From dd19e6d8ffaa1289d75d7833de97faf1b6b2c8e4 Mon Sep 17 00:00:00 2001 From: Alex Sierra Date: Fri, 15 Jul 2022 10:05:12 -0500 Subject: mm: add device coherent vma selection for memory migration This case is used to migrate pages from device memory, back to system memory. Device coherent type memory is cache coherent from device and CPU point of view. Link: https://lkml.kernel.org/r/20220715150521.18165-6-alex.sierra@amd.com Signed-off-by: Alex Sierra Signed-off-by: Christoph Hellwig Acked-by: Felix Kuehling Reviewed-by: Alistair Poppple Reviewed-by: David Hildenbrand Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: Matthew Wilcox Cc: Ralph Campbell Signed-off-by: Andrew Morton --- include/linux/migrate.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 069a89e847f3..b84908debe5c 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -148,6 +148,7 @@ static inline unsigned long migrate_pfn(unsigned long pfn) enum migrate_vma_direction { MIGRATE_VMA_SELECT_SYSTEM = 1 << 0, MIGRATE_VMA_SELECT_DEVICE_PRIVATE = 1 << 1, + MIGRATE_VMA_SELECT_DEVICE_COHERENT = 1 << 2, }; struct migrate_vma { -- cgit v1.2.3 From 68f2736a858324c3ec852f6c2cddd9d1c777357d Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Tue, 7 Jun 2022 15:38:48 -0400 Subject: mm: Convert all PageMovable users to movable_operations These drivers are rather uncomfortably hammered into the address_space_operations hole. They aren't filesystems and don't behave like filesystems. They just need their own movable_operations structure, which we can point to directly from page->mapping. Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/migrate.h | 56 ++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 51 insertions(+), 5 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 069a89e847f3..82c735ba6109 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -19,6 +19,43 @@ struct migration_target_control; */ #define MIGRATEPAGE_SUCCESS 0 +/** + * struct movable_operations - Driver page migration + * @isolate_page: + * The VM calls this function to prepare the page to be moved. The page + * is locked and the driver should not unlock it. The driver should + * return ``true`` if the page is movable and ``false`` if it is not + * currently movable. After this function returns, the VM uses the + * page->lru field, so the driver must preserve any information which + * is usually stored here. + * + * @migrate_page: + * After isolation, the VM calls this function with the isolated + * @src page. The driver should copy the contents of the + * @src page to the @dst page and set up the fields of @dst page. + * Both pages are locked. + * If page migration is successful, the driver should call + * __ClearPageMovable(@src) and return MIGRATEPAGE_SUCCESS. + * If the driver cannot migrate the page at the moment, it can return + * -EAGAIN. The VM interprets this as a temporary migration failure and + * will retry it later. Any other error value is a permanent migration + * failure and migration will not be retried. + * The driver shouldn't touch the @src->lru field while in the + * migrate_page() function. It may write to @dst->lru. + * + * @putback_page: + * If migration fails on the isolated page, the VM informs the driver + * that the page is no longer a candidate for migration by calling + * this function. The driver should put the isolated page back into + * its own data structure. + */ +struct movable_operations { + bool (*isolate_page)(struct page *, isolate_mode_t); + int (*migrate_page)(struct page *dst, struct page *src, + enum migrate_mode); + void (*putback_page)(struct page *); +}; + /* Defined in mm/debug.c: */ extern const char *migrate_reason_names[MR_TYPES]; @@ -91,13 +128,13 @@ static inline int next_demotion_node(int node) #endif #ifdef CONFIG_COMPACTION -extern int PageMovable(struct page *page); -extern void __SetPageMovable(struct page *page, struct address_space *mapping); -extern void __ClearPageMovable(struct page *page); +bool PageMovable(struct page *page); +void __SetPageMovable(struct page *page, const struct movable_operations *ops); +void __ClearPageMovable(struct page *page); #else -static inline int PageMovable(struct page *page) { return 0; } +static inline bool PageMovable(struct page *page) { return false; } static inline void __SetPageMovable(struct page *page, - struct address_space *mapping) + const struct movable_operations *ops) { } static inline void __ClearPageMovable(struct page *page) @@ -110,6 +147,15 @@ static inline bool folio_test_movable(struct folio *folio) return PageMovable(&folio->page); } +static inline +const struct movable_operations *page_movable_ops(struct page *page) +{ + VM_BUG_ON(!