We have never been able to track down and address the underlying
cause of the performance issues with workqueue-based service
support. svo_enqueue_xprt is called multiple times per RPC, so
it adds instruction path length, but always ends up at the same
function: svc_xprt_do_enqueue(). We do not anticipate needing
this flexibility for dynamic nfsd thread management support.
As a micro-optimization, remove .svo_enqueue_xprt because
Spectre/Meltdown makes virtual function calls more costly.
This change essentially reverts commit b9e13cdfac ("nfsd/sunrpc:
turn enqueueing a svc_xprt into a svc_serv operation").
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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>
Commit ac795161c9 (NFSv4: Handle case where the lookup of a directory
fails) [1], part of Linux since 5.17-rc2, introduced a regression, where
a symbolic link on an NFS mount to a directory on another NFS does not
resolve(?) the first time it is accessed:
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Fixes: ac795161c9 ("NFSv4: Handle case where the lookup of a directory fails")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Donald Buczek <buczek@molgen.mpg.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In nfs4_update_changeattr_locked(), we don't need to set the
NFS_INO_REVAL_PAGECACHE flag, because we already know the value of the
change attribute, and we're already flagging the size. In fact, this
forces us to revalidate the change attribute a second time for no good
reason.
This extra flag appears to have been introduced as part of the xattr
feature, when update_changeattr_locked() was converted for use by the
xattr code.
Fixes: 1b523ca972 ("nfs: modify update_changeattr to deal with regular files")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add the description of @server and @fhandle, and remove the excess
@inode in nfs4_proc_get_locations() kernel-doc comment to remove
warnings found by running scripts/kernel-doc, which is caused by
using 'make W=1'.
fs/nfs/nfs4proc.c:8219: warning: Function parameter or member 'server'
not described in 'nfs4_proc_get_locations'
fs/nfs/nfs4proc.c:8219: warning: Function parameter or member 'fhandle'
not described in 'nfs4_proc_get_locations'
fs/nfs/nfs4proc.c:8219: warning: Excess function parameter 'inode'
description in 'nfs4_proc_get_locations'
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For some long forgotten reason, the nfs_client cl_flags field is
initialised in nfs_get_client() instead of being initialised at
allocation time. This quirk was harmless until we moved the call to
nfs_create_rpc_client().
Fixes: dd99e9f98f ("NFSv4: Initialise connection to the server in nfs4_alloc_client()")
Cc: stable@vger.kernel.org # 4.8.x
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we've reached the end of the directory, then cache that information
in the context so that we don't need to do an uncached readdir in order
to rediscover that fact.
Fixes: 794092c57f ("NFS: Do uncached readdir when we're seeking a cookie in an empty page cache")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we're doing an uncached read of the directory, then we ideally want
to read only the exact set of entries that will fit in the buffer
supplied by the getdents() system call. So unlike the case where we're
reading into the page cache, let's send only one READDIR call, before
trying to fill up the buffer.
