Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 52d43d81 authored by Sebastian Ott's avatar Sebastian Ott Committed by Martin Schwidefsky
Browse files

s390/pci_dma: improve debugging of errors during dma map 



Improve debugging to find out what went wrong during a failed
dma map/unmap operation.

Signed-off-by: default avatarSebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: default avatarGerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 66728eee

arch/s390/pci/pci_dma.c

+30 −11
Original line number Diff line number Diff line
@@ -269,6 +269,16 @@ static void dma_free_iommu(struct zpci_dev *zdev, unsigned long offset, int size 
	spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);

}



static inline void zpci_err_dma(unsigned long rc, unsigned long addr)

{

	struct {

		unsigned long rc;

		unsigned long addr;

	} __packed data = {rc, addr};



	zpci_err_hex(&data, sizeof(data));

}



static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page,

				     unsigned long offset, size_t size,

				     enum dma_data_direction direction,
@@ -279,33 +289,40 @@ static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page, 
	unsigned long pa = page_to_phys(page) + offset;

	int flags = ZPCI_PTE_VALID;

	dma_addr_t dma_addr;

	int ret;



	/* This rounds up number of pages based on size and offset */

	nr_pages = iommu_num_pages(pa, size, PAGE_SIZE);

	iommu_page_index = dma_alloc_iommu(zdev, nr_pages);

	if (iommu_page_index == -1)

	if (iommu_page_index == -1) {

		ret = -ENOSPC;

		goto out_err;

	}



	/* Use rounded up size */

	size = nr_pages * PAGE_SIZE;



	dma_addr = zdev->start_dma + iommu_page_index * PAGE_SIZE;

	if (dma_addr + size > zdev->end_dma)

	if (dma_addr + size > zdev->end_dma) {

		ret = -ERANGE;

		goto out_free;

	}



	if (direction == DMA_NONE || direction == DMA_TO_DEVICE)

		flags |= ZPCI_TABLE_PROTECTED;



	if (!dma_update_trans(zdev, pa, dma_addr, size, flags)) {

	ret = dma_update_trans(zdev, pa, dma_addr, size, flags);

	if (ret)

		goto out_free;



	atomic64_add(nr_pages, &zdev->mapped_pages);

	return dma_addr + (offset & ~PAGE_MASK);

	}



out_free:

	dma_free_iommu(zdev, iommu_page_index, nr_pages);

out_err:

	zpci_err("map error:\n");

	zpci_err_hex(&pa, sizeof(pa));

	zpci_err_dma(ret, pa);

	return DMA_ERROR_CODE;

}
@@ -315,14 +332,16 @@ static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr, 
{

	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));

	unsigned long iommu_page_index;

	int npages;

	int npages, ret;



	npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);

	dma_addr = dma_addr & PAGE_MASK;

	if (dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,

			     ZPCI_PTE_INVALID)) {

	ret = dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,

			       ZPCI_PTE_INVALID);

	if (ret) {

		zpci_err("unmap error:\n");

		zpci_err_hex(&dma_addr, sizeof(dma_addr));

		zpci_err_dma(ret, dma_addr);

		return;

	}



	atomic64_add(npages, &zdev->unmapped_pages);