linux-stable.git/drivers/md/dm-table.c, branch linux-5.8.y

dm: Call proper helper to determine dax support

2020-09-23T11:00:03+00:00

commit e2ec5128254518cae320d5dc631b71b94160f663 upstream.

DM was calling generic_fsdax_supported() to determine whether a device
referenced in the DM table supports DAX. However this is a helper for "leaf" device drivers so that
they don't have to duplicate common generic checks. High level code
should call dax_supported() helper which that calls into appropriate
helper for the particular device. This problem manifested itself as
kernel messages:

dm-3: error: dax access failed (-95)

when lvm2-testsuite run in cases where a DM device was stacked on top of
another DM device.

Fixes: 7bf7eac8d648 ("dax: Arrange for dax_supported check to span multiple devices")
Cc: 
Tested-by: Adrian Huang 
Signed-off-by: Jan Kara 
Acked-by: Mike Snitzer 
Reported-by: kernel test robot 
Link: https://lore.kernel.org/r/160061715195.13131.5503173247632041975.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman

dm: remove the make_request_fn check in device_area_is_invalid

2020-04-25T15:45:43+00:00

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

block: don't handle bio based drivers in blk_revalidate_disk_zones

2019-12-03T15:51:25+00:00

bio based drivers only need to update q->nr_zones.  Do that manually
instead of overloading blk_revalidate_disk_zones to keep that function
simpler for the next round of changes that will rely even more on the
request based functionality.

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

dm table: do not allow request-based DM to stack on partitions

2019-11-05T16:22:52+00:00

Partitioned request-based devices cannot be used as underlying devices
for request-based DM because no partition offsets are added to each
incoming request.  As such, until now, stacking on partitioned devices
would _always_ result in data corruption (e.g. wiping the partition
table, writing to other partitions, etc).  Fix this by disallowing
request-based stacking on partitions.

While at it, since all .request_fn support has been removed from block
core, remove legacy dm-table code that differentiated between blk-mq and
.request_fn request-based.

Signed-off-by: Mike Snitzer

dm: make dm_table_find_target return NULL

2019-08-23T14:13:12+00:00

Currently, if we pass too high sector number to dm_table_find_target, it
returns zeroed dm_target structure and callers test if the structure is
zeroed with the macro dm_target_is_valid.

However, returning NULL is common practice to indicate errors.

This patch refactors the dm code, so that dm_table_find_target returns
NULL and its callers test the returned value for NULL. The macro
dm_target_is_valid is deleted. In alloc_targets, we no longer allocate an
extra zeroed target.

Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm table: fix invalid memory accesses with too high sector number

2019-08-23T14:11:42+00:00

If the sector number is too high, dm_table_find_target() should return a
pointer to a zeroed dm_target structure (the caller should test it with
dm_target_is_valid).

However, for some table sizes, the code in dm_table_find_target() that
performs btree lookup will access out of bound memory structures.

Fix this bug by testing the sector number at the beginning of
dm_table_find_target(). Also, add an "inline" keyword to the function
dm_table_get_size() because this is a hot path.

Fixes: 512875bd9661 ("dm: table detect io beyond device")
Cc: stable@vger.kernel.org
Reported-by: Zhang Tao 
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm table: fix various whitespace issues with recent DAX code

2019-07-30T22:59:24+00:00

Also, rename device_synchronous to device_dax_synchronous.

Signed-off-by: Mike Snitzer

dm table: fix dax_dev NULL dereference in device_synchronous()

2019-07-30T22:58:54+00:00

If a device doesn't support DAX its 'dax_dev' is NULL.  Fix
device_synchronous() to first check if dax_dev is NULL before
dereferencing it.

Fixes: 2e9ee0955d3c ("dm: enable synchronous dax")
Reported-by: jencce.kernel@gmail.com
Signed-off-by: Pankaj Gupta 
Acked-by: Dan Williams 
Signed-off-by: Mike Snitzer

Merge tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2019-07-18T17:52:08+00:00

Pull libnvdimm updates from Dan Williams:
 "Primarily just the virtio_pmem driver:

   - virtio_pmem

     The new virtio_pmem facility introduces a paravirtualized
     persistent memory device that allows a guest VM to use DAX
     mechanisms to access a host-file with host-page-cache. It arranges
     for MAP_SYNC to be disabled and instead triggers a host fsync()
     when a 'write-cache flush' command is sent to the virtual disk
     device.

   - Miscellaneous small fixups"

* tag 'libnvdimm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  virtio_pmem: fix sparse warning
  xfs: disable map_sync for async flush
  ext4: disable map_sync for async flush
  dax: check synchronous mapping is supported
  dm: enable synchronous dax
  libnvdimm: add dax_dev sync flag
  virtio-pmem: Add virtio pmem driver
  libnvdimm: nd_region flush callback support
  libnvdimm, namespace: Drop uuid_t implementation detail

dm: enable synchronous dax

2019-07-05T22:19:10+00:00

This patch sets dax device 'DAXDEV_SYNC' flag if all the target
devices of device mapper support synchrononous DAX. If device
mapper consists of both synchronous and asynchronous dax devices,
we don't set 'DAXDEV_SYNC' flag.

'dm_table_supports_dax' is refactored to pass 'iterate_devices_fn'
as argument so that the callers can pass the appropriate functions.

Suggested-by: Mike Snitzer 
Signed-off-by: Pankaj Gupta 
Reviewed-by: Mike Snitzer 
Signed-off-by: Dan Williams