[linux-2.6-block.git] / arch / s390 / mm / hugetlbpage.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  IBM System z Huge TLB Page Support for Kernel.
 *
 *    Copyright IBM Corp. 2007,2020
 *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
 */

#define KMSG_COMPONENT "hugetlb"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <asm/pgalloc.h>
#include <linux/mm.h>
#include <linux/hugetlb.h>
#include <linux/mman.h>
#include <linux/sched/mm.h>
#include <linux/security.h>

/*
 * If the bit selected by single-bit bitmask "a" is set within "x", move
 * it to the position indicated by single-bit bitmask "b".
 */
#define move_set_bit(x, a, b)	(((x) & (a)) >> ilog2(a) << ilog2(b))

static inline unsigned long __pte_to_rste(pte_t pte)
{
	unsigned long rste;

	/*
	 * Convert encoding		  pte bits	pmd / pud bits
	 *				lIR.uswrdy.p	dy..R...I...wr
	 * empty			010.000000.0 -> 00..0...1...00
	 * prot-none, clean, old	111.000000.1 -> 00..1...1...00
	 * prot-none, clean, young	111.000001.1 -> 01..1...1...00
	 * prot-none, dirty, old	111.000010.1 -> 10..1...1...00
	 * prot-none, dirty, young	111.000011.1 -> 11..1...1...00
	 * read-only, clean, old	111.000100.1 -> 00..1...1...01
	 * read-only, clean, young	101.000101.1 -> 01..1...0...01
	 * read-only, dirty, old	111.000110.1 -> 10..1...1...01
	 * read-only, dirty, young	101.000111.1 -> 11..1...0...01
	 * read-write, clean, old	111.001100.1 -> 00..1...1...11
	 * read-write, clean, young	101.001101.1 -> 01..1...0...11
	 * read-write, dirty, old	110.001110.1 -> 10..0...1...11
	 * read-write, dirty, young	100.001111.1 -> 11..0...0...11
	 * HW-bits: R read-only, I invalid
	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
	 *	    u unused, l large
	 */
	if (pte_present(pte)) {
		rste = pte_val(pte) & PAGE_MASK;
		rste |= move_set_bit(pte_val(pte), _PAGE_READ,
				     _SEGMENT_ENTRY_READ);
		rste |= move_set_bit(pte_val(pte), _PAGE_WRITE,
				     _SEGMENT_ENTRY_WRITE);
		rste |= move_set_bit(pte_val(pte), _PAGE_INVALID,
				     _SEGMENT_ENTRY_INVALID);
		rste |= move_set_bit(pte_val(pte), _PAGE_PROTECT,
				     _SEGMENT_ENTRY_PROTECT);
		rste |= move_set_bit(pte_val(pte), _PAGE_DIRTY,
				     _SEGMENT_ENTRY_DIRTY);
		rste |= move_set_bit(pte_val(pte), _PAGE_YOUNG,
				     _SEGMENT_ENTRY_YOUNG);
#ifdef CONFIG_MEM_SOFT_DIRTY
		rste |= move_set_bit(pte_val(pte), _PAGE_SOFT_DIRTY,
				     _SEGMENT_ENTRY_SOFT_DIRTY);
#endif
		rste |= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
				     _SEGMENT_ENTRY_NOEXEC);
	} else
		rste = _SEGMENT_ENTRY_EMPTY;
	return rste;
}

static inline pte_t __rste_to_pte(unsigned long rste)
{
	unsigned long pteval;
	int present;

	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
		present = pud_present(__pud(rste));
	else
		present = pmd_present(__pmd(rste));

