drm/vmwgfx: Fix the driver for large dma addresses

With dma compliance / IOMMU support added to the driver in kernel 3.13,
the dma addresses can exceed 44 bits, which is what we support in
32-bit mode and with GMR1.
So in 32-bit mode and optionally in 64-bit mode, restrict the dma
addresses to 44 bits, and strip the old GMR1 code.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index c7a5496..6c792f7 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -189,6 +189,7 @@ static int enable_fbdev = IS_ENABLED(CONFIG_DRM_VMWGFX_FBCON);
 static int vmw_force_iommu;
 static int vmw_restrict_iommu;
 static int vmw_force_coherent;
+static int vmw_restrict_dma_mask;
 
 static int vmw_probe(struct pci_dev *, const struct pci_device_id *);
 static void vmw_master_init(struct vmw_master *);
@@ -203,6 +204,8 @@ MODULE_PARM_DESC(restrict_iommu, "Try to limit IOMMU usage for TTM pages");
 module_param_named(restrict_iommu, vmw_restrict_iommu, int, 0600);
 MODULE_PARM_DESC(force_coherent, "Force coherent TTM pages");
 module_param_named(force_coherent, vmw_force_coherent, int, 0600);
+MODULE_PARM_DESC(restrict_dma_mask, "Restrict DMA mask to 44 bits with IOMMU");
+module_param_named(restrict_dma_mask, vmw_restrict_dma_mask, int, 0600);
 
 
 static void vmw_print_capabilities(uint32_t capabilities)
@@ -510,6 +513,33 @@ out_fixup:
        return 0;
 }
 
+/**
+ * vmw_dma_masks - set required page- and dma masks
+ *
+ * @dev: Pointer to struct drm-device
+ *
+ * With 32-bit we can only handle 32 bit PFNs. Optionally set that
+ * restriction also for 64-bit systems.
+ */
+#ifdef CONFIG_INTEL_IOMMU
+static int vmw_dma_masks(struct vmw_private *dev_priv)
+{
+       struct drm_device *dev = dev_priv->dev;
+
+       if (intel_iommu_enabled &&
+           (sizeof(unsigned long) == 4 || vmw_restrict_dma_mask)) {
+               DRM_INFO("Restricting DMA addresses to 44 bits.\n");
+               return dma_set_mask(dev->dev, DMA_BIT_MASK(44));
+       }
+       return 0;
+}
+#else
+static int vmw_dma_masks(struct vmw_private *dev_priv)
+{
+       return 0;
+}
+#endif
+
 static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
 {
        struct vmw_private *dev_priv;
@@ -578,14 +608,9 @@ static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
 
        vmw_get_initial_size(dev_priv);
 
-       if (dev_priv->capabilities & SVGA_CAP_GMR) {
-               dev_priv->max_gmr_descriptors =
-                       vmw_read(dev_priv,
-                                SVGA_REG_GMR_MAX_DESCRIPTOR_LENGTH);
+       if (dev_priv->capabilities & SVGA_CAP_GMR2) {
                dev_priv->max_gmr_ids =
                        vmw_read(dev_priv, SVGA_REG_GMR_MAX_IDS);
-       }
-       if (dev_priv->capabilities & SVGA_CAP_GMR2) {
                dev_priv->max_gmr_pages =
                        vmw_read(dev_priv, SVGA_REG_GMRS_MAX_PAGES);
                dev_priv->memory_size =
@@ -599,17 +624,17 @@ static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
                dev_priv->memory_size = 512*1024*1024;
        }
 
+       ret = vmw_dma_masks(dev_priv);
+       if (unlikely(ret != 0))
+               goto out_err0;
+
        mutex_unlock(&dev_priv->hw_mutex);
 
        vmw_print_capabilities(dev_priv->capabilities);
 
-       if (dev_priv->capabilities & SVGA_CAP_GMR) {
+       if (dev_priv->capabilities & SVGA_CAP_GMR2) {
                DRM_INFO("Max GMR ids is %u\n",
                         (unsigned)dev_priv->max_gmr_ids);
-               DRM_INFO("Max GMR descriptors is %u\n",
-                        (unsigned)dev_priv->max_gmr_descriptors);
-       }
-       if (dev_priv->capabilities & SVGA_CAP_GMR2) {
                DRM_INFO("Max number of GMR pages is %u\n",
                         (unsigned)dev_priv->max_gmr_pages);
                DRM_INFO("Max dedicated hypervisor surface memory is %u kiB\n",

