From 39ae763229da20664d5eb1673c307e40353c225b Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Wed, 22 Jan 2014 09:35:19 +0200 Subject: [PATCH] RELEASE_NOTES: start release notes for v3.2 Starte preparing bmapt-tools-3.2 release notes and describe the tmpfs and SEEK_HOLE support there. Change-Id: Iba0b8c3d784c55dc566985983a5c44ebd9fc7f64 Signed-off-by: Artem Bityutskiy --- docs/RELEASE_NOTES | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/docs/RELEASE_NOTES b/docs/RELEASE_NOTES index 1c4fe13..d4a9f3a 100644 --- a/docs/RELEASE_NOTES +++ b/docs/RELEASE_NOTES @@ -1,3 +1,22 @@ +Release 3.2 +~~~~~~~~~~~ + +1. Make 'bmaptool create' (and hence, the BmapCreate module) work with the + "tmpfs" file-system. This file-system does not, unfortunately, support the + "FIEMAP" ioctl, but it supports the "SEEK_HOLE" option of the "lseek" system + call, which can also be used to find where the holes are. In this release we + have implemented support for "SEEK_HOLE" to cover tmpfs. Generally, FIEMAP + is faster than "SEEK_HOLE" for large files, so we always try to start with + using FIEMAP, and if it is not supported, we fall-back to using "SEEK_HOLE". + Therefore, the "Fiemap" module was re-named to "Filemap", since it is now + supports more than just the FIEMAP ioctl. + + Unfortunately, the SEEK_HOLE method requires the directory where the image + resides to be accessible for writing, because in current implementation we + need to create a temporary file there for a short time. The temporary file + is used to detect whether SEEK_HOLE is really implemented, or the system + just fakes it by always returning EOF. + Bug-fix release 3.1 ~~~~~~~~~~~~~~~~~~~ -- 2.34.1