1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/export.h> 3 #include <linux/preempt.h> 4 #include <linux/smp.h> 5 #include <asm/msr.h> 6 7 static void __rdmsr_on_cpu(void *info) 8 { 9 struct msr_info *rv = info; 10 struct msr *reg; 11 int this_cpu = raw_smp_processor_id(); 12 13 if (rv->msrs) 14 reg = per_cpu_ptr(rv->msrs, this_cpu); 15 else 16 reg = &rv->reg; 17 18 rdmsr(rv->msr_no, reg->l, reg->h); 19 } 20 21 static void __wrmsr_on_cpu(void *info) 22 { 23 struct msr_info *rv = info; 24 struct msr *reg; 25 int this_cpu = raw_smp_processor_id(); 26 27 if (rv->msrs) 28 reg = per_cpu_ptr(rv->msrs, this_cpu); 29 else 30 reg = &rv->reg; 31 32 wrmsr(rv->msr_no, reg->l, reg->h); 33 } 34 35 int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) 36 { 37 int err; 38 struct msr_info rv; 39 40 memset(&rv, 0, sizeof(rv)); 41 42 rv.msr_no = msr_no; 43 err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1); 44 *l = rv.reg.l; 45 *h = rv.reg.h; 46 47 return err; 48 } 49 EXPORT_SYMBOL(rdmsr_on_cpu); 50 51 int rdmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 *q) 52 { 53 int err; 54 struct msr_info rv; 55 56 memset(&rv, 0, sizeof(rv)); 57 58 rv.msr_no = msr_no; 59 err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1); 60 *q = rv.reg.q; 61 62 return err; 63 } 64 EXPORT_SYMBOL(rdmsrl_on_cpu); 65 66 int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) 67 { 68 int err; 69 struct msr_info rv; 70 71 memset(&rv, 0, sizeof(rv)); 72 73 rv.msr_no = msr_no; 74 rv.reg.l = l; 75 rv.reg.h = h; 76 err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1); 77 78 return err; 79 } 80 EXPORT_SYMBOL(wrmsr_on_cpu); 81 82 int wrmsrl_on_cpu(unsigned int cpu, u32 msr_no, u64 q) 83 { 84 int err; 85 struct msr_info rv; 86 87 memset(&rv, 0, sizeof(rv)); 88 89 rv.msr_no = msr_no; 90 rv.reg.q = q; 91 92 err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1); 93 94 return err; 95 } 96 EXPORT_SYMBOL(wrmsrl_on_cpu); 97 98 static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no, 99 struct msr *msrs, 100 void (*msr_func) (void *info)) 101 { 102 struct msr_info rv; 103 int this_cpu; 104 105 memset(&rv, 0, sizeof(rv)); 106 107 rv.msrs = msrs; 108 rv.msr_no = msr_no; 109 110 this_cpu = get_cpu(); 111 112 if (cpumask_test_cpu(this_cpu, mask)) 113 msr_func(&rv); 114 115 smp_call_function_many(mask, msr_func, &rv, 1); 116 put_cpu(); 117 } 118 119 /* rdmsr on a bunch of CPUs 120 * 121 * @mask: which CPUs 122 * @msr_no: which MSR 123 * @msrs: array of MSR values 124 * 125 */ 126 void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs) 127 { 128 __rwmsr_on_cpus(mask, msr_no, msrs, __rdmsr_on_cpu); 129 } 130 EXPORT_SYMBOL(rdmsr_on_cpus); 131 132 /* 133 * wrmsr on a bunch of CPUs 134 * 135 * @mask: which CPUs 136 * @msr_no: which MSR 137 * @msrs: array of MSR values 138 * 139 */ 140 void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs) 141 { 142 __rwmsr_on_cpus(mask, msr_no, msrs, __wrmsr_on_cpu); 143 } 144 EXPORT_SYMBOL(wrmsr_on_cpus); 145 146 /* These "safe" variants are slower and should be used when the target MSR 147 may not actually exist. */ 148 static void __rdmsr_safe_on_cpu(void *info) 149 { 150 struct msr_info *rv = info; 151 152 rv->err = rdmsr_safe(rv->msr_no, &rv->reg.l, &rv->reg.h); 153 } 154 155 static void __wrmsr_safe_on_cpu(void *info) 156 { 157 struct msr_info *rv = info; 158 159 rv->err = wrmsr_safe(rv->msr_no, rv->reg.l, rv->reg.h); 160 } 161 162 int rdmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h) 163 { 164 int err; 165 struct msr_info rv; 166 167 memset(&rv, 0, sizeof(rv)); 168 169 rv.msr_no = msr_no; 170 err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1); 171 *l = rv.reg.l; 172 *h = rv.reg.h; 173 174 return err ? err : rv.err; 175 } 176 EXPORT_SYMBOL(rdmsr_safe_on_cpu); 177 178 int wrmsr_safe_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h) 179 { 180 int err; 181 struct msr_info rv; 182 183 memset(&rv, 0, sizeof(rv)); 184 185 rv.msr_no = msr_no; 186 rv.reg.l = l; 187 rv.reg.h = h; 188 err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1); 189 190 return err ? err : rv.err; 191 } 192 EXPORT_SYMBOL(wrmsr_safe_on_cpu); 193 194 int wrmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q) 195 { 196 int err; 197 struct msr_info rv; 198 199 memset(&rv, 0, sizeof(rv)); 200 201 rv.msr_no = msr_no; 202 rv.reg.q = q; 203 204 err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1); 205 206 return err ? err : rv.err; 207 } 208 EXPORT_SYMBOL(wrmsrl_safe_on_cpu); 209 210 int rdmsrl_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q) 211 { 212 int err; 213 struct msr_info rv; 214 215 memset(&rv, 0, sizeof(rv)); 216 217 rv.msr_no = msr_no; 218 err = smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 1); 219 *q = rv.reg.q; 220 221 return err ? err : rv.err; 222 } 223 EXPORT_SYMBOL(rdmsrl_safe_on_cpu); 224 225 /* 226 * These variants are significantly slower, but allows control over 227 * the entire 32-bit GPR set. 228 */ 229 static void __rdmsr_safe_regs_on_cpu(void *info) 230 { 231 struct msr_regs_info *rv = info; 232 233 rv->err = rdmsr_safe_regs(rv->regs); 234 } 235 236 static void __wrmsr_safe_regs_on_cpu(void *info) 237 { 238 struct msr_regs_info *rv = info; 239 240 rv->err = wrmsr_safe_regs(rv->regs); 241 } 242 243 int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs) 244 { 245 int err; 246 struct msr_regs_info rv; 247 248 rv.regs = regs; 249 rv.err = -EIO; 250 err = smp_call_function_single(cpu, __rdmsr_safe_regs_on_cpu, &rv, 1); 251 252 return err ? err : rv.err; 253 } 254 EXPORT_SYMBOL(rdmsr_safe_regs_on_cpu); 255 256 int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 *regs) 257 { 258 int err; 259 struct msr_regs_info rv; 260 261 rv.regs = regs; 262 rv.err = -EIO; 263 err = smp_call_function_single(cpu, __wrmsr_safe_regs_on_cpu, &rv, 1); 264 265 return err ? err : rv.err; 266 } 267 EXPORT_SYMBOL(wrmsr_safe_regs_on_cpu); 268