@@ -851,17 +851,9 @@ static int p2m_mem_access_radix_set(struct p2m_domain *p2m, gfn_t gfn,
return rc;
}
-/*
- * Put any references on the single 4K page referenced by pte.
- * TODO: Handle superpages, for now we only take special references for leaf
- * pages (specifically foreign ones, which can't be super mapped today).
- */
-static void p2m_put_l3_page(const lpae_t pte)
+/* Put any references on the single 4K page referenced by mfn. */
+static void p2m_put_l3_page(mfn_t mfn, unsigned type)
{
- mfn_t mfn = lpae_get_mfn(pte);
-
- ASSERT(p2m_is_valid(pte));
-
/*
* TODO: Handle other p2m types
*
@@ -869,16 +861,53 @@ static void p2m_put_l3_page(const lpae_t pte)
* flush the TLBs if the page is reallocated before the end of
* this loop.
*/
- if ( p2m_is_foreign(pte.p2m.type) )
+ if ( p2m_is_foreign(type) )
{
ASSERT(mfn_valid(mfn));
put_page(mfn_to_page(mfn));
}
/* Detect the xenheap page and mark the stored GFN as invalid. */
- else if ( p2m_is_ram(pte.p2m.type) && is_xen_heap_mfn(mfn) )
+ else if ( p2m_is_ram(type) && is_xen_heap_mfn(mfn) )
page_set_xenheap_gfn(mfn_to_page(mfn), INVALID_GFN);
}
+/* Put any references on the superpage referenced by mfn. */
+static void p2m_put_superpage(mfn_t mfn, unsigned int next_level, unsigned type)
+{
+ unsigned int i;
+ unsigned int level_order = XEN_PT_LEVEL_ORDER(next_level);
+
+ for ( i = 0; i < XEN_PT_LPAE_ENTRIES; i++ )
+ {
+ if ( next_level == 3 )
+ p2m_put_l3_page(mfn, type);
+ else
+ p2m_put_superpage(mfn, next_level + 1, type);
+
+ mfn = mfn_add(mfn, 1 << level_order);
+ }
+}
+
+/* Put any references on the page referenced by pte. */
+static void p2m_put_page(const lpae_t pte, unsigned int level)
+{
+ mfn_t mfn = lpae_get_mfn(pte);
+
+ ASSERT(p2m_is_valid(pte));
+
+ /*
+ * We are either having a first level 1G superpage or a
+ * second level 2M superpage.
+ */
+ if ( p2m_is_superpage(pte, level) )
+ return p2m_put_superpage(mfn, level + 1, pte.p2m.type);
+ else
+ {
+ ASSERT(level == 3);
+ return p2m_put_l3_page(mfn, pte.p2m.type);
+ }
+}
+
/* Free lpae sub-tree behind an entry */
static void p2m_free_entry(struct p2m_domain *p2m,
lpae_t entry, unsigned int level)
@@ -907,9 +936,8 @@ static void p2m_free_entry(struct p2m_domain *p2m,
#endif
p2m->stats.mappings[level]--;
- /* Nothing to do if the entry is a super-page. */
- if ( level == 3 )
- p2m_put_l3_page(entry);
+ p2m_put_page(entry, level);
+
return;
}
@@ -1752,7 +1780,7 @@ void p2m_final_teardown(struct domain *d)
* p2m_final_teardown() is called either after domain_relinquish_resources()
* where relinquish_p2m_mapping() has been called, or from failure path of
* domain_create()/arch_domain_create() where mappings that require
- * p2m_put_l3_page() should never be created. For the latter case, also see
+ * p2m_put_page() should never be created. For the latter case, also see
* comment on top of the p2m_set_entry() for more info.
*/
We are doing foreign memory mapping for static shared memory, and there is a great possibility that it could be super mapped. But today, p2m_put_l3_page could not handle superpages. This commits implements a new function p2m_put_superpage to handle superpages, specifically for helping put extra references for foreign superpages. Signed-off-by: Penny Zheng <penny.zheng@arm.com> --- v1 -> v2: - new commit --- xen/arch/arm/p2m.c | 60 +++++++++++++++++++++++++++++++++------------- 1 file changed, 44 insertions(+), 16 deletions(-)