Some drivers often use external bvec table, so introduce
this helper for this case. It is always safe to access the
bio->bi_io_vec in this way for this case.
After converting to this usage, it will becomes a bit easier
to evaluate the remaining direct access to bio->bi_io_vec,
so it can help to prepare for the following multipage bvec
support.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixed up the new O_DIRECT cases.
Signed-off-by: Jens Axboe <axboe@fb.com>
We store the bits in the bdev sector size locally, but we don't use
the calculation anymore. All we do with it is shift it back up to
the bdev sector size. So let's just use that directly and kill the
variable and bits calculation.
Signed-off-by: Jens Axboe <axboe@fb.com>
A direct I/O alignment must be always checked against the device blocks size,
but the I/O offset (bio->bi_iter.bi_sector must always use 512B sector unit, and
not the actual logical block size.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Similar to the simple fast path, but we now need a dio structure to
track multiple-bio completions. It's basically a cut-down version
of the new iomap-based direct I/O code for filesystems, but without
all the logic to call into the filesystem for extent lookup or
allocation, and without the complex I/O completion workqueue handler
for AIO - instead we just use the FUA bit on the bios to ensure
data is flushed to stable storage.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This patch adds a small and simple fast patch for small direct I/O
requests on block devices that don't use AIO. Between the neat
bio_iov_iter_get_pages helper that avoids allocating a page array
for get_user_pages and the on-stack bio and biovec this avoid memory
allocations and atomic operations entirely in the direct I/O code
(lower levels might still do memory allocations and will usually
have at least some atomic operations, though).
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Tested-By: Stephen Bates <sbates@raithlin.com>
Reviewed-By: Stephen Bates <sbates@raithlin.com>
After much discussion, it seems that the fallocate feature flag
FALLOC_FL_ZERO_RANGE maps nicely to SCSI WRITE SAME; and the feature
FALLOC_FL_PUNCH_HOLE maps nicely to the devices that have been whitelisted
for zeroing SCSI UNMAP. Punch still requires that FALLOC_FL_KEEP_SIZE is
set. A length that goes past the end of the device will be clamped to the
device size if KEEP_SIZE is set; or will return -EINVAL if not. Both
start and length must be aligned to the device's logical block size.
Since the semantics of fallocate are fairly well established already, wire
up the two pieces. The other fallocate variants (collapse range, insert
range, and allocate blocks) are not supported.
Link: http://lkml.kernel.org/r/147518379992.22791.8849838163218235007.stgit@birch.djwong.org
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Mike Snitzer <snitzer@redhat.com> # tweaked header
Cc: Brian Foster <bfoster@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When triggering thaw-filesystems via magic sysrq, the system enters a
loop in do_thaw_one(), as thaw_bdev() still returns success if
bd_fsfreeze_count == 0. To fix this, let thaw_bdev() always return
error (and simplify the code a bit at the same time).
Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
DAX support for block devices was removed in commits 03cdad
("block: disable block device DAX by default") and 99a01cd
("block: remove BLK_DEV_DAX config option"), but we still kept a call to
dax_do_io and some uneeded i_flags manipulations introduced in commit
bbab37 ("block: Add support for DAX reads/writes to block devices").
Remove those leftovers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Calling freeze_bdev() twice on the same block device without mounted
filesystem get_super() will return NULL, which will lead to NULL-ptr
dereference later in drop_super().
Check get_super() result to fix that.
Note, that this is a purely theoretical issue. We have only 3
freeze_bdev() callers. 2 of them are in filesystem code and used on a
device with mounted fs. The third one in lock_fs() has protection in
upper-layer code against freezing block device the second time without
thawing it first.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Commit abf545484d changed it from an 'rw' flags type to the
newer ops based interface, but now we're effectively leaking
some bdev internals to the rest of the kernel. Since we only
care about whether it's a read or a write at that level, just
pass in a bool 'is_write' parameter instead.
Then we can also move op_is_write() and friends back under
CONFIG_BLOCK protection.
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The rw_page users were not converted to use bio/req ops. As a result
bdev_write_page is not passing down REQ_OP_WRITE and the IOs will
be sent down as reads.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixes: 4e1b2d52a8 ("block, fs, drivers: remove REQ_OP compat defs and related code")
Modified by me to:
1) Drop op_flags passing into ->rw_page(), as we don't use it.
2) Make op_is_write() and friends safe to use for !CONFIG_BLOCK
Signed-off-by: Jens Axboe <axboe@fb.com>
The functionality for block device DAX was already removed with commit
acc93d30d7 ("Revert "block: enable dax for raw block devices"")
However, we still had a config option hanging around that was always
disabled because it depended on CONFIG_BROKEN. This config option was
introduced in commit 03cdadb040 ("block: disable block device DAX by
default")
This change reverts that commit, removing the dead config option.
Link: http://lkml.kernel.org/r/20160729182314.6368-1-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull userns vfs updates from Eric Biederman:
"This tree contains some very long awaited work on generalizing the
user namespace support for mounting filesystems to include filesystems
with a backing store. The real world target is fuse but the goal is
to update the vfs to allow any filesystem to be supported. This
patchset is based on a lot of code review and testing to approach that
goal.
While looking at what is needed to support the fuse filesystem it
became clear that there were things like xattrs for security modules
that needed special treatment. That the resolution of those concerns
would not be fuse specific. That sorting out these general issues
made most sense at the generic level, where the right people could be
drawn into the conversation, and the issues could be solved for
everyone.
At a high level what this patchset does a couple of simple things:
- Add a user namespace owner (s_user_ns) to struct super_block.
- Teach the vfs to handle filesystem uids and gids not mapping into
to kuids and kgids and being reported as INVALID_UID and
INVALID_GID in vfs data structures.
By assigning a user namespace owner filesystems that are mounted with
only user namespace privilege can be detected. This allows security
modules and the like to know which mounts may not be trusted. This
also allows the set of uids and gids that are communicated to the
filesystem to be capped at the set of kuids and kgids that are in the
owning user namespace of the filesystem.
One of the crazier corner casees this handles is the case of inodes
whose i_uid or i_gid are not mapped into the vfs. Most of the code
simply doesn't care but it is easy to confuse the inode writeback path
so no operation that could cause an inode write-back is permitted for
such inodes (aka only reads are allowed).
This set of changes starts out by cleaning up the code paths involved
in user namespace permirted mounts. Then when things are clean enough
adds code that cleanly sets s_user_ns. Then additional restrictions
are added that are possible now that the filesystem superblock
contains owner information.
These changes should not affect anyone in practice, but there are some
parts of these restrictions that are changes in behavior.
- Andy's restriction on suid executables that does not honor the
suid bit when the path is from another mount namespace (think
/proc/[pid]/fd/) or when the filesystem was mounted by a less
privileged user.
- The replacement of the user namespace implicit setting of MNT_NODEV
with implicitly setting SB_I_NODEV on the filesystem superblock
instead.
Using SB_I_NODEV is a stronger form that happens to make this state
user invisible. The user visibility can be managed but it caused
problems when it was introduced from applications reasonably
expecting mount flags to be what they were set to.
There is a little bit of work remaining before it is safe to support
mounting filesystems with backing store in user namespaces, beyond
what is in this set of changes.
