Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 2011
4 * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
5 */
6#include <linux/hugetlb.h>
7#include <linux/mm.h>
8#include <asm/cacheflush.h>
9#include <asm/facility.h>
10#include <asm/pgalloc.h>
11#include <asm/kfence.h>
12#include <asm/page.h>
13#include <asm/set_memory.h>
14
15static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
16{
17 asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],1,0"
18 : [addr] "+a" (addr) : [skey] "d" (skey));
19 return addr;
20}
21
22void __storage_key_init_range(unsigned long start, unsigned long end)
23{
24 unsigned long boundary, size;
25
26 while (start < end) {
27 if (MACHINE_HAS_EDAT1) {
28 /* set storage keys for a 1MB frame */
29 size = 1UL << 20;
30 boundary = (start + size) & ~(size - 1);
31 if (boundary <= end) {
32 do {
33 start = sske_frame(start, PAGE_DEFAULT_KEY);
34 } while (start < boundary);
35 continue;
36 }
37 }
38 page_set_storage_key(start, PAGE_DEFAULT_KEY, 1);
39 start += PAGE_SIZE;
40 }
41}
42
43#ifdef CONFIG_PROC_FS
44atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
45
46void arch_report_meminfo(struct seq_file *m)
47{
48 seq_printf(m, "DirectMap4k: %8lu kB\n",
49 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2);
50 seq_printf(m, "DirectMap1M: %8lu kB\n",
51 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10);
52 seq_printf(m, "DirectMap2G: %8lu kB\n",
53 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21);
54}
55#endif /* CONFIG_PROC_FS */
56
57static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
58 unsigned long dtt)
59{
60 unsigned long *table, mask;
61
62 mask = 0;
63 if (MACHINE_HAS_EDAT2) {
64 switch (dtt) {
65 case CRDTE_DTT_REGION3:
66 mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
67 break;
68 case CRDTE_DTT_SEGMENT:
69 mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
70 break;
71 case CRDTE_DTT_PAGE:
72 mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1);
73 break;
74 }
75 table = (unsigned long *)((unsigned long)old & mask);
76 crdte(*old, new, table, dtt, addr, S390_lowcore.kernel_asce);
77 } else if (MACHINE_HAS_IDTE) {
78 cspg(old, *old, new);
79 } else {
80 csp((unsigned int *)old + 1, *old, new);
81 }
82}
83
84static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
85 unsigned long flags)
86{
87 pte_t *ptep, new;
88
89 if (flags == SET_MEMORY_4K)
90 return 0;
91 ptep = pte_offset_kernel(pmdp, addr);
92 do {
93 new = *ptep;
94 if (pte_none(new))
95 return -EINVAL;
96 if (flags & SET_MEMORY_RO)
97 new = pte_wrprotect(new);
98 else if (flags & SET_MEMORY_RW)
99 new = pte_mkwrite(pte_mkdirty(new));
100 if (flags & SET_MEMORY_NX)
101 new = set_pte_bit(new, __pgprot(_PAGE_NOEXEC));
102 else if (flags & SET_MEMORY_X)
103 new = clear_pte_bit(new, __pgprot(_PAGE_NOEXEC));
104 pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
105 ptep++;
106 addr += PAGE_SIZE;
107 cond_resched();
108 } while (addr < end);
109 return 0;
110}
111
112static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
113{
114 unsigned long pte_addr, prot;
115 pte_t *pt_dir, *ptep;
116 pmd_t new;
117 int i, ro, nx;
118
119 pt_dir = vmem_pte_alloc();
120 if (!pt_dir)
121 return -ENOMEM;
122 pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT;
123 ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT);
124 nx = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_NOEXEC);
