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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_XEN_PAGE_H
#define _ASM_X86_XEN_PAGE_H
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/pfn.h>
#include <linux/mm.h>
#include <linux/device.h>
#include <asm/extable.h>
#include <asm/page.h>
#include <xen/interface/xen.h>
#include <xen/interface/grant_table.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;
#ifdef CONFIG_X86_64
#define XEN_PHYSICAL_MASK __sme_clr((1UL << 52) - 1)
#else
#define XEN_PHYSICAL_MASK __PHYSICAL_MASK
#endif
#define XEN_PTE_MFN_MASK ((pteval_t)(((signed long)PAGE_MASK) & \
XEN_PHYSICAL_MASK))
#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<<(BITS_PER_LONG-1))
#define IDENTITY_FRAME_BIT (1UL<<(BITS_PER_LONG-2))
#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT)
#define IDENTITY_FRAME(m) ((m) | IDENTITY_FRAME_BIT)
#define P2M_PER_PAGE (PAGE_SIZE / sizeof(unsigned long))
extern unsigned long *machine_to_phys_mapping;
extern unsigned long machine_to_phys_nr;
extern unsigned long *xen_p2m_addr;
extern unsigned long xen_p2m_size;
extern unsigned long xen_max_p2m_pfn;
extern int xen_alloc_p2m_entry(unsigned long pfn);
extern unsigned long get_phys_to_machine(unsigned long pfn);
extern bool set_phys_to_machine(unsigned long pfn, unsigned long mfn);
extern bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn);
extern unsigned long __init set_phys_range_identity(unsigned long pfn_s,
unsigned long pfn_e);
#ifdef CONFIG_XEN_PV
extern int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count);
extern int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_unmap_grant_ref *kunmap_ops,
struct page **pages, unsigned int count);
#else
static inline int
set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{
return 0;
}
static inline int
clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
struct gnttab_unmap_grant_ref *kunmap_ops,
struct page **pages, unsigned int count)
{
return 0;
}
#endif
/*
* Helper functions to write or read unsigned long values to/from
* memory, when the access may fault.
*/
static inline int xen_safe_write_ulong(unsigned long *addr, unsigned long val)
{
int ret = 0;
asm volatile("1: mov %[val], %[ptr]\n"
"2:\n"
".section .fixup, \"ax\"\n"
"3: sub $1, %[ret]\n"
" jmp 2b\n"
".previous\n"
_ASM_EXTABLE(1b, 3b)
: [ret] "+r" (ret), [ptr] "=m" (*addr)
: [val] "r" (val));
return ret;
}
static inline int xen_safe_read_ulong(const unsigned long *addr,
unsigned long *val)
{
int ret = 0;
unsigned long rval = ~0ul;
asm volatile("1: mov %[ptr], %[rval]\n"
"2:\n"
".section .fixup, \"ax\"\n"
"3: sub $1, %[ret]\n"
" jmp 2b\n"
".previous\n"
_ASM_EXTABLE(1b, 3b)
: [ret] "+r" (ret), [rval] "+r" (rval)
: [ptr] "m" (*addr));
*val = rval;
return ret;
}
#ifdef CONFIG_XEN_PV
/*
* When to use pfn_to_mfn(), __pfn_to_mfn() or get_phys_to_machine():
* - pfn_to_mfn() returns either INVALID_P2M_ENTRY or the mfn. No indicator
* bits (identity or foreign) are set.
* - __pfn_to_mfn() returns the found entry of the p2m table. A possibly set
* identity or foreign indicator will be still set. __pfn_to_mfn() is
* encapsulating get_phys_to_machine() which is called in special cases only.
* - get_phys_to_machine() is to be called by __pfn_to_mfn() only in special
* cases needing an extended handling.
*/
static inline unsigned long __pfn_to_mfn(unsigned long pfn)
{
unsigned long mfn;
if (pfn < xen_p2m_size)
mfn = xen_p2m_addr[pfn];
else if (unlikely(pfn < xen_max_p2m_pfn))
return get_phys_to_machine(pfn);
else
return IDENTITY_FRAME(pfn);
if (unlikely(mfn == INVALID_P2M_ENTRY))
return get_phys_to_machine(pfn);
return mfn;
}
#else
static inline unsigned long __pfn_to_mfn(unsigned long pfn)
{
return pfn;
}
#endif
static inline unsigned long pfn_to_mfn(unsigned long pfn)
{
unsigned long mfn;
/*
* Some x86 code are still using pfn_to_mfn instead of
* pfn_to_mfn. This will have to be removed when we figured
* out which call.
