From 07ec38917e68f0114b9c8aeeb1c584b5e73e4dd6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:01 +0200 Subject: mm: remove the struct hmm_device infrastructure This code is a trivial wrapper around device model helpers, which should have been integrated into the driver device model usage from the start. Assuming it actually had users, which it never had since the code was added more than 1 1/2 years ago. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: John Hubbard Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- include/linux/hmm.h | 20 -------------------- 1 file changed, 20 deletions(-) (limited to 'include') diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 044a36d7c3f8..99765be3284d 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -751,26 +751,6 @@ static inline unsigned long hmm_devmem_page_get_drvdata(const struct page *page) { return page->hmm_data; } - - -/* - * struct hmm_device - fake device to hang device memory onto - * - * @device: device struct - * @minor: device minor number - */ -struct hmm_device { - struct device device; - unsigned int minor; -}; - -/* - * A device driver that wants to handle multiple devices memory through a - * single fake device can use hmm_device to do so. This is purely a helper and - * it is not strictly needed, in order to make use of any HMM functionality. - */ -struct hmm_device *hmm_device_new(void *drvdata); -void hmm_device_put(struct hmm_device *hmm_device); #endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ #else /* IS_ENABLED(CONFIG_HMM) */ static inline void hmm_mm_destroy(struct mm_struct *mm) {} -- cgit v1.2.3 From 25b2995a35b609119cf96f6b62eccd56c0234c7d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 13 Jun 2019 22:50:49 +0200 Subject: mm: remove MEMORY_DEVICE_PUBLIC support The code hasn't been used since it was added to the tree, and doesn't appear to actually be usable. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Acked-by: Michal Hocko Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- fs/proc/task_mmu.c | 2 +- include/linux/hmm.h | 7 ++----- include/linux/ioport.h | 1 - include/linux/memremap.h | 8 ------- include/linux/mm.h | 18 ++-------------- mm/Kconfig | 11 ---------- mm/gup.c | 7 ------- mm/hmm.c | 54 ++---------------------------------------------- mm/madvise.c | 2 +- mm/memcontrol.c | 13 ++++++------ mm/memory-failure.c | 6 +----- mm/memory.c | 40 +++-------------------------------- mm/migrate.c | 28 ++++--------------------- mm/swap.c | 11 ---------- 14 files changed, 22 insertions(+), 186 deletions(-) (limited to 'include') diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 01d4eb0e6bd1..74d8f00b3615 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1279,7 +1279,7 @@ static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, if (pm->show_pfn) frame = pte_pfn(pte); flags |= PM_PRESENT; - page = _vm_normal_page(vma, addr, pte, true); + page = vm_normal_page(vma, addr, pte); if (pte_soft_dirty(pte)) flags |= PM_SOFT_DIRTY; } else if (is_swap_pte(pte)) { diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 99765be3284d..44a5ac738bb5 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -584,7 +584,7 @@ static inline void hmm_mm_destroy(struct mm_struct *mm) {} static inline void hmm_mm_init(struct mm_struct *mm) {} #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC) +#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) struct hmm_devmem; struct page *hmm_vma_alloc_locked_page(struct vm_area_struct *vma, @@ -722,9 +722,6 @@ struct hmm_devmem { struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, struct device *device, unsigned long size); -struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, - struct device *device, - struct resource *res); /* * hmm_devmem_page_set_drvdata - set per-page driver data field @@ -751,7 +748,7 @@ static inline unsigned long hmm_devmem_page_get_drvdata(const struct page *page) { return page->hmm_data; } -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ +#endif /* CONFIG_DEVICE_PRIVATE */ #else /* IS_ENABLED(CONFIG_HMM) */ static inline void hmm_mm_destroy(struct mm_struct *mm) {} static inline void hmm_mm_init(struct mm_struct *mm) {} diff --git a/include/linux/ioport.h b/include/linux/ioport.h index da0ebaec25f0..dd961882bc74 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -132,7 +132,6 @@ enum { IORES_DESC_PERSISTENT_MEMORY = 4, IORES_DESC_PERSISTENT_MEMORY_LEGACY = 5, IORES_DESC_DEVICE_PRIVATE_MEMORY = 6, - IORES_DESC_DEVICE_PUBLIC_MEMORY = 7, }; /* helpers to define resources */ diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 1732dea030b2..995c62c5a48b 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -37,13 +37,6 @@ struct vmem_altmap { * A more complete discussion of unaddressable memory may be found in * include/linux/hmm.h and Documentation/vm/hmm.rst. * - * MEMORY_DEVICE_PUBLIC: - * Device memory that is cache coherent from device and CPU point of view. This - * is use on platform that have an advance system bus (like CAPI or CCIX). A - * 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 @@ -58,7 +51,6 @@ struct vmem_altmap { */ enum memory_type { MEMORY_DEVICE_PRIVATE = 1, - MEMORY_DEVICE_PUBLIC, MEMORY_DEVICE_FS_DAX, MEMORY_DEVICE_PCI_P2PDMA, }; diff --git a/include/linux/mm.h b/include/linux/mm.h index dd0b5f4e1e45..7399f9f08de6 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -944,7 +944,6 @@ static inline bool put_devmap_managed_page(struct 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; @@ -960,12 +959,6 @@ static inline bool is_device_private_page(const struct 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; -} - #ifdef CONFIG_PCI_P2PDMA static inline bool is_pci_p2pdma_page(const struct page *page) { @@ -998,11 +991,6 @@ 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; -} - static inline bool is_pci_p2pdma_page(const struct page *page) { return false; @@ -1431,10 +1419,8 @@ struct zap_details { pgoff_t last_index; /* Highest page->index to unmap */ }; -struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, - pte_t pte, bool with_public_device); -#define vm_normal_page(vma, addr, pte) _vm_normal_page(vma, addr, pte, false) - +struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, + pte_t pte); struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr, pmd_t pmd); diff --git a/mm/Kconfig b/mm/Kconfig index 0d2ba7e1f43e..6f35b85b3052 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -718,17 +718,6 @@ config DEVICE_PRIVATE memory; i.e., memory that is only accessible from the device (or group of devices). You likely also want to select HMM_MIRROR. -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 - memory; i.e., memory that is accessible from both the device and - the CPU - config FRAME_VECTOR bool diff --git a/mm/gup.c b/mm/gup.c index ddde097cf9e4..fe131d879c70 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -605,13 +605,6 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address, if ((gup_flags & FOLL_DUMP) || !is_zero_pfn(pte_pfn(*pte))) goto unmap; *page = pte_page(*pte); - - /* - * This should never happen (a device public page in the gate - * area). - */ - if (is_device_public_page(*page)) - goto unmap; } if (unlikely(!try_get_page(*page))) { ret = -ENOMEM; diff --git a/mm/hmm.c b/mm/hmm.c index 00cc642b3d7e..376159a769fb 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1331,7 +1331,7 @@ EXPORT_SYMBOL(hmm_range_dma_unmap); #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) || IS_ENABLED(CONFIG_DEVICE_PUBLIC) +#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) struct page *hmm_vma_alloc_locked_page(struct vm_area_struct *vma, unsigned long addr) { @@ -1478,54 +1478,4 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, return devmem; } EXPORT_SYMBOL_GPL(hmm_devmem_add); - -struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, - struct device *device, - struct resource *res) -{ - struct hmm_devmem *devmem; - void *result; - int ret; - - if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY) - return ERR_PTR(-EINVAL); - - dev_pagemap_get_ops(); - - devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL); - if (!devmem) - return ERR_PTR(-ENOMEM); - - init_completion(&devmem->completion); - devmem->pfn_first = -1UL; - devmem->pfn_last = -1UL; - devmem->resource = res; - devmem->device = device; - devmem->ops = ops; - - ret = percpu_ref_init(&devmem->ref, &hmm_devmem_ref_release, - 0, GFP_KERNEL); - if (ret) - return ERR_PTR(ret); - - devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; - devmem->pfn_last = devmem->pfn_first + - (resource_size(devmem->resource) >> PAGE_SHIFT); - devmem->page_fault = hmm_devmem_fault; - - devmem->pagemap.type = MEMORY_DEVICE_PUBLIC; - devmem->pagemap.res = *devmem->resource; - devmem->pagemap.page_free = hmm_devmem_free; - devmem->pagemap.altmap_valid = false; - devmem->pagemap.ref = &devmem->ref; - devmem->pagemap.data = devmem; - devmem->pagemap.kill = hmm_devmem_ref_kill; - devmem->pagemap.cleanup = hmm_devmem_ref_exit; - - result = devm_memremap_pages(devmem->device, &devmem->pagemap); - if (IS_ERR(result)) - return result; - return devmem; -} -EXPORT_SYMBOL_GPL(hmm_devmem_add_resource); -#endif /* CONFIG_DEVICE_PRIVATE || CONFIG_DEVICE_PUBLIC */ +#endif /* CONFIG_DEVICE_PRIVATE */ diff --git a/mm/madvise.c b/mm/madvise.c index 628022e674a7..968df3aa069f 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -354,7 +354,7 @@ static int madvise_free_pte_range(pmd_t *pmd, unsigned long addr, continue; } - page = _vm_normal_page(vma, addr, ptent, true); + page = vm_normal_page(vma, addr, ptent); if (!page) continue; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index ba9138a4a1de..d2a6454fa0bd 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4793,7 +4793,7 @@ enum mc_target_type { static struct page *mc_handle_present_pte(struct vm_area_struct *vma, unsigned long addr, pte_t ptent) { - struct page *page = _vm_normal_page(vma, addr, ptent, true); + struct page *page = vm_normal_page(vma, addr, ptent); if (!page || !page_mapped(page)) return NULL; @@ -4994,8 +4994,8 @@ out: * 2(MC_TARGET_SWAP): if the swap entry corresponding to this pte is a * target for charge migration. if @target is not NULL, the entry is stored * in target->ent. - * 3(MC_TARGET_DEVICE): like MC_TARGET_PAGE but page is MEMORY_DEVICE_PUBLIC - * or MEMORY_DEVICE_PRIVATE (so ZONE_DEVICE page and thus not on the lru). + * 3(MC_TARGET_DEVICE): like MC_TARGET_PAGE but page is MEMORY_DEVICE_PRIVATE + * (so ZONE_DEVICE page and thus not on the lru). * For now we such page is charge like a regular page would be as for all * intent and purposes it is just special memory taking the place of a * regular page. @@ -5029,8 +5029,7 @@ static enum mc_target_type get_mctgt_type(struct vm_area_struct *vma, */ if (page->mem_cgroup == mc.from) { ret = MC_TARGET_PAGE; - if (is_device_private_page(page) || - is_device_public_page(page)) + if (is_device_private_page(page)) ret = MC_TARGET_DEVICE; if (target) target->page = page; @@ -5101,8 +5100,8 @@ static int mem_cgroup_count_precharge_pte_range(pmd_t *pmd, if (ptl) { /* * Note their can not be MC_TARGET_DEVICE for now as we do not - * support transparent huge page with MEMORY_DEVICE_PUBLIC or - * MEMORY_DEVICE_PRIVATE but this might change. + * support transparent huge page with MEMORY_DEVICE_PRIVATE but + * this might change. */ if (get_mctgt_type_thp(vma, addr, *pmd, NULL) == MC_TARGET_PAGE) mc.precharge += HPAGE_PMD_NR; diff --git a/mm/memory-failure.c b/mm/memory-failure.c index d9cc6606f409..31e7c7b424a1 