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-rw-r--r--arch/x86/lib/Makefile4
-rw-r--r--arch/x86/lib/copy_user_64.S429
-rw-r--r--arch/x86/lib/copy_user_nocache_64.S283
-rw-r--r--arch/x86/lib/delay.c (renamed from arch/x86/lib/delay_32.c)38
-rw-r--r--arch/x86/lib/delay_64.c85
-rw-r--r--arch/x86/lib/getuser.S (renamed from arch/x86/lib/getuser_64.S)87
-rw-r--r--arch/x86/lib/getuser_32.S78
-rw-r--r--arch/x86/lib/putuser.S (renamed from arch/x86/lib/putuser_32.S)73
-rw-r--r--arch/x86/lib/putuser_64.S106
-rw-r--r--arch/x86/lib/usercopy_64.c23
10 files changed, 400 insertions, 806 deletions
diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile
index 76f60f52a88..83226e0a7ce 100644
--- a/arch/x86/lib/Makefile
+++ b/arch/x86/lib/Makefile
@@ -4,8 +4,8 @@
obj-$(CONFIG_SMP) := msr-on-cpu.o
-lib-y := delay_$(BITS).o
-lib-y += usercopy_$(BITS).o getuser_$(BITS).o putuser_$(BITS).o
+lib-y := delay.o
+lib-y += usercopy_$(BITS).o getuser.o putuser.o
lib-y += memcpy_$(BITS).o
ifeq ($(CONFIG_X86_32),y)
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index ee1c3f63515..dfdf428975c 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -1,8 +1,10 @@
-/* Copyright 2002 Andi Kleen, SuSE Labs.
+/*
+ * Copyright 2008 Vitaly Mayatskikh <vmayatsk@redhat.com>
+ * Copyright 2002 Andi Kleen, SuSE Labs.
* Subject to the GNU Public License v2.
- *
- * Functions to copy from and to user space.
- */
+ *
+ * Functions to copy from and to user space.
+ */
#include <linux/linkage.h>
#include <asm/dwarf2.h>
@@ -20,60 +22,88 @@
.long \orig-1f /* by default jump to orig */
1:
.section .altinstr_replacement,"ax"
-2: .byte 0xe9 /* near jump with 32bit immediate */
+2: .byte 0xe9 /* near jump with 32bit immediate */
.long \alt-1b /* offset */ /* or alternatively to alt */
.previous
.section .altinstructions,"a"
.align 8
.quad 0b
.quad 2b
- .byte \feature /* when feature is set */
+ .byte \feature /* when feature is set */
.byte 5
.byte 5
.previous
.endm
-/* Standard copy_to_user with segment limit checking */
+ .macro ALIGN_DESTINATION
+#ifdef FIX_ALIGNMENT
+ /* check for bad alignment of destination */
+ movl %edi,%ecx
+ andl $7,%ecx
+ jz 102f /* already aligned */
+ subl $8,%ecx
+ negl %ecx
+ subl %ecx,%edx
+100: movb (%rsi),%al
+101: movb %al,(%rdi)
+ incq %rsi
+ incq %rdi
+ decl %ecx
+ jnz 100b
+102:
+ .section .fixup,"ax"
+103: addl %r8d,%edx /* ecx is zerorest also */
+ jmp copy_user_handle_tail
+ .previous
+
+ .section __ex_table,"a"
+ .align 8
+ .quad 100b,103b
+ .quad 101b,103b
+ .previous
+#endif
+ .endm
+
+/* Standard copy_to_user with segment limit checking */
ENTRY(copy_to_user)
CFI_STARTPROC
GET_THREAD_INFO(%rax)
movq %rdi,%rcx
addq %rdx,%rcx
- jc bad_to_user
- cmpq threadinfo_addr_limit(%rax),%rcx
+ jc bad_to_user
+ cmpq TI_addr_limit(%rax),%rcx
jae bad_to_user
- xorl %eax,%eax /* clear zero flag */
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
-ENTRY(copy_user_generic)
+/* Standard copy_from_user with segment limit checking */
+ENTRY(copy_from_user)
CFI_STARTPROC
- movl $1,%ecx /* set zero flag */
+ GET_THREAD_INFO(%rax)
+ movq %rsi,%rcx
+ addq %rdx,%rcx
+ jc bad_from_user
+ cmpq TI_addr_limit(%rax),%rcx
+ jae bad_from_user
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
+ENDPROC(copy_from_user)
-ENTRY(__copy_from_user_inatomic)
+ENTRY(copy_user_generic)
CFI_STARTPROC
- xorl %ecx,%ecx /* clear zero flag */
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
+ENDPROC(copy_user_generic)
-/* Standard copy_from_user with segment limit checking */
-ENTRY(copy_from_user)
+ENTRY(__copy_from_user_inatomic)
CFI_STARTPROC
- GET_THREAD_INFO(%rax)
- movq %rsi,%rcx
- addq %rdx,%rcx
- jc bad_from_user
- cmpq threadinfo_addr_limit(%rax),%rcx
- jae bad_from_user
- movl $1,%ecx /* set zero flag */
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
-ENDPROC(copy_from_user)
-
+ENDPROC(__copy_from_user_inatomic)
+
.section .fixup,"ax"
/* must zero dest */
+ENTRY(bad_from_user)
bad_from_user:
CFI_STARTPROC
movl %edx,%ecx
@@ -81,271 +111,158 @@ bad_from_user:
rep
stosb
bad_to_user:
- movl %edx,%eax
+ movl %edx,%eax
ret
CFI_ENDPROC
-END(bad_from_user)
+ENDPROC(bad_from_user)
.previous
-
-
+
/*
* copy_user_generic_unrolled - memory copy with exception handling.
