diff options
Diffstat (limited to 'myraid.py')
| -rw-r--r-- | myraid.py | 141 |
1 files changed, 17 insertions, 124 deletions
@@ -18,57 +18,14 @@ # You should have received a copy of the GNU General Public License # along with RaidGuessFS. If not, see <http://www.gnu.org/licenses/> -import logging, numpy -import mydisks +import logging +from myraidmaths import MyRaidMaths class MyRaid(): """Auxiliary class, managing RAID layer""" RAID_TYPES = [ '0', '1', '5', '5+0' ] RAID5_LAYOUTS = [ 'la', 'ra', 'ls', 'rs' ] - @staticmethod - def xor_blocks(fd_list, offset, size): - """Compute bitwise XOR against a bunch of disks slice""" - logging.info("Enter xor_blocks(fd_list(%i),0x%011x,%d)"%(len(fd_list), offset, size)) - - if size % 8 != 0: - raise ValueError('xor_blocks : size must be multiple of 8') - dt = numpy.dtype('<Q8') - - fd_list[0].seek(offset) - str_b1=fd_list[0].read(size) - numpy_b1 = numpy.fromstring(str_b1, dtype=dt) - all_zero = (numpy.count_nonzero(numpy_b1) == 0 ) - any_zero = all_zero - - for fd in fd_list[1:]: - fd.seek(offset) - str_b2=fd.read(size) - numpy_b2 = numpy.fromstring(str_b2, dtype=dt) - b2_zero = (numpy.count_nonzero(numpy_b2) == 0 ) - if all_zero == True: - all_zero = b2_zero - if any_zero == False: - any_zero = b2_zero - - numpy.bitwise_xor(numpy_b1,numpy_b2,numpy_b1) - - if all_zero == True: - result = 'z' - elif numpy.count_nonzero(numpy_b1) == 0: - if any_zero: - result = 'g' - else: - result = 'G' - else: - result = 'b' - - logging.info("Exit. xor_blocks(fd_list,%d,%d)"%(offset, size)) - #import binascii - #logging.debug(binascii.hexlify(numpy_b1)) - return (result,numpy_b1) - - def __init__(self, *args, **kwargs): self.d = None self.raid_start = 0 @@ -161,7 +118,7 @@ class MyRaid(): def read_disk_xor(self,raid_type,offset,size): """Returns raw bitwise XOR against a bunch of disks slice""" - return MyRaid.xor_blocks(self.raid_disks,offset,size)[1].tostring() + return MyRaidMaths.xor_blocks(self.raid_disks,offset,size)[1] def read_disk_parity(self,raid_type,offset,size): """Returns textual information about parity status of each sector""" @@ -182,7 +139,7 @@ class MyRaid(): #TODO : improove for nested levels if raid_type in ['1','5', '5+0']: result = ''.join( - [ '0x%011x %c\n'%( addr, MyRaid.xor_blocks(self.raid_disks, addr, self.raid_sector_size)[0]) + [ '0x%011x %c\n'%( addr, MyRaidMaths.xor_blocks(self.raid_disks, addr, self.raid_sector_size)[0]) for addr in xrange(start, end, self.raid_sector_size) ]) else: @@ -194,87 +151,22 @@ class MyRaid(): def read_raid_result(self,raid_type,offset,size): """Returns actual RAID data""" - if raid_type == '0': - segment_no = offset / self.raid_chunk_size - segment_off = offset % self.raid_chunk_size - stripe_no = segment_no / self.raid_disk_count - subraid_no = -1 - par_disk = -1 - data_disk = segment_no % self.raid_disk_count - off_disk = self.raid_start + stripe_no * self.raid_chunk_size + segment_off - size2 = min(size, (segment_no+1) * self.raid_chunk_size - offset) - - elif raid_type == '1': - segment_no = -1 - segment_off = -1 - stripe_no = -1 - subraid_no = -1 - par_disk = 1 - data_disk = 0 - off_disk = self.raid_start + offset - size2 = size - - elif raid_type == '5': - segment_no = offset / self.raid_chunk_size - segment_off = offset % self.raid_chunk_size - stripe_no = segment_no / (self.raid_disk_count-1) - subraid_no = -1 - - if self.raid_layout in ['ls','la']: - par_disk = (self.raid_disk_count-1) - (stripe_no % self.raid_disk_count) - else: # self.raid_layout in ['rs','ra']: - par_disk = stripe_no % self.raid_disk_count - - if self.raid_layout in ['ls','rs']: - data_disk = (par_disk+1 + (segment_no % (self.raid_disk_count-1)) ) % self.raid_disk_count - else: # self.raid_layout in ['la','ra']: - data_disk = segment_no % (self.raid_disk_count-1) - if data_disk >= par_disk: - data_disk = data_disk + 1 - - off_disk = self.raid_start + stripe_no * self.raid_chunk_size + segment_off - # Note : could make error-free shorter reads than asked but convince the reader to be chunck aligned, which is great for perf - size2 = min(size, (segment_no+1) * self.raid_chunk_size - offset) - - elif raid_type == '5+0': - subraid_disk_count = self.raid_disk_count / self.nested_subraid - segment_no = offset / self.raid_chunk_size - segment_off = offset % self.raid_chunk_size - stripe_no = segment_no / (self.raid_disk_count - self.nested_subraid) # segment_no / 12 - subraid_no = (segment_no / (subraid_disk_count-1) ) % self.nested_subraid # (segment_no/6) mod 2 - - if self.raid_layout in ['ls','la']: - subraid_par_disk = (subraid_disk_count-1) - (stripe_no % subraid_disk_count) - else: # self.raid_layout in ['rs','ra']: - subraid_par_disk = stripe_no % subraid_disk_count - - if self.raid_layout in ['ls','rs']: - subraid_data_disk = (subraid_par_disk+1 + (segment_no % (subraid_disk_count-1)) ) % subraid_disk_count - else: # self.raid_layout in ['la','ra']: - subraid_data_disk = segment_no % (subraid_disk_count-1) - if subraid_data_disk >= subraid_par_disk: - subraid_data_disk = subraid_data_disk + 1 - - par_disk = subraid_no * subraid_disk_count + subraid_par_disk - data_disk = subraid_no * subraid_disk_count + subraid_data_disk - - off_disk = self.raid_start + stripe_no * self.raid_chunk_size + segment_off - # Note : could make error-free shorter reads than asked but convince the reader to be chunck aligned, which is great for perf - size2 = min(size, (segment_no+1) * self.raid_chunk_size - offset) + res = MyRaidMaths.apply_raid_layout(offset, size, raid_type, self.raid_layout, self.raid_chunk_size, self.raid_disk_count, self.raid_start, self.nested_subraid); + + (segment_no, segment_off, stripe_no, subraid_no, par_disk, data_disk, off_disk, aligned_read_size) = res - else: - raise Exception('Unimplemented read_raid_result() for raid_type == %s', raid_type) - logging.debug("raid.read_result(%s): offset=%d,segment_no=%d,segment_off=%d,stripe_no=%d,subraid_no=%d,par_disk=%d(disk%02d),data_disk=%d(disk%02d),off_disk=%d,size2=%d,segment_off+size2=%d" - % (raid_type,offset,segment_no,segment_off,stripe_no,subraid_no,par_disk,self.raid_disk_order[par_disk],data_disk,self.raid_disk_order[data_disk],off_disk,size2,segment_off+size2) ) + logging.debug("raid.read_result(%s): offset=%d,segment_no=%d,segment_off=%d,stripe_no=%d,subraid_no=%d,par_disk=%d(disk%02d),data_disk=%d(disk%02d),off_disk=%d,aligned_read_size=%d,segment_off+aligned_read_size=%d" + % (raid_type,offset,segment_no,segment_off,stripe_no,subraid_no,par_disk,self.raid_disk_order[par_disk],data_disk,self.raid_disk_order[data_disk],off_disk,aligned_read_size,segment_off+aligned_read_size) ) data_fd = self.raid_disks[data_disk] - if self.d.is_readable(self.raid_disk_order[data_disk],off_disk,size2): + if self.d.is_readable(self.raid_disk_order[data_disk],off_disk,aligned_read_size): # No damaged sectors until the end of the chunck, so just read the data disk data_fd.seek(off_disk) - data = data_fd.read(size2) + data = data_fd.read(aligned_read_size) else: + # TODO : this is only for RAID5 logging.warn('Try to recovering damaged chunck (raid_offset: 0x%011x, data_disk: %i, disk_offset: 0x%011x' % (offset, self.raid_disk_order[data_disk], off_disk) ) # Damaged sectors, check / recover every sector @@ -284,7 +176,7 @@ class MyRaid(): other_fds.remove(data_fd) data_arr = [] - for s in xrange(off_disk, off_disk+size2, self.raid_sector_size): + for s in xrange(off_disk, off_disk+aligned_read_size, self.raid_sector_size): if self.d.is_readable(self.raid_disk_order[data_disk],s,self.raid_sector_size): # Current sector is readable from data disk, read it logging.debug('-> 0x%011x : readable'%s) @@ -297,15 +189,16 @@ class MyRaid(): ]) if recoverable: logging.info('-> 0x%011x : recoverable'%s) - data_arr.append( MyRaid.xor_blocks(other_fds, s,self.raid_sector_size)[1].tostring() ) + data_arr.append( MyRaidMaths.xor_blocks(other_fds, s,self.raid_sector_size)[1] ) else: logging.warn('-> 0x%011x : unrecoverable'%s) data_arr.append( '\0' * self.raid_sector_size) data = ''.join(data_arr) # Prevent short reads, seems mandatory for losetup'ing raid_result but kills performance - if size2 < size: - return ''.join( (data, self.read_raid_result(raid_type,offset+size2,size-size2) ) ) + #TODO : make it activable per config + if aligned_read_size < size: + return ''.join( (data, self.read_raid_result(raid_type,offset+aligned_read_size,size-aligned_read_size) ) ) return data |