- Verifying the mounter has permission to read/write the block device
during mount.
- Teaching the integrity modules IMA and EVM to handle filesystems
mounted with only user namespace root and to reduce trust in their
security xattrs accordingly.
- Capturing the mounters credentials and using that for permission
checks in d_automount and the like. (Given that overlayfs already
does this, and we need the work in d_automount it make sense to
generalize this case).
Furthermore there are a few changes that are on the wishlist:
- Get all filesystems supporting posix acls using the generic posix
acls so that posix_acl_fix_xattr_from_user and
posix_acl_fix_xattr_to_user may be removed. [Maintainability]
- Reducing the permission checks in places such as remount to allow
the superblock owner to perform them.
- Allowing the superblock owner to chown files with unmapped uids and
gids to something that is mapped so the files may be treated
normally.
I am not considering even obvious relaxations of permission checks
until it is clear there are no more corner cases that need to be
locked down and handled generically.
Many thanks to Seth Forshee who kept this code alive, and putting up
with me rewriting substantial portions of what he did to handle more
corner cases, and for his diligent testing and reviewing of my
changes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits)
fs: Call d_automount with the filesystems creds
fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns
evm: Translate user/group ids relative to s_user_ns when computing HMAC
dquot: For now explicitly don't support filesystems outside of init_user_ns
quota: Handle quota data stored in s_user_ns in quota_setxquota
quota: Ensure qids map to the filesystem
vfs: Don't create inodes with a uid or gid unknown to the vfs
vfs: Don't modify inodes with a uid or gid unknown to the vfs
cred: Reject inodes with invalid ids in set_create_file_as()
fs: Check for invalid i_uid in may_follow_link()
vfs: Verify acls are valid within superblock's s_user_ns.
userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS
fs: Refuse uid/gid changes which don't map into s_user_ns
selinux: Add support for unprivileged mounts from user namespaces
Smack: Handle labels consistently in untrusted mounts
Smack: Add support for unprivileged mounts from user namespaces
fs: Treat foreign mounts as nosuid
fs: Limit file caps to the user namespace of the super block
userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag
userns: Remove implicit MNT_NODEV fragility.
...
Pull vfs updates from Al Viro:
"Assorted cleanups and fixes.
Probably the most interesting part long-term is ->d_init() - that will
have a bunch of followups in (at least) ceph and lustre, but we'll
need to sort the barrier-related rules before it can get used for
really non-trivial stuff.
Another fun thing is the merge of ->d_iput() callers (dentry_iput()
and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
except the one in __d_lookup_lru())"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
fs/dcache.c: avoid soft-lockup in dput()
vfs: new d_init method
vfs: Update lookup_dcache() comment
bdev: get rid of ->bd_inodes
Remove last traces of ->sync_page
new helper: d_same_name()
dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
vfs: clean up documentation
vfs: document ->d_real()
vfs: merge .d_select_inode() into .d_real()
unify dentry_iput() and dentry_unlink_inode()
binfmt_misc: ->s_root is not going anywhere
drop redundant ->owner initializations
ufs: get rid of redundant checks
orangefs: constify inode_operations
missed comment updates from ->direct_IO() prototype change
file_inode(f)->i_mapping is f->f_mapping
trim fsnotify hooks a bit
9p: new helper - v9fs_parent_fid()
debugfs: ->d_parent is never NULL or negative
...
Currently, presence of direct_access() in block_device_operations
indicates support of DAX on its block device. Because
block_device_operations is instantiated with 'const', this DAX
capablity may not be enabled conditinally.
In preparation for supporting DAX to device-mapper devices, add
QUEUE_FLAG_DAX to request_queue flags to advertise their DAX
support. This will allow to set the DAX capability based on how
mapped device is composed.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <linux-s390@vger.kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since 2006 we have ->i_bdev pinning bdev in question, so there's no
way to get to bdev ->evict_inode() while there's an aliasing inode
anywhere. In other words, the only place walking the list of aliases
is guaranteed to do it only when the list is empty...
Remove the detritus; it should've been done in "[PATCH] Fix a race
condition between ->i_mapping and iput()", but nobody had noticed it
back then.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Introduce a function may_open_dev that tests MNT_NODEV and a new
superblock flab SB_I_NODEV. Use this new function in all of the
places where MNT_NODEV was previously tested.
Add the new SB_I_NODEV s_iflag to proc, sysfs, and mqueuefs as those
filesystems should never support device nodes, and a simple superblock
flags makes that very hard to get wrong. With SB_I_NODEV set if any
device nodes somehow manage to show up on on a filesystem those
device nodes will be unopenable.
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
- 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.
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Merge tag 'dax-misc-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
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
1/ Device DAX for persistent memory:
Device DAX is the device-centric analogue of Filesystem DAX
(CONFIG_FS_DAX). It allows memory ranges to be allocated and mapped
without need of an intervening file system. Device DAX is strict,
precise and predictable. Specifically this interface:
a) Guarantees fault granularity with respect to a given page size
(pte, pmd, or pud) set at configuration time.
b) Enforces deterministic behavior by being strict about what fault
scenarios are supported.
Persistent memory is the first target, but the mechanism is also
targeted for exclusive allocations of performance/feature differentiated
memory ranges.
2/ Support for the HPE DSM (device specific method) command formats.
This enables management of these first generation devices until a
unified DSM specification materializes.
3/ Further ACPI 6.1 compliance with support for the common dimm
identifier format.
4/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The bulk of this update was stabilized before the merge window and
appeared in -next. The "device dax" implementation was revised this
week in response to review feedback, and to address failures detected
by the recently expanded ndctl unit test suite.
Not included in this pull request are two dax topic branches (dax
error handling, and dax radix-tree locking). These topics were
deferred to get a few more days of -next integration testing, and to
coordinate a branch baseline with Ted and the ext4 tree. Vishal and
Ross will send the error handling and locking topics respectively in
the next few days.
This branch has received a positive build result from the kbuild robot
across 226 configs.
Summary:
- Device DAX for persistent memory: Device DAX is the device-centric
analogue of Filesystem DAX (CONFIG_FS_DAX). It allows memory
ranges to be allocated and mapped without need of an intervening
file system. Device DAX is strict, precise and predictable.
Specifically this interface:
a) Guarantees fault granularity with respect to a given page size
(pte, pmd, or pud) set at configuration time.
b) Enforces deterministic behavior by being strict about what
fault scenarios are supported.
Persistent memory is the first target, but the mechanism is also
targeted for exclusive allocations of performance/feature
differentiated memory ranges.
- Support for the HPE DSM (device specific method) command formats.
This enables management of these first generation devices until a
unified DSM specification materializes.
- Further ACPI 6.1 compliance with support for the common dimm
identifier format.
