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> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 11 | #include <linux/slab.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 12 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <asm/sigcontext.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 14 | #include <asm/processor.h> |
| 15 | #include <asm/math_emu.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <asm/uaccess.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 17 | #include <asm/ptrace.h> |
| 18 | #include <asm/i387.h> |
Linus Torvalds | 1361b83 | 2012-02-21 13:19:22 -0800 | [diff] [blame] | 19 | #include <asm/fpu-internal.h> |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 20 | #include <asm/user.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 22 | #ifdef CONFIG_X86_64 |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 23 | # include <asm/sigcontext32.h> |
| 24 | # include <asm/user32.h> |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 25 | #else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 26 | # define save_i387_xstate_ia32 save_i387_xstate |
| 27 | # define restore_i387_xstate_ia32 restore_i387_xstate |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 28 | # define _fpstate_ia32 _fpstate |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 29 | # define _xstate_ia32 _xstate |
Suresh Siddha | 3c1c7f1 | 2008-07-29 10:29:21 -0700 | [diff] [blame] | 30 | # define sig_xstate_ia32_size sig_xstate_size |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 31 | # define fx_sw_reserved_ia32 fx_sw_reserved |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 32 | # define user_i387_ia32_struct user_i387_struct |
| 33 | # define user32_fxsr_struct user_fxsr_struct |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 34 | #endif |
| 35 | |
Linus Torvalds | 8546c00 | 2012-02-21 10:25:45 -0800 | [diff] [blame] | 36 | /* |
| 37 | * Were we in an interrupt that interrupted kernel mode? |
| 38 | * |
| 39 | * We can do a kernel_fpu_begin/end() pair *ONLY* if that |
| 40 | * pair does nothing at all: the thread must not have fpu (so |
| 41 | * that we don't try to save the FPU state), and TS must |
| 42 | * be set (so that the clts/stts pair does nothing that is |
| 43 | * visible in the interrupted kernel thread). |
| 44 | */ |
| 45 | static inline bool interrupted_kernel_fpu_idle(void) |
| 46 | { |
| 47 | return !__thread_has_fpu(current) && |
| 48 | (read_cr0() & X86_CR0_TS); |
| 49 | } |
| 50 | |
| 51 | /* |
| 52 | * Were we in user mode (or vm86 mode) when we were |
| 53 | * interrupted? |
| 54 | * |
| 55 | * Doing kernel_fpu_begin/end() is ok if we are running |
| 56 | * in an interrupt context from user mode - we'll just |
| 57 | * save the FPU state as required. |
| 58 | */ |
| 59 | static inline bool interrupted_user_mode(void) |
| 60 | { |
| 61 | struct pt_regs *regs = get_irq_regs(); |
| 62 | return regs && user_mode_vm(regs); |
| 63 | } |
| 64 | |
| 65 | /* |
| 66 | * Can we use the FPU in kernel mode with the |
| 67 | * whole "kernel_fpu_begin/end()" sequence? |
| 68 | * |
| 69 | * It's always ok in process context (ie "not interrupt") |
| 70 | * but it is sometimes ok even from an irq. |
| 71 | */ |
| 72 | bool irq_fpu_usable(void) |
| 73 | { |
| 74 | return !in_interrupt() || |
| 75 | interrupted_user_mode() || |
| 76 | interrupted_kernel_fpu_idle(); |
| 77 | } |
| 78 | EXPORT_SYMBOL(irq_fpu_usable); |
| 79 | |
| 80 | void kernel_fpu_begin(void) |
| 81 | { |
| 82 | struct task_struct *me = current; |
| 83 | |
| 84 | WARN_ON_ONCE(!irq_fpu_usable()); |
| 85 | preempt_disable(); |
| 86 | if (__thread_has_fpu(me)) { |
| 87 | __save_init_fpu(me); |
| 88 | __thread_clear_has_fpu(me); |
| 89 | /* We do 'stts()' in kernel_fpu_end() */ |
| 90 | } else { |
Alex Shi | c6ae41e | 2012-05-11 15:35:27 +0800 | [diff] [blame] | 91 | this_cpu_write(fpu_owner_task, NULL); |
Linus Torvalds | 8546c00 | 2012-02-21 10:25:45 -0800 | [diff] [blame] | 92 | clts(); |
| 93 | } |
| 94 | } |
| 95 | EXPORT_SYMBOL(kernel_fpu_begin); |
| 96 | |
| 97 | void kernel_fpu_end(void) |
| 98 | { |
| 99 | stts(); |
| 100 | preempt_enable(); |
| 101 | } |
| 102 | EXPORT_SYMBOL(kernel_fpu_end); |
| 103 | |
| 104 | void unlazy_fpu(struct task_struct *tsk) |
| 105 | { |
| 106 | preempt_disable(); |
| 107 | if (__thread_has_fpu(tsk)) { |
| 108 | __save_init_fpu(tsk); |
| 109 | __thread_fpu_end(tsk); |
| 110 | } else |
| 111 | tsk->fpu_counter = 0; |
| 112 | preempt_enable(); |
| 113 | } |
| 114 | EXPORT_SYMBOL(unlazy_fpu); |
| 115 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | #ifdef CONFIG_MATH_EMULATION |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 117 | # define HAVE_HWFP (boot_cpu_data.hard_math) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | #else |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 119 | # define HAVE_HWFP 1 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | #endif |
| 121 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 122 | static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu; |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 123 | unsigned int xstate_size; |
