[ Upstream commit 67f4b5dc49 ]
Currently, when the writeback code detects a server reboot, it redirties
any pages that were not committed to disk, and it sets the flag
NFS_CONTEXT_RESEND_WRITES in the nfs_open_context of the file descriptor
that dirtied the file. While this allows the file descriptor in question
to redrive its own writes, it violates the fsync() requirement that we
should be synchronising all writes to disk.
While the problem is infrequent, we do see corner cases where an
untimely server reboot causes the fsync() call to abandon its attempt to
sync data to disk and causing data corruption issues due to missed error
conditions or similar.
In order to tighted up the client's ability to deal with this situation
without introducing livelocks, add a counter that records the number of
times pages are redirtied due to a server reboot-like condition, and use
that in fsync() to redrive the sync to disk.
Fixes: 2197e9b06c ("NFS: Fix up fsync() when the server rebooted")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e591b298d7 ]
Save some space in the nfs_inode by setting up an anonymous union with
the fields that are peculiar to a specific type of filesystem object.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit da48f267f9 ]
Assume that sections that should not re-enter the filesystem are already
protected with memalloc_nofs_save/restore call, so relax those GFP_NOFS
instances which might be used by other contexts.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d755ad8dc7 ]
For creating fattrs with the label field already allocated for us. I
also update nfs_free_fattr() to free the label in the end.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d4a95a7e5a ]
We're about to add a check in nfs_free_fattr() for whether or not the
label is non-zero.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit d19e0183a8 upstream.
The result of the writeback, whether it is an ENOSPC or an EIO, or
anything else, does not inhibit the NFS client from reporting the
correct file timestamps.
Fixes: 79566ef018 ("NFS: Getattr doesn't require data sync semantics")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit eea413308f ]
Both NFSv3 and NFSv2 generate their change attribute from the ctime
value that was supplied by the server. However the problem is that there
are plenty of servers out there with ctime resolutions of 1ms or worse.
In a modern performance system, this is insufficient when trying to
decide which is the most recent set of attributes when, for instance, a
READ or GETATTR call races with a WRITE or SETATTR.
For this reason, let's revert to labelling the NFSv2/v3 change
attributes as NFS4_CHANGE_TYPE_IS_UNDEFINED. This will ensure we protect
against such races.
Fixes: 7b24dacf08 ("NFS: Another inode revalidation improvement")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
If a file has already been closed, then it should not be selected to
support further I/O.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
[Trond: Fix an invalid pointer deref reported by Colin Ian King]
We know that the attributes changed on the server if and only if the
change attribute is different. Otherwise, we're just refreshing our
cache with values that were already known to be stale.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The inode is considered revalidated when we've checked the value of the
change attribute against our cached value since that suffices to
establish whether or not the other cached values are valid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Stable fixes:
- Add validation of the UDP retrans parameter to prevent shift out-of-bounds
- Don't discard pNFS layout segments that are marked for return
Bugfixes:
- Fix a NULL dereference crash in xprt_complete_bc_request() when the
NFSv4.1 server misbehaves.
- Fix the handling of NFS READDIR cookie verifiers
- Sundry fixes to ensure attribute revalidation works correctly when the
server does not return post-op attributes.
- nfs4_bitmask_adjust() must not change the server global bitmasks
- Fix major timeout handling in the RPC code.
- NFSv4.2 fallocate() fixes.
- Fix the NFSv4.2 SEEK_HOLE/SEEK_DATA end-of-file handling
- Copy offload attribute revalidation fixes
- Fix an incorrect filehandle size check in the pNFS flexfiles driver
- Fix several RDMA transport setup/teardown races
- Fix several RDMA queue wrapping issues
- Fix a misplaced memory read barrier in sunrpc's call_decode()
Features:
- Micro optimisation of the TCP transmission queue using TCP_CORK
- statx() performance improvements by further splitting up the tracking
of invalid cached file metadata.
- Support the NFSv4.2 "change_attr_type" attribute and use it to
optimise handling of change attribute updates.
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Merge tag 'nfs-for-5.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Add validation of the UDP retrans parameter to prevent shift
out-of-bounds
- Don't discard pNFS layout segments that are marked for return
Bugfixes:
- Fix a NULL dereference crash in xprt_complete_bc_request() when the
NFSv4.1 server misbehaves.
- Fix the handling of NFS READDIR cookie verifiers
- Sundry fixes to ensure attribute revalidation works correctly when
the server does not return post-op attributes.
- nfs4_bitmask_adjust() must not change the server global bitmasks
- Fix major timeout handling in the RPC code.
- NFSv4.2 fallocate() fixes.
- Fix the NFSv4.2 SEEK_HOLE/SEEK_DATA end-of-file handling
- Copy offload attribute revalidation fixes
- Fix an incorrect filehandle size check in the pNFS flexfiles driver
- Fix several RDMA transport setup/teardown races
- Fix several RDMA queue wrapping issues
- Fix a misplaced memory read barrier in sunrpc's call_decode()
Features:
- Micro optimisation of the TCP transmission queue using TCP_CORK
- statx() performance improvements by further splitting up the
tracking of invalid cached file metadata.