- Various fixes and cleanups across the subsystem"
* tag 'libnvdimm-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (40 commits)
libnvdimm, dax: fix deletion
libnvdimm, dax: fix alignment validation
libnvdimm, dax: autodetect support
libnvdimm: release ida resources
Revert "block: enable dax for raw block devices"
/dev/dax, core: file operations and dax-mmap
/dev/dax, pmem: direct access to persistent memory
libnvdimm: stop requiring a driver ->remove() method
libnvdimm, dax: record the specified alignment of a dax-device instance
libnvdimm, dax: reserve space to store labels for device-dax
libnvdimm, dax: introduce device-dax infrastructure
nfit: add sysfs dimm 'family' and 'dsm_mask' attributes
tools/testing/nvdimm: ND_CMD_CALL support
nfit: disable vendor specific commands
nfit: export subsystem ids as attributes
nfit: fix format interface code byte order per ACPI6.1
nfit, libnvdimm: limited/whitelisted dimm command marshaling mechanism
nfit, libnvdimm: clarify "commands" vs "_DSMs"
libnvdimm: increase max envelope size for ioctl
acpi/nfit: Add sysfs "id" for NVDIMM ID
...
This reverts commit 5a023cdba5.
The functionality is superseded by the new "Device DAX" facility.
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Jan Kara <jack@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
1/ If a mapping overlaps a bad sector fail the request.
2/ Do not opportunistically report more dax-capable capacity than is
requested when errors present.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
[vishal: fix a conflict with system RAM collision patches]
[vishal: add a 'size' parameter to ->direct_access]
[vishal: fix a conflict with DAX alignment check patches]
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
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 <toshi.kani@hpe.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@fb.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
DAX imposes additional requirements to a device. Add
bdev_dax_supported() which performs all the precondition checks
necessary for filesystem to mount the device with dax option.
Also add a new check to verify if a partition is aligned by 4KB.
When a partition is unaligned, any dax read/write access fails,
except for metadata update.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@fb.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
In preparation of moving DAX capability checks to the block layer
from filesystem code, add a VFS message interface that aligns with
filesystem's message format.
For instance, a vfs_msg() message followed by XFS messages in case
of a dax mount error may look like:
VFS (pmem0p1): error: unaligned partition for dax
XFS (pmem0p1): DAX unsupported by block device. Turning off DAX.
XFS (pmem0p1): Mounting V5 Filesystem
:
vfs_msg() is largely based on ext4_msg().
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <axboe@fb.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Fault handlers currently take complete_unwritten argument to convert
unwritten extents after PTEs are updated. However no filesystem uses
this anymore as the code is racy. Remove the unused argument.
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
The kiocb already has the new position, so use that. The only interesting
case is AIO, where we currently don't bother updating ki_pos. We're about
to free the kiocb after we're done, so we might as well update it to make
everyone's life simpler.
While we're at it also return the bytes written argument passed in if
we were successful so that the boilerplate error switch code in the
callers can go away.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This will allow us to do per-I/O sync file writes, as required by a lot
of fileservers or storage targets.
XXX: Will need a few additional audits for O_DSYNC
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually
work, so eliminate the superflous argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- 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 <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull core block updates from Jens Axboe:
"Here are the core block changes for this merge window. Not a lot of
exciting stuff going on in this round, most of the changes have been
on the driver side of things. That pull request is coming next. This
pull request contains:
- A set of fixes for chained bio handling from Christoph.
- A tag bounds check for blk-mq from Hannes, ensuring that we don't
do something stupid if a device reports an invalid tag value.
- A set of fixes/updates for the CFQ IO scheduler from Jan Kara.
- A set of blk-mq fixes from Keith, adding support for dynamic
hardware queues, and fixing init of max_dev_sectors for stacking
devices.
- A fix for the dynamic hw context from Ming.
- Enabling of cgroup writeback support on a block device, from
Shaohua"
* 'for-4.6/core' of git://git.kernel.dk/linux-block:
blk-mq: add bounds check on tag-to-rq conversion
block: bio_remaining_done() isn't unlikely
block: cleanup bio_endio
block: factor out chained bio completion
block: don't unecessarily clobber bi_error for chained bios
block-dev: enable writeback cgroup support
blk-mq: Fix NULL pointer updating nr_requests
blk-mq: mark request queue as mq asap
block: Initialize max_dev_sectors to 0
blk-mq: dynamic h/w context count
cfq-iosched: Allow parent cgroup to preempt its child
cfq-iosched: Allow sync noidle workloads to preempt each other
cfq-iosched: Reorder checks in cfq_should_preempt()
cfq-iosched: Don't group_idle if cfqq has big thinktime
block_dev's .writepages/.writepage already handles
wbc_init_bio/wbc_account_io. We only set the SB_I_CGROUPWB bit to
suppport writeback cgroup support.
Signed-off-by: Shaohua Li <shli@fb.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
Previously calls to dax_writeback_mapping_range() for all DAX filesystems
(ext2, ext4 & xfs) were centralized in filemap_write_and_wait_range().
dax_writeback_mapping_range() needs a struct block_device, and it used
to get that from inode->i_sb->s_bdev. This is correct for normal inodes
mounted on ext2, ext4 and XFS filesystems, but is incorrect for DAX raw
block devices and for XFS real-time files.
Instead, call dax_writeback_mapping_range() directly from the filesystem
->writepages function so that it can supply us with a valid block
device. This also fixes DAX code to properly flush caches in response
to sync(2).
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The recent *sync enabling discovered that we are inserting into the
block_device pagecache counter to the expectations of the dirty data
tracking for dax mappings. This can lead to data corruption.
We want to support DAX for block devices eventually, but it requires
wider changes to properly manage the pagecache.
dump_stack+0x85/0xc2
dax_writeback_mapping_range+0x60/0xe0
blkdev_writepages+0x3f/0x50
do_writepages+0x21/0x30
__filemap_fdatawrite_range+0xc6/0x100
filemap_write_and_wait+0x4a/0xa0
set_blocksize+0x70/0xd0
sb_set_blocksize+0x1d/0x50
ext4_fill_super+0x75b/0x3360
mount_bdev+0x180/0x1b0
ext4_mount+0x15/0x20
mount_fs+0x38/0x170
Mark the support broken so its disabled by default, but otherwise still
available for testing.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Suggested-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@fb.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previously the pfn_mkwrite() fault handler for raw block devices called
bldev_dax_fault() -> __dax_fault() to do a full DAX page fault.
Really what the pfn_mkwrite() fault handler needs to do is call
dax_pfn_mkwrite() to make sure that the radix tree entry for the given
PTE is marked as dirty so that a follow-up fsync or msync call will
flush it durably to media.
Fixes: 5a023cdba5 ("block: enable dax for raw block devices")
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <jack@suse.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull final vfs updates from Al Viro:
- The ->i_mutex wrappers (with small prereq in lustre)
- a fix for too early freeing of symlink bodies on shmem (they need to
be RCU-delayed) (-stable fodder)
- followup to dedupe stuff merged this cycle
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: abort dedupe loop if fatal signals are pending
make sure that freeing shmem fast symlinks is RCU-delayed
wrappers for ->i_mutex access
lustre: remove unused declaration
Add support for tracking dirty DAX entries in the struct address_space
radix tree. This tree is already used for dirty page writeback, and it
already supports the use of exceptional (non struct page*) entries.
In order to properly track dirty DAX pages we will insert new
exceptional entries into the radix tree that represent dirty DAX PTE or
PMD pages. These exceptional entries will also contain the writeback
addresses for the PTE or PMD faults that we can use at fsync/msync time.
