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>
- 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>
Use the following command to test nfsv4(size of file1M is 1MB):
mount -t nfs -o vers=4.0,actimeo=60 127.0.0.1/dir1 /mnt
cp file1M /mnt
du -h /mnt/file1M -->0 within 60s, then 1M
When write is done(cp file1M /mnt), will call this:
nfs_writeback_done
nfs4_write_done
nfs4_write_done_cb
nfs_writeback_update_inode
nfs_post_op_update_inode_force_wcc_locked(change, ctime, mtime
nfs_post_op_update_inode_force_wcc_locked
nfs_set_cache_invalid
nfs_refresh_inode_locked
nfs_update_inode
nfsd write response contains change, ctime, mtime, the flag will be
clear after nfs_update_inode. Howerver, write response does not contain
space_used, previous open response contains space_used whose value is 0,
so inode->i_blocks is still 0.
nfs_getattr -->called by "du -h"
do_update |= force_sync || nfs_attribute_cache_expired -->false in 60s
cache_validity = READ_ONCE(NFS_I(inode)->cache_validity)
do_update |= cache_validity & (NFS_INO_INVALID_ATTR -->false
if (do_update) {
__nfs_revalidate_inode
}
Within 60s, does not send getattr request to nfsd, thus "du -h /mnt/file1M"
is 0.
Add a NFS_INO_INVALID_BLOCKS flag, set it when nfsv4 write is done.
Fixes: 16e1437517 ("NFS: More fine grained attribute tracking")
Signed-off-by: Zheng Bin <zhengbin13@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Instead of the various open coded calls to set the NFS_INO_STALE bit
and call nfs_zap_caches(), consolidate them into a single function
nfs_set_inode_stale().
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>
If a dentry was not initially looked up while we were holding a
delegation, then we do still need to revalidate that it still holds
the same name. If there are multiple hard links to the same file,
then all the hard links need validation.
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
[Anna: Put nfs_unset_verifier_delegated() under CONFIG_NFS_V4]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We want to find open contexts that match our filesystem access
properties. They don't have to exactly match the cred.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add a mount option 'softreval' that allows attribute revalidation 'getattr'
calls to time out, and causes them to fall back to using the cached
attributes.
The use case for this option is for ensuring that we can still (slowly)
traverse paths and use cached information even when the server is down.
Once the server comes back up again, the getattr calls start succeeding,
and the caches will revalidate as usual.
The 'softreval' mount option is automatically enabled if you have
specified 'softerr'. It can be turned off using the options
'nosoftreval', or 'hard'.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFSv4 supports 64-bit times, so we should switch to using struct
timespec64 when decoding attributes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We want to throw out the attrbute if it refers to the mounted on fileid,
and not the real fileid. However we do not want to block cache consistency
updates from NFSv4 writes.
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Fixes: 7e10cc25bf ("NFS: Don't refresh attributes with mounted-on-file...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we've been given the attributes of the mounted-on-file, then do not
use those to check or update the attributes on the application-visible
inode.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the client detects that close-to-open cache consistency has been
violated, and that the file or directory has been changed on the
server, then do a cache invalidation when we're done working with
the file.
The reason we don't do an immediate cache invalidation is that we
want to avoid performance problems due to false positives. Also,
note that we cannot guarantee cache consistency in this situation
even if we do invalidate the cache.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
According to the open() manpage, Linux reserves the access mode 3
to mean "check for read and write permission on the file and return
a file descriptor that can't be used for reading or writing."
Currently, the NFSv4 code will ask the server to open the file,
and will use an incorrect share access mode of 0. Since it has
an incorrect share access mode, the client later forgets to send
a corresponding close, meaning it can leak stateids on the server.
