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-rw-r--r--arch/i386/kernel/msr.c106
-rw-r--r--arch/i386/lib/msr-on-cpu.c73
2 files changed, 71 insertions, 108 deletions
diff --git a/arch/i386/kernel/msr.c b/arch/i386/kernel/msr.c
index bcaa6e9b6197..8cd0a91ce107 100644
--- a/arch/i386/kernel/msr.c
+++ b/arch/i386/kernel/msr.c
@@ -45,104 +45,6 @@
static struct class *msr_class;
-static inline int wrmsr_eio(u32 reg, u32 eax, u32 edx)
-{
- int err;
-
- err = wrmsr_safe(reg, eax, edx);
- if (err)
- err = -EIO;
- return err;
-}
-
-static inline int rdmsr_eio(u32 reg, u32 *eax, u32 *edx)
-{
- int err;
-
- err = rdmsr_safe(reg, eax, edx);
- if (err)
- err = -EIO;
- return err;
-}
-
-#ifdef CONFIG_SMP
-
-struct msr_command {
- int err;
- u32 reg;
- u32 data[2];
-};
-
-static void msr_smp_wrmsr(void *cmd_block)
-{
- struct msr_command *cmd = (struct msr_command *)cmd_block;
-
- cmd->err = wrmsr_eio(cmd->reg, cmd->data[0], cmd->data[1]);
-}
-
-static void msr_smp_rdmsr(void *cmd_block)
-{
- struct msr_command *cmd = (struct msr_command *)cmd_block;
-
- cmd->err = rdmsr_eio(cmd->reg, &cmd->data[0], &cmd->data[1]);
-}
-
-static inline int do_wrmsr(int cpu, u32 reg, u32 eax, u32 edx)
-{
- struct msr_command cmd;
- int ret;
-
- preempt_disable();
- if (cpu == smp_processor_id()) {
- ret = wrmsr_eio(reg, eax, edx);
- } else {
- cmd.reg = reg;
- cmd.data[0] = eax;
- cmd.data[1] = edx;
-
- smp_call_function_single(cpu, msr_smp_wrmsr, &cmd, 1, 1);
- ret = cmd.err;
- }
- preempt_enable();
- return ret;
-}
-
-static inline int do_rdmsr(int cpu, u32 reg, u32 * eax, u32 * edx)
-{
- struct msr_command cmd;
- int ret;
-
- preempt_disable();
- if (cpu == smp_processor_id()) {
- ret = rdmsr_eio(reg, eax, edx);
- } else {
- cmd.reg = reg;
-
- smp_call_function_single(cpu, msr_smp_rdmsr, &cmd, 1, 1);
-
- *eax = cmd.data[0];
- *edx = cmd.data[1];
-
- ret = cmd.err;
- }
- preempt_enable();
- return ret;
-}
-
-#else /* ! CONFIG_SMP */
-
-static inline int do_wrmsr(int cpu, u32 reg, u32 eax, u32 edx)
-{
- return wrmsr_eio(reg, eax, edx);
-}
-
-static inline int do_rdmsr(int cpu, u32 reg, u32 *eax, u32 *edx)
-{
- return rdmsr_eio(reg, eax, edx);
-}
-
-#endif /* ! CONFIG_SMP */
-
static loff_t msr_seek(struct file *file, loff_t offset, int orig)
{
loff_t ret = -EINVAL;
@@ -174,9 +76,9 @@ static ssize_t msr_read(struct file *file, char __user * buf,
return -EINVAL; /* Invalid chunk size */
for (; count; count -= 8) {
- err = do_rdmsr(cpu, reg, &data[0], &data[1]);
+ err = rdmsr_safe_on_cpu(cpu, reg, &data[0], &data[1]);
if (err)
- return err;
+ return -EIO;
if (copy_to_user(tmp, &data, 8))
return -EFAULT;
tmp += 2;
@@ -200,9 +102,9 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
for (; count; count -= 8) {
if (copy_from_user(&data, tmp, 8))
return -EFAULT;
- err = do_wrmsr(cpu, reg, data[0], data[1]);
+ err = wrmsr_safe_on_cpu(cpu, reg, data[0], data[1]);
if (err)
- return err;
+ return -EIO;
tmp += 2;
}
diff --git a/arch/i386/lib/msr-on-cpu.c b/arch/i386/lib/msr-on-cpu.c
index 1c46bda409ff..7767962f25d3 100644
--- a/arch/i386/lib/msr-on-cpu.c
+++ b/arch/i386/lib/msr-on-cpu.c
@@ -6,6 +6,7 @@
struct msr_info {
u32 msr_no;
u32 l, h;
+ int err;
};
static void __rdmsr_on_cpu(void *info)
@@ -15,20 +16,38 @@ static void __rdmsr_on_cpu(void *info)
rdmsr(rv->msr_no, rv->l, rv->h);
}
-void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
+static void __rdmsr_safe_on_cpu(void *info)
{
+ struct msr_info *rv = info;
+
+ rv->err = rdmsr_safe(rv->msr_no, &rv->l, &rv->h);
+}
+
+static int _rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h, int safe)
+{
+ int err = 0;
preempt_disable();
if (smp_processor_id() == cpu)
- rdmsr(msr_no, *l, *h);
+ if (safe)
+ err = rdmsr_safe(msr_no, l, h);
+ else
+ rdmsr(msr_no, *l, *h);
else {
struct msr_info rv;
rv.msr_no = msr_no;
- smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1);
+ if (safe) {
+ smp_call_function_single(cpu, __rdmsr_safe_on_cpu,
+ &rv, 0, 1);
+ err = rv.err;
+ } else {
+ smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1);
+ }
*l = rv.l;
*h = rv.h;
}
preempt_enable();
+ return err;
}
static void __wrmsr_on_cpu(void *info)
@@ -38,21 +57,63 @@ static void __wrmsr_on_cpu(void *info)
wrmsr(rv->msr_no, rv->l, rv->h);
}
-void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+static void __wrmsr_safe_on_cpu(void *info)
{
+ struct msr_info *rv = info;
+
+ rv->err = wrmsr_safe(rv->msr_no, rv->l, rv->h);
+}
+
+static int _wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h, int safe)
+{
+ int err = 0;
preempt_disable();
if (smp_processor_id() == cpu)
- wrmsr(msr_no, l, h);
+ if (safe)
+ err = wrmsr_safe(msr_no, l, h);
+ else
+ wrmsr(msr_no, l, h);
else {
struct msr_info rv;
rv.msr_no = msr_no;
rv.l = l;
rv.h = h;
- smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1);
+ if (safe) {
+ smp_call_function_single(cpu, __wrmsr_safe_on_cpu,
+ &rv, 0, 1);
+ err = rv.err;
+ } else {
+ smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1);
+ }
}
preempt_enable();
+ return err;
+}
+
+void wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+{
+ _wrmsr_on_cpu(cpu, msr_no, l, h, 0);
+}
+
+void rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
+{
+ _rdmsr_on_cpu(cpu, msr_no, l, h, 0);
+}
+
+/* These "safe" variants are slower and should be used when the target MSR
+ may not actually exist. */
+int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
+{
+ return _wrmsr_on_cpu(cpu, msr_no, l, h, 1);
+}
+
+int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
+{
+ return _rdmsr_on_cpu(cpu, msr_no, l, h, 1);
}
EXPORT_SYMBOL(rdmsr_on_cpu);
EXPORT_SYMBOL(wrmsr_on_cpu);
+EXPORT_SYMBOL(rdmsr_safe_on_cpu);
+EXPORT_SYMBOL(wrmsr_safe_on_cpu);