Add pure python EDD code parsing and compareDrives substitute (#478996)

There are various issues with the EDD C-code, mostly that it is way
too complicated for what it does. This patch re-implements it in
python, and adds a compareDrives substitute to the storage class.

Note that the compareDrives substitute is a copy and paste job of the
isys code (using the new storage edd_dict). The isys code will be removed
in a separate patch.

2 files changed, 152 insertions, 0 deletions

diff --git a/storage/__init__.py b/storage/__init__.py
index 4c026dc77..91a75de78 100644
--- a/storage/__init__.py
+++ b/storage/__init__.py
@@ -48,6 +48,7 @@ from devicelibs.lvm import safeLvmName
 from devicelibs.dm import name_from_dm_node
 from devicelibs.crypto import generateBackupPassphrase
 from devicelibs.mpath import MultipathConfigWriter
+from devicelibs.edd import get_edd_dict
 from udev import *
 import iscsi
 import fcoe
@@ -255,6 +256,7 @@ class Storage(object):
         self.zeroMbr = None
         self.protectedDevSpecs = []
         self.autoPartitionRequests = []
+        self.eddDict = {}
 
         self.__luksDevs = {}
 
@@ -373,6 +375,7 @@ class Storage(object):
                                      dasd=self.dasd)
         self.devicetree.populate()
         self.fsset = FSSet(self.devicetree, self.anaconda.rootPath)
+        self.eddDict = get_edd_dict(self.partitioned)
         self.anaconda.id.rootParts = None
         self.anaconda.id.upgradeRoot = None
         self.dumpState("initial")
@@ -1163,6 +1166,58 @@ class Storage(object):
     def rootDevice(self):
         return self.fsset.rootDevice
 
+    def compareDisks(self, first, second):
+        if self.eddDict.has_key(first) and self.eddDict.has_key(second):
+            one = self.eddDict[first]
+            two = self.eddDict[second]
+            if (one < two):
+                return -1
+            elif (one > two):
+                return 1
+
+        # if one is in the BIOS and the other not prefer the one in the BIOS
+        if self.eddDict.has_key(first):
+            return -1
+        if self.eddDict.has_key(second):
+            return 1
+
+        if first.startswith("hd"):
+            type1 = 0
+        elif first.startswith("sd"):
+            type1 = 1
+        elif (first.startswith("vd") or first.startswith("xvd")):
+            type1 = -1
+        else:
+            type1 = 2
+
+        if second.startswith("hd"):
+            type2 = 0
+        elif second.startswith("sd"):
+            type2 = 1
+        elif (second.startswith("vd") or second.startswith("xvd")):
+            type2 = -1
+        else:
+            type2 = 2
+
+        if (type1 < type2):
+            return -1
+        elif (type1 > type2):
+            return 1
+        else:
+            len1 = len(first)
+            len2 = len(second)
+
+            if (len1 < len2):
+                return -1
+            elif (len1 > len2):
+                return 1
+            else:
+                if (first < second):
+                    return -1
+                elif (first > second):
+                    return 1
+
+        return 0
 
 def getReleaseString(mountpoint):
     relName = None
diff --git a/storage/devicelibs/edd.py b/storage/devicelibs/edd.py
new file mode 100644
index 000000000..da0391437
--- /dev/null
+++ b/storage/devicelibs/edd.py
@@ -0,0 +1,97 @@
+#
+# edd.py
+# BIOS EDD data parsing functions
+#
+# Copyright (C) 2010  Red Hat, Inc.  All rights reserved.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Author(s): Hans de Goede <hdegoede@redhat.com>
+#
+
+import os
+import struct
+
+import logging
+log = logging.getLogger("storage")
+
+def get_edd_dict(devices):
+    """Given an array of devices return a dict with the BIOS ID for them."""
+    edd_dict = {}
+
+    for biosdev in range(80, 80 + 15):
+        sysfspath = "/sys/firmware/edd/int13_dev%d" % biosdev
+        if not os.path.exists(sysfspath):
+            break # We are done
+
+        sysfspath = "/sys/firmware/edd/int13_dev%d/mbr_signature" % biosdev
+        if not os.path.exists(sysfspath):
+            log.warning("No mbrsig for biosdev: %d" % biosdev)
+            continue
+
+        try:
+            file = open(sysfspath, "r")
+            eddsig = file.read()
+            file.close()
+        except (IOError, OSError) as e:
+            log.warning("Error reading EDD mbrsig for %d: %s" %
+                        (biosdev, str(e)))
+            continue
+
+        sysfspath = "/sys/firmware/edd/int13_dev%d/sectors" % biosdev
+        try:
+            file = open(sysfspath, "r")
+            eddsize = file.read()
+            file.close()
+        except (IOError, OSError) as e:
+            eddsize = None
+
+        found = []
+        for dev in devices:
+            try:
+                fd = os.open(dev.path, os.O_RDONLY)
+                os.lseek(fd, 440, 0) 
+                mbrsig = struct.unpack('I', os.read(fd, 4))
+                os.close(fd)
+            except OSError as e:
+                log.warning("Error reading mbrsig from disk %s: %s" %
+                            (dev.name, str(e)))
+                continue
+
+            mbrsigStr = "0x%08x\n" % mbrsig
+            if mbrsigStr == eddsig:
+                if eddsize:
+                    sysfspath = "/sys%s/size" % dev.sysfsPath
+                    try:
+                        file = open(sysfspath, "r")
+                        size = file.read()
+                        file.close()
+                    except (IOError, OSError) as e:
+                        log.warning("Error getting size for: %s" % dev.name)
+                        continue
+                    if eddsize != size:
+                        continue
+                found.append(dev.name)
+
+        if not found:
+            log.error("No matching mbr signature found for biosdev %d" %
+                      biosdev)
+        elif len(found) > 1:
+            log.error("Multiple signature matches found for biosdev %d: %s" %
+                      (biosdev, str(found)))
+        else:
+            log.info("Found %s for biosdev %d" %(found[0], biosdev))
+            edd_dict[found[0]] = biosdev
+
+    return edd_dict