From 1a4fded6d32596053d4f0bc8c49028faf4114a17 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 20 Mar 2017 12:03:16 -0400 Subject: [PATCH] mips: get rid of tail-zeroing in primitives Signed-off-by: Al Viro --- arch/mips/cavium-octeon/octeon-memcpy.S | 31 +--------------- arch/mips/include/asm/uaccess.h | 19 +--------- arch/mips/lib/memcpy.S | 49 ------------------------- 3 files changed, 3 insertions(+), 96 deletions(-) diff --git a/arch/mips/cavium-octeon/octeon-memcpy.S b/arch/mips/cavium-octeon/octeon-memcpy.S index cfd97f6448bb..0a7c9834b81c 100644 --- a/arch/mips/cavium-octeon/octeon-memcpy.S +++ b/arch/mips/cavium-octeon/octeon-memcpy.S @@ -139,15 +139,6 @@ .set noreorder .set noat -/* - * t7 is used as a flag to note inatomic mode. - */ -LEAF(__copy_user_inatomic) -EXPORT_SYMBOL(__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 @@ -161,8 +152,6 @@ EXPORT_SYMBOL(memcpy) __memcpy: FEXPORT(__copy_user) EXPORT_SYMBOL(__copy_user) - li t7, 0 /* not inatomic */ -__copy_user_common: /* * Note: dst & src may be unaligned, len may be 0 * Temps @@ -414,25 +403,7 @@ l_exc: LOAD t0, TI_TASK($28) LOAD t0, THREAD_BUADDR(t0) # t0 is just past last good address 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. - * dst += (fault addr - src) to put dst at first byte to clear - */ - ADD dst, t0 # compute start address in a1 - SUB dst, src - /* - * Clear len bytes starting at dst. Can't call __bzero because it - * might modify len. An inefficient loop for these rare times... - */ - beqz len, done - SUB src, len, 1 -1: sb zero, 0(dst) - ADD dst, dst, 1 - bnez src, 1b - SUB src, src, 1 -2: jr ra + jr ra nop diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h index 712dc40625b6..988cd3b64a59 100644 --- a/arch/mips/include/asm/uaccess.h +++ b/arch/mips/include/asm/uaccess.h @@ -841,9 +841,6 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n); #define __invoke_copy_from_kernel(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) -#define __invoke_copy_from_kernel_inatomic(to, from, n) \ - __invoke_copy_from(__copy_user_inatomic, to, from, n) - #define __invoke_copy_to_kernel(to, from, n) \ __invoke_copy_to(__copy_user, to, from, n) @@ -854,9 +851,6 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n); #define __invoke_copy_from_user(to, from, n) \ __invoke_copy_from(__copy_user, to, from, n) -#define __invoke_copy_from_user_inatomic(to, from, n) \ - __invoke_copy_from(__copy_user_inatomic, to, from, n) - #define __invoke_copy_to_user(to, from, n) \ __invoke_copy_to(__copy_user, to, from, n) @@ -867,8 +861,6 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n); /* EVA specific functions */ -extern size_t __copy_user_inatomic_eva(void *__to, const void *__from, - size_t __n); extern size_t __copy_from_user_eva(void *__to, const void *__from, size_t __n); extern size_t __copy_to_user_eva(void *__to, const void *__from, @@ -882,9 +874,6 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n); #define __invoke_copy_from_user(to, from, n) \ __invoke_copy_from(__copy_from_user_eva, to, from, n) -#define __invoke_copy_from_user_inatomic(to, from, n) \ - __invoke_copy_from(__copy_user_inatomic_eva, to, from, n) - #define __invoke_copy_to_user(to, from, n) \ __invoke_copy_to(__copy_to_user_eva, to, from, n) @@ -930,8 +919,6 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n); __cu_len; \ }) -extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n); - #define __copy_to_user_inatomic(to, from, n) \ ({ \ void __user *__cu_to; \ @@ -966,12 +953,10 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n); check_object_size(__cu_to, __cu_len, false); \ \ if (eva_kernel_access()) \ - __cu_len = __invoke_copy_from_kernel_inatomic(__cu_to, \ - __cu_from,\ + __cu_len = __invoke_copy_from_kernel(__cu_to, __cu_from,\ __cu_len);\ else \ - __cu_len = __invoke_copy_from_user_inatomic(__cu_to, \ - __cu_from, \ + __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \ __cu_len); \ __cu_len; \ }) diff --git a/arch/mips/lib/memcpy.S b/arch/mips/lib/memcpy.S index c3031f18c572..3114a2ed1f4e 100644 --- a/arch/mips/lib/memcpy.S +++ b/arch/mips/lib/memcpy.S @@ -562,39 +562,9 @@ LOADK t0, THREAD_BUADDR(t0) # t0 is just past last good address nop SUB len, AT, t0 # len number of uncopied bytes - bnez t6, .Ldone\@ /* Skip the zeroing part if inatomic */ - /* - * Here's where we rely on src and dst being incremented in tandem, - * See (3) above. - * dst += (fault addr - src) to put dst at first byte to clear - */ - ADD dst, t0 # compute start address in a1 - SUB dst, src - /* - * Clear len bytes starting at dst. Can't call __bzero because it - * might modify len. An inefficient loop for these rare times... - */ - .set reorder /* DADDI_WAR */ - SUB src, len, 1 - beqz len, .Ldone\@ - .set noreorder -1: sb zero, 0(dst) - ADD dst, dst, 1 -#ifndef CONFIG_CPU_DADDI_WORKAROUNDS - bnez src, 1b - SUB src, src, 1 -#else - .set push - .set noat - li v1, 1 - bnez src, 1b - SUB src, src, v1 - .set pop -#endif jr ra nop - #define SEXC(n) \ .set reorder; /* DADDI_WAR */ \ .Ls_exc_p ## n ## u\@: \ @@ -672,15 +642,6 @@ LEAF(__rmemcpy) /* a0=dst a1=src a2=len */ move a2, zero END(__rmemcpy) -/* - * t6 is used as a flag to note inatomic mode. - */ -LEAF(__copy_user_inatomic) -EXPORT_SYMBOL(__copy_user_inatomic) - b __copy_user_common - li t6, 1 - END(__copy_user_inatomic) - /* * A combined memcpy/__copy_user * __copy_user sets len to 0 for success; else to an upper bound of @@ -694,8 +655,6 @@ EXPORT_SYMBOL(memcpy) .L__memcpy: FEXPORT(__copy_user) EXPORT_SYMBOL(__copy_user) - li t6, 0 /* not inatomic */ -__copy_user_common: /* Legacy Mode, user <-> user */ __BUILD_COPY_USER LEGACY_MODE USEROP USEROP @@ -708,20 +667,12 @@ __copy_user_common: * space */ -LEAF(__copy_user_inatomic_eva) -EXPORT_SYMBOL(__copy_user_inatomic_eva) - b __copy_from_user_common - li t6, 1 - END(__copy_user_inatomic_eva) - /* * __copy_from_user (EVA) */ LEAF(__copy_from_user_eva) EXPORT_SYMBOL(__copy_from_user_eva) - li t6, 0 /* not inatomic */ -__copy_from_user_common: __BUILD_COPY_USER EVA_MODE USEROP KERNELOP END(__copy_from_user_eva) -- GitLab