On Fri, Sep 05, 2025 at 06:21:44PM +0200, Marek Szyprowski wrote:

On 02.09.2025 16:48, Leon Romanovsky wrote:

quoted

From: Leon Romanovsky <leonro@nvidia.com>

Convert the DMA direct mapping functions to accept physical addresses
directly instead of page+offset parameters. The functions were already
operating on physical addresses internally, so this change eliminates
the redundant page-to-physical conversion at the API boundary.

The functions dma_direct_map_page() and dma_direct_unmap_page() are
renamed to dma_direct_map_phys() and dma_direct_unmap_phys() respectively,
with their calling convention changed from (struct page *page,
unsigned long offset) to (phys_addr_t phys).

Architecture-specific functions arch_dma_map_page_direct() and
arch_dma_unmap_page_direct() are similarly renamed to
arch_dma_map_phys_direct() and arch_dma_unmap_phys_direct().

The is_pci_p2pdma_page() checks are replaced with DMA_ATTR_MMIO checks
to allow integration with dma_direct_map_resource and dma_direct_map_phys()
is extended to support MMIO path either.

Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
  arch/powerpc/kernel/dma-iommu.c |  4 +--
  include/linux/dma-map-ops.h     |  8 ++---
  kernel/dma/direct.c             |  6 ++--
  kernel/dma/direct.h             | 57 +++++++++++++++++++++------------
  kernel/dma/mapping.c            |  8 ++---
  5 files changed, 49 insertions(+), 34 deletions(-)

<...>

quoted

-	if (unlikely(!dma_capable(dev, dma_addr, size, true)) ||
-	    dma_kmalloc_needs_bounce(dev, size, dir)) {
-		if (is_pci_p2pdma_page(page))
-			return DMA_MAPPING_ERROR;
-		if (is_swiotlb_active(dev))
-			return swiotlb_map(dev, phys, size, dir, attrs);
-
-		dev_WARN_ONCE(dev, 1,
-			     "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",
-			     &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);
-		return DMA_MAPPING_ERROR;
+	if (attrs & DMA_ATTR_MMIO) {
+		dma_addr = phys;
+		if (unlikely(dma_capable(dev, dma_addr, size, false)))

"!dma_capable(dev, dma_addr, size, false)" in the above line.

It took me a while to find this after noticing that this patchset breaks booting some of me test systems.

Ohh, sorry, I overlooked it. Do you expect from me v6?

Thanks