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_buffer.c b/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
index 96dc84d..7776e6f 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_buffer.c
@@ -141,37 +141,374 @@
};
struct vmw_ttm_tt {
- struct ttm_tt ttm;
+ struct ttm_dma_tt dma_ttm;
struct vmw_private *dev_priv;
int gmr_id;
+ struct sg_table sgt;
+ struct vmw_sg_table vsgt;
+ uint64_t sg_alloc_size;
+ bool mapped;
};
+/**
+ * Helper functions to advance a struct vmw_piter iterator.
+ *
+ * @viter: Pointer to the iterator.
+ *
+ * These functions return false if past the end of the list,
+ * true otherwise. Functions are selected depending on the current
+ * DMA mapping mode.
+ */
+static bool __vmw_piter_non_sg_next(struct vmw_piter *viter)
+{
+ return ++(viter->i) < viter->num_pages;
+}
+
+static bool __vmw_piter_sg_next(struct vmw_piter *viter)
+{
+ return __sg_page_iter_next(&viter->iter);
+}
+
+
+/**
+ * Helper functions to return a pointer to the current page.
+ *
+ * @viter: Pointer to the iterator
+ *
+ * These functions return a pointer to the page currently
+ * pointed to by @viter. Functions are selected depending on the
+ * current mapping mode.
+ */
+static struct page *__vmw_piter_non_sg_page(struct vmw_piter *viter)
+{
+ return viter->pages[viter->i];
+}
+
+static struct page *__vmw_piter_sg_page(struct vmw_piter *viter)
+{
+ return sg_page_iter_page(&viter->iter);
+}
+
+
+/**
+ * Helper functions to return the DMA address of the current page.
+ *
+ * @viter: Pointer to the iterator
+ *
+ * These functions return the DMA address of the page currently
+ * pointed to by @viter. Functions are selected depending on the
+ * current mapping mode.
+ */
+static dma_addr_t __vmw_piter_phys_addr(struct vmw_piter *viter)
+{
+ return page_to_phys(viter->pages[viter->i]);
+}
+
+static dma_addr_t __vmw_piter_dma_addr(struct vmw_piter *viter)
+{
+ return viter->addrs[viter->i];
+}
+
+static dma_addr_t __vmw_piter_sg_addr(struct vmw_piter *viter)
+{
+ return sg_page_iter_dma_address(&viter->iter);
+}
+
+
+/**
+ * vmw_piter_start - Initialize a struct vmw_piter.
+ *
+ * @viter: Pointer to the iterator to initialize
+ * @vsgt: Pointer to a struct vmw_sg_table to initialize from
+ *
+ * Note that we're following the convention of __sg_page_iter_start, so that
+ * the iterator doesn't point to a valid page after initialization; it has
+ * to be advanced one step first.
+ */
+void vmw_piter_start(struct vmw_piter *viter, const struct vmw_sg_table *vsgt,
+ unsigned long p_offset)
+{
+ viter->i = p_offset - 1;
+ viter->num_pages = vsgt->num_pages;
+ switch (vsgt->mode) {
+ case vmw_dma_phys:
+ viter->next = &__vmw_piter_non_sg_next;
+ viter->dma_address = &__vmw_piter_phys_addr;
+ viter->page = &__vmw_piter_non_sg_page;
+ viter->pages = vsgt->pages;
+ break;
+ case vmw_dma_alloc_coherent:
+ viter->next = &__vmw_piter_non_sg_next;
+ viter->dma_address = &__vmw_piter_dma_addr;
+ viter->page = &__vmw_piter_non_sg_page;
+ viter->addrs = vsgt->addrs;
+ break;
+ case vmw_dma_map_populate:
+ case vmw_dma_map_bind:
+ viter->next = &__vmw_piter_sg_next;
+ viter->dma_address = &__vmw_piter_sg_addr;
+ viter->page = &__vmw_piter_sg_page;
+ __sg_page_iter_start(&viter->iter, vsgt->sgt->sgl,
+ vsgt->sgt->orig_nents, p_offset);
+ break;
+ default:
+ BUG();
+ }
+}
+
+/**
+ * vmw_ttm_unmap_from_dma - unmap device addresses previsouly mapped for
+ * TTM pages
+ *
+ * @vmw_tt: Pointer to a struct vmw_ttm_backend
+ *
+ * Used to free dma mappings previously mapped by vmw_ttm_map_for_dma.
