Revision 3ad33b2436b545cbe8b28e53f3710432cad457ab authored by Lee Schermerhorn on 15 November 2007, 00:59:10 UTC, committed by Linus Torvalds on 15 November 2007, 02:45:38 UTC
We hit the BUG_ON() in mm/rmap.c:vma_address() when trying to migrate via
mbind(MPOL_MF_MOVE) a non-anon region that spans multiple vmas.  For
anon-regions, we just fail to migrate any pages beyond the 1st vma in the
range.

This occurs because do_mbind() collects a list of pages to migrate by
calling check_range().  check_range() walks the task's mm, spanning vmas as
necessary, to collect the migratable pages into a list.  Then, do_mbind()
calls migrate_pages() passing the list of pages, a function to allocate new
pages based on vma policy [new_vma_page()], and a pointer to the first vma
of the range.

For each page in the list, new_vma_page() calls page_address_in_vma()
passing the page and the vma [first in range] to obtain the address to get
for alloc_page_vma().  The page address is needed to get interleaving
policy correct.  If the pages in the list come from multiple vmas,
eventually, new_page_address() will pass that page to page_address_in_vma()
with the incorrect vma.  For !PageAnon pages, this will result in a bug
check in rmap.c:vma_address().  For anon pages, vma_address() will just
return EFAULT and fail the migration.

This patch modifies new_vma_page() to check the return value from
page_address_in_vma().  If the return value is EFAULT, new_vma_page()
searchs forward via vm_next for the vma that maps the page--i.e., that does
not return EFAULT.  This assumes that the pages in the list handed to
migrate_pages() is in address order.  This is currently case.  The patch
documents this assumption in a new comment block for new_vma_page().

If new_vma_page() cannot locate the vma mapping the page in a forward
search in the mm, it will pass a NULL vma to alloc_page_vma().  This will
result in the allocation using the task policy, if any, else system default
policy.  This situation is unlikely, but the patch documents this behavior
with a comment.

Note, this patch results in restarting from the first vma in a multi-vma
range each time new_vma_page() is called.  If this is not acceptable, we
can make the vma argument a pointer, both in new_vma_page() and it's caller
unmap_and_move() so that the value held by the loop in migrate_pages()
always passes down the last vma in which a page was found.  This will
require changes to all new_page_t functions passed to migrate_pages().  Is
this necessary?

For this patch to work, we can't bug check in vma_address() for pages
outside the argument vma.  This patch removes the BUG_ON().  All other
callers [besides new_vma_page()] already check the return status.

Tested on x86_64, 4 node NUMA platform.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent e1a1c99
Raw File
bitops.h
#ifndef _S390_BITOPS_H
#define _S390_BITOPS_H

/*
 *  include/asm-s390/bitops.h
 *
 *  S390 version
 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Derived from "include/asm-i386/bitops.h"
 *    Copyright (C) 1992, Linus Torvalds
 *
 */

#ifdef __KERNEL__

#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif

#include <linux/compiler.h>

/*
 * 32 bit bitops format:
 * bit 0 is the LSB of *addr; bit 31 is the MSB of *addr;
 * bit 32 is the LSB of *(addr+4). That combined with the
 * big endian byte order on S390 give the following bit
 * order in memory:
 *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10 \
 *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
 * after that follows the next long with bit numbers
 *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
 *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
 * The reason for this bit ordering is the fact that
 * in the architecture independent code bits operations
 * of the form "flags |= (1 << bitnr)" are used INTERMIXED
 * with operation of the form "set_bit(bitnr, flags)".
 *
 * 64 bit bitops format:
 * bit 0 is the LSB of *addr; bit 63 is the MSB of *addr;
 * bit 64 is the LSB of *(addr+8). That combined with the
 * big endian byte order on S390 give the following bit
 * order in memory:
 *    3f 3e 3d 3c 3b 3a 39 38 37 36 35 34 33 32 31 30
 *    2f 2e 2d 2c 2b 2a 29 28 27 26 25 24 23 22 21 20
 *    1f 1e 1d 1c 1b 1a 19 18 17 16 15 14 13 12 11 10
 *    0f 0e 0d 0c 0b 0a 09 08 07 06 05 04 03 02 01 00
 * after that follows the next long with bit numbers
 *    7f 7e 7d 7c 7b 7a 79 78 77 76 75 74 73 72 71 70
 *    6f 6e 6d 6c 6b 6a 69 68 67 66 65 64 63 62 61 60
 *    5f 5e 5d 5c 5b 5a 59 58 57 56 55 54 53 52 51 50
 *    4f 4e 4d 4c 4b 4a 49 48 47 46 45 44 43 42 41 40
 * The reason for this bit ordering is the fact that
 * in the architecture independent code bits operations
 * of the form "flags |= (1 << bitnr)" are used INTERMIXED
 * with operation of the form "set_bit(bitnr, flags)".
 */

