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Merge branch 'x86/xsave' into x86/core

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This commit is contained in:
Ingo Molnar 2008-09-05 09:18:39 +02:00
commit accf0fa697
21 changed files with 899 additions and 184 deletions
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51
arch/x86/ia32/ia32_signal.c
View File

@ -179,9 +179,10 @@ struct sigframe
u32 pretcode;
int sig;
struct sigcontext_ia32 sc;
struct _fpstate_ia32 fpstate;
struct _fpstate_ia32 fpstate_unused; /* look at kernel/sigframe.h */
unsigned int extramask[_COMPAT_NSIG_WORDS-1];
char retcode[8];
/* fp state follows here */
};
struct rt_sigframe
@ -192,8 +193,8 @@ struct rt_sigframe
u32 puc;
compat_siginfo_t info;
struct ucontext_ia32 uc;
struct _fpstate_ia32 fpstate;
char retcode[8];
/* fp state follows here */
};
#define COPY(x) { \
@ -215,7 +216,7 @@ static int ia32_restore_sigcontext(struct pt_regs *regs,
unsigned int *peax)
{
unsigned int tmpflags, gs, oldgs, err = 0;
struct _fpstate_ia32 __user *buf;
void __user *buf;
u32 tmp;
/* Always make any pending restarted system calls return -EINTR */
@ -259,26 +260,12 @@ static int ia32_restore_sigcontext(struct pt_regs *regs,
err |= __get_user(tmp, &sc->fpstate);
buf = compat_ptr(tmp);
if (buf) {
if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= restore_i387_ia32(buf);
} else {
struct task_struct *me = current;
if (used_math()) {
clear_fpu(me);
clear_used_math();
}
}
err |= restore_i387_xstate_ia32(buf);
err |= __get_user(tmp, &sc->ax);
*peax = tmp;
return err;
badframe:
return 1;
}
asmlinkage long sys32_sigreturn(struct pt_regs *regs)
@ -350,7 +337,7 @@ badframe:
*/
static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
struct _fpstate_ia32 __user *fpstate,
void __user *fpstate,
struct pt_regs *regs, unsigned int mask)
{
int tmp, err = 0;
@ -381,7 +368,7 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
err |= __put_user((u32)regs->flags, &sc->flags);
err |= __put_user((u32)regs->sp, &sc->sp_at_signal);
tmp = save_i387_ia32(fpstate);
tmp = save_i387_xstate_ia32(fpstate);
if (tmp < 0)
err = -EFAULT;
else {
@ -402,7 +389,8 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
* Determine which stack to use..
*/
static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
size_t frame_size)
size_t frame_size,
void **fpstate)
{
unsigned long sp;
@ -421,6 +409,11 @@ static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
ka->sa.sa_restorer)
sp = (unsigned long) ka->sa.sa_restorer;
if (used_math()) {
sp = sp - sig_xstate_ia32_size;
*fpstate = (struct _fpstate_ia32 *) sp;
}
sp -= frame_size;
/* Align the stack pointer according to the i386 ABI,
* i.e. so that on function entry ((sp + 4) & 15) == 0. */
@ -434,6 +427,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
struct sigframe __user *frame;
void __user *restorer;
int err = 0;
void __user *fpstate = NULL;
/* copy_to_user optimizes that into a single 8 byte store */
static const struct {
@ -448,7 +442,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
0,
};
frame = get_sigframe(ka, regs, sizeof(*frame));
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@ -457,8 +451,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
if (err)
goto give_sigsegv;
err |= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs,
set->sig[0]);
err |= ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@ -522,6 +515,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
struct rt_sigframe __user *frame;
void __user *restorer;
int err = 0;
void __user *fpstate = NULL;
/* __copy_to_user optimizes that into a single 8 byte store */
static const struct {
@ -537,7 +531,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
0,
};
frame = get_sigframe(ka, regs, sizeof(*frame));
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@ -550,13 +544,16 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
goto give_sigsegv;
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
if (cpu_has_xsave)
err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
else
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)

2
arch/x86/kernel/Makefile
View File

@ -38,7 +38,7 @@ obj-y += tsc.o io_delay.o rtc.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-y += process.o
obj-y += i387.o
obj-y += i387.o xsave.o
obj-y += ptrace.o
obj-y += ds.o
obj-$(CONFIG_X86_32) += tls.o

13
arch/x86/kernel/cpu/common.c
View File

@ -739,9 +739,20 @@ void __cpuinit cpu_init(void)
/*
* Force FPU initialization:
*/
current_thread_info()->status = 0;
if (cpu_has_xsave)
current_thread_info()->status = TS_XSAVE;
else
current_thread_info()->status = 0;
clear_used_math();
mxcsr_feature_mask_init();
/*
* Boot processor to setup the FP and extended state context info.
*/
if (!smp_processor_id())
init_thread_xstate();
xsave_init();
}
#ifdef CONFIG_HOTPLUG_CPU

