Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * Copyright (C) 1994 Linus Torvalds |
| 3 | * |
| 4 | * Pentium III FXSR, SSE support |
| 5 | * General FPU state handling cleanups |
| 6 | * Gareth Hughes <gareth@valinux.com>, May 2000 |
| 7 | */ |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 8 | #include <linux/module.h> |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 9 | #include <linux/regset.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 10 | #include <linux/sched.h> |
| 11 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/sigcontext.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 13 | #include <asm/processor.h> |
| 14 | #include <asm/math_emu.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <asm/uaccess.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 16 | #include <asm/ptrace.h> |
| 17 | #include <asm/i387.h> |
| 18 | #include <asm/user.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 20 | #ifdef CONFIG_X86_64 |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 21 | # include <asm/sigcontext32.h> |
| 22 | # include <asm/user32.h> |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 23 | #else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 24 | # define save_i387_xstate_ia32 save_i387_xstate |
| 25 | # define restore_i387_xstate_ia32 restore_i387_xstate |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 26 | # define _fpstate_ia32 _fpstate |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 27 | # define _xstate_ia32 _xstate |
Suresh Siddha | 3c1c7f1 | 2008-07-29 10:29:21 -0700 | [diff] [blame] | 28 | # define sig_xstate_ia32_size sig_xstate_size |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 29 | # define fx_sw_reserved_ia32 fx_sw_reserved |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 30 | # define user_i387_ia32_struct user_i387_struct |
| 31 | # define user32_fxsr_struct user_fxsr_struct |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 32 | #endif |
| 33 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 34 | #ifdef CONFIG_MATH_EMULATION |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 35 | # define HAVE_HWFP (boot_cpu_data.hard_math) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #else |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 37 | # define HAVE_HWFP 1 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #endif |
| 39 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 40 | static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 41 | unsigned int xstate_size; |
Suresh Siddha | 3c1c7f1 | 2008-07-29 10:29:21 -0700 | [diff] [blame] | 42 | unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32); |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 43 | static struct i387_fxsave_struct fx_scratch __cpuinitdata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 45 | void __cpuinit mxcsr_feature_mask_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | { |
| 47 | unsigned long mask = 0; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 48 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | clts(); |
| 50 | if (cpu_has_fxsr) { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 51 | memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct)); |
| 52 | asm volatile("fxsave %0" : : "m" (fx_scratch)); |
| 53 | mask = fx_scratch.mxcsr_mask; |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 54 | if (mask == 0) |
| 55 | mask = 0x0000ffbf; |
| 56 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | mxcsr_feature_mask &= mask; |
| 58 | stts(); |
| 59 | } |
| 60 | |
Rakib Mullick | 9bc646f | 2008-11-20 19:08:45 +0600 | [diff] [blame] | 61 | void __cpuinit init_thread_xstate(void) |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 62 | { |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 63 | if (!HAVE_HWFP) { |
| 64 | xstate_size = sizeof(struct i387_soft_struct); |
| 65 | return; |
| 66 | } |
| 67 | |
Suresh Siddha | dc1e35c | 2008-07-29 10:29:19 -0700 | [diff] [blame] | 68 | if (cpu_has_xsave) { |
| 69 | xsave_cntxt_init(); |
| 70 | return; |
| 71 | } |
| 72 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 73 | if (cpu_has_fxsr) |
| 74 | xstate_size = sizeof(struct i387_fxsave_struct); |
| 75 | #ifdef CONFIG_X86_32 |
| 76 | else |
| 77 | xstate_size = sizeof(struct i387_fsave_struct); |
| 78 | #endif |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 79 | } |
| 80 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 81 | #ifdef CONFIG_X86_64 |
| 82 | /* |
| 83 | * Called at bootup to set up the initial FPU state that is later cloned |
| 84 | * into all processes. |
| 85 | */ |
| 86 | void __cpuinit fpu_init(void) |
| 87 | { |
| 88 | unsigned long oldcr0 = read_cr0(); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 89 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 90 | set_in_cr4(X86_CR4_OSFXSR); |
| 91 | set_in_cr4(X86_CR4_OSXMMEXCPT); |
| 92 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 93 | write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */ |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 94 | |
Suresh Siddha | dc1e35c | 2008-07-29 10:29:19 -0700 | [diff] [blame] | 95 | /* |
| 96 | * Boot processor to setup the FP and extended state context info. |
| 97 | */ |
| 98 | if (!smp_processor_id()) |
| 99 | init_thread_xstate(); |
| 100 | xsave_init(); |
| 101 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 102 | mxcsr_feature_mask_init(); |
