/* Modify the p2m type of a range of gfns from ot to nt.
* Resets the access permissions. */
void p2m_change_type_range(struct domain *d,
unsigned long start, unsigned long end,
p2m_type_t ot, p2m_type_t nt)
{
p2m_access_t a;
p2m_type_t pt;
unsigned long gfn;
mfn_t mfn;
struct p2m_domain *p2m = p2m_get_hostp2m(d);
BUG_ON(p2m_is_grant(ot) || p2m_is_grant(nt));
p2m_lock(p2m);
p2m->defer_nested_flush = 1;
for ( gfn = start; gfn < end; gfn++ )
{
mfn = p2m->get_entry(p2m, gfn, &pt, &a, 0, NULL);
if ( pt == ot )
set_p2m_entry(p2m, gfn, mfn, PAGE_ORDER_4K, nt, p2m->default_access);
}
p2m->defer_nested_flush = 0;
if ( nestedhvm_enabled(d) )
p2m_flush_nestedp2m(d);
p2m_unlock(p2m);
}
int
set_mmio_p2m_entry(struct domain *d, unsigned long gfn, mfn_t mfn)
{
int rc = 0;
p2m_access_t a;
p2m_type_t ot;
mfn_t omfn;
struct p2m_domain *p2m = p2m_get_hostp2m(d);
if ( !paging_mode_translate(d) )
return 0;
gfn_lock(p2m, gfn, 0);
omfn = p2m->get_entry(p2m, gfn, &ot, &a, 0, NULL);
if ( p2m_is_grant(ot) )
{
p2m_unlock(p2m);
domain_crash(d);
return 0;
}
else if ( p2m_is_ram(ot) )
{
ASSERT(mfn_valid(omfn));
set_gpfn_from_mfn(mfn_x(omfn), INVALID_M2P_ENTRY);
}
P2M_DEBUG("set mmio %lx %lx\n", gfn, mfn_x(mfn));
rc = set_p2m_entry(p2m, gfn, mfn, PAGE_ORDER_4K, p2m_mmio_direct, p2m->default_access);
gfn_unlock(p2m, gfn, 0);
if ( 0 == rc )
gdprintk(XENLOG_ERR,
"set_mmio_p2m_entry: set_p2m_entry failed! mfn=%08lx\n",
mfn_x(get_gfn_query_unlocked(p2m->domain, gfn, &ot)));
return rc;
}
static void
p2m_remove_page(struct p2m_domain *p2m, unsigned long gfn, unsigned long mfn,
unsigned int page_order)
{
unsigned long i;
mfn_t mfn_return;
p2m_type_t t;
p2m_access_t a;
if ( !paging_mode_translate(p2m->domain) )
{
if ( need_iommu(p2m->domain) )
for ( i = 0; i < (1 << page_order); i++ )
iommu_unmap_page(p2m->domain, mfn + i);
return;
}
ASSERT(gfn_locked_by_me(p2m, gfn));
P2M_DEBUG("removing gfn=%#lx mfn=%#lx\n", gfn, mfn);
if ( mfn_valid(_mfn(mfn)) )
{
for ( i = 0; i < (1UL << page_order); i++ )
{
mfn_return = p2m->get_entry(p2m, gfn + i, &t, &a, 0, NULL);
if ( !p2m_is_grant(t) && !p2m_is_shared(t) )
set_gpfn_from_mfn(mfn+i, INVALID_M2P_ENTRY);
ASSERT( !p2m_is_valid(t) || mfn + i == mfn_x(mfn_return) );
}
}
set_p2m_entry(p2m, gfn, _mfn(INVALID_MFN), page_order, p2m_invalid, p2m->default_access);
}
/* Modify the p2m type of a single gfn from ot to nt, returning the
* entry's previous type. Resets the access permissions. */
p2m_type_t p2m_change_type(struct domain *d, unsigned long gfn,
p2m_type_t ot, p2m_type_t nt)
{
p2m_access_t a;
p2m_type_t pt;
mfn_t mfn;
struct p2m_domain *p2m = p2m_get_hostp2m(d);
BUG_ON(p2m_is_grant(ot) || p2m_is_grant(nt));
gfn_lock(p2m, gfn, 0);
mfn = p2m->get_entry(p2m, gfn, &pt, &a, 0, NULL);
if ( pt == ot )
set_p2m_entry(p2m, gfn, mfn, PAGE_ORDER_4K, nt, p2m->default_access);
gfn_unlock(p2m, gfn, 0);
return pt;
}
/* Atomically look up a GFN and take a reference count on the backing page. */
struct page_info *get_page_from_gfn_p2m(
struct domain *d, struct p2m_domain *p2m, unsigned long gfn,
p2m_type_t *t, p2m_access_t *a, p2m_query_t q)
{
struct page_info *page = NULL;
p2m_access_t _a;
p2m_type_t _t;
