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v3.1
 
  1/*
  2 * SPARC64 Huge TLB page support.
  3 *
  4 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
  5 */
  6
  7#include <linux/init.h>
  8#include <linux/module.h>
  9#include <linux/fs.h>
 10#include <linux/mm.h>
 
 11#include <linux/hugetlb.h>
 12#include <linux/pagemap.h>
 13#include <linux/sysctl.h>
 14
 15#include <asm/mman.h>
 16#include <asm/pgalloc.h>
 17#include <asm/tlb.h>
 18#include <asm/tlbflush.h>
 19#include <asm/cacheflush.h>
 20#include <asm/mmu_context.h>
 21
 22/* Slightly simplified from the non-hugepage variant because by
 23 * definition we don't have to worry about any page coloring stuff
 24 */
 25#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL))
 26#define VA_EXCLUDE_END   (0xfffff80000000000UL + (1UL << 32UL))
 27
 28static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
 29							unsigned long addr,
 30							unsigned long len,
 31							unsigned long pgoff,
 32							unsigned long flags)
 33{
 34	struct mm_struct *mm = current->mm;
 35	struct vm_area_struct * vma;
 36	unsigned long task_size = TASK_SIZE;
 37	unsigned long start_addr;
 38
 39	if (test_thread_flag(TIF_32BIT))
 40		task_size = STACK_TOP32;
 41	if (unlikely(len >= VA_EXCLUDE_START))
 42		return -ENOMEM;
 43
 44	if (len > mm->cached_hole_size) {
 45	        start_addr = addr = mm->free_area_cache;
 46	} else {
 47	        start_addr = addr = TASK_UNMAPPED_BASE;
 48	        mm->cached_hole_size = 0;
 49	}
 50
 51	task_size -= len;
 52
 53full_search:
 54	addr = ALIGN(addr, HPAGE_SIZE);
 55
 56	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
 57		/* At this point:  (!vma || addr < vma->vm_end). */
 58		if (addr < VA_EXCLUDE_START &&
 59		    (addr + len) >= VA_EXCLUDE_START) {
 60			addr = VA_EXCLUDE_END;
 61			vma = find_vma(mm, VA_EXCLUDE_END);
 62		}
 63		if (unlikely(task_size < addr)) {
 64			if (start_addr != TASK_UNMAPPED_BASE) {
 65				start_addr = addr = TASK_UNMAPPED_BASE;
 66				mm->cached_hole_size = 0;
 67				goto full_search;
 68			}
 69			return -ENOMEM;
 70		}
 71		if (likely(!vma || addr + len <= vma->vm_start)) {
 72			/*
 73			 * Remember the place where we stopped the search:
 74			 */
 75			mm->free_area_cache = addr + len;
 76			return addr;
 77		}
 78		if (addr + mm->cached_hole_size < vma->vm_start)
 79		        mm->cached_hole_size = vma->vm_start - addr;
 80
 81		addr = ALIGN(vma->vm_end, HPAGE_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 
 82	}
 
 
 83}
 84
 85static unsigned long
 86hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 87				  const unsigned long len,
 88				  const unsigned long pgoff,
 89				  const unsigned long flags)
 90{
 91	struct vm_area_struct *vma;
 92	struct mm_struct *mm = current->mm;
 93	unsigned long addr = addr0;
 
