From cf5f42fd07fa7ca4cfcf940093ef2506f990d1db Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 17 Sep 2021 10:39:15 -0700 Subject: linux-user/host/aarch64: Populate host_signal.h Split host_signal_pc and host_signal_write out of user-exec.c. Drop the *BSD code, to be re-created under bsd-user/ later. Reviewed-by: Warner Losh Signed-off-by: Richard Henderson --- linux-user/host/aarch64/host-signal.h | 75 ++++++++++++++++++++++++++++++++++- 1 file changed, 74 insertions(+), 1 deletion(-) (limited to 'linux-user/host/aarch64') diff --git a/linux-user/host/aarch64/host-signal.h b/linux-user/host/aarch64/host-signal.h index f4b4d65031..0c0b08383a 100644 --- a/linux-user/host/aarch64/host-signal.h +++ b/linux-user/host/aarch64/host-signal.h @@ -1 +1,74 @@ -#define HOST_SIGNAL_PLACEHOLDER +/* + * host-signal.h: signal info dependent on the host architecture + * + * Copyright (c) 2003-2005 Fabrice Bellard + * Copyright (c) 2021 Linaro Limited + * + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef AARCH64_HOST_SIGNAL_H +#define AARCH64_HOST_SIGNAL_H + +/* Pre-3.16 kernel headers don't have these, so provide fallback definitions */ +#ifndef ESR_MAGIC +#define ESR_MAGIC 0x45535201 +struct esr_context { + struct _aarch64_ctx head; + uint64_t esr; +}; +#endif + +static inline struct _aarch64_ctx *first_ctx(ucontext_t *uc) +{ + return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved; +} + +static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr) +{ + return (struct _aarch64_ctx *)((char *)hdr + hdr->size); +} + +static inline uintptr_t host_signal_pc(ucontext_t *uc) +{ + return uc->uc_mcontext.pc; +} + +static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc) +{ + struct _aarch64_ctx *hdr; + uint32_t insn; + + /* Find the esr_context, which has the WnR bit in it */ + for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) { + if (hdr->magic == ESR_MAGIC) { + struct esr_context const *ec = (struct esr_context const *)hdr; + uint64_t esr = ec->esr; + + /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */ + return extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1; + } + } + + /* + * Fall back to parsing instructions; will only be needed + * for really ancient (pre-3.16) kernels. + */ + insn = *(uint32_t *)host_signal_pc(uc); + + return (insn & 0xbfff0000) == 0x0c000000 /* C3.3.1 */ + || (insn & 0xbfe00000) == 0x0c800000 /* C3.3.2 */ + || (insn & 0xbfdf0000) == 0x0d000000 /* C3.3.3 */ + || (insn & 0xbfc00000) == 0x0d800000 /* C3.3.4 */ + || (insn & 0x3f400000) == 0x08000000 /* C3.3.6 */ + || (insn & 0x3bc00000) == 0x39000000 /* C3.3.13 */ + || (insn & 0x3fc00000) == 0x3d800000 /* ... 128bit */ + /* Ignore bits 10, 11 & 21, controlling indexing. */ + || (insn & 0x3bc00000) == 0x38000000 /* C3.3.8-12 */ + || (insn & 0x3fe00000) == 0x3c800000 /* ... 128bit */ + /* Ignore bits 23 & 24, controlling indexing. */ + || (insn & 0x3a400000) == 0x28000000; /* C3.3.7,14-16 */ +} + +#endif -- cgit v1.2.3