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-rw-r--r--arch/tile/lib/atomic_32.c47
-rw-r--r--arch/tile/lib/exports.c8
-rw-r--r--arch/tile/lib/memchr_64.c8
-rw-r--r--arch/tile/lib/memcpy_64.c23
-rw-r--r--arch/tile/lib/memcpy_tile64.c8
-rw-r--r--arch/tile/lib/strchr_64.c15
-rw-r--r--arch/tile/lib/string-endian.h33
-rw-r--r--arch/tile/lib/strlen_64.c11
-rw-r--r--arch/tile/lib/usercopy_32.S76
-rw-r--r--arch/tile/lib/usercopy_64.S49
10 files changed, 71 insertions, 207 deletions
diff --git a/arch/tile/lib/atomic_32.c b/arch/tile/lib/atomic_32.c
index 771b251b409d..f5cada70c3c8 100644
--- a/arch/tile/lib/atomic_32.c
+++ b/arch/tile/lib/atomic_32.c
@@ -18,7 +18,6 @@
18#include <linux/module.h> 18#include <linux/module.h>
19#include <linux/mm.h> 19#include <linux/mm.h>
20#include <linux/atomic.h> 20#include <linux/atomic.h>
21#include <asm/futex.h>
22#include <arch/chip.h> 21#include <arch/chip.h>
23 22
24/* See <asm/atomic_32.h> */ 23/* See <asm/atomic_32.h> */
@@ -50,7 +49,7 @@ int atomic_locks[PAGE_SIZE / sizeof(int)] __page_aligned_bss;
50 49
51#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ 50#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */
52 51
53static inline int *__atomic_hashed_lock(volatile void *v) 52int *__atomic_hashed_lock(volatile void *v)
54{ 53{
55 /* NOTE: this code must match "sys_cmpxchg" in kernel/intvec_32.S */ 54 /* NOTE: this code must match "sys_cmpxchg" in kernel/intvec_32.S */
56#if ATOMIC_LOCKS_FOUND_VIA_TABLE() 55#if ATOMIC_LOCKS_FOUND_VIA_TABLE()
@@ -191,47 +190,6 @@ u64 _atomic64_cmpxchg(atomic64_t *v, u64 o, u64 n)
191EXPORT_SYMBOL(_atomic64_cmpxchg); 190EXPORT_SYMBOL(_atomic64_cmpxchg);
192 191
193 192
194static inline int *__futex_setup(int __user *v)
195{
196 /*
197 * Issue a prefetch to the counter to bring it into cache.
198 * As for __atomic_setup, but we can't do a read into the L1
199 * since it might fault; instead we do a prefetch into the L2.
200 */
201 __insn_prefetch(v);
202 return __atomic_hashed_lock((int __force *)v);
203}
204
205struct __get_user futex_set(u32 __user *v, int i)
206{
207 return __atomic_xchg((int __force *)v, __futex_setup(v), i);
208}
209
210struct __get_user futex_add(u32 __user *v, int n)
211{
212 return __atomic_xchg_add((int __force *)v, __futex_setup(v), n);
213}
214
215struct __get_user futex_or(u32 __user *v, int n)
216{
217 return __atomic_or((int __force *)v, __futex_setup(v), n);
218}
219
220struct __get_user futex_andn(u32 __user *v, int n)
221{
222 return __atomic_andn((int __force *)v, __futex_setup(v), n);
223}
224
225struct __get_user futex_xor(u32 __user *v, int n)
226{
227 return __atomic_xor((int __force *)v, __futex_setup(v), n);
228}
229
230struct __get_user futex_cmpxchg(u32 __user *v, int o, int n)
231{
232 return __atomic_cmpxchg((int __force *)v, __futex_setup(v), o, n);
233}
234
235/* 193/*