There are currently two types of exceptional entries (shmem and shadow)
that can be placed into the radix tree, and this adds a third. We rely
on the fact that only one type of exceptional entry can be found in a
given radix tree based on its usage. This happens for free with DAX vs
shmem but we explicitly prevent shadow entries from being added to radix
trees for DAX mappings.
The only shadow entries that would be generated for DAX radix trees
would be to track zero page mappings that were created for holes. These
pages would receive minimal benefit from having shadow entries, and the
choice to have only one type of exceptional entry in a given radix tree
makes the logic simpler both in clear_exceptional_entry() and in the
rest of DAX.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jan Kara <jack@suse.com>
Cc: Jeff Layton <jlayton@poochiereds.net>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 <viro@zeniv.linux.org.uk>
Pull core block updates from Jens Axboe:
"We don't have a lot of core changes this time around, it's mostly in
drivers, which will come in a subsequent pull.
The cores changes include:
- blk-mq
- Prep patch from Christoph, changing blk_mq_alloc_request() to
take flags instead of just using gfp_t for sleep/nosleep.
- Doc patch from me, clarifying the difference between legacy
and blk-mq for timer usage.
- Fixes from Raghavendra for memory-less numa nodes, and a reuse
of CPU masks.
- Cleanup from Geliang Tang, using offset_in_page() instead of open
coding it.
- From Ilya, rename request_queue slab to it reflects what it holds,
and a fix for proper use of bdgrab/put.
- A real fix for the split across stripe boundaries from Keith. We
yanked a broken version of this from 4.4-rc final, this one works.
- From Mike Krinkin, emit a trace message when we split.
- From Wei Tang, two small cleanups, not explicitly clearing memory
that is already cleared"
* 'for-4.5/core' of git://git.kernel.dk/linux-block:
block: use bd{grab,put}() instead of open-coding
block: split bios to max possible length
block: add call to split trace point
blk-mq: Avoid memoryless numa node encoded in hctx numa_node
blk-mq: Reuse hardware context cpumask for tags
blk-mq: add a flags parameter to blk_mq_alloc_request
Revert "blk-flush: Queue through IO scheduler when flush not required"
block: clarify blk_add_timer() use case for blk-mq
bio: use offset_in_page macro
block: do not initialise statics to 0 or NULL
block: do not initialise globals to 0 or NULL
block: rename request_queue slab cache
The DAX implementation needs to protect new calls to ->direct_access()
and usage of its return value against the driver for the underlying
block device being disabled. Use blk_queue_enter()/blk_queue_exit() to
hold off blk_cleanup_queue() from proceeding, or otherwise fail new
mapping requests if the request_queue is being torn down.
This also introduces blk_dax_ctl to simplify the interface from fs/dax.c
through dax_map_atomic() to bdev_direct_access().
[willy@linux.intel.com: fix read() of a hole]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Jan Kara <jack@suse.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a ->direct_access() implementation ever returns a map count less than
PAGE_SIZE, catch the error in bdev_direct_access(). This simplifies
error checking in upper layers.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
bdev_write_page() is used by swapout and by writepage where we cannot
use __GFP_FS or __GFP_IO. So it is misleading to mention GFP_KERNEL
here.
blk_queue_enter() only actually looks at __GFP_DIRECT_RECLAIM, so no
bugs were harmed in the making of this patch.
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark those kmem allocations that are known to be easily triggered from
userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
memcg. For the list, see below:
- threadinfo
- task_struct
- task_delay_info
- pid
- cred
- mm_struct
- vm_area_struct and vm_region (nommu)
- anon_vma and anon_vma_chain
- signal_struct
- sighand_struct
- fs_struct
- files_struct
- fdtable and fdtable->full_fds_bits
- dentry and external_name
- inode for all filesystems. This is the most tedious part, because
most filesystems overwrite the alloc_inode method.
The list is far from complete, so feel free to add more objects.
Nevertheless, it should be close to "account everything" approach and
keep most workloads within bounds. Malevolent users will be able to
breach the limit, but this was possible even with the former "account
everything" approach (simply because it did not account everything in
fact).
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1/ Media error handling: The 'badblocks' implementation that originated
in md-raid is up-levelled to a generic capability of a block device.
This initial implementation is limited to being consulted in the pmem
block-i/o path. Later, 'badblocks' will be consulted when creating
dax mappings.
2/ Raw block device dax: For virtualization and other cases that want
large contiguous mappings of persistent memory, add the capability to
dax-mmap a block device directly.
3/ Increased /dev/mem restrictions: Add an option to treat all io-memory
as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access while a driver is
actively using an address range. This behavior is controlled via the
new CONFIG_IO_STRICT_DEVMEM option and can be overridden by the
existing "iomem=relaxed" kernel command line option.
4/ Miscellaneous fixes include a 'pfn'-device huge page alignment fix,
block device shutdown crash fix, and other small libnvdimm fixes.
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Merge tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"The bulk of this has appeared in -next and independently received a
build success notification from the kbuild robot. The 'for-4.5/block-
dax' topic branch was rebased over the weekend to drop the "block
device end-of-life" rework that Al would like to see re-implemented
with a notifier, and to address bug reports against the badblocks
integration.
There is pending feedback against "libnvdimm: Add a poison list and
export badblocks" received last week. Linda identified some localized
fixups that we will handle incrementally.
Summary:
- Media error handling: The 'badblocks' implementation that
originated in md-raid is up-levelled to a generic capability of a
block device. This initial implementation is limited to being
consulted in the pmem block-i/o path. Later, 'badblocks' will be
consulted when creating dax mappings.
- Raw block device dax: For virtualization and other cases that want
large contiguous mappings of persistent memory, add the capability
to dax-mmap a block device directly.
- Increased /dev/mem restrictions: Add an option to treat all
io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access
while a driver is actively using an address range. This behavior
is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be
overridden by the existing "iomem=relaxed" kernel command line
option.
- Miscellaneous fixes include a 'pfn'-device huge page alignment fix,
block device shutdown crash fix, and other small libnvdimm fixes"
* tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits)
block: kill disk_{check|set|clear|alloc}_badblocks
libnvdimm, pmem: nvdimm_read_bytes() badblocks support
pmem, dax: disable dax in the presence of bad blocks
pmem: fail io-requests to known bad blocks
libnvdimm: convert to statically allocated badblocks
libnvdimm: don't fail init for full badblocks list
block, badblocks: introduce devm_init_badblocks
block: clarify badblocks lifetime
badblocks: rename badblocks_free to badblocks_exit
libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h
libnvdimm: Add a poison list and export badblocks
nfit_test: Enable DSMs for all test NFITs
md: convert to use the generic badblocks code
block: Add badblock management for gendisks
badblocks: Add core badblock management code
block: fix del_gendisk() vs blkdev_ioctl crash
block: enable dax for raw block devices
block: introduce bdev_file_inode()
restrict /dev/mem to idle io memory ranges
arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug
...
