This source file includes following definitions.
- setup_no_alternatives
- apply_alternatives
- apply_alternatives_all
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8 #include <asm/processor.h>
9 #include <asm/sections.h>
10 #include <asm/alternative.h>
11
12 #include <linux/module.h>
13
14 static int no_alternatives;
15 static int __init setup_no_alternatives(char *str)
16 {
17 no_alternatives = 1;
18 return 1;
19 }
20 __setup("no-alternatives", setup_no_alternatives);
21
22 void __init_or_module apply_alternatives(struct alt_instr *start,
23 struct alt_instr *end, const char *module_name)
24 {
25 struct alt_instr *entry;
26 int index = 0, applied = 0;
27 int num_cpus = num_online_cpus();
28
29 for (entry = start; entry < end; entry++, index++) {
30
31 u32 *from, cond, replacement;
32 s32 len;
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34 from = (u32 *)((ulong)&entry->orig_offset + entry->orig_offset);
35 len = entry->len;
36 cond = entry->cond;
37 replacement = entry->replacement;
38
39 WARN_ON(!cond);
40
41 if (cond != ALT_COND_ALWAYS && no_alternatives)
42 continue;
43
44 pr_debug("Check %d: Cond 0x%x, Replace %02d instructions @ 0x%px with 0x%08x\n",
45 index, cond, len, from, replacement);
46
47 if ((cond & ALT_COND_NO_SMP) && (num_cpus != 1))
48 continue;
49 if ((cond & ALT_COND_NO_DCACHE) && (cache_info.dc_size != 0))
50 continue;
51 if ((cond & ALT_COND_NO_ICACHE) && (cache_info.ic_size != 0))
52 continue;
53 if ((cond & ALT_COND_RUN_ON_QEMU) && !running_on_qemu)
54 continue;
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60
61 if ((cond & ALT_COND_NO_IOC_FDC) &&
62 ((boot_cpu_data.cpu_type <= pcxw_) ||
63 (boot_cpu_data.pdc.capabilities & PDC_MODEL_IOPDIR_FDC)))
64 continue;
65
66
67 if (replacement == INSN_PxTLB) {
68 replacement = *from;
69 if (boot_cpu_data.cpu_type >= pcxu)
70 replacement |= (1 << 10);
71 }
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75
76
77 if (replacement == INSN_NOP && len > 1)
78 replacement = 0xe8000002 + (len-2)*8;
79
80 pr_debug("ALTERNATIVE %3d: Cond %2x, Replace %2d instructions to 0x%08x @ 0x%px (%pS)\n",
81 index, cond, len, replacement, from, from);
82
83 if (len < 0) {
84
85 u32 *source;
86 len = -len;
87 source = (u32 *)((ulong)&entry->replacement + entry->replacement);
88 memcpy(from, source, 4 * len);
89 } else {
90
91 *from = replacement;
92 }
93 applied++;
94 }
95
96 pr_info("%s%salternatives: applied %d out of %d patches\n",
97 module_name ? : "", module_name ? " " : "",
98 applied, index);
99 }
100
101
102 void __init apply_alternatives_all(void)
103 {
104 set_kernel_text_rw(1);
105
106 apply_alternatives((struct alt_instr *) &__alt_instructions,
107 (struct alt_instr *) &__alt_instructions_end, NULL);
108
109 set_kernel_text_rw(0);
110 }