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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __X86_KERNEL_FPU_XSTATE_H
3#define __X86_KERNEL_FPU_XSTATE_H
4
5#include <asm/cpufeature.h>
6#include <asm/fpu/xstate.h>
7#include <asm/fpu/xcr.h>
8
9#ifdef CONFIG_X86_64
10DECLARE_PER_CPU(u64, xfd_state);
11#endif
12
13static inline void xstate_init_xcomp_bv(struct xregs_state *xsave, u64 mask)
14{
15 /*
16 * XRSTORS requires these bits set in xcomp_bv, or it will
17 * trigger #GP:
18 */
19 if (cpu_feature_enabled(X86_FEATURE_XCOMPACTED))
20 xsave->header.xcomp_bv = mask | XCOMP_BV_COMPACTED_FORMAT;
21}
22
23static inline u64 xstate_get_group_perm(bool guest)
24{
25 struct fpu *fpu = ¤t->group_leader->thread.fpu;
26 struct fpu_state_perm *perm;
27
28 /* Pairs with WRITE_ONCE() in xstate_request_perm() */
29 perm = guest ? &fpu->guest_perm : &fpu->perm;
30 return READ_ONCE(perm->__state_perm);
31}
32
33static inline u64 xstate_get_host_group_perm(void)
34{
35 return xstate_get_group_perm(false);
36}
37
38enum xstate_copy_mode {
39 XSTATE_COPY_FP,
40 XSTATE_COPY_FX,
41 XSTATE_COPY_XSAVE,
42};
43
44struct membuf;
45extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
46 u32 pkru_val, enum xstate_copy_mode copy_mode);
47extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
48 enum xstate_copy_mode mode);
49extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru);
50extern int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf);
51
52
53extern void fpu__init_cpu_xstate(void);
54extern void fpu__init_system_xstate(unsigned int legacy_size);
55
56extern void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
57
58static inline u64 xfeatures_mask_supervisor(void)
59{
60 return fpu_kernel_cfg.max_features & XFEATURE_MASK_SUPERVISOR_SUPPORTED;
61}
62
63static inline u64 xfeatures_mask_independent(void)
64{
65 if (!cpu_feature_enabled(X86_FEATURE_ARCH_LBR))
66 return XFEATURE_MASK_INDEPENDENT & ~XFEATURE_MASK_LBR;
67
68 return XFEATURE_MASK_INDEPENDENT;
69}
70
71/* XSAVE/XRSTOR wrapper functions */
72
73#ifdef CONFIG_X86_64
74#define REX_PREFIX "0x48, "
75#else
76#define REX_PREFIX
77#endif
78
79/* These macros all use (%edi)/(%rdi) as the single memory argument. */
80#define XSAVE ".byte " REX_PREFIX "0x0f,0xae,0x27"
81#define XSAVEOPT ".byte " REX_PREFIX "0x0f,0xae,0x37"
82#define XSAVEC ".byte " REX_PREFIX "0x0f,0xc7,0x27"
83#define XSAVES ".byte " REX_PREFIX "0x0f,0xc7,0x2f"
84#define XRSTOR ".byte " REX_PREFIX "0x0f,0xae,0x2f"
85#define XRSTORS ".byte " REX_PREFIX "0x0f,0xc7,0x1f"
86
87/*
88 * After this @err contains 0 on success or the trap number when the
89 * operation raises an exception.
90 */
91#define XSTATE_OP(op, st, lmask, hmask, err) \
92 asm volatile("1:" op "\n\t" \
93 "xor %[err], %[err]\n" \
94 "2:\n\t" \
95 _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_MCE_SAFE) \
96 : [err] "=a" (err) \
97 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
98 : "memory")
99
100/*
101 * If XSAVES is enabled, it replaces XSAVEC because it supports supervisor
102 * states in addition to XSAVEC.
103 *
104 * Otherwise if XSAVEC is enabled, it replaces XSAVEOPT because it supports
105 * compacted storage format in addition to XSAVEOPT.
