Commit Graph

66253 Commits

Author SHA1 Message Date
Miklos Szeredi 413daa1a3f fuse: connection remove fix
Re-add lost removal of fc from fuse_conn_list and the control filesystem.

Reported-by: kernel test robot <rong.a.chen@intel.com>
Fixes: fcee216beb ("fuse: split fuse_mount off of fuse_conn")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-10-12 10:28:14 +02:00
Max Reitz bf109c6404 fuse: implement crossmounts
FUSE servers can indicate crossmount points by setting FUSE_ATTR_SUBMOUNT
in fuse_attr.flags.  The inode will then be marked as S_AUTOMOUNT, and the
.d_automount implementation creates a new submount at that location, so
that the submount gets a distinct st_dev value.

Note that all submounts get a distinct superblock and a distinct st_dev
value, so for virtio-fs, even if the same filesystem is mounted more than
once on the host, none of its mount points will have the same st_dev.  We
need distinct superblocks because the superblock points to the root node,
but the different host mounts may show different trees (e.g. due to
submounts in some of them, but not in others).

Right now, this behavior is only enabled when fuse_conn.auto_submounts is
set, which is the case only for virtio-fs.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-10-09 16:33:47 +02:00
Max Reitz 1866d779d5 fuse: Allow fuse_fill_super_common() for submounts
Submounts have their own superblock, which needs to be initialized.
However, they do not have a fuse_fs_context associated with them, and
the root node's attributes should be taken from the mountpoint's node.

Extend fuse_fill_super_common() to work for submounts by making the @ctx
parameter optional, and by adding a @submount_finode parameter.

(There is a plain "unsigned" in an existing code block that is being
indented by this commit.  Extend it to "unsigned int" so checkpatch does
not complain.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 15:17:41 +02:00
Max Reitz fcee216beb fuse: split fuse_mount off of fuse_conn
We want to allow submounts for the same fuse_conn, but with different
superblocks so that each of the submounts has its own device ID.  To do
so, we need to split all mount-specific information off of fuse_conn
into a new fuse_mount structure, so that multiple mounts can share a
single fuse_conn.

We need to take care only to perform connection-level actions once (i.e.
when the fuse_conn and thus the first fuse_mount are established, or
when the last fuse_mount and thus the fuse_conn are destroyed).  For
example, fuse_sb_destroy() must invoke fuse_send_destroy() until the
last superblock is released.

To do so, we keep track of which fuse_mount is the root mount and
perform all fuse_conn-level actions only when this fuse_mount is
involved.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 15:17:41 +02:00
Max Reitz 8f622e9497 fuse: drop fuse_conn parameter where possible
With the last commit, all functions that handle some existing fuse_req
no longer need to be given the associated fuse_conn, because they can
get it from the fuse_req object.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 15:17:41 +02:00
Max Reitz 24754db272 fuse: store fuse_conn in fuse_req
Every fuse_req belongs to a fuse_conn.  Right now, we always know which
fuse_conn that is based on the respective device, but we want to allow
multiple (sub)mounts per single connection, and then the corresponding
filesystem is not going to be so trivial to obtain.

Storing a pointer to the associated fuse_conn in every fuse_req will
allow us to trivially find any request's superblock (and thus
filesystem) even then.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 15:17:40 +02:00
Miklos Szeredi d78092e493 fuse: fix page dereference after free
After unlock_request() pages from the ap->pages[] array may be put (e.g. by
aborting the connection) and the pages can be freed.

Prevent use after free by grabbing a reference to the page before calling
unlock_request().

The original patch was created by Pradeep P V K.

Reported-by: Pradeep P V K <ppvk@codeaurora.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-18 10:36:50 +02:00
Vivek Goyal 9a752d18c8 virtiofs: add logic to free up a memory range
Add logic to free up a busy memory range. Freed memory range will be
returned to free pool. Add a worker which can be started to select
and free some busy memory ranges.

Process can also steal one of its busy dax ranges if free range is not
available. I will refer it to as direct reclaim.

