• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 #ifndef __ASSEMBLY__
27 
28 #include <linux/build_bug.h>
29 #include <linux/cache.h>
30 #include <linux/init.h>
31 #include <linux/stddef.h>
32 #include <linux/string.h>
33 #include <linux/thread_info.h>
34 #include <linux/android_vendor.h>
35 
36 #include <vdso/processor.h>
37 
38 #include <asm/alternative.h>
39 #include <asm/cpufeature.h>
40 #include <asm/hw_breakpoint.h>
41 #include <asm/kasan.h>
42 #include <asm/lse.h>
43 #include <asm/pgtable-hwdef.h>
44 #include <asm/pointer_auth.h>
45 #include <asm/ptrace.h>
46 #include <asm/spectre.h>
47 #include <asm/types.h>
48 
49 /*
50  * TASK_SIZE - the maximum size of a user space task.
51  * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
52  */
53 
54 #define DEFAULT_MAP_WINDOW_64	(UL(1) << VA_BITS_MIN)
55 #define TASK_SIZE_64		(UL(1) << vabits_actual)
56 #define TASK_SIZE_MAX		(UL(1) << VA_BITS)
57 
58 #ifdef CONFIG_COMPAT
59 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS)
60 /*
61  * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
62  * by the compat vectors page.
63  */
64 #define TASK_SIZE_32		UL(0x100000000)
65 #else
66 #define TASK_SIZE_32		(UL(0x100000000) - PAGE_SIZE)
67 #endif /* CONFIG_ARM64_64K_PAGES */
68 #define TASK_SIZE		(test_thread_flag(TIF_32BIT) ? \
69 				TASK_SIZE_32 : TASK_SIZE_64)
70 #define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_32BIT) ? \
71 				TASK_SIZE_32 : TASK_SIZE_64)
72 #define DEFAULT_MAP_WINDOW	(test_thread_flag(TIF_32BIT) ? \
73 				TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64)
74 #else
75 #define TASK_SIZE		TASK_SIZE_64
76 #define DEFAULT_MAP_WINDOW	DEFAULT_MAP_WINDOW_64
77 #endif /* CONFIG_COMPAT */
78 
79 #ifdef CONFIG_ARM64_FORCE_52BIT
80 #define STACK_TOP_MAX		TASK_SIZE_64
81 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(TASK_SIZE / 4))
82 #else
83 #define STACK_TOP_MAX		DEFAULT_MAP_WINDOW_64
84 #define TASK_UNMAPPED_BASE	(PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4))
85 #endif /* CONFIG_ARM64_FORCE_52BIT */
86 
87 #ifdef CONFIG_COMPAT
88 #define AARCH32_VECTORS_BASE	0xffff0000
89 #define STACK_TOP		(test_thread_flag(TIF_32BIT) ? \
90 				AARCH32_VECTORS_BASE : STACK_TOP_MAX)
91 #else
92 #define STACK_TOP		STACK_TOP_MAX
93 #endif /* CONFIG_COMPAT */
94 
95 #ifndef CONFIG_ARM64_FORCE_52BIT
96 #define arch_get_mmap_end(addr, len, flags) \
97 		(((addr) > DEFAULT_MAP_WINDOW) ? TASK_SIZE : DEFAULT_MAP_WINDOW)
98 
99 #define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \
100 					base + TASK_SIZE - DEFAULT_MAP_WINDOW :\
101 					base)
102 #endif /* CONFIG_ARM64_FORCE_52BIT */
103 
104 extern phys_addr_t arm64_dma_phys_limit;
105 #define ARCH_LOW_ADDRESS_LIMIT	(arm64_dma_phys_limit - 1)
106 
107 struct debug_info {
108 #ifdef CONFIG_HAVE_HW_BREAKPOINT
109 	/* Have we suspended stepping by a debugger? */
110 	int			suspended_step;
111 	/* Allow breakpoints and watchpoints to be disabled for this thread. */
112 	int			bps_disabled;
113 	int			wps_disabled;
114 	/* Hardware breakpoints pinned to this task. */
115 	struct perf_event	*hbp_break[ARM_MAX_BRP];
116 	struct perf_event	*hbp_watch[ARM_MAX_WRP];
117 #endif
118 };
119 
120 enum vec_type {
121 	ARM64_VEC_SVE = 0,
