Make our edd matcher able to use a fake sysfs root.

Signed-off-by: Peter Jones <pjones@redhat.com>

blivet/devicelibs/edd.py

@@ -58,6 +58,8 @@
 # anchoring tab that would go between them...
 re_interface_unknown = re.compile(r'^(\S*)\s*unknown: (\S*) (\S*)\s*$')
 
+fsroot = ""
+
 class EddEntry(object):
     """ This object merely collects what the /sys/firmware/edd/* entries can
         provide.
@@ -300,12 +302,12 @@ def __init__(self, edd_entry):
         self.edd = edd_entry
 
     def devname_from_ata_pci_dev(self):
-        pattern = '/sys/block/*'
+        pattern = '%s/sys/block/*' % (fsroot,)
         for path in glob.iglob(pattern):
             link = os.readlink(path)
             # just add /sys/block/ at the beginning so it's always valid
             # paths in the filesystem...
-            components = ['/sys/block'] + link.split('/')
+            components = ['%s/sys/block' % (fsroot,)] + link.split('/')
             if len(components) != 11:
                 continue
             # ATA and SATA paths look like:
@@ -370,18 +372,19 @@ def devname_from_ata_pci_dev(self):
                     if (self.edd.channel == 255 and channel == 0) or \
                             (self.edd.channel == channel):
                         self.edd.sysfslink = link
-                        return path.split('/')[-1]
+                        return path[len(fsroot):].split('/')[-1]
                 else:
                     pmp = int(match.group(1))
                     if self.edd.ata_pmp == pmp:
                         self.edd.sysfslink = link
-                        return path.split('/')[-1]
+                        return path[len(fsroot):].split('/')[-1]
         return None
 
     def devname_from_scsi_pci_dev(self):
         name = None
-        path = "/sys/devices/pci0000:00/0000:%(pci_dev)s/host%(chan)d/"\
+        path = "%(fsroot)s/sys/devices/pci0000:00/0000:%(pci_dev)s/host%(chan)d/"\
             "target%(chan)d:0:%(dev)d/%(chan)d:0:%(dev)d:%(lun)d/block" % {
+            'fsroot' : fsroot,
             'pci_dev' : self.edd.pci_dev,
             'chan' : self.edd.channel,
             'dev' : self.edd.scsi_id,
@@ -398,8 +401,10 @@ def devname_from_scsi_pci_dev(self):
 
     def devname_from_virt_pci_dev(self):
         name = None
-        pattern = "/sys/devices/pci0000:00/0000:%(pci_dev)s/virtio*/block" % \
-            {'pci_dev' : self.edd.pci_dev}
+        pattern = "%(fsroot)s/sys/devices/pci0000:00/0000:%(pci_dev)s/virtio*/block" % {
+            'fsroot' : fsroot,
+            'pci_dev' : self.edd.pci_dev
+            }
         matching_paths = glob.glob(pattern)
         if len(matching_paths) != 1 or not os.path.exists(matching_paths[0]):
             return None
@@ -438,7 +443,10 @@ def match_via_mbrsigs(self, mbr_dict):
         return None
 
 def biosdev_to_edd_dir(biosdev):
-    return "/sys/firmware/edd/int13_dev%x" % biosdev
+    return "%(fsroot)s/sys/firmware/edd/int13_dev%(biosdev)x" % {
+        'fsroot' : fsroot,
+        'biosdev' : biosdev
+        }
 
 def collect_edd_data():
     edd_data_dict = {}
@@ -462,7 +470,9 @@ def collect_mbrs(devices):
     mbr_dict = {}
     for dev in devices:
         try:
-            fd = util.eintr_retry_call(os.open, dev.path, os.O_RDONLY)
+            path = dev.name.split('/')
+            path = os.path.join(fsroot, *path)
+            fd = util.eintr_retry_call(os.open, path, os.O_RDONLY)
             # The signature is the unsigned integer at byte 440:
             os.lseek(fd, 440, 0)
             mbrsig = struct.unpack('I', util.eintr_retry_call(os.read, fd, 4))