/* bitmap tables from arch/S390/kernel/bitmap.S */
extern const char _oi_bitmap[];
extern const char _ni_bitmap[];
extern const char _zb_findmap[];
extern const char _sb_findmap[];

#ifndef __s390x__

#define __BITOPS_ALIGN		3
#define __BITOPS_WORDSIZE	32
#define __BITOPS_OR		"or"
#define __BITOPS_AND		"nr"
#define __BITOPS_XOR		"xr"

#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
	asm volatile(						\
		"	l	%0,%2\n"			\
		"0:	lr	%1,%0\n"			\
		__op_string "	%1,%3\n"			\
		"	cs	%0,%1,%2\n"			\
		"	jl	0b"				\
		: "=&d" (__old), "=&d" (__new),			\
		  "=Q" (*(unsigned long *) __addr)		\
		: "d" (__val), "Q" (*(unsigned long *) __addr)	\
		: "cc");

#else /* __GNUC__ */

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
	asm volatile(						\
		"	l	%0,0(%4)\n"			\
		"0:	lr	%1,%0\n"			\
		__op_string "	%1,%3\n"			\
		"	cs	%0,%1,0(%4)\n"			\
		"	jl	0b"				\
		: "=&d" (__old), "=&d" (__new),			\
		  "=m" (*(unsigned long *) __addr)		\
		: "d" (__val), "a" (__addr),			\
		  "m" (*(unsigned long *) __addr) : "cc");

#endif /* __GNUC__ */

#else /* __s390x__ */

#define __BITOPS_ALIGN		7
#define __BITOPS_WORDSIZE	64
#define __BITOPS_OR		"ogr"
#define __BITOPS_AND		"ngr"
#define __BITOPS_XOR		"xgr"

#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
	asm volatile(						\
		"	lg	%0,%2\n"			\
		"0:	lgr	%1,%0\n"			\
		__op_string "	%1,%3\n"			\
		"	csg	%0,%1,%2\n"			\
		"	jl	0b"				\
		: "=&d" (__old), "=&d" (__new),			\
		  "=Q" (*(unsigned long *) __addr)		\
		: "d" (__val), "Q" (*(unsigned long *) __addr)	\
		: "cc");

#else /* __GNUC__ */

#define __BITOPS_LOOP(__old, __new, __addr, __val, __op_string)	\
	asm volatile(						\
		"	lg	%0,0(%4)\n"			\
		"0:	lgr	%1,%0\n"			\
		__op_string "	%1,%3\n"			\
		"	csg	%0,%1,0(%4)\n"			\
		"	jl	0b"				\
		: "=&d" (__old), "=&d" (__new),			\
		  "=m" (*(unsigned long *) __addr)		\
		: "d" (__val), "a" (__addr),			\
		  "m" (*(unsigned long *) __addr) : "cc");


#endif /* __GNUC__ */

#endif /* __s390x__ */

#define __BITOPS_WORDS(bits) (((bits)+__BITOPS_WORDSIZE-1)/__BITOPS_WORDSIZE)
#define __BITOPS_BARRIER() asm volatile("" : : : "memory")

#ifdef CONFIG_SMP
/*
 * SMP safe set_bit routine based on compare and swap (CS)
 */
static inline void set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make OR mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
}

/*
 * SMP safe clear_bit routine based on compare and swap (CS)
 */
static inline void clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make AND mask */
	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
}

/*
 * SMP safe change_bit routine based on compare and swap (CS)
 */
static inline void change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make XOR mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
}

/*
 * SMP safe test_and_set_bit routine based on compare and swap (CS)
 */
static inline int
test_and_set_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make OR/test mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_OR);
	__BITOPS_BARRIER();
	return (old & mask) != 0;
}

/*
 * SMP safe test_and_clear_bit routine based on compare and swap (CS)
 */
static inline int
test_and_clear_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make AND/test mask */
	mask = ~(1UL << (nr & (__BITOPS_WORDSIZE - 1)));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_AND);
	__BITOPS_BARRIER();
	return (old ^ new) != 0;
}

