On Tue, Feb 04, 2020 at 07:32:04AM +0100, Christoph Hellwig wrote: > Untangle the way how dma_direct_map_page calls into swiotlb to be able > to properly report errors where the swiotlb DMA address overflows the > mask separately from overflows in the !swiotlb case. This means that > siotlb_map now has to do a little more work that duplicates > dma_direct_map_page, but doing so greatly simplifies the calling > convention. > > Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Konrad Rzeszutek Wilk <[email protected]> Acked-by: Konrad Rzeszutek Wilk <[email protected]> (Pick whichever tag you want :-)) > --- > include/linux/swiotlb.h | 11 +++-------- > kernel/dma/direct.c | 16 +++++++-------- > kernel/dma/swiotlb.c | 43 +++++++++++++++++++++++------------------ > 3 files changed, 34 insertions(+), 36 deletions(-) > > diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h > index cde3dc18e21a..046bb94bd4d6 100644 > --- a/include/linux/swiotlb.h > +++ b/include/linux/swiotlb.h > @@ -64,6 +64,9 @@ extern void swiotlb_tbl_sync_single(struct device *hwdev, > size_t size, enum dma_data_direction dir, > enum dma_sync_target target); > > +dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys, > + size_t size, enum dma_data_direction dir, unsigned long attrs); > + > #ifdef CONFIG_SWIOTLB > extern enum swiotlb_force swiotlb_force; > extern phys_addr_t io_tlb_start, io_tlb_end; > @@ -73,8 +76,6 @@ static inline bool is_swiotlb_buffer(phys_addr_t paddr) > return paddr >= io_tlb_start && paddr < io_tlb_end; > } > > -bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr, > - size_t size, enum dma_data_direction dir, unsigned long attrs); > void __init swiotlb_exit(void); > unsigned int swiotlb_max_segment(void); > size_t swiotlb_max_mapping_size(struct device *dev); > @@ -85,12 +86,6 @@ static inline bool is_swiotlb_buffer(phys_addr_t paddr) > { > return false; > } > -static inline bool swiotlb_map(struct device *dev, phys_addr_t *phys, > - dma_addr_t *dma_addr, size_t size, enum dma_data_direction dir, > - unsigned long attrs) > -{ > - return false; > -} > static inline void swiotlb_exit(void) > { > } > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 6af7ae83c4ad..82ad50aaf42c 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -357,13 +357,6 @@ void dma_direct_unmap_sg(struct device *dev, struct > scatterlist *sgl, > EXPORT_SYMBOL(dma_direct_unmap_sg); > #endif > > -static inline bool dma_direct_possible(struct device *dev, dma_addr_t > dma_addr, > - size_t size) > -{ > - return swiotlb_force != SWIOTLB_FORCE && > - dma_capable(dev, dma_addr, size, true); > -} > - > dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, > unsigned long offset, size_t size, enum dma_data_direction dir, > unsigned long attrs) > @@ -371,8 +364,13 @@ dma_addr_t dma_direct_map_page(struct device *dev, > struct page *page, > phys_addr_t phys = page_to_phys(page) + offset; > dma_addr_t dma_addr = phys_to_dma(dev, phys); > > - if (unlikely(!dma_direct_possible(dev, dma_addr, size)) && > - !swiotlb_map(dev, &phys, &dma_addr, size, dir, attrs)) { > + if (unlikely(swiotlb_force == SWIOTLB_FORCE)) > + return swiotlb_map(dev, phys, size, dir, attrs); > + > + if (unlikely(!dma_capable(dev, dma_addr, size, true))) { > + if (swiotlb_force != SWIOTLB_NO_FORCE) > + return swiotlb_map(dev, phys, size, dir, attrs); > + > report_addr(dev, dma_addr, size); > return DMA_MAPPING_ERROR; > } > diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c > index 9280d6f8271e..589bb9a40f21 100644 > --- a/kernel/dma/swiotlb.c > +++ b/kernel/dma/swiotlb.c > @@ -22,6 +22,7 @@ > > #include <linux/cache.h> > #include <linux/dma-direct.h> > +#include <linux/dma-noncoherent.h> > #include <linux/mm.h> > #include <linux/export.h> > #include <linux/spinlock.h> > @@ -656,35 +657,39 @@ void swiotlb_tbl_sync_single(struct device *hwdev, > phys_addr_t tlb_addr, > } > > /* > - * Create a swiotlb mapping for the buffer at @phys, and in case of DMAing > + * Create a swiotlb mapping for the buffer at @paddr, and in case of DMAing > * to the device copy the data into it as well. > */ > -bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr, > - size_t size, enum dma_data_direction dir, unsigned long attrs) > +dma_addr_t swiotlb_map(struct device *dev, phys_addr_t paddr, size_t size, > + enum dma_data_direction dir, unsigned long attrs) > { > - trace_swiotlb_bounced(dev, *dma_addr, size, swiotlb_force); > + phys_addr_t swiotlb_addr; > + dma_addr_t dma_addr; > > - if (unlikely(swiotlb_force == SWIOTLB_NO_FORCE)) { > - dev_warn_ratelimited(dev, > - "Cannot do DMA to address %pa\n", phys); > - return false; > - } > + trace_swiotlb_bounced(dev, phys_to_dma(dev, paddr), size, > + swiotlb_force); > > - /* Oh well, have to allocate and map a bounce buffer. */ > - *phys = swiotlb_tbl_map_single(dev, __phys_to_dma(dev, io_tlb_start), > - *phys, size, size, dir, attrs); > - if (*phys == (phys_addr_t)DMA_MAPPING_ERROR) > - return false; > + swiotlb_addr = swiotlb_tbl_map_single(dev, > + __phys_to_dma(dev, io_tlb_start), > + paddr, size, size, dir, attrs); > + if (swiotlb_addr == (phys_addr_t)DMA_MAPPING_ERROR) > + return DMA_MAPPING_ERROR; > > /* Ensure that the address returned is DMA'ble */ > - *dma_addr = __phys_to_dma(dev, *phys); > - if (unlikely(!dma_capable(dev, *dma_addr, size, true))) { > - swiotlb_tbl_unmap_single(dev, *phys, size, size, dir, > + dma_addr = __phys_to_dma(dev, swiotlb_addr); > + if (unlikely(!dma_capable(dev, dma_addr, size, true))) { > + swiotlb_tbl_unmap_single(dev, swiotlb_addr, size, size, dir, > attrs | DMA_ATTR_SKIP_CPU_SYNC); > - return false; > + dev_err_once(dev, > + "swiotlb addr %pad+%zu overflow (mask %llx, bus limit > %llx).\n", > + &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit); > + WARN_ON_ONCE(1); > + return DMA_MAPPING_ERROR; > } > > - return true; > + if (!dev_is_dma_coherent(dev) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) > + arch_sync_dma_for_device(swiotlb_addr, size, dir); > + return dma_addr; > } > > size_t swiotlb_max_mapping_size(struct device *dev) > -- > 2.24.1 > _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