154
arch/x86/kernel/i387.c
View File

@ -21,9 +21,12 @@
# include <asm/sigcontext32.h>
# include <asm/user32.h>
#else
# define save_i387_ia32 save_i387
# define restore_i387_ia32 restore_i387
# define save_i387_xstate_ia32 save_i387_xstate
# define restore_i387_xstate_ia32 restore_i387_xstate
# define _fpstate_ia32 _fpstate
# define _xstate_ia32 _xstate
# define sig_xstate_ia32_size sig_xstate_size
# define fx_sw_reserved_ia32 fx_sw_reserved
# define user_i387_ia32_struct user_i387_struct
# define user32_fxsr_struct user_fxsr_struct
#endif
@ -36,6 +39,7 @@
static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
unsigned int xstate_size;
unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32);
static struct i387_fxsave_struct fx_scratch __cpuinitdata;
void __cpuinit mxcsr_feature_mask_init(void)
@ -61,6 +65,11 @@ void __init init_thread_xstate(void)
return;
}
if (cpu_has_xsave) {
xsave_cntxt_init();
return;
}
if (cpu_has_fxsr)
xstate_size = sizeof(struct i387_fxsave_struct);
#ifdef CONFIG_X86_32
@ -83,9 +92,19 @@ void __cpuinit fpu_init(void)
write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */
/*
* Boot processor to setup the FP and extended state context info.
*/
if (!smp_processor_id())
init_thread_xstate();
xsave_init();
mxcsr_feature_mask_init();
/* clean state in init */
current_thread_info()->status = 0;
if (cpu_has_xsave)
current_thread_info()->status = TS_XSAVE;
else
current_thread_info()->status = 0;
clear_used_math();
}
#endif /* CONFIG_X86_64 */
@ -195,6 +214,13 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset,
*/
target->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask;
/*
* update the header bits in the xsave header, indicating the
* presence of FP and SSE state.
*/
if (cpu_has_xsave)
target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FPSSE;
return ret;
}
@ -395,6 +421,12 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset,
if (!ret)
convert_to_fxsr(target, &env);
/*
* update the header bit in the xsave header, indicating the
* presence of FP.
*/
if (cpu_has_xsave)
target->thread.xstate->xsave.xsave_hdr.xstate_bv |= XSTATE_FP;
return ret;
}
@ -407,7 +439,6 @@ static inline int save_i387_fsave(struct _fpstate_ia32 __user *buf)
struct task_struct *tsk = current;
struct i387_fsave_struct *fp = &tsk->thread.xstate->fsave;
unlazy_fpu(tsk);
fp->status = fp->swd;
if (__copy_to_user(buf, fp, sizeof(struct i387_fsave_struct)))
return -1;
@ -421,8 +452,6 @@ static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
struct user_i387_ia32_struct env;
int err = 0;
unlazy_fpu(tsk);
convert_from_fxsr(&env, tsk);
if (__copy_to_user(buf, &env, sizeof(env)))
return -1;
@ -432,16 +461,40 @@ static int save_i387_fxsave(struct _fpstate_ia32 __user *buf)
if (err)
return -1;
if (__copy_to_user(&buf->_fxsr_env[0], fx,
sizeof(struct i387_fxsave_struct)))
if (__copy_to_user(&buf->_fxsr_env[0], fx, xstate_size))
return -1;
return 1;
}
int save_i387_ia32(struct _fpstate_ia32 __user *buf)
static int save_i387_xsave(void __user *buf)
{
struct _fpstate_ia32 __user *fx = buf;
int err = 0;
if (save_i387_fxsave(fx) < 0)
return -1;
err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved_ia32,
sizeof(struct _fpx_sw_bytes));
err |= __put_user(FP_XSTATE_MAGIC2,
(__u32 __user *) (buf + sig_xstate_ia32_size
- FP_XSTATE_MAGIC2_SIZE));
if (err)
return -1;
return 1;
}
int save_i387_xstate_ia32(void __user *buf)
{
struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
struct task_struct *tsk = current;
if (!used_math())
return 0;
if (!access_ok(VERIFY_WRITE, buf, sig_xstate_ia32_size))
return -EACCES;
/*
* This will cause a "finit" to be triggered by the next
* attempted FPU operation by the 'current' process.
@ -451,13 +504,17 @@ int save_i387_ia32(struct _fpstate_ia32 __user *buf)
if (!HAVE_HWFP) {
return fpregs_soft_get(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
NULL, buf) ? -1 : 1;
NULL, fp) ? -1 : 1;
}
unlazy_fpu(tsk);
if (cpu_has_xsave)
return save_i387_xsave(fp);
if (cpu_has_fxsr)
return save_i387_fxsave(buf);
return save_i387_fxsave(fp);
else
return save_i387_fsave(buf);
return save_i387_fsave(fp);
}
static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf)
@ -468,14 +525,15 @@ static inline int restore_i387_fsave(struct _fpstate_ia32 __user *buf)
sizeof(struct i387_fsave_struct));
}
static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf)
static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf,
unsigned int size)
{
struct task_struct *tsk = current;
struct user_i387_ia32_struct env;
int err;
err = __copy_from_user(&tsk->thread.xstate->fxsave, &buf->_fxsr_env[0],
sizeof(struct i387_fxsave_struct));
size);
/* mxcsr reserved bits must be masked to zero for security reasons */
tsk->thread.xstate->fxsave.mxcsr &= mxcsr_feature_mask;
if (err || __copy_from_user(&env, buf, sizeof(env)))
@ -485,14 +543,69 @@ static int restore_i387_fxsave(struct _fpstate_ia32 __user *buf)
return 0;
}
int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
static int restore_i387_xsave(void __user *buf)
{
struct _fpx_sw_bytes fx_sw_user;
struct _fpstate_ia32 __user *fx_user =
((struct _fpstate_ia32 __user *) buf);
struct i387_fxsave_struct __user *fx =
(struct i387_fxsave_struct __user *) &fx_user->_fxsr_env[0];
struct xsave_hdr_struct *xsave_hdr =
&current->thread.xstate->xsave.xsave_hdr;
u64 mask;
int err;
if (check_for_xstate(fx, buf, &fx_sw_user))
goto fx_only;
mask = fx_sw_user.xstate_bv;
err = restore_i387_fxsave(buf, fx_sw_user.xstate_size);
xsave_hdr->xstate_bv &= pcntxt_mask;
/*
* These bits must be zero.
*/
xsave_hdr->reserved1[0] = xsave_hdr->reserved1[1] = 0;
/*
* Init the state that is not present in the memory layout
* and enabled by the OS.
*/
mask = ~(pcntxt_mask & ~mask);
xsave_hdr->xstate_bv &= mask;
return err;
fx_only:
/*
* Couldn't find the extended state information in the memory
* layout. Restore the FP/SSE and init the other extended state
* enabled by the OS.
*/
xsave_hdr->xstate_bv = XSTATE_FPSSE;
return restore_i387_fxsave(buf, sizeof(struct i387_fxsave_struct));
}
int restore_i387_xstate_ia32(void __user *buf)
{
int err;
struct task_struct *tsk = current;
struct _fpstate_ia32 __user *fp = (struct _fpstate_ia32 __user *) buf;
if (HAVE_HWFP)
clear_fpu(tsk);
if (!buf) {
if (used_math()) {
clear_fpu(tsk);
clear_used_math();
}
return 0;
} else
if (!access_ok(VERIFY_READ, buf, sig_xstate_ia32_size))
return -EACCES;
if (!used_math()) {
err = init_fpu(tsk);
if (err)
@ -500,14 +613,17 @@ int restore_i387_ia32(struct _fpstate_ia32 __user *buf)
}
if (HAVE_HWFP) {
if (cpu_has_fxsr)
err = restore_i387_fxsave(buf);
if (cpu_has_xsave)
err = restore_i387_xsave(buf);
else if (cpu_has_fxsr)
err = restore_i387_fxsave(fp, sizeof(struct
i387_fxsave_struct));
else
err = restore_i387_fsave(buf);
err = restore_i387_fsave(fp);
} else {
err = fpregs_soft_set(current, NULL,
0, sizeof(struct user_i387_ia32_struct),
NULL, buf) != 0;
NULL, fp) != 0;
}
set_used_math();