Xiaotian Feng | f45755b | 2010-08-13 15:19:11 +0800 | [diff] [blame] | 124 | EXPORT_SYMBOL_GPL(xstate_size); |
Suresh Siddha | 3c1c7f1 | 2008-07-29 10:29:21 -0700 | [diff] [blame] | 125 | unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32); |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 126 | static struct i387_fxsave_struct fx_scratch __cpuinitdata; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | |
Linus Torvalds | 1361b83 | 2012-02-21 13:19:22 -0800 | [diff] [blame] | 128 | static void __cpuinit mxcsr_feature_mask_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 129 | { |
| 130 | unsigned long mask = 0; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 131 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | clts(); |
| 133 | if (cpu_has_fxsr) { |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 134 | memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct)); |
| 135 | asm volatile("fxsave %0" : : "m" (fx_scratch)); |
| 136 | mask = fx_scratch.mxcsr_mask; |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 137 | if (mask == 0) |
| 138 | mask = 0x0000ffbf; |
| 139 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | mxcsr_feature_mask &= mask; |
| 141 | stts(); |
| 142 | } |
| 143 | |
Robert Richter | 0e49bf6 | 2010-07-21 19:03:52 +0200 | [diff] [blame] | 144 | static void __cpuinit init_thread_xstate(void) |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 145 | { |
Robert Richter | 0e49bf6 | 2010-07-21 19:03:52 +0200 | [diff] [blame] | 146 | /* |
| 147 | * Note that xstate_size might be overwriten later during |
| 148 | * xsave_init(). |
| 149 | */ |
| 150 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 151 | if (!HAVE_HWFP) { |
Robert Richter | 1f999ab | 2010-07-21 19:03:57 +0200 | [diff] [blame] | 152 | /* |
| 153 | * Disable xsave as we do not support it if i387 |
| 154 | * emulation is enabled. |
| 155 | */ |
| 156 | setup_clear_cpu_cap(X86_FEATURE_XSAVE); |
| 157 | setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 158 | xstate_size = sizeof(struct i387_soft_struct); |
| 159 | return; |
| 160 | } |
| 161 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 162 | if (cpu_has_fxsr) |
| 163 | xstate_size = sizeof(struct i387_fxsave_struct); |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 164 | else |
| 165 | xstate_size = sizeof(struct i387_fsave_struct); |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 166 | } |
| 167 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 168 | /* |
| 169 | * Called at bootup to set up the initial FPU state that is later cloned |
| 170 | * into all processes. |
| 171 | */ |
Robert Richter | 0e49bf6 | 2010-07-21 19:03:52 +0200 | [diff] [blame] | 172 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 173 | void __cpuinit fpu_init(void) |
| 174 | { |
Brian Gerst | 6ac8bac | 2010-09-03 21:17:09 -0400 | [diff] [blame] | 175 | unsigned long cr0; |
| 176 | unsigned long cr4_mask = 0; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 177 | |
Brian Gerst | 6ac8bac | 2010-09-03 21:17:09 -0400 | [diff] [blame] | 178 | if (cpu_has_fxsr) |
| 179 | cr4_mask |= X86_CR4_OSFXSR; |
| 180 | if (cpu_has_xmm) |
| 181 | cr4_mask |= X86_CR4_OSXMMEXCPT; |
| 182 | if (cr4_mask) |
| 183 | set_in_cr4(cr4_mask); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 184 | |
Brian Gerst | 6ac8bac | 2010-09-03 21:17:09 -0400 | [diff] [blame] | 185 | cr0 = read_cr0(); |
| 186 | cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */ |
| 187 | if (!HAVE_HWFP) |
| 188 | cr0 |= X86_CR0_EM; |
| 189 | write_cr0(cr0); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 190 | |
Suresh Siddha | dc1e35c | 2008-07-29 10:29:19 -0700 | [diff] [blame] | 191 | if (!smp_processor_id()) |
| 192 | init_thread_xstate(); |
Suresh Siddha | dc1e35c | 2008-07-29 10:29:19 -0700 | [diff] [blame] | 193 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 194 | mxcsr_feature_mask_init(); |
| 195 | /* clean state in init */ |
Avi Kivity | c9ad488 | 2010-05-06 11:45:45 +0300 | [diff] [blame] | 196 | current_thread_info()->status = 0; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 197 | clear_used_math(); |
| 198 | } |
Robert Richter | 0e49bf6 | 2010-07-21 19:03:52 +0200 | [diff] [blame] | 199 | |
Sheng Yang | 5ee481d | 2010-05-17 17:22:23 +0800 | [diff] [blame] | 200 | void fpu_finit(struct fpu *fpu) |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 201 | { |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 202 | if (!HAVE_HWFP) { |
| 203 | finit_soft_fpu(&fpu->state->soft); |
| 204 | return; |
| 205 | } |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 206 | |
| 207 | if (cpu_has_fxsr) { |
| 208 | struct i387_fxsave_struct *fx = &fpu->state->fxsave; |
| 209 | |
| 210 | memset(fx, 0, xstate_size); |
| 211 | fx->cwd = 0x37f; |
| 212 | if (cpu_has_xmm) |
| 213 | fx->mxcsr = MXCSR_DEFAULT; |
| 214 | } else { |
| 215 | struct i387_fsave_struct *fp = &fpu->state->fsave; |
| 216 | memset(fp, 0, xstate_size); |
| 217 | fp->cwd = 0xffff037fu; |
| 218 | fp->swd = 0xffff0000u; |
| 219 | fp->twd = 0xffffffffu; |
| 220 | fp->fos = 0xffff0000u; |
| 221 | } |
| 222 | } |
Sheng Yang | 5ee481d | 2010-05-17 17:22:23 +0800 | [diff] [blame] | 223 | EXPORT_SYMBOL_GPL(fpu_finit); |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 224 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | /* |