122 	ARM64_VEC_SME,
123 	ARM64_VEC_MAX,
124 };
125 
126 enum fp_type {
127 	FP_STATE_CURRENT,	/* Save based on current task state. */
128 	FP_STATE_FPSIMD,
129 	FP_STATE_SVE,
130 };
131 
132 struct cpu_context {
133 	unsigned long x19;
134 	unsigned long x20;
135 	unsigned long x21;
136 	unsigned long x22;
137 	unsigned long x23;
138 	unsigned long x24;
139 	unsigned long x25;
140 	unsigned long x26;
141 	unsigned long x27;
142 	unsigned long x28;
143 	unsigned long fp;
144 	unsigned long sp;
145 	unsigned long pc;
146 };
147 
148 struct thread_struct {
149 	struct cpu_context	cpu_context;	/* cpu context */
150 
151 	/*
152 	 * Whitelisted fields for hardened usercopy:
153 	 * Maintainers must ensure manually that this contains no
154 	 * implicit padding.
155 	 */
156 	struct {
157 		unsigned long	tp_value;	/* TLS register */
158 		unsigned long	tp2_value;
159 		struct user_fpsimd_state fpsimd_state;
160 	} uw;
161 
162 	enum fp_type		fp_type;	/* registers FPSIMD or SVE? */
163 	unsigned int		fpsimd_cpu;
164 	void			*sve_state;	/* SVE registers, if any */
165 	void			*sme_state;	/* ZA and ZT state, if any */
166 	unsigned int		vl[ARM64_VEC_MAX];	/* vector length */
167 	unsigned int		vl_onexec[ARM64_VEC_MAX]; /* vl after next exec */
168 	unsigned long		fault_address;	/* fault info */
169 	unsigned long		fault_code;	/* ESR_EL1 value */
170 	struct debug_info	debug;		/* debugging */
171 #ifdef CONFIG_ARM64_PTR_AUTH
172 	struct ptrauth_keys_user	keys_user;
173 #ifdef CONFIG_ARM64_PTR_AUTH_KERNEL
174 	struct ptrauth_keys_kernel	keys_kernel;
175 #endif
176 #endif
177 #ifdef CONFIG_ARM64_MTE
178 	u64			mte_ctrl;
179 #endif
180 	u64			sctlr_user;
181 	u64			svcr;
182 	u64			tpidr2_el0;
183 	ANDROID_VENDOR_DATA(1);
184 };
185 
thread_get_vl(struct thread_struct * thread,enum vec_type type)186 static inline unsigned int thread_get_vl(struct thread_struct *thread,
187 					 enum vec_type type)
188 {
189 	return thread->vl[type];
190 }
191 
thread_get_sve_vl(struct thread_struct * thread)192 static inline unsigned int thread_get_sve_vl(struct thread_struct *thread)
193 {
194 	return thread_get_vl(thread, ARM64_VEC_SVE);
195 }
196 
thread_get_sme_vl(struct thread_struct * thread)197 static inline unsigned int thread_get_sme_vl(struct thread_struct *thread)
198 {
199 	return thread_get_vl(thread, ARM64_VEC_SME);
200 }
201 
thread_get_cur_vl(struct thread_struct * thread)202 static inline unsigned int thread_get_cur_vl(struct thread_struct *thread)
203 {
204 	if (system_supports_sme() && (thread->svcr & SVCR_SM_MASK))
205 		return thread_get_sme_vl(thread);
206 	else
207 		return thread_get_sve_vl(thread);
208 }
209 
210 unsigned int task_get_vl(const struct task_struct *task, enum vec_type type);
211 void task_set_vl(struct task_struct *task, enum vec_type type,
212 		 unsigned long vl);
213 void task_set_vl_onexec(struct task_struct *task, enum vec_type type,
214 			unsigned long vl);
215 unsigned int task_get_vl_onexec(const struct task_struct *task,
216 				enum vec_type type);
217 
task_get_sve_vl(const struct task_struct * task)218 static inline unsigned int task_get_sve_vl(const struct task_struct *task)
219 {
220 	return task_get_vl(task, ARM64_VEC_SVE);
221 }
222 