mfn_t mfn;
/* Allow t or a to be NULL */
t = t ?: &_t;
a = a ?: &_a;
if ( likely(!p2m_locked_by_me(p2m)) )
{
/* Fast path: look up and get out */
p2m_read_lock(p2m);
mfn = __get_gfn_type_access(p2m, gfn, t, a, 0, NULL, 0);
if ( (p2m_is_ram(*t) || p2m_is_grant(*t))
&& mfn_valid(mfn)
&& !((q & P2M_UNSHARE) && p2m_is_shared(*t)) )
{
page = mfn_to_page(mfn);
if ( !get_page(page, d)
/* Page could be shared */
&& !get_page(page, dom_cow) )
page = NULL;
}
p2m_read_unlock(p2m);
if ( page )
return page;
/* Error path: not a suitable GFN at all */
if ( !p2m_is_ram(*t) && !p2m_is_paging(*t) && !p2m_is_pod(*t) )
return NULL;
}
/* Slow path: take the write lock and do fixups */
mfn = get_gfn_type_access(p2m, gfn, t, a, q, NULL);
if ( p2m_is_ram(*t) && mfn_valid(mfn) )
{
page = mfn_to_page(mfn);
if ( !get_page(page, d) )
page = NULL;
}
put_gfn(d, gfn);
return page;
}
long p2m_pt_audit_p2m(struct p2m_domain *p2m)
{
unsigned long entry_count = 0, pmbad = 0;
unsigned long mfn, gfn, m2pfn;
int test_linear;
struct domain *d = p2m->domain;
ASSERT(p2m_locked_by_me(p2m));
ASSERT(pod_locked_by_me(p2m));
test_linear = ( (d == current->domain)
&& !pagetable_is_null(current->arch.monitor_table) );
if ( test_linear )
flush_tlb_local();
/* Audit part one: walk the domain's p2m table, checking the entries. */
if ( pagetable_get_pfn(p2m_get_pagetable(p2m)) != 0 )
{
l2_pgentry_t *l2e;
l1_pgentry_t *l1e;
int i1, i2;
#if CONFIG_PAGING_LEVELS == 4
l4_pgentry_t *l4e;
l3_pgentry_t *l3e;
int i4, i3;
l4e = map_domain_page(mfn_x(pagetable_get_mfn(p2m_get_pagetable(p2m))));
#else /* CONFIG_PAGING_LEVELS == 3 */
l3_pgentry_t *l3e;
int i3;
l3e = map_domain_page(mfn_x(pagetable_get_mfn(p2m_get_pagetable(p2m))));
#endif
gfn = 0;
#if CONFIG_PAGING_LEVELS >= 4
for ( i4 = 0; i4 < L4_PAGETABLE_ENTRIES; i4++ )
{
if ( !(l4e_get_flags(l4e[i4]) & _PAGE_PRESENT) )
{
gfn += 1 << (L4_PAGETABLE_SHIFT - PAGE_SHIFT);
continue;
}
l3e = map_domain_page(mfn_x(_mfn(l4e_get_pfn(l4e[i4]))));
#endif
for ( i3 = 0;
i3 < ((CONFIG_PAGING_LEVELS==4) ? L3_PAGETABLE_ENTRIES : 8);
i3++ )
{
if ( !(l3e_get_flags(l3e[i3]) & _PAGE_PRESENT) )
{
gfn += 1 << (L3_PAGETABLE_SHIFT - PAGE_SHIFT);
continue;
}
/* check for 1GB super page */
if ( l3e_get_flags(l3e[i3]) & _PAGE_PSE )
{
mfn = l3e_get_pfn(l3e[i3]);
ASSERT(mfn_valid(_mfn(mfn)));
/* we have to cover 512x512 4K pages */
for ( i2 = 0;
i2 < (L2_PAGETABLE_ENTRIES * L1_PAGETABLE_ENTRIES);
i2++)
{
m2pfn = get_gpfn_from_mfn(mfn+i2);
if ( m2pfn != (gfn + i2) )
{
pmbad++;
P2M_PRINTK("mismatch: gfn %#lx -> mfn %#lx"
" -> gfn %#lx\n", gfn+i2, mfn+i2,
m2pfn);
BUG();
}
gfn += 1 << (L3_PAGETABLE_SHIFT - PAGE_SHIFT);
continue;
}
}
l2e = map_domain_page(mfn_x(_mfn(l3e_get_pfn(l3e[i3]))));
for ( i2 = 0; i2 < L2_PAGETABLE_ENTRIES; i2++ )
{
if ( !(l2e_get_flags(l2e[i2]) & _PAGE_PRESENT) )
{
if ( (l2e_get_flags(l2e[i2]) & _PAGE_PSE)
&& ( p2m_flags_to_type(l2e_get_flags(l2e[i2]))
== p2m_populate_on_demand ) )
entry_count+=SUPERPAGE_PAGES;
gfn += 1 << (L2_PAGETABLE_SHIFT - PAGE_SHIFT);
continue;
}
/* check for super page */
if ( l2e_get_flags(l2e[i2]) & _PAGE_PSE )
{
mfn = l2e_get_pfn(l2e[i2]);
ASSERT(mfn_valid(_mfn(mfn)));
