btrfs-progs: clarify mkfs.btrfs --alloc-start option
PATCH 1/1 btrfs-progs: clarify mkfs.btrfs --alloc-start option
Fedora had a bug where a poor user thought that --alloc-start meant that the filesystem would be created at that offset into the device, rather than just starting allocations at that offset. A subtle difference, but worth clarifying, because the manpage is misleading on this point.
The original commit log for this option says:
Add mkfs.btrfs -A offset to control allocation start on devices
This is a utility option for the resizer, it makes sure to allocate at offset bytes in the disk or higher. It ensures the resizer will have something to move when testing it.
so allude to that intended use in the manpage.
Signed-off-by Eric Sandeen <[email protected]>
---
man/mkfs.btrfs.8.in +1 -1
@@ -30,7 +30,7 @@ spanning across the specified \fI devices\fP. .SH OPTIONS .TP \fB\-A\fR, \fB\-\-alloc\-start \fIoffset\fR -Specify the offset from the start of the device to start the btrfs filesystem. The default value is zero, or the start of the device. +Specify the offset from the start of the device at which to start allocations in this btrfs filesystem. The default value is zero, or the start of the device. This option is intended only for debugging filesystem resize operations. .TP \fB\-b\fR, \fB\-\-byte\-count \fIsize\fR Specify the size of the resultant filesystem. If this option is not used,