14
arch/x86/kernel/sigframe.h
View File

@ -3,9 +3,18 @@ struct sigframe {
char __user *pretcode;
int sig;
struct sigcontext sc;
struct _fpstate fpstate;
/*
* fpstate is unused. fpstate is moved/allocated after
* retcode[] below. This movement allows to have the FP state and the
* future state extensions (xsave) stay together.
* And at the same time retaining the unused fpstate, prevents changing
* the offset of extramask[] in the sigframe and thus prevent any
* legacy application accessing/modifying it.
*/
struct _fpstate fpstate_unused;
unsigned long extramask[_NSIG_WORDS-1];
char retcode[8];
/* fp state follows here */
};
struct rt_sigframe {
@ -15,13 +24,14 @@ struct rt_sigframe {
void __user *puc;
struct siginfo info;
struct ucontext uc;
struct _fpstate fpstate;
char retcode[8];
/* fp state follows here */
};
#else
struct rt_sigframe {
char __user *pretcode;
struct ucontext uc;
struct siginfo info;
/* fp state follows here */
};
#endif

45
arch/x86/kernel/signal_32.c
View File

@ -160,28 +160,14 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
}
{
struct _fpstate __user *buf;
void __user *buf;
err |= __get_user(buf, &sc->fpstate);
if (buf) {
if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= restore_i387(buf);
} else {
struct task_struct *me = current;
if (used_math()) {
clear_fpu(me);
clear_used_math();
}
}
err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
return err;
badframe:
return 1;
}
asmlinkage unsigned long sys_sigreturn(unsigned long __unused)
@ -263,7 +249,7 @@ badframe:
* Set up a signal frame.
*/
static int
setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
struct pt_regs *regs, unsigned long mask)
{
int tmp, err = 0;
@ -290,7 +276,7 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
err |= __put_user(regs->sp, &sc->sp_at_signal);
err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss);
tmp = save_i387(fpstate);
tmp = save_i387_xstate(fpstate);
if (tmp < 0)
err = 1;
else
@ -307,7 +293,8 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
* Determine which stack to use..
*/
static inline void __user *
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
void **fpstate)
{
unsigned long sp;
@ -333,6 +320,11 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
sp = (unsigned long) ka->sa.sa_restorer;
}
if (used_math()) {
sp = sp - sig_xstate_size;
*fpstate = (struct _fpstate *) sp;
}
sp -= frame_size;
/*
* Align the stack pointer according to the i386 ABI,
@ -351,8 +343,9 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
void __user *restorer;
int err = 0;
int usig;
void __user *fpstate = NULL;
frame = get_sigframe(ka, regs, sizeof(*frame));
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@ -367,7 +360,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
if (err)
goto give_sigsegv;
err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
err = setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@ -428,8 +421,9 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
void __user *restorer;
int err = 0;
int usig;
void __user *fpstate = NULL;
frame = get_sigframe(ka, regs, sizeof(*frame));
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@ -448,13 +442,16 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
goto give_sigsegv;
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
if (cpu_has_xsave)
err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
else
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)

95
arch/x86/kernel/signal_64.c
View File

@ -54,69 +54,6 @@ sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
return do_sigaltstack(uss, uoss, regs->sp);
}
/*
* Signal frame handlers.
*/
static inline int save_i387(struct _fpstate __user *buf)
{
struct task_struct *tsk = current;
int err = 0;
BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
sizeof(tsk->thread.xstate->fxsave));
if ((unsigned long)buf % 16)
printk("save_i387: bad fpstate %p\n", buf);
if (!used_math())
return 0;
clear_used_math(); /* trigger finit */
if (task_thread_info(tsk)->status & TS_USEDFPU) {
err = save_i387_checking((struct i387_fxsave_struct __user *)
buf);
if (err)
return err;
task_thread_info(tsk)->status &= ~TS_USEDFPU;
stts();
} else {
if (__copy_to_user(buf, &tsk->thread.xstate->fxsave,
sizeof(struct i387_fxsave_struct)))
return -1;
}
return 1;
}
/*
* This restores directly out of user space. Exceptions are handled.
*/
static inline int restore_i387(struct _fpstate __user *buf)
{
struct task_struct *tsk = current;
int err;
if (!used_math()) {
err = init_fpu(tsk);
if (err)
return err;
}
if (!(task_thread_info(current)->status & TS_USEDFPU)) {
clts();
task_thread_info(current)->status |= TS_USEDFPU;
}
err = restore_fpu_checking((__force struct i387_fxsave_struct *)buf);
if (unlikely(err)) {
/*
* Encountered an error while doing the restore from the
* user buffer, clear the fpu state.
*/
clear_fpu(tsk);
clear_used_math();
}
return err;
}
/*
* Do a signal return; undo the signal stack.
*/
@ -161,25 +98,11 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
{
struct _fpstate __user * buf;
err |= __get_user(buf, &sc->fpstate);
if (buf) {
if (!access_ok(VERIFY_READ, buf, sizeof(*buf)))
goto badframe;
err |= restore_i387(buf);
} else {
struct task_struct *me = current;
if (used_math()) {
clear_fpu(me);
clear_used_math();
}
}
err |= restore_i387_xstate(buf);
}
err |= __get_user(*pax, &sc->ax);
return err;
badframe:
return 1;
}
asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
@ -270,26 +193,23 @@ get_stack(struct k_sigaction *ka, struct pt_regs *regs, unsigned long size)
sp = current->sas_ss_sp + current->sas_ss_size;
}
return (void __user *)round_down(sp - size, 16);
return (void __user *)round_down(sp - size, 64);
}
static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs * regs)
{
struct rt_sigframe __user *frame;
struct _fpstate __user *fp = NULL;
void __user *fp = NULL;
int err = 0;
struct task_struct *me = current;
if (used_math()) {
fp = get_stack(ka, regs, sizeof(struct _fpstate));
fp = get_stack(ka, regs, sig_xstate_size);
frame = (void __user *)round_down(
(unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate)))
goto give_sigsegv;
if (save_i387(fp) < 0)
if (save_i387_xstate(fp) < 0)
err |= -1;
} else
frame = get_stack(ka, regs, sizeof(struct rt_sigframe)) - 8;
@ -304,7 +224,10 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
}
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
if (cpu_has_xsave)
err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
else
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user(me->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->sp),

