sparc64: Prepare to move to more saner user copy exception handling.

The fixup helper function mechanism for handling user copy fault
handling is not %100 accurrate, and can never be made so.

We are going to transition the code to return the running return
return length, which is always kept track in one or more registers
of each of these routines.

In order to convert them one by one, we have to allow the existing
behavior to continue functioning.

Therefore make all the copy code that wants the fixup helper to be
used return negative one.

After all of the user copy routines have been converted, this logic
and the fixup helpers themselves can be removed completely.

Signed-off-by: David S. Miller <davem@davemloft.net>

15 files changed, 47 insertions, 39 deletions

diff --git a/arch/sparc/include/asm/uaccess_64.h b/arch/sparc/include/asm/uaccess_64.h
index f8518df34b63..0244012435c8 100644
--- a/arch/sparc/include/asm/uaccess_64.h
+++ b/arch/sparc/include/asm/uaccess_64.h
@@ -198,8 +198,11 @@ copy_from_user(void *to, const void __user *from, unsigned long size)
         check_object_size(to, size, false);
 
         ret = ___copy_from_user(to, from, size);
-        if (unlikely(ret))
-                ret = copy_from_user_fixup(to, from, size);
+        if (unlikely(ret)) {
+                if ((long)ret < 0)
+                        ret = copy_from_user_fixup(to, from, size);
+                return ret;
+        }
 
         return ret;
 }
@@ -218,8 +221,11 @@ copy_to_user(void __user *to, const void *from, unsigned long size)
         check_object_size(from, size, true);
 
         ret = ___copy_to_user(to, from, size);
-        if (unlikely(ret))
-                ret = copy_to_user_fixup(to, from, size);
+        if (unlikely(ret)) {
+                if ((long)ret < 0)
+                        ret = copy_to_user_fixup(to, from, size);
+                return ret;
+        }
         return ret;
 }
 #define __copy_to_user copy_to_user
@@ -234,8 +240,11 @@ copy_in_user(void __user *to, void __user *from, unsigned long size)
 {
         unsigned long ret = ___copy_in_user(to, from, size);
 
-        if (unlikely(ret))
-                ret = copy_in_user_fixup(to, from, size);
+        if (unlikely(ret)) {
+                if ((long)ret < 0)
+                        ret = copy_in_user_fixup(to, from, size);
+                return ret;
+        }
         return ret;
 }
 #define __copy_in_user copy_in_user
diff --git a/arch/sparc/kernel/head_64.S b/arch/sparc/kernel/head_64.S
index 603d73654295..5f17de6b5fc3 100644
--- a/arch/sparc/kernel/head_64.S
+++ b/arch/sparc/kernel/head_64.S
@@ -926,41 +926,40 @@ tlb_type:	.word	0	/* Must NOT end up in BSS */
 EXPORT_SYMBOL(tlb_type)
         .section        ".fixup",#alloc,#execinstr
 
-        .globl  __retl_efault, __ret_one, __retl_one
 ENTRY(__retl_efault)
         retl
          mov    -EFAULT, %o0
 ENDPROC(__retl_efault)
 
-ENTRY(__retl_one)
+ENTRY(__retl_mone)
         retl
-         mov    1, %o0
-ENDPROC(__retl_one)
+         mov    -1, %o0
+ENDPROC(__retl_mone)
 
-ENTRY(__retl_one_fp)
+ENTRY(__retl_mone_fp)
         VISExitHalf
         retl
          mov    1, %o0
-ENDPROC(__retl_one_fp)
+ENDPROC(__retl_mone_fp)
 
-ENTRY(__ret_one_asi)
+ENTRY(__ret_mone_asi)
         wr      %g0, ASI_AIUS, %asi
         ret
          restore %g0, 1, %o0
-ENDPROC(__ret_one_asi)
+ENDPROC(__ret_mone_asi)
 
-ENTRY(__retl_one_asi)
+ENTRY(__retl_mone_asi)
         wr      %g0, ASI_AIUS, %asi
         retl
          mov    1, %o0
-ENDPROC(__retl_one_asi)
+ENDPROC(__retl_mone_asi)
 
-ENTRY(__retl_one_asi_fp)
+ENTRY(__retl_mone_asi_fp)
         wr      %g0, ASI_AIUS, %asi
         VISExitHalf
         retl
          mov    1, %o0
-ENDPROC(__retl_one_asi_fp)
+ENDPROC(__retl_mone_asi_fp)
 
