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-rw-r--r--arch/x86/include/asm/asm.h6
-rw-r--r--arch/x86/include/asm/atomic.h69
-rw-r--r--arch/x86/include/asm/atomic64_32.h81
-rw-r--r--arch/x86/include/asm/atomic64_64.h73
-rw-r--r--arch/x86/include/asm/bug.h4
-rw-r--r--arch/x86/include/asm/cmpxchg.h2
-rw-r--r--arch/x86/include/asm/entry_arch.h2
-rw-r--r--arch/x86/include/asm/hardirq.h1
-rw-r--r--arch/x86/include/asm/hw_irq.h2
-rw-r--r--arch/x86/include/asm/io.h4
-rw-r--r--arch/x86/include/asm/irq_vectors.h3
-rw-r--r--arch/x86/include/asm/kprobes.h8
-rw-r--r--arch/x86/include/asm/mmu_context.h2
-rw-r--r--arch/x86/include/asm/paravirt_types.h16
-rw-r--r--arch/x86/include/asm/processor.h2
-rw-r--r--arch/x86/include/asm/refcount.h109
16 files changed, 291 insertions, 93 deletions
diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 7a9df3beb89b..676ee5807d86 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -74,6 +74,9 @@
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
+# define _ASM_EXTABLE_REFCOUNT(from, to) \
+ _ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
+
# define _ASM_NOKPROBE(entry) \
.pushsection "_kprobe_blacklist","aw" ; \
_ASM_ALIGN ; \
@@ -123,6 +126,9 @@
# define _ASM_EXTABLE_EX(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_ext)
+# define _ASM_EXTABLE_REFCOUNT(from, to) \
+ _ASM_EXTABLE_HANDLE(from, to, ex_handler_refcount)
+
/* For C file, we already have NOKPROBE_SYMBOL macro */
#endif
diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h
index 33380b871463..0874ebda3069 100644
--- a/arch/x86/include/asm/atomic.h
+++ b/arch/x86/include/asm/atomic.h
@@ -197,35 +197,56 @@ static inline int atomic_xchg(atomic_t *v, int new)
return xchg(&v->counter, new);
}
-#define ATOMIC_OP(op) \
-static inline void atomic_##op(int i, atomic_t *v) \
-{ \
- asm volatile(LOCK_PREFIX #op"l %1,%0" \
- : "+m" (v->counter) \
- : "ir" (i) \
- : "memory"); \
+static inline void atomic_and(int i, atomic_t *v)
+{
+ asm volatile(LOCK_PREFIX "andl %1,%0"
+ : "+m" (v->counter)
+ : "ir" (i)
+ : "memory");
+}
+
+static inline int atomic_fetch_and(int i, atomic_t *v)
+{
+ int val = atomic_read(v);
+
+ do { } while (!atomic_try_cmpxchg(v, &val, val & i));
+
+ return val;
}
-#define ATOMIC_FETCH_OP(op, c_op) \
-static inline int atomic_fetch_##op(int i, atomic_t *v) \
-{ \
- int val = atomic_read(v); \
- do { \
- } while (!atomic_try_cmpxchg(v, &val, val c_op i)); \
- return val; \
+static inline void atomic_or(int i, atomic_t *v)
+{
+ asm volatile(LOCK_PREFIX "orl %1,%0"
+ : "+m" (v->counter)
+ : "ir" (i)
+ : "memory");
}
-#define ATOMIC_OPS(op, c_op) \
- ATOMIC_OP(op) \
- ATOMIC_FETCH_OP(op, c_op)
+static inline int atomic_fetch_or(int i, atomic_t *v)
+{
+ int val = atomic_read(v);
-ATOMIC_OPS(and, &)
-ATOMIC_OPS(or , |)
-ATOMIC_OPS(xor, ^)
+ do { } while (!atomic_try_cmpxchg(v, &val, val | i));
-#undef ATOMIC_OPS
-#undef ATOMIC_FETCH_OP
-#undef ATOMIC_OP
+ return val;
+}
+
+static inline void atomic_xor(int i, atomic_t *v)
+{
+ asm volatile(LOCK_PREFIX "xorl %1,%0"
+ : "+m" (v->counter)
+ : "ir" (i)
+ : "memory");
+}
+
+static inline int atomic_fetch_xor(int i, atomic_t *v)
+{
+ int val = atomic_read(v);
+
+ do { } while (!atomic_try_cmpxchg(v, &val, val ^ i));
+
+ return val;
+}
/**
* __atomic_add_unless - add unless the number is already a given value