+ */
+static void vmw_ttm_unmap_from_dma(struct vmw_ttm_tt *vmw_tt)
+{
+ struct device *dev = vmw_tt->dev_priv->dev->dev;
+
+ dma_unmap_sg(dev, vmw_tt->sgt.sgl, vmw_tt->sgt.nents,
+ DMA_BIDIRECTIONAL);
+ vmw_tt->sgt.nents = vmw_tt->sgt.orig_nents;
+}
+
+/**
+ * vmw_ttm_map_for_dma - map TTM pages to get device addresses
+ *
+ * @vmw_tt: Pointer to a struct vmw_ttm_backend
+ *
+ * This function is used to get device addresses from the kernel DMA layer.
+ * However, it's violating the DMA API in that when this operation has been
+ * performed, it's illegal for the CPU to write to the pages without first
+ * unmapping the DMA mappings, or calling dma_sync_sg_for_cpu(). It is
+ * therefore only legal to call this function if we know that the function
+ * dma_sync_sg_for_cpu() is a NOP, and dma_sync_sg_for_device() is at most
+ * a CPU write buffer flush.
+ */
+static int vmw_ttm_map_for_dma(struct vmw_ttm_tt *vmw_tt)
+{
+ struct device *dev = vmw_tt->dev_priv->dev->dev;
+ int ret;
+
+ ret = dma_map_sg(dev, vmw_tt->sgt.sgl, vmw_tt->sgt.orig_nents,
+ DMA_BIDIRECTIONAL);
+ if (unlikely(ret == 0))
+ return -ENOMEM;
+
+ vmw_tt->sgt.nents = ret;
+
+ return 0;
+}
+
+/**
+ * vmw_ttm_map_dma - Make sure TTM pages are visible to the device
+ *
+ * @vmw_tt: Pointer to a struct vmw_ttm_tt
+ *
+ * Select the correct function for and make sure the TTM pages are
+ * visible to the device. Allocate storage for the device mappings.
+ * If a mapping has already been performed, indicated by the storage
+ * pointer being non NULL, the function returns success.
+ */
+static int vmw_ttm_map_dma(struct vmw_ttm_tt *vmw_tt)
+{
+ struct vmw_private *dev_priv = vmw_tt->dev_priv;
+ struct ttm_mem_global *glob = vmw_mem_glob(dev_priv);
+ struct vmw_sg_table *vsgt = &vmw_tt->vsgt;
+ struct vmw_piter iter;
+ dma_addr_t old;
+ int ret = 0;
+ static size_t sgl_size;
+ static size_t sgt_size;
+
+ if (vmw_tt->mapped)
+ return 0;
+
+ vsgt->mode = dev_priv->map_mode;
+ vsgt->pages = vmw_tt->dma_ttm.ttm.pages;
+ vsgt->num_pages = vmw_tt->dma_ttm.ttm.num_pages;
+ vsgt->addrs = vmw_tt->dma_ttm.dma_address;
+ vsgt->sgt = &vmw_tt->sgt;
+
+ switch (dev_priv->map_mode) {
+ case vmw_dma_map_bind:
+ case vmw_dma_map_populate:
+ if (unlikely(!sgl_size)) {
+ sgl_size = ttm_round_pot(sizeof(struct scatterlist));
+ sgt_size = ttm_round_pot(sizeof(struct sg_table));
+ }
+ vmw_tt->sg_alloc_size = sgt_size + sgl_size * vsgt->num_pages;
+ ret = ttm_mem_global_alloc(glob, vmw_tt->sg_alloc_size, false,
+ true);
+ if (unlikely(ret != 0))
+ return ret;
+
+ ret = sg_alloc_table_from_pages(&vmw_tt->sgt, vsgt->pages,
+ vsgt->num_pages, 0,
+ (unsigned long)
+ vsgt->num_pages << PAGE_SHIFT,
+ GFP_KERNEL);
+ if (unlikely(ret != 0))
+ goto out_sg_alloc_fail;
+
+ if (vsgt->num_pages > vmw_tt->sgt.nents) {
+ uint64_t over_alloc =
+ sgl_size * (vsgt->num_pages -
+ vmw_tt->sgt.nents);
+
+ ttm_mem_global_free(glob, over_alloc);
+ vmw_tt->sg_alloc_size -= over_alloc;
+ }
+
+ ret = vmw_ttm_map_for_dma(vmw_tt);
+ if (unlikely(ret != 0))
+ goto out_map_fail;
+
+ break;
+ default:
+ break;
+ }
+
+ old = ~((dma_addr_t) 0);
+ vmw_tt->vsgt.num_regions = 0;
+ for (vmw_piter_start(&iter, vsgt, 0); vmw_piter_next(&iter);) {
+ dma_addr_t cur = vmw_piter_dma_addr(&iter);
+
+ if (cur != old + PAGE_SIZE)
+ vmw_tt->vsgt.num_regions++;
+ old = cur;
+ }
+
+ vmw_tt->mapped = true;
+ return 0;
+
+out_map_fail:
+ sg_free_table(vmw_tt->vsgt.sgt);
+ vmw_tt->vsgt.sgt = NULL;
+out_sg_alloc_fail:
+ ttm_mem_global_free(glob, vmw_tt->sg_alloc_size);
+ return ret;
+}
+
+/**
+ * vmw_ttm_unmap_dma - Tear down any TTM page device mappings
+ *
+ * @vmw_tt: Pointer to a struct vmw_ttm_tt
+ *
+ * Tear down any previously set up device DMA mappings and free
+ * any storage space allocated for them. If there are no mappings set up,
+ * this function is a NOP.
+ */
+static void vmw_ttm_unmap_dma(struct vmw_ttm_tt *vmw_tt)
+{
+ struct vmw_private *dev_priv = vmw_tt->dev_priv;
+
+ if (!vmw_tt->vsgt.sgt)
+ return;
+
+ switch (dev_priv->map_mode) {
+ case vmw_dma_map_bind:
+ case vmw_dma_map_populate:
+ vmw_ttm_unmap_from_dma(vmw_tt);
+ sg_free_table(vmw_tt->vsgt.sgt);
+ vmw_tt->vsgt.sgt = NULL;
+ ttm_mem_global_free(vmw_mem_glob(dev_priv),
+ vmw_tt->sg_alloc_size);
+ break;
+ default:
+ break;
+ }
+ vmw_tt->mapped = false;
+}
+
static int vmw_ttm_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
{
- struct vmw_ttm_tt *vmw_be = container_of(ttm, struct vmw_ttm_tt, ttm);
+ struct vmw_ttm_tt *vmw_be =
+ container_of(ttm, struct vmw_ttm_tt, dma_ttm.ttm);
+ int ret;
+
+ ret = vmw_ttm_map_dma(vmw_be);
+ if (unlikely(ret != 0))
+ return ret;
vmw_be->gmr_id = bo_mem->start;
- return vmw_gmr_bind(vmw_be->dev_priv, ttm->pages,
+ return vmw_gmr_bind(vmw_be->dev_priv, &vmw_be->vsgt,
ttm->num_pages, vmw_be->gmr_id);
}
static int vmw_ttm_unbind(struct ttm_tt *ttm)
{
- struct vmw_ttm_tt *vmw_be = container_of(ttm, struct vmw_ttm_tt, ttm);
+ struct vmw_ttm_tt *vmw_be =
+ container_of(ttm, struct vmw_ttm_tt, dma_ttm.ttm);
vmw_gmr_unbind(vmw_be->dev_priv, vmw_be->gmr_id);
+
+ if (vmw_be->dev_priv->map_mode == vmw_dma_map_bind)
+ vmw_ttm_unmap_dma(vmw_be);
+
return 0;
}
static void vmw_ttm_destroy(struct ttm_tt *ttm)
{
- struct vmw_ttm_tt *vmw_be = container_of(ttm, struct vmw_ttm_tt, ttm);
+ struct vmw_ttm_tt *vmw_be =
+ container_of(ttm, struct vmw_ttm_tt, dma_ttm.ttm);
- ttm_tt_fini(ttm);
+ vmw_ttm_unmap_dma(vmw_be);
+ if (vmw_be->dev_priv->map_mode == vmw_dma_alloc_coherent)
+ ttm_dma_tt_fini(&vmw_be->dma_ttm);
+ else
+ ttm_tt_fini(ttm);
kfree(vmw_be);
}
+static int vmw_ttm_populate(struct ttm_tt *ttm)
+{
+ struct vmw_ttm_tt *vmw_tt =
+ container_of(ttm, struct vmw_ttm_tt, dma_ttm.ttm);
+ struct vmw_private *dev_priv = vmw_tt->dev_priv;
+ struct ttm_mem_global *glob = vmw_mem_glob(dev_priv);
+ int ret;
+
+ if (ttm->state != tt_unpopulated)
+ return 0;
+
+ if (dev_priv->map_mode == vmw_dma_alloc_coherent) {
+ size_t size =
+ ttm_round_pot(ttm->num_pages * sizeof(dma_addr_t));
+ ret = ttm_mem_global_alloc(glob, size, false, true);
+ if (unlikely(ret != 0))
+ return ret;
+
+ ret = ttm_dma_populate(&vmw_tt->dma_ttm, dev_priv->dev->dev);
+ if (unlikely(ret != 0))
+ ttm_mem_global_free(glob, size);
+ } else
+ ret = ttm_pool_populate(ttm);
+
+ return ret;
+}
+
+static void vmw_ttm_unpopulate(struct ttm_tt *ttm)
+{
+ struct vmw_ttm_tt *vmw_tt = container_of(ttm, struct vmw_ttm_tt,
+ dma_ttm.ttm);
+ struct vmw_private *dev_priv = vmw_tt->dev_priv;
+ struct ttm_mem_global *glob = vmw_mem_glob(dev_priv);
+
+ vmw_ttm_unmap_dma(vmw_tt);
+ if (dev_priv->map_mode == vmw_dma_alloc_coherent) {
