1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Based on arch/arm/include/asm/processor.h
5 * Copyright (C) 1995-1999 Russell King
6 * Copyright (C) 2012 ARM Ltd.
8 #ifndef __ASM_PROCESSOR_H
9 #define __ASM_PROCESSOR_H
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.
17 #define NET_IP_ALIGN 0
21 #include <linux/build_bug.h>
22 #include <linux/cache.h>
23 #include <linux/init.h>
24 #include <linux/stddef.h>
25 #include <linux/string.h>
26 #include <linux/thread_info.h>
28 #include <vdso/processor.h>
30 #include <asm/alternative.h>
31 #include <asm/cpufeature.h>
32 #include <asm/hw_breakpoint.h>
33 #include <asm/kasan.h>
35 #include <asm/pgtable-hwdef.h>
36 #include <asm/pointer_auth.h>
37 #include <asm/ptrace.h>
38 #include <asm/spectre.h>
39 #include <asm/types.h>
42 * TASK_SIZE - the maximum size of a user space task.
43 * TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
46 #define DEFAULT_MAP_WINDOW_64 (UL(1) << VA_BITS_MIN)
47 #define TASK_SIZE_64 (UL(1) << vabits_actual)
48 #define TASK_SIZE_MAX (UL(1) << VA_BITS)
51 #if defined(CONFIG_ARM64_64K_PAGES) && defined(CONFIG_KUSER_HELPERS)
53 * With CONFIG_ARM64_64K_PAGES enabled, the last page is occupied
54 * by the compat vectors page.
56 #define TASK_SIZE_32 UL(0x100000000)
58 #define TASK_SIZE_32 (UL(0x100000000) - PAGE_SIZE)
59 #endif /* CONFIG_ARM64_64K_PAGES */
60 #define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
61 TASK_SIZE_32 : TASK_SIZE_64)
62 #define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
63 TASK_SIZE_32 : TASK_SIZE_64)
64 #define DEFAULT_MAP_WINDOW (test_thread_flag(TIF_32BIT) ? \
65 TASK_SIZE_32 : DEFAULT_MAP_WINDOW_64)
67 #define TASK_SIZE TASK_SIZE_64
68 #define DEFAULT_MAP_WINDOW DEFAULT_MAP_WINDOW_64
69 #endif /* CONFIG_COMPAT */
71 #ifdef CONFIG_ARM64_FORCE_52BIT
72 #define STACK_TOP_MAX TASK_SIZE_64
73 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4))
75 #define STACK_TOP_MAX DEFAULT_MAP_WINDOW_64
76 #define TASK_UNMAPPED_BASE (PAGE_ALIGN(DEFAULT_MAP_WINDOW / 4))
77 #endif /* CONFIG_ARM64_FORCE_52BIT */
80 #define AARCH32_VECTORS_BASE 0xffff0000
81 #define STACK_TOP (test_thread_flag(TIF_32BIT) ? \
82 AARCH32_VECTORS_BASE : STACK_TOP_MAX)
84 #define STACK_TOP STACK_TOP_MAX
85 #endif /* CONFIG_COMPAT */
87 #ifndef CONFIG_ARM64_FORCE_52BIT
88 #define arch_get_mmap_end(addr) ((addr > DEFAULT_MAP_WINDOW) ? TASK_SIZE :\
91 #define arch_get_mmap_base(addr, base) ((addr > DEFAULT_MAP_WINDOW) ? \
92 base + TASK_SIZE - DEFAULT_MAP_WINDOW :\
94 #endif /* CONFIG_ARM64_FORCE_52BIT */
96 extern phys_addr_t arm64_dma_phys_limit;
97 #define ARCH_LOW_ADDRESS_LIMIT (arm64_dma_phys_limit - 1)
100 #ifdef CONFIG_HAVE_HW_BREAKPOINT
101 /* Have we suspended stepping by a debugger? */
103 /* Allow breakpoints and watchpoints to be disabled for this thread. */
106 /* Hardware breakpoints pinned to this task. */
107 struct perf_event *hbp_break[ARM_MAX_BRP];
108 struct perf_event *hbp_watch[ARM_MAX_WRP];
128 struct thread_struct {
129 struct cpu_context cpu_context; /* cpu context */
132 * Whitelisted fields for hardened usercopy:
133 * Maintainers must ensure manually that this contains no
137 unsigned long tp_value; /* TLS register */
138 unsigned long tp2_value;
139 struct user_fpsimd_state fpsimd_state;
142 unsigned int fpsimd_cpu;
143 void *sve_state; /* SVE registers, if any */
144 unsigned int sve_vl; /* SVE vector length */
145 unsigned int sve_vl_onexec; /* SVE vl after next exec */
146 unsigned long fault_address; /* fault info */
147 unsigned long fault_code; /* ESR_EL1 value */
148 struct debug_info debug; /* debugging */
149 #ifdef CONFIG_ARM64_PTR_AUTH
150 struct ptrauth_keys_user keys_user;
151 struct ptrauth_keys_kernel keys_kernel;
153 #ifdef CONFIG_ARM64_MTE
159 static inline void arch_thread_struct_whitelist(unsigned long *offset,
162 /* Verify that there is no padding among the whitelisted fields: */
163 BUILD_BUG_ON(sizeof_field(struct thread_struct, uw) !=
164 sizeof_field(struct thread_struct, uw.tp_value) +
165 sizeof_field(struct thread_struct, uw.tp2_value) +
166 sizeof_field(struct thread_struct, uw.fpsimd_state));
168 *offset = offsetof(struct thread_struct, uw);