for ( i1 = 0; i1 < L1_PAGETABLE_ENTRIES; i1++)
{
m2pfn = get_gpfn_from_mfn(mfn+i1);
/* Allow shared M2Ps */
if ( (m2pfn != (gfn + i1)) &&
(m2pfn != SHARED_M2P_ENTRY) )
{
pmbad++;
P2M_PRINTK("mismatch: gfn %#lx -> mfn %#lx"
" -> gfn %#lx\n", gfn+i1, mfn+i1,
m2pfn);
BUG();
}
}
gfn += 1 << (L2_PAGETABLE_SHIFT - PAGE_SHIFT);
continue;
}
l1e = map_domain_page(mfn_x(_mfn(l2e_get_pfn(l2e[i2]))));
for ( i1 = 0; i1 < L1_PAGETABLE_ENTRIES; i1++, gfn++ )
{
p2m_type_t type;
type = p2m_flags_to_type(l1e_get_flags(l1e[i1]));
if ( !(l1e_get_flags(l1e[i1]) & _PAGE_PRESENT) )
{
if ( type == p2m_populate_on_demand )
entry_count++;
continue;
}
mfn = l1e_get_pfn(l1e[i1]);
ASSERT(mfn_valid(_mfn(mfn)));
m2pfn = get_gpfn_from_mfn(mfn);
if ( m2pfn != gfn &&
type != p2m_mmio_direct &&
!p2m_is_grant(type) &&
!p2m_is_shared(type) )
{
pmbad++;
printk("mismatch: gfn %#lx -> mfn %#lx"
" -> gfn %#lx\n", gfn, mfn, m2pfn);
P2M_PRINTK("mismatch: gfn %#lx -> mfn %#lx"
" -> gfn %#lx\n", gfn, mfn, m2pfn);
BUG();
}
}
unmap_domain_page(l1e);
}
unmap_domain_page(l2e);
}
#if CONFIG_PAGING_LEVELS >= 4
unmap_domain_page(l3e);
}
#endif
#if CONFIG_PAGING_LEVELS == 4
unmap_domain_page(l4e);
#else /* CONFIG_PAGING_LEVELS == 3 */
unmap_domain_page(l3e);
#endif
}
if ( entry_count != p2m->pod.entry_count )
{
printk("%s: refcounted entry count %ld, audit count %lu!\n",
__func__,
p2m->pod.entry_count,
entry_count);
BUG();
}
return pmbad;
}
/* Walk the whole p2m table, changing any entries of the old type
* to the new type. This is used in hardware-assisted paging to
* quickly enable or diable log-dirty tracking */
static void p2m_change_type_global(struct p2m_domain *p2m,
p2m_type_t ot, p2m_type_t nt)
{
unsigned long mfn, gfn, flags;
l1_pgentry_t l1e_content;
l1_pgentry_t *l1e;
l2_pgentry_t *l2e;
mfn_t l1mfn, l2mfn, l3mfn;
unsigned long i1, i2, i3;
l3_pgentry_t *l3e;
#if CONFIG_PAGING_LEVELS == 4
l4_pgentry_t *l4e;
unsigned long i4;
#endif /* CONFIG_PAGING_LEVELS == 4 */
BUG_ON(p2m_is_grant(ot) || p2m_is_grant(nt));
BUG_ON(ot != nt && (ot == p2m_mmio_direct || nt == p2m_mmio_direct));
if ( !paging_mode_translate(p2m->domain) )
return;
if ( pagetable_get_pfn(p2m_get_pagetable(p2m)) == 0 )
return;
ASSERT(p2m_locked_by_me(p2m));
#if CONFIG_PAGING_LEVELS == 4
l4e = map_domain_page(mfn_x(pagetable_get_mfn(p2m_get_pagetable(p2m))));
#else /* CONFIG_PAGING_LEVELS == 3 */
l3mfn = _mfn(mfn_x(pagetable_get_mfn(p2m_get_pagetable(p2m))));
l3e = map_domain_page(mfn_x(pagetable_get_mfn(p2m_get_pagetable(p2m))));
#endif
#if CONFIG_PAGING_LEVELS >= 4
for ( i4 = 0; i4 < L4_PAGETABLE_ENTRIES; i4++ )
{
if ( !(l4e_get_flags(l4e[i4]) & _PAGE_PRESENT) )
{
continue;
}
l3mfn = _mfn(l4e_get_pfn(l4e[i4]));
l3e = map_domain_page(l4e_get_pfn(l4e[i4]));
#endif
for ( i3 = 0;
i3 < ((CONFIG_PAGING_LEVELS==4) ? L3_PAGETABLE_ENTRIES : 8);
i3++ )
{
if ( !(l3e_get_flags(l3e[i3]) & _PAGE_PRESENT) )
{
continue;
}
if ( (l3e_get_flags(l3e[i3]) & _PAGE_PSE) )
{
flags = l3e_get_flags(l3e[i3]);
if ( p2m_flags_to_type(flags) != ot )
continue;
mfn = l3e_get_pfn(l3e[i3]);
gfn = get_gpfn_from_mfn(mfn);
flags = p2m_type_to_flags(nt, _mfn(mfn));
l1e_content = l1e_from_pfn(mfn, flags | _PAGE_PSE);