236 * If any of the atomic or futex routines hit a bad address (not in 194 * If any of the atomic or futex routines hit a bad address (not in
237 * the page tables at kernel PL) this routine is called. The futex 195 * the page tables at kernel PL) this routine is called. The futex
@@ -323,7 +281,4 @@ void __init __init_atomic_per_cpu(void)
323 BUILD_BUG_ON((PAGE_SIZE >> 3) > ATOMIC_HASH_SIZE); 281 BUILD_BUG_ON((PAGE_SIZE >> 3) > ATOMIC_HASH_SIZE);
324 282
325#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */ 283#endif /* ATOMIC_LOCKS_FOUND_VIA_TABLE() */
326
327 /* The futex code makes this assumption, so we validate it here. */
328 BUILD_BUG_ON(sizeof(atomic_t) != sizeof(int));
329} 284}
diff --git a/arch/tile/lib/exports.c b/arch/tile/lib/exports.c
index 2a81d32de0da..dd5f0a33fdaf 100644
--- a/arch/tile/lib/exports.c
+++ b/arch/tile/lib/exports.c
@@ -18,14 +18,6 @@
18 18
19/* arch/tile/lib/usercopy.S */ 19/* arch/tile/lib/usercopy.S */
20#include <linux/uaccess.h> 20#include <linux/uaccess.h>
21EXPORT_SYMBOL(__get_user_1);
22EXPORT_SYMBOL(__get_user_2);
23EXPORT_SYMBOL(__get_user_4);
24EXPORT_SYMBOL(__get_user_8);
25EXPORT_SYMBOL(__put_user_1);
26EXPORT_SYMBOL(__put_user_2);
27EXPORT_SYMBOL(__put_user_4);
28EXPORT_SYMBOL(__put_user_8);
29EXPORT_SYMBOL(strnlen_user_asm); 21EXPORT_SYMBOL(strnlen_user_asm);
30EXPORT_SYMBOL(strncpy_from_user_asm); 22EXPORT_SYMBOL(strncpy_from_user_asm);
31EXPORT_SYMBOL(clear_user_asm); 23EXPORT_SYMBOL(clear_user_asm);
diff --git a/arch/tile/lib/memchr_64.c b/arch/tile/lib/memchr_64.c
index 84fdc8d8e735..6f867dbf7c56 100644
--- a/arch/tile/lib/memchr_64.c
+++ b/arch/tile/lib/memchr_64.c
@@ -15,6 +15,7 @@
15#include <linux/types.h> 15#include <linux/types.h>
16#include <linux/string.h> 16#include <linux/string.h>
17#include <linux/module.h> 17#include <linux/module.h>
18#include "string-endian.h"
18 19
19void *memchr(const void *s, int c, size_t n) 20void *memchr(const void *s, int c, size_t n)
20{ 21{
@@ -39,11 +40,8 @@ void *memchr(const void *s, int c, size_t n)
39 40
40 /* Read the first word, but munge it so that bytes before the array 41 /* Read the first word, but munge it so that bytes before the array
41 * will not match goal. 42 * will not match goal.
42 *
43 * Note that this shift count expression works because we know
44 * shift counts are taken mod 64.
45 */ 43 */
46 before_mask = (1ULL << (s_int << 3)) - 1; 44 before_mask = MASK(s_int);
47 v = (*p | before_mask) ^ (goal & before_mask); 45 v = (*p | before_mask) ^ (goal & before_mask);
48 46
49 /* Compute the address of the last byte. */ 47 /* Compute the address of the last byte. */
@@ -65,7 +63,7 @@ void *memchr(const void *s, int c, size_t n)
65 /* We found a match, but it might be in a byte past the end 63 /* We found a match, but it might be in a byte past the end
66 * of the array. 64 * of the array.
