drm/vmwgfx: Use the linux DMA api to get valid device addresses of pages
The code handles three different cases:
1) physical page addresses. The ttm page array is used.
2) DMA subsystem addresses. A scatter-gather list is used.
3) Coherent pages. The ttm dma pool is used, together with the dma_ttm
array os dma_addr_t
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
index 1a0bf07..6d09523 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
@@ -32,9 +32,11 @@
#define VMW_PPN_SIZE (sizeof(unsigned long))
/* A future safe maximum remap size. */
#define VMW_PPN_PER_REMAP ((31 * 1024) / VMW_PPN_SIZE)
+#define DMA_ADDR_INVALID ((dma_addr_t) 0)
+#define DMA_PAGE_INVALID 0UL
static int vmw_gmr2_bind(struct vmw_private *dev_priv,
- struct page *pages[],
+ struct vmw_piter *iter,
unsigned long num_pages,
int gmr_id)
{
@@ -81,11 +83,13 @@
for (i = 0; i < nr; ++i) {
if (VMW_PPN_SIZE <= 4)
- *cmd = page_to_pfn(*pages++);
+ *cmd = vmw_piter_dma_addr(iter) >> PAGE_SHIFT;
else
- *((uint64_t *)cmd) = page_to_pfn(*pages++);
+ *((uint64_t *)cmd) = vmw_piter_dma_addr(iter) >>
+ PAGE_SHIFT;
cmd += VMW_PPN_SIZE / sizeof(*cmd);
+ vmw_piter_next(iter);
}
num_pages -= nr;
@@ -120,22 +124,54 @@
vmw_fifo_commit(dev_priv, define_size);
}
+
+static void vmw_gmr_free_descriptors(struct device *dev, dma_addr_t desc_dma,
+ struct list_head *desc_pages)
+{
+ struct page *page, *next;
+ struct svga_guest_mem_descriptor *page_virtual;
+ unsigned int desc_per_page = PAGE_SIZE /
+ sizeof(struct svga_guest_mem_descriptor) - 1;
+
+ if (list_empty(desc_pages))
+ return;
+
+ list_for_each_entry_safe(page, next, desc_pages, lru) {
+ list_del_init(&page->lru);
+
+ if (likely(desc_dma != DMA_ADDR_INVALID)) {
+ dma_unmap_page(dev, desc_dma, PAGE_SIZE,
+ DMA_TO_DEVICE);
+ }
+
+ page_virtual = kmap_atomic(page);
+ desc_dma = page_virtual[desc_per_page].ppn << PAGE_SHIFT;
+ kunmap_atomic(page_virtual);
+
+ __free_page(page);
+ }
+}
+
/**
* FIXME: Adjust to the ttm lowmem / highmem storage to minimize
* the number of used descriptors.
+ *
*/
-static int vmw_gmr_build_descriptors(struct list_head *desc_pages,
- struct page *pages[],
- unsigned long num_pages)
+static int vmw_gmr_build_descriptors(struct device *dev,
+ struct list_head *desc_pages,
+ struct vmw_piter *iter,
+ unsigned long num_pages,
+ dma_addr_t *first_dma)
{
- struct page *page, *next;
+ struct page *page;
struct svga_guest_mem_descriptor *page_virtual = NULL;
struct svga_guest_mem_descriptor *desc_virtual = NULL;
unsigned int desc_per_page;
unsigned long prev_pfn;
unsigned long pfn;
int ret;
+ dma_addr_t desc_dma;
desc_per_page = PAGE_SIZE /
sizeof(struct svga_guest_mem_descriptor) - 1;
@@ -148,23 +184,12 @@
}
list_add_tail(&page->lru, desc_pages);
-
- /*
- * Point previous page terminating descriptor to this
- * page before unmapping it.
