diff options
| -rw-r--r-- | Documentation/filesystems/locking.rst | 15 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.rst | 16 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 | ||||
| -rw-r--r-- | mm/page-writeback.c | 17 | ||||
| -rw-r--r-- | mm/page_io.c | 5 |
5 files changed, 31 insertions, 23 deletions
diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst index dee512efb458..72fa12dabd39 100644 --- a/Documentation/filesystems/locking.rst +++ b/Documentation/filesystems/locking.rst @@ -239,7 +239,7 @@ prototypes:: int (*writepage)(struct page *page, struct writeback_control *wbc); int (*readpage)(struct file *, struct page *); int (*writepages)(struct address_space *, struct writeback_control *); - int (*set_page_dirty)(struct page *page); + bool (*dirty_folio)(struct address_space *, struct folio *folio); void (*readahead)(struct readahead_control *); int (*readpages)(struct file *filp, struct address_space *mapping, struct list_head *pages, unsigned nr_pages); @@ -264,7 +264,7 @@ prototypes:: int (*swap_deactivate)(struct file *); locking rules: - All except set_page_dirty and freepage may block + All except dirty_folio and freepage may block ====================== ======================== ========= =============== ops PageLocked(page) i_rwsem invalidate_lock @@ -272,7 +272,7 @@ ops PageLocked(page) i_rwsem invalidate_lock writepage: yes, unlocks (see below) readpage: yes, unlocks shared writepages: -set_page_dirty no +dirty_folio maybe readahead: yes, unlocks shared readpages: no shared write_begin: locks the page exclusive @@ -361,10 +361,11 @@ If nr_to_write is NULL, all dirty pages must be written. writepages should _only_ write pages which are present on mapping->io_pages. -->set_page_dirty() is called from various places in the kernel -when the target page is marked as needing writeback. It may be called -under spinlock (it cannot block) and is sometimes called with the page -not locked. +->dirty_folio() is called from various places in the kernel when +the target folio is marked as needing writeback. The folio cannot be +truncated because either the caller holds the folio lock, or the caller +has found the folio while holding the page table lock which will block +truncation. ->bmap() is currently used by legacy ioctl() (FIBMAP) provided by some filesystems and by the swapper. The latter will eventually go away. Please, diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index c54ca4d88ed6..d16bee420326 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -658,7 +658,7 @@ pages, however the address_space has finer control of write sizes. The read process essentially only requires 'readpage'. The write process is more complicated and uses write_begin/write_end or -set_page_dirty to write data into the address_space, and writepage and +dirty_folio to write data into the address_space, and writepage and writepages to writeback data to storage. Adding and removing pages to/from an address_space is protected by the @@ -724,7 +724,7 @@ cache in your filesystem. The following members are defined: int (*writepage)(struct page *page, struct writeback_control *wbc); int (*readpage)(struct file *, struct page *); int (*writepages)(struct address_space *, struct writeback_control *); - int (*set_page_dirty)(struct page *page); + bool (*dirty_folio)(struct address_space *, struct folio *); void (*readahead)(struct readahead_control *); int (*readpages)(struct file *filp, struct address_space *mapping, struct list_head *pages, unsigned nr_pages); @@ -793,13 +793,13 @@ cache in your filesystem. The following members are defined: This will choose pages from the address space that are tagged as DIRTY and will pass them to ->writepage. -``set_page_dirty`` - called by the VM to set a page dirty. This is particularly - needed if an address space attaches private data to a page, and - that data needs to be updated when a page is dirtied. This is +``dirty_folio`` + called by the VM to mark a folio as dirty. This is particularly + needed if an address space attaches private data to a folio, and + that data needs to be updated when a folio is dirtied. This is called, for example, when a memory mapped page gets modified. - If defined, it should set the PageDirty flag, and the - PAGECACHE_TAG_DIRTY tag in the radix tree. + If defined, it should set the folio dirty flag, and the + PAGECACHE_TAG_DIRTY search mark in i_pages. ``readahead`` Called by the VM to read pages associated with the address_space diff --git a/include/linux/fs.h b/include/linux/fs.h index 055be40084f1..c3d5db8851ae 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -369,6 +369,7 @@ struct address_space_operations { /* Set a page dirty. Return true if this dirtied it */ int (*set_page_dirty)(struct page *page); + bool (*dirty_folio)(struct address_space *, struct folio *); /* * Reads in the requested pages. Unlike ->readpage(), this is diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 91d163f8d36b..27a87ae4502c 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2616,7 +2616,7 @@ EXPORT_SYMBOL(folio_redirty_for_writepage); * folio_mark_dirty - Mark a folio as being modified. * @folio: The folio. * - * For folios with a mapping this should be done under the page lock + * For folios with a mapping this should be done with the folio lock held * for the benefit of asynchronous memory errors who prefer a consistent * dirty state. This rule can be broken in some special cases, * but should be better not to. @@ -2630,16 +2630,19 @@ bool folio_mark_dirty(struct folio *folio) if (likely(mapping)) { /* * readahead/lru_deactivate_page could remain - * PG_readahead/PG_reclaim due to race with end_page_writeback - * About readahead, if the page is written, the flags would be + * PG_readahead/PG_reclaim due to race with folio_end_writeback + * About readahead, if the folio is written, the flags would be * reset. So no problem. - * About lru_deactivate_page, if the page is redirty, the flag - * will be reset. So no problem. but if the page is used by readahead - * it will confuse readahead and make it restart the size rampup - * process. But it's a trivial problem. + * About lru_deactivate_page, if the folio is redirtied, + * the flag will be reset. So no problem. but if the + * folio is used by readahead it will confuse readahead + * and make it restart the size rampup process. But it's + * a trivial problem. */ if (folio_test_reclaim(folio)) folio_clear_reclaim(folio); + if (mapping->a_ops->dirty_folio) + return mapping->a_ops->dirty_folio(mapping, folio); return mapping->a_ops->set_page_dirty(&folio->page); } if (!folio_test_dirty(folio)) { diff --git a/mm/page_io.c b/mm/page_io.c index 0bf8e40f4e57..24c975fb4e21 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -444,9 +444,12 @@ int swap_set_page_dirty(struct page *page) if (data_race(sis->flags & SWP_FS_OPS)) { struct address_space *mapping = sis->swap_file->f_mapping; + const struct address_space_operations *aops = mapping->a_ops; VM_BUG_ON_PAGE(!PageSwapCache(page), page); - return mapping->a_ops->set_page_dirty(page); + if (aops->dirty_folio) + return aops->dirty_folio(mapping, page_folio(page)); + return aops->set_page_dirty(page); } else { return __set_page_dirty_no_writeback(page); } |