- Support the NFSv4.2 'change_attr_type' attribute and use it to
optimise handling of change attribute updates"
* tag 'nfs-for-5.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (85 commits)
xprtrdma: Fix a NULL dereference in frwr_unmap_sync()
sunrpc: Fix misplaced barrier in call_decode
NFSv4.2: Remove ifdef CONFIG_NFSD from NFSv4.2 client SSC code.
xprtrdma: Move fr_mr field to struct rpcrdma_mr
xprtrdma: Move the Work Request union to struct rpcrdma_mr
xprtrdma: Move fr_linv_done field to struct rpcrdma_mr
xprtrdma: Move cqe to struct rpcrdma_mr
xprtrdma: Move fr_cid to struct rpcrdma_mr
xprtrdma: Remove the RPC/RDMA QP event handler
xprtrdma: Don't display r_xprt memory addresses in tracepoints
xprtrdma: Add an rpcrdma_mr_completion_class
xprtrdma: Add tracepoints showing FastReg WRs and remote invalidation
xprtrdma: Avoid Send Queue wrapping
xprtrdma: Do not wake RPC consumer on a failed LocalInv
xprtrdma: Do not recycle MR after FastReg/LocalInv flushes
xprtrdma: Clarify use of barrier in frwr_wc_localinv_done()
xprtrdma: Rename frwr_release_mr()
xprtrdma: rpcrdma_mr_pop() already does list_del_init()
xprtrdma: Delete rpcrdma_recv_buffer_put()
xprtrdma: Fix cwnd update ordering
...
Pull vfs inode type handling updates from Al Viro:
"We should never change the type bits of ->i_mode or the method tables
(->i_op and ->i_fop) of a live inode.
Unfortunately, not all filesystems took care to prevent that"
* 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
spufs: fix bogosity in S_ISGID handling
9p: missing chunk of "fs/9p: Don't update file type when updating file attributes"
openpromfs: don't do unlock_new_inode() until the new inode is set up
hostfs_mknod(): don't bother with init_special_inode()
cifs: have cifs_fattr_to_inode() refuse to change type on live inode
cifs: have ->mkdir() handle race with another client sanely
do_cifs_create(): don't set ->i_mode of something we had not created
gfs2: be careful with inode refresh
ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode
orangefs_inode_is_stale(): i_mode type bits do *not* form a bitmap...
vboxsf: don't allow to change the inode type
afs: Fix updating of i_mode due to 3rd party change
ceph: don't allow type or device number to change on non-I_NEW inodes
ceph: fix up error handling with snapdirs
new helper: inode_wrong_type()
NFS_INO_REVAL_FORCED is intended to tell us that the cache needs
revalidation despite the fact that we hold a delegation. We shouldn't
need to store it anymore, though.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we're trying to update the inode because a previous update left the
cache in a partially unrevalidated state, then allow the update if the
change attrs match.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the NFSv4.2 server supports the 'change_attr_type' attribute, then
allow the client to optimise its attribute cache update strategy.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We should not be invalidating the access or acl caches in
nfs_check_inode_attributes(), since the point is we're unsure about
whether the contents of the struct nfs_fattr are fully up to date.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Commit 0b467264d0 ("NFS: Fix attribute revalidation") changed the way
we populate the 'invalid' attribute, and made the line that strips away
the NFS_INO_INVALID_ATTR bits redundant.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If there is an outstanding layoutcommit, then the list of attributes
whose values are expected to change is not the full set. So let's
be explicit about the full list.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
chown()/chgrp() and chmod() are separate operations, and in addition,
there are mode operations that are performed automatically by the
server. So let's track mode validity separately from the file ownership
validity.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Rename can cause us to revalidate the access cache, so lets track the
nlinks separately from the mode/uid/gid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When checking cache validity, be more specific than just 'we want to
check the page cache validity'. In almost all cases, we want to check
that change attribute, and possibly also the size.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add an argument to nfs_revalidate_inode() to allow callers to specify
which attributes they need to check for validity.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we do a 'chown' or 'chgrp', the server will clear the suid/sgid
bits. Ensure that we mirror that in nfs_setattr_update_inode().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If statx has valid attributes available that weren't asked for, then
return them and set the result mask appropriately.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the user doesn't set STATX_UID/GID/MODE, then don't care if they are
known to be stale. Ditto if we're not being asked for the file size.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that when the change attribute or the size change, we also
remember to revalidate the space used.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we're looking to revalidate the page cache, we should just ensure
that we mark the change attribute invalid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We don't currently support STATX_BTIME, so don't advertise it in the
return values for nfs_getattr().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We need to use unsigned long subtraction and then convert to signed in
order to deal correcly with C overflow rules.
