1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright IBM Corp. 2011
4 * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
6 #include <linux/hugetlb.h>
8 #include <asm/cacheflush.h>
9 #include <asm/facility.h>
10 #include <asm/pgalloc.h>
11 #include <asm/kfence.h>
13 #include <asm/set_memory.h>
15 static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
17 asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],1,0"
18 : [addr] "+a" (addr) : [skey] "d" (skey));
22 void __storage_key_init_range(unsigned long start, unsigned long end)
24 unsigned long boundary, size;
27 if (MACHINE_HAS_EDAT1) {
28 /* set storage keys for a 1MB frame */
30 boundary = (start + size) & ~(size - 1);
31 if (boundary <= end) {
33 start = sske_frame(start, PAGE_DEFAULT_KEY);
34 } while (start < boundary);
38 page_set_storage_key(start, PAGE_DEFAULT_KEY, 1);
44 atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
46 void arch_report_meminfo(struct seq_file *m)
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);
55 #endif /* CONFIG_PROC_FS */
57 static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
60 unsigned long *table, mask;
63 if (MACHINE_HAS_EDAT2) {
65 case CRDTE_DTT_REGION3:
66 mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
68 case CRDTE_DTT_SEGMENT:
69 mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
72 mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1);
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) {
80 csp((unsigned int *)old + 1, *old, new);
84 static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
89 if (flags == SET_MEMORY_4K)
91 ptep = pte_offset_kernel(pmdp, addr);
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);
108 } while (addr < end);
112 static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
114 unsigned long pte_addr, prot;
115 pte_t *pt_dir, *ptep;
119 pt_dir = vmem_pte_alloc();
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);
127 prot &= ~_PAGE_NOEXEC;
129 for (i = 0; i < PTRS_PER_PTE; i++) {
130 set_pte(ptep, __pte(pte_addr | prot));
131 pte_addr += PAGE_SIZE;
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);
141 static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
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);
157 static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
165 pmdp = pmd_offset(pudp, addr);
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);
175 rc = split_pmd_page(pmdp, addr);
180 modify_pmd_page(pmdp, addr, flags);
182 rc = walk_pte_level(pmdp, addr, next, flags);
189 } while (addr < end);
193 static int split_pud_page(pud_t *pudp, unsigned long addr)
195 unsigned long pmd_addr, prot;
196 pmd_t *pm_dir, *pmdp;
200 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
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);
208 prot &= ~_SEGMENT_ENTRY_NOEXEC;
210 for (i = 0; i < PTRS_PER_PMD; i++) {
211 set_pmd(pmdp, __pmd(pmd_addr | prot));
212 pmd_addr += PMD_SIZE;
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);
222 static void modify_pud_page(pud_t *pudp, unsigned long addr,
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);
238 static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end,
246 pudp = pud_offset(p4d, addr);
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);
256 rc = split_pud_page(pudp, addr);
261 modify_pud_page(pudp, addr, flags);
263 rc = walk_pmd_level(pudp, addr, next, flags);
268 } while (addr < end && !rc);
272 static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end,
279 p4dp = p4d_offset(pgd, addr);
283 next = p4d_addr_end(addr, end);
284 rc = walk_pud_level(p4dp, addr, next, flags);
288 } while (addr < end && !rc);
292 DEFINE_MUTEX(cpa_mutex);
294 static int change_page_attr(unsigned long addr, unsigned long end,
303 if (end >= MODULES_END)
305 mutex_lock(&cpa_mutex);
306 pgdp = pgd_offset_k(addr);
310 next = pgd_addr_end(addr, end);
311 rc = walk_p4d_level(pgdp, addr, next, flags);
315 } while (pgdp++, addr = next, addr < end && !rc);
316 mutex_unlock(&cpa_mutex);
320 int __set_memory(unsigned long addr, int numpages, unsigned long flags)
323 flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
327 return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags);
330 #if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE)
332 static void ipte_range(pte_t *pte, unsigned long address, int nr)
336 if (test_facility(13)) {
337 __ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL);
340 for (i = 0; i < nr; i++) {
341 __ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL);
342 address += PAGE_SIZE;
347 void __kernel_map_pages(struct page *page, int numpages, int enable)
349 unsigned long address;
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);
360 for (j = 0; j < nr; j++) {
361 pte = clear_pte_bit(*ptep, __pgprot(_PAGE_INVALID));
363 address += PAGE_SIZE;
367 ipte_range(ptep, address, nr);
373 #endif /* CONFIG_DEBUG_PAGEALLOC */