Fixes: 35df59d3ef ("NFS: Reduce number of RPC calls when doing uncached readdir")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
- New Features:
- Basic handling for case insensitive filesystems
- Initial support for fs_locations and server trunking
- Bugfixes and Cleanups:
- Cleanups to how the "struct cred *" is handled for the nfs_access_entry
- Ensure the server has an up to date ctimes before hardlinking or renaming
- Update 'blocks used' after writeback, fallocate, and clone
- nfs_atomic_open() fixes
- Improvements to sunrpc tracing
- Various null check & indenting related cleanups
- Some improvements to the sunrpc sysfs code
- Use default_groups in kobj_type
- Fix some potential races and reference leaks
- A few tracepoint cleanups in xprtrdma
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Merge tag 'nfs-for-5.17-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"New Features:
- Basic handling for case insensitive filesystems
- Initial support for fs_locations and server trunking
Bugfixes and Cleanups:
- Cleanups to how the "struct cred *" is handled for the
nfs_access_entry
- Ensure the server has an up to date ctimes before hardlinking or
renaming
- Update 'blocks used' after writeback, fallocate, and clone
- nfs_atomic_open() fixes
- Improvements to sunrpc tracing
- Various null check & indenting related cleanups
- Some improvements to the sunrpc sysfs code:
- Use default_groups in kobj_type
- Fix some potential races and reference leaks
- A few tracepoint cleanups in xprtrdma"
[ This should have gone in during the merge window, but didn't. The
original pull request - sent during the merge window - had gotten
marked as spam and discarded due missing DKIM headers in the email
from Anna. - Linus ]
* tag 'nfs-for-5.17-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (35 commits)
SUNRPC: Don't dereference xprt->snd_task if it's a cookie
xprtrdma: Remove definitions of RPCDBG_FACILITY
xprtrdma: Remove final dprintk call sites from xprtrdma
sunrpc: Fix potential race conditions in rpc_sysfs_xprt_state_change()
net/sunrpc: fix reference count leaks in rpc_sysfs_xprt_state_change
NFSv4.1 test and add 4.1 trunking transport
SUNRPC allow for unspecified transport time in rpc_clnt_add_xprt
NFSv4 handle port presence in fs_location server string
NFSv4 expose nfs_parse_server_name function
NFSv4.1 query for fs_location attr on a new file system
NFSv4 store server support for fs_location attribute
NFSv4 remove zero number of fs_locations entries error check
NFSv4: nfs_atomic_open() can race when looking up a non-regular file
NFSv4: Handle case where the lookup of a directory fails
NFSv42: Fallocate and clone should also request 'blocks used'
NFSv4: Allow writebacks to request 'blocks used'
SUNRPC: use default_groups in kobj_type
NFS: use default_groups in kobj_type
NFS: Fix the verifier for case sensitive filesystem in nfs_atomic_open()
NFS: Add a helper to remove case-insensitive aliases
...
Pull signal/exit/ptrace updates from Eric Biederman:
"This set of changes deletes some dead code, makes a lot of cleanups
which hopefully make the code easier to follow, and fixes bugs found
along the way.
The end-game which I have not yet reached yet is for fatal signals
that generate coredumps to be short-circuit deliverable from
complete_signal, for force_siginfo_to_task not to require changing
userspace configured signal delivery state, and for the ptrace stops
to always happen in locations where we can guarantee on all
architectures that the all of the registers are saved and available on
the stack.
Removal of profile_task_ext, profile_munmap, and profile_handoff_task
are the big successes for dead code removal this round.
A bunch of small bug fixes are included, as most of the issues
reported were small enough that they would not affect bisection so I
simply added the fixes and did not fold the fixes into the changes
they were fixing.
There was a bug that broke coredumps piped to systemd-coredump. I
dropped the change that caused that bug and replaced it entirely with
something much more restrained. Unfortunately that required some
rebasing.
Some successes after this set of changes: There are few enough calls
to do_exit to audit in a reasonable amount of time. The lifetime of
struct kthread now matches the lifetime of struct task, and the
pointer to struct kthread is no longer stored in set_child_tid. The
flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
removed. Issues where task->exit_code was examined with
signal->group_exit_code should been examined were fixed.
There are several loosely related changes included because I am
cleaning up and if I don't include them they will probably get lost.
The original postings of these changes can be found at:
https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.orghttps://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.orghttps://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org
I trimmed back the last set of changes to only the obviously correct
once. Simply because there was less time for review than I had hoped"
* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
ptrace/m68k: Stop open coding ptrace_report_syscall
ptrace: Remove unused regs argument from ptrace_report_syscall
ptrace: Remove second setting of PT_SEIZED in ptrace_attach
taskstats: Cleanup the use of task->exit_code
exit: Use the correct exit_code in /proc/<pid>/stat
exit: Fix the exit_code for wait_task_zombie
exit: Coredumps reach do_group_exit
exit: Remove profile_handoff_task
exit: Remove profile_task_exit & profile_munmap
signal: clean up kernel-doc comments
signal: Remove the helper signal_group_exit
signal: Rename group_exit_task group_exec_task
coredump: Stop setting signal->group_exit_task
signal: Remove SIGNAL_GROUP_COREDUMP
signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
signal: Make coredump handling explicit in complete_signal
signal: Have prepare_signal detect coredumps using signal->core_state
signal: Have the oom killer detect coredumps using signal->core_state
exit: Move force_uaccess back into do_exit
exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
...
