Btrfs device related fixes to support new features and bug fixes

Hi David,

Please consider the following fixes for your integration. These patches provide bug fixes, framework changes to support new features, and 3 new features. They are mainly related to the device management like delete device by devid, introduce sysfs for device and pool, and fix the fs logging for multiple devices. All these patches has been sent to the mailing list as individual patches before.

https://github.com/asj/btrfs-devel.git for-dave4

(please note, the change log and subject line for some of the patches may contain minor updates).

Anand Jain (16):
btrfs: Pass the error code to the btrfs_std_error and log ret
btrfs: Create a helper function to read the disk super
btrfs: Maintain consistency in logging to help debugging
btrfs: Device path change must be logged
btrfs: Add missing brelse when superblock checksum fails
btrfs: sysfs: Support seed devices in the sysfs layout
btrfs: Create a framework to create pool attributes
btrfs: Create helper function __check_raid_min_devices()
btrfs: Clean up and optimize __check_raid_min_device()
btrfs: Create helper btrfs_find_device_by_user_input()
btrfs: Make use of btrfs_find_device_by_user_input()
btrfs: Enhance btrfs_find_device_by_user_input() to check device path
btrfs: Make use of btrfs_scratch_superblocks() in btrfs_rm_device()
btrfs: Introduce device delete by devid
btrfs: Introduce device pool sysfs attributes
btrfs: Fix fs logging for multi device

 fs/btrfs/dev-replace.c     |  41 +--
 fs/btrfs/disk-io.c         |  23 +-
 fs/btrfs/ioctl.c           |  65 ++++-
 fs/btrfs/super.c           |   4 +-
 fs/btrfs/sysfs.c           | 624 
++++++++++++++++++++++++++++++++++++++++++++-
 fs/btrfs/sysfs.h           |  21 +-
 fs/btrfs/volumes.c         | 385 ++++++++++++++--------------
 fs/btrfs/volumes.h         |  16 +-
 include/uapi/linux/btrfs.h |  14 +-
 9 files changed, 937 insertions(+), 256 deletions(-)