67 */ 65 */
68 ret = ((char *)p) + (__insn_ctz(bits) >> 3); 66 ret = ((char *)p) + (CFZ(bits) >> 3);
69 return (ret <= last_byte_ptr) ? ret : NULL; 67 return (ret <= last_byte_ptr) ? ret : NULL;
70} 68}
71EXPORT_SYMBOL(memchr); 69EXPORT_SYMBOL(memchr);
diff --git a/arch/tile/lib/memcpy_64.c b/arch/tile/lib/memcpy_64.c
index 3fab9a6a2bbe..c79b8e7c6828 100644
--- a/arch/tile/lib/memcpy_64.c
+++ b/arch/tile/lib/memcpy_64.c
@@ -15,7 +15,6 @@
15#include <linux/types.h> 15#include <linux/types.h>
16#include <linux/string.h> 16#include <linux/string.h>
17#include <linux/module.h> 17#include <linux/module.h>
18#define __memcpy memcpy
19/* EXPORT_SYMBOL() is in arch/tile/lib/exports.c since this should be asm. */ 18/* EXPORT_SYMBOL() is in arch/tile/lib/exports.c since this should be asm. */
20 19
21/* Must be 8 bytes in size. */ 20/* Must be 8 bytes in size. */
@@ -188,6 +187,7 @@ int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
188 187
189 /* n != 0 if we get here. Write out any trailing bytes. */ 188 /* n != 0 if we get here. Write out any trailing bytes. */
190 dst1 = (char *)dst8; 189 dst1 = (char *)dst8;
190#ifndef __BIG_ENDIAN__
191 if (n & 4) { 191 if (n & 4) {
192 ST4((uint32_t *)dst1, final); 192 ST4((uint32_t *)dst1, final);
193 dst1 += 4; 193 dst1 += 4;
@@ -202,11 +202,30 @@ int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
202 } 202 }
203 if (n) 203 if (n)
204 ST1((uint8_t *)dst1, final); 204 ST1((uint8_t *)dst1, final);
205#else
206 if (n & 4) {
207 ST4((uint32_t *)dst1, final >> 32);
208 dst1 += 4;
209 }
210 else
211 {
212 final >>= 32;
213 }
214 if (n & 2) {
215 ST2((uint16_t *)dst1, final >> 16);
216 dst1 += 2;
217 }
218 else
219 {
220 final >>= 16;
221 }
222 if (n & 1)
223 ST1((uint8_t *)dst1, final >> 8);
224#endif
205 225
206 return RETVAL; 226 return RETVAL;
207} 227}
208 228
209
210#ifdef USERCOPY_FUNC 229#ifdef USERCOPY_FUNC
211#undef ST1 230#undef ST1
212#undef ST2 231#undef ST2
diff --git a/arch/tile/lib/memcpy_tile64.c b/arch/tile/lib/memcpy_tile64.c
index b2fe15e01075..3bc4b4e40d93 100644
--- a/arch/tile/lib/memcpy_tile64.c
+++ b/arch/tile/lib/memcpy_tile64.c
@@ -160,7 +160,7 @@ retry_source:
160 break; 160 break;
161 if (get_remote_cache_cpu(src_pte) == smp_processor_id()) 161 if (get_remote_cache_cpu(src_pte) == smp_processor_id())
162 break; 162 break;
163 src_page = pfn_to_page(hv_pte_get_pfn(src_pte)); 163 src_page = pfn_to_page(pte_pfn(src_pte));
164 get_page(src_page); 164 get_page(src_page);
165 if (pte_val(src_pte) != pte_val(*src_ptep)) { 165 if (pte_val(src_pte) != pte_val(*src_ptep)) {
166 put_page(src_page); 166 put_page(src_page);
@@ -168,7 +168,7 @@ retry_source:
168 } 168 }
169 if (pte_huge(src_pte)) { 169 if (pte_huge(src_pte)) {
170 /* Adjust the PTE to correspond to a small page */ 170 /* Adjust the PTE to correspond to a small page */
171 int pfn = hv_pte_get_pfn(src_pte); 171 int pfn = pte_pfn(src_pte);
172 pfn += (((unsigned long)source & (HPAGE_SIZE-1)) 172 pfn += (((unsigned long)source & (HPAGE_SIZE-1))
173 >> PAGE_SHIFT); 173 >> PAGE_SHIFT);
174 src_pte = pfn_pte(pfn, src_pte); 174 src_pte = pfn_pte(pfn, src_pte);
@@ -188,7 +188,7 @@ retry_dest:
188 put_page(src_page); 188 put_page(src_page);
