PCI/P2PDMA: Factor out __pci_p2pdma_map_sg()

Factor out the bus-only mapping into its own static function.  No
functional changes. The original pci_p2pdma_map_sg_attrs() will be used to
decide whether this is an appropriate way to map.

Link: https://lore.kernel.org/r/20190730163545.4915-11-logang@deltatee.com
Link: https://lore.kernel.org/r/20190812173048.9186-11-logang@deltatee.com
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Logan Gunthorpe 2019-08-12 11:30:44 -06:00 committed by Bjorn Helgaas
parent 7f73eac3a7
commit 142c242e6f

View File

@ -792,6 +792,33 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
}
EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
static int __pci_p2pdma_map_sg(struct pci_p2pdma_pagemap *p2p_pgmap,
struct device *dev, struct scatterlist *sg, int nents)
{
struct scatterlist *s;
phys_addr_t paddr;
int i;
/*
* p2pdma mappings are not compatible with devices that use
* dma_virt_ops. If the upper layers do the right thing
* this should never happen because it will be prevented
* by the check in pci_p2pdma_distance_many()
*/
if (WARN_ON_ONCE(IS_ENABLED(CONFIG_DMA_VIRT_OPS) &&
dev->dma_ops == &dma_virt_ops))
return 0;
for_each_sg(sg, s, nents, i) {
paddr = sg_phys(s);
s->dma_address = paddr - p2p_pgmap->bus_offset;
sg_dma_len(s) = s->length;
}
return nents;
}
/**
* pci_p2pdma_map_sg - map a PCI peer-to-peer scatterlist for DMA
* @dev: device doing the DMA request
@ -808,30 +835,10 @@ EXPORT_SYMBOL_GPL(pci_p2pmem_publish);
int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir, unsigned long attrs)
{
struct pci_p2pdma_pagemap *p2p_pgmap;
struct scatterlist *s;
phys_addr_t paddr;
int i;
struct pci_p2pdma_pagemap *p2p_pgmap =
to_p2p_pgmap(sg_page(sg)->pgmap);
/*
* p2pdma mappings are not compatible with devices that use
* dma_virt_ops. If the upper layers do the right thing
* this should never happen because it will be prevented
* by the check in pci_p2pdma_distance_many()
*/
if (WARN_ON_ONCE(IS_ENABLED(CONFIG_DMA_VIRT_OPS) &&
dev->dma_ops == &dma_virt_ops))
return 0;
for_each_sg(sg, s, nents, i) {
p2p_pgmap = to_p2p_pgmap(sg_page(s)->pgmap);
paddr = sg_phys(s);
s->dma_address = paddr - p2p_pgmap->bus_offset;
sg_dma_len(s) = s->length;
}
return nents;
return __pci_p2pdma_map_sg(p2p_pgmap, dev, sg, nents);
}
EXPORT_SYMBOL_GPL(pci_p2pdma_map_sg_attrs);