From a78d9f0d5d5ca9054703376c7c23c901807ddd87 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Sat, 13 Dec 2014 00:59:52 +0100 Subject: ovl: support multiple lower layers Allow "lowerdir=" option to contain multiple lower directories separated by a colon (e.g. "lowerdir=/bin:/usr/bin"). Colon characters in filenames can be escaped with a backslash. Signed-off-by: Miklos Szeredi --- Documentation/filesystems/overlayfs.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index a27c950ece61..b37092886dcc 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -159,6 +159,18 @@ overlay filesystem (though an operation on the name of the file such as rename or unlink will of course be noticed and handled). +Multiple lower layers +--------------------- + +Multiple lower layers can now be given using the the colon (":") as a +separator character between the directory names. For example: + + mount -t overlay overlay -olowerdir=/lower1:/lower2:/lower3 /merged + +As the example shows, "upperdir=" and "workdir=" may be omitted. In that case +the overlay will be read-only. + + Non-standard behavior --------------------- -- cgit v1.2.2 From 2b7a8f36f092a7855f6438cd42d6990394f450fa Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Sat, 13 Dec 2014 00:59:53 +0100 Subject: ovl: add testsuite to docs Reported-by: Sedat Dilek Signed-off-by: Miklos Szeredi --- Documentation/filesystems/overlayfs.txt | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index b37092886dcc..006ea480506d 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -208,3 +208,15 @@ Changes to the underlying filesystems while part of a mounted overlay filesystem are not allowed. If the underlying filesystem is changed, the behavior of the overlay is undefined, though it will not result in a crash or deadlock. + +Testsuite +--------- + +There's testsuite developed by David Howells at: + + git://git.infradead.org/users/dhowells/unionmount-testsuite.git + +Run as root: + + # cd unionmount-testsuite + # ./run --ov -- cgit v1.2.2 From 6d900f5a33393067e370736d39798f814f5e25cc Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Thu, 8 Jan 2015 15:09:15 +0100 Subject: ovl: document lower layer ordering Reported-by: Fabian Sturm Signed-off-by: Miklos Szeredi --- Documentation/filesystems/overlayfs.txt | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'Documentation/filesystems') diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index 006ea480506d..6db0e5d1da07 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -167,8 +167,12 @@ separator character between the directory names. For example: mount -t overlay overlay -olowerdir=/lower1:/lower2:/lower3 /merged -As the example shows, "upperdir=" and "workdir=" may be omitted. In that case -the overlay will be read-only. +As the example shows, "upperdir=" and "workdir=" may be omitted. In +that case the overlay will be read-only. + +The specified lower directories will be stacked beginning from the +rightmost one and going left. In the above example lower1 will be the +top, lower2 the middle and lower3 the bottom layer. Non-standard behavior -- cgit v1.2.2