This is a note to let you know that I've just added the patch titled dma-mapping: Add dma_release_coherent_memory to DMA API to the 5.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dma-mapping-add-dma_release_coherent_memory-to-dma-a.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit a68013e0283c27ea95cecf766ed3f85919c6cbda Author: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx> Date: Fri Apr 22 14:24:35 2022 +0800 dma-mapping: Add dma_release_coherent_memory to DMA API [ Upstream commit e61c451476e61450f6771ce03bbc01210a09be16 ] Add dma_release_coherent_memory to DMA API to allow dma user call it to release dev->dma_mem when the device is removed. Signed-off-by: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx> Acked-by: Christoph Hellwig <hch@xxxxxx> Link: https://lore.kernel.org/r/20220422062436.14384-2-mark-pk.tsai@xxxxxxxxxxxx Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> Stable-dep-of: b07bc2347672 ("dma-mapping: clear dev->dma_mem to NULL after freeing it") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 0d5b06b3a4a6..53db9655efe9 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -166,6 +166,7 @@ static inline void dma_pernuma_cma_reserve(void) { } #ifdef CONFIG_DMA_DECLARE_COHERENT int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, dma_addr_t device_addr, size_t size); +void dma_release_coherent_memory(struct device *dev); int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, dma_addr_t *dma_handle, void **ret); int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr); @@ -177,6 +178,8 @@ static inline int dma_declare_coherent_memory(struct device *dev, { return -ENOSYS; } + +#define dma_release_coherent_memory(dev) (0) #define dma_alloc_from_dev_coherent(dev, size, handle, ret) (0) #define dma_release_from_dev_coherent(dev, order, vaddr) (0) #define dma_mmap_from_dev_coherent(dev, vma, vaddr, order, ret) (0) diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c index 25fc85a7aebe..ca05989d9901 100644 --- a/kernel/dma/coherent.c +++ b/kernel/dma/coherent.c @@ -75,7 +75,7 @@ static struct dma_coherent_mem *dma_init_coherent_memory(phys_addr_t phys_addr, return ERR_PTR(-ENOMEM); } -static void dma_release_coherent_memory(struct dma_coherent_mem *mem) +static void _dma_release_coherent_memory(struct dma_coherent_mem *mem) { if (!mem) return; @@ -127,10 +127,16 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, ret = dma_assign_coherent_memory(dev, mem); if (ret) - dma_release_coherent_memory(mem); + _dma_release_coherent_memory(mem); return ret; } +void dma_release_coherent_memory(struct device *dev) +{ + if (dev) + _dma_release_coherent_memory(dev->dma_mem); +} + static void *__dma_alloc_from_coherent(struct device *dev, struct dma_coherent_mem *mem, ssize_t size, dma_addr_t *dma_handle)