linux/drivers/md
Dan Ehrenberg 644bda6f34 dm table: fall back to getting device using name_to_dev_t()
If a device is used as the root filesystem, it can't be built
off of devices which are within the root filesystem (just like
command line arguments to root=).  For this reason, Linux has a
pseudo-filesystem for root= and MD initialization (based on the
function name_to_dev_t) which handles different ways of specifying
devices including PARTUUID and major:minor.

Switch to using name_to_dev_t() in dm_get_device().  Rather than
having DM assume that all things which are not major:minor are paths in
an already-mounted filesystem, change dm_get_device() to first attempt
to look up the device in the filesystem, and if not found it will fall
back to using name_to_dev_t().

In terms of backwards compatibility, there are some cases where
behavior will be different:
- If you have a file in the current working directory named 1:2 and
  you initialze DM there, then it will try to use that file rather
  than the disk with that major:minor pair as a backing device.
- Similarly for other bdev types which name_to_dev_t() knows how to
  interpret, the previous behavior was to repeatedly check for the
  existence of the file (e.g., while waiting for rootfs to come up)
  but the new behavior is to use the name_to_dev_t() interpretation.
  For example, if you have a file named /dev/ubiblock0_0 which is
  a symlink to /dev/sda3, but it is not yet present when DM starts
  to initialize, then the name_to_dev_t() interpretation will take
  precedence.

These incompatibilities would only show up in really strange setups
with bad practices so we shouldn't have to worry about them.

Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2015-04-15 12:10:19 -04:00
..
bcache md/bcache: use generic io stats accounting functions to simplify io stat accounting 2014-11-24 08:05:12 -07:00
persistent-data - Significant dm-crypt CPU scalability performance improvements thanks 2015-02-21 13:28:45 -08:00
bitmap.c md: remove mddev_lock() from md_attr_show() 2015-02-06 09:32:55 +11:00
bitmap.h kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly 2013-12-11 15:28:36 -08:00
dm-bio-prison.c dm bio prison: introduce support for locking ranges of blocks 2014-11-10 15:25:30 -05:00
dm-bio-prison.h dm bio prison: introduce support for locking ranges of blocks 2014-11-10 15:25:30 -05:00
dm-bio-record.h dm: Refactor for new bio cloning/splitting 2013-11-23 22:33:55 -08:00
dm-bufio.c dm bufio: fix time comparison to use time_after_eq() 2015-02-09 13:06:48 -05:00
dm-bufio.h dm snapshot: use dm-bufio prefetch 2014-01-14 23:23:03 -05:00
dm-builtin.c dm sysfs: fix a module unload race 2014-01-14 23:23:04 -05:00
dm-cache-block-types.h dm cache: revert "remove remainder of distinct discard block size" 2014-11-10 15:25:30 -05:00
dm-cache-metadata.c dm cache: fix missing ERR_PTR returns and handling 2015-01-28 09:59:20 -05:00
dm-cache-metadata.h dm cache: revert "remove remainder of distinct discard block size" 2014-11-10 15:25:30 -05:00
dm-cache-policy-cleaner.c dm cache: policy change version from string to integer set 2013-03-20 17:21:27 +00:00
dm-cache-policy-internal.h dm cache: add remove_cblock method to policy interface 2013-11-11 11:37:50 -05:00
dm-cache-policy-mq.c dm cache policy mq: try not to writeback data that changed in the last second 2015-03-31 12:03:48 -04:00
dm-cache-policy.c dm cache: add policy name to status output 2014-01-16 13:44:11 -05:00
dm-cache-policy.h dm cache: add policy name to status output 2014-01-16 13:44:11 -05:00
dm-cache-target.c - Most significant change this cycle is request-based DM now supports 2015-02-12 16:36:31 -08:00
dm-crypt.c dm crypt: sort writes 2015-02-16 11:11:15 -05:00
dm-delay.c Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
dm-era-target.c dm era: check for a non-NULL metadata object before closing it 2014-06-03 13:44:08 -04:00
dm-exception-store.c dm: replace simple_strtoul 2012-07-27 15:07:59 +01:00
dm-exception-store.h dm snapshot: test chunk size against both origin and snapshot 2010-08-12 04:13:51 +01:00
dm-flakey.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
dm-io.c dm io: deal with wandering queue limits when handling REQ_DISCARD and REQ_WRITE_SAME 2015-02-27 14:53:32 -05:00
dm-ioctl.c dm ioctl: fix stale comment above dm_get_inactive_table() 2015-02-09 13:06:48 -05:00
dm-kcopyd.c dm: stop using WQ_NON_REENTRANT 2013-08-23 09:02:13 -04:00
dm-linear.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
dm-log-userspace-base.c dm log userspace: split flush_entry_pool to be per dirty-log 2015-03-31 12:03:47 -04:00
dm-log-userspace-transfer.c dm log userspace: fix memory leak in dm_ulog_tfr_init failure path 2014-10-05 20:03:38 -04:00
dm-log-userspace-transfer.h dm log: userspace add luid to distinguish between concurrent log instances 2009-09-04 20:40:34 +01:00
dm-log.c dm: use memweight() 2012-07-30 17:25:16 -07:00
dm-mpath.c dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq 2015-04-15 12:10:17 -04:00
dm-mpath.h
dm-path-selector.c md: Add module.h to all files using it implicitly 2011-10-31 19:31:18 -04:00
dm-path-selector.h dm mpath: add start_io and nr_bytes to path selectors 2009-06-22 10:12:27 +01:00
dm-queue-length.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-raid1.c dm mirror: do not degrade the mirror on discard error 2015-02-13 19:50:46 -05:00
dm-raid.c - Most significant change this cycle is request-based DM now supports 2015-02-12 16:36:31 -08:00
dm-region-hash.c block: Abstract out bvec iterator 2013-11-23 22:33:47 -08:00
dm-round-robin.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-service-time.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-snap-persistent.c dm snapshot: remove unnecessary NULL checks before vfree() calls 2015-02-09 13:06:49 -05:00
dm-snap-transient.c md: Add in export.h for files using EXPORT_SYMBOL 2011-10-31 19:31:19 -04:00
dm-snap.c dm snapshot: suspend merging snapshot when doing exception handover 2015-02-27 14:53:16 -05:00
dm-stats.c - Significant DM thin-provisioning performance improvements to meet 2014-12-08 21:10:03 -08:00
dm-stats.h dm: add statistics support 2013-09-05 20:46:06 -04:00
dm-stripe.c dm stripe: fix potential for leak in stripe_ctr error path 2014-10-10 22:05:18 -04:00
dm-switch.c dm switch: efficiently support repetitive patterns 2014-08-01 12:30:37 -04:00
dm-sysfs.c dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
dm-table.c dm table: fall back to getting device using name_to_dev_t() 2015-04-15 12:10:19 -04:00
dm-target.c dm: allocate requests in target when stacking on blk-mq devices 2015-02-09 13:06:47 -05:00
dm-thin-metadata.c dm thin metadata: remove unused dm_pool_get_data_block_size() 2015-02-09 13:06:49 -05:00
dm-thin-metadata.h dm thin metadata: remove unused dm_pool_get_data_block_size() 2015-02-09 13:06:49 -05:00
dm-thin.c dm thin: fix to consistently zero-fill reads to unprovisioned blocks 2015-02-27 09:59:12 -05:00
dm-uevent.c md: Add in export.h for files using EXPORT_SYMBOL 2011-10-31 19:31:19 -04:00
dm-uevent.h
dm-verity.c dm verity: fix biovecs hash calculation regression 2014-04-15 12:19:24 -04:00
dm-zero.c dm crypt, dm zero: update author name following legal name change 2014-07-10 16:44:14 -04:00
dm.c dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
dm.h dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
faulty.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
Kconfig dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr 2015-04-15 12:10:17 -04:00
linear.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
linear.h md/linear: typedef removal: linear_conf_t -> struct linear_conf 2011-10-11 16:48:54 +11:00
Makefile dm: add era target 2014-03-27 16:56:23 -04:00
md.c md: fix problems with freeing private data after ->run failure. 2015-03-21 09:40:36 +11:00
md.h md: wakeup thread upon rdev_dec_pending() 2015-02-06 09:32:57 +11:00
multipath.c md: rename ->stop to ->free 2015-02-04 08:35:52 +11:00
multipath.h md/multipath: typedef removal: multipath_conf_t -> struct mpconf 2011-10-11 16:48:57 +11:00
raid0.c md: fix problems with freeing private data after ->run failure. 2015-03-21 09:40:36 +11:00
raid0.h md: add proper merge_bvec handling to RAID0 and Linear. 2012-03-19 12:46:39 +11:00
raid1.c md/raid1: fix read balance when a drive is write-mostly. 2015-02-25 11:37:02 +11:00
raid1.h md: make ->congested robust against personality changes. 2015-02-04 08:35:52 +11:00
raid5.c raid5: check faulty flag for array status during recovery. 2015-02-25 11:38:26 +11:00
raid5.h md: make ->congested robust against personality changes. 2015-02-04 08:35:52 +11:00
raid10.c md/raid10: round up to bdev_logical_block_size in narrow_write_error. 2015-02-16 14:51:54 +11:00
raid10.h md: make ->congested robust against personality changes. 2015-02-04 08:35:52 +11:00