4 files changed, 47 insertions, 45 deletions

diff --git a/linux-user/main.c b/linux-user/main.c
index 15bacb9a30..0181bc2112 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -57,7 +57,12 @@ int have_guest_base;
  * This way we will never overlap with our own libraries or binaries or stack
  * or anything else that QEMU maps.
  */
+# ifdef TARGET_MIPS
+/* MIPS only supports 31 bits of virtual address space for user space */
+unsigned long reserved_va = 0x77000000;
+# else
 unsigned long reserved_va = 0xf7000000;
+# endif
 #else
 unsigned long reserved_va;
 #endif
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index 8a3538c631..31a220af81 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -287,36 +287,39 @@ static inline int access_ok(int type, abi_ulong addr, abi_ulong size)
                             (type == VERIFY_READ) ? PAGE_READ : (PAGE_READ | PAGE_WRITE)) == 0;
 }
 
-/* NOTE __get_user and __put_user use host pointers and don't check access. */
-/* These are usually used to access struct data members once the
- * struct has been locked - usually with lock_user_struct().
- */
-#define __put_user(x, hptr)\
-({ __typeof(*hptr) pu_ = (x);\
-    switch(sizeof(*hptr)) {\
-    case 1: break;\
-    case 2: pu_ = tswap16(pu_); break; \
-    case 4: pu_ = tswap32(pu_); break; \
-    case 8: pu_ = tswap64(pu_); break; \
-    default: abort();\
-    }\
-    memcpy(hptr, &pu_, sizeof(pu_)); \
-    0;\
-})
-
-#define __get_user(x, hptr) \
-({ __typeof(*hptr) gu_; \
-    memcpy(&gu_, hptr, sizeof(gu_)); \
-    switch(sizeof(*hptr)) {\
-    case 1: break; \
-    case 2: gu_ = tswap16(gu_); break; \
-    case 4: gu_ = tswap32(gu_); break; \
-    case 8: gu_ = tswap64(gu_); break; \
-    default: abort();\
-    }\
-    (x) = gu_; \
-    0;\
-})
+/* NOTE __get_user and __put_user use host pointers and don't check access.
+   These are usually used to access struct data members once the struct has
+   been locked - usually with lock_user_struct.  */
+
+/* Tricky points:
+   - Use __builtin_choose_expr to avoid type promotion from ?:,
+   - Invalid sizes result in a compile time error stemming from
+     the fact that abort has no parameters.
+   - It's easier to use the endian-specific unaligned load/store
+     functions than host-endian unaligned load/store plus tswapN.  */
+
+#define __put_user_e(x, hptr, e)                                        \
+  (__builtin_choose_expr(sizeof(*(hptr)) == 1, stb_p,                   \
+   __builtin_choose_expr(sizeof(*(hptr)) == 2, stw_##e##_p,             \
+   __builtin_choose_expr(sizeof(*(hptr)) == 4, stl_##e##_p,             \
+   __builtin_choose_expr(sizeof(*(hptr)) == 8, stq_##e##_p, abort))))   \
+     ((hptr), (x)), 0)
+
+#define __get_user_e(x, hptr, e)                                        \
+  ((x) =                                                                \
+   __builtin_choose_expr(sizeof(*(hptr)) == 1, ldub_p,                  \
+   __builtin_choose_expr(sizeof(*(hptr)) == 2, lduw_##e##_p,            \
+   __builtin_choose_expr(sizeof(*(hptr)) == 4, ldl_##e##_p,             \
+   __builtin_choose_expr(sizeof(*(hptr)) == 8, ldq_##e##_p, abort))))   \
+     (hptr), 0)
+
+#ifdef TARGET_WORDS_BIGENDIAN
+# define __put_user(x, hptr)  __put_user_e(x, hptr, be)
+# define __get_user(x, hptr)  __get_user_e(x, hptr, be)
+#else
+# define __put_user(x, hptr)  __put_user_e(x, hptr, le)
+# define __get_user(x, hptr)  __get_user_e(x, hptr, le)
+#endif
 
 /* put_user()/get_user() take a guest address and check access */
 /* These are usually used to access an atomic data type, such as an int,
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 95e2ffa007..407619ac4e 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -607,28 +607,22 @@ int do_sigaction(int sig, const struct target_sigaction *act,
             sig, act, oact);
 #endif
     if (oact) {
-        oact->_sa_handler = tswapal(k->_sa_handler);
-#if defined(TARGET_MIPS) || defined (TARGET_ALPHA)
-        oact->sa_flags = bswap32(k->sa_flags);
-#else
-        oact->sa_flags = tswapal(k->sa_flags);
-#endif
+        __put_user(k->_sa_handler, &oact->_sa_handler);
+        __put_user(k->sa_flags, &oact->sa_flags);
 #if !defined(TARGET_MIPS)
-        oact->sa_restorer = tswapal(k->sa_restorer);
+        __put_user(k->sa_restorer, &oact->sa_restorer);
 #endif
+        /* Not swapped.  */
         oact->sa_mask = k->sa_mask;
     }
     if (act) {
         /* FIXME: This is not threadsafe.  */
-        k->_sa_handler = tswapal(act->_sa_handler);
-#if defined(TARGET_MIPS) || defined (TARGET_ALPHA)
-        k->sa_flags = bswap32(act->sa_flags);
-#else
-        k->sa_flags = tswapal(act->sa_flags);
-#endif
+        __get_user(k->_sa_handler, &act->_sa_handler);
+        __get_user(k->sa_flags, &act->sa_flags);
 #if !defined(TARGET_MIPS)
-        k->sa_restorer = tswapal(act->sa_restorer);
+        __get_user(k->sa_restorer, &act->sa_restorer);
 #endif
+        /* To be swapped in target_to_host_sigset.  */
         k->sa_mask = act->sa_mask;
 
         /* we update the host linux signal state */
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index d4589e7906..f8f553915d 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -544,7 +544,7 @@ int do_sigaction(int sig, const struct target_sigaction *act,
 struct target_old_sigaction {
     abi_ulong _sa_handler;
     abi_ulong sa_mask;
-    abi_ulong sa_flags;
+    int32_t sa_flags;
 };
 
 struct target_rt_sigaction {