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authorDavid Daney <david.daney@cavium.com>2012-06-06 18:00:31 -0400
committerRalf Baechle <ralf@linux-mips.org>2012-07-23 08:55:55 -0400
commitbb0757ebb929d5d6ba484b4313976847285ba280 (patch)
treef3a138d260d52fca71d7170e42415235ce6cc46b
parent914f848077fb2ec0ec9c041af9ae1101ed0320f3 (diff)
MIPS: Unify memcpy.S and memcpy-inatomic.S
We can save the 451 lines of code that comprise memcpy-inatomic.S at the expense of a single instruction in the memcpy prolog. We also use an additional register (t6), so this may cause increased register pressure in some places as well. But I think the reduced maintenance burden, of not having two nearly identical implementations, makes it worth it. Signed-off-by: David Daney <david.daney@cavium.com> Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat
-rw-r--r--arch/mips/include/asm/uaccess.h6
-rw-r--r--arch/mips/lib/Makefile2
-rw-r--r--arch/mips/lib/memcpy-inatomic.S451
-rw-r--r--arch/mips/lib/memcpy.S11
4 files changed, 15 insertions, 455 deletions
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index 653a412c036c..3b92efef56d3 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -687,7 +687,7 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n);
687 __MODULE_JAL(__copy_user) \ 687 __MODULE_JAL(__copy_user) \
688 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \ 688 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
689 : \ 689 : \
690 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \ 690 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
691 DADDI_SCRATCH, "memory"); \ 691 DADDI_SCRATCH, "memory"); \
692 __cu_len_r; \ 692 __cu_len_r; \
693}) 693})
@@ -797,7 +797,7 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
797 ".set\treorder" \ 797 ".set\treorder" \
798 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \ 798 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
799 : \ 799 : \
800 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \ 800 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
801 DADDI_SCRATCH, "memory"); \ 801 DADDI_SCRATCH, "memory"); \
802 __cu_len_r; \ 802 __cu_len_r; \
803}) 803})
@@ -820,7 +820,7 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
820 ".set\treorder" \ 820 ".set\treorder" \
821 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \ 821 : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
822 : \ 822 : \
823 : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \ 823 : "$8", "$9", "$10", "$11", "$12", "$14", "$15", "$24", "$31", \
824 DADDI_SCRATCH, "memory"); \ 824 DADDI_SCRATCH, "memory"); \
825 __cu_len_r; \ 825 __cu_len_r; \
826}) 826})
diff --git a/arch/mips/lib/Makefile b/arch/mips/lib/Makefile
index 2a7c74fc15fc..399a50a541d4 100644
--- a/arch/mips/lib/Makefile
+++ b/arch/mips/lib/Makefile
@@ -2,7 +2,7 @@
2# Makefile for MIPS-specific library files.. 2# Makefile for MIPS-specific library files..
3# 3#
4 4
5lib-y += csum_partial.o delay.o memcpy.o memcpy-inatomic.o memset.o \ 5lib-y += csum_partial.o delay.o memcpy.o memset.o \
6 strlen_user.o strncpy_user.o strnlen_user.o uncached.o 6 strlen_user.o strncpy_user.o strnlen_user.o uncached.o
7 7
8obj-y += iomap.o 8obj-y += iomap.o
diff --git a/arch/mips/lib/memcpy-inatomic.S b/arch/mips/lib/memcpy-inatomic.S
deleted file mode 100644
index 68853a038d3f..000000000000
--- a/arch/mips/lib/memcpy-inatomic.S
+++ /dev/null
@@ -1,451 +0,0 @@
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Unified implementation of memcpy, memmove and the __copy_user backend.
7 *
8 * Copyright (C) 1998, 99, 2000, 01, 2002 Ralf Baechle (ralf@gnu.org)
9 * Copyright (C) 1999, 2000, 01, 2002 Silicon Graphics, Inc.
10 * Copyright (C) 2002 Broadcom, Inc.
