From 0fdbb7d2c1ecb761b985b176b9bb159d483d9514 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 12 Sep 2021 19:25:22 -0700 Subject: [PATCH] accel/tcg: Split out adjust_signal_pc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Split out a function to adjust the raw signal pc into a value that could be passed to cpu_restore_state. Reviewed-by: Warner Losh Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Richard Henderson --- v2: Adjust pc in place; return MMUAccessType. --- accel/tcg/user-exec.c | 41 +++++++++++++++++++++++++---------------- include/exec/exec-all.h | 10 ++++++++++ 2 files changed, 35 insertions(+), 16 deletions(-) diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c index e6bb29b42d..c02d509ec6 100644 --- a/accel/tcg/user-exec.c +++ b/accel/tcg/user-exec.c @@ -57,18 +57,11 @@ static void QEMU_NORETURN cpu_exit_tb_from_sighandler(CPUState *cpu, cpu_loop_exit_noexc(cpu); } -/* 'pc' is the host PC at which the exception was raised. 'address' is - the effective address of the memory exception. 'is_write' is 1 if a - write caused the exception and otherwise 0'. 'old_set' is the - signal set which should be restored */ -static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, - int is_write, sigset_t *old_set) +/* + * Adjust the pc to pass to cpu_restore_state; return the memop type. + */ +MMUAccessType adjust_signal_pc(uintptr_t *pc, bool is_write) { - CPUState *cpu = current_cpu; - CPUClass *cc; - unsigned long address = (unsigned long)info->si_addr; - MMUAccessType access_type = is_write ? MMU_DATA_STORE : MMU_DATA_LOAD; - switch (helper_retaddr) { default: /* @@ -77,7 +70,7 @@ static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, * pointer into the generated code that will unwind to the * correct guest pc. */ - pc = helper_retaddr; + *pc = helper_retaddr; break; case 0: @@ -97,7 +90,7 @@ static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, * Therefore, adjust to compensate for what will be done later * by cpu_restore_state_from_tb. */ - pc += GETPC_ADJ; + *pc += GETPC_ADJ; break; case 1: @@ -113,12 +106,28 @@ static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, * * Like tb_gen_code, release the memory lock before cpu_loop_exit. */ - pc = 0; - access_type = MMU_INST_FETCH; mmap_unlock(); - break; + *pc = 0; + return MMU_INST_FETCH; } + return is_write ? MMU_DATA_STORE : MMU_DATA_LOAD; +} + +/* + * 'pc' is the host PC at which the exception was raised. + * 'address' is the effective address of the memory exception. + * 'is_write' is 1 if a write caused the exception and otherwise 0. + * 'old_set' is the signal set which should be restored. + */ +static inline int handle_cpu_signal(uintptr_t pc, siginfo_t *info, + int is_write, sigset_t *old_set) +{ + CPUState *cpu = current_cpu; + CPUClass *cc; + unsigned long address = (unsigned long)info->si_addr; + MMUAccessType access_type = adjust_signal_pc(&pc, is_write); + /* For synchronous signals we expect to be coming from the vCPU * thread (so current_cpu should be valid) and either from running * code or during translation which can fault as we cross pages. diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h index 9d5987ba04..e54f8e5d65 100644 --- a/include/exec/exec-all.h +++ b/include/exec/exec-all.h @@ -663,6 +663,16 @@ static inline tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, return addr; } +/** + * adjust_signal_pc: + * @pc: raw pc from the host signal ucontext_t. + * @is_write: host memory operation was write, or read-modify-write. + * + * Alter @pc as required for unwinding. Return the type of the + * guest memory access -- host reads may be for guest execution. + */ +MMUAccessType adjust_signal_pc(uintptr_t *pc, bool is_write); + /** * cpu_signal_handler * @signum: host signal number