From 85430c22e5ae87eff7b491d7a363c81325b94b8a Mon Sep 17 00:00:00 2001 From: Hao Li Date: Wed, 6 Jan 2021 09:50:00 +0800 Subject: Documentation/dax: Update description of DAX policy changing After commit 77573fa310d9 ("fs: Kill DCACHE_DONTCACHE dentry even if DCACHE_REFERENCED is set"), changes to DAX policy will take effect as soon as all references to this file are gone. Update the documentation accordingly. Signed-off-by: Hao Li Reviewed-by: Ira Weiny Link: https://lore.kernel.org/r/20210106015000.5263-1-lihao2018.fnst@cn.fujitsu.com Signed-off-by: Jonathan Corbet --- Documentation/filesystems/dax.txt | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/dax.txt b/Documentation/filesystems/dax.txt index 8fdb78f3c6c9..e03c20564f3a 100644 --- a/Documentation/filesystems/dax.txt +++ b/Documentation/filesystems/dax.txt @@ -83,20 +83,9 @@ Summary directories. This has runtime constraints and limitations that are described in 6) below. - 6. When changing the S_DAX policy via toggling the persistent FS_XFLAG_DAX flag, - the change in behaviour for existing regular files may not occur - immediately. If the change must take effect immediately, the administrator - needs to: - - a) stop the application so there are no active references to the data set - the policy change will affect - - b) evict the data set from kernel caches so it will be re-instantiated when - the application is restarted. This can be achieved by: - - i. drop-caches - ii. a filesystem unmount and mount cycle - iii. a system reboot + 6. When changing the S_DAX policy via toggling the persistent FS_XFLAG_DAX + flag, the change to existing regular files won't take effect until the + files are closed by all processes. Details -- cgit v1.2.3-59-g8ed1b