/*
 * SMP safe test_and_change_bit routine based on compare and swap (CS) 
 */
static inline int
test_and_change_bit_cs(unsigned long nr, volatile unsigned long *ptr)
{
        unsigned long addr, old, new, mask;

	addr = (unsigned long) ptr;
	/* calculate address for CS */
	addr += (nr ^ (nr & (__BITOPS_WORDSIZE - 1))) >> 3;
	/* make XOR/test mask */
	mask = 1UL << (nr & (__BITOPS_WORDSIZE - 1));
	/* Do the atomic update. */
	__BITOPS_LOOP(old, new, addr, mask, __BITOPS_XOR);
	__BITOPS_BARRIER();
	return (old & mask) != 0;
}
#endif /* CONFIG_SMP */

/*
 * fast, non-SMP set_bit routine
 */
static inline void __set_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	asm volatile(
		"	oc	0(1,%1),0(%2)"
		: "=m" (*(char *) addr) : "a" (addr),
		  "a" (_oi_bitmap + (nr & 7)), "m" (*(char *) addr) : "cc" );
}

static inline void 
__constant_set_bit(const unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	*(unsigned char *) addr |= 1 << (nr & 7);
}

#define set_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_set_bit((nr),(addr)) : \
 __set_bit((nr),(addr)) )

/*
 * fast, non-SMP clear_bit routine
 */
static inline void 
__clear_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	asm volatile(
		"	nc	0(1,%1),0(%2)"
		: "=m" (*(char *) addr)	: "a" (addr),
		  "a" (_ni_bitmap + (nr & 7)), "m" (*(char *) addr) : "cc");
}

static inline void 
__constant_clear_bit(const unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	*(unsigned char *) addr &= ~(1 << (nr & 7));
}

#define clear_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_clear_bit((nr),(addr)) : \
 __clear_bit((nr),(addr)) )

/* 
 * fast, non-SMP change_bit routine 
 */
static inline void __change_bit(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	asm volatile(
		"	xc	0(1,%1),0(%2)"
		:  "=m" (*(char *) addr) : "a" (addr),
		   "a" (_oi_bitmap + (nr & 7)), "m" (*(char *) addr) : "cc" );
}

static inline void 
__constant_change_bit(const unsigned long nr, volatile unsigned long *ptr) 
{
	unsigned long addr;

	addr = ((unsigned long) ptr) + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	*(unsigned char *) addr ^= 1 << (nr & 7);
}

#define change_bit_simple(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_change_bit((nr),(addr)) : \
 __change_bit((nr),(addr)) )

/*
 * fast, non-SMP test_and_set_bit routine
 */
static inline int
test_and_set_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
	asm volatile(
		"	oc	0(1,%1),0(%2)"
		: "=m" (*(char *) addr)
		: "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		  "m" (*(char *) addr) : "cc", "memory");
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_set_bit(X,Y)		test_and_set_bit_simple(X,Y)

/*
 * fast, non-SMP test_and_clear_bit routine
 */
static inline int
test_and_clear_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
	asm volatile(
		"	nc	0(1,%1),0(%2)"
		: "=m" (*(char *) addr)
		: "a" (addr), "a" (_ni_bitmap + (nr & 7)),
		  "m" (*(char *) addr) : "cc", "memory");
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_clear_bit(X,Y)	test_and_clear_bit_simple(X,Y)

/*
 * fast, non-SMP test_and_change_bit routine
 */
static inline int
test_and_change_bit_simple(unsigned long nr, volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(unsigned char *) addr;
	asm volatile(
		"	xc	0(1,%1),0(%2)"
		: "=m" (*(char *) addr)
		: "a" (addr), "a" (_oi_bitmap + (nr & 7)),
		  "m" (*(char *) addr) : "cc", "memory");
	return (ch >> (nr & 7)) & 1;
}
#define __test_and_change_bit(X,Y)	test_and_change_bit_simple(X,Y)

#ifdef CONFIG_SMP
#define set_bit             set_bit_cs
#define clear_bit           clear_bit_cs
#define change_bit          change_bit_cs
#define test_and_set_bit    test_and_set_bit_cs
#define test_and_clear_bit  test_and_clear_bit_cs
#define test_and_change_bit test_and_change_bit_cs
#else
#define set_bit             set_bit_simple
#define clear_bit           clear_bit_simple
#define change_bit          change_bit_simple
#define test_and_set_bit    test_and_set_bit_simple
#define test_and_clear_bit  test_and_clear_bit_simple
#define test_and_change_bit test_and_change_bit_simple
#endif


