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[PATCH 2/3] Fix copy_user on x86_64




Functionality of copy_user_nocache_64.S was moved to copy_user_64.c

diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 76f60f5..f3e844e 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -22,5 +22,5 @@ else
         lib-y += csum-partial_64.o csum-copy_64.o csum-wrappers_64.o
         lib-y += thunk_64.o clear_page_64.o copy_page_64.o
         lib-y += memmove_64.o memset_64.o
-        lib-y += copy_user_64.o rwlock_64.o copy_user_nocache_64.o
+        lib-y += copy_user_64.o rwlock_64.o
 endif
diff --git a/arch/x86/lib/copy_user_nocache_64.S b/arch/x86/lib/copy_user_nocache_64.S
deleted file mode 100644
index 9d3d1ab..0000000
--- a/arch/x86/lib/copy_user_nocache_64.S
+++ /dev/null
@@ -1,215 +0,0 @@
-/* Copyright 2002 Andi Kleen, SuSE Labs.
- * Subject to the GNU Public License v2.
- *
- * Functions to copy from and to user space.
- */
-
-#include <linux/linkage.h>
-#include <asm/dwarf2.h>
-
-#define FIX_ALIGNMENT 1
-
-#include <asm/current.h>
-#include <asm/asm-offsets.h>
-#include <asm/thread_info.h>
-#include <asm/cpufeature.h>
-
-/*
- * copy_user_nocache - Uncached memory copy with exception handling
- * This will force destination/source out of cache for more performance.
- *
- * Input:
- * rdi destination
- * rsi source
- * rdx count
- * rcx zero flag	when 1 zero on exception
- *
- * Output:
- * eax uncopied bytes or 0 if successful.
- */
-ENTRY(__copy_user_nocache)
-	CFI_STARTPROC
-	pushq %rbx
-	CFI_ADJUST_CFA_OFFSET 8
-	CFI_REL_OFFSET rbx, 0
-	pushq %rcx		/* save zero flag */
-	CFI_ADJUST_CFA_OFFSET 8
-	CFI_REL_OFFSET rcx, 0
-
-	xorl %eax,%eax		/* zero for the exception handler */
-
-#ifdef FIX_ALIGNMENT
-	/* check for bad alignment of destination */
-	movl %edi,%ecx
-	andl $7,%ecx
-	jnz  .Lbad_alignment
-.Lafter_bad_alignment:
-#endif
-
-	movq %rdx,%rcx
-
-	movl $64,%ebx
-	shrq $6,%rdx
-	decq %rdx
-	js   .Lhandle_tail
-
-	.p2align 4
-.Lloop:
-.Ls1:	movq (%rsi),%r11
-.Ls2:	movq 1*8(%rsi),%r8
-.Ls3:	movq 2*8(%rsi),%r9
-.Ls4:	movq 3*8(%rsi),%r10
-.Ld1:	movnti %r11,(%rdi)
-.Ld2:	movnti %r8,1*8(%rdi)
-.Ld3:	movnti %r9,2*8(%rdi)
-.Ld4:	movnti %r10,3*8(%rdi)
-
-.Ls5:	movq 4*8(%rsi),%r11
-.Ls6:	movq 5*8(%rsi),%r8
-.Ls7:	movq 6*8(%rsi),%r9
-.Ls8:	movq 7*8(%rsi),%r10
-.Ld5:	movnti %r11,4*8(%rdi)
-.Ld6:	movnti %r8,5*8(%rdi)
-.Ld7:	movnti %r9,6*8(%rdi)
-.Ld8:	movnti %r10,7*8(%rdi)
-
-	dec  %rdx
-
-	leaq 64(%rsi),%rsi
-	leaq 64(%rdi),%rdi
-
-	jns  .Lloop
-
-	.p2align 4
-.Lhandle_tail:
-	movl %ecx,%edx
-	andl $63,%ecx
-	shrl $3,%ecx
-	jz   .Lhandle_7
-	movl $8,%ebx
-	.p2align 4
-.Lloop_8:
-.Ls9:	movq (%rsi),%r8
