1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * Based on arch/arm/include/asm/processor.h
4 *
5 * Copyright (C) 1995-1999 Russell King
6 * Copyright (C) 2012 ARM Ltd.
7 */
8 #ifndef __ASM_PROCESSOR_H
9 #define __ASM_PROCESSOR_H
10
11 /*
12 * On arm64 systems, unaligned accesses by the CPU are cheap, and so there is
13 * no point in shifting all network buffers by 2 bytes just to make some IP
14 * header fields appear aligned in memory, potentially sacrificing some DMA
15 * performance on some platforms.
16 */
17 #define NET_IP_ALIGN 0
18
19 #define MTE_CTRL_GCR_USER_EXCL_SHIFT 0
20 #define MTE_CTRL_GCR_USER_EXCL_MASK 0xffff
21
22 #define MTE_CTRL_TCF_SYNC (1UL << 16)
23 #define MTE_CTRL_TCF_ASYNC (1UL << 17)
24 #define MTE_CTRL_TCF_ASYMM (1UL << 18)
25
26 #define MTE_CTRL_STORE_ONLY (1UL << 19)
27
28 #ifndef __ASSEMBLER__
29
30 #include <linux/build_bug.h>
31 #include <linux/cache.h>
32 #include <linux/init.h>
33 #include <linux/stddef.h>
34 #include <linux/string.h>
35 #include <linux/thread_info.h>
36
37 #include <vdso/processor.h>
38
39 #include <asm/alternative.h>
40 #include <asm/cpufeature.h>
41 #include <asm/hw_breakpoint.h>
42 #include <asm/kasan.h>
43 #include <asm/lse.h>
44 #include <asm/pgtable-hwdef.h>
45 #include <asm/pointer_auth.h>
46 #include <asm/ptrace.h>
47 #include <asm/spectre.h>
48 #include <asm/types.h>
49
50 /*
51 * TASK_SIZE - the maximum size of a user space task.
52 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
53 */
54
55 #define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN)
56 #define TASK_SIZE_64 (UL(1) << vabits_actual)
57 #define TASK_SIZE_MAX (UL(1) << VA_BITS)
58
59 #ifdef CONFIG_COMPAT
60 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS)
61 /*
62 * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
63 * by the compat vectors page.
64 */
65 #define TASK_SIZE_32 UL(0x100000000)
66 #else
67 #define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE)
68 #endif /* CONFIG_ARM64_64K_PAGES */
69 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
70 TASK_SIZE_32 : TASK_SIZE_64)
71 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
72 TASK_SIZE_32 : TASK_SIZE_64)
73 #define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \
74 TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64)
75 #else
76 #define TASK_SIZE TASK_SIZE_64
77 #define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64
78 #endif /* CONFIG_COMPAT */
79
80 #ifdef CONFIG_ARM64_FORCE_52BIT
81 #define STACK_TOP_MAX TASK_SIZE_64
82 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4))
83 #else
84 #define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64
85 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4))
86 #endif /* CONFIG_ARM64_FORCE_52BIT */
87
88 #ifdef CONFIG_COMPAT
89 #define AARCH32_VECTORS_BASE 0xffff0000
90 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \
91 AARCH32_VECTORS_BASE : STACK_TOP_MAX)
92 #else
93 #define STACK_TOP STACK_TOP_MAX
94 #endif /* CONFIG_COMPAT */
95
96 #ifndef CONFIG_ARM64_FORCE_52BIT
97 #define arch_get_mmap_end(addr, len, flags) \
98 (((addr) > DEFAULT_MAP_WINDOW) ? TASK_SIZE : DEFAULT_MAP_WINDOW)
99
100 #define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \
101 base + TASK_SIZE - DEFAULT_MAP_WINDOW :\
102 base)
103 #endif /* CONFIG_ARM64_FORCE_52BIT */
104
105 extern phys_addr_t arm64_dma_phys_limit;
106 #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1)
107
108 struct debug_info {
109 #ifdef CONFIG_HAVE_HW_BREAKPOINT
110 /* Have we suspended stepping by a debugger? */
111 int suspended_step;
112 /* Allow breakpoints and watchpoints to be disabled for this thread. */
113 int bps_disabled;
114 int wps_disabled;
115 /* Hardware breakpoints pinned to this task. */
116 struct perf_event *hbp_break[ARM_MAX_BRP];
117 struct perf_event *hbp_watch[ARM_MAX_WRP];
118 #endif
119 };
120
121 enum vec_type {
122 ARM64_VEC_SVE = 0,
123 ARM64_VEC_SME,
124 ARM64_VEC_MAX,
125 };
126
127 enum fp_type {
128 FP_STATE_CURRENT, /* Save based on current task state. */
129 FP_STATE_FPSIMD,
130 FP_STATE_SVE,
131 };
132
133 struct cpu_context {
134 unsigned long x19;
135 unsigned long x20;
136 unsigned long x21;
137 unsigned long x22;
138 unsigned long x23;
139 unsigned long x24;
140 unsigned long x25;
141 unsigned long x26;
142 unsigned long x27;
143 unsigned long x28;
144 unsigned long fp;
145 unsigned long sp;
146 unsigned long pc;
147 };
148
149 struct thread_struct {
150 struct cpu_context cpu_context; /* cpu context */
151
152 /*
153 * Whitelisted fields for hardened usercopy:
154 * Maintainers must ensure manually that this contains no
155 * implicit padding.
