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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 */
v5.4
  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/pgtable.h>
 11#include <asm/pgalloc.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)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	ptep = pte_offset(pmdp, addr);
 
 
 90	do {
 91		new = *ptep;
 92		if (pte_none(new))
 93			return -EINVAL;
 94		if (flags & SET_MEMORY_RO)
 95			new = pte_wrprotect(new);
 96		else if (flags & SET_MEMORY_RW)
 97			new = pte_mkwrite(pte_mkdirty(new));
 98		if (flags & SET_MEMORY_NX)
 99			pte_val(new) |= _PAGE_NOEXEC;
100		else if (flags & SET_MEMORY_X)
101			pte_val(new) &= ~_PAGE_NOEXEC;
102		pgt_set((unsigned long *)ptep, pte_val(new), addr, CRDTE_DTT_PAGE);
103		ptep++;
104		addr += PAGE_SIZE;
105		cond_resched();
106	} while (addr < end);
107	return 0;
108}
109
110static int split_pmd_page(pmd_t *pmdp, unsigned long addr)
111{
112	unsigned long pte_addr, prot;
113	pte_t *pt_dir, *ptep;
114	pmd_t new;
115	int i, ro, nx;
116
117	pt_dir = vmem_pte_alloc();
118	if (!pt_dir)
119		return -ENOMEM;
120	pte_addr = pmd_pfn(*pmdp) << PAGE_SHIFT;
121	ro = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_PROTECT);
122	nx = !!(pmd_val(*pmdp) & _SEGMENT_ENTRY_NOEXEC);
123	prot = pgprot_val(ro ? PAGE_KERNEL_RO : PAGE_KERNEL);
124	if (!nx)
125		prot &= ~_PAGE_NOEXEC;
126	ptep = pt_dir;
127	for (i = 0; i < PTRS_PER_PTE; i++) {
128		pte_val(*ptep) = pte_addr | prot;
129		pte_addr += PAGE_SIZE;
130		ptep++;
131	}
132	pmd_val(new) = __pa(pt_dir) | _SEGMENT_ENTRY;
133	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
134	update_page_count(PG_DIRECT_MAP_4K, PTRS_PER_PTE);
135	update_page_count(PG_DIRECT_MAP_1M, -1);
136	return 0;
137}
138
139static void modify_pmd_page(pmd_t *pmdp, unsigned long addr,
140			    unsigned long flags)
141{
142	pmd_t new = *pmdp;
143
144	if (flags & SET_MEMORY_RO)
145		new = pmd_wrprotect(new);
146	else if (flags & SET_MEMORY_RW)
147		new = pmd_mkwrite(pmd_mkdirty(new));
148	if (flags & SET_MEMORY_NX)
149		pmd_val(new) |= _SEGMENT_ENTRY_NOEXEC;
150	else if (flags & SET_MEMORY_X)
151		pmd_val(new) &= ~_SEGMENT_ENTRY_NOEXEC;
152	pgt_set((unsigned long *)pmdp, pmd_val(new), addr, CRDTE_DTT_SEGMENT);
153}
154
155static int walk_pmd_level(pud_t *pudp, unsigned long addr, unsigned long end,
156			  unsigned long flags)
157{
158	unsigned long next;
 
159	pmd_t *pmdp;
160	int rc = 0;
161
162	pmdp = pmd_offset(pudp, addr);
163	do {
164		if (pmd_none(*pmdp))
165			return -EINVAL;
166		next = pmd_addr_end(addr, end);
167		if (pmd_large(*pmdp)) {
168			if (addr & ~PMD_MASK || addr + PMD_SIZE > next) {
 
 
 
169				rc = split_pmd_page(pmdp, addr);
170				if (rc)
171					return rc;
172				continue;
173			}
174			modify_pmd_page(pmdp, addr, flags);
175		} else {
176			rc = walk_pte_level(pmdp, addr, next, flags);
177			if (rc)
178				return rc;
179		}
180		pmdp++;
181		addr = next;
182		cond_resched();
183	} while (addr < end);
184	return rc;
185}
186
187static int split_pud_page(pud_t *pudp, unsigned long addr)
188{
189	unsigned long pmd_addr, prot;
190	pmd_t *pm_dir, *pmdp;
191	pud_t new;
192	int i, ro, nx;
193
194	pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
195	if (!pm_dir)
196		return -ENOMEM;
197	pmd_addr = pud_pfn(*pudp) << PAGE_SHIFT;
198	ro = !!(pud_val(*pudp) & _REGION_ENTRY_PROTECT);
199	nx = !!(pud_val(*pudp) & _REGION_ENTRY_NOEXEC);
200	prot = pgprot_val(ro ? SEGMENT_KERNEL_RO : SEGMENT_KERNEL);
201	if (!nx)
202		prot &= ~_SEGMENT_ENTRY_NOEXEC;
203	pmdp = pm_dir;
204	for (i = 0; i < PTRS_PER_PMD; i++) {
205		pmd_val(*pmdp) = pmd_addr | prot;
206		pmd_addr += PMD_SIZE;
207		pmdp++;
208	}
209	pud_val(new) = __pa(pm_dir) | _REGION3_ENTRY;
210	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
211	update_page_count(PG_DIRECT_MAP_1M, PTRS_PER_PMD);
212	update_page_count(PG_DIRECT_MAP_2G, -1);
213	return 0;
214}
215
216static void modify_pud_page(pud_t *pudp, unsigned long addr,
217			    unsigned long flags)
218{
219	pud_t new = *pudp;
220
221	if (flags & SET_MEMORY_RO)
222		new = pud_wrprotect(new);
223	else if (flags & SET_MEMORY_RW)
224		new = pud_mkwrite(pud_mkdirty(new));
225	if (flags & SET_MEMORY_NX)
226		pud_val(new) |= _REGION_ENTRY_NOEXEC;
227	else if (flags & SET_MEMORY_X)
228		pud_val(new) &= ~_REGION_ENTRY_NOEXEC;
229	pgt_set((unsigned long *)pudp, pud_val(new), addr, CRDTE_DTT_REGION3);
230}
231
232static int walk_pud_level(p4d_t *p4d, unsigned long addr, unsigned long end,
233			  unsigned long flags)
234{
235	unsigned long next;
 
