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| author | Frederic Barrat <fbarrat@linux.ibm.com> | 2021-05-26 16:45:40 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-06-01 11:17:08 +1000 |
| commit | 59cc84c802eb923805e7bba425976a3df5ce35d8 (patch) | |
| tree | 3d84115b08a05ae52da71ebafaa50eb69f3904ba /arch | |
| parent | 1438709e6328925ef496dafd467dbd0353137434 (diff) | |
| download | linux-59cc84c802eb923805e7bba425976a3df5ce35d8.tar.gz | |
Revert "powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs"
This reverts commit 3c0468d4451eb6b4f6604370639f163f9637a479.
That commit was breaking alignment guarantees for the DMA address when
allocating coherent mappings, as described in
Documentation/core-api/dma-api-howto.rst
It was also noticed by Mellanox' driver:
[ 1515.763621] mlx5_core c002:01:00.0: mlx5_frag_buf_alloc_node:146:(pid 13402): unexpected map alignment: 0x0800000000c61000, page_shift=16
[ 1515.763635] mlx5_core c002:01:00.0: mlx5_cqwq_create:181:(pid
13402): mlx5_frag_buf_alloc_node() failed, -12
Fixes: 3c0468d4451e ("powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs")
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210526144540.117795-1-fbarrat@linux.ibm.com
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/iommu.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 57d6b85e9b96..2af89a5e379f 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c @@ -898,7 +898,6 @@ void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl, unsigned int order; unsigned int nio_pages, io_order; struct page *page; - size_t size_io = size; size = PAGE_ALIGN(size); order = get_order(size); @@ -925,9 +924,8 @@ void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl, memset(ret, 0, size); /* Set up tces to cover the allocated range */ - size_io = IOMMU_PAGE_ALIGN(size_io, tbl); - nio_pages = size_io >> tbl->it_page_shift; - io_order = get_iommu_order(size_io, tbl); + nio_pages = size >> tbl->it_page_shift; + io_order = get_iommu_order(size, tbl); mapping = iommu_alloc(dev, tbl, ret, nio_pages, DMA_BIDIRECTIONAL, mask >> tbl->it_page_shift, io_order, 0); if (mapping == DMA_MAPPING_ERROR) { @@ -942,9 +940,10 @@ void iommu_free_coherent(struct iommu_table *tbl, size_t size, void *vaddr, dma_addr_t dma_handle) { if (tbl) { - size_t size_io = IOMMU_PAGE_ALIGN(size, tbl); - unsigned int nio_pages = size_io >> tbl->it_page_shift; + unsigned int nio_pages; + size = PAGE_ALIGN(size); + nio_pages = size >> tbl->it_page_shift; iommu_free(tbl, dma_handle, nio_pages); size = PAGE_ALIGN(size); free_pages((unsigned long)vaddr, get_order(size)); |