diff options
| -rw-r--r-- | drivers/dax/super.c | 14 | ||||
| -rw-r--r-- | drivers/nvdimm/pfn_devs.c | 2 | ||||
| -rw-r--r-- | drivers/nvdimm/pmem.c | 25 | ||||
| -rw-r--r-- | fs/Kconfig | 1 | ||||
| -rw-r--r-- | include/linux/memremap.h | 36 | ||||
| -rw-r--r-- | include/linux/mm.h | 71 | ||||
| -rw-r--r-- | kernel/memremap.c | 32 | ||||
| -rw-r--r-- | mm/Kconfig | 5 | ||||
| -rw-r--r-- | mm/hmm.c | 13 | ||||
| -rw-r--r-- | mm/swap.c | 3 |
10 files changed, 137 insertions, 65 deletions
diff --git a/drivers/dax/super.c b/drivers/dax/super.c index 2b2332b605e4..bf8bfaf5596f 100644 --- a/drivers/dax/super.c +++ b/drivers/dax/super.c @@ -86,6 +86,7 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize) { struct block_device *bdev = sb->s_bdev; struct dax_device *dax_dev; + bool dax_enabled = false; pgoff_t pgoff; int err, id; void *kaddr; @@ -134,14 +135,21 @@ int __bdev_dax_supported(struct super_block *sb, int blocksize) * on being able to do (page_address(pfn_to_page())). */ WARN_ON(IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API)); + dax_enabled = true; } else if (pfn_t_devmap(pfn)) { - /* pass */; - } else { + struct dev_pagemap *pgmap; + + pgmap = get_dev_pagemap(pfn_t_to_pfn(pfn), NULL); + if (pgmap && pgmap->type == MEMORY_DEVICE_FS_DAX) + dax_enabled = true; + put_dev_pagemap(pgmap); + } + + if (!dax_enabled) { pr_debug("VFS (%s): error: dax support not enabled\n", sb->s_id); return -EOPNOTSUPP; } - return 0; } EXPORT_SYMBOL_GPL(__bdev_dax_supported); diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 30b08791597d..3f7ad5bc443e 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -561,8 +561,6 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) res->start += start_pad; res->end -= end_trunc; - pgmap->type = MEMORY_DEVICE_HOST; - if (nd_pfn->mode == PFN_MODE_RAM) { if (offset < SZ_8K) return -EINVAL; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 9d714926ecf5..06b41ec9f1b3 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -294,6 +294,27 @@ static void pmem_release_disk(void *__pmem) put_disk(pmem->disk); } +static void pmem_release_pgmap_ops(void *__pgmap) +{ + dev_pagemap_put_ops(); +} + +static void fsdax_pagefree(struct page *page, void *data) +{ + wake_up_var(&page->_refcount); +} + +static int setup_pagemap_fsdax(struct device *dev, struct dev_pagemap *pgmap) +{ + dev_pagemap_get_ops(); + if (devm_add_action_or_reset(dev, pmem_release_pgmap_ops, pgmap)) + return -ENOMEM; + pgmap->type = MEMORY_DEVICE_FS_DAX; + pgmap->page_free = fsdax_pagefree; + + return 0; +} + static int pmem_attach_disk(struct device *dev, struct nd_namespace_common *ndns) { @@ -353,6 +374,8 @@ static int pmem_attach_disk(struct device *dev, pmem->pfn_flags = PFN_DEV; pmem->pgmap.ref = &q->q_usage_counter; if (is_nd_pfn(dev)) { + if (setup_pagemap_fsdax(dev, &pmem->pgmap)) + return -ENOMEM; addr = devm_memremap_pages(dev, &pmem->pgmap); pfn_sb = nd_pfn->pfn_sb; pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); @@ -364,6 +387,8 @@ static int pmem_attach_disk(struct device *dev, } else if (pmem_should_map_pages(dev)) { memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res)); pmem->pgmap.altmap_valid = false; + if (setup_pagemap_fsdax(dev, &pmem->pgmap)) + return -ENOMEM; addr = devm_memremap_pages(dev, &pmem->pgmap); pmem->pfn_flags |= PFN_MAP; memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res)); diff --git a/fs/Kconfig b/fs/Kconfig index bc821a86d965..1e050e012eb9 100644 --- a/fs/Kconfig +++ b/fs/Kconfig @@ -38,6 +38,7 @@ config FS_DAX bool "Direct Access (DAX) support" depends on MMU depends on !(ARM || MIPS || SPARC) + select DEV_PAGEMAP_OPS if (ZONE_DEVICE && !FS_DAX_LIMITED) select FS_IOMAP select DAX help diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 7b4899c06f49..5ebfff65da4d 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -1,7 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_MEMREMAP_H_ #define _LINUX_MEMREMAP_H_ -#include <linux/mm.h> #include <linux/ioport.h> #include <linux/percpu-refcount.h> @@ -30,13 +29,6 @@ struct vmem_altmap { * Specialize ZONE_DEVICE memory into multiple types each having differents * usage. * - * MEMORY_DEVICE_HOST: - * Persistent device memory (pmem): struct page might be allocated in different - * memory and architecture might want to perform special actions. It is similar - * to regular memory, in that the CPU can access it transparently. However, - * it is likely to have different bandwidth and latency than