 94
 95	/* This should only ever run for 32-bit processes.  */
 96	BUG_ON(!test_thread_flag(TIF_32BIT));
 97
 98	/* check if free_area_cache is useful for us */
 99	if (len <= mm->cached_hole_size) {
100 	        mm->cached_hole_size = 0;
101 		mm->free_area_cache = mm->mmap_base;
102 	}
103
104	/* either no address requested or can't fit in requested address hole */
105	addr = mm->free_area_cache & HPAGE_MASK;
106
107	/* make sure it can fit in the remaining address space */
108	if (likely(addr > len)) {
109		vma = find_vma(mm, addr-len);
110		if (!vma || addr <= vma->vm_start) {
111			/* remember the address as a hint for next time */
112			return (mm->free_area_cache = addr-len);
113		}
114	}
115
116	if (unlikely(mm->mmap_base < len))
117		goto bottomup;
118
119	addr = (mm->mmap_base-len) & HPAGE_MASK;
120
121	do {
122		/*
123		 * Lookup failure means no vma is above this address,
124		 * else if new region fits below vma->vm_start,
125		 * return with success:
126		 */
127		vma = find_vma(mm, addr);
128		if (likely(!vma || addr+len <= vma->vm_start)) {
129			/* remember the address as a hint for next time */
130			return (mm->free_area_cache = addr);
131		}
132
133 		/* remember the largest hole we saw so far */
134 		if (addr + mm->cached_hole_size < vma->vm_start)
135 		        mm->cached_hole_size = vma->vm_start - addr;
136
137		/* try just below the current vma->vm_start */
138		addr = (vma->vm_start-len) & HPAGE_MASK;
139	} while (likely(len < vma->vm_start));
140
141bottomup:
142	/*
143	 * A failed mmap() very likely causes application failure,
144	 * so fall back to the bottom-up function here. This scenario
145	 * can happen with large stack limits and large mmap()
146	 * allocations.
147	 */
148	mm->cached_hole_size = ~0UL;
149  	mm->free_area_cache = TASK_UNMAPPED_BASE;
150	addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
151	/*
152	 * Restore the topdown base:
153	 */
154	mm->free_area_cache = mm->mmap_base;
155	mm->cached_hole_size = ~0UL;
156
157	return addr;
158}
159
160unsigned long
161hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
162		unsigned long len, unsigned long pgoff, unsigned long flags)
163{
 
164	struct mm_struct *mm = current->mm;
165	struct vm_area_struct *vma;
166	unsigned long task_size = TASK_SIZE;
167
168	if (test_thread_flag(TIF_32BIT))
169		task_size = STACK_TOP32;
170
171	if (len & ~HPAGE_MASK)
172		return -EINVAL;
173	if (len > task_size)
174		return -ENOMEM;
175
176	if (flags & MAP_FIXED) {
177		if (prepare_hugepage_range(file, addr, len))
178			return -EINVAL;
179		return addr;
180	}
181
182	if (addr) {
183		addr = ALIGN(addr, HPAGE_SIZE);
184		vma = find_vma(mm, addr);
185		if (task_size - len >= addr &&
186		    (!vma || addr + len <= vma->vm_start))
187			return addr;
188	}
189	if (mm->get_unmapped_area == arch_get_unmapped_area)
190		return hugetlb_get_unmapped_area_bottomup(file, addr, len,
191				pgoff, flags);
192	else
193		return hugetlb_get_unmapped_area_topdown(file, addr, len,
194				pgoff, flags);
195}
196
197pte_t *huge_pte_alloc(struct mm_struct *mm,
198			unsigned long addr, unsigned long sz)
199{
200	pgd_t *pgd;
201	pud_t *pud;
202	pmd_t *pmd;
203	pte_t *pte = NULL;
204
205	/* We must align the address, because our caller will run
206	 * set_huge_pte_at() on whatever we return, which writes out
207	 * all of the sub-ptes for the hugepage range.  So we have
208	 * to give it the first such sub-pte.
209	 */
210	addr &= HPAGE_MASK;
211
212	pgd = pgd_offset(mm, addr);
213	pud = pud_alloc(mm, pgd, addr);
214	if (pud) {
215		pmd = pmd_alloc(mm, pud, addr);
216		if (pmd)
217			pte = pte_alloc_map(mm, NULL, pmd, addr);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
218	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
219	return pte;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
220}
221
222pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 
 
 
 
 
 
 
 
 
 
223{
224	pgd_t *pgd;
 
225	pud_t *pud;
226	pmd_t *pmd;
227	pte_t *pte = NULL;
228
229	addr &= HPAGE_MASK;
230
231	pgd = pgd_offset(mm, addr);
232	if (!pgd_none(*pgd)) {
233		pud = pud_offset(pgd, addr);
234		if (!pud_none(*pud)) {
235			pmd = pmd_offset(pud, addr);
236			if (!pmd_none(*pmd))
237				pte = pte_offset_map(pmd, addr);
238		}
239	}
240	return pte;
 