@@ -239,10 +260,12 @@ ATOMIC_OPS(xor, ^)
static __always_inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c = atomic_read(v);
+
do {
if (unlikely(c == u))
break;
} while (!atomic_try_cmpxchg(v, &c, c + a));
+
return c;
}
diff --git a/arch/x86/include/asm/atomic64_32.h b/arch/x86/include/asm/atomic64_32.h
index 71d7705fb303..9e206f31ce2a 100644
--- a/arch/x86/include/asm/atomic64_32.h
+++ b/arch/x86/include/asm/atomic64_32.h
@@ -312,37 +312,70 @@ static inline long long atomic64_dec_if_positive(atomic64_t *v)
#undef alternative_atomic64
#undef __alternative_atomic64
-#define ATOMIC64_OP(op, c_op) \
-static inline void atomic64_##op(long long i, atomic64_t *v) \
-{ \
- long long old, c = 0; \
- while ((old = atomic64_cmpxchg(v, c, c c_op i)) != c) \
- c = old; \
+static inline void atomic64_and(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c & i)) != c)
+ c = old;
}
-#define ATOMIC64_FETCH_OP(op, c_op) \
-static inline long long atomic64_fetch_##op(long long i, atomic64_t *v) \
-{ \
- long long old, c = 0; \
- while ((old = atomic64_cmpxchg(v, c, c c_op i)) != c) \
- c = old; \
- return old; \
+static inline long long atomic64_fetch_and(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c & i)) != c)
+ c = old;
+
+ return old;
}
-ATOMIC64_FETCH_OP(add, +)
+static inline void atomic64_or(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
-#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
+ while ((old = atomic64_cmpxchg(v, c, c | i)) != c)
+ c = old;
+}
+
+static inline long long atomic64_fetch_or(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c | i)) != c)
+ c = old;
+
+ return old;
+}
-#define ATOMIC64_OPS(op, c_op) \
- ATOMIC64_OP(op, c_op) \
- ATOMIC64_FETCH_OP(op, c_op)
+static inline void atomic64_xor(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c ^ i)) != c)
+ c = old;
+}
-ATOMIC64_OPS(and, &)
-ATOMIC64_OPS(or, |)
-ATOMIC64_OPS(xor, ^)
+static inline long long atomic64_fetch_xor(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c ^ i)) != c)
+ c = old;
+
+ return old;
+}
-#undef ATOMIC64_OPS
-#undef ATOMIC64_FETCH_OP
-#undef ATOMIC64_OP
+static inline long long atomic64_fetch_add(long long i, atomic64_t *v)
+{
+ long long old, c = 0;
+
+ while ((old = atomic64_cmpxchg(v, c, c + i)) != c)
+ c = old;
+
+ return old;
+}
+
+#define atomic64_fetch_sub(i, v) atomic64_fetch_add(-(i), (v))
#endif /* _ASM_X86_ATOMIC64_32_H */
diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h
index 6189a433c9a9..5d9de36a2f04 100644
--- a/arch/x86/include/asm/atomic64_64.h
+++ b/arch/x86/include/asm/atomic64_64.h
@@ -177,7 +177,7 @@ static inline long atomic64_cmpxchg(atomic64_t *v, long old, long new)
}
#define atomic64_try_cmpxchg atomic64_try_cmpxchg
-static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, long *old, long new)
+static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, s64 *old, long new)
{
return try_cmpxchg(&v->counter, old, new);
}
@@ -198,7 +198,7 @@ static inline long atomic64_xchg(atomic64_t *v, long new)
*/
static inline bool atomic64_add_unless(atomic64_t *v, long a, long u)
{
- long c = atomic64_read(v);
+ s64 c = atomic64_read(v);
do {
if (unlikely(c == u))
return false;
@@ -217,7 +217,7 @@ static inline bool atomic64_add_unless(atomic64_t *v, long a, long u)
*/
static inline long atomic64_dec_if_positive(atomic64_t *v)
