Re: [PATCH v5 10/14] powerpc: Convert to physical address DMA mapping
From: Christophe Leroy <hidden>
Date: 2025-11-14 09:20:34
Also in:
linux-alpha, linux-arm-kernel, linux-iommu, linux-mips, lkml, sparclinux, xen-devel
Le 15/10/2025 à 11:12, Leon Romanovsky a écrit :
From: Leon Romanovsky <leonro@nvidia.com> Adapt PowerPC DMA to use physical addresses in order to prepare code to removal .map_page and .unmap_page. Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Christophe Leroy <redacted> Non fatal comments below.
quoted hunk ↗ jump to hunk
--- arch/powerpc/include/asm/iommu.h | 8 ++++---- arch/powerpc/kernel/dma-iommu.c | 22 ++++++++++----------- arch/powerpc/kernel/iommu.c | 14 +++++++------- arch/powerpc/platforms/ps3/system-bus.c | 33 ++++++++++++++++++-------------- arch/powerpc/platforms/pseries/ibmebus.c | 15 ++++++++------- arch/powerpc/platforms/pseries/vio.c | 21 +++++++++++--------- 6 files changed, 60 insertions(+), 53 deletions(-)diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h index b410021ad4c6..eafdd63cd6c4 100644 --- a/arch/powerpc/include/asm/iommu.h +++ b/arch/powerpc/include/asm/iommu.h@@ -274,12 +274,12 @@ extern void *iommu_alloc_coherent(struct device *dev, struct iommu_table *tbl, unsigned long mask, gfp_t flag, int node); extern void iommu_free_coherent(struct iommu_table *tbl, size_t size, void *vaddr, dma_addr_t dma_handle); -extern dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl, - struct page *page, unsigned long offset, - size_t size, unsigned long mask, +extern dma_addr_t iommu_map_phys(struct device *dev, struct iommu_table *tbl, + phys_addr_t phys, size_t size, + unsigned long mask, enum dma_data_direction direction, unsigned long attrs);
'extern' is pointless for function prototypes. Report from checkpatch: CHECK: extern prototypes should be avoided in .h files #31: FILE: arch/powerpc/include/asm/iommu.h:277: +extern dma_addr_t iommu_map_phys(struct device *dev, struct iommu_table *tbl,
-extern void iommu_unmap_page(struct iommu_table *tbl, dma_addr_t dma_handle, +extern void iommu_unmap_phys(struct iommu_table *tbl, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction, unsigned long attrs);
Same: CHECK: extern prototypes should be avoided in .h files #37: FILE: arch/powerpc/include/asm/iommu.h:282: +extern void iommu_unmap_phys(struct iommu_table *tbl, dma_addr_t dma_handle,
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c index 0359ab72cd3b..aa3689d61917 100644 --- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c@@ -93,28 +93,26 @@ static void dma_iommu_free_coherent(struct device *dev, size_t size, /* Creates TCEs for a user provided buffer. The user buffer must be * contiguous real kernel storage (not vmalloc). The address passed here - * comprises a page address and offset into that page. The dma_addr_t - * returned will point to the same byte within the page as was passed in. + * is a physical address to that page. The dma_addr_t returned will point + * to the same byte within the page as was passed in. */ -static dma_addr_t dma_iommu_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, +static dma_addr_t dma_iommu_map_phys(struct device *dev, phys_addr_t phys, + size_t size, enum dma_data_direction direction, unsigned long attrs) { - return iommu_map_page(dev, get_iommu_table_base(dev), page, offset, - size, dma_get_mask(dev), direction, attrs); + return iommu_map_phys(dev, get_iommu_table_base(dev), phys, size, + dma_get_mask(dev), direction, attrs); } - -static void dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, +static void dma_iommu_unmap_phys(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction, unsigned long attrs) { - iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, direction, + iommu_unmap_phys(get_iommu_table_base(dev), dma_handle, size, direction, attrs); } - static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, int nelems, enum dma_data_direction direction, unsigned long attrs)@@ -211,8 +209,8 @@ const struct dma_map_ops dma_iommu_ops = { .map_sg = dma_iommu_map_sg, .unmap_sg = dma_iommu_unmap_sg, .dma_supported = dma_iommu_dma_supported, - .map_page = dma_iommu_map_page, - .unmap_page = dma_iommu_unmap_page, + .map_phys = dma_iommu_map_phys, + .unmap_phys = dma_iommu_unmap_phys, .get_required_mask = dma_iommu_get_required_mask, .mmap = dma_common_mmap, .get_sgtable = dma_common_get_sgtable,diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c index 244eb4857e7f..6b5f4b72ce97 100644 --- a/arch/powerpc/kernel/iommu.c +++ b/arch/powerpc/kernel/iommu.c@@ -848,12 +848,12 @@ EXPORT_SYMBOL_GPL(iommu_tce_table_put); /* Creates TCEs for a user provided buffer. The user buffer must be * contiguous real kernel storage (not vmalloc). The address passed here - * comprises a page address and offset into that page. The dma_addr_t - * returned will point to the same byte within the page as was passed in. + * is physical address into that page. The dma_addr_t returned will point + * to the same byte within the page as was passed in. */ -dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl, - struct page *page, unsigned long offset, size_t size, - unsigned long mask, enum dma_data_direction direction, +dma_addr_t iommu_map_phys(struct device *dev, struct iommu_table *tbl, + phys_addr_t phys, size_t size, unsigned long mask, + enum dma_data_direction direction, unsigned long attrs) { dma_addr_t dma_handle = DMA_MAPPING_ERROR;@@ -863,7 +863,7 @@ dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl, BUG_ON(direction == DMA_NONE); - vaddr = page_address(page) + offset; + vaddr = phys_to_virt(phys); uaddr = (unsigned long)vaddr; if (tbl) {@@ -890,7 +890,7 @@ dma_addr_t iommu_map_page(struct device *dev, struct iommu_table *tbl, return dma_handle; } -void iommu_unmap_page(struct iommu_table *tbl, dma_addr_t dma_handle, +void iommu_unmap_phys(struct iommu_table *tbl, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction, unsigned long attrs) {diff --git a/arch/powerpc/platforms/ps3/system-bus.c b/arch/powerpc/platforms/ps3/system-bus.c index afbaabf182d0..f4f3477d3a23 100644 --- a/arch/powerpc/platforms/ps3/system-bus.c +++ b/arch/powerpc/platforms/ps3/system-bus.c@@ -551,18 +551,20 @@ static void ps3_free_coherent(struct device *_dev, size_t size, void *vaddr, /* Creates TCEs for a user provided buffer. The user buffer must be * contiguous real kernel storage (not vmalloc). The address passed here - * comprises a page address and offset into that page. The dma_addr_t - * returned will point to the same byte within the page as was passed in. + * is physical address to that hat page. The dma_addr_t returned will point + * to the same byte within the page as was passed in. */ -static dma_addr_t ps3_sb_map_page(struct device *_dev, struct page *page, - unsigned long offset, size_t size, enum dma_data_direction direction, - unsigned long attrs) +static dma_addr_t ps3_sb_map_phys(struct device *_dev, phys_addr_t phys, + size_t size, enum dma_data_direction direction, unsigned long attrs)
CHECK: Alignment should match open parenthesis #151: FILE: arch/powerpc/platforms/ps3/system-bus.c:559: +static dma_addr_t ps3_sb_map_phys(struct device *_dev, phys_addr_t phys, + size_t size, enum dma_data_direction direction, unsigned long attrs)
quoted hunk ↗ jump to hunk
{ struct ps3_system_bus_device *dev = ps3_dev_to_system_bus_dev(_dev); int result; dma_addr_t bus_addr; - void *ptr = page_address(page) + offset; + void *ptr = phys_to_virt(phys); + + if (unlikely(attrs & DMA_ATTR_MMIO)) + return DMA_MAPPING_ERROR; result = ps3_dma_map(dev->d_region, (unsigned long)ptr, size, &bus_addr,@@ -577,8 +579,8 @@ static dma_addr_t ps3_sb_map_page(struct device *_dev, struct page *page, return bus_addr; } -static dma_addr_t ps3_ioc0_map_page(struct device *_dev, struct page *page, - unsigned long offset, size_t size, +static dma_addr_t ps3_ioc0_map_phys(struct device *_dev, phys_addr_t phys, + size_t size, enum dma_data_direction direction, unsigned long attrs) {@@ -586,7 +588,10 @@ static dma_addr_t ps3_ioc0_map_page(struct device *_dev, struct page *page, int result; dma_addr_t bus_addr; u64 iopte_flag; - void *ptr = page_address(page) + offset; + void *ptr = phys_to_virt(phys); + + if (unlikely(attrs & DMA_ATTR_MMIO)) + return DMA_MAPPING_ERROR; iopte_flag = CBE_IOPTE_M; switch (direction) {@@ -613,7 +618,7 @@ static dma_addr_t ps3_ioc0_map_page(struct device *_dev, struct page *page, return bus_addr; } -static void ps3_unmap_page(struct device *_dev, dma_addr_t dma_addr, +static void ps3_unmap_phys(struct device *_dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction direction, unsigned long attrs)
CHECK: Alignment should match open parenthesis #193: FILE: arch/powerpc/platforms/ps3/system-bus.c:622: +static void ps3_unmap_phys(struct device *_dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction direction, unsigned long attrs)
quoted hunk ↗ jump to hunk
