Merge branch 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull copy_and_csum cleanups from Al Viro:
 "Saner calling conventions for csum_and_copy_..._user() and friends"

[ Removing 800+ lines of code and cleaning stuff up is good  - Linus ]

* 'work.csum_and_copy' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ppc: propagate the calling conventions change down to csum_partial_copy_generic()
  amd64: switch csum_partial_copy_generic() to new calling conventions
  sparc64: propagate the calling convention changes down to __csum_partial_copy_...()
  xtensa: propagate the calling conventions change down into csum_partial_copy_generic()
  mips: propagate the calling convention change down into __csum_partial_copy_..._user()
  mips: __csum_partial_copy_kernel() has no users left
  mips: csum_and_copy_{to,from}_user() are never called under KERNEL_DS
  sparc32: propagate the calling conventions change down to __csum_partial_copy_sparc_generic()
  i386: propagate the calling conventions change down to csum_partial_copy_generic()
  sh: propage the calling conventions change down to csum_partial_copy_generic()
  m68k: get rid of zeroing destination on error in csum_and_copy_from_user()
  arm: propagate the calling convention changes down to csum_partial_copy_from_user()
  alpha: propagate the calling convention changes down to csum_partial_copy.c helpers
  saner calling conventions for csum_and_copy_..._user()
  csum_and_copy_..._user(): pass 0xffffffff instead of 0 as initial sum
  csum_partial_copy_nocheck(): drop the last argument
  unify generic instances of csum_partial_copy_nocheck()
  icmp_push_reply(): reorder adding the checksum up
  skb_copy_and_csum_bits(): don't bother with the last argument

3 files changed, 52 insertions, 133 deletions

diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
index ecd150dc3ed9..ec5cd2dede35 100644
--- a/arch/powerpc/lib/checksum_32.S
+++ b/arch/powerpc/lib/checksum_32.S
@@ -78,12 +78,10 @@ EXPORT_SYMBOL(__csum_partial)
 
 /*
  * Computes the checksum of a memory block at src, length len,
- * and adds in "sum" (32-bit), while copying the block to dst.
- * If an access exception occurs on src or dst, it stores -EFAULT
- * to *src_err or *dst_err respectively, and (for an error on
- * src) zeroes the rest of dst.
+ * and adds in 0xffffffff, while copying the block to dst.
+ * If an access exception occurs it returns zero.
  *
- * csum_partial_copy_generic(src, dst, len, sum, src_err, dst_err)
+ * csum_partial_copy_generic(src, dst, len)
  */
 #define CSUM_COPY_16_BYTES_WITHEX(n)	\
 8 ## n ## 0:			\
@@ -108,14 +106,14 @@ EXPORT_SYMBOL(__csum_partial)
 	adde	r12,r12,r10
 
 #define CSUM_COPY_16_BYTES_EXCODE(n)		\
-	EX_TABLE(8 ## n ## 0b, src_error);	\
-	EX_TABLE(8 ## n ## 1b, src_error);	\
-	EX_TABLE(8 ## n ## 2b, src_error);	\
-	EX_TABLE(8 ## n ## 3b, src_error);	\
-	EX_TABLE(8 ## n ## 4b, dst_error);	\
-	EX_TABLE(8 ## n ## 5b, dst_error);	\
-	EX_TABLE(8 ## n ## 6b, dst_error);	\
-	EX_TABLE(8 ## n ## 7b, dst_error);
+	EX_TABLE(8 ## n ## 0b, fault);	\
+	EX_TABLE(8 ## n ## 1b, fault);	\
+	EX_TABLE(8 ## n ## 2b, fault);	\
+	EX_TABLE(8 ## n ## 3b, fault);	\
+	EX_TABLE(8 ## n ## 4b, fault);	\
+	EX_TABLE(8 ## n ## 5b, fault);	\
+	EX_TABLE(8 ## n ## 6b, fault);	\
+	EX_TABLE(8 ## n ## 7b, fault);
 
 	.text
 	.stabs	"arch/powerpc/lib/",N_SO,0,0,0f
@@ -127,11 +125,8 @@ LG_CACHELINE_BYTES = L1_CACHE_SHIFT
 CACHELINE_MASK = (L1_CACHE_BYTES-1)
 
