Reimplement set_page_dirty() as a wrapper around folio_mark_dirty().
There is no change to filesystems as they were already being called
with the compound_head of the page being marked dirty. We avoid
several calls to compound_head(), both statically (through
using folio_dirty() instead of PageDirty() and dynamically by
calling folio_mapping() instead of page_mapping().
Also return bool instead of int to show the range of values actually
returned, and add kernel-doc.
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/mm.h | 3 ++-
mm/folio-compat.c | 6 ++++++
mm/page-writeback.c | 28 +++++++++++++++-------------
3 files changed, 23 insertions(+), 14 deletions(-)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 75279db82040..c72cecbfe00d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1998,7 +1998,8 @@ int redirty_page_for_writepage(struct writeback_control *wbc,
void account_page_dirtied(struct page *page, struct address_space *mapping);
void account_page_cleaned(struct page *page, struct address_space *mapping,
struct bdi_writeback *wb);
-int set_page_dirty(struct page *page);
+bool folio_mark_dirty(struct folio *folio);
+bool set_page_dirty(struct page *page);
int set_page_dirty_lock(struct page *page);
void __cancel_dirty_page(struct page *page);
static inline void cancel_dirty_page(struct page *page)
diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index d229b979b00d..a504ecf1d695 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c
@@ -60,3 +60,9 @@ void mem_cgroup_uncharge(struct page *page)
folio_uncharge_cgroup(page_folio(page));
}
#endif
+
+bool set_page_dirty(struct page *page)
+{
+ return folio_mark_dirty(page_folio(page));
+}
+EXPORT_SYMBOL(set_page_dirty);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 4d36f4d3037f..d810841ed03a 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2543,8 +2543,9 @@ int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
}
EXPORT_SYMBOL(redirty_page_for_writepage);
-/*
- * Dirty a page.
+/**
+ * folio_mark_dirty - Mark a folio as being modified.
+ * @folio: The folio.
*
* For pages with a mapping this should be done under the page lock
* for the benefit of asynchronous memory errors who prefer a consistent
@@ -2553,12 +2554,13 @@ EXPORT_SYMBOL(redirty_page_for_writepage);
*
* If the mapping doesn't provide a set_page_dirty a_op, then
* just fall through and assume that it wants buffer_heads.
+ *
+ * Return: True if the folio was newly dirtied, false if it was already dirty.
*/
-int set_page_dirty(struct page *page)
+bool folio_mark_dirty(struct folio *folio)
{
- struct address_space *mapping = page_mapping(page);
+ struct address_space *mapping = folio_mapping(folio);
- page = compound_head(page);
if (likely(mapping)) {
int (*spd)(struct page *) = mapping->a_ops->set_page_dirty;
/*
@@ -2571,21 +2573,21 @@ int set_page_dirty(struct page *page)
* it will confuse readahead and make it restart the size rampup
* process. But it's a trivial problem.
*/
- if (PageReclaim(page))
- ClearPageReclaim(page);
+ if (folio_reclaim(folio))
+ folio_clear_reclaim_flag(folio);
#ifdef CONFIG_BLOCK
if (!spd)
spd = __set_page_dirty_buffers;
#endif
- return (*spd)(page);
+ return (*spd)(&folio->page);
}
- if (!PageDirty(page)) {
- if (!TestSetPageDirty(page))
- return 1;
+ if (!folio_dirty(folio)) {
+ if (!folio_test_set_dirty_flag(folio))
+ return true;
}
- return 0;
+ return false;
}
-EXPORT_SYMBOL(set_page_dirty);
+EXPORT_SYMBOL(folio_mark_dirty);
/*
* set_page_dirty() is racy if the caller has no reference against
--
2.30.2