156 */
157 struct {
158 unsigned long tp_value; /* TLS register */
159 unsigned long tp2_value;
160 u64 fpmr;
161 unsigned long pad;
162 struct user_fpsimd_state fpsimd_state;
163 } uw;
164
165 enum fp_type fp_type; /* registers FPSIMD or SVE? */
166 unsigned int fpsimd_cpu;
167 void *sve_state; /* SVE registers, if any */
168 void *sme_state; /* ZA and ZT state, if any */
169 unsigned int vl[ARM64_VEC_MAX]; /* vector length */
170 unsigned int vl_onexec[ARM64_VEC_MAX]; /* vl after next exec */
171 unsigned long fault_address; /* fault info */
172 unsigned long fault_code; /* ESR_EL1 value */
173 struct debug_info debug; /* debugging */
174
175 /*
176 * Set [cleared] by kernel_neon_begin() [kernel_neon_end()] to the
177 * address of a caller provided buffer that will be used to preserve a
178 * task's kernel mode FPSIMD state while it is scheduled out.
179 */
180 struct user_fpsimd_state *kernel_fpsimd_state;
181 unsigned int kernel_fpsimd_cpu;
182 #ifdef CONFIG_ARM64_PTR_AUTH
183 struct ptrauth_keys_user keys_user;
184 #ifdef CONFIG_ARM64_PTR_AUTH_KERNEL
185 struct ptrauth_keys_kernel keys_kernel;
186 #endif
187 #endif
188 #ifdef CONFIG_ARM64_MTE
189 u64 mte_ctrl;
190 #endif
191 u64 sctlr_user;
192 u64 svcr;
193 u64 tpidr2_el0;
194 u64 por_el0;
195 #ifdef CONFIG_ARM64_GCS
196 unsigned int gcs_el0_mode;
197 unsigned int gcs_el0_locked;
198 u64 gcspr_el0;
199 u64 gcs_base;
200 u64 gcs_size;
201 #endif
202 };
203
thread_get_vl(struct thread_struct * thread,enum vec_type type)204 static inline unsigned int thread_get_vl(struct thread_struct *thread,
205 enum vec_type type)
206 {
207 return thread->vl[type];
208 }
209
thread_get_sve_vl(struct thread_struct * thread)210 static inline unsigned int thread_get_sve_vl(struct thread_struct *thread)
211 {
212 return thread_get_vl(thread, ARM64_VEC_SVE);
213 }
214
thread_get_sme_vl(struct thread_struct * thread)215 static inline unsigned int thread_get_sme_vl(struct thread_struct *thread)
216 {
217 return thread_get_vl(thread, ARM64_VEC_SME);
218 }
219
thread_get_cur_vl(struct thread_struct * thread)220 static inline unsigned int thread_get_cur_vl(struct thread_struct *thread)
221 {
222 if (system_supports_sme() && (thread->svcr & SVCR_SM_MASK))
223 return thread_get_sme_vl(thread);
224 else
225 return thread_get_sve_vl(thread);
226 }
227
228 unsigned int task_get_vl(const struct task_struct *task, enum vec_type type);
229 void task_set_vl(struct task_struct *task, enum vec_type type,
230 unsigned long vl);
231 void task_set_vl_onexec(struct task_struct *task, enum vec_type type,
232 unsigned long vl);
233 unsigned int task_get_vl_onexec(const struct task_struct *task,
234 enum vec_type type);
235
task_get_sve_vl(const struct task_struct * task)236 static inline unsigned int task_get_sve_vl(const struct task_struct *task)
237 {
238 return task_get_vl(task, ARM64_VEC_SVE);
239 }
240
task_get_sme_vl(const struct task_struct * task)241 static inline unsigned int task_get_sme_vl(const struct task_struct *task)
