redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

Documentation/dax: Update description of DAX policy changing 

After commit 77573fa310 ("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 <lihao2018.fnst@cn.fujitsu.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20210106015000.5263-1-lihao2018.fnst@cn.fujitsu.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
master
Hao Li 2021-01-06 09:50:00 +08:00 committed by Jonathan Corbet
parent c4c6b86acf
commit 85430c22e5
1 changed files with 3 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
Documentation/filesystems/dax.txt
View File

@ -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