Re: [PATCH v5] drm/nouveau: map pages using DMA API

On Thu, Jul 31, 2014 at 06:09:42PM +0900, Alexandre Courbot wrote:

The DMA API is the recommended way to map pages no matter what the underlying bus is. Use the DMA functions for page mapping and remove currently existing wrappers.

Signed-off-by: Alexandre Courbot acourbot@nvidia.com Cc: Daniel Vetter daniel@ffwll.ch

---

Changes since v4:

• Patch against the Nouveau tree instead of the kernel
• Separated this patch from the rest of the series since it can be merged alone
• Replaced all pci_map invokations with dma_map. As Daniel pointed out, using the PCI API is deprecated:

Documentation/DMA-API-HOWTO.txt:

"Note that the DMA API works with any bus independent of the underlying microprocessor architecture. You should use the DMA API rather than the bus-specific DMA API, i.e., use the dma_map_*() interfaces rather than the pci_map_*() interfaces."

• As a result, removed the page mapping wrappers which have become unneeded.

Acked-by: Daniel Vetter daniel.vetter@ffwll.ch

drm/nouveau_bo.c | 22 ++++++++++++++++------ lib/core/os.h | 8 ++++---- nvkm/engine/device/base.c | 25 ------------------------- nvkm/include/core/device.h | 6 ------ nvkm/subdev/fb/nv50.c | 7 +++++-- nvkm/subdev/fb/nvc0.c | 7 +++++-- 6 files changed, 30 insertions(+), 45 deletions(-)

diff --git a/drm/nouveau_bo.c b/drm/nouveau_bo.c index 4db886f9f793..e4f2071c46c3 100644 --- a/drm/nouveau_bo.c +++ b/drm/nouveau_bo.c @@ -1340,6 +1340,7 @@ nouveau_ttm_tt_populate(struct ttm_tt *ttm) struct nouveau_drm *drm; struct nouveau_device *device; struct drm_device *dev;

• struct device *pdev; unsigned i; int r; bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG);

@@ -1358,6 +1359,7 @@ nouveau_ttm_tt_populate(struct ttm_tt *ttm) drm = nouveau_bdev(ttm->bdev); device = nv_device(drm->device); dev = drm->dev;

• pdev = nv_device_base(device);

#if __OS_HAS_AGP if (drm->agp.stat == ENABLED) { @@ -1377,17 +1379,22 @@ nouveau_ttm_tt_populate(struct ttm_tt *ttm) }

for (i = 0; i < ttm->num_pages; i++) {

• ttm_dma->dma_address[i] = nv_device_map_page(device,
  

• 					     ttm->pages[i]);
  

• if (!ttm_dma->dma_address[i]) {
  

• dma_addr_t addr;
  

• addr = dma_map_page(pdev, ttm->pages[i], 0, PAGE_SIZE,
  

• 		    DMA_BIDIRECTIONAL);
  

• if (dma_mapping_error(pdev, addr)) {
  while (--i) {
  

• 		nv_device_unmap_page(device,
  

• 				     ttm_dma->dma_address[i]);
  

• 		dma_unmap_page(pdev, ttm_dma->dma_address[i],
  

• 			       PAGE_SIZE, DMA_BIDIRECTIONAL);
  	ttm_dma->dma_address[i] = 0;
  }
  ttm_pool_unpopulate(ttm);
  return -EFAULT;
  

  }

• ttm_dma->dma_address[i] = addr;
  

  } return 0;

} @@ -1399,6 +1406,7 @@ nouveau_ttm_tt_unpopulate(struct ttm_tt *ttm) struct nouveau_drm *drm; struct nouveau_device *device; struct drm_device *dev;

• struct device *pdev; unsigned i; bool slave = !!(ttm->page_flags & TTM_PAGE_FLAG_SG);

@@ -1408,6 +1416,7 @@ nouveau_ttm_tt_unpopulate(struct ttm_tt *ttm) drm = nouveau_bdev(ttm->bdev); device = nv_device(drm->device); dev = drm->dev;

• pdev = nv_device_base(device);

#if __OS_HAS_AGP if (drm->agp.stat == ENABLED) { @@ -1425,7 +1434,8 @@ nouveau_ttm_tt_unpopulate(struct ttm_tt *ttm)

for (i = 0; i < ttm->num_pages; i++) { if (ttm_dma->dma_address[i]) {

• 	nv_device_unmap_page(device, ttm_dma->dma_address[i]);
  

• 	dma_unmap_page(pdev, ttm_dma->dma_address[i], PAGE_SIZE,
  

• 		       DMA_BIDIRECTIONAL);
  

  } }

diff --git a/lib/core/os.h b/lib/core/os.h index 5f4f04fbff3d..596e083ffb36 100644 --- a/lib/core/os.h +++ b/lib/core/os.h @@ -644,7 +644,7 @@ dma_free_coherent(struct device *dev, size_t sz, void *vaddr, dma_addr_t bus) *****************************************************************************/ #include <pciaccess.h>

