Re: [libvirt] [PATCH 03/11] storage: Add partition type checks for BLKID probing

A device may be formatted using some sort of disk partition format type. We can check that using the blkid_ API's as well - so alter the logic to allow checking the device for both a filesystem and a disk partition. Signed-off-by: John Ferlan <jferlan(a)redhat.com&gt; --- src/storage/storage_backend.c | 177 ++++++++++++++++++++++++++++++++---------- 1 file changed, 138 insertions(+), 39 deletions(-) diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c index 108f2b9..065f2ef 100644 --- a/src/storage/storage_backend.c +++ b/src/storage/storage_backend.c @@ -2639,37 +2639,117 @@ virStorageBackendFindGlusterPoolSources(const char *host ATTRIBUTE_UNUSED, #if WITH_BLKID + +typedef enum { + VIR_STORAGE_BLKID_PROBE_ERROR = -1, + VIR_STORAGE_BLKID_PROBE_UNDEFINED, /* Nothing found */ + VIR_STORAGE_BLKID_PROBE_UNKNOWN, /* Don't know libvirt fs/part type */ + VIR_STORAGE_BLKID_PROBE_MATCH, /* Matches the on disk format */ + VIR_STORAGE_BLKID_PROBE_DIFFERENT, /* Format doesn't match on disk format */ +} virStorageBackendBLKIDProbeResult; + +/* + * Utility function to probe for a file system on the device using the + * blkid "superblock" (e.g. default) APIs. + * + * NB: In general this helper will handle the virStoragePoolFormatFileSystem + * format types; however, if called from the Disk path, the initial fstype + * check will fail forcing the usage of the ProbePart helper. + * + * Returns virStorageBackendBLKIDProbeResult enum + */ +static virStorageBackendBLKIDProbeResult +virStorageBackendBLKIDProbeFS(blkid_probe probe, + const char *device, + const char *format) +{ + const char *fstype = NULL; + + /* Make sure we're doing a superblock probe from the start */ + blkid_probe_enable_superblocks(probe, true); + blkid_probe_reset_superblocks_filter(probe); + + if (blkid_do_probe(probe) != 0) { + VIR_INFO("No filesystem found on device '%s'", device); + return VIR_STORAGE_BLKID_PROBE_UNDEFINED; + } + + if (blkid_probe_lookup_value(probe, "TYPE", &fstype, NULL) == 0) { + if (STREQ(fstype, format)) + return VIR_STORAGE_BLKID_PROBE_MATCH; + + return VIR_STORAGE_BLKID_PROBE_DIFFERENT; + } + + if (blkid_known_fstype(format) == 0) + return VIR_STORAGE_BLKID_PROBE_UNKNOWN; + + return VIR_STORAGE_BLKID_PROBE_ERROR; +}