Instead of trying to save the commit verifiers and checking them against
previous writes, adopt the same strategy as for buffered writes, of
just checking the verifiers at commit time.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add a pNFS callback to allow the O_DIRECT code to release the DS
commitinfo when freeing the dreq.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_commit_pagelist().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_recover_commit_reqs().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add support for scanning the full list of per-layout segment commit
arrays to pnfs_generic_scan_commit_lists()
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we have multiple layout segments with different lists of mirrored
data, we need to track the commits on a per layout segment basis.
This patch adds a list to support this tracking in struct
pnfs_ds_commit_info.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Refactor pnfs_generic_commit_pagelist() to simplify the conversion
to layout segment based commit lists.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Just allocate the array at the end of the layout segment structure,
instead of allocating it as a separate array of pointers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
UDP was originally disabled in 6da1a03436 for NFSv4. Later in
b24ee6c64c UDP is by default disabled by NFS_DISABLE_UDP_SUPPORT=y for
all NFS versions. Therefore remove v4 from error message.
Fixes: b24ee6c64c ("NFS: allow deprecation of NFS UDP protocol")
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
UDP is disabled by default in commit b24ee6c64c ("NFS: allow
deprecation of NFS UDP protocol"), but the default mount options
is still udp, change it to tcp to avoid the "Unsupported transport
protocol udp" error if no protocol is specified when mount nfs.
Fixes: b24ee6c64c ("NFS: allow deprecation of NFS UDP protocol")
Signed-off-by: Liwei Song <liwei.song@windriver.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When dreq is allocated by nfs_direct_req_alloc(), dreq->kref is
initialized to 2. Therefore we need to call nfs_direct_req_release()
twice to release the allocated dreq. Usually it is called in
nfs_file_direct_{read, write}() and nfs_direct_complete().
However, current code only calls nfs_direct_req_relese() once if
nfs_get_lock_context() fails in nfs_file_direct_{read, write}().
So, that case would result in memory leak.
Fix this by adding the missing call.
Signed-off-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In function nfs_permission:
1. the rcu_read_lock and rcu_read_unlock around nfs_do_access
is unnecessary because the rcu critical data structure is already
protected in subsidiary function nfs_access_get_cached_rcu. No other
data structure needs rcu_read_lock in nfs_do_access.
2. call nfs_do_access once is enough, because:
2-1. when mask has MAY_NOT_BLOCK bit
The second call to nfs_do_access will not happen.
2-2. when mask has no MAY_NOT_BLOCK bit
The second call to nfs_do_access will happen if res == -ECHILD, which
means the first nfs_do_access goes out after statement if (!may_block).
The second call to nfs_do_access will go through this procedure once
again except continue the work after if (!may_block).
But above work can be performed by only one call to nfs_do_access
without mangling the mask flag.
Tested in x86_64
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we receive a CB_RECALL_ANY that asks us to return flexfiles
layouts, we iterate through all the layouts and look at whether or
not there are active open file descriptors that might need them
for I/O. If there are no such descriptors, we return the layouts.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert nfs_delegation_reap_unclaimed() to use nfs_client_for_each_server()
for efficiency.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert it to use the nfs_client_for_each_server() helper, and
make it more efficient by skipping delegations for inodes we
know are in the process of being freed. Also improve the efficiency
of the cursor by skipping delegations that are being freed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add a helper nfs_client_for_each_server() to iterate through all the
filesystems that are attached to a struct nfs_client, and apply
a function to all the active ones.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Now that we can rely on just the rcu_read_lock(), remove the
clp->cl_lock and clean up.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Make sure to test the stateid for validity so that we catch instances
where the server may have been reusing stateids in
nfs_layout_find_inode_by_stateid().
Fixes: 7b410d9ce4 ("pNFS: Delay getting the layout header in CB_LAYOUTRECALL handlers")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that if the DS is returning too many DELAY and GRACE errors, we
also report that to the MDS through the layouterror mechanism.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Currently, we have no real limit on the access cache size (we set it
to ULONG_MAX). That can lead to credentials getting pinned for a
very long time on lots of files if you have a system with a lot of
memory.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In both async rename and rename, we take a reference to the
cred in the call arguments.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Avoid unnecessary references to the cred when we have already referenced
it through the open context or the open owner.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In read/write/commit, we should be able to assume that the cred is
pinned by the open context.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we're creating a nfs_open_context() for a specific file pointer,
we must use the cred assigned to that file.
