#ifdef CONFIG_IA32_EMULATION
#include <asm/sigcontext32.h>
#endif
+#include <asm/xcr.h>
/*
* Supported feature mask by the CPU and the kernel.
*/
-unsigned int pcntxt_hmask, pcntxt_lmask;
+u64 pcntxt_mask;
struct _fpx_sw_bytes fx_sw_reserved;
#ifdef CONFIG_IA32_EMULATION
if (!access_ok(VERIFY_WRITE, buf, sig_xstate_size))
return -EACCES;
- BUILD_BUG_ON(sizeof(struct user_i387_struct) !=
- sizeof(tsk->thread.xstate->fxsave));
+ BUG_ON(sig_xstate_size < xstate_size);
if ((unsigned long)buf % 64)
printk("save_i387_xstate: bad fpstate %p\n", buf);
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.
+ */
+ err = __clear_user(buf, sig_xstate_size);
+ if (err)
+ return err;
+
if (task_thread_info(tsk)->status & TS_XSAVE)
err = xsave_user(buf);
else
if (task_thread_info(tsk)->status & TS_XSAVE) {
struct _fpstate __user *fx = buf;
+ struct _xstate __user *x = buf;
+ u64 xstate_bv;
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));
+
+ /*
+ * Read the xstate_bv which we copied (directly from the cpu or
+ * from the state in task struct) to the user buffers and
+ * set the FP/SSE bits.
+ */
+ err |= __get_user(xstate_bv, &x->xstate_hdr.xstate_bv);
+
+ /*
+ * For legacy compatible, we always set FP/SSE bits in the bit
+ * vector while saving the state to the user context. This will
+ * enable us capturing any changes(during sigreturn) to
+ * the FP/SSE bits by the legacy applications which don't touch
+ * xstate_bv in the xsave header.
+ *
+ * xsave aware apps can change the xstate_bv in the xsave
+ * header as well as change any contents in the memory layout.
+ * xrestore as part of sigreturn will capture all the changes.
+ */
+ xstate_bv |= XSTATE_FPSSE;
+
+ err |= __put_user(xstate_bv, &x->xstate_hdr.xstate_bv);
+
+ if (err)
+ return err;
}
return 1;
int restore_user_xstate(void __user *buf)
{
struct _fpx_sw_bytes fx_sw_user;
- unsigned int lmask, hmask;
+ u64 mask;
int err;
if (((unsigned long)buf % 64) ||
check_for_xstate(buf, buf, &fx_sw_user))
goto fx_only;
- lmask = fx_sw_user.xstate_bv;
- hmask = fx_sw_user.xstate_bv >> 32;
+ mask = fx_sw_user.xstate_bv;
/*
* restore the state passed by the user.
*/
- err = xrestore_user(buf, lmask, hmask);
+ err = xrestore_user(buf, mask);
if (err)
return err;
/*
* init the state skipped by the user.
*/
- lmask = pcntxt_lmask & ~lmask;
- hmask = pcntxt_hmask & ~hmask;
+ mask = pcntxt_mask & ~mask;
- xrstor_state(init_xstate_buf, lmask, hmask);
+ xrstor_state(init_xstate_buf, mask);
return 0;
* memory layout. Restore just the FP/SSE and init all
* the other extended state.
*/
- xrstor_state(init_xstate_buf, pcntxt_lmask & ~XSTATE_FPSSE,
- pcntxt_hmask);
+ xrstor_state(init_xstate_buf, pcntxt_mask & ~XSTATE_FPSSE);
return fxrstor_checking((__force struct i387_fxsave_struct *)buf);
}
* 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)
+static void prepare_fx_sw_frame(void)
{
int size_extended = (xstate_size - sizeof(struct i387_fxsave_struct)) +
FP_XSTATE_MAGIC2_SIZE;
fx_sw_reserved.magic1 = FP_XSTATE_MAGIC1;
fx_sw_reserved.extended_size = sig_xstate_size;
- fx_sw_reserved.xstate_bv = pcntxt_lmask |
- (((u64) (pcntxt_hmask)) << 32);
+ 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,
/*
* Enable all the features that the HW is capable of
* and the Linux kernel is aware of.
- *
- * xsetbv();
*/
- asm volatile(".byte 0x0f,0x01,0xd1" : : "c" (0),
- "a" (pcntxt_lmask), "d" (pcntxt_hmask));
+ xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask);
}
/*
* setup the xstate image representing the init state
*/
-void setup_xstate_init(void)
+static void __init setup_xstate_init(void)
{
init_xstate_buf = alloc_bootmem(xstate_size);
init_xstate_buf->i387.mxcsr = MXCSR_DEFAULT;
unsigned int eax, ebx, ecx, edx;
cpuid_count(0xd, 0, &eax, &ebx, &ecx, &edx);
+ pcntxt_mask = eax + ((u64)edx << 32);
- pcntxt_lmask = eax;
- pcntxt_hmask = edx;
-
- if ((pcntxt_lmask & XSTATE_FPSSE) != XSTATE_FPSSE) {
- printk(KERN_ERR "FP/SSE not shown under xsave features %x\n",
- pcntxt_lmask);
+ 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_lmask = pcntxt_lmask & XCNTXT_LMASK;
- pcntxt_hmask = pcntxt_hmask & XCNTXT_HMASK;
-
+ 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%Lx, "
+ printk(KERN_INFO "xsave/xrstor: enabled xstate_bv 0x%llx, "
"cntxt size 0x%x\n",
- (pcntxt_lmask | ((u64) pcntxt_hmask << 32)), xstate_size);
+ pcntxt_mask, xstate_size);
}
projects / linux-2.6-omap-h63xx.git / blobdiff