@@ -278,8 +278,7 @@ static p2m_access_t p2m_mem_access_radix_get(struct p2m_domain *p2m, gfn_t gfn)
#define GUEST_TABLE_SUPER_PAGE 1
#define GUEST_TABLE_NORMAL_PAGE 2
-static int p2m_create_table(struct p2m_domain *p2m, lpae_t *entry,
- int level_shift);
+static int p2m_create_table(struct p2m_domain *p2m, lpae_t *entry);
/*
* Take the currently mapped table, find the corresponding GFN entry,
@@ -310,7 +309,7 @@ static int p2m_next_level(struct p2m_domain *p2m, bool read_only,
if ( read_only )
return GUEST_TABLE_MAP_FAILED;
- ret = p2m_create_table(p2m, entry, /* not used */ ~0);
+ ret = p2m_create_table(p2m, entry);
if ( ret )
return GUEST_TABLE_MAP_FAILED;
}
@@ -575,25 +574,14 @@ static inline void p2m_remove_pte(lpae_t *p, bool clean_pte)
p2m_write_pte(p, pte, clean_pte);
}
-/*
- * Allocate a new page table page and hook it in via the given entry.
- * apply_one_level relies on this returning 0 on success
- * and -ve on failure.
- *
- * If the existing entry is present then it must be a mapping and not
- * a table and it will be shattered into the next level down.
- *
- * level_shift is the number of bits at the level we want to create.
- */
-static int p2m_create_table(struct p2m_domain *p2m, lpae_t *entry,
- int level_shift)
+/* Allocate a new page table page and hook it in via the given entry. */
+static int p2m_create_table(struct p2m_domain *p2m, lpae_t *entry)
{
struct page_info *page;
lpae_t *p;
lpae_t pte;
- int splitting = p2m_valid(*entry);
- BUG_ON(p2m_table(*entry));
+ ASSERT(!p2m_valid(*entry));
page = alloc_domheap_page(NULL, 0);
if ( page == NULL )
@@ -602,39 +590,7 @@ static int p2m_create_table(struct p2m_domain *p2m, lpae_t *entry,
page_list_add(page, &p2m->pages);
p = __map_domain_page(page);
- if ( splitting )
- {
- mfn_t mfn = _mfn(entry->p2m.base);
- int i;
-
- /*
- * We are either splitting a first level 1G page into 512 second level
- * 2M pages, or a second level 2M page into 512 third level 4K pages.
- */
- for ( i=0 ; i < LPAE_ENTRIES; i++ )
- {
- /*
- * Use the content of the superpage entry and override
- * the necessary fields. So the correct permissions are
- * kept.
- */
- pte = *entry;
- pte.p2m.base = mfn_x(mfn_add(mfn,
- i << (level_shift - LPAE_SHIFT)));
-
- /*
- * First and second level super pages set p2m.table = 0, but
- * third level entries set table = 1.
- */
- pte.p2m.table = !(level_shift - LPAE_SHIFT);
-
- write_pte(&p[i], pte);
- }
-
- page->u.inuse.p2m_refcount = LPAE_ENTRIES;
- }
- else
- clear_page(p);
+ clear_page(p);
if ( p2m->clean_pte )
clean_dcache_va_range(p, PAGE_SIZE);
The helper p2m_create_table is only called to create a brand new table. Signed-off-by: Julien Grall <julien.grall@arm.com> Reviewd-by: Stefano Stabellini <sstabelini@kernel.org> --- Changes in v2: - Add Stefano's reviewed-by --- xen/arch/arm/p2m.c | 56 ++++++------------------------------------------------ 1 file changed, 6 insertions(+), 50 deletions(-)