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v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  IBM System z Huge TLB Page Support for Kernel.
  4 *
  5 *    Copyright IBM Corp. 2007,2020
  6 *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
  7 */
  8
  9#define KMSG_COMPONENT "hugetlb"
 10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 11
 12#include <asm/pgalloc.h>
 13#include <linux/mm.h>
 14#include <linux/hugetlb.h>
 15#include <linux/mman.h>
 16#include <linux/sched/mm.h>
 17#include <linux/security.h>
 18
 19/*
 20 * If the bit selected by single-bit bitmask "a" is set within "x", move
 21 * it to the position indicated by single-bit bitmask "b".
 22 */
 23#define move_set_bit(x, a, b)	(((x) & (a)) >> ilog2(a) << ilog2(b))
 24
 25static inline unsigned long __pte_to_rste(pte_t pte)
 26{
 27	unsigned long rste;
 28
 29	/*
 30	 * Convert encoding		  pte bits	pmd / pud bits
 31	 *				lIR.uswrdy.p	dy..R...I...wr
 32	 * empty			010.000000.0 -> 00..0...1...00
 33	 * prot-none, clean, old	111.000000.1 -> 00..1...1...00
 34	 * prot-none, clean, young	111.000001.1 -> 01..1...1...00
 35	 * prot-none, dirty, old	111.000010.1 -> 10..1...1...00
 36	 * prot-none, dirty, young	111.000011.1 -> 11..1...1...00
 37	 * read-only, clean, old	111.000100.1 -> 00..1...1...01
 38	 * read-only, clean, young	101.000101.1 -> 01..1...0...01
 39	 * read-only, dirty, old	111.000110.1 -> 10..1...1...01
 40	 * read-only, dirty, young	101.000111.1 -> 11..1...0...01
 41	 * read-write, clean, old	111.001100.1 -> 00..1...1...11
 42	 * read-write, clean, young	101.001101.1 -> 01..1...0...11
 43	 * read-write, dirty, old	110.001110.1 -> 10..0...1...11
 44	 * read-write, dirty, young	100.001111.1 -> 11..0...0...11
 45	 * HW-bits: R read-only, I invalid
 46	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
 47	 *	    u unused, l large
 48	 */
 49	if (pte_present(pte)) {
 50		rste = pte_val(pte) & PAGE_MASK;
 51		rste |= move_set_bit(pte_val(pte), _PAGE_READ,
 52				     _SEGMENT_ENTRY_READ);
 53		rste |= move_set_bit(pte_val(pte), _PAGE_WRITE,
 54				     _SEGMENT_ENTRY_WRITE);
 55		rste |= move_set_bit(pte_val(pte), _PAGE_INVALID,
 56				     _SEGMENT_ENTRY_INVALID);
 57		rste |= move_set_bit(pte_val(pte), _PAGE_PROTECT,
 58				     _SEGMENT_ENTRY_PROTECT);
 59		rste |= move_set_bit(pte_val(pte), _PAGE_DIRTY,
 60				     _SEGMENT_ENTRY_DIRTY);
 61		rste |= move_set_bit(pte_val(pte), _PAGE_YOUNG,
 62				     _SEGMENT_ENTRY_YOUNG);
 63#ifdef CONFIG_MEM_SOFT_DIRTY
 64		rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
 65				     _SEGMENT_ENTRY_SOFT_DIRTY);
 66#endif
 67		rste |= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
 68				     _SEGMENT_ENTRY_NOEXEC);
 69	} else
 70		rste = _SEGMENT_ENTRY_EMPTY;
 71	return rste;
 72}
 73
 74static inline pte_t __rste_to_pte(unsigned long rste)
 75{
 76	unsigned long pteval;
 77	int present;
 78
 79	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
 80		present = pud_present(__pud(rste));
 81	else
 82		present = pmd_present(__pmd(rste));
 83
 84	/*
 85	 * Convert encoding		pmd / pud bits	    pte bits
 86	 *				dy..R...I...wr	  lIR.uswrdy.p
 87	 * empty			00..0...1...00 -> 010.000000.0
 88	 * prot-none, clean, old	00..1...1...00 -> 111.000000.1
 89	 * prot-none, clean, young	01..1...1...00 -> 111.000001.1
 90	 * prot-none, dirty, old	10..1...1...00 -> 111.000010.1
 91	 * prot-none, dirty, young	11..1...1...00 -> 111.000011.1
 92	 * read-only, clean, old	00..1...1...01 -> 111.000100.1
 93	 * read-only, clean, young	01..1...0...01 -> 101.000101.1
 94	 * read-only, dirty, old	10..1...1...01 -> 111.000110.1