| 103 | /* clean state in init */ |
Suresh Siddha | b359e8a | 2008-07-29 10:29:20 -0700 | [diff] [blame] | 104 | if (cpu_has_xsave) |
| 105 | current_thread_info()->status = TS_XSAVE; |
| 106 | else |
| 107 | current_thread_info()->status = 0; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 108 | clear_used_math(); |
| 109 | } |
| 110 | #endif /* CONFIG_X86_64 */ |
| 111 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | /* |
| 113 | * The _current_ task is using the FPU for the first time |
| 114 | * so initialize it and set the mxcsr to its default |
| 115 | * value at reset if we support XMM instructions and then |
| 116 | * remeber the current task has used the FPU. |
| 117 | */ |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 118 | int init_fpu(struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 120 | if (tsk_used_math(tsk)) { |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 121 | if (HAVE_HWFP && tsk == current) |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 122 | unlazy_fpu(tsk); |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 123 | return 0; |
| 124 | } |
| 125 | |
| 126 | /* |
| 127 | * Memory allocation at the first usage of the FPU and other state. |
| 128 | */ |
| 129 | if (!tsk->thread.xstate) { |
| 130 | tsk->thread.xstate = kmem_cache_alloc(task_xstate_cachep, |
| 131 | GFP_KERNEL); |
| 132 | if (!tsk->thread.xstate) |
| 133 | return -ENOMEM; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 134 | } |
| 135 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 136 | #ifdef CONFIG_X86_32 |
| 137 | if (!HAVE_HWFP) { |
| 138 | memset(tsk->thread.xstate, 0, xstate_size); |
| 139 | finit(); |
| 140 | set_stopped_child_used_math(tsk); |
| 141 | return 0; |
| 142 | } |
| 143 | #endif |
| 144 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | if (cpu_has_fxsr) { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 146 | struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; |
| 147 | |
| 148 | memset(fx, 0, xstate_size); |
| 149 | fx->cwd = 0x37f; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | if (cpu_has_xmm) |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 151 | fx->mxcsr = MXCSR_DEFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | } else { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 153 | struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; |
| 154 | memset(fp, 0, xstate_size); |
| 155 | fp->cwd = 0xffff037fu; |
| 156 | fp->swd = 0xffff0000u; |
| 157 | fp->twd = 0xffffffffu; |
| 158 | fp->fos = 0xffff0000u; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 159 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 160 | /* |
| 161 | * Only the device not available exception or ptrace can call init_fpu. |
| 162 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | set_stopped_child_used_math(tsk); |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 164 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | } |
| 166 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 167 | int fpregs_active(struct task_struct *target, const struct user_regset *regset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 169 | return tsk_used_math(target) ? regset->n : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 170 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 171 | |
| 172 | int xfpregs_active(struct task_struct *target, const struct user_regset *regset) |
| 173 | { |
| 174 | return (cpu_has_fxsr && tsk_used_math(target)) ? regset->n : 0; |
| 175 | } |
| 176 | |
| 177 | int xfpregs_get(struct task_struct *target, const struct user_regset *regset, |
| 178 | unsigned int pos, unsigned int count, |
| 179 | void *kbuf, void __user *ubuf) |
| 180 | { |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 181 | int ret; |
| 182 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 183 | if (!cpu_has_fxsr) |
| 184 | return -ENODEV; |
| 185 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 186 | ret = init_fpu(target); |
| 187 | if (ret) |
| 188 | return ret; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 189 | |
| 190 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 191 | &target->thread.xstate->fxsave, 0, -1); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 192 | } |
| 193 | |
| 194 | int xfpregs_set(struct task_struct *target, const struct user_regset *regset, |
| 195 | unsigned int pos, unsigned int count, |
| 196 | const void *kbuf, const void __user *ubuf) |
| 197 | { |
| 198 | int ret; |
| 199 | |
| 200 | if (!cpu_has_fxsr) |
| 201 | return -ENODEV; |
| 202 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 203 | ret = init_fpu(target); |
| 204 | if (ret) |
| 205 | return ret; |
| 206 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 207 | set_stopped_child_used_math(target); |
| 208 | |
| 209 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 210 | &target->thread.xstate->fxsave, 0, -1); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 211 | |
| 212 | /* |
| 213 | * mxcsr reserved bits must be masked to zero for security reasons. |
| 214 | */ |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 215 | target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 216 | |
Suresh Siddha | 42deec6 | 2008-07-29 10:29:26 -0700 | [diff] [blame] | 217 | /* |
| 218 | * update the header bits in the xsave header, indicating the |
| 219 | * presence of FP and SSE state. |