- Bruce steps down as NFSD maintainer
- Prepare for dynamic nfsd thread management
- More work on supporting re-exporting NFS mounts
- One fs/locks patch on behalf of Jeff Layton
Notable bug fixes:
- Fix zero-length NFSv3 WRITEs
- Fix directory cinfo on FS's that do not support iversion
- Fix WRITE verifiers for stable writes
- Fix crash on COPY_NOTIFY with a special state ID
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Merge tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd updates from Chuck Lever:
"Bruce has announced he is leaving Red Hat at the end of the month and
is stepping back from his role as NFSD co-maintainer. As a result,
this includes a patch removing him from the MAINTAINERS file.
There is one patch in here that Jeff Layton was carrying in the locks
tree. Since he had only one for this cycle, he asked us to send it to
you via the nfsd tree.
There continues to be 0-day reports from Robert Morris @MIT. This time
we include a fix for a crash in the COPY_NOTIFY operation.
Highlights:
- Bruce steps down as NFSD maintainer
- Prepare for dynamic nfsd thread management
- More work on supporting re-exporting NFS mounts
- One fs/locks patch on behalf of Jeff Layton
Notable bug fixes:
- Fix zero-length NFSv3 WRITEs
- Fix directory cinfo on FS's that do not support iversion
- Fix WRITE verifiers for stable writes
- Fix crash on COPY_NOTIFY with a special state ID"
* tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (51 commits)
SUNRPC: Fix sockaddr handling in svcsock_accept_class trace points
SUNRPC: Fix sockaddr handling in the svc_xprt_create_error trace point
fs/locks: fix fcntl_getlk64/fcntl_setlk64 stub prototypes
nfsd: fix crash on COPY_NOTIFY with special stateid
MAINTAINERS: remove bfields
NFSD: Move fill_pre_wcc() and fill_post_wcc()
Revert "nfsd: skip some unnecessary stats in the v4 case"
NFSD: Trace boot verifier resets
NFSD: Rename boot verifier functions
NFSD: Clean up the nfsd_net::nfssvc_boot field
NFSD: Write verifier might go backwards
nfsd: Add a tracepoint for errors in nfsd4_clone_file_range()
NFSD: De-duplicate net_generic(nf->nf_net, nfsd_net_id)
NFSD: De-duplicate net_generic(SVC_NET(rqstp), nfsd_net_id)
NFSD: Clean up nfsd_vfs_write()
nfsd: Replace use of rwsem with errseq_t
NFSD: Fix verifier returned in stable WRITEs
nfsd: Retry once in nfsd_open on an -EOPENSTALE return
nfsd: Add errno mapping for EREMOTEIO
nfsd: map EBADF
...
For each location returned in FS_LOCATION query, establish a
transport to the server, send EXCHANGE_ID and test for trunking,
if successful, add the transport to the exiting client.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
An fs_location attribute returns a string that can be ipv4, ipv6,
or DNS name. An ip location can have a port appended to it and if
no port is present a default port needs to be set. If rpc_pton()
fails to parse, try calling rpc_uaddr2socaddr() that can convert
an universal address.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Make nfs_parse_server_name available outside of nfs4namespace.c.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Query the server for other possible trunkable locations for a given
file system on a 4.1+ mount.
v2:
-- added missing static to nfs4_discover_trunking,
reported by the kernel test robot
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'fscache-rewrite-20220111' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull fscache rewrite from David Howells:
"This is a set of patches that rewrites the fscache driver and the
cachefiles driver, significantly simplifying the code compared to
what's upstream, removing the complex operation scheduling and object
state machine in favour of something much smaller and simpler.
The series is structured such that the first few patches disable
fscache use by the network filesystems using it, remove the cachefiles
driver entirely and as much of the fscache driver as can be got away
with without causing build failures in the network filesystems.
The patches after that recreate fscache and then cachefiles,
attempting to add the pieces in a logical order. Finally, the
filesystems are reenabled and then the very last patch changes the
documentation.