189 break; 189 break;
190 } 190 }
191 dst_page = pfn_to_page(hv_pte_get_pfn(dst_pte)); 191 dst_page = pfn_to_page(pte_pfn(dst_pte));
192 if (dst_page == src_page) { 192 if (dst_page == src_page) {
193 /* 193 /*
194 * Source and dest are on the same page; this 194 * Source and dest are on the same page; this
@@ -206,7 +206,7 @@ retry_dest:
206 } 206 }
207 if (pte_huge(dst_pte)) { 207 if (pte_huge(dst_pte)) {
208 /* Adjust the PTE to correspond to a small page */ 208 /* Adjust the PTE to correspond to a small page */
209 int pfn = hv_pte_get_pfn(dst_pte); 209 int pfn = pte_pfn(dst_pte);
210 pfn += (((unsigned long)dest & (HPAGE_SIZE-1)) 210 pfn += (((unsigned long)dest & (HPAGE_SIZE-1))
211 >> PAGE_SHIFT); 211 >> PAGE_SHIFT);
212 dst_pte = pfn_pte(pfn, dst_pte); 212 dst_pte = pfn_pte(pfn, dst_pte);
diff --git a/arch/tile/lib/strchr_64.c b/arch/tile/lib/strchr_64.c
index 617a9273aaa8..f39f9dc422b0 100644
--- a/arch/tile/lib/strchr_64.c
+++ b/arch/tile/lib/strchr_64.c
@@ -15,8 +15,7 @@
15#include <linux/types.h> 15#include <linux/types.h>
16#include <linux/string.h> 16#include <linux/string.h>
17#include <linux/module.h> 17#include <linux/module.h>
18 18#include "string-endian.h"
19#undef strchr
20 19
21char *strchr(const char *s, int c) 20char *strchr(const char *s, int c)
22{ 21{
@@ -33,13 +32,9 @@ char *strchr(const char *s, int c)
33 * match neither zero nor goal (we make sure the high bit of each 32 * match neither zero nor goal (we make sure the high bit of each
34 * byte is 1, and the low 7 bits are all the opposite of the goal 33 * byte is 1, and the low 7 bits are all the opposite of the goal
35 * byte). 34 * byte).
36 *
37 * Note that this shift count expression works because we know shift
38 * counts are taken mod 64.
39 */ 35 */
40 const uint64_t before_mask = (1ULL << (s_int << 3)) - 1; 36 const uint64_t before_mask = MASK(s_int);
41 uint64_t v = (*p | before_mask) ^ 37 uint64_t v = (*p | before_mask) ^ (goal & __insn_v1shrui(before_mask, 1));
42 (goal & __insn_v1shrsi(before_mask, 1));
43 38
44 uint64_t zero_matches, goal_matches; 39 uint64_t zero_matches, goal_matches;
45 while (1) { 40 while (1) {
@@ -55,8 +50,8 @@ char *strchr(const char *s, int c)
55 v = *++p; 50 v = *++p;
56 } 51 }
57 52
58 z = __insn_ctz(zero_matches); 53 z = CFZ(zero_matches);
59 g = __insn_ctz(goal_matches); 54 g = CFZ(goal_matches);
60 55
61 /* If we found c before '\0' we got a match. Note that if c == '\0' 56 /* If we found c before '\0' we got a match. Note that if c == '\0'
62 * then g == z, and we correctly return the address of the '\0' 57 * then g == z, and we correctly return the address of the '\0'
diff --git a/arch/tile/lib/string-endian.h b/arch/tile/lib/string-endian.h
new file mode 100644
index 000000000000..c0eed7ce69c3
--- /dev/null
+++ b/arch/tile/lib/string-endian.h
@@ -0,0 +1,33 @@
1/*
2 * Copyright 2011 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 *
14 * Provide a mask based on the pointer alignment that
15 * sets up non-zero bytes before the beginning of the string.
16 * The MASK expression works because shift counts are taken mod 64.
17 * Also, specify how to count "first" and "last" bits
18 * when the bits have been read as a word.