125 prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
126 if (!nx)
127 prot &= ~_PAGE_NOEXEC;
128 ptep = pt_dir;
129 for (i = 0; i < PTRS_PER_PTE; i++) {
130 set_pte(ptep, __pte(pte_addr | prot));
131 pte_addr += PAGE_SIZE;
132 ptep++;
133 }
134 new = __pmd(__pa(pt_dir) | _SEGMENT_ENTRY);
135 pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
136 update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE);
137 update_page_count(PG_DIRECT_MAP_1M, -1);
138 return 0;
139}
140
141static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
142 unsigned long flags)
143{
144 pmd_t new = *pmdp;
145
146 if (flags & SET_MEMORY_RO)
147 new = pmd_wrprotect(new);
148 else if (flags & SET_MEMORY_RW)
149 new = pmd_mkwrite(pmd_mkdirty(new));
150 if (flags & SET_MEMORY_NX)
151 new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
152 else if (flags & SET_MEMORY_X)
153 new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
154 pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
155}
156
157static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
158 unsigned long flags)
159{
160 unsigned long next;
161 int need_split;
162 pmd_t *pmdp;
163 int rc = 0;
164
165 pmdp = pmd_offset(pudp, addr);
166 do {
167 if (pmd_none(*pmdp))
168 return -EINVAL;
169 next = pmd_addr_end(addr, end);
170 if (pmd_large(*pmdp)) {
171 need_split = !!(flags & SET_MEMORY_4K);
172 need_split |= !!(addr & ~PMD_MASK);
173 need_split |= !!(addr + PMD_SIZE > next);
174 if (need_split) {
175 rc = split_pmd_page(pmdp, addr);
176 if (rc)
177 return rc;
178 continue;
179 }
180 modify_pmd_page(pmdp, addr, flags);
181 } else {
182 rc = walk_pte_level(pmdp, addr, next, flags);
183 if (rc)
184 return rc;
185 }
186 pmdp++;
187 addr = next;
188 cond_resched();
189 } while (addr < end);
190 return rc;
191}
192
193static int split_pud_page(pud_t *pudp, unsigned long addr)
194{
195 unsigned long pmd_addr, prot;
196 pmd_t *pm_dir, *pmdp;
197 pud_t new;
198 int i, ro, nx;
199
200 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
201 if (!pm_dir)
202 return -ENOMEM;
203 pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
204 ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
205 nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC);
206 prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
207 if (!nx)
208 prot &= ~_SEGMENT_ENTRY_NOEXEC;
209 pmdp = pm_dir;
210 for (i = 0; i < PTRS_PER_PMD; i++) {
211 set_pmd(pmdp, __pmd(pmd_addr | prot));
212 pmd_addr += PMD_SIZE;
213 pmdp++;
214 }
215 new = __pud(__pa(pm_dir) | _REGION3_ENTRY);
216 pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
217 update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD);
218 update_page_count(PG_DIRECT_MAP_2G, -1);
219 return 0;
220}
221
222static void modify_pud_page(pud_t *pudp, unsigned long addr,
223 unsigned long flags)
224{
225 pud_t new = *pudp;
226
227 if (flags & SET_MEMORY_RO)
228 new = pud_wrprotect(new);
229 else if (flags & SET_MEMORY_RW)
230 new = pud_mkwrite(pud_mkdirty(new));
231 if (flags & SET_MEMORY_NX)
232 new = set_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
233 else if (flags & SET_MEMORY_X)
234 new = clear_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
235 pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
236}
237
238static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end,
239 unsigned long flags)
240{
241 unsigned long next;
242 int need_split;