 _GLOBAL(csum_partial_copy_generic)
-	stwu	r1,-16(r1)
-	stw	r7,12(r1)
-	stw	r8,8(r1)
-
-	addic	r12,r6,0
+	li	r12,-1
+	addic	r0,r0,0			/* clear carry */
 	addi	r6,r4,-4
 	neg	r0,r4
 	addi	r4,r3,-4
@@ -246,34 +241,19 @@ _GLOBAL(csum_partial_copy_generic)
 	rlwinm	r3,r3,8,0,31	/* odd destination address: rotate one byte */
 	blr
 
-/* read fault */
-src_error:
-	lwz	r7,12(r1)
-	addi	r1,r1,16
-	cmpwi	cr0,r7,0
-	beqlr
-	li	r0,-EFAULT
-	stw	r0,0(r7)
-	blr
-/* write fault */
-dst_error:
-	lwz	r8,8(r1)
-	addi	r1,r1,16
-	cmpwi	cr0,r8,0
-	beqlr
-	li	r0,-EFAULT
-	stw	r0,0(r8)
+fault:
+	li	r3,0
 	blr
 
-	EX_TABLE(70b, src_error);
-	EX_TABLE(71b, dst_error);
-	EX_TABLE(72b, src_error);
-	EX_TABLE(73b, dst_error);
-	EX_TABLE(54b, dst_error);
+	EX_TABLE(70b, fault);
+	EX_TABLE(71b, fault);
+	EX_TABLE(72b, fault);
+	EX_TABLE(73b, fault);
+	EX_TABLE(54b, fault);
 
 /*
  * this stuff handles faults in the cacheline loop and branches to either
- * src_error (if in read part) or dst_error (if in write part)
+ * fault (if in read part) or fault (if in write part)
  */
 	CSUM_COPY_16_BYTES_EXCODE(0)
 #if L1_CACHE_BYTES >= 32
@@ -290,12 +270,12 @@ dst_error:
 #endif
 #endif
 
-	EX_TABLE(30b, src_error);
-	EX_TABLE(31b, dst_error);
-	EX_TABLE(40b, src_error);
-	EX_TABLE(41b, dst_error);
-	EX_TABLE(50b, src_error);
-	EX_TABLE(51b, dst_error);
+	EX_TABLE(30b, fault);
+	EX_TABLE(31b, fault);
+	EX_TABLE(40b, fault);
+	EX_TABLE(41b, fault);
+	EX_TABLE(50b, fault);
+	EX_TABLE(51b, fault);
 
 EXPORT_SYMBOL(csum_partial_copy_generic)
 
diff --git a/arch/powerpc/lib/checksum_64.S b/arch/powerpc/lib/checksum_64.S
index 514978f908d4..98ff51bd2f7d 100644
--- a/arch/powerpc/lib/checksum_64.S
+++ b/arch/powerpc/lib/checksum_64.S
@@ -182,34 +182,33 @@ EXPORT_SYMBOL(__csum_partial)
 
 	.macro srcnr
 100:
-	EX_TABLE(100b,.Lsrc_error_nr)
+	EX_TABLE(100b,.Lerror_nr)
 	.endm
 
 	.macro source
 150:
-	EX_TABLE(150b,.Lsrc_error)
+	EX_TABLE(150b,.Lerror)
 	.endm
 
 	.macro dstnr
 200:
-	EX_TABLE(200b,.Ldest_error_nr)
+	EX_TABLE(200b,.Lerror_nr)
 	.endm
 
 	.macro dest
 250:
-	EX_TABLE(250b,.Ldest_error)
+	EX_TABLE(250b,.Lerror)
 	.endm
 
 /*
  * Computes the checksum of a memory block at src, length len,
- * and adds in "sum" (32-bit), while copying the block to dst.
- * If an access exception occurs on src or dst, it stores -EFAULT
- * to *src_err or *dst_err respectively. The caller must take any action
- * required in this case (zeroing memory, recalculating partial checksum etc).
+ * and adds in 0xffffffff (32-bit), while copying the block to dst.
+ * If an access exception occurs, it returns 0.
  *
- * csum_partial_copy_generic(r3=src, r4=dst, r5=len, r6=sum, r7=src_err, r8=dst_err)
+ * csum_partial_copy_generic(r3=src, r4=dst, r5=len)
  */
 _GLOBAL(csum_partial_copy_generic)
+	li	r6,-1
 	addic	r0,r6,0			/* clear carry */
 
 	srdi.	r6,r5,3			/* less than 8 bytes? */
@@ -401,29 +400,15 @@ dstnr;	stb	r6,0(r4)
 	srdi	r3,r3,32
 	blr
 