| 226 | * The _current_ task is using the FPU for the first time |
| 227 | * so initialize it and set the mxcsr to its default |
| 228 | * value at reset if we support XMM instructions and then |
Lucas De Marchi | 0d2eb44 | 2011-03-17 16:24:16 -0300 | [diff] [blame] | 229 | * remember the current task has used the FPU. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | */ |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 231 | int init_fpu(struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | { |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 233 | int ret; |
| 234 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 235 | if (tsk_used_math(tsk)) { |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 236 | if (HAVE_HWFP && tsk == current) |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 237 | unlazy_fpu(tsk); |
Oleg Nesterov | 089f9fb | 2012-04-16 22:48:15 +0200 | [diff] [blame] | 238 | tsk->thread.fpu.last_cpu = ~0; |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 239 | return 0; |
| 240 | } |
| 241 | |
| 242 | /* |
| 243 | * Memory allocation at the first usage of the FPU and other state. |
| 244 | */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 245 | ret = fpu_alloc(&tsk->thread.fpu); |
| 246 | if (ret) |
| 247 | return ret; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 248 | |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 249 | fpu_finit(&tsk->thread.fpu); |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 250 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | set_stopped_child_used_math(tsk); |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 252 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | } |
Avi Kivity | e5c3014 | 2011-01-11 12:15:54 +0200 | [diff] [blame] | 254 | EXPORT_SYMBOL_GPL(init_fpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 256 | /* |
| 257 | * The xstateregs_active() routine is the same as the fpregs_active() routine, |
| 258 | * as the "regset->n" for the xstate regset will be updated based on the feature |
| 259 | * capabilites supported by the xsave. |
| 260 | */ |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 261 | int fpregs_active(struct task_struct *target, const struct user_regset *regset) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 263 | return tsk_used_math(target) ? regset->n : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 265 | |
| 266 | int xfpregs_active(struct task_struct *target, const struct user_regset *regset) |
| 267 | { |
| 268 | return (cpu_has_fxsr && tsk_used_math(target)) ? regset->n : 0; |
| 269 | } |
| 270 | |
| 271 | int xfpregs_get(struct task_struct *target, const struct user_regset *regset, |
| 272 | unsigned int pos, unsigned int count, |
| 273 | void *kbuf, void __user *ubuf) |
| 274 | { |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 275 | int ret; |
| 276 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 277 | if (!cpu_has_fxsr) |
| 278 | return -ENODEV; |
| 279 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 280 | ret = init_fpu(target); |
| 281 | if (ret) |
| 282 | return ret; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 283 | |
Suresh Siddha | 29104e1 | 2010-07-19 16:05:49 -0700 | [diff] [blame] | 284 | sanitize_i387_state(target); |
| 285 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 286 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 287 | &target->thread.fpu.state->fxsave, 0, -1); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 288 | } |
| 289 | |
| 290 | int xfpregs_set(struct task_struct *target, const struct user_regset *regset, |
| 291 | unsigned int pos, unsigned int count, |
| 292 | const void *kbuf, const void __user *ubuf) |
| 293 | { |
| 294 | int ret; |
| 295 | |
| 296 | if (!cpu_has_fxsr) |
| 297 | return -ENODEV; |
| 298 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 299 | ret = init_fpu(target); |
| 300 | if (ret) |
| 301 | return ret; |
| 302 | |
Suresh Siddha | 29104e1 | 2010-07-19 16:05:49 -0700 | [diff] [blame] | 303 | sanitize_i387_state(target); |
| 304 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 305 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 306 | &target->thread.fpu.state->fxsave, 0, -1); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 307 | |
| 308 | /* |
| 309 | * mxcsr reserved bits must be masked to zero for security reasons. |
| 310 | */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 311 | target->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 312 | |
Suresh Siddha | 42deec6 | 2008-07-29 10:29:26 -0700 | [diff] [blame] | 313 | /* |
| 314 | * update the header bits in the xsave header, indicating the |
| 315 | * presence of FP and SSE state. |
| 316 | */ |
| 317 | if (cpu_has_xsave) |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 318 | target->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; |
Suresh Siddha | 42deec6 | 2008-07-29 10:29:26 -0700 | [diff] [blame] | 319 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 320 | return ret; |
| 321 | } |
