ptrace.h 9.4 KB

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  1. /* SPDX-License-Identifier: GPL-2.0-only */
  2. /*
  3. * Based on arch/arm/include/asm/ptrace.h
  4. *
  5. * Copyright (C) 1996-2003 Russell King
  6. * Copyright (C) 2012 ARM Ltd.
  7. */
  8. #ifndef __ASM_PTRACE_H
  9. #define __ASM_PTRACE_H
  10. #include <asm/cpufeature.h>
  11. #include <uapi/asm/ptrace.h>
  12. /* Current Exception Level values, as contained in CurrentEL */
  13. #define CurrentEL_EL1 (1 << 2)
  14. #define CurrentEL_EL2 (2 << 2)
  15. #define INIT_PSTATE_EL1 \
  16. (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT | PSR_MODE_EL1h)
  17. #define INIT_PSTATE_EL2 \
  18. (PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT | PSR_MODE_EL2h)
  19. #include <linux/irqchip/arm-gic-v3-prio.h>
  20. #define GIC_PRIO_IRQON GICV3_PRIO_UNMASKED
  21. #define GIC_PRIO_IRQOFF GICV3_PRIO_IRQ
  22. #define GIC_PRIO_PSR_I_SET GICV3_PRIO_PSR_I_SET
  23. /* Additional SPSR bits not exposed in the UABI */
  24. #define PSR_MODE_THREAD_BIT (1 << 0)
  25. #define PSR_IL_BIT (1 << 20)
  26. /* AArch32-specific ptrace requests */
  27. #define COMPAT_PTRACE_GETREGS 12
  28. #define COMPAT_PTRACE_SETREGS 13
  29. #define COMPAT_PTRACE_GET_THREAD_AREA 22
  30. #define COMPAT_PTRACE_SET_SYSCALL 23
  31. #define COMPAT_PTRACE_GETVFPREGS 27
  32. #define COMPAT_PTRACE_SETVFPREGS 28
  33. #define COMPAT_PTRACE_GETHBPREGS 29
  34. #define COMPAT_PTRACE_SETHBPREGS 30
  35. /* SPSR_ELx bits for exceptions taken from AArch32 */
  36. #define PSR_AA32_MODE_MASK 0x0000001f
  37. #define PSR_AA32_MODE_USR 0x00000010
  38. #define PSR_AA32_MODE_FIQ 0x00000011
  39. #define PSR_AA32_MODE_IRQ 0x00000012
  40. #define PSR_AA32_MODE_SVC 0x00000013
  41. #define PSR_AA32_MODE_ABT 0x00000017
  42. #define PSR_AA32_MODE_HYP 0x0000001a
  43. #define PSR_AA32_MODE_UND 0x0000001b
  44. #define PSR_AA32_MODE_SYS 0x0000001f
  45. #define PSR_AA32_T_BIT 0x00000020
  46. #define PSR_AA32_F_BIT 0x00000040
  47. #define PSR_AA32_I_BIT 0x00000080
  48. #define PSR_AA32_A_BIT 0x00000100
  49. #define PSR_AA32_E_BIT 0x00000200
  50. #define PSR_AA32_PAN_BIT 0x00400000
  51. #define PSR_AA32_SSBS_BIT 0x00800000
  52. #define PSR_AA32_DIT_BIT 0x01000000
  53. #define PSR_AA32_Q_BIT 0x08000000
  54. #define PSR_AA32_V_BIT 0x10000000
  55. #define PSR_AA32_C_BIT 0x20000000
  56. #define PSR_AA32_Z_BIT 0x40000000
  57. #define PSR_AA32_N_BIT 0x80000000
  58. #define PSR_AA32_IT_MASK 0x0600fc00 /* If-Then execution state mask */
  59. #define PSR_AA32_GE_MASK 0x000f0000
  60. #ifdef CONFIG_CPU_BIG_ENDIAN
  61. #define PSR_AA32_ENDSTATE PSR_AA32_E_BIT
  62. #else
  63. #define PSR_AA32_ENDSTATE 0
  64. #endif
  65. /* AArch32 CPSR bits, as seen in AArch32 */
  66. #define COMPAT_PSR_DIT_BIT 0x00200000
  67. /*
  68. * These are 'magic' values for PTRACE_PEEKUSR that return info about where a
  69. * process is located in memory.
  70. */
  71. #define COMPAT_PT_TEXT_ADDR 0x10000
  72. #define COMPAT_PT_DATA_ADDR 0x10004
  73. #define COMPAT_PT_TEXT_END_ADDR 0x10008
  74. /*
  75. * If pt_regs.syscallno == NO_SYSCALL, then the thread is not executing
  76. * a syscall -- i.e., its most recent entry into the kernel from
  77. * userspace was not via SVC, or otherwise a tracer cancelled the syscall.