 95	 * read-only, dirty, young	11..1...0...01 -> 101.000111.1
 96	 * read-write, clean, old	00..1...1...11 -> 111.001100.1
 97	 * read-write, clean, young	01..1...0...11 -> 101.001101.1
 98	 * read-write, dirty, old	10..0...1...11 -> 110.001110.1
 99	 * read-write, dirty, young	11..0...0...11 -> 100.001111.1
100	 * HW-bits: R read-only, I invalid
101	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
102	 *	    u unused, l large
103	 */
104	if (present) {
105		pteval = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
106		pteval |= _PAGE_LARGE | _PAGE_PRESENT;
107		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_READ, _PAGE_READ);
108		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE, _PAGE_WRITE);
109		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID, _PAGE_INVALID);
110		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT, _PAGE_PROTECT);
111		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY, _PAGE_DIRTY);
112		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG, _PAGE_YOUNG);
113#ifdef CONFIG_MEM_SOFT_DIRTY
114		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY, _PAGE_SOFT_DIRTY);
115#endif
116		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC, _PAGE_NOEXEC);
117	} else
118		pteval = _PAGE_INVALID;
119	return __pte(pteval);
120}
121
122static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
123{
124	struct page *page;
125	unsigned long size, paddr;
126
127	if (!mm_uses_skeys(mm) ||
128	    rste & _SEGMENT_ENTRY_INVALID)
129		return;
130
131	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
132		page = pud_page(__pud(rste));
133		size = PUD_SIZE;
134		paddr = rste & PUD_MASK;
135	} else {
136		page = pmd_page(__pmd(rste));
137		size = PMD_SIZE;
138		paddr = rste & PMD_MASK;
139	}
140
141	if (!test_and_set_bit(PG_arch_1, &page->flags))
142		__storage_key_init_range(paddr, paddr + size - 1);
143}
144
145void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
146		     pte_t *ptep, pte_t pte)
147{
148	unsigned long rste;
149
150	rste = __pte_to_rste(pte);
151	if (!MACHINE_HAS_NX)
152		rste &= ~_SEGMENT_ENTRY_NOEXEC;
153
154	/* Set correct table type for 2G hugepages */
155	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
156		if (likely(pte_present(pte)))
157			rste |= _REGION3_ENTRY_LARGE;
158		rste |= _REGION_ENTRY_TYPE_R3;
159	} else if (likely(pte_present(pte)))
160		rste |= _SEGMENT_ENTRY_LARGE;
161
162	clear_huge_pte_skeys(mm, rste);
163	set_pte(ptep, __pte(rste));
164}
165
 
 
 
 
 
 
166pte_t huge_ptep_get(pte_t *ptep)
167{
168	return __rste_to_pte(pte_val(*ptep));
169}
170
171pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
172			      unsigned long addr, pte_t *ptep)
173{
174	pte_t pte = huge_ptep_get(ptep);
175	pmd_t *pmdp = (pmd_t *) ptep;
176	pud_t *pudp = (pud_t *) ptep;
177
178	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
179		pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
180	else
181		pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
182	return pte;
183}
184
185pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
186			unsigned long addr, unsigned long sz)
187{
188	pgd_t *pgdp;
189	p4d_t *p4dp;
190	pud_t *pudp;
191	pmd_t *pmdp = NULL;
192
193	pgdp = pgd_offset(mm, addr);
194	p4dp = p4d_alloc(mm, pgdp, addr);
195	if (p4dp) {
196		pudp = pud_alloc(mm, p4dp, addr);
197		if (pudp) {
198			if (sz == PUD_SIZE)
199				return (pte_t *) pudp;
200			else if (sz == PMD_SIZE)
201				pmdp = pmd_alloc(mm, pudp, addr);
202		}
203	}
204	return (pte_t *) pmdp;
205}
206
207pte_t *huge_pte_offset(struct mm_struct *mm,
