[PATCH 3/8] linux-user: Pass CPUArchState to do_sigaltstack

[Richard Henderson]

Now that we have exactly one call, it's easy to pass
in env instead of passing in the sp value.
Use target_save_altstack, which required env.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/qemu.h    |  3 ++-
 linux-user/signal.c  | 11 ++++-------
 linux-user/syscall.c |  3 +--
 3 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index 74e06e7121..3b0b6b75fe 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -432,7 +432,8 @@ int target_to_host_signal(int sig);
 int host_to_target_signal(int sig);
 long do_sigreturn(CPUArchState *env);
 long do_rt_sigreturn(CPUArchState *env);
-abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
+abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr,
+                        CPUArchState *env);
 int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
 abi_long do_swapcontext(CPUArchState *env, abi_ulong uold_ctx,
                         abi_ulong unew_ctx, abi_long ctx_size);
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 306f3edec5..83891f7c47 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -800,21 +800,18 @@ static void host_signal_handler(int host_signum, 
siginfo_t *info,
 
 /* do_sigaltstack() returns target values and errnos. */
 /* compare linux/kernel/signal.c:do_sigaltstack() */
-abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp)
+abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr,
+                        CPUArchState *env)
 {
     target_stack_t oss, *uoss = NULL;
     abi_long ret = -TARGET_EFAULT;
 
     if (uoss_addr) {
-        TaskState *ts = (TaskState *)thread_cpu->opaque;
-
         /* Verify writability now, but do not alter user memory yet. */
         if (!lock_user_struct(VERIFY_WRITE, uoss, uoss_addr, 0)) {
             goto out;
         }
-        __put_user(ts->sigaltstack_used.ss_sp, &oss.ss_sp);
-        __put_user(ts->sigaltstack_used.ss_size, &oss.ss_size);
-        __put_user(sas_ss_flags(sp), &oss.ss_flags);
+        target_save_altstack(&oss, env);
     }
 
     if (uss_addr) {
@@ -823,7 +820,7 @@ abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong 
uoss_addr, abi_ulong sp)
         if (!lock_user_struct(VERIFY_READ, uss, uss_addr, 1)) {
             goto out;
         }
-        ret = target_restore_altstack(uss, sp);
+        ret = target_restore_altstack(uss, get_sp_from_cpustate(env));
         if (ret) {
             goto out;
         }
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index c7c3257f40..32a41c1387 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -11140,8 +11140,7 @@ static abi_long do_syscall1(void *cpu_env, int num, 
abi_long arg1,
         return ret;
     }
     case TARGET_NR_sigaltstack:
-        return do_sigaltstack(arg1, arg2,
-                              get_sp_from_cpustate((CPUArchState *)cpu_env));
+        return do_sigaltstack(arg1, arg2, cpu_env);
 
 #ifdef CONFIG_SENDFILE
 #ifdef TARGET_NR_sendfile
-- 
2.25.1