	/*
	 * Convert encoding		pmd / pud bits	    pte bits
	 *				dy..R...I...wr	  lIR.uswrdy.p
	 * empty			00..0...1...00 -> 010.000000.0
	 * prot-none, clean, old	00..1...1...00 -> 111.000000.1
	 * prot-none, clean, young	01..1...1...00 -> 111.000001.1
	 * prot-none, dirty, old	10..1...1...00 -> 111.000010.1
	 * prot-none, dirty, young	11..1...1...00 -> 111.000011.1
	 * read-only, clean, old	00..1...1...01 -> 111.000100.1
	 * read-only, clean, young	01..1...0...01 -> 101.000101.1
	 * read-only, dirty, old	10..1...1...01 -> 111.000110.1
	 * read-only, dirty, young	11..1...0...01 -> 101.000111.1
	 * read-write, clean, old	00..1...1...11 -> 111.001100.1
	 * read-write, clean, young	01..1...0...11 -> 101.001101.1
	 * read-write, dirty, old	10..0...1...11 -> 110.001110.1
	 * read-write, dirty, young	11..0...0...11 -> 100.001111.1
	 * HW-bits: R read-only, I invalid
	 * SW-bits: p present, y young, d dirty, r read, w write, s special,
	 *	    u unused, l large
	 */
	if (present) {
		pteval = rste & _SEGMENT_ENTRY_ORIGIN_LARGE;
		pteval |= _PAGE_LARGE | _PAGE_PRESENT;
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_READ, _PAGE_READ);
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_WRITE, _PAGE_WRITE);
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_INVALID, _PAGE_INVALID);
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_PROTECT, _PAGE_PROTECT);
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_DIRTY, _PAGE_DIRTY);
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_YOUNG, _PAGE_YOUNG);
#ifdef CONFIG_MEM_SOFT_DIRTY
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY, _PAGE_SOFT_DIRTY);
#endif
		pteval |= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC, _PAGE_NOEXEC);
	} else
		pteval = _PAGE_INVALID;
	return __pte(pteval);
}

static void clear_huge_pte_skeys(struct mm_struct *mm, unsigned long rste)
{
	struct page *page;
	unsigned long size, paddr;

	if (!mm_uses_skeys(mm) ||
	    rste & _SEGMENT_ENTRY_INVALID)
		return;

	if ((rste & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
		page = pud_page(__pud(rste));
		size = PUD_SIZE;
		paddr = rste & PUD_MASK;
	} else {
		page = pmd_page(__pmd(rste));
		size = PMD_SIZE;
		paddr = rste & PMD_MASK;
	}

	if (!test_and_set_bit(PG_arch_1, &page->flags))
		__storage_key_init_range(paddr, paddr + size);
}

void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
		     pte_t *ptep, pte_t pte)
{
	unsigned long rste;

	rste = __pte_to_rste(pte);
	if (!MACHINE_HAS_NX)
		rste &= ~_SEGMENT_ENTRY_NOEXEC;

	/* Set correct table type for 2G hugepages */
	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3) {
		if (likely(pte_present(pte)))
			rste |= _REGION3_ENTRY_LARGE;
		rste |= _REGION_ENTRY_TYPE_R3;
	} else if (likely(pte_present(pte)))
		rste |= _SEGMENT_ENTRY_LARGE;

	clear_huge_pte_skeys(mm, rste);
	set_pte(ptep, __pte(rste));
}

void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
		     pte_t *ptep, pte_t pte, unsigned long sz)
{
	__set_huge_pte_at(mm, addr, ptep, pte);
}

pte_t huge_ptep_get(pte_t *ptep)
{
	return __rste_to_pte(pte_val(*ptep));
}

pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
			      unsigned long addr, pte_t *ptep)
{
	pte_t pte = huge_ptep_get(ptep);
	pmd_t *pmdp = (pmd_t *) ptep;
	pud_t *pudp = (pud_t *) ptep;

	if ((pte_val(*ptep) & _REGION_ENTRY_TYPE_MASK) == _REGION_ENTRY_TYPE_R3)
		pudp_xchg_direct(mm, addr, pudp, __pud(_REGION3_ENTRY_EMPTY));
	else
		pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
	return pte;
}

pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma,
			unsigned long addr, unsigned long sz)
{
	pgd_t *pgdp;
	p4d_t *p4dp;
	pud_t *pudp;
	pmd_t *pmdp = NULL;

	pgdp = pgd_offset(mm, addr);
	p4dp = p4d_alloc(mm, pgdp, addr);
	if (p4dp) {
		pudp = pud_alloc(mm, p4dp, addr);
		if (pudp) {
			if (sz == PUD_SIZE)
				return (pte_t *) pudp;
			else if (sz == PMD_SIZE)
				pmdp = pmd_alloc(mm, pudp, addr);
		}
	}
	return (pte_t *) pmdp;
}