-.Ld9:	movnti %r8,(%rdi)
-	decl %ecx
-	leaq 8(%rdi),%rdi
-	leaq 8(%rsi),%rsi
-	jnz .Lloop_8
-
-.Lhandle_7:
-	movl %edx,%ecx
-	andl $7,%ecx
-	jz   .Lende
-	.p2align 4
-.Lloop_1:
-.Ls10:	movb (%rsi),%bl
-.Ld10:	movb %bl,(%rdi)
-	incq %rdi
-	incq %rsi
-	decl %ecx
-	jnz .Lloop_1
-
-	CFI_REMEMBER_STATE
-.Lende:
-	popq %rcx
-	CFI_ADJUST_CFA_OFFSET -8
-	CFI_RESTORE %rcx
-	popq %rbx
-	CFI_ADJUST_CFA_OFFSET -8
-	CFI_RESTORE rbx
-	sfence
-	ret
-	CFI_RESTORE_STATE
-
-#ifdef FIX_ALIGNMENT
-	/* align destination */
-	.p2align 4
-.Lbad_alignment:
-	movl $8,%r9d
-	subl %ecx,%r9d
-	movl %r9d,%ecx
-	cmpq %r9,%rdx
-	jz   .Lhandle_7
-	js   .Lhandle_7
-.Lalign_1:
-.Ls11:	movb (%rsi),%bl
-.Ld11:	movb %bl,(%rdi)
-	incq %rsi
-	incq %rdi
-	decl %ecx
-	jnz .Lalign_1
-	subq %r9,%rdx
-	jmp .Lafter_bad_alignment
-#endif
-
-	/* table sorted by exception address */
-	.section __ex_table,"a"
-	.align 8
-	.quad .Ls1,.Ls1e	/* .Ls[1-4] - 0 bytes copied */
-	.quad .Ls2,.Ls1e
-	.quad .Ls3,.Ls1e
-	.quad .Ls4,.Ls1e
-	.quad .Ld1,.Ls1e	/* .Ld[1-4] - 0..24 bytes coped */
-	.quad .Ld2,.Ls2e
-	.quad .Ld3,.Ls3e
-	.quad .Ld4,.Ls4e
-	.quad .Ls5,.Ls5e	/* .Ls[5-8] - 32 bytes copied */
-	.quad .Ls6,.Ls5e
-	.quad .Ls7,.Ls5e
-	.quad .Ls8,.Ls5e
-	.quad .Ld5,.Ls5e	/* .Ld[5-8] - 32..56 bytes copied */
-	.quad .Ld6,.Ls6e
-	.quad .Ld7,.Ls7e
-	.quad .Ld8,.Ls8e
-	.quad .Ls9,.Le_quad
-	.quad .Ld9,.Le_quad
-	.quad .Ls10,.Le_byte
-	.quad .Ld10,.Le_byte
-#ifdef FIX_ALIGNMENT
-	.quad .Ls11,.Lzero_rest
-	.quad .Ld11,.Lzero_rest
-#endif
-	.quad .Le5,.Le_zero
-	.previous
-
-	/* eax: zero, ebx: 64 */
-.Ls1e: 	addl $8,%eax	/* eax: bytes left uncopied: Ls1e: 64 .. Ls8e: 8 */
-.Ls2e: 	addl $8,%eax
-.Ls3e: 	addl $8,%eax
-.Ls4e: 	addl $8,%eax
-.Ls5e: 	addl $8,%eax
-.Ls6e: 	addl $8,%eax
-.Ls7e: 	addl $8,%eax
-.Ls8e: 	addl $8,%eax
-	addq %rbx,%rdi	/* +64 */
-	subq %rax,%rdi  /* correct destination with computed offset */
-
-	shlq $6,%rdx	/* loop counter * 64 (stride length) */
-	addq %rax,%rdx	/* add offset to loopcnt */
-	andl $63,%ecx	/* remaining bytes */
-	addq %rcx,%rdx	/* add them */
-	jmp .Lzero_rest
-
-	/* exception on quad word loop in tail handling */
-	/* ecx:	loopcnt/8, %edx: length, rdi: correct */
-.Le_quad:
-	shll $3,%ecx
-	andl $7,%edx
-	addl %ecx,%edx
-	/* edx: bytes to zero, rdi: dest, eax:zero */
-.Lzero_rest:
-	cmpl $0,(%rsp)	/* zero flag set? */
-	jz   .Le_zero
-	movq %rdx,%rcx
-.Le_byte:
-	xorl %eax,%eax
-.Le5:	rep
-	stosb
-	/* when there is another exception while zeroing the rest just return */
-.Le_zero:
-	movq %rdx,%rax
-	jmp .Lende
-	CFI_ENDPROC
-ENDPROC(__copy_user_nocache)
-
-

Signed-off-by: Vitaly Mayatskikh <v.mayatskih@xxxxxxxxx>
-- 
wbr, Vitaly