| 220 | */ |
| 221 | if (cpu_has_xsave) |
| 222 | target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; |
| 223 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 224 | return ret; |
| 225 | } |
| 226 | |
| 227 | #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 229 | /* |
| 230 | * FPU tag word conversions. |
| 231 | */ |
| 232 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 233 | static inline unsigned short twd_i387_to_fxsr(unsigned short twd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | { |
| 235 | unsigned int tmp; /* to avoid 16 bit prefixes in the code */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 236 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | /* Transform each pair of bits into 01 (valid) or 00 (empty) */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 238 | tmp = ~twd; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 239 | tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 240 | /* and move the valid bits to the lower byte. */ |
| 241 | tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ |
| 242 | tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ |
| 243 | tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 244 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 245 | return tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | } |
| 247 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 248 | #define FPREG_ADDR(f, n) ((void *)&(f)->st_space + (n) * 16); |
| 249 | #define FP_EXP_TAG_VALID 0 |
| 250 | #define FP_EXP_TAG_ZERO 1 |
| 251 | #define FP_EXP_TAG_SPECIAL 2 |
| 252 | #define FP_EXP_TAG_EMPTY 3 |
| 253 | |
| 254 | static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 256 | struct _fpxreg *st; |
| 257 | u32 tos = (fxsave->swd >> 11) & 7; |
| 258 | u32 twd = (unsigned long) fxsave->twd; |
| 259 | u32 tag; |
| 260 | u32 ret = 0xffff0000u; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | int i; |
| 262 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 263 | for (i = 0; i < 8; i++, twd >>= 1) { |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 264 | if (twd & 0x1) { |
| 265 | st = FPREG_ADDR(fxsave, (i - tos) & 7); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 267 | switch (st->exponent & 0x7fff) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | case 0x7fff: |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 269 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | break; |
| 271 | case 0x0000: |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 272 | if (!st->significand[0] && |
| 273 | !st->significand[1] && |
| 274 | !st->significand[2] && |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 275 | !st->significand[3]) |
| 276 | tag = FP_EXP_TAG_ZERO; |
| 277 | else |
| 278 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | break; |
| 280 | default: |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 281 | if (st->significand[3] & 0x8000) |
| 282 | tag = FP_EXP_TAG_VALID; |
| 283 | else |
| 284 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | break; |
| 286 | } |
| 287 | } else { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 288 | tag = FP_EXP_TAG_EMPTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 290 | ret |= tag << (2 * i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | } |
| 292 | return ret; |
| 293 | } |
| 294 | |
| 295 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | * FXSR floating point environment conversions. |
| 297 | */ |
| 298 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 299 | static void |
| 300 | convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 302 | struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 303 | struct _fpreg *to = (struct _fpreg *) &env->st_space[0]; |
| 304 | struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | int i; |
| 306 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 307 | env->cwd = fxsave->cwd | 0xffff0000u; |
| 308 | env->swd = fxsave->swd | 0xffff0000u; |
| 309 | env->twd = twd_fxsr_to_i387(fxsave); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 311 | #ifdef CONFIG_X86_64 |
| 312 | env->fip = fxsave->rip; |
| 313 | env->foo = fxsave->rdp; |
| 314 | if (tsk == current) { |
| 315 | /* |
| 316 | * should be actually ds/cs at fpu exception time, but |
| 317 | * that information is not available in 64bit mode. |
| 318 | */ |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 319 | asm("mov %%ds, %[fos]" : [fos] "=r" (env->fos)); |
| 320 | asm("mov %%cs, %[fcs]" : [fcs] "=r" (env->fcs)); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 321 | } else { |
| 322 | struct pt_regs *regs = task_pt_regs(tsk); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 323 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 324 | env->fos = 0xffff0000 | tsk->thread.ds; |
| 325 | env->fcs = regs->cs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 327 | #else |
| 328 | env->fip = fxsave->fip; |
Jan Beulich | 609b529 | 2008-03-05 08:35:14 +0000 | [diff] [blame] | 329 | env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 330 | env->foo = fxsave->foo; |
| 331 | env->fos = fxsave->fos; |
| 332 | #endif |
| 333 | |
| 334 | for (i = 0; i < 8; ++i) |
| 335 | memcpy(&to[i], &from[i], sizeof(to[0])); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | } |
| 337 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 338 | static void convert_to_fxsr(struct task_struct *tsk, |
