drm: Make drm_local_map use a resource_size_t offset

This changes drm_local_map to use a resource_size for its "offset"
member instead of an unsigned long, thus allowing 32-bit machines
with a >32-bit physical address space to be able to store there
their register or framebuffer addresses when those are above 4G,
such as when using a PCI video card on a recent AMCC 440 SoC.

This patch isn't as "trivial" as it sounds: A few functions needed
to have some unsigned long/int changed to resource_size_t and a few
printk's had to be adjusted.

But also, because userspace isn't capable of passing such offsets,
I had to modify drm_find_matching_map() to ignore the offset passed
in for maps of type _DRM_FRAMEBUFFER or _DRM_REGISTERS.

If we ever support multiple _DRM_FRAMEBUFFER or _DRM_REGISTERS maps
for a given device, we might have to change that trick, but I don't
think that happens on any current driver.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

2 files changed, 11 insertions, 10 deletions

diff --git a/drivers/gpu/drm/mga/mga_dma.c b/drivers/gpu/drm/mga/mga_dma.c
index b49c5ff..7a6bf9f 100644
--- a/drivers/gpu/drm/mga/mga_dma.c
+++ b/drivers/gpu/drm/mga/mga_dma.c
@@ -148,8 +148,8 @@ void mga_do_dma_flush(drm_mga_private_t * dev_priv)
 		primary->space = head - tail;
 	}
 
-	DRM_DEBUG("   head = 0x%06lx\n", head - dev_priv->primary->offset);
-	DRM_DEBUG("   tail = 0x%06lx\n", tail - dev_priv->primary->offset);
+	DRM_DEBUG("   head = 0x%06lx\n", (unsigned long)(head - dev_priv->primary->offset));
+	DRM_DEBUG("   tail = 0x%06lx\n", (unsigned long)(tail - dev_priv->primary->offset));
 	DRM_DEBUG("  space = 0x%06x\n", primary->space);
 
 	mga_flush_write_combine();
@@ -187,7 +187,7 @@ void mga_do_dma_wrap_start(drm_mga_private_t * dev_priv)
 		primary->space = head - dev_priv->primary->offset;
 	}
 
-	DRM_DEBUG("   head = 0x%06lx\n", head - dev_priv->primary->offset);
+	DRM_DEBUG("   head = 0x%06lx\n", (unsigned long)(head - dev_priv->primary->offset));
 	DRM_DEBUG("   tail = 0x%06x\n", primary->tail);
 	DRM_DEBUG("   wrap = %d\n", primary->last_wrap);
 	DRM_DEBUG("  space = 0x%06x\n", primary->space);
@@ -239,7 +239,7 @@ static void mga_freelist_print(struct drm_device * dev)
 	for (entry = dev_priv->head->next; entry; entry = entry->next) {
 		DRM_INFO("   %p   idx=%2d  age=0x%x 0x%06lx\n",
 			 entry, entry->buf->idx, entry->age.head,
-			 entry->age.head - dev_priv->primary->offset);
+			 (unsigned long)(entry->age.head - dev_priv->primary->offset));
 	}
 	DRM_INFO("\n");
 }
@@ -340,10 +340,10 @@ static struct drm_buf *mga_freelist_get(struct drm_device * dev)
 
 	DRM_DEBUG("   tail=0x%06lx %d\n",
 		  tail->age.head ?
-		  tail->age.head - dev_priv->primary->offset : 0,
+		  (unsigned long)(tail->age.head - dev_priv->primary->offset) : 0,
 		  tail->age.wrap);
 	DRM_DEBUG("   head=0x%06lx %d\n",
-		  head - dev_priv->primary->offset, wrap);
+		  (unsigned long)(head - dev_priv->primary->offset), wrap);
 
 	if (TEST_AGE(&tail->age, head, wrap)) {
 		prev = dev_priv->tail->prev;
@@ -366,8 +366,9 @@ int mga_freelist_put(struct drm_device * dev, struct drm_buf * buf)
 	drm_mga_freelist_t *head, *entry, *prev;
 
 	DRM_DEBUG("age=0x%06lx wrap=%d\n",
-		  buf_priv->list_entry->age.head -
-		  dev_priv->primary->offset, buf_priv->list_entry->age.wrap);
+		  (unsigned long)(buf_priv->list_entry->age.head -
+				  dev_priv->primary->offset),
+		  buf_priv->list_entry->age.wrap);
 
 	entry = buf_priv->list_entry;
 	head = dev_priv->head;
diff --git a/drivers/gpu/drm/mga/mga_drv.h b/drivers/gpu/drm/mga/mga_drv.h
index 6bf4de9..3d264f28 100644
--- a/drivers/gpu/drm/mga/mga_drv.h
+++ b/drivers/gpu/drm/mga/mga_drv.h
@@ -317,8 +317,8 @@ do {									\
 		DRM_INFO( "\n" );					\
 		DRM_INFO( "   tail=0x%06x head=0x%06lx\n",		\
 			  dev_priv->prim.tail,				\
-			  MGA_READ( MGA_PRIMADDRESS ) -			\
-			  dev_priv->primary->offset );			\
+			  (unsigned long)(MGA_READ(MGA_PRIMADDRESS) -	\
+					  dev_priv->primary->offset));	\
 	}								\
 	if ( !test_bit( 0, &dev_priv->prim.wrapped ) ) {		\
 		if ( dev_priv->prim.space <				\