{
- long dec, c = atomic64_read(v);
+ s64 dec, c = atomic64_read(v);
do {
dec = c - 1;
if (unlikely(dec < 0))
@@ -226,34 +226,55 @@ static inline long atomic64_dec_if_positive(atomic64_t *v)
return dec;
}
-#define ATOMIC64_OP(op) \
-static inline void atomic64_##op(long i, atomic64_t *v) \
-{ \
- asm volatile(LOCK_PREFIX #op"q %1,%0" \
- : "+m" (v->counter) \
- : "er" (i) \
- : "memory"); \
+static inline void atomic64_and(long i, atomic64_t *v)
+{
+ asm volatile(LOCK_PREFIX "andq %1,%0"
+ : "+m" (v->counter)
+ : "er" (i)
+ : "memory");
}
-#define ATOMIC64_FETCH_OP(op, c_op) \
-static inline long atomic64_fetch_##op(long i, atomic64_t *v) \
-{ \
- long val = atomic64_read(v); \
- do { \
- } while (!atomic64_try_cmpxchg(v, &val, val c_op i)); \
- return val; \
+static inline long atomic64_fetch_and(long i, atomic64_t *v)
+{
+ s64 val = atomic64_read(v);
+
+ do {
+ } while (!atomic64_try_cmpxchg(v, &val, val & i));
+ return val;
}
-#define ATOMIC64_OPS(op, c_op) \
- ATOMIC64_OP(op) \
- ATOMIC64_FETCH_OP(op, c_op)
+static inline void atomic64_or(long i, atomic64_t *v)
+{
+ asm volatile(LOCK_PREFIX "orq %1,%0"
+ : "+m" (v->counter)
+ : "er" (i)
+ : "memory");
+}
-ATOMIC64_OPS(and, &)
-ATOMIC64_OPS(or, |)
-ATOMIC64_OPS(xor, ^)
+static inline long atomic64_fetch_or(long i, atomic64_t *v)
+{
+ s64 val = atomic64_read(v);
-#undef ATOMIC64_OPS
-#undef ATOMIC64_FETCH_OP
-#undef ATOMIC64_OP
+ do {
+ } while (!atomic64_try_cmpxchg(v, &val, val | i));
+ return val;
+}
+
+static inline void atomic64_xor(long i, atomic64_t *v)
+{
+ asm volatile(LOCK_PREFIX "xorq %1,%0"
+ : "+m" (v->counter)
+ : "er" (i)
+ : "memory");
+}
+
+static inline long atomic64_fetch_xor(long i, atomic64_t *v)
+{
+ s64 val = atomic64_read(v);
+
+ do {
+ } while (!atomic64_try_cmpxchg(v, &val, val ^ i));
+ return val;
+}
#endif /* _ASM_X86_ATOMIC64_64_H */
diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h
index 39e702d90cdb..aa6b2023d8f8 100644
--- a/arch/x86/include/asm/bug.h
+++ b/arch/x86/include/asm/bug.h
@@ -35,7 +35,7 @@
#define _BUG_FLAGS(ins, flags) \
do { \
asm volatile("1:\t" ins "\n" \
- ".pushsection __bug_table,\"a\"\n" \
+ ".pushsection __bug_table,\"aw\"\n" \
"2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n" \
"\t" __BUG_REL(%c0) "\t# bug_entry::file\n" \
"\t.word %c1" "\t# bug_entry::line\n" \
@@ -52,7 +52,7 @@ do { \
#define _BUG_FLAGS(ins, flags) \
do { \
asm volatile("1:\t" ins "\n" \
- ".pushsection __bug_table,\"a\"\n" \
+ ".pushsection __bug_table,\"aw\"\n" \
"2:\t" __BUG_REL(1b) "\t# bug_entry::bug_addr\n" \
"\t.word %c0" "\t# bug_entry::flags\n" \
"\t.org 2b+%c1\n" \
diff --git a/arch/x86/include/asm/cmpxchg.h b/arch/x86/include/asm/cmpxchg.h
index d90296d061e8..b5069e802d5c 100644
--- a/arch/x86/include/asm/cmpxchg.h
+++ b/arch/x86/include/asm/cmpxchg.h
@@ -157,7 +157,7 @@ extern void __add_wrong_size(void)
#define __raw_try_cmpxchg(_ptr, _pold, _new, size, lock) \
({ \
bool success; \
- __typeof__(_ptr) _old = (_pold); \
+ __typeof__(_ptr) _old = (__typeof__(_ptr))(_pold); \
__typeof__(*(_ptr)) __old = *_old; \
__typeof__(*(_ptr)) __new = (_new); \
switch (size) { \
diff --git a/arch/x86/include/asm/entry_arch.h b/arch/x86/include/asm/entry_arch.h
index df002992d8fd..07b06955a05d 100644
--- a/arch/x86/include/asm/entry_arch.h
+++ b/arch/x86/include/asm/entry_arch.h