106 *
107 * Otherwise, if XSAVEOPT is enabled, XSAVEOPT replaces XSAVE because XSAVEOPT
108 * supports modified optimization which is not supported by XSAVE.
109 *
110 * We use XSAVE as a fallback.
111 *
112 * The 661 label is defined in the ALTERNATIVE* macros as the address of the
113 * original instruction which gets replaced. We need to use it here as the
114 * address of the instruction where we might get an exception at.
115 */
116#define XSTATE_XSAVE(st, lmask, hmask, err) \
117 asm volatile(ALTERNATIVE_3(XSAVE, \
118 XSAVEOPT, X86_FEATURE_XSAVEOPT, \
119 XSAVEC, X86_FEATURE_XSAVEC, \
120 XSAVES, X86_FEATURE_XSAVES) \
121 "\n" \
122 "xor %[err], %[err]\n" \
123 "3:\n" \
124 _ASM_EXTABLE_TYPE_REG(661b, 3b, EX_TYPE_EFAULT_REG, %[err]) \
125 : [err] "=r" (err) \
126 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
127 : "memory")
128
129/*
130 * Use XRSTORS to restore context if it is enabled. XRSTORS supports compact
131 * XSAVE area format.
132 */
133#define XSTATE_XRESTORE(st, lmask, hmask) \
134 asm volatile(ALTERNATIVE(XRSTOR, \
135 XRSTORS, X86_FEATURE_XSAVES) \
136 "\n" \
137 "3:\n" \
138 _ASM_EXTABLE_TYPE(661b, 3b, EX_TYPE_FPU_RESTORE) \
139 : \
140 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
141 : "memory")
142
143#if defined(CONFIG_X86_64) && defined(CONFIG_X86_DEBUG_FPU)
144extern void xfd_validate_state(struct fpstate *fpstate, u64 mask, bool rstor);
145#else
146static inline void xfd_validate_state(struct fpstate *fpstate, u64 mask, bool rstor) { }
147#endif
148
149#ifdef CONFIG_X86_64
150static inline void xfd_update_state(struct fpstate *fpstate)
151{
152 if (fpu_state_size_dynamic()) {
153 u64 xfd = fpstate->xfd;
154
155 if (__this_cpu_read(xfd_state) != xfd) {
156 wrmsrl(MSR_IA32_XFD, xfd);
157 __this_cpu_write(xfd_state, xfd);
158 }
159 }
160}
161
162extern int __xfd_enable_feature(u64 which, struct fpu_guest *guest_fpu);
163#else
164static inline void xfd_update_state(struct fpstate *fpstate) { }
165
166static inline int __xfd_enable_feature(u64 which, struct fpu_guest *guest_fpu) {
167 return -EPERM;
168}
169#endif
170
171/*
172 * Save processor xstate to xsave area.
173 *
174 * Uses either XSAVE or XSAVEOPT or XSAVES depending on the CPU features
175 * and command line options. The choice is permanent until the next reboot.
176 */
177static inline void os_xsave(struct fpstate *fpstate)
178{
179 u64 mask = fpstate->xfeatures;
180 u32 lmask = mask;
181 u32 hmask = mask >> 32;
182 int err;
183
184 WARN_ON_FPU(!alternatives_patched);
185 xfd_validate_state(fpstate, mask, false);
186
187 XSTATE_XSAVE(&fpstate->regs.xsave, lmask, hmask, err);
188
189 /* We should never fault when copying to a kernel buffer: */
190 WARN_ON_FPU(err);
191}
192
193/*
194 * Restore processor xstate from xsave area.
195 *
196 * Uses XRSTORS when XSAVES is used, XRSTOR otherwise.
197 */
198static inline void os_xrstor(struct fpstate *fpstate, u64 mask)
199{
200 u32 lmask = mask;
201 u32 hmask = mask >> 32;
202
203 xfd_validate_state(fpstate, mask, true);
204 XSTATE_XRESTORE(&fpstate->regs.xsave, lmask, hmask);
205}
206
207/* Restore of supervisor state. Does not require XFD */
208static inline void os_xrstor_supervisor(struct fpstate *fpstate)
209{
210 u64 mask = xfeatures_mask_supervisor();
211 u32 lmask = mask;
212 u32 hmask = mask >> 32;
213
214 XSTATE_XRESTORE(&fpstate->regs.xsave, lmask, hmask);
215}
216
217/*
218 * XSAVE itself always writes all requested xfeatures. Removing features
219 * from the request bitmap reduces the features which are written.
