[PATCH 0/5 v5] access to backup-sb and btrfs' multipath aware

[Anand Jain <anand.jain@oracle.com>]

We need a mechanism to tell when to use the backup super_block.
To do this it needs a frame-work, and the patch #2 and #3 below
provides the same without change in the logic.

Its been found and posted to the list that check_mounted needs
access to the backup-sb. so patch #3 adds flags parameter
to the function btrfs_scan_one_device so that _only_
check_mounted can set the flag to access the backup-sb. 

patch#4 below is to enable and disable acecss to backup-sb
for only certain threads

v4->v5:
	Rebase with integration-20130321 and with my own changes (patch #1)
	Allow check_mounted thread-path to use backup-sb

v3->v4:
	Fixed some warnings introduced by patch #3 below,
	sorry my mistake.

v2->v3:
        Accepts David and Eric review, which would result in disabled
          access to backup-superblock by default.
        Dropped the patch
                [PATCH 3/3] btrfs-progs: use BTRFS_SCAN_BACKUP_SB flag in btrfs_scan_one_device
        Introduced a new patch
                [PATCH 3/3] btrfs-progs: disable using backup superblock by default

v1->v2:
        Accepts Eric and Zach review.
        Separates fix into 3 patches for easy logical understanding

Anand Jain (5):
  btrfs-progs: make btrfs dev scan multi path aware
  btrfs-progs: Introduce flag BTRFS_SCAN_REGISTER to replace run_ioctl
  btrfs-progs: Introduce flag BTRFS_SCAN_BACKUP_SB for
    btrfs_read_dev_super
  btrfs-progs: introduce passing flags to btrfs_scan_one_device
  btrfs-progs: disable using backup superblock by default

 cmds-device.c  | 57 +++++++++++++++++++++++++++++++++++++++++----------------
 cmds-replace.c |  2 +-
 disk-io.c      | 15 ++++++++++-----
 disk-io.h      |  3 ++-
 find-root.c    |  9 ++++++---
 utils.c        | 57 +++++++++++++++++++++++++++++++++++++++------------------
 utils.h        |  8 +++++---
 volumes.c      |  6 ++++--
 volumes.h      |  2 +-
 9 files changed, 109 insertions(+), 50 deletions(-)

-- 
1.8.1.227.g44fe835