If free range is not available and nothing can't be stolen from same
inode, caller waits on a waitq for free range to become available.

For reclaiming a range, as of now we need to hold following locks in
specified order.

	down_write(&fi->i_mmap_sem);
	down_write(&fi->dax->sem);

We look for a free range in following order.

A. Try to get a free range.
B. If not, try direct reclaim.
C. If not, wait for a memory range to become free

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Vivek Goyal d0cfb9dcbc virtiofs: maintain a list of busy elements
This list will be used selecting fuse_dax_mapping to free when number of
free mappings drops below a threshold.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Vivek Goyal 6ae330cad6 virtiofs: serialize truncate/punch_hole and dax fault path
Currently in fuse we don't seem have any lock which can serialize fault
path with truncate/punch_hole path. With dax support I need one for
following reasons.

1. Dax requirement

  DAX fault code relies on inode size being stable for the duration of
  fault and want to serialize with truncate/punch_hole and they explicitly
  mention it.

  static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
                               const struct iomap_ops *ops)
        /*
         * Check whether offset isn't beyond end of file now. Caller is
         * supposed to hold locks serializing us with truncate / punch hole so
         * this is a reliable test.
         */
        max_pgoff = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);

2. Make sure there are no users of pages being truncated/punch_hole

  get_user_pages() might take references to page and then do some DMA
  to said pages. Filesystem might truncate those pages without knowing
  that a DMA is in progress or some I/O is in progress. So use
  dax_layout_busy_page() to make sure there are no such references
  and I/O is not in progress on said pages before moving ahead with
  truncation.

3. Limitation of kvm page fault error reporting

  If we are truncating file on host first and then removing mappings in
  guest lateter (truncate page cache etc), then this could lead to a
  problem with KVM. Say a mapping is in place in guest and truncation
  happens on host. Now if guest accesses that mapping, then host will
  take a fault and kvm will either exit to qemu or spin infinitely.

  IOW, before we do truncation on host, we need to make sure that guest
  inode does not have any mapping in that region or whole file.

4. virtiofs memory range reclaim

 Soon I will introduce the notion of being able to reclaim dax memory
 ranges from a fuse dax inode. There also I need to make sure that
 no I/O or fault is going on in the reclaimed range and nobody is using
 it so that range can be reclaimed without issues.

Currently if we take inode lock, that serializes read/write. But it does
not do anything for faults. So I add another semaphore fuse_inode->i_mmap_sem
for this purpose.  It can be used to serialize with faults.

As of now, I am adding taking this semaphore only in dax fault path and
not regular fault path because existing code does not have one. May
be existing code can benefit from it as well to take care of some
races, but that we can fix later if need be. For now, I am just focussing
only on DAX path which is new path.

Also added logic to take fuse_inode->i_mmap_sem in
truncate/punch_hole/open(O_TRUNC) path to make sure file truncation and
fuse dax fault are mutually exlusive and avoid all the above problems.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Vivek Goyal 9483e7d580 virtiofs: define dax address space operations
This is done along the lines of ext4 and xfs.  I primarily wanted
->writepages hook at this time so that I could call into
dax_writeback_mapping_range().  This in turn will decide which pfns need to
be written back.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Stefan Hajnoczi 2a9a609a0c virtiofs: add DAX mmap support
Add DAX mmap() support.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Vivek Goyal c2d0ad00d9 virtiofs: implement dax read/write operations
This patch implements basic DAX support. mmap() is not implemented
yet and will come in later patches. This patch looks into implemeting
read/write.

We make use of interval tree to keep track of per inode dax mappings.

Do not use dax for file extending writes, instead just send WRITE message
to daemon (like we do for direct I/O path). This will keep write and
i_size change atomic w.r.t crash.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Peng Tao <tao.peng@linux.alibaba.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:23 +02:00
Stefan Hajnoczi fd1a1dc6f5 virtiofs: implement FUSE_INIT map_alignment field
The device communicates FUSE_SETUPMAPPING/FUSE_REMOVMAPPING alignment
constraints via the FUST_INIT map_alignment field.  Parse this field and
ensure our DAX mappings meet the alignment constraints.