Fixes: f506200346 ("NFS: Set an attribute barrier on all updates")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
nfs_set_cache_invalid() has code to handle delegations, and other
optimisations, so let's use it when appropriate.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
inode_wrong_type(inode, mode) returns true if setting inode->i_mode
to given value would've changed the inode type. We have enough of
those checks open-coded to make a helper worthwhile.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
- New Features:
- Support for eager writes, and the write=eager and write=wait mount options
- Other Bugfixes and Cleanups:
- Fix typos in some comments
- Fix up fall-through warnings for Clang
- Cleanups to the NFS readpage codepath
- Remove FMR support in rpcrdma_convert_iovs()
- Various other cleanups to xprtrdma
- Fix xprtrdma pad optimization for servers that don't support RFC 8797
- Improvements to rpcrdma tracepoints
- Fix up nfs4_bitmask_adjust()
- Optimize sparse writes past the end of files
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Merge tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS Client Updates from Anna Schumaker:
"New Features:
- Support for eager writes, and the write=eager and write=wait mount
options
- Other Bugfixes and Cleanups:
- Fix typos in some comments
- Fix up fall-through warnings for Clang
- Cleanups to the NFS readpage codepath
- Remove FMR support in rpcrdma_convert_iovs()
- Various other cleanups to xprtrdma
- Fix xprtrdma pad optimization for servers that don't support
RFC 8797
- Improvements to rpcrdma tracepoints
- Fix up nfs4_bitmask_adjust()
- Optimize sparse writes past the end of files"
* tag 'nfs-for-5.12-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (27 commits)
NFS: Support the '-owrite=' option in /proc/self/mounts and mountinfo
NFS: Set the stable writes flag when initialising the super block
NFS: Add mount options supporting eager writes
NFS: Add support for eager writes
NFS: 'flags' field should be unsigned in struct nfs_server
NFS: Don't set NFS_INO_INVALID_XATTR if there is no xattr cache
NFS: Always clear an invalid mapping when attempting a buffered write
NFS: Optimise sparse writes past the end of file
NFS: Fix documenting comment for nfs_revalidate_file_size()
NFSv4: Fixes for nfs4_bitmask_adjust()
xprtrdma: Clean up rpcrdma_prepare_readch()
rpcrdma: Capture bytes received in Receive completion tracepoints
xprtrdma: Pad optimization, revisited
rpcrdma: Fix comments about reverse-direction operation
xprtrdma: Refactor invocations of offset_in_page()
xprtrdma: Simplify rpcrdma_convert_kvec() and frwr_map()
xprtrdma: Remove FMR support in rpcrdma_convert_iovs()
NFS: Add nfs_pageio_complete_read() and remove nfs_readpage_async()
NFS: Call readpage_async_filler() from nfs_readpage_async()
NFS: Refactor nfs_readpage() and nfs_readpage_async() to use nfs_readdesc
...
If the page cache is invalid, then we can't do read-modify-write, so
ensure that we do clear it when we know it is invalid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
nfsiod is currently a concurrency-managed workqueue (CMWQ).
This means that workitems scheduled to nfsiod on a given CPU are queued
behind all other work items queued on any CMWQ on the same CPU. This
can introduce unexpected latency.
Occaionally nfsiod can even cause excessive latency. If the work item
to complete a CLOSE request calls the final iput() on an inode, the
address_space of that inode will be dismantled. This takes time
proportional to the number of in-memory pages, which on a large host
working on large files (e.g.. 5TB), can be a large number of pages
resulting in a noticable number of seconds.
We can avoid these latency problems by switching nfsiod to WQ_UNBOUND.
This causes each concurrent work item to gets a dedicated thread which
can be scheduled to an idle CPU.
There is precedent for this as several other filesystems use WQ_UNBOUND
workqueue for handling various async events.
Signed-off-by: NeilBrown <neilb@suse.de>
Fixes: ada609ee2a ("workqueue: use WQ_MEM_RECLAIM instead of WQ_RESCUER")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the server insists on using the readdir verifiers in order to allow
cookies to expire, then we should ensure that we cache the verifier
with the cookie, so that we can return an error if the application
tries to use the expired cookie.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Implement client side caching for NFSv4.2 extended attributes. The cache
is a per-inode hashtable, with name/value entries. There is one special
entry for the listxattr cache.
NFS inodes have a pointer to a cache structure. The cache structure is
allocated on demand, freed when the cache is invalidated.
Memory shrinkers keep the size in check. Large entries (> PAGE_SIZE)
are collected by a separate shrinker, and freed more aggressively
than others.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Define the NFS_INO_INVALID_XATTR flag, to be used for the NFSv4.2 xattr
cache, and use it where appropriate.
No functional change as yet.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the application uses the AT_STATX_DONT_SYNC flag after doing readdir(),
then we should still mark the parent inode as seeing a readdirplus hit.
That ensures that we continue to use readdirplus in the 'ls -l' type
of workflow to do fast lookups of the dentries.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Trond Myklebust
Anna Schumaker
ChenXiaoSong
Linus Torvalds
Trond Myklebust
Al Viro
Christian Brauner
NeilBrown
Frank van der Linden