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v6.2
  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 */
v6.13.7
  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/proc_fs.h>
  8#include <linux/vmalloc.h>
  9#include <linux/mm.h>
 10#include <asm/cacheflush.h>
 11#include <asm/facility.h>
 12#include <asm/pgalloc.h>
 13#include <asm/kfence.h>
 14#include <asm/page.h>
 15#include <asm/asm.h>
 16#include <asm/set_memory.h>
 17
 18static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
 19{
 20	asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],1,0"
 21		     : [addr] "+a" (addr) : [skey] "d" (skey));
 22	return addr;
 23}
 24
 25void __storage_key_init_range(unsigned long start, unsigned long end)
 26{
 27	unsigned long boundary, size;
 28
 29	while (start < end) {
 30		if (MACHINE_HAS_EDAT1) {
 31			/* set storage keys for a 1MB frame */
 32			size = 1UL << 20;
 33			boundary = (start + size) & ~(size - 1);
 34			if (boundary <= end) {
 35				do {
 36					start = sske_frame(start, PAGE_DEFAULT_KEY);
 37				} while (start < boundary);
 38				continue;
 39			}
 40		}
 41		page_set_storage_key(start, PAGE_DEFAULT_KEY, 1);
 42		start += PAGE_SIZE;
 43	}
 44}
 45
 46#ifdef CONFIG_PROC_FS
 47atomic_long_t __bootdata_preserved(direct_pages_count[PG_DIRECT_MAP_MAX]);
 48
 49void arch_report_meminfo(struct seq_file *m)
 50{
 51	seq_printf(m, "DirectMap4k:    %8lu kB\n",
 52		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_4K]) << 2);
 53	seq_printf(m, "DirectMap1M:    %8lu kB\n",
 54		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_1M]) << 10);
 55	seq_printf(m, "DirectMap2G:    %8lu kB\n",
 56		   atomic_long_read(&direct_pages_count[PG_DIRECT_MAP_2G]) << 21);
 57}
 58#endif /* CONFIG_PROC_FS */
 59
 60static void pgt_set(unsigned long *old, unsigned long new, unsigned long addr,
 61		    unsigned long dtt)
 62{
 63	unsigned long *table, mask;
 64
 65	mask = 0;
 66	if (MACHINE_HAS_EDAT2) {
 67		switch (dtt) {
 68		case CRDTE_DTT_REGION3:
 69			mask = ~(PTRS_PER_PUD * sizeof(pud_t) - 1);
 70			break;
 71		case CRDTE_DTT_SEGMENT:
 72			mask = ~(PTRS_PER_PMD * sizeof(pmd_t) - 1);
 73			break;
 74		case CRDTE_DTT_PAGE:
 75			mask = ~(PTRS_PER_PTE * sizeof(pte_t) - 1);
 76			break;
 77		}
 78		table = (unsigned long *)((unsigned long)old & mask);
 79		crdte(*old, new, table, dtt, addr, get_lowcore()->kernel_asce.val);
 80	} else if (MACHINE_HAS_IDTE) {
 81		cspg(old, *old, new);
 82	} else {
 83		csp((unsigned int *)old + 1, *old, new);
 84	}
 85}
 86
 87static int walk_pte_level(pmd_t *pmdp, unsigned long addr, unsigned long end,
 88			  unsigned long flags)
 89{
 90	pte_t *ptep, new;
 91
 92	if (flags == SET_MEMORY_4K)
 93		return 0;
 94	ptep = pte_offset_kernel(pmdp, addr);
 95	do {
 96		new = *ptep;
 97		if (pte_none(new))
 98			return -EINVAL;
 99		if (flags & SET_MEMORY_RO)
100			new = pte_wrprotect(new);
101		else if (flags & SET_MEMORY_RW)
102			new = pte_mkwrite_novma(pte_mkdirty(new));
103		if (flags & SET_MEMORY_NX)
104			new = set_pte_bit(new, __pgprot(_PAGE_NOEXEC));
105		else if (flags & SET_MEMORY_X)
106			new = clear_pte_bit(new, __pgprot(_PAGE_NOEXEC));
107		if (flags & SET_MEMORY_INV) {
108			new = set_pte_bit(new, __pgprot(_PAGE_INVALID));
109		} else if (flags & SET_MEMORY_DEF) {
110			new = __pte(pte_val(new) & PAGE_MASK);
111			new = set_pte_bit(new, PAGE_KERNEL);
112			if (!MACHINE_HAS_NX)
113				new = clear_pte_bit(new, __pgprot(_PAGE_NOEXEC));
