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-rw-r--r--arch/x86/lib/Makefile3
-rw-r--r--arch/x86/lib/atomic64_32.c230
-rw-r--r--arch/x86/lib/clear_page_64.S5
-rw-r--r--arch/x86/lib/copy_user_64.S1
-rw-r--r--arch/x86/lib/msr-reg-export.c5
-rw-r--r--arch/x86/lib/msr-reg.S102
-rw-r--r--arch/x86/lib/msr.c75
-rw-r--r--arch/x86/lib/usercopy_32.c2
8 files changed, 403 insertions, 20 deletions
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index f9d35632666..9e609206fac 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -9,7 +9,10 @@ lib-y += thunk_$(BITS).o
lib-y += usercopy_$(BITS).o getuser.o putuser.o
lib-y += memcpy_$(BITS).o
+obj-y += msr-reg.o msr-reg-export.o
+
ifeq ($(CONFIG_X86_32),y)
+ obj-y += atomic64_32.o
lib-y += checksum_32.o
lib-y += strstr_32.o
lib-y += semaphore_32.o string_32.o
diff --git a/arch/x86/lib/atomic64_32.c b/arch/x86/lib/atomic64_32.c
new file mode 100644
index 00000000000..824fa0be55a
--- /dev/null
+++ b/arch/x86/lib/atomic64_32.c
@@ -0,0 +1,230 @@
+#include <linux/compiler.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <asm/processor.h>
+#include <asm/cmpxchg.h>
+#include <asm/atomic.h>
+
+static noinline u64 cmpxchg8b(u64 *ptr, u64 old, u64 new)
+{
+ u32 low = new;
+ u32 high = new >> 32;
+
+ asm volatile(
+ LOCK_PREFIX "cmpxchg8b %1\n"
+ : "+A" (old), "+m" (*ptr)
+ : "b" (low), "c" (high)
+ );
+ return old;
+}
+
+u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val)
+{
+ return cmpxchg8b(&ptr->counter, old_val, new_val);
+}
+EXPORT_SYMBOL(atomic64_cmpxchg);
+
+/**
+ * atomic64_xchg - xchg atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically xchgs the value of @ptr to @new_val and returns
+ * the old value.
+ */
+u64 atomic64_xchg(atomic64_t *ptr, u64 new_val)
+{
+ /*
+ * Try first with a (possibly incorrect) assumption about
+ * what we have there. We'll do two loops most likely,
+ * but we'll get an ownership MESI transaction straight away
+ * instead of a read transaction followed by a
+ * flush-for-ownership transaction:
+ */
+ u64 old_val, real_val = 0;
+
+ do {
+ old_val = real_val;
+
+ real_val = atomic64_cmpxchg(ptr, old_val, new_val);
+
+ } while (real_val != old_val);
+
+ return old_val;
+}
+EXPORT_SYMBOL(atomic64_xchg);
+
+/**
+ * atomic64_set - set atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ * @new_val: value to assign
+ *
+ * Atomically sets the value of @ptr to @new_val.
+ */
+void atomic64_set(atomic64_t *ptr, u64 new_val)
+{
+ atomic64_xchg(ptr, new_val);
+}
+EXPORT_SYMBOL(atomic64_set);
+
+/**
+EXPORT_SYMBOL(atomic64_read);
+ * atomic64_add_return - add and return
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns @delta + *@ptr
+ */
+noinline u64 atomic64_add_return(u64 delta, atomic64_t *ptr)
+{
+ /*
+ * Try first with a (possibly incorrect) assumption about
+ * what we have there. We'll do two loops most likely,
+ * but we'll get an ownership MESI transaction straight away
+ * instead of a read transaction followed by a
+ * flush-for-ownership transaction:
+ */
+ u64 old_val, new_val, real_val = 0;
+
+ do {
+ old_val = real_val;
+ new_val = old_val + delta;
+
+ real_val = atomic64_cmpxchg(ptr, old_val, new_val);
+
+ } while (real_val != old_val);
+
+ return new_val;
+}
+EXPORT_SYMBOL(atomic64_add_return);
+
+u64 atomic64_sub_return(u64 delta, atomic64_t *ptr)
+{
+ return atomic64_add_return(-delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_sub_return);
+
+u64 atomic64_inc_return(atomic64_t *ptr)
+{
+ return atomic64_add_return(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc_return);
+
+u64 atomic64_dec_return(atomic64_t *ptr)
+{
+ return atomic64_sub_return(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec_return);
+
+/**
+ * atomic64_add - add integer to atomic64 variable
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr.
