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#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 & ~_PAGE_NX) >> 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 };
}
#ifdef CONFIG_X86_PAE
#define pmd_val_ma(v) ((v).pmd)
#define pud_val_ma(v) ((v).pgd.pgd)
#define __pmd_ma(x) ((pmd_t) { (x) } )
#else /* !X86_PAE */
#define pmd_val_ma(v) ((v).pud.pgd.pgd)
#endif /* CONFIG_X86_PAE */
#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 */
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