__PageMovable(page)); + + return (const struct movable_operations *) + ((unsigned long)page->mapping - PAGE_MAPPING_MOVABLE); +} + #ifdef CONFIG_NUMA_BALANCING extern int migrate_misplaced_page(struct page *page, struct vm_area_struct *vma, int node); -- cgit v1.2.3 From 541846502f4fe826cd7c16e4784695ac90736585 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 6 Jun 2022 10:27:41 -0400 Subject: mm/migrate: Convert migrate_page() to migrate_folio() Convert all callers to pass a folio. Most have the folio already available. Switch all users from aops->migratepage to aops->migrate_folio. Also turn the documentation into kerneldoc. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Acked-by: David Sterba --- include/linux/migrate.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 82c735ba6109..c9986d5da335 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -62,9 +62,8 @@ extern const char *migrate_reason_names[MR_TYPES]; #ifdef CONFIG_MIGRATION extern void putback_movable_pages(struct list_head *l); -extern int migrate_page(struct address_space *mapping, - struct page *newpage, struct page *page, - enum migrate_mode mode); +int migrate_folio(struct address_space *mapping, struct folio *dst, + struct folio *src, enum migrate_mode mode); extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free, unsigned long private, enum migrate_mode mode, int reason, unsigned int *ret_succeeded); -- cgit v1.2.3 From b890ec2a2c2d962f71ba31ae291f8fd252b46258 Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 6 Jun 2022 10:47:21 -0400 Subject: hugetlb: Convert to migrate_folio This involves converting migrate_huge_page_move_mapping(). We also need a folio variant of hugetlb_set_page_subpool(), but that's for a later patch. Signed-off-by: Matthew Wilcox (Oracle) Acked-by: Muchun Song Reviewed-by: Mike Kravetz --- include/linux/migrate.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index c9986d5da335..13f793309b75 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -72,8 +72,8 @@ extern int isolate_movable_page(struct page *page, isolate_mode_t mode); extern void migrate_page_states(struct page *newpage, struct page *page); extern void migrate_page_copy(struct page *newpage, struct page *page); -extern int migrate_huge_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page); +int migrate_huge_page_move_mapping(struct address_space *mapping, + struct folio *dst, struct folio *src); extern int migrate_page_move_mapping(struct address_space *mapping, struct page *newpage, struct page *page, int extra_count); void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep, @@ -104,7 +104,7 @@ static inline void migrate_page_copy(struct page *newpage, struct page *page) {} static inline int migrate_huge_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page) + struct folio *dst, struct folio *src) { return -ENOSYS; } -- cgit v1.2.3 From 9800562f2ab41656b0bdc2a41c77ab3f6dfdd6fc Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 6 Jun 2022 13:29:10 -0400 Subject: mm/folio-compat: Remove migration compatibility functions migrate_page_move_mapping(), migrate_page_copy() and migrate_page_states() are all now unused after converting all the filesystems from aops->migratepage() to aops->migrate_folio(). Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig --- include/linux/migrate.h | 11 ----------- 1 file changed, 11 deletions(-) (limited to 'include/linux/migrate.h') diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 13f793309b75..ae5bb67a9ba1 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -70,12 +70,8 @@ extern int migrate_pages(struct list_head *l, new_page_t new, free_page_t free, extern struct page *alloc_migration_target(struct page *page, unsigned long private); extern int isolate_movable_page(struct page *page, isolate_mode_t mode); -extern void migrate_page_states(struct page *newpage, struct page *page); -extern void migrate_page_copy(struct page *newpage, struct page *page); int migrate_huge_page_move_mapping(struct address_space *mapping, struct folio *dst, struct folio *src); -extern int migrate_page_move_mapping(struct address_space *mapping, - struct page *newpage, struct page *page, int extra_count); void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep, spinlock_t *ptl); void folio_migrate_flags(struct folio *newfolio, struct folio *folio); @@ -96,13 +92,6 @@ static inline struct page *alloc_migration_target(struct page *page, static inline int isolate_movable_page(struct page *page, isolate_mode_t mode) { return -EBUSY; } -static inline void migrate_page_states(struct page *newpage, struct page *page) -{ -} - -static inline void migrate_page_copy(struct page *newpage, - struct page *page) {} - static inline int migrate_huge_page_move_mapping(struct address_space *mapping, struct folio *dst, struct folio *src) { -- cgit v1.2.3