[!] Note: I have dropped the cifs patch for the moment, leaving local
caching in cifs disabled. I've been having trouble getting that
working. I think I have it done, but it needs more testing (there
seem to be some test failures occurring with v5.16 also from
xfstests), so I propose deferring that patch to the end of the
merge window.
WHY REWRITE?
============
Fscache's operation scheduling API was intended to handle sequencing
of cache operations, which were all required (where possible) to run
asynchronously in parallel with the operations being done by the
network filesystem, whilst allowing the cache to be brought online and
offline and to interrupt service for invalidation.
With the advent of the tmpfile capacity in the VFS, however, an
opportunity arises to do invalidation much more simply, without having
to wait for I/O that's actually in progress: Cachefiles can simply
create a tmpfile, cut over the file pointer for the backing object
attached to a cookie and abandon the in-progress I/O, dismissing it
upon completion.
Future work here would involve using Omar Sandoval's vfs_link() with
AT_LINK_REPLACE[1] to allow an extant file to be displaced by a new
hard link from a tmpfile as currently I have to unlink the old file
first.
These patches can also simplify the object state handling as I/O
operations to the cache don't all have to be brought to a stop in
order to invalidate a file. To that end, and with an eye on to writing
a new backing cache model in the future, I've taken the opportunity to
simplify the indexing structure.
I've separated the index cookie concept from the file cookie concept
by C type now. The former is now called a "volume cookie" (struct
fscache_volume) and there is a container of file cookies. There are
then just the two levels. All the index cookie levels are collapsed
into a single volume cookie, and this has a single printable string as
a key. For instance, an AFS volume would have a key of something like
"afs,example.com,1000555", combining the filesystem name, cell name
and volume ID. This is freeform, but must not have '/' chars in it.
I've also eliminated all pointers back from fscache into the network
filesystem. This required the duplication of a little bit of data in
the cookie (cookie key, coherency data and file size), but it's not
actually that much. This gets rid of problems with making sure we keep
netfs data structures around so that the cache can access them.
These patches mean that most of the code that was in the drivers
before is simply gone and those drivers are now almost entirely new
code. That being the case, there doesn't seem any particular reason to
try and maintain bisectability across it. Further, there has to be a
point in the middle where things are cut over as there's a single
point everything has to go through (ie. /dev/cachefiles) and it can't
be in use by two drivers at once.
ISSUES YET OUTSTANDING
======================
There are some issues still outstanding, unaddressed by this patchset,
that will need fixing in future patchsets, but that don't stop this
series from being usable:
(1) The cachefiles driver needs to stop using the backing filesystem's
metadata to store information about what parts of the cache are
populated. This is not reliable with modern extent-based
filesystems.
Fixing this is deferred to a separate patchset as it involves
negotiation with the network filesystem and the VM as to how much
data to download to fulfil a read - which brings me on to (2)...
(2) NFS (and CIFS with the dropped patch) do not take account of how
the cache would like I/O to be structured to meet its granularity
requirements. Previously, the cache used page granularity, which
was fine as the network filesystems also dealt in page
granularity, and the backing filesystem (ext4, xfs or whatever)
did whatever it did out of sight. However, we now have folios to
deal with and the cache will now have to store its own metadata to
track its contents.
The change I'm looking at making for cachefiles is to store
content bitmaps in one or more xattrs and making a bit in the map
correspond to something like a 256KiB block. However, the size of
an xattr and the fact that they have to be read/updated in one go
means that I'm looking at covering 1GiB of data per 512-byte map
and storing each map in an xattr. Cachefiles has the potential to
grow into a fully fledged filesystem of its very own if I'm not
careful.
However, I'm also looking at changing things even more radically
and going to a different model of how the cache is arranged and
managed - one that's more akin to the way, say, openafs does
things - which brings me on to (3)...
(3) The way cachefilesd does culling is very inefficient for large
caches and it would be better to move it into the kernel if I can
as cachefilesd has to keep asking the kernel if it can cull a
file. Changing the way the backend works would allow this to be
addressed.
BITS THAT MAY BE CONTROVERSIAL
==============================
There are some bits I've added that may be controversial:
(1) I've provided a flag, S_KERNEL_FILE, that cachefiles uses to check
if a files is already being used by some other kernel service
(e.g. a duplicate cachefiles cache in the same directory) and
reject it if it is. This isn't entirely necessary, but it helps
prevent accidental data corruption.
