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-rw-r--r--include/asm-i386/Kbuild1
-rw-r--r--include/asm-i386/dma-mapping.h9
-rw-r--r--include/asm-i386/fixmap.h7
-rw-r--r--include/asm-i386/mmzone.h6
-rw-r--r--include/asm-i386/pgtable-2level.h3
-rw-r--r--include/asm-i386/pgtable-3level.h4
-rw-r--r--include/asm-i386/pgtable.h45
-rw-r--r--include/asm-i386/processor.h60
-rw-r--r--include/asm-i386/ptrace-abi.h39
-rw-r--r--include/asm-i386/ptrace.h35
-rw-r--r--include/asm-i386/sync_bitops.h156
-rw-r--r--include/asm-i386/system.h36
12 files changed, 302 insertions, 99 deletions
diff --git a/include/asm-i386/Kbuild b/include/asm-i386/Kbuild
index b75a348d0c1..147e4ac1ebf 100644
--- a/include/asm-i386/Kbuild
+++ b/include/asm-i386/Kbuild
@@ -3,6 +3,7 @@ include include/asm-generic/Kbuild.asm
header-y += boot.h
header-y += debugreg.h
header-y += ldt.h
+header-y += ptrace-abi.h
header-y += ucontext.h
unifdef-y += mtrr.h
diff --git a/include/asm-i386/dma-mapping.h b/include/asm-i386/dma-mapping.h
index 9cf20cacf76..576ae01d71c 100644
--- a/include/asm-i386/dma-mapping.h
+++ b/include/asm-i386/dma-mapping.h
@@ -21,8 +21,7 @@ static inline dma_addr_t
dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction)
{
- if (direction == DMA_NONE)
- BUG();
+ BUG_ON(direction == DMA_NONE);
WARN_ON(size == 0);
flush_write_buffers();
return virt_to_phys(ptr);
@@ -32,8 +31,7 @@ static inline void
dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction direction)
{
- if (direction == DMA_NONE)
- BUG();
+ BUG_ON(direction == DMA_NONE);
}
static inline int
@@ -42,8 +40,7 @@ dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
{
int i;
- if (direction == DMA_NONE)
- BUG();
+ BUG_ON(direction == DMA_NONE);
WARN_ON(nents == 0 || sg[0].length == 0);
for (i = 0; i < nents; i++ ) {
diff --git a/include/asm-i386/fixmap.h b/include/asm-i386/fixmap.h
index a48cc3f7ccc..02428cb3662 100644
--- a/include/asm-i386/fixmap.h
+++ b/include/asm-i386/fixmap.h
@@ -19,7 +19,11 @@
* Leave one empty page between vmalloc'ed areas and
* the start of the fixmap.
*/
-#define __FIXADDR_TOP 0xfffff000
+#ifndef CONFIG_COMPAT_VDSO
+extern unsigned long __FIXADDR_TOP;
+#else
+#define __FIXADDR_TOP 0xfffff000
+#endif
#ifndef __ASSEMBLY__
#include <linux/kernel.h>
@@ -93,6 +97,7 @@ enum fixed_addresses {
extern void __set_fixmap (enum fixed_addresses idx,
unsigned long phys, pgprot_t flags);
+extern void reserve_top_address(unsigned long reserve);
#define set_fixmap(idx, phys) \
__set_fixmap(idx, phys, PAGE_KERNEL)
diff --git a/include/asm-i386/mmzone.h b/include/asm-i386/mmzone.h
index 22cb07cc8f3..61b07332200 100644
--- a/include/asm-i386/mmzone.h
+++ b/include/asm-i386/mmzone.h
@@ -38,10 +38,16 @@ static inline void get_memcfg_numa(void)
}
extern int early_pfn_to_nid(unsigned long pfn);
+extern void numa_kva_reserve(void);
#else /* !CONFIG_NUMA */
+
#define get_memcfg_numa get_memcfg_numa_flat
#define get_zholes_size(n) (0)
+
+static inline void numa_kva_reserve(void)
+{
+}
#endif /* CONFIG_NUMA */
#ifdef CONFIG_DISCONTIGMEM
diff --git a/include/asm-i386/pgtable-2level.h b/include/asm-i386/pgtable-2level.h
index 2756d4b04c2..201c86a6711 100644
--- a/include/asm-i386/pgtable-2level.h
+++ b/include/asm-i386/pgtable-2level.h
@@ -21,8 +21,9 @@
#define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
#define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define ptep_get_and_clear(mm,addr,xp) __pte(xchg(&(xp)->pte_low, 0))
-#define pte_same(a, b) ((a).pte_low == (b).pte_low)
+
#define pte_page(x) pfn_to_page(pte_pfn(x))
#define pte_none(x) (!(x).pte_low)