| 322 | |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 323 | int xstateregs_get(struct task_struct *target, const struct user_regset *regset, |
| 324 | unsigned int pos, unsigned int count, |
| 325 | void *kbuf, void __user *ubuf) |
| 326 | { |
| 327 | int ret; |
| 328 | |
| 329 | if (!cpu_has_xsave) |
| 330 | return -ENODEV; |
| 331 | |
| 332 | ret = init_fpu(target); |
| 333 | if (ret) |
| 334 | return ret; |
| 335 | |
| 336 | /* |
Suresh Siddha | ff7fbc7 | 2010-02-22 14:51:33 -0800 | [diff] [blame] | 337 | * Copy the 48bytes defined by the software first into the xstate |
| 338 | * memory layout in the thread struct, so that we can copy the entire |
| 339 | * xstateregs to the user using one user_regset_copyout(). |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 340 | */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 341 | memcpy(&target->thread.fpu.state->fxsave.sw_reserved, |
Suresh Siddha | ff7fbc7 | 2010-02-22 14:51:33 -0800 | [diff] [blame] | 342 | xstate_fx_sw_bytes, sizeof(xstate_fx_sw_bytes)); |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 343 | |
| 344 | /* |
Suresh Siddha | ff7fbc7 | 2010-02-22 14:51:33 -0800 | [diff] [blame] | 345 | * Copy the xstate memory layout. |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 346 | */ |
| 347 | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 348 | &target->thread.fpu.state->xsave, 0, -1); |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 349 | return ret; |
| 350 | } |
| 351 | |
| 352 | int xstateregs_set(struct task_struct *target, const struct user_regset *regset, |
| 353 | unsigned int pos, unsigned int count, |
| 354 | const void *kbuf, const void __user *ubuf) |
| 355 | { |
| 356 | int ret; |
| 357 | struct xsave_hdr_struct *xsave_hdr; |
| 358 | |
| 359 | if (!cpu_has_xsave) |
| 360 | return -ENODEV; |
| 361 | |
| 362 | ret = init_fpu(target); |
| 363 | if (ret) |
| 364 | return ret; |
| 365 | |
| 366 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 367 | &target->thread.fpu.state->xsave, 0, -1); |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 368 | |
| 369 | /* |
| 370 | * mxcsr reserved bits must be masked to zero for security reasons. |
| 371 | */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 372 | target->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 373 | |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 374 | xsave_hdr = &target->thread.fpu.state->xsave.xsave_hdr; |
Suresh Siddha | 5b3efd5 | 2010-02-11 11:50:59 -0800 | [diff] [blame] | 375 | |
| 376 | xsave_hdr->xstate_bv &= pcntxt_mask; |
| 377 | /* |
| 378 | * These bits must be zero. |
| 379 | */ |
| 380 | xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0; |
| 381 | |
| 382 | return ret; |
| 383 | } |
| 384 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 385 | #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 387 | /* |
| 388 | * FPU tag word conversions. |
| 389 | */ |
| 390 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 391 | static inline unsigned short twd_i387_to_fxsr(unsigned short twd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | { |
| 393 | unsigned int tmp; /* to avoid 16 bit prefixes in the code */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 394 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | /* Transform each pair of bits into 01 (valid) or 00 (empty) */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 396 | tmp = ~twd; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 397 | tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 398 | /* and move the valid bits to the lower byte. */ |
| 399 | tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ |
| 400 | tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ |
| 401 | tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 402 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 403 | return tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | } |
| 405 | |
Phil Carmody | 497888c | 2011-07-14 15:07:13 +0300 | [diff] [blame] | 406 | #define FPREG_ADDR(f, n) ((void *)&(f)->st_space + (n) * 16) |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 407 | #define FP_EXP_TAG_VALID 0 |
| 408 | #define FP_EXP_TAG_ZERO 1 |
| 409 | #define FP_EXP_TAG_SPECIAL 2 |
| 410 | #define FP_EXP_TAG_EMPTY 3 |
| 411 | |
| 412 | static inline u32 twd_fxsr_to_i387(struct i387_fxsave_struct *fxsave) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 414 | struct _fpxreg *st; |
| 415 | u32 tos = (fxsave->swd >> 11) & 7; |
| 416 | u32 twd = (unsigned long) fxsave->twd; |
| 417 | u32 tag; |
| 418 | u32 ret = 0xffff0000u; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | int i; |
| 420 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 421 | for (i = 0; i < 8; i++, twd >>= 1) { |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 422 | if (twd & 0x1) { |
| 423 | st = FPREG_ADDR(fxsave, (i - tos) & 7); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 425 | switch (st->exponent & 0x7fff) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 426 | case 0x7fff: |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 427 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | break; |
| 429 | case 0x0000: |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 430 | if (!st->significand[0] && |