I don't want to use S_SWAPFILE as that has other effects, but
quite possibly swapon() should set S_KERNEL_FILE too.
Note that it doesn't prevent userspace from interfering, though
perhaps it should. (I have made it prevent a marked directory from
being rmdir-able).
(2) Cachefiles wants to keep the backing file for a cookie open whilst
we might need to write to it from network filesystem writeback.
The problem is that the network filesystem unuses its cookie when
its file is closed, and so we have nothing pinning the cachefiles
file open and it will get closed automatically after a short time
to avoid EMFILE/ENFILE problems.
Reopening the cache file, however, is a problem if this is being
done due to writeback triggered by exit(). Some filesystems will
oops if we try to open a file in that context because they want to
access current->fs or suchlike.
To get around this, I added the following:
(A) An inode flag, I_PINNING_FSCACHE_WB, to be set on a network
filesystem inode to indicate that we have a usage count on the
cookie caching that inode.
(B) A flag in struct writeback_control, unpinned_fscache_wb, that
is set when __writeback_single_inode() clears the last dirty
page from i_pages - at which point it clears
I_PINNING_FSCACHE_WB and sets this flag.
This has to be done here so that clearing I_PINNING_FSCACHE_WB
can be done atomically with the check of PAGECACHE_TAG_DIRTY
that clears I_DIRTY_PAGES.
(C) A function, fscache_set_page_dirty(), which if it is not set,
sets I_PINNING_FSCACHE_WB and calls fscache_use_cookie() to
pin the cache resources.
(D) A function, fscache_unpin_writeback(), to be called by
->write_inode() to unuse the cookie.
(E) A function, fscache_clear_inode_writeback(), to be called when
the inode is evicted, before clear_inode() is called. This
cleans up any lingering I_PINNING_FSCACHE_WB.
The network filesystem can then use these tools to make sure that
fscache_write_to_cache() can write locally modified data to the
cache as well as to the server.
For the future, I'm working on write helpers for netfs lib that
should allow this facility to be removed by keeping track of the
dirty regions separately - but that's incomplete at the moment and
is also going to be affected by folios, one way or another, since
it deals with pages"
Link: https://lore.kernel.org/all/510611.1641942444@warthog.procyon.org.uk/
Tested-by: Dominique Martinet <asmadeus@codewreck.org> # 9p
Tested-by: kafs-testing@auristor.com # afs
Tested-by: Jeff Layton <jlayton@kernel.org> # ceph
Tested-by: Dave Wysochanski <dwysocha@redhat.com> # nfs
Tested-by: Daire Byrne <daire@dneg.com> # nfs
* tag 'fscache-rewrite-20220111' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (67 commits)
9p, afs, ceph, nfs: Use current_is_kswapd() rather than gfpflags_allow_blocking()
fscache: Add a tracepoint for cookie use/unuse
fscache: Rewrite documentation
ceph: add fscache writeback support
ceph: conversion to new fscache API
nfs: Implement cache I/O by accessing the cache directly
nfs: Convert to new fscache volume/cookie API
9p: Copy local writes to the cache when writing to the server
9p: Use fscache indexing rewrite and reenable caching
afs: Skip truncation on the server of data we haven't written yet
afs: Copy local writes to the cache when writing to the server
afs: Convert afs to use the new fscache API
fscache, cachefiles: Display stat of culling events
fscache, cachefiles: Display stats of no-space events
cachefiles: Allow cachefiles to actually function
fscache, cachefiles: Store the volume coherency data
cachefiles: Implement the I/O routines
cachefiles: Implement cookie resize for truncate
cachefiles: Implement begin and end I/O operation
cachefiles: Implement backing file wrangling
...
Define and store if server returns it supports fs_locations attribute
as a capability.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Remove the check for the zero length fs_locations reply in the
xdr decoding, and instead check for that in the migration code.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In 9p, afs ceph, and nfs, gfpflags_allow_blocking() (which wraps a
test for __GFP_DIRECT_RECLAIM being set) is used to determine if
->releasepage() should wait for the completion of a DIO write to fscache
with something like:
if (folio_test_fscache(folio)) {
if (!gfpflags_allow_blocking(gfp) || !(gfp & __GFP_FS))
return false;
folio_wait_fscache(folio);
}
Instead, current_is_kswapd() should be used instead.