We don't actually align anything differently since our mappings are
already 2MB aligned.  Just check the value when the connection is
established.  If it becomes necessary to honor arbitrary alignments in
the future we'll have to adjust how mappings are sized.

The upshot of this commit is that we can be confident that mappings will
work even when emulating x86 on Power and similar combinations where the
host page sizes are different.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Vivek Goyal 45f2348ece virtiofs: keep a list of free dax memory ranges
Divide the dax memory range into fixed size ranges (2MB for now) and put
them in a list. This will track free ranges. Once an inode requires a
free range, we will take one from here and put it in interval-tree
of ranges assigned to inode.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Peng Tao <tao.peng@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Vivek Goyal 1dd539577c virtiofs: add a mount option to enable dax
Add a mount option to allow using dax with virtio_fs.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Stefan Hajnoczi 22f3787e9d virtiofs: set up virtio_fs dax_device
Setup a dax device.

Use the shm capability to find the cache entry and map it.

The DAX window is accessed by the fs/dax.c infrastructure and must have
struct pages (at least on x86).  Use devm_memremap_pages() to map the
DAX window PCI BAR and allocate struct page.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Vivek Goyal f4fd4ae354 virtiofs: get rid of no_mount_options
This option was introduced so that for virtio_fs we don't show any mounts
options fuse_show_options(). Because we don't offer any of these options
to be controlled by mounter.

Very soon we are planning to introduce option "dax" which mounter should
be able to specify. And no_mount_options does not work anymore.


Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Vivek Goyal b43b7e81eb virtiofs: provide a helper function for virtqueue initialization
This reduces code duplication and make it little easier to read code.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
Vivek Goyal 6bbdd563ee dax: Create a range version of dax_layout_busy_page()
virtiofs device has a range of memory which is mapped into file inodes
using dax. This memory is mapped in qemu on host and maps different
sections of real file on host. Size of this memory is limited
(determined by administrator) and depending on filesystem size, we will
soon reach a situation where all the memory is in use and we need to
reclaim some.

As part of reclaim process, we will need to make sure that there are
no active references to pages (taken by get_user_pages()) on the memory
range we are trying to reclaim. I am planning to use
dax_layout_busy_page() for this. But in current form this is per inode
and scans through all the pages of the inode.

We want to reclaim only a portion of memory (say 2MB page). So we want
to make sure that only that 2MB range of pages do not have any
references  (and don't want to unmap all the pages of inode).

Hence, create a range version of this function named
dax_layout_busy_page_range() which can be used to pass a range which
needs to be unmapped.

Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-nvdimm@lists.01.org
Cc: Jan Kara <jack@suse.cz>
Cc: Vishal L Verma <vishal.l.verma@intel.com>
Cc: "Weiny, Ira" <ira.weiny@intel.com>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-10 11:39:22 +02:00
André Almeida c1b0c62715 fuse: update project homepage
As stated in https://sourceforge.net/projects/fuse/, "the FUSE project has
moved to https://github.com/libfuse/" in 22-Dec-2015. Update URLs to
reflect this.

Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-09-04 11:32:10 +02:00
Linus Torvalds 3edd8db2d5 DFS SMB1 Fix
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Merge tag '5.9-rc2-smb-fix' of git://git.samba.org/sfrench/cifs-2.6

Pull cfis fix from Steve French:
 "DFS fix for referral problem when using SMB1"

* tag '5.9-rc2-smb-fix' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix check of tcon dfs in smb1
2020-08-30 11:38:21 -07:00
Linus Torvalds 1127b219ce fallthrough fixes for 5.9-rc3
Hi Linus,
 
 Please, pull the following patches that fix some minor issues introduced
 by the recent treewide fallthrough conversions:
 
 - Fix identation issue.
 - Fix erroneous fallthrough annotation.
 - Remove unnecessary fallthrough annotation.
 - Fix code comment changed by fallthrough conversion.
 