- * This version is for CPUs like P4 that don't have efficient micro code for rep movsq
- *
- * Input:
+ * This version is for CPUs like P4 that don't have efficient micro
+ * code for rep movsq
+ *
+ * Input:
* rdi destination
* rsi source
* rdx count
- * ecx zero flag -- if true zero destination on error
*
- * Output:
- * eax uncopied bytes or 0 if successful.
+ * Output:
+ * eax uncopied bytes or 0 if successfull.
*/
ENTRY(copy_user_generic_unrolled)
CFI_STARTPROC
- pushq %rbx
- CFI_ADJUST_CFA_OFFSET 8
- CFI_REL_OFFSET rbx, 0
- pushq %rcx
- 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: movq %r11,(%rdi)
-.Ld2: movq %r8,1*8(%rdi)
-.Ld3: movq %r9,2*8(%rdi)
-.Ld4: movq %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: movq %r11,4*8(%rdi)
-.Ld6: movq %r8,5*8(%rdi)
-.Ld7: movq %r9,6*8(%rdi)
-.Ld8: movq %r10,7*8(%rdi)
-
- decq %rdx
-
+ 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: movq %r8,(%rdi)
+6: movq %r9,1*8(%rdi)
+7: movq %r10,2*8(%rdi)
+8: movq %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: movq %r8,4*8(%rdi)
+14: movq %r9,5*8(%rdi)
+15: movq %r10,6*8(%rdi)
+16: movq %r11,7*8(%rdi)
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: movq %r8,(%rdi)
decl %ecx
- leaq 8(%rdi),%rdi
+ jnz 1b
+17: movl %edx,%ecx
+ andl $7,%edx
+ shrl $3,%ecx
+ jz 20f
+18: movq (%rsi),%r8
+19: movq %r8,(%rdi)
leaq 8(%rsi),%rsi
- jnz .Lloop_8
-
-.Lhandle_7:
+ leaq 8(%rdi),%rdi
+ decl %ecx
+ jnz 18b
+20: andl %edx,%edx
+ jz 23f
movl %edx,%ecx
- andl $7,%ecx
- jz .Lende
- .p2align 4
-.Lloop_1:
-.Ls10: movb (%rsi),%bl
-.Ld10: movb %bl,(%rdi)
- incq %rdi
+21: movb (%rsi),%al
+22: movb %al,(%rdi)
incq %rsi
+ incq %rdi
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
+ jnz 21b
+23: xor %eax,%eax
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
+ .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: jmp copy_user_handle_tail /* ecx is zerorest also */
+ .previous
- /* table sorted by exception address */
.section __ex_table,"a"
.align 8
- .quad .Ls1,.Ls1e /* Ls1-Ls4 have copied zero bytes */
- .quad .Ls2,.Ls1e
- .quad .Ls3,.Ls1e
- .quad .Ls4,.Ls1e
- .quad .Ld1,.Ls1e /* Ld1-Ld4 have copied 0-24 bytes */
- .quad .Ld2,.Ls2e
- .quad .Ld3,.Ls3e
- .quad .Ld4,.Ls4e
- .quad .Ls5,.Ls5e /* Ls5-Ls8 have copied 32 bytes */
- .quad .Ls6,.Ls5e
- .quad .Ls7,.Ls5e
- .quad .Ls8,.Ls5e
- .quad .Ld5,.Ls5e /* Ld5-Ld8 have copied 32-56 bytes */
- .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
+ .quad 1b,30b
+ .quad 2b,30b
+ .quad 3b,30b
+ .quad 4b,30b
+ .quad 5b,30b
+ .quad 6b,30b
+ .quad 7b,30b
+ .quad 8b,30b
+ .quad 9b,30b
+ .quad 10b,30b
+ .quad 11b,30b
+ .quad 12b,30b
+ .quad 13b,30b
+ .quad 14b,30b
+ .quad 15b,30b
+ .quad 16b,30b
+ .quad 18b,40b
+ .quad 19b,40b
+ .quad 21b,50b
+ .quad 22b,50b
.previous
-
- /* eax: zero, ebx: 64 */
-.Ls1e: addl $8,%eax /* eax is bytes left uncopied within the loop (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)
- 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_generic)
+ENDPROC(copy_user_generic_unrolled)
-
- /* Some CPUs run faster using the string copy instructions.