220 * Generate a mask of features which must be written to a sigframe. The
221 * unset features can be optimized away and not written.
222 *
223 * This optimization is user-visible. Only use for states where
224 * uninitialized sigframe contents are tolerable, like dynamic features.
225 *
226 * Users of buffers produced with this optimization must check XSTATE_BV
227 * to determine which features have been optimized out.
228 */
229static inline u64 xfeatures_need_sigframe_write(void)
230{
231 u64 xfeaures_to_write;
232
233 /* In-use features must be written: */
234 xfeaures_to_write = xfeatures_in_use();
235
236 /* Also write all non-optimizable sigframe features: */
237 xfeaures_to_write |= XFEATURE_MASK_USER_SUPPORTED &
238 ~XFEATURE_MASK_SIGFRAME_INITOPT;
239
240 return xfeaures_to_write;
241}
242
243/*
244 * Save xstate to user space xsave area.
245 *
246 * We don't use modified optimization because xrstor/xrstors might track
247 * a different application.
248 *
249 * We don't use compacted format xsave area for backward compatibility for
250 * old applications which don't understand the compacted format of the
251 * xsave area.
252 *
253 * The caller has to zero buf::header before calling this because XSAVE*
254 * does not touch the reserved fields in the header.
255 */
256static inline int xsave_to_user_sigframe(struct xregs_state __user *buf)
257{
258 /*
259 * Include the features which are not xsaved/rstored by the kernel
260 * internally, e.g. PKRU. That's user space ABI and also required
261 * to allow the signal handler to modify PKRU.
262 */
263 struct fpstate *fpstate = current->thread.fpu.fpstate;
264 u64 mask = fpstate->user_xfeatures;
265 u32 lmask;
266 u32 hmask;
267 int err;
268
269 /* Optimize away writing unnecessary xfeatures: */
270 if (fpu_state_size_dynamic())
271 mask &= xfeatures_need_sigframe_write();
272
273 lmask = mask;
274 hmask = mask >> 32;
275 xfd_validate_state(fpstate, mask, false);
276
277 stac();
278 XSTATE_OP(XSAVE, buf, lmask, hmask, err);
279 clac();
280
281 return err;
282}
283
284/*
285 * Restore xstate from user space xsave area.
286 */
287static inline int xrstor_from_user_sigframe(struct xregs_state __user *buf, u64 mask)
288{
289 struct xregs_state *xstate = ((__force struct xregs_state *)buf);
290 u32 lmask = mask;
291 u32 hmask = mask >> 32;
292 int err;
293
294 xfd_validate_state(current->thread.fpu.fpstate, mask, true);
295
296 stac();
297 XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
298 clac();
299
300 return err;
301}
302
303/*
304 * Restore xstate from kernel space xsave area, return an error code instead of
305 * an exception.