#define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
diff --git a/include/asm-i386/pgtable-3level.h b/include/asm-i386/pgtable-3level.h
index dccb1b3337a..0d899173232 100644
--- a/include/asm-i386/pgtable-3level.h
+++ b/include/asm-i386/pgtable-3level.h
@@ -77,7 +77,7 @@ static inline void pud_clear (pud_t * pud) { }
#define pud_page(pud) \
((struct page *) __va(pud_val(pud) & PAGE_MASK))
-#define pud_page_kernel(pud) \
+#define pud_page_vaddr(pud) \
((unsigned long) __va(pud_val(pud) & PAGE_MASK))
@@ -105,6 +105,7 @@ static inline void pmd_clear(pmd_t *pmd)
*(tmp + 1) = 0;
}
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t res;
@@ -117,6 +118,7 @@ static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
return res;
}
+#define __HAVE_ARCH_PTE_SAME
static inline int pte_same(pte_t a, pte_t b)
{
return a.pte_low == b.pte_low && a.pte_high == b.pte_high;
diff --git a/include/asm-i386/pgtable.h b/include/asm-i386/pgtable.h
index 09697fec3d2..0dc051a8078 100644
--- a/include/asm-i386/pgtable.h
+++ b/include/asm-i386/pgtable.h
@@ -246,6 +246,23 @@ static inline pte_t pte_mkhuge(pte_t pte) { (pte).pte_low |= _PAGE_PSE; return p
# include <asm/pgtable-2level.h>
#endif
+/*
+ * We only update the dirty/accessed state if we set
+ * the dirty bit by hand in the kernel, since the hardware
+ * will do the accessed bit for us, and we don't want to
+ * race with other CPU's that might be updating the dirty
+ * bit at the same time.
+ */
+#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
+#define ptep_set_access_flags(vma, address, ptep, entry, dirty) \
+do { \
+ if (dirty) { \
+ (ptep)->pte_low = (entry).pte_low; \
+ flush_tlb_page(vma, address); \
+ } \
+} while (0)
+
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
static inline int ptep_test_and_clear_dirty(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
if (!pte_dirty(*ptep))
@@ -253,6 +270,7 @@ static inline int ptep_test_and_clear_dirty(struct vm_area_struct *vma, unsigned
return test_and_clear_bit(_PAGE_BIT_DIRTY, &ptep->pte_low);
}
+#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
if (!pte_young(*ptep))
@@ -260,6 +278,7 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned
return test_and_clear_bit(_PAGE_BIT_ACCESSED, &ptep->pte_low);
}
+#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, unsigned long addr, pte_t *ptep, int full)
{
pte_t pte;
@@ -272,6 +291,7 @@ static inline pte_t ptep_get_and_clear_full(struct mm_struct *mm, unsigned long
return pte;
}
+#define __HAVE_ARCH_PTEP_SET_WRPROTECT
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
clear_bit(_PAGE_BIT_RW, &ptep->pte_low);
@@ -364,11 +384,11 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
#define pte_index(address) \
(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset_kernel(dir, address) \
- ((pte_t *) pmd_page_kernel(*(dir)) + pte_index(address))
+ ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
#define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
-#define pmd_page_kernel(pmd) \
+#define pmd_page_vaddr(pmd) \
((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
/*
@@ -411,23 +431,8 @@ extern void noexec_setup(const char *str);
/*
* The i386 doesn't have any external MMU info: the kernel page
* tables contain all the necessary information.
- *
- * Also, we only update the dirty/accessed state if we set
- * the dirty bit by hand in the kernel, since the hardware
- * will do the accessed bit for us, and we don't want to
- * race with other CPU's that might be updating the dirty
- * bit at the same time.