regular memory. - * See Documentation/nvdimm/nvdimm.txt for more information. - * * MEMORY_DEVICE_PRIVATE: * Device memory that is not directly addressable by the CPU: CPU can neither * read nor write private memory. In this case, we do still have struct pages @@ -53,11 +45,19 @@ struct vmem_altmap { * driver can hotplug the device memory using ZONE_DEVICE and with that memory * type. Any page of a process can be migrated to such memory. However no one * should be allow to pin such memory so that it can always be evicted. + * + * MEMORY_DEVICE_FS_DAX: + * Host memory that has similar access semantics as System RAM i.e. DMA + * coherent and supports page pinning. In support of coordinating page + * pinning vs other operations MEMORY_DEVICE_FS_DAX arranges for a + * wakeup event whenever a page is unpinned and becomes idle. This + * wakeup is used to coordinate physical address space management (ex: + * fs truncate/hole punch) vs pinned pages (ex: device dma). */ enum memory_type { - MEMORY_DEVICE_HOST = 0, - MEMORY_DEVICE_PRIVATE, + MEMORY_DEVICE_PRIVATE = 1, MEMORY_DEVICE_PUBLIC, + MEMORY_DEVICE_FS_DAX, }; /* @@ -129,8 +129,6 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, unsigned long vmem_altmap_offset(struct vmem_altmap *altmap); void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns); - -static inline bool is_zone_device_page(const struct page *page); #else static inline void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) @@ -161,20 +159,6 @@ static inline void vmem_altmap_free(struct vmem_altmap *altmap, } #endif /* CONFIG_ZONE_DEVICE */ -#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC) -static inline bool is_device_private_page(const struct page *page) -{ - return is_zone_device_page(page) && - page->pgmap->type == MEMORY_DEVICE_PRIVATE; -} - -static inline bool is_device_public_page(const struct page *page) -{ - return is_zone_device_page(page) && - page->pgmap->type == MEMORY_DEVICE_PUBLIC; -} -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ - static inline void put_dev_pagemap(struct dev_pagemap *pgmap) { if (pgmap) diff --git a/include/linux/mm.h b/include/linux/mm.h index 1ac1f06a4be6..6e19265ee8f8 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -821,27 +821,65 @@ static inline bool is_zone_device_page(const struct page *page) } #endif -#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC) -void put_zone_device_private_or_public_page(struct page *page); -DECLARE_STATIC_KEY_FALSE(device_private_key); -#define IS_HMM_ENABLED static_branch_unlikely(&device_private_key) -static inline bool is_device_private_page(const struct page *page); -static inline bool is_device_public_page(const struct page *page); -#else /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ -static inline void put_zone_device_private_or_public_page(struct page *page) +#ifdef CONFIG_DEV_PAGEMAP_OPS +void dev_pagemap_get_ops(void); +void dev_pagemap_put_ops(void); +void __put_devmap_managed_page(struct page *page); +DECLARE_STATIC_KEY_FALSE(devmap_managed_key); +static inline bool put_devmap_managed_page(struct page *page) +{ + if (!static_branch_unlikely(&devmap_managed_key)) + return false; + if (!is_zone_device_page(page)) + return false; + switch (page->pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + case MEMORY_DEVICE_PUBLIC: + case MEMORY_DEVICE_FS_DAX: + __put_devmap_managed_page(page); + return true; + default: + break; + } + return false; +} + +static inline bool is_device_private_page(const struct page *page) { + return is_zone_device_page(page) && + page->pgmap->type == MEMORY_DEVICE_PRIVATE; } -#define IS_HMM_ENABLED 0 + +static inline bool is_device_public_page(const struct page *page) +{ + return is_zone_device_page(page) && + page->pgmap->type == MEMORY_DEVICE_PUBLIC; +} + +#else /* CONFIG_DEV_PAGEMAP_OPS */ +static inline void dev_pagemap_get_ops(void) +{ +} + +static inline void dev_pagemap_put_ops(void) +{ +} + +static inline bool put_devmap_managed_page(struct page *page) +{ + return false; +} + static inline bool is_device_private_page(const struct page *page) { return false; } + static inline bool is_device_public_page(const struct page *page) { return false; } -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ - +#endif /* CONFIG_DEV_PAGEMAP_OPS */ static inline void get_page(struct page *page) { @@ -859,16 +897,13 @@ static inline void put_page(struct page *page) page = compound_head(page); /* - * For private device pages we need to catch