114		}
115		pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
116		ptep++;
117		addr += PAGE_SIZE;
118		cond_resched();
119	} while (addr < end);
120	return 0;
121}
122
123static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
124{
125	unsigned long pte_addr, prot;
126	pte_t *pt_dir, *ptep;
127	pmd_t new;
128	int i, ro, nx;
129
130	pt_dir = vmem_pte_alloc();
131	if (!pt_dir)
132		return -ENOMEM;
133	pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT;
134	ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT);
135	nx = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_NOEXEC);
136	prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
137	if (!nx)
138		prot &= ~_PAGE_NOEXEC;
139	ptep = pt_dir;
140	for (i = 0; i < PTRS_PER_PTE; i++) {
141		set_pte(ptep, __pte(pte_addr | prot));
142		pte_addr += PAGE_SIZE;
143		ptep++;
144	}
145	new = __pmd(__pa(pt_dir) | _SEGMENT_ENTRY);
146	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
147	update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE);
148	update_page_count(PG_DIRECT_MAP_1M, -1);
149	return 0;
150}
151
152static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
153			    unsigned long flags)
154{
155	pmd_t new = *pmdp;
156
157	if (flags & SET_MEMORY_RO)
158		new = pmd_wrprotect(new);
159	else if (flags & SET_MEMORY_RW)
160		new = pmd_mkwrite_novma(pmd_mkdirty(new));
161	if (flags & SET_MEMORY_NX)
162		new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
163	else if (flags & SET_MEMORY_X)
164		new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
165	if (flags & SET_MEMORY_INV) {
166		new = set_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_INVALID));
167	} else if (flags & SET_MEMORY_DEF) {
168		new = __pmd(pmd_val(new) & PMD_MASK);
169		new = set_pmd_bit(new, SEGMENT_KERNEL);
170		if (!MACHINE_HAS_NX)
171			new = clear_pmd_bit(new, __pgprot(_SEGMENT_ENTRY_NOEXEC));
172	}
173	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
174}
175
176static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
177			  unsigned long flags)
178{
179	unsigned long next;
180	int need_split;
181	pmd_t *pmdp;
182	int rc = 0;
183
184	pmdp = pmd_offset(pudp, addr);
185	do {
186		if (pmd_none(*pmdp))
187			return -EINVAL;
188		next = pmd_addr_end(addr, end);
189		if (pmd_leaf(*pmdp)) {
190			need_split  = !!(flags & SET_MEMORY_4K);
191			need_split |= !!(addr & ~PMD_MASK);
192			need_split |= !!(addr + PMD_SIZE > next);
193			if (need_split) {
194				rc = split_pmd_page(pmdp, addr);
195				if (rc)
196					return rc;
197				continue;
198			}
199			modify_pmd_page(pmdp, addr, flags);
200		} else {
201			rc = walk_pte_level(pmdp, addr, next, flags);
202			if (rc)
203				return rc;
204		}
205		pmdp++;
206		addr = next;
207		cond_resched();
208	} while (addr < end);
209	return rc;
210}
211
212static int split_pud_page(pud_t *pudp, unsigned long addr)
213{
214	unsigned long pmd_addr, prot;
215	pmd_t *pm_dir, *pmdp;
216	pud_t new;
217	int i, ro, nx;
218
219	pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
220	if (!pm_dir)
221		return -ENOMEM;
222	pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
223	ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
224	nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC);
225	prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
226	if (!nx)
227		prot &= ~_SEGMENT_ENTRY_NOEXEC;
228	pmdp = pm_dir;
229	for (i = 0; i < PTRS_PER_PMD; i++) {