1
arch/x86/kernel/traps_32.c
View File

@ -1228,7 +1228,6 @@ void __init trap_init(void)
set_bit(SYSCALL_VECTOR, used_vectors);
init_thread_xstate();
/*
* Should be a barrier for any external CPU state:
*/

6
arch/x86/kernel/traps_64.c
View File

@ -1134,7 +1134,7 @@ asmlinkage void math_state_restore(void)
/*
* Paranoid restore. send a SIGSEGV if we fail to restore the state.
*/
if (unlikely(restore_fpu_checking(&me->thread.xstate->fxsave))) {
if (unlikely(restore_fpu_checking(me))) {
stts();
force_sig(SIGSEGV, me);
return;
@ -1172,10 +1172,6 @@ void __init trap_init(void)
#ifdef CONFIG_IA32_EMULATION
set_system_gate(IA32_SYSCALL_VECTOR, ia32_syscall);
#endif
/*
* initialize the per thread extended state:
*/
init_thread_xstate();
/*
* Should be a barrier for any external CPU state:
*/

316
arch/x86/kernel/xsave.c Normal file
View File

@ -0,0 +1,316 @@
/*
* xsave/xrstor support.
*
* Author: Suresh Siddha <suresh.b.siddha@intel.com>
*/
#include <linux/bootmem.h>
#include <linux/compat.h>
#include <asm/i387.h>
#ifdef CONFIG_IA32_EMULATION
#include <asm/sigcontext32.h>
#endif
#include <asm/xcr.h>
/*
* Supported feature mask by the CPU and the kernel.
*/
u64 pcntxt_mask;
struct _fpx_sw_bytes fx_sw_reserved;
#ifdef CONFIG_IA32_EMULATION
struct _fpx_sw_bytes fx_sw_reserved_ia32;
#endif
/*
* Check for the presence of extended state information in the
* user fpstate pointer in the sigcontext.
*/
int check_for_xstate(struct i387_fxsave_struct __user *buf,
void __user *fpstate,
struct _fpx_sw_bytes *fx_sw_user)
{
int min_xstate_size = sizeof(struct i387_fxsave_struct) +
sizeof(struct xsave_hdr_struct);
unsigned int magic2;
int err;
err = __copy_from_user(fx_sw_user, &buf->sw_reserved[0],
sizeof(struct _fpx_sw_bytes));
if (err)
return err;
/*
* First Magic check failed.
*/
if (fx_sw_user->magic1 != FP_XSTATE_MAGIC1)
return -1;
/*
* Check for error scenarios.
*/
if (fx_sw_user->xstate_size < min_xstate_size ||
fx_sw_user->xstate_size > xstate_size ||
fx_sw_user->xstate_size > fx_sw_user->extended_size)
return -1;
err = __get_user(magic2, (__u32 *) (((void *)fpstate) +
fx_sw_user->extended_size -
FP_XSTATE_MAGIC2_SIZE));
/*
* Check for the presence of second magic word at the end of memory
* layout. This detects the case where the user just copied the legacy
* fpstate layout with out copying the extended state information
* in the memory layout.
*/
if (err || magic2 != FP_XSTATE_MAGIC2)
return -1;
return 0;
}
#ifdef CONFIG_X86_64
/*
* Signal frame handlers.
*/
int save_i387_xstate(void __user *buf)
{
struct task_struct *tsk = current;
int err = 0;
if (!access_ok(VERIFY_WRITE, buf, sig_xstate_size))
return -EACCES;
BUG_ON(sig_xstate_size < xstate_size);
if ((unsigned long)buf % 64)
printk("save_i387_xstate: bad fpstate %p\n", buf);
if (!used_math())
return 0;
clear_used_math(); /* trigger finit */
if (task_thread_info(tsk)->status & TS_USEDFPU) {
/*
* Start with clearing the user buffer. This will present a
* clean context for the bytes not touched by the fxsave/xsave.
*/
__clear_user(buf, sig_xstate_size);
if (task_thread_info(tsk)->status & TS_XSAVE)
err = xsave_user(buf);
else
err = fxsave_user(buf);
if (err)
return err;
task_thread_info(tsk)->status &= ~TS_USEDFPU;
stts();
} else {
if (__copy_to_user(buf, &tsk->thread.xstate->fxsave,
xstate_size))
return -1;
}
if (task_thread_info(tsk)->status & TS_XSAVE) {
struct _fpstate __user *fx = buf;
err = __copy_to_user(&fx->sw_reserved, &fx_sw_reserved,
sizeof(struct _fpx_sw_bytes));
err |= __put_user(FP_XSTATE_MAGIC2,
(__u32 __user *) (buf + sig_xstate_size
- FP_XSTATE_MAGIC2_SIZE));
}
return 1;
}
/*
* Restore the extended state if present. Otherwise, restore the FP/SSE
* state.
*/
int restore_user_xstate(void __user *buf)
{
struct _fpx_sw_bytes fx_sw_user;
u64 mask;
int err;
if (((unsigned long)buf % 64) ||
check_for_xstate(buf, buf, &fx_sw_user))
goto fx_only;
mask = fx_sw_user.xstate_bv;
/*
* restore the state passed by the user.
*/
err = xrestore_user(buf, mask);
if (err)
return err;
/*
* init the state skipped by the user.
*/
mask = pcntxt_mask & ~mask;
xrstor_state(init_xstate_buf, mask);
return 0;
fx_only:
/*
* couldn't find the extended state information in the
* memory layout. Restore just the FP/SSE and init all
* the other extended state.
*/
xrstor_state(init_xstate_buf, pcntxt_mask & ~XSTATE_FPSSE);
