Re: [libvirt] [PATCH v4 2/2] storage: Improve error handling on cdrom backend
On 10/25/18 11:39 PM, Han Han wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=1596096
Implement virFileCheckCDROM in virStorageBackendVolOpen to check if
cdrom backend is ok. Report more detailed error if not ok.
Signed-off-by: Han Han <hhan(a)redhat.com>
---
src/storage/storage_util.c | 32 ++++++++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/src/storage/storage_util.c b/src/storage/storage_util.c
index 318a556656..c9f89b817a 100644
--- a/src/storage/storage_util.c
+++ b/src/storage/storage_util.c
@@ -1601,6 +1601,38 @@ virStorageBackendVolOpen(const char *path, struct stat *sb,
return -1;
}
+#if defined(__linux__)
This not what I was expecting... Let's not have conditionals in this
module and go with my suggestion from patch1 of changing the non linux
version of virFileCheckCDROM to return VIR_FILE_CDROM_DISC_OK when we
return 1 and to return/handle VIR_FILE_CDROM_NO_DEVICE here when 0 is
returned (even though this code doesn't handle that "yet").
+ virFileCDRomStatus cd_status = VIR_FILE_CDROM_UNKNOWN;
Definition belongs at the top-level...
+
+ if (virFileCheckCDROM(path, &cd_status) > 0) {
+ switch (cd_status) {
+ case VIR_FILE_CDROM_UNKNOWN:
+ virReportError(VIR_ERR_NO_STORAGE_VOL,
+ _("unknown status for CDROM storage vol
'%s'"),
+ path);
+ return -1;
+ case VIR_FILE_CDROM_NO_DISC:
+ virReportError(VIR_ERR_NO_STORAGE_VOL,
+ _("no disc in CDROM storage vol
'%s'"),
+ path);
+ return -1;
+ case VIR_FILE_CDROM_TRAY_OPEN:
+ virReportError(VIR_ERR_NO_STORAGE_VOL,
+ _("the tray of CDROM storage vol '%s' is
open"),
+ path);
+ return -1;
+ case VIR_FILE_CDROM_DRIVE_NOT_READY:
+ virReportError(VIR_ERR_NO_STORAGE_VOL,
+ _("CDROM storage vol '%s' is not
ready"),
+ path);
+ return -1;
+ case VIR_FILE_CDROM_DISC_OK:
+ VIR_INFO("CDROM storage vol %s is OK", path);
Depending on the level of debugging enabled and the times we go through
here, this could be chatty...
Also, kind of strange to be making a check for a specific issue from the
bz description in a generic place. Check all the callers of
virStorageBackendVolOpen... I think you may need to move this switch.
For callers that may be correctly supplying a CDROM @path we could
return a failure now.
The switch may be nice as a common/shared method too so that no one is
tempted to cut-n-paste whenever the values are needed.
John
+ break;
+ }
+ }
+#endif /* defined(__linux__) */
+
/* O_NONBLOCK should only matter during open() for fifos and
* sockets, which we already filtered; but using it prevents a
* TOCTTOU race. However, later on we will want to read() the