| 431 | !st->significand[1] && |
| 432 | !st->significand[2] && |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 433 | !st->significand[3]) |
| 434 | tag = FP_EXP_TAG_ZERO; |
| 435 | else |
| 436 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | break; |
| 438 | default: |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 439 | if (st->significand[3] & 0x8000) |
| 440 | tag = FP_EXP_TAG_VALID; |
| 441 | else |
| 442 | tag = FP_EXP_TAG_SPECIAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | break; |
| 444 | } |
| 445 | } else { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 446 | tag = FP_EXP_TAG_EMPTY; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 447 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 448 | ret |= tag << (2 * i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | } |
| 450 | return ret; |
| 451 | } |
| 452 | |
| 453 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | * FXSR floating point environment conversions. |
| 455 | */ |
| 456 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 457 | static void |
| 458 | 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] | 459 | { |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 460 | struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 461 | struct _fpreg *to = (struct _fpreg *) &env->st_space[0]; |
| 462 | struct _fpxreg *from = (struct _fpxreg *) &fxsave->st_space[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | int i; |
| 464 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 465 | env->cwd = fxsave->cwd | 0xffff0000u; |
| 466 | env->swd = fxsave->swd | 0xffff0000u; |
| 467 | env->twd = twd_fxsr_to_i387(fxsave); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 469 | #ifdef CONFIG_X86_64 |
| 470 | env->fip = fxsave->rip; |
| 471 | env->foo = fxsave->rdp; |
Brian Gerst | 10c11f3 | 2010-09-03 21:17:13 -0400 | [diff] [blame] | 472 | /* |
| 473 | * should be actually ds/cs at fpu exception time, but |
| 474 | * that information is not available in 64bit mode. |
| 475 | */ |
| 476 | env->fcs = task_pt_regs(tsk)->cs; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 477 | if (tsk == current) { |
Brian Gerst | 10c11f3 | 2010-09-03 21:17:13 -0400 | [diff] [blame] | 478 | savesegment(ds, env->fos); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 479 | } else { |
Brian Gerst | 10c11f3 | 2010-09-03 21:17:13 -0400 | [diff] [blame] | 480 | env->fos = tsk->thread.ds; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 481 | } |
Brian Gerst | 10c11f3 | 2010-09-03 21:17:13 -0400 | [diff] [blame] | 482 | env->fos |= 0xffff0000; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 483 | #else |
| 484 | env->fip = fxsave->fip; |
Jan Beulich | 609b529 | 2008-03-05 08:35:14 +0000 | [diff] [blame] | 485 | env->fcs = (u16) fxsave->fcs | ((u32) fxsave->fop << 16); |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 486 | env->foo = fxsave->foo; |
| 487 | env->fos = fxsave->fos; |
| 488 | #endif |
| 489 | |
| 490 | for (i = 0; i < 8; ++i) |
| 491 | memcpy(&to[i], &from[i], sizeof(to[0])); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 492 | } |
| 493 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 494 | static void convert_to_fxsr(struct task_struct *tsk, |
| 495 | const struct user_i387_ia32_struct *env) |
| 496 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 497 | { |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 498 | struct i387_fxsave_struct *fxsave = &tsk->thread.fpu.state->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 499 | struct _fpreg *from = (struct _fpreg *) &env->st_space[0]; |
| 500 | struct _fpxreg *to = (struct _fpxreg *) &fxsave->st_space[0]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | int i; |
| 502 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 503 | fxsave->cwd = env->cwd; |
| 504 | fxsave->swd = env->swd; |
| 505 | fxsave->twd = twd_i387_to_fxsr(env->twd); |
| 506 | fxsave->fop = (u16) ((u32) env->fcs >> 16); |
| 507 | #ifdef CONFIG_X86_64 |
| 508 | fxsave->rip = env->fip; |
| 509 | fxsave->rdp = env->foo; |
| 510 | /* cs and ds ignored */ |
| 511 | #else |
| 512 | fxsave->fip = env->fip; |
| 513 | fxsave->fcs = (env->fcs & 0xffff); |
| 514 | fxsave->foo = env->foo; |
| 515 | fxsave->fos = env->fos; |
| 516 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 518 | for (i = 0; i < 8; ++i) |
| 519 | memcpy(&to[i], &from[i], sizeof(from[0])); |
| 520 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 522 | int fpregs_get(struct task_struct *target, const struct user_regset *regset, |
| 523 | unsigned int pos, unsigned int count, |
| 524 | void *kbuf, void __user *ubuf) |
| 525 | { |
| 526 | struct user_i387_ia32_struct env; |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 527 | int ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 529 | ret = init_fpu(target); |
| 530 | if (ret) |
| 531 | return ret; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 532 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 533 | if (!HAVE_HWFP) |
| 534 | return fpregs_soft_get(target, regset, pos, count, kbuf, ubuf); |