-#define PCI_DMA_BIDIRECTIONAL 1 +#define DMA_BIDIRECTIONAL 1

#define PCI_CAP_ID_AGP 0x02

@@ -688,7 +688,7 @@ pci_resource_len(struct pci_dev *pdev, int bar) }

static inline dma_addr_t -pci_map_page(struct pci_dev *pdev, struct page *page, int offset, +dma_map_page(struct device *pdev, struct page *page, int offset, int length, unsigned flags) { return 0; @@ -696,13 +696,13 @@ pci_map_page(struct pci_dev *pdev, struct page *page, int offset,

static inline bool -pci_dma_mapping_error(struct pci_dev *pdev, dma_addr_t addr) +dma_mapping_error(struct device *pdev, dma_addr_t addr) { return true; }

static inline void -pci_unmap_page(struct pci_dev *pdev, dma_addr_t addr, int size, unsigned flags) +dma_unmap_page(struct device *pdev, dma_addr_t addr, int size, unsigned flags) { }

diff --git a/nvkm/engine/device/base.c b/nvkm/engine/device/base.c index 466dda2f7a3a..6c16dabe13b3 100644 --- a/nvkm/engine/device/base.c +++ b/nvkm/engine/device/base.c @@ -487,31 +487,6 @@ nv_device_resource_len(struct nouveau_device *device, unsigned int bar) } }

-dma_addr_t -nv_device_map_page(struct nouveau_device *device, struct page *page) -{

• dma_addr_t ret;
• if (nv_device_is_pci(device)) {

• ret = pci_map_page(device->pdev, page, 0, PAGE_SIZE,
  

• 		   PCI_DMA_BIDIRECTIONAL);
  

• if (pci_dma_mapping_error(device->pdev, ret))
  

• 	ret = 0;
  

• } else {

• ret = page_to_phys(page);
  

• }
• return ret;

-}

-void -nv_device_unmap_page(struct nouveau_device *device, dma_addr_t addr) -{

• if (nv_device_is_pci(device))

• pci_unmap_page(device->pdev, addr, PAGE_SIZE,
  

• 	       PCI_DMA_BIDIRECTIONAL);
  

-}

int nv_device_get_irq(struct nouveau_device *device, bool stall) { diff --git a/nvkm/include/core/device.h b/nvkm/include/core/device.h index 9ce2ee9aa32e..03c039dcc61f 100644 --- a/nvkm/include/core/device.h +++ b/nvkm/include/core/device.h @@ -174,12 +174,6 @@ nv_device_resource_start(struct nouveau_device *device, unsigned int bar); resource_size_t nv_device_resource_len(struct nouveau_device *device, unsigned int bar);

-dma_addr_t -nv_device_map_page(struct nouveau_device *device, struct page *page);

-void -nv_device_unmap_page(struct nouveau_device *device, dma_addr_t addr);

int nv_device_get_irq(struct nouveau_device *device, bool stall);

diff --git a/nvkm/subdev/fb/nv50.c b/nvkm/subdev/fb/nv50.c index 1fc55c1e91a1..7d88e17fa927 100644 --- a/nvkm/subdev/fb/nv50.c +++ b/nvkm/subdev/fb/nv50.c @@ -250,7 +250,9 @@ nv50_fb_ctor(struct nouveau_object *parent, struct nouveau_object *engine,

priv->r100c08_page = alloc_page(GFP_KERNEL | __GFP_ZERO); if (priv->r100c08_page) {

• priv->r100c08 = nv_device_map_page(device, priv->r100c08_page);
  

• priv->r100c08 = dma_map_page(nv_device_base(device),
  

• 			     priv->r100c08_page, 0, PAGE_SIZE,
  

• 			     DMA_BIDIRECTIONAL);
  

  if (!priv->r100c08) nv_warn(priv, "failed 0x100c08 page map\n"); } else {

@@ -268,7 +270,8 @@ nv50_fb_dtor(struct nouveau_object *object) struct nv50_fb_priv *priv = (void *)object;

if (priv->r100c08_page) {

• nv_device_unmap_page(device, priv->r100c08);
  

• dma_unmap_page(nv_device_base(device), priv->r100c08, PAGE_SIZE,
  

• 	       DMA_BIDIRECTIONAL);
  

  __free_page(priv->r100c08_page); }

diff --git a/nvkm/subdev/fb/nvc0.c b/nvkm/subdev/fb/nvc0.c index 0670ae33ee45..9f5f3ac8d4c6 100644 --- a/nvkm/subdev/fb/nvc0.c +++ b/nvkm/subdev/fb/nvc0.c @@ -70,7 +70,8 @@ nvc0_fb_dtor(struct nouveau_object *object) struct nvc0_fb_priv *priv = (void *)object;

if (priv->r100c10_page) {

• nv_device_unmap_page(device, priv->r100c10);
  

• dma_unmap_page(nv_device_base(device), priv->r100c10, PAGE_SIZE,
  

• 	       DMA_BIDIRECTIONAL);
  

  __free_page(priv->r100c10_page); }

@@ -93,7 +94,9 @@ nvc0_fb_ctor(struct nouveau_object *parent, struct nouveau_object *engine,

priv->r100c10_page = alloc_page(GFP_KERNEL | __GFP_ZERO); if (priv->r100c10_page) {

• priv->r100c10 = nv_device_map_page(device, priv->r100c10_page);
  

• priv->r100c10 = dma_map_page(nv_device_base(device),
  

• 			     priv->r100c10_page, 0, PAGE_SIZE,
  

• 			     DMA_BIDIRECTIONAL);
  

  if (!priv->r100c10) return -EFAULT; }

-- 2.0.3