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10#include <linux/kernel.h>
11#include <linux/errno.h>
12#include <linux/types.h>
13#include <linux/mm.h>
14#include <linux/memblock.h>
15#include <linux/gfp.h>
16#include <linux/init.h>
17#include <asm/facility.h>
18#include <asm/page-states.h>
19
20static int cmma_flag = 1;
21
22static int __init cmma(char *str)
23{
24 bool enabled;
25
26 if (!kstrtobool(str, &enabled))
27 cmma_flag = enabled;
28 return 1;
29}
30__setup("cmma=", cmma);
31
32static inline int cmma_test_essa(void)
33{
34 unsigned long tmp = 0;
35 int rc = -EOPNOTSUPP;
36
37
38 asm volatile(
39 " .insn rrf,0xb9ab0000,%[tmp],%[tmp],%[cmd],0\n"
40 "0: la %[rc],0\n"
41 "1:\n"
42 EX_TABLE(0b,1b)
43 : [rc] "+&d" (rc), [tmp] "+&d" (tmp)
44 : [cmd] "i" (ESSA_GET_STATE));
45 return rc;
46}
47
48void __init cmma_init(void)
49{
50 if (!cmma_flag)
51 return;
52 if (cmma_test_essa()) {
53 cmma_flag = 0;
54 return;
55 }
56 if (test_facility(147))
57 cmma_flag = 2;
58}
59
60static inline unsigned char get_page_state(struct page *page)
61{
62 unsigned char state;
63
64 asm volatile(" .insn rrf,0xb9ab0000,%0,%1,%2,0"
65 : "=&d" (state)
66 : "a" (page_to_phys(page)),
67 "i" (ESSA_GET_STATE));
68 return state & 0x3f;
69}
70
71static inline void set_page_unused(struct page *page, int order)
72{
73 int i, rc;
74
75 for (i = 0; i < (1 << order); i++)
76 asm volatile(".insn rrf,0xb9ab0000,%0,%1,%2,0"
77 : "=&d" (rc)
78 : "a" (page_to_phys(page + i)),
79 "i" (ESSA_SET_UNUSED));
80}
81
82static inline void set_page_stable_dat(struct page *page, int order)
83{
84 int i, rc;
85
86 for (i = 0; i < (1 << order); i++)
87 asm volatile(".insn rrf,0xb9ab0000,%0,%1,%2,0"
88 : "=&d" (rc)
89 : "a" (page_to_phys(page + i)),
90 "i" (ESSA_SET_STABLE));
91}
92
93static inline void set_page_stable_nodat(struct page *page, int order)
94{
95 int i, rc;
96
97 for (i = 0; i < (1 << order); i++)
98 asm volatile(".insn rrf,0xb9ab0000,%0,%1,%2,0"
99 : "=&d" (rc)
100 : "a" (page_to_phys(page + i)),
101 "i" (ESSA_SET_STABLE_NODAT));
102}
103
104static void mark_kernel_pmd(pud_t *pud, unsigned long addr, unsigned long end)
105{
106 unsigned long next;
107 struct page *page;
108 pmd_t *pmd;
109
110 pmd = pmd_offset(pud, addr);
111 do {
112 next = pmd_addr_end(addr, end);
113 if (pmd_none(*pmd) || pmd_large(*pmd))
114 continue;
115 page = phys_to_page(pmd_val(*pmd));
116 set_bit(PG_arch_1, &page->flags);
117 } while (pmd++, addr = next, addr != end);
118}
119
120static void mark_kernel_pud(p4d_t *p4d, unsigned long addr, unsigned long end)
121{
122 unsigned long next;
123 struct page *page;
124 pud_t *pud;
125 int i;
126
127 pud = pud_offset(p4d, addr);
128 do {
129 next = pud_addr_end(addr, end);
130 if (pud_none(*pud) || pud_large(*pud))
131 continue;
132 if (!pud_folded(*pud)) {
133 page = phys_to_page(pud_val(*pud));
134 for (i = 0; i < 3; i++)
135 set_bit(PG_arch_1, &page[i].flags);
136 }
137 mark_kernel_pmd(pud, addr, next);
138 } while (pud++, addr = next, addr != end);
139}
140
141static void mark_kernel_p4d(pgd_t *pgd, unsigned long addr, unsigned long end)
142{
143 unsigned long next;
144 struct page *page;
145 p4d_t *p4d;
146 int i;
147
148 p4d = p4d_offset(pgd, addr);
149 do {
150 next = p4d_addr_end(addr, end);
151 if (p4d_none(*p4d))
152 continue;
153 if (!p4d_folded(*p4d)) {
154 page = phys_to_page(p4d_val(*p4d));
155 for (i = 0; i < 3; i++)
156 set_bit(PG_arch_1, &page[i].flags);
157 }
158 mark_kernel_pud(p4d, addr, next);
159 } while (p4d++, addr = next, addr != end);
160}
161
162static void mark_kernel_pgd(void)
163{
164 unsigned long addr, next;
165 struct page *page;
166 pgd_t *pgd;
167 int i;
168
169 addr = 0;
170 pgd = pgd_offset_k(addr);
171 do {
172 next = pgd_addr_end(addr, MODULES_END);
173 if (pgd_none(*pgd))
174 continue;
175 if (!pgd_folded(*pgd)) {
176 page = phys_to_page(pgd_val(*pgd));
177 for (i = 0; i < 3; i++)
178 set_bit(PG_arch_1, &page[i].flags);
179 }
180 mark_kernel_p4d(pgd, addr, next);
181 } while (pgd++, addr = next, addr != MODULES_END);
182}
183
184void __init cmma_init_nodat(void)
185{
186 struct page *page;
187 unsigned long start, end, ix;
188 int i;
189
190 if (cmma_flag < 2)
191 return;
192
193 mark_kernel_pgd();
194
195
196 for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, NULL) {
197 page = pfn_to_page(start);
198 for (ix = start; ix < end; ix++, page++) {
199 if (__test_and_clear_bit(PG_arch_1, &page->flags))
200 continue;
201 if (!list_empty(&page->lru))
202 continue;
203 set_page_stable_nodat(page, 0);
204 }
205 }
206}
207
208void arch_free_page(struct page *page, int order)
209{
210 if (!cmma_flag)
211 return;
212 set_page_unused(page, order);
213}
214
215void arch_alloc_page(struct page *page, int order)
216{
217 if (!cmma_flag)
218 return;
219 if (cmma_flag < 2)
220 set_page_stable_dat(page, order);
221 else
222 set_page_stable_nodat(page, order);
223}
224
225void arch_set_page_dat(struct page *page, int order)
226{
227 if (!cmma_flag)
228 return;
229 set_page_stable_dat(page, order);
230}
231