Note that this is based on a patch originally by Zhaoyang Huang[1]. In
addition to extending it to the other network filesystems and putting it on
top of my fscache rewrite, it also needs to include linux/swap.h in a bunch
of places. Can current_is_kswapd() be moved to linux/mm.h?
Changes
=======
ver #5:
- Dropping the changes for cifs.
Originally-signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Co-developed-by: David Howells <dhowells@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
cc: Dominique Martinet <asmadeus@codewreck.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Steve French <smfrench@gmail.com>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: linux-cachefs@redhat.com
cc: v9fs-developer@lists.sourceforge.net
cc: linux-afs@lists.infradead.org
cc: ceph-devel@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/1638952658-20285-1-git-send-email-huangzhaoyang@gmail.com/ [1]
Link: https://lore.kernel.org/r/164021590773.640689.16777975200823659231.stgit@warthog.procyon.org.uk/ # v4
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
NFSv4.1 supports an optional lock notification feature which notifies
the client when a lock comes available. (Normally NFSv4 clients just
poll for locks if necessary.) To make that work, we need to request a
blocking lock from the filesystem.
We turned that off for NFS in commit f657f8eef3 ("nfs: don't atempt
blocking locks on nfs reexports") [sic] because it actually blocks the
nfsd thread while waiting for the lock.
Thanks to Vasily Averin for pointing out that NFS isn't the only
filesystem with that problem.
Any filesystem that leaves ->lock NULL will use posix_lock_file(), which
does the right thing. Simplest is just to assume that any filesystem
that defines its own ->lock is not safe to request a blocking lock from.
So, this patch mostly reverts commit f657f8eef3 ("nfs: don't atempt
blocking locks on nfs reexports") [sic] and commit b840be2f00 ("lockd:
don't attempt blocking locks on nfs reexports"), and instead uses a
check of ->lock (Vasily's suggestion) to decide whether to support
blocking lock notifications on a given filesystem. Also add a little
documentation.
Perhaps someday we could add back an export flag later to allow
filesystems with "good" ->lock methods to support blocking lock
notifications.
Reported-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ cel: Description rewritten to address checkpatch nits ]
[ cel: Fixed warning when SUNRPC debugging is disabled ]
[ cel: Fixed NULL check ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Vasily Averin <vvs@virtuozzo.com>
If the file type changes back to being a regular file on the server
between the failed OPEN and our LOOKUP, then we need to re-run the OPEN.
Fixes: 0dd2b474d0 ("nfs: implement i_op->atomic_open()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the application sets the O_DIRECTORY flag, and tries to open a
regular file, nfs_atomic_open() will punt to doing a regular lookup.
If the server then returns a regular file, we will happily return a
file descriptor with uninitialised open state.
The fix is to return the expected ENOTDIR error in these cases.
Reported-by: Lyu Tao <tao.lyu@epfl.ch>
Fixes: 0dd2b474d0 ("nfs: implement i_op->atomic_open()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Both fallocate and clone can end up updating the blocks used attribute.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When doing a non-pNFS write, allow the writeback code to specify that it
also needs to update 'blocks used'.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field. Move the NFS code to use default_groups field which has been the
preferred way since aa30f47cf6 ("kobject: Add support for default
attribute groups to kobj_type") so that we can soon get rid of the
obsolete default_attrs field.
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When dealing with case insensitive names, the client has no idea how the
server performs the mapping, so cannot collapse the dentries into a
single representative. So both rename and unlink need to deal with the
fact that there could be several dentries representing the file, and
have to somehow force them to be revalidated. Use d_prune_aliases() as a
big hammer approach.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we create a file, rename it, or hardlink it, then we need to assume
that cached negative dentries need to be revalidated.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the directory contents change, we cannot rely on the negative dentry
being cacheable.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add capabilities to allow the NFS client to recognise when it is dealing
with case insensitive and case preserving filesystems.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When decode_devicenotify_args() exits with no entries, we need to
ensure that the struct cb_devicenotifyargs is initialised to
{ 0, NULL } in order to avoid problems in
nfs4_callback_devicenotify().