@@ -25,6 +25,8 @@ BUILD_INTERRUPT3(kvm_posted_intr_ipi, POSTED_INTR_VECTOR,
smp_kvm_posted_intr_ipi)
BUILD_INTERRUPT3(kvm_posted_intr_wakeup_ipi, POSTED_INTR_WAKEUP_VECTOR,
smp_kvm_posted_intr_wakeup_ipi)
+BUILD_INTERRUPT3(kvm_posted_intr_nested_ipi, POSTED_INTR_NESTED_VECTOR,
+ smp_kvm_posted_intr_nested_ipi)
#endif
/*
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index 9b76cd331990..ad1ed531febc 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -15,6 +15,7 @@ typedef struct {
#ifdef CONFIG_HAVE_KVM
unsigned int kvm_posted_intr_ipis;
unsigned int kvm_posted_intr_wakeup_ipis;
+ unsigned int kvm_posted_intr_nested_ipis;
#endif
unsigned int x86_platform_ipis; /* arch dependent */
unsigned int apic_perf_irqs;
diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index b90e1053049b..d6dbafbd4207 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -30,6 +30,7 @@ extern asmlinkage void apic_timer_interrupt(void);
extern asmlinkage void x86_platform_ipi(void);
extern asmlinkage void kvm_posted_intr_ipi(void);
extern asmlinkage void kvm_posted_intr_wakeup_ipi(void);
+extern asmlinkage void kvm_posted_intr_nested_ipi(void);
extern asmlinkage void error_interrupt(void);
extern asmlinkage void irq_work_interrupt(void);
@@ -62,6 +63,7 @@ extern void trace_call_function_single_interrupt(void);
#define trace_reboot_interrupt reboot_interrupt
#define trace_kvm_posted_intr_ipi kvm_posted_intr_ipi
#define trace_kvm_posted_intr_wakeup_ipi kvm_posted_intr_wakeup_ipi
+#define trace_kvm_posted_intr_nested_ipi kvm_posted_intr_nested_ipi
#endif /* CONFIG_TRACING */
#ifdef CONFIG_X86_LOCAL_APIC
diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 9ada93f01524..1310e1f1cd65 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -296,13 +296,13 @@ static inline unsigned type in##bwl##_p(int port) \
static inline void outs##bwl(int port, const void *addr, unsigned long count) \
{ \
asm volatile("rep; outs" #bwl \
- : "+S"(addr), "+c"(count) : "d"(port)); \
+ : "+S"(addr), "+c"(count) : "d"(port) : "memory"); \
} \
\
static inline void ins##bwl(int port, void *addr, unsigned long count) \
{ \
asm volatile("rep; ins" #bwl \
- : "+D"(addr), "+c"(count) : "d"(port)); \
+ : "+D"(addr), "+c"(count) : "d"(port) : "memory"); \
}
BUILDIO(b, b, char)
diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 6ca9fd6234e1..aaf8d28b5d00 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -83,7 +83,6 @@
*/
#define X86_PLATFORM_IPI_VECTOR 0xf7
-#define POSTED_INTR_WAKEUP_VECTOR 0xf1
/*
* IRQ work vector:
*/
@@ -98,6 +97,8 @@
/* Vector for KVM to deliver posted interrupt IPI */
#ifdef CONFIG_HAVE_KVM
#define POSTED_INTR_VECTOR 0xf2
+#define POSTED_INTR_WAKEUP_VECTOR 0xf1
+#define POSTED_INTR_NESTED_VECTOR 0xf0
#endif
/*
diff --git a/arch/x86/include/asm/kprobes.h b/arch/x86/include/asm/kprobes.h
index 34b984c60790..6cf65437b5e5 100644
--- a/arch/x86/include/asm/kprobes.h
+++ b/arch/x86/include/asm/kprobes.h
@@ -52,10 +52,10 @@ typedef u8 kprobe_opcode_t;
#define flush_insn_slot(p) do { } while (0)
/* optinsn template addresses */
-extern __visible kprobe_opcode_t optprobe_template_entry;
-extern __visible kprobe_opcode_t optprobe_template_val;
-extern __visible kprobe_opcode_t optprobe_template_call;
-extern __visible kprobe_opcode_t optprobe_template_end;
+extern __visible kprobe_opcode_t optprobe_template_entry[];
