From b80892ca022e9eb484771a66eb68e12364695a2a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 28 Oct 2021 17:10:17 +0200 Subject: [PATCH] memremap: remove support for external pgmap refcounts No driver is left using the external pgmap refcount, so remove the code to support it. Signed-off-by: Christoph Hellwig Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20211028151017.50234-1-hch@lst.de Signed-off-by: Dan Williams --- drivers/pci/p2pdma.c | 2 +- include/linux/memremap.h | 18 ++-------- mm/memremap.c | 59 +++++++------------------------ tools/testing/nvdimm/test/iomap.c | 39 ++++++-------------- 4 files changed, 26 insertions(+), 92 deletions(-) diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 8d47cb7218d1..454d5f6f16ff 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -219,7 +219,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, error = gen_pool_add_owner(p2pdma->pool, (unsigned long)addr, pci_bus_address(pdev, bar) + offset, range_len(&pgmap->range), dev_to_node(&pdev->dev), - pgmap->ref); + &pgmap->ref); if (error) goto pages_free; diff --git a/include/linux/memremap.h b/include/linux/memremap.h index c0e9d35889e8..a8bc588fe7aa 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -72,16 +72,6 @@ struct dev_pagemap_ops { */ void (*page_free)(struct page *page); - /* - * Transition the refcount in struct dev_pagemap to the dead state. - */ - void (*kill)(struct dev_pagemap *pgmap); - - /* - * Wait for refcount in struct dev_pagemap to be idle and reap it. - */ - void (*cleanup)(struct dev_pagemap *pgmap); - /* * Used for private (un-addressable) device memory only. Must migrate * the page back to a CPU accessible page. @@ -95,8 +85,7 @@ struct dev_pagemap_ops { * struct dev_pagemap - metadata for ZONE_DEVICE mappings * @altmap: pre-allocated/reserved memory for vmemmap allocations * @ref: reference count that pins the devm_memremap_pages() mapping - * @internal_ref: internal reference if @ref is not provided by the caller - * @done: completion for @internal_ref + * @done: completion for @ref * @type: memory type: see MEMORY_* in memory_hotplug.h * @flags: PGMAP_* flags to specify defailed behavior * @ops: method table @@ -109,8 +98,7 @@ struct dev_pagemap_ops { */ struct dev_pagemap { struct vmem_altmap altmap; - struct percpu_ref *ref; - struct percpu_ref internal_ref; + struct percpu_ref ref; struct completion done; enum memory_type type; unsigned int flags; @@ -191,7 +179,7 @@ static inline unsigned long memremap_compat_align(void) static inline void put_dev_pagemap(struct dev_pagemap *pgmap) { if (pgmap) - percpu_ref_put(pgmap->ref); + percpu_ref_put(&pgmap->ref); } #endif /* _LINUX_MEMREMAP_H_ */ diff --git a/mm/memremap.c b/mm/memremap.c index 5a66a71ab591..643965da13a6 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -112,30 +112,6 @@ static unsigned long pfn_next(unsigned long pfn) #define for_each_device_pfn(pfn, map, i) \ for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn)) -static void dev_pagemap_kill(struct dev_pagemap *pgmap) -{ - if (pgmap->ops && pgmap->ops->kill) - pgmap->ops->kill(pgmap); - else - percpu_ref_kill(pgmap->ref); -} - -static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) -{ - if (pgmap->ops && pgmap->ops->cleanup) { - pgmap->ops->cleanup(pgmap); - } else { - wait_for_completion(&pgmap->done); - percpu_ref_exit(pgmap->ref); - } - /* - * Undo the pgmap ref assignment for the internal case as the - * caller may re-enable the same pgmap. - */ - if (pgmap->ref == &pgmap->internal_ref) - pgmap->ref = NULL; -} - static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) { struct range *range = &pgmap->ranges[range_id]; @@ -167,11 +143,12 @@ void memunmap_pages(struct dev_pagemap *pgmap) unsigned long pfn; int i; - dev_pagemap_kill(pgmap); + percpu_ref_kill(&pgmap->ref); for (i = 0; i < pgmap->nr_range; i++) for_each_device_pfn(pfn, pgmap, i) put_page(pfn_to_page(pfn)); - dev_pagemap_cleanup(pgmap); + wait_for_completion(&pgmap->done); + percpu_ref_exit(&pgmap->ref); for (i = 0; i < pgmap->nr_range; i++) pageunmap_range(pgmap, i); @@ -188,8 +165,7 @@ static void devm_memremap_pages_release(void *data) static void dev_pagemap_percpu_release(struct percpu_ref *ref) { - struct dev_pagemap *pgmap = - container_of(ref, struct dev_pagemap, internal_ref); + struct dev_pagemap *pgmap = container_of(ref, struct dev_pagemap, ref); complete(&pgmap->done); } @@ -295,8 +271,8 @@ static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params, memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], PHYS_PFN(range->start), PHYS_PFN(range_len(range)), pgmap); - percpu_ref_get_many(pgmap->ref, pfn_end(pgmap, range_id) - - pfn_first(pgmap, range_id)); + percpu_ref_get_many(&pgmap->ref, + pfn_end(pgmap, range_id) - pfn_first(pgmap, range_id)); return 0; err_add_memory: @@ -362,22 +338,11 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) break; } - if (!pgmap->ref) { - if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup)) - return ERR_PTR(-EINVAL); - - init_completion(&pgmap->done); - error = percpu_ref_init(&pgmap->internal_ref, - dev_pagemap_percpu_release, 0, GFP_KERNEL); - if (error) - return ERR_PTR(error); - pgmap->ref = &pgmap->internal_ref; - } else { - if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) { - WARN(1, "Missing reference count teardown definition\n"); - return ERR_PTR(-EINVAL); - } - } + init_completion(&pgmap->done); + error = percpu_ref_init(&pgmap->ref, dev_pagemap_percpu_release, 0, + GFP_KERNEL); + if (error) + return ERR_PTR(error); devmap_managed_enable_get(pgmap); @@ -486,7 +451,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, /* fall back to slow path lookup */ rcu_read_lock(); pgmap = xa_load(&pgmap_array, PHYS_PFN(phys)); - if (pgmap && !percpu_ref_tryget_live(pgmap->ref)) + if (pgmap && !percpu_ref_tryget_live(&pgmap->ref)) pgmap = NULL; rcu_read_unlock(); diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c index ed563bdd88f3..b752ce47ead3 100644 --- a/tools/testing/nvdimm/test/iomap.c +++ b/tools/testing/nvdimm/test/iomap.c @@ -100,25 +100,17 @@ static void nfit_test_kill(void *_pgmap) { struct dev_pagemap *pgmap = _pgmap; - WARN_ON(!pgmap || !pgmap->ref); + WARN_ON(!pgmap); - if (pgmap->ops && pgmap->ops->kill) - pgmap->ops->kill(pgmap); - else - percpu_ref_kill(pgmap->ref); + percpu_ref_kill(&pgmap->ref); - if (pgmap->ops && pgmap->ops->cleanup) { - pgmap->ops->cleanup(pgmap); - } else { - wait_for_completion(&pgmap->done); - percpu_ref_exit(pgmap->ref); - } + wait_for_completion(&pgmap->done); + percpu_ref_exit(&pgmap->ref); } static void dev_pagemap_percpu_release(struct percpu_ref *ref) { - struct dev_pagemap *pgmap = - container_of(ref, struct dev_pagemap, internal_ref); + struct dev_pagemap *pgmap = container_of(ref, struct dev_pagemap, ref); complete(&pgmap->done); } @@ -132,22 +124,11 @@ void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) if (!nfit_res) return devm_memremap_pages(dev, pgmap); - if (!pgmap->ref) { - if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup)) - return ERR_PTR(-EINVAL); - - init_completion(&pgmap->done); - error = percpu_ref_init(&pgmap->internal_ref, - dev_pagemap_percpu_release, 0, GFP_KERNEL); - if (error) - return ERR_PTR(error); - pgmap->ref = &pgmap->internal_ref; - } else { - if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) { - WARN(1, "Missing reference count teardown definition\n"); - return ERR_PTR(-EINVAL); - } - } + init_completion(&pgmap->done); + error = percpu_ref_init(&pgmap->ref, dev_pagemap_percpu_release, 0, + GFP_KERNEL); + if (error) + return ERR_PTR(error); error = devm_add_action_or_reset(dev, nfit_test_kill, pgmap); if (error)