/*
 * This routine doesn't need to be atomic.
 */

static inline int __test_bit(unsigned long nr, const volatile unsigned long *ptr)
{
	unsigned long addr;
	unsigned char ch;

	addr = (unsigned long) ptr + ((nr ^ (__BITOPS_WORDSIZE - 8)) >> 3);
	ch = *(volatile unsigned char *) addr;
	return (ch >> (nr & 7)) & 1;
}

static inline int 
__constant_test_bit(unsigned long nr, const volatile unsigned long *addr) {
    return (((volatile char *) addr)
	    [(nr^(__BITOPS_WORDSIZE-8))>>3] & (1<<(nr&7))) != 0;
}

#define test_bit(nr,addr) \
(__builtin_constant_p((nr)) ? \
 __constant_test_bit((nr),(addr)) : \
 __test_bit((nr),(addr)) )

/*
 * ffz = Find First Zero in word. Undefined if no zero exists,
 * so code should check against ~0UL first..
 */
static inline unsigned long ffz(unsigned long word)
{
        unsigned long bit = 0;

#ifdef __s390x__
	if (likely((word & 0xffffffff) == 0xffffffff)) {
		word >>= 32;
		bit += 32;
	}
#endif
	if (likely((word & 0xffff) == 0xffff)) {
		word >>= 16;
		bit += 16;
	}
	if (likely((word & 0xff) == 0xff)) {
		word >>= 8;
		bit += 8;
	}
	return bit + _zb_findmap[word & 0xff];
}

/*
 * __ffs = find first bit in word. Undefined if no bit exists,
 * so code should check against 0UL first..
 */
static inline unsigned long __ffs (unsigned long word)
{
	unsigned long bit = 0;

#ifdef __s390x__
	if (likely((word & 0xffffffff) == 0)) {
		word >>= 32;
		bit += 32;
	}
#endif
	if (likely((word & 0xffff) == 0)) {
		word >>= 16;
		bit += 16;
	}
	if (likely((word & 0xff) == 0)) {
		word >>= 8;
		bit += 8;
	}
	return bit + _sb_findmap[word & 0xff];
}

/*
 * Find-bit routines..
 */

#ifndef __s390x__

static inline int
find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
	asm volatile(
		"	lhi	%1,-1\n"
		"	lr	%2,%3\n"
		"	slr	%0,%0\n"
		"	ahi	%2,31\n"
		"	srl	%2,5\n"
		"0:	c	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	la	%0,4(%0)\n"
		"	brct	%2,0b\n"
		"	lr	%0,%3\n"
		"	j	4f\n"
		"1:	l	%2,0(%0,%4)\n"
		"	sll	%0,3\n"
		"	lhi	%1,0xff\n"
		"	tml	%2,0xffff\n"
		"	jno	2f\n"
		"	ahi	%0,16\n"
		"	srl	%2,16\n"
		"2:	tml	%2,0x00ff\n"
		"	jno	3f\n"
		"	ahi	%0,8\n"
		"	srl	%2,8\n"
		"3:	nr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	alr	%0,%2\n"
		"4:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) addr) : "cc");
        return (res < size) ? res : size;
}

static inline int
find_first_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
	asm volatile(
		"	slr	%1,%1\n"
		"	lr	%2,%3\n"
		"	slr	%0,%0\n"
		"	ahi	%2,31\n"
		"	srl	%2,5\n"
		"0:	c	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	la	%0,4(%0)\n"
		"	brct	%2,0b\n"
		"	lr	%0,%3\n"
		"	j	4f\n"
		"1:	l	%2,0(%0,%4)\n"
		"	sll	%0,3\n"
		"	lhi	%1,0xff\n"
		"	tml	%2,0xffff\n"
		"	jnz	2f\n"
		"	ahi	%0,16\n"
		"	srl	%2,16\n"
		"2:	tml	%2,0x00ff\n"
		"	jnz	3f\n"
		"	ahi	%0,8\n"
		"	srl	%2,8\n"
		"3:	nr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	alr	%0,%2\n"
		"4:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_sb_findmap),
		  "m" (*(addrtype *) addr) : "cc");
        return (res < size) ? res : size;
}

