02/04: syscalls: 'device-in-use?' returns #f upon EINVAL.

[guix-commits]

civodul pushed a commit to branch wip-newt-installer
in repository guix.

commit 048976a02502679449258992925489933c7e5edd
Author: Ludovic Courtès <address@hidden>
Date:   Wed Jan 16 17:43:52 2019 +0100

    syscalls: 'device-in-use?' returns #f upon EINVAL.
    
    This mirrors the behavior of the 'fdisk_device_is_used' function of
    util-linux.
    
    * guix/build/syscalls.scm (device-in-use?): Return #f upon EINVAL.
---
 guix/build/syscalls.scm | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/guix/build/syscalls.scm b/guix/build/syscalls.scm
index 59cc270..26ab5e7 100644
--- a/guix/build/syscalls.scm
+++ b/guix/build/syscalls.scm
@@ -701,6 +701,11 @@ backend device."
       #f)
      ((= err EBUSY)
       #t)
+     ((= err EINVAL)
+      ;; We get EINVAL for devices that have the GENHD_FL_NO_PART_SCAN flag
+      ;; set in the kernel, in particular loopback devices, though we do seem
+      ;; to get it for SCSI storage (/dev/sr0) on QEMU.
+      #f)
      (else
       (throw 'system-error "ioctl" "~A"
              (list (strerror err))