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1177,16 +1177,12 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags, goto unlock; } - switch (pgmap->type) { - case MEMORY_DEVICE_PRIVATE: - case MEMORY_DEVICE_PUBLIC: + if (pgmap->type == MEMORY_DEVICE_PRIVATE) { /* * TODO: Handle HMM pages which may need coordination * with device-side memory. */ goto unlock; - default: - break; } /* diff --git a/mm/memory.c b/mm/memory.c index ddf20bd0c317..2d14f4c7e152 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -571,8 +571,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, * PFNMAP mappings in order to support COWable mappings. * */ -struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, - pte_t pte, bool with_public_device) +struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, + pte_t pte) { unsigned long pfn = pte_pfn(pte); @@ -585,29 +585,6 @@ struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, return NULL; if (is_zero_pfn(pfn)) return NULL; - - /* - * Device public pages are special pages (they are ZONE_DEVICE - * pages but different from persistent memory). They behave - * allmost like normal pages. The difference is that they are - * not on the lru and thus should never be involve with any- - * thing that involve lru manipulation (mlock, numa balancing, - * ...). - * - * This is why we still want to return NULL for such page from - * vm_normal_page() so that we do not have to special case all - * call site of vm_normal_page(). - */ - if (likely(pfn <= highest_memmap_pfn)) { - struct page *page = pfn_to_page(pfn); - - if (is_device_public_page(page)) { - if (with_public_device) - return page; - return NULL; - } - } - if (pte_devmap(pte)) return NULL; @@ -797,17 +774,6 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, rss[mm_counter(page)]++; } else if (pte_devmap(pte)) { page = pte_page(pte); - - /* - * Cache coherent device memory behave like regular page and - * not like persistent memory page. For more informations see - * MEMORY_DEVICE_CACHE_COHERENT in memory_hotplug.h - */ - if (is_device_public_page(page)) { - get_page(page); - page_dup_rmap(page, false); - rss[mm_counter(page)]++; - } } out_set_pte: @@ -1063,7 +1029,7 @@ again: if (pte_present(ptent)) { struct page *page; - page = _vm_normal_page(vma, addr, ptent, true); + page = vm_normal_page(vma, addr, ptent); if (unlikely(details) && page) { /* * unmap_shared_mapping_pages() wants to diff --git a/mm/migrate.c b/mm/migrate.c index f2ecc2855a12..78d45e184457 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -246,8 +246,6 @@ static bool remove_migration_pte(struct page *page, struct vm_area_struct *vma, if (is_device_private_page(new)) { entry = make_device_private_entry(new, pte_write(pte)); pte = swp_entry_to_pte(entry); - } else if (is_device_public_page(new)) { - pte = pte_mkdevmap(pte); } } @@ -381,7 +379,6 @@ static int expected_page_refs(struct address_space *mapping, struct page *page) * ZONE_DEVICE pages. */ expected_count += is_device_private_page(page); - expected_count += is_device_public_page(page); if (mapping) expected_count += hpage_nr_pages(page) + page_has_private(page); @@ -994,10 +991,7 @@ static int move_to_new_page(struct page *newpage, struct page *page, if (!PageMappingFlags(page)) page->mapping = NULL; - if (unlikely(is_zone_device_page(newpage))) { - if (is_device_public_page(newpage)) - flush_dcache_page(newpage); - } else + if (likely(!is_zone_device_page(newpage))) flush_dcache_page(newpage); } @@ -2265,7 +2259,7 @@ again: pfn = 0; goto next; } - page = _vm_normal_page(migrate->vma, addr, pte, true); + page = vm_normal_page(migrate->vma, addr, pte); mpfn = migrate_pfn(pfn) | MIGRATE_PFN_MIGRATE; mpfn |= pte_write(pte) ? MIGRATE_PFN_WRITE : 0; } @@ -2406,16 +2400,7 @@ static bool migrate_vma_check_page(struct page *page) * FIXME proper solution is to rework migration_entry_wait() so * it does not need to take a reference on page. */ - if (is_device_private_page(page)) - return true; - - /* - * Only allow device public page to be migrated and account for - * the extra reference count imply by ZONE_DEVICE pages. - */ - if (!is_device_public_page(page)) - return false; - extra++; + return is_device_private_page(page); } /* For file back page */ @@ -2665,11 +2650,6 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, swp_entry = make_device_private_entry(page, vma->vm_flags & VM_WRITE); entry = swp_entry_to_pte(swp_entry); - } else if (is_device_public_page(page)) { - entry = pte_mkold(mk_pte(page, READ_ONCE(vma->vm_page_prot))); - if (vma->vm_flags & VM_WRITE) - entry = pte_mkwrite(pte_mkdirty(entry)); - entry = pte_mkdevmap(entry); } } else { entry = mk_pte(page, vma->vm_page_prot); @@ -2789,7 +2769,7 @@ static void migrate_vma_pages(struct migrate_vma *migrate) migrate->src[i] &= ~MIGRATE_PFN_MIGRATE; continue; } - } else if (!is_device_public_page(newpage)) { + } else { /* * Other types of ZONE_DEVICE page are not * supported. diff --git a/mm/swap.c b/mm/swap.c index 7ede3eddc12a..83107410d29f 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -740,17 +740,6 @@ void release_pages(struct page **pages, int nr) if (is_huge_zero_page(page)) continue; - /* Device public page can not be huge page */ - if (is_device_public_page(page)) { - if (locked_pgdat) { - spin_unlock_irqrestore(&locked_pgdat->lru_lock, - flags); - locked_pgdat = NULL; - } - put_devmap_managed_page(page); - continue; - } - page = compound_head(page); if (!put_page_testzero(page)) continue; -- cgit v1.2.3 From 0092908d16c604b8207c2141ec64b0fa4473bb03 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:06 +0200 Subject: mm: factor out a devm_request_free_mem_region helper Keep the physical address allocation that hmm_add_device does with the rest of the resource code, and allow future reuse of it without the hmm wrapper. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: John Hubbard Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- include/linux/ioport.h | 2 ++ kernel/resource.c | 39 +++++++++++++++++++++++++++++++++++++++ mm/hmm.c | 33 ++++----------------------------- 3 files changed, 45 insertions(+), 29 deletions(-) (limited to 'include') diff --git a/include/linux/ioport.h b/include/linux/ioport.h index dd961882bc74..a02b290ca08a 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -285,6 +285,8 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2) return (r1->start <= r2->end && r1->end >= r2->start); } +struct resource *devm_request_free_mem_region(struct device *dev, + struct resource *base, unsigned long size); #endif /* __ASSEMBLY__ */ #endif /* _LINUX_IOPORT_H */ diff --git a/kernel/resource.c b/kernel/resource.c index 158f04ec1d4f..d22423e85cf8 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -1628,6 +1628,45 @@ void resource_list_free(struct list_head *head) } EXPORT_SYMBOL(resource_list_free); +#ifdef CONFIG_DEVICE_PRIVATE +/** + * devm_request_free_mem_region - find free region for device private memory + * + * @dev: device struct to bind the resource to + * @size: size in bytes of the device memory to add + * @base: resource tree to look in + * + * This function tries to find an empty range of physical address big enough to + * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE + * memory, which in turn allocates struct pages. + */ +struct resource *devm_request_free_mem_region(struct device *dev, + struct resource *base, unsigned long size) +{ + resource_size_t end, addr; + struct resource *res; + + size = ALIGN(size, 1UL << PA_SECTION_SHIFT); + end = min_t(unsigned long, base->end, (1UL << MAX_PHYSMEM_BITS) - 1); + addr = end - size + 1UL; + + for (; addr > size && addr >= base->start; addr -= size) { + if (region_intersects(addr, size, 0, IORES_DESC_NONE) != + REGION_DISJOINT) + continue; + + res = devm_request_mem_region(dev, addr, size, dev_name(dev)); + if (!res) + return ERR_PTR(-ENOMEM); + res->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY; + return res; + } + + return ERR_PTR(-ERANGE); +} +EXPORT_SYMBOL_GPL(devm_request_free_mem_region); +#endif /* CONFIG_DEVICE_PRIVATE */ + static int __init strict_iomem(char *str) { if (strstr(str, "relaxed")) diff --git a/mm/hmm.c b/mm/hmm.c index e7dd2ab8f9ab..48574f8485bb 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -25,8 +25,6 @@ #include #include -#define PA_SECTION_SIZE (1UL << PA_SECTION_SHIFT) - #if IS_ENABLED(CONFIG_HMM_MIRROR) static const struct mmu_notifier_ops hmm_mmu_notifier_ops; @@ -1408,7 +1406,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, unsigned long size) { struct hmm_devmem *devmem; - resource_size_t addr; void *result; int ret; @@ -1430,32 +1427,10 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, if (ret) return ERR_PTR(ret); - size = ALIGN(size, PA_SECTION_SIZE); - addr = min((unsigned long)iomem_resource.end, - (1UL << MAX_PHYSMEM_BITS) - 1); - addr = addr - size + 1UL; - - /* - * FIXME add a new helper to quickly walk resource tree and find free - * range - * - * FIXME what about ioport_resource resource ? - */ - for (; addr > size && addr >= iomem_resource.start; addr -= size) { - ret = region_intersects(addr, size, 0, IORES_DESC_NONE); - if (ret != REGION_DISJOINT) - continue; - - devmem->resource = devm_request_mem_region(device, addr, size, - dev_name(device)); - if (!devmem->resource) - return ERR_PTR(-ENOMEM); - break; - } - if (!devmem->resource) - return ERR_PTR(-ERANGE); - - devmem->resource->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY; + devmem->resource = devm_request_free_mem_region(device, &iomem_resource, + size); + if (IS_ERR(devmem->resource)) + return ERR_CAST(devmem->resource); devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; devmem->pfn_last = devmem->pfn_first + (resource_size(devmem->resource) >> PAGE_SHIFT); -- cgit v1.2.3 From 3ed2dcdf54d5bf1f9823b5faf1a702e7cee53982 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:07 +0200 Subject: memremap: validate the pagemap type passed to devm_memremap_pages Most pgmap types are only supported when certain config options are enabled. Check for a type that is valid for the current configuration before setting up the pagemap. For this the usage of the 0 type for device dax gets replaced with an explicit MEMORY_DEVICE_DEVDAX type. Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/dax/device.c | 1 + include/linux/memremap.h | 8 ++++++++ kernel/memremap.c | 22 ++++++++++++++++++++++ 3 files changed, 31 insertions(+) (limited to 'include') diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 8465d12fecba..79014baa782d 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -468,6 +468,7 @@ int dev_dax_probe(struct device *dev) dev_dax->pgmap.ref = &dev_dax->ref; dev_dax->pgmap.kill = dev_dax_percpu_kill; dev_dax->pgmap.cleanup = dev_dax_percpu_exit; + dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; addr = devm_memremap_pages(dev, &dev_dax->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 995c62c5a48b..0c86f2c5ac9c 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -45,13 +45,21 @@ struct vmem_altmap { * wakeup is used to coordinate physical address space management (ex: * fs truncate/hole punch) vs pinned pages (ex: device dma). * + * MEMORY_DEVICE_DEVDAX: + * Host memory that has similar access semantics as System RAM i.e. DMA + * coherent and supports page pinning. In contrast to + * MEMORY_DEVICE_FS_DAX, this memory is access via a device-dax + * character device. + * * MEMORY_DEVICE_PCI_P2PDMA: * Device memory residing in a PCI BAR intended for use with Peer-to-Peer * transactions. */ enum memory_type { + /* 0 is reserved to catch uninitialized type fields */ MEMORY_DEVICE_PRIVATE = 1, MEMORY_DEVICE_FS_DAX, + MEMORY_DEVICE_DEVDAX, MEMORY_DEVICE_PCI_P2PDMA, }; diff --git a/kernel/memremap.c b/kernel/memremap.c index 6e1970719dc2..abda62d1e5a3 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -157,6 +157,28 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) pgprot_t pgprot = PAGE_KERNEL; int error, nid, is_ram; + switch (pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { + WARN(1, "Device private memory not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_FS_DAX: + if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || + IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { + WARN(1, "File system DAX not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_DEVDAX: + case MEMORY_DEVICE_PCI_P2PDMA: + break; + default: + WARN(1, "Invalid pgmap type %d\n", pgmap->type); + break; + } + if (!pgmap->ref || !pgmap->kill || !pgmap->cleanup) { WARN(1, "Missing reference count teardown definition\n"); return ERR_PTR(-EINVAL); -- cgit v1.2.3 From 1e240e8d4a7d92232b6214e02a0a4197a53afd6c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:08 +0200 Subject: memremap: move dev_pagemap callbacks into a separate structure The dev_pagemap is a growing too many callbacks. Move them into a separate ops structure so that they are not duplicated for multiple instances, and an attacker can't easily overwrite them. Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/dax/device.c | 11 +++++++---- drivers/dax/pmem/core.c | 2 +- drivers/nvdimm/pmem.c | 19 +++++++++++-------- drivers/pci/p2pdma.c | 8 ++++++-- include/linux/memremap.h | 36 ++++++++++++++++++++---------------- kernel/memremap.c | 18 +++++++++--------- mm/hmm.c | 10 +++++++--- tools/testing/nvdimm/test/iomap.c | 7 ++++--- 8 files changed, 65 insertions(+), 46 deletions(-) (limited to 'include') diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 79014baa782d..f390083a64d7 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -36,9 +36,8 @@ static void dev_dax_percpu_exit(struct percpu_ref *ref) percpu_ref_exit(ref); } -static void dev_dax_percpu_kill(struct percpu_ref *data) +static void dev_dax_percpu_kill(struct percpu_ref *ref) { - struct percpu_ref *ref = data; struct dev_dax *dev_dax = ref_to_dev_dax(ref); dev_dbg(&dev_dax->dev, "%s\n", __func__); @@ -442,6 +441,11 @@ static void dev_dax_kill(void *dev_dax) kill_dev_dax(dev_dax); } +static const struct dev_pagemap_ops dev_dax_pagemap_ops = { + .kill = dev_dax_percpu_kill, + .cleanup = dev_dax_percpu_exit, +}; + int dev_dax_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); @@ -466,9 +470,8 @@ int dev_dax_probe(struct device *dev) return rc; dev_dax->pgmap.ref = &dev_dax->ref; - dev_dax->pgmap.kill = dev_dax_percpu_kill; - dev_dax->pgmap.cleanup = dev_dax_percpu_exit; dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; + dev_dax->pgmap.ops = &dev_dax_pagemap_ops; addr = devm_memremap_pages(dev, &dev_dax->pgmap); if (IS_ERR(addr)) return PTR_ERR(addr); diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index f9f51786d556..6eb6dfdf19bf 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -16,7 +16,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) struct dev_dax *dev_dax; struct nd_namespace_io *nsio; struct dax_region *dax_region; - struct dev_pagemap pgmap = { 0 }; + struct dev_pagemap pgmap = { }; struct nd_namespace_common *ndns; struct nd_dax *nd_dax = to_nd_dax(dev); struct nd_pfn *nd_pfn = &nd_dax->nd_pfn; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 24d7fe7c74ed..c2449af2b388 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -303,7 +303,7 @@ static const struct attribute_group *pmem_attribute_groups[] = { NULL, }; -static void __pmem_release_queue(struct percpu_ref *ref) +static void pmem_pagemap_cleanup(struct percpu_ref *ref) { struct request_queue *q; @@ -313,10 +313,10 @@ static void __pmem_release_queue(struct percpu_ref *ref) static void pmem_release_queue(void *ref) { - __pmem_release_queue(ref); + pmem_pagemap_cleanup(ref); } -static void pmem_freeze_queue(struct percpu_ref *ref) +static void pmem_pagemap_kill(struct percpu_ref *ref) { struct request_queue *q; @@ -339,19 +339,24 @@ static void pmem_release_pgmap_ops(void *__pgmap) dev_pagemap_put_ops(); } -static void fsdax_pagefree(struct page *page, void *data) +static void pmem_pagemap_page_free(struct page *page, void *data) { wake_up_var(&page->_refcount); } +static const struct dev_pagemap_ops fsdax_pagemap_ops = { + .page_free = pmem_pagemap_page_free, + .kill = pmem_pagemap_kill, + .cleanup = pmem_pagemap_cleanup, +}; + 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; - + pgmap->ops = &fsdax_pagemap_ops; return 0; } @@ -409,8 +414,6 @@ static int pmem_attach_disk(struct device *dev, pmem->pfn_flags = PFN_DEV; pmem->pgmap.ref = &q->q_usage_counter; - pmem->pgmap.kill = pmem_freeze_queue; - pmem->pgmap.cleanup = __pmem_release_queue; if (is_nd_pfn(dev)) { if (setup_pagemap_fsdax(dev, &pmem->pgmap)) return -ENOMEM; diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index a4994aa3acc0..fb039259d463 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -153,6 +153,11 @@ out: 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 @@ -208,8 +213,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, 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; + pgmap->ops = &pci_p2pdma_pagemap_ops; addr = devm_memremap_pages(&pdev->dev, pgmap); if (IS_ERR(addr)) { diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 0c86f2c5ac9c..919755f48c7e 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -63,41 +63,45 @@ enum memory_type { MEMORY_DEVICE_PCI_P2PDMA, }; -/* - * Additional notes about MEMORY_DEVICE_PRIVATE may be found in - * include/linux/hmm.h and Documentation/vm/hmm.rst. There is also a brief - * explanation in include/linux/memory_hotplug.h. - * - * The page_free() callback is called once the page refcount reaches 1 - * (ZONE_DEVICE pages never reach 0 refcount unless there is a refcount bug. - * This allows the device driver to implement its own memory management.) - */ -typedef void (*dev_page_free_t)(struct page *page, void *data); +struct dev_pagemap_ops { + /* + * Called once the page refcount reaches 1. (ZONE_DEVICE pages never + * reach 0 refcount unless there is a refcount bug. This allows the + * device driver to implement its own memory management.) + */ + void (*page_free)(struct page *page, void *data); + + /* + * Transition the refcount in struct dev_pagemap to the dead state. + */ + void (*kill)(struct percpu_ref *ref); + + /* + * Wait for refcount in struct dev_pagemap to be idle and reap it. + */ + void (*cleanup)(struct percpu_ref *ref); +}; /** * struct dev_pagemap - metadata for ZONE_DEVICE mappings - * @page_free: free page callback when page refcount reaches 1 * @altmap: pre-allocated/reserved memory for vmemmap allocations * @res: physical address range covered by @ref * @ref: reference count that pins the devm_memremap_pages() mapping - * @kill: callback to transition @ref to the dead state - * @cleanup: callback to wait for @ref to be idle and reap it * @dev: host device of the mapping for debug * @data: private data pointer for page_free() * @type: memory type: see MEMORY_* in memory_hotplug.h + * @ops: method table */ struct dev_pagemap { - dev_page_free_t page_free; struct vmem_altmap altmap; bool altmap_valid; struct resource res; struct percpu_ref *ref; - void (*kill)(struct percpu_ref *ref); - void (*cleanup)(struct percpu_ref *ref); struct device *dev; void *data; enum memory_type type; u64 pci_p2pdma_bus_offset; + const struct dev_pagemap_ops *ops; }; #ifdef CONFIG_ZONE_DEVICE diff --git a/kernel/memremap.c b/kernel/memremap.c index abda62d1e5a3..0824237ef979 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -92,10 +92,10 @@ static void devm_memremap_pages_release(void *data) unsigned long pfn; int nid; - pgmap->kill(pgmap->ref); + pgmap->ops->kill(pgmap->ref); for_each_device_pfn(pfn, pgmap) put_page(pfn_to_page(pfn)); - pgmap->cleanup(pgmap->ref); + pgmap->ops->cleanup(pgmap->ref); /* pages are dead and unused, undo the arch mapping */ align_start = res->start & ~(SECTION_SIZE - 1); @@ -128,8 +128,8 @@ static void devm_memremap_pages_release(void *data) * @pgmap: pointer to a struct dev_pagemap * * Notes: - * 1/ At a minimum the res, ref and type members of @pgmap must be initialized - * by the caller before passing it to this function + * 1/ At a minimum the res, ref and type and ops members of @pgmap must be + * initialized by the caller before passing it to this function * * 2/ The altmap field may optionally be initialized, in which case altmap_valid * must be set to true @@ -179,7 +179,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) break; } - if (!pgmap->ref || !pgmap->kill || !pgmap->cleanup) { + if (!pgmap->ref || !pgmap->ops || !pgmap->ops->kill || + !pgmap->ops->cleanup) { WARN(1, "Missing reference count teardown definition\n"); return ERR_PTR(-EINVAL); } @@ -293,9 +294,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) err_pfn_remap: pgmap_array_delete(res); err_array: - pgmap->kill(pgmap->ref); - pgmap->cleanup(pgmap->ref); - + pgmap->ops->kill(pgmap->ref); + pgmap->ops->cleanup(pgmap->ref); return ERR_PTR(error); } EXPORT_SYMBOL_GPL(devm_memremap_pages); @@ -388,7 +388,7 @@ void __put_devmap_managed_page(struct page *page) mem_cgroup_uncharge(page); - page->pgmap->page_free(page, page->pgmap->data); + page->pgmap->ops->page_free(page, page->pgmap->data); } else if (!count) __put_page(page); } diff --git a/mm/hmm.c b/mm/hmm.c index 48574f8485bb..583a02a16872 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1384,6 +1384,12 @@ static void hmm_devmem_free(struct page *page, void *data) devmem->ops->free(devmem, page); } +static const struct dev_pagemap_ops hmm_pagemap_ops = { + .page_free = hmm_devmem_free, + .kill = hmm_devmem_ref_kill, + .cleanup = hmm_devmem_ref_exit, +}; + /* * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory * @@ -1438,12 +1444,10 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; devmem->pagemap.res = *devmem->resource; - devmem->pagemap.page_free = hmm_devmem_free; + devmem->pagemap.ops = &hmm_pagemap_ops; devmem->pagemap.altmap_valid = false; devmem->pagemap.ref = &devmem->ref; devmem->pagemap.data = devmem; - devmem->pagemap.kill = hmm_devmem_ref_kill; - devmem->pagemap.cleanup = hmm_devmem_ref_exit; result = devm_memremap_pages(devmem->device, &devmem->pagemap); if (IS_ERR(result)) diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c index 076df22e4bda..cf3f064a697d 100644 --- a/tools/testing/nvdimm/test/iomap.c +++ b/tools/testing/nvdimm/test/iomap.c @@ -100,9 +100,10 @@ static void nfit_test_kill(void *_pgmap) { struct dev_pagemap *pgmap = _pgmap; - WARN_ON(!pgmap || !pgmap->ref || !pgmap->kill || !pgmap->cleanup); - pgmap->kill(pgmap->ref); - pgmap->cleanup(pgmap->ref); + WARN_ON(!pgmap || !pgmap->ref || !pgmap->ops || !pgmap->ops->kill || + !pgmap->ops->cleanup); + pgmap->ops->kill(pgmap->ref); + pgmap->ops->cleanup(pgmap->ref); } void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) -- cgit v1.2.3 From d8668bb0451c3c45b59dbcde2654e0539aad1d2a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:09 +0200 Subject: memremap: pass a struct dev_pagemap to ->kill and ->cleanup Passing the actual typed structure leads to more understandable code vs just passing the ref member. Reported-by: Logan Gunthorpe Signed-off-by: Christoph Hellwig Reviewed-by: Logan Gunthorpe Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/dax/device.c | 12 ++++++------ drivers/nvdimm/pmem.c | 18 +++++++++--------- drivers/pci/p2pdma.c | 9 +++++---- include/linux/memremap.h | 4 ++-- kernel/memremap.c | 8 ++++---- mm/hmm.c | 10 +++++----- tools/testing/nvdimm/test/iomap.c | 4 ++-- 7 files changed, 33 insertions(+), 32 deletions(-) (limited to 'include') diff --git a/drivers/dax/device.c b/drivers/dax/device.c index f390083a64d7..b5257038c188 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -27,21 +27,21 @@ static void dev_dax_percpu_release(struct percpu_ref *ref) complete(&dev_dax->cmp); } -static void dev_dax_percpu_exit(struct percpu_ref *ref) +static void dev_dax_percpu_exit(struct dev_pagemap *pgmap) { - struct dev_dax *dev_dax = ref_to_dev_dax(ref); + struct dev_dax *dev_dax = container_of(pgmap, struct dev_dax, pgmap); dev_dbg(&dev_dax->dev, "%s\n", __func__); wait_for_completion(&dev_dax->cmp); - percpu_ref_exit(ref); + percpu_ref_exit(pgmap->ref); } -static void dev_dax_percpu_kill(struct percpu_ref *ref) +static void dev_dax_percpu_kill(struct dev_pagemap *pgmap) { - struct dev_dax *dev_dax = ref_to_dev_dax(ref); + struct dev_dax *dev_dax = container_of(pgmap, struct dev_dax, pgmap); dev_dbg(&dev_dax->dev, "%s\n", __func__); - percpu_ref_kill(ref); + percpu_ref_kill(pgmap->ref); } static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index c2449af2b388..9dac48359353 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -303,24 +303,24 @@ static const struct attribute_group *pmem_attribute_groups[] = { NULL, }; -static void pmem_pagemap_cleanup(struct percpu_ref *ref) +static void pmem_pagemap_cleanup(struct dev_pagemap *pgmap) { - struct request_queue *q; + struct request_queue *q = + container_of(pgmap->ref, struct request_queue, q_usage_counter); - q = container_of(ref, typeof(*q), q_usage_counter); blk_cleanup_queue(q); } -static void pmem_release_queue(void *ref) +static void pmem_release_queue(void *pgmap) { - pmem_pagemap_cleanup(ref); + pmem_pagemap_cleanup(pgmap); } -static void pmem_pagemap_kill(struct percpu_ref *ref) +static void pmem_pagemap_kill(struct dev_pagemap *pgmap) { - struct request_queue *q; + struct request_queue *q = + container_of(pgmap->ref, struct request_queue, q_usage_counter); - q = container_of(ref, typeof(*q), q_usage_counter); blk_freeze_queue_start(q); } @@ -435,7 +435,7 @@ static int pmem_attach_disk(struct device *dev, memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res)); } else { if (devm_add_action_or_reset(dev, pmem_release_queue, - &q->q_usage_counter)) + &pmem->pgmap)) return -ENOMEM; addr = devm_memremap(dev, pmem->phys_addr, pmem->size, ARCH_MEMREMAP_PMEM); diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index fb039259d463..fa6249e4ed5f 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -91,14 +91,15 @@ static void pci_p2pdma_percpu_release(struct percpu_ref *ref) complete(&p2p_pgmap->ref_done); } -static void pci_p2pdma_percpu_kill(struct percpu_ref *ref) +static void pci_p2pdma_percpu_kill(struct dev_pagemap *pgmap) { - percpu_ref_kill(ref); + percpu_ref_kill(pgmap->ref); } -static void pci_p2pdma_percpu_cleanup(struct percpu_ref *ref) +static void pci_p2pdma_percpu_cleanup(struct dev_pagemap *pgmap) { - struct p2pdma_pagemap *p2p_pgmap = to_p2p_pgmap(ref); + 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); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 919755f48c7e..b8666a0d8665 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -74,12 +74,12 @@ struct dev_pagemap_ops { /* * Transition the refcount in struct dev_pagemap to the dead state. */ - void (*kill)(struct percpu_ref *ref); + void (*kill)(struct dev_pagemap *pgmap); /* * Wait for refcount in struct dev_pagemap to be idle and reap it. */ - void (*cleanup)(struct percpu_ref *ref); + void (*cleanup)(struct dev_pagemap *pgmap); }; /** diff --git a/kernel/memremap.c b/kernel/memremap.c index 0824237ef979..00c1ceb60c19 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -92,10 +92,10 @@ static void devm_memremap_pages_release(void *data) unsigned long pfn; int nid; - pgmap->ops->kill(pgmap->ref); + pgmap->ops->kill(pgmap); for_each_device_pfn(pfn, pgmap) put_page(pfn_to_page(pfn)); - pgmap->ops->cleanup(pgmap->ref); + pgmap->ops->cleanup(pgmap); /* pages are dead and unused, undo the arch mapping */ align_start = res->start & ~(SECTION_SIZE - 1); @@ -294,8 +294,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) err_pfn_remap: pgmap_array_delete(res); err_array: - pgmap->ops->kill(pgmap->ref); - pgmap->ops->cleanup(pgmap->ref); + pgmap->ops->kill(pgmap); + pgmap->ops->cleanup(pgmap); return ERR_PTR(error); } EXPORT_SYMBOL_GPL(devm_memremap_pages); diff --git a/mm/hmm.c b/mm/hmm.c index 583a02a16872..987793fba923 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1352,18 +1352,18 @@ static void hmm_devmem_ref_release(struct percpu_ref *ref) complete(&devmem->completion); } -static void hmm_devmem_ref_exit(struct percpu_ref *ref) +static void hmm_devmem_ref_exit(struct dev_pagemap *pgmap) { struct hmm_devmem *devmem; - devmem = container_of(ref, struct hmm_devmem, ref); + devmem = container_of(pgmap, struct hmm_devmem, pagemap); wait_for_completion(&devmem->completion); - percpu_ref_exit(ref); + percpu_ref_exit(pgmap->ref); } -static void hmm_devmem_ref_kill(struct percpu_ref *ref) +static void hmm_devmem_ref_kill(struct dev_pagemap *pgmap) { - percpu_ref_kill(ref); + percpu_ref_kill(pgmap->ref); } static vm_fault_t hmm_devmem_fault(struct vm_area_struct *vma, diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c index cf3f064a697d..82f901569e06 100644 --- a/tools/testing/nvdimm/test/iomap.c +++ b/tools/testing/nvdimm/test/iomap.c @@ -102,8 +102,8 @@ static void nfit_test_kill(void *_pgmap) WARN_ON(!pgmap || !pgmap->ref || !pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup); - pgmap->ops->kill(pgmap->ref); - pgmap->ops->cleanup(pgmap->ref); + pgmap->ops->kill(pgmap); + pgmap->ops->cleanup(pgmap); } void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) -- cgit v1.2.3 From f6a55e1a3fe6b3bb294a80a05437fcf86488d819 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:10 +0200 Subject: memremap: lift the devmap_enable manipulation into devm_memremap_pages Just check if there is a ->page_free operation set and take care of the static key enable, as well as the put using device managed resources. Also check that a ->page_free is provided for the pgmaps types that require it, and check for a valid type as well while we are at it. Note that this also fixes the fact that hmm never called dev_pagemap_put_ops and thus would leave the slow path enabled forever, even after a device driver unload or disable. Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/nvdimm/pmem.c | 23 ++++---------------- include/linux/mm.h | 10 --------- kernel/memremap.c | 59 ++++++++++++++++++++++++++++++++------------------- mm/hmm.c | 2 -- 4 files changed, 41 insertions(+), 53 deletions(-) (limited to 'include') diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 9dac48359353..48767171a4df 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -334,11 +334,6 @@ 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 pmem_pagemap_page_free(struct page *page, void *data) { wake_up_var(&page->_refcount); @@ -350,16 +345,6 @@ static const struct dev_pagemap_ops fsdax_pagemap_ops = { .cleanup = pmem_pagemap_cleanup, }; -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->ops = &fsdax_pagemap_ops; - return 0; -} - static int pmem_attach_disk(struct device *dev, struct nd_namespace_common *ndns) { @@ -415,8 +400,8 @@ 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; + pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; + pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); pfn_sb = nd_pfn->pfn_sb; pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); @@ -428,8 +413,8 @@ 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; + pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; + pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); pmem->pfn_flags |= PFN_MAP; memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res)); diff --git a/include/linux/mm.h b/include/linux/mm.h index 7399f9f08de6..2425f4167ec2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -932,8 +932,6 @@ static inline bool is_zone_device_page(const struct page *page) #endif #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) @@ -973,14 +971,6 @@ static inline bool is_pci_p2pdma_page(const struct page *page) #endif /* CONFIG_PCI_P2PDMA */ #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; diff --git a/kernel/memremap.c b/kernel/memremap.c index 00c1ceb60c19..3219a4c91d07 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -17,6 +17,35 @@ static DEFINE_XARRAY(pgmap_array); #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1) #define SECTION_SIZE (1UL << PA_SECTION_SHIFT) +#ifdef CONFIG_DEV_PAGEMAP_OPS +DEFINE_STATIC_KEY_FALSE(devmap_managed_key); +EXPORT_SYMBOL(devmap_managed_key); +static atomic_t devmap_managed_enable; + +static void devmap_managed_enable_put(void *data) +{ + if (atomic_dec_and_test(&devmap_managed_enable)) + static_branch_disable(&devmap_managed_key); +} + +static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap) +{ + if (!pgmap->ops->page_free) { + WARN(1, "Missing page_free method\n"); + return -EINVAL; + } + + if (atomic_inc_return(&devmap_managed_enable) == 1) + static_branch_enable(&devmap_managed_key); + return devm_add_action_or_reset(dev, devmap_managed_enable_put, NULL); +} +#else +static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap) +{ + return -EINVAL; +} +#endif /* CONFIG_DEV_PAGEMAP_OPS */ + #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) vm_fault_t device_private_entry_fault(struct vm_area_struct *vma, unsigned long addr, @@ -156,6 +185,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) }; pgprot_t pgprot = PAGE_KERNEL; int error, nid, is_ram; + bool need_devmap_managed = true; switch (pgmap->type) { case MEMORY_DEVICE_PRIVATE: @@ -173,6 +203,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) break; case MEMORY_DEVICE_DEVDAX: case MEMORY_DEVICE_PCI_P2PDMA: + need_devmap_managed = false; break; default: WARN(1, "Invalid pgmap type %d\n", pgmap->type); @@ -185,6 +216,12 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) return ERR_PTR(-EINVAL); } + if (need_devmap_managed) { + error = devmap_managed_enable_get(dev, pgmap); + if (error) + return ERR_PTR(error); + } + align_start = res->start & ~(SECTION_SIZE - 1); align_size = ALIGN(res->start + resource_size(res), SECTION_SIZE) - align_start; @@ -351,28 +388,6 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, EXPORT_SYMBOL_GPL(get_dev_pagemap); #ifdef CONFIG_DEV_PAGEMAP_OPS -DEFINE_STATIC_KEY_FALSE(devmap_managed_key); -EXPORT_SYMBOL(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); diff --git a/mm/hmm.c b/mm/hmm.c index 987793fba923..5b0bd5f6a74f 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1415,8 +1415,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, void *result; int ret; - dev_pagemap_get_ops(); - devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL); if (!devmem) return ERR_PTR(-ENOMEM); -- cgit v1.2.3 From 897e6365cda6ba6356e83a3aaa68dec82ef4c548 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:11 +0200 Subject: memremap: add a migrate_to_ram method to struct dev_pagemap_ops This replaces the hacky ->fault callback, which is currently directly called from common code through a hmm specific data structure as an exercise in layering violations. Signed-off-by: Christoph Hellwig Reviewed-by: Ralph Campbell Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- include/linux/hmm.h | 6 ------ include/linux/memremap.h | 6 ++++++ include/linux/swapops.h | 15 --------------- kernel/memremap.c | 35 ++++------------------------------- mm/hmm.c | 13 +++++-------- mm/memory.c | 9 ++------- 6 files changed, 17 insertions(+), 67 deletions(-) (limited to 'include') diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 44a5ac738bb5..ba19c19e24ed 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -692,11 +692,6 @@ struct hmm_devmem_ops { * chunk, as an optimization. It must, however, prioritize the faulting address * over all the others. */ -typedef vm_fault_t (*dev_page_fault_t)(struct vm_area_struct *vma, - unsigned long addr, - const struct page *page, - unsigned int flags, - pmd_t *pmdp); struct hmm_devmem { struct completion completion; @@ -707,7 +702,6 @@ struct hmm_devmem { struct dev_pagemap pagemap; const struct hmm_devmem_ops *ops; struct percpu_ref ref; - dev_page_fault_t page_fault; }; /* diff --git a/include/linux/memremap.h b/include/linux/memremap.h index b8666a0d8665..ac985bd03a7f 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -80,6 +80,12 @@ struct dev_pagemap_ops { * 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. + */ + vm_fault_t (*migrate_to_ram)(struct vm_fault *vmf); }; /** diff --git a/include/linux/swapops.h b/include/linux/swapops.h index 4d961668e5fc..15bdb6fe71e5 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -129,12 +129,6 @@ static inline struct page *device_private_entry_to_page(swp_entry_t entry) { return pfn_to_page(swp_offset(entry)); } - -vm_fault_t device_private_entry_fault(struct vm_area_struct *vma, - unsigned long addr, - swp_entry_t entry, - unsigned int flags, - pmd_t *pmdp); #else /* CONFIG_DEVICE_PRIVATE */ static inline swp_entry_t make_device_private_entry(struct page *page, bool write) { @@ -164,15 +158,6 @@ static inline struct page *device_private_entry_to_page(swp_entry_t entry) { return NULL; } - -static inline vm_fault_t device_private_entry_fault(struct vm_area_struct *vma, - unsigned long addr, - swp_entry_t entry, - unsigned int flags, - pmd_t *pmdp) -{ - return VM_FAULT_SIGBUS; -} #endif /* CONFIG_DEVICE_PRIVATE */ #ifdef CONFIG_MIGRATION diff --git a/kernel/memremap.c b/kernel/memremap.c index 3219a4c91d07..c06a5487dda7 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -11,7 +11,6 @@ #include #include #include -#include static DEFINE_XARRAY(pgmap_array); #define SECTION_MASK ~((1UL << PA_SECTION_SHIFT) - 1) @@ -46,36 +45,6 @@ static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgm } #endif /* CONFIG_DEV_PAGEMAP_OPS */ -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) -vm_fault_t device_private_entry_fault(struct vm_area_struct *vma, - unsigned long addr, - swp_entry_t entry, - unsigned int flags, - pmd_t *pmdp) -{ - struct page *page = device_private_entry_to_page(entry); - struct hmm_devmem *devmem; - - devmem = container_of(page->pgmap, typeof(*devmem), pagemap); - - /* - * The page_fault() callback must migrate page back to system memory - * so that CPU can access it. This might fail for various reasons - * (device issue, device was unsafely unplugged, ...). When such - * error conditions happen, the callback must return VM_FAULT_SIGBUS. - * - * Note that because memory cgroup charges are accounted to the device - * memory, this should never fail because of memory restrictions (but - * allocation of regular system page might still fail because we are - * out of memory). - * - * There is a more in-depth description of what that callback can and - * cannot do, in include/linux/memremap.h - */ - return devmem->page_fault(vma, addr, page, flags, pmdp); -} -#endif /* CONFIG_DEVICE_PRIVATE */ - static void pgmap_array_delete(struct resource *res) { xa_store_range(&pgmap_array, PHYS_PFN(res->start), PHYS_PFN(res->end), @@ -193,6 +162,10 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) WARN(1, "Device private memory not supported\n"); return ERR_PTR(-EINVAL); } + if (!pgmap->ops || !pgmap->ops->migrate_to_ram) { + WARN(1, "Missing migrate_to_ram method\n"); + return ERR_PTR(-EINVAL); + } break; case MEMORY_DEVICE_FS_DAX: if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || diff --git a/mm/hmm.c b/mm/hmm.c index 5b0bd5f6a74f..96633ee066d8 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1366,15 +1366,12 @@ static void hmm_devmem_ref_kill(struct dev_pagemap *pgmap) percpu_ref_kill(pgmap->ref); } -static vm_fault_t hmm_devmem_fault(struct vm_area_struct *vma, - unsigned long addr, - const struct page *page, - unsigned int flags, - pmd_t *pmdp) +static vm_fault_t hmm_devmem_migrate_to_ram(struct vm_fault *vmf) { - struct hmm_devmem *devmem = page->pgmap->data; + struct hmm_devmem *devmem = vmf->page->pgmap->data; - return devmem->ops->fault(devmem, vma, addr, page, flags, pmdp); + return devmem->ops->fault(devmem, vmf->vma, vmf->address, vmf->page, + vmf->flags, vmf->pmd); } static void hmm_devmem_free(struct page *page, void *data) @@ -1388,6 +1385,7 @@ static const struct dev_pagemap_ops hmm_pagemap_ops = { .page_free = hmm_devmem_free, .kill = hmm_devmem_ref_kill, .cleanup = hmm_devmem_ref_exit, + .migrate_to_ram = hmm_devmem_migrate_to_ram, }; /* @@ -1438,7 +1436,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; devmem->pfn_last = devmem->pfn_first + (resource_size(devmem->resource) >> PAGE_SHIFT); - devmem->page_fault = hmm_devmem_fault; devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; devmem->pagemap.res = *devmem->resource; diff --git a/mm/memory.c b/mm/memory.c index 2d14f4c7e152..d437ccdb210c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2748,13 +2748,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) migration_entry_wait(vma->vm_mm, vmf->pmd, vmf->address); } else if (is_device_private_entry(entry)) { - /* - * For un-addressable device memory we call the pgmap - * fault handler callback. The callback must migrate - * the page back to some CPU accessible page. - */ - ret = device_private_entry_fault(vma, vmf->address, entry, - vmf->flags, vmf->pmd); + vmf->page = device_private_entry_to_page(entry); + ret = vmf->page->pgmap->ops->migrate_to_ram(vmf); } else if (is_hwpoison_entry(entry)) { ret = VM_FAULT_HWPOISON; } else { -- cgit v1.2.3 From 80a72d0af05ae97a8b106c172e431072ba587492 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:12 +0200 Subject: memremap: remove the data field in struct dev_pagemap struct dev_pagemap is always embedded into a containing structure, so there is no need to an additional private data field. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/nvdimm/pmem.c | 2 +- include/linux/memremap.h | 3 +-- kernel/memremap.c | 2 +- mm/hmm.c | 9 +++++---- 4 files changed, 8 insertions(+), 8 deletions(-) (limited to 'include') diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 48767171a4df..093408ce40ad 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -334,7 +334,7 @@ static void pmem_release_disk(void *__pmem) put_disk(pmem->disk); } -static void pmem_pagemap_page_free(struct page *page, void *data) +static void pmem_pagemap_page_free(struct page *page) { wake_up_var(&page->_refcount); } diff --git a/include/linux/memremap.h b/include/linux/memremap.h index ac985bd03a7f..336eca601dad 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -69,7 +69,7 @@ struct dev_pagemap_ops { * reach 0 refcount unless there is a refcount bug. This allows the * device driver to implement its own memory management.) */ - void (*page_free)(struct page *page, void *data); + void (*page_free)(struct page *page); /* * Transition the refcount in struct dev_pagemap to the dead state. @@ -104,7 +104,6 @@ struct dev_pagemap { struct resource res; struct percpu_ref *ref; struct device *dev; - void *data; enum memory_type type; u64 pci_p2pdma_bus_offset; const struct dev_pagemap_ops *ops; diff --git a/kernel/memremap.c b/kernel/memremap.c index c06a5487dda7..6c3dbb692037 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -376,7 +376,7 @@ void __put_devmap_managed_page(struct page *page) mem_cgroup_uncharge(page); - page->pgmap->ops->page_free(page, page->pgmap->data); + page->pgmap->ops->page_free(page); } else if (!count) __put_page(page); } diff --git a/mm/hmm.c b/mm/hmm.c index 96633ee066d8..36e25cdbdac1 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1368,15 +1368,17 @@ static void hmm_devmem_ref_kill(struct dev_pagemap *pgmap) static vm_fault_t hmm_devmem_migrate_to_ram(struct vm_fault *vmf) { - struct hmm_devmem *devmem = vmf->page->pgmap->data; + struct hmm_devmem *devmem = + container_of(vmf->page->pgmap, struct hmm_devmem, pagemap); return devmem->ops->fault(devmem, vmf->vma, vmf->address, vmf->page, vmf->flags, vmf->pmd); } -static void hmm_devmem_free(struct page *page, void *data) +static void hmm_devmem_free(struct page *page) { - struct hmm_devmem *devmem = data; + struct hmm_devmem *devmem = + container_of(page->pgmap, struct hmm_devmem, pagemap); devmem->ops->free(devmem, page); } @@ -1442,7 +1444,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->pagemap.ops = &hmm_pagemap_ops; devmem->pagemap.altmap_valid = false; devmem->pagemap.ref = &devmem->ref; - devmem->pagemap.data = devmem; result = devm_memremap_pages(devmem->device, &devmem->pagemap); if (IS_ERR(result)) -- cgit v1.2.3 From 514caf23a70fd697fa2ece238b2cd8dcc73fb16f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:13 +0200 Subject: memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag Add a flags field to struct dev_pagemap to replace the altmap_valid boolean to be a little more extensible. Also add a pgmap_altmap() helper to find the optional altmap and clean up the code using the altmap using it. Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- arch/powerpc/mm/mem.c | 10 +--------- arch/x86/mm/init_64.c | 8 ++------ drivers/nvdimm/pfn_devs.c | 3 +-- drivers/nvdimm/pmem.c | 1 - include/linux/memremap.h | 12 +++++++++++- kernel/memremap.c | 26 ++++++++++---------------- mm/hmm.c | 1 - mm/memory_hotplug.c | 6 ++---- mm/page_alloc.c | 5 ++--- 9 files changed, 29 insertions(+), 43 deletions(-) (limited to 'include') diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 2540d3b2588c..a2923c5c1982 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -131,17 +131,9 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size, { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; - struct page *page; + struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap); int ret; - /* - * If we have an altmap then we need to skip over any reserved PFNs - * when querying the zone. - */ - page = pfn_to_page(start_pfn); - if (altmap) - page += vmem_altmap_offset(altmap); - __remove_pages(page_zone(page), start_pfn, nr_pages, altmap); /* Remove htab bolted mappings for this section of memory */ diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 0f01c7b1d217..08bbf648827b 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1213,13 +1213,9 @@ void __ref arch_remove_memory(int nid, u64 start, u64 size, { unsigned long start_pfn = start >> PAGE_SHIFT; unsigned long nr_pages = size >> PAGE_SHIFT; - struct page *page = pfn_to_page(start_pfn); - struct zone *zone; + struct page *page = pfn_to_page(start_pfn) + vmem_altmap_offset(altmap); + struct zone *zone = page_zone(page); - /* With altmap the first mapped page is offset from @start */ - if (altmap) - page += vmem_altmap_offset(altmap); - zone = page_zone(page); __remove_pages(zone, start_pfn, nr_pages, altmap); kernel_physical_mapping_remove(start, start + size); } diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 0f81fc56bbfd..55fb6b7433ed 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -622,7 +622,6 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) if (offset < reserve) return -EINVAL; nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); - pgmap->altmap_valid = false; } else if (nd_pfn->mode == PFN_MODE_PMEM) { nd_pfn->npfns = PFN_SECTION_ALIGN_UP((resource_size(res) - offset) / PAGE_SIZE); @@ -634,7 +633,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) memcpy(altmap, &__altmap, sizeof(*altmap)); altmap->free = PHYS_PFN(offset - reserve); altmap->alloc = 0; - pgmap->altmap_valid = true; + pgmap->flags |= PGMAP_ALTMAP_VALID; } else return -ENXIO; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 093408ce40ad..e7d8cc9f41e8 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -412,7 +412,6 @@ static int pmem_attach_disk(struct device *dev, bb_res.start += pmem->data_offset; } else if (pmem_should_map_pages(dev)) { memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res)); - pmem->pgmap.altmap_valid = false; pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 336eca601dad..e25685b878e9 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -88,6 +88,8 @@ struct dev_pagemap_ops { vm_fault_t (*migrate_to_ram)(struct vm_fault *vmf); }; +#define PGMAP_ALTMAP_VALID (1 << 0) + /** * struct dev_pagemap - metadata for ZONE_DEVICE mappings * @altmap: pre-allocated/reserved memory for vmemmap allocations @@ -96,19 +98,27 @@ struct dev_pagemap_ops { * @dev: host device of the mapping for debug * @data: private data pointer for page_free() * @type: memory type: see MEMORY_* in memory_hotplug.h + * @flags: PGMAP_* flags to specify defailed behavior * @ops: method table */ struct dev_pagemap { struct vmem_altmap altmap; - bool altmap_valid; struct resource res; struct percpu_ref *ref; struct device *dev; enum memory_type type; + unsigned int flags; u64 pci_p2pdma_bus_offset; const struct dev_pagemap_ops *ops; }; +static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap) +{ + if (pgmap->flags & PGMAP_ALTMAP_VALID) + return &pgmap->altmap; + return NULL; +} + #ifdef CONFIG_ZONE_DEVICE void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap); void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap); diff --git a/kernel/memremap.c b/kernel/memremap.c index 6c3dbb692037..eee490e7d7e1 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -54,14 +54,8 @@ static void pgmap_array_delete(struct resource *res) static unsigned long pfn_first(struct dev_pagemap *pgmap) { - const struct resource *res = &pgmap->res; - struct vmem_altmap *altmap = &pgmap->altmap; - unsigned long pfn; - - pfn = res->start >> PAGE_SHIFT; - if (pgmap->altmap_valid) - pfn += vmem_altmap_offset(altmap); - return pfn; + return (pgmap->res.start >> PAGE_SHIFT) + + vmem_altmap_offset(pgmap_altmap(pgmap)); } static unsigned long pfn_end(struct dev_pagemap *pgmap) @@ -109,7 +103,7 @@ static void devm_memremap_pages_release(void *data) align_size >> PAGE_SHIFT, NULL); } else { arch_remove_memory(nid, align_start, align_size, - pgmap->altmap_valid ? &pgmap->altmap : NULL); + pgmap_altmap(pgmap)); kasan_remove_zero_shadow(__va(align_start), align_size); } mem_hotplug_done(); @@ -129,8 +123,8 @@ static void devm_memremap_pages_release(void *data) * 1/ At a minimum the res, ref and type and ops members of @pgmap must be * initialized by the caller before passing it to this function * - * 2/ The altmap field may optionally be initialized, in which case altmap_valid - * must be set to true + * 2/ The altmap field may optionally be initialized, in which case + * PGMAP_ALTMAP_VALID must be set in pgmap->flags. * * 3/ pgmap->ref must be 'live' on entry and will be killed and reaped * at devm_memremap_pages_release() time, or if this routine fails. @@ -142,15 +136,13 @@ static void devm_memremap_pages_release(void *data) void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) { resource_size_t align_start, align_size, align_end; - struct vmem_altmap *altmap = pgmap->altmap_valid ? - &pgmap->altmap : NULL; struct resource *res = &pgmap->res; struct dev_pagemap *conflict_pgmap; struct mhp_restrictions restrictions = { /* * We do not want any optional features only our own memmap */ - .altmap = altmap, + .altmap = pgmap_altmap(pgmap), }; pgprot_t pgprot = PAGE_KERNEL; int error, nid, is_ram; @@ -274,7 +266,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE]; move_pfn_range_to_zone(zone, align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, altmap); + align_size >> PAGE_SHIFT, pgmap_altmap(pgmap)); } mem_hotplug_done(); @@ -319,7 +311,9 @@ EXPORT_SYMBOL_GPL(devm_memunmap_pages); unsigned long vmem_altmap_offset(struct vmem_altmap *altmap) { /* number of pfns from base where pfn_to_page() is valid */ - return altmap->reserve + altmap->free; + if (altmap) + return altmap->reserve + altmap->free; + return 0; } void vmem_altmap_free(struct vmem_altmap *altmap, unsigned long nr_pfns) diff --git a/mm/hmm.c b/mm/hmm.c index 36e25cdbdac1..e4470462298f 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1442,7 +1442,6 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; devmem->pagemap.res = *devmem->resource; devmem->pagemap.ops = &hmm_pagemap_ops; - devmem->pagemap.altmap_valid = false; devmem->pagemap.ref = &devmem->ref; result = devm_memremap_pages(devmem->device, &devmem->pagemap); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index e096c987d261..6166ba5a15f3 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -557,10 +557,8 @@ void __remove_pages(struct zone *zone, unsigned long phys_start_pfn, int sections_to_remove; /* In the ZONE_DEVICE case device driver owns the memory region */ - if (is_dev_zone(zone)) { - if (altmap) - map_offset = vmem_altmap_offset(altmap); - } + if (is_dev_zone(zone)) + map_offset = vmem_altmap_offset(altmap); clear_zone_contiguous(zone); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d66bc8abe0af..17a39d40a556 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5853,6 +5853,7 @@ void __ref memmap_init_zone_device(struct zone *zone, { unsigned long pfn, end_pfn = start_pfn + size; struct pglist_data *pgdat = zone->zone_pgdat; + struct vmem_altmap *altmap = pgmap_altmap(pgmap); unsigned long zone_idx = zone_idx(zone); unsigned long start = jiffies; int nid = pgdat->node_id; @@ -5865,9 +5866,7 @@ void __ref memmap_init_zone_device(struct zone *zone, * of the pages reserved for the memmap, so we can just jump to * the end of that region and start processing the device pages. */ - if (pgmap->altmap_valid) { - struct vmem_altmap *altmap = &pgmap->altmap; - + if (altmap) { start_pfn = altmap->base_pfn + vmem_altmap_offset(altmap); size = end_pfn - start_pfn; } -- cgit v1.2.3 From 24917f6b1041a73993178920656e13364f847995 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:14 +0200 Subject: memremap: provide an optional internal refcount in struct dev_pagemap Provide an internal refcounting logic if no ->ref field is provided in the pagemap passed into devm_memremap_pages so that callers don't have to reinvent it poorly. Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny Reviewed-by: Dan Williams Tested-by: Dan Williams Signed-off-by: Jason Gunthorpe --- include/linux/memremap.h | 4 +++ kernel/memremap.c | 64 +++++++++++++++++++++++++++++++-------- tools/testing/nvdimm/test/iomap.c | 58 +++++++++++++++++++++++++++-------- 3 files changed, 101 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/linux/memremap.h b/include/linux/memremap.h index e25685b878e9..f8a5b2a19945 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -95,6 +95,8 @@ struct dev_pagemap_ops { * @altmap: pre-allocated/reserved memory for vmemmap allocations * @res: physical address range covered by @ref * @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 * @dev: host device of the mapping for debug * @data: private data pointer for page_free() * @type: memory type: see MEMORY_* in memory_hotplug.h @@ -105,6 +107,8 @@ struct dev_pagemap { struct vmem_altmap altmap; struct resource res; struct percpu_ref *ref; + struct percpu_ref internal_ref; + struct completion done; struct device *dev; enum memory_type type; unsigned int flags; diff --git a/kernel/memremap.c b/kernel/memremap.c index eee490e7d7e1..bea6f887adad 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -29,7 +29,7 @@ static void devmap_managed_enable_put(void *data) static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap) { - if (!pgmap->ops->page_free) { + if (!pgmap->ops || !pgmap->ops->page_free) { WARN(1, "Missing page_free method\n"); return -EINVAL; } @@ -75,6 +75,24 @@ static unsigned long pfn_next(unsigned long pfn) #define for_each_device_pfn(pfn, map) \ for (pfn = pfn_first(map); pfn < pfn_end(map); 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); + } +} + static void devm_memremap_pages_release(void *data) { struct dev_pagemap *pgmap = data; @@ -84,10 +102,10 @@ static void devm_memremap_pages_release(void *data) unsigned long pfn; int nid; - pgmap->ops->kill(pgmap); + dev_pagemap_kill(pgmap); for_each_device_pfn(pfn, pgmap) put_page(pfn_to_page(pfn)); - pgmap->ops->cleanup(pgmap); + dev_pagemap_cleanup(pgmap); /* pages are dead and unused, undo the arch mapping */ align_start = res->start & ~(SECTION_SIZE - 1); @@ -114,20 +132,29 @@ static void devm_memremap_pages_release(void *data) "%s: failed to free all reserved pages\n", __func__); } +static void dev_pagemap_percpu_release(struct percpu_ref *ref) +{ + struct dev_pagemap *pgmap = + container_of(ref, struct dev_pagemap, internal_ref); + + complete(&pgmap->done); +} + /** * devm_memremap_pages - remap and provide memmap backing for the given resource * @dev: hosting device for @res * @pgmap: pointer to a struct dev_pagemap * * Notes: - * 1/ At a minimum the res, ref and type and ops members of @pgmap must be - * initialized by the caller before passing it to this function + * 1/ At a minimum the res and type members of @pgmap must be initialized + * by the caller before passing it to this function * * 2/ The altmap field may optionally be initialized, in which case * PGMAP_ALTMAP_VALID must be set in pgmap->flags. * - * 3/ pgmap->ref must be 'live' on entry and will be killed and reaped - * at devm_memremap_pages_release() time, or if this routine fails. + * 3/ The ref field may optionally be provided, in which pgmap->ref must be + * 'live' on entry and will be killed and reaped at + * devm_memremap_pages_release() time, or if this routine fails. * * 4/ 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 @@ -175,10 +202,21 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) break; } - if (!pgmap->ref || !pgmap->ops || !pgmap->ops->kill || - !pgmap->ops->cleanup) { - WARN(1, "Missing reference count teardown definition\n"); - return ERR_PTR(-EINVAL); + 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); + } } if (need_devmap_managed) { @@ -296,8 +334,8 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) err_pfn_remap: pgmap_array_delete(res); err_array: - pgmap->ops->kill(pgmap); - pgmap->ops->cleanup(pgmap); + dev_pagemap_kill(pgmap); + dev_pagemap_cleanup(pgmap); return ERR_PTR(error); } EXPORT_SYMBOL_GPL(devm_memremap_pages); diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c index 82f901569e06..cd040b5abffe 100644 --- a/tools/testing/nvdimm/test/iomap.c +++ b/tools/testing/nvdimm/test/iomap.c @@ -100,26 +100,60 @@ static void nfit_test_kill(void *_pgmap) { struct dev_pagemap *pgmap = _pgmap; - WARN_ON(!pgmap || !pgmap->ref || !pgmap->ops || !pgmap->ops->kill || - !pgmap->ops->cleanup); - pgmap->ops->kill(pgmap); - pgmap->ops->cleanup(pgmap); + WARN_ON(!pgmap || !pgmap->ref); + + if (pgmap->ops && pgmap->ops->kill) + pgmap->ops->kill(pgmap); + else + 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); + } +} + +static void dev_pagemap_percpu_release(struct percpu_ref *ref) +{ + struct dev_pagemap *pgmap = + container_of(ref, struct dev_pagemap, internal_ref); + + complete(&pgmap->done); } void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) { + int error; resource_size_t offset = pgmap->res.start; struct nfit_test_resource *nfit_res = get_nfit_res(offset); - if (nfit_res) { - int rc; - - rc = devm_add_action_or_reset(dev, nfit_test_kill, pgmap); - if (rc) - return ERR_PTR(rc); - return nfit_res->buf + offset - nfit_res->res.start; + if (!nfit_res) + return devm_memremap_pages(dev, pgmap); + + pgmap->dev = dev; + 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); + } } - return devm_memremap_pages(dev, pgmap); + + error = devm_add_action_or_reset(dev, nfit_test_kill, pgmap); + if (error) + return ERR_PTR(error); + return nfit_res->buf + offset - nfit_res->res.start; } EXPORT_SYMBOL_GPL(__wrap_devm_memremap_pages); -- cgit v1.2.3 From 47e9d836a5e827acdaa5cb6175648fbef15b4e84 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:19 +0200 Subject: mm: remove hmm_vma_alloc_locked_page The only user of it has just been removed, and there wasn't really any need to wrap a basic memory allocator to start with. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- include/linux/hmm.h | 3 --- mm/hmm.c | 14 -------------- 2 files changed, 17 deletions(-) (limited to 'include') diff --git a/include/linux/hmm.h b/include/linux/hmm.h index ba19c19e24ed..1d55b7ea2da6 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -587,9 +587,6 @@ static inline void hmm_mm_init(struct mm_struct *mm) {} #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) struct hmm_devmem; -struct page *hmm_vma_alloc_locked_page(struct vm_area_struct *vma, - unsigned long addr); - /* * struct hmm_devmem_ops - callback for ZONE_DEVICE memory events * diff --git a/mm/hmm.c b/mm/hmm.c index e4470462298f..fdbd48771292 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1330,20 +1330,6 @@ EXPORT_SYMBOL(hmm_range_dma_unmap); #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) -struct page *hmm_vma_alloc_locked_page(struct vm_area_struct *vma, - unsigned long addr) -{ - struct page *page; - - page = alloc_page_vma(GFP_HIGHUSER, vma, addr); - if (!page) - return NULL; - lock_page(page); - return page; -} -EXPORT_SYMBOL(hmm_vma_alloc_locked_page); - - static void hmm_devmem_ref_release(struct percpu_ref *ref) { struct hmm_devmem *devmem; -- cgit v1.2.3 From eee3ae41b153e55e25d6cf7bd5b5098ba0afe705 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:20 +0200 Subject: mm: remove hmm_devmem_add There isn't really much value add in the hmm_devmem_add wrapper and more, as using devm_memremap_pages directly now is just as simple. Signed-off-by: Christoph Hellwig Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- Documentation/vm/hmm.rst | 26 ---------- include/linux/hmm.h | 129 ----------------------------------------------- mm/hmm.c | 110 ---------------------------------------- 3 files changed, 265 deletions(-) (limited to 'include') diff --git a/Documentation/vm/hmm.rst b/Documentation/vm/hmm.rst index 7cdf7282e022..50e1380950a9 100644 --- a/Documentation/vm/hmm.rst +++ b/Documentation/vm/hmm.rst @@ -329,32 +329,6 @@ directly using struct page for device memory which left most kernel code paths unaware of the difference. We only need to make sure that no one ever tries to map those pages from the CPU side. -HMM provides a set of helpers to register and hotplug device memory as a new -region needing a struct page. This is offered through a very simple API:: - - struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, - struct device *device, - unsigned long size); - void hmm_devmem_remove(struct hmm_devmem *devmem); - -The hmm_devmem_ops is where most of the important things are:: - - struct hmm_devmem_ops { - void (*free)(struct hmm_devmem *devmem, struct page *page); - int (*fault)(struct hmm_devmem *devmem, - struct vm_area_struct *vma, - unsigned long addr, - struct page *page, - unsigned flags, - pmd_t *pmdp); - }; - -The first callback (free()) happens when the last reference on a device page is -dropped. This means the device page is now free and no longer used by anyone. -The second callback happens whenever the CPU tries to access a device page -which it cannot do. This second callback must trigger a migration back to -system memory. - Migration to and from device memory =================================== diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 1d55b7ea2da6..86aa4ec3404c 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -585,135 +585,6 @@ static inline void hmm_mm_init(struct mm_struct *mm) {} #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ #if IS_ENABLED(CONFIG_DEVICE_PRIVATE) -struct hmm_devmem; - -/* - * struct hmm_devmem_ops - callback for ZONE_DEVICE memory events - * - * @free: call when refcount on page reach 1 and thus is no longer use - * @fault: call when there is a page fault to unaddressable memory - * - * Both callback happens from page_free() and page_fault() callback of struct - * dev_pagemap respectively. See include/linux/memremap.h for more details on - * those. - * - * The hmm_devmem_ops callback are just here to provide a coherent and - * uniq API to device driver and device driver should not register their - * own page_free() or page_fault() but rely on the hmm_devmem_ops call- - * back. - */ -struct hmm_devmem_ops { - /* - * free() - free a device page - * @devmem: device memory structure (see struct hmm_devmem) - * @page: pointer to struct page being freed - * - * Call back occurs whenever a device page refcount reach 1 which - * means that no one is holding any reference on the page anymore - * (ZONE_DEVICE page have an elevated refcount of 1 as default so - * that they are not release to the general page allocator). - * - * Note that callback has exclusive ownership of the page (as no - * one is holding any reference). - */ - void (*free)(struct hmm_devmem *devmem, struct page *page); - /* - * fault() - CPU page fault or get user page (GUP) - * @devmem: device memory structure (see struct hmm_devmem) - * @vma: virtual memory area containing the virtual address - * @addr: virtual address that faulted or for which there is a GUP - * @page: pointer to struct page backing virtual address (unreliable) - * @flags: FAULT_FLAG_* (see include/linux/mm.h) - * @pmdp: page middle directory - * Returns: VM_FAULT_MINOR/MAJOR on success or one of VM_FAULT_ERROR - * on error - * - * The callback occurs whenever there is a CPU page fault or GUP on a - * virtual address. This means that the device driver must migrate the - * page back to regular memory (CPU accessible). - * - * The device driver is free to migrate more than one page from the - * fault() callback as an optimization. However if device decide to - * migrate more than one page it must always priotirize the faulting - * address over the others. - * - * The struct page pointer is only given as an hint to allow quick - * lookup of internal device driver data. A concurrent migration - * might have already free that page and the virtual address might - * not longer be back by it. So it should not be modified by the - * callback. - * - * Note that mmap semaphore is held in read mode at least when this - * callback occurs, hence the vma is valid upon callback entry. - */ - vm_fault_t (*fault)(struct hmm_devmem *devmem, - struct vm_area_struct *vma, - unsigned long addr, - const struct page *page, - unsigned int flags, - pmd_t *pmdp); -}; - -/* - * struct hmm_devmem - track device memory - * - * @completion: completion object for device memory - * @pfn_first: first pfn for this resource (set by hmm_devmem_add()) - * @pfn_last: last pfn for this resource (set by hmm_devmem_add()) - * @resource: IO resource reserved for this chunk of memory - * @pagemap: device page map for that chunk - * @device: device to bind resource to - * @ops: memory operations callback - * @ref: per CPU refcount - * @page_fault: callback when CPU fault on an unaddressable device page - * - * This an helper structure for device drivers that do not wish to implement - * the gory details related to hotplugging new memoy and allocating struct - * pages. - * - * Device drivers can directly use ZONE_DEVICE memory on their own if they - * wish to do so. - * - * The page_fault() callback must migrate page back, from device memory to - * system memory, so that the CPU can access it. This might fail for various - * reasons (device issues, device have been unplugged, ...). When such error - * conditions happen, the page_fault() callback must return VM_FAULT_SIGBUS and - * set the CPU page table entry to "poisoned". - * - * Note that because memory cgroup charges are transferred to the device memory, - * this should never fail due to memory restrictions. However, allocation - * of a regular system page might still fail because we are out of memory. If - * that happens, the page_fault() callback must return VM_FAULT_OOM. - * - * The page_fault() callback can also try to migrate back multiple pages in one - * chunk, as an optimization. It must, however, prioritize the faulting address - * over all the others. - */ - -struct hmm_devmem { - struct completion completion; - unsigned long pfn_first; - unsigned long pfn_last; - struct resource *resource; - struct device *device; - struct dev_pagemap pagemap; - const struct hmm_devmem_ops *ops; - struct percpu_ref ref; -}; - -/* - * To add (hotplug) device memory, HMM assumes that there is no real resource - * that reserves a range in the physical address space (this is intended to be - * use by unaddressable device memory). It will reserve a physical range big - * enough and allocate struct page for it. - * - * The device driver can wrap the hmm_devmem struct inside a private device - * driver struct. - */ -struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, - struct device *device, - unsigned long size); - /* * hmm_devmem_page_set_drvdata - set per-page driver data field * diff --git a/mm/hmm.c b/mm/hmm.c index fdbd48771292..90ca0cdab9db 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -1327,113 +1327,3 @@ long hmm_range_dma_unmap(struct hmm_range *range, } EXPORT_SYMBOL(hmm_range_dma_unmap); #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ - - -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) -static void hmm_devmem_ref_release(struct percpu_ref *ref) -{ - struct hmm_devmem *devmem; - - devmem = container_of(ref, struct hmm_devmem, ref); - complete(&devmem->completion); -} - -static void hmm_devmem_ref_exit(struct dev_pagemap *pgmap) -{ - struct hmm_devmem *devmem; - - devmem = container_of(pgmap, struct hmm_devmem, pagemap); - wait_for_completion(&devmem->completion); - percpu_ref_exit(pgmap->ref); -} - -static void hmm_devmem_ref_kill(struct dev_pagemap *pgmap) -{ - percpu_ref_kill(pgmap->ref); -} - -static vm_fault_t hmm_devmem_migrate_to_ram(struct vm_fault *vmf) -{ - struct hmm_devmem *devmem = - container_of(vmf->page->pgmap, struct hmm_devmem, pagemap); - - return devmem->ops->fault(devmem, vmf->vma, vmf->address, vmf->page, - vmf->flags, vmf->pmd); -} - -static void hmm_devmem_free(struct page *page) -{ - struct hmm_devmem *devmem = - container_of(page->pgmap, struct hmm_devmem, pagemap); - - devmem->ops->free(devmem, page); -} - -static const struct dev_pagemap_ops hmm_pagemap_ops = { - .page_free = hmm_devmem_free, - .kill = hmm_devmem_ref_kill, - .cleanup = hmm_devmem_ref_exit, - .migrate_to_ram = hmm_devmem_migrate_to_ram, -}; - -/* - * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory - * - * @ops: memory event device driver callback (see struct hmm_devmem_ops) - * @device: device struct to bind the resource too - * @size: size in bytes of the device memory to add - * Returns: pointer to new hmm_devmem struct ERR_PTR otherwise - * - * This function first finds an empty range of physical address big enough to - * contain the new resource, and then hotplugs it as ZONE_DEVICE memory, which - * in turn allocates struct pages. It does not do anything beyond that; all - * events affecting the memory will go through the various callbacks provided - * by hmm_devmem_ops struct. - * - * Device driver should call this function during device initialization and - * is then responsible of memory management. HMM only provides helpers. - */ -struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, - struct device *device, - unsigned long size) -{ - struct hmm_devmem *devmem; - void *result; - int ret; - - devmem = devm_kzalloc(device, sizeof(*devmem), GFP_KERNEL); - if (!devmem) - return ERR_PTR(-ENOMEM); - - init_completion(&devmem->completion); - devmem->pfn_first = -1UL; - devmem->pfn_last = -1UL; - devmem->resource = NULL; - devmem->device = device; - devmem->ops = ops; - - ret = percpu_ref_init(&devmem->ref, &hmm_devmem_ref_release, - 0, GFP_KERNEL); - if (ret) - return ERR_PTR(ret); - - devmem->resource = devm_request_free_mem_region(device, &iomem_resource, - size); - if (IS_ERR(devmem->resource)) - return ERR_CAST(devmem->resource); - devmem->pfn_first = devmem->resource->start >> PAGE_SHIFT; - devmem->pfn_last = devmem->pfn_first + - (resource_size(devmem->resource) >> PAGE_SHIFT); - - devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; - devmem->pagemap.res = *devmem->resource; - devmem->pagemap.ops = &hmm_pagemap_ops; - devmem->pagemap.ref = &devmem->ref; - - result = devm_memremap_pages(devmem->device, &devmem->pagemap); - if (IS_ERR(result)) - return result; - return devmem; -} -EXPORT_SYMBOL_GPL(hmm_devmem_add); -#endif /* CONFIG_DEVICE_PRIVATE */ -- cgit v1.2.3 From 8a164fef9c4ccf6ff7757170397222860e40d192 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:21 +0200 Subject: mm: simplify ZONE_DEVICE page private data Remove the clumsy hmm_devmem_page_{get,set}_drvdata helpers, and instead just access the page directly. Also make the page data a void pointer, and thus much easier to use. Signed-off-by: Christoph Hellwig Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/gpu/drm/nouveau/nouveau_dmem.c | 18 +++++++----------- include/linux/hmm.h | 32 -------------------------------- include/linux/mm_types.h | 2 +- mm/page_alloc.c | 8 ++++---- 4 files changed, 12 insertions(+), 48 deletions(-) (limited to 'include') diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c index 0fb7a44b8bc4..42c026010938 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dmem.c +++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c @@ -104,11 +104,8 @@ struct nouveau_migrate { static void nouveau_dmem_page_free(struct page *page) { - struct nouveau_dmem_chunk *chunk; - unsigned long idx; - - chunk = (void *)hmm_devmem_page_get_drvdata(page); - idx = page_to_pfn(page) - chunk->pfn_first; + struct nouveau_dmem_chunk *chunk = page->zone_device_data; + unsigned long idx = page_to_pfn(page) - chunk->pfn_first; /* * FIXME: @@ -200,7 +197,7 @@ nouveau_dmem_fault_alloc_and_copy(struct vm_area_struct *vma, dst_addr = fault->dma[fault->npages++]; - chunk = (void *)hmm_devmem_page_get_drvdata(spage); + chunk = spage->zone_device_data; src_addr = page_to_pfn(spage) - chunk->pfn_first; src_addr = (src_addr << PAGE_SHIFT) + chunk->bo->bo.offset; @@ -633,9 +630,8 @@ nouveau_dmem_init(struct nouveau_drm *drm) list_add_tail(&chunk->list, &drm->dmem->chunk_empty); page = pfn_to_page(chunk->pfn_first); - for (j = 0; j < DMEM_CHUNK_NPAGES; ++j, ++page) { - hmm_devmem_page_set_drvdata(page, (long)chunk); - } + for (j = 0; j < DMEM_CHUNK_NPAGES; ++j, ++page) + page->zone_device_data = chunk; } NV_INFO(drm, "DMEM: registered %ldMB of device memory\n", size >> 20); @@ -698,7 +694,7 @@ nouveau_dmem_migrate_alloc_and_copy(struct vm_area_struct *vma, if (!dpage || dst_pfns[i] == MIGRATE_PFN_ERROR) continue; - chunk = (void *)hmm_devmem_page_get_drvdata(dpage); + chunk = dpage->zone_device_data; dst_addr = page_to_pfn(dpage) - chunk->pfn_first; dst_addr = (dst_addr << PAGE_SHIFT) + chunk->bo->bo.offset; @@ -862,7 +858,7 @@ nouveau_dmem_convert_pfn(struct nouveau_drm *drm, continue; } - chunk = (void *)hmm_devmem_page_get_drvdata(page); + chunk = page->zone_device_data; addr = page_to_pfn(page) - chunk->pfn_first; addr = (addr + chunk->bo->bo.mem.start) << PAGE_SHIFT; diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 86aa4ec3404c..3d00e9550e77 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -584,36 +584,4 @@ static inline void hmm_mm_destroy(struct mm_struct *mm) {} static inline void hmm_mm_init(struct mm_struct *mm) {} #endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ -#if IS_ENABLED(CONFIG_DEVICE_PRIVATE) -/* - * hmm_devmem_page_set_drvdata - set per-page driver data field - * - * @page: pointer to struct page - * @data: driver data value to set - * - * Because page can not be on lru we have an unsigned long that driver can use - * to store a per page field. This just a simple helper to do that. - */ -static inline void hmm_devmem_page_set_drvdata(struct page *page, - unsigned long data) -{ - page->hmm_data = data; -} - -/* - * hmm_devmem_page_get_drvdata - get per page driver data field - * - * @page: pointer to struct page - * Return: driver data value - */ -static inline unsigned long hmm_devmem_page_get_drvdata(const struct page *page) -{ - return page->hmm_data; -} -#endif /* CONFIG_DEVICE_PRIVATE */ -#else /* IS_ENABLED(CONFIG_HMM) */ -static inline void hmm_mm_destroy(struct mm_struct *mm) {} -static inline void hmm_mm_init(struct mm_struct *mm) {} -#endif /* IS_ENABLED(CONFIG_HMM) */ - #endif /* LINUX_HMM_H */ diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 8ec38b11b361..f33a1289c101 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -158,7 +158,7 @@ struct page { struct { /* ZONE_DEVICE pages */ /** @pgmap: Points to the hosting device page map. */ struct dev_pagemap *pgmap; - unsigned long hmm_data; + void *zone_device_data; unsigned long _zd_pad_1; /* uses mapping */ }; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 17a39d40a556..c0e031c52db5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5886,12 +5886,12 @@ void __ref memmap_init_zone_device(struct zone *zone, __SetPageReserved(page); /* - * ZONE_DEVICE pages union ->lru with a ->pgmap back - * pointer and hmm_data. It is a bug if a ZONE_DEVICE - * page is ever freed or placed on a driver-private list. + * ZONE_DEVICE pages union ->lru with a ->pgmap back pointer + * and zone_device_data. It is a bug if a ZONE_DEVICE page is + * ever freed or placed on a driver-private list. */ page->pgmap = pgmap; - page->hmm_data = 0; + page->zone_device_data = NULL; /* * Mark the block movable so that blocks are reserved for -- cgit v1.2.3 From 43535b0aefab29ea6564e608de4c783ed2ab6c49 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 26 Jun 2019 14:27:23 +0200 Subject: mm: remove the HMM config option All the mm/hmm.c code is better keyed off HMM_MIRROR. Also let nouveau depend on it instead of the mix of a dummy dependency symbol plus the actually selected one. Drop various odd dependencies, as the code is pretty portable. Signed-off-by: Christoph Hellwig Reviewed-by: Ira Weiny Reviewed-by: Jason Gunthorpe Reviewed-by: Dan Williams Signed-off-by: Jason Gunthorpe --- drivers/gpu/drm/nouveau/Kconfig | 3 +-- include/linux/hmm.h | 5 +---- include/linux/mm_types.h | 2 +- mm/Kconfig | 27 ++++----------------------- mm/Makefile | 2 +- mm/hmm.c | 2 -- 6 files changed, 8 insertions(+), 33 deletions(-) (limited to 'include') diff --git a/drivers/gpu/drm/nouveau/Kconfig b/drivers/gpu/drm/nouveau/Kconfig index 6303d203ab1d..66c839d8e9d1 100644 --- a/drivers/gpu/drm/nouveau/Kconfig +++ b/drivers/gpu/drm/nouveau/Kconfig @@ -84,11 +84,10 @@ config DRM_NOUVEAU_BACKLIGHT config DRM_NOUVEAU_SVM bool "(EXPERIMENTAL) Enable SVM (Shared Virtual Memory) support" - depends on ARCH_HAS_HMM depends on DEVICE_PRIVATE depends on DRM_NOUVEAU + depends on HMM_MIRROR depends on STAGING - select HMM_MIRROR default n help Say Y here if you want to enable experimental support for diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 3d00e9550e77..b697496e85ba 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -62,7 +62,7 @@ #include #include -#if IS_ENABLED(CONFIG_HMM) +#ifdef CONFIG_HMM_MIRROR #include #include @@ -332,9 +332,6 @@ static inline uint64_t hmm_pfn_from_pfn(const struct hmm_range *range, return hmm_device_entry_from_pfn(range, pfn); } - - -#if IS_ENABLED(CONFIG_HMM_MIRROR) /* * Mirroring: how to synchronize device page table with CPU page table. * diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index f33a1289c101..8d37182f8dbe 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -501,7 +501,7 @@ struct mm_struct { #endif struct work_struct async_put_work; -#if IS_ENABLED(CONFIG_HMM) +#ifdef CONFIG_HMM_MIRROR /* HMM needs to track a few things per mm */ struct hmm *hmm; #endif diff --git a/mm/Kconfig b/mm/Kconfig index eecf037a54b3..1e426c26b1d6 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -669,37 +669,18 @@ config ZONE_DEVICE If FS_DAX is enabled, then say Y. -config ARCH_HAS_HMM_MIRROR - bool - default y - depends on (X86_64 || PPC64) - depends on MMU && 64BIT - -config ARCH_HAS_HMM - bool - depends on (X86_64 || PPC64) - depends on ZONE_DEVICE - depends on MMU && 64BIT - depends on MEMORY_HOTPLUG - depends on MEMORY_HOTREMOVE - depends on SPARSEMEM_VMEMMAP - default y - config MIGRATE_VMA_HELPER bool config DEV_PAGEMAP_OPS bool -config HMM - bool - select MMU_NOTIFIER - select MIGRATE_VMA_HELPER - config HMM_MIRROR bool "HMM mirror CPU page table into a device page table" - depends on ARCH_HAS_HMM - select HMM + depends on (X86_64 || PPC64) + depends on MMU && 64BIT + select MMU_NOTIFIER + select MIGRATE_VMA_HELPER help Select HMM_MIRROR if you want to mirror range of the CPU page table of a process into a device page table. Here, mirror means "keep synchronized". diff --git a/mm/Makefile b/mm/Makefile index ac5e5ba78874..91c99040065c 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -102,5 +102,5 @@ obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o obj-$(CONFIG_DEBUG_PAGE_REF) += debug_page_ref.o obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o obj-$(CONFIG_PERCPU_STATS) += percpu-stats.o -obj-$(CONFIG_HMM) += hmm.o +obj-$(CONFIG_HMM_MIRROR) += hmm.o obj-$(CONFIG_MEMFD_CREATE) += memfd.o diff --git a/mm/hmm.c b/mm/hmm.c index 90ca0cdab9db..d62ce64d6bca 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -25,7 +25,6 @@ #include #include -#if IS_ENABLED(CONFIG_HMM_MIRROR) static const struct mmu_notifier_ops hmm_mmu_notifier_ops; static inline struct hmm *mm_get_hmm(struct mm_struct *mm) @@ -1326,4 +1325,3 @@ long hmm_range_dma_unmap(struct hmm_range *range, return cpages; } EXPORT_SYMBOL(hmm_range_dma_unmap); -#endif /* IS_ENABLED(CONFIG_HMM_MIRROR) */ -- cgit v1.2.3