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-rw-r--r--arch/x86/kernel/x8664_ksyms_64.c1
-rw-r--r--arch/x86/lib/memmove_64.S197
-rw-r--r--arch/x86/lib/memmove_64.c192
3 files changed, 198 insertions, 192 deletions
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c
index 1b950d151e58..9796c2f3d074 100644
--- a/arch/x86/kernel/x8664_ksyms_64.c
+++ b/arch/x86/kernel/x8664_ksyms_64.c
@@ -52,6 +52,7 @@ extern void *__memcpy(void *, const void *, __kernel_size_t);
EXPORT_SYMBOL(memset);
EXPORT_SYMBOL(memcpy);
EXPORT_SYMBOL(__memcpy);
+EXPORT_SYMBOL(memmove);
EXPORT_SYMBOL(empty_zero_page);
#ifndef CONFIG_PARAVIRT
diff --git a/arch/x86/lib/memmove_64.S b/arch/x86/lib/memmove_64.S
new file mode 100644
index 000000000000..0ecb8433e5a8
--- /dev/null
+++ b/arch/x86/lib/memmove_64.S
@@ -0,0 +1,197 @@
+/*
+ * Normally compiler builtins are used, but sometimes the compiler calls out
+ * of line code. Based on asm-i386/string.h.
+ *
+ * This assembly file is re-written from memmove_64.c file.
+ * - Copyright 2011 Fenghua Yu <fenghua.yu@intel.com>
+ */
+#define _STRING_C
+#include <linux/linkage.h>
+#include <asm/dwarf2.h>
+
+#undef memmove
+
+/*
+ * Implement memmove(). This can handle overlap between src and dst.
+ *
+ * Input:
+ * rdi: dest
+ * rsi: src
+ * rdx: count
+ *
+ * Output:
+ * rax: dest
+ */
+ENTRY(memmove)
+ CFI_STARTPROC
+ /* Handle more 32bytes in loop */
+ mov %rdi, %rax
+ cmp $0x20, %rdx
+ jb 1f
+
+ /* Decide forward/backward copy mode */
+ cmp %rdi, %rsi
+ jb 2f
+
+ /*
+ * movsq instruction have many startup latency
+ * so we handle small size by general register.
+ */
+ cmp $680, %rdx
+ jb 3f
+ /*
+ * movsq instruction is only good for aligned case.
+ */
+
+ cmpb %dil, %sil
+ je 4f
+3:
+ sub $0x20, %rdx
+ /*
+ * We gobble 32byts forward in each loop.
+ */
+5:
+ sub $0x20, %rdx
+ movq 0*8(%rsi), %r11
+ movq 1*8(%rsi), %r10
+ movq 2*8(%rsi), %r9
+ movq 3*8(%rsi), %r8
+ leaq 4*8(%rsi), %rsi
+
+ movq %r11, 0*8(%rdi)
+ movq %r10, 1*8(%rdi)
+ movq %r9, 2*8(%rdi)
+ movq %r8, 3*8(%rdi)
+ leaq 4*8(%rdi), %rdi
+ jae 5b
+ addq $0x20, %rdx
+ jmp 1f
+ /*
+ * Handle data forward by movsq.
+ */
+ .p2align 4
+4:
+ movq %rdx, %rcx
+ movq -8(%rsi, %rdx), %r11
+ lea -8(%rdi, %rdx), %r10
+ shrq $3, %rcx
+ rep movsq
+ movq %r11, (%r10)
+ jmp 13f
+ /*
+ * Handle data backward by movsq.
+ */
+ .p2align 4
+7:
+ movq %rdx, %rcx
+ movq (%rsi), %r11
+ movq %rdi, %r10
+ leaq -8(%rsi, %rdx), %rsi
+ leaq -8(%rdi, %rdx), %rdi
+ shrq $3, %rcx
+ std
+ rep movsq
+ cld
+ movq %r11, (%r10)
+ jmp 13f
+
+ /*
+ * Start to prepare for backward copy.
+ */
+ .p2align 4
+2:
+ cmp $680, %rdx
+ jb 6f
+ cmp %dil, %sil
+ je 7b
+6:
+ /*
+ * Calculate copy position to tail.
+ */
+ addq %rdx, %rsi
+ addq %rdx, %rdi
+ subq $0x20, %rdx
+ /*
+ * We gobble 32byts backward in each loop.
+ */
+8:
+ subq $0x20, %rdx
+ movq -1*8(%rsi), %r11
+ movq -2*8(%rsi), %r10
+ movq -3*8(%rsi), %r9
+ movq -4*8(%rsi), %r8
+ leaq -4*8(%rsi), %rsi
+
+ movq %r11, -1*8(%rdi)
+ movq %r10, -2*8(%rdi)
+ movq %r9, -3*8(%rdi)
+ movq %r8, -4*8(%rdi)
+ leaq -4*8(%rdi), %rdi
+ jae 8b
+ /*
+ * Calculate copy position to head.