p2m->write_p2m_entry(p2m, gfn,
(l1_pgentry_t *)&l3e[i3],
l3mfn, l1e_content, 3);
continue;
}
l2mfn = _mfn(l3e_get_pfn(l3e[i3]));
l2e = map_domain_page(l3e_get_pfn(l3e[i3]));
for ( i2 = 0; i2 < L2_PAGETABLE_ENTRIES; i2++ )
{
if ( !(l2e_get_flags(l2e[i2]) & _PAGE_PRESENT) )
{
continue;
}
if ( (l2e_get_flags(l2e[i2]) & _PAGE_PSE) )
{
flags = l2e_get_flags(l2e[i2]);
if ( p2m_flags_to_type(flags) != ot )
continue;
mfn = l2e_get_pfn(l2e[i2]);
/* Do not use get_gpfn_from_mfn because it may return
SHARED_M2P_ENTRY */
gfn = (i2 + (i3
#if CONFIG_PAGING_LEVELS >= 4
+ (i4 * L3_PAGETABLE_ENTRIES)
#endif
)
* L2_PAGETABLE_ENTRIES) * L1_PAGETABLE_ENTRIES;
flags = p2m_type_to_flags(nt, _mfn(mfn));
l1e_content = l1e_from_pfn(mfn, flags | _PAGE_PSE);
p2m->write_p2m_entry(p2m, gfn,
(l1_pgentry_t *)&l2e[i2],
l2mfn, l1e_content, 2);
continue;
}
l1mfn = _mfn(l2e_get_pfn(l2e[i2]));
l1e = map_domain_page(mfn_x(l1mfn));
for ( i1 = 0; i1 < L1_PAGETABLE_ENTRIES; i1++, gfn++ )
{
flags = l1e_get_flags(l1e[i1]);
if ( p2m_flags_to_type(flags) != ot )
continue;
mfn = l1e_get_pfn(l1e[i1]);
gfn = i1 + (i2 + (i3
#if CONFIG_PAGING_LEVELS >= 4
+ (i4 * L3_PAGETABLE_ENTRIES)
#endif
)
* L2_PAGETABLE_ENTRIES) * L1_PAGETABLE_ENTRIES;
/* create a new 1le entry with the new type */
flags = p2m_type_to_flags(nt, _mfn(mfn));
l1e_content = p2m_l1e_from_pfn(mfn, flags);
p2m->write_p2m_entry(p2m, gfn, &l1e[i1],
l1mfn, l1e_content, 1);
}
unmap_domain_page(l1e);
}
unmap_domain_page(l2e);
}
#if CONFIG_PAGING_LEVELS >= 4
unmap_domain_page(l3e);
}
#endif
#if CONFIG_PAGING_LEVELS == 4
unmap_domain_page(l4e);
#else /* CONFIG_PAGING_LEVELS == 3 */
unmap_domain_page(l3e);
#endif
}
static mfn_t
p2m_gfn_to_mfn(struct p2m_domain *p2m, unsigned long gfn,
p2m_type_t *t, p2m_access_t *a, p2m_query_t q,
unsigned int *page_order)
{
mfn_t mfn;
paddr_t addr = ((paddr_t)gfn) << PAGE_SHIFT;
l2_pgentry_t *l2e;
l1_pgentry_t *l1e;
unsigned long l1e_flags;
p2m_type_t l1t;
ASSERT(paging_mode_translate(p2m->domain));
/* XXX This is for compatibility with the old model, where anything not
* XXX marked as RAM was considered to be emulated MMIO space.
* XXX Once we start explicitly registering MMIO regions in the p2m
* XXX we will return p2m_invalid for unmapped gfns */
*t = p2m_mmio_dm;
/* Not implemented except with EPT */
*a = p2m_access_rwx;
if ( gfn > p2m->max_mapped_pfn )
/* This pfn is higher than the highest the p2m map currently holds */
return _mfn(INVALID_MFN);
/* Use the fast path with the linear mapping if we can */
if ( p2m == p2m_get_hostp2m(current->domain) )
return p2m_gfn_to_mfn_current(p2m, gfn, t, a, q, page_order);
mfn = pagetable_get_mfn(p2m_get_pagetable(p2m));
#if CONFIG_PAGING_LEVELS >= 4
{
l4_pgentry_t *l4e = map_domain_page(mfn_x(mfn));
l4e += l4_table_offset(addr);
if ( (l4e_get_flags(*l4e) & _PAGE_PRESENT) == 0 )
{
unmap_domain_page(l4e);
return _mfn(INVALID_MFN);
}
mfn = _mfn(l4e_get_pfn(*l4e));
unmap_domain_page(l4e);
}
#endif
{
l3_pgentry_t *l3e = map_domain_page(mfn_x(mfn));
#if CONFIG_PAGING_LEVELS == 3
/* On PAE hosts the p2m has eight l3 entries, not four (see
* shadow_set_p2m_entry()) so we can't use l3_table_offset.
