[PATCH 17/25] PCI/P2PDMA: use the dev_pagemap internal refcount

Christoph Hellwig
2019-06-26T12:28:16Z

The functionality is identical to the one currently open coded in
p2pdma.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/pci/p2pdma.c | 57 ++++----------------------------------------
1 file changed, 4 insertions(+), 53 deletions(-)

diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c
index ebd8ce3bba2e..608f84df604a 100644
--- a/drivers/pci/p2pdma.c
+++ b/drivers/pci/p2pdma.c
@@ -24,12 +24,6 @@ struct pci_p2pdma {
bool p2pmem_published;
};

-struct p2pdma_pagemap {
- struct dev_pagemap pgmap;
- struct percpu_ref ref;
- struct completion ref_done;
-};
-
static ssize_t size_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@@ -78,32 +72,6 @@ static const struct attribute_group p2pmem_group = {
.name = "p2pmem",
};

-static struct p2pdma_pagemap *to_p2p_pgmap(struct percpu_ref *ref)
-{
- return container_of(ref, struct p2pdma_pagemap, ref);
-}
-
-static void pci_p2pdma_percpu_release(struct percpu_ref *ref)
-{
- struct p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(ref);
-
- complete(&p2p_pgmap->ref_done);
-}
-
-static void pci_p2pdma_percpu_kill(struct dev_pagemap *pgmap)
-{
- percpu_ref_kill(pgmap->ref);
-}
-
-static void pci_p2pdma_percpu_cleanup(struct dev_pagemap *pgmap)
-{
- struct p2pdma_pagemap *p2p_pgmap =
- container_of(pgmap, struct p2pdma_pagemap, pgmap);
-
- wait_for_completion(&p2p_pgmap->ref_done);
- percpu_ref_exit(&p2p_pgmap->ref);
-}
-
static void pci_p2pdma_release(void *data)
{
struct pci_dev *pdev = data;
@@ -153,11 +121,6 @@ static int pci_p2pdma_setup(struct pci_dev *pdev)
return error;
}

-static const struct dev_pagemap_ops pci_p2pdma_pagemap_ops = {
- .kill = pci_p2pdma_percpu_kill,
- .cleanup = pci_p2pdma_percpu_cleanup,
-};
-
/**
* pci_p2pdma_add_resource - add memory for use as p2p memory
* @pdev: the device to add the memory to
@@ -171,7 +134,6 @@ static const struct dev_pagemap_ops pci_p2pdma_pagemap_ops = {
int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
u64 offset)
{
- struct p2pdma_pagemap *p2p_pgmap;
struct dev_pagemap *pgmap;
void *addr;
int error;
@@ -194,26 +156,15 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
return error;
}

- p2p_pgmap = devm_kzalloc(&pdev->dev, sizeof(*p2p_pgmap), GFP_KERNEL);
- if (!p2p_pgmap)
+ pgmap = devm_kzalloc(&pdev->dev, sizeof(*pgmap), GFP_KERNEL);
+ if (!pgmap)
return -ENOMEM;
-
- init_completion(&p2p_pgmap->ref_done);
- error = percpu_ref_init(&p2p_pgmap->ref,
- pci_p2pdma_percpu_release, 0, GFP_KERNEL);
- if (error)
- goto pgmap_free;
-
- pgmap = &p2p_pgmap->pgmap;
-
pgmap->res.start = pci_resource_start(pdev, bar) + offset;
pgmap->res.end = pgmap->res.start + size - 1;
pgmap->res.flags = pci_resource_flags(pdev, bar);
- pgmap->ref = &p2p_pgmap->ref;
pgmap->type = MEMORY_DEVICE_PCI_P2PDMA;
pgmap->pci_p2pdma_bus_offset = pci_bus_address(pdev, bar) -
pci_resource_start(pdev, bar);
- pgmap->ops = &pci_p2pdma_pagemap_ops;

addr = devm_memremap_pages(&pdev->dev, pgmap);
if (IS_ERR(addr)) {
@@ -224,7 +175,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
error = gen_pool_add_owner(pdev->p2pdma->pool, (unsigned long)addr,
pci_bus_address(pdev, bar) + offset,
resource_size(&pgmap->res), dev_to_node(&pdev->dev),
- &p2p_pgmap->ref);
+ pgmap->ref);
if (error)
goto pages_free;

@@ -236,7 +187,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
pages_free:
devm_memunmap_pages(&pdev->dev, pgmap);
pgmap_free:
- devm_kfree(&pdev->dev, p2p_pgmap);
+ devm_kfree(&pdev->dev, pgmap);
return error;
}
EXPORT_SYMBOL_GPL(pci_p2pdma_add_resource);
--
2.20.1