*/
#define update_mmu_cache(vma,address,pte) do { } while (0)
-#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
-#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
- do { \
- if (__dirty) { \
- (__ptep)->pte_low = (__entry).pte_low; \
- flush_tlb_page(__vma, __address); \
- } \
- } while (0)
-
#endif /* !__ASSEMBLY__ */
#ifdef CONFIG_FLATMEM
@@ -441,12 +446,6 @@ extern void noexec_setup(const char *str);
#define GET_IOSPACE(pfn) 0
#define GET_PFN(pfn) (pfn)
-#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
-#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
-#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
-#define __HAVE_ARCH_PTEP_GET_AND_CLEAR_FULL
-#define __HAVE_ARCH_PTEP_SET_WRPROTECT
-#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>
#endif /* _I386_PGTABLE_H */
diff --git a/include/asm-i386/processor.h b/include/asm-i386/processor.h
index b32346d62e1..2277127696d 100644
--- a/include/asm-i386/processor.h
+++ b/include/asm-i386/processor.h
@@ -143,6 +143,18 @@ static inline void detect_ht(struct cpuinfo_x86 *c) {}
#define X86_EFLAGS_VIP 0x00100000 /* Virtual Interrupt Pending */
#define X86_EFLAGS_ID 0x00200000 /* CPUID detection flag */
+static inline void __cpuid(unsigned int *eax, unsigned int *ebx,
+ unsigned int *ecx, unsigned int *edx)
+{
+ /* ecx is often an input as well as an output. */
+ __asm__("cpuid"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx));
+}
+
/*
* Generic CPUID function
* clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
@@ -150,24 +162,18 @@ static inline void detect_ht(struct cpuinfo_x86 *c) {}
*/
static inline void cpuid(unsigned int op, unsigned int *eax, unsigned int *ebx, unsigned int *ecx, unsigned int *edx)
{
- __asm__("cpuid"
- : "=a" (*eax),
- "=b" (*ebx),
- "=c" (*ecx),
- "=d" (*edx)
- : "0" (op), "c"(0));
+ *eax = op;
+ *ecx = 0;
+ __cpuid(eax, ebx, ecx, edx);
}
/* Some CPUID calls want 'count' to be placed in ecx */
static inline void cpuid_count(int op, int count, int *eax, int *ebx, int *ecx,
- int *edx)
+ int *edx)
{
- __asm__("cpuid"
- : "=a" (*eax),
- "=b" (*ebx),
- "=c" (*ecx),
- "=d" (*edx)
- : "0" (op), "c" (count));
+ *eax = op;
+ *ecx = count;
+ __cpuid(eax, ebx, ecx, edx);
}
/*
@@ -175,42 +181,30 @@ static inline void cpuid_count(int op, int count, int *eax, int *ebx, int *ecx,
*/
static inline unsigned int cpuid_eax(unsigned int op)
{
- unsigned int eax;
+ unsigned int eax, ebx, ecx, edx;
- __asm__("cpuid"
- : "=a" (eax)
- : "0" (op)
- : "bx", "cx", "dx");
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return eax;
}
static inline unsigned int cpuid_ebx(unsigned int op)
{
- unsigned int eax, ebx;
+ unsigned int eax, ebx, ecx, edx;
- __asm__("cpuid"
- : "=a" (eax), "=b" (ebx)
- : "0" (op)
- : "cx", "dx" );
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return ebx;
}
static inline unsigned int cpuid_ecx(unsigned int op)
{
- unsigned int eax, ecx;
+ unsigned int eax, ebx, ecx, edx;
- __asm__("cpuid"
- : "=a" (eax), "=c" (ecx)
- : "0" (op)
- : "bx", "dx" );
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return ecx;
}
static inline unsigned int cpuid_edx(unsigned int op)
{
- unsigned int eax, edx;
+ unsigned int eax, ebx, ecx, edx;
- __asm__("cpuid"
- : "=a" (eax), "=d" (edx)
- : "0" (op)
- : "bx", "cx");
+ cpuid(op, &eax, &ebx, &ecx, &edx);
return edx;
}
diff --git a/include/asm-i386/ptrace-abi.h b/include/asm-i386/ptrace-abi.h
new file mode 100644