* Instead, just count the number of l3es from zero. It's safe
* to do this because we already checked that the gfn is within
* the bounds of the p2m. */
l3e += (addr >> L3_PAGETABLE_SHIFT);
#else
l3e += l3_table_offset(addr);
#endif
pod_retry_l3:
if ( (l3e_get_flags(*l3e) & _PAGE_PRESENT) == 0 )
{
if ( p2m_flags_to_type(l3e_get_flags(*l3e)) == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC )
{
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_1G, q) )
goto pod_retry_l3;
gdprintk(XENLOG_ERR, "%s: Allocate 1GB failed!\n", __func__);
}
else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l3e);
return _mfn(INVALID_MFN);
}
else if ( (l3e_get_flags(*l3e) & _PAGE_PSE) )
{
mfn = _mfn(l3e_get_pfn(*l3e) +
l2_table_offset(addr) * L1_PAGETABLE_ENTRIES +
l1_table_offset(addr));
*t = p2m_flags_to_type(l3e_get_flags(*l3e));
unmap_domain_page(l3e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t));
if ( page_order )
*page_order = PAGE_ORDER_1G;
return (p2m_is_valid(*t)) ? mfn : _mfn(INVALID_MFN);
}
mfn = _mfn(l3e_get_pfn(*l3e));
unmap_domain_page(l3e);
}
l2e = map_domain_page(mfn_x(mfn));
l2e += l2_table_offset(addr);
pod_retry_l2:
if ( (l2e_get_flags(*l2e) & _PAGE_PRESENT) == 0 )
{
/* PoD: Try to populate a 2-meg chunk */
if ( p2m_flags_to_type(l2e_get_flags(*l2e)) == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC ) {
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_2M, q) )
goto pod_retry_l2;
} else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l2e);
return _mfn(INVALID_MFN);
}
else if ( (l2e_get_flags(*l2e) & _PAGE_PSE) )
{
mfn = _mfn(l2e_get_pfn(*l2e) + l1_table_offset(addr));
*t = p2m_flags_to_type(l2e_get_flags(*l2e));
unmap_domain_page(l2e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t));
if ( page_order )
*page_order = PAGE_ORDER_2M;
return (p2m_is_valid(*t)) ? mfn : _mfn(INVALID_MFN);
}
mfn = _mfn(l2e_get_pfn(*l2e));
unmap_domain_page(l2e);
l1e = map_domain_page(mfn_x(mfn));
l1e += l1_table_offset(addr);
pod_retry_l1:
l1e_flags = l1e_get_flags(*l1e);
l1t = p2m_flags_to_type(l1e_flags);
if ( ((l1e_flags & _PAGE_PRESENT) == 0) && (!p2m_is_paging(l1t)) )
{
/* PoD: Try to populate */
if ( l1t == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC ) {
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_4K, q) )
goto pod_retry_l1;
} else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l1e);
return _mfn(INVALID_MFN);
}
mfn = _mfn(l1e_get_pfn(*l1e));
*t = l1t;
unmap_domain_page(l1e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t) || p2m_is_paging(*t));
if ( page_order )
*page_order = PAGE_ORDER_4K;
return (p2m_is_valid(*t) || p2m_is_grant(*t)) ? mfn : _mfn(INVALID_MFN);
}
/* Read the current domain's p2m table (through the linear mapping). */
static mfn_t p2m_gfn_to_mfn_current(struct p2m_domain *p2m,
unsigned long gfn, p2m_type_t *t,
p2m_access_t *a, p2m_query_t q,
unsigned int *page_order)
{
mfn_t mfn = _mfn(INVALID_MFN);
p2m_type_t p2mt = p2m_mmio_dm;
paddr_t addr = ((paddr_t)gfn) << PAGE_SHIFT;
/* XXX This is for compatibility with the old model, where anything not
* XXX marked as RAM was considered to be emulated MMIO space.