- bd_acquire() and bd_forget() open-code bdgrab() and bdput()
- raw driver uses igrab() but never checks its return value and always
holds another ref from bind_set() while calling it, so it's
equivalent to bdgrab()
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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 <jmoyer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reviewed-by: Jan Kara <jack@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Similar to the file_inode() helper, provide a helper to lookup the inode for a
raw block device itself.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
gendisk with part==0 is obviously gendisk->disk_name.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Since 52ebea749a ("writeback: make backing_dev_info host
cgroup-specific bdi_writebacks") inode, at some point in its lifetime,
gets attached to a wb (struct bdi_writeback). Detaching happens on
evict, in inode_detach_wb() called from __destroy_inode(), and involves
updating wb.
However, detaching an internal bdev inode from its wb in
__destroy_inode() is too late. Its bdi and by extension root wb are
embedded into struct request_queue, which has different lifetime rules
and can be freed long before the final bdput() is called (can be from
__fput() of a corresponding /dev inode, through dput() - evict() -
bd_forget(). bdevs hold onto the underlying disk/queue pair only while
opened; as soon as bdev is closed all bets are off. In fact,
disk/queue can be gone before __blkdev_put() even returns:
1499 static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
1500 {
...
1518 if (bdev->bd_contains == bdev) {
1519 if (disk->fops->release)
1520 disk->fops->release(disk, mode);
[ Driver puts its references to disk/queue ]
1521 }
1522 if (!bdev->bd_openers) {
1523 struct module *owner = disk->fops->owner;
1524
1525 disk_put_part(bdev->bd_part);
1526 bdev->bd_part = NULL;
1527 bdev->bd_disk = NULL;
1528 if (bdev != bdev->bd_contains)
1529 victim = bdev->bd_contains;
1530 bdev->bd_contains = NULL;
1531
1532 put_disk(disk);
[ We put ours, the queue is gone
The last bdput() would result in a write to invalid memory ]
1533 module_put(owner);
...
1539 }
Since bdev inodes are special anyway, detach them in __blkdev_put()
after clearing inode's dirty bits, turning the problematic
inode_detach_wb() in __destroy_inode() into a noop.
add_disk() grabs its disk->queue since 523e1d399c ("block: make
gendisk hold a reference to its queue"), so the old ->release comment
is removed in favor of the new inode_detach_wb() comment.
Cc: stable@vger.kernel.org # 4.2+, needs backporting
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
We already have the reserved flag, and a nowait flag awkwardly encoded as
a gfp_t. Add a real flags argument to make the scheme more extensible and
allow for a nicer calling convention.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
If a block device is hot removed and later last reference to device
is put, we try to writeback the dirty inode. But device is gone and
that writeback fails.
Currently we do a WARN_ON() which does not seem to be the right thing.
Convert it to a ratelimited kernel warning.
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
[jmoyer@redhat.com: get rid of unnecessary name initialization, 80 cols]
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Up until now the_integrity profile has been dynamically allocated and
attached to struct gendisk after the disk has been made active.
This causes problems because NVMe devices need to register the profile
prior to the partition table being read due to a mandatory metadata
buffer requirement. In addition, DM goes through hoops to deal with
preallocating, but not initializing integrity profiles.
Since the integrity profile is small (4 bytes + a pointer), Christoph
suggested moving it to struct gendisk proper. This requires several
changes:
- Moving the blk_integrity definition to genhd.h.
- Inlining blk_integrity in struct gendisk.
- Removing the dynamic allocation code.
- Adding helper functions which allow gendisk to set up and tear down
the integrity sysfs dir when a disk is added/deleted.
- Adding a blk_integrity_revalidate() callback for updating the stable
pages bdi setting.
- The calls that depend on whether a device has an integrity profile or
not now key off of the bi->profile pointer.
- Simplifying the integrity support routines in DM (Mike Snitzer).
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reported-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The dax code doesn't currently support misaligned partitions,
so disable O_DIRECT via dax until such time as that support
materializes.
Cc: <stable@vger.kernel.org>
Suggested-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Merge second patch-bomb from Andrew Morton:
"Almost all of the rest of MM. There was an unusually large amount of
MM material this time"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (141 commits)
zpool: remove no-op module init/exit
mm: zbud: constify the zbud_ops
mm: zpool: constify the zpool_ops
mm: swap: zswap: maybe_preload & refactoring
zram: unify error reporting
zsmalloc: remove null check from destroy_handle_cache()
zsmalloc: do not take class lock in zs_shrinker_count()
zsmalloc: use class->pages_per_zspage
zsmalloc: consider ZS_ALMOST_FULL as migrate source
zsmalloc: partial page ordering within a fullness_list
zsmalloc: use shrinker to trigger auto-compaction
zsmalloc: account the number of compacted pages
zsmalloc/zram: introduce zs_pool_stats api
zsmalloc: cosmetic compaction code adjustments
zsmalloc: introduce zs_can_compact() function
zsmalloc: always keep per-class stats
zsmalloc: drop unused variable `nr_to_migrate'
mm/memblock.c: fix comment in __next_mem_range()
mm/page_alloc.c: fix type information of memoryless node
memory-hotplug: fix comments in zone_spanned_pages_in_node() and zone_spanned_pages_in_node()
...
In order to handle the !CONFIG_TRANSPARENT_HUGEPAGES case, we need to
return VM_FAULT_FALLBACK from the inlined dax_pmd_fault(), which is
defined in linux/mm.h. Given that we don't want to include <linux/mm.h>
in <linux/fs.h>, the easiest solution is to move the DAX-related
functions to a new header, <linux/dax.h>. We could also have moved
VM_FAULT_* definitions to a new header, or a different header that isn't
quite such a boil-the-ocean header as <linux/mm.h>, but this felt like
the best option.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1/ Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map. This facility is used by the pmem driver to
enable pfn_to_page() operations on the page frames returned by DAX
('direct_access' in 'struct block_device_operations'). For now, the
'memmap' allocation for these "device" pages comes from "System
RAM". Support for allocating the memmap from device memory will
arrive in a later kernel.
2/ Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3. Completion of
the conversion is targeted for v4.4.
3/ Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
4/ Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
5/ Miscellaneous updates and fixes to libnvdimm including support
for issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes.
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Merge tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
"This update has successfully completed a 0day-kbuild run and has
appeared in a linux-next release. The changes outside of the typical
drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
the introduction of ZONE_DEVICE + devm_memremap_pages().
Summary:
- Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map.
This facility is used by the pmem driver to enable pfn_to_page()
operations on the page frames returned by DAX ('direct_access' in
'struct block_device_operations').
For now, the 'memmap' allocation for these "device" pages comes
from "System RAM". Support for allocating the memmap from device
memory will arrive in a later kernel.
- Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3.
Completion of the conversion is targeted for v4.4.
- Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.
- Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.
- Miscellaneous updates and fixes to libnvdimm including support for
issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes"
* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
libnvdimm, pmem: direct map legacy pmem by default
libnvdimm, pmem: 'struct page' for pmem
libnvdimm, pfn: 'struct page' provider infrastructure
x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
add devm_memremap_pages
mm: ZONE_DEVICE for "device memory"
mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
dax: drop size parameter to ->direct_access()
nd_blk: change aperture mapping from WC to WB
nvdimm: change to use generic kvfree()
pmem, dax: have direct_access use __pmem annotation
dax: update I/O path to do proper PMEM flushing
pmem: add copy_from_iter_pmem() and clear_pmem()
pmem, x86: clean up conditional pmem includes
pmem: remove layer when calling arch_has_wmb_pmem()
pmem, x86: move x86 PMEM API to new pmem.h header
libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
pmem: switch to devm_ allocations
devres: add devm_memremap
libnvdimm, btt: write and validate parent_uuid
...
