linux-user: Rewrite __get_user/__put_user with __builtin_choose_expr

[qemu.git] / linux-user / qemu.h

diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index dd74cc05103d2db93eb33e8ea1fafaa53e511772..31a220af81694cc1fc1f2f9c603efc8443f92c48 100644 (file)
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -11,14 +11,14 @@
 #include <stdlib.h>
 #endif /* DEBUG_REMAP */
 
-#include "qemu-types.h"
+#include "exec/user/abitypes.h"
 
-#include "thunk.h"
+#include "exec/user/thunk.h"
 #include "syscall_defs.h"
 #include "syscall.h"
 #include "target_signal.h"
-#include "gdbstub.h"
-#include "qemu-queue.h"
+#include "exec/gdbstub.h"
+#include "qemu/queue.h"
 
 #if defined(CONFIG_USE_NPTL)
 #define THREAD __thread
@@ -51,6 +51,7 @@ struct image_info {
         abi_ulong       auxv_len;
         abi_ulong       arg_start;
         abi_ulong       arg_end;
+        uint32_t        elf_flags;
        int             personality;
 #ifdef CONFIG_USE_FDPIC
         abi_ulong       loadmap_addr;
@@ -203,13 +204,23 @@ int get_osversion(void);
 void fork_start(void);
 void fork_end(int child);
 
-/* Return true if the proposed guest_base is suitable for the guest.
- * The guest code may leave a page mapped and populate it if the
- * address is suitable.
+/* Creates the initial guest address space in the host memory space using
+ * the given host start address hint and size.  The guest_start parameter
+ * specifies the start address of the guest space.  guest_base will be the
+ * difference between the host start address computed by this function and
+ * guest_start.  If fixed is specified, then the mapped address space must
+ * start at host_start.  The real start address of the mapped memory space is
+ * returned or -1 if there was an error.
  */
-bool guest_validate_base(unsigned long guest_base);
+unsigned long init_guest_space(unsigned long host_start,
+                               unsigned long host_size,
+                               unsigned long guest_start,
+                               bool fixed);
 
-#include "qemu-log.h"
+#include "qemu/log.h"
+
+/* syscall.c */
+int host_to_target_waitstatus(int status);
 
 /* strace.c */
 void print_syscall(int num,
@@ -276,53 +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)\
-({\
-    switch(sizeof(*hptr)) {\
-    case 1:\
-        *(uint8_t *)(hptr) = (uint8_t)(typeof(*hptr))(x);\
-        break;\
-    case 2:\
-        *(uint16_t *)(hptr) = tswap16((uint16_t)(typeof(*hptr))(x));\
-        break;\
-    case 4:\
-        *(uint32_t *)(hptr) = tswap32((uint32_t)(typeof(*hptr))(x));\
-        break;\
-    case 8:\
-        *(uint64_t *)(hptr) = tswap64((typeof(*hptr))(x));\
-        break;\
-    default:\
-        abort();\
-    }\
-    0;\
-})
-
-#define __get_user(x, hptr) \
-({\
-    switch(sizeof(*hptr)) {\
-    case 1:\
-        x = (typeof(*hptr))*(uint8_t *)(hptr);\
-        break;\
-    case 2:\
-        x = (typeof(*hptr))tswap16(*(uint16_t *)(hptr));\
-        break;\
-    case 4:\
-        x = (typeof(*hptr))tswap32(*(uint32_t *)(hptr));\
-        break;\
-    case 8:\
-        x = (typeof(*hptr))tswap64(*(uint64_t *)(hptr));\
-        break;\
-    default:\
-        /* avoid warning */\
-        x = 0;\
-        abort();\
-    }\
-    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,