+ */
+ addq $0x20, %rdx
+ subq %rdx, %rsi
+ subq %rdx, %rdi
+1:
+ cmpq $16, %rdx
+ jb 9f
+ /*
+ * Move data from 16 bytes to 31 bytes.
+ */
+ movq 0*8(%rsi), %r11
+ movq 1*8(%rsi), %r10
+ movq -2*8(%rsi, %rdx), %r9
+ movq -1*8(%rsi, %rdx), %r8
+ movq %r11, 0*8(%rdi)
+ movq %r10, 1*8(%rdi)
+ movq %r9, -2*8(%rdi, %rdx)
+ movq %r8, -1*8(%rdi, %rdx)
+ jmp 13f
+ .p2align 4
+9:
+ cmpq $8, %rdx
+ jb 10f
+ /*
+ * Move data from 8 bytes to 15 bytes.
+ */
+ movq 0*8(%rsi), %r11
+ movq -1*8(%rsi, %rdx), %r10
+ movq %r11, 0*8(%rdi)
+ movq %r10, -1*8(%rdi, %rdx)
+ jmp 13f
+10:
+ cmpq $4, %rdx
+ jb 11f
+ /*
+ * Move data from 4 bytes to 7 bytes.
+ */
+ movl (%rsi), %r11d
+ movl -4(%rsi, %rdx), %r10d
+ movl %r11d, (%rdi)
+ movl %r10d, -4(%rdi, %rdx)
+ jmp 13f
+11:
+ cmp $2, %rdx
+ jb 12f
+ /*
+ * Move data from 2 bytes to 3 bytes.
+ */
+ movw (%rsi), %r11w
+ movw -2(%rsi, %rdx), %r10w
+ movw %r11w, (%rdi)
+ movw %r10w, -2(%rdi, %rdx)
+ jmp 13f
+12:
+ cmp $1, %rdx
+ jb 13f
+ /*
+ * Move data for 1 byte.
+ */
+ movb (%rsi), %r11b
+ movb %r11b, (%rdi)
+13:
+ retq
+ CFI_ENDPROC
+ENDPROC(memmove)
diff --git a/arch/x86/lib/memmove_64.c b/arch/x86/lib/memmove_64.c
deleted file mode 100644
index 6d0f0ec41b34..000000000000
--- a/arch/x86/lib/memmove_64.c
+++ /dev/null
@@ -1,192 +0,0 @@
-/* Normally compiler builtins are used, but sometimes the compiler calls out
- of line code. Based on asm-i386/string.h.
- */
-#define _STRING_C
-#include <linux/string.h>
-#include <linux/module.h>
-
-#undef memmove
-void *memmove(void *dest, const void *src, size_t count)
-{
- unsigned long d0,d1,d2,d3,d4,d5,d6,d7;
- char *ret;
-
- __asm__ __volatile__(
- /* Handle more 32bytes in loop */
- "mov %2, %3\n\t"
- "cmp $0x20, %0\n\t"
- "jb 1f\n\t"
-
- /* Decide forward/backward copy mode */
- "cmp %2, %1\n\t"
- "jb 2f\n\t"
-
- /*
- * movsq instruction have many startup latency
- * so we handle small size by general register.
- */
- "cmp $680, %0\n\t"
- "jb 3f\n\t"
- /*
- * movsq instruction is only good for aligned case.
- */
- "cmpb %%dil, %%sil\n\t"
- "je 4f\n\t"
- "3:\n\t"
- "sub $0x20, %0\n\t"
- /*
- * We gobble 32byts forward in each loop.
- */
- "5:\n\t"
- "sub $0x20, %0\n\t"
- "movq 0*8(%1), %4\n\t"
- "movq 1*8(%1), %5\n\t"
- "movq 2*8(%1), %6\n\t"
- "movq 3*8(%1), %7\n\t"
- "leaq 4*8(%1), %1\n\t"
-
- "movq %4, 0*8(%2)\n\t"
- "movq %5, 1*8(%2)\n\t"
- "movq %6, 2*8(%2)\n\t"
- "movq %7, 3*8(%2)\n\t"
- "leaq 4*8(%2), %2\n\t"
- "jae 5b\n\t"
- "addq $0x20, %0\n\t"
- "jmp 1f\n\t"
- /*
- * Handle data forward by movsq.
