1 files changed, 14 insertions, 4 deletions

diff --git a/drivers/char/agp/ati-agp.c b/drivers/char/agp/ati-agp.c
index 4d38baa209f5..33656e144cc5 100644
--- a/drivers/char/agp/ati-agp.c
+++ b/drivers/char/agp/ati-agp.c
@@ -269,12 +269,17 @@ static int ati_insert_memory(struct agp_memory * mem,
         int i, j, num_entries;
         unsigned long __iomem *cur_gatt;
         unsigned long addr;
+        int mask_type;
 
         num_entries = A_SIZE_LVL2(agp_bridge->current_size)->num_entries;
 
-        if (type != 0 || mem->type != 0)
+        mask_type = agp_generic_type_to_mask_type(mem->bridge, type);
+        if (mask_type != 0 || type != mem->type)
                 return -EINVAL;
 
+        if (mem->page_count == 0)
+                return 0;
+
         if ((pg_start + mem->page_count) > num_entries)
                 return -EINVAL;
 
@@ -299,8 +304,8 @@ static int ati_insert_memory(struct agp_memory * mem,
                 writel(agp_bridge->driver->mask_memory(agp_bridge,      
                                                        mem->pages[i], mem->type),
                        cur_gatt+GET_GATT_OFF(addr));
-                readl(cur_gatt+GET_GATT_OFF(addr));     /* PCI Posting. */
         }
+        readl(GET_GATT(agp_bridge->gart_bus_addr)); /* PCI posting */
         agp_bridge->driver->tlb_flush(mem);
         return 0;
 }
@@ -311,17 +316,22 @@ static int ati_remove_memory(struct agp_memory * mem, off_t pg_start,
         int i;
         unsigned long __iomem *cur_gatt;
         unsigned long addr;
+        int mask_type;
 
-        if (type != 0 || mem->type != 0)
+        mask_type = agp_generic_type_to_mask_type(mem->bridge, type);
+        if (mask_type != 0 || type != mem->type)
                 return -EINVAL;
 
+        if (mem->page_count == 0)
+                return 0;
+
         for (i = pg_start; i < (mem->page_count + pg_start); i++) {
                 addr = (i * PAGE_SIZE) + agp_bridge->gart_bus_addr;
                 cur_gatt = GET_GATT(addr);
                 writel(agp_bridge->scratch_page, cur_gatt+GET_GATT_OFF(addr));
-                readl(cur_gatt+GET_GATT_OFF(addr)); /* PCI Posting. */
         }
 
+        readl(GET_GATT(agp_bridge->gart_bus_addr)); /* PCI posting */
         agp_bridge->driver->tlb_flush(mem);
         return 0;
 }