[PATCH 3/4] ext4.5: document the stable_inodes feature

From: Eric Biggers <ebiggers@kernel.org>
To: linux-ext4@vger.kernel.org
Cc: linux-fscrypt@vger.kernel.org
Subject: [PATCH 3/4] ext4.5: document the stable_inodes feature
Date: Wed,  1 Apr 2020 13:32:38 -0700	[thread overview]
Message-ID: <20200401203239.163679-4-ebiggers@kernel.org> (raw)
In-Reply-To: <20200401203239.163679-1-ebiggers@kernel.org>

From: Eric Biggers <ebiggers@google.com>

Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 misc/ext4.5.in | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/misc/ext4.5.in b/misc/ext4.5.in
index 1db61a5f..90bc4f88 100644
--- a/misc/ext4.5.in
+++ b/misc/ext4.5.in
@@ -299,6 +299,20 @@ feature is essentially a more extreme version of sparse_super and is
 designed to allow a much larger percentage of the disk to have
 contiguous blocks available for data files.
 .TP
+.B stable_inodes
+.br
+Marks the filesystem's inode numbers and UUID as stable.
+.BR resize2fs (8)
+will not allow shrinking a filesystem with this feature, nor
+will
+.BR tune2fs (8)
+allow changing its UUID.  This feature allows the use of specialized encryption
+settings that make use of the inode numbers and UUID.  Note that the
+.B encrypt
+feature still needs to be enabled separately.
+.B stable_inodes
+is a "compat" feature, so old kernels will allow it.
+.TP
 .B uninit_bg
 .br
 This ext4 file system feature indicates that the block group descriptors
@@ -788,6 +802,8 @@ ext4, 4.13
 ext4, 5.2
 .IP "\fBverity\fR" 2i
 ext4, 5.4
+.IP "\fBstable_inodes\fR" 2i
+ext4, 5.5
 .SH SEE ALSO
 .BR mke2fs (8),
 .BR mke2fs.conf (5),
-- 
2.26.0.rc2.310.g2932bb562d-goog