+extern __visible kprobe_opcode_t optprobe_template_val[];
+extern __visible kprobe_opcode_t optprobe_template_call[];
+extern __visible kprobe_opcode_t optprobe_template_end[];
#define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
#define MAX_OPTINSN_SIZE \
(((unsigned long)&optprobe_template_end - \
diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h
index ecfcb6643c9b..265c907d7d4c 100644
--- a/arch/x86/include/asm/mmu_context.h
+++ b/arch/x86/include/asm/mmu_context.h
@@ -293,7 +293,7 @@ static inline unsigned long __get_current_cr3_fast(void)
unsigned long cr3 = __pa(this_cpu_read(cpu_tlbstate.loaded_mm)->pgd);
/* For now, be very restrictive about when this can be called. */
- VM_WARN_ON(in_nmi() || !in_atomic());
+ VM_WARN_ON(in_nmi() || preemptible());
VM_BUG_ON(cr3 != __read_cr3());
return cr3;
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index cb976bab6299..9ffc36bfe4cd 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -84,7 +84,7 @@ struct pv_init_ops {
*/
unsigned (*patch)(u8 type, u16 clobber, void *insnbuf,
unsigned long addr, unsigned len);
-};
+} __no_randomize_layout;
struct pv_lazy_ops {
@@ -92,12 +92,12 @@ struct pv_lazy_ops {
void (*enter)(void);
void (*leave)(void);
void (*flush)(void);
-};
+} __no_randomize_layout;
struct pv_time_ops {
unsigned long long (*sched_clock)(void);
unsigned long long (*steal_clock)(int cpu);
-};
+} __no_randomize_layout;
struct pv_cpu_ops {
/* hooks for various privileged instructions */
@@ -176,7 +176,7 @@ struct pv_cpu_ops {
void (*start_context_switch)(struct task_struct *prev);
void (*end_context_switch)(struct task_struct *next);
-};
+} __no_randomize_layout;
struct pv_irq_ops {
/*
@@ -199,7 +199,7 @@ struct pv_irq_ops {
#ifdef CONFIG_X86_64
void (*adjust_exception_frame)(void);
#endif
-};
+} __no_randomize_layout;
struct pv_mmu_ops {
unsigned long (*read_cr2)(void);
@@ -305,7 +305,7 @@ struct pv_mmu_ops {
an mfn. We can tell which is which from the index. */
void (*set_fixmap)(unsigned /* enum fixed_addresses */ idx,
phys_addr_t phys, pgprot_t flags);
-};
+} __no_randomize_layout;
struct arch_spinlock;
#ifdef CONFIG_SMP
@@ -322,7 +322,7 @@ struct pv_lock_ops {
void (*kick)(int cpu);
struct paravirt_callee_save vcpu_is_preempted;
-};
+} __no_randomize_layout;
/* This contains all the paravirt structures: we get a convenient
* number for each function using the offset which we use to indicate
@@ -334,7 +334,7 @@ struct paravirt_patch_template {
struct pv_irq_ops pv_irq_ops;
struct pv_mmu_ops pv_mmu_ops;
struct pv_lock_ops pv_lock_ops;
-};
+} __no_randomize_layout;
extern struct pv_info pv_info;
extern struct pv_init_ops pv_init_ops;
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index b27dc9b4a148..0b03d655db7c 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -130,7 +130,7 @@ struct cpuinfo_x86 {
/* Index into per_cpu list: */
u16 cpu_index;
u32 microcode;
-};
+} __randomize_layout;
struct cpuid_regs {
u32 eax, ebx, ecx, edx;
diff --git a/arch/x86/include/asm/refcount.h b/arch/x86/include/asm/refcount.h
new file mode 100644
index 000000000000..ff871210b9f2
--- /dev/null
+++ b/arch/x86/include/asm/refcount.h
@@ -0,0 +1,109 @@
+#ifndef __ASM_X86_REFCOUNT_H
+#define __ASM_X86_REFCOUNT_H
+/*
+ * x86-specific implementation of refcount_t. Based on PAX_REFCOUNT from
+ * PaX/grsecurity.
