There are no more users of the struct pages that back P2P memory, so convert the devm_memremap_pages() call to devm_memremap() to remove them.
The percpu_ref and completion are retained in struct p2pdma to track when there is no memory allocated out of the genpool and it is safe to free it. Signed-off-by: Logan Gunthorpe <[email protected]> --- drivers/pci/p2pdma.c | 107 +++++++++++++------------------------------ 1 file changed, 33 insertions(+), 74 deletions(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 9b82e13f802c..83d93911f792 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -22,10 +22,6 @@ struct pci_p2pdma { struct gen_pool *pool; bool p2pmem_published; -}; - -struct p2pdma_pagemap { - struct dev_pagemap pgmap; struct percpu_ref ref; struct completion ref_done; }; @@ -78,29 +74,12 @@ 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); + struct pci_p2pdma *p2pdma = + container_of(ref, struct pci_p2pdma, ref); - complete(&p2p_pgmap->ref_done); -} - -static void pci_p2pdma_percpu_kill(struct percpu_ref *ref) -{ - percpu_ref_kill(ref); -} - -static void pci_p2pdma_percpu_cleanup(struct percpu_ref *ref) -{ - struct p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(ref); - - wait_for_completion(&p2p_pgmap->ref_done); - percpu_ref_exit(&p2p_pgmap->ref); + complete(&p2pdma->ref_done); } static void pci_p2pdma_release(void *data) @@ -111,6 +90,10 @@ static void pci_p2pdma_release(void *data) if (!p2pdma) return; + percpu_ref_kill(&p2pdma->ref); + wait_for_completion(&p2pdma->ref_done); + percpu_ref_exit(&p2pdma->ref); + /* Flush and disable pci_alloc_p2p_mem() */ pdev->p2pdma = NULL; synchronize_rcu(); @@ -128,10 +111,17 @@ static int pci_p2pdma_setup(struct pci_dev *pdev) if (!p2p) return -ENOMEM; + init_completion(&p2p->ref_done); + p2p->pool = gen_pool_create(PAGE_SHIFT, dev_to_node(&pdev->dev)); if (!p2p->pool) goto out; + error = percpu_ref_init(&p2p->ref, pci_p2pdma_percpu_release, 0, + GFP_KERNEL); + if (error) + goto out_pool_destroy; + error = devm_add_action_or_reset(&pdev->dev, pci_p2pdma_release, pdev); if (error) goto out_pool_destroy; @@ -165,8 +155,7 @@ static int pci_p2pdma_setup(struct pci_dev *pdev) 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; + struct resource res; void *addr; int error; @@ -188,50 +177,26 @@ 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) - return -ENOMEM; + res.start = pci_resource_start(pdev, bar) + offset; + res.end = res.start + size - 1; + res.flags = pci_resource_flags(pdev, bar); - 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->kill = pci_p2pdma_percpu_kill; - pgmap->cleanup = pci_p2pdma_percpu_cleanup; - - addr = devm_memremap_pages(&pdev->dev, pgmap); - if (IS_ERR(addr)) { - error = PTR_ERR(addr); - goto pgmap_free; - } + addr = devm_memremap(&pdev->dev, res.start, size, MEMREMAP_WC); + if (IS_ERR(addr)) + return PTR_ERR(addr); - 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); + error = gen_pool_add_virt(pdev->p2pdma->pool, (unsigned long)addr, + pci_bus_address(pdev, bar) + offset, size, + dev_to_node(&pdev->dev)); if (error) goto pages_free; - pci_info(pdev, "added peer-to-peer DMA memory %pR\n", - &pgmap->res); + pci_info(pdev, "added peer-to-peer DMA memory %pR\n", &res); return 0; pages_free: - devm_memunmap_pages(&pdev->dev, pgmap); -pgmap_free: - devm_kfree(&pdev->dev, p2p_pgmap); + devm_memunmap(&pdev->dev, addr); return error; } EXPORT_SYMBOL_GPL(pci_p2pdma_add_resource); @@ -601,7 +566,6 @@ EXPORT_SYMBOL_GPL(pci_p2pmem_find_many); void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size) { void *ret = NULL; - struct percpu_ref *ref; /* * Pairs with synchronize_rcu() in pci_p2pdma_release() to @@ -612,16 +576,13 @@ void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size) if (unlikely(!pdev->p2pdma)) goto out; - ret = (void *)gen_pool_alloc_owner(pdev->p2pdma->pool, size, - (void **) &ref); - if (!ret) + if (unlikely(!percpu_ref_tryget_live(&pdev->p2pdma->ref))) goto out; - if (unlikely(!percpu_ref_tryget_live(ref))) { - gen_pool_free(pdev->p2pdma->pool, (unsigned long) ret, size); - ret = NULL; - goto out; - } + ret = (void *)gen_pool_alloc(pdev->p2pdma->pool, size); + if (!ret) + percpu_ref_put(&pdev->p2pdma->ref); + out: rcu_read_unlock(); return ret; @@ -636,11 +597,9 @@ EXPORT_SYMBOL_GPL(pci_alloc_p2pmem); */ void pci_free_p2pmem(struct pci_dev *pdev, void *addr, size_t size) { - struct percpu_ref *ref; + gen_pool_free(pdev->p2pdma->pool, (uintptr_t)addr, size); - gen_pool_free_owner(pdev->p2pdma->pool, (uintptr_t)addr, size, - (void **) &ref); - percpu_ref_put(ref); + percpu_ref_put(&pdev->p2pdma->ref); } EXPORT_SYMBOL_GPL(pci_free_p2pmem); -- 2.20.1