19 */
20
21#include <asm/byteorder.h>
22
23#ifdef __LITTLE_ENDIAN
24#define MASK(x) (__insn_shl(1ULL, (x << 3)) - 1)
25#define NULMASK(x) ((2ULL << x) - 1)
26#define CFZ(x) __insn_ctz(x)
27#define REVCZ(x) __insn_clz(x)
28#else
29#define MASK(x) (__insn_shl(-2LL, ((-x << 3) - 1)))
30#define NULMASK(x) (-2LL << (63 - x))
31#define CFZ(x) __insn_clz(x)
32#define REVCZ(x) __insn_ctz(x)
33#endif
diff --git a/arch/tile/lib/strlen_64.c b/arch/tile/lib/strlen_64.c
index 1c92d46202a8..9583fc3361fa 100644
--- a/arch/tile/lib/strlen_64.c
+++ b/arch/tile/lib/strlen_64.c
@@ -15,8 +15,7 @@
15#include <linux/types.h> 15#include <linux/types.h>
16#include <linux/string.h> 16#include <linux/string.h>
17#include <linux/module.h> 17#include <linux/module.h>
18 18#include "string-endian.h"
19#undef strlen
20 19
21size_t strlen(const char *s) 20size_t strlen(const char *s)
22{ 21{
@@ -24,15 +23,13 @@ size_t strlen(const char *s)
24 const uintptr_t s_int = (uintptr_t) s; 23 const uintptr_t s_int = (uintptr_t) s;
25 const uint64_t *p = (const uint64_t *)(s_int & -8); 24 const uint64_t *p = (const uint64_t *)(s_int & -8);
26 25
27 /* Read the first word, but force bytes before the string to be nonzero. 26 /* Read and MASK the first word. */
28 * This expression works because we know shift counts are taken mod 64. 27 uint64_t v = *p | MASK(s_int);
29 */
30 uint64_t v = *p | ((1ULL << (s_int << 3)) - 1);
31 28
32 uint64_t bits; 29 uint64_t bits;
33 while ((bits = __insn_v1cmpeqi(v, 0)) == 0) 30 while ((bits = __insn_v1cmpeqi(v, 0)) == 0)
34 v = *++p; 31 v = *++p;
35 32
36 return ((const char *)p) + (__insn_ctz(bits) >> 3) - s; 33 return ((const char *)p) + (CFZ(bits) >> 3) - s;
37} 34}
38EXPORT_SYMBOL(strlen); 35EXPORT_SYMBOL(strlen);
diff --git a/arch/tile/lib/usercopy_32.S b/arch/tile/lib/usercopy_32.S
index 979f76d83746..b62d002af009 100644
--- a/arch/tile/lib/usercopy_32.S
+++ b/arch/tile/lib/usercopy_32.S
@@ -19,82 +19,6 @@
19 19
20/* Access user memory, but use MMU to avoid propagating kernel exceptions. */ 20/* Access user memory, but use MMU to avoid propagating kernel exceptions. */
21 21
22 .pushsection .fixup,"ax"
23
24get_user_fault:
25 { move r0, zero; move r1, zero }
26 { movei r2, -EFAULT; jrp lr }
27 ENDPROC(get_user_fault)
28
29put_user_fault:
30 { movei r0, -EFAULT; jrp lr }
31 ENDPROC(put_user_fault)
32
33 .popsection
34
35/*
36 * __get_user_N functions take a pointer in r0, and return 0 in r2
37 * on success, with the value in r0; or else -EFAULT in r2.
38 */
39#define __get_user_N(bytes, LOAD) \
40 STD_ENTRY(__get_user_##bytes); \
411: { LOAD r0, r0; move r1, zero; move r2, zero }; \
42 jrp lr; \
43 STD_ENDPROC(__get_user_##bytes); \
44 .pushsection __ex_table,"a"; \
45 .word 1b, get_user_fault; \
46 .popsection
47
48__get_user_N(1, lb_u)
49__get_user_N(2, lh_u)
50__get_user_N(4, lw)
51
52/*
53 * __get_user_8 takes a pointer in r0, and returns 0 in r2
54 * on success, with the value in r0/r1; or else -EFAULT in r2.
