Merge branch 'parisc-4.11-3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...

[karo-tx-linux.git] / arch / parisc / include / asm / uaccess.h

diff --git a/arch/parisc/include/asm/uaccess.h b/arch/parisc/include/asm/uaccess.h
index a0b461336b6a28ce4cdcd474fe74d626cec3c808..cbb0aaca8d391d3961a283a9d39c7a6d4b650f38 100644 (file)
--- a/arch/parisc/include/asm/uaccess.h
+++ b/arch/parisc/include/asm/uaccess.h
@@ -27,7 +27,8 @@
  * that put_user is the same as __put_user, etc.
  */
 
-#define access_ok(type, uaddr, size) (1)
+#define access_ok(type, uaddr, size)   \
+       ( (uaddr) == (uaddr) )
 
 #define put_user __put_user
 #define get_user __get_user
@@ -58,6 +59,15 @@ struct exception_table_entry {
        ".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
        ".previous\n"
 
+/*
+ * ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry
+ * (with lowest bit set) for which the fault handler in fixup_exception() will
+ * load -EFAULT into %r8 for a read or write fault, and zeroes the target
+ * register in case of a read fault in get_user().
+ */
+#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\
+       ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1)
+
 /*
  * The page fault handler stores, in a per-cpu area, the following information
  * if a fixup routine is available.
@@ -85,7 +95,7 @@ struct exception_data {
 #define __get_user(x, ptr)                               \
 ({                                                       \
        register long __gu_err __asm__ ("r8") = 0;       \
-       register long __gu_val __asm__ ("r9") = 0;       \
+       register long __gu_val;                          \
                                                         \
        load_sr2();                                      \
        switch (sizeof(*(ptr))) {                        \
@@ -101,22 +111,23 @@ struct exception_data {
 })
 
 #define __get_user_asm(ldx, ptr)                        \
-       __asm__("\n1:\t" ldx "\t0(%%sr2,%2),%0\n\t"     \
-               ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
+       __asm__("1: " ldx " 0(%%sr2,%2),%0\n"           \
+               "9:\n"                                  \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
                : "=r"(__gu_val), "=r"(__gu_err)        \
-               : "r"(ptr), "1"(__gu_err)               \
-               : "r1");
+               : "r"(ptr), "1"(__gu_err));
 
 #if !defined(CONFIG_64BIT)
 
 #define __get_user_asm64(ptr)                          \
-       __asm__("\n1:\tldw 0(%%sr2,%2),%0"              \
-               "\n2:\tldw 4(%%sr2,%2),%R0\n\t"         \
-               ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_2)\
-               ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_get_user_skip_1)\
+       __asm__("   copy %%r0,%R0\n"                    \
+               "1: ldw 0(%%sr2,%2),%0\n"               \
+               "2: ldw 4(%%sr2,%2),%R0\n"              \
+               "9:\n"                                  \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
                : "=r"(__gu_val), "=r"(__gu_err)        \
-               : "r"(ptr), "1"(__gu_err)               \
-               : "r1");
+               : "r"(ptr), "1"(__gu_err));
 
 #endif /* !defined(CONFIG_64BIT) */
 
@@ -142,32 +153,31 @@ struct exception_data {
  * The "__put_user/kernel_asm()" macros tell gcc they read from memory
  * instead of writing. This is because they do not write to any memory
  * gcc knows about, so there are no aliasing issues. These macros must
- * also be aware that "fixup_put_user_skip_[12]" are executed in the
- * context of the fault, and any registers used there must be listed
- * as clobbers. In this case only "r1" is used by the current routines.
- * r8/r9 are already listed as err/val.
+ * also be aware that fixups are executed in the context of the fault,
+ * and any registers used there must be listed as clobbers.
+ * r8 is already listed as err.
  */
 
 #define __put_user_asm(stx, x, ptr)                         \
        __asm__ __volatile__ (                              \
-               "\n1:\t" stx "\t%2,0(%%sr2,%1)\n\t"         \
-               ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
+               "1: " stx " %2,0(%%sr2,%1)\n"               \
+               "9:\n"                                      \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)     \
                : "=r"(__pu_err)                            \
-               : "r"(ptr), "r"(x), "0"(__pu_err)           \
-               : "r1")
+               : "r"(ptr), "r"(x), "0"(__pu_err))
 
 
 #if !defined(CONFIG_64BIT)
 
 #define __put_user_asm64(__val, ptr) do {                  \
        __asm__ __volatile__ (                              \
-               "\n1:\tstw %2,0(%%sr2,%1)"                  \
-               "\n2:\tstw %R2,4(%%sr2,%1)\n\t"             \
-               ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
-               ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
+               "1: stw %2,0(%%sr2,%1)\n"                   \
+               "2: stw %R2,4(%%sr2,%1)\n"                  \
+               "9:\n"                                      \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b)     \
+               ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b)     \
                : "=r"(__pu_err)                            \
-               : "r"(ptr), "r"(__val), "0"(__pu_err) \
-               : "r1");                                    \
+               : "r"(ptr), "r"(__val), "0"(__pu_err));     \
 } while (0)
 
 #endif /* !defined(CONFIG_64BIT) */