Fixes: ce4ef7c0a8 ("NFS: Split out NFS v4 file operations")
Cc: stable@vger.kernel.org # 3.6+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Stable bugfixes:
- Fall back to MDS if no deviceid is found rather than aborting # v4.11+
- NFS4: Fix v4.0 client state corruption when mount
Features:
- Much improved handling of soft mounts with NFS v4.0
- Reduce risk of false positive timeouts
- Faster failover of reads and writes after a timeout
- Added a "softerr" mount option to return ETIMEDOUT instead of
EIO to the application after a timeout
- Increase number of xprtrdma backchannel requests
- Add additional xprtrdma tracepoints
- Improved send completion batching for xprtrdma
Other bugfixes and cleanups:
- Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
- Reduce usage of GFP_ATOMIC pages in SUNRPC
- Various minor NFS over RDMA cleanups and bugfixes
- Use the correct container namespace for upcalls
- Don't share superblocks between user namespaces
- Various other container fixes
- Make nfs_match_client() killable to prevent soft lockups
- Don't mark all open state for recovery when handling recallable state revoked flag
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Merge tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Highlights include:
Stable bugfixes:
- Fall back to MDS if no deviceid is found rather than aborting # v4.11+
- NFS4: Fix v4.0 client state corruption when mount
Features:
- Much improved handling of soft mounts with NFS v4.0:
- Reduce risk of false positive timeouts
- Faster failover of reads and writes after a timeout
- Added a "softerr" mount option to return ETIMEDOUT instead of
EIO to the application after a timeout
- Increase number of xprtrdma backchannel requests
- Add additional xprtrdma tracepoints
- Improved send completion batching for xprtrdma
Other bugfixes and cleanups:
- Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
- Reduce usage of GFP_ATOMIC pages in SUNRPC
- Various minor NFS over RDMA cleanups and bugfixes
- Use the correct container namespace for upcalls
- Don't share superblocks between user namespaces
- Various other container fixes
- Make nfs_match_client() killable to prevent soft lockups
- Don't mark all open state for recovery when handling recallable
state revoked flag"
* tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (69 commits)
SUNRPC: Rebalance a kref in auth_gss.c
NFS: Fix a double unlock from nfs_match,get_client
nfs: pass the correct prototype to read_cache_page
NFSv4: don't mark all open state for recovery when handling recallable state revoked flag
SUNRPC: Fix an error code in gss_alloc_msg()
SUNRPC: task should be exit if encode return EKEYEXPIRED more times
NFS4: Fix v4.0 client state corruption when mount
PNFS fallback to MDS if no deviceid found
NFS: make nfs_match_client killable
lockd: Store the lockd client credential in struct nlm_host
NFS: When mounting, don't share filesystems between different user namespaces
NFS: Convert NFSv2 to use the container user namespace
NFSv4: Convert the NFS client idmapper to use the container user namespace
NFS: Convert NFSv3 to use the container user namespace
SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall
SUNRPC: Use the client user namespace when encoding creds
NFS: Store the credential of the mount process in the nfs_server
SUNRPC: Cache cred of process creating the rpc_client
xprtrdma: Remove stale comment
xprtrdma: Update comments that reference ib_drain_qp
...
Force the lock context to keep a reference to the parent open
context so that we can guarantee the validity of the latter.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fix up some compiler warnings about function parameters, etc not being
correctly described or formatted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
SUNRPC has two sorts of credentials, both of which appear as
"struct rpc_cred".
There are "generic credentials" which are supplied by clients
such as NFS and passed in 'struct rpc_message' to indicate
which user should be used to authorize the request, and there
are low-level credentials such as AUTH_NULL, AUTH_UNIX, AUTH_GSS
which describe the credential to be sent over the wires.
This patch replaces all the generic credentials by 'struct cred'
pointers - the credential structure used throughout Linux.
For machine credentials, there is a special 'struct cred *' pointer
which is statically allocated and recognized where needed as
having a special meaning. A look-up of a low-level cred will
map this to a machine credential.
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFS needs to know when a credential is about to expire so that
it can modify write-back behaviour to finish the write inside the
expiry time.
It currently uses functions in SUNRPC code which make use of a
fairly complex callback scheme and flags in the generic credientials.
As I am working to discard the generic credentials, this has to change.
This patch moves the logic into NFS, in part by finding and caching
the low-level credential in the open_context. We then make direct
cred-api calls on that.
This makes the code much simpler and removes a dependency on generic
rpc credentials.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Reduce contention on the inode->i_lock by ensuring that we use RCU
when looking up the NFS open context.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Speed up lookups of an existing lock context by avoiding the inode->i_lock,
and using RCU instead.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