| 339 | const struct user_i387_ia32_struct *env) |
| 340 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 342 | struct i387_fxsave_struct *fxsave = &tsk->thread.xstate->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 343 | struct _fpreg *from = (struct _fpreg *) &env->st_space[0]; |
| 344 | struct _fpxreg *to = (struct _fpxreg *) &fxsave->st_space[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | int i; |
| 346 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 347 | fxsave->cwd = env->cwd; |
| 348 | fxsave->swd = env->swd; |
| 349 | fxsave->twd = twd_i387_to_fxsr(env->twd); |
| 350 | fxsave->fop = (u16) ((u32) env->fcs >> 16); |
| 351 | #ifdef CONFIG_X86_64 |
| 352 | fxsave->rip = env->fip; |
| 353 | fxsave->rdp = env->foo; |
| 354 | /* cs and ds ignored */ |
| 355 | #else |
| 356 | fxsave->fip = env->fip; |
| 357 | fxsave->fcs = (env->fcs & 0xffff); |
| 358 | fxsave->foo = env->foo; |
| 359 | fxsave->fos = env->fos; |
| 360 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 362 | for (i = 0; i < 8; ++i) |
| 363 | memcpy(&to[i], &from[i], sizeof(from[0])); |
| 364 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 366 | int fpregs_get(struct task_struct *target, const struct user_regset *regset, |
| 367 | unsigned int pos, unsigned int count, |
| 368 | void *kbuf, void __user *ubuf) |
| 369 | { |
| 370 | struct user_i387_ia32_struct env; |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 371 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 373 | ret = init_fpu(target); |
| 374 | if (ret) |
| 375 | return ret; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 376 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 377 | if (!HAVE_HWFP) |
| 378 | return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf); |
| 379 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 380 | if (!cpu_has_fxsr) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 381 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 382 | &target->thread.xstate->fsave, 0, |
| 383 | -1); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 384 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 385 | |
| 386 | if (kbuf && pos == 0 && count == sizeof(env)) { |
| 387 | convert_from_fxsr(kbuf, target); |
| 388 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 390 | |
| 391 | convert_from_fxsr(&env, target); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 392 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 393 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1); |
| 394 | } |
| 395 | |
| 396 | int fpregs_set(struct task_struct *target, const struct user_regset *regset, |
| 397 | unsigned int pos, unsigned int count, |
| 398 | const void *kbuf, const void __user *ubuf) |
| 399 | { |
| 400 | struct user_i387_ia32_struct env; |
| 401 | int ret; |
| 402 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 403 | ret = init_fpu(target); |
| 404 | if (ret) |
| 405 | return ret; |
| 406 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 407 | set_stopped_child_used_math(target); |
| 408 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 409 | if (!HAVE_HWFP) |
| 410 | return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf); |
| 411 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 412 | if (!cpu_has_fxsr) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 413 | return user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 414 | &target->thread.xstate->fsave, 0, -1); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 415 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 416 | |
| 417 | if (pos > 0 || count < sizeof(env)) |
| 418 | convert_from_fxsr(&env, target); |
| 419 | |
| 420 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &env, 0, -1); |
| 421 | if (!ret) |
| 422 | convert_to_fxsr(target, &env); |
| 423 | |
Suresh Siddha | 42deec6 | 2008-07-29 10:29:26 -0700 | [diff] [blame] | 424 | /* |
| 425 | * update the header bit in the xsave header, indicating the |
| 426 | * presence of FP. |
| 427 | */ |
| 428 | if (cpu_has_xsave) |
| 429 | target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FP; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 430 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 431 | } |
| 432 | |
| 433 | /* |
| 434 | * Signal frame handlers. |
| 435 | */ |
| 436 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 437 | static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | { |
| 439 | struct task_struct *tsk = current; |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 440 | struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 442 | fp->status = fp->swd; |
| 443 | if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 444 | return -1; |
| 445 | return 1; |
| 446 | } |
| 447 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 448 | static int save_i387_fxsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | { |
| 450 | struct task_struct *tsk = current; |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 451 | struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 452 | struct user_i387_ia32_struct env; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 453 | int err = 0; |
| 454 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 455 | convert_from_fxsr(&env, tsk); |
| 456 | if (__copy_to_user(buf, &env, sizeof(env))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | return -1; |
