host-signal.h (2719B)
1 /* 2 * host-signal.h: signal info dependent on the host architecture 3 * 4 * Copyright (c) 2003-2005 Fabrice Bellard 5 * Copyright (c) 2021 Linaro Limited 6 * 7 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. 8 * See the COPYING file in the top-level directory. 9 */ 10 11 #ifndef AARCH64_HOST_SIGNAL_H 12 #define AARCH64_HOST_SIGNAL_H 13 14 /* The third argument to a SA_SIGINFO handler is ucontext_t. */ 15 typedef ucontext_t host_sigcontext; 16 17 /* Pre-3.16 kernel headers don't have these, so provide fallback definitions */ 18 #ifndef ESR_MAGIC 19 #define ESR_MAGIC 0x45535201 20 struct esr_context { 21 struct _aarch64_ctx head; 22 uint64_t esr; 23 }; 24 #endif 25 26 static inline struct _aarch64_ctx *first_ctx(host_sigcontext *uc) 27 { 28 return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved; 29 } 30 31 static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr) 32 { 33 return (struct _aarch64_ctx *)((char *)hdr + hdr->size); 34 } 35 36 static inline uintptr_t host_signal_pc(host_sigcontext *uc) 37 { 38 return uc->uc_mcontext.pc; 39 } 40 41 static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc) 42 { 43 uc->uc_mcontext.pc = pc; 44 } 45 46 static inline void *host_signal_mask(host_sigcontext *uc) 47 { 48 return &uc->uc_sigmask; 49 } 50 51 static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc) 52 { 53 struct _aarch64_ctx *hdr; 54 uint32_t insn; 55 56 /* Find the esr_context, which has the WnR bit in it */ 57 for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) { 58 if (hdr->magic == ESR_MAGIC) { 59 struct esr_context const *ec = (struct esr_context const *)hdr; 60 uint64_t esr = ec->esr; 61 62 /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */ 63 return extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1; 64 } 65 } 66 67 /* 68 * Fall back to parsing instructions; will only be needed 69 * for really ancient (pre-3.16) kernels. 70 */ 71 insn = *(uint32_t *)host_signal_pc(uc); 72 73 return (insn & 0xbfff0000) == 0x0c000000 /* C3.3.1 */ 74 || (insn & 0xbfe00000) == 0x0c800000 /* C3.3.2 */ 75 || (insn & 0xbfdf0000) == 0x0d000000 /* C3.3.3 */ 76 || (insn & 0xbfc00000) == 0x0d800000 /* C3.3.4 */ 77 || (insn & 0x3f400000) == 0x08000000 /* C3.3.6 */ 78 || (insn & 0x3bc00000) == 0x39000000 /* C3.3.13 */ 79 || (insn & 0x3fc00000) == 0x3d800000 /* ... 128bit */ 80 /* Ignore bits 10, 11 & 21, controlling indexing. */ 81 || (insn & 0x3bc00000) == 0x38000000 /* C3.3.8-12 */ 82 || (insn & 0x3fe00000) == 0x3c800000 /* ... 128bit */ 83 /* Ignore bits 23 & 24, controlling indexing. */ 84 || (insn & 0x3a400000) == 0x28000000; /* C3.3.7,14-16 */ 85 } 86 87 #endif