11 * memcpy/copy_user author: Mark Vandevoorde
12 * Copyright (C) 2007 Maciej W. Rozycki
13 *
14 * Mnemonic names for arguments to memcpy/__copy_user
15 */
16
17/*
18 * Hack to resolve longstanding prefetch issue
19 *
20 * Prefetching may be fatal on some systems if we're prefetching beyond the
21 * end of memory on some systems. It's also a seriously bad idea on non
22 * dma-coherent systems.
23 */
24#ifdef CONFIG_DMA_NONCOHERENT
25#undef CONFIG_CPU_HAS_PREFETCH
26#endif
27#ifdef CONFIG_MIPS_MALTA
28#undef CONFIG_CPU_HAS_PREFETCH
29#endif
30
31#include <asm/asm.h>
32#include <asm/asm-offsets.h>
33#include <asm/regdef.h>
34
35#define dst a0
36#define src a1
37#define len a2
38
39/*
40 * Spec
41 *
42 * memcpy copies len bytes from src to dst and sets v0 to dst.
43 * It assumes that
44 * - src and dst don't overlap
45 * - src is readable
46 * - dst is writable
47 * memcpy uses the standard calling convention
48 *
49 * __copy_user copies up to len bytes from src to dst and sets a2 (len) to
50 * the number of uncopied bytes due to an exception caused by a read or write.
51 * __copy_user assumes that src and dst don't overlap, and that the call is
52 * implementing one of the following:
53 * copy_to_user
54 * - src is readable (no exceptions when reading src)
55 * copy_from_user
56 * - dst is writable (no exceptions when writing dst)
57 * __copy_user uses a non-standard calling convention; see
58 * include/asm-mips/uaccess.h
59 *
60 * When an exception happens on a load, the handler must
61 # ensure that all of the destination buffer is overwritten to prevent
62 * leaking information to user mode programs.
63 */
64
65/*
66 * Implementation
67 */
68
69/*
70 * The exception handler for loads requires that:
71 * 1- AT contain the address of the byte just past the end of the source
72 * of the copy,
73 * 2- src_entry <= src < AT, and
74 * 3- (dst - src) == (dst_entry - src_entry),
75 * The _entry suffix denotes values when __copy_user was called.
76 *
77 * (1) is set up up by uaccess.h and maintained by not writing AT in copy_user
78 * (2) is met by incrementing src by the number of bytes copied
79 * (3) is met by not doing loads between a pair of increments of dst and src
80 *
81 * The exception handlers for stores adjust len (if necessary) and return.
82 * These handlers do not need to overwrite any data.
83 *
84 * For __rmemcpy and memmove an exception is always a kernel bug, therefore
85 * they're not protected.
86 */
87
88#define EXC(inst_reg,addr,handler) \
899: inst_reg, addr; \
90 .section __ex_table,"a"; \
91 PTR 9b, handler; \
92 .previous
93
94/*
95 * Only on the 64-bit kernel we can made use of 64-bit registers.
96 */
97#ifdef CONFIG_64BIT
98#define USE_DOUBLE
99#endif
100
101#ifdef USE_DOUBLE
102
103#define LOAD ld
104#define LOADL ldl
105#define LOADR ldr
106#define STOREL sdl
107#define STORER sdr
108#define STORE sd
109#define ADD daddu
110#define SUB dsubu
111#define SRL dsrl
112#define SRA dsra
113#define SLL dsll
114#define SLLV dsllv
115#define SRLV dsrlv
116#define NBYTES 8
117#define LOG_NBYTES 3
118
119/*
120 * As we are sharing code base with the mips32 tree (which use the o32 ABI
121 * register definitions). We need to redefine the register definitions from
122 * the n64 ABI register naming to the o32 ABI register naming.
123 */
124#undef t0
125#undef t1
126#undef t2
127#undef t3
128#define t0 $8
129#define t1 $9
130#define t2 $10
131#define t3 $11
132#define t4 $12
133#define t5 $13
134#define t6 $14
135#define t7 $15
136
137#else