| Message ID | 9515f330b9615de92a1864ab46acbd95e32634b6.1730298502.git.leon@kernel.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Provide a new two step DMA mapping API | expand |
在 2024/10/30 16:12, Leon Romanovsky 写道: > From: Leon Romanovsky <leonro@nvidia.com> > > This patch adds a check if IOVA can be used for the specific > transaction. > > In the new API a DMA mapping transaction is identified by a > struct dma_iova_state, which holds some recomputed information > for the transaction which does not change for each page being > mapped. > > Signed-off-by: Leon Romanovsky <leonro@nvidia.com> > --- > include/linux/dma-mapping.h | 33 +++++++++++++++++++++++++++++++++ > 1 file changed, 33 insertions(+) > > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > index 1524da363734..6075e0708deb 100644 > --- a/include/linux/dma-mapping.h > +++ b/include/linux/dma-mapping.h > @@ -76,6 +76,20 @@ > > #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) > > +struct dma_iova_state { > + size_t __size; > +}; > + > +/* > + * Use the high bit to mark if we used swiotlb for one or more ranges. > + */ > +#define DMA_IOVA_USE_SWIOTLB (1ULL << 63) A trivial problem. In the above macro, using BIT_ULL(63) is better? Zhu Yanjun > + > +static inline size_t dma_iova_size(struct dma_iova_state *state) > +{ > + return state->__size & ~DMA_IOVA_USE_SWIOTLB; > +} > + > #ifdef CONFIG_DMA_API_DEBUG > void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr); > void debug_dma_map_single(struct device *dev, const void *addr, > @@ -281,6 +295,25 @@ static inline int dma_mmap_noncontiguous(struct device *dev, > } > #endif /* CONFIG_HAS_DMA */ > > +#ifdef CONFIG_IOMMU_DMA > +/** > + * dma_use_iova - check if the IOVA API is used for this state > + * @state: IOVA state > + * > + * Return %true if the DMA transfers uses the dma_iova_*() calls or %false if > + * they can't be used. > + */ > +static inline bool dma_use_iova(struct dma_iova_state *state) > +{ > + return state->__size != 0; > +} > +#else /* CONFIG_IOMMU_DMA */ > +static inline bool dma_use_iova(struct dma_iova_state *state) > +{ > + return false; > +} > +#endif /* CONFIG_IOMMU_DMA */ > + > #if defined(CONFIG_HAS_DMA) && defined(CONFIG_DMA_NEED_SYNC) > void __dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size, > enum dma_data_direction dir);
On Sun, Nov 10, 2024 at 04:09:11PM +0100, Zhu Yanjun wrote: > 在 2024/10/30 16:12, Leon Romanovsky 写道: > > From: Leon Romanovsky <leonro@nvidia.com> > > > > This patch adds a check if IOVA can be used for the specific > > transaction. > > > > In the new API a DMA mapping transaction is identified by a > > struct dma_iova_state, which holds some recomputed information > > for the transaction which does not change for each page being > > mapped. > > > > Signed-off-by: Leon Romanovsky <leonro@nvidia.com> > > --- > > include/linux/dma-mapping.h | 33 +++++++++++++++++++++++++++++++++ > > 1 file changed, 33 insertions(+) > > > > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > > index 1524da363734..6075e0708deb 100644 > > --- a/include/linux/dma-mapping.h > > +++ b/include/linux/dma-mapping.h > > @@ -76,6 +76,20 @@ > > #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) > > +struct dma_iova_state { > > + size_t __size; > > +}; > > + > > +/* > > + * Use the high bit to mark if we used swiotlb for one or more ranges. > > + */ > > +#define DMA_IOVA_USE_SWIOTLB (1ULL << 63) > > A trivial problem. > In the above macro, using BIT_ULL(63) is better? You already asked same question and the answer is also the same. https://lore.kernel.org/all/20241103151946.GA99170@unreal/ > > Zhu Yanjun
On Sun, Nov 10, 2024 at 04:09:11PM +0100, Zhu Yanjun wrote: >> + >> +/* >> + * Use the high bit to mark if we used swiotlb for one or more ranges. >> + */ >> +#define DMA_IOVA_USE_SWIOTLB (1ULL << 63) > > A trivial problem. > In the above macro, using BIT_ULL(63) is better? No, and can people please stop suggesting it? That macro is so fucking pointless that it's revolting,
On Mon, Nov 11, 2024 at 2:39 PM Christoph Hellwig <hch@lst.de> wrote: > > On Sun, Nov 10, 2024 at 04:09:11PM +0100, Zhu Yanjun wrote: > >> + > >> +/* > >> + * Use the high bit to mark if we used swiotlb for one or more ranges. > >> + */ > >> +#define DMA_IOVA_USE_SWIOTLB (1ULL << 63) > > > > A trivial problem. > > In the above macro, using BIT_ULL(63) is better? > > No, and can people please stop suggesting it? That macro is so fucking > pointless that it's revolting, Why do you hate this macro so much, have you considered the feelings of the macro author? > >
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 1524da363734..6075e0708deb 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -76,6 +76,20 @@ #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) +struct dma_iova_state { + size_t __size; +}; + +/* + * Use the high bit to mark if we used swiotlb for one or more ranges. + */ +#define DMA_IOVA_USE_SWIOTLB (1ULL << 63) + +static inline size_t dma_iova_size(struct dma_iova_state *state) +{ + return state->__size & ~DMA_IOVA_USE_SWIOTLB; +} + #ifdef CONFIG_DMA_API_DEBUG void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr); void debug_dma_map_single(struct device *dev, const void *addr, @@ -281,6 +295,25 @@ static inline int dma_mmap_noncontiguous(struct device *dev, } #endif /* CONFIG_HAS_DMA */ +#ifdef CONFIG_IOMMU_DMA +/** + * dma_use_iova - check if the IOVA API is used for this state + * @state: IOVA state + * + * Return %true if the DMA transfers uses the dma_iova_*() calls or %false if + * they can't be used. + */ +static inline bool dma_use_iova(struct dma_iova_state *state) +{ + return state->__size != 0; +} +#else /* CONFIG_IOMMU_DMA */ +static inline bool dma_use_iova(struct dma_iova_state *state) +{ + return false; +} +#endif /* CONFIG_IOMMU_DMA */ + #if defined(CONFIG_HAS_DMA) && defined(CONFIG_DMA_NEED_SYNC) void __dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size, enum dma_data_direction dir);