static int p2m_shatter_page(struct domain *d,
lpae_t *entry,
unsigned int level,
bool_t flush_cache)
{
const paddr_t level_shift = level_shifts[level];
int rc = p2m_create_table(d, entry,
level_shift - PAGE_SHIFT, flush_cache);
if ( !rc )
{
struct p2m_domain *p2m = &d->arch.p2m;
p2m->stats.shattered[level]++;
p2m->stats.mappings[level]--;
p2m->stats.mappings[level+1] += LPAE_ENTRIES;
}
return rc;
}
static lpae_t mfn_to_p2m_entry(unsigned long mfn, unsigned int mattr,
p2m_type_t t)
{
paddr_t pa = ((paddr_t) mfn) << PAGE_SHIFT;
/* xn and write bit will be defined in the switch */
lpae_t e = (lpae_t) {
.p2m.af = 1,
.p2m.sh = LPAE_SH_OUTER,
.p2m.read = 1,
.p2m.mattr = mattr,
.p2m.table = 1,
.p2m.valid = 1,
.p2m.type = t,
};
BUILD_BUG_ON(p2m_max_real_type > (1 << 4));
switch (t)
{
case p2m_ram_rw:
e.p2m.xn = 0;
e.p2m.write = 1;
break;
case p2m_ram_ro:
e.p2m.xn = 0;
e.p2m.write = 0;
break;
case p2m_map_foreign:
case p2m_grant_map_rw:
case p2m_mmio_direct:
e.p2m.xn = 1;
e.p2m.write = 1;
break;
case p2m_grant_map_ro:
case p2m_invalid:
e.p2m.xn = 1;
e.p2m.write = 0;
break;
case p2m_max_real_type:
BUG();
break;
}
ASSERT(!(pa & ~PAGE_MASK));
ASSERT(!(pa & ~PADDR_MASK));
e.bits |= pa;
return e;
}
/* Allocate a new page table page and hook it in via the given entry */
static int p2m_create_table(struct domain *d,
lpae_t *entry)
{
struct p2m_domain *p2m = &d->arch.p2m;
struct page_info *page;
void *p;
lpae_t pte;
BUG_ON(entry->p2m.valid);
page = alloc_domheap_page(NULL, 0);
if ( page == NULL )
return -ENOMEM;
page_list_add(page, &p2m->pages);
p = __map_domain_page(page);
clear_page(p);
unmap_domain_page(p);
pte = mfn_to_p2m_entry(page_to_mfn(page), MATTR_MEM, p2m_invalid);
write_pte(entry, pte);
return 0;
}
enum p2m_operation {
INSERT,
ALLOCATE,
REMOVE,
RELINQUISH,
CACHEFLUSH,
};
static int apply_p2m_changes(struct domain *d,
enum p2m_operation op,
paddr_t start_gpaddr,
paddr_t end_gpaddr,
paddr_t maddr,
int mattr,
p2m_type_t t)
{
int rc;
struct p2m_domain *p2m = &d->arch.p2m;
lpae_t *first = NULL, *second = NULL, *third = NULL;
paddr_t addr;
unsigned long cur_first_page = ~0,
cur_first_offset = ~0,
cur_second_offset = ~0;
unsigned long count = 0;
unsigned int flush = 0;
bool_t populate = (op == INSERT || op == ALLOCATE);
lpae_t pte;
spin_lock(&p2m->lock);
if ( d != current->domain )
p2m_load_VTTBR(d);
addr = start_gpaddr;
while ( addr < end_gpaddr )
{
if ( cur_first_page != p2m_first_level_index(addr) )
{
if ( first ) unmap_domain_page(first);
first = p2m_map_first(p2m, addr);
if ( !first )
{
rc = -EINVAL;
goto out;
}
cur_first_page = p2m_first_level_index(addr);
}
if ( !first[first_table_offset(addr)].p2m.valid )
{
if ( !populate )
{
addr = (addr + FIRST_SIZE) & FIRST_MASK;
continue;
}
rc = p2m_create_table(d, &first[first_table_offset(addr)]);
if ( rc < 0 )
{
printk("p2m_populate_ram: L1 failed\n");
goto out;
}
}
BUG_ON(!first[first_table_offset(addr)].p2m.valid);
if ( cur_first_offset != first_table_offset(addr) )
{
if (second) unmap_domain_page(second);
second = map_domain_page(first[first_table_offset(addr)].p2m.base);
cur_first_offset = first_table_offset(addr);
}
/* else: second already valid */
if ( !second[second_table_offset(addr)].p2m.valid )
{
if ( !populate )
{
addr = (addr + SECOND_SIZE) & SECOND_MASK;
continue;
}
rc = p2m_create_table(d, &second[second_table_offset(addr)]);
if ( rc < 0 ) {
printk("p2m_populate_ram: L2 failed\n");
goto out;
}
}
BUG_ON(!second[second_table_offset(addr)].p2m.valid);
if ( cur_second_offset != second_table_offset(addr) )
{
/* map third level */
if (third) unmap_domain_page(third);
third = map_domain_page(second[second_table_offset(addr)].p2m.base);
cur_second_offset = second_table_offset(addr);
}
pte = third[third_table_offset(addr)];
flush |= pte.p2m.valid;
/* TODO: Handle other p2m type
*
* It's safe to do the put_page here because page_alloc will
* flush the TLBs if the page is reallocated before the end of
* this loop.