-.Lsrc_error:
+.Lerror:
 	ld	r14,STK_REG(R14)(r1)
 	ld	r15,STK_REG(R15)(r1)
 	ld	r16,STK_REG(R16)(r1)
 	addi	r1,r1,STACKFRAMESIZE
-.Lsrc_error_nr:
-	cmpdi	0,r7,0
-	beqlr
-	li	r6,-EFAULT
-	stw	r6,0(r7)
+.Lerror_nr:
+	li	r3,0
 	blr
 
-.Ldest_error:
-	ld	r14,STK_REG(R14)(r1)
-	ld	r15,STK_REG(R15)(r1)
-	ld	r16,STK_REG(R16)(r1)
-	addi	r1,r1,STACKFRAMESIZE
-.Ldest_error_nr:
-	cmpdi	0,r8,0
-	beqlr
-	li	r6,-EFAULT
-	stw	r6,0(r8)
-	blr
 EXPORT_SYMBOL(csum_partial_copy_generic)
 
 /*
diff --git a/arch/powerpc/lib/checksum_wrappers.c b/arch/powerpc/lib/checksum_wrappers.c
index fabe4db28726..b895166afc82 100644
--- a/arch/powerpc/lib/checksum_wrappers.c
+++ b/arch/powerpc/lib/checksum_wrappers.c
@@ -12,83 +12,37 @@
 #include <linux/uaccess.h>
 
 __wsum csum_and_copy_from_user(const void __user *src, void *dst,
-			       int len, __wsum sum, int *err_ptr)
+			       int len)
 {
-	unsigned int csum;
+	__wsum csum;
 
 	might_sleep();
-	allow_read_from_user(src, len);
-
-	*err_ptr = 0;
-
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
 
-	if (unlikely((len < 0) || !access_ok(src, len))) {
-		*err_ptr = -EFAULT;
-		csum = (__force unsigned int)sum;
-		goto out;
-	}
+	if (unlikely(!access_ok(src, len)))
+		return 0;
 
-	csum = csum_partial_copy_generic((void __force *)src, dst,
-					 len, sum, err_ptr, NULL);
-
-	if (unlikely(*err_ptr)) {
-		int missing = __copy_from_user(dst, src, len);
-
-		if (missing) {
-			memset(dst + len - missing, 0, missing);
-			*err_ptr = -EFAULT;
-		} else {
-			*err_ptr = 0;
-		}
+	allow_read_from_user(src, len);
 
-		csum = csum_partial(dst, len, sum);
-	}
+	csum = csum_partial_copy_generic((void __force *)src, dst, len);
 
-out:
 	prevent_read_from_user(src, len);
-	return (__force __wsum)csum;
+	return csum;
 }
 EXPORT_SYMBOL(csum_and_copy_from_user);
 
-__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
-			     __wsum sum, int *err_ptr)
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
 {
-	unsigned int csum;
+	__wsum csum;
 
 	might_sleep();
-	allow_write_to_user(dst, len);
-
-	*err_ptr = 0;
-
-	if (!len) {
-		csum = 0;
-		goto out;
-	}
+	if (unlikely(!access_ok(dst, len)))
+		return 0;
 
-	if (unlikely((len < 0) || !access_ok(dst, len))) {
-		*err_ptr = -EFAULT;
-		csum = -1; /* invalid checksum */
-		goto out;
-	}
-
-	csum = csum_partial_copy_generic(src, (void __force *)dst,
-					 len, sum, NULL, err_ptr);
-
-	if (unlikely(*err_ptr)) {
-		csum = csum_partial(src, len, sum);
+	allow_write_to_user(dst, len);
 
-		if (copy_to_user(dst, src, len)) {
-			*err_ptr = -EFAULT;
-			csum = -1; /* invalid checksum */
-		}
-	}
+	csum = csum_partial_copy_generic(src, (void __force *)dst, len);
 
-out:
 	prevent_write_to_user(dst, len);
-	return (__force __wsum)csum;
+	return csum;
 }
 EXPORT_SYMBOL(csum_and_copy_to_user);