refcount transition from - * 2 to 1, when refcount reach one it means the private device page is - * free and we need to inform the device driver through callback. See + * For devmap managed pages we need to catch refcount transition from + * 2 to 1, when refcount reach one it means the page is free and we + * need to inform the device driver through callback. See * include/linux/memremap.h and HMM for details. */ - if (IS_HMM_ENABLED && unlikely(is_device_private_page(page) || - unlikely(is_device_public_page(page)))) { - put_zone_device_private_or_public_page(page); + if (put_devmap_managed_page(page)) return; - } if (put_page_testzero(page)) __put_page(page); diff --git a/kernel/memremap.c b/kernel/memremap.c index 37a9604133f6..5857267a4af5 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -9,6 +9,7 @@ #include <linux/memory_hotplug.h> #include <linux/swap.h> #include <linux/swapops.h> +#include <linux/wait_bit.h> static DEFINE_MUTEX(pgmap_lock); static RADIX_TREE(pgmap_radix, GFP_KERNEL); @@ -300,9 +301,32 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, return pgmap; } +EXPORT_SYMBOL_GPL(get_dev_pagemap); -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC) -void put_zone_device_private_or_public_page(struct page *page) +#ifdef CONFIG_DEV_PAGEMAP_OPS +DEFINE_STATIC_KEY_FALSE(devmap_managed_key); +EXPORT_SYMBOL_GPL(devmap_managed_key); +static atomic_t devmap_enable; + +/* + * Toggle the static key for ->page_free() callbacks when dev_pagemap + * pages go idle. + */ +void dev_pagemap_get_ops(void) +{ + if (atomic_inc_return(&devmap_enable) == 1) + static_branch_enable(&devmap_managed_key); +} +EXPORT_SYMBOL_GPL(dev_pagemap_get_ops); + +void dev_pagemap_put_ops(void) +{ + if (atomic_dec_and_test(&devmap_enable)) + static_branch_disable(&devmap_managed_key); +} +EXPORT_SYMBOL_GPL(dev_pagemap_put_ops); + +void __put_devmap_managed_page(struct page *page) { int count = page_ref_dec_return(page); @@ -322,5 +346,5 @@ void put_zone_device_private_or_public_page(struct page *page) } else if (!count) __put_page(page); } -EXPORT_SYMBOL(put_zone_device_private_or_public_page); -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ +EXPORT_SYMBOL_GPL(__put_devmap_managed_page); +#endif /* CONFIG_DEV_PAGEMAP_OPS */ diff --git a/mm/Kconfig b/mm/Kconfig index d5004d82a1d6..bf9d6366bced 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -692,6 +692,9 @@ config ARCH_HAS_HMM config MIGRATE_VMA_HELPER bool +config DEV_PAGEMAP_OPS + bool + config HMM bool select MIGRATE_VMA_HELPER @@ -712,6 +715,7 @@ config DEVICE_PRIVATE bool "Unaddressable device memory (GPU memory, ...)" depends on ARCH_HAS_HMM select HMM + select DEV_PAGEMAP_OPS help Allows creation of struct pages to represent unaddressable device @@ -722,6 +726,7 @@ config DEVICE_PUBLIC bool "Addressable device memory (like GPU memory)" depends on ARCH_HAS_HMM select HMM + select DEV_PAGEMAP_OPS help Allows creation of struct pages to represent addressable device @@ -35,15 +35,6 @@ #define PA_SECTION_SIZE (1UL << PA_SECTION_SHIFT) -#if defined(CONFIG_DEVICE_PRIVATE) || defined(CONFIG_DEVICE_PUBLIC) -/* - * Device private memory see HMM (Documentation/vm/hmm.txt) or hmm.h - */ -DEFINE_STATIC_KEY_FALSE(device_private_key); -EXPORT_SYMBOL(device_private_key); -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ - - #if IS_ENABLED(CONFIG_HMM_MIRROR) static const struct mmu_notifier_ops hmm_mmu_notifier_ops; @@ -1167,7 +1158,7 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, resource_size_t addr; int ret; - static_branch_enable(&device_private_key); + dev_pagemap_get_ops(); devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem), GFP_KERNEL, dev_to_node(device)); @@ -1261,7 +1252,7 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY) return ERR_PTR(-EINVAL); - static_branch_enable(&device_private_key); + dev_pagemap_get_ops(); devmem = devres_alloc_node(&hmm_devmem_release, sizeof(*devmem), GFP_KERNEL, dev_to_node(device)); diff --git a/mm/swap.c b/mm/swap.c index 3dd518832096..26fc9b5f1b6c 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -29,6 +29,7 @@ #include <linux/cpu.h> #include <linux/notifier.h> #include <linux/backing-dev.h> +#include <linux/memremap.h> #include <linux/memcontrol.h> #include <linux/gfp.h> #include <linux/uio.h> @@ -743,7 +744,7 @@ void release_pages(struct page **pages, int nr) flags); locked_pgdat = NULL; } - put_zone_device_private_or_public_page(page); + put_devmap_managed_page(page); continue; } |