index 00000000000..a44901817a2
--- /dev/null
+++ b/include/asm-i386/ptrace-abi.h
@@ -0,0 +1,39 @@
+#ifndef I386_PTRACE_ABI_H
+#define I386_PTRACE_ABI_H
+
+#define EBX 0
+#define ECX 1
+#define EDX 2
+#define ESI 3
+#define EDI 4
+#define EBP 5
+#define EAX 6
+#define DS 7
+#define ES 8
+#define FS 9
+#define GS 10
+#define ORIG_EAX 11
+#define EIP 12
+#define CS 13
+#define EFL 14
+#define UESP 15
+#define SS 16
+#define FRAME_SIZE 17
+
+/* Arbitrarily choose the same ptrace numbers as used by the Sparc code. */
+#define PTRACE_GETREGS 12
+#define PTRACE_SETREGS 13
+#define PTRACE_GETFPREGS 14
+#define PTRACE_SETFPREGS 15
+#define PTRACE_GETFPXREGS 18
+#define PTRACE_SETFPXREGS 19
+
+#define PTRACE_OLDSETOPTIONS 21
+
+#define PTRACE_GET_THREAD_AREA 25
+#define PTRACE_SET_THREAD_AREA 26
+
+#define PTRACE_SYSEMU 31
+#define PTRACE_SYSEMU_SINGLESTEP 32
+
+#endif
diff --git a/include/asm-i386/ptrace.h b/include/asm-i386/ptrace.h
index f324c53b6f9..1910880fcd4 100644
--- a/include/asm-i386/ptrace.h
+++ b/include/asm-i386/ptrace.h
@@ -1,24 +1,7 @@
#ifndef _I386_PTRACE_H
#define _I386_PTRACE_H
-#define EBX 0
-#define ECX 1
-#define EDX 2
-#define ESI 3
-#define EDI 4
-#define EBP 5
-#define EAX 6
-#define DS 7
-#define ES 8
-#define FS 9
-#define GS 10
-#define ORIG_EAX 11
-#define EIP 12
-#define CS 13
-#define EFL 14
-#define UESP 15
-#define SS 16
-#define FRAME_SIZE 17
+#include <asm/ptrace-abi.h>
/* this struct defines the way the registers are stored on the
stack during a system call. */
@@ -41,22 +24,6 @@ struct pt_regs {
int xss;
};
-/* Arbitrarily choose the same ptrace numbers as used by the Sparc code. */
-#define PTRACE_GETREGS 12
-#define PTRACE_SETREGS 13
-#define PTRACE_GETFPREGS 14
-#define PTRACE_SETFPREGS 15
-#define PTRACE_GETFPXREGS 18
-#define PTRACE_SETFPXREGS 19
-
-#define PTRACE_OLDSETOPTIONS 21
-
-#define PTRACE_GET_THREAD_AREA 25
-#define PTRACE_SET_THREAD_AREA 26
-
-#define PTRACE_SYSEMU 31
-#define PTRACE_SYSEMU_SINGLESTEP 32
-
#ifdef __KERNEL__
#include <asm/vm86.h>
diff --git a/include/asm-i386/sync_bitops.h b/include/asm-i386/sync_bitops.h
new file mode 100644
index 00000000000..c94d51c993e
--- /dev/null
+++ b/include/asm-i386/sync_bitops.h
@@ -0,0 +1,156 @@
+#ifndef _I386_SYNC_BITOPS_H
+#define _I386_SYNC_BITOPS_H
+
+/*
+ * Copyright 1992, Linus Torvalds.
+ */
+
+/*
+ * These have to be done with inline assembly: that way the bit-setting
+ * is guaranteed to be atomic. All bit operations return 0 if the bit
+ * was cleared before the operation and != 0 if it was not.
+ *
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ */
+
+#define ADDR (*(volatile long *) addr)
+
+/**
+ * sync_set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered. See __set_bit()
+ * if you do not require the atomic guarantees.
+ *
+ * Note: there are no guarantees that this function will not be reordered
+ * on non x86 architectures, so if you are writting portable code,
+ * make sure not to rely on its reordering guarantees.
+ *
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void sync_set_bit(int nr, volatile unsigned long * addr)
+{
+ __asm__ __volatile__("lock; btsl %1,%0"
+ :"+m" (ADDR)
+ :"Ir" (nr)
+ : "memory");
+}
+
+/**
+ * sync_clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * sync_clear_bit() is atomic and may not be reordered. However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * in order to ensure changes are visible on other processors.
