[deliverable/linux.git] / arch / s390 / mm / hugetlbpage.c

/*
 *  IBM System z Huge TLB Page Support for Kernel.
 *
 *    Copyright IBM Corp. 2007
 *    Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
 */

#include <linux/mm.h>
#include <linux/hugetlb.h>

static inline pmd_t __pte_to_pmd(pte_t pte)
{
	pmd_t pmd;

	/*
	 * Convert encoding		  pte bits	   pmd 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)) {
		pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_READ) >> 4;
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_WRITE) >> 4;
		pmd_val(pmd) |=	(pte_val(pte) & _PAGE_INVALID) >> 5;
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_PROTECT);
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_DIRTY) << 10;
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_YOUNG) << 10;
		pmd_val(pmd) |= (pte_val(pte) & _PAGE_SOFT_DIRTY) << 13;
	} else
		pmd_val(pmd) = _SEGMENT_ENTRY_INVALID;
	return pmd;
}

static inline pte_t __pmd_to_pte(pmd_t pmd)
{
	pte_t pte;

	/*
	 * Convert encoding		   pmd 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 (pmd_present(pmd)) {
		pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;
		pte_val(pte) |= _PAGE_LARGE | _PAGE_PRESENT;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_READ) << 4;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) << 4;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) << 5;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT);
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) >> 10;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) >> 10;
		pte_val(pte) |= (pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY) >> 13;
	} else
		pte_val(pte) = _PAGE_INVALID;
	return pte;
}

void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
		     pte_t *ptep, pte_t pte)
{
	pmd_t pmd = __pte_to_pmd(pte);

	pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
	*(pmd_t *) ptep = pmd;
}

pte_t huge_ptep_get(pte_t *ptep)
{
	pmd_t pmd = *(pmd_t *) ptep;

	return __pmd_to_pte(pmd);
}

pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
			      unsigned long addr, pte_t *ptep)
{
	pmd_t *pmdp = (pmd_t *) ptep;
	pmd_t old;

	old = pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
	return __pmd_to_pte(old);
}

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

	pgdp = pgd_offset(mm, addr);
	pudp = pud_alloc(mm, pgdp, addr);
	if (pudp)
		pmdp = pmd_alloc(mm, pudp, addr);
	return (pte_t *) pmdp;
}