None of the implementations currently use it. The common
bdev_direct_access() entry point handles all the size checks before
calling ->direct_access().
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Update the annotation for the kaddr pointer returned by direct_access()
so that it is a __pmem pointer. This is consistent with the PMEM driver
and with how this direct_access() pointer is used in the DAX code.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The process of reducing contention on per-superblock inode lists
starts with moving the locking to match the per-superblock inode
list. This takes the global lock out of the picture and reduces the
contention problems to within a single filesystem. This doesn't get
rid of contention as the locks still have global CPU scope, but it
does isolate operations on different superblocks form each other.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dave Chinner <dchinner@redhat.com>
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
The brd driver is the only in-tree driver that may sleep currently.
After some discussion on linux-fsdevel, we decided that any driver
may choose to sleep in its ->direct_access method. To ensure that all
callers of bdev_direct_access() are prepared for this, add a call
to might_sleep().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If a block device supports the ->direct_access methods, bypass the normal
DIO path and use DAX to go straight to memcpy() instead of allocating
a DIO and a BIO.
Includes support for the DIO_SKIP_DIO_COUNT flag in DAX, as is done in
do_blockdev_direct_IO().
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more block layer patches from Jens Axboe:
"A few later arrivers that I didn't fold into the first pull request,
so we had a chance to run some testing. This contains:
- NVMe:
- Set of fixes from Keith
- 4.4 and earlier gcc build fix from Andrew
- small set of xen-blk{back,front} fixes from Bob Liu.
- warnings fix for bogus inline statement in I_BDEV() from Geert.
- error code fixup for SG_IO ioctl from Paolo Bonzini"
* 'for-linus' of git://git.kernel.dk/linux-block:
drivers/block/nvme-core.c: fix build with gcc-4.4.4
bdi: Remove "inline" keyword from exported I_BDEV() implementation
block: fix bogus EFAULT error from SG_IO ioctl
NVMe: Fix filesystem deadlock on removal
NVMe: Failed controller initialization fixes
NVMe: Unify controller probe and resume
NVMe: Don't use fake status on cancelled command
NVMe: Fix device cleanup on initialization failure
drivers: xen-blkfront: only talk_to_blkback() when in XenbusStateInitialising
xen/block: add multi-page ring support
driver: xen-blkfront: move talk_to_blkback to a more suitable place
drivers: xen-blkback: delay pending_req allocation to connect_ring
4 drivers / enabling modules:
NFIT:
Instantiates an "nvdimm bus" with the core and registers memory devices
(NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware Interface
table). After registering NVDIMMs the NFIT driver then registers
"region" devices. A libnvdimm-region defines an access mode and the
boundaries of persistent memory media. A region may span multiple
NVDIMMs that are interleaved by the hardware memory controller. In
turn, a libnvdimm-region can be carved into a "namespace" device and
bound to the PMEM or BLK driver which will attach a Linux block device
(disk) interface to the memory.
PMEM:
Initially merged in v4.1 this driver for contiguous spans of persistent
memory address ranges is re-worked to drive PMEM-namespaces emitted by
the libnvdimm-core. In this update the PMEM driver, on x86, gains the
ability to assert that writes to persistent memory have been flushed all
the way through the caches and buffers in the platform to persistent
media. See memcpy_to_pmem() and wmb_pmem().
BLK:
This new driver enables access to persistent memory media through "Block
Data Windows" as defined by the NFIT. The primary difference of this
driver to PMEM is that only a small window of persistent memory is
mapped into system address space at any given point in time. Per-NVDIMM
windows are reprogrammed at run time, per-I/O, to access different
portions of the media. BLK-mode, by definition, does not support DAX.
BTT:
This is a library, optionally consumed by either PMEM or BLK, that
converts a byte-accessible namespace into a disk with atomic sector
update semantics (prevents sector tearing on crash or power loss). The
sinister aspect of sector tearing is that most applications do not know
they have a atomic sector dependency. At least today's disk's rarely
ever tear sectors and if they do one almost certainly gets a CRC error
on access. NVDIMMs will always tear and always silently. Until an
application is audited to be robust in the presence of sector-tearing
the usage of BTT is recommended.
Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig,
Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox,
Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael
Wysocki, and Bob Moore.
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Merge tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm
Pull libnvdimm subsystem from Dan Williams:
"The libnvdimm sub-system introduces, in addition to the
libnvdimm-core, 4 drivers / enabling modules:
NFIT:
Instantiates an "nvdimm bus" with the core and registers memory
devices (NVDIMMs) enumerated by the ACPI 6.0 NFIT (NVDIMM Firmware
Interface table).
After registering NVDIMMs the NFIT driver then registers "region"
devices. A libnvdimm-region defines an access mode and the
boundaries of persistent memory media. A region may span multiple
NVDIMMs that are interleaved by the hardware memory controller. In
turn, a libnvdimm-region can be carved into a "namespace" device and
bound to the PMEM or BLK driver which will attach a Linux block
device (disk) interface to the memory.
PMEM:
Initially merged in v4.1 this driver for contiguous spans of
persistent memory address ranges is re-worked to drive
PMEM-namespaces emitted by the libnvdimm-core.
In this update the PMEM driver, on x86, gains the ability to assert
that writes to persistent memory have been flushed all the way
through the caches and buffers in the platform to persistent media.
See memcpy_to_pmem() and wmb_pmem().
BLK:
This new driver enables access to persistent memory media through
"Block Data Windows" as defined by the NFIT. The primary difference
of this driver to PMEM is that only a small window of persistent
memory is mapped into system address space at any given point in
time.
Per-NVDIMM windows are reprogrammed at run time, per-I/O, to access
different portions of the media. BLK-mode, by definition, does not
support DAX.
BTT:
This is a library, optionally consumed by either PMEM or BLK, that
converts a byte-accessible namespace into a disk with atomic sector
update semantics (prevents sector tearing on crash or power loss).
The sinister aspect of sector tearing is that most applications do
not know they have a atomic sector dependency. At least today's
disk's rarely ever tear sectors and if they do one almost certainly
gets a CRC error on access. NVDIMMs will always tear and always
silently. Until an application is audited to be robust in the
presence of sector-tearing the usage of BTT is recommended.