+ */
+void atomic64_add(u64 delta, atomic64_t *ptr)
+{
+ atomic64_add_return(delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_add);
+
+/**
+ * atomic64_sub - subtract the atomic64 variable
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr.
+ */
+void atomic64_sub(u64 delta, atomic64_t *ptr)
+{
+ atomic64_add(-delta, ptr);
+}
+EXPORT_SYMBOL(atomic64_sub);
+
+/**
+ * atomic64_sub_and_test - subtract value from variable and test result
+ * @delta: integer value to subtract
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically subtracts @delta from @ptr and returns
+ * true if the result is zero, or false for all
+ * other cases.
+ */
+int atomic64_sub_and_test(u64 delta, atomic64_t *ptr)
+{
+ u64 new_val = atomic64_sub_return(delta, ptr);
+
+ return new_val == 0;
+}
+EXPORT_SYMBOL(atomic64_sub_and_test);
+
+/**
+ * atomic64_inc - increment atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1.
+ */
+void atomic64_inc(atomic64_t *ptr)
+{
+ atomic64_add(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc);
+
+/**
+ * atomic64_dec - decrement atomic64 variable
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1.
+ */
+void atomic64_dec(atomic64_t *ptr)
+{
+ atomic64_sub(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec);
+
+/**
+ * atomic64_dec_and_test - decrement and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically decrements @ptr by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+int atomic64_dec_and_test(atomic64_t *ptr)
+{
+ return atomic64_sub_and_test(1, ptr);
+}
+EXPORT_SYMBOL(atomic64_dec_and_test);
+
+/**
+ * atomic64_inc_and_test - increment and test
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically increments @ptr by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+int atomic64_inc_and_test(atomic64_t *ptr)
+{
+ return atomic64_sub_and_test(-1, ptr);
+}
+EXPORT_SYMBOL(atomic64_inc_and_test);
+
+/**
+ * atomic64_add_negative - add and test if negative
+ * @delta: integer value to add
+ * @ptr: pointer to type atomic64_t
+ *
+ * Atomically adds @delta to @ptr and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero.
+ */
+int atomic64_add_negative(u64 delta, atomic64_t *ptr)
+{
+ s64 new_val = atomic64_add_return(delta, ptr);
+
+ return new_val < 0;
+}
+EXPORT_SYMBOL(atomic64_add_negative);
diff --git a/arch/x86/lib/clear_page_64.S b/arch/x86/lib/clear_page_64.S
index 9a10a78bb4a..ebeafcce04a 100644
--- a/arch/x86/lib/clear_page_64.S
+++ b/arch/x86/lib/clear_page_64.S
@@ -5,15 +5,14 @@
* Zero a page.
