diff --git a/drivers/dax/pmem.c b/drivers/dax/pmem.c index 033f49b31fdc..cb0d742fa23f 100644 --- a/drivers/dax/pmem.c +++ b/drivers/dax/pmem.c @@ -43,6 +43,7 @@ static void dax_pmem_percpu_exit(void *data) struct dax_pmem *dax_pmem = to_dax_pmem(ref); dev_dbg(dax_pmem->dev, "%s\n", __func__); + wait_for_completion(&dax_pmem->cmp); percpu_ref_exit(ref); } @@ -53,7 +54,6 @@ static void dax_pmem_percpu_kill(void *data) dev_dbg(dax_pmem->dev, "%s\n", __func__); percpu_ref_kill(ref); - wait_for_completion(&dax_pmem->cmp); } static int dax_pmem_probe(struct device *dev) diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 5b536be5a12e..fb7bbc79ac26 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -231,6 +232,11 @@ static void pmem_release_queue(void *q) blk_cleanup_queue(q); } +static void pmem_freeze_queue(void *q) +{ + blk_mq_freeze_queue_start(q); +} + static void pmem_release_disk(void *disk) { del_gendisk(disk); @@ -284,6 +290,9 @@ static int pmem_attach_disk(struct device *dev, if (!q) return -ENOMEM; + if (devm_add_action_or_reset(dev, pmem_release_queue, q)) + return -ENOMEM; + pmem->pfn_flags = PFN_DEV; if (is_nd_pfn(dev)) { addr = devm_memremap_pages(dev, &pfn_res, &q->q_usage_counter, @@ -303,10 +312,10 @@ static int pmem_attach_disk(struct device *dev, pmem->size, ARCH_MEMREMAP_PMEM); /* - * At release time the queue must be dead before + * At release time the queue must be frozen before * devm_memremap_pages is unwound */ - if (devm_add_action_or_reset(dev, pmem_release_queue, q)) + if (devm_add_action_or_reset(dev, pmem_freeze_queue, q)) return -ENOMEM; if (IS_ERR(addr)) diff --git a/include/linux/mm.h b/include/linux/mm.h index a835edd2db34..695da2a19b4c 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -762,19 +762,11 @@ static inline enum zone_type page_zonenum(const struct page *page) } #ifdef CONFIG_ZONE_DEVICE -void get_zone_device_page(struct page *page); -void put_zone_device_page(struct page *page); static inline bool is_zone_device_page(const struct page *page) { return page_zonenum(page) == ZONE_DEVICE; } #else -static inline void get_zone_device_page(struct page *page) -{ -} -static inline void put_zone_device_page(struct page *page) -{ -} static inline bool is_zone_device_page(const struct page *page) { return false; @@ -790,9 +782,6 @@ static inline void get_page(struct page *page) */ VM_BUG_ON_PAGE(page_ref_count(page) <= 0, page); page_ref_inc(page); - - if (unlikely(is_zone_device_page(page))) - get_zone_device_page(page); } static inline void put_page(struct page *page) @@ -801,9 +790,6 @@ static inline void put_page(struct page *page) if (put_page_testzero(page)) __put_page(page); - - if (unlikely(is_zone_device_page(page))) - put_zone_device_page(page); } #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP) diff --git a/kernel/memremap.c b/kernel/memremap.c index 07e85e5229da..23a6483c3666 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -182,18 +182,6 @@ struct page_map { struct vmem_altmap altmap; }; -void get_zone_device_page(struct page *page) -{ - percpu_ref_get(page->pgmap->ref); -} -EXPORT_SYMBOL(get_zone_device_page); - -void put_zone_device_page(struct page *page) -{ - put_dev_pagemap(page->pgmap); -} -EXPORT_SYMBOL(put_zone_device_page); - static void pgmap_radix_release(struct resource *res) { resource_size_t key, align_start, align_size, align_end; @@ -237,6 +225,10 @@ static void devm_memremap_pages_release(struct device *dev, void *data) struct resource *res = &page_map->res; resource_size_t align_start, align_size; struct dev_pagemap *pgmap = &page_map->pgmap; + unsigned long pfn; + + for_each_device_pfn(pfn, page_map) + put_page(pfn_to_page(pfn)); if (percpu_ref_tryget_live(pgmap->ref)) { dev_WARN(dev, "%s: page mapping is still live!\n", __func__); @@ -277,7 +269,10 @@ struct dev_pagemap *find_dev_pagemap(resource_size_t phys) * * Notes: * 1/ @ref must be 'live' on entry and 'dead' before devm_memunmap_pages() time - * (or devm release event). + * (or devm release event). The expected order of events is that @ref has + * been through percpu_ref_kill() before devm_memremap_pages_release(). The + * wait for the completion of all references being dropped and + * percpu_ref_exit() must occur after devm_memremap_pages_release(). * * 2/ @res is expected to be a host memory range that could feasibly be * treated as a "System RAM" range, i.e. not a device mmio range, but @@ -379,6 +374,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res, */ list_del(&page->lru); page->pgmap = pgmap; + percpu_ref_get(ref); } devres_add(dev, page_map); return __va(res->start); diff --git a/mm/swap.c b/mm/swap.c index c4910f14f957..a4e6113276b5 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -97,6 +97,16 @@ static void __put_compound_page(struct page *page) void __put_page(struct page *page) { + if (is_zone_device_page(page)) { + put_dev_pagemap(page->pgmap); + + /* + * The page belongs to the device that created pgmap. Do + * not return it to page allocator. + */ + return; + } + if (unlikely(PageCompound(page))) __put_compound_page(page); else