test_and_change_bit change_bit
+
+extern __inline__ int test_bit(int nr, void * a)
+{
int mask;
+ int *addr = a;
addr += nr >> 5;
mask = 1 << (nr & 0x1f);
return ((mask & *addr) != 0);
}
+
+
+/*
+ * ffz = Find First Zero in word. Undefined if no zero exists,
+ * so code should check against ~0UL first..
+ */
+extern __inline__ unsigned long ffz(unsigned long word)
+{
+ int i;
+ for (i=0; i<64; i++)
+ if (!(word & (1<<i)))
+ return i;
+ return -1;
+}
+
+extern __inline__ int find_next_zero_bit(void *addr, int size, int offset)
+{
+ unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
+ unsigned long result = offset & ~31UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if (offset) {
+ tmp = *(p++);
+ tmp |= ~0UL >> (32-offset);
+ if (size < 32)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size & ~31UL) {
+ if (~(tmp = *(p++)))
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp |= ~0UL << size;
+found_middle:
+ return result + ffz(tmp);
+}
+
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
#ifdef __KERNEL__
----- End forwarded message -----
--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/
reply other threads:[~2000-11-10 21:25 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20001110232148.A591@bug.ucw.cz \
--to=pavel@suse.cz \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).