- This is also a lot simpler. Use them when possible.
- Patch in jmps to this code instead of copying it fully
- to avoid unwanted aliasing in the exception tables. */
-
- /* rdi destination
- * rsi source
- * rdx count
- * ecx zero flag
- *
- * Output:
- * eax uncopied bytes or 0 if successfull.
- *
- * Only 4GB of copy is supported. This shouldn't be a problem
- * because the kernel normally only writes from/to page sized chunks
- * even if user space passed a longer buffer.
- * And more would be dangerous because both Intel and AMD have
- * errata with rep movsq > 4GB. If someone feels the need to fix
- * this please consider this.
- */
+/* Some CPUs run faster using the string copy instructions.
+ * This is also a lot simpler. Use them when possible.
+ *
+ * Only 4GB of copy is supported. This shouldn't be a problem
+ * because the kernel normally only writes from/to page sized chunks
+ * even if user space passed a longer buffer.
+ * And more would be dangerous because both Intel and AMD have
+ * errata with rep movsq > 4GB. If someone feels the need to fix
+ * this please consider this.
+ *
+ * Input:
+ * rdi destination
+ * rsi source
+ * rdx count
+ *
+ * Output:
+ * eax uncopied bytes or 0 if successful.
+ */
ENTRY(copy_user_generic_string)
CFI_STARTPROC
- movl %ecx,%r8d /* save zero flag */
+ andl %edx,%edx
+ jz 4f
+ cmpl $8,%edx
+ jb 2f /* less than 8 bytes, go to byte copy loop */
+ ALIGN_DESTINATION
movl %edx,%ecx
shrl $3,%ecx
- andl $7,%edx
- jz 10f
-1: rep
- movsq
- movl %edx,%ecx
-2: rep
- movsb
-9: movl %ecx,%eax
- ret
-
- /* multiple of 8 byte */
-10: rep
+ andl $7,%edx
+1: rep
movsq
- xor %eax,%eax
+2: movl %edx,%ecx
+3: rep
+ movsb
+4: xorl %eax,%eax
ret
- /* exception handling */
-3: lea (%rdx,%rcx,8),%rax /* exception on quad loop */
- jmp 6f
-5: movl %ecx,%eax /* exception on byte loop */
- /* eax: left over bytes */
-6: testl %r8d,%r8d /* zero flag set? */
- jz 7f
- movl %eax,%ecx /* initialize x86 loop counter */
- push %rax
- xorl %eax,%eax
-8: rep
- stosb /* zero the rest */
-11: pop %rax
-7: ret
- CFI_ENDPROC
-END(copy_user_generic_c)
+ .section .fixup,"ax"
+11: lea (%rdx,%rcx,8),%rcx
+12: movl %ecx,%edx /* ecx is zerorest also */
+ jmp copy_user_handle_tail
+ .previous
.section __ex_table,"a"
- .quad 1b,3b
- .quad 2b,5b
- .quad 8b,11b
- .quad 10b,3b
+ .align 8
+ .quad 1b,11b
+ .quad 3b,12b
.previous
+ CFI_ENDPROC
+ENDPROC(copy_user_generic_string)
diff --git a/arch/x86/lib/copy_user_nocache_64.S b/arch/x86/lib/copy_user_nocache_64.S
index 9d3d1ab8376..40e0e309d27 100644
--- a/arch/x86/lib/copy_user_nocache_64.S
+++ b/arch/x86/lib/copy_user_nocache_64.S
@@ -1,4 +1,6 @@
-/* Copyright 2002 Andi Kleen, SuSE Labs.