+ */
+static inline void sync_clear_bit(int nr, volatile unsigned long * addr)
+{
+ __asm__ __volatile__("lock; btrl %1,%0"
+ :"+m" (ADDR)
+ :"Ir" (nr)
+ : "memory");
+}
+
+/**
+ * sync_change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered. It may be
+ * reordered on other architectures than x86.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void sync_change_bit(int nr, volatile unsigned long * addr)
+{
+ __asm__ __volatile__("lock; btcl %1,%0"
+ :"+m" (ADDR)
+ :"Ir" (nr)
+ : "memory");
+}
+
+/**
+ * sync_test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It may be reordered on other architectures than x86.
+ * It also implies a memory barrier.
+ */
+static inline int sync_test_and_set_bit(int nr, volatile unsigned long * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__("lock; btsl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"+m" (ADDR)
+ :"Ir" (nr) : "memory");
+ return oldbit;
+}
+
+/**
+ * sync_test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It can be reorderdered on other architectures other than x86.
+ * It also implies a memory barrier.
+ */
+static inline int sync_test_and_clear_bit(int nr, volatile unsigned long * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__("lock; btrl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"+m" (ADDR)
+ :"Ir" (nr) : "memory");
+ return oldbit;
+}
+
+/**
+ * sync_test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int sync_test_and_change_bit(int nr, volatile unsigned long* addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__("lock; btcl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit),"+m" (ADDR)
+ :"Ir" (nr) : "memory");
+ return oldbit;
+}
+
+static __always_inline int sync_const_test_bit(int nr, const volatile unsigned long *addr)
+{
+ return ((1UL << (nr & 31)) &
+ (((const volatile unsigned int *)addr)[nr >> 5])) != 0;
+}
+
+static inline int sync_var_test_bit(int nr, const volatile unsigned long * addr)
+{
+ int oldbit;
+
+ __asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0"
+ :"=r" (oldbit)
+ :"m" (ADDR),"Ir" (nr));
+ return oldbit;
+}
+
+#define sync_test_bit(nr,addr) \
+ (__builtin_constant_p(nr) ? \
+ sync_constant_test_bit((nr),(addr)) : \
+ sync_var_test_bit((nr),(addr)))
+
+#undef ADDR
+
+#endif /* _I386_SYNC_BITOPS_H */
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h
index 098bcee94e3..a6dabbcd6e6 100644
--- a/include/asm-i386/system.h
+++ b/include/asm-i386/system.h
@@ -267,6 +267,9 @@ static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int siz
#define cmpxchg(ptr,o,n)\
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
(unsigned long)(n),sizeof(*(ptr))))
+#define sync_cmpxchg(ptr,o,n)\
+ ((__typeof__(*(ptr)))__sync_cmpxchg((ptr),(unsigned long)(o),\
+ (unsigned long)(n),sizeof(*(ptr))))
#endif
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
@@ -296,6 +299,39 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
return old;
}
+/*
+ * Always use locked operations when touching memory shared with a
+ * hypervisor, since the system may be SMP even if the guest kernel
+ * isn't.
+ */
+static inline unsigned long __sync_cmpxchg(volatile void *ptr,
+ unsigned long old,
+ unsigned long new, int size)
+{
+ unsigned long prev;
+ switch (size) {
+ case 1:
+ __asm__ __volatile__("lock; cmpxchgb %b1,%2"
+ : "=a"(prev)
+ : "q"(new), "m"(*__xg(ptr)), "0"(old)
+ : "memory");
+ return prev;
+ case 2:
+ __asm__ __volatile__("lock; cmpxchgw %w1,%2"
+ : "=a"(prev)
+ : "r"(new), "m"(*__xg(ptr)), "0"(old)
+ : "memory");
+ return prev;
+ case 4:
+ __asm__ __volatile__("lock; cmpxchgl %1,%2"
+ : "=a"(prev)
+ : "r"(new), "m"(*__xg(ptr)), "0"(old)
+ : "memory");
+ return prev;
+ }
+ return old;
+}
+
#ifndef CONFIG_X86_CMPXCHG
/*
* Building a kernel capable running on 80386. It may be necessary to