3  * FPU register's regset abstraction, for ptrace, core dumps, etc.
8 #include <asm/fpu/api.h>
9 #include <asm/fpu/signal.h>
10 #include <asm/fpu/regset.h>
39  *     owns the FPU then the memory state has to be synchronized and the
40  *     FPU register state preserved. Otherwise fpstate is already in sync.
45 static void sync_fpstate(struct fpu *fpu)  in sync_fpstate()  argument
47 	if (fpu == &current->thread.fpu)  in sync_fpstate()
48 		fpu_sync_fpstate(fpu);  in sync_fpstate()
52  * Invalidate cached FPU registers before modifying the stopped target
55  * This forces the target task on resume to restore the FPU registers from
57  * with the cached FPU registers which discards the modifications.
59 static void fpu_force_restore(struct fpu *fpu)  in fpu_force_restore()  argument
62 	 * Only stopped child tasks can be used to modify the FPU  in fpu_force_restore()
65 	WARN_ON_FPU(fpu == &current->thread.fpu);  in fpu_force_restore()
67 	__fpu_invalidate_fpregs_state(fpu);  in fpu_force_restore()
73 	struct fpu *fpu = &target->thread.fpu;  in xfpregs_get()  local
78 	sync_fpstate(fpu);  in xfpregs_get()
81 		return membuf_write(&to, &fpu->fpstate->regs.fxsave,  in xfpregs_get()
82 				    sizeof(fpu->fpstate->regs.fxsave));  in xfpregs_get()
93 	struct fpu *fpu = &target->thread.fpu;  in xfpregs_set()  local
112 	fpu_force_restore(fpu);  in xfpregs_set()
115 	memcpy(&fpu->fpstate->regs.fxsave, &newstate, sizeof(newstate));  in xfpregs_set()
118 	BUILD_BUG_ON(sizeof(fpu->__fpstate.regs.fxsave.xmm_space) != 16 * 16);  in xfpregs_set()
120 		memset(&fpu->fpstate->regs.fxsave.xmm_space[8*4], 0, 8 * 16);  in xfpregs_set()
124 		fpu->fpstate->regs.xsave.header.xfeatures |= XFEATURE_MASK_FPSSE;  in xfpregs_set()
135 	sync_fpstate(&target->thread.fpu);  in xstateregs_get()
145 	struct fpu *fpu = &target->thread.fpu;  in xstateregs_set()  local
169 	fpu_force_restore(fpu);  in xstateregs_set()
170 	ret = copy_uabi_from_kernel_to_xstate(fpu->fpstate, kbuf ?: tmpbuf);  in xstateregs_set()
180  * FPU tag word conversions.
265 	 * should be actually ds/cs at fpu exception time, but  in __convert_from_fxsr()
289 	__convert_from_fxsr(env, tsk, &tsk->thread.fpu.fpstate->regs.fxsave);  in convert_from_fxsr()
322 	struct fpu *fpu = &target->thread.fpu;  in fpregs_get()  local
326 	sync_fpstate(fpu);  in fpregs_get()
332 		return membuf_write(&to, &fpu->fpstate->regs.fsave,  in fpregs_get()
343 		fx = &fpu->fpstate->regs.fxsave;  in fpregs_get()
354 	struct fpu *fpu = &target->thread.fpu;  in fpregs_set()  local
369 	fpu_force_restore(fpu);  in fpregs_set()
372 		convert_to_fxsr(&fpu->fpstate->regs.fxsave, &env);  in fpregs_set()
374 		memcpy(&fpu->fpstate->regs.fsave, &env, sizeof(env));  in fpregs_set()
381 		fpu->fpstate->regs.xsave.header.xfeatures |= XFEATURE_MASK_FP;  in fpregs_set()