[PATCH 1/3] xen/arm: p2m: extend create_p2m_entries to support read-only mapping

[Julien Grall <julien.grall@linaro.org>]

Signed-off-by: Julien Grall <julien.grall@linaro.org>
---
 xen/arch/arm/p2m.c         | 19 +++++++++++--------
 xen/include/asm-arm/page.h |  5 +++--
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
index 2d09fef..fdbb07b 100644
--- a/xen/arch/arm/p2m.c
+++ b/xen/arch/arm/p2m.c
@@ -111,7 +111,7 @@ static int p2m_create_table(struct domain *d,
     clear_page(p);
     unmap_domain_page(p);
 
-    pte = mfn_to_p2m_entry(page_to_mfn(page), MATTR_MEM);
+    pte = mfn_to_p2m_entry(page_to_mfn(page), MATTR_MEM, 1);
 
     write_pte(entry, pte);
 
@@ -129,7 +129,8 @@ static int create_p2m_entries(struct domain *d,
                      paddr_t start_gpaddr,
                      paddr_t end_gpaddr,
                      paddr_t maddr,
-                     int mattr)
+                     int mattr,
+                     bool_t rw)
 {
     int rc, flush;
     struct p2m_domain *p2m = &d->arch.p2m;
@@ -201,14 +202,15 @@ static int create_p2m_entries(struct domain *d,
                         goto out;
                     }
 
-                    pte = mfn_to_p2m_entry(page_to_mfn(page), mattr);
+                    pte = mfn_to_p2m_entry(page_to_mfn(page), mattr, rw);
 
                     write_pte(&third[third_table_offset(addr)], pte);
                 }
                 break;
             case INSERT:
                 {
-                    lpae_t pte = mfn_to_p2m_entry(maddr >> PAGE_SHIFT, mattr);
+                    lpae_t pte = mfn_to_p2m_entry(maddr >> PAGE_SHIFT, 
+                                                  mattr, rw);
                     write_pte(&third[third_table_offset(addr)], pte);
                     maddr += PAGE_SIZE;
                 }
@@ -243,7 +245,7 @@ int p2m_populate_ram(struct domain *d,
                      paddr_t start,
                      paddr_t end)
 {
-    return create_p2m_entries(d, ALLOCATE, start, end, 0, MATTR_MEM);
+    return create_p2m_entries(d, ALLOCATE, start, end, 0, MATTR_MEM, 1);
 }
 
 int map_mmio_regions(struct domain *d,
@@ -251,7 +253,8 @@ int map_mmio_regions(struct domain *d,
                      paddr_t end_gaddr,
                      paddr_t maddr)
 {
-    return create_p2m_entries(d, INSERT, start_gaddr, end_gaddr, maddr, MATTR_DEV);
+    return create_p2m_entries(d, INSERT, start_gaddr, end_gaddr,
+                              maddr, MATTR_DEV, 1);
 }
 
 int guest_physmap_add_page(struct domain *d,
@@ -261,7 +264,7 @@ int guest_physmap_add_page(struct domain *d,
 {
     return create_p2m_entries(d, INSERT, gpfn << PAGE_SHIFT,
                               (gpfn + (1<<page_order)) << PAGE_SHIFT,
-                              mfn << PAGE_SHIFT, MATTR_MEM);
+                              mfn << PAGE_SHIFT, MATTR_MEM, 1);
 }
 
 void guest_physmap_remove_page(struct domain *d,
@@ -270,7 +273,7 @@ void guest_physmap_remove_page(struct domain *d,
 {
     create_p2m_entries(d, REMOVE, gpfn << PAGE_SHIFT,
                        (gpfn + (1<<page_order)) << PAGE_SHIFT,
-                       mfn << PAGE_SHIFT, MATTR_MEM);
+                       mfn << PAGE_SHIFT, MATTR_MEM, 0);
 }
 
 int p2m_alloc_table(struct domain *d)
diff --git a/xen/include/asm-arm/page.h b/xen/include/asm-arm/page.h
index 3d0f8a9..3e9dda7 100644
--- a/xen/include/asm-arm/page.h
+++ b/xen/include/asm-arm/page.h
@@ -213,14 +213,15 @@ static inline lpae_t mfn_to_xen_entry(unsigned long mfn)
     return e;
 }
 
-static inline lpae_t mfn_to_p2m_entry(unsigned long mfn, unsigned int mattr)
+static inline lpae_t mfn_to_p2m_entry(unsigned long mfn, unsigned int mattr,
+                                      bool_t rw)
 {
     paddr_t pa = ((paddr_t) mfn) << PAGE_SHIFT;
     lpae_t e = (lpae_t) {
         .p2m.xn = 0,
         .p2m.af = 1,
         .p2m.sh = LPAE_SH_OUTER,
-        .p2m.write = 1,
+        .p2m.write = !!rw,
         .p2m.read = 1,
         .p2m.mattr = mattr,
         .p2m.table = 1,
-- 
1.8.3.1