int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{
int i, ret;
pte_t *pte;
unsigned long mfn;
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
if (ret)
return ret;
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
for (i = 0; i < count; i++) {
/* Do not add to override if the map failed. */
if (map_ops[i].status)
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {
pte = (pte_t *) (mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
(map_ops[i].host_addr & ~PAGE_MASK));
mfn = pte_mfn(*pte);
} else {
mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
}
ret = m2p_add_override(mfn, pages[i], kmap_ops ?
&kmap_ops[i] : NULL);
if (ret)
return ret;
}
return ret;
}
/*
* Build the parallel p2m_top_mfn and p2m_mid_mfn structures
*
* This is called both at boot time, and after resuming from suspend:
* - At boot time we're called rather early, and must use alloc_bootmem*()
* to allocate memory.
*
* - After resume we're called from within stop_machine, but the mfn
* tree should already be completely allocated.
*/
void __ref xen_build_mfn_list_list(void)
{
unsigned long pfn, mfn;
pte_t *ptep;
unsigned int level, topidx, mididx;
unsigned long *mid_mfn_p;
if (xen_feature(XENFEAT_auto_translated_physmap))
return;
/* Pre-initialize p2m_top_mfn to be completely missing */
if (p2m_top_mfn == NULL) {
p2m_mid_missing_mfn = alloc_p2m_page();
p2m_mid_mfn_init(p2m_mid_missing_mfn, p2m_missing);
p2m_top_mfn_p = alloc_p2m_page();
p2m_top_mfn_p_init(p2m_top_mfn_p);
p2m_top_mfn = alloc_p2m_page();
p2m_top_mfn_init(p2m_top_mfn);
} else {
/* Reinitialise, mfn's all change after migration */
p2m_mid_mfn_init(p2m_mid_missing_mfn, p2m_missing);
}
for (pfn = 0; pfn < xen_max_p2m_pfn && pfn < MAX_P2M_PFN;
pfn += P2M_PER_PAGE) {
topidx = p2m_top_index(pfn);
mididx = p2m_mid_index(pfn);
mid_mfn_p = p2m_top_mfn_p[topidx];
ptep = lookup_address((unsigned long)(xen_p2m_addr + pfn),
&level);
BUG_ON(!ptep || level != PG_LEVEL_4K);
mfn = pte_mfn(*ptep);
ptep = (pte_t *)((unsigned long)ptep & ~(PAGE_SIZE - 1));
/* Don't bother allocating any mfn mid levels if
* they're just missing, just update the stored mfn,
* since all could have changed over a migrate.
*/
if (ptep == p2m_missing_pte || ptep == p2m_identity_pte) {
BUG_ON(mididx);
BUG_ON(mid_mfn_p != p2m_mid_missing_mfn);
p2m_top_mfn[topidx] = virt_to_mfn(p2m_mid_missing_mfn);
pfn += (P2M_MID_PER_PAGE - 1) * P2M_PER_PAGE;
continue;
}
if (mid_mfn_p == p2m_mid_missing_mfn) {
mid_mfn_p = alloc_p2m_page();
p2m_mid_mfn_init(mid_mfn_p, p2m_missing);
p2m_top_mfn_p[topidx] = mid_mfn_p;
}
p2m_top_mfn[topidx] = virt_to_mfn(mid_mfn_p);
mid_mfn_p[mididx] = mfn;
}
}
xmaddr_t arbitrary_virt_to_machine(unsigned long address)
{
pte_t *pte = lookup_address(address);
unsigned offset = address & PAGE_MASK;
BUG_ON(pte == NULL);
return XMADDR((pte_mfn(*pte) << PAGE_SHIFT) + offset);
}
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)
{
int i, ret = 0;
bool lazy = false;
pte_t *pte;
if (xen_feature(XENFEAT_auto_translated_physmap))
return 0;
if (kmap_ops &&
!in_interrupt() &&
paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
arch_enter_lazy_mmu_mode();
lazy = true;
}
for (i = 0; i < count; i++) {
