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11#include <linux/uaccess.h>
12#include <linux/kernel.h>
13#include <linux/types.h>
14#include <linux/errno.h>
15#include <linux/gfp.h>
16#include <linux/cpu.h>
17#include <asm/ctl_reg.h>
18#include <asm/io.h>
19
20static notrace long s390_kernel_write_odd(void *dst, const void *src, size_t size)
21{
22 unsigned long aligned, offset, count;
23 char tmp[8];
24
25 aligned = (unsigned long) dst & ~7UL;
26 offset = (unsigned long) dst & 7UL;
27 size = min(8UL - offset, size);
28 count = size - 1;
29 asm volatile(
30 " bras 1,0f\n"
31 " mvc 0(1,%4),0(%5)\n"
32 "0: mvc 0(8,%3),0(%0)\n"
33 " ex %1,0(1)\n"
34 " lg %1,0(%3)\n"
35 " lra %0,0(%0)\n"
36 " sturg %1,%0\n"
37 : "+&a" (aligned), "+&a" (count), "=m" (tmp)
38 : "a" (&tmp), "a" (&tmp[offset]), "a" (src)
39 : "cc", "memory", "1");
40 return size;
41}
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58
59void notrace s390_kernel_write(void *dst, const void *src, size_t size)
60{
61 long copied;
62
63 while (size) {
64 copied = s390_kernel_write_odd(dst, src, size);
65 dst += copied;
66 src += copied;
67 size -= copied;
68 }
69}
70
71static int __memcpy_real(void *dest, void *src, size_t count)
72{
73 register unsigned long _dest asm("2") = (unsigned long) dest;
74 register unsigned long _len1 asm("3") = (unsigned long) count;
75 register unsigned long _src asm("4") = (unsigned long) src;
76 register unsigned long _len2 asm("5") = (unsigned long) count;
77 int rc = -EFAULT;
78
79 asm volatile (
80 "0: mvcle %1,%2,0x0\n"
81 "1: jo 0b\n"
82 " lhi %0,0x0\n"
83 "2:\n"
84 EX_TABLE(1b,2b)
85 : "+d" (rc), "+d" (_dest), "+d" (_src), "+d" (_len1),
86 "+d" (_len2), "=m" (*((long *) dest))
87 : "m" (*((long *) src))
88 : "cc", "memory");
89 return rc;
90}
91
92
93
94
95int memcpy_real(void *dest, void *src, size_t count)
96{
97 int irqs_disabled, rc;
98 unsigned long flags;
99
100 if (!count)
101 return 0;
102 flags = __arch_local_irq_stnsm(0xf8UL);
103 irqs_disabled = arch_irqs_disabled_flags(flags);
104 if (!irqs_disabled)
105 trace_hardirqs_off();
106 rc = __memcpy_real(dest, src, count);
107 if (!irqs_disabled)
108 trace_hardirqs_on();
109 __arch_local_irq_ssm(flags);
110 return rc;
111}
112
113
114
115
116void memcpy_absolute(void *dest, void *src, size_t count)
117{
118 unsigned long cr0, flags, prefix;
119
120 flags = arch_local_irq_save();
121 __ctl_store(cr0, 0, 0);
122 __ctl_clear_bit(0, 28);
123 prefix = store_prefix();
124 if (prefix) {
125 local_mcck_disable();
126 set_prefix(0);
127 memcpy(dest, src, count);
128 set_prefix(prefix);
129 local_mcck_enable();
130 } else {
131 memcpy(dest, src, count);
132 }
133 __ctl_load(cr0, 0, 0);
134 arch_local_irq_restore(flags);
135}
136
137
138
139
140int copy_to_user_real(void __user *dest, void *src, unsigned long count)
141{
142 int offs = 0, size, rc;
143 char *buf;
144
145 buf = (char *) __get_free_page(GFP_KERNEL);
146 if (!buf)
147 return -ENOMEM;
148 rc = -EFAULT;
149 while (offs < count) {
150 size = min(PAGE_SIZE, count - offs);
151 if (memcpy_real(buf, src + offs, size))
152 goto out;
153 if (copy_to_user(dest + offs, buf, size))
154 goto out;
155 offs += size;
156 }
157 rc = 0;
158out:
159 free_page((unsigned long) buf);
160 return rc;
161}
162
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164
165
166static int is_swapped(unsigned long addr)
167{
168 unsigned long lc;
169 int cpu;
170
171 if (addr < sizeof(struct lowcore))
172 return 1;
173 for_each_online_cpu(cpu) {
174 lc = (unsigned long) lowcore_ptr[cpu];
175 if (addr > lc + sizeof(struct lowcore) - 1 || addr < lc)
176 continue;
177 return 1;
178 }
179 return 0;
180}
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187
188void *xlate_dev_mem_ptr(phys_addr_t addr)
189{
190 void *bounce = (void *) addr;
191 unsigned long size;
192
193 get_online_cpus();
194 preempt_disable();
195 if (is_swapped(addr)) {
196 size = PAGE_SIZE - (addr & ~PAGE_MASK);
197 bounce = (void *) __get_free_page(GFP_ATOMIC);
198 if (bounce)
199 memcpy_absolute(bounce, (void *) addr, size);
200 }
201 preempt_enable();
202 put_online_cpus();
203 return bounce;
204}
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208
209void unxlate_dev_mem_ptr(phys_addr_t addr, void *buf)
210{
211 if ((void *) addr != buf)
212 free_page((unsigned long) buf);
213}
214