#else /* __s390x__ */

static inline unsigned long
find_first_zero_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
	asm volatile(
		"	lghi	%1,-1\n"
		"	lgr	%2,%3\n"
		"	slgr	%0,%0\n"
		"	aghi	%2,63\n"
		"	srlg	%2,%2,6\n"
		"0:	cg	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	la	%0,8(%0)\n"
		"	brct	%2,0b\n"
		"	lgr	%0,%3\n"
		"	j	5f\n"
		"1:	lg	%2,0(%0,%4)\n"
		"	sllg	%0,%0,3\n"
		"	clr	%2,%1\n"
		"	jne	2f\n"
		"	aghi	%0,32\n"
		"	srlg	%2,%2,32\n"
		"2:	lghi	%1,0xff\n"
		"	tmll	%2,0xffff\n"
		"	jno	3f\n"
		"	aghi	%0,16\n"
		"	srl	%2,16\n"
		"3:	tmll	%2,0x00ff\n"
		"	jno	4f\n"
		"	aghi	%0,8\n"
		"	srl	%2,8\n"
		"4:	ngr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	algr	%0,%2\n"
		"5:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) addr) : "cc");
        return (res < size) ? res : size;
}

static inline unsigned long
find_first_bit(const unsigned long * addr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
	asm volatile(
		"	slgr	%1,%1\n"
		"	lgr	%2,%3\n"
		"	slgr	%0,%0\n"
		"	aghi	%2,63\n"
		"	srlg	%2,%2,6\n"
		"0:	cg	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	aghi	%0,8\n"
		"	brct	%2,0b\n"
		"	lgr	%0,%3\n"
		"	j	5f\n"
		"1:	lg	%2,0(%0,%4)\n"
		"	sllg	%0,%0,3\n"
		"	clr	%2,%1\n"
		"	jne	2f\n"
		"	aghi	%0,32\n"
		"	srlg	%2,%2,32\n"
		"2:	lghi	%1,0xff\n"
		"	tmll	%2,0xffff\n"
		"	jnz	3f\n"
		"	aghi	%0,16\n"
		"	srl	%2,16\n"
		"3:	tmll	%2,0x00ff\n"
		"	jnz	4f\n"
		"	aghi	%0,8\n"
		"	srl	%2,8\n"
		"4:	ngr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	algr	%0,%2\n"
		"5:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (addr), "a" (&_sb_findmap),
		  "m" (*(addrtype *) addr) : "cc");
        return (res < size) ? res : size;
}

#endif /* __s390x__ */

static inline int
find_next_zero_bit (const unsigned long * addr, unsigned long size,
		    unsigned long offset)
{
        const unsigned long *p;
	unsigned long bit, set;

	if (offset >= size)
		return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
	if (bit) {
		/*
		 * s390 version of ffz returns __BITOPS_WORDSIZE
		 * if no zero bit is present in the word.
		 */
		set = ffz(*p >> bit) + bit;
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
	}
	return offset + find_first_zero_bit(p, size);
}

static inline int
find_next_bit (const unsigned long * addr, unsigned long size,
	       unsigned long offset)
{
        const unsigned long *p;
	unsigned long bit, set;

	if (offset >= size)
		return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
	if (bit) {
		/*
		 * s390 version of __ffs returns __BITOPS_WORDSIZE
		 * if no one bit is present in the word.
		 */
		set = __ffs(*p & (~0UL << bit));
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
	}
	return offset + find_first_bit(p, size);
}

/*
 * Every architecture must define this function. It's the fastest
 * way of searching a 140-bit bitmap where the first 100 bits are
 * unlikely to be set. It's guaranteed that at least one of the 140
 * bits is cleared.
 */
static inline int sched_find_first_bit(unsigned long *b)
{
	return find_first_bit(b, 140);
}

#include <asm-generic/bitops/ffs.h>

#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/fls64.h>

#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/lock.h>

/*
 * ATTENTION: intel byte ordering convention for ext2 and minix !!
 * bit 0 is the LSB of addr; bit 31 is the MSB of addr;
 * bit 32 is the LSB of (addr+4).
 * That combined with the little endian byte order of Intel gives the
 * following bit order in memory:
 *    07 06 05 04 03 02 01 00 15 14 13 12 11 10 09 08 \
 *    23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24
 */

#define ext2_set_bit(nr, addr)       \
	__test_and_set_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_set_bit_atomic(lock, nr, addr)       \
	test_and_set_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_clear_bit(nr, addr)     \
	__test_and_clear_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_clear_bit_atomic(lock, nr, addr)     \
	test_and_clear_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)
#define ext2_test_bit(nr, addr)      \
	test_bit((nr)^(__BITOPS_WORDSIZE - 8), (unsigned long *)addr)