| 458 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 459 | err |= __put_user(fx->swd, &buf->status); |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 460 | err |= __put_user(X86_FXSR_MAGIC, &buf->magic); |
| 461 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | return -1; |
| 463 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 464 | if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | return -1; |
| 466 | return 1; |
| 467 | } |
| 468 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 469 | static int save_i387_xsave(void __user *buf) |
| 470 | { |
Suresh Siddha | 04944b7 | 2008-10-07 14:04:28 -0700 | [diff] [blame] | 471 | struct task_struct *tsk = current; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 472 | struct _fpstate_ia32 __user *fx = buf; |
| 473 | int err = 0; |
| 474 | |
Suresh Siddha | 04944b7 | 2008-10-07 14:04:28 -0700 | [diff] [blame] | 475 | /* |
| 476 | * For legacy compatible, we always set FP/SSE bits in the bit |
| 477 | * vector while saving the state to the user context. |
| 478 | * This will enable us capturing any changes(during sigreturn) to |
| 479 | * the FP/SSE bits by the legacy applications which don't touch |
| 480 | * xstate_bv in the xsave header. |
| 481 | * |
| 482 | * xsave aware applications can change the xstate_bv in the xsave |
| 483 | * header as well as change any contents in the memory layout. |
| 484 | * xrestore as part of sigreturn will capture all the changes. |
| 485 | */ |
| 486 | tsk->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; |
| 487 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 488 | if (save_i387_fxsave(fx) < 0) |
| 489 | return -1; |
| 490 | |
| 491 | err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32, |
| 492 | sizeof(struct _fpx_sw_bytes)); |
| 493 | err |= __put_user(FP_XSTATE_MAGIC2, |
| 494 | (__u32 __user *) (buf + sig_xstate_ia32_size |
| 495 | - FP_XSTATE_MAGIC2_SIZE)); |
| 496 | if (err) |
| 497 | return -1; |
| 498 | |
| 499 | return 1; |
| 500 | } |
| 501 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 502 | int save_i387_xstate_ia32(void __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 503 | { |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 504 | struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; |
| 505 | struct task_struct *tsk = current; |
| 506 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 507 | if (!used_math()) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 508 | return 0; |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 509 | |
| 510 | if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size)) |
| 511 | return -EACCES; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 512 | /* |
| 513 | * This will cause a "finit" to be triggered by the next |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 514 | * attempted FPU operation by the 'current' process. |
| 515 | */ |
| 516 | clear_used_math(); |
| 517 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 518 | if (!HAVE_HWFP) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 519 | return fpregs_soft_get(current, NULL, |
| 520 | 0, sizeof(struct user_i387_ia32_struct), |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 521 | NULL, fp) ? -1 : 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 522 | } |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 523 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 524 | unlazy_fpu(tsk); |
| 525 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 526 | if (cpu_has_xsave) |
| 527 | return save_i387_xsave(fp); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 528 | if (cpu_has_fxsr) |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 529 | return save_i387_fxsave(fp); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 530 | else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 531 | return save_i387_fsave(fp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 532 | } |
| 533 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 534 | static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | { |
| 536 | struct task_struct *tsk = current; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 537 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 538 | return __copy_from_user(&tsk->thread.xstate->fsave, buf, |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 539 | sizeof(struct i387_fsave_struct)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 540 | } |
| 541 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 542 | static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf, |
| 543 | unsigned int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 544 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | struct task_struct *tsk = current; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 546 | struct user_i387_ia32_struct env; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 547 | int err; |
| 548 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 549 | err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0], |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 550 | size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 551 | /* mxcsr reserved bits must be masked to zero for security reasons */ |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 552 | tsk->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 553 | if (err || __copy_from_user(&env, buf, sizeof(env))) |
