[PATCH 3.13 102/120] drm/vmwgfx: Fix the driver for large dma addresses

From: Greg Kroah-Hartman
Date: Tue Feb 11 2014 - 15:41:52 EST


3.13-stable review patch. If anyone has any objections, please let me know.

------------------

From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>

commit 0d00c488f3de59d19784d5ce774528acaa194525 upstream.

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@xxxxxxxxxx>
Reviewed-by: Jakob Bornecrantz <jakob@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/vmwgfx/vmwgfx_drv.c | 47 ++++++++--
drivers/gpu/drm/vmwgfx/vmwgfx_drv.h | 1
drivers/gpu/drm/vmwgfx/vmwgfx_gmr.c | 160 ------------------------------------
3 files changed, 39 insertions(+), 169 deletions(-)

--- 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(CON
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
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_de

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_de
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",
--- 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;
--- 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_p
}


-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);
}


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