Thanks to: Ross Zwisler, Jeff Moyer, Vishal Verma, Christoph Hellwig,
Ingo Molnar, Neil Brown, Boaz Harrosh, Robert Elliott, Matthew Wilcox,
Andy Rudoff, Linda Knippers, Toshi Kani, Nicholas Moulin, Rafael
Wysocki, and Bob Moore"
* tag 'libnvdimm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm: (33 commits)
arch, x86: pmem api for ensuring durability of persistent memory updates
libnvdimm: Add sysfs numa_node to NVDIMM devices
libnvdimm: Set numa_node to NVDIMM devices
acpi: Add acpi_map_pxm_to_online_node()
libnvdimm, nfit: handle unarmed dimms, mark namespaces read-only
pmem: flag pmem block devices as non-rotational
libnvdimm: enable iostat
pmem: make_request cleanups
libnvdimm, pmem: fix up max_hw_sectors
libnvdimm, blk: add support for blk integrity
libnvdimm, btt: add support for blk integrity
fs/block_dev.c: skip rw_page if bdev has integrity
libnvdimm: Non-Volatile Devices
tools/testing/nvdimm: libnvdimm unit test infrastructure
libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory
nd_btt: atomic sector updates
libnvdimm: infrastructure for btt devices
libnvdimm: write blk label set
libnvdimm: write pmem label set
libnvdimm: blk labels and namespace instantiation
...
With gcc 3.4.6/4.1.2/4.2.4 (not with 4.4.7/4.6.4/4.8.4):
CC fs/block_dev.o
include/linux/fs.h:804: warning: ‘I_BDEV’ declared inline after being called
include/linux/fs.h:804: warning: previous declaration of ‘I_BDEV’ was here
Commit a212b105b0 ("bdi: make inode_to_bdi() inline") added a
caller of I_BDEV() in a header file, exposing the bogus "inline" on the
exported implementation.
Drop the "inline" keyword to fix this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
If a block device has bio integrity enabled, rw_page will bypass the
integrity payload, which is undesirable. Skip rw_page if this is the
case.
Currently brd and zram provide rw_page, and the proposed 'nd' drivers
will too.
Cc: Jens Axboe <axboe@fb.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Suggested-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that bdi definitions are moved to backing-dev-defs.h,
backing-dev.h can include blkdev.h and inline inode_to_bdi() without
worrying about introducing circular include dependency. The function
gets called from hot paths and fairly trivial.
This patch makes inode_to_bdi() and sb_is_blkdev_sb() that the
function calls inline. blockdev_superblock and noop_backing_dev_info
are EXPORT_GPL'd to allow the inline functions to be used from
modules.
While at it, make sb_is_blkdev_sb() return bool instead of int.
v2: Fixed typo in description as suggested by Jan.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.
This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it. c files
which need access to more backing-dev details now include
backing-dev.h directly. This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.
v2: fs/fat build failure fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
do_blockdev_direct_IO() increments and decrements the inode
->i_dio_count for each IO operation. It does this to protect against
truncate of a file. Block devices don't need this sort of protection.
For a capable multiqueue setup, this atomic int is the only shared
state between applications accessing the device for O_DIRECT, and it
presents a scaling wall for that. In my testing, as much as 30% of
system time is spent incrementing and decrementing this value. A mixed
read/write workload improved from ~2.5M IOPS to ~9.6M IOPS, with
better latencies too. Before:
clat percentiles (usec):
| 1.00th=[ 33], 5.00th=[ 34], 10.00th=[ 34], 20.00th=[ 34],
| 30.00th=[ 34], 40.00th=[ 34], 50.00th=[ 35], 60.00th=[ 35],
| 70.00th=[ 35], 80.00th=[ 35], 90.00th=[ 37], 95.00th=[ 80],
| 99.00th=[ 98], 99.50th=[ 151], 99.90th=[ 155], 99.95th=[ 155],
| 99.99th=[ 165]
After:
clat percentiles (usec):
| 1.00th=[ 95], 5.00th=[ 108], 10.00th=[ 129], 20.00th=[ 149],
| 30.00th=[ 155], 40.00th=[ 161], 50.00th=[ 167], 60.00th=[ 171],
| 70.00th=[ 177], 80.00th=[ 185], 90.00th=[ 201], 95.00th=[ 270],
| 99.00th=[ 390], 99.50th=[ 398], 99.90th=[ 418], 99.95th=[ 422],
| 99.99th=[ 438]
In other setups, Robert Elliott reported seeing good performance
improvements:
https://lkml.org/lkml/2015/4/3/557
The more applications accessing the device, the worse it gets.
Add a new direct-io flags, DIO_SKIP_DIO_COUNT, which tells
do_blockdev_direct_IO() that it need not worry about incrementing
or decrementing the inode i_dio_count for this caller.
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Elliott, Robert (Server Storage) <elliott@hp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Most filesystems call through to these at some point, so we'll start
here.
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull core block IO changes from Jens Axboe:
"This contains:
- A series from Christoph that cleans up and refactors various parts
of the REQ_BLOCK_PC handling. Contributions in that series from
Dongsu Park and Kent Overstreet as well.
- CFQ:
- A bug fix for cfq for realtime IO scheduling from Jeff Moyer.
- A stable patch fixing a potential crash in CFQ in OOM
situations. From Konstantin Khlebnikov.
- blk-mq:
- Add support for tag allocation policies, from Shaohua. This is
a prep patch enabling libata (and other SCSI parts) to use the
blk-mq tagging, instead of rolling their own.
- Various little tweaks from Keith and Mike, in preparation for
DM blk-mq support.
- Minor little fixes or tweaks from me.
- A double free error fix from Tony Battersby.
- The partition 4k issue fixes from Matthew and Boaz.
- Add support for zero+unprovision for blkdev_issue_zeroout() from
Martin"
* 'for-3.20/core' of git://git.kernel.dk/linux-block: (27 commits)
block: remove unused function blk_bio_map_sg
block: handle the null_mapped flag correctly in blk_rq_map_user_iov
blk-mq: fix double-free in error path
block: prevent request-to-request merging with gaps if not allowed
blk-mq: make blk_mq_run_queues() static
dm: fix multipath regression due to initializing wrong request
cfq-iosched: handle failure of cfq group allocation
block: Quiesce zeroout wrapper
block: rewrite and split __bio_copy_iov()
block: merge __bio_map_user_iov into bio_map_user_iov
block: merge __bio_map_kern into bio_map_kern
block: pass iov_iter to the BLOCK_PC mapping functions
block: add a helper to free bio bounce buffer pages
block: use blk_rq_map_user_iov to implement blk_rq_map_user
block: simplify bio_map_kern
block: mark blk-mq devices as stackable
block: keep established cmd_flags when cloning into a blk-mq request
block: add blk-mq support to blk_insert_cloned_request()
block: require blk_rq_prep_clone() be given an initialized clone request
blk-mq: add tag allocation policy
...
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since 018a17bdc8 ("bdi: reimplement bdev_inode_switch_bdi()") the
block device code writes out all dirty data whenever switching the
backing_dev_info for a block device inode. But a block device inode can
only be dirtied when it is in use, which means we only have to write it
out on the final blkdev_put, but not when doing a blkdev_get.
Factoring out the write out from the bdi list switch prepares from
removing the list switch later in the series.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
In order to support accesses to larger chunks of memory, pass in a
'size' parameter (counted in bytes), and return the amount available at
that address.
Add a new helper function, bdev_direct_access(), to handle common
functionality including partition handling, checking the length requested
is positive, checking for the sector being page-aligned, and checking
the length of the request does not pass the end of the partition.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently, freezing a filesystem involves calling freeze_super, which locks
sb->s_umount and then calls the fs-specific freeze_fs hook. This makes it
hard for gfs2 (and potentially other cluster filesystems) to use the vfs
freezing code to do freezes on all the cluster nodes.
