[PATCH 5.4 146/168] RDMA/rw: Fix error flow during RDMA context initialization

Greg Kroah-Hartman
2020-03-10T12:54:33Z

From: Max Gurtovoy <maxg@mellanox.com>

commit 6affca140cbea01f497c4f4e16f1e2be7f74bd04 upstream.

In case the SGL was mapped for P2P DMA operation, we must unmap it using
pci_p2pdma_unmap_sg during the error unwind of rdma_rw_ctx_init()

Fixes: 7f73eac3a713 ("PCI/P2PDMA: Introduce pci_p2pdma_unmap_sg()")
Link: https://lore.kernel.org/r/20200220100819.41860-1-maxg@mellanox.com
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/core/rw.c | 31 ++++++++++++++++++++-----------
1 file changed, 20 insertions(+), 11 deletions(-)

--- a/drivers/infiniband/core/rw.c
+++ b/drivers/infiniband/core/rw.c
@@ -268,6 +268,23 @@ static int rdma_rw_init_single_wr(struct
return 1;
}

+static void rdma_rw_unmap_sg(struct ib_device *dev, struct scatterlist *sg,
+ u32 sg_cnt, enum dma_data_direction dir)
+{
+ if (is_pci_p2pdma_page(sg_page(sg)))
+ pci_p2pdma_unmap_sg(dev->dma_device, sg, sg_cnt, dir);
+ else
+ ib_dma_unmap_sg(dev, sg, sg_cnt, dir);
+}
+
+static int rdma_rw_map_sg(struct ib_device *dev, struct scatterlist *sg,
+ u32 sg_cnt, enum dma_data_direction dir)
+{
+ if (is_pci_p2pdma_page(sg_page(sg)))
+ return pci_p2pdma_map_sg(dev->dma_device, sg, sg_cnt, dir);
+ return ib_dma_map_sg(dev, sg, sg_cnt, dir);
+}
+
/**
* rdma_rw_ctx_init - initialize a RDMA READ/WRITE context
* @ctx: context to initialize
@@ -290,11 +307,7 @@ int rdma_rw_ctx_init(struct rdma_rw_ctx
struct ib_device *dev = qp->pd->device;
int ret;

- if (is_pci_p2pdma_page(sg_page(sg)))
- ret = pci_p2pdma_map_sg(dev->dma_device, sg, sg_cnt, dir);
- else
- ret = ib_dma_map_sg(dev, sg, sg_cnt, dir);
-
+ ret = rdma_rw_map_sg(dev, sg, sg_cnt, dir);
if (!ret)
return -ENOMEM;
sg_cnt = ret;
@@ -333,7 +346,7 @@ int rdma_rw_ctx_init(struct rdma_rw_ctx
return ret;

out_unmap_sg:
- ib_dma_unmap_sg(dev, sg, sg_cnt, dir);
+ rdma_rw_unmap_sg(dev, sg, sg_cnt, dir);
return ret;
}
EXPORT_SYMBOL(rdma_rw_ctx_init);
@@ -583,11 +596,7 @@ void rdma_rw_ctx_destroy(struct rdma_rw_
break;
}

- if (is_pci_p2pdma_page(sg_page(sg)))
- pci_p2pdma_unmap_sg(qp->pd->device->dma_device, sg,
- sg_cnt, dir);
- else
- ib_dma_unmap_sg(qp->pd->device, sg, sg_cnt, dir);
+ rdma_rw_unmap_sg(qp->pd->device, sg, sg_cnt, dir);
}
EXPORT_SYMBOL(rdma_rw_ctx_destroy);