208		       unsigned long addr, unsigned long sz)
209{
210	pgd_t *pgdp;
211	p4d_t *p4dp;
212	pud_t *pudp;
213	pmd_t *pmdp = NULL;
214
215	pgdp = pgd_offset(mm, addr);
216	if (pgd_present(*pgdp)) {
217		p4dp = p4d_offset(pgdp, addr);
218		if (p4d_present(*p4dp)) {
219			pudp = pud_offset(p4dp, addr);
220			if (pud_present(*pudp)) {
221				if (pud_large(*pudp))
222					return (pte_t *) pudp;
223				pmdp = pmd_offset(pudp, addr);
224			}
225		}
226	}
227	return (pte_t *) pmdp;
228}
229
230int pmd_huge(pmd_t pmd)
231{
232	return pmd_large(pmd);
233}
234
235int pud_huge(pud_t pud)
236{
237	return pud_large(pud);
238}
239
240bool __init arch_hugetlb_valid_size(unsigned long size)
241{
242	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
243		return true;
244	else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE)
245		return true;
246	else
247		return false;
248}
249
250static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
251		unsigned long addr, unsigned long len,
252		unsigned long pgoff, unsigned long flags)
253{
254	struct hstate *h = hstate_file(file);
255	struct vm_unmapped_area_info info;
256
257	info.flags = 0;
258	info.length = len;
259	info.low_limit = current->mm->mmap_base;
260	info.high_limit = TASK_SIZE;
261	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
262	info.align_offset = 0;
263	return vm_unmapped_area(&info);
264}
265
266static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
267		unsigned long addr0, unsigned long len,
268		unsigned long pgoff, unsigned long flags)
269{
270	struct hstate *h = hstate_file(file);
271	struct vm_unmapped_area_info info;
272	unsigned long addr;
273
274	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
275	info.length = len;
276	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
277	info.high_limit = current->mm->mmap_base;
278	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
279	info.align_offset = 0;
280	addr = vm_unmapped_area(&info);
281
282	/*
283	 * A failed mmap() very likely causes application failure,
284	 * so fall back to the bottom-up function here. This scenario
285	 * can happen with large stack limits and large mmap()
286	 * allocations.
287	 */
288	if (addr & ~PAGE_MASK) {
289		VM_BUG_ON(addr != -ENOMEM);
290		info.flags = 0;
291		info.low_limit = TASK_UNMAPPED_BASE;
292		info.high_limit = TASK_SIZE;
293		addr = vm_unmapped_area(&info);
294	}
295
296	return addr;
297}
298
299unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
300		unsigned long len, unsigned long pgoff, unsigned long flags)
301{
302	struct hstate *h = hstate_file(file);
303	struct mm_struct *mm = current->mm;
304	struct vm_area_struct *vma;
305
306	if (len & ~huge_page_mask(h))
307		return -EINVAL;
308	if (len > TASK_SIZE - mmap_min_addr)
309		return -ENOMEM;
310
311	if (flags & MAP_FIXED) {
312		if (prepare_hugepage_range(file, addr, len))
313			return -EINVAL;
314		goto check_asce_limit;
315	}
316
317	if (addr) {
318		addr = ALIGN(addr, huge_page_size(h));
319		vma = find_vma(mm, addr);
320		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
321		    (!vma || addr + len <= vm_start_gap(vma)))
322			goto check_asce_limit;
323	}
324
325	if (mm->get_unmapped_area == arch_get_unmapped_area)
326		addr = hugetlb_get_unmapped_area_bottomup(file, addr, len,
327				pgoff, flags);
328	else
329		addr = hugetlb_get_unmapped_area_topdown(file, addr, len,
330				pgoff, flags);
331	if (offset_in_page(addr))
332		return addr;
333
334check_asce_limit:
335	return check_asce_limit(mm, addr, len);
336}
v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  IBM System z Huge TLB Page Support for Kernel.