pte_t *huge_pte_offset(struct mm_struct *mm,
		       unsigned long addr, unsigned long sz)
{
	pgd_t *pgdp;
	p4d_t *p4dp;
	pud_t *pudp;
	pmd_t *pmdp = NULL;

	pgdp = pgd_offset(mm, addr);
	if (pgd_present(*pgdp)) {
		p4dp = p4d_offset(pgdp, addr);
		if (p4d_present(*p4dp)) {
			pudp = pud_offset(p4dp, addr);
			if (pud_present(*pudp)) {
				if (pud_leaf(*pudp))
					return (pte_t *) pudp;
				pmdp = pmd_offset(pudp, addr);
			}
		}
	}
	return (pte_t *) pmdp;
}

bool __init arch_hugetlb_valid_size(unsigned long size)
{
	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
		return true;
	else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE)
		return true;
	else
		return false;
}

static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
		unsigned long addr, unsigned long len,
		unsigned long pgoff, unsigned long flags)
{
	struct hstate *h = hstate_file(file);
	struct vm_unmapped_area_info info = {};

	info.length = len;
	info.low_limit = current->mm->mmap_base;
	info.high_limit = TASK_SIZE;
	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
	return vm_unmapped_area(&info);
}

static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
		unsigned long addr0, unsigned long len,
		unsigned long pgoff, unsigned long flags)
{
	struct hstate *h = hstate_file(file);
	struct vm_unmapped_area_info info = {};
	unsigned long addr;

	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
	info.length = len;
	info.low_limit = PAGE_SIZE;
	info.high_limit = current->mm->mmap_base;
	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
	addr = vm_unmapped_area(&info);

	/*
	 * A failed mmap() very likely causes application failure,
	 * so fall back to the bottom-up function here. This scenario
	 * can happen with large stack limits and large mmap()
	 * allocations.
	 */
	if (addr & ~PAGE_MASK) {
		VM_BUG_ON(addr != -ENOMEM);
		info.flags = 0;
		info.low_limit = TASK_UNMAPPED_BASE;
		info.high_limit = TASK_SIZE;
		addr = vm_unmapped_area(&info);
	}

	return addr;
}

unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
		unsigned long len, unsigned long pgoff, unsigned long flags)
{
	struct hstate *h = hstate_file(file);
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;

	if (len & ~huge_page_mask(h))
		return -EINVAL;
	if (len > TASK_SIZE - mmap_min_addr)
		return -ENOMEM;

	if (flags & MAP_FIXED) {
		if (prepare_hugepage_range(file, addr, len))
			return -EINVAL;
		goto check_asce_limit;
	}

	if (addr) {
		addr = ALIGN(addr, huge_page_size(h));
		vma = find_vma(mm, addr);
		if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
		    (!vma || addr + len <= vm_start_gap(vma)))
			goto check_asce_limit;
	}

	if (!test_bit(MMF_TOPDOWN, &mm->flags))
		addr = hugetlb_get_unmapped_area_bottomup(file, addr, len,
				pgoff, flags);
	else
		addr = hugetlb_get_unmapped_area_topdown(file, addr, len,
				pgoff, flags);
	if (offset_in_page(addr))
		return addr;