* XXX Once we start explicitly registering MMIO regions in the p2m
* XXX we will return p2m_invalid for unmapped gfns */
l1_pgentry_t l1e = l1e_empty(), *p2m_entry;
l2_pgentry_t l2e = l2e_empty();
int ret;
#if CONFIG_PAGING_LEVELS >= 4
l3_pgentry_t l3e = l3e_empty();
#endif
ASSERT(gfn < (RO_MPT_VIRT_END - RO_MPT_VIRT_START)
/ sizeof(l1_pgentry_t));
#if CONFIG_PAGING_LEVELS >= 4
/*
* Read & process L3
*/
p2m_entry = (l1_pgentry_t *)
&__linear_l2_table[l2_linear_offset(RO_MPT_VIRT_START)
+ l3_linear_offset(addr)];
pod_retry_l3:
ret = __copy_from_user(&l3e, p2m_entry, sizeof(l3e));
if ( ret != 0 || !(l3e_get_flags(l3e) & _PAGE_PRESENT) )
{
if ( (l3e_get_flags(l3e) & _PAGE_PSE) &&
(p2m_flags_to_type(l3e_get_flags(l3e)) == p2m_populate_on_demand) )
{
/* The read has succeeded, so we know that mapping exists */
if ( q & P2M_ALLOC )
{
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_1G, q) )
goto pod_retry_l3;
p2mt = p2m_invalid;
gdprintk(XENLOG_ERR, "%s: Allocate 1GB failed!\n", __func__);
goto out;
}
else
{
p2mt = p2m_populate_on_demand;
goto out;
}
}
goto pod_retry_l2;
}
if ( l3e_get_flags(l3e) & _PAGE_PSE )
{
p2mt = p2m_flags_to_type(l3e_get_flags(l3e));
ASSERT(l3e_get_pfn(l3e) != INVALID_MFN || !p2m_is_ram(p2mt));
if (p2m_is_valid(p2mt) )
mfn = _mfn(l3e_get_pfn(l3e) +
l2_table_offset(addr) * L1_PAGETABLE_ENTRIES +
l1_table_offset(addr));
else
p2mt = p2m_mmio_dm;
if ( page_order )
*page_order = PAGE_ORDER_1G;
goto out;
}
#endif
/*
* Read & process L2
*/
p2m_entry = &__linear_l1_table[l1_linear_offset(RO_MPT_VIRT_START)
+ l2_linear_offset(addr)];
pod_retry_l2:
ret = __copy_from_user(&l2e,
p2m_entry,
sizeof(l2e));
if ( ret != 0
|| !(l2e_get_flags(l2e) & _PAGE_PRESENT) )
{
if( (l2e_get_flags(l2e) & _PAGE_PSE)
&& ( p2m_flags_to_type(l2e_get_flags(l2e))
== p2m_populate_on_demand ) )
{
/* The read has succeeded, so we know that the mapping
* exits at this point. */
if ( q & P2M_ALLOC )
{
if ( !p2m_pod_demand_populate(p2m, gfn,
PAGE_ORDER_2M, q) )
goto pod_retry_l2;
/* Allocate failed. */
p2mt = p2m_invalid;
printk("%s: Allocate failed!\n", __func__);
goto out;
}
else
{
p2mt = p2m_populate_on_demand;
goto out;
}
}
goto pod_retry_l1;
}
if (l2e_get_flags(l2e) & _PAGE_PSE)
{
p2mt = p2m_flags_to_type(l2e_get_flags(l2e));
ASSERT(l2e_get_pfn(l2e) != INVALID_MFN || !p2m_is_ram(p2mt));
if ( p2m_is_valid(p2mt) )
mfn = _mfn(l2e_get_pfn(l2e) + l1_table_offset(addr));
else
p2mt = p2m_mmio_dm;
if ( page_order )
*page_order = PAGE_ORDER_2M;
goto out;
}
/*
* Read and process L1
*/
/* Need to __copy_from_user because the p2m is sparse and this
* part might not exist */
pod_retry_l1:
p2m_entry = &phys_to_machine_mapping[gfn];
ret = __copy_from_user(&l1e,
p2m_entry,
sizeof(l1e));
if ( ret == 0 ) {
unsigned long l1e_mfn = l1e_get_pfn(l1e);
p2mt = p2m_flags_to_type(l1e_get_flags(l1e));
ASSERT( mfn_valid(_mfn(l1e_mfn)) || !p2m_is_ram(p2mt) ||
p2m_is_paging(p2mt) );
if ( p2mt == p2m_populate_on_demand )
{
/* The read has succeeded, so we know that the mapping
* exits at this point. */
if ( q & P2M_ALLOC )
{
if ( !p2m_pod_demand_populate(p2m, gfn,
PAGE_ORDER_4K, q) )
goto pod_retry_l1;
/* Allocate failed. */
p2mt = p2m_invalid;
goto out;
}
else
{
p2mt = p2m_populate_on_demand;
goto out;
}
}
if ( p2m_is_valid(p2mt) || p2m_is_grant(p2mt) )
mfn = _mfn(l1e_mfn);
else
/* XXX see above */
p2mt = p2m_mmio_dm;
}
if ( page_order )
*page_order = PAGE_ORDER_4K;
out:
*t = p2mt;
return mfn;
}
static mfn_t
p2m_pt_get_entry(struct p2m_domain *p2m, unsigned long gfn,
p2m_type_t *t, p2m_access_t *a, p2m_query_t q,
unsigned int *page_order)
{
mfn_t mfn;
paddr_t addr = ((paddr_t)gfn) << PAGE_SHIFT;
l2_pgentry_t *l2e;
l1_pgentry_t *l1e;
unsigned long l1e_flags;
p2m_type_t l1t;
ASSERT(paging_mode_translate(p2m->domain));
/* XXX This is for compatibility with the old model, where anything not
* XXX marked as RAM was considered to be emulated MMIO space.
