When static domain populates memory through populate_physmap on runtime,
other than allocating from heap, it shall retrieve reserved pages from
resv_page_list to make sure that guest RAM is still restricted in statically
configured memory regions. And this commit introduces a new helper
acquire_reserved_page to make it work.
Signed-off-by: Penny Zheng <penny.zh...@arm.com>
---
v2 changes:
- introduce acquire_reserved_page to retrieve reserved pages from
resv_page_list
- forbid non-zero-order requests in populate_physmap
- let is_domain_static return ((void)(d), false) on x86
---
xen/common/memory.c | 29 +++++++++++++++++++++++++++++
xen/common/page_alloc.c | 28 ++++++++++++++++++++++++++++
xen/include/xen/mm.h | 1 +
3 files changed, 58 insertions(+)
diff --git a/xen/common/memory.c b/xen/common/memory.c
index 69b0cd1e50..f7729dfa5c 100644
--- a/xen/common/memory.c
+++ b/xen/common/memory.c
@@ -35,6 +35,10 @@
#include <asm/guest.h>
#endif
+#ifndef is_domain_static
+#define is_domain_static(d) ((void)(d), false)
+#endif
+
struct memop_args {
/* INPUT */
struct domain *domain; /* Domain to be affected. */
@@ -245,6 +249,31 @@ static void populate_physmap(struct memop_args *a)
mfn = _mfn(gpfn);
}
+#ifdef CONFIG_STATIC_MEMORY
+ else if ( is_domain_static(d) )
+ {
+ /*
+ * No easy way to guarantee the retreived pages are contiguous,
+ * so forbid non-zero-order requests here.
+ */
+ if ( a->extent_order != 0 )
+ {
+ gdprintk(XENLOG_INFO,
+ "Could not allocate non-zero-order pages for
static %pd.\n.",
+ d);
+ goto out;
+ }
+
+ mfn = acquire_reserved_page(d, a->memflags);
+ if ( mfn_eq(mfn, INVALID_MFN) )
+ {
+ gdprintk(XENLOG_INFO,
+ "%pd: failed to retrieve a reserved page.\n.",
+ d);
+ goto out;
+ }
+ }
+#endif
else
{
page = alloc_domheap_pages(d, a->extent_order, a->memflags);
diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index 8ba38bca9a..759d612eb8 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -2770,6 +2770,34 @@ int __init acquire_domstatic_pages(struct domain *d,
mfn_t smfn,
return 0;
}
+
+/*
+ * Acquire a page from reserved page list(resv_page_list), when populating
+ * memory for static domain on runtime.
+ */
+mfn_t acquire_reserved_page(struct domain *d, unsigned int memflags)
+{
+ struct page_info *page;
+ mfn_t smfn;
+
+ /* Acquire a page from reserved page list(resv_page_list). */
+ page = page_list_remove_head(&d->resv_page_list);
+ if ( unlikely(!page) )
+ {
+ printk(XENLOG_ERR
+ "%pd: failed to acquire a reserved page %"PRI_mfn".\n",
+ d, mfn_x(page_to_mfn(page)));
+ return INVALID_MFN;
+ }
+ d->resv_pages--;
+
+ smfn = page_to_mfn(page);
+
+ if ( acquire_domstatic_pages(d, smfn, 1, memflags) )
+ return INVALID_MFN;
+
+ return smfn;
+}
#endif
/*
diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h
index 3be754da92..6ef5a6adcd 100644
--- a/xen/include/xen/mm.h
+++ b/xen/include/xen/mm.h
@@ -91,6 +91,7 @@ void free_staticmem_pages(struct page_info *pg, unsigned long
nr_mfns,
bool need_scrub);
int acquire_domstatic_pages(struct domain *d, mfn_t smfn, unsigned int nr_mfns,
unsigned int memflags);
+mfn_t acquire_reserved_page(struct domain *d, unsigned int memflags);
#endif
/* Map machine page range in Xen virtual address space. */
--
2.25.1