243 pud_t *pudp;
244 int rc = 0;
245
246 pudp = pud_offset(p4d, addr);
247 do {
248 if (pud_none(*pudp))
249 return -EINVAL;
250 next = pud_addr_end(addr, end);
251 if (pud_large(*pudp)) {
252 need_split = !!(flags & SET_MEMORY_4K);
253 need_split |= !!(addr & ~PUD_MASK);
254 need_split |= !!(addr + PUD_SIZE > next);
255 if (need_split) {
256 rc = split_pud_page(pudp, addr);
257 if (rc)
258 break;
259 continue;
260 }
261 modify_pud_page(pudp, addr, flags);
262 } else {
263 rc = walk_pmd_level(pudp, addr, next, flags);
264 }
265 pudp++;
266 addr = next;
267 cond_resched();
268 } while (addr < end && !rc);
269 return rc;
270}
271
272static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end,
273 unsigned long flags)
274{
275 unsigned long next;
276 p4d_t *p4dp;
277 int rc = 0;
278
279 p4dp = p4d_offset(pgd, addr);
280 do {
281 if (p4d_none(*p4dp))
282 return -EINVAL;
283 next = p4d_addr_end(addr, end);
284 rc = walk_pud_level(p4dp, addr, next, flags);
285 p4dp++;
286 addr = next;
287 cond_resched();
288 } while (addr < end && !rc);
289 return rc;
290}
291
292DEFINE_MUTEX(cpa_mutex);
293
294static int change_page_attr(unsigned long addr, unsigned long end,
295 unsigned long flags)
296{
297 unsigned long next;
298 int rc = -EINVAL;
299 pgd_t *pgdp;
300
301 if (addr == end)
302 return 0;
303 if (end >= MODULES_END)
304 return -EINVAL;
305 mutex_lock(&cpa_mutex);
306 pgdp = pgd_offset_k(addr);
307 do {
308 if (pgd_none(*pgdp))
309 break;
310 next = pgd_addr_end(addr, end);
311 rc = walk_p4d_level(pgdp, addr, next, flags);
312 if (rc)
313 break;
314 cond_resched();
315 } while (pgdp++, addr = next, addr < end && !rc);
316 mutex_unlock(&cpa_mutex);
317 return rc;
318}
319
320int __set_memory(unsigned long addr, int numpages, unsigned long flags)
321{
322 if (!MACHINE_HAS_NX)
323 flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
324 if (!flags)
325 return 0;
326 addr &= PAGE_MASK;
327 return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags);
328}
329
330#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE)
331
332static void ipte_range(pte_t *pte, unsigned long address, int nr)
333{
334 int i;
335
336 if (test_facility(13)) {
337 __ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL);
338 return;
339 }
340 for (i = 0; i < nr; i++) {
341 __ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL);
342 address += PAGE_SIZE;
343 pte++;
344 }
345}
346
347void __kernel_map_pages(struct page *page, int numpages, int enable)
348{
349 unsigned long address;
350 pte_t *ptep, pte;
351 int nr, i, j;
352
353 for (i = 0; i < numpages;) {
354 address = (unsigned long)page_to_virt(page + i);
355 ptep = virt_to_kpte(address);
356 nr = (unsigned long)ptep >> ilog2(sizeof(long));
357 nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
358 nr = min(numpages - i, nr);
359 if (enable) {
360 for (j = 0; j < nr; j++) {
361 pte = clear_pte_bit(*ptep, __pgprot(_PAGE_INVALID));
362 set_pte(ptep, pte);
363 address += PAGE_SIZE;
364 ptep++;
365 }
366 } else {
367 ipte_range(ptep, address, nr);
368 }
369 i += nr;
370 }
371}
372
373#endif /* CONFIG_DEBUG_PAGEALLOC */
1/*
2 * Copyright IBM Corp. 2011
3 * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
4 */
5#include <linux/hugetlb.h>
6#include <linux/module.h>
7#include <linux/mm.h>
8#include <asm/cacheflush.h>
9#include <asm/facility.h>
10#include <asm/pgtable.h>
11#include <asm/page.h>
12
13#if PAGE_DEFAULT_KEY