* XXX Once we start explicitly registering MMIO regions in the p2m
* XXX we will return p2m_invalid for unmapped gfns */
*t = p2m_mmio_dm;
/* Not implemented except with EPT */
*a = p2m_access_rwx;
if ( gfn > p2m->max_mapped_pfn )
/* This pfn is higher than the highest the p2m map currently holds */
return _mfn(INVALID_MFN);
mfn = pagetable_get_mfn(p2m_get_pagetable(p2m));
{
l4_pgentry_t *l4e = map_domain_page(mfn_x(mfn));
l4e += l4_table_offset(addr);
if ( (l4e_get_flags(*l4e) & _PAGE_PRESENT) == 0 )
{
unmap_domain_page(l4e);
return _mfn(INVALID_MFN);
}
mfn = _mfn(l4e_get_pfn(*l4e));
unmap_domain_page(l4e);
}
{
l3_pgentry_t *l3e = map_domain_page(mfn_x(mfn));
l3e += l3_table_offset(addr);
pod_retry_l3:
if ( (l3e_get_flags(*l3e) & _PAGE_PRESENT) == 0 )
{
if ( p2m_flags_to_type(l3e_get_flags(*l3e)) == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC )
{
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_1G, q) )
goto pod_retry_l3;
gdprintk(XENLOG_ERR, "%s: Allocate 1GB failed!\n", __func__);
}
else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l3e);
return _mfn(INVALID_MFN);
}
else if ( (l3e_get_flags(*l3e) & _PAGE_PSE) )
{
mfn = _mfn(l3e_get_pfn(*l3e) +
l2_table_offset(addr) * L1_PAGETABLE_ENTRIES +
l1_table_offset(addr));
*t = p2m_flags_to_type(l3e_get_flags(*l3e));
unmap_domain_page(l3e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t));
if ( page_order )
*page_order = PAGE_ORDER_1G;
return (p2m_is_valid(*t)) ? mfn : _mfn(INVALID_MFN);
}
mfn = _mfn(l3e_get_pfn(*l3e));
unmap_domain_page(l3e);
}
l2e = map_domain_page(mfn_x(mfn));
l2e += l2_table_offset(addr);
pod_retry_l2:
if ( (l2e_get_flags(*l2e) & _PAGE_PRESENT) == 0 )
{
/* PoD: Try to populate a 2-meg chunk */
if ( p2m_flags_to_type(l2e_get_flags(*l2e)) == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC ) {
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_2M, q) )
goto pod_retry_l2;
} else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l2e);
return _mfn(INVALID_MFN);
}
else if ( (l2e_get_flags(*l2e) & _PAGE_PSE) )
{
mfn = _mfn(l2e_get_pfn(*l2e) + l1_table_offset(addr));
*t = p2m_flags_to_type(l2e_get_flags(*l2e));
unmap_domain_page(l2e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t));
if ( page_order )
*page_order = PAGE_ORDER_2M;
return (p2m_is_valid(*t)) ? mfn : _mfn(INVALID_MFN);
}
mfn = _mfn(l2e_get_pfn(*l2e));
unmap_domain_page(l2e);
l1e = map_domain_page(mfn_x(mfn));
l1e += l1_table_offset(addr);
pod_retry_l1:
l1e_flags = l1e_get_flags(*l1e);
l1t = p2m_flags_to_type(l1e_flags);
if ( ((l1e_flags & _PAGE_PRESENT) == 0) && (!p2m_is_paging(l1t)) )
{
/* PoD: Try to populate */
if ( l1t == p2m_populate_on_demand )
{
if ( q & P2M_ALLOC ) {
if ( !p2m_pod_demand_populate(p2m, gfn, PAGE_ORDER_4K, q) )
goto pod_retry_l1;
} else
*t = p2m_populate_on_demand;
}
unmap_domain_page(l1e);
return _mfn(INVALID_MFN);
}
mfn = _mfn(l1e_get_pfn(*l1e));
*t = l1t;
unmap_domain_page(l1e);
ASSERT(mfn_valid(mfn) || !p2m_is_ram(*t) || p2m_is_paging(*t));
if ( page_order )
*page_order = PAGE_ORDER_4K;
return (p2m_is_valid(*t) || p2m_is_grant(*t)) ? mfn : _mfn(INVALID_MFN);
}
int
guest_physmap_add_entry(struct domain *d, unsigned long gfn,
unsigned long mfn, unsigned int page_order,
p2m_type_t t)
{
struct p2m_domain *p2m = p2m_get_hostp2m(d);
unsigned long i, ogfn;
p2m_type_t ot;
p2m_access_t a;
mfn_t omfn;
int pod_count = 0;
int rc = 0;
if ( !paging_mode_translate(d) )
{
if ( need_iommu(d) && t == p2m_ram_rw )
{
for ( i = 0; i < (1 << page_order); i++ )
{
rc = iommu_map_page(
d, mfn + i, mfn + i, IOMMUF_readable|IOMMUF_writable);
if ( rc != 0 )
{
while ( i-- > 0 )
iommu_unmap_page(d, mfn + i);
return rc;
}
}
}
return 0;
}
p2m_lock(p2m);
P2M_DEBUG("adding gfn=%#lx mfn=%#lx\n", gfn, mfn);
/* First, remove m->p mappings for existing p->m mappings */
for ( i = 0; i < (1UL << page_order); i++ )
{
omfn = p2m->get_entry(p2m, gfn + i, &ot, &a, 0, NULL);
if ( p2m_is_shared(ot) )
{
/* Do an unshare to cleanly take care of all corner
* cases. */
int rc;
rc = mem_sharing_unshare_page(p2m->domain, gfn + i, 0);
if ( rc )
{
p2m_unlock(p2m);
/* NOTE: Should a guest domain bring this upon itself,
* there is not a whole lot we can do. We are buried
* deep in locks from most code paths by now. So, fail
* the call and don't try to sleep on a wait queue
* while placing the mem event.