Fixes: a52458b48a ("NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We can't allow delegreturn to hold up nfs4_evict_inode() forever,
since that can cause the memory shrinkers to block. This patch
therefore ensures that we eventually time out, and complete the
reclaim of the inode.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the cred assigned to the layout that we're updating differs from
the one used to retrieve the new layout segment, then we need to
update the layout plh_lc_cred field.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the cred assigned to the delegation that we're updating differs
from the one we're updating too, then we need to update that field
too.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we're running as a 64-bit architecture and are not running in
32-bit compatibility mode, it is better to use the 64-bit readdir
cookies that supplied by the server. Doing so improves the accuracy
of telldir()/seekdir(), particularly when the directory is changing,
for instance, when doing 'rm -rf'.
We still fall back to using the 32-bit offsets on 32-bit architectures
and when in compatibility mode.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
prevent inodes from vanishing, but ihold() does not guarantee inode
persistence. Replace the inode pointer with a per boot, machine wide,
unique inode identifier. The second commit fixes the breakage of the hash
mechanism whihc causes a 100% performance regression.
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Merge tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex fix from Thomas Gleixner:
"Fix for yet another subtle futex issue.
The futex code used ihold() to prevent inodes from vanishing, but
ihold() does not guarantee inode persistence. Replace the inode
pointer with a per boot, machine wide, unique inode identifier.
The second commit fixes the breakage of the hash mechanism which
causes a 100% performance regression"
* tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Unbreak futex hashing
futex: Fix inode life-time issue
Fixes:
- Ensure the fs_context has the correct fs_type when mounting and submounting
- Fix leaking of ctx->nfs_server.hostname
- Add minor version to fscache key to prevent collisions
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Merge tag 'nfs-for-5.6-3' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client bugfixes from Anna Schumaker:
"These are mostly fscontext fixes, but there is also one that fixes
collisions seen in fscache:
- Ensure the fs_context has the correct fs_type when mounting and
submounting
- Fix leaking of ctx->nfs_server.hostname
- Add minor version to fscache key to prevent collisions"
* tag 'nfs-for-5.6-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
nfs: add minor version to nfs_server_key for fscache
NFS: Fix leak of ctx->nfs_server.hostname
NFS: Don't hard-code the fs_type when submounting
NFS: Ensure the fs_context has the correct fs_type before mounting
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Merge tag 'fuse-fixes-5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fix from Miklos Szeredi:
"Fix an Oops introduced in v5.4"
* tag 'fuse-fixes-5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: fix stack use after return
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Merge tag 'ovl-fixes-5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
"Fix three bugs introduced in this cycle"
* tag 'ovl-fixes-5.6-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: fix lockdep warning for async write
ovl: fix some xino configurations
ovl: fix lock in ovl_llseek()
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Merge tag 'io_uring-5.6-2020-03-13' of git://git.kernel.dk/linux-block
Pull io_uring fix from Jens Axboe:
"Just a single fix here, improving the RCU callback ordering from last
week. After a bit more perusing by Paul, he poked a hole in the
original"
* tag 'io_uring-5.6-2020-03-13' of git://git.kernel.dk/linux-block:
io_uring: ensure RCU callback ordering with rcu_barrier()
afs_put_addrlist() casts kfree() to rcu_callback_t. Apart from being wrong
in theory, this might also blow up when people start enforcing function
types via compiler instrumentation, and it means the rcu_head has to be
first in struct afs_addr_list.
Use kfree_rcu() instead, it's simpler and more correct.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lockdep reports "WARNING: lock held when returning to user space!" due to
async write holding freeze lock over the write. Apparently aio.c already
deals with this by lying to lockdep about the state of the lock.
Do the same here. No need to check for S_IFREG() here since these file ops
are regular-only.