 Thanks
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Merge tag 'fallthrough-fixes-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull fallthrough fixes from Gustavo A. R. Silva:
 "Fix some minor issues introduced by the recent treewide fallthrough
  conversions:

   - Fix identation issue

   - Fix erroneous fallthrough annotation

   - Remove unnecessary fallthrough annotation

   - Fix code comment changed by fallthrough conversion"

* tag 'fallthrough-fixes-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  arm64/cpuinfo: Remove unnecessary fallthrough annotation
  media: dib0700: Fix identation issue in dib8096_set_param_override()
  afs: Remove erroneous fallthough annotation
  iio: dpot-dac: fix code comment in dpot_dac_read_raw()
2020-08-29 14:21:58 -07:00
Linus Torvalds 24148d8648 io_uring-5.9-2020-08-28
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Merge tag 'io_uring-5.9-2020-08-28' of git://git.kernel.dk/linux-block

Pull io_uring fixes from Jens Axboe:
 "A few fixes in here, all based on reports and test cases from folks
  using it. Most of it is stable material as well:

   - Hashed work cancelation fix (Pavel)

   - poll wakeup signalfd fix

   - memlock accounting fix

   - nonblocking poll retry fix

   - ensure we never return -ERESTARTSYS for reads

   - ensure offset == -1 is consistent with preadv2() as documented

   - IOPOLL -EAGAIN handling fixes

   - remove useless task_work bounce for block based -EAGAIN retry"

* tag 'io_uring-5.9-2020-08-28' of git://git.kernel.dk/linux-block:
  io_uring: don't bounce block based -EAGAIN retry off task_work
  io_uring: fix IOPOLL -EAGAIN retries
  io_uring: clear req->result on IOPOLL re-issue
  io_uring: make offset == -1 consistent with preadv2/pwritev2
  io_uring: ensure read requests go through -ERESTART* transformation
  io_uring: don't use poll handler if file can't be nonblocking read/written
  io_uring: fix imbalanced sqo_mm accounting
  io_uring: revert consumed iov_iter bytes on error
  io-wq: fix hang after cancelling pending hashed work
  io_uring: don't recurse on tsk->sighand->siglock with signalfd
2020-08-28 16:23:16 -07:00
Linus Torvalds e309428590 \n
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Merge tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull writeback fixes from Jan Kara:
 "Fixes for writeback code occasionally skipping writeback of some
  inodes or livelocking sync(2)"

* tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  writeback: Drop I_DIRTY_TIME_EXPIRE
  writeback: Fix sync livelock due to b_dirty_time processing
  writeback: Avoid skipping inode writeback
  writeback: Protect inode->i_io_list with inode->i_lock
2020-08-28 10:57:14 -07:00
Linus Torvalds 40129b8cb4 Fix memory leak on filesystem withdraw
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Merge tag 'gfs2-v5.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 fix from Andreas Gruenbacher:
 "Fix a memory leak on filesystem withdraw.

  We didn't detect this bug because we have slab merging on by default
  (CONFIG_SLAB_MERGE_DEFAULT). Adding 'slub_nomerge' to the kernel
  command line exposed the problem"

* tag 'gfs2-v5.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: add some much needed cleanup for log flushes that fail
2020-08-28 10:41:00 -07:00
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a 64-bit architecture with a 32-bit ino_t, a patch to disallow leases
 to avoid potential data integrity issues when CephFS is re-exported
 via NFS or CIFS and a fix for the bulk of W=1 compilation warnings.
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Merge tag 'ceph-for-5.9-rc3' of git://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "We have an inode number handling change, prompted by s390x which is a
  64-bit architecture with a 32-bit ino_t, a patch to disallow leases to
  avoid potential data integrity issues when CephFS is re-exported via
  NFS or CIFS and a fix for the bulk of W=1 compilation warnings"