+/*
+ * Copyright 2008 Vitaly Mayatskikh <vmayatsk@redhat.com>
+ * Copyright 2002 Andi Kleen, SuSE Labs.
* Subject to the GNU Public License v2.
*
* Functions to copy from and to user space.
@@ -12,204 +14,125 @@
#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 */
+ .macro ALIGN_DESTINATION
#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)
+ jz 102f /* already aligned */
+ subl $8,%ecx
+ negl %ecx
+ subl %ecx,%edx
+100: movb (%rsi),%al
+101: movb %al,(%rdi)
+ incq %rsi
+ incq %rdi
+ decl %ecx
+ jnz 100b
+102:
+ .section .fixup,"ax"
+103: addl %r8d,%edx /* ecx is zerorest also */
+ jmp copy_user_handle_tail
+ .previous
- dec %rdx
+ .section __ex_table,"a"
+ .align 8
+ .quad 100b,103b
+ .quad 101b,103b
+ .previous
+#endif
+ .endm
+/*
+ * 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
+ 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
-
- 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
+ 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
- jnz .Lloop_8
-
-.Lhandle_7:
+ leaq 8(%rdi),%rdi
+ decl %ecx
+ jnz 18b
+20: andl %edx,%edx
+ jz 23f
movl %edx,%ecx
- andl $7,%ecx
- jz .Lende
- .p2align 4
-.Lloop_1:
-.Ls10: movb (%rsi),%bl
-.Ld10: movb %bl,(%rdi)
- incq %rdi
+21: movb (%rsi),%al
+22: movb %al,(%rdi)
incq %rsi
+ incq %rdi
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
+ jnz 21b
+23: xorl %eax,%eax
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
+ .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
+ movl %r8d,%ecx
+ jmp copy_user_handle_tail
+ .previous
- /* 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
+ .quad 1b,30b
+ .quad 2b,30b
+ .quad 3b,30b
+ .quad 4b,30b
+ .quad 5b,30b
+ .quad 6b,30b
+ .quad 7b,30b
+ .quad 8b,30b
+ .quad 9b,30b
+ .quad 10b,30b
+ .quad 11b,30b
+ .quad 12b,30b
+ .quad 13b,30b
+ .quad 14b,30b
+ .quad 15b,30b
+ .quad 16b,30b
+ .quad 18b,40b
+ .quad 19b,40b
+ .quad 21b,50b
+ .quad 22b,50b
.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)
-
-
diff --git a/arch/x86/lib/delay_32.c b/arch/x86/lib/delay.c
index d710f2d167b..f4568605d7d 100644
--- a/arch/x86/lib/delay_32.c
+++ b/arch/x86/lib/delay.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 1993 Linus Torvalds
* Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
+ * Copyright (C) 2008 Jiri Hladky <hladky _dot_ jiri _at_ gmail _dot_ com>
*
* The __delay function must _NOT_ be inlined as its execution time
* depends wildly on alignment on many x86 processors. The additional
@@ -28,16 +29,22 @@
/* simple loop based delay: */
static void delay_loop(unsigned long loops)
{
- int d0;
-
- __asm__ __volatile__(
- "\tjmp 1f\n"
- ".align 16\n"
- "1:\tjmp 2f\n"
- ".align 16\n"
- "2:\tdecl %0\n\tjns 2b"
- :"=&a" (d0)
- :"0" (loops));
+ asm volatile(
+ " test %0,%0 \n"
+ " jz 3f \n"
+ " jmp 1f \n"
+
+ ".align 16 \n"
+ "1: jmp 2f \n"
+
+ ".align 16 \n"
+ "2: dec %0 \n"
+ " jnz 2b \n"
+ "3: dec %0 \n"
+
+ : /* we don't need output */
+ :"a" (loops)
+ );
}
/* TSC based delay: */
@@ -91,7 +98,7 @@ void use_tsc_delay(void)
int __devinit read_current_timer(unsigned long *timer_val)
{
if (delay_fn == delay_tsc) {
- rdtscl(*timer_val);
+ rdtscll(*timer_val);
return 0;
}
return -1;
@@ -101,31 +108,30 @@ void __delay(unsigned long loops)
{
delay_fn(loops);
}
+EXPORT_SYMBOL(__delay);
inline void __const_udelay(unsigned long xloops)
{
int d0;
xloops *= 4;
- __asm__("mull %0"
+ asm("mull %%edx"
:"=d" (xloops), "=&a" (d0)
:"1" (xloops), "0"
(cpu_data(raw_smp_processor_id()).loops_per_jiffy * (HZ/4)));
__delay(++xloops);
}
+EXPORT_SYMBOL(__const_udelay);
void __udelay(unsigned long usecs)
{
__const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
}
+EXPORT_SYMBOL(__udelay);
void __ndelay(unsigned long nsecs)
{
__const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
}
-
-EXPORT_SYMBOL(__delay);
-EXPORT_SYMBOL(__const_udelay);
-EXPORT_SYMBOL(__udelay);
EXPORT_SYMBOL(__ndelay);
diff --git a/arch/x86/lib/delay_64.c b/arch/x86/lib/delay_64.c
deleted file mode 100644
index 4c441be9264..00000000000
--- a/arch/x86/lib/delay_64.c
+++ /dev/null
@@ -1,85 +0,0 @@
-/*
- * Precise Delay Loops for x86-64
- *
- * Copyright (C) 1993 Linus Torvalds
- * Copyright (C) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
- *
- * The __delay function must _NOT_ be inlined as its execution time
- * depends wildly on alignment on many x86 processors.
