linux/drivers/md
Shiyang Ruan 8012b86608 dax: introduce holder for dax_device
Patch series "v14 fsdax-rmap + v11 fsdax-reflink", v2.

The patchset fsdax-rmap is aimed to support shared pages tracking for
fsdax.

It moves owner tracking from dax_assocaite_entry() to pmem device driver,
by introducing an interface ->memory_failure() for struct pagemap.  This
interface is called by memory_failure() in mm, and implemented by pmem
device.

Then call holder operations to find the filesystem which the corrupted
data located in, and call filesystem handler to track files or metadata
associated with this page.

Finally we are able to try to fix the corrupted data in filesystem and do
other necessary processing, such as killing processes who are using the
files affected.

The call trace is like this:
memory_failure()
|* fsdax case
|------------
|pgmap->ops->memory_failure()      => pmem_pgmap_memory_failure()
| dax_holder_notify_failure()      =>
|  dax_device->holder_ops->notify_failure() =>
|                                     - xfs_dax_notify_failure()
|  |* xfs_dax_notify_failure()
|  |--------------------------
|  |   xfs_rmap_query_range()
|  |    xfs_dax_failure_fn()
|  |    * corrupted on metadata
|  |       try to recover data, call xfs_force_shutdown()
|  |    * corrupted on file data
|  |       try to recover data, call mf_dax_kill_procs()
|* normal case
|-------------
|mf_generic_kill_procs()


The patchset fsdax-reflink attempts to add CoW support for fsdax, and
takes XFS, which has both reflink and fsdax features, as an example.

One of the key mechanisms needed to be implemented in fsdax is CoW.  Copy
the data from srcmap before we actually write data to the destination
iomap.  And we just copy range in which data won't be changed.

Another mechanism is range comparison.  In page cache case, readpage() is
used to load data on disk to page cache in order to be able to compare
data.  In fsdax case, readpage() does not work.  So, we need another
compare data with direct access support.

With the two mechanisms implemented in fsdax, we are able to make reflink
and fsdax work together in XFS.


This patch (of 14):

To easily track filesystem from a pmem device, we introduce a holder for
dax_device structure, and also its operation.  This holder is used to
remember who is using this dax_device:

 - When it is the backend of a filesystem, the holder will be the
   instance of this filesystem.
 - When this pmem device is one of the targets in a mapped device, the
   holder will be this mapped device.  In this case, the mapped device
   has its own dax_device and it will follow the first rule.  So that we
   can finally track to the filesystem we needed.

The holder and holder_ops will be set when filesystem is being mounted,
or an target device is being activated.

Link: https://lkml.kernel.org/r/20220603053738.1218681-1-ruansy.fnst@fujitsu.com
Link: https://lkml.kernel.org/r/20220603053738.1218681-2-ruansy.fnst@fujitsu.com
Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.wiliams@intel.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Goldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:30 -07:00
..
bcache mm: shrinkers: provide shrinkers with names 2022-07-03 18:08:40 -07:00
persistent-data dm space map common: add bounds check to sm_ll_lookup_bitmap() 2022-01-04 13:58:19 -05:00
dm-audit.c dm: introduce audit event module for device mapper 2021-10-27 16:53:47 -04:00
dm-audit.h dm: introduce audit event module for device mapper 2021-10-27 16:53:47 -04:00
dm-bio-prison-v1.c
dm-bio-prison-v1.h
dm-bio-prison-v2.c
dm-bio-prison-v2.h
dm-bio-record.h block: move integrity handling out of <linux/blkdev.h> 2021-10-18 06:17:02 -06:00
dm-bufio.c mm: shrinkers: provide shrinkers with names 2022-07-03 18:08:40 -07:00
dm-builtin.c
dm-cache-background-tracker.c
dm-cache-background-tracker.h
dm-cache-block-types.h
dm-cache-metadata.c dm cache metadata: remove unnecessary variable in __dump_mapping 2022-05-09 15:40:10 -04:00
dm-cache-metadata.h
dm-cache-policy-internal.h
dm-cache-policy-smq.c dm cache policy smq: make static read-only array table const 2022-02-22 10:35:53 -05:00
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c block: remove QUEUE_FLAG_DISCARD 2022-04-17 19:49:59 -06:00
dm-clone-metadata.c dm clone metadata: remove unused function 2021-04-19 13:20:31 -04:00
dm-clone-metadata.h
dm-clone-target.c block: remove QUEUE_FLAG_DISCARD 2022-04-17 19:49:59 -06:00
dm-core.h dm: fix BLK_STS_DM_REQUEUE handling when dm_io represents split bio 2022-06-23 14:33:13 -04:00
dm-crypt.c dm crypt: make printing of the key constant-time 2022-05-09 12:34:03 -04:00
dm-delay.c dm: simplify basic targets 2022-05-05 17:31:35 -04:00
dm-dust.c dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them 2021-10-18 14:43:22 -06:00
dm-ebs-target.c scsi: dm: Remove WRITE_SAME support 2022-02-22 21:11:08 -05:00
dm-era-target.c dm era: commit metadata in postsuspend after worker stops 2022-06-21 13:35:01 -04:00
dm-exception-store.c
dm-exception-store.h dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them 2021-10-18 14:43:22 -06:00
dm-flakey.c dm: simplify basic targets 2022-05-05 17:31:35 -04:00
dm-ima.c dm ima: fix wrong length calculation for no_data string 2022-02-22 10:42:41 -05:00
dm-ima.h dm ima: add version info to dm related events in ima log 2021-08-20 15:59:47 -04:00
dm-init.c
dm-integrity.c dm integrity: fix error code in dm_integrity_ctr() 2022-05-09 12:14:00 -04:00
dm-io-tracker.h dm writecache: make writeback pause configurable 2021-06-28 16:30:13 -04:00
dm-io.c block: add a bdev_max_discard_sectors helper 2022-04-17 19:49:59 -06:00
dm-ioctl.c dm ioctl: log an error if the ioctl structure is corrupted 2022-04-01 10:29:43 -04:00
dm-kcopyd.c dm writecache: have ssd writeback wait if the kcopyd workqueue is busy 2021-06-15 15:42:03 -04:00
dm-linear.c libnvdimm for 5.19 2022-05-27 15:49:30 -07:00
dm-log-userspace-base.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c libnvdimm for 5.19 2022-05-27 15:49:30 -07:00
dm-log.c dm mirror log: clear log bits up to BITS_PER_LONG boundary 2022-06-23 14:55:43 -04:00
dm-mpath.c dm mpath: provide high-resolution timer to HST for bio-based 2022-05-09 15:39:23 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h dm mpath: provide high-resolution timer to HST for bio-based 2022-05-09 15:39:23 -04:00
dm-ps-historical-service-time.c dm mpath: provide high-resolution timer to HST for bio-based 2022-05-09 15:39:23 -04:00
dm-ps-io-affinity.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-ps-queue-length.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-ps-round-robin.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-ps-service-time.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-raid1.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-raid.c Revert "md: don't unregister sync_thread with reconfig_mutex held" 2022-06-15 10:30:14 -07:00
dm-region-hash.c
dm-rq.c dm: fix bio_set allocation 2022-06-08 14:04:14 -04:00