* tag 'ceph-for-5.9-rc3' of git://github.com/ceph/ceph-client:
  ceph: don't allow setlease on cephfs
  ceph: fix inode number handling on arches with 32-bit ino_t
  libceph: add __maybe_unused to DEFINE_CEPH_FEATURE
2020-08-28 10:33:04 -07:00
Paulo Alcantara e183785f25 cifs: fix check of tcon dfs in smb1
For SMB1, the DFS flag should be checked against tcon->Flags rather
than tcon->share_flags.  While at it, add an is_tcon_dfs() helper to
check for DFS capability in a more generic way.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
2020-08-28 12:27:33 -05:00
Jens Axboe fdee946d09 io_uring: don't bounce block based -EAGAIN retry off task_work
These events happen inline from submission, so there's no need to
bounce them through the original task. Just set them up for retry
and issue retry directly instead of going over task_work.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-27 16:48:34 -06:00
Jens Axboe eefdf30f3d io_uring: fix IOPOLL -EAGAIN retries
This normally isn't hit, as polling is mostly done on NVMe with deep
queue depths. But if we do run into request starvation, we need to
ensure that retries are properly serialized.

Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-27 16:40:29 -06:00
Dan Carpenter 210e799ed2 afs: Remove erroneous fallthough annotation
The fall through annotation comes after a return statement so it's not
reachable.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-27 14:33:01 -05:00
Jens Axboe 56450c20fe io_uring: clear req->result on IOPOLL re-issue
Make sure we clear req->result, which was set to -EAGAIN for retry
purposes, when moving it to the reissue list. Otherwise we can end up
retrying a request more than once, which leads to weird results in
the io-wq handling (and other spots).

Cc: stable@vger.kernel.org
Reported-by: Andres Freund <andres@anarazel.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-26 18:58:26 -06:00
Jens Axboe 0fef948363 io_uring: make offset == -1 consistent with preadv2/pwritev2
The man page for io_uring generally claims were consistent with what
preadv2 and pwritev2 accept, but turns out there's a slight discrepancy
in how offset == -1 is handled for pipes/streams. preadv doesn't allow
it, but preadv2 does. This currently causes io_uring to return -EINVAL
if that is attempted, but we should allow that as documented.

This change makes us consistent with preadv2/pwritev2 for just passing
in a NULL ppos for streams if the offset is -1.

Cc: stable@vger.kernel.org # v5.7+
Reported-by: Benedikt Ames <wisp3rwind@posteo.eu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-26 10:36:20 -06:00
Linus Torvalds 2ac69819ba Fixes:
- Eliminate an oops introduced in v5.8
 - Remove a duplicate #include added by nfsd-5.9
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Merge tag 'nfsd-5.9-1' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull nfs server fixes from Chuck Lever:

 - Eliminate an oops introduced in v5.8

 - Remove a duplicate #include added by nfsd-5.9

* tag 'nfsd-5.9-1' of git://git.linux-nfs.org/projects/cel/cel-2.6:
  SUNRPC: remove duplicate include
  nfsd: fix oops on mixed NFSv4/NFSv3 client access
2020-08-25 18:01:36 -07:00
Linus Torvalds abb3438d69 m68knommu: fixes for 5.9-rc3
Fixes include:
 . revert binfmt_flat data offset removal
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Merge tag 'm68knommu-for-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu

Pull m68knommu fix from Greg Ungerer:
 "Only a single fix for the binfmt_flat loader (reverting a recent
  change)"

* tag 'm68knommu-for-v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  binfmt_flat: revert "binfmt_flat: don't offset the data start"
2020-08-25 11:59:23 -07:00
Jens Axboe 00d23d516e io_uring: ensure read requests go through -ERESTART* transformation
We need to call kiocb_done() for any ret < 0 to ensure that we always
get the proper -ERESTARTSYS (and friends) transformation done.

At some point this should be tied into general error handling, so we
can get rid of the various (mostly network) related commands that check
and perform this substitution.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-25 12:59:22 -06:00
Jens Axboe 9dab14b818 io_uring: don't use poll handler if file can't be nonblocking read/written
There's no point in using the poll handler if we can't do a nonblocking
IO attempt of the operation, since we'll need to go async anyway. In
fact this is actively harmful, as reading from eg pipes won't return 0
to indicate EOF.