+ size_t size =
+ ttm_round_pot(ttm->num_pages * sizeof(dma_addr_t));
+
+ ttm_dma_unpopulate(&vmw_tt->dma_ttm, dev_priv->dev->dev);
+ ttm_mem_global_free(glob, size);
+ } else
+ ttm_pool_unpopulate(ttm);
+}
+
static struct ttm_backend_func vmw_ttm_func = {
.bind = vmw_ttm_bind,
.unbind = vmw_ttm_unbind,
@@ -183,20 +520,28 @@
struct page *dummy_read_page)
{
struct vmw_ttm_tt *vmw_be;
+ int ret;
- vmw_be = kmalloc(sizeof(*vmw_be), GFP_KERNEL);
+ vmw_be = kzalloc(sizeof(*vmw_be), GFP_KERNEL);
if (!vmw_be)
return NULL;
- vmw_be->ttm.func = &vmw_ttm_func;
+ vmw_be->dma_ttm.ttm.func = &vmw_ttm_func;
vmw_be->dev_priv = container_of(bdev, struct vmw_private, bdev);
- if (ttm_tt_init(&vmw_be->ttm, bdev, size, page_flags, dummy_read_page)) {
- kfree(vmw_be);
- return NULL;
- }
+ if (vmw_be->dev_priv->map_mode == vmw_dma_alloc_coherent)
+ ret = ttm_dma_tt_init(&vmw_be->dma_ttm, bdev, size, page_flags,
+ dummy_read_page);
+ else
+ ret = ttm_tt_init(&vmw_be->dma_ttm.ttm, bdev, size, page_flags,
+ dummy_read_page);
+ if (unlikely(ret != 0))
+ goto out_no_init;
- return &vmw_be->ttm;
+ return &vmw_be->dma_ttm.ttm;
+out_no_init:
+ kfree(vmw_be);
+ return NULL;
}
int vmw_invalidate_caches(struct ttm_bo_device *bdev, uint32_t flags)
@@ -332,8 +677,8 @@
struct ttm_bo_driver vmw_bo_driver = {
.ttm_tt_create = &vmw_ttm_tt_create,
- .ttm_tt_populate = &ttm_pool_populate,
- .ttm_tt_unpopulate = &ttm_pool_unpopulate,
+ .ttm_tt_populate = &vmw_ttm_populate,
+ .ttm_tt_unpopulate = &vmw_ttm_unpopulate,
.invalidate_caches = vmw_invalidate_caches,
.init_mem_type = vmw_init_mem_type,
.evict_flags = vmw_evict_flags,
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index 1a90f0a..0b5c781 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -32,6 +32,7 @@
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_object.h>
#include <drm/ttm/ttm_module.h>
+#include <linux/dma_remapping.h>
#define VMWGFX_DRIVER_NAME "vmwgfx"
#define VMWGFX_DRIVER_DESC "Linux drm driver for VMware graphics devices"
@@ -185,6 +186,9 @@
MODULE_DEVICE_TABLE(pci, vmw_pci_id_list);
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_probe(struct pci_dev *, const struct pci_device_id *);
static void vmw_master_init(struct vmw_master *);
@@ -193,6 +197,13 @@
MODULE_PARM_DESC(enable_fbdev, "Enable vmwgfx fbdev");
module_param_named(enable_fbdev, enable_fbdev, int, 0600);
+MODULE_PARM_DESC(force_dma_api, "Force using the DMA API for TTM pages");
+module_param_named(force_dma_api, vmw_force_iommu, int, 0600);
+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);
+
static void vmw_print_capabilities(uint32_t capabilities)
{
@@ -427,12 +438,78 @@
dev_priv->initial_height = height;
}
+/**
+ * vmw_dma_select_mode - Determine how DMA mappings should be set up for this
+ * system.
