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author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-25 13:45:43 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-25 13:45:43 -0800 |
commit | ac1820fb286b552b6885d40ab34f1e59b815f1f1 (patch) | |
tree | b9b4e6dc5df8574e6875e4e2f5f27105addc7812 /lib | |
parent | edccb59429657b09806146339e2b27594c1d1da0 (diff) | |
parent | 0bbb3b7496eabb6779962a998a8a91f4a8e589ff (diff) | |
download | lwn-ac1820fb286b552b6885d40ab34f1e59b815f1f1.tar.gz lwn-ac1820fb286b552b6885d40ab34f1e59b815f1f1.zip |
Merge tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma
Pull rdma DMA mapping updates from Doug Ledford:
"Drop IB DMA mapping code and use core DMA code instead.
Bart Van Assche noted that the ib DMA mapping code was significantly
similar enough to the core DMA mapping code that with a few changes it
was possible to remove the IB DMA mapping code entirely and switch the
RDMA stack to use the core DMA mapping code.
This resulted in a nice set of cleanups, but touched the entire tree
and has been kept separate for that reason."
* tag 'for-next-dma_ops' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma: (37 commits)
IB/rxe, IB/rdmavt: Use dma_virt_ops instead of duplicating it
IB/core: Remove ib_device.dma_device
nvme-rdma: Switch from dma_device to dev.parent
RDS: net: Switch from dma_device to dev.parent
IB/srpt: Modify a debug statement
IB/srp: Switch from dma_device to dev.parent
IB/iser: Switch from dma_device to dev.parent
IB/IPoIB: Switch from dma_device to dev.parent
IB/rxe: Switch from dma_device to dev.parent
IB/vmw_pvrdma: Switch from dma_device to dev.parent
IB/usnic: Switch from dma_device to dev.parent
IB/qib: Switch from dma_device to dev.parent
IB/qedr: Switch from dma_device to dev.parent
IB/ocrdma: Switch from dma_device to dev.parent
IB/nes: Remove a superfluous assignment statement
IB/mthca: Switch from dma_device to dev.parent
IB/mlx5: Switch from dma_device to dev.parent
IB/mlx4: Switch from dma_device to dev.parent
IB/i40iw: Remove a superfluous assignment statement
IB/hns: Switch from dma_device to dev.parent
...
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig | 10 | ||||
-rw-r--r-- | lib/Makefile | 3 | ||||
-rw-r--r-- | lib/dma-noop.c | 4 | ||||
-rw-r--r-- | lib/dma-virt.c | 72 |
4 files changed, 86 insertions, 3 deletions
diff --git a/lib/Kconfig b/lib/Kconfig index fe7e8e175db8..8f69579dfac3 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -394,6 +394,16 @@ config HAS_DMA depends on !NO_DMA default y +config DMA_NOOP_OPS + bool + depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT) + default n + +config DMA_VIRT_OPS + bool + depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT) + default n + config CHECK_SIGNATURE bool diff --git a/lib/Makefile b/lib/Makefile index 445a39c21f46..c9023efbd4ca 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -27,7 +27,8 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \ lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o -lib-$(CONFIG_HAS_DMA) += dma-noop.o +lib-$(CONFIG_DMA_NOOP_OPS) += dma-noop.o +lib-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o lib-y += kobject.o klist.o obj-y += lockref.o diff --git a/lib/dma-noop.c b/lib/dma-noop.c index 3d766e78fbe2..de26c8b68f34 100644 --- a/lib/dma-noop.c +++ b/lib/dma-noop.c @@ -1,7 +1,7 @@ /* * lib/dma-noop.c * - * Simple DMA noop-ops that map 1:1 with memory + * DMA operations that map to physical addresses without flushing memory. */ #include <linux/export.h> #include <linux/mm.h> @@ -64,7 +64,7 @@ static int dma_noop_supported(struct device *dev, u64 mask) return 1; } -struct dma_map_ops dma_noop_ops = { +const struct dma_map_ops dma_noop_ops = { .alloc = dma_noop_alloc, .free = dma_noop_free, .map_page = dma_noop_map_page, diff --git a/lib/dma-virt.c b/lib/dma-virt.c new file mode 100644 index 000000000000..dcd4df1f7174 --- /dev/null +++ b/lib/dma-virt.c @@ -0,0 +1,72 @@ +/* + * lib/dma-virt.c + * + * DMA operations that map to virtual addresses without flushing memory. + */ +#include <linux/export.h> +#include <linux/mm.h> +#include <linux/dma-mapping.h> +#include <linux/scatterlist.h> + +static void *dma_virt_alloc(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs) +{ + void *ret; + + ret = (void *)__get_free_pages(gfp, get_order(size)); + if (ret) + *dma_handle = (uintptr_t)ret; + return ret; +} + +static void dma_virt_free(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t dma_addr, + unsigned long attrs) +{ + free_pages((unsigned long)cpu_addr, get_order(size)); +} + +static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + return (uintptr_t)(page_address(page) + offset); +} + +static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, + unsigned long attrs) +{ + int i; + struct scatterlist *sg; + + for_each_sg(sgl, sg, nents, i) { + BUG_ON(!sg_page(sg)); + sg_dma_address(sg) = (uintptr_t)sg_virt(sg); + sg_dma_len(sg) = sg->length; + } + + return nents; +} + +static int dma_virt_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return false; +} + +static int dma_virt_supported(struct device *dev, u64 mask) +{ + return true; +} + +const struct dma_map_ops dma_virt_ops = { + .alloc = dma_virt_alloc, + .free = dma_virt_free, + .map_page = dma_virt_map_page, + .map_sg = dma_virt_map_sg, + .mapping_error = dma_virt_mapping_error, + .dma_supported = dma_virt_supported, +}; +EXPORT_SYMBOL(dma_virt_ops); |