diff mbox

[v3,3/3] x86/p2m-pt: pass level instead of page type to p2m_next_level()

Message ID 598DCB71020000780016EE13@prv-mh.provo.novell.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jan Beulich Aug. 11, 2017, 1:21 p.m. UTC 
This in turn calls for p2m_alloc_ptp() also being passed the numeric
level.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
---
v2: New.
---
Question is whether passing the level to p2m_alloc_ptp() is really all
that useful: p2m-ept.c's passes zero only anyway, and p2m.c's uniform
passing of 4 doesn't necessarily match reality afaict.
diff mbox

Patch

--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -569,7 +569,7 @@  int p2m_set_entry(struct p2m_domain *p2m
     return rc;
 }
 
-mfn_t p2m_alloc_ptp(struct p2m_domain *p2m, unsigned long type)
+mfn_t p2m_alloc_ptp(struct p2m_domain *p2m, unsigned int level)
 {
     struct page_info *pg;
 
@@ -581,7 +581,10 @@  mfn_t p2m_alloc_ptp(struct p2m_domain *p
         return INVALID_MFN;
 
     page_list_add_tail(pg, &p2m->pages);
-    pg->u.inuse.type_info = type | 1 | PGT_validated;
+    BUILD_BUG_ON(PGT_l1_page_table * 2 != PGT_l2_page_table);
+    BUILD_BUG_ON(PGT_l1_page_table * 3 != PGT_l3_page_table);
+    BUILD_BUG_ON(PGT_l1_page_table * 4 != PGT_l4_page_table);
+    pg->u.inuse.type_info = (PGT_l1_page_table * level) | 1 | PGT_validated;
 
     return page_to_mfn(pg);
 }
@@ -632,7 +635,7 @@  int p2m_alloc_table(struct p2m_domain *p
 
     P2M_PRINTK("allocating p2m table\n");
 
-    top_mfn = p2m_alloc_ptp(p2m, PGT_l4_page_table);
+    top_mfn = p2m_alloc_ptp(p2m, 4);
     if ( mfn_eq(top_mfn, INVALID_MFN) )
     {
         p2m_unlock(p2m);
--- a/xen/arch/x86/mm/p2m-pt.c
+++ b/xen/arch/x86/mm/p2m-pt.c
@@ -71,12 +71,6 @@ 
 #define needs_recalc(level, ent) _needs_recalc(level##e_get_flags(ent))
 #define valid_recalc(level, ent) (!(level##e_get_flags(ent) & _PAGE_ACCESSED))
 
-static const unsigned long pgt[] = {
-    PGT_l1_page_table,
-    PGT_l2_page_table,
-    PGT_l3_page_table
-};
-
 static unsigned long p2m_type_to_flags(const struct p2m_domain *p2m,
                                        p2m_type_t t,
                                        mfn_t mfn,
@@ -189,7 +183,7 @@  static void p2m_add_iommu_flags(l1_pgent
 static int
 p2m_next_level(struct p2m_domain *p2m, void **table,
                unsigned long *gfn_remainder, unsigned long gfn, u32 shift,
-               u32 max, unsigned long type, bool_t unmap)
+               u32 max, unsigned int level, bool_t unmap)
 {
     l1_pgentry_t *p2m_entry, new_entry;
     void *next;
@@ -204,30 +198,15 @@  p2m_next_level(struct p2m_domain *p2m, v
     /* PoD/paging: Not present doesn't imply empty. */
     if ( !flags )
     {
-        mfn_t mfn = p2m_alloc_ptp(p2m, type);
+        mfn_t mfn = p2m_alloc_ptp(p2m, level);
 
         if ( mfn_eq(mfn, INVALID_MFN) )
             return -ENOMEM;
 
         new_entry = l1e_from_pfn(mfn_x(mfn), P2M_BASE_FLAGS | _PAGE_RW);
 