| 535 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 536 | if (!cpu_has_fxsr) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 537 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 538 | &target->thread.fpu.state->fsave, 0, |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 539 | -1); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 540 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 541 | |
Suresh Siddha | 29104e1 | 2010-07-19 16:05:49 -0700 | [diff] [blame] | 542 | sanitize_i387_state(target); |
| 543 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 544 | if (kbuf && pos == 0 && count == sizeof(env)) { |
| 545 | convert_from_fxsr(kbuf, target); |
| 546 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 547 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 548 | |
| 549 | convert_from_fxsr(&env, target); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 550 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 551 | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &env, 0, -1); |
| 552 | } |
| 553 | |
| 554 | int fpregs_set(struct task_struct *target, const struct user_regset *regset, |
| 555 | unsigned int pos, unsigned int count, |
| 556 | const void *kbuf, const void __user *ubuf) |
| 557 | { |
| 558 | struct user_i387_ia32_struct env; |
| 559 | int ret; |
| 560 | |
Suresh Siddha | aa283f4 | 2008-03-10 15:28:05 -0700 | [diff] [blame] | 561 | ret = init_fpu(target); |
| 562 | if (ret) |
| 563 | return ret; |
| 564 | |
Suresh Siddha | 29104e1 | 2010-07-19 16:05:49 -0700 | [diff] [blame] | 565 | sanitize_i387_state(target); |
| 566 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 567 | if (!HAVE_HWFP) |
| 568 | return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf); |
| 569 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 570 | if (!cpu_has_fxsr) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 571 | return user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 572 | &target->thread.fpu.state->fsave, 0, -1); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 573 | } |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 574 | |
| 575 | if (pos > 0 || count < sizeof(env)) |
| 576 | convert_from_fxsr(&env, target); |
| 577 | |
| 578 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &env, 0, -1); |
| 579 | if (!ret) |
| 580 | convert_to_fxsr(target, &env); |
| 581 | |
Suresh Siddha | 42deec6 | 2008-07-29 10:29:26 -0700 | [diff] [blame] | 582 | /* |
| 583 | * update the header bit in the xsave header, indicating the |
| 584 | * presence of FP. |
| 585 | */ |
| 586 | if (cpu_has_xsave) |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 587 | target->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FP; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 588 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | } |
| 590 | |
| 591 | /* |
| 592 | * Signal frame handlers. |
| 593 | */ |
| 594 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 595 | static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | { |
| 597 | struct task_struct *tsk = current; |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 598 | struct i387_fsave_struct *fp = &tsk->thread.fpu.state->fsave; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 600 | fp->status = fp->swd; |
| 601 | if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 602 | return -1; |
| 603 | return 1; |
| 604 | } |
| 605 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 606 | static int save_i387_fxsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | { |
| 608 | struct task_struct *tsk = current; |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 609 | struct i387_fxsave_struct *fx = &tsk->thread.fpu.state->fxsave; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 610 | struct user_i387_ia32_struct env; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | int err = 0; |
| 612 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 613 | convert_from_fxsr(&env, tsk); |
| 614 | if (__copy_to_user(buf, &env, sizeof(env))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | return -1; |
| 616 | |
Suresh Siddha | 61c4628 | 2008-03-10 15:28:04 -0700 | [diff] [blame] | 617 | err |= __put_user(fx->swd, &buf->status); |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 618 | err |= __put_user(X86_FXSR_MAGIC, &buf->magic); |
| 619 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | return -1; |
| 621 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 622 | if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 623 | return -1; |
| 624 | return 1; |
| 625 | } |
| 626 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 627 | static int save_i387_xsave(void __user *buf) |
| 628 | { |
Suresh Siddha | 04944b7 | 2008-10-07 14:04:28 -0700 | [diff] [blame] | 629 | struct task_struct *tsk = current; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 630 | struct _fpstate_ia32 __user *fx = buf; |
| 631 | int err = 0; |
| 632 | |
Suresh Siddha | 29104e1 | 2010-07-19 16:05:49 -0700 | [diff] [blame] | 633 | |
| 634 | sanitize_i387_state(tsk); |
| 635 | |
Suresh Siddha | 04944b7 | 2008-10-07 14:04:28 -0700 | [diff] [blame] | 636 | /* |
| 637 | * For legacy compatible, we always set FP/SSE bits in the bit |
| 638 | * vector while saving the state to the user context. |
