 9940799bde
			
		
	
	
		9940799bde
		
	
	
	
	
		
			
			Do not directly access ucontext_t as the third signal parameter. This is preparation for a sparc64 fix. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
		
			
				
	
	
		
			88 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * host-signal.h: signal info dependent on the host architecture
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|  *
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|  * Copyright (c) 2003-2005 Fabrice Bellard
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|  * Copyright (c) 2021 Linaro Limited
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|  *
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|  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
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|  * See the COPYING file in the top-level directory.
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|  */
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| 
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| #ifndef AARCH64_HOST_SIGNAL_H
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| #define AARCH64_HOST_SIGNAL_H
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| 
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| /* The third argument to a SA_SIGINFO handler is ucontext_t. */
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| typedef ucontext_t host_sigcontext;
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| 
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| /* Pre-3.16 kernel headers don't have these, so provide fallback definitions */
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| #ifndef ESR_MAGIC
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| #define ESR_MAGIC 0x45535201
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| struct esr_context {
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|     struct _aarch64_ctx head;
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|     uint64_t esr;
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| };
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| #endif
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| 
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| static inline struct _aarch64_ctx *first_ctx(host_sigcontext *uc)
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| {
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|     return (struct _aarch64_ctx *)&uc->uc_mcontext.__reserved;
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| }
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| 
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| static inline struct _aarch64_ctx *next_ctx(struct _aarch64_ctx *hdr)
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| {
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|     return (struct _aarch64_ctx *)((char *)hdr + hdr->size);
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| }
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| 
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| static inline uintptr_t host_signal_pc(host_sigcontext *uc)
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| {
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|     return uc->uc_mcontext.pc;
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| }
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| 
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| static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
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| {
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|     uc->uc_mcontext.pc = pc;
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| }
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| 
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| static inline void *host_signal_mask(host_sigcontext *uc)
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| {
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|     return &uc->uc_sigmask;
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| }
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| 
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| static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
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| {
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|     struct _aarch64_ctx *hdr;
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|     uint32_t insn;
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| 
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|     /* Find the esr_context, which has the WnR bit in it */
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|     for (hdr = first_ctx(uc); hdr->magic; hdr = next_ctx(hdr)) {
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|         if (hdr->magic == ESR_MAGIC) {
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|             struct esr_context const *ec = (struct esr_context const *)hdr;
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|             uint64_t esr = ec->esr;
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| 
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|             /* For data aborts ESR.EC is 0b10010x: then bit 6 is the WnR bit */
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|             return extract32(esr, 27, 5) == 0x12 && extract32(esr, 6, 1) == 1;
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|         }
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|     }
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| 
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|     /*
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|      * Fall back to parsing instructions; will only be needed
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|      * for really ancient (pre-3.16) kernels.
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|      */
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|     insn = *(uint32_t *)host_signal_pc(uc);
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| 
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|     return (insn & 0xbfff0000) == 0x0c000000   /* C3.3.1 */
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|         || (insn & 0xbfe00000) == 0x0c800000   /* C3.3.2 */
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|         || (insn & 0xbfdf0000) == 0x0d000000   /* C3.3.3 */
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|         || (insn & 0xbfc00000) == 0x0d800000   /* C3.3.4 */
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|         || (insn & 0x3f400000) == 0x08000000   /* C3.3.6 */
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|         || (insn & 0x3bc00000) == 0x39000000   /* C3.3.13 */
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|         || (insn & 0x3fc00000) == 0x3d800000   /* ... 128bit */
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|         /* Ignore bits 10, 11 & 21, controlling indexing.  */
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|         || (insn & 0x3bc00000) == 0x38000000   /* C3.3.8-12 */
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|         || (insn & 0x3fe00000) == 0x3c800000   /* ... 128bit */
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|         /* Ignore bits 23 & 24, controlling indexing.  */
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|         || (insn & 0x3a400000) == 0x28000000; /* C3.3.7,14-16 */
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| }
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| 
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| #endif
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