- */
- ".p2align 4\n\t"
- "4:\n\t"
- "movq %0, %8\n\t"
- "movq -8(%1, %0), %4\n\t"
- "lea -8(%2, %0), %5\n\t"
- "shrq $3, %8\n\t"
- "rep movsq\n\t"
- "movq %4, (%5)\n\t"
- "jmp 13f\n\t"
- /*
- * Handle data backward by movsq.
- */
- ".p2align 4\n\t"
- "7:\n\t"
- "movq %0, %8\n\t"
- "movq (%1), %4\n\t"
- "movq %2, %5\n\t"
- "leaq -8(%1, %0), %1\n\t"
- "leaq -8(%2, %0), %2\n\t"
- "shrq $3, %8\n\t"
- "std\n\t"
- "rep movsq\n\t"
- "cld\n\t"
- "movq %4, (%5)\n\t"
- "jmp 13f\n\t"
-
- /*
- * Start to prepare for backward copy.
- */
- ".p2align 4\n\t"
- "2:\n\t"
- "cmp $680, %0\n\t"
- "jb 6f \n\t"
- "cmp %%dil, %%sil\n\t"
- "je 7b \n\t"
- "6:\n\t"
- /*
- * Calculate copy position to tail.
- */
- "addq %0, %1\n\t"
- "addq %0, %2\n\t"
- "subq $0x20, %0\n\t"
- /*
- * We gobble 32byts backward in each loop.
- */
- "8:\n\t"
- "subq $0x20, %0\n\t"
- "movq -1*8(%1), %4\n\t"
- "movq -2*8(%1), %5\n\t"
- "movq -3*8(%1), %6\n\t"
- "movq -4*8(%1), %7\n\t"
- "leaq -4*8(%1), %1\n\t"
-
- "movq %4, -1*8(%2)\n\t"
- "movq %5, -2*8(%2)\n\t"
- "movq %6, -3*8(%2)\n\t"
- "movq %7, -4*8(%2)\n\t"
- "leaq -4*8(%2), %2\n\t"
- "jae 8b\n\t"
- /*
- * Calculate copy position to head.
- */
- "addq $0x20, %0\n\t"
- "subq %0, %1\n\t"
- "subq %0, %2\n\t"
- "1:\n\t"
- "cmpq $16, %0\n\t"
- "jb 9f\n\t"
- /*
- * Move data from 16 bytes to 31 bytes.
- */
- "movq 0*8(%1), %4\n\t"
- "movq 1*8(%1), %5\n\t"
- "movq -2*8(%1, %0), %6\n\t"
- "movq -1*8(%1, %0), %7\n\t"
- "movq %4, 0*8(%2)\n\t"
- "movq %5, 1*8(%2)\n\t"
- "movq %6, -2*8(%2, %0)\n\t"
- "movq %7, -1*8(%2, %0)\n\t"
- "jmp 13f\n\t"
- ".p2align 4\n\t"
- "9:\n\t"
- "cmpq $8, %0\n\t"
- "jb 10f\n\t"
- /*
- * Move data from 8 bytes to 15 bytes.
- */
- "movq 0*8(%1), %4\n\t"
- "movq -1*8(%1, %0), %5\n\t"
- "movq %4, 0*8(%2)\n\t"
- "movq %5, -1*8(%2, %0)\n\t"
- "jmp 13f\n\t"
- "10:\n\t"
- "cmpq $4, %0\n\t"
- "jb 11f\n\t"
- /*
- * Move data from 4 bytes to 7 bytes.
- */
- "movl (%1), %4d\n\t"
- "movl -4(%1, %0), %5d\n\t"
- "movl %4d, (%2)\n\t"
- "movl %5d, -4(%2, %0)\n\t"
- "jmp 13f\n\t"
- "11:\n\t"
- "cmp $2, %0\n\t"
- "jb 12f\n\t"
- /*
- * Move data from 2 bytes to 3 bytes.
- */
- "movw (%1), %4w\n\t"
- "movw -2(%1, %0), %5w\n\t"
- "movw %4w, (%2)\n\t"
- "movw %5w, -2(%2, %0)\n\t"
- "jmp 13f\n\t"
- "12:\n\t"
- "cmp $1, %0\n\t"
- "jb 13f\n\t"
- /*
- * Move data for 1 byte.
- */
- "movb (%1), %4b\n\t"
- "movb %4b, (%2)\n\t"
- "13:\n\t"
- : "=&d" (d0), "=&S" (d1), "=&D" (d2), "=&a" (ret) ,
- "=r"(d3), "=r"(d4), "=r"(d5), "=r"(d6), "=&c" (d7)
- :"0" (count),
- "1" (src),
- "2" (dest)
- :"memory");
-
- return ret;
-
-}
-EXPORT_SYMBOL(memmove);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-18 17:00:01 +0000