linux.git/drivers/md/dm-table.c, branch v4.9

dm table: fix missing dm_put_target_type() in dm_table_add_target()

2016-10-24T15:17:46+00:00

dm_get_target_type() was previously called so any error returned from
dm_table_add_target() must first call dm_put_target_type().  Otherwise
the DM target module's reference count will leak and the associated
kernel module will be unable to be removed.

Also, leverage the fact that r is already -EINVAL and remove an extra
newline.

Fixes: 36a0456 ("dm table: add immutable feature")
Fixes: cc6cbe1 ("dm table: add always writeable feature")
Fixes: 3791e2f ("dm table: add singleton feature")
Cc: stable@vger.kernel.org # 3.2+
Signed-off-by: tang.junhui 
Signed-off-by: Mike Snitzer

dm error: add DAX support

2016-07-21T03:49:50+00:00

Allow the error target to replace an existing DAX-enabled target.

Signed-off-by: Mike Snitzer

dm: add infrastructure for DAX support

2016-07-21T03:49:49+00:00

Change mapped device to implement direct_access function,
dm_blk_direct_access(), which calls a target direct_access function.
'struct target_type' is extended to have target direct_access interface.
This function limits direct accessible size to the dm_target's limit
with max_io_len().

Add dm_table_supports_dax() to iterate all targets and associated block
devices to check for DAX support.  To add DAX support to a DM target the
target must only implement the direct_access function.

Add a new dm type, DM_TYPE_DAX_BIO_BASED, which indicates that mapped
device supports DAX and is bio based.  This new type is used to assure
that all target devices have DAX support and remain that way after
QUEUE_FLAG_DAX is set in mapped device.

At initial table load, QUEUE_FLAG_DAX is set to mapped device when setting
DM_TYPE_DAX_BIO_BASED to the type.  Any subsequent table load to the
mapped device must have the same type, or else it fails per the check in
table_load().

Signed-off-by: Toshi Kani 
Signed-off-by: Mike Snitzer

dm mpath: add optional "queue_mode" feature

2016-06-10T19:16:02+00:00

Allow a user to specify an optional feature 'queue_mode ' where
 may be "bio", "rq" or "mq" -- which corresponds to bio-based,
request_fn rq-based, and blk-mq rq-based respectively.

If the queue_mode feature isn't specified the default for the
"multipath" target is still "rq" but if dm_mod.use_blk_mq is set to Y
it'll default to mode "mq".

This new queue_mode feature introduces the ability for each multipath
device to have its own queue_mode (whereas before this feature all
multipath devices effectively had to have the same queue_mode).

This commit also goes a long way to eliminate the awkward (ab)use of
DM_TYPE_*, the associated filter_md_type() and other relatively fragile
and difficult to maintain code.

Signed-off-by: Mike Snitzer

dm: move request-based code out to dm-rq.[hc]

2016-06-10T19:15:44+00:00

Add some seperation between bio-based and request-based DM core code.

'struct mapped_device' and other DM core only structures and functions
have been moved to dm-core.h and all relevant DM core .c files have been
updated to include dm-core.h rather than dm.h

DM targets should _never_ include dm-core.h!

[block core merge conflict resolution from Stephen Rothwell]
Signed-off-by: Mike Snitzer 
Signed-off-by: Stephen Rothwell

block: kill off q->flush_flags

2016-04-13T19:33:19+00:00

Now that we converted everything to the newer block write cache
interface, kill off the queue flush_flags and queueable flush
entries.

Signed-off-by: Jens Axboe

dm: switch to using blk_queue_write_cache()