Cc: stable@vger.kernel.org # v5.7+
Reported-by: Benedikt Ames <wisp3rwind@posteo.eu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-25 12:27:50 -06:00
Jens Axboe 6b7898eb18 io_uring: fix imbalanced sqo_mm accounting
We do the initial accounting of locked_vm and pinned_vm before we have
setup ctx->sqo_mm, which means we can end up having not accounted the
memory at setup time, but still decrement it when we exit. This causes
an imbalance in the accounting.

Setup ctx->sqo_mm earlier in io_uring_create(), before we do the first
accounting of mm->{locked,pinned}_vm. This also unifies the state
grabbing for the ctx, and eliminates a failure case in
io_sq_offload_start().

Fixes: f74441e631 ("io_uring: account locked memory before potential error case")
Reported-by: Robert M. Muncrief <rmuncrief@humanavance.com>
Reported-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Robert M. Muncrief <rmuncrief@humanavance.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-25 12:05:57 -06:00
Jens Axboe 842163154b io_uring: revert consumed iov_iter bytes on error
Some consumers of the iov_iter will return an error, but still have
bytes consumed in the iterator. This is an issue for -EAGAIN, since we
rely on a sane iov_iter state across retries.

Fix this by ensuring that we revert consumed bytes, if any, if the file
operations have consumed any bytes from iterator. This is similar to what
generic_file_read_iter() does, and is always safe as we have the previous
bytes count handy already.

Fixes: ff6165b2d7 ("io_uring: retain iov_iter state over io_read/io_write calls")
Reported-by: Dmitry Shulyak <yashulyak@gmail.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-25 07:28:43 -06:00
Linus Torvalds 9907ab3714 for-5.9-rc2-tag
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Merge tag 'for-5.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - fix swapfile activation on subvolumes with deleted snapshots

 - error value mixup when removing directory entries from tree log

 - fix lzo compression level reset after previous level setting

 - fix space cache memory leak after transaction abort

 - fix const function attribute

 - more error handling improvements

* tag 'for-5.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: detect nocow for swap after snapshot delete
  btrfs: check the right error variable in btrfs_del_dir_entries_in_log
  btrfs: fix space cache memory leak after transaction abort
  btrfs: use the correct const function attribute for btrfs_get_num_csums
  btrfs: reset compression level for lzo on remount
  btrfs: handle errors from async submission
2020-08-24 12:01:20 -07:00
Jeff Layton 496ceaf124 ceph: don't allow setlease on cephfs
Leases don't currently work correctly on kcephfs, as they are not broken
when caps are revoked. They could eventually be implemented similarly to
how we did them in libcephfs, but for now don't allow them.

[ idryomov: no need for simple_nosetlease() in ceph_dir_fops and
  ceph_snapdir_fops ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-08-24 20:06:54 +02:00
Jeff Layton ebce3eb2f7 ceph: fix inode number handling on arches with 32-bit ino_t
Tuan and Ulrich mentioned that they were hitting a problem on s390x,
which has a 32-bit ino_t value, even though it's a 64-bit arch (for
historical reasons).

I think the current handling of inode numbers in the ceph driver is
wrong. It tries to use 32-bit inode numbers on 32-bit arches, but that's
actually not a problem. 32-bit arches can deal with 64-bit inode numbers
just fine when userland code is compiled with LFS support (the common
case these days).

What we really want to do is just use 64-bit numbers everywhere, unless
someone has mounted with the ino32 mount option. In that case, we want
to ensure that we hash the inode number down to something that will fit
in 32 bits before presenting the value to userland.

Add new helper functions that do this, and only do the conversion before
presenting these values to userland in getattr and readdir.

The inode table hashvalue is changed to just cast the inode number to
unsigned long, as low-order bits are the most likely to vary anyway.

While it's not strictly required, we do want to put something in
inode->i_ino. Instead of basing it on BITS_PER_LONG, however, base it on
the size of the ino_t type.