{ struct ps3_system_bus_device *dev = ps3_dev_to_system_bus_dev(_dev);@@ -690,8 +695,8 @@ static const struct dma_map_ops ps3_sb_dma_ops = { .map_sg = ps3_sb_map_sg, .unmap_sg = ps3_sb_unmap_sg, .dma_supported = ps3_dma_supported, - .map_page = ps3_sb_map_page, - .unmap_page = ps3_unmap_page, + .map_phys = ps3_sb_map_phys, + .unmap_phys = ps3_unmap_phys, .mmap = dma_common_mmap, .get_sgtable = dma_common_get_sgtable, .alloc_pages_op = dma_common_alloc_pages,@@ -704,8 +709,8 @@ static const struct dma_map_ops ps3_ioc0_dma_ops = { .map_sg = ps3_ioc0_map_sg, .unmap_sg = ps3_ioc0_unmap_sg, .dma_supported = ps3_dma_supported, - .map_page = ps3_ioc0_map_page, - .unmap_page = ps3_unmap_page, + .map_phys = ps3_ioc0_map_phys, + .unmap_phys = ps3_unmap_phys, .mmap = dma_common_mmap, .get_sgtable = dma_common_get_sgtable, .alloc_pages_op = dma_common_alloc_pages,diff --git a/arch/powerpc/platforms/pseries/ibmebus.c b/arch/powerpc/platforms/pseries/ibmebus.c index 3436b0af795e..cad2deb7e70d 100644 --- a/arch/powerpc/platforms/pseries/ibmebus.c +++ b/arch/powerpc/platforms/pseries/ibmebus.c@@ -86,17 +86,18 @@ static void ibmebus_free_coherent(struct device *dev, kfree(vaddr); } -static dma_addr_t ibmebus_map_page(struct device *dev, - struct page *page, - unsigned long offset, +static dma_addr_t ibmebus_map_phys(struct device *dev, phys_addr_t phys, size_t size, enum dma_data_direction direction, unsigned long attrs) { - return (dma_addr_t)(page_address(page) + offset); + if (attrs & DMA_ATTR_MMIO) + return DMA_MAPPING_ERROR; + + return (dma_addr_t)(phys_to_virt(phys)); } -static void ibmebus_unmap_page(struct device *dev, +static void ibmebus_unmap_phys(struct device *dev, dma_addr_t dma_addr, size_t size, enum dma_data_direction direction,@@ -146,8 +147,8 @@ static const struct dma_map_ops ibmebus_dma_ops = { .unmap_sg = ibmebus_unmap_sg, .dma_supported = ibmebus_dma_supported, .get_required_mask = ibmebus_dma_get_required_mask, - .map_page = ibmebus_map_page, - .unmap_page = ibmebus_unmap_page, + .map_phys = ibmebus_map_phys, + .unmap_phys = ibmebus_unmap_phys, }; static int ibmebus_match_path(struct device *dev, const void *data)diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c index ac1d2d2c9a88..18cffac5468f 100644 --- a/arch/powerpc/platforms/pseries/vio.c +++ b/arch/powerpc/platforms/pseries/vio.c@@ -512,18 +512,21 @@ static void vio_dma_iommu_free_coherent(struct device *dev, size_t size, vio_cmo_dealloc(viodev, roundup(size, PAGE_SIZE)); } -static dma_addr_t vio_dma_iommu_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction direction, - unsigned long attrs) +static dma_addr_t vio_dma_iommu_map_phys(struct device *dev, phys_addr_t phys, + size_t size, + enum dma_data_direction direction, + unsigned long attrs) { struct vio_dev *viodev = to_vio_dev(dev); struct iommu_table *tbl = get_iommu_table_base(dev); dma_addr_t ret = DMA_MAPPING_ERROR; + if (unlikely(attrs & DMA_ATTR_MMIO)) + return ret; + if (vio_cmo_alloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl)))) goto out_fail; - ret = iommu_map_page(dev, tbl, page, offset, size, dma_get_mask(dev), + ret = iommu_map_phys(dev, tbl, phys, size, dma_get_mask(dev), direction, attrs);
CHECK: Alignment should match open parenthesis #285: FILE: arch/powerpc/platforms/pseries/vio.c:530: + ret = iommu_map_phys(dev, tbl, phys, size, dma_get_mask(dev), direction, attrs);
quoted hunk ↗ jump to hunk
if (unlikely(ret == DMA_MAPPING_ERROR)) goto out_deallocate;@@ -536,7 +539,7 @@ static dma_addr_t vio_dma_iommu_map_page(struct device *dev, struct page *page, return DMA_MAPPING_ERROR; } -static void vio_dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, +static void vio_dma_iommu_unmap_phys(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction, unsigned long attrs)@@ -544,7 +547,7 @@ static void vio_dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, struct vio_dev *viodev = to_vio_dev(dev); struct iommu_table *tbl = get_iommu_table_base(dev); - iommu_unmap_page(tbl, dma_handle, size, direction, attrs); + iommu_unmap_phys(tbl, dma_handle, size, direction, attrs); vio_cmo_dealloc(viodev, roundup(size, IOMMU_PAGE_SIZE(tbl))); }@@ -605,8 +608,8 @@ static const struct dma_map_ops vio_dma_mapping_ops = { .free = vio_dma_iommu_free_coherent, .map_sg = vio_dma_iommu_map_sg, .unmap_sg = vio_dma_iommu_unmap_sg, - .map_page = vio_dma_iommu_map_page, - .unmap_page = vio_dma_iommu_unmap_page, + .map_phys = vio_dma_iommu_map_phys, + .unmap_phys = vio_dma_iommu_unmap_phys, .dma_supported = dma_iommu_dma_supported, .get_required_mask = dma_iommu_get_required_mask, .mmap = dma_common_mmap,