check_asce_limit:
	return check_asce_limit(mm, addr, len);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
53492b1d GS	2	/*
	3	* IBM System z Huge TLB Page Support for Kernel.
	4	*
5f490a52	5	* Copyright IBM Corp. 2007,2020
53492b1d GS	6	* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
	7	*/
	8
d08de8e2 GS	9	#define KMSG_COMPONENT "hugetlb"
	10	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
	11
f7ea534a	12	#include <asm/pgalloc.h>
53492b1d GS	13	#include <linux/mm.h>
53492b1d GS	14	#include <linux/hugetlb.h>
5f490a52 GS	15	#include <linux/mman.h>
	16	#include <linux/sched/mm.h>
	17	#include <linux/security.h>
53492b1d	18
bc29b7ac GS	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
d08de8e2	25	static inline unsigned long __pte_to_rste(pte_t pte)
e5098611	26	{
d08de8e2	27	unsigned long rste;
e5098611 MS	28
e5098611 MS	29	/*
d08de8e2	30	* Convert encoding pte bits pmd / pud bits
a1c843b8 MS	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
e5098611 MS	48	*/
e5098611 MS	49	if (pte_present(pte)) {
d08de8e2	50	rste = pte_val(pte) & PAGE_MASK;
bc29b7ac GS	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
57d7f939 MS	67	rste \|= move_set_bit(pte_val(pte), _PAGE_NOEXEC,
57d7f939 MS	68	_SEGMENT_ENTRY_NOEXEC);
e5098611	69	} else
54397bb0	70	rste = _SEGMENT_ENTRY_EMPTY;
d08de8e2	71	return rste;
e5098611 MS	72	}
e5098611 MS	73
d08de8e2	74	static inline pte_t __rste_to_pte(unsigned long rste)
e5098611	75	{
933b7253	76	unsigned long pteval;
d08de8e2	77	int present;
e5098611	78
d08de8e2 GS	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
e5098611	84	/*
d08de8e2	85	* Convert encoding pmd / pud bits pte bits
a1c843b8 MS	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
e5098611	103	*/
d08de8e2	104	if (present) {
933b7253 HC	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);
bc29b7ac	113	#ifdef CONFIG_MEM_SOFT_DIRTY
933b7253	114	pteval \|= move_set_bit(rste, _SEGMENT_ENTRY_SOFT_DIRTY, _PAGE_SOFT_DIRTY);
bc29b7ac	115	#endif
933b7253	116	pteval \|= move_set_bit(rste, _SEGMENT_ENTRY_NOEXEC, _PAGE_NOEXEC);
e5098611	117	} else
933b7253 HC	118	pteval = _PAGE_INVALID;
933b7253 HC	119	return __pte(pteval);
e5098611	120	}
53492b1d	121
3afdfca6 JF	122	static 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))
412050af	142	__storage_key_init_range(paddr, paddr + size);
3afdfca6 JF	143	}
3afdfca6 JF	144
935d4f0c	145	void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
e5098611	146	pte_t *ptep, pte_t pte)
53492b1d	147	{
57d7f939 MS	148	unsigned long rste;
	149
	150	rste = __pte_to_rste(pte);
	151	if (!MACHINE_HAS_NX)
	152	rste &= ~_SEGMENT_ENTRY_NOEXEC;
d08de8e2 GS	153
d08de8e2 GS	154	/* Set correct table type for 2G hugepages */
ac8372f3 GS	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)))
d08de8e2	160	rste \|= _SEGMENT_ENTRY_LARGE;
ac8372f3	161
3afdfca6	162	clear_huge_pte_skeys(mm, rste);
b8e3b379	163	set_pte(ptep, __pte(rste));
e5098611 MS	164	}
e5098611 MS	165
935d4f0c RR	166	void 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
e5098611 MS	172	pte_t huge_ptep_get(pte_t *ptep)
e5098611 MS	173	{
d08de8e2	174	return __rste_to_pte(pte_val(*ptep));
e5098611 MS	175	}
	176
	177	pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
	178	unsigned long addr, pte_t *ptep)
	179	{
d08de8e2	180	pte_t pte = huge_ptep_get(ptep);
e5098611	181	pmd_t pmdp = (pmd_t ) ptep;
d08de8e2	182	pud_t pudp = (pud_t ) ptep;
53492b1d	183
d08de8e2 GS	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;
53492b1d GS	189	}
53492b1d GS	190
aec44e0f	191	pte_t huge_pte_alloc(struct mm_struct mm, struct vm_area_struct *vma,
a5516438	192	unsigned long addr, unsigned long sz)
53492b1d GS	193	{
53492b1d GS	194	pgd_t *pgdp;
1aea9b3f	195	p4d_t *p4dp;
53492b1d GS	196	pud_t *pudp;
	197	pmd_t *pmdp = NULL;
	198
	199	pgdp = pgd_offset(mm, addr);
