Commit 85d4d2eb authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle)
Browse files

mm/writeback: Add filemap_dirty_folio() 



Reimplement __set_page_dirty_nobuffers() as a wrapper around
filemap_dirty_folio().  Eventually folio_mark_dirty() will pass
the folio's mapping to the address space's ->dirty_folio()
operation, so add the parameter to filemap_dirty_folio() now.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid Howells <dhowells@redhat.com>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
parent b9b0ff61

include/linux/writeback.h

+1 −0
Original line number Diff line number Diff line
@@ -393,6 +393,7 @@ void writeback_set_ratelimit(void); 
void tag_pages_for_writeback(struct address_space *mapping,

			     pgoff_t start, pgoff_t end);



bool filemap_dirty_folio(struct address_space *mapping, struct folio *folio);

void account_page_redirty(struct page *page);



void sb_mark_inode_writeback(struct inode *inode);

mm/folio-compat.c

+6 −0
Original line number Diff line number Diff line
@@ -83,3 +83,9 @@ bool set_page_dirty(struct page *page) 
	return folio_mark_dirty(page_folio(page));

}

EXPORT_SYMBOL(set_page_dirty);



int __set_page_dirty_nobuffers(struct page *page)

{

	return filemap_dirty_folio(page_mapping(page), page_folio(page));

}

EXPORT_SYMBOL(__set_page_dirty_nobuffers);

mm/page-writeback.c

+31 −29
Original line number Diff line number Diff line
@@ -2505,41 +2505,43 @@ void __folio_mark_dirty(struct folio *folio, struct address_space *mapping, 
	xa_unlock_irqrestore(&mapping->i_pages, flags);

}



/*

 * For address_spaces which do not use buffers.  Just tag the page as dirty in

 * the xarray.

/**

 * filemap_dirty_folio - Mark a folio dirty for filesystems which do not use buffer_heads.

 * @mapping: Address space this folio belongs to.

 * @folio: Folio to be marked as dirty.

 *

 * Filesystems which do not use buffer heads should call this function

 * from their set_page_dirty address space operation.  It ignores the

 * contents of folio_get_private(), so if the filesystem marks individual

 * blocks as dirty, the filesystem should handle that itself.

 *

 * This is also used when a single buffer is being dirtied: we want to set the

 * page dirty in that case, but not all the buffers.  This is a "bottom-up"

 * dirtying, whereas __set_page_dirty_buffers() is a "top-down" dirtying.

 * This is also sometimes used by filesystems which use buffer_heads when

 * a single buffer is being dirtied: we want to set the folio dirty in

 * that case, but not all the buffers.  This is a "bottom-up" dirtying,

 * whereas __set_page_dirty_buffers() is a "top-down" dirtying.

 *

 * The caller must ensure this doesn't race with truncation.  Most will simply

 * hold the page lock, but e.g. zap_pte_range() calls with the page mapped and

 * the pte lock held, which also locks out truncation.

 * The caller must ensure this doesn't race with truncation.  Most will

 * simply hold the folio lock, but e.g. zap_pte_range() calls with the

 * folio mapped and the pte lock held, which also locks out truncation.

 */

int __set_page_dirty_nobuffers(struct page *page)

bool filemap_dirty_folio(struct address_space *mapping, struct folio *folio)

{

	lock_page_memcg(page);

	if (!TestSetPageDirty(page)) {

		struct address_space *mapping = page_mapping(page);



		if (!mapping) {

			unlock_page_memcg(page);

			return 1;

	folio_memcg_lock(folio);

	if (folio_test_set_dirty(folio)) {

		folio_memcg_unlock(folio);

		return false;

	}

		__set_page_dirty(page, mapping, !PagePrivate(page));

		unlock_page_memcg(page);



	__folio_mark_dirty(folio, mapping, !folio_test_private(folio));

	folio_memcg_unlock(folio);



	if (mapping->host) {

		/* !PageAnon && !swapper_space */

		__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);

	}

		return 1;

	}

	unlock_page_memcg(page);

	return 0;

	return true;

}

EXPORT_SYMBOL(__set_page_dirty_nobuffers);

EXPORT_SYMBOL(filemap_dirty_folio);



/*

 * Call this whenever redirtying a page, to de-account the dirty counters