return fxrstor_checking((__force struct i387_fxsave_struct *)buf);
}
/*
* This restores directly out of user space. Exceptions are handled.
*/
int restore_i387_xstate(void __user *buf)
{
struct task_struct *tsk = current;
int err = 0;
if (!buf) {
if (used_math())
goto clear;
return 0;
} else
if (!access_ok(VERIFY_READ, buf, sig_xstate_size))
return -EACCES;
if (!used_math()) {
err = init_fpu(tsk);
if (err)
return err;
}
if (!(task_thread_info(current)->status & TS_USEDFPU)) {
clts();
task_thread_info(current)->status |= TS_USEDFPU;
}
if (task_thread_info(tsk)->status & TS_XSAVE)
err = restore_user_xstate(buf);
else
err = fxrstor_checking((__force struct i387_fxsave_struct *)
buf);
if (unlikely(err)) {
/*
* Encountered an error while doing the restore from the
* user buffer, clear the fpu state.
*/
clear:
clear_fpu(tsk);
clear_used_math();
}
return err;
}
#endif
/*
* Prepare the SW reserved portion of the fxsave memory layout, indicating
* the presence of the extended state information in the memory layout
* pointed by the fpstate pointer in the sigcontext.
* This will be saved when ever the FP and extended state context is
* saved on the user stack during the signal handler delivery to the user.
*/
void prepare_fx_sw_frame(void)
{
int size_extended = (xstate_size - sizeof(struct i387_fxsave_struct)) +
FP_XSTATE_MAGIC2_SIZE;
sig_xstate_size = sizeof(struct _fpstate) + size_extended;
#ifdef CONFIG_IA32_EMULATION
sig_xstate_ia32_size = sizeof(struct _fpstate_ia32) + size_extended;
#endif
memset(&fx_sw_reserved, 0, sizeof(fx_sw_reserved));
fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
fx_sw_reserved.extended_size = sig_xstate_size;
fx_sw_reserved.xstate_bv = pcntxt_mask;
fx_sw_reserved.xstate_size = xstate_size;
#ifdef CONFIG_IA32_EMULATION
memcpy(&fx_sw_reserved_ia32, &fx_sw_reserved,
sizeof(struct _fpx_sw_bytes));
fx_sw_reserved_ia32.extended_size = sig_xstate_ia32_size;
#endif
}
/*
* Represents init state for the supported extended state.
*/
struct xsave_struct *init_xstate_buf;
#ifdef CONFIG_X86_64
unsigned int sig_xstate_size = sizeof(struct _fpstate);
#endif
/*
* Enable the extended processor state save/restore feature
*/
void __cpuinit xsave_init(void)
{
if (!cpu_has_xsave)
return;
set_in_cr4(X86_CR4_OSXSAVE);
/*
* Enable all the features that the HW is capable of
* and the Linux kernel is aware of.
*/
xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
}
/*
* setup the xstate image representing the init state
*/
void setup_xstate_init(void)
{
init_xstate_buf = alloc_bootmem(xstate_size);
init_xstate_buf->i387.mxcsr = MXCSR_DEFAULT;
}
/*
* Enable and initialize the xsave feature.
*/
void __init xsave_cntxt_init(void)
{
unsigned int eax, ebx, ecx, edx;
cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
pcntxt_mask = eax + ((u64)edx << 32);
if ((pcntxt_mask & XSTATE_FPSSE) != XSTATE_FPSSE) {
printk(KERN_ERR "FP/SSE not shown under xsave features 0x%llx\n",
pcntxt_mask);
BUG();
}
/*
* for now OS knows only about FP/SSE
*/
pcntxt_mask = pcntxt_mask & XCNTXT_MASK;
xsave_init();
/*
* Recompute the context size for enabled features
*/
cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
xstate_size = ebx;
prepare_fx_sw_frame();
setup_xstate_init();
printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%llx, "
"cntxt size 0x%x\n",
pcntxt_mask, xstate_size);
}

7
arch/x86/power/cpu_32.c
View File

@ -11,6 +11,7 @@
#include <linux/suspend.h>
#include <asm/mtrr.h>
#include <asm/mce.h>
#include <asm/xcr.h>
static struct saved_context saved_context;
@ -126,6 +127,12 @@ static void __restore_processor_state(struct saved_context *ctxt)
if (boot_cpu_has(X86_FEATURE_SEP))
enable_sep_cpu();
/*
* restore XCR0 for xsave capable cpu's.
*/
if (cpu_has_xsave)
xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
fix_processor_context();
do_fpu_end();
mtrr_ap_init();

7
arch/x86/power/cpu_64.c
View File

@ -14,6 +14,7 @@
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/mtrr.h>
#include <asm/xcr.h>
static void fix_processor_context(void);
@ -122,6 +123,12 @@ static void __restore_processor_state(struct saved_context *ctxt)
wrmsrl(MSR_GS_BASE, ctxt->gs_base);
wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
/*
* restore XCR0 for xsave capable cpu's.
*/
if (cpu_has_xsave)
xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
fix_processor_context();
do_fpu_end();