306 */
307static inline int os_xrstor_safe(struct fpstate *fpstate, u64 mask)
308{
309 struct xregs_state *xstate = &fpstate->regs.xsave;
310 u32 lmask = mask;
311 u32 hmask = mask >> 32;
312 int err;
313
314 /* Ensure that XFD is up to date */
315 xfd_update_state(fpstate);
316
317 if (cpu_feature_enabled(X86_FEATURE_XSAVES))
318 XSTATE_OP(XRSTORS, xstate, lmask, hmask, err);
319 else
320 XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
321
322 return err;
323}
324
325
326#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __X86_KERNEL_FPU_XSTATE_H
3#define __X86_KERNEL_FPU_XSTATE_H
4
5#include <asm/cpufeature.h>
6#include <asm/fpu/xstate.h>
7#include <asm/fpu/xcr.h>
8
9#ifdef CONFIG_X86_64
10DECLARE_PER_CPU(u64, xfd_state);
11#endif
12
13static inline void xstate_init_xcomp_bv(struct xregs_state *xsave, u64 mask)
14{
15 /*
16 * XRSTORS requires these bits set in xcomp_bv, or it will
17 * trigger #GP:
18 */
19 if (cpu_feature_enabled(X86_FEATURE_XCOMPACTED))
20 xsave->header.xcomp_bv = mask | XCOMP_BV_COMPACTED_FORMAT;
21}
22
23static inline u64 xstate_get_group_perm(bool guest)
24{
25 struct fpu *fpu = ¤t->group_leader->thread.fpu;
26 struct fpu_state_perm *perm;
27
28 /* Pairs with WRITE_ONCE() in xstate_request_perm() */
29 perm = guest ? &fpu->guest_perm : &fpu->perm;
30 return READ_ONCE(perm->__state_perm);
31}
32
33static inline u64 xstate_get_host_group_perm(void)
34{
35 return xstate_get_group_perm(false);
36}
37
38enum xstate_copy_mode {
39 XSTATE_COPY_FP,
40 XSTATE_COPY_FX,
41 XSTATE_COPY_XSAVE,
42};
43
44struct membuf;
45extern void __copy_xstate_to_uabi_buf(struct membuf to, struct fpstate *fpstate,
46 u64 xfeatures, u32 pkru_val,
47 enum xstate_copy_mode copy_mode);
48extern void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk,
49 enum xstate_copy_mode mode);
50extern int copy_uabi_from_kernel_to_xstate(struct fpstate *fpstate, const void *kbuf, u32 *pkru);
51extern int copy_sigframe_from_user_to_xstate(struct task_struct *tsk, const void __user *ubuf);
52
53
54extern void fpu__init_cpu_xstate(void);
55extern void fpu__init_system_xstate(unsigned int legacy_size);
56
57extern void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
58
59static inline u64 xfeatures_mask_supervisor(void)
60{
61 return fpu_kernel_cfg.max_features & XFEATURE_MASK_SUPERVISOR_SUPPORTED;
62}
63
64static inline u64 xfeatures_mask_independent(void)
65{
66 if (!cpu_feature_enabled(X86_FEATURE_ARCH_LBR))
67 return XFEATURE_MASK_INDEPENDENT & ~XFEATURE_MASK_LBR;
68
69 return XFEATURE_MASK_INDEPENDENT;
70}
71
72/* XSAVE/XRSTOR wrapper functions */
73
74#ifdef CONFIG_X86_64
75#define REX_PREFIX "0x48, "
76#else
77#define REX_PREFIX
78#endif
79
80/* These macros all use (%edi)/(%rdi) as the single memory argument. */
81#define XSAVE ".byte " REX_PREFIX "0x0f,0xae,0x27"
82#define XSAVEOPT ".byte " REX_PREFIX "0x0f,0xae,0x37"
83#define XSAVEC ".byte " REX_PREFIX "0x0f,0xc7,0x27"
84#define XSAVES ".byte " REX_PREFIX "0x0f,0xc7,0x2f"
85#define XRSTOR ".byte " REX_PREFIX "0x0f,0xae,0x2f"
86#define XRSTORS ".byte " REX_PREFIX "0x0f,0xc7,0x1f"
87
88/*
89 * After this @err contains 0 on success or the trap number when the
90 * operation raises an exception.
91 */
92#define XSTATE_OP(op, st, lmask, hmask, err) \
93 asm volatile("1:" op "\n\t" \
94 "xor %[err], %[err]\n" \
95 "2:\n\t" \
96 _ASM_EXTABLE_TYPE(1b, 2b, EX_TYPE_FAULT_MCE_SAFE) \
97 : [err] "=a" (err) \
98 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
99 : "memory")
100
101/*
102 * If XSAVES is enabled, it replaces XSAVEC because it supports supervisor
103 * states in addition to XSAVEC.
104 *
105 * Otherwise if XSAVEC is enabled, it replaces XSAVEOPT because it supports
106 * compacted storage format in addition to XSAVEOPT.
