linux.git/drivers/dax/super.c, branch v5.19

dax: add .recovery_write dax_operation

2022-05-16T20:37:59+00:00

Introduce dax_recovery_write() operation. The function is used to
recover a dax range that contains poison. Typical use case is when
a user process receives a SIGBUS with si_code BUS_MCEERR_AR
indicating poison(s) in a dax range, in response, the user process
issues a pwrite() to the page-aligned dax range, thus clears the
poison and puts valid data in the range.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Jane Chu 
Link: https://lore.kernel.org/r/20220422224508.440670-6-jane.chu@oracle.com
Signed-off-by: Dan Williams

dax: introduce DAX_RECOVERY_WRITE dax access mode

2022-05-16T20:35:56+00:00

Up till now, dax_direct_access() is used implicitly for normal
access, but for the purpose of recovery write, dax range with
poison is requested.  To make the interface clear, introduce
	enum dax_access_mode {
		DAX_ACCESS,
		DAX_RECOVERY_WRITE,
	}
where DAX_ACCESS is used for normal dax access, and
DAX_RECOVERY_WRITE is used for dax recovery write.

Suggested-by: Dan Williams 
Signed-off-by: Jane Chu 
Reviewed-by: Christoph Hellwig 
Cc: Mike Snitzer 
Reviewed-by: Vivek Goyal 
Link: https://lore.kernel.org/r/165247982851.52965.11024212198889762949.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams

Merge tag 'dax-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2022-03-25T01:12:09+00:00

Pull DAX updates from Dan Williams:
 "Andrew has been shepherding major dax features that touch the core -mm
  through his tree, but I still collect the dax updates that are core-mm
  independent.

   - Fix a crash due to a missing rcu_barrier() in dax_fs_exit()

   - Fix two miscellaneous doc issues"

* tag 'dax-for-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix missing kdoc for dax_device
  dax: make sure inodes are flushed before destroy cache
  fsdax: fix function description

fs: allocate inode by using alloc_inode_sb()

2022-03-22T22:57:03+00:00

The inode allocation is supposed to use alloc_inode_sb(), so convert
kmem_cache_alloc() of all filesystems to alloc_inode_sb().

Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com
Signed-off-by: Muchun Song 
Acked-by: Theodore Ts'o 		[ext4]
Acked-by: Roman Gushchin 
Cc: Alex Shi 
Cc: Anna Schumaker 
Cc: Chao Yu 
Cc: Dave Chinner 
Cc: Fam Zheng 
Cc: Jaegeuk Kim 
Cc: Johannes Weiner 
Cc: Kari Argillander 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Qi Zheng 
Cc: Shakeel Butt 
Cc: Trond Myklebust 
Cc: Vladimir Davydov 
Cc: Vlastimil Babka 
Cc: Wei Yang 
Cc: Xiongchun Duan 
Cc: Yang Shi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

dax: Fix missing kdoc for dax_device

2022-03-12T21:46:25+00:00

struct dax_device has a member named ops which was undocumented.

Add the kdoc.

Signed-off-by: Ira Weiny 
Link: https://lore.kernel.org/r/20220304204655.3489216-1-ira.weiny@intel.com
Signed-off-by: Dan Williams

dax: make sure inodes are flushed before destroy cache

2022-02-18T00:57:27+00:00

A bug can be triggered by following command

$ modprobe nd_pmem && modprobe -r nd_pmem

[   10.060014] BUG dax_cache (Not tainted): Objects remaining in dax_cache on __kmem_cache_shutdown()
[   10.060938] Slab 0x0000000085b729ac objects=9 used=1 fp=0x000000004f5ae469 flags=0x200000000010200(slab|head|node)
[   10.062433] Call Trace:
[   10.062673]  dump_stack_lvl+0x34/0x44
[   10.062865]  slab_err+0x90/0xd0
[   10.063619]  __kmem_cache_shutdown+0x13b/0x2f0
[   10.063848]  kmem_cache_destroy+0x4a/0x110
[   10.064058]  __x64_sys_delete_module+0x265/0x300

This is caused by dax_fs_exit() not flushing inodes before destroy cache.
To fix this issue, call rcu_barrier() before destroy cache.

Signed-off-by: Tong Zhang 
Reviewed-by: Ira Weiny 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20220212071111.148575-1-ztong0001@gmail.com
Fixes: 7b6be8444e0f ("dax: refactor dax-fs into a generic provider of 'struct dax_device' instances")
Signed-off-by: Dan Williams

dax: remove the copy_from_iter and copy_to_iter methods

2021-12-18T16:04:53+00:00

These methods indirect the actual DAX read/write path.  In the end pmem
uses magic flush and mc safe variants and fuse and dcssblk use plain ones
while device mapper picks redirects to the underlying device.

Add set_dax_nocache() and set_dax_nomc() APIs to control which copy
routines are used to remove indirect call from the read/write fast path
as well as a lot of boilerplate code.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Vivek Goyal  [virtiofs]
Link: https://lore.kernel.org/r/20211215084508.435401-5-hch@lst.de
Signed-off-by: Dan Williams

dax: remove the DAXDEV_F_SYNC flag

2021-12-18T16:04:52+00:00

Remove the DAXDEV_F_SYNC flag and thus the flags argument to alloc_dax and
just let the drivers call set_dax_synchronous directly.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Pankaj Gupta 
Reviewed-by: Dan Williams 
Link: https://lore.kernel.org/r/20211215084508.435401-4-hch@lst.de
Signed-off-by: Dan Williams

dax: simplify dax_synchronous and set_dax_synchronous

2021-12-18T16:04:52+00:00

Remove the pointless wrappers.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Pankaj Gupta 
Reviewed-by: Dan Williams 
Link: https://lore.kernel.org/r/20211215084508.435401-3-hch@lst.de
Signed-off-by: Dan Williams

dax: return the partition offset from fs_dax_get_by_bdev

2021-12-04T16:58:54+00:00

Prepare for the removal of the block_device from the DAX I/O path by
returning the partition offset from fs_dax_get_by_bdev so that the file
systems have it at hand for use during I/O.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dan Williams 
Reviewed-by: Darrick J. Wong 
Link: https://lore.kernel.org/r/20211129102203.2243509-26-hch@lst.de
Signed-off-by: Dan Williams