*/
if (xen_feature(XENFEAT_auto_translated_physmap))
return pfn;
mfn = __pfn_to_mfn(pfn);
if (mfn != INVALID_P2M_ENTRY)
mfn &= ~(FOREIGN_FRAME_BIT | IDENTITY_FRAME_BIT);
return mfn;
}
static inline int phys_to_machine_mapping_valid(unsigned long pfn)
{
if (xen_feature(XENFEAT_auto_translated_physmap))
return 1;
return __pfn_to_mfn(pfn) != INVALID_P2M_ENTRY;
}
static inline unsigned long mfn_to_pfn_no_overrides(unsigned long mfn)
{
unsigned long pfn;
int ret;
if (unlikely(mfn >= machine_to_phys_nr))
return ~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!
*/
ret = xen_safe_read_ulong(&machine_to_phys_mapping[mfn], &pfn);
if (ret < 0)
return ~0;
return pfn;
}
static inline unsigned long mfn_to_pfn(unsigned long mfn)
{
unsigned long pfn;
/*
* Some x86 code are still using mfn_to_pfn instead of
* gfn_to_pfn. This will have to be removed when we figure
* out which call.
*/
if (xen_feature(XENFEAT_auto_translated_physmap))
return mfn;
pfn = mfn_to_pfn_no_overrides(mfn);
if (__pfn_to_mfn(pfn) != mfn)
pfn = ~0;
/*
* pfn is ~0 if there are no entries in the m2p for mfn or the
* entry doesn't map back to the mfn.
*/
if (pfn == ~0 && __pfn_to_mfn(mfn) == IDENTITY_FRAME(mfn))
pfn = mfn;
return pfn;
}
static inline xmaddr_t phys_to_machine(xpaddr_t phys)
{
unsigned offset = phys.paddr & ~PAGE_MASK;
return XMADDR(PFN_PHYS(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(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
}
/* Pseudo-physical <-> Guest conversion */
static inline unsigned long pfn_to_gfn(unsigned long pfn)
{
if (xen_feature(XENFEAT_auto_translated_physmap))
return pfn;
else
return pfn_to_mfn(pfn);
}
static inline unsigned long gfn_to_pfn(unsigned long gfn)
{
if (xen_feature(XENFEAT_auto_translated_physmap))
return gfn;
else
return mfn_to_pfn(gfn);
}
/* Pseudo-physical <-> Bus conversion */
#define pfn_to_bfn(pfn) pfn_to_gfn(pfn)
#define bfn_to_pfn(bfn) gfn_to_pfn(bfn)
/*
* 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 bfn_to_local_pfn(unsigned long mfn)
{
unsigned long pfn;
if (xen_feature(XENFEAT_auto_translated_physmap))
return mfn;
pfn = mfn_to_pfn(mfn);
if (__pfn_to_mfn(pfn) != mfn)
return -1; /* force !pfn_valid() */
return pfn;
}
/* VIRT <-> MACHINE conversion */
#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v))))
#define virt_to_pfn(v) (PFN_DOWN(__pa(v)))
#define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v)))
#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT))
/* VIRT <-> GUEST conversion */
#define virt_to_gfn(v) (pfn_to_gfn(virt_to_pfn(v)))
#define gfn_to_virt(g) (__va(gfn_to_pfn(g) << PAGE_SHIFT))
static inline unsigned long pte_mfn(pte_t pte)
{
return (pte.pte & XEN_PTE_MFN_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) |
massage_pgprot(pgprot);
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)
#ifdef __PAGETABLE_PUD_FOLDED
#define pud_val_ma(v) ((v).p4d.pgd.pgd)
#else
#define pud_val_ma(v) ((v).pud)
#endif
#define __pmd_ma(x) ((pmd_t) { (x) } )
#ifdef __PAGETABLE_P4D_FOLDED
#define p4d_val_ma(x) ((x).pgd.pgd)
#else
#define p4d_val_ma(x) ((x).p4d)
#endif
xmaddr_t arbitrary_virt_to_machine(void *address);
unsigned long arbitrary_virt_to_mfn(void *vaddr);
void make_lowmem_page_readonly(void *vaddr);
void make_lowmem_page_readwrite(void *vaddr);
#define xen_remap(cookie, size) ioremap((cookie), (size))
#define xen_unmap(cookie) iounmap((cookie))
static inline bool xen_arch_need_swiotlb(struct device *dev,
phys_addr_t phys,
dma_addr_t dev_addr)
{
return false;
}
static inline unsigned long xen_get_swiotlb_free_pages(unsigned int order)
{
return __get_free_pages(__GFP_NOWARN, order);
}
#endif /* _ASM_X86_XEN_PAGE_H */
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