- */
-
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/timex.h>
-#include <linux/preempt.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-
-#include <asm/delay.h>
-#include <asm/msr.h>
-
-#ifdef CONFIG_SMP
-#include <asm/smp.h>
-#endif
-
-int __devinit read_current_timer(unsigned long *timer_value)
-{
- rdtscll(*timer_value);
- return 0;
-}
-
-void __delay(unsigned long loops)
-{
- unsigned bclock, now;
- int cpu;
-
- preempt_disable();
- cpu = smp_processor_id();
- rdtscl(bclock);
- for (;;) {
- rdtscl(now);
- if ((now - bclock) >= loops)
- break;
-
- /* Allow RT tasks to run */
- preempt_enable();
- rep_nop();
- preempt_disable();
-
- /*
- * It is possible that we moved to another CPU, and
- * since TSC's are per-cpu we need to calculate
- * that. The delay must guarantee that we wait "at
- * least" the amount of time. Being moved to another
- * CPU could make the wait longer but we just need to
- * make sure we waited long enough. Rebalance the
- * counter for this CPU.
- */
- if (unlikely(cpu != smp_processor_id())) {
- loops -= (now - bclock);
- cpu = smp_processor_id();
- rdtscl(bclock);
- }
- }
- preempt_enable();
-}
-EXPORT_SYMBOL(__delay);
-
-inline void __const_udelay(unsigned long xloops)
-{
- __delay(((xloops * HZ *
- cpu_data(raw_smp_processor_id()).loops_per_jiffy) >> 32) + 1);
-}
-EXPORT_SYMBOL(__const_udelay);
-
-void __udelay(unsigned long usecs)
-{
- __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
-}
-EXPORT_SYMBOL(__udelay);
-
-void __ndelay(unsigned long nsecs)
-{
- __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
-}
-EXPORT_SYMBOL(__ndelay);
diff --git a/arch/x86/lib/getuser_64.S b/arch/x86/lib/getuser.S
index 5448876261f..ad374003742 100644
--- a/arch/x86/lib/getuser_64.S
+++ b/arch/x86/lib/getuser.S
@@ -3,6 +3,7 @@
*
* (C) Copyright 1998 Linus Torvalds
* (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
*
* These functions have a non-standard call interface
* to make them more efficient, especially as they
@@ -13,14 +14,13 @@
/*
* __get_user_X
*
- * Inputs: %rcx contains the address.
+ * Inputs: %[r|e]ax contains the address.
* The register is modified, but all changes are undone
* before returning because the C code doesn't know about it.
*
- * Outputs: %rax is error code (0 or -EFAULT)
- * %rdx contains zero-extended value
- *
- * %r8 is destroyed.
+ * Outputs: %[r|e]ax is error code (0 or -EFAULT)
+ * %[r|e]dx contains zero-extended value
+ *
*
* These functions should not modify any other registers,
* as they get called from within inline assembly.