230		set_pmd(pmdp, __pmd(pmd_addr | prot));
231		pmd_addr += PMD_SIZE;
232		pmdp++;
233	}
234	new = __pud(__pa(pm_dir) | _REGION3_ENTRY);
235	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
236	update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD);
237	update_page_count(PG_DIRECT_MAP_2G, -1);
238	return 0;
239}
240
241static void modify_pud_page(pud_t *pudp, unsigned long addr,
242			    unsigned long flags)
243{
244	pud_t new = *pudp;
245
246	if (flags & SET_MEMORY_RO)
247		new = pud_wrprotect(new);
248	else if (flags & SET_MEMORY_RW)
249		new = pud_mkwrite(pud_mkdirty(new));
250	if (flags & SET_MEMORY_NX)
251		new = set_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
252	else if (flags & SET_MEMORY_X)
253		new = clear_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
254	if (flags & SET_MEMORY_INV) {
255		new = set_pud_bit(new, __pgprot(_REGION_ENTRY_INVALID));
256	} else if (flags & SET_MEMORY_DEF) {
257		new = __pud(pud_val(new) & PUD_MASK);
258		new = set_pud_bit(new, REGION3_KERNEL);
259		if (!MACHINE_HAS_NX)
260			new = clear_pud_bit(new, __pgprot(_REGION_ENTRY_NOEXEC));
261	}
262	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
263}
264
265static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end,
266			  unsigned long flags)
267{
268	unsigned long next;
269	int need_split;
270	pud_t *pudp;
271	int rc = 0;
272
273	pudp = pud_offset(p4d, addr);
274	do {
275		if (pud_none(*pudp))
276			return -EINVAL;
277		next = pud_addr_end(addr, end);
278		if (pud_leaf(*pudp)) {
279			need_split  = !!(flags & SET_MEMORY_4K);
280			need_split |= !!(addr & ~PUD_MASK);
281			need_split |= !!(addr + PUD_SIZE > next);
282			if (need_split) {
283				rc = split_pud_page(pudp, addr);
284				if (rc)
285					break;
286				continue;
287			}
288			modify_pud_page(pudp, addr, flags);
289		} else {
290			rc = walk_pmd_level(pudp, addr, next, flags);
291		}
292		pudp++;
293		addr = next;
294		cond_resched();
295	} while (addr < end && !rc);
296	return rc;
297}
298
299static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end,
300			  unsigned long flags)
301{
302	unsigned long next;
303	p4d_t *p4dp;
304	int rc = 0;
305
306	p4dp = p4d_offset(pgd, addr);
307	do {
308		if (p4d_none(*p4dp))
309			return -EINVAL;
310		next = p4d_addr_end(addr, end);
311		rc = walk_pud_level(p4dp, addr, next, flags);
312		p4dp++;
313		addr = next;
314		cond_resched();
315	} while (addr < end && !rc);
316	return rc;
317}
318
319DEFINE_MUTEX(cpa_mutex);
320
321static int change_page_attr(unsigned long addr, unsigned long end,
322			    unsigned long flags)
323{
324	unsigned long next;
325	int rc = -EINVAL;
326	pgd_t *pgdp;
327
 
 
 
 
 
328	pgdp = pgd_offset_k(addr);
329	do {
330		if (pgd_none(*pgdp))
331			break;
332		next = pgd_addr_end(addr, end);
333		rc = walk_p4d_level(pgdp, addr, next, flags);
334		if (rc)
335			break;
336		cond_resched();
337	} while (pgdp++, addr = next, addr < end && !rc);
 
338	return rc;
339}
340
341static int change_page_attr_alias(unsigned long addr, unsigned long end,
342				  unsigned long flags)
343{
344	unsigned long alias, offset, va_start, va_end;
345	struct vm_struct *area;
346	int rc = 0;
347
348	/*
349	 * Changes to read-only permissions on kernel VA mappings are also
350	 * applied to the kernel direct mapping. Execute permissions are
351	 * intentionally not transferred to keep all allocated pages within
352	 * the direct mapping non-executable.