*
* However, all current (changeset 3432abcf9380) code
* paths avoid this unsavoury situation. For now.
*
* Foreign domains are okay to place an event as they
* won't go to sleep. */
(void)mem_sharing_notify_enomem(p2m->domain, gfn + i, 0);
return rc;
}
omfn = p2m->get_entry(p2m, gfn + i, &ot, &a, 0, NULL);
ASSERT(!p2m_is_shared(ot));
}
if ( p2m_is_grant(ot) )
{
/* Really shouldn't be unmapping grant maps this way */
domain_crash(d);
p2m_unlock(p2m);
return -EINVAL;
}
else if ( p2m_is_ram(ot) && !p2m_is_paged(ot) )
{
ASSERT(mfn_valid(omfn));
set_gpfn_from_mfn(mfn_x(omfn), INVALID_M2P_ENTRY);
}
else if ( ot == p2m_populate_on_demand )
{
/* Count how man PoD entries we'll be replacing if successful */
pod_count++;
}
else if ( p2m_is_paging(ot) && (ot != p2m_ram_paging_out) )
{
/* We're plugging a hole in the physmap where a paged out page was */
atomic_dec(&d->paged_pages);
}
}
/* Then, look for m->p mappings for this range and deal with them */
for ( i = 0; i < (1UL << page_order); i++ )
{
if ( page_get_owner(mfn_to_page(_mfn(mfn + i))) == dom_cow )
{
/* This is no way to add a shared page to your physmap! */
gdprintk(XENLOG_ERR, "Adding shared mfn %lx directly to dom %hu "
"physmap not allowed.\n", mfn+i, d->domain_id);
p2m_unlock(p2m);
return -EINVAL;
}
if ( page_get_owner(mfn_to_page(_mfn(mfn + i))) != d )
continue;
ogfn = mfn_to_gfn(d, _mfn(mfn+i));
if ( (ogfn != INVALID_M2P_ENTRY) && (ogfn != gfn + i) )
{
/* This machine frame is already mapped at another physical
* address */
P2M_DEBUG("aliased! mfn=%#lx, old gfn=%#lx, new gfn=%#lx\n",
mfn + i, ogfn, gfn + i);
omfn = p2m->get_entry(p2m, ogfn, &ot, &a, 0, NULL);
if ( p2m_is_ram(ot) && !p2m_is_paged(ot) )
{
ASSERT(mfn_valid(omfn));
P2M_DEBUG("old gfn=%#lx -> mfn %#lx\n",
ogfn , mfn_x(omfn));
if ( mfn_x(omfn) == (mfn + i) )
p2m_remove_page(p2m, ogfn, mfn + i, 0);
}
}
}
/* Now, actually do the two-way mapping */
if ( mfn_valid(_mfn(mfn)) )
{
if ( !set_p2m_entry(p2m, gfn, _mfn(mfn), page_order, t, p2m->default_access) )
{
rc = -EINVAL;
goto out; /* Failed to update p2m, bail without updating m2p. */
}
if ( !p2m_is_grant(t) )
{
for ( i = 0; i < (1UL << page_order); i++ )
set_gpfn_from_mfn(mfn+i, gfn+i);
}
}
else
{
gdprintk(XENLOG_WARNING, "Adding bad mfn to p2m map (%#lx -> %#lx)\n",
gfn, mfn);
if ( !set_p2m_entry(p2m, gfn, _mfn(INVALID_MFN), page_order,
p2m_invalid, p2m->default_access) )
rc = -EINVAL;
else
{
pod_lock(p2m);
p2m->pod.entry_count -= pod_count;
BUG_ON(p2m->pod.entry_count < 0);
pod_unlock(p2m);
}
}
out:
p2m_unlock(p2m);
return rc;
}