@@ -32,78 +32,73 @@
#include <asm/errno.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
+#include <asm/asm.h>
.text
ENTRY(__get_user_1)
CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- cmpq threadinfo_addr_limit(%r8),%rcx
+ GET_THREAD_INFO(%_ASM_DX)
+ cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
jae bad_get_user
-1: movzb (%rcx),%edx
- xorl %eax,%eax
+1: movzb (%_ASM_AX),%edx
+ xor %eax,%eax
ret
CFI_ENDPROC
ENDPROC(__get_user_1)
ENTRY(__get_user_2)
CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $1,%rcx
- jc 20f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 20f
- decq %rcx
-2: movzwl (%rcx),%edx
- xorl %eax,%eax
+ add $1,%_ASM_AX
+ jc bad_get_user
+ GET_THREAD_INFO(%_ASM_DX)
+ cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+ jae bad_get_user
+2: movzwl -1(%_ASM_AX),%edx
+ xor %eax,%eax
ret
-20: decq %rcx
- jmp bad_get_user
CFI_ENDPROC
ENDPROC(__get_user_2)
ENTRY(__get_user_4)
CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $3,%rcx
- jc 30f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 30f
- subq $3,%rcx
-3: movl (%rcx),%edx
- xorl %eax,%eax
+ add $3,%_ASM_AX
+ jc bad_get_user
+ GET_THREAD_INFO(%_ASM_DX)
+ cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+ jae bad_get_user
+3: mov -3(%_ASM_AX),%edx
+ xor %eax,%eax
ret
-30: subq $3,%rcx
- jmp bad_get_user
CFI_ENDPROC
ENDPROC(__get_user_4)
+#ifdef CONFIG_X86_64
ENTRY(__get_user_8)
CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $7,%rcx
- jc 40f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 40f
- subq $7,%rcx
-4: movq (%rcx),%rdx
- xorl %eax,%eax
+ add $7,%_ASM_AX
+ jc bad_get_user
+ GET_THREAD_INFO(%_ASM_DX)
+ cmp TI_addr_limit(%_ASM_DX),%_ASM_AX
+ jae bad_get_user
+4: movq -7(%_ASM_AX),%_ASM_DX
+ xor %eax,%eax
ret
-40: subq $7,%rcx
- jmp bad_get_user
CFI_ENDPROC
ENDPROC(__get_user_8)
+#endif
bad_get_user:
CFI_STARTPROC
- xorl %edx,%edx
- movq $(-EFAULT),%rax
+ xor %edx,%edx
+ mov $(-EFAULT),%_ASM_AX
ret
CFI_ENDPROC
END(bad_get_user)
.section __ex_table,"a"
- .quad 1b,bad_get_user
- .quad 2b,bad_get_user
- .quad 3b,bad_get_user
- .quad 4b,bad_get_user
-.previous
+ _ASM_PTR 1b,bad_get_user
+ _ASM_PTR 2b,bad_get_user
+ _ASM_PTR 3b,bad_get_user
+#ifdef CONFIG_X86_64
+ _ASM_PTR 4b,bad_get_user
+#endif
diff --git a/arch/x86/lib/getuser_32.S b/arch/x86/lib/getuser_32.S
deleted file mode 100644
index 6d84b53f12a..00000000000
--- a/arch/x86/lib/getuser_32.S
+++ /dev/null
@@ -1,78 +0,0 @@
-/*
- * __get_user functions.
- *
- * (C) Copyright 1998 Linus Torvalds
- *
- * These functions have a non-standard call interface
- * to make them more efficient, especially as they
- * return an error value in addition to the "real"
- * return value.
- */
-#include <linux/linkage.h>
-#include <asm/dwarf2.h>
-#include <asm/thread_info.h>
-
-
-/*
- * __get_user_X
- *
- * Inputs: %eax contains the address
- *
- * Outputs: %eax is error code (0 or -EFAULT)
- * %edx contains zero-extended value
- *
- * These functions should not modify any other registers,
- * as they get called from within inline assembly.
- */
-
-.text
-ENTRY(__get_user_1)
- CFI_STARTPROC
- GET_THREAD_INFO(%edx)
- cmpl TI_addr_limit(%edx),%eax
- jae bad_get_user
-1: movzbl (%eax),%edx
- xorl %eax,%eax
- ret
- CFI_ENDPROC
-ENDPROC(__get_user_1)
-
-ENTRY(__get_user_2)
- CFI_STARTPROC
- addl $1,%eax
- jc bad_get_user
- GET_THREAD_INFO(%edx)
- cmpl TI_addr_limit(%edx),%eax
- jae bad_get_user
-2: movzwl -1(%eax),%edx
- xorl %eax,%eax
- ret
- CFI_ENDPROC
-ENDPROC(__get_user_2)
-
-ENTRY(__get_user_4)
- CFI_STARTPROC
- addl $3,%eax
- jc bad_get_user
- GET_THREAD_INFO(%edx)
- cmpl TI_addr_limit(%edx),%eax
- jae bad_get_user
-3: movl -3(%eax),%edx
- xorl %eax,%eax
- ret
- CFI_ENDPROC
-ENDPROC(__get_user_4)
-
-bad_get_user:
- CFI_STARTPROC
- xorl %edx,%edx
- movl $-14,%eax
- ret
- CFI_ENDPROC
-END(bad_get_user)
-
-.section __ex_table,"a"
- .long 1b,bad_get_user
- .long 2b,bad_get_user
- .long 3b,bad_get_user
-.previous
diff --git a/arch/x86/lib/putuser_32.S b/arch/x86/lib/putuser.S
index f58fba109d1..36b0d15ae6e 100644
--- a/arch/x86/lib/putuser_32.S
+++ b/arch/x86/lib/putuser.S
@@ -2,6 +2,8 @@
* __put_user functions.