84
include/asm-x86/i387.h
View File

@ -19,7 +19,9 @@
#include <asm/sigcontext.h>
#include <asm/user.h>
#include <asm/uaccess.h>
#include <asm/xsave.h>
extern unsigned int sig_xstate_size;
extern void fpu_init(void);
extern void mxcsr_feature_mask_init(void);
extern int init_fpu(struct task_struct *child);
@ -31,12 +33,18 @@ extern user_regset_active_fn fpregs_active, xfpregs_active;
extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get;
extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set;
extern struct _fpx_sw_bytes fx_sw_reserved;
#ifdef CONFIG_IA32_EMULATION
extern unsigned int sig_xstate_ia32_size;
extern struct _fpx_sw_bytes fx_sw_reserved_ia32;
struct _fpstate_ia32;
extern int save_i387_ia32(struct _fpstate_ia32 __user *buf);
extern int restore_i387_ia32(struct _fpstate_ia32 __user *buf);
struct _xstate_ia32;
extern int save_i387_xstate_ia32(void __user *buf);
extern int restore_i387_xstate_ia32(void __user *buf);
#endif
#define X87_FSW_ES (1 << 7) /* Exception Summary */
#ifdef CONFIG_X86_64
/* Ignore delayed exceptions from user space */
@ -47,7 +55,7 @@ static inline void tolerant_fwait(void)
_ASM_EXTABLE(1b, 2b));
}
static inline int restore_fpu_checking(struct i387_fxsave_struct *fx)
static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
{
int err;
@ -67,15 +75,31 @@ static inline int restore_fpu_checking(struct i387_fxsave_struct *fx)
return err;
}
#define X87_FSW_ES (1 << 7) /* Exception Summary */
static inline int restore_fpu_checking(struct task_struct *tsk)
{
if (task_thread_info(tsk)->status & TS_XSAVE)
return xrstor_checking(&tsk->thread.xstate->xsave);
else
return fxrstor_checking(&tsk->thread.xstate->fxsave);
}
/* AMD CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. The kernel data segment can be sometimes 0 and sometimes
new user value. Both should be ok.
Use the PDA as safe address because it should be already in L1. */
static inline void clear_fpu_state(struct i387_fxsave_struct *fx)
static inline void clear_fpu_state(struct task_struct *tsk)
{
struct xsave_struct *xstate = &tsk->thread.xstate->xsave;
struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave;
/*
* xsave header may indicate the init state of the FP.
*/
if ((task_thread_info(tsk)->status & TS_XSAVE) &&
!(xstate->xsave_hdr.xstate_bv & XSTATE_FP))
return;
if (unlikely(fx->swd & X87_FSW_ES))
asm volatile("fnclex");
alternative_input(ASM_NOP8 ASM_NOP2,
@ -84,7 +108,7 @@ static inline void clear_fpu_state(struct i387_fxsave_struct *fx)
X86_FEATURE_FXSAVE_LEAK);
}
static inline int save_i387_checking(struct i387_fxsave_struct __user *fx)
static inline int fxsave_user(struct i387_fxsave_struct __user *fx)
{
int err;
@ -108,7 +132,7 @@ static inline int save_i387_checking(struct i387_fxsave_struct __user *fx)
return err;
}
static inline void __save_init_fpu(struct task_struct *tsk)
static inline void fxsave(struct task_struct *tsk)
{
/* Using "rex64; fxsave %0" is broken because, if the memory operand
uses any extended registers for addressing, a second REX prefix
@ -133,7 +157,16 @@ static inline void __save_init_fpu(struct task_struct *tsk)
: "=m" (tsk->thread.xstate->fxsave)
: "cdaSDb" (&tsk->thread.xstate->fxsave));
#endif
clear_fpu_state(&tsk->thread.xstate->fxsave);
}
static inline void __save_init_fpu(struct task_struct *tsk)
{
if (task_thread_info(tsk)->status & TS_XSAVE)
xsave(tsk);
else
fxsave(tsk);
clear_fpu_state(tsk);
task_thread_info(tsk)->status &= ~TS_USEDFPU;
}
@ -148,6 +181,10 @@ static inline void tolerant_fwait(void)
static inline void restore_fpu(struct task_struct *tsk)
{
if (task_thread_info(tsk)->status & TS_XSAVE) {
xrstor_checking(&tsk->thread.xstate->xsave);
return;
}
/*
* The "nop" is needed to make the instructions the same
* length.
@ -173,6 +210,27 @@ static inline void restore_fpu(struct task_struct *tsk)
*/
static inline void __save_init_fpu(struct task_struct *tsk)
{
if (task_thread_info(tsk)->status & TS_XSAVE) {
struct xsave_struct *xstate = &tsk->thread.xstate->xsave;
struct i387_fxsave_struct *fx = &tsk->thread.xstate->fxsave;
xsave(tsk);
/*
* xsave header may indicate the init state of the FP.
*/
if (!(xstate->xsave_hdr.xstate_bv & XSTATE_FP))
goto end;
if (unlikely(fx->swd & X87_FSW_ES))
asm volatile("fnclex");
/*
* we can do a simple return here or be paranoid :)
*/
goto clear_state;
}
/* Use more nops than strictly needed in case the compiler
varies code */
alternative_input(
@ -182,6 +240,7 @@ static inline void __save_init_fpu(struct task_struct *tsk)
X86_FEATURE_FXSR,
[fx] "m" (tsk->thread.xstate->fxsave),
[fsw] "m" (tsk->thread.xstate->fxsave.swd) : "memory");
clear_state:
/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
is pending. Clear the x87 state here by setting it to fixed
values. safe_address is a random variable that should be in L1 */
@ -191,16 +250,17 @@ static inline void __save_init_fpu(struct task_struct *tsk)
"fildl %[addr]", /* set F?P to defined value */
X86_FEATURE_FXSAVE_LEAK,
[addr] "m" (safe_address));
end:
task_thread_info(tsk)->status &= ~TS_USEDFPU;
}
#endif /* CONFIG_X86_64 */
/*
* Signal frame handlers...
*/
extern int save_i387(struct _fpstate __user *buf);
extern int restore_i387(struct _fpstate __user *buf);
#endif /* CONFIG_X86_64 */
extern int save_i387_xstate(void __user *buf);
extern int restore_i387_xstate(void __user *buf);
static inline void __unlazy_fpu(struct task_struct *tsk)
{