* rdi page
*/
- ALIGN
-clear_page_c:
+ENTRY(clear_page_c)
CFI_STARTPROC
movl $4096/8,%ecx
xorl %eax,%eax
rep stosq
ret
CFI_ENDPROC
-ENDPROC(clear_page)
+ENDPROC(clear_page_c)
ENTRY(clear_page)
CFI_STARTPROC
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index f118c110af3..6ba0f7bb85e 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -75,6 +75,7 @@ ENTRY(copy_to_user)
jae bad_to_user
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
+ENDPROC(copy_to_user)
/* Standard copy_from_user with segment limit checking */
ENTRY(copy_from_user)
diff --git a/arch/x86/lib/msr-reg-export.c b/arch/x86/lib/msr-reg-export.c
new file mode 100644
index 00000000000..a311cc59b65
--- /dev/null
+++ b/arch/x86/lib/msr-reg-export.c
@@ -0,0 +1,5 @@
+#include <linux/module.h>
+#include <asm/msr.h>
+
+EXPORT_SYMBOL(native_rdmsr_safe_regs);
+EXPORT_SYMBOL(native_wrmsr_safe_regs);
diff --git a/arch/x86/lib/msr-reg.S b/arch/x86/lib/msr-reg.S
new file mode 100644
index 00000000000..69fa10623f2
--- /dev/null
+++ b/arch/x86/lib/msr-reg.S
@@ -0,0 +1,102 @@
+#include <linux/linkage.h>
+#include <linux/errno.h>
+#include <asm/dwarf2.h>
+#include <asm/asm.h>
+#include <asm/msr.h>
+
+#ifdef CONFIG_X86_64
+/*
+ * int native_{rdmsr,wrmsr}_safe_regs(u32 gprs[8]);
+ *
+ * reg layout: u32 gprs[eax, ecx, edx, ebx, esp, ebp, esi, edi]
+ *
+ */
+.macro op_safe_regs op
+ENTRY(native_\op\()_safe_regs)
+ CFI_STARTPROC
+ pushq_cfi %rbx
+ pushq_cfi %rbp
+ movq %rdi, %r10 /* Save pointer */
+ xorl %r11d, %r11d /* Return value */
+ movl (%rdi), %eax
+ movl 4(%rdi), %ecx
+ movl 8(%rdi), %edx
+ movl 12(%rdi), %ebx
+ movl 20(%rdi), %ebp
+ movl 24(%rdi), %esi
+ movl 28(%rdi), %edi
+ CFI_REMEMBER_STATE
+1: \op
+2: movl %eax, (%r10)
+ movl %r11d, %eax /* Return value */
+ movl %ecx, 4(%r10)
+ movl %edx, 8(%r10)
+ movl %ebx, 12(%r10)
+ movl %ebp, 20(%r10)
+ movl %esi, 24(%r10)
+ movl %edi, 28(%r10)
+ popq_cfi %rbp
+ popq_cfi %rbx
+ ret
+3:
+ CFI_RESTORE_STATE
+ movl $-EIO, %r11d
+ jmp 2b
+
+ _ASM_EXTABLE(1b, 3b)
+ CFI_ENDPROC
+ENDPROC(native_\op\()_safe_regs)
+.endm
+
+#else /* X86_32 */
+
+.macro op_safe_regs op
+ENTRY(native_\op\()_safe_regs)
+ CFI_STARTPROC
+ pushl_cfi %ebx
+ pushl_cfi %ebp
+ pushl_cfi %esi
+ pushl_cfi %edi
+ pushl_cfi $0 /* Return value */
+ pushl_cfi %eax
+ movl 4(%eax), %ecx
+ movl 8(%eax), %edx
+ movl 12(%eax), %ebx
+ movl 20(%eax), %ebp
+ movl 24(%eax), %esi
+ movl 28(%eax), %edi
+ movl (%eax), %eax
+ CFI_REMEMBER_STATE
+1: \op
+2: pushl_cfi %eax
+ movl 4(%esp), %eax
+ popl_cfi (%eax)
+ addl $4, %esp
+ CFI_ADJUST_CFA_OFFSET -4
+ movl %ecx, 4(%eax)
+ movl %edx, 8(%eax)
+ movl %ebx, 12(%eax)
+ movl %ebp, 20(%eax)
+ movl %esi, 24(%eax)
+ movl %edi, 28(%eax)
+ popl_cfi %eax
+ popl_cfi %edi
+ popl_cfi %esi
+ popl_cfi %ebp
+ popl_cfi %ebx
+ ret
+3:
+ CFI_RESTORE_STATE
+ movl $-EIO, 4(%esp)
+ jmp 2b
+
+ _ASM_EXTABLE(1b, 3b)
+ CFI_ENDPROC
+ENDPROC(native_\op\()_safe_regs)
+.endm
+
+#endif
+
+op_safe_regs rdmsr
+op_safe_regs wrmsr
+
diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c
index 1440b9c0547..33a1e3ca22d 100644
--- a/arch/x86/lib/msr.c
+++ b/arch/x86/lib/msr.c
@@ -89,16 +89,13 @@ void rdmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs)
rv.msrs = msrs;
rv.msr_no = msr_no;
- preempt_disable();
- /*
- * FIXME: handle the CPU we're executing on separately for now until
- * smp_call_function_many has been fixed to not skip it.
