accel/tcg: Split out adjust_signal_pc

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 <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
v2: Adjust pc in place; return MMUAccessType.
This commit is contained in:
Richard Henderson 2021-09-12 19:25:22 -07:00
parent dd61b91c08
commit 0fdbb7d2c1
2 changed files with 35 additions and 16 deletions

View file

@ -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.

View file

@ -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