1aea9b3f MS	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	}
d08de8e2	209	}
53492b1d GS	210	return (pte_t *) pmdp;
	211	}
	212
7868a208 PA	213	pte_t huge_pte_offset(struct mm_struct mm,
7868a208 PA	214	unsigned long addr, unsigned long sz)
53492b1d GS	215	{
53492b1d GS	216	pgd_t *pgdp;
1aea9b3f	217	p4d_t *p4dp;
53492b1d GS	218	pud_t *pudp;
	219	pmd_t *pmdp = NULL;
	220
	221	pgdp = pgd_offset(mm, addr);
	222	if (pgd_present(*pgdp)) {
1aea9b3f MS	223	p4dp = p4d_offset(pgdp, addr);
	224	if (p4d_present(*p4dp)) {
	225	pudp = pud_offset(p4dp, addr);
	226	if (pud_present(*pudp)) {
0a845e0f	227	if (pud_leaf(*pudp))
1aea9b3f MS	228	return (pte_t *) pudp;
	229	pmdp = pmd_offset(pudp, addr);
	230	}
d08de8e2	231	}
53492b1d GS	232	}
	233	return (pte_t *) pmdp;
	234	}
	235
ae94da89 MK	236	bool __init arch_hugetlb_valid_size(unsigned long size)
	237	{
	238	if (MACHINE_HAS_EDAT1 && size == PMD_SIZE)
	239	return true;
	240	else if (MACHINE_HAS_EDAT2 && size == PUD_SIZE)
	241	return true;
	242	else
	243	return false;
	244	}
	245
5f490a52 GS	246	static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
	247	unsigned long addr, unsigned long len,
	248	unsigned long pgoff, unsigned long flags)
	249	{
	250	struct hstate *h = hstate_file(file);
b80fa3cb	251	struct vm_unmapped_area_info info = {};
5f490a52	252
5f490a52 GS	253	info.length = len;
	254	info.low_limit = current->mm->mmap_base;
	255	info.high_limit = TASK_SIZE;
	256	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
5f490a52 GS	257	return vm_unmapped_area(&info);
	258	}
	259
	260	static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
	261	unsigned long addr0, unsigned long len,
	262	unsigned long pgoff, unsigned long flags)
	263	{
	264	struct hstate *h = hstate_file(file);
b80fa3cb	265	struct vm_unmapped_area_info info = {};
5f490a52 GS	266	unsigned long addr;
	267
	268	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
	269	info.length = len;
6b008640	270	info.low_limit = PAGE_SIZE;
5f490a52 GS	271	info.high_limit = current->mm->mmap_base;
5f490a52 GS	272	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
5f490a52 GS	273	addr = vm_unmapped_area(&info);
	274
	275	/*
	276	* A failed mmap() very likely causes application failure,
	277	* so fall back to the bottom-up function here. This scenario
	278	* can happen with large stack limits and large mmap()
	279	* allocations.
	280	*/
	281	if (addr & ~PAGE_MASK) {
	282	VM_BUG_ON(addr != -ENOMEM);
	283	info.flags = 0;
	284	info.low_limit = TASK_UNMAPPED_BASE;
	285	info.high_limit = TASK_SIZE;
	286	addr = vm_unmapped_area(&info);
	287	}
	288
	289	return addr;
	290	}
	291
	292	unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
	293	unsigned long len, unsigned long pgoff, unsigned long flags)
	294	{
	295	struct hstate *h = hstate_file(file);
	296	struct mm_struct *mm = current->mm;
	297	struct vm_area_struct *vma;
5f490a52 GS	298
	299	if (len & ~huge_page_mask(h))
	300	return -EINVAL;
	301	if (len > TASK_SIZE - mmap_min_addr)
	302	return -ENOMEM;
	303
	304	if (flags & MAP_FIXED) {
	305	if (prepare_hugepage_range(file, addr, len))
	306	return -EINVAL;
	307	goto check_asce_limit;
	308	}
	309
	310	if (addr) {
	311	addr = ALIGN(addr, huge_page_size(h));
	312	vma = find_vma(mm, addr);
	313	if (TASK_SIZE - len >= addr && addr >= mmap_min_addr &&
	314	(!vma \|\| addr + len <= vm_start_gap(vma)))
	315	goto check_asce_limit;
	316	}
	317
529ce23a	318	if (!test_bit(MMF_TOPDOWN, &mm->flags))
5f490a52 GS	319	addr = hugetlb_get_unmapped_area_bottomup(file, addr, len,
	320	pgoff, flags);
	321	else
	322	addr = hugetlb_get_unmapped_area_topdown(file, addr, len,
	323	pgoff, flags);
712fa5f2	324	if (offset_in_page(addr))
5f490a52 GS	325	return addr;
	326
	327	check_asce_limit:
712fa5f2	328	return check_asce_limit(mm, addr, len);
5f490a52	329	}