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

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

int pmd_huge(pmd_t pmd)
{
	return pmd_large(pmd);
}

int pud_huge(pud_t pud)
{
	return 0;
}
Commit	Line	Data
53492b1d GS	1	/*
	2	* IBM System z Huge TLB Page Support for Kernel.
	3	*
a53c8fab	4	* Copyright IBM Corp. 2007
53492b1d GS	5	* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
	6	*/
	7
	8	#include <linux/mm.h>
	9	#include <linux/hugetlb.h>
	10
e5098611 MS	11	static inline pmd_t __pte_to_pmd(pte_t pte)
e5098611 MS	12	{
e5098611 MS	13	pmd_t pmd;
	14
	15	/*
152125b7	16	* Convert encoding pte bits pmd bits
a1c843b8 MS	17	* lIR.uswrdy.p dy..R...I...wr
	18	* empty 010.000000.0 -> 00..0...1...00
	19	* prot-none, clean, old 111.000000.1 -> 00..1...1...00
	20	* prot-none, clean, young 111.000001.1 -> 01..1...1...00
	21	* prot-none, dirty, old 111.000010.1 -> 10..1...1...00
	22	* prot-none, dirty, young 111.000011.1 -> 11..1...1...00
	23	* read-only, clean, old 111.000100.1 -> 00..1...1...01
	24	* read-only, clean, young 101.000101.1 -> 01..1...0...01
	25	* read-only, dirty, old 111.000110.1 -> 10..1...1...01
	26	* read-only, dirty, young 101.000111.1 -> 11..1...0...01
	27	* read-write, clean, old 111.001100.1 -> 00..1...1...11
	28	* read-write, clean, young 101.001101.1 -> 01..1...0...11
	29	* read-write, dirty, old 110.001110.1 -> 10..0...1...11
	30	* read-write, dirty, young 100.001111.1 -> 11..0...0...11
	31	* HW-bits: R read-only, I invalid
	32	* SW-bits: p present, y young, d dirty, r read, w write, s special,
	33	* u unused, l large
e5098611 MS	34	*/
	35	if (pte_present(pte)) {
	36	pmd_val(pmd) = pte_val(pte) & PAGE_MASK;
152125b7 MS	37	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_READ) >> 4;
	38	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_WRITE) >> 4;
	39	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_INVALID) >> 5;
	40	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_PROTECT);
	41	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_DIRTY) << 10;
	42	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_YOUNG) << 10;
5614dd92	43	pmd_val(pmd) \|= (pte_val(pte) & _PAGE_SOFT_DIRTY) << 13;
e5098611 MS	44	} else
	45	pmd_val(pmd) = _SEGMENT_ENTRY_INVALID;
	46	return pmd;
	47	}
	48
	49	static inline pte_t __pmd_to_pte(pmd_t pmd)
	50	{
	51	pte_t pte;
	52
	53	/*
152125b7	54	* Convert encoding pmd bits pte bits
a1c843b8 MS	55	* dy..R...I...wr lIR.uswrdy.p
	56	* empty 00..0...1...00 -> 010.000000.0
	57	* prot-none, clean, old 00..1...1...00 -> 111.000000.1
	58	* prot-none, clean, young 01..1...1...00 -> 111.000001.1
	59	* prot-none, dirty, old 10..1...1...00 -> 111.000010.1
	60	* prot-none, dirty, young 11..1...1...00 -> 111.000011.1
	61	* read-only, clean, old 00..1...1...01 -> 111.000100.1
	62	* read-only, clean, young 01..1...0...01 -> 101.000101.1
	63	* read-only, dirty, old 10..1...1...01 -> 111.000110.1
	64	* read-only, dirty, young 11..1...0...01 -> 101.000111.1
	65	* read-write, clean, old 00..1...1...11 -> 111.001100.1
	66	* read-write, clean, young 01..1...0...11 -> 101.001101.1
	67	* read-write, dirty, old 10..0...1...11 -> 110.001110.1
	68	* read-write, dirty, young 11..0...0...11 -> 100.001111.1
	69	* HW-bits: R read-only, I invalid
	70	* SW-bits: p present, y young, d dirty, r read, w write, s special,
	71	* u unused, l large
e5098611 MS	72	*/
e5098611 MS	73	if (pmd_present(pmd)) {
152125b7 MS	74	pte_val(pte) = pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN_LARGE;
	75	pte_val(pte) \|= _PAGE_LARGE \| _PAGE_PRESENT;
	76	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_READ) << 4;
	77	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_WRITE) << 4;
	78	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_INVALID) << 5;
	79	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_PROTECT);
b7d14f3a MS	80	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_DIRTY) >> 10;
b7d14f3a MS	81	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_YOUNG) >> 10;
5614dd92	82	pte_val(pte) \|= (pmd_val(pmd) & _SEGMENT_ENTRY_SOFT_DIRTY) >> 13;
e5098611 MS	83	} else
	84	pte_val(pte) = _PAGE_INVALID;
	85	return pte;
	86	}
53492b1d GS	87
53492b1d GS	88	void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
e5098611	89	pte_t *ptep, pte_t pte)
53492b1d	90	{
ce415712	91	pmd_t pmd = __pte_to_pmd(pte);
53492b1d	92
ce415712	93	pmd_val(pmd) \|= _SEGMENT_ENTRY_LARGE;
e5098611 MS	94	(pmd_t ) ptep = pmd;
	95	}
	96
	97	pte_t huge_ptep_get(pte_t *ptep)
	98	{
ce415712	99	pmd_t pmd = (pmd_t ) ptep;
e5098611	100
e5098611 MS	101	return __pmd_to_pte(pmd);
	102	}
	103
	104	pte_t huge_ptep_get_and_clear(struct mm_struct *mm,
	105	unsigned long addr, pte_t *ptep)
	106	{
	107	pmd_t pmdp = (pmd_t ) ptep;
227be799	108	pmd_t old;
53492b1d	109
227be799 MS	110	old = pmdp_xchg_direct(mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY));
227be799 MS	111	return __pmd_to_pte(old);
53492b1d GS	112	}
53492b1d GS	113
a5516438 AK	114	pte_t huge_pte_alloc(struct mm_struct mm,
a5516438 AK	115	unsigned long addr, unsigned long sz)
53492b1d GS	116	{
	117	pgd_t *pgdp;
	118	pud_t *pudp;
	119	pmd_t *pmdp = NULL;
	120
	121	pgdp = pgd_offset(mm, addr);
	122	pudp = pud_alloc(mm, pgdp, addr);
	123	if (pudp)
	124	pmdp = pmd_alloc(mm, pudp, addr);
	125	return (pte_t *) pmdp;
	126	}
	127
	128	pte_t huge_pte_offset(struct mm_struct mm, unsigned long addr)
	129	{
	130	pgd_t *pgdp;
	131	pud_t *pudp;
	132	pmd_t *pmdp = NULL;
	133
	134	pgdp = pgd_offset(mm, addr);
	135	if (pgd_present(*pgdp)) {
	136	pudp = pud_offset(pgdp, addr);
	137	if (pud_present(*pudp))
	138	pmdp = pmd_offset(pudp, addr);
	139	}
	140	return (pte_t *) pmdp;
	141	}
	142
53492b1d GS	143	int pmd_huge(pmd_t pmd)
53492b1d GS	144	{
cbd7d9c2	145	return pmd_large(pmd);
53492b1d GS	146	}
53492b1d GS	147
ceb86879 AK	148	int pud_huge(pud_t pud)
	149	{
	150	return 0;
	151	}