107 *
108 * Otherwise, if XSAVEOPT is enabled, XSAVEOPT replaces XSAVE because XSAVEOPT
109 * supports modified optimization which is not supported by XSAVE.
110 *
111 * We use XSAVE as a fallback.
112 *
113 * The 661 label is defined in the ALTERNATIVE* macros as the address of the
114 * original instruction which gets replaced. We need to use it here as the
115 * address of the instruction where we might get an exception at.
116 */
117#define XSTATE_XSAVE(st, lmask, hmask, err) \
118 asm volatile(ALTERNATIVE_3(XSAVE, \
119 XSAVEOPT, X86_FEATURE_XSAVEOPT, \
120 XSAVEC, X86_FEATURE_XSAVEC, \
121 XSAVES, X86_FEATURE_XSAVES) \
122 "\n" \
123 "xor %[err], %[err]\n" \
124 "3:\n" \
125 _ASM_EXTABLE_TYPE_REG(661b, 3b, EX_TYPE_EFAULT_REG, %[err]) \
126 : [err] "=r" (err) \
127 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
128 : "memory")
129
130/*
131 * Use XRSTORS to restore context if it is enabled. XRSTORS supports compact
132 * XSAVE area format.
133 */
134#define XSTATE_XRESTORE(st, lmask, hmask) \
135 asm volatile(ALTERNATIVE(XRSTOR, \
136 XRSTORS, X86_FEATURE_XSAVES) \
137 "\n" \
138 "3:\n" \
139 _ASM_EXTABLE_TYPE(661b, 3b, EX_TYPE_FPU_RESTORE) \
140 : \
141 : "D" (st), "m" (*st), "a" (lmask), "d" (hmask) \
142 : "memory")
143
144#if defined(CONFIG_X86_64) && defined(CONFIG_X86_DEBUG_FPU)
145extern void xfd_validate_state(struct fpstate *fpstate, u64 mask, bool rstor);
146#else
147static inline void xfd_validate_state(struct fpstate *fpstate, u64 mask, bool rstor) { }
148#endif
149
150#ifdef CONFIG_X86_64
151static inline void xfd_set_state(u64 xfd)
152{
153 wrmsrl(MSR_IA32_XFD, xfd);
154 __this_cpu_write(xfd_state, xfd);
155}
156
157static inline void xfd_update_state(struct fpstate *fpstate)
158{
159 if (fpu_state_size_dynamic()) {
160 u64 xfd = fpstate->xfd;
161
162 if (__this_cpu_read(xfd_state) != xfd)
163 xfd_set_state(xfd);
164 }
165}
166
167extern int __xfd_enable_feature(u64 which, struct fpu_guest *guest_fpu);
168#else
169static inline void xfd_set_state(u64 xfd) { }
170
171static inline void xfd_update_state(struct fpstate *fpstate) { }
172
173static inline int __xfd_enable_feature(u64 which, struct fpu_guest *guest_fpu) {
174 return -EPERM;
175}
176#endif
177
178/*
179 * Save processor xstate to xsave area.
180 *
181 * Uses either XSAVE or XSAVEOPT or XSAVES depending on the CPU features
182 * and command line options. The choice is permanent until the next reboot.
183 */
184static inline void os_xsave(struct fpstate *fpstate)
185{
186 u64 mask = fpstate->xfeatures;
187 u32 lmask = mask;
188 u32 hmask = mask >> 32;
189 int err;
190
191 WARN_ON_FPU(!alternatives_patched);
192 xfd_validate_state(fpstate, mask, false);
193
194 XSTATE_XSAVE(&fpstate->regs.xsave, lmask, hmask, err);
195
196 /* We should never fault when copying to a kernel buffer: */
197 WARN_ON_FPU(err);
198}
199
200/*
201 * Restore processor xstate from xsave area.
202 *
203 * Uses XRSTORS when XSAVES is used, XRSTOR otherwise.