+ */
+#include <linux/refcount.h>
+
+/*
+ * This is the first portion of the refcount error handling, which lives in
+ * .text.unlikely, and is jumped to from the CPU flag check (in the
+ * following macros). This saves the refcount value location into CX for
+ * the exception handler to use (in mm/extable.c), and then triggers the
+ * central refcount exception. The fixup address for the exception points
+ * back to the regular execution flow in .text.
+ */
+#define _REFCOUNT_EXCEPTION \
+ ".pushsection .text.unlikely\n" \
+ "111:\tlea %[counter], %%" _ASM_CX "\n" \
+ "112:\t" ASM_UD0 "\n" \
+ ASM_UNREACHABLE \
+ ".popsection\n" \
+ "113:\n" \
+ _ASM_EXTABLE_REFCOUNT(112b, 113b)
+
+/* Trigger refcount exception if refcount result is negative. */
+#define REFCOUNT_CHECK_LT_ZERO \
+ "js 111f\n\t" \
+ _REFCOUNT_EXCEPTION
+
+/* Trigger refcount exception if refcount result is zero or negative. */
+#define REFCOUNT_CHECK_LE_ZERO \
+ "jz 111f\n\t" \
+ REFCOUNT_CHECK_LT_ZERO
+
+/* Trigger refcount exception unconditionally. */
+#define REFCOUNT_ERROR \
+ "jmp 111f\n\t" \
+ _REFCOUNT_EXCEPTION
+
+static __always_inline void refcount_add(unsigned int i, refcount_t *r)
+{
+ asm volatile(LOCK_PREFIX "addl %1,%0\n\t"
+ REFCOUNT_CHECK_LT_ZERO
+ : [counter] "+m" (r->refs.counter)
+ : "ir" (i)
+ : "cc", "cx");
+}
+
+static __always_inline void refcount_inc(refcount_t *r)
+{
+ asm volatile(LOCK_PREFIX "incl %0\n\t"
+ REFCOUNT_CHECK_LT_ZERO
+ : [counter] "+m" (r->refs.counter)
+ : : "cc", "cx");
+}
+
+static __always_inline void refcount_dec(refcount_t *r)
+{
+ asm volatile(LOCK_PREFIX "decl %0\n\t"
+ REFCOUNT_CHECK_LE_ZERO
+ : [counter] "+m" (r->refs.counter)
+ : : "cc", "cx");
+}
+
+static __always_inline __must_check
+bool refcount_sub_and_test(unsigned int i, refcount_t *r)
+{
+ GEN_BINARY_SUFFIXED_RMWcc(LOCK_PREFIX "subl", REFCOUNT_CHECK_LT_ZERO,
+ r->refs.counter, "er", i, "%0", e);
+}
+
+static __always_inline __must_check bool refcount_dec_and_test(refcount_t *r)
+{
+ GEN_UNARY_SUFFIXED_RMWcc(LOCK_PREFIX "decl", REFCOUNT_CHECK_LT_ZERO,
+ r->refs.counter, "%0", e);
+}
+
+static __always_inline __must_check
+bool refcount_add_not_zero(unsigned int i, refcount_t *r)
+{
+ int c, result;
+
+ c = atomic_read(&(r->refs));
+ do {
+ if (unlikely(c == 0))
+ return false;
+
+ result = c + i;
+
+ /* Did we try to increment from/to an undesirable state? */
+ if (unlikely(c < 0 || c == INT_MAX || result < c)) {
+ asm volatile(REFCOUNT_ERROR
+ : : [counter] "m" (r->refs.counter)
+ : "cc", "cx");
+ break;
+ }
+
+ } while (!atomic_try_cmpxchg(&(r->refs), &c, result));
+
+ return c != 0;
+}
+
+static __always_inline __must_check bool refcount_inc_not_zero(refcount_t *r)
+{
+ return refcount_add_not_zero(1, r);
+}
+
+#endif
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-24 16:29:44 +0000