Commit 882cd652 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'dma-mapping-6.15-2025-04-25' of... 

Merge tag 'dma-mapping-6.15-2025-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux

Pull dma-maping fixes from Marek Szyprowski:

 - avoid unused variable warnings (Arnd Bergmann, Marek Szyprowski)

 - add runtume warnings and debug messages for devices with limited DMA
   capabilities (Balbir Singh, Chen-Yu Tsai)

* tag 'dma-mapping-6.15-2025-04-25' of git://git.kernel.org/pub/scm/linux/kernel/git/mszyprowski/linux:
  dma-coherent: Warn if OF reserved memory is beyond current coherent DMA mask
  dma-mapping: Fix warning reported for missing prototype
  dma-mapping: avoid potential unused data compilation warning
  dma/mapping.c: dev_dbg support for dma_addressing_limited
  dma/contiguous: avoid warning about unused size_bytes
parents b22a194c 89461db3

include/linux/dma-mapping.h

+8 −4
Original line number Diff line number Diff line
@@ -629,10 +629,14 @@ static inline int dma_mmap_wc(struct device *dev, 
#else

#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)

#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)

#define dma_unmap_addr(PTR, ADDR_NAME)           (0)

#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)

#define dma_unmap_len(PTR, LEN_NAME)             (0)

#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)

#define dma_unmap_addr(PTR, ADDR_NAME)           \

	({ typeof(PTR) __p __maybe_unused = PTR; 0; })

#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  \

	do { typeof(PTR) __p __maybe_unused = PTR; } while (0)

#define dma_unmap_len(PTR, LEN_NAME)             \

	({ typeof(PTR) __p __maybe_unused = PTR; 0; })

#define dma_unmap_len_set(PTR, LEN_NAME, VAL)    \

	do { typeof(PTR) __p __maybe_unused = PTR; } while (0)

#endif



#endif /* _LINUX_DMA_MAPPING_H */

kernel/dma/coherent.c

+9 −3
Original line number Diff line number Diff line
@@ -336,16 +336,22 @@ static phys_addr_t dma_reserved_default_memory_size __initdata; 


static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)

{

	if (!rmem->priv) {

		struct dma_coherent_mem *mem;

	struct dma_coherent_mem *mem = rmem->priv;



	if (!mem) {

		mem = dma_init_coherent_memory(rmem->base, rmem->base,

					       rmem->size, true);

		if (IS_ERR(mem))

			return PTR_ERR(mem);

		rmem->priv = mem;

	}

	dma_assign_coherent_memory(dev, rmem->priv);



	/* Warn if the device potentially can't use the reserved memory */

	if (mem->device_base + rmem->size - 1 >

	    min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit))

		dev_warn(dev, "reserved memory is beyond device's set DMA address range\n");



	dma_assign_coherent_memory(dev, mem);

	return 0;

}

kernel/dma/contiguous.c

+1 −2
Original line number Diff line number Diff line
@@ -64,8 +64,7 @@ struct cma *dma_contiguous_default_area; 
 * Users, who want to set the size of global CMA area for their system

 * should use cma= kernel parameter.

 */

static const phys_addr_t size_bytes __initconst =

	(phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;

#define size_bytes ((phys_addr_t)CMA_SIZE_MBYTES * SZ_1M)

static phys_addr_t  size_cmdline __initdata = -1;

static phys_addr_t base_cmdline __initdata;

static phys_addr_t limit_cmdline __initdata;

kernel/dma/mapping.c

+17 −8
Original line number Diff line number Diff line
@@ -910,6 +910,19 @@ int dma_set_coherent_mask(struct device *dev, u64 mask) 
}

EXPORT_SYMBOL(dma_set_coherent_mask);



static bool __dma_addressing_limited(struct device *dev)

{

	const struct dma_map_ops *ops = get_dma_ops(dev);



	if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <

			 dma_get_required_mask(dev))

		return true;



	if (unlikely(ops) || use_dma_iommu(dev))

		return false;

	return !dma_direct_all_ram_mapped(dev);

}



/**

 * dma_addressing_limited - return if the device is addressing limited

 * @dev:	device to check
@@ -920,15 +933,11 @@ EXPORT_SYMBOL(dma_set_coherent_mask); 
 */

bool dma_addressing_limited(struct device *dev)

{

	const struct dma_map_ops *ops = get_dma_ops(dev);

	if (!__dma_addressing_limited(dev))

		return false;



	if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <

			 dma_get_required_mask(dev))

	dev_dbg(dev, "device is DMA addressing limited\n");

	return true;



	if (unlikely(ops) || use_dma_iommu(dev))

		return false;

	return !dma_direct_all_ram_mapped(dev);

}

EXPORT_SYMBOL_GPL(dma_addressing_limited);