In order to communicate that a freeze has been requested, and to make sure
that only one node is trying to freeze at a time, gfs2 uses a glock
(sd_freeze_gl). The problem is that there is no hook for gfs2 to acquire
this lock before calling freeze_super. This means that two nodes can
attempt to freeze the filesystem by both calling freeze_super, acquiring
the sb->s_umount lock, and then attempting to grab the cluster glock
sd_freeze_gl. Only one will succeed, and the other will be stuck in
freeze_super, making it impossible to finish freezing the node.
To solve this problem, this patch adds the freeze_super and thaw_super
hooks. If a filesystem implements these hooks, they are called instead of
the vfs freeze_super and thaw_super functions. This means that every
filesystem that implements these hooks must call the vfs freeze_super and
thaw_super functions itself within the hook function to make use of the vfs
freezing code.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Author: David Jeffery <djeffery@redhat.com>
Changes to the basic direct I/O code have broken the raw driver when reading
to the end of a raw device. Instead of returning a short read for a read that
extends partially beyond the device's end or 0 when at the end of the device,
these reads now return EIO.
The raw driver needs the same end of device handling as was added for normal
block devices. Using blkdev_read_iter, which has the needed size checks,
prevents the EIO conditions at the end of the device.
Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
Sequential read from a block device is expected to be equal or faster than
from the file on a filesystem. But it is not correct due to the lack of
effective readpages() in the address space operations for block device.
This implements readpages() operation for block device by using
mpage_readpages() which can create multipage BIOs instead of BIOs for each
page and reduce system CPU time consumption.
Install 1GB of RAM disk storage:
# modprobe scsi_debug dev_size_mb=1024 delay=0
Sequential read from file on a filesystem:
# mkfs.ext4 /dev/$DEV
# mount /dev/$DEV /mnt
# fio --name=t --size=512m --rw=read --filename=/mnt/file
...
read : io=524288KB, bw=2133.4MB/s, iops=546133, runt= 240msec
Sequential read from a block device:
# fio --name=t --size=512m --rw=read --filename=/dev/$DEV
...
(Without this commit)
read : io=524288KB, bw=1700.2MB/s, iops=435455, runt= 301msec
(With this commit)
read : io=524288KB, bw=2160.4MB/s, iops=553046, runt= 237msec
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A block_device may be attached to different gendisks and thus
different bdis over time. bdev_inode_switch_bdi() is used to switch
the associated bdi. The function assumes that the inode could be
dirty and transfers it between bdis if so. This is a bit nasty in
that it reaches into bdi internals.
This patch reimplements the function so that it writes out the inode
if dirty. This is a lot simpler and can be implemented without
exposing bdi internals.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
bdev_get_queue() returns the request_queue associated with the
specified block_device. blk_get_backing_dev_info() makes use of
bdev_get_queue() to determine the associated bdi given a block_device.
All the callers of bdev_get_queue() including
blk_get_backing_dev_info() assume that bdev_get_queue() may return
NULL and implement NULL handling; however, bdev_get_queue() requires
the passed in block_device is opened and attached to its gendisk.
Because an active gendisk always has a valid request_queue associated
with it, bdev_get_queue() can never return NULL and neither can
blk_get_backing_dev_info().
Make it clear that neither of the two functions can return NULL and
remove NULL handling from all the callers.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Mason <clm@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull vfs updates from Al Viro:
"This the bunch that sat in -next + lock_parent() fix. This is the
minimal set; there's more pending stuff.
In particular, I really hope to get acct.c fixes merged this cycle -
we need that to deal sanely with delayed-mntput stuff. In the next
pile, hopefully - that series is fairly short and localized
(kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more
iov_iter work. Most of prereqs for ->splice_write with sane locking
order are there and Kent's dio rewrite would also fit nicely on top of
this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
lock_parent: don't step on stale ->d_parent of all-but-freed one
kill generic_file_splice_write()
ceph: switch to iter_file_splice_write()
shmem: switch to iter_file_splice_write()
nfs: switch to iter_splice_write_file()
fs/splice.c: remove unneeded exports
ocfs2: switch to iter_file_splice_write()
->splice_write() via ->write_iter()
bio_vec-backed iov_iter
optimize copy_page_{to,from}_iter()
bury generic_file_aio_{read,write}
lustre: get rid of messing with iovecs
ceph: switch to ->write_iter()
ceph_sync_direct_write: stop poking into iov_iter guts
ceph_sync_read: stop poking into iov_iter guts
new helper: copy_page_from_iter()
fuse: switch to ->write_iter()
btrfs: switch to ->write_iter()
ocfs2: switch to ->write_iter()
xfs: switch to ->write_iter()
...
iter_file_splice_write() - a ->splice_write() instance that gathers the
pipe buffers, builds a bio_vec-based iov_iter covering those and feeds
it to ->write_iter(). A bunch of simple cases coverted to that...
[AV: fixed the braino spotted by Cyrill]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
A block device driver may choose to provide a rw_page operation. These
will be called when the filesystem is attempting to do page sized I/O to
page cache pages (ie not for direct I/O). This does preclude I/Os that
are larger than page size, so this may only be a performance gain for
some devices.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Tested-by: Dheeraj Reddy <dheeraj.reddy@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull vfs updates from Al Viro:
"The first vfs pile, with deep apologies for being very late in this
window.
Assorted cleanups and fixes, plus a large preparatory part of iov_iter
work. There's a lot more of that, but it'll probably go into the next
merge window - it *does* shape up nicely, removes a lot of
boilerplate, gets rid of locking inconsistencie between aio_write and
splice_write and I hope to get Kent's direct-io rewrite merged into
the same queue, but some of the stuff after this point is having
(mostly trivial) conflicts with the things already merged into
mainline and with some I want more testing.
This one passes LTP and xfstests without regressions, in addition to
usual beating. BTW, readahead02 in ltp syscalls testsuite has started
giving failures since "mm/readahead.c: fix readahead failure for
memoryless NUMA nodes and limit readahead pages" - might be a false
positive, might be a real regression..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
missing bits of "splice: fix racy pipe->buffers uses"
cifs: fix the race in cifs_writev()
ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
kill generic_file_buffered_write()
ocfs2_file_aio_write(): switch to generic_perform_write()
ceph_aio_write(): switch to generic_perform_write()
xfs_file_buffered_aio_write(): switch to generic_perform_write()
export generic_perform_write(), start getting rid of generic_file_buffer_write()
generic_file_direct_write(): get rid of ppos argument
btrfs_file_aio_write(): get rid of ppos
kill the 5th argument of generic_file_buffered_write()
kill the 4th argument of __generic_file_aio_write()
lustre: don't open-code kernel_recvmsg()
ocfs2: don't open-code kernel_recvmsg()
drbd: don't open-code kernel_recvmsg()
constify blk_rq_map_user_iov() and friends
lustre: switch to kernel_sendmsg()
ocfs2: don't open-code kernel_sendmsg()
take iov_iter stuff to mm/iov_iter.c
process_vm_access: tidy up a bit
...
