1 files changed, 22 insertions, 10 deletions

diff --git a/hw/xen/xen-mapcache.c b/hw/xen/xen-mapcache.c
index 698b5c53ed..e31d379702 100644
--- a/hw/xen/xen-mapcache.c
+++ b/hw/xen/xen-mapcache.c
@@ -75,7 +75,8 @@ typedef struct MapCache {
 } MapCache;
 
 static MapCache *mapcache;
-static MapCache *mapcache_grants;
+static MapCache *mapcache_grants_ro;
+static MapCache *mapcache_grants_rw;
 static xengnttab_handle *xen_region_gnttabdev;
 
 static inline void mapcache_lock(MapCache *mc)
@@ -176,9 +177,12 @@ void xen_map_cache_init(phys_offset_to_gaddr_t f, void *opaque)
      * Grant mappings must use XC_PAGE_SIZE granularity since we can't
      * map anything beyond the number of pages granted to us.
      */
-    mapcache_grants = xen_map_cache_init_single(f, opaque,
-                                                XC_PAGE_SHIFT,
-                                                max_mcache_size);
+    mapcache_grants_ro = xen_map_cache_init_single(f, opaque,
+                                                   XC_PAGE_SHIFT,
+                                                   max_mcache_size);
+    mapcache_grants_rw = xen_map_cache_init_single(f, opaque,
+                                                   XC_PAGE_SHIFT,
+                                                   max_mcache_size);
 
     setrlimit(RLIMIT_AS, &rlimit_as);
 }
@@ -376,12 +380,12 @@ tryagain:
 
     entry = &mc->entry[address_index % mc->nr_buckets];
 
-    while (entry && (lock || entry->lock) && entry->vaddr_base &&
-            (entry->paddr_index != address_index || entry->size != cache_size ||
+    while (entry && (!entry->vaddr_base ||
+            entry->paddr_index != address_index || entry->size != cache_size ||
              !test_bits(address_offset >> XC_PAGE_SHIFT,
                  test_bit_size >> XC_PAGE_SHIFT,
                  entry->valid_mapping))) {
-        if (!free_entry && !entry->lock) {
+        if (!free_entry && (!entry->lock || !entry->vaddr_base)) {
             free_entry = entry;
             free_pentry = pentry;
         }
@@ -456,9 +460,13 @@ uint8_t *xen_map_cache(MemoryRegion *mr,
                        bool is_write)
 {
     bool grant = xen_mr_is_grants(mr);
-    MapCache *mc = grant ? mapcache_grants : mapcache;
+    MapCache *mc = mapcache;
     uint8_t *p;
 
+    if (grant) {
+        mc = is_write ? mapcache_grants_rw : mapcache_grants_ro;
+    }
+
     if (grant && !lock) {
         /*
          * Grants are only supported via address_space_map(). Anything
@@ -523,7 +531,10 @@ ram_addr_t xen_ram_addr_from_mapcache(void *ptr)
 
     addr = xen_ram_addr_from_mapcache_single(mapcache, ptr);
     if (addr == RAM_ADDR_INVALID) {
-        addr = xen_ram_addr_from_mapcache_single(mapcache_grants, ptr);
+        addr = xen_ram_addr_from_mapcache_single(mapcache_grants_ro, ptr);
+    }
+    if (addr == RAM_ADDR_INVALID) {
+        addr = xen_ram_addr_from_mapcache_single(mapcache_grants_rw, ptr);
     }
 
     return addr;
@@ -626,7 +637,8 @@ static void xen_invalidate_map_cache_entry_single(MapCache *mc, uint8_t *buffer)
 static void xen_invalidate_map_cache_entry_all(uint8_t *buffer)
 {
     xen_invalidate_map_cache_entry_single(mapcache, buffer);
-    xen_invalidate_map_cache_entry_single(mapcache_grants, buffer);
+    xen_invalidate_map_cache_entry_single(mapcache_grants_ro, buffer);
+    xen_invalidate_map_cache_entry_single(mapcache_grants_rw, buffer);
 }
 
 static void xen_invalidate_map_cache_entry_bh(void *opaque)