NOTE: This is a user-visible change on 32-bit arches:

1/ inode numbers will be seen to have changed between kernel versions.
   32-bit arches will see large inode numbers now instead of the hashed
   ones they saw before.

2/ any really old software not built with LFS support may start failing
   stat() calls with -EOVERFLOW on inode numbers >2^32. Nothing much we
   can do about these, but hopefully the intersection of people running
   such code on ceph will be very small.

The workaround for both problems is to mount with "-o ino32".

[ idryomov: changelog tweak ]

URL: https://tracker.ceph.com/issues/46828
Reported-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Reported-and-Tested-by: Tuan Hoang1 <Tuan.Hoang1@ibm.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2020-08-24 17:25:26 +02:00
Bob Peterson 462582b99b gfs2: add some much needed cleanup for log flushes that fail
When a log flush fails due to io errors, it signals the failure but does
not clean up after itself very well. This is because buffers are added to
the transaction tr_buf and tr_databuf queue, but the io error causes
gfs2_log_flush to bypass the "after_commit" functions responsible for
dequeueing the bd elements. If the bd elements are added to the ail list
before the error, function ail_drain takes care of dequeueing them.
But if they haven't gotten that far, the elements are forgotten and
make the transactions unable to be freed.

This patch introduces new function trans_drain which drains the bd
elements from the transaction so they can be freed properly.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-08-24 13:54:07 +02:00
Max Filippov 2217b98262 binfmt_flat: revert "binfmt_flat: don't offset the data start"
binfmt_flat loader uses the gap between text and data to store data
segment pointers for the libraries. Even in the absence of shared
libraries it stores at least one pointer to the executable's own data
segment. Text and data can go back to back in the flat binary image and
without offsetting data segment last few instructions in the text
segment may get corrupted by the data segment pointer.

Fix it by reverting commit a2357223c5 ("binfmt_flat: don't offset the
data start").

Cc: stable@vger.kernel.org
Fixes: a2357223c5 ("binfmt_flat: don't offset the data start")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Greg Ungerer <gerg@linux-m68k.org>
2020-08-24 08:49:13 +10:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Pavel Begunkov 204361a77f io-wq: fix hang after cancelling pending hashed work
Don't forget to update wqe->hash_tail after cancelling a pending work
item, if it was hashed.

Cc: stable@vger.kernel.org # 5.7+
Reported-by: Dmitry Shulyak <yashulyak@gmail.com>
Fixes: 86f3cd1b58 ("io-wq: handle hashed writes in chains")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-23 11:38:50 -06:00
Jens Axboe fd7d6de224 io_uring: don't recurse on tsk->sighand->siglock with signalfd
If an application is doing reads on signalfd, and we arm the poll handler
because there's no data available, then the wakeup can recurse on the
tasks sighand->siglock as the signal delivery from task_work_add() will
use TWA_SIGNAL and that attempts to lock it again.

We can detect the signalfd case pretty easily by comparing the poll->head
wait_queue_head_t with the target task signalfd wait queue. Just use
normal task wakeup for this case.

Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-08-23 11:03:53 -06:00
Linus Torvalds f320ac6e13 Merge branch 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull epoll fixes from Al Viro:
 "Fix reference counting and clean up exit paths"

* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  do_epoll_ctl(): clean the failure exits up a bit
  epoll: Keep a reference on files added to the check list
2020-08-22 17:11:38 -07:00
Al Viro 52c479697c do_epoll_ctl(): clean the failure exits up a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-22 18:25:52 -04:00
Marc Zyngier a9ed4a6560 epoll: Keep a reference on files added to the check list
When adding a new fd to an epoll, and that this new fd is an
epoll fd itself, we recursively scan the fds attached to it
to detect cycles, and add non-epool files to a "check list"
that gets subsequently parsed.

However, this check list isn't completely safe when deletions
can happen concurrently. To sidestep the issue, make sure that
a struct file placed on the check list sees its f_count increased,
ensuring that a concurrent deletion won't result in the file
disapearing from under our feet.

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-22 18:23:57 -04:00