169 *size = sizeof_field(struct thread_struct, uw);
173 #define task_user_tls(t) \
175 unsigned long *__tls; \
176 if (is_compat_thread(task_thread_info(t))) \
177 __tls = &(t)->thread.uw.tp2_value; \
179 __tls = &(t)->thread.uw.tp_value; \
183 #define task_user_tls(t) (&(t)->thread.uw.tp_value)
186 /* Sync TPIDR_EL0 back to thread_struct for current */
187 void tls_preserve_current_state(void);
189 #define INIT_THREAD { \
190 .fpsimd_cpu = NR_CPUS, \
193 static inline void start_thread_common(struct pt_regs *regs, unsigned long pc)
195 memset(regs, 0, sizeof(*regs));
196 forget_syscall(regs);
199 if (system_uses_irq_prio_masking())
200 regs->pmr_save = GIC_PRIO_IRQON;
203 static inline void start_thread(struct pt_regs *regs, unsigned long pc,
206 start_thread_common(regs, pc);
207 regs->pstate = PSR_MODE_EL0t;
208 spectre_v4_enable_task_mitigation(current);
213 static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc,
216 start_thread_common(regs, pc);
217 regs->pstate = PSR_AA32_MODE_USR;
219 regs->pstate |= PSR_AA32_T_BIT;
222 regs->pstate |= PSR_AA32_E_BIT;
225 spectre_v4_enable_task_mitigation(current);
226 regs->compat_sp = sp;
230 static inline bool is_ttbr0_addr(unsigned long addr)
232 /* entry assembly clears tags for TTBR0 addrs */
233 return addr < TASK_SIZE;
236 static inline bool is_ttbr1_addr(unsigned long addr)
238 /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */
239 return arch_kasan_reset_tag(addr) >= PAGE_OFFSET;
242 /* Forward declaration, a strange C thing */
245 /* Free all resources held by a thread. */
246 extern void release_thread(struct task_struct *);
248 unsigned long get_wchan(struct task_struct *p);
250 /* Thread switching */
251 extern struct task_struct *cpu_switch_to(struct task_struct *prev,
252 struct task_struct *next);
254 #define task_pt_regs(p) \
255 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1)
257 #define KSTK_EIP(tsk) ((unsigned long)task_pt_regs(tsk)->pc)
258 #define KSTK_ESP(tsk) user_stack_pointer(task_pt_regs(tsk))
261 * Prefetching support
263 #define ARCH_HAS_PREFETCH
264 static inline void prefetch(const void *ptr)
266 asm volatile("prfm pldl1keep, %a0\n" : : "p" (ptr));
269 #define ARCH_HAS_PREFETCHW
270 static inline void prefetchw(const void *ptr)
272 asm volatile("prfm pstl1keep, %a0\n" : : "p" (ptr));
275 #define ARCH_HAS_SPINLOCK_PREFETCH
276 static inline void spin_lock_prefetch(const void *ptr)
278 asm volatile(ARM64_LSE_ATOMIC_INSN(
279 "prfm pstl1strm, %a0",
280 "nop") : : "p" (ptr));
283 extern unsigned long __ro_after_init signal_minsigstksz; /* sigframe size */
284 extern void __init minsigstksz_setup(void);
287 * Not at the top of the file due to a direct #include cycle between
288 * <asm/fpsimd.h> and <asm/processor.h>. Deferring this #include
289 * ensures that contents of processor.h are visible to fpsimd.h even if
290 * processor.h is included first.
292 * These prctl helpers are the only things in this file that require
293 * fpsimd.h. The core code expects them to be in this header.
295 #include <asm/fpsimd.h>
297 /* Userspace interface for PR_SVE_{SET,GET}_VL prctl()s: */
298 #define SVE_SET_VL(arg) sve_set_current_vl(arg)
299 #define SVE_GET_VL() sve_get_current_vl()
301 /* PR_PAC_RESET_KEYS prctl */
302 #define PAC_RESET_KEYS(tsk, arg) ptrauth_prctl_reset_keys(tsk, arg)
304 #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI
305 /* PR_{SET,GET}_TAGGED_ADDR_CTRL prctl */
306 long set_tagged_addr_ctrl(struct task_struct *task, unsigned long arg);
307 long get_tagged_addr_ctrl(struct task_struct *task);
308 #define SET_TAGGED_ADDR_CTRL(arg) set_tagged_addr_ctrl(current, arg)
309 #define GET_TAGGED_ADDR_CTRL() get_tagged_addr_ctrl(current)
313 * For CONFIG_GCC_PLUGIN_STACKLEAK
315 * These need to be macros because otherwise we get stuck in a nightmare
316 * of header definitions for the use of task_stack_page.
319 #define current_top_of_stack() \
321 struct stack_info _info; \
322 BUG_ON(!on_accessible_stack(current, current_stack_pointer, &_info)); \
325 #define on_thread_stack() (on_task_stack(current, current_stack_pointer, NULL))
327 #endif /* __ASSEMBLY__ */
328 #endif /* __ASM_PROCESSOR_H */