  4 *
  5 *    Copyright IBM Corp. 2007,2020
  6 *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
  7 */
  8
  9#define KMSG_COMPONENT "hugetlb"
 10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 11
 12#include <asm/pgalloc.h>
 13#include <linux/mm.h>
 14#include <linux/hugetlb.h>
 15#include <linux/mman.h>
 16#include <linux/sched/mm.h>
 17#include <linux/security.h>
 18
 19/*
 20 * If the bit selected by single-bit bitmask "a" is set within "x", move
 21 * it to the position indicated by single-bit bitmask "b".
 22 */
 23#define move_set_bit(x, a, b)	(((x) & (a)) >> ilog2(a) << ilog2(b))
 24
 25static inline unsigned long __pte_to_rste(pte_t pte)
 26{
 27	unsigned long rste;
 28
 29	/*
 30	 * Convert encoding		  pte bits	pmd / pud bits
 31	 *				lIR.uswrdy.p	dy..R...I...wr
 32	 * empty			010.000000.0 -> 00..0...1...00
 33	 * prot-none, clean, old	111.000000.1 -> 00..1...1...00
 34	 * prot-none, clean, young	111.000001.1 -> 01..1...1...00
 35	 * prot-none, dirty, old	111.000010.1 -> 10..1...1...00
 36	 * prot-none, dirty, young	111.000011.1 -> 11..1...1...00
 37	 * read-only, clean, old	111.000100.1 -> 00..1...1...01
 38	 * read-only, clean, young	101.000101.1 -> 01..1...0...01
 39	 * read-only, dirty, old	111.000110.1 -> 10..1...1...01
 40	 * read-only, dirty, young	101.000111.1 -> 11..1...0...01
 41	 * read-write, clean, old	111.001100.1 -> 00..1...1...11
 42	 * read-write, clean, young	101.001101.1 -> 01..1...0...11
 43	 * read-write, dirty, old	110.001110.1 -> 10..0...1...11
 44	 * read-write, dirty, young	100.001111.1 -> 11..0...0...11
 45	 * HW-bits: R read-only, I invalid
 46	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
 47	 *	    u unused, l large
 48	 */
 49	if (pte_present(pte)) {
 50		rste = pte_val(pte) & PAGE_MASK;
 51		rste |= move_set_bit(pte_val(pte), _PAGE_READ,
 52				     _SEGMENT_ENTRY_READ);
 53		rste |= move_set_bit(pte_val(pte), _PAGE_WRITE,
 54				     _SEGMENT_ENTRY_WRITE);
 55		rste |= move_set_bit(pte_val(pte), _PAGE_INVALID,
 56				     _SEGMENT_ENTRY_INVALID);
 57		rste |= move_set_bit(pte_val(pte), _PAGE_PROTECT,
 58				     _SEGMENT_ENTRY_PROTECT);
 59		rste |= move_set_bit(pte_val(pte), _PAGE_DIRTY,
 60				     _SEGMENT_ENTRY_DIRTY);
 61		rste |= move_set_bit(pte_val(pte), _PAGE_YOUNG,
 62				     _SEGMENT_ENTRY_YOUNG);
 63#ifdef CONFIG_MEM_SOFT_DIRTY
 64		rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
 65				     _SEGMENT_ENTRY_SOFT_DIRTY);
 66#endif
 67		rste |= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
 68				     _SEGMENT_ENTRY_NOEXEC);
 69	} else
 70		rste = _SEGMENT_ENTRY_EMPTY;
 71	return rste;
 72}
 73
 74static inline pte_t __rste_to_pte(unsigned long rste)
 75{
 76	unsigned long pteval;
 77	int present;
 78
 79	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
 80		present = pud_present(__pud(rste));
 81	else
 82		present = pmd_present(__pmd(rste));
 83
 84	/*
 85	 * Convert encoding		pmd / pud bits	    pte bits
 86	 *				dy..R...I...wr	  lIR.uswrdy.p
 87	 * empty			00..0...1...00 -> 010.000000.0
 88	 * prot-none, clean, old	00..1...1...00 -> 111.000000.1
 89	 * prot-none, clean, young	01..1...1...00 -> 111.000001.1
 90	 * prot-none, dirty, old	10..1...1...00 -> 111.000010.1
 91	 * prot-none, dirty, young	11..1...1...00 -> 111.000011.1
 92	 * read-only, clean, old	00..1...1...01 -> 111.000100.1
 93	 * read-only, clean, young	01..1...0...01 -> 101.000101.1
 94	 * read-only, dirty, old	10..1...1...01 -> 111.000110.1
 95	 * read-only, dirty, young	11..1...0...01 -> 101.000111.1
 96	 * read-write, clean, old	00..1...1...11 -> 111.001100.1