  78. *
  79. * This must have the value -1, for ABI compatibility with ptrace etc.
  80. */
  81. #define NO_SYSCALL (-1)
  82. #ifndef __ASSEMBLY__
  83. #include <linux/bug.h>
  84. #include <linux/types.h>
  85. /* sizeof(struct user) for AArch32 */
  86. #define COMPAT_USER_SZ 296
  87. /* Architecturally defined mapping between AArch32 and AArch64 registers */
  88. #define compat_usr(x) regs[(x)]
  89. #define compat_fp regs[11]
  90. #define compat_sp regs[13]
  91. #define compat_lr regs[14]
  92. #define compat_sp_hyp regs[15]
  93. #define compat_lr_irq regs[16]
  94. #define compat_sp_irq regs[17]
  95. #define compat_lr_svc regs[18]
  96. #define compat_sp_svc regs[19]
  97. #define compat_lr_abt regs[20]
  98. #define compat_sp_abt regs[21]
  99. #define compat_lr_und regs[22]
  100. #define compat_sp_und regs[23]
  101. #define compat_r8_fiq regs[24]
  102. #define compat_r9_fiq regs[25]
  103. #define compat_r10_fiq regs[26]
  104. #define compat_r11_fiq regs[27]
  105. #define compat_r12_fiq regs[28]
  106. #define compat_sp_fiq regs[29]
  107. #define compat_lr_fiq regs[30]
  108. static inline unsigned long compat_psr_to_pstate(const unsigned long psr)
  109. {
  110. unsigned long pstate;
  111. pstate = psr & ~COMPAT_PSR_DIT_BIT;
  112. if (psr & COMPAT_PSR_DIT_BIT)
  113. pstate |= PSR_AA32_DIT_BIT;
  114. return pstate;
  115. }
  116. static inline unsigned long pstate_to_compat_psr(const unsigned long pstate)
  117. {
  118. unsigned long psr;
  119. psr = pstate & ~PSR_AA32_DIT_BIT;
  120. if (pstate & PSR_AA32_DIT_BIT)
  121. psr |= COMPAT_PSR_DIT_BIT;
  122. return psr;
  123. }
  124. /*
  125. * This struct defines the way the registers are stored on the stack during an
  126. * exception. Note that sizeof(struct pt_regs) has to be a multiple of 16 (for
  127. * stack alignment). struct user_pt_regs must form a prefix of struct pt_regs.
  128. */
  129. struct pt_regs {
  130. union {
  131. struct user_pt_regs user_regs;
  132. struct {
  133. u64 regs[31];
  134. u64 sp;
  135. u64 pc;
  136. u64 pstate;
  137. };
  138. };
  139. u64 orig_x0;
  140. #ifdef __AARCH64EB__
  141. u32 unused2;
  142. s32 syscallno;
  143. #else
  144. s32 syscallno;
  145. u32 unused2;
  146. #endif
  147. u64 sdei_ttbr1;
  148. /* Only valid when ARM64_HAS_GIC_PRIO_MASKING is enabled. */
  149. u64 pmr_save;
  150. u64 stackframe[2];
  151. /* Only valid for some EL1 exceptions. */
  152. u64 lockdep_hardirqs;
  153. u64 exit_rcu;
  154. };
  155. static inline bool in_syscall(struct pt_regs const *regs)
  156. {
  157. return regs->syscallno != NO_SYSCALL;
  158. }
  159. static inline void forget_syscall(struct pt_regs *regs)
  160. {
  161. regs->syscallno = NO_SYSCALL;
  162. }
  163. #define MAX_REG_OFFSET offsetof(struct pt_regs, pstate)
  164. #define arch_has_single_step() (1)
  165. #ifdef CONFIG_COMPAT
  166. #define compat_thumb_mode(regs) \
  167. (((regs)->pstate & PSR_AA32_T_BIT))
  168. #else
  169. #define compat_thumb_mode(regs) (0)
  170. #endif
  171. #define user_mode(regs) \
  172. (((regs)->pstate & PSR_MODE_MASK) == PSR_MODE_EL0t)
  173. #define compat_user_mode(regs) \
  174. (((regs)->pstate & (PSR_MODE32_BIT | PSR_MODE_MASK)) == \
  175. (PSR_MODE32_BIT | PSR_MODE_EL0t))
  176. #define processor_mode(regs) \
  177. ((regs)->pstate & PSR_MODE_MASK)
  178. #define irqs_priority_unmasked(regs) \
  179. (system_uses_irq_prio_masking() ? \
  180. (regs)->pmr_save == GIC_PRIO_IRQON : \
  181. true)
  182. #define interrupts_enabled(regs) \
  183. (!((regs)->pstate & PSR_I_BIT) && irqs_priority_unmasked(regs))
  184. #define fast_interrupts_enabled(regs) \
  185. (!((regs)->pstate & PSR_F_BIT))
  186. static inline unsigned long user_stack_pointer(struct pt_regs *regs)
  187. {
  188. if (compat_user_mode(regs))
  189. return regs->compat_sp;
  190. return regs->sp;
  191. }
  192. extern int regs_query_register_offset(const char *name);
  193. extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
  194. unsigned int n);
  195. /**
  196. * regs_get_register() - get register value from its offset
  197. * @regs: pt_regs from which register value is gotten
  198. * @offset: offset of the register.