+ *
+ * @dev_priv: Pointer to a struct vmw_private
+ *
+ * This functions tries to determine the IOMMU setup and what actions
+ * need to be taken by the driver to make system pages visible to the
+ * device.
+ * If this function decides that DMA is not possible, it returns -EINVAL.
+ * The driver may then try to disable features of the device that require
+ * DMA.
+ */
+static int vmw_dma_select_mode(struct vmw_private *dev_priv)
+{
+ const struct dma_map_ops *dma_ops = get_dma_ops(dev_priv->dev->dev);
+ static const char *names[vmw_dma_map_max] = {
+ [vmw_dma_phys] = "Using physical TTM page addresses.",
+ [vmw_dma_alloc_coherent] = "Using coherent TTM pages.",
+ [vmw_dma_map_populate] = "Keeping DMA mappings.",
+ [vmw_dma_map_bind] = "Giving up DMA mappings early."};
+
+#ifdef CONFIG_INTEL_IOMMU
+ if (intel_iommu_enabled) {
+ dev_priv->map_mode = vmw_dma_map_populate;
+ goto out_fixup;
+ }
+#endif
+
+ if (!(vmw_force_iommu || vmw_force_coherent)) {
+ dev_priv->map_mode = vmw_dma_phys;
+ DRM_INFO("DMA map mode: %s\n", names[dev_priv->map_mode]);
+ return 0;
+ }
+
+ dev_priv->map_mode = vmw_dma_map_populate;
+
+ if (dma_ops->sync_single_for_cpu)
+ dev_priv->map_mode = vmw_dma_alloc_coherent;
+#ifdef CONFIG_SWIOTLB
+ if (swiotlb_nr_tbl() == 0)
+ dev_priv->map_mode = vmw_dma_map_populate;
+#endif
+
+out_fixup:
+ if (dev_priv->map_mode == vmw_dma_map_populate &&
+ vmw_restrict_iommu)
+ dev_priv->map_mode = vmw_dma_map_bind;
+
+ if (vmw_force_coherent)
+ dev_priv->map_mode = vmw_dma_alloc_coherent;
+
+#if !defined(CONFIG_SWIOTLB) && !defined(CONFIG_INTEL_IOMMU)
+ /*
+ * No coherent page pool
+ */
+ if (dev_priv->map_mode == vmw_dma_alloc_coherent)
+ return -EINVAL;
+#endif
+
+ DRM_INFO("DMA map mode: %s\n", names[dev_priv->map_mode]);
+
+ return 0;
+}
+
static int vmw_driver_load(struct drm_device *dev, unsigned long chipset)
{
struct vmw_private *dev_priv;
int ret;
uint32_t svga_id;
enum vmw_res_type i;
+ bool refuse_dma = false;
dev_priv = kzalloc(sizeof(*dev_priv), GFP_KERNEL);
if (unlikely(dev_priv == NULL)) {
@@ -481,6 +558,11 @@
}
dev_priv->capabilities = vmw_read(dev_priv, SVGA_REG_CAPABILITIES);
+ ret = vmw_dma_select_mode(dev_priv);
+ if (unlikely(ret != 0)) {
+ DRM_INFO("Restricting capabilities due to IOMMU setup.\n");
+ refuse_dma = true;
+ }
dev_priv->vram_size = vmw_read(dev_priv, SVGA_REG_VRAM_SIZE);
dev_priv->mmio_size = vmw_read(dev_priv, SVGA_REG_MEM_SIZE);
@@ -558,8 +640,9 @@
}
dev_priv->has_gmr = true;
- if (ttm_bo_init_mm(&dev_priv->bdev, VMW_PL_GMR,
- dev_priv->max_gmr_ids) != 0) {
+ if (((dev_priv->capabilities & (SVGA_CAP_GMR | SVGA_CAP_GMR2)) == 0) ||
+ refuse_dma || ttm_bo_init_mm(&dev_priv->bdev, VMW_PL_GMR,
+ dev_priv->max_gmr_ids) != 0) {
DRM_INFO("No GMR memory available. "
"Graphics memory resources are very limited.\n");
dev_priv->has_gmr = false;
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index 150ec64..e401d5d 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -177,6 +177,58 @@
struct vmw_resource_val_node *node;
};
+/**
+ * enum vmw_dma_map_mode - indicate how to perform TTM page dma mappings.