 ENTRY(__retl_o1)
         retl
diff --git a/arch/sparc/lib/GENcopy_from_user.S b/arch/sparc/lib/GENcopy_from_user.S
index b7d0bd6b1406..5bce68202246 100644
--- a/arch/sparc/lib/GENcopy_from_user.S
+++ b/arch/sparc/lib/GENcopy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/GENcopy_to_user.S b/arch/sparc/lib/GENcopy_to_user.S
index 780550e1afc7..f663ce3ee8d9 100644
--- a/arch/sparc/lib/GENcopy_to_user.S
+++ b/arch/sparc/lib/GENcopy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NG2copy_from_user.S b/arch/sparc/lib/NG2copy_from_user.S
index d5242b8c4f94..4d47fa5519d4 100644
--- a/arch/sparc/lib/NG2copy_from_user.S
+++ b/arch/sparc/lib/NG2copy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi;\
+        .word 98b, __retl_mone_asi;\
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi_fp;\
+        .word 98b, __retl_mone_asi_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NG2copy_to_user.S b/arch/sparc/lib/NG2copy_to_user.S
index 4e962d993b10..2078d752709a 100644
--- a/arch/sparc/lib/NG2copy_to_user.S
+++ b/arch/sparc/lib/NG2copy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi;\
+        .word 98b, __retl_mone_asi;\
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi_fp;\
+        .word 98b, __retl_mone_asi_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NG4copy_from_user.S b/arch/sparc/lib/NG4copy_from_user.S
index 2e8ee7ad07a9..f9746e7cf25e 100644
--- a/arch/sparc/lib/NG4copy_from_user.S
+++ b/arch/sparc/lib/NG4copy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi;\
+        .word 98b, __retl_mone_asi;\
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi_fp;\
+        .word 98b, __retl_mone_asi_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NG4copy_to_user.S b/arch/sparc/lib/NG4copy_to_user.S
index be0bf4590df8..5fa44349adde 100644
--- a/arch/sparc/lib/NG4copy_to_user.S
+++ b/arch/sparc/lib/NG4copy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi;\
+        .word 98b, __retl_mone_asi;\
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_asi_fp;\
+        .word 98b, __retl_mone_asi_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NGcopy_from_user.S b/arch/sparc/lib/NGcopy_from_user.S
index 5d1e4d1ac21e..e61694c444af 100644
--- a/arch/sparc/lib/NGcopy_from_user.S
+++ b/arch/sparc/lib/NGcopy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __ret_one_asi;\
+        .word 98b, __ret_mone_asi;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NGcopy_to_user.S b/arch/sparc/lib/NGcopy_to_user.S
index ff630dcb273c..2d6b33d3998f 100644
--- a/arch/sparc/lib/NGcopy_to_user.S
+++ b/arch/sparc/lib/NGcopy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __ret_one_asi;\
+        .word 98b, __ret_mone_asi;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/U1copy_from_user.S b/arch/sparc/lib/U1copy_from_user.S
index ecc5692fa2b4..1ad59fbac7a7 100644
--- a/arch/sparc/lib/U1copy_from_user.S
+++ b/arch/sparc/lib/U1copy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_fp;\
+        .word 98b, __retl_mone_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/U1copy_to_user.S b/arch/sparc/lib/U1copy_to_user.S
index 9eea392e44d4..adcc3a510185 100644
--- a/arch/sparc/lib/U1copy_to_user.S
+++ b/arch/sparc/lib/U1copy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_fp;\
+        .word 98b, __retl_mone_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/U3copy_from_user.S b/arch/sparc/lib/U3copy_from_user.S
index 88ad73d86fe4..1046e2b083fe 100644
--- a/arch/sparc/lib/U3copy_from_user.S
+++ b/arch/sparc/lib/U3copy_from_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_fp;\
+        .word 98b, __retl_mone_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/U3copy_to_user.S b/arch/sparc/lib/U3copy_to_user.S
index 845139d75537..032b0c5419b0 100644
--- a/arch/sparc/lib/U3copy_to_user.S
+++ b/arch/sparc/lib/U3copy_to_user.S
@@ -7,7 +7,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;
 
@@ -15,7 +15,7 @@
 98:     x;                      \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one_fp;\
+        .word 98b, __retl_mone_fp;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/copy_in_user.S b/arch/sparc/lib/copy_in_user.S
index 482de093bdae..86e6663dd4e0 100644
--- a/arch/sparc/lib/copy_in_user.S
+++ b/arch/sparc/lib/copy_in_user.S
@@ -13,7 +13,7 @@
 98:     x,y;                    \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_one;  \
+        .word 98b, __retl_mone; \
         .text;                  \
         .align 4;