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Commit 914f8480 authored by David Daney's avatar David Daney Committed by Ralf Baechle
Browse files

MIPS: Octeon: Implement Octeon specific __copy_user_inatomic 



The generic version seems to prefetch past the end of memory.

Signed-off-by: default avatarDavid Daney <ddaney@caviumnetworks.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3929/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 497e5ff0

arch/mips/cavium-octeon/octeon-memcpy.S

+12 −4
Original line number Diff line number Diff line
@@ -163,6 +163,14 @@ 
	.set	noreorder

	.set	noat



/*

 * t7 is used as a flag to note inatomic mode.

 */

LEAF(__copy_user_inatomic)

	b	__copy_user_common

	 li	t7, 1

	END(__copy_user_inatomic)



/*

 * A combined memcpy/__copy_user

 * __copy_user sets len to 0 for success; else to an upper bound of
@@ -174,6 +182,8 @@ LEAF(memcpy) /* a0=dst a1=src a2=len */ 
	move	v0, dst				/* return value */

__memcpy:

FEXPORT(__copy_user)

	li	t7, 0				/* not inatomic */

__copy_user_common:

	/*

	 * Note: dst & src may be unaligned, len may be 0

	 * Temps
@@ -412,7 +422,6 @@ l_exc_copy: 
	 * Assumes src < THREAD_BUADDR($28)

	 */

	LOAD	t0, TI_TASK($28)

	 nop

	LOAD	t0, THREAD_BUADDR(t0)

1:

EXC(	lb	t1, 0(src),	l_exc)
@@ -422,10 +431,9 @@ EXC( lb t1, 0(src), l_exc) 
	 ADD	dst, dst, 1

l_exc:

	LOAD	t0, TI_TASK($28)

	 nop

	LOAD	t0, THREAD_BUADDR(t0)	# t0 is just past last good address

	 nop

	SUB	len, AT, t0		# len number of uncopied bytes

	bnez	t7, 2f		/* Skip the zeroing out part if inatomic */

	/*

	 * Here's where we rely on src and dst being incremented in tandem,

	 *   See (3) above.
@@ -443,7 +451,7 @@ l_exc: 
	ADD	dst, dst, 1

	bnez	src, 1b

	 SUB	src, src, 1

	jr	ra

2:	jr	ra

	 nop