*/
if ( pte.p2m.valid && p2m_is_foreign(pte.p2m.type) )
{
unsigned long mfn = pte.p2m.base;
ASSERT(mfn_valid(mfn));
put_page(mfn_to_page(mfn));
}
/* Allocate a new RAM page and attach */
switch (op) {
case ALLOCATE:
{
struct page_info *page;
ASSERT(!pte.p2m.valid);
rc = -ENOMEM;
page = alloc_domheap_page(d, 0);
if ( page == NULL ) {
printk("p2m_populate_ram: failed to allocate page\n");
goto out;
}
pte = mfn_to_p2m_entry(page_to_mfn(page), mattr, t);
write_pte(&third[third_table_offset(addr)], pte);
}
break;
case INSERT:
{
pte = mfn_to_p2m_entry(maddr >> PAGE_SHIFT, mattr, t);
write_pte(&third[third_table_offset(addr)], pte);
maddr += PAGE_SIZE;
}
break;
case RELINQUISH:
case REMOVE:
{
if ( !pte.p2m.valid )
{
count++;
break;
}
count += 0x10;
memset(&pte, 0x00, sizeof(pte));
write_pte(&third[third_table_offset(addr)], pte);
count++;
}
break;
case CACHEFLUSH:
{
if ( !pte.p2m.valid || !p2m_is_ram(pte.p2m.type) )
break;
flush_page_to_ram(pte.p2m.base);
}
break;
}
/* Preempt every 2MiB (mapped) or 32 MiB (unmapped) - arbitrary */
if ( op == RELINQUISH && count >= 0x2000 )
{
if ( hypercall_preempt_check() )
{
p2m->lowest_mapped_gfn = addr >> PAGE_SHIFT;
rc = -EAGAIN;
goto out;
}
count = 0;
}
/* Got the next page */
addr += PAGE_SIZE;
}
if ( flush )
{
/* At the beginning of the function, Xen is updating VTTBR
* with the domain where the mappings are created. In this
* case it's only necessary to flush TLBs on every CPUs with
* the current VMID (our domain).
*/
flush_tlb();
}
if ( op == ALLOCATE || op == INSERT )
{
unsigned long sgfn = paddr_to_pfn(start_gpaddr);
unsigned long egfn = paddr_to_pfn(end_gpaddr);
p2m->max_mapped_gfn = MAX(p2m->max_mapped_gfn, egfn);
p2m->lowest_mapped_gfn = MIN(p2m->lowest_mapped_gfn, sgfn);
}
rc = 0;
out:
if (third) unmap_domain_page(third);
if (second) unmap_domain_page(second);
if (first) unmap_domain_page(first);
if ( d != current->domain )
p2m_load_VTTBR(current->domain);
spin_unlock(&p2m->lock);
return rc;
}
static int create_p2m_entries(struct domain *d,
enum p2m_operation op,
paddr_t start_gpaddr,
paddr_t end_gpaddr,
paddr_t maddr,
int mattr)
{
int rc, flush;
struct p2m_domain *p2m = &d->arch.p2m;
lpae_t *first = NULL, *second = NULL, *third = NULL;
paddr_t addr;
unsigned long cur_first_offset = ~0, cur_second_offset = ~0;
spin_lock(&p2m->lock);
/* XXX Don't actually handle 40 bit guest physical addresses */
BUG_ON(start_gpaddr & 0x8000000000ULL);
BUG_ON(end_gpaddr & 0x8000000000ULL);
first = __map_domain_page(p2m->first_level);
for(addr = start_gpaddr; addr < end_gpaddr; addr += PAGE_SIZE)
{
if ( !first[first_table_offset(addr)].p2m.valid )
{
rc = p2m_create_table(d, &first[first_table_offset(addr)]);
if ( rc < 0 ) {
printk("p2m_populate_ram: L1 failed\n");
goto out;
}
}
BUG_ON(!first[first_table_offset(addr)].p2m.valid);
if ( cur_first_offset != first_table_offset(addr) )
{
if (second) unmap_domain_page(second);
second = map_domain_page(first[first_table_offset(addr)].p2m.base);
cur_first_offset = first_table_offset(addr);
}
/* else: second already valid */
if ( !second[second_table_offset(addr)].p2m.valid )
{
rc = p2m_create_table(d, &second[second_table_offset(addr)]);
if ( rc < 0 ) {
printk("p2m_populate_ram: L2 failed\n");
goto out;
}
}
BUG_ON(!second[second_table_offset(addr)].p2m.valid);
if ( cur_second_offset != second_table_offset(addr) )
{
/* map third level */
if (third) unmap_domain_page(third);
third = map_domain_page(second[second_table_offset(addr)].p2m.base);
cur_second_offset = second_table_offset(addr);
}
flush = third[third_table_offset(addr)].p2m.valid;
/* Allocate a new RAM page and attach */
switch (op) {
case ALLOCATE:
{
struct page_info *page;
lpae_t pte;
rc = -ENOMEM;
page = alloc_domheap_page(d, 0);
if ( page == NULL ) {
printk("p2m_populate_ram: failed to allocate page\n");
goto out;
}
pte = mfn_to_p2m_entry(page_to_mfn(page), mattr);
write_pte(&third[third_table_offset(addr)], pte);
}
break;
case INSERT:
{
lpae_t pte = mfn_to_p2m_entry(maddr >> PAGE_SHIFT, mattr);
write_pte(&third[third_table_offset(addr)], pte);
maddr += PAGE_SIZE;
}
break;
case REMOVE:
{
lpae_t pte;
memset(&pte, 0x00, sizeof(pte));
write_pte(&third[third_table_offset(addr)], pte);
maddr += PAGE_SIZE;
}
break;
}
if ( flush )
flush_tlb_all_local();
}
rc = 0;
out:
if (third) unmap_domain_page(third);
if (second) unmap_domain_page(second);
if (first) unmap_domain_page(first);
spin_unlock(&p2m->lock);
return rc;
}
/*
* 0 == (P2M_ONE_DESCEND) continue to descend the tree
* +ve == (P2M_ONE_PROGRESS_*) handled at this level, continue, flush,
* entry, addr and maddr updated. Return value is an
* indication of the amount of work done (for preemption).
