From 06247428be8037b3739280f82cb29efe8397695f Mon Sep 17 00:00:00 2001 From: Hu Tao Date: Wed, 10 Sep 2014 17:05:48 +0800 Subject: raw-posix: Add falloc and full preallocation option This patch adds a new option preallocation for raw format, and implements falloc and full preallocation. Signed-off-by: Hu Tao Reviewed-by: Max Reitz Signed-off-by: Kevin Wolf --- qemu-img.texi | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'qemu-img.texi') diff --git a/qemu-img.texi b/qemu-img.texi index cc4668e64f..d64d05edda 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -419,6 +419,15 @@ Linux or NTFS on Windows), then only the written sectors will reserve space. Use @code{qemu-img info} to know the real size used by the image or @code{ls -ls} on Unix/Linux. +Supported options: +@table @code +@item preallocation +Preallocation mode (allowed values: @code{off}, @code{falloc}, @code{full}). +@code{falloc} mode preallocates space for image by calling posix_fallocate(). +@code{full} mode preallocates space for image by writing zeros to underlying +storage. +@end table + @item qcow2 QEMU image format, the most versatile format. Use it to have smaller images (useful if your filesystem does not supports holes, for example -- cgit v1.2.3