linux-toradex.git/block/ioctl.c, branch v4.9.16

block: invalidate the page cache when issuing BLKZEROOUT

2016-10-11T22:06:30+00:00

Patch series "fallocate for block devices", v11.

This is a patchset to fix page cache coherency with BLKZEROOUT and
implement fallocate for block devices.

The first patch is a fix to the existing BLKZEROOUT ioctl to invalidate
the page cache if the zeroing command to the underlying device succeeds.
Without this patch we still have the pagecache coherence bug that's been
in the kernel forever.

The second patch changes the internal block device functions to reject
attempts to discard or zeroout that are not aligned to the logical block
size.  Previously, we only checked that the start/len parameters were
512-byte aligned, which caused kernel BUG_ONs for unaligned IOs to 4k-LBA
devices.

The third patch creates an fallocate handler for block devices, wires up
the FALLOC_FL_PUNCH_HOLE flag to zeroing-discard, and connects
FALLOC_FL_ZERO_RANGE to write-same so that we can have a consistent
fallocate interface between files and block devices.  It also allows the
combination of PUNCH_HOLE and NO_HIDE_STALE to invoke non-zeroing discard.

Test cases for the new block device fallocate are now in xfstests as
generic/349-351.

This patch (of 3):

Invalidate the page cache (as a regular O_DIRECT write would do) to avoid
returning stale cache contents at a later time.

Link: http://lkml.kernel.org/r/147518378313.22791.16649519283678515021.stgit@birch.djwong.org
Signed-off-by: Darrick J. Wong 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Martin K. Petersen 
Reviewed-by: Bart Van Assche 
Reviewed-by: Hannes Reinecke 
Cc: Theodore Ts'o 
Cc: Mike Snitzer 
Cc: Brian Foster 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'dax-misc-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2016-05-27T02:34:26+00:00

Pull misc DAX updates from Vishal Verma:
 "DAX error handling for 4.7

   - Until now, dax has been disabled if media errors were found on any
     device.  This enables the use of DAX in the presence of these
     errors by making all sector-aligned zeroing go through the driver.

   - The driver (already) has the ability to clear errors on writes that
     are sent through the block layer using 'DSMs' defined in ACPI 6.1.

  Other misc changes:

   - When mounting DAX filesystems, check to make sure the partition is
     page aligned.  This is a requirement for DAX, and previously, we
     allowed such unaligned mounts to succeed, but subsequent
     reads/writes would fail.

   - Misc/cleanup fixes from Jan that remove unused code from DAX
     related to zeroing, writeback, and some size checks"

* tag 'dax-misc-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: fix a comment in dax_zero_page_range and dax_truncate_page
  dax: for truncate/hole-punch, do zeroing through the driver if possible
  dax: export a low-level __dax_zero_page_range helper
  dax: use sb_issue_zerout instead of calling dax_clear_sectors
  dax: enable dax in the presence of known media errors (badblocks)
  dax: fallback from pmd to pte on error
  block: Update blkdev_dax_capable() for consistency
  xfs: Add alignment check for DAX mount
  ext2: Add alignment check for DAX mount
  ext4: Add alignment check for DAX mount
  block: Add bdev_dax_supported() for dax mount checks
  block: Add vfs_msg() interface
  dax: Remove redundant inode size checks
  dax: Remove pointless writeback from dax_do_io()
  dax: Remove zeroing from dax_io()
  dax: Remove dead zeroing code from fault handlers
  ext2: Avoid DAX zeroing to corrupt data
  ext2: Fix block zeroing in ext2_get_blocks() for DAX
  dax: Remove complete_unwritten argument
  DAX: move RADIX_DAX_ definitions to dax.c

Revert "block: enable dax for raw block devices"

2016-05-21T05:02:56+00:00

This reverts commit 5a023cdba50c5f5f2bc351783b3131699deb3937.

The functionality is superseded by the new "Device DAX" facility.

Cc: Jeff Moyer 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Andrew Morton 
Cc: Ross Zwisler 
Cc: Jan Kara 
Signed-off-by: Dan Williams

block: Update blkdev_dax_capable() for consistency

2016-05-17T06:44:13+00:00

blkdev_dax_capable() is similar to bdev_dax_supported(), but needs
to remain as a separate interface for checking dax capability of
a raw block device.

Rename and relocate blkdev_dax_capable() to keep them maintained
consistently, and call bdev_direct_access() for the dax capability
check.

There is no change in the behavior.

Link: https://lkml.org/lkml/2016/5/9/950
Signed-off-by: Toshi Kani 
Reviewed-by: Jan Kara 
Cc: Alexander Viro 
Cc: Jens Axboe 
Cc: Andreas Dilger 
Cc: Jan Kara 
Cc: Dave Chinner 
Cc: Dan Williams 
Cc: Ross Zwisler 
Cc: Christoph Hellwig 
Cc: Boaz Harrosh 
Signed-off-by: Vishal Verma

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

2016-04-04T17:41:08+00:00

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 -  << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 -  >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> ;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov 
Acked-by: Michal Hocko 
Signed-off-by: Linus Torvalds

block: revert runtime dax control of the raw block device

2016-01-30T21:35:31+00:00

Dynamically enabling DAX requires that the page cache first be flushed
and invalidated.  This must occur atomically with the change of DAX mode
otherwise we confuse the fsync/msync tracking and violate data
durability guarantees.  Eliminate the possibilty of DAX-disabled to
DAX-enabled transitions for now and revisit this for the next cycle.

Cc: Jan Kara 
Cc: Jeff Moyer 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Matthew Wilcox 
Cc: Andrew Morton 
Cc: Ross Zwisler 
Signed-off-by: Dan Williams

wrappers for ->i_mutex access

2016-01-22T23:04:28+00:00

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro

pmem, dax: disable dax in the presence of bad blocks

2016-01-10T06:42:31+00:00

Longer term teach dax to punch "error" holes in mapping requests and
deliver SIGBUS to applications that consume a bad pmem page.  For now,
simply disable the dax performance optimization in the presence of known
errors.

Signed-off-by: Dan Williams

block: enable dax for raw block devices

2016-01-09T14:30:49+00:00

If an application wants exclusive access to all of the persistent memory
provided by an NVDIMM namespace it can use this raw-block-dax facility
to forgo establishing a filesystem.  This capability is targeted
primarily to hypervisors wanting to provision persistent memory for
guests.  It can be disabled / enabled dynamically via the new BLKDAXSET
ioctl.

Cc: Jeff Moyer 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Andrew Morton 
Cc: Ross Zwisler 
Reported-by: kbuild test robot 
Reviewed-by: Jan Kara 
Signed-off-by: Dan Williams

block: add an API for Persistent Reservations

2015-10-21T20:46:56+00:00

This commits adds a driver API and ioctls for controlling Persistent
Reservations s/genericly/generically/ at the block layer.  Persistent
Reservations are supported by SCSI and NVMe and allow controlling who gets
access to a device in a shared storage setup.

Note that we add a pr_ops structure to struct block_device_operations
instead of adding the members directly to avoid bloating all instances
of devices that will never support Persistent Reservations.

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