14static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
15{
16 asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],9,0"
17 : [addr] "+a" (addr) : [skey] "d" (skey));
18 return addr;
19}
20
21void __storage_key_init_range(unsigned long start, unsigned long end)
22{
23 unsigned long boundary, size;
24
25 while (start < end) {
26 if (MACHINE_HAS_EDAT1) {
27 /* set storage keys for a 1MB frame */
28 size = 1UL << 20;
29 boundary = (start + size) & ~(size - 1);
30 if (boundary <= end) {
31 do {
32 start = sske_frame(start, PAGE_DEFAULT_KEY);
33 } while (start < boundary);
34 continue;
35 }
36 }
37 page_set_storage_key(start, PAGE_DEFAULT_KEY, 0);
38 start += PAGE_SIZE;
39 }
40}
41#endif
42
43static pte_t *walk_page_table(unsigned long addr)
44{
45 pgd_t *pgdp;
46 pud_t *pudp;
47 pmd_t *pmdp;
48 pte_t *ptep;
49
50 pgdp = pgd_offset_k(addr);
51 if (pgd_none(*pgdp))
52 return NULL;
53 pudp = pud_offset(pgdp, addr);
54 if (pud_none(*pudp) || pud_large(*pudp))
55 return NULL;
56 pmdp = pmd_offset(pudp, addr);
57 if (pmd_none(*pmdp) || pmd_large(*pmdp))
58 return NULL;
59 ptep = pte_offset_kernel(pmdp, addr);
60 if (pte_none(*ptep))
61 return NULL;
62 return ptep;
63}
64
65static void change_page_attr(unsigned long addr, int numpages,
66 pte_t (*set) (pte_t))
67{
68 pte_t *ptep;
69 int i;
70
71 for (i = 0; i < numpages; i++) {
72 ptep = walk_page_table(addr);
73 if (WARN_ON_ONCE(!ptep))
74 break;
75 *ptep = set(*ptep);
76 addr += PAGE_SIZE;
77 }
78 __tlb_flush_kernel();
79}
80
81int set_memory_ro(unsigned long addr, int numpages)
82{
83 change_page_attr(addr, numpages, pte_wrprotect);
84 return 0;
85}
86
87int set_memory_rw(unsigned long addr, int numpages)
88{
89 change_page_attr(addr, numpages, pte_mkwrite);
90 return 0;
91}
92
93/* not possible */
94int set_memory_nx(unsigned long addr, int numpages)
95{
96 return 0;
97}
98
99int set_memory_x(unsigned long addr, int numpages)
100{
101 return 0;
102}
103
104#ifdef CONFIG_DEBUG_PAGEALLOC
105
106static void ipte_range(pte_t *pte, unsigned long address, int nr)
107{
108 int i;
109
110 if (test_facility(13)) {
111 __ptep_ipte_range(address, nr - 1, pte);
112 return;
113 }
114 for (i = 0; i < nr; i++) {
115 __ptep_ipte(address, pte);
116 address += PAGE_SIZE;
117 pte++;
118 }
119}
120
121void __kernel_map_pages(struct page *page, int numpages, int enable)
122{
123 unsigned long address;
124 int nr, i, j;
125 pgd_t *pgd;
126 pud_t *pud;
127 pmd_t *pmd;
128 pte_t *pte;
129
130 for (i = 0; i < numpages;) {
131 address = page_to_phys(page + i);
132 pgd = pgd_offset_k(address);
133 pud = pud_offset(pgd, address);
134 pmd = pmd_offset(pud, address);
135 pte = pte_offset_kernel(pmd, address);
136 nr = (unsigned long)pte >> ilog2(sizeof(long));
137 nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
138 nr = min(numpages - i, nr);
139 if (enable) {
140 for (j = 0; j < nr; j++) {
141 pte_val(*pte) = __pa(address);
142 address += PAGE_SIZE;
143 pte++;
144 }
145 } else {
146 ipte_range(pte, address, nr);
147 }
148 i += nr;
149 }
150}
151
152#ifdef CONFIG_HIBERNATION
153bool kernel_page_present(struct page *page)
154{
155 unsigned long addr;
156 int cc;
157
158 addr = page_to_phys(page);
159 asm volatile(
160 " lra %1,0(%1)\n"
161 " ipm %0\n"
162 " srl %0,28"
163 : "=d" (cc), "+a" (addr) : : "cc");
164 return cc == 0;
165}
166#endif /* CONFIG_HIBERNATION */
167
168#endif /* CONFIG_DEBUG_PAGEALLOC */