 
 
241}
242
243int huge_pmd_unshare(struct mm_struct *mm, unsigned long *addr, pte_t *ptep)
 
244{
245	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
246}
247
248void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
249		     pte_t *ptep, pte_t entry)
250{
251	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
252
253	if (!pte_present(*ptep) && pte_present(entry))
254		mm->context.huge_pte_count++;
255
256	addr &= HPAGE_MASK;
257	for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
258		set_pte_at(mm, addr, ptep, entry);
259		ptep++;
260		addr += PAGE_SIZE;
261		pte_val(entry) += PAGE_SIZE;
262	}
 
 
 
 
 
263}
264
265pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
266			      pte_t *ptep)
267{
 
 
268	pte_t entry;
269	int i;
270
271	entry = *ptep;
272	if (pte_present(entry))
273		mm->context.huge_pte_count--;
274
275	addr &= HPAGE_MASK;
 
 
 
 
 
 
276
277	for (i = 0; i < (1 << HUGETLB_PAGE_ORDER); i++) {
278		pte_clear(mm, addr, ptep);
279		addr += PAGE_SIZE;
280		ptep++;
281	}
282
283	return entry;
284}
285
286struct page *follow_huge_addr(struct mm_struct *mm,
287			      unsigned long address, int write)
288{
289	return ERR_PTR(-EINVAL);
 
 
 
 
 
 
 
290}
291
292int pmd_huge(pmd_t pmd)
293{
294	return 0;
 
295}
296
297int pud_huge(pud_t pud)
298{
299	return 0;
 
300}
301
302struct page *follow_huge_pmd(struct mm_struct *mm, unsigned long address,
303			     pmd_t *pmd, int write)
304{
305	return NULL;
 
 
 
 
306}
307
308static void context_reload(void *__data)
 
 
309{
310	struct mm_struct *mm = __data;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
311
312	if (mm == current->mm)
313		load_secondary_context(mm);
 
 
314}
315
316void hugetlb_prefault_arch_hook(struct mm_struct *mm)
 
 
317{
318	struct tsb_config *tp = &mm->context.tsb_block[MM_TSB_HUGE];
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
319
320	if (likely(tp->tsb != NULL))
 
 
 
 
 
 
 
 
321		return;
322
323	tsb_grow(mm, MM_TSB_HUGE, 0);
324	tsb_context_switch(mm);
325	smp_tsb_sync(mm);
 
 
326
327	/* On UltraSPARC-III+ and later, configure the second half of
328	 * the Data-TLB for huge pages.
329	 */
330	if (tlb_type == cheetah_plus) {
331		unsigned long ctx;
 
 
332
333		spin_lock(&ctx_alloc_lock);
334		ctx = mm->context.sparc64_ctx_val;
335		ctx &= ~CTX_PGSZ_MASK;
336		ctx |= CTX_PGSZ_BASE << CTX_PGSZ0_SHIFT;
337		ctx |= CTX_PGSZ_HUGE << CTX_PGSZ1_SHIFT;
338
339		if (ctx != mm->context.sparc64_ctx_val) {
340			/* When changing the page size fields, we
341			 * must perform a context flush so that no
342			 * stale entries match.  This flush must
343			 * occur with the original context register
344			 * settings.
345			 */
346			do_flush_tlb_mm(mm);
347
348			/* Reload the context register of all processors
349			 * also executing in this address space.
350			 */
351			mm->context.sparc64_ctx_val = ctx;
352			on_each_cpu(context_reload, mm, 0);
353		}
354		spin_unlock(&ctx_alloc_lock);
355	}
 
 
 
 
 
 
 
 
 
 
 
 
 
356}
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * SPARC64 Huge TLB page support.
  4 *
  5 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net)
  6 */
  7
 
