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authorBorislav Petkov <bp@suse.de>2015-05-13 20:42:24 +0300
committerIngo Molnar <mingo@kernel.org>2015-05-14 08:25:35 +0300
commitb41e6ec242cba0151f0b32041cfa728e7ca6e0b7 (patch)
tree0b8a9f0c0aeb0dd11af99bfed4d8972baa3e7b5a /arch/x86/lib/copy_user_64.S
parent9e6b13f761d5914a8c9b83610e8d459653515c94 (diff)
downloadlinux-b41e6ec242cba0151f0b32041cfa728e7ca6e0b7.tar.xz
x86/asm/uaccess: Get rid of copy_user_nocache_64.S
Move __copy_user_nocache() to arch/x86/lib/copy_user_64.S and kill the containing file. No functionality change. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1431538944-27724-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/lib/copy_user_64.S')
-rw-r--r--arch/x86/lib/copy_user_64.S92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index 06ce685c3a5d..e4b3beee83bd 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -242,3 +242,95 @@ ENTRY(copy_user_enhanced_fast_string)
_ASM_EXTABLE(1b,12b)
CFI_ENDPROC
ENDPROC(copy_user_enhanced_fast_string)
+
+/*
+ * copy_user_nocache - Uncached memory copy with exception handling
+ * This will force destination/source out of cache for more performance.
+ */
+ENTRY(__copy_user_nocache)
+ CFI_STARTPROC
+ ASM_STAC
+ cmpl $8,%edx
+ jb 20f /* less then 8 bytes, go to byte copy loop */
+ ALIGN_DESTINATION
+ movl %edx,%ecx
+ andl $63,%edx
+ shrl $6,%ecx
+ jz 17f
+1: movq (%rsi),%r8
+2: movq 1*8(%rsi),%r9
+3: movq 2*8(%rsi),%r10
+4: movq 3*8(%rsi),%r11
+5: movnti %r8,(%rdi)
+6: movnti %r9,1*8(%rdi)
+7: movnti %r10,2*8(%rdi)
+8: movnti %r11,3*8(%rdi)
+9: movq 4*8(%rsi),%r8
+10: movq 5*8(%rsi),%r9
+11: movq 6*8(%rsi),%r10
+12: movq 7*8(%rsi),%r11
+13: movnti %r8,4*8(%rdi)
+14: movnti %r9,5*8(%rdi)
+15: movnti %r10,6*8(%rdi)
+16: movnti %r11,7*8(%rdi)
+ leaq 64(%rsi),%rsi
+ leaq 64(%rdi),%rdi
+ decl %ecx
+ jnz 1b
+17: movl %edx,%ecx
+ andl $7,%edx
+ shrl $3,%ecx
+ jz 20f
+18: movq (%rsi),%r8
+19: movnti %r8,(%rdi)
+ leaq 8(%rsi),%rsi
+ leaq 8(%rdi),%rdi
+ decl %ecx
+ jnz 18b
+20: andl %edx,%edx
+ jz 23f
+ movl %edx,%ecx
+21: movb (%rsi),%al
+22: movb %al,(%rdi)
+ incq %rsi
+ incq %rdi
+ decl %ecx
+ jnz 21b
+23: xorl %eax,%eax
+ ASM_CLAC
+ sfence
+ ret
+
+ .section .fixup,"ax"
+30: shll $6,%ecx
+ addl %ecx,%edx
+ jmp 60f
+40: lea (%rdx,%rcx,8),%rdx
+ jmp 60f
+50: movl %ecx,%edx
+60: sfence
+ jmp copy_user_handle_tail
+ .previous
+
+ _ASM_EXTABLE(1b,30b)
+ _ASM_EXTABLE(2b,30b)
+ _ASM_EXTABLE(3b,30b)
+ _ASM_EXTABLE(4b,30b)
+ _ASM_EXTABLE(5b,30b)
+ _ASM_EXTABLE(6b,30b)
+ _ASM_EXTABLE(7b,30b)
+ _ASM_EXTABLE(8b,30b)
+ _ASM_EXTABLE(9b,30b)
+ _ASM_EXTABLE(10b,30b)
+ _ASM_EXTABLE(11b,30b)
+ _ASM_EXTABLE(12b,30b)
+ _ASM_EXTABLE(13b,30b)
+ _ASM_EXTABLE(14b,30b)
+ _ASM_EXTABLE(15b,30b)
+ _ASM_EXTABLE(16b,30b)
+ _ASM_EXTABLE(18b,40b)
+ _ASM_EXTABLE(19b,40b)
+ _ASM_EXTABLE(21b,50b)
+ _ASM_EXTABLE(22b,50b)
+ CFI_ENDPROC
+ENDPROC(__copy_user_nocache)