*
* (C) Copyright 2005 Linus Torvalds
+ * (C) Copyright 2005 Andi Kleen
+ * (C) Copyright 2008 Glauber Costa
*
* These functions have a non-standard call interface
* to make them more efficient, especially as they
@@ -11,6 +13,8 @@
#include <linux/linkage.h>
#include <asm/dwarf2.h>
#include <asm/thread_info.h>
+#include <asm/errno.h>
+#include <asm/asm.h>
/*
@@ -26,73 +30,68 @@
*/
#define ENTER CFI_STARTPROC ; \
- pushl %ebx ; \
- CFI_ADJUST_CFA_OFFSET 4 ; \
- CFI_REL_OFFSET ebx, 0 ; \
- GET_THREAD_INFO(%ebx)
-#define EXIT popl %ebx ; \
- CFI_ADJUST_CFA_OFFSET -4 ; \
- CFI_RESTORE ebx ; \
- ret ; \
+ GET_THREAD_INFO(%_ASM_BX)
+#define EXIT ret ; \
CFI_ENDPROC
.text
ENTRY(__put_user_1)
ENTER
- cmpl TI_addr_limit(%ebx),%ecx
+ cmp TI_addr_limit(%_ASM_BX),%_ASM_CX
jae bad_put_user
-1: movb %al,(%ecx)
- xorl %eax,%eax
+1: movb %al,(%_ASM_CX)
+ xor %eax,%eax
EXIT
ENDPROC(__put_user_1)
ENTRY(__put_user_2)
ENTER
- movl TI_addr_limit(%ebx),%ebx
- subl $1,%ebx
- cmpl %ebx,%ecx
+ mov TI_addr_limit(%_ASM_BX),%_ASM_BX
+ sub $1,%_ASM_BX
+ cmp %_ASM_BX,%_ASM_CX
jae bad_put_user
-2: movw %ax,(%ecx)
- xorl %eax,%eax
+2: movw %ax,(%_ASM_CX)
+ xor %eax,%eax
EXIT
ENDPROC(__put_user_2)
ENTRY(__put_user_4)
ENTER
- movl TI_addr_limit(%ebx),%ebx
- subl $3,%ebx
- cmpl %ebx,%ecx
+ mov TI_addr_limit(%_ASM_BX),%_ASM_BX
+ sub $3,%_ASM_BX
+ cmp %_ASM_BX,%_ASM_CX
jae bad_put_user
-3: movl %eax,(%ecx)
- xorl %eax,%eax
+3: movl %eax,(%_ASM_CX)
+ xor %eax,%eax
EXIT
ENDPROC(__put_user_4)
ENTRY(__put_user_8)
ENTER
- movl TI_addr_limit(%ebx),%ebx
- subl $7,%ebx
- cmpl %ebx,%ecx
+ mov TI_addr_limit(%_ASM_BX),%_ASM_BX
+ sub $7,%_ASM_BX
+ cmp %_ASM_BX,%_ASM_CX
jae bad_put_user
-4: movl %eax,(%ecx)
-5: movl %edx,4(%ecx)
- xorl %eax,%eax
+4: mov %_ASM_AX,(%_ASM_CX)
+#ifdef CONFIG_X86_32
+5: movl %edx,4(%_ASM_CX)
+#endif
+ xor %eax,%eax
EXIT
ENDPROC(__put_user_8)
bad_put_user:
- CFI_STARTPROC simple
- CFI_DEF_CFA esp, 2*4
- CFI_OFFSET eip, -1*4
- CFI_OFFSET ebx, -2*4
- movl $-14,%eax
+ CFI_STARTPROC
+ movl $-EFAULT,%eax
EXIT
END(bad_put_user)
.section __ex_table,"a"
- .long 1b,bad_put_user
- .long 2b,bad_put_user
- .long 3b,bad_put_user
- .long 4b,bad_put_user
- .long 5b,bad_put_user
+ _ASM_PTR 1b,bad_put_user
+ _ASM_PTR 2b,bad_put_user
+ _ASM_PTR 3b,bad_put_user
+ _ASM_PTR 4b,bad_put_user
+#ifdef CONFIG_X86_32
+ _ASM_PTR 5b,bad_put_user
+#endif
.previous
diff --git a/arch/x86/lib/putuser_64.S b/arch/x86/lib/putuser_64.S
deleted file mode 100644
index 4989f5a8fa9..00000000000
--- a/arch/x86/lib/putuser_64.S
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * __put_user functions.