 
  8#include <linux/fs.h>
  9#include <linux/mm.h>
 10#include <linux/sched/mm.h>
 11#include <linux/hugetlb.h>
 12#include <linux/pagemap.h>
 13#include <linux/sysctl.h>
 14
 15#include <asm/mman.h>
 16#include <asm/pgalloc.h>
 17#include <asm/tlb.h>
 18#include <asm/tlbflush.h>
 19#include <asm/cacheflush.h>
 20#include <asm/mmu_context.h>
 21
 22/* Slightly simplified from the non-hugepage variant because by
 23 * definition we don't have to worry about any page coloring stuff
 24 */
 
 
 25
 26static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *filp,
 27							unsigned long addr,
 28							unsigned long len,
 29							unsigned long pgoff,
 30							unsigned long flags)
 31{
 32	struct hstate *h = hstate_file(filp);
 
 33	unsigned long task_size = TASK_SIZE;
 34	struct vm_unmapped_area_info info;
 35
 36	if (test_thread_flag(TIF_32BIT))
 37		task_size = STACK_TOP32;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 38
 39	info.flags = 0;
 40	info.length = len;
 41	info.low_limit = TASK_UNMAPPED_BASE;
 42	info.high_limit = min(task_size, VA_EXCLUDE_START);
 43	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 44	info.align_offset = 0;
 45	addr = vm_unmapped_area(&info);
 46
 47	if ((addr & ~PAGE_MASK) && task_size > VA_EXCLUDE_END) {
 48		VM_BUG_ON(addr != -ENOMEM);
 49		info.low_limit = VA_EXCLUDE_END;
 50		info.high_limit = task_size;
 51		addr = vm_unmapped_area(&info);
 52	}
 53
 54	return addr;
 55}
 56
 57static unsigned long
 58hugetlb_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 59				  const unsigned long len,
 60				  const unsigned long pgoff,
 61				  const unsigned long flags)
 62{
 63	struct hstate *h = hstate_file(filp);
 64	struct mm_struct *mm = current->mm;
 65	unsigned long addr = addr0;
 66	struct vm_unmapped_area_info info;
 67
 68	/* This should only ever run for 32-bit processes.  */
 69	BUG_ON(!test_thread_flag(TIF_32BIT));
 70
 71	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
 72	info.length = len;
 73	info.low_limit = PAGE_SIZE;
 74	info.high_limit = mm->mmap_base;
 75	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
 76	info.align_offset = 0;
 77	addr = vm_unmapped_area(&info);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 78
 
 79	/*
 80	 * A failed mmap() very likely causes application failure,
 81	 * so fall back to the bottom-up function here. This scenario
 82	 * can happen with large stack limits and large mmap()
 83	 * allocations.
 84	 */
 85	if (addr & ~PAGE_MASK) {
 86		VM_BUG_ON(addr != -ENOMEM);
 87		info.flags = 0;
 88		info.low_limit = TASK_UNMAPPED_BASE;
 89		info.high_limit = STACK_TOP32;
 90		addr = vm_unmapped_area(&info);
 91	}
 
 92
 93	return addr;
 94}
 95
 96unsigned long
 97hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 98		unsigned long len, unsigned long pgoff, unsigned long flags)
 99{
100	struct hstate *h = hstate_file(file);
101	struct mm_struct *mm = current->mm;
102	struct vm_area_struct *vma;
103	unsigned long task_size = TASK_SIZE;
104
105	if (test_thread_flag(TIF_32BIT))
106		task_size = STACK_TOP32;
107
108	if (len & ~huge_page_mask(h))
109		return -EINVAL;
110	if (len > task_size)
111		return -ENOMEM;
112
113	if (flags & MAP_FIXED) {
114		if (prepare_hugepage_range(file, addr, len))
115			return -EINVAL;
116		return addr;
117	}
118
119	if (addr) {
120		addr = ALIGN(addr, huge_page_size(h));
121		vma = find_vma(mm, addr);
122		if (task_size - len >= addr &&
123		    (!vma || addr + len <= vm_start_gap(vma)))
124			return addr;
125	}
126	if (mm->get_unmapped_area == arch_get_unmapped_area)
127		return hugetlb_get_unmapped_area_bottomup(file, addr, len,
128				pgoff, flags);
129	else
130		return hugetlb_get_unmapped_area_topdown(file, addr, len,
131				pgoff, flags);
132}
133
134static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
 