  199. *
  200. * regs_get_register returns the value of a register whose offset from @regs.
  201. * The @offset is the offset of the register in struct pt_regs.
  202. * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
  203. */
  204. static inline u64 regs_get_register(struct pt_regs *regs, unsigned int offset)
  205. {
  206. u64 val = 0;
  207. WARN_ON(offset & 7);
  208. offset >>= 3;
  209. switch (offset) {
  210. case 0 ... 30:
  211. val = regs->regs[offset];
  212. break;
  213. case offsetof(struct pt_regs, sp) >> 3:
  214. val = regs->sp;
  215. break;
  216. case offsetof(struct pt_regs, pc) >> 3:
  217. val = regs->pc;
  218. break;
  219. case offsetof(struct pt_regs, pstate) >> 3:
  220. val = regs->pstate;
  221. break;
  222. default:
  223. val = 0;
  224. }
  225. return val;
  226. }
  227. /*
  228. * Read a register given an architectural register index r.
  229. * This handles the common case where 31 means XZR, not SP.
  230. */
  231. static inline unsigned long pt_regs_read_reg(const struct pt_regs *regs, int r)
  232. {
  233. return (r == 31) ? 0 : regs->regs[r];
  234. }
  235. /*
  236. * Write a register given an architectural register index r.
  237. * This handles the common case where 31 means XZR, not SP.
  238. */
  239. static inline void pt_regs_write_reg(struct pt_regs *regs, int r,
  240. unsigned long val)
  241. {
  242. if (r != 31)
  243. regs->regs[r] = val;
  244. }
  245. /* Valid only for Kernel mode traps. */
  246. static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
  247. {
  248. return regs->sp;
  249. }
  250. static inline unsigned long regs_return_value(struct pt_regs *regs)
  251. {
  252. unsigned long val = regs->regs[0];
  253. /*
  254. * Audit currently uses regs_return_value() instead of
  255. * syscall_get_return_value(). Apply the same sign-extension here until
  256. * audit is updated to use syscall_get_return_value().
  257. */
  258. if (compat_user_mode(regs))
  259. val = sign_extend64(val, 31);
  260. return val;
  261. }
  262. static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc)
  263. {
  264. regs->regs[0] = rc;
  265. }
  266. /**
  267. * regs_get_kernel_argument() - get Nth function argument in kernel
  268. * @regs: pt_regs of that context
  269. * @n: function argument number (start from 0)
  270. *
  271. * regs_get_argument() returns @n th argument of the function call.
  272. *
  273. * Note that this chooses the most likely register mapping. In very rare
  274. * cases this may not return correct data, for example, if one of the
  275. * function parameters is 16 bytes or bigger. In such cases, we cannot
  276. * get access the parameter correctly and the register assignment of
  277. * subsequent parameters will be shifted.
  278. */
  279. static inline unsigned long regs_get_kernel_argument(struct pt_regs *regs,
  280. unsigned int n)
  281. {
  282. #define NR_REG_ARGUMENTS 8
  283. if (n < NR_REG_ARGUMENTS)
  284. return pt_regs_read_reg(regs, n);
  285. return 0;
  286. }
  287. /* We must avoid circular header include via sched.h */
  288. struct task_struct;
  289. int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task);
  290. static inline unsigned long instruction_pointer(struct pt_regs *regs)
  291. {
  292. return regs->pc;
  293. }
  294. static inline void instruction_pointer_set(struct pt_regs *regs,
  295. unsigned long val)
  296. {
  297. regs->pc = val;
  298. }
  299. static inline unsigned long frame_pointer(struct pt_regs *regs)
  300. {
  301. return regs->regs[29];
  302. }
  303. #define procedure_link_pointer(regs) ((regs)->regs[30])
  304. static inline void procedure_link_pointer_set(struct pt_regs *regs,
  305. unsigned long val)
  306. {
  307. procedure_link_pointer(regs) = val;
  308. }
  309. extern unsigned long profile_pc(struct pt_regs *regs);
  310. #endif /* __ASSEMBLY__ */
  311. #endif