unsigned long mfn, pfn;
/* Do not add to override if the map failed. */
if (map_ops[i].status)
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {
pte = (pte_t *)(mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
(map_ops[i].host_addr & ~PAGE_MASK));
mfn = pte_mfn(*pte);
} else {
mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
}
pfn = page_to_pfn(pages[i]);
WARN_ON(PagePrivate(pages[i]));
SetPagePrivate(pages[i]);
set_page_private(pages[i], mfn);
pages[i]->index = pfn_to_mfn(pfn);
if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn)))) {
ret = -ENOMEM;
goto out;
}
if (kmap_ops) {
ret = m2p_add_override(mfn, pages[i], &kmap_ops[i]);
if (ret)
goto out;
}
}
out:
if (lazy)
arch_leave_lazy_mmu_mode();
return ret;
}
static xen_pfn_t pvh_get_grant_pfn(int grant_idx)
{
unsigned long vaddr;
unsigned int level;
pte_t *pte;
vaddr = (unsigned long)(gnttab_shared.addr) + grant_idx * PAGE_SIZE;
pte = lookup_address(vaddr, &level);
BUG_ON(pte == NULL);
return pte_mfn(*pte);
}
int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count)
{
int i, ret;
bool lazy = false;
pte_t *pte;
unsigned long mfn;
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
if (ret)
return ret;
/* Retry eagain maps */
for (i = 0; i < count; i++)
if (map_ops[i].status == GNTST_eagain)
gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, map_ops + i,
&map_ops[i].status, __func__);
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
if (!in_interrupt() && paravirt_get_lazy_mode() == PARAVIRT_LAZY_NONE) {
arch_enter_lazy_mmu_mode();
lazy = true;
}
for (i = 0; i < count; i++) {
/* Do not add to override if the map failed. */
if (map_ops[i].status)
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {
pte = (pte_t *) (mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
(map_ops[i].host_addr & ~PAGE_MASK));
mfn = pte_mfn(*pte);
} else {
mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
}
ret = m2p_add_override(mfn, pages[i], kmap_ops ?
&kmap_ops[i] : NULL);
if (ret)
goto out;
}
out:
if (lazy)
arch_leave_lazy_mmu_mode();
return ret;
}
int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct page **pages, unsigned int count)
{
int i, ret;
pte_t *pte;
unsigned long mfn;
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
if (ret)
return ret;
if (xen_feature(XENFEAT_auto_translated_physmap))
return ret;
for (i = 0; i < count; i++) {
/* Do not add to override if the map failed. */
if (map_ops[i].status)
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {
pte = (pte_t *) (mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
(map_ops[i].host_addr & ~PAGE_MASK));
mfn = pte_mfn(*pte);
} else {
/* If you really wanted to do this:
* mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
*
* The reason we do not implement it is b/c on the
* unmap path (gnttab_unmap_refs) we have no means of
* checking whether the page is !GNTMAP_contains_pte.
*
* That is without some extra data-structure to carry
* the struct page, bool clear_pte, and list_head next
* tuples and deal with allocation/delallocation, etc.
*
* The users of this API set the GNTMAP_contains_pte
* flag so lets just return not supported until it
* becomes neccessary to implement.