| 639 | * This will enable us capturing any changes(during sigreturn) to |
| 640 | * the FP/SSE bits by the legacy applications which don't touch |
| 641 | * xstate_bv in the xsave header. |
| 642 | * |
| 643 | * xsave aware applications can change the xstate_bv in the xsave |
| 644 | * header as well as change any contents in the memory layout. |
| 645 | * xrestore as part of sigreturn will capture all the changes. |
| 646 | */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 647 | tsk->thread.fpu.state->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE; |
Suresh Siddha | 04944b7 | 2008-10-07 14:04:28 -0700 | [diff] [blame] | 648 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 649 | if (save_i387_fxsave(fx) < 0) |
| 650 | return -1; |
| 651 | |
| 652 | err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32, |
| 653 | sizeof(struct _fpx_sw_bytes)); |
| 654 | err |= __put_user(FP_XSTATE_MAGIC2, |
| 655 | (__u32 __user *) (buf + sig_xstate_ia32_size |
| 656 | - FP_XSTATE_MAGIC2_SIZE)); |
| 657 | if (err) |
| 658 | return -1; |
| 659 | |
| 660 | return 1; |
| 661 | } |
| 662 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 663 | int save_i387_xstate_ia32(void __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | { |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 665 | struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; |
| 666 | struct task_struct *tsk = current; |
| 667 | |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 668 | if (!used_math()) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | return 0; |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 670 | |
| 671 | if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size)) |
| 672 | return -EACCES; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 673 | /* |
| 674 | * This will cause a "finit" to be triggered by the next |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | * attempted FPU operation by the 'current' process. |
| 676 | */ |
| 677 | clear_used_math(); |
| 678 | |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 679 | if (!HAVE_HWFP) { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 680 | return fpregs_soft_get(current, NULL, |
| 681 | 0, sizeof(struct user_i387_ia32_struct), |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 682 | NULL, fp) ? -1 : 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | } |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 684 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 685 | unlazy_fpu(tsk); |
| 686 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 687 | if (cpu_has_xsave) |
| 688 | return save_i387_xsave(fp); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 689 | if (cpu_has_fxsr) |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 690 | return save_i387_fxsave(fp); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 691 | else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 692 | return save_i387_fsave(fp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 693 | } |
| 694 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 695 | static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 696 | { |
| 697 | struct task_struct *tsk = current; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 698 | |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 699 | return __copy_from_user(&tsk->thread.fpu.state->fsave, buf, |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 700 | sizeof(struct i387_fsave_struct)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | } |
| 702 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 703 | static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf, |
| 704 | unsigned int size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | struct task_struct *tsk = current; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 707 | struct user_i387_ia32_struct env; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 708 | int err; |
| 709 | |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 710 | err = __copy_from_user(&tsk->thread.fpu.state->fxsave, &buf->_fxsr_env[0], |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 711 | size); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | /* mxcsr reserved bits must be masked to zero for security reasons */ |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 713 | tsk->thread.fpu.state->fxsave.mxcsr &= mxcsr_feature_mask; |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 714 | if (err || __copy_from_user(&env, buf, sizeof(env))) |
| 715 | return 1; |
| 716 | convert_to_fxsr(tsk, &env); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 717 | |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 718 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 719 | } |
| 720 | |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 721 | static int restore_i387_xsave(void __user *buf) |
| 722 | { |
| 723 | struct _fpx_sw_bytes fx_sw_user; |
| 724 | struct _fpstate_ia32 __user *fx_user = |
| 725 | ((struct _fpstate_ia32 __user *) buf); |
| 726 | struct i387_fxsave_struct __user *fx = |
| 727 | (struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0]; |
| 728 | struct xsave_hdr_struct *xsave_hdr = |
