Linux-f2fs-devel Archive on lore.kernel.org
 help / color / Atom feed
* [f2fs-dev] [PATCH 01/10] include/linux/pagemap.h: introduce attach/detach_page_private
       [not found] <20200517214718.468-1-guoqing.jiang@cloud.ionos.com>
@ 2020-05-17 21:47 ` Guoqing Jiang
  2020-05-17 21:47 ` [f2fs-dev] [PATCH 05/10] f2fs: use attach/detach_page_private Guoqing Jiang
  1 sibling, 0 replies; 2+ messages in thread
From: Guoqing Jiang @ 2020-05-17 21:47 UTC (permalink / raw)
  To: akpm, viro
  Cc: Martin Brandenburg, Sebastian Andrzej Siewior, david, Song Liu,
	Yafang Shao, Mike Marshall, Andreas Gruenbacher, Darrick J. Wong,
	Chris Mason, willy, hch, devel, Josef Bacik, linux-raid,
	David Sterba, Jaegeuk Kim, Thomas Gleixner, Anton Altaparmakov,
	Andreas Dilger, Guoqing Jiang, Yang Shi, William Kucharski,
	linux-ntfs-dev, linux-kernel, linux-f2fs-devel, linux-xfs,
	Kirill A. Shutemov, linux-fsdevel, Roman Gushchin, linux-btrfs

The logic in attach_page_buffers and  __clear_page_buffers are quite
paired, but

1. they are located in different files.

2. attach_page_buffers is implemented in buffer_head.h, so it could be
   used by other files. But __clear_page_buffers is static function in
   buffer.c and other potential users can't call the function, md-bitmap
   even copied the function.

So, introduce the new attach/detach_page_private to replace them. With
the new pair of function, we will remove the usage of attach_page_buffers
and  __clear_page_buffers in next patches. Thanks for suggestions about
the function name from Alexander Viro, Andreas Grünbacher, Christoph
Hellwig and Matthew Wilcox.

Suggested-by: Matthew Wilcox <willy@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yafang Shao <laoar.shao@gmail.com>
Cc: Song Liu <song@kernel.org>
Cc: linux-raid@vger.kernel.org
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Cc: David Sterba <dsterba@suse.com>
Cc: linux-btrfs@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: Christoph Hellwig <hch@infradead.org>
Cc: linux-xfs@vger.kernel.org
Cc: Anton Altaparmakov <anton@tuxera.com>
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Roman Gushchin <guro@fb.com>
Cc: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
---
No change since RFC V3.

RFC V2 -> RFC V3:
1. rename clear_page_private to detach_page_private.
2. updated the comments for the two functions.

RFC -> RFC V2:  Address the comments from Christoph Hellwig
1. change function names to attach/clear_page_private and add comments.
2. change the return type of attach_page_private.

 include/linux/pagemap.h | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index c6348c50136f..8e085713150c 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -208,6 +208,43 @@ static inline int page_cache_add_speculative(struct page *page, int count)
 	return __page_cache_add_speculative(page, count);
 }
 
+/**
+ * attach_page_private - Attach private data to a page.
+ * @page: Page to attach data to.
+ * @data: Data to attach to page.
+ *
+ * Attaching private data to a page increments the page's reference count.
+ * The data must be detached before the page will be freed.
+ */
+static inline void attach_page_private(struct page *page, void *data)
+{
+	get_page(page);
+	set_page_private(page, (unsigned long)data);
+	SetPagePrivate(page);
+}
+
+/**
+ * detach_page_private - Detach private data from a page.
+ * @page: Page to detach data from.
+ *
+ * Removes the data that was previously attached to the page and decrements
+ * the refcount on the page.
+ *
+ * Return: Data that was attached to the page.
+ */
+static inline void *detach_page_private(struct page *page)
+{
+	void *data = (void *)page_private(page);
+
+	if (!PagePrivate(page))
+		return NULL;
+	ClearPagePrivate(page);
+	set_page_private(page, 0);
+	put_page(page);
+
+	return data;
+}
+
 #ifdef CONFIG_NUMA
 extern struct page *__page_cache_alloc(gfp_t gfp);
 #else
-- 
2.17.1



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

^ permalink raw reply	[flat|nested] 2+ messages in thread

* [f2fs-dev] [PATCH 05/10] f2fs: use attach/detach_page_private
       [not found] <20200517214718.468-1-guoqing.jiang@cloud.ionos.com>
  2020-05-17 21:47 ` [f2fs-dev] [PATCH 01/10] include/linux/pagemap.h: introduce attach/detach_page_private Guoqing Jiang
@ 2020-05-17 21:47 ` Guoqing Jiang
  1 sibling, 0 replies; 2+ messages in thread
From: Guoqing Jiang @ 2020-05-17 21:47 UTC (permalink / raw)
  To: akpm, viro
  Cc: Guoqing Jiang, david, linux-kernel, willy, linux-f2fs-devel, hch,
	linux-fsdevel, Jaegeuk Kim

Since the new pair function is introduced, we can call them to clean the
code in f2fs.h.

Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Chao Yu <chao@kernel.org>
Cc: linux-f2fs-devel@lists.sourceforge.net
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
---
No change since RFC V3.

RFC V2 -> RFC V3
1. rename clear_page_private to detach_page_private.

RFC -> RFC V2
1. change the name of new functions to attach/clear_page_private.

 fs/f2fs/f2fs.h | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 3574629b75ba..a4d4a947f603 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -3128,19 +3128,12 @@ static inline void f2fs_set_page_private(struct page *page,
 	if (PagePrivate(page))
 		return;
 
-	get_page(page);
-	SetPagePrivate(page);
-	set_page_private(page, data);
+	attach_page_private(page, (void *)data);
 }
 
 static inline void f2fs_clear_page_private(struct page *page)
 {
-	if (!PagePrivate(page))
-		return;
-
-	set_page_private(page, 0);
-	ClearPagePrivate(page);
-	f2fs_put_page(page, 0);
+	detach_page_private(page);
 }
 
 /*
-- 
2.17.1



_______________________________________________
Linux-f2fs-devel mailing list
Linux-f2fs-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, back to index

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <20200517214718.468-1-guoqing.jiang@cloud.ionos.com>
2020-05-17 21:47 ` [f2fs-dev] [PATCH 01/10] include/linux/pagemap.h: introduce attach/detach_page_private Guoqing Jiang
2020-05-17 21:47 ` [f2fs-dev] [PATCH 05/10] f2fs: use attach/detach_page_private Guoqing Jiang

Linux-f2fs-devel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-f2fs-devel/0 linux-f2fs-devel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-f2fs-devel linux-f2fs-devel/ https://lore.kernel.org/linux-f2fs-devel \
		linux-f2fs-devel@lists.sourceforge.net
	public-inbox-index linux-f2fs-devel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/net.sourceforge.lists.linux-f2fs-devel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git