- *
- * (C) Copyright 1998 Linus Torvalds
- * (C) Copyright 2005 Andi Kleen
- *
- * These functions have a non-standard call interface
- * to make them more efficient, especially as they
- * return an error value in addition to the "real"
- * return value.
- */
-
-/*
- * __put_user_X
- *
- * Inputs: %rcx contains the address
- * %rdx contains new value
- *
- * Outputs: %rax is error code (0 or -EFAULT)
- *
- * %r8 is destroyed.
- *
- * These functions should not modify any other registers,
- * as they get called from within inline assembly.
- */
-
-#include <linux/linkage.h>
-#include <asm/dwarf2.h>
-#include <asm/page.h>
-#include <asm/errno.h>
-#include <asm/asm-offsets.h>
-#include <asm/thread_info.h>
-
- .text
-ENTRY(__put_user_1)
- CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae bad_put_user
-1: movb %dl,(%rcx)
- xorl %eax,%eax
- ret
- CFI_ENDPROC
-ENDPROC(__put_user_1)
-
-ENTRY(__put_user_2)
- CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $1,%rcx
- jc 20f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 20f
- decq %rcx
-2: movw %dx,(%rcx)
- xorl %eax,%eax
- ret
-20: decq %rcx
- jmp bad_put_user
- CFI_ENDPROC
-ENDPROC(__put_user_2)
-
-ENTRY(__put_user_4)
- CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $3,%rcx
- jc 30f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 30f
- subq $3,%rcx
-3: movl %edx,(%rcx)
- xorl %eax,%eax
- ret
-30: subq $3,%rcx
- jmp bad_put_user
- CFI_ENDPROC
-ENDPROC(__put_user_4)
-
-ENTRY(__put_user_8)
- CFI_STARTPROC
- GET_THREAD_INFO(%r8)
- addq $7,%rcx
- jc 40f
- cmpq threadinfo_addr_limit(%r8),%rcx
- jae 40f
- subq $7,%rcx
-4: movq %rdx,(%rcx)
- xorl %eax,%eax
- ret
-40: subq $7,%rcx
- jmp bad_put_user
- CFI_ENDPROC
-ENDPROC(__put_user_8)
-
-bad_put_user:
- CFI_STARTPROC
- movq $(-EFAULT),%rax
- ret
- CFI_ENDPROC
-END(bad_put_user)
-
-.section __ex_table,"a"
- .quad 1b,bad_put_user
- .quad 2b,bad_put_user
- .quad 3b,bad_put_user
- .quad 4b,bad_put_user
-.previous
diff --git a/arch/x86/lib/usercopy_64.c b/arch/x86/lib/usercopy_64.c
index 0c89d1bb028..f4df6e7c718 100644
--- a/arch/x86/lib/usercopy_64.c
+++ b/arch/x86/lib/usercopy_64.c
@@ -158,3 +158,26 @@ unsigned long copy_in_user(void __user *to, const void __user *from, unsigned le
}
EXPORT_SYMBOL(copy_in_user);
+/*
+ * Try to copy last bytes and clear the rest if needed.
+ * Since protection fault in copy_from/to_user is not a normal situation,
+ * it is not necessary to optimize tail handling.
+ */
+unsigned long
+copy_user_handle_tail(char *to, char *from, unsigned len, unsigned zerorest)
+{
+ char c;
+ unsigned zero_len;
+
+ for (; len; --len) {
+ if (__get_user_nocheck(c, from++, sizeof(char)))
+ break;
+ if (__put_user_nocheck(c, to++, sizeof(char)))
+ break;
+ }
+
+ for (c = 0, zero_len = len; zerorest && zero_len; --zero_len)
+ if (__put_user_nocheck(c, to++, sizeof(char)))
+ break;
+ return len;
+}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-04 12:25:26 +0000