task_get_sme_vl(const struct task_struct * task)223 static inline unsigned int task_get_sme_vl(const struct task_struct *task)
224 {
225 	return task_get_vl(task, ARM64_VEC_SME);
226 }
227 
task_set_sve_vl(struct task_struct * task,unsigned long vl)228 static inline void task_set_sve_vl(struct task_struct *task, unsigned long vl)
229 {
230 	task_set_vl(task, ARM64_VEC_SVE, vl);
231 }
232 
task_get_sve_vl_onexec(const struct task_struct * task)233 static inline unsigned int task_get_sve_vl_onexec(const struct task_struct *task)
234 {
235 	return task_get_vl_onexec(task, ARM64_VEC_SVE);
236 }
237 
task_set_sve_vl_onexec(struct task_struct * task,unsigned long vl)238 static inline void task_set_sve_vl_onexec(struct task_struct *task,
239 					  unsigned long vl)
240 {
241 	task_set_vl_onexec(task, ARM64_VEC_SVE, vl);
242 }
243 
244 #define SCTLR_USER_MASK                                                        \
245 	(SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | SCTLR_ELx_ENDA | SCTLR_ELx_ENDB |   \
246 	 SCTLR_EL1_TCF0_MASK)
247 
arch_thread_struct_whitelist(unsigned long * offset,unsigned long * size)248 static inline void arch_thread_struct_whitelist(unsigned long *offset,
249 						unsigned long *size)
250 {
251 	/* Verify that there is no padding among the whitelisted fields: */
252 	BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) !=
253 		     sizeof_field(struct thread_struct, uw.tp_value) +
254 		     sizeof_field(struct thread_struct, uw.tp2_value) +
255 		     sizeof_field(struct thread_struct, uw.fpsimd_state));
256 
257 	*offset = offsetof(struct thread_struct, uw);
258 	*size = sizeof_field(struct thread_struct, uw);
259 }
260 
261 #ifdef CONFIG_COMPAT
262 #define task_user_tls(t)						\
263 ({									\
264 	unsigned long *__tls;						\
265 	if (is_compat_thread(task_thread_info(t)))			\
266 		__tls = &(t)->thread.uw.tp2_value;			\
267 	else								\
268 		__tls = &(t)->thread.uw.tp_value;			\
269 	__tls;								\
270  })
271 #else
272 #define task_user_tls(t)	(&(t)->thread.uw.tp_value)
273 #endif
274 
275 /* Sync TPIDR_EL0 back to thread_struct for current */
276 void tls_preserve_current_state(void);
277 
278 #define INIT_THREAD {				\
279 	.fpsimd_cpu = NR_CPUS,			\
280 }
281 
start_thread_common(struct pt_regs * regs,unsigned long pc)282 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
283 {
284 	s32 previous_syscall = regs->syscallno;
285 	memset(regs, 0, sizeof(*regs));
286 	regs->syscallno = previous_syscall;
287 	regs->pc = pc;
288 
289 	if (system_uses_irq_prio_masking())
290 		regs->pmr_save = GIC_PRIO_IRQON;
291 }
292 
start_thread(struct pt_regs * regs,unsigned long pc,unsigned long sp)293 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
294 				unsigned long sp)
295 {
296 	start_thread_common(regs, pc);
297 	regs->pstate = PSR_MODE_EL0t;
298 	spectre_v4_enable_task_mitigation(current);
299 	regs->sp = sp;
300 }
301 
302 #ifdef CONFIG_COMPAT
compat_start_thread(struct pt_regs * regs,unsigned long pc,unsigned long sp)303 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
304 				       unsigned long sp)
305 {
306 	start_thread_common(regs, pc);
307 	regs->pstate = PSR_AA32_MODE_USR;
308 	if (pc & 1)
