[PATCH v13 075/137] mm/writeback: Add folio_redirty_for_writepage()

Matthew Wilcox (Oracle)
2021-07-12T03:48:27Z

Reimplement redirty_page_for_writepage() as a wrapper around
folio_redirty_for_writepage(). Account the number of pages in the
folio, add kernel-doc and move the prototype to writeback.h.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
fs/jfs/jfs_metapage.c | 1 +
include/linux/mm.h | 4 ----
include/linux/writeback.h | 2 ++
mm/folio-compat.c | 7 +++++++
mm/page-writeback.c | 30 ++++++++++++++++++++----------
5 files changed, 30 insertions(+), 14 deletions(-)

diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
index 176580f54af9..104ae698443e 100644
--- a/fs/jfs/jfs_metapage.c
+++ b/fs/jfs/jfs_metapage.c
@@ -13,6 +13,7 @@
#include <linux/buffer_head.h>
#include <linux/mempool.h>
#include <linux/seq_file.h>
+#include <linux/writeback.h>
#include "jfs_incore.h"
#include "jfs_superblock.h"
#include "jfs_filsys.h"
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 93c2b9b6ab7b..862b5be4583e 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -36,9 +36,7 @@
struct mempolicy;
struct anon_vma;
struct anon_vma_chain;
-struct file_ra_state;
struct user_struct;
-struct writeback_control;
struct pt_regs;

extern int sysctl_page_lock_unfairness;
@@ -1999,8 +1997,6 @@ extern int try_to_release_page(struct page * page, gfp_t gfp_mask);
extern void do_invalidatepage(struct page *page, unsigned int offset,
unsigned int length);

-int redirty_page_for_writepage(struct writeback_control *wbc,
- 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);
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 50cb6e25ab9e..5383f7e39816 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -404,6 +404,8 @@ static inline void account_page_redirty(struct page *page)
{
folio_account_redirty(page_folio(page));
}
+bool folio_redirty_for_writepage(struct writeback_control *, struct folio *);
+bool redirty_page_for_writepage(struct writeback_control *, struct page *);

void sb_mark_inode_writeback(struct inode *inode);
void sb_clear_inode_writeback(struct inode *inode);
diff --git a/mm/folio-compat.c b/mm/folio-compat.c
index 39f5a8d963b1..c1e01bc36d32 100644
--- a/mm/folio-compat.c
+++ b/mm/folio-compat.c
@@ -95,3 +95,10 @@ bool clear_page_dirty_for_io(struct page *page)
return folio_clear_dirty_for_io(page_folio(page));
}
EXPORT_SYMBOL(clear_page_dirty_for_io);
+
+bool redirty_page_for_writepage(struct writeback_control *wbc,
+ struct page *page)
+{
+ return folio_redirty_for_writepage(wbc, page_folio(page));
+}
+EXPORT_SYMBOL(redirty_page_for_writepage);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 593b4f4f5f22..1a5677d099ea 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2558,21 +2558,31 @@ void folio_account_redirty(struct folio *folio)
}
EXPORT_SYMBOL(folio_account_redirty);

-/*
- * When a writepage implementation decides that it doesn't want to write this
- * page for some reason, it should redirty the locked page via
- * redirty_page_for_writepage() and it should then unlock the page and return 0
+/**
+ * folio_redirty_for_writepage - Decline to write a dirty folio.
+ * @wbc: The writeback control.
+ * @folio: The folio.
+ *
+ * When a writepage implementation decides that it doesn't want to write
+ * @folio for some reason, it should call this function, unlock @folio and
+ * return 0.
+ *
+ * Return: True if we redirtied the folio. False if someone else dirtied
+ * it first.
*/
-int redirty_page_for_writepage(struct writeback_control *wbc, struct page *page)
+bool folio_redirty_for_writepage(struct writeback_control *wbc,
+ struct folio *folio)
{
- int ret;
+ bool ret;
+ unsigned nr = folio_nr_pages(folio);
+
+ wbc->pages_skipped += nr;
+ ret = filemap_dirty_folio(folio->mapping, folio);
+ folio_account_redirty(folio);

- wbc->pages_skipped++;
- ret = __set_page_dirty_nobuffers(page);
- account_page_redirty(page);
return ret;
}
-EXPORT_SYMBOL(redirty_page_for_writepage);
+EXPORT_SYMBOL(folio_redirty_for_writepage);

/**
* folio_mark_dirty - Mark a folio as being modified.
--
2.30.2