-        switch ( type ) {
-        case PGT_l3_page_table:
-            p2m_add_iommu_flags(&new_entry, 3, IOMMUF_readable|IOMMUF_writable);
-            p2m->write_p2m_entry(p2m, gfn, p2m_entry, new_entry, 4);
-            break;
-        case PGT_l2_page_table:
-            p2m_add_iommu_flags(&new_entry, 2, IOMMUF_readable|IOMMUF_writable);
-            p2m->write_p2m_entry(p2m, gfn, p2m_entry, new_entry, 3);
-            break;
-        case PGT_l1_page_table:
-            p2m_add_iommu_flags(&new_entry, 1, IOMMUF_readable|IOMMUF_writable);
-            p2m->write_p2m_entry(p2m, gfn, p2m_entry, new_entry, 2);
-            break;
-        default:
-            BUG();
-            break;
-        }
+        p2m_add_iommu_flags(&new_entry, level, IOMMUF_readable|IOMMUF_writable);
+        p2m->write_p2m_entry(p2m, gfn, p2m_entry, new_entry, level + 1);
     }
     else if ( flags & _PAGE_PSE )
     {
@@ -235,15 +214,14 @@  p2m_next_level(struct p2m_domain *p2m, v
         unsigned long pfn = l1e_get_pfn(*p2m_entry);
         mfn_t mfn;
         l1_pgentry_t *l1_entry;
-        unsigned int i, level;
+        unsigned int i;
 
-        switch ( type )
+        switch ( level )
         {
-        case PGT_l2_page_table:
-            level = 2;
+        case 2:
             break;
 
-        case PGT_l1_page_table:
+        case 1:
             /*
              * New splintered mappings inherit the flags of the old superpage,
              * with a little reorganisation for the _PAGE_PSE_PAT bit.
@@ -252,8 +230,6 @@  p2m_next_level(struct p2m_domain *p2m, v
                 pfn -= 1;            /* Clear it; _PAGE_PSE becomes _PAGE_PAT */
             else
                 flags &= ~_PAGE_PSE; /* Clear _PAGE_PSE (== _PAGE_PAT) */
-
-            level = 1;
             break;
 
         default:
@@ -261,7 +237,7 @@  p2m_next_level(struct p2m_domain *p2m, v
             return -EINVAL;
         }
 
-        mfn = p2m_alloc_ptp(p2m, type);
+        mfn = p2m_alloc_ptp(p2m, level);
         if ( mfn_eq(mfn, INVALID_MFN) )
             return -ENOMEM;
 
@@ -331,7 +307,7 @@  static int p2m_pt_set_recalc_range(struc
 
         err = p2m_next_level(p2m, &table, &gfn_remainder, first_gfn,
                              i * PAGETABLE_ORDER, 1 << PAGETABLE_ORDER,
-                             pgt[i - 1], 1);
+                             i, 1);
         if ( err )
             goto out;
     }
@@ -399,7 +375,7 @@  static int do_recalc(struct p2m_domain *
 
         err = p2m_next_level(p2m, &table, &gfn_remainder, gfn,
                              level * PAGETABLE_ORDER, 1 << PAGETABLE_ORDER,
-                             pgt[level - 1], 0);
+                             level, 0);
         if ( err )
             goto out;
 
@@ -563,7 +539,7 @@  p2m_pt_set_entry(struct p2m_domain *p2m,
     table = map_domain_page(pagetable_get_mfn(p2m_get_pagetable(p2m)));
     rc = p2m_next_level(p2m, &table, &gfn_remainder, gfn,
                         L4_PAGETABLE_SHIFT - PAGE_SHIFT,
-                        L4_PAGETABLE_ENTRIES, PGT_l3_page_table, 1);
+                        L4_PAGETABLE_ENTRIES, 3, 1);
     if ( rc )
         goto out;
 
@@ -611,7 +587,7 @@  p2m_pt_set_entry(struct p2m_domain *p2m,
     {
         rc = p2m_next_level(p2m, &table, &gfn_remainder, gfn,
                             L3_PAGETABLE_SHIFT - PAGE_SHIFT,
-                            L3_PAGETABLE_ENTRIES, PGT_l2_page_table, 1);
+                            L3_PAGETABLE_ENTRIES, 2, 1);
         if ( rc )
             goto out;
     }
@@ -622,7 +598,7 @@  p2m_pt_set_entry(struct p2m_domain *p2m,
 
         rc = p2m_next_level(p2m, &table, &gfn_remainder, gfn,
                             L2_PAGETABLE_SHIFT - PAGE_SHIFT,
-                            L2_PAGETABLE_ENTRIES, PGT_l1_page_table, 1);
+                            L2_PAGETABLE_ENTRIES, 1, 1);
         if ( rc )
             goto out;
 
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -684,7 +684,7 @@  void p2m_mem_paging_resume(struct domain
  * Internal functions, only called by other p2m code
  */
 
-mfn_t p2m_alloc_ptp(struct p2m_domain *p2m, unsigned long type);
+mfn_t p2m_alloc_ptp(struct p2m_domain *p2m, unsigned int level);
 void p2m_free_ptp(struct p2m_domain *p2m, struct page_info *pg);
 
 /* Directly set a p2m entry: only for use by p2m code. Does not need