242 {
243 return task_get_vl(task, ARM64_VEC_SME);
244 }
245
task_set_sve_vl(struct task_struct * task,unsigned long vl)246 static inline void task_set_sve_vl(struct task_struct *task, unsigned long vl)
247 {
248 task_set_vl(task, ARM64_VEC_SVE, vl);
249 }
250
task_get_sve_vl_onexec(const struct task_struct * task)251 static inline unsigned int task_get_sve_vl_onexec(const struct task_struct *task)
252 {
253 return task_get_vl_onexec(task, ARM64_VEC_SVE);
254 }
255
task_set_sve_vl_onexec(struct task_struct * task,unsigned long vl)256 static inline void task_set_sve_vl_onexec(struct task_struct *task,
257 unsigned long vl)
258 {
259 task_set_vl_onexec(task, ARM64_VEC_SVE, vl);
260 }
261
262 #define SCTLR_USER_MASK \
263 (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | SCTLR_ELx_ENDA | SCTLR_ELx_ENDB | \
264 SCTLR_EL1_TCF0_MASK)
265
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)266 static inline void arch_thread_struct_whitelist(unsigned long *offset,
267 unsigned long *size)
268 {
269 /* Verify that there is no padding among the whitelisted fields: */
270 BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) !=
271 sizeof_field(struct thread_struct, uw.tp_value) +
272 sizeof_field(struct thread_struct, uw.tp2_value) +
273 sizeof_field(struct thread_struct, uw.fpmr) +
274 sizeof_field(struct thread_struct, uw.pad) +
275 sizeof_field(struct thread_struct, uw.fpsimd_state));
276
277 *offset = offsetof(struct thread_struct, uw);
278 *size = sizeof_field(struct thread_struct, uw);
279 }
280
281 #ifdef CONFIG_COMPAT
282 #define task_user_tls(t) \
283 ({ \
284 unsigned long *__tls; \
285 if (is_compat_thread(task_thread_info(t))) \
286 __tls = &(t)->thread.uw.tp2_value; \
287 else \
288 __tls = &(t)->thread.uw.tp_value; \
289 __tls; \
290 })
291 #else
292 #define task_user_tls(t) (&(t)->thread.uw.tp_value)
293 #endif
294
295 /* Sync TPIDR_EL0 back to thread_struct for current */
296 void tls_preserve_current_state(void);
297
298 #define INIT_THREAD { \
299 .fpsimd_cpu = NR_CPUS, \
300 }
301
start_thread_common(struct pt_regs * regs,unsigned long pc,unsigned long pstate)302 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc,
303 unsigned long pstate)
304 {
305 /*
306 * Ensure all GPRs are zeroed, and initialize PC + PSTATE.
307 * The SP (or compat SP) will be initialized later.
308 */
309 regs->user_regs = (struct user_pt_regs) {
310 .pc = pc,
311 .pstate = pstate,
312 };
313
314 /*
315 * To allow the syscalls:sys_exit_execve tracepoint we need to preserve
316 * syscallno, but do not need orig_x0 or the original GPRs.
317 */
318 regs->orig_x0 = 0;
319
320 /*
321 * An exec from a kernel thread won't have an existing PMR value.
322 */
323 if (system_uses_irq_prio_masking())
324 regs->pmr = GIC_PRIO_IRQON;
325
326 /*
327 * The pt_regs::stackframe field must remain valid throughout this
328 * function as a stacktrace can be taken at any time. Any user or
329 * kernel task should have a valid final frame.