#ifndef __s390x__

static inline int 
ext2_find_first_zero_bit(void *vaddr, unsigned int size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
	unsigned long cmp, count;
        unsigned int res;

        if (!size)
                return 0;
	asm volatile(
		"	lhi	%1,-1\n"
		"	lr	%2,%3\n"
		"	ahi	%2,31\n"
		"	srl	%2,5\n"
		"	slr	%0,%0\n"
		"0:	cl	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	ahi	%0,4\n"
		"	brct	%2,0b\n"
		"	lr	%0,%3\n"
		"	j	4f\n"
		"1:	l	%2,0(%0,%4)\n"
		"	sll	%0,3\n"
		"	ahi	%0,24\n"
		"	lhi	%1,0xff\n"
		"	tmh	%2,0xffff\n"
		"	jo	2f\n"
		"	ahi	%0,-16\n"
		"	srl	%2,16\n"
		"2:	tml	%2,0xff00\n"
		"	jo	3f\n"
		"	ahi	%0,-8\n"
		"	srl	%2,8\n"
		"3:	nr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	alr	%0,%2\n"
		"4:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (vaddr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) vaddr) : "cc");
        return (res < size) ? res : size;
}

#else /* __s390x__ */

static inline unsigned long
ext2_find_first_zero_bit(void *vaddr, unsigned long size)
{
	typedef struct { long _[__BITOPS_WORDS(size)]; } addrtype;
        unsigned long res, cmp, count;

        if (!size)
                return 0;
	asm volatile(
		"	lghi	%1,-1\n"
		"	lgr	%2,%3\n"
		"	aghi	%2,63\n"
		"	srlg	%2,%2,6\n"
		"	slgr	%0,%0\n"
		"0:	clg	%1,0(%0,%4)\n"
		"	jne	1f\n"
		"	aghi	%0,8\n"
		"	brct	%2,0b\n"
		"	lgr	%0,%3\n"
		"	j	5f\n"
		"1:	cl	%1,0(%0,%4)\n"
		"	jne	2f\n"
		"	aghi	%0,4\n"
		"2:	l	%2,0(%0,%4)\n"
		"	sllg	%0,%0,3\n"
		"	aghi	%0,24\n"
		"	lghi	%1,0xff\n"
		"	tmlh	%2,0xffff\n"
		"	jo	3f\n"
		"	aghi	%0,-16\n"
		"	srl	%2,16\n"
		"3:	tmll	%2,0xff00\n"
		"	jo	4f\n"
		"	aghi	%0,-8\n"
		"	srl	%2,8\n"
		"4:	ngr	%2,%1\n"
		"	ic	%2,0(%2,%5)\n"
		"	algr	%0,%2\n"
		"5:"
		: "=&a" (res), "=&d" (cmp), "=&a" (count)
		: "a" (size), "a" (vaddr), "a" (&_zb_findmap),
		  "m" (*(addrtype *) vaddr) : "cc");
        return (res < size) ? res : size;
}

#endif /* __s390x__ */

static inline int
ext2_find_next_zero_bit(void *vaddr, unsigned long size, unsigned long offset)
{
        unsigned long *addr = vaddr, *p;
	unsigned long word, bit, set;

        if (offset >= size)
                return size;
	bit = offset & (__BITOPS_WORDSIZE - 1);
	offset -= bit;
	size -= offset;
	p = addr + offset / __BITOPS_WORDSIZE;
        if (bit) {
#ifndef __s390x__
		asm volatile(
			"	ic	%0,0(%1)\n"
			"	icm	%0,2,1(%1)\n"
			"	icm	%0,4,2(%1)\n"
			"	icm	%0,8,3(%1)"
			: "=&a" (word) : "a" (p), "m" (*p) : "cc");
#else
		asm volatile(
			"	lrvg	%0,%1"
			: "=a" (word) : "m" (*p) );
#endif
		/*
		 * s390 version of ffz returns __BITOPS_WORDSIZE
		 * if no zero bit is present in the word.
		 */
		set = ffz(word >> bit) + bit;
		if (set >= size)
			return size + offset;
		if (set < __BITOPS_WORDSIZE)
			return set + offset;
		offset += __BITOPS_WORDSIZE;
		size -= __BITOPS_WORDSIZE;
		p++;
        }
	return offset + ext2_find_first_zero_bit(p, size);
}

#include <asm-generic/bitops/minix.h>

#endif /* __KERNEL__ */

#endif /* _S390_BITOPS_H */
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