[deliverable/linux.git] / include / asm-x86 / xen / page.h

#ifndef __XEN_PAGE_H
#define __XEN_PAGE_H

#include <linux/pfn.h>

#include <asm/uaccess.h>
#include <asm/pgtable.h>

#include <xen/features.h>

/* Xen machine address */
typedef struct xmaddr {
	phys_addr_t maddr;
} xmaddr_t;

/* Xen pseudo-physical address */
typedef struct xpaddr {
	phys_addr_t paddr;
} xpaddr_t;

#define XMADDR(x)	((xmaddr_t) { .maddr = (x) })
#define XPADDR(x)	((xpaddr_t) { .paddr = (x) })

/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/
#define INVALID_P2M_ENTRY	(~0UL)
#define FOREIGN_FRAME_BIT	(1UL<<31)
#define FOREIGN_FRAME(m)	((m) | FOREIGN_FRAME_BIT)

extern unsigned long *phys_to_machine_mapping;

static inline unsigned long pfn_to_mfn(unsigned long pfn)
{
	if (xen_feature(XENFEAT_auto_translated_physmap))
		return pfn;

	return phys_to_machine_mapping[(unsigned int)(pfn)] &
		~FOREIGN_FRAME_BIT;
}

static inline int phys_to_machine_mapping_valid(unsigned long pfn)
{
	if (xen_feature(XENFEAT_auto_translated_physmap))
		return 1;

	return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
}

static inline unsigned long mfn_to_pfn(unsigned long mfn)
{
	unsigned long pfn;

	if (xen_feature(XENFEAT_auto_translated_physmap))
		return mfn;

#if 0
	if (unlikely((mfn >> machine_to_phys_order) != 0))
		return max_mapnr;
#endif

	pfn = 0;
	/*
	 * The array access can fail (e.g., device space beyond end of RAM).
	 * In such cases it doesn't matter what we return (we return garbage),
	 * but we must handle the fault without crashing!
	 */
	__get_user(pfn, &machine_to_phys_mapping[mfn]);

	return pfn;
}

static inline xmaddr_t phys_to_machine(xpaddr_t phys)
{
	unsigned offset = phys.paddr & ~PAGE_MASK;
	return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
}

static inline xpaddr_t machine_to_phys(xmaddr_t machine)
{
	unsigned offset = machine.maddr & ~PAGE_MASK;
	return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
}

/*
 * We detect special mappings in one of two ways:
 *  1. If the MFN is an I/O page then Xen will set the m2p entry
 *     to be outside our maximum possible pseudophys range.
 *  2. If the MFN belongs to a different domain then we will certainly
 *     not have MFN in our p2m table. Conversely, if the page is ours,
 *     then we'll have p2m(m2p(MFN))==MFN.
 * If we detect a special mapping then it doesn't have a 'struct page'.
 * We force !pfn_valid() by returning an out-of-range pointer.
 *
 * NB. These checks require that, for any MFN that is not in our reservation,
 * there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
 * we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
 * Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
 *
 * NB2. When deliberately mapping foreign pages into the p2m table, you *must*
 *      use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
 *      require. In all the cases we care about, the FOREIGN_FRAME bit is
 *      masked (e.g., pfn_to_mfn()) so behaviour there is correct.
 */
static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
{
	extern unsigned long max_mapnr;
	unsigned long pfn = mfn_to_pfn(mfn);
	if ((pfn < max_mapnr)
	    && !xen_feature(XENFEAT_auto_translated_physmap)
	    && (phys_to_machine_mapping[pfn] != mfn))
		return max_mapnr; /* force !pfn_valid() */
	return pfn;
}

static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
{
	if (xen_feature(XENFEAT_auto_translated_physmap)) {
		BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
		return;
	}
	phys_to_machine_mapping[pfn] = mfn;
}

/* VIRT <-> MACHINE conversion */
#define virt_to_machine(v)	(phys_to_machine(XPADDR(__pa(v))))
#define virt_to_mfn(v)		(pfn_to_mfn(PFN_DOWN(__pa(v))))
#define mfn_to_virt(m)		(__va(mfn_to_pfn(m) << PAGE_SHIFT))

static inline unsigned long pte_mfn(pte_t pte)
{
	return (pte.pte & PTE_MASK) >> PAGE_SHIFT;
}

static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
{
	pte_t pte;

	pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) |
		(pgprot_val(pgprot) & __supported_pte_mask);

	return pte;
}

static inline pteval_t pte_val_ma(pte_t pte)
{
	return pte.pte;
}

static inline pte_t __pte_ma(pteval_t x)
{
	return (pte_t) { .pte = x };
}

#define pmd_val_ma(v) ((v).pmd)
#define pud_val_ma(v) ((v).pgd.pgd)
#define __pmd_ma(x)	((pmd_t) { (x) } )

#define pgd_val_ma(x)	((x).pgd)


xmaddr_t arbitrary_virt_to_machine(unsigned long address);
void make_lowmem_page_readonly(void *vaddr);
void make_lowmem_page_readwrite(void *vaddr);