204 */
205static inline void os_xrstor(struct fpstate *fpstate, u64 mask)
206{
207 u32 lmask = mask;
208 u32 hmask = mask >> 32;
209
210 xfd_validate_state(fpstate, mask, true);
211 XSTATE_XRESTORE(&fpstate->regs.xsave, lmask, hmask);
212}
213
214/* Restore of supervisor state. Does not require XFD */
215static inline void os_xrstor_supervisor(struct fpstate *fpstate)
216{
217 u64 mask = xfeatures_mask_supervisor();
218 u32 lmask = mask;
219 u32 hmask = mask >> 32;
220
221 XSTATE_XRESTORE(&fpstate->regs.xsave, lmask, hmask);
222}
223
224/*
225 * XSAVE itself always writes all requested xfeatures. Removing features
226 * from the request bitmap reduces the features which are written.
227 * Generate a mask of features which must be written to a sigframe. The
228 * unset features can be optimized away and not written.
229 *
230 * This optimization is user-visible. Only use for states where
231 * uninitialized sigframe contents are tolerable, like dynamic features.
232 *
233 * Users of buffers produced with this optimization must check XSTATE_BV
234 * to determine which features have been optimized out.
235 */
236static inline u64 xfeatures_need_sigframe_write(void)
237{
238 u64 xfeaures_to_write;
239
240 /* In-use features must be written: */
241 xfeaures_to_write = xfeatures_in_use();
242
243 /* Also write all non-optimizable sigframe features: */
244 xfeaures_to_write |= XFEATURE_MASK_USER_SUPPORTED &
245 ~XFEATURE_MASK_SIGFRAME_INITOPT;
246
247 return xfeaures_to_write;
248}
249
250/*
251 * Save xstate to user space xsave area.
252 *
253 * We don't use modified optimization because xrstor/xrstors might track
254 * a different application.
255 *
256 * We don't use compacted format xsave area for backward compatibility for
257 * old applications which don't understand the compacted format of the
258 * xsave area.
259 *
260 * The caller has to zero buf::header before calling this because XSAVE*
261 * does not touch the reserved fields in the header.
262 */
263static inline int xsave_to_user_sigframe(struct xregs_state __user *buf)
264{
265 /*
266 * Include the features which are not xsaved/rstored by the kernel
267 * internally, e.g. PKRU. That's user space ABI and also required
268 * to allow the signal handler to modify PKRU.
269 */
270 struct fpstate *fpstate = current->thread.fpu.fpstate;
271 u64 mask = fpstate->user_xfeatures;
272 u32 lmask;
273 u32 hmask;
274 int err;
275
276 /* Optimize away writing unnecessary xfeatures: */
277 if (fpu_state_size_dynamic())
278 mask &= xfeatures_need_sigframe_write();
279
280 lmask = mask;
281 hmask = mask >> 32;
282 xfd_validate_state(fpstate, mask, false);
283
284 stac();
285 XSTATE_OP(XSAVE, buf, lmask, hmask, err);
286 clac();
287
288 return err;
289}
290
291/*
292 * Restore xstate from user space xsave area.
293 */
294static inline int xrstor_from_user_sigframe(struct xregs_state __user *buf, u64 mask)
295{
296 struct xregs_state *xstate = ((__force struct xregs_state *)buf);
297 u32 lmask = mask;
298 u32 hmask = mask >> 32;
299 int err;
300
301 xfd_validate_state(current->thread.fpu.fpstate, mask, true);
302
303 stac();
304 XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
305 clac();
306
307 return err;
308}
309
310/*
311 * Restore xstate from kernel space xsave area, return an error code instead of
312 * an exception.
313 */
314static inline int os_xrstor_safe(struct fpstate *fpstate, u64 mask)
315{
316 struct xregs_state *xstate = &fpstate->regs.xsave;
317 u32 lmask = mask;
318 u32 hmask = mask >> 32;
319 int err;
320
321 /* Ensure that XFD is up to date */
322 xfd_update_state(fpstate);
323
324 if (cpu_feature_enabled(X86_FEATURE_XSAVES))
325 XSTATE_OP(XRSTORS, xstate, lmask, hmask, err);
326 else
327 XSTATE_OP(XRSTOR, xstate, lmask, hmask, err);
328
329 return err;
330}
331
332
333#endif