dm-rq.h
dm-snap-persistent.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-snap-transient.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-snap.c dm-snap: use blkdev_issue_flush instead of open coding it 2022-02-02 07:49:59 -07:00
dm-stats.c dm stats: add cond_resched when looping over entries 2022-05-09 12:11:07 -04:00
dm-stats.h dm stats: fix too short end duration_ns when using precise_timestamps 2022-02-21 15:35:39 -05:00
dm-stripe.c dax: add .recovery_write dax_operation 2022-05-16 13:37:59 -07:00
dm-switch.c dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them 2021-10-18 14:43:22 -06:00
dm-sysfs.c dm sysfs: use default_groups in kobj_type 2022-01-06 09:48:55 -05:00
dm-table.c dm: fix bio_set allocation 2022-06-08 14:04:14 -04:00
dm-target.c dax: introduce DAX_RECOVERY_WRITE dax access mode 2022-05-16 13:35:56 -07:00
dm-thin-metadata.c dm thin metadata: remove unused dm_thin_remove_block and __remove 2022-02-22 13:55:50 -05:00
dm-thin-metadata.h dm thin metadata: remove unused dm_thin_remove_block and __remove 2022-02-22 13:55:50 -05:00
dm-thin.c block: decouple REQ_OP_SECURE_ERASE from REQ_OP_DISCARD 2022-04-17 19:49:59 -06:00
dm-uevent.c
dm-uevent.h
dm-unstripe.c dm: update target status functions to support IMA measurement 2021-08-10 13:34:23 -04:00
dm-verity-fec.c dm verity fec: fix misaligned RS roots IO 2021-04-14 14:28:29 -04:00
dm-verity-fec.h dm verity fec: fix misaligned RS roots IO 2021-04-14 14:28:29 -04:00
dm-verity-target.c dm verity: set DM_TARGET_IMMUTABLE feature flag 2022-05-31 16:22:30 -04:00
dm-verity-verify-sig.c dm verity: fix require_signatures module_param permissions 2021-05-25 16:14:05 -04:00
dm-verity-verify-sig.h
dm-verity.h
dm-writecache.c dax: introduce DAX_RECOVERY_WRITE dax access mode 2022-05-16 13:35:56 -07:00
dm-zero.c dm: add support for REQ_NOWAIT to various targets 2020-12-04 18:04:35 -05:00
dm-zone.c dm: don't grab target io reference in dm_zone_map_bio 2022-05-05 17:31:36 -04:00
dm-zoned-metadata.c mm: shrinkers: provide shrinkers with names 2022-07-03 18:08:40 -07:00
dm-zoned-reclaim.c dm kcopyd: avoid useless atomic operations 2021-06-04 12:07:24 -04:00
dm-zoned-target.c dm-zoned: don't set the discard_alignment queue limit 2022-05-03 10:38:50 -06:00
dm-zoned.h dm-zoned: remove the ->name field in struct dmz_dev 2022-03-02 12:15:35 -05:00
dm.c dax: introduce holder for dax_device 2022-07-17 17:14:30 -07:00
dm.h dm: fix bio_set allocation 2022-06-08 14:04:14 -04:00
Kconfig blk-mq: make the blk-mq stacking code optional 2022-02-16 19:39:09 -07:00
Makefile dm: introduce audit event module for device mapper 2021-10-27 16:53:47 -04:00
md-autodetect.c
md-bitmap.c md: replace deprecated strlcpy & remove duplicated line 2022-04-25 14:00:36 -07:00
md-bitmap.h
md-cluster.c md: replace deprecated strlcpy & remove duplicated line 2022-04-25 14:00:36 -07:00
md-cluster.h
md-faulty.c block: pass a block_device to bio_clone_fast 2022-02-04 07:43:18 -07:00
md-linear.c md: remove most calls to bdevname 2022-05-22 23:07:21 -07:00
md-linear.h
md-multipath.c md: remove most calls to bdevname 2022-05-22 23:07:21 -07:00
md-multipath.h
md.c Revert "md: don't unregister sync_thread with reconfig_mutex held" 2022-06-15 10:30:14 -07:00
md.h Revert "md: don't unregister sync_thread with reconfig_mutex held" 2022-06-15 10:30:14 -07:00
raid0.c md: Don't set mddev private to NULL in raid0 pers->free 2022-05-22 23:07:21 -07:00
raid0.h
raid1-10.c md: raid1/raid10: drop pending_cnt 2022-03-08 15:16:54 -08:00
raid1.c md: remove most calls to bdevname 2022-05-22 23:07:21 -07:00
raid1.h md: raid1/raid10: drop pending_cnt 2022-03-08 15:16:54 -08:00
raid5-cache.c md: remove most calls to bdevname 2022-05-22 23:07:21 -07:00
raid5-log.h
raid5-ppl.c md/raid5-ppl: Fix argument order in bio_alloc_bioset() 2022-06-15 10:32:48 -07:00
raid5.c mm: shrinkers: provide shrinkers with names 2022-07-03 18:08:40 -07:00
raid5.h md/raid5: Add __rcu annotation to struct disk_info 2022-04-25 14:00:36 -07:00
raid10.c md: remove most calls to bdevname 2022-05-22 23:07:21 -07:00
raid10.h md: raid1/raid10: drop pending_cnt 2022-03-08 15:16:54 -08:00