*/
return -EOPNOTSUPP;
}
ret = m2p_add_override(mfn, pages[i],
map_ops[i].flags & GNTMAP_contains_pte);
if (ret)
return ret;
}
return ret;
}
xmaddr_t arbitrary_virt_to_machine(void *vaddr)
{
unsigned long address = (unsigned long)vaddr;
unsigned int level;
pte_t *pte;
unsigned offset;
if (virt_addr_valid(vaddr))
return virt_to_machine(vaddr);
pte = lookup_address(address, &level);
BUG_ON(pte == NULL);
offset = address & ~PAGE_MASK;
return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
}
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)
{
int i, ret = 0;
pte_t *pte;
if (xen_feature(XENFEAT_auto_translated_physmap))
return 0;
if (kmap_ops) {
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref,
kmap_ops, count);
if (ret)
goto out;
}
for (i = 0; i < count; i++) {
unsigned long mfn, pfn;
/* Do not add to override if the map failed. */
if (map_ops[i].status)
continue;
if (map_ops[i].flags & GNTMAP_contains_pte) {
pte = (pte_t *)(mfn_to_virt(PFN_DOWN(map_ops[i].host_addr)) +
(map_ops[i].host_addr & ~PAGE_MASK));
mfn = pte_mfn(*pte);
} else {
mfn = PFN_DOWN(map_ops[i].dev_bus_addr);
}
pfn = page_to_pfn(pages[i]);
WARN(pfn_to_mfn(pfn) != INVALID_P2M_ENTRY, "page must be ballooned");
if (unlikely(!set_phys_to_machine(pfn, FOREIGN_FRAME(mfn)))) {
ret = -ENOMEM;
goto out;
}
}
out:
return ret;
}
xmaddr_t arbitrary_virt_to_machine(void *vaddr)
{
unsigned long address = (unsigned long)vaddr;
unsigned int level;
pte_t *pte;
unsigned offset;
/*
* if the PFN is in the linear mapped vaddr range, we can just use
* the (quick) virt_to_machine() p2m lookup
*/
if (virt_addr_valid(vaddr))
return virt_to_machine(vaddr);
/* otherwise we have to do a (slower) full page-table walk */
pte = lookup_address(address, &level);
BUG_ON(pte == NULL);
offset = address & ~PAGE_MASK;
return XMADDR(((phys_addr_t)pte_mfn(*pte) << PAGE_SHIFT) + offset);
}
static int dealloc_pte_fn(
pte_t *pte, struct page *pmd_page, unsigned long addr, void *data)
{
unsigned long mfn = pte_mfn(*pte);
int ret;
struct xen_memory_reservation reservation = {
.nr_extents = 1,
.extent_order = 0,
.domid = DOMID_SELF
};
set_xen_guest_handle(reservation.extent_start, &mfn);
set_pte_at(&init_mm, addr, pte, __pte_ma(0));
set_phys_to_machine(__pa(addr) >> PAGE_SHIFT, INVALID_P2M_ENTRY);
ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
BUG_ON(ret != 1);
return 0;
}
#endif
struct page **alloc_empty_pages_and_pagevec(int nr_pages)
{
unsigned long vaddr, flags;
struct page *page, **pagevec;
int i, ret;
pagevec = kmalloc(sizeof(page) * nr_pages, GFP_KERNEL);
if (pagevec == NULL)
return NULL;
for (i = 0; i < nr_pages; i++) {
page = pagevec[i] = alloc_page(GFP_KERNEL);
if (page == NULL)
goto err;
vaddr = (unsigned long)page_address(page);
scrub_pages(vaddr, 1);
balloon_lock(flags);
if (xen_feature(XENFEAT_auto_translated_physmap)) {
unsigned long gmfn = page_to_pfn(page);
struct xen_memory_reservation reservation = {
.nr_extents = 1,
.extent_order = 0,
.domid = DOMID_SELF
};
set_xen_guest_handle(reservation.extent_start, &gmfn);
ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
&reservation);
if (ret == 1)
ret = 0; /* success */
} else {
#ifdef CONFIG_XEN
ret = apply_to_page_range(&init_mm, vaddr, PAGE_SIZE,
dealloc_pte_fn, NULL);
#else
/* Cannot handle non-auto translate mode. */
ret = 1;
#endif
}
if (ret != 0) {
balloon_unlock(flags);
__free_page(page);
goto err;
}
totalram_pages = --current_pages;
balloon_unlock(flags);
}
out:
schedule_work(&balloon_worker);
#ifdef CONFIG_XEN
flush_tlb_all();
#endif
return pagevec;
err:
balloon_lock(flags);
while (--i >= 0)
balloon_append(pagevec[i]);
balloon_unlock(flags);
kfree(pagevec);
pagevec = NULL;
goto out;
}