Avi Kivity | 8660328 | 2010-05-06 11:45:46 +0300 | [diff] [blame] | 729 | ¤t->thread.fpu.state->xsave.xsave_hdr; |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 730 | u64 mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 731 | int err; |
| 732 | |
| 733 | if (check_for_xstate(fx, buf, &fx_sw_user)) |
| 734 | goto fx_only; |
| 735 | |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 736 | mask = fx_sw_user.xstate_bv; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 737 | |
| 738 | err = restore_i387_fxsave(buf, fx_sw_user.xstate_size); |
| 739 | |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 740 | xsave_hdr->xstate_bv &= pcntxt_mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 741 | /* |
| 742 | * These bits must be zero. |
| 743 | */ |
| 744 | xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0; |
| 745 | |
| 746 | /* |
| 747 | * Init the state that is not present in the memory layout |
| 748 | * and enabled by the OS. |
| 749 | */ |
H. Peter Anvin | 6152e4b | 2008-07-29 17:23:16 -0700 | [diff] [blame] | 750 | mask = ~(pcntxt_mask & ~mask); |
| 751 | xsave_hdr->xstate_bv &= mask; |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 752 | |
| 753 | return err; |
| 754 | fx_only: |
| 755 | /* |
| 756 | * Couldn't find the extended state information in the memory |
| 757 | * layout. Restore the FP/SSE and init the other extended state |
| 758 | * enabled by the OS. |
| 759 | */ |
| 760 | xsave_hdr->xstate_bv = XSTATE_FPSSE; |
| 761 | return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct)); |
| 762 | } |
| 763 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 764 | int restore_i387_xstate_ia32(void __user *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | { |
| 766 | int err; |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 767 | struct task_struct *tsk = current; |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 768 | struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 769 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 770 | if (HAVE_HWFP) |
Suresh Siddha | fd3c3ed | 2008-05-07 12:09:52 -0700 | [diff] [blame] | 771 | clear_fpu(tsk); |
| 772 | |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 773 | if (!buf) { |
| 774 | if (used_math()) { |
| 775 | clear_fpu(tsk); |
| 776 | clear_used_math(); |
| 777 | } |
| 778 | |
| 779 | return 0; |
| 780 | } else |
| 781 | if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size)) |
| 782 | return -EACCES; |
| 783 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 784 | if (!used_math()) { |
| 785 | err = init_fpu(tsk); |
| 786 | if (err) |
| 787 | return err; |
| 788 | } |
Suresh Siddha | fd3c3ed | 2008-05-07 12:09:52 -0700 | [diff] [blame] | 789 | |
Suresh Siddha | e8a496a | 2008-05-23 16:26:37 -0700 | [diff] [blame] | 790 | if (HAVE_HWFP) { |
Suresh Siddha | c37b5ef | 2008-07-29 10:29:25 -0700 | [diff] [blame] | 791 | if (cpu_has_xsave) |
| 792 | err = restore_i387_xsave(buf); |
| 793 | else if (cpu_has_fxsr) |
| 794 | err = restore_i387_fxsave(fp, sizeof(struct |
| 795 | i387_fxsave_struct)); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 796 | else |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 797 | err = restore_i387_fsave(fp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 798 | } else { |
Roland McGrath | 4421011 | 2008-01-30 13:31:50 +0100 | [diff] [blame] | 799 | err = fpregs_soft_set(current, NULL, |
| 800 | 0, sizeof(struct user_i387_ia32_struct), |
Suresh Siddha | ab51370 | 2008-07-29 10:29:22 -0700 | [diff] [blame] | 801 | NULL, fp) != 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | } |
| 803 | set_used_math(); |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 804 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | return err; |
| 806 | } |
| 807 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | /* |
| 809 | * FPU state for core dumps. |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 810 | * This is only used for a.out dumps now. |
| 811 | * It is declared generically using elf_fpregset_t (which is |
| 812 | * struct user_i387_struct) but is in fact only used for 32-bit |
| 813 | * 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] | 814 | */ |
Cyrill Gorcunov | 3b095a0 | 2008-01-30 13:31:26 +0100 | [diff] [blame] | 815 | int dump_fpu(struct pt_regs *regs, struct user_i387_struct *fpu) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 816 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 817 | struct task_struct *tsk = current; |
Ingo Molnar | f668964 | 2008-03-05 15:37:32 +0100 | [diff] [blame] | 818 | int fpvalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | |
| 820 | fpvalid = !!used_math(); |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 821 | if (fpvalid) |
| 822 | fpvalid = !fpregs_get(tsk, NULL, |
| 823 | 0, sizeof(struct user_i387_ia32_struct), |
| 824 | fpu, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 825 | |
| 826 | return fpvalid; |
| 827 | } |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 828 | EXPORT_SYMBOL(dump_fpu); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 829 | |
Roland McGrath | 60b3b9a | 2008-01-30 13:31:55 +0100 | [diff] [blame] | 830 | #endif /* CONFIG_X86_32 || CONFIG_IA32_EMULATION */ |