236	pud_t *pudp;
237	int rc = 0;
238
239	pudp = pud_offset(p4d, addr);
240	do {
241		if (pud_none(*pudp))
242			return -EINVAL;
243		next = pud_addr_end(addr, end);
244		if (pud_large(*pudp)) {
245			if (addr & ~PUD_MASK || addr + PUD_SIZE > next) {
 
 
 
246				rc = split_pud_page(pudp, addr);
247				if (rc)
248					break;
249				continue;
250			}
251			modify_pud_page(pudp, addr, flags);
252		} else {
253			rc = walk_pmd_level(pudp, addr, next, flags);
254		}
255		pudp++;
256		addr = next;
257		cond_resched();
258	} while (addr < end && !rc);
259	return rc;
260}
261
262static int walk_p4d_level(pgd_t *pgd, unsigned long addr, unsigned long end,
263			  unsigned long flags)
264{
265	unsigned long next;
266	p4d_t *p4dp;
267	int rc = 0;
268
269	p4dp = p4d_offset(pgd, addr);
270	do {
271		if (p4d_none(*p4dp))
272			return -EINVAL;
273		next = p4d_addr_end(addr, end);
274		rc = walk_pud_level(p4dp, addr, next, flags);
275		p4dp++;
276		addr = next;
277		cond_resched();
278	} while (addr < end && !rc);
279	return rc;
280}
281
282static DEFINE_MUTEX(cpa_mutex);
283
284static int change_page_attr(unsigned long addr, unsigned long end,
285			    unsigned long flags)
286{
287	unsigned long next;
288	int rc = -EINVAL;
289	pgd_t *pgdp;
290
291	if (addr == end)
292		return 0;
293	if (end >= MODULES_END)
294		return -EINVAL;
295	mutex_lock(&cpa_mutex);
296	pgdp = pgd_offset_k(addr);
297	do {
298		if (pgd_none(*pgdp))
299			break;
300		next = pgd_addr_end(addr, end);
301		rc = walk_p4d_level(pgdp, addr, next, flags);
302		if (rc)
303			break;
304		cond_resched();
305	} while (pgdp++, addr = next, addr < end && !rc);
306	mutex_unlock(&cpa_mutex);
307	return rc;
308}
309
310int __set_memory(unsigned long addr, int numpages, unsigned long flags)
311{
312	if (!MACHINE_HAS_NX)
313		flags &= ~(SET_MEMORY_NX | SET_MEMORY_X);
314	if (!flags)
315		return 0;
316	addr &= PAGE_MASK;
317	return change_page_attr(addr, addr + numpages * PAGE_SIZE, flags);
318}
319
320#ifdef CONFIG_DEBUG_PAGEALLOC
321
322static void ipte_range(pte_t *pte, unsigned long address, int nr)
323{
324	int i;
325
326	if (test_facility(13)) {
327		__ptep_ipte_range(address, nr - 1, pte, IPTE_GLOBAL);
328		return;
329	}
330	for (i = 0; i < nr; i++) {
331		__ptep_ipte(address, pte, 0, 0, IPTE_GLOBAL);
332		address += PAGE_SIZE;
333		pte++;
334	}
335}
336
337void __kernel_map_pages(struct page *page, int numpages, int enable)
338{
339	unsigned long address;
 
340	int nr, i, j;
341	pgd_t *pgd;
342	p4d_t *p4d;
343	pud_t *pud;
344	pmd_t *pmd;
345	pte_t *pte;
346
347	for (i = 0; i < numpages;) {
348		address = page_to_phys(page + i);
349		pgd = pgd_offset_k(address);
350		p4d = p4d_offset(pgd, address);
351		pud = pud_offset(p4d, address);
352		pmd = pmd_offset(pud, address);
353		pte = pte_offset_kernel(pmd, address);
354		nr = (unsigned long)pte >> ilog2(sizeof(long));
355		nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
356		nr = min(numpages - i, nr);
357		if (enable) {
358			for (j = 0; j < nr; j++) {
359				pte_val(*pte) &= ~_PAGE_INVALID;
 
360				address += PAGE_SIZE;
361				pte++;
362			}
363		} else {
364			ipte_range(pte, address, nr);
365		}
366		i += nr;
367	}
368}
369
370#ifdef CONFIG_HIBERNATION
371bool kernel_page_present(struct page *page)
372{
373	unsigned long addr;
374	int cc;
375
376	addr = page_to_phys(page);
377	asm volatile(
378		"	lra	%1,0(%1)\n"
379		"	ipm	%0\n"
380		"	srl	%0,28"
381		: "=d" (cc), "+a" (addr) : : "cc");
382	return cc == 0;
383}
384#endif /* CONFIG_HIBERNATION */
385
386#endif /* CONFIG_DEBUG_PAGEALLOC */