+ */
+enum vmw_dma_map_mode {
+ vmw_dma_phys, /* Use physical page addresses */
+ vmw_dma_alloc_coherent, /* Use TTM coherent pages */
+ vmw_dma_map_populate, /* Unmap from DMA just after unpopulate */
+ vmw_dma_map_bind, /* Unmap from DMA just before unbind */
+ vmw_dma_map_max
+};
+
+/**
+ * struct vmw_sg_table - Scatter/gather table for binding, with additional
+ * device-specific information.
+ *
+ * @sgt: Pointer to a struct sg_table with binding information
+ * @num_regions: Number of regions with device-address contigous pages
+ */
+struct vmw_sg_table {
+ enum vmw_dma_map_mode mode;
+ struct page **pages;
+ const dma_addr_t *addrs;
+ struct sg_table *sgt;
+ unsigned long num_regions;
+ unsigned long num_pages;
+};
+
+/**
+ * struct vmw_piter - Page iterator that iterates over a list of pages
+ * and DMA addresses that could be either a scatter-gather list or
+ * arrays
+ *
+ * @pages: Array of page pointers to the pages.
+ * @addrs: DMA addresses to the pages if coherent pages are used.
+ * @iter: Scatter-gather page iterator. Current position in SG list.
+ * @i: Current position in arrays.
+ * @num_pages: Number of pages total.
+ * @next: Function to advance the iterator. Returns false if past the list
+ * of pages, true otherwise.
+ * @dma_address: Function to return the DMA address of the current page.
+ */
+struct vmw_piter {
+ struct page **pages;
+ const dma_addr_t *addrs;
+ struct sg_page_iter iter;
+ unsigned long i;
+ unsigned long num_pages;
+ bool (*next)(struct vmw_piter *);
+ dma_addr_t (*dma_address)(struct vmw_piter *);
+ struct page *(*page)(struct vmw_piter *);
+};
+
struct vmw_sw_context{
struct drm_open_hash res_ht;
bool res_ht_initialized;
@@ -358,6 +410,11 @@
struct list_head res_lru[vmw_res_max];
uint32_t used_memory_size;
+
+ /*
+ * DMA mapping stuff.
+ */
+ enum vmw_dma_map_mode map_mode;
};
static inline struct vmw_surface *vmw_res_to_srf(struct vmw_resource *res)
@@ -405,7 +462,7 @@
*/
extern 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);
extern void vmw_gmr_unbind(struct vmw_private *dev_priv, int gmr_id);
@@ -568,6 +625,45 @@
extern struct ttm_placement vmw_srf_placement;
extern struct ttm_bo_driver vmw_bo_driver;
extern int vmw_dma_quiescent(struct drm_device *dev);
+extern void vmw_piter_start(struct vmw_piter *viter,
+ const struct vmw_sg_table *vsgt,
+ unsigned long p_offs);
+
+/**
+ * vmw_piter_next - Advance the iterator one page.
+ *
+ * @viter: Pointer to the iterator to advance.
+ *
+ * Returns false if past the list of pages, true otherwise.
+ */
+static inline bool vmw_piter_next(struct vmw_piter *viter)
+{
+ return viter->next(viter);
+}
+
+/**
+ * vmw_piter_dma_addr - Return the DMA address of the current page.
+ *
+ * @viter: Pointer to the iterator
+ *
+ * Returns the DMA address of the page pointed to by @viter.
+ */
+static inline dma_addr_t vmw_piter_dma_addr(struct vmw_piter *viter)
+{
+ return viter->dma_address(viter);
+}
+
+/**
+ * vmw_piter_page - Return a pointer to the current page.
+ *
+ * @viter: Pointer to the iterator
+ *
+ * Returns the DMA address of the page pointed to by @viter.
+ */
+static inline struct page *vmw_piter_page(struct vmw_piter *viter)
+{
+ return viter->page(viter);
+}
/**
* Command submission - vmwgfx_execbuf.c
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;
}