Commit 1d60be3c authored by Al Viro's avatar Al Viro
Browse files

arm: propagate the calling convention changes down to csum_partial_copy_from_user() 



... and get rid of the "clean the destination on error" crap.
Simplifies the fault handlers and the function itself...

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent b7121395

arch/arm/include/asm/checksum.h

+2 −5
Original line number Diff line number Diff line
@@ -38,20 +38,17 @@ __wsum 
csum_partial_copy_nocheck(const void *src, void *dst, int len);



__wsum

csum_partial_copy_from_user(const void __user *src, void *dst, int len, __wsum sum, int *err_ptr);

csum_partial_copy_from_user(const void __user *src, void *dst, int len);



#define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER

#define _HAVE_ARCH_CSUM_AND_COPY

static inline

__wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)

{

	int err = 0;



	if (!access_ok(src, len))

		return 0;



	sum = csum_partial_copy_from_user(src, dst, len, ~0U, &err);

	return err ? 0 : sum;

	return csum_partial_copy_from_user(src, dst, len);

}



/*

arch/arm/lib/csumpartialcopy.S

+0 −1
Original line number Diff line number Diff line
@@ -16,7 +16,6 @@ 


		.macro	save_regs

		stmfd	sp!, {r1, r4 - r8, lr}

		mov	r3, #0

		.endm



		.macro	load_regs

arch/arm/lib/csumpartialcopygeneric.S

+1 −0
Original line number Diff line number Diff line
@@ -86,6 +86,7 @@ sum .req r3 


FN_ENTRY

		save_regs

		mov	sum, #-1



		cmp	len, #8			@ Ensure that we have at least

		blo	.Lless8			@ 8 bytes to copy.

arch/arm/lib/csumpartialcopyuser.S

+6 −20
Original line number Diff line number Diff line
@@ -62,9 +62,9 @@ 


/*

 * unsigned int

 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr)

 *  r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr

 *  Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT

 * csum_partial_copy_from_user(const char *src, char *dst, int len)

 *  r0 = src, r1 = dst, r2 = len

 *  Returns : r0 = checksum or 0

 */



#define FN_ENTRY	ENTRY(csum_partial_copy_from_user)
@@ -73,25 +73,11 @@ 
#include "csumpartialcopygeneric.S"



/*

 * FIXME: minor buglet here

 * We don't return the checksum for the data present in the buffer.  To do

 * so properly, we would have to add in whatever registers were loaded before

 * the fault, which, with the current asm above is not predictable.

 * We report fault by returning 0 csum - impossible in normal case, since

 * we start with 0xffffffff for initial sum.

 */

		.pushsection .text.fixup,"ax"

		.align	4

9001:		mov	r4, #-EFAULT

#ifdef CONFIG_CPU_SW_DOMAIN_PAN

		ldr	r5, [sp, #9*4]		@ *err_ptr

#else

		ldr	r5, [sp, #8*4]		@ *err_ptr

#endif

		str	r4, [r5]

		ldmia	sp, {r1, r2}		@ retrieve dst, len

		add	r2, r2, r1

		mov	r0, #0			@ zero the buffer

9002:		teq	r2, r1

		strbne	r0, [r1], #1

		bne	9002b

9001:		mov	r0, #0

		load_regs

		.popsection