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-rw-r--r--arch/x86/lib/msr.c227
1 files changed, 12 insertions, 215 deletions
diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c
index 33a1e3ca22d8..8f8eebdca7d4 100644
--- a/arch/x86/lib/msr.c
+++ b/arch/x86/lib/msr.c
@@ -1,226 +1,23 @@
1#include <linux/module.h> 1#include <linux/module.h>
2#include <linux/preempt.h> 2#include <linux/preempt.h>
3#include <linux/smp.h>
4#include <asm/msr.h> 3#include <asm/msr.h>
5 4
6struct msr_info { 5struct msr *msrs_alloc(void)
7 u32 msr_no;
8 struct msr reg;
9 struct msr *msrs;
10 int off;
11 int err;
12};
13
14static void __rdmsr_on_cpu(void *info)
15{
16 struct msr_info *rv = info;
17 struct msr *reg;
18 int this_cpu = raw_smp_processor_id();
19
20 if (rv->msrs)
21 reg = &rv->msrs[this_cpu - rv->off];
22 else
23 reg = &rv->reg;
24
25 rdmsr(rv->msr_no, reg->l, reg->h);
26}
27
28static void __wrmsr_on_cpu(void *info)
29{
30 struct msr_info *rv = info;
31 struct msr *reg;
32 int this_cpu = raw_smp_processor_id();
33
34 if (rv->msrs)
35 reg = &rv->msrs[this_cpu - rv->off];
36 else
37 reg = &rv->reg;
38
39 wrmsr(rv->msr_no, reg->l, reg->h);
40}
41
42int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
43{
44 int err;
45 struct msr_info rv;
46
47 memset(&rv, 0, sizeof(rv));
48
49 rv.msr_no = msr_no;
50 err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
51 *l = rv.reg.l;
52 *h = rv.reg.h;
53
54 return err;
55}
56EXPORT_SYMBOL(rdmsr_on_cpu);
57
58int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h)
59{
60 int err;
61 struct msr_info rv;
62
63 memset(&rv, 0, sizeof(rv));
64
65 rv.msr_no = msr_no;
66 rv.reg.l = l;
67 rv.reg.h = h;
68 err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
69
70 return err;
71}
72EXPORT_SYMBOL(wrmsr_on_cpu);
73
74/* rdmsr on a bunch of CPUs
75 *
76 * @mask: which CPUs
77 * @msr_no: which MSR
78 * @msrs: array of MSR values
79 *
80 */
81void rdmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs)
82{
83 struct msr_info rv;
84 int this_cpu;
85
86 memset(&rv, 0, sizeof(rv));
87
88 rv.off = cpumask_first(mask);
89 rv.msrs = msrs;
90 rv.msr_no = msr_no;
91
92 this_cpu = get_cpu();
93
94 if (cpumask_test_cpu(this_cpu, mask))
95 __rdmsr_on_cpu(&rv);
96
97 smp_call_function_many(mask, __rdmsr_on_cpu, &rv, 1);
98 put_cpu();
99}
100EXPORT_SYMBOL(rdmsr_on_cpus);
101
102/*
103 * wrmsr on a bunch of CPUs
104 *
105 * @mask: which CPUs
106 * @msr_no: which MSR
107 * @msrs: array of MSR values
108 *
109 */
110void wrmsr_on_cpus(const cpumask_t *mask, u32 msr_no, struct msr *msrs)
111{
112 struct msr_info rv;
113 int this_cpu;
114
115 memset(&rv, 0, sizeof(rv));
116
117 rv.off = cpumask_first(mask);
118 rv.msrs = msrs;
119 rv.msr_no = msr_no;
120
121 this_cpu = get_cpu();
122
123 if (cpumask_test_cpu(this_cpu, mask))
124 __wrmsr_on_cpu(&rv);
125
126 smp_call_function_many(mask, __wrmsr_on_cpu, &rv, 1);
127 put_cpu();
128}
129EXPORT_SYMBOL(wrmsr_on_cpus);
130
131/* These "safe" variants are slower and should be used when the target MSR
132 may not actually exist. */
133static void __rdmsr_safe_on_cpu(void *info)
134{
135 struct msr_info *rv = info;
136
137 rv->err = rdmsr_safe(rv->msr_no, &rv->reg.l, &rv->reg.h);
138}
139
140static void __wrmsr_safe_on_cpu(void *info)
141{
142 struct msr_info *rv = info;
143
144 rv->err = wrmsr_safe(rv->msr_no, rv->reg.l, rv->reg.h);
145}
146
147int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h)
148{ 6{
149 int err; 7 struct msr *msrs = NULL;
150 struct msr_info rv;
151 8
152 memset(&rv, 0, sizeof(rv)); 9 msrs = alloc_percpu(struct msr);
10 if (!msrs) {
11 pr_warning("%s: error allocating msrs\n", __func__);
12 return NULL;
13 }
153 14
154 rv.msr_no = msr_no; 15 return msrs;
155 err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1);
156 *l = rv.reg.l;
157 *h = rv.reg.h;
158
159 return err ? err : rv.err;
160} 16}
161EXPORT_SYMBOL(rdmsr_safe_on_cpu); 17EXPORT_SYMBOL(msrs_alloc);
162 18
163int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) 19void msrs_free(struct msr *msrs)
164{ 20{
165 int err; 21 free_percpu(msrs);
166 struct msr_info rv;
167
168 memset(&rv, 0, sizeof(rv));
169
170 rv.msr_no = msr_no;
171 rv.reg.l = l;
172 rv.reg.h = h;
173 err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1);
174
175 return err ? err : rv.err;
176}
177EXPORT_SYMBOL(wrmsr_safe_on_cpu);
178
179/*
180 * These variants are significantly slower, but allows control over
181 * the entire 32-bit GPR set.
182 */
183struct msr_regs_info {
184 u32 *regs;
185 int err;
186};
187
188static void __rdmsr_safe_regs_on_cpu(void *info)
189{
190 struct msr_regs_info *rv = info;
191
192 rv->err = rdmsr_safe_regs(rv->regs);
193}
194
195static void __wrmsr_safe_regs_on_cpu(void *info)
196{
197 struct msr_regs_info *rv = info;
198
199 rv->err = wrmsr_safe_regs(rv->regs);
200}
201
202int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
203{
204 int err;
205 struct msr_regs_info rv;
206
207 rv.regs = regs;
208 rv.err = -EIO;
209 err = smp_call_function_single(cpu, __rdmsr_safe_regs_on_cpu, &rv, 1);
210
211 return err ? err : rv.err;
212}
213EXPORT_SYMBOL(rdmsr_safe_regs_on_cpu);
214
215int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs)
216{
217 int err;
218 struct msr_regs_info rv;
219
220 rv.regs = regs;
221 rv.err = -EIO;
222 err = smp_call_function_single(cpu, __wrmsr_safe_regs_on_cpu, &rv, 1);
223
224 return err ? err : rv.err;
225} 22}
226EXPORT_SYMBOL(wrmsr_safe_regs_on_cpu); 23EXPORT_SYMBOL(msrs_free);