135{
136	return entry;
137}
 
 
138
139static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift)
140{
141	unsigned long hugepage_size = _PAGE_SZ4MB_4V;
 
 
 
142
143	pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V;
144
145	switch (shift) {
146	case HPAGE_16GB_SHIFT:
147		hugepage_size = _PAGE_SZ16GB_4V;
148		pte_val(entry) |= _PAGE_PUD_HUGE;
149		break;
150	case HPAGE_2GB_SHIFT:
151		hugepage_size = _PAGE_SZ2GB_4V;
152		pte_val(entry) |= _PAGE_PMD_HUGE;
153		break;
154	case HPAGE_256MB_SHIFT:
155		hugepage_size = _PAGE_SZ256MB_4V;
156		pte_val(entry) |= _PAGE_PMD_HUGE;
157		break;
158	case HPAGE_SHIFT:
159		pte_val(entry) |= _PAGE_PMD_HUGE;
160		break;
161	case HPAGE_64K_SHIFT:
162		hugepage_size = _PAGE_SZ64K_4V;
163		break;
164	default:
165		WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift);
166	}
167
168	pte_val(entry) = pte_val(entry) | hugepage_size;
169	return entry;
170}
171
172static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift)
173{
174	if (tlb_type == hypervisor)
175		return sun4v_hugepage_shift_to_tte(entry, shift);
176	else
177		return sun4u_hugepage_shift_to_tte(entry, shift);
178}
179
180pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma,
181			 struct page *page, int writeable)
182{
183	unsigned int shift = huge_page_shift(hstate_vma(vma));
184	pte_t pte;
185
186	pte = hugepage_shift_to_tte(entry, shift);
187
188#ifdef CONFIG_SPARC64
189	/* If this vma has ADI enabled on it, turn on TTE.mcd
190	 */
191	if (vma->vm_flags & VM_SPARC_ADI)
192		return pte_mkmcd(pte);
193	else
194		return pte_mknotmcd(pte);
195#else
196	return pte;
197#endif
198}
199
200static unsigned int sun4v_huge_tte_to_shift(pte_t entry)
201{
202	unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V;
203	unsigned int shift;
204
205	switch (tte_szbits) {
206	case _PAGE_SZ16GB_4V:
207		shift = HPAGE_16GB_SHIFT;
208		break;
209	case _PAGE_SZ2GB_4V:
210		shift = HPAGE_2GB_SHIFT;
211		break;
212	case _PAGE_SZ256MB_4V:
213		shift = HPAGE_256MB_SHIFT;
214		break;
215	case _PAGE_SZ4MB_4V:
216		shift = REAL_HPAGE_SHIFT;
217		break;
218	case _PAGE_SZ64K_4V:
219		shift = HPAGE_64K_SHIFT;
220		break;
221	default:
222		shift = PAGE_SHIFT;
223		break;
224	}
225	return shift;
226}
227
228static unsigned int sun4u_huge_tte_to_shift(pte_t entry)
229{
230	unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U;
231	unsigned int shift;
232
233	switch (tte_szbits) {
234	case _PAGE_SZ256MB_4U:
235		shift = HPAGE_256MB_SHIFT;
236		break;
237	case _PAGE_SZ4MB_4U:
238		shift = REAL_HPAGE_SHIFT;
239		break;
240	case _PAGE_SZ64K_4U:
241		shift = HPAGE_64K_SHIFT;
242		break;
243	default:
244		shift = PAGE_SHIFT;
245		break;
246	}
247	return shift;
248}
249
250static unsigned int huge_tte_to_shift(pte_t entry)
251{
252	unsigned long shift;
253
254	if (tlb_type == hypervisor)
255		shift = sun4v_huge_tte_to_shift(entry);
256	else
257		shift = sun4u_huge_tte_to_shift(entry);
258
259	if (shift == PAGE_SHIFT)
260		WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n",
261			  pte_val(entry));
262
263	return shift;
264}
265
266static unsigned long huge_tte_to_size(pte_t pte)
267{
268	unsigned long size = 1UL << huge_tte_to_shift(pte);
269
270	if (size == REAL_HPAGE_SIZE)
271		size = HPAGE_SIZE;
272	return size;
273}
274
275pte_t *huge_pte_alloc(struct mm_struct *mm,
276			unsigned long addr, unsigned long sz)
277{
278	pgd_t *pgd;
279	p4d_t *p4d;
280	pud_t *pud;
281	pmd_t *pmd;
 