 97	 * read-write, clean, young	01..1...0...11 -> 101.001101.1
 98	 * read-write, dirty, old	10..0...1...11 -> 110.001110.1
 99	 * read-write, dirty, young	11..0...0...11 -> 100.001111.1
100	 * HW-bits: R read-only, I invalid
101	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
102	 *	    u unused, l large
103	 */
104	if (present) {
105		pteval = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
106		pteval |= _PAGE_LARGE | _PAGE_PRESENT;
107		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_READ, _PAGE_READ);
108		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE, _PAGE_WRITE);
109		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID, _PAGE_INVALID);
110		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT, _PAGE_PROTECT);
111		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY, _PAGE_DIRTY);
112		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG, _PAGE_YOUNG);
113#ifdef CONFIG_MEM_SOFT_DIRTY
114		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY, _PAGE_SOFT_DIRTY);
115#endif
116		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC, _PAGE_NOEXEC);
117	} else
118		pteval = _PAGE_INVALID;
119	return __pte(pteval);
120}
121
122static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
123{
124	struct page *page;
125	unsigned long size, paddr;
126
127	if (!mm_uses_skeys(mm) ||
128	    rste & _SEGMENT_ENTRY_INVALID)
129		return;
130
131	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
132		page = pud_page(__pud(rste));
133		size = PUD_SIZE;
134		paddr = rste & PUD_MASK;
135	} else {
136		page = pmd_page(__pmd(rste));
137		size = PMD_SIZE;
138		paddr = rste & PMD_MASK;
139	}
140
141	if (!test_and_set_bit(PG_arch_1, &page->flags))
142		__storage_key_init_range(paddr, paddr + size - 1);
143}
144
145void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
146		     pte_t *ptep, pte_t pte)
147{
148	unsigned long rste;
149
150	rste = __pte_to_rste(pte);
151	if (!MACHINE_HAS_NX)
152		rste &= ~_SEGMENT_ENTRY_NOEXEC;
153
154	/* Set correct table type for 2G hugepages */
155	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
156		if (likely(pte_present(pte)))
157			rste |= _REGION3_ENTRY_LARGE;
158		rste |= _REGION_ENTRY_TYPE_R3;
159	} else if (likely(pte_present(pte)))
160		rste |= _SEGMENT_ENTRY_LARGE;
161
162	clear_huge_pte_skeys(mm, rste);
163	set_pte(ptep, __pte(rste));
164}
165
166void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
167		     pte_t *ptep, pte_t pte, unsigned long sz)
168{
169	__set_huge_pte_at(mm, addr, ptep, pte);
170}
171
172pte_t huge_ptep_get(pte_t *ptep)
173{
174	return __rste_to_pte(pte_val(*ptep));
175}
176
177pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
178			      unsigned long addr, pte_t *ptep)
179{
180	pte_t pte = huge_ptep_get(ptep);
181	pmd_t *pmdp = (pmd_t *) ptep;
182	pud_t *pudp = (pud_t *) ptep;
183
184	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
185		pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
186	else
187		pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
188	return pte;
189}
190
191pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
192			unsigned long addr, unsigned long sz)
193{
194	pgd_t *pgdp;
195	p4d_t *p4dp;
196	pud_t *pudp;
197	pmd_t *pmdp = NULL;
198
199	pgdp = pgd_offset(mm, addr);
200	p4dp = p4d_alloc(mm, pgdp, addr);
201	if (p4dp) {
202		pudp = pud_alloc(mm, p4dp, addr);
203		if (pudp) {
204			if (sz == PUD_SIZE)
205				return (pte_t *) pudp;
206			else if (sz == PMD_SIZE)
207				pmdp = pmd_alloc(mm, pudp, addr);
208		}
209	}
210	return (pte_t *) pmdp;