- */
- this_cpu = raw_smp_processor_id();
- smp_call_function_single(this_cpu, __rdmsr_on_cpu, &rv, 1);
+ this_cpu = get_cpu();
+
+ if (cpumask_test_cpu(this_cpu, mask))
+ __rdmsr_on_cpu(&rv);
smp_call_function_many(mask, __rdmsr_on_cpu, &rv, 1);
- preempt_enable();
+ put_cpu();
}
EXPORT_SYMBOL(rdmsr_on_cpus);
@@ -121,16 +118,13 @@ void wrmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs)
rv.msrs = msrs;
rv.msr_no = msr_no;
- preempt_disable();
- /*
- * FIXME: handle the CPU we're executing on separately for now until
- * smp_call_function_many has been fixed to not skip it.
- */
- this_cpu = raw_smp_processor_id();
- smp_call_function_single(this_cpu, __wrmsr_on_cpu, &rv, 1);
+ this_cpu = get_cpu();
+
+ if (cpumask_test_cpu(this_cpu, mask))
+ __wrmsr_on_cpu(&rv);
smp_call_function_many(mask, __wrmsr_on_cpu, &rv, 1);
- preempt_enable();
+ put_cpu();
}
EXPORT_SYMBOL(wrmsr_on_cpus);
@@ -181,3 +175,52 @@ int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
return err ? err : rv.err;
}
EXPORT_SYMBOL(wrmsr_safe_on_cpu);
+
+/*
+ * These variants are significantly slower, but allows control over
+ * the entire 32-bit GPR set.
+ */
+struct msr_regs_info {
+ u32 *regs;
+ int err;
+};
+
+static void __rdmsr_safe_regs_on_cpu(void *info)
+{
+ struct msr_regs_info *rv = info;
+
+ rv->err = rdmsr_safe_regs(rv->regs);
+}
+
+static void __wrmsr_safe_regs_on_cpu(void *info)
+{
+ struct msr_regs_info *rv = info;
+
+ rv->err = wrmsr_safe_regs(rv->regs);
+}
+
+int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
+{
+ int err;
+ struct msr_regs_info rv;
+
+ rv.regs = regs;
+ rv.err = -EIO;
+ err = smp_call_function_single(cpu, __rdmsr_safe_regs_on_cpu, &rv, 1);
+
+ return err ? err : rv.err;
+}
+EXPORT_SYMBOL(rdmsr_safe_regs_on_cpu);
+
+int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
+{
+ int err;
+ struct msr_regs_info rv;
+
+ rv.regs = regs;
+ rv.err = -EIO;
+ err = smp_call_function_single(cpu, __wrmsr_safe_regs_on_cpu, &rv, 1);
+
+ return err ? err : rv.err;
+}
+EXPORT_SYMBOL(wrmsr_safe_regs_on_cpu);
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c
index 7c8ca91bb9e..1f118d462ac 100644
--- a/arch/x86/lib/usercopy_32.c
+++ b/arch/x86/lib/usercopy_32.c
@@ -751,7 +751,7 @@ survive:
if (retval == -ENOMEM && is_global_init(current)) {
up_read(&current->mm->mmap_sem);
- congestion_wait(WRITE, HZ/50);
+ congestion_wait(BLK_RW_ASYNC, HZ/50);
goto survive;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-03-13 15:03:47 +0000