1
include/asm-x86/processor-flags.h
View File

@ -59,6 +59,7 @@
#define X86_CR4_OSFXSR 0x00000200 /* enable fast FPU save and restore */
#define X86_CR4_OSXMMEXCPT 0x00000400 /* enable unmasked SSE exceptions */
#define X86_CR4_VMXE 0x00002000 /* enable VMX virtualization */
#define X86_CR4_OSXSAVE 0x00040000 /* enable xsave and xrestore */
/*
* x86-64 Task Priority Register, CR8

20
include/asm-x86/processor.h
View File

@ -326,7 +326,12 @@ struct i387_fxsave_struct {
/* 16*16 bytes for each XMM-reg = 256 bytes: */
u32 xmm_space[64];
u32 padding[24];
u32 padding[12];
union {
u32 padding1[12];
u32 sw_reserved[12];
};
} __attribute__((aligned(16)));
@ -350,10 +355,23 @@ struct i387_soft_struct {
u32 entry_eip;
};
struct xsave_hdr_struct {
u64 xstate_bv;
u64 reserved1[2];
u64 reserved2[5];
} __attribute__((packed));
struct xsave_struct {
struct i387_fxsave_struct i387;
struct xsave_hdr_struct xsave_hdr;
/* new processor state extensions will go here */
} __attribute__ ((packed, aligned (64)));
union thread_xstate {
struct i387_fsave_struct fsave;
struct i387_fxsave_struct fxsave;
struct i387_soft_struct soft;
struct xsave_struct xsave;
};
#ifdef CONFIG_X86_64

87
include/asm-x86/sigcontext.h
View File

@ -4,6 +4,40 @@
#include <linux/compiler.h>
#include <asm/types.h>
#define FP_XSTATE_MAGIC1 0x46505853U
#define FP_XSTATE_MAGIC2 0x46505845U
#define FP_XSTATE_MAGIC2_SIZE sizeof(FP_XSTATE_MAGIC2)
/*
* bytes 464..511 in the current 512byte layout of fxsave/fxrstor frame
* are reserved for SW usage. On cpu's supporting xsave/xrstor, these bytes
* are used to extended the fpstate pointer in the sigcontext, which now
* includes the extended state information along with fpstate information.
*
* Presence of FP_XSTATE_MAGIC1 at the beginning of this SW reserved
* area and FP_XSTATE_MAGIC2 at the end of memory layout
* (extended_size - FP_XSTATE_MAGIC2_SIZE) indicates the presence of the
* extended state information in the memory layout pointed by the fpstate
* pointer in sigcontext.
*/
struct _fpx_sw_bytes {
__u32 magic1; /* FP_XSTATE_MAGIC1 */
__u32 extended_size; /* total size of the layout referred by
* fpstate pointer in the sigcontext.
*/
__u64 xstate_bv;
/* feature bit mask (including fp/sse/extended
* state) that is present in the memory
* layout.
*/
__u32 xstate_size; /* actual xsave state size, based on the
* features saved in the layout.
* 'extended_size' will be greater than
* 'xstate_size'.
*/
__u32 padding[7]; /* for future use. */
};
#ifdef __i386__
/*
* As documented in the iBCS2 standard..
@ -53,7 +87,13 @@ struct _fpstate {
unsigned long reserved;
struct _fpxreg _fxsr_st[8]; /* FXSR FPU reg data is ignored */
struct _xmmreg _xmm[8];
unsigned long padding[56];
unsigned long padding1[44];
union {
unsigned long padding2[12];
struct _fpx_sw_bytes sw_reserved; /* represents the extended
* state info */
};
};
#define X86_FXSR_MAGIC 0x0000
@ -79,7 +119,15 @@ struct sigcontext {
unsigned long flags;
unsigned long sp_at_signal;
unsigned short ss, __ssh;
struct _fpstate __user *fpstate;
/*
* fpstate is really (struct _fpstate *) or (struct _xstate *)
* depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
* bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
* of extended memory layout. See comments at the defintion of
* (struct _fpx_sw_bytes)
*/
void __user *fpstate; /* zero when no FPU/extended context */
unsigned long oldmask;
unsigned long cr2;
};
@ -130,7 +178,12 @@ struct _fpstate {
__u32 mxcsr_mask;
__u32 st_space[32]; /* 8*16 bytes for each FP-reg */
__u32 xmm_space[64]; /* 16*16 bytes for each XMM-reg */
__u32 reserved2[24];
__u32 reserved2[12];
union {
__u32 reserved3[12];
struct _fpx_sw_bytes sw_reserved; /* represents the extended
* state information */
};
};
#ifdef __KERNEL__
@ -161,7 +214,15 @@ struct sigcontext {
unsigned long trapno;
unsigned long oldmask;
unsigned long cr2;
struct _fpstate __user *fpstate; /* zero when no FPU context */
/*
* fpstate is really (struct _fpstate *) or (struct _xstate *)
* depending on the FP_XSTATE_MAGIC1 encoded in the SW reserved
* bytes of (struct _fpstate) and FP_XSTATE_MAGIC2 present at the end
* of extended memory layout. See comments at the defintion of
* (struct _fpx_sw_bytes)
*/
void __user *fpstate; /* zero when no FPU/extended context */
unsigned long reserved1[8];
};
#else /* __KERNEL__ */
@ -202,4 +263,22 @@ struct sigcontext {
#endif /* !__i386__ */
struct _xsave_hdr {
__u64 xstate_bv;
__u64 reserved1[2];
__u64 reserved2[5];
};
/*
* Extended state pointed by the fpstate pointer in the sigcontext.
* In addition to the fpstate, information encoded in the xstate_hdr
* indicates the presence of other extended state information
* supported by the processor and OS.
*/
struct _xstate {
struct _fpstate fpstate;
struct _xsave_hdr xstate_hdr;
/* new processor state extensions go here */
};
#endif /* ASM_X86__SIGCONTEXT_H */