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index 036629d..ba49c1d 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -290,7 +290,6 @@ struct vmw_private {
        __le32 __iomem *mmio_virt;
        int mmio_mtrr;
        uint32_t capabilities;
-       uint32_t max_gmr_descriptors;
        uint32_t max_gmr_ids;
        uint32_t max_gmr_pages;
        uint32_t memory_size;

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
index 6ef0b03..61d8d80 100644 (file)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c
@@ -125,181 +125,27 @@ static void vmw_gmr2_unbind(struct vmw_private *dev_priv,
 }
 
 
-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 = (dma_addr_t)
-                       le32_to_cpu(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 device *dev,
-                                    struct list_head *desc_pages,
-                                    struct vmw_piter *iter,
-                                    unsigned long num_pages,
-                                    dma_addr_t *first_dma)
-{
-       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;
-
-       while (likely(num_pages != 0)) {
-               page = alloc_page(__GFP_HIGHMEM);
-               if (unlikely(page == NULL)) {
-                       ret = -ENOMEM;
-                       goto out_err;
-               }
-
-               list_add_tail(&page->lru, desc_pages);
-               page_virtual = kmap_atomic(page);
-               desc_virtual = page_virtual - 1;
-               prev_pfn = ~(0UL);
-
-               while (likely(num_pages != 0)) {
-                       pfn = vmw_piter_dma_addr(iter) >> PAGE_SHIFT;
-
-                       if (pfn != prev_pfn + 1) {
-
-                               if (desc_virtual - page_virtual ==
-                                   desc_per_page - 1)
-                                       break;
-
-                               (++desc_virtual)->ppn = cpu_to_le32(pfn);
-                               desc_virtual->num_pages = cpu_to_le32(1);
-                       } else {
-                               uint32_t tmp =
-                                   le32_to_cpu(desc_virtual->num_pages);
-                               desc_virtual->num_pages = cpu_to_le32(tmp + 1);
-                       }
-                       prev_pfn = pfn;
-                       --num_pages;
-                       vmw_piter_next(iter);
-               }
-
-               (++desc_virtual)->ppn = DMA_PAGE_INVALID;
-               desc_virtual->num_pages = cpu_to_le32(0);
-               kunmap_atomic(page_virtual);
-       }
-
-       desc_dma = 0;
-       list_for_each_entry_reverse(page, desc_pages, lru) {
-               page_virtual = kmap_atomic(page);
-               page_virtual[desc_per_page].ppn = cpu_to_le32
-                       (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:
-       vmw_gmr_free_descriptors(dev, DMA_ADDR_INVALID, desc_pages);
-       return ret;
-}
-
-static void vmw_gmr_fire_descriptors(struct vmw_private *dev_priv,
-                                    int gmr_id, dma_addr_t desc_dma)
-{
-       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, desc_dma >> PAGE_SHIFT);
-       mb();
-
-       mutex_unlock(&dev_priv->hw_mutex);
-
-}
-
 int vmw_gmr_bind(struct vmw_private *dev_priv,
                 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, &data_iter, num_pages, gmr_id);
-
-       if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR)))
-               return -EINVAL;
-
-       if (vsgt->num_regions > dev_priv->max_gmr_descriptors)
+       if (unlikely(!(dev_priv->capabilities & SVGA_CAP_GMR2)))
                return -EINVAL;
 
-       INIT_LIST_HEAD(&desc_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_dma);
-       vmw_gmr_free_descriptors(dev, desc_dma, &desc_pages);
-
-       return 0;
+       return vmw_gmr2_bind(dev_priv, &data_iter, num_pages, gmr_id);
 }
 
 
 void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id)
 {
-       if (likely(dev_priv->capabilities & SVGA_CAP_GMR2)) {
+       if (likely(dev_priv->capabilities & SVGA_CAP_GMR2))
                vmw_gmr2_unbind(dev_priv, gmr_id);
-               return;
-       }
-
-       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, 0);
-       mb();
-       mutex_unlock(&dev_priv->hw_mutex);
 }