linux-kernel - [PATCH 03/13] fs/dax: Refactor wait for dax idle page

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 27 Jun 2024 10:54:18 +1000
From: Alistair Popple <apopple@...dia.com>
To: dan.j.williams@...el.com,
	vishal.l.verma@...el.com,
	dave.jiang@...el.com,
	logang@...tatee.com,
	bhelgaas@...gle.com,
	jack@...e.cz,
	jgg@...pe.ca
Cc: catalin.marinas@....com,
	will@...nel.org,
	mpe@...erman.id.au,
	npiggin@...il.com,
	dave.hansen@...ux.intel.com,
	ira.weiny@...el.com,
	willy@...radead.org,
	djwong@...nel.org,
	tytso@....edu,
	linmiaohe@...wei.com,
	david@...hat.com,
	peterx@...hat.com,
	linux-doc@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linuxppc-dev@...ts.ozlabs.org,
	nvdimm@...ts.linux.dev,
	linux-cxl@...r.kernel.org,
	linux-fsdevel@...r.kernel.org,
	linux-mm@...ck.org,
	linux-ext4@...r.kernel.org,
	linux-xfs@...r.kernel.org,
	jhubbard@...dia.com,
	hch@....de,
	david@...morbit.com,
	Alistair Popple <apopple@...dia.com>
Subject: [PATCH 03/13] fs/dax: Refactor wait for dax idle page

A FS DAX page is considered idle when its refcount drops to one. This
is currently open-coded in all file systems supporting FS DAX. Move
the idle detection to a common function to make future changes easier.

Signed-off-by: Alistair Popple <apopple@...dia.com>
Reviewed-by: Jan Kara <jack@...e.cz>
---
 fs/ext4/inode.c     | 5 +----
 fs/fuse/dax.c       | 4 +---
 fs/xfs/xfs_inode.c  | 4 +---
 include/linux/dax.h | 8 ++++++++
 4 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 4bae9cc..4737450 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3844,10 +3844,7 @@ int ext4_break_layouts(struct inode *inode)
 		if (!page)
 			return 0;
 
-		error = ___wait_var_event(&page->_refcount,
-				atomic_read(&page->_refcount) == 1,
-				TASK_INTERRUPTIBLE, 0, 0,
-				ext4_wait_dax_page(inode));
+		error = dax_wait_page_idle(page, ext4_wait_dax_page, inode);
 	} while (error == 0);
 
 	return error;
diff --git a/fs/fuse/dax.c b/fs/fuse/dax.c
index 12ef91d..da50595 100644
--- a/fs/fuse/dax.c
+++ b/fs/fuse/dax.c
@@ -676,9 +676,7 @@ static int __fuse_dax_break_layouts(struct inode *inode, bool *retry,
 		return 0;
 
 	*retry = true;
-	return ___wait_var_event(&page->_refcount,
-			atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
-			0, 0, fuse_wait_dax_page(inode));
+	return dax_wait_page_idle(page, fuse_wait_dax_page, inode);
 }
 
 /* dmap_end == 0 leads to unmapping of whole file */
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index f36091e..b5742aa 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -4243,9 +4243,7 @@ xfs_break_dax_layouts(
 		return 0;
 
 	*retry = true;
-	return ___wait_var_event(&page->_refcount,
-			atomic_read(&page->_refcount) == 1, TASK_INTERRUPTIBLE,
-			0, 0, xfs_wait_dax_page(inode));
+	return dax_wait_page_idle(page, xfs_wait_dax_page, inode);
 }
 
 int
diff --git a/include/linux/dax.h b/include/linux/dax.h
index 9d3e332..773dfc4 100644
--- a/include/linux/dax.h
+++ b/include/linux/dax.h
@@ -213,6 +213,14 @@ int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
 int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
 		const struct iomap_ops *ops);
 
+static inline int dax_wait_page_idle(struct page *page,
+				void (cb)(struct inode *),
+				struct inode *inode)
+{
+	return ___wait_var_event(page, page_ref_count(page) == 1,
+				TASK_INTERRUPTIBLE, 0, 0, cb(inode));
+}
+
 #if IS_ENABLED(CONFIG_DAX)
 int dax_read_lock(void);
 void dax_read_unlock(int id);
-- 
git-series 0.9.1