353	 */
354	flags &= SET_MEMORY_RO | SET_MEMORY_RW;
355	if (!flags)
356		return 0;
357	area = NULL;
358	while (addr < end) {
359		if (!area)
360			area = find_vm_area((void *)addr);
361		if (!area || !(area->flags & VM_ALLOC))
362			return 0;
363		va_start = (unsigned long)area->addr;
364		va_end = va_start + area->nr_pages * PAGE_SIZE;
365		offset = (addr - va_start) >> PAGE_SHIFT;
366		alias = (unsigned long)page_address(area->pages[offset]);
367		rc = change_page_attr(alias, alias + PAGE_SIZE, flags);
368		if (rc)
369			break;
370		addr += PAGE_SIZE;
371		if (addr >= va_end)
372			area = NULL;
373	}
374	return rc;
375}
376
377int __set_memory(unsigned long addr, unsigned long numpages, unsigned long flags)
378{
379	unsigned long end;
380	int rc;
381
382	if (!MACHINE_HAS_NX)
383		flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
384	if (!flags)
385		return 0;
386	if (!numpages)
387		return 0;
388	addr &= PAGE_MASK;
389	end = addr + numpages * PAGE_SIZE;
390	mutex_lock(&cpa_mutex);
391	rc = change_page_attr(addr, end, flags);
392	if (rc)
393		goto out;
394	rc = change_page_attr_alias(addr, end, flags);
395out:
396	mutex_unlock(&cpa_mutex);
397	return rc;
398}
399
400int set_direct_map_invalid_noflush(struct page *page)
401{
402	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_INV);
403}
404
405int set_direct_map_default_noflush(struct page *page)
406{
407	return __set_memory((unsigned long)page_to_virt(page), 1, SET_MEMORY_DEF);
408}
409
410int set_direct_map_valid_noflush(struct page *page, unsigned nr, bool valid)
411{
412	unsigned long flags;
413
414	if (valid)
415		flags = SET_MEMORY_DEF;
416	else
417		flags = SET_MEMORY_INV;
418
419	return __set_memory((unsigned long)page_to_virt(page), nr, flags);
420}
421
422bool kernel_page_present(struct page *page)
423{
424	unsigned long addr;
425	unsigned int cc;
426
427	addr = (unsigned long)page_address(page);
428	asm volatile(
429		"	lra	%[addr],0(%[addr])\n"
430		CC_IPM(cc)
431		: CC_OUT(cc, cc), [addr] "+a" (addr)
432		:
433		: CC_CLOBBER);
434	return CC_TRANSFORM(cc) == 0;
435}
436
437#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE)
438
439static void ipte_range(pte_t *pte, unsigned long address, int nr)
440{
441	int i;
442
443	if (test_facility(13)) {
444		__ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL);
445		return;
446	}
447	for (i = 0; i < nr; i++) {
448		__ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL);
449		address += PAGE_SIZE;
450		pte++;
451	}
452}
453
454void __kernel_map_pages(struct page *page, int numpages, int enable)
455{
456	unsigned long address;
457	pte_t *ptep, pte;
458	int nr, i, j;
459
460	for (i = 0; i < numpages;) {
461		address = (unsigned long)page_to_virt(page + i);
462		ptep = virt_to_kpte(address);
463		nr = (unsigned long)ptep >> ilog2(sizeof(long));
464		nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
465		nr = min(numpages - i, nr);
466		if (enable) {
467			for (j = 0; j < nr; j++) {
468				pte = clear_pte_bit(*ptep, __pgprot(_PAGE_INVALID));
469				set_pte(ptep, pte);
470				address += PAGE_SIZE;
471				ptep++;
472			}
473		} else {
474			ipte_range(ptep, address, nr);
475		}
476		i += nr;
477	}
478}
479
480#endif /* CONFIG_DEBUG_PAGEALLOC */