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/pgtable.h>
11 #include <asm/pgalloc.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],9,0"
18 : [addr] "+a" (addr) : [skey] "d" (skey));
22 void __storage_key_init_range(unsigned long start, unsigned long end)
24 unsigned long boundary, size;
26 if (!PAGE_DEFAULT_KEY)
29 if (MACHINE_HAS_EDAT1) {
30 /* set storage keys for a 1MB frame */
32 boundary = (start + size) & ~(size - 1);
33 if (boundary <= end) {
35 start = sske_frame(start, PAGE_DEFAULT_KEY);
36 } while (start < boundary);
40 page_set_storage_key(start, PAGE_DEFAULT_KEY, 0);
46 atomic_long_t direct_pages_count[PG_DIRECT_MAP_MAX];
48 void arch_report_meminfo(struct seq_file *m)
50 seq_printf(m, "DirectMap4k: %8lu kB\n",
51 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2);
52 seq_printf(m, "DirectMap1M: %8lu kB\n",
53 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10);
54 seq_printf(m, "DirectMap2G: %8lu kB\n",
55 atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21);
57 #endif /* CONFIG_PROC_FS */
59 static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
62 unsigned long table, mask;
65 if (MACHINE_HAS_EDAT2) {
67 case CRDTE_DTT_REGION3:
68 mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
70 case CRDTE_DTT_SEGMENT:
71 mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
74 mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1);
77 table = (unsigned long)old & mask;
78 crdte(*old, new, table, dtt, addr, S390_lowcore.kernel_asce);
79 } else if (MACHINE_HAS_IDTE) {
82 csp((unsigned int *)old + 1, *old, new);
86 static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
91 ptep = pte_offset(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 pte_val(new) |= _PAGE_NOEXEC;
102 else if (flags & SET_MEMORY_X)
103 pte_val(new) &= ~_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 pte_val(*ptep) = pte_addr | prot;
131 pte_addr += PAGE_SIZE;
134 pmd_val(new) = __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 pmd_val(new) |= _SEGMENT_ENTRY_NOEXEC;
152 else if (flags & SET_MEMORY_X)
153 pmd_val(new) &= ~_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,
164 pmdp = pmd_offset(pudp, addr);
168 next = pmd_addr_end(addr, end);
169 if (pmd_large(*pmdp)) {
170 if (addr & ~PMD_MASK || addr + PMD_SIZE > next) {
171 rc = split_pmd_page(pmdp, addr);
176 modify_pmd_page(pmdp, addr, flags);
178 rc = walk_pte_level(pmdp, addr, next, flags);
185 } while (addr < end);
189 static int split_pud_page(pud_t *pudp, unsigned long addr)
191 unsigned long pmd_addr, prot;
192 pmd_t *pm_dir, *pmdp;
196 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
199 pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
200 ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
201 nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC);
202 prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
204 prot &= ~_SEGMENT_ENTRY_NOEXEC;
206 for (i = 0; i < PTRS_PER_PMD; i++) {
207 pmd_val(*pmdp) = pmd_addr | prot;
208 pmd_addr += PMD_SIZE;
211 pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY;
212 pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
213 update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD);
214 update_page_count(PG_DIRECT_MAP_2G, -1);
218 static void modify_pud_page(pud_t *pudp, unsigned long addr,
223 if (flags & SET_MEMORY_RO)
224 new = pud_wrprotect(new);
225 else if (flags & SET_MEMORY_RW)
226 new = pud_mkwrite(pud_mkdirty(new));
227 if (flags & SET_MEMORY_NX)
228 pud_val(new) |= _REGION_ENTRY_NOEXEC;
229 else if (flags & SET_MEMORY_X)
230 pud_val(new) &= ~_REGION_ENTRY_NOEXEC;
231 pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
234 static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end,
241 pudp = pud_offset(p4d, addr);
245 next = pud_addr_end(addr, end);
246 if (pud_large(*pudp)) {
247 if (addr & ~PUD_MASK || addr + PUD_SIZE > next) {
248 rc = split_pud_page(pudp, addr);
253 modify_pud_page(pudp, addr, flags);
255 rc = walk_pmd_level(pudp, addr, next, flags);
260 } while (addr < end && !rc);
264 static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end,
271 p4dp = p4d_offset(pgd, addr);
275 next = p4d_addr_end(addr, end);
276 rc = walk_pud_level(p4dp, addr, next, flags);
280 } while (addr < end && !rc);
284 static DEFINE_MUTEX(cpa_mutex);
286 static int change_page_attr(unsigned long addr, unsigned long end,
295 if (end >= MODULES_END)
297 mutex_lock(&cpa_mutex);
298 pgdp = pgd_offset_k(addr);
302 next = pgd_addr_end(addr, end);
303 rc = walk_p4d_level(pgdp, addr, next, flags);
307 } while (pgdp++, addr = next, addr < end && !rc);
308 mutex_unlock(&cpa_mutex);
312 int __set_memory(unsigned long addr, int numpages, unsigned long flags)
315 flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
319 return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags);
322 #ifdef CONFIG_DEBUG_PAGEALLOC
324 static void ipte_range(pte_t *pte, unsigned long address, int nr)
328 if (test_facility(13)) {
329 __ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL);
332 for (i = 0; i < nr; i++) {
333 __ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL);
334 address += PAGE_SIZE;
339 void __kernel_map_pages(struct page *page, int numpages, int enable)
341 unsigned long address;
349 for (i = 0; i < numpages;) {
350 address = page_to_phys(page + i);
351 pgd = pgd_offset_k(address);
352 p4d = p4d_offset(pgd, address);
353 pud = pud_offset(p4d, address);
354 pmd = pmd_offset(pud, address);
355 pte = pte_offset_kernel(pmd, address);
356 nr = (unsigned long)pte >> 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_val(*pte) &= ~_PAGE_INVALID;
362 address += PAGE_SIZE;
366 ipte_range(pte, address, nr);
372 #ifdef CONFIG_HIBERNATION
373 bool kernel_page_present(struct page *page)
378 addr = page_to_phys(page);
383 : "=d" (cc), "+a" (addr) : : "cc");
386 #endif /* CONFIG_HIBERNATION */
388 #endif /* CONFIG_DEBUG_PAGEALLOC */