void share_xen_page_with_guest(
struct page_info *page, struct domain *d, int readonly)
{
if ( page_get_owner(page) == d )
return;
/* this causes us to leak pages in the Domain and reuslts in
* Zombie domains, I think we are missing a piece, until we find
* it we disable the following code */
set_gpfn_from_mfn(page_to_mfn(page), INVALID_M2P_ENTRY);
spin_lock(&d->page_alloc_lock);
/* The incremented type count pins as writable or read-only. */
page->u.inuse.type_info = (readonly ? PGT_none : PGT_writable_page);
page->u.inuse.type_info |= PGT_validated | 1;
page_set_owner(page, d);
wmb(); /* install valid domain ptr before updating refcnt. */
ASSERT(page->count_info == 0);
/* Only add to the allocation list if the domain isn't dying. */
if ( !d->is_dying )
{
page->count_info |= PGC_allocated | 1;
if ( unlikely(d->xenheap_pages++ == 0) )
get_knownalive_domain(d);
list_add_tail(&page->list, &d->xenpage_list);
}
spin_unlock(&d->page_alloc_lock);
}
void share_xen_page_with_guest(struct page_info *page,
struct domain *d, int readonly)
{
if ( page_get_owner(page) == d )
return;
spin_lock(&d->page_alloc_lock);
/* The incremented type count pins as writable or read-only. */
page->u.inuse.type_info = (readonly ? PGT_none : PGT_writable_page);
page->u.inuse.type_info |= PGT_validated | 1;
page_set_owner(page, d);
wmb(); /* install valid domain ptr before updating refcnt. */
ASSERT((page->count_info & ~PGC_xen_heap) == 0);
/* Only add to the allocation list if the domain isn't dying. */
if ( !d->is_dying )
{
page->count_info |= PGC_allocated | 1;
if ( unlikely(d->xenheap_pages++ == 0) )
get_knownalive_domain(d);
page_list_add_tail(page, &d->xenpage_list);
}
spin_unlock(&d->page_alloc_lock);
}
void hap_free_p2m_page(struct domain *d, struct page_info *pg)
{
hap_lock(d);
ASSERT(page_get_owner(pg) == d);
/* Should have just the one ref we gave it in alloc_p2m_page() */
if ( (pg->count_info & PGC_count_mask) != 1 )
HAP_ERROR("Odd p2m page count c=%#x t=%"PRtype_info"\n",
pg->count_info, pg->u.inuse.type_info);
pg->count_info = 0;
/* Free should not decrement domain's total allocation, since
* these pages were allocated without an owner. */
page_set_owner(pg, NULL);
free_domheap_page(pg);
d->arch.paging.hap.p2m_pages--;
ASSERT(d->arch.paging.hap.p2m_pages >= 0);
hap_unlock(d);
}
static int
share_xenoprof_page_with_guest(struct domain *d, unsigned long mfn, int npages)
{
int i;
/* Check if previous page owner has released the page. */
for ( i = 0; i < npages; i++ )
{
struct page_info *page = mfn_to_page(mfn + i);
if ( (page->count_info & (PGC_allocated|PGC_count_mask)) != 0 )
{
gdprintk(XENLOG_INFO, "mfn 0x%lx page->count_info 0x%lx\n",
mfn + i, (unsigned long)page->count_info);
return -EBUSY;
}
page_set_owner(page, NULL);
}
for ( i = 0; i < npages; i++ )
share_xen_page_with_guest(mfn_to_page(mfn + i), d, XENSHARE_writable);
return 0;
}
static struct page_info *hap_alloc_p2m_page(struct domain *d)
{
struct page_info *pg;
hap_lock(d);
pg = hap_alloc(d);
#if CONFIG_PAGING_LEVELS == 3
/* Under PAE mode, top-level P2M table should be allocated below 4GB space
* because the size of h_cr3 is only 32-bit. We use alloc_domheap_pages to
* force this requirement, and exchange the guaranteed 32-bit-clean
* page for the one we just hap_alloc()ed. */
if ( d->arch.paging.hap.p2m_pages == 0
&& mfn_x(page_to_mfn(pg)) >= (1UL << (32 - PAGE_SHIFT)) )
{
free_domheap_page(pg);
pg = alloc_domheap_pages(NULL, 0, MEMF_bits(32));
if ( likely(pg != NULL) )
{
void *p = hap_map_domain_page(page_to_mfn(pg));
clear_page(p);
hap_unmap_domain_page(p);
}
}
#endif
if ( likely(pg != NULL) )
{
d->arch.paging.hap.total_pages--;
d->arch.paging.hap.p2m_pages++;
page_set_owner(pg, d);
pg->count_info = 1;
}
hap_unlock(d);
return pg;
}
