We can't dereference the dio structure after submitting the last bio for
this request, as I/O completion might have happened before the code is
run. Introduce a local is_sync variable instead.
Fixes: 542ff7bf ("block: new direct I/O implementation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Matias Bjørling <m@bjorling.me>
Tested-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull block layer fixes from Jens Axboe:
"A set of fixes for the current series, one fixing a regression with
block size < page cache size in the alias series from Jan. Outside of
that, two small cleanups for wbt from Bart, a nvme pull request from
Christoph, and a few small fixes of documentation updates"
* 'for-linus' of git://git.kernel.dk/linux-block:
block: fix up io_poll documentation
block: Avoid that sparse complains about context imbalance in __wbt_wait()
block: Make wbt_wait() definition consistent with declaration
clean_bdev_aliases: Prevent cleaning blocks that are not in block range
genhd: remove dead and duplicated scsi code
block: add back plugging in __blkdev_direct_IO
nvmet/fcloop: remove some logically dead code performing redundant ret checks
nvmet: fix KATO offset in Set Features
nvme/fc: simplify error handling of nvme_fc_create_hw_io_queues
nvme/fc: correct some printk information
nvme/scsi: Remove START STOP emulation
nvme/pci: Delete misleading queue-wrap comment
nvme/pci: Fix whitespace problem
nvme: simplify stripe quirk
nvme: update maintainers information
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows sending larger than 1 MB requests to devices that support
large I/O sizes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
For sync direct IO, generic_file_direct_write/generic_file_read_iter
will update file access position. Don't duplicate the update in
.direct_IO. This cause my raid array can't assemble.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
bdev->bd_contains is not stable before calling __blkdev_get().
When __blkdev_get() is called on a parition with ->bd_openers == 0
it sets
bdev->bd_contains = bdev;
which is not correct for a partition.
After a call to __blkdev_get() succeeds, ->bd_openers will be > 0
and then ->bd_contains is stable.
When FMODE_EXCL is used, blkdev_get() calls
bd_start_claiming() -> bd_prepare_to_claim() -> bd_may_claim()
This call happens before __blkdev_get() is called, so ->bd_contains
is not stable. So bd_may_claim() cannot safely use ->bd_contains.
It currently tries to use it, and this can lead to a BUG_ON().
This happens when a whole device is already open with a bd_holder (in
use by dm in my particular example) and two threads race to open a
partition of that device for the first time, one opening with O_EXCL and
one without.
The thread that doesn't use O_EXCL gets through blkdev_get() to
__blkdev_get(), gains the ->bd_mutex, and sets bdev->bd_contains = bdev;
Immediately thereafter the other thread, using FMODE_EXCL, calls
bd_start_claiming() from blkdev_get(). This should fail because the
whole device has a holder, but because bdev->bd_contains == bdev
bd_may_claim() incorrectly reports success.
This thread continues and blocks on bd_mutex.
The first thread then sets bdev->bd_contains correctly and drops the mutex.
The thread using FMODE_EXCL then continues and when it calls bd_may_claim()
again in:
BUG_ON(!bd_may_claim(bdev, whole, holder));
The BUG_ON fires.
Fix this by removing the dependency on ->bd_contains in
bd_may_claim(). As bd_may_claim() has direct access to the whole
device, it can simply test if the target bdev is the whole device.
Fixes: 6b4517a791 ("block: implement bd_claiming and claiming block")
Cc: stable@vger.kernel.org (v2.6.35+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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>
Christoph Hellwig