| 554 | return 1; |
| 555 | convert_to_fxsr(tsk, &env); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 556 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 557 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 558 | } |
| 559 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 560 | static int restore_i387_xsave(void __user *buf) |
| 561 | { |
| 562 | struct _fpx_sw_bytes fx_sw_user; |
| 563 | struct _fpstate_ia32 __user *fx_user = |
| 564 | ((struct _fpstate_ia32 __user *) buf); |
| 565 | struct i387_fxsave_struct __user *fx = |
| 566 | (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0]; |
| 567 | struct xsave_hdr_struct *xsave_hdr = |
| 568 | ¤t->thread.xstate->xsave.xsave_hdr; |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 569 | u64 mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 570 | int err; |
| 571 | |
| 572 | if (check_for_xstate(fx, buf, &fx_sw_user)) |
| 573 | goto fx_only; |
| 574 | |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 575 | mask = fx_sw_user.xstate_bv; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 576 | |
| 577 | err = restore_i387_fxsave(buf, fx_sw_user.xstate_size); |
| 578 | |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 579 | xsave_hdr->xstate_bv &= pcntxt_mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 580 | /* |
| 581 | * These bits must be zero. |
| 582 | */ |
| 583 | xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0; |
| 584 | |
| 585 | /* |
| 586 | * Init the state that is not present in the memory layout |
| 587 | * and enabled by the OS. |
| 588 | */ |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 589 | mask = ~(pcntxt_mask & ~mask); |
| 590 | xsave_hdr->xstate_bv &= mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 591 | |
| 592 | return err; |
| 593 | fx_only: |
| 594 | /* |
| 595 | * Couldn't find the extended state information in the memory |
| 596 | * layout. Restore the FP/SSE and init the other extended state |
| 597 | * enabled by the OS. |
| 598 | */ |
| 599 | xsave_hdr->xstate_bv = XSTATE_FPSSE; |
| 600 | return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct)); |
| 601 | } |
| 602 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 603 | int restore_i387_xstate_ia32(void __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | { |
| 605 | int err; |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 606 | struct task_struct *tsk = current; |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 607 | struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 609 | if (HAVE_HWFP) |
Suresh Siddha | fd3c3ed | 2008-05-07 12:09:52 -0700 | [diff] [blame] | 610 | clear_fpu(tsk); |
| 611 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 612 | if (!buf) { |
| 613 | if (used_math()) { |
| 614 | clear_fpu(tsk); |
| 615 | clear_used_math(); |
| 616 | } |
| 617 | |
| 618 | return 0; |
| 619 | } else |
| 620 | if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size)) |
| 621 | return -EACCES; |
| 622 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 623 | if (!used_math()) { |
| 624 | err = init_fpu(tsk); |
| 625 | if (err) |
| 626 | return err; |
| 627 | } |
Suresh Siddha | fd3c3ed | 2008-05-07 12:09:52 -0700 | [diff] [blame] | 628 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 629 | if (HAVE_HWFP) { |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 630 | if (cpu_has_xsave) |
| 631 | err = restore_i387_xsave(buf); |
| 632 | else if (cpu_has_fxsr) |
| 633 | err = restore_i387_fxsave(fp, sizeof(struct |
| 634 | i387_fxsave_struct)); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 635 | else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 636 | err = restore_i387_fsave(fp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 637 | } else { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 638 | err = fpregs_soft_set(current, NULL, |
| 639 | 0, sizeof(struct user_i387_ia32_struct), |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 640 | NULL, fp) != 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | } |
| 642 | set_used_math(); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 643 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | return err; |
| 645 | } |
| 646 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | /* |
| 648 | * FPU state for core dumps. |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 649 | * This is only used for a.out dumps now. |
| 650 | * It is declared generically using elf_fpregset_t (which is |
| 651 | * struct user_i387_struct) but is in fact only used for 32-bit |
| 652 | * dumps, so on 64-bit it is really struct user_i387_ia32_struct. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 654 | int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | struct task_struct *tsk = current; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 657 | int fpvalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 658 | |
| 659 | fpvalid = !!used_math(); |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 660 | if (fpvalid) |
| 661 | fpvalid = !fpregs_get(tsk, NULL, |
| 662 | 0, sizeof(struct user_i387_ia32_struct), |
| 663 | fpu, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | |
| 665 | return fpvalid; |
| 666 | } |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 667 | EXPORT_SYMBOL(dump_fpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 669 | #endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */ |