diff options
| -rw-r--r-- | include/linux/rmap.h | 1 | ||||
| -rw-r--r-- | include/linux/swap.h | 1 | ||||
| -rw-r--r-- | mm/rmap.c | 29 | ||||
| -rw-r--r-- | mm/swapfile.c | 9 | ||||
| -rw-r--r-- | mm/vmscan.c | 9 |
5 files changed, 49 insertions, 0 deletions
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 0f1ea2d..d6b9bcd 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -92,6 +92,7 @@ static inline void page_dup_rmap(struct page *page) */ int page_referenced(struct page *, int is_locked); int try_to_unmap(struct page *, int ignore_refs); +void remove_from_swap(struct page *page); /* * Called from mm/filemap_xip.c to unmap empty zero page diff --git a/include/linux/swap.h b/include/linux/swap.h index d359fc0..229b6d0 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -248,6 +248,7 @@ extern int remove_exclusive_swap_page(struct page *); struct backing_dev_info; extern spinlock_t swap_lock; +extern int remove_vma_swap(struct vm_area_struct *vma, struct page *page); /* linux/mm/thrash.c */ extern struct mm_struct * swap_token_mm; @@ -206,6 +206,35 @@ out: return anon_vma; } +#ifdef CONFIG_MIGRATION +/* + * Remove an anonymous page from swap replacing the swap pte's + * through real pte's pointing to valid pages and then releasing + * the page from the swap cache. + * + * Must hold page lock on page. + */ +void remove_from_swap(struct page *page) +{ + struct anon_vma *anon_vma; + struct vm_area_struct *vma; + + if (!PageAnon(page) || !PageSwapCache(page)) + return; + + anon_vma = page_lock_anon_vma(page); + if (!anon_vma) + return; + + list_for_each_entry(vma, &anon_vma->head, anon_vma_node) + remove_vma_swap(vma, page); + + spin_unlock(&anon_vma->lock); + + delete_from_swap_cache(page); +} +#endif + /* * At what user virtual address is page expected in vma? */ diff --git a/mm/swapfile.c b/mm/swapfile.c index 9678182..1f9cf0d 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -554,6 +554,15 @@ static int unuse_mm(struct mm_struct *mm, return 0; } +#ifdef CONFIG_MIGRATION +int remove_vma_swap(struct vm_area_struct *vma, struct page *page) +{ + swp_entry_t entry = { .val = page_private(page) }; + + return unuse_vma(vma, entry, page); +} +#endif + /* * Scan swap_map from current position to next entry still in use. * Recycle to start on reaching the end, returning 0 when empty. diff --git a/mm/vmscan.c b/mm/vmscan.c index 8f326ce..5e98b86 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -804,6 +804,15 @@ int migrate_page(struct page *newpage, struct page *page) migrate_page_copy(newpage, page); + /* + * Remove auxiliary swap entries and replace + * them with real ptes. + * + * Note that a real pte entry will allow processes that are not + * waiting on the page lock to use the new page via the page tables + * before the new page is unlocked. + */ + remove_from_swap(newpage); return 0; } |
