1 files changed, 18 insertions, 4 deletions

diff --git a/drivers/char/agp/nvidia-agp.c b/drivers/char/agp/nvidia-agp.c
index eaceb61ba2dc..0cc1c5baced5 100644
--- a/drivers/char/agp/nvidia-agp.c
+++ b/drivers/char/agp/nvidia-agp.c
@@ -201,10 +201,15 @@ extern int agp_memory_reserved;
 static int nvidia_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
 {
         int i, j;
+        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;
+
         if ((pg_start + mem->page_count) >
                 (nvidia_private.num_active_entries - agp_memory_reserved/PAGE_SIZE))
                 return -EINVAL;
@@ -220,10 +225,13 @@ static int nvidia_insert_memory(struct agp_memory *mem, off_t pg_start, int type
         }
         for (i = 0, j = pg_start; i < mem->page_count; i++, j++) {
                 writel(agp_bridge->driver->mask_memory(agp_bridge,
-                        mem->memory[i], mem->type),
+                        mem->memory[i], mask_type),
                         agp_bridge->gatt_table+nvidia_private.pg_offset+j);
-                readl(agp_bridge->gatt_table+nvidia_private.pg_offset+j);       /* PCI Posting. */
         }
+
+        /* PCI Posting. */
+        readl(agp_bridge->gatt_table+nvidia_private.pg_offset+j - 1);
+
         agp_bridge->driver->tlb_flush(mem);
         return 0;
 }
@@ -233,9 +241,15 @@ static int nvidia_remove_memory(struct agp_memory *mem, off_t pg_start, int type
 {
         int i;
 
-        if ((type != 0) || (mem->type != 0))
+        int mask_type;
+
+        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++)
                 writel(agp_bridge->scratch_page, agp_bridge->gatt_table+nvidia_private.pg_offset+i);