* -ve == (-Exxx) error.
*/
static int apply_one_level(struct domain *d,
lpae_t *entry,
unsigned int level,
bool_t flush_cache,
enum p2m_operation op,
paddr_t start_gpaddr,
paddr_t end_gpaddr,
paddr_t *addr,
paddr_t *maddr,
bool_t *flush,
int mattr,
p2m_type_t t,
p2m_access_t a)
{
const paddr_t level_size = level_sizes[level];
const paddr_t level_mask = level_masks[level];
const paddr_t level_shift = level_shifts[level];
struct p2m_domain *p2m = &d->arch.p2m;
lpae_t pte;
const lpae_t orig_pte = *entry;
int rc;
BUG_ON(level > 3);
switch ( op )
{
case ALLOCATE:
ASSERT(level < 3 || !p2m_valid(orig_pte));
ASSERT(*maddr == 0);
if ( p2m_valid(orig_pte) )
return P2M_ONE_DESCEND;
if ( is_mapping_aligned(*addr, end_gpaddr, 0, level_size) &&
/* We only create superpages when mem_access is not in use. */
(level == 3 || (level < 3 && !p2m->mem_access_enabled)) )
{
struct page_info *page;
page = alloc_domheap_pages(d, level_shift - PAGE_SHIFT, 0);
if ( page )
{
rc = p2m_mem_access_radix_set(p2m, paddr_to_pfn(*addr), a);
if ( rc < 0 )
{
free_domheap_page(page);
return rc;
}
pte = mfn_to_p2m_entry(page_to_mfn(page), mattr, t, a);
if ( level < 3 )
pte.p2m.table = 0;
p2m_write_pte(entry, pte, flush_cache);
p2m->stats.mappings[level]++;
*addr += level_size;
return P2M_ONE_PROGRESS;
}
else if ( level == 3 )
return -ENOMEM;
}
/* L3 is always suitably aligned for mapping (handled, above) */
BUG_ON(level == 3);
/*
* If we get here then we failed to allocate a sufficiently
* large contiguous region for this level (which can't be
* L3) or mem_access is in use. Create a page table and
* continue to descend so we try smaller allocations.
*/
rc = p2m_create_table(d, entry, 0, flush_cache);
if ( rc < 0 )
return rc;
return P2M_ONE_DESCEND;
case INSERT:
if ( is_mapping_aligned(*addr, end_gpaddr, *maddr, level_size) &&
/*
* We do not handle replacing an existing table with a superpage
* or when mem_access is in use.
*/
(level == 3 || (!p2m_table(orig_pte) && !p2m->mem_access_enabled)) )
{
rc = p2m_mem_access_radix_set(p2m, paddr_to_pfn(*addr), a);
if ( rc < 0 )
return rc;
/* New mapping is superpage aligned, make it */
pte = mfn_to_p2m_entry(*maddr >> PAGE_SHIFT, mattr, t, a);
if ( level < 3 )
pte.p2m.table = 0; /* Superpage entry */
p2m_write_pte(entry, pte, flush_cache);
*flush |= p2m_valid(orig_pte);
*addr += level_size;
*maddr += level_size;
if ( p2m_valid(orig_pte) )
{
/*
* We can't currently get here for an existing table
* mapping, since we don't handle replacing an
* existing table with a superpage. If we did we would
* need to handle freeing (and accounting) for the bit
* of the p2m tree which we would be about to lop off.
*/
BUG_ON(level < 3 && p2m_table(orig_pte));
if ( level == 3 )
p2m_put_l3_page(orig_pte);
}
else /* New mapping */
p2m->stats.mappings[level]++;
return P2M_ONE_PROGRESS;
}
else
{