55 */
56 STD_ENTRY(__get_user_8);
571: { lw r0, r0; addi r1, r0, 4 };
582: { lw r1, r1; move r2, zero };
59 jrp lr;
60 STD_ENDPROC(__get_user_8);
61 .pushsection __ex_table,"a";
62 .word 1b, get_user_fault;
63 .word 2b, get_user_fault;
64 .popsection
65
66/*
67 * __put_user_N functions take a value in r0 and a pointer in r1,
68 * and return 0 in r0 on success or -EFAULT on failure.
69 */
70#define __put_user_N(bytes, STORE) \
71 STD_ENTRY(__put_user_##bytes); \
721: { STORE r1, r0; move r0, zero }; \
73 jrp lr; \
74 STD_ENDPROC(__put_user_##bytes); \
75 .pushsection __ex_table,"a"; \
76 .word 1b, put_user_fault; \
77 .popsection
78
79__put_user_N(1, sb)
80__put_user_N(2, sh)
81__put_user_N(4, sw)
82
83/*
84 * __put_user_8 takes a value in r0/r1 and a pointer in r2,
85 * and returns 0 in r0 on success or -EFAULT on failure.
86 */
87STD_ENTRY(__put_user_8)
881: { sw r2, r0; addi r2, r2, 4 }
892: { sw r2, r1; move r0, zero }
90 jrp lr
91 STD_ENDPROC(__put_user_8)
92 .pushsection __ex_table,"a"
93 .word 1b, put_user_fault
94 .word 2b, put_user_fault
95 .popsection
96
97
98/* 22/*
99 * strnlen_user_asm takes the pointer in r0, and the length bound in r1. 23 * strnlen_user_asm takes the pointer in r0, and the length bound in r1.
100 * It returns the length, including the terminating NUL, or zero on exception. 24 * It returns the length, including the terminating NUL, or zero on exception.
diff --git a/arch/tile/lib/usercopy_64.S b/arch/tile/lib/usercopy_64.S
index 2ff44f87b78e..adb2dbbc70cd 100644
--- a/arch/tile/lib/usercopy_64.S
+++ b/arch/tile/lib/usercopy_64.S
@@ -19,55 +19,6 @@
19 19
20/* Access user memory, but use MMU to avoid propagating kernel exceptions. */ 20/* Access user memory, but use MMU to avoid propagating kernel exceptions. */
21 21
22 .pushsection .fixup,"ax"
23
24get_user_fault:
25 { movei r1, -EFAULT; move r0, zero }
26 jrp lr
27 ENDPROC(get_user_fault)
28
29put_user_fault:
30 { movei r0, -EFAULT; jrp lr }
31 ENDPROC(put_user_fault)
32
33 .popsection
34
35/*
36 * __get_user_N functions take a pointer in r0, and return 0 in r1
37 * on success, with the value in r0; or else -EFAULT in r1.
38 */
39#define __get_user_N(bytes, LOAD) \
40 STD_ENTRY(__get_user_##bytes); \
411: { LOAD r0, r0; move r1, zero }; \
42 jrp lr; \
43 STD_ENDPROC(__get_user_##bytes); \
44 .pushsection __ex_table,"a"; \
45 .quad 1b, get_user_fault; \
46 .popsection
47
48__get_user_N(1, ld1u)
49__get_user_N(2, ld2u)
50__get_user_N(4, ld4u)
51__get_user_N(8, ld)
52
53/*
54 * __put_user_N functions take a value in r0 and a pointer in r1,
55 * and return 0 in r0 on success or -EFAULT on failure.
56 */
57#define __put_user_N(bytes, STORE) \
58 STD_ENTRY(__put_user_##bytes); \
591: { STORE r1, r0; move r0, zero }; \
60 jrp lr; \
61 STD_ENDPROC(__put_user_##bytes); \
62 .pushsection __ex_table,"a"; \
63 .quad 1b, put_user_fault; \
64 .popsection
65
66__put_user_N(1, st1)
67__put_user_N(2, st2)
68__put_user_N(4, st4)
69__put_user_N(8, st)
70
71/* 22/*
72 * strnlen_user_asm takes the pointer in r0, and the length bound in r1. 23 * strnlen_user_asm takes the pointer in r0, and the length bound in r1.
73 * It returns the length, including the terminating NUL, or zero on exception. 24 * It returns the length, including the terminating NUL, or zero on exception.