summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRobin Murphy <robin.murphy@arm.com>2023-06-12 18:31:56 +0300
committerAndrew Morton <akpm@linux-foundation.org>2023-06-20 02:19:22 +0300
commitaf2880ec44021d32cc72a5aa7c5d7d7beaa722d3 (patch)
tree8d3bb64042594fd30da9766d9bb458d37eca890f
parent9382bc44b5f58ccee375f08f518e53c0280051dc (diff)
downloadlinux-af2880ec44021d32cc72a5aa7c5d7d7beaa722d3.tar.xz
scatterlist: add dedicated config for DMA flags
The DMA flags field will be useful for users beyond PCI P2P, so upgrade to its own dedicated config option. [catalin.marinas@arm.com: use #ifdef CONFIG_NEED_SG_DMA_FLAGS in scatterlist.h] [catalin.marinas@arm.com: update PCI_P2PDMA dma_flags comment in scatterlist.h] Link: https://lkml.kernel.org/r/20230612153201.554742-13-catalin.marinas@arm.com Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Isaac J. Manjarres <isaacmanjarres@google.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Jerry Snitselaar <jsnitsel@redhat.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Brown <broonie@kernel.org> Cc: Mike Snitzer <snitzer@kernel.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r--drivers/pci/Kconfig1
-rw-r--r--include/linux/scatterlist.h13
-rw-r--r--kernel/dma/Kconfig3
3 files changed, 10 insertions, 7 deletions
diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
index 9309f2469b41..3c07d8d214b3 100644
--- a/drivers/pci/Kconfig
+++ b/drivers/pci/Kconfig
@@ -168,6 +168,7 @@ config PCI_P2PDMA
#
depends on 64BIT
select GENERIC_ALLOCATOR
+ select NEED_SG_DMA_FLAGS
help
Enableѕ drivers to do PCI peer-to-peer transactions to and from
BARs that are exposed in other devices that are the part of
diff --git a/include/linux/scatterlist.h b/include/linux/scatterlist.h
index 375a5e90d86a..19833fd4113b 100644
--- a/include/linux/scatterlist.h
+++ b/include/linux/scatterlist.h
@@ -16,7 +16,7 @@ struct scatterlist {
#ifdef CONFIG_NEED_SG_DMA_LENGTH
unsigned int dma_length;
#endif
-#ifdef CONFIG_PCI_P2PDMA
+#ifdef CONFIG_NEED_SG_DMA_FLAGS
unsigned int dma_flags;
#endif
};
@@ -249,12 +249,11 @@ static inline void sg_unmark_end(struct scatterlist *sg)
}
/*
- * CONFGI_PCI_P2PDMA depends on CONFIG_64BIT which means there is 4 bytes
- * in struct scatterlist (assuming also CONFIG_NEED_SG_DMA_LENGTH is set).
- * Use this padding for DMA flags bits to indicate when a specific
- * dma address is a bus address.
+ * One 64-bit architectures there is a 4-byte padding in struct scatterlist
+ * (assuming also CONFIG_NEED_SG_DMA_LENGTH is set). Use this padding for DMA
+ * flags bits to indicate when a specific dma address is a bus address.
*/
-#ifdef CONFIG_PCI_P2PDMA
+#ifdef CONFIG_NEED_SG_DMA_FLAGS
#define SG_DMA_BUS_ADDRESS (1 << 0)
@@ -312,7 +311,7 @@ static inline void sg_dma_unmark_bus_address(struct scatterlist *sg)
{
}
-#endif
+#endif /* CONFIG_NEED_SG_DMA_FLAGS */
/**
* sg_phys - Return physical address of an sg entry
diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig
index 6677d0e64d27..acc6f231259c 100644
--- a/kernel/dma/Kconfig
+++ b/kernel/dma/Kconfig
@@ -24,6 +24,9 @@ config DMA_OPS_BYPASS
config ARCH_HAS_DMA_MAP_DIRECT
bool
+config NEED_SG_DMA_FLAGS
+ bool
+
config NEED_SG_DMA_LENGTH
bool