 
 
282
283	pgd = pgd_offset(mm, addr);
284	p4d = p4d_offset(pgd, addr);
285	pud = pud_alloc(mm, p4d, addr);
286	if (!pud)
287		return NULL;
288	if (sz >= PUD_SIZE)
289		return (pte_t *)pud;
290	pmd = pmd_alloc(mm, pud, addr);
291	if (!pmd)
292		return NULL;
293	if (sz >= PMD_SIZE)
294		return (pte_t *)pmd;
295	return pte_alloc_map(mm, pmd, addr);
296}
297
298pte_t *huge_pte_offset(struct mm_struct *mm,
299		       unsigned long addr, unsigned long sz)
300{
301	pgd_t *pgd;
302	p4d_t *p4d;
303	pud_t *pud;
304	pmd_t *pmd;
305
306	pgd = pgd_offset(mm, addr);
307	if (pgd_none(*pgd))
308		return NULL;
309	p4d = p4d_offset(pgd, addr);
310	if (p4d_none(*p4d))
311		return NULL;
312	pud = pud_offset(p4d, addr);
313	if (pud_none(*pud))
314		return NULL;
315	if (is_hugetlb_pud(*pud))
316		return (pte_t *)pud;
317	pmd = pmd_offset(pud, addr);
318	if (pmd_none(*pmd))
319		return NULL;
320	if (is_hugetlb_pmd(*pmd))
321		return (pte_t *)pmd;
322	return pte_offset_map(pmd, addr);
323}
324
325void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
326		     pte_t *ptep, pte_t entry)
327{
328	unsigned int nptes, orig_shift, shift;
329	unsigned long i, size;
330	pte_t orig;
331
332	size = huge_tte_to_size(entry);
333
334	shift = PAGE_SHIFT;
335	if (size >= PUD_SIZE)
336		shift = PUD_SHIFT;
337	else if (size >= PMD_SIZE)
338		shift = PMD_SHIFT;
339	else
340		shift = PAGE_SHIFT;
341
342	nptes = size >> shift;
343
344	if (!pte_present(*ptep) && pte_present(entry))
345		mm->context.hugetlb_pte_count += nptes;
346
347	addr &= ~(size - 1);
348	orig = *ptep;
349	orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig);
350
351	for (i = 0; i < nptes; i++)
352		ptep[i] = __pte(pte_val(entry) + (i << shift));
353
354	maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift);
355	/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
356	if (size == HPAGE_SIZE)
357		maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0,
358				    orig_shift);
359}
360
361pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
362			      pte_t *ptep)
363{
364	unsigned int i, nptes, orig_shift, shift;
365	unsigned long size;
366	pte_t entry;
 
367
368	entry = *ptep;
369	size = huge_tte_to_size(entry);
 
370
371	shift = PAGE_SHIFT;
372	if (size >= PUD_SIZE)
373		shift = PUD_SHIFT;
374	else if (size >= PMD_SIZE)
375		shift = PMD_SHIFT;
376	else
377		shift = PAGE_SHIFT;
378
379	nptes = size >> shift;
380	orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry);
 
 
 