- */
-
- if (likely(page_virtual != NULL)) {
- desc_virtual->ppn = page_to_pfn(page);
- kunmap_atomic(page_virtual);
- }
-
page_virtual = kmap_atomic(page);
desc_virtual = page_virtual - 1;
prev_pfn = ~(0UL);
while (likely(num_pages != 0)) {
- pfn = page_to_pfn(*pages);
+ pfn = vmw_piter_dma_addr(iter) >> PAGE_SHIFT;
if (pfn != prev_pfn + 1) {
@@ -181,104 +206,81 @@
}
prev_pfn = pfn;
--num_pages;
- ++pages;
+ vmw_piter_next(iter);
}
- (++desc_virtual)->ppn = cpu_to_le32(0);
+ (++desc_virtual)->ppn = DMA_PAGE_INVALID;
desc_virtual->num_pages = cpu_to_le32(0);
+ kunmap_atomic(page_virtual);
}
- if (likely(page_virtual != NULL))
+ desc_dma = 0;
+ list_for_each_entry_reverse(page, desc_pages, lru) {
+ page_virtual = kmap_atomic(page);
+ page_virtual[desc_per_page].ppn = desc_dma >> PAGE_SHIFT;
kunmap_atomic(page_virtual);
+ desc_dma = dma_map_page(dev, page, 0, PAGE_SIZE,
+ DMA_TO_DEVICE);
+
+ if (unlikely(dma_mapping_error(dev, desc_dma)))
+ goto out_err;
+ }
+ *first_dma = desc_dma;
return 0;
out_err:
- list_for_each_entry_safe(page, next, desc_pages, lru) {
- list_del_init(&page->lru);
- __free_page(page);
- }
+ vmw_gmr_free_descriptors(dev, DMA_ADDR_INVALID, desc_pages);
return ret;
}
-static inline void vmw_gmr_free_descriptors(struct list_head *desc_pages)
-{
- struct page *page, *next;
-
- list_for_each_entry_safe(page, next, desc_pages, lru) {
- list_del_init(&page->lru);
- __free_page(page);
- }
-}
-
static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
- int gmr_id, struct list_head *desc_pages)
+ int gmr_id, dma_addr_t desc_dma)
{
- struct page *page;
-
- if (unlikely(list_empty(desc_pages)))
- return;
-
- page = list_entry(desc_pages->next, struct page, lru);
-
mutex_lock(&dev_priv->hw_mutex);
vmw_write(dev_priv, SVGA_REG_GMR_ID, gmr_id);
wmb();
- vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, page_to_pfn(page));
+ vmw_write(dev_priv, SVGA_REG_GMR_DESCRIPTOR, desc_dma >> PAGE_SHIFT);
mb();
mutex_unlock(&dev_priv->hw_mutex);
}
-/**
- * FIXME: Adjust to the ttm lowmem / highmem storage to minimize
- * the number of used descriptors.
- */
-
-static unsigned long vmw_gmr_count_descriptors(struct page *pages[],
- unsigned long num_pages)
-{
- unsigned long prev_pfn = ~(0UL);
- unsigned long pfn;
- unsigned long descriptors = 0;
-
- while (num_pages--) {
- pfn = page_to_pfn(*pages++);
- if (prev_pfn + 1 != pfn)
- ++descriptors;
- prev_pfn = pfn;
- }
-
- return descriptors;
-}
-
int vmw_gmr_bind(struct vmw_private *dev_priv,
- struct page *pages[],
+ const struct vmw_sg_table *vsgt,
unsigned long num_pages,
int gmr_id)
{
struct list_head desc_pages;
+ dma_addr_t desc_dma = 0;
+ struct device *dev = dev_priv->dev->dev;
+ struct vmw_piter data_iter;
int ret;
+ vmw_piter_start(&data_iter, vsgt, 0);
+
+ if (unlikely(!vmw_piter_next(&data_iter)))
+ return 0;
+
if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
- return vmw_gmr2_bind(dev_priv, pages, num_pages, gmr_id);
+ return vmw_gmr2_bind(dev_priv, &data_iter, num_pages, gmr_id);
if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
return -EINVAL;
- if (vmw_gmr_count_descriptors(pages, num_pages) >
- dev_priv->max_gmr_descriptors)
+ if (vsgt->num_regions > dev_priv->max_gmr_descriptors)
return -EINVAL;
INIT_LIST_HEAD(&desc_pages);
- ret = vmw_gmr_build_descriptors(&desc_pages, pages, num_pages);
+ ret = vmw_gmr_build_descriptors(dev, &desc_pages, &data_iter,
+ num_pages, &desc_dma);
if (unlikely(ret != 0))
return ret;
- vmw_gmr_fire_descriptors(dev_priv, gmr_id, &desc_pages);
- vmw_gmr_free_descriptors(&desc_pages);
+ vmw_gmr_fire_descriptors(dev_priv, gmr_id, desc_dma);
+ vmw_gmr_free_descriptors(dev, desc_dma, &desc_pages);
return 0;
}