Reported-by: syzbot+9331a354f4f624a52a55@syzkaller.appspotmail.com
Fixes: 2406a307ac ("ovl: implement async IO routines")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fix up two bugs in the coversion to xino_mode:
1. xino=off does not always end up in disabled mode
2. xino=auto on 32bit arch should end up in disabled mode
Take a proactive approach to disabling xino on 32bit kernel:
1. Disable XINO_AUTO config during build time
2. Disable xino with a warning on mount time
As a by product, xino=on on 32bit arch also ends up in disabled mode.
We never intended to enable xino on 32bit arch and this will make the
rest of the logic simpler.
Fixes: 0f831ec85e ("ovl: simplify ovl_same_sb() helper")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Pull vfs fixes from Al Viro:
"A couple of fixes for old crap in ->atomic_open() instances"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
cifs_atomic_open(): fix double-put on late allocation failure
gfs2_atomic_open(): fix O_EXCL|O_CREAT handling on cold dcache
several iterations of ->atomic_open() calling conventions ago, we
used to need fput() if ->atomic_open() failed at some point after
successful finish_open(). Now (since 2016) it's not needed -
struct file carries enough state to make fput() work regardless
of the point in struct file lifecycle and discarding it on
failure exits in open() got unified. Unfortunately, I'd missed
the fact that we had an instance of ->atomic_open() (cifs one)
that used to need that fput(), as well as the stale comment in
finish_open() demanding such late failure handling. Trivially
fixed...
Fixes: fe9ec8291f "do_last(): take fput() on error after opening to out:"
Cc: stable@kernel.org # v4.7+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
with the way fs/namei.c:do_last() had been done, ->atomic_open()
instances needed to recognize the case when existing file got
found with O_EXCL|O_CREAT, either by falling back to finish_no_open()
or failing themselves. gfs2 one didn't.
Fixes: 6d4ade986f (GFS2: Add atomic_open support)
Cc: stable@kernel.org # v3.11
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ovl_inode_lock() is interruptible. When inode_lock() in ovl_llseek()
was replaced with ovl_inode_lock(), we did not add a check for error.
Fix this by making ovl_inode_lock() uninterruptible and change the
existing call sites to use an _interruptible variant.
Reported-by: syzbot+66a9752fa927f745385e@syzkaller.appspotmail.com
Fixes: b1f9d3858f ("ovl: use ovl_inode_lock in ovl_llseek()")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fix a bug where if userspace is writing to encrypted files while the
FS_IOC_REMOVE_ENCRYPTION_KEY ioctl (introduced in v5.4) is running,
dirty inodes could be evicted, causing writes could be lost or the
filesystem to hang due to a use-after-free. This was encountered during
real-world use, not just theoretical.
Tested with the existing fscrypt xfstests, and with a new xfstest I
wrote to reproduce this bug. This fix does expose an existing bug with
'-o lazytime' that Ted is working on fixing, but this fix is more
critical and needed anyway regardless of the lazytime fix.
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Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
Pull fscrypt fix from Eric Biggers:
"Fix a bug where if userspace is writing to encrypted files while the
FS_IOC_REMOVE_ENCRYPTION_KEY ioctl (introduced in v5.4) is running,
dirty inodes could be evicted, causing writes could be lost or the
filesystem to hang due to a use-after-free. This was encountered
during real-world use, not just theoretical.
Tested with the existing fscrypt xfstests, and with a new xfstest I
wrote to reproduce this bug. This fix does expose an existing bug with
'-o lazytime' that Ted is working on fixing, but this fix is more
critical and needed anyway regardless of the lazytime fix"
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
fscrypt: don't evict dirty inodes after removing key
After more careful studying, Paul informs me that we cannot rely on
ordering of RCU callbacks in the way that the the tagged commit did.
The current construct looks like this:
void C(struct rcu_head *rhp)
{
do_something(rhp);
call_rcu(&p->rh, B);
}
call_rcu(&p->rh, A);
call_rcu(&p->rh, C);
and we're relying on ordering between A and B, which isn't guaranteed.
Make this explicit instead, and have a work item issue the rcu_barrier()
to ensure that A has run before we manually execute B.
While thorough testing never showed this issue, it's dependent on the
per-cpu load in terms of RCU callbacks. The updated method simplifies
the code as well, and eliminates the need to maintain an rcu_head in
the fileset data.
Fixes: c1e2148f8e ("io_uring: free fixed_file_data after RCU grace period")
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Trond Myklebust