211}
212
213pte_t *huge_pte_offset(struct mm_struct *mm,
214		       unsigned long addr, unsigned long sz)
215{
216	pgd_t *pgdp;
217	p4d_t *p4dp;
218	pud_t *pudp;
219	pmd_t *pmdp = NULL;
220
221	pgdp = pgd_offset(mm, addr);
222	if (pgd_present(*pgdp)) {
223		p4dp = p4d_offset(pgdp, addr);
224		if (p4d_present(*p4dp)) {
225			pudp = pud_offset(p4dp, addr);
226			if (pud_present(*pudp)) {
227				if (pud_large(*pudp))
228					return (pte_t *) pudp;
229				pmdp = pmd_offset(pudp, addr);
230			}
231		}
232	}
233	return (pte_t *) pmdp;
234}
235
236int pmd_huge(pmd_t pmd)
237{
238	return pmd_large(pmd);
239}
240
241int pud_huge(pud_t pud)
242{
243	return pud_large(pud);
244}
245
246bool __init arch_hugetlb_valid_size(unsigned long size)
247{
248	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
249		return true;
250	else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE)
251		return true;
252	else
253		return false;
254}
255
256static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
257		unsigned long addr, unsigned long len,
258		unsigned long pgoff, unsigned long flags)
259{
260	struct hstate *h = hstate_file(file);
261	struct vm_unmapped_area_info info;
262
263	info.flags = 0;
264	info.length = len;
265	info.low_limit = current->mm->mmap_base;
266	info.high_limit = TASK_SIZE;
267	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
268	info.align_offset = 0;
269	return vm_unmapped_area(&info);
270}
271
272static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
273		unsigned long addr0, unsigned long len,
274		unsigned long pgoff, unsigned long flags)
275{
276	struct hstate *h = hstate_file(file);
277	struct vm_unmapped_area_info info;
278	unsigned long addr;
279
280	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
281	info.length = len;
282	info.low_limit = PAGE_SIZE;
283	info.high_limit = current->mm->mmap_base;
284	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
285	info.align_offset = 0;
286	addr = vm_unmapped_area(&info);
287
288	/*
289	 * A failed mmap() very likely causes application failure,
290	 * so fall back to the bottom-up function here. This scenario
291	 * can happen with large stack limits and large mmap()
292	 * allocations.
293	 */
294	if (addr & ~PAGE_MASK) {
295		VM_BUG_ON(addr != -ENOMEM);
296		info.flags = 0;
297		info.low_limit = TASK_UNMAPPED_BASE;
298		info.high_limit = TASK_SIZE;
299		addr = vm_unmapped_area(&info);
300	}
301
302	return addr;
303}
304
305unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
306		unsigned long len, unsigned long pgoff, unsigned long flags)
307{
308	struct hstate *h = hstate_file(file);
309	struct mm_struct *mm = current->mm;
310	struct vm_area_struct *vma;
311
312	if (len & ~huge_page_mask(h))
313		return -EINVAL;
314	if (len > TASK_SIZE - mmap_min_addr)
315		return -ENOMEM;
316
317	if (flags & MAP_FIXED) {
318		if (prepare_hugepage_range(file, addr, len))
319			return -EINVAL;
320		goto check_asce_limit;
321	}
322
323	if (addr) {
324		addr = ALIGN(addr, huge_page_size(h));
325		vma = find_vma(mm, addr);
326		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
327		    (!vma || addr + len <= vm_start_gap(vma)))
328			goto check_asce_limit;
329	}
330
331	if (mm->get_unmapped_area == arch_get_unmapped_area)
332		addr = hugetlb_get_unmapped_area_bottomup(file, addr, len,
333				pgoff, flags);
334	else
335		addr = hugetlb_get_unmapped_area_topdown(file, addr, len,
336				pgoff, flags);
337	if (offset_in_page(addr))
338		return addr;
339
340check_asce_limit:
341	return check_asce_limit(mm, addr, len);
342}