330 */
331 WARN_ON_ONCE(regs->stackframe.record.fp != 0);
332 WARN_ON_ONCE(regs->stackframe.record.lr != 0);
333 WARN_ON_ONCE(regs->stackframe.type != FRAME_META_TYPE_FINAL);
334 }
335
start_thread(struct pt_regs * regs,unsigned long pc,unsigned long sp)336 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
337 unsigned long sp)
338 {
339 start_thread_common(regs, pc, PSR_MODE_EL0t);
340 spectre_v4_enable_task_mitigation(current);
341 regs->sp = sp;
342 }
343
344 #ifdef CONFIG_COMPAT
compat_start_thread(struct pt_regs * regs,unsigned long pc,unsigned long sp)345 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
346 unsigned long sp)
347 {
348 unsigned long pstate = PSR_AA32_MODE_USR;
349 if (pc & 1)
350 pstate |= PSR_AA32_T_BIT;
351 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
352 pstate |= PSR_AA32_E_BIT;
353
354 start_thread_common(regs, pc, pstate);
355 spectre_v4_enable_task_mitigation(current);
356 regs->compat_sp = sp;
357 }
358 #endif
359
is_ttbr0_addr(unsigned long addr)360 static __always_inline bool is_ttbr0_addr(unsigned long addr)
361 {
362 /* entry assembly clears tags for TTBR0 addrs */
363 return addr < TASK_SIZE;
364 }
365
is_ttbr1_addr(unsigned long addr)366 static __always_inline bool is_ttbr1_addr(unsigned long addr)
367 {
368 /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */
369 return arch_kasan_reset_tag(addr) >= PAGE_OFFSET;
370 }
371
372 /* Forward declaration, a strange C thing */
373 struct task_struct;
374
375 unsigned long __get_wchan(struct task_struct *p);
376
377 void update_sctlr_el1(u64 sctlr);
378
379 /* Thread switching */
380 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
381 struct task_struct *next);
382
383 #define task_pt_regs(p) \
384 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
385
386 #define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc)
387 #define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk))
388
389 /*
390 * Prefetching support
391 */
392 #define ARCH_HAS_PREFETCH
prefetch(const void * ptr)393 static inline void prefetch(const void *ptr)
394 {
395 asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
396 }
397
398 #define ARCH_HAS_PREFETCHW
prefetchw(const void * ptr)399 static inline void prefetchw(const void *ptr)
400 {
401 asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
402 }
403
404 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */
405 extern void __init minsigstksz_setup(void);
406
407 /*
408 * Not at the top of the file due to a direct #include cycle between
409 * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include
410 * ensures that contents of processor.h are visible to fpsimd.h even if
411 * processor.h is included first.
412 *
413 * These prctl helpers are the only things in this file that require
414 * fpsimd.h. The core code expects them to be in this header.
415 */
416 #include <asm/fpsimd.h>
417
418 /* Userspace interface for PR_S[MV]E_{SET,GET}_VL prctl()s: */
419 #define SVE_SET_VL(arg) sve_set_current_vl(arg)
420 #define SVE_GET_VL() sve_get_current_vl()
421 #define SME_SET_VL(arg) sme_set_current_vl(arg)
422 #define SME_GET_VL() sme_get_current_vl()
423
424 /* PR_PAC_RESET_KEYS prctl */
425 #define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg)
426
427 /* PR_PAC_{SET,GET}_ENABLED_KEYS prctl */
428 #define PAC_SET_ENABLED_KEYS(tsk, keys, enabled) \
429 ptrauth_set_enabled_keys(tsk, keys, enabled)
430 #define PAC_GET_ENABLED_KEYS(tsk) ptrauth_get_enabled_keys(tsk)
431
432 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
433 /* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */
434 long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg);
435 long get_tagged_addr_ctrl(struct task_struct *task);
436 #define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg)
437 #define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current)
438 #endif
439
440 int get_tsc_mode(unsigned long adr);
441 int set_tsc_mode(unsigned int val);
442 #define GET_TSC_CTL(adr) get_tsc_mode((adr))
443 #define SET_TSC_CTL(val) set_tsc_mode((val))
444
445 #endif /* __ASSEMBLER__ */
446 #endif /* __ASM_PROCESSOR_H */
447