309 		regs->pstate |= PSR_AA32_T_BIT;
310 
311 #ifdef __AARCH64EB__
312 	regs->pstate |= PSR_AA32_E_BIT;
313 #endif
314 
315 	spectre_v4_enable_task_mitigation(current);
316 	regs->compat_sp = sp;
317 }
318 #endif
319 
is_ttbr0_addr(unsigned long addr)320 static __always_inline bool is_ttbr0_addr(unsigned long addr)
321 {
322 	/* entry assembly clears tags for TTBR0 addrs */
323 	return addr < TASK_SIZE;
324 }
325 
is_ttbr1_addr(unsigned long addr)326 static __always_inline bool is_ttbr1_addr(unsigned long addr)
327 {
328 	/* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */
329 	return arch_kasan_reset_tag(addr) >= PAGE_OFFSET;
330 }
331 
332 /* Forward declaration, a strange C thing */
333 struct task_struct;
334 
335 unsigned long __get_wchan(struct task_struct *p);
336 
337 void update_sctlr_el1(u64 sctlr);
338 
339 /* Thread switching */
340 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
341 					 struct task_struct *next);
342 
343 #define task_pt_regs(p) \
344 	((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
345 
346 #define KSTK_EIP(tsk)	((unsigned long)task_pt_regs(tsk)->pc)
347 #define KSTK_ESP(tsk)	user_stack_pointer(task_pt_regs(tsk))
348 
349 /*
350  * Prefetching support
351  */
352 #define ARCH_HAS_PREFETCH
prefetch(const void * ptr)353 static inline void prefetch(const void *ptr)
354 {
355 	asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
356 }
357 
358 #define ARCH_HAS_PREFETCHW
prefetchw(const void * ptr)359 static inline void prefetchw(const void *ptr)
360 {
361 	asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
362 }
363 
364 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */
365 extern void __init minsigstksz_setup(void);
366 
367 /*
368  * Not at the top of the file due to a direct #include cycle between
369  * <asm/fpsimd.h> and <asm/processor.h>.  Deferring this #include
370  * ensures that contents of processor.h are visible to fpsimd.h even if
371  * processor.h is included first.
372  *
373  * These prctl helpers are the only things in this file that require
374  * fpsimd.h.  The core code expects them to be in this header.
375  */
376 #include <asm/fpsimd.h>
377 
378 /* Userspace interface for PR_S[MV]E_{SET,GET}_VL prctl()s: */
379 #define SVE_SET_VL(arg)	sve_set_current_vl(arg)
380 #define SVE_GET_VL()	sve_get_current_vl()
381 #define SME_SET_VL(arg)	sme_set_current_vl(arg)
382 #define SME_GET_VL()	sme_get_current_vl()
383 
384 /* PR_PAC_RESET_KEYS prctl */
385 #define PAC_RESET_KEYS(tsk, arg)	ptrauth_prctl_reset_keys(tsk, arg)
386 
387 /* PR_PAC_{SET,GET}_ENABLED_KEYS prctl */
388 #define PAC_SET_ENABLED_KEYS(tsk, keys, enabled)				\
389 	ptrauth_set_enabled_keys(tsk, keys, enabled)
390 #define PAC_GET_ENABLED_KEYS(tsk) ptrauth_get_enabled_keys(tsk)
391 
392 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
393 /* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */
394 long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg);
395 long get_tagged_addr_ctrl(struct task_struct *task);
396 #define SET_TAGGED_ADDR_CTRL(arg)	set_tagged_addr_ctrl(current, arg)
397 #define GET_TAGGED_ADDR_CTRL()		get_tagged_addr_ctrl(current)
398 #endif
399 
400 #endif /* __ASSEMBLY__ */
401 #endif /* __ASM_PROCESSOR_H */
402