Change the nfs filesystem to support fscache's indexing rewrite and
reenable caching in nfs.
The following changes have been made:
(1) The fscache_netfs struct is no more, and there's no need to register
the filesystem as a whole.
(2) The session cookie is now an fscache_volume cookie, allocated with
fscache_acquire_volume(). That takes three parameters: a string
representing the "volume" in the index, a string naming the cache to
use (or NULL) and a u64 that conveys coherency metadata for the
volume.
For nfs, I've made it render the volume name string as:
"nfs,<ver>,<family>,<address>,<port>,<fsidH>,<fsidL>*<,param>[,<uniq>]"
(3) The fscache_cookie_def is no more and needed information is passed
directly to fscache_acquire_cookie(). The cache no longer calls back
into the filesystem, but rather metadata changes are indicated at
other times.
fscache_acquire_cookie() is passed the same keying and coherency
information as before.
(4) fscache_enable/disable_cookie() have been removed.
Call fscache_use_cookie() and fscache_unuse_cookie() when a file is
opened or closed to prevent a cache file from being culled and to keep
resources to hand that are needed to do I/O.
If a file is opened for writing, we invalidate it with
FSCACHE_INVAL_DIO_WRITE in lieu of doing writeback to the cache,
thereby making it cease caching until all currently open files are
closed. This should give the same behaviour as the uptream code.
Making the cache store local modifications isn't straightforward for
NFS, so that's left for future patches.
(5) fscache_invalidate() now needs to be given uptodate auxiliary data and
a file size. It also takes a flag to indicate if this was due to a
DIO write.
(6) Call nfs_fscache_invalidate() with FSCACHE_INVAL_DIO_WRITE on a file
to which a DIO write is made.
(7) Call fscache_note_page_release() from nfs_release_page().
(8) Use a killable wait in nfs_vm_page_mkwrite() when waiting for
PG_fscache to be cleared.
(9) The functions to read and write data to/from the cache are stubbed out
pending a conversion to use netfslib.
Changes
=======
ver #3:
- Added missing =n fallback for nfs_fscache_release_file()[1][2].
ver #2:
- Use gfpflags_allow_blocking() rather than using flag directly.
- fscache_acquire_volume() now returns errors.
- Remove NFS_INO_FSCACHE as it's no longer used.
- Need to unuse a cookie on file-release, not inode-clear.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Co-developed-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: Anna Schumaker <anna.schumaker@netapp.com>
cc: linux-nfs@vger.kernel.org
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/202112100804.nksO8K4u-lkp@intel.com/ [1]
Link: https://lore.kernel.org/r/202112100957.2oEDT20W-lkp@intel.com/ [2]
Link: https://lore.kernel.org/r/163819668938.215744.14448852181937731615.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906979003.143852.2601189243864854724.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967182112.1823006.7791504655391213379.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021575950.640689.12069642327533368467.stgit@warthog.procyon.org.uk/ # v4
This provides some insight into the client's invalidation behavior to show
both when the client uses the helper, and the results of calling the
helper which can vary depending on how the helper is called.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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>
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>
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>
Generate a trace event whenever the NFS client modifies the size of
a file. These new events aid troubleshooting workloads that trigger
races around size updates.
There are four new trace points, all named nfs_size_something so
they are easy to grep for or enable as a group with a single glob.
Size updated on the server:
kworker/u24:10-194 [010] 369.939174: nfs_size_update: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899344277980615 cursize=250471 newsize=172083
Server-side size update reported via NFSv3 WCC attributes:
fsx-1387 [006] 380.760686: nfs_size_wcc: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899355909932456 cursize=146792 newsize=171216
File has been truncated locally:
fsx-1387 [007] 369.437421: nfs_size_truncate: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899231200117272 cursize=215244 newsize=0
File has been extended locally:
fsx-1387 [007] 369.439213: nfs_size_grow: fileid=00:28:2 fhandle=0x36fbbe51 version=1752899343704248410 cursize=258048 newsize=262144
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
NFS_INO_DATA_INVAL_DEFER and NFS_INO_INVALID_DATA should be considered
mutually exclusive.
Fixes: 1c341b7775 ("NFS: Add deferred cache invalidation for close-to-open consistency violations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
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>
If the cached credential exists but doesn't have any expiration callback
then exit early.
Fix up atomicity issues when replacing the credential with a new one
since the existing code could lead to refcount leaks.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
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.
-----BEGIN PGP SIGNATURE-----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=h01b
-----END PGP SIGNATURE-----
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
-----BEGIN PGP SIGNATURE-----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=Dssn
-----END PGP SIGNATURE-----
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>
Dave Wysochanski
Benjamin Coddington
Anna Schumaker
Trond Myklebust
Chuck Lever
Linus Torvalds
Trond Myklebust
Al Viro
Christian Brauner