#endif /* __XEN_PAGE_H */
Commit	Line	Data
20e71f2e IY	1	#ifndef __XEN_PAGE_H
	2	#define __XEN_PAGE_H
	3
	4	#include <linux/pfn.h>
	5
	6	#include <asm/uaccess.h>
	7	#include <asm/pgtable.h>
	8
	9	#include <xen/features.h>
	10
	11	/* Xen machine address */
	12	typedef struct xmaddr {
	13	phys_addr_t maddr;
	14	} xmaddr_t;
	15
	16	/* Xen pseudo-physical address */
	17	typedef struct xpaddr {
	18	phys_addr_t paddr;
	19	} xpaddr_t;
	20
	21	#define XMADDR(x) ((xmaddr_t) { .maddr = (x) })
	22	#define XPADDR(x) ((xpaddr_t) { .paddr = (x) })
	23
	24	/** MACHINE <-> PHYSICAL CONVERSION MACROS **/
	25	#define INVALID_P2M_ENTRY (~0UL)
	26	#define FOREIGN_FRAME_BIT (1UL<<31)
	27	#define FOREIGN_FRAME(m) ((m) \| FOREIGN_FRAME_BIT)
	28
	29	extern unsigned long *phys_to_machine_mapping;
	30
	31	static inline unsigned long pfn_to_mfn(unsigned long pfn)
	32	{
	33	if (xen_feature(XENFEAT_auto_translated_physmap))
	34	return pfn;
	35
	36	return phys_to_machine_mapping[(unsigned int)(pfn)] &
	37	~FOREIGN_FRAME_BIT;
	38	}
	39
	40	static inline int phys_to_machine_mapping_valid(unsigned long pfn)
	41	{
	42	if (xen_feature(XENFEAT_auto_translated_physmap))
	43	return 1;
	44
	45	return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY);
	46	}
	47
	48	static inline unsigned long mfn_to_pfn(unsigned long mfn)
	49	{
	50	unsigned long pfn;
	51
	52	if (xen_feature(XENFEAT_auto_translated_physmap))
	53	return mfn;
	54
	55	#if 0
	56	if (unlikely((mfn >> machine_to_phys_order) != 0))
	57	return max_mapnr;
	58	#endif
	59
	60	pfn = 0;
	61	/*
	62	* The array access can fail (e.g., device space beyond end of RAM).
	63	* In such cases it doesn't matter what we return (we return garbage),
	64	* but we must handle the fault without crashing!
65	*/
66	__get_user(pfn, &machine_to_phys_mapping[mfn]);
67
68	return pfn;
69	}
70
71	static inline xmaddr_t phys_to_machine(xpaddr_t phys)
72	{
73	unsigned offset = phys.paddr & ~PAGE_MASK;
74	return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) \| offset);
75	}
76
77	static inline xpaddr_t machine_to_phys(xmaddr_t machine)
78	{
79	unsigned offset = machine.maddr & ~PAGE_MASK;
80	return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) \| offset);
81	}
82
83	/*
84	* We detect special mappings in one of two ways:
85	* 1. If the MFN is an I/O page then Xen will set the m2p entry
86	* to be outside our maximum possible pseudophys range.
87	* 2. If the MFN belongs to a different domain then we will certainly
88	* not have MFN in our p2m table. Conversely, if the page is ours,
89	* then we'll have p2m(m2p(MFN))==MFN.
90	* If we detect a special mapping then it doesn't have a 'struct page'.
91	* We force !pfn_valid() by returning an out-of-range pointer.
92	*
93	* NB. These checks require that, for any MFN that is not in our reservation,
94	* there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if
95	* we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN.
96	* Yikes! Various places must poke in INVALID_P2M_ENTRY for safety.
97	*
98	* NB2. When deliberately mapping foreign pages into the p2m table, you must
99	* use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we
100	* require. In all the cases we care about, the FOREIGN_FRAME bit is
101	* masked (e.g., pfn_to_mfn()) so behaviour there is correct.
102	*/
103	static inline unsigned long mfn_to_local_pfn(unsigned long mfn)
104	{
105	extern unsigned long max_mapnr;
106	unsigned long pfn = mfn_to_pfn(mfn);
107	if ((pfn < max_mapnr)
108	&& !xen_feature(XENFEAT_auto_translated_physmap)
109	&& (phys_to_machine_mapping[pfn] != mfn))
110	return max_mapnr; /* force !pfn_valid() */
111	return pfn;
112	}
113
114	static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn)
115	{
116	if (xen_feature(XENFEAT_auto_translated_physmap)) {
117	BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
118	return;
119	}
120	phys_to_machine_mapping[pfn] = mfn;
121	}
122
123	/* VIRT <-> MACHINE conversion */
124	#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
125	#define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v))))
126	#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
127
128	static inline unsigned long pte_mfn(pte_t pte)
129	{
cbb3077c	130	return (pte.pte & PTE_MASK) >> PAGE_SHIFT;
20e71f2e IY	131	}
	132
	133	static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot)
	134	{
	135	pte_t pte;
	136
	137	pte.pte = ((phys_addr_t)page_nr << PAGE_SHIFT) \|
	138	(pgprot_val(pgprot) & __supported_pte_mask);
	139
	140	return pte;
	141	}
	142
	143	static inline pteval_t pte_val_ma(pte_t pte)
	144	{
	145	return pte.pte;
	146	}
	147
	148	static inline pte_t __pte_ma(pteval_t x)
	149	{
	150	return (pte_t) { .pte = x };
	151	}
	152
20e71f2e IY	153	#define pmd_val_ma(v) ((v).pmd)
	154	#define pud_val_ma(v) ((v).pgd.pgd)
	155	#define __pmd_ma(x) ((pmd_t) { (x) } )
20e71f2e IY	156
	157	#define pgd_val_ma(x) ((x).pgd)
	158
	159
	160	xmaddr_t arbitrary_virt_to_machine(unsigned long address);
	161	void make_lowmem_page_readonly(void *vaddr);
	162	void make_lowmem_page_readwrite(void *vaddr);
	163
	164	#endif /* __XEN_PAGE_H */