381
382	if (pte_present(entry))
383		mm->context.hugetlb_pte_count -= nptes;
384
385	addr &= ~(size - 1);
386	for (i = 0; i < nptes; i++)
387		ptep[i] = __pte(0UL);
388
389	maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift);
390	/* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */
391	if (size == HPAGE_SIZE)
392		maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0,
393				    orig_shift);
394
395	return entry;
396}
397
398int pmd_huge(pmd_t pmd)
399{
400	return !pmd_none(pmd) &&
401		(pmd_val(pmd) & (_PAGE_VALID|_PAGE_PMD_HUGE)) != _PAGE_VALID;
402}
403
404int pud_huge(pud_t pud)
405{
406	return !pud_none(pud) &&
407		(pud_val(pud) & (_PAGE_VALID|_PAGE_PUD_HUGE)) != _PAGE_VALID;
408}
409
410static void hugetlb_free_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
411			   unsigned long addr)
412{
413	pgtable_t token = pmd_pgtable(*pmd);
414
415	pmd_clear(pmd);
416	pte_free_tlb(tlb, token, addr);
417	mm_dec_nr_ptes(tlb->mm);
418}
419
420static void hugetlb_free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
421				   unsigned long addr, unsigned long end,
422				   unsigned long floor, unsigned long ceiling)
423{
424	pmd_t *pmd;
425	unsigned long next;
426	unsigned long start;
427
428	start = addr;
429	pmd = pmd_offset(pud, addr);
430	do {
431		next = pmd_addr_end(addr, end);
432		if (pmd_none(*pmd))
433			continue;
434		if (is_hugetlb_pmd(*pmd))
435			pmd_clear(pmd);
436		else
437			hugetlb_free_pte_range(tlb, pmd, addr);
438	} while (pmd++, addr = next, addr != end);
439
440	start &= PUD_MASK;
441	if (start < floor)
442		return;
443	if (ceiling) {
444		ceiling &= PUD_MASK;
445		if (!ceiling)
446			return;
447	}
448	if (end - 1 > ceiling - 1)
449		return;
450
451	pmd = pmd_offset(pud, start);
452	pud_clear(pud);
453	pmd_free_tlb(tlb, pmd, start);
454	mm_dec_nr_pmds(tlb->mm);
455}
456
457static void hugetlb_free_pud_range(struct mmu_gather *tlb, p4d_t *p4d,
458				   unsigned long addr, unsigned long end,
459				   unsigned long floor, unsigned long ceiling)
460{
461	pud_t *pud;
462	unsigned long next;
463	unsigned long start;
464
465	start = addr;
466	pud = pud_offset(p4d, addr);
467	do {
468		next = pud_addr_end(addr, end);
469		if (pud_none_or_clear_bad(pud))
470			continue;
471		if (is_hugetlb_pud(*pud))
472			pud_clear(pud);
473		else
474			hugetlb_free_pmd_range(tlb, pud, addr, next, floor,
475					       ceiling);
476	} while (pud++, addr = next, addr != end);
477
478	start &= PGDIR_MASK;
479	if (start < floor)
480		return;
481	if (ceiling) {
482		ceiling &= PGDIR_MASK;
483		if (!ceiling)
484			return;
485	}
486	if (end - 1 > ceiling - 1)
487		return;
488
489	pud = pud_offset(p4d, start);
490	p4d_clear(p4d);
491	pud_free_tlb(tlb, pud, start);
492	mm_dec_nr_puds(tlb->mm);
493}
494
495void hugetlb_free_pgd_range(struct mmu_gather *tlb,
496			    unsigned long addr, unsigned long end,
497			    unsigned long floor, unsigned long ceiling)
498{
499	pgd_t *pgd;
500	p4d_t *p4d;
501	unsigned long next;
502
503	addr &= PMD_MASK;
504	if (addr < floor) {
505		addr += PMD_SIZE;
506		if (!addr)
507			return;
508	}
509	if (ceiling) {
510		ceiling &= PMD_MASK;
511		if (!ceiling)
512			return;
 
 
 
 
 
 
 
 
 
 
 
 
513	}
514	if (end - 1 > ceiling - 1)
515		end -= PMD_SIZE;
516	if (addr > end - 1)
517		return;
518
519	pgd = pgd_offset(tlb->mm, addr);
520	p4d = p4d_offset(pgd, addr);
521	do {
522		next = p4d_addr_end(addr, end);
523		if (p4d_none_or_clear_bad(p4d))
524			continue;
525		hugetlb_free_pud_range(tlb, p4d, addr, next, floor, ceiling);
526	} while (p4d++, addr = next, addr != end);
527}