[PATCH 2/3] Fix copy_user on x86_64

From: Vitaly Mayatskikh
Date: Fri Jun 27 2008 - 17:55:23 EST


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