6
include/asm-x86/sigcontext32.h
View File

@ -40,7 +40,11 @@ struct _fpstate_ia32 {
__u32 reserved;
struct _fpxreg _fxsr_st[8];
struct _xmmreg _xmm[8]; /* It's actually 16 */
__u32 padding[56];
__u32 padding[44];
union {
__u32 padding2[12];
struct _fpx_sw_bytes sw_reserved;
};
};
struct sigcontext_ia32 {

1
include/asm-x86/thread_info.h
View File

@ -239,6 +239,7 @@ static inline struct thread_info *stack_thread_info(void)
#define TS_POLLING 0x0004 /* true if in idle loop
and not sleeping */
#define TS_RESTORE_SIGMASK 0x0008 /* restore signal mask in do_signal() */
#define TS_XSAVE 0x0010 /* Use xsave/xrstor */
#define tsk_is_polling(t) (task_thread_info(t)->status & TS_POLLING)

6
include/asm-x86/ucontext.h
View File

@ -1,6 +1,12 @@
#ifndef ASM_X86__UCONTEXT_H
#define ASM_X86__UCONTEXT_H
#define UC_FP_XSTATE 0x1 /* indicates the presence of extended state
* information in the memory layout pointed
* by the fpstate pointer in the ucontext's
* sigcontext struct (uc_mcontext).
*/
struct ucontext {
unsigned long uc_flags;
struct ucontext *uc_link;

49
include/asm-x86/xcr.h Normal file
View File

@ -0,0 +1,49 @@
/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright 2008 rPath, Inc. - All Rights Reserved
*
* This file is part of the Linux kernel, and is made available under
* the terms of the GNU General Public License version 2 or (at your
* option) any later version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
/*
* asm-x86/xcr.h
*
* Definitions for the eXtended Control Register instructions
*/
#ifndef _ASM_X86_XCR_H
#define _ASM_X86_XCR_H
#define XCR_XFEATURE_ENABLED_MASK 0x00000000
#ifdef __KERNEL__
# ifndef __ASSEMBLY__
#include <linux/types.h>
static inline u64 xgetbv(u32 index)
{
u32 eax, edx;
asm volatile(".byte 0x0f,0x01,0xd0" /* xgetbv */
: "=a" (eax), "=d" (edx)
: "c" (index));
return eax + ((u64)edx << 32);
}
static inline void xsetbv(u32 index, u64 value)
{
u32 eax = value;
u32 edx = value >> 32;
asm volatile(".byte 0x0f,0x01,0xd1" /* xsetbv */
: : "a" (eax), "d" (edx), "c" (index));
}
# endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_X86_XCR_H */

118
include/asm-x86/xsave.h Normal file
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@ -0,0 +1,118 @@
#ifndef __ASM_X86_XSAVE_H
#define __ASM_X86_XSAVE_H
#include <linux/types.h>
#include <asm/processor.h>
#include <asm/i387.h>
#define XSTATE_FP 0x1
#define XSTATE_SSE 0x2
#define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE)
#define FXSAVE_SIZE 512
/*
* These are the features that the OS can handle currently.
*/
#define XCNTXT_MASK (XSTATE_FP | XSTATE_SSE)
#ifdef CONFIG_X86_64
#define REX_PREFIX "0x48, "
#else
#define REX_PREFIX
#endif
extern unsigned int xstate_size;
extern u64 pcntxt_mask;
extern struct xsave_struct *init_xstate_buf;
extern void xsave_cntxt_init(void);
extern void xsave_init(void);
extern int init_fpu(struct task_struct *child);
extern int check_for_xstate(struct i387_fxsave_struct __user *buf,
void __user *fpstate,
struct _fpx_sw_bytes *sw);
static inline int xrstor_checking(struct xsave_struct *fx)
{
int err;
asm volatile("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movl $-1,%[err]\n"
" jmp 2b\n"
".previous\n"
_ASM_EXTABLE(1b, 3b)
: [err] "=r" (err)
: "D" (fx), "m" (*fx), "a" (-1), "d" (-1), "0" (0)
: "memory");
return err;
}
static inline int xsave_user(struct xsave_struct __user *buf)
{
int err;
__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x27\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movl $-1,%[err]\n"
" jmp 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
_ASM_ALIGN "\n"
_ASM_PTR "1b,3b\n"
".previous"
: [err] "=r" (err)
: "D" (buf), "a" (-1), "d" (-1), "0" (0)
: "memory");
if (unlikely(err) && __clear_user(buf, xstate_size))
err = -EFAULT;
/* No need to clear here because the caller clears USED_MATH */
return err;
}
static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask)
{
int err;
struct xsave_struct *xstate = ((__force struct xsave_struct *)buf);
u32 lmask = mask;
u32 hmask = mask >> 32;
__asm__ __volatile__("1: .byte " REX_PREFIX "0x0f,0xae,0x2f\n"
"2:\n"
".section .fixup,\"ax\"\n"
"3: movl $-1,%[err]\n"
" jmp 2b\n"
".previous\n"
".section __ex_table,\"a\"\n"
_ASM_ALIGN "\n"
_ASM_PTR "1b,3b\n"
".previous"
: [err] "=r" (err)
: "D" (xstate), "a" (lmask), "d" (hmask), "0" (0)
: "memory"); /* memory required? */
return err;
}
static inline void xrstor_state(struct xsave_struct *fx, u64 mask)
{
u32 lmask = mask;
u32 hmask = mask >> 32;
asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t"
: : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask)
: "memory");
}
static inline void xsave(struct task_struct *tsk)
{
/* This, however, we can work around by forcing the compiler to select
an addressing mode that doesn't require extended registers. */
__asm__ __volatile__(".byte " REX_PREFIX "0x0f,0xae,0x27"
: : "D" (&(tsk->thread.xstate->xsave)),
"a" (-1), "d"(-1) : "memory");
}
#endif