From 19c5246d251640ac76daa4d34165af78c64b1454 Mon Sep 17 00:00:00 2001 From: Yongqiang Yang Date: Wed, 4 Jan 2012 17:09:44 -0500 Subject: ext4: add new online resize interface This patch adds new online resize interface, whose input argument is a 64-bit integer indicating how many blocks there are in the resized fs. In new resize impelmentation, all work like allocating group tables are done by kernel side, so the new resize interface can support flex_bg feature and prepares ground for suppoting resize with features like bigalloc and exclude bitmap. Besides these, user-space tools just passes in the new number of blocks. We delay initializing the bitmaps and inode tables of added groups if possible and add multi groups (a flex groups) each time, so new resize is very fast like mkfs. Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" --- Documentation/filesystems/ext4.txt | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'Documentation/filesystems/ext4.txt') diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 4917cf24a5e..10ec4639f15 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -581,6 +581,13 @@ Table of Ext4 specific ioctls behaviour may change in the future as it is not necessary and has been done this way only for sake of simplicity. + + EXT4_IOC_RESIZE_FS Resize the filesystem to a new size. The number + of blocks of resized filesystem is passed in via + 64 bit integer argument. The kernel allocates + bitmaps and inode table, the userspace tool thus + just passes the new number of blocks. + .............................................................................. References -- cgit v1.2.3