2016-04-12T22:00:39+00:00

Signed-off-by: Jens Axboe 
Reviewed-by: Christoph Hellwig

dm snapshot: disallow the COW and origin devices from being identical

2016-03-10T22:12:09+00:00

Otherwise loading a "snapshot" table using the same device for the
origin and COW devices, e.g.:

echo "0 20971520 snapshot 253:3 253:3 P 8" | dmsetup create snap

will trigger:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000098
[ 1958.979934] IP: [] dm_exception_store_set_chunk_size+0x7a/0x110 [dm_snapshot]
[ 1958.989655] PGD 0
[ 1958.991903] Oops: 0000 [#1] SMP
...
[ 1959.059647] CPU: 9 PID: 3556 Comm: dmsetup Tainted: G          IO    4.5.0-rc5.snitm+ #150
...
[ 1959.083517] task: ffff8800b9660c80 ti: ffff88032a954000 task.ti: ffff88032a954000
[ 1959.091865] RIP: 0010:[]  [] dm_exception_store_set_chunk_size+0x7a/0x110 [dm_snapshot]
[ 1959.104295] RSP: 0018:ffff88032a957b30  EFLAGS: 00010246
[ 1959.110219] RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000000001
[ 1959.118180] RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff880329334a00
[ 1959.126141] RBP: ffff88032a957b50 R08: 0000000000000000 R09: 0000000000000001
[ 1959.134102] R10: 000000000000000a R11: f000000000000000 R12: ffff880330884d80
[ 1959.142061] R13: 0000000000000008 R14: ffffc90001c13088 R15: ffff880330884d80
[ 1959.150021] FS:  00007f8926ba3840(0000) GS:ffff880333440000(0000) knlGS:0000000000000000
[ 1959.159047] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1959.165456] CR2: 0000000000000098 CR3: 000000032f48b000 CR4: 00000000000006e0
[ 1959.173415] Stack:
[ 1959.175656]  ffffc90001c13040 ffff880329334a00 ffff880330884ed0 ffff88032a957bdc
[ 1959.183946]  ffff88032a957bb8 ffffffffa040f225 ffff880329334a30 ffff880300000000
[ 1959.192233]  ffffffffa04133e0 ffff880329334b30 0000000830884d58 00000000569c58cf
[ 1959.200521] Call Trace:
[ 1959.203248]  [] dm_exception_store_create+0x1d5/0x240 [dm_snapshot]
[ 1959.211986]  [] snapshot_ctr+0x140/0x630 [dm_snapshot]
[ 1959.219469]  [] ? dm_split_args+0x64/0x150 [dm_mod]
[ 1959.226656]  [] dm_table_add_target+0x177/0x440 [dm_mod]
[ 1959.234328]  [] table_load+0x143/0x370 [dm_mod]
[ 1959.241129]  [] ? retrieve_status+0x1b0/0x1b0 [dm_mod]
[ 1959.248607]  [] ctl_ioctl+0x255/0x4d0 [dm_mod]
[ 1959.255307]  [] ? memzero_explicit+0x12/0x20
[ 1959.261816]  [] dm_ctl_ioctl+0x13/0x20 [dm_mod]
[ 1959.268615]  [] do_vfs_ioctl+0xa6/0x5c0
[ 1959.274637]  [] ? __audit_syscall_entry+0xaf/0x100
[ 1959.281726]  [] ? do_audit_syscall_entry+0x66/0x70
[ 1959.288814]  [] SyS_ioctl+0x79/0x90
[ 1959.294450]  [] entry_SYSCALL_64_fastpath+0x12/0x71
...
[ 1959.323277] RIP  [] dm_exception_store_set_chunk_size+0x7a/0x110 [dm_snapshot]
[ 1959.333090]  RSP 
[ 1959.336978] CR2: 0000000000000098
[ 1959.344121] ---[ end trace b049991ccad1169e ]---

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1195899
Cc: stable@vger.kernel.org
Signed-off-by: Ding Xiang 
Signed-off-by: Mike Snitzer

dm: rename target's per_bio_data_size to per_io_data_size

2016-02-23T03:34:37+00:00

Request-based DM will also make use of per_bio_data_size.

Signed-off-by: Mike Snitzer

dm: optimize dm_mq_queue_rq()

2016-02-22T16:06:22+00:00

DM multipath is the only dm-mq target.  But that aside, request-based DM
only supports tables with a single target that is immutable.  Leverage
this fact in dm_mq_queue_rq() by using the 'immutable_target' stored in
the mapped_device when the table was made active.  This saves the need
to even take the read-side of the SRCU via dm_{get,put}_live_table.

If the active DM table does not have an immutable target (e.g. "error"
target was swapped in) then fallback to the slow-path where the target
is looked up from the live table.

Signed-off-by: Mike Snitzer