[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20210408170123.8788-10-logang@deltatee.com>
Date: Thu, 8 Apr 2021 11:01:16 -0600
From: Logan Gunthorpe <logang@...tatee.com>
To: linux-kernel@...r.kernel.org, linux-nvme@...ts.infradead.org,
linux-block@...r.kernel.org, linux-pci@...r.kernel.org,
linux-mm@...ck.org, iommu@...ts.linux-foundation.org
Cc: Stephen Bates <sbates@...thlin.com>,
Christoph Hellwig <hch@....de>,
Dan Williams <dan.j.williams@...el.com>,
Jason Gunthorpe <jgg@...pe.ca>,
Christian König <christian.koenig@....com>,
John Hubbard <jhubbard@...dia.com>,
Don Dutile <ddutile@...hat.com>,
Matthew Wilcox <willy@...radead.org>,
Daniel Vetter <daniel.vetter@...ll.ch>,
Jakowski Andrzej <andrzej.jakowski@...el.com>,
Minturn Dave B <dave.b.minturn@...el.com>,
Jason Ekstrand <jason@...kstrand.net>,
Dave Hansen <dave.hansen@...ux.intel.com>,
Xiong Jianxin <jianxin.xiong@...el.com>,
Bjorn Helgaas <helgaas@...nel.org>,
Ira Weiny <ira.weiny@...el.com>,
Robin Murphy <robin.murphy@....com>,
Logan Gunthorpe <logang@...tatee.com>
Subject: [PATCH 09/16] dma-direct: Support PCI P2PDMA pages in dma-direct map_sg
Add PCI P2PDMA support for dma_direct_map_sg() so that it can map
PCI P2PDMA pages directly without a hack in the callers. This allows
for heterogeneous SGLs that contain both P2PDMA and regular pages.
SGL segments that contain PCI bus addresses are marked with
sg_mark_pci_p2pdma() and are ignored when unmapped.
Signed-off-by: Logan Gunthorpe <logang@...tatee.com>
---
kernel/dma/direct.c | 25 ++++++++++++++++++++++---
1 file changed, 22 insertions(+), 3 deletions(-)
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 002268262c9a..108dfb4ecbd5 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -13,6 +13,7 @@
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
#include <linux/slab.h>
+#include <linux/pci-p2pdma.h>
#include "direct.h"
/*
@@ -387,19 +388,37 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
struct scatterlist *sg;
int i;
- for_each_sg(sgl, sg, nents, i)
+ for_each_sg(sgl, sg, nents, i) {
+ if (sg_is_pci_p2pdma(sg)) {
+ sg_unmark_pci_p2pdma(sg);
+ continue;
+ }
+
dma_direct_unmap_page(dev, sg->dma_address, sg_dma_len(sg), dir,
attrs);
+ }
}
#endif
int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs)
{
- int i;
+ struct pci_p2pdma_map_state p2pdma_state = {};
struct scatterlist *sg;
+ int i, ret = 0;
for_each_sg(sgl, sg, nents, i) {
+ if (is_pci_p2pdma_page(sg_page(sg))) {
+ ret = pci_p2pdma_map_segment(&p2pdma_state, dev, sg,
+ attrs);
+ if (ret < 0) {
+ goto out_unmap;
+ } else if (ret) {
+ ret = 0;
+ continue;
+ }
+ }
+
sg->dma_address = dma_direct_map_page(dev, sg_page(sg),
sg->offset, sg->length, dir, attrs);
if (sg->dma_address == DMA_MAPPING_ERROR)
@@ -411,7 +430,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
out_unmap:
dma_direct_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC);
- return 0;
+ return ret;
}
dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
--
2.20.1
Powered by blists - more mailing lists