Reported-by: <rtm@csail.mit.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
kstrdup() returns NULL when some internal memory errors happen, it is
better to check the return value of it so to catch the memory error in
time.
Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When the bitmask of the attributes doesn't include the security label,
don't bother printing it. Since the label might not be null terminated,
adjust the printing format accordingly.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].
Refactor the code a bit according to the use of a flexible-array member
in struct nfs4_file_layout_dsaddr instead of a one-element array, and
use the struct_size() helper.
This helps with the ongoing efforts to globally enable -Warray-bounds
and get us closer to being able to tighten the FORTIFY_SOURCE routines
on memcpy().
This issue was found with the help of Coccinelle and audited and fixed,
manually.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.10/process/deprecated.html#zero-length-and-one-element-arrays
Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/109
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Renaming a file is required by POSIX to update the file ctime, so
ensure that the file data is synced to disk so that we don't clobber the
updated ctime by writing back after creating the hard link.
Fixes: f2c2c552f1 ("NFS: Move delegation recall into the NFSv4 callback for rename_setup()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Creating a hard link is required by POSIX to update the file ctime, so
ensure that the file data is synced to disk so that we don't clobber the
updated ctime by writing back after creating the hard link.
Fixes: 9f76827287 ("NFS: Move the delegation return down into nfs4_proc_link()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Storing the 'struct cred *' in nfs_access_entry is problematic.
An active 'cred' can keep a 'struct key *' active, and a quota is
imposed on the number of such keys that a user can maintain.
Cached 'nfs_access_entry' structs have indefinite lifetime, and having
these keep 'struct key's alive imposes on that quota.
So remove the 'struct cred *' and replace it with the fields we need:
kuid_t, kgid_t, and struct group_info *
This makes the 'struct nfs_access_entry' 64 bits larger.
New function "access_cmp" is introduced which is identical to
cred_fscmp() except that the second arg is an 'nfs_access_entry', rather
than a 'cred'
Fixes: b68572e07c ("NFS: change access cache to use 'struct cred'.")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Storing the 'struct cred *' in nfs_access_entry is problematic.
An active 'cred' can keep a 'struct key *' active, and a quota is
imposed on the number of such keys that a user can maintain.
Cached 'nfs_access_entry' structs have indefinite lifetime, and having
these keep 'struct key's alive imposes on that quota.
So a future patch will remove the ->cred ref from nfs_access_entry.
To prepare, change various functions to not assume there is a 'cred' in
the nfs_access_entry, but to pass the cred around explicitly.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently the nfs_access_get_cached family of functions report a
'struct nfs_access_entry' as the result, with both .mask and .cred set.
However the .cred is never used. This is probably good and there is no
guarantee that it won't be freed before use.
Change to only report the 'mask' - as this is all that is used or needed.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.
There's a lot of missing includes this was masking. Primarily
in networking tho, this time.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
Now that thread management is consistent there is no need for
nfs-callback to use svc_create_pooled() as introduced in Commit
df807fffaa ("NFSv4.x/callback: Create the callback service through
svc_create_pooled"). So switch back to svc_create().
If service pools were configured, but the number of threads were left at
'1', nfs callback may not work reliably when svc_create_pooled() is used.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The ->svo_setup callback serves no purpose. It is always called from
within the same module that chooses which callback is needed. So
discard it and call the relevant function directly.
Now that svc_set_num_threads() is no longer used remove it and rename
svc_set_num_threads_sync() to remove the "_sync" suffix.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The use of sv_nrthreads as a general refcount results in clumsy code, as
is seen by various comments needed to explain the situation.
This patch introduces a 'struct kref' and uses that for reference
counting, leaving sv_nrthreads to be a pure count of threads. The kref
is managed particularly in svc_get() and svc_put(), and also nfsd_put();
svc_destroy() now takes a pointer to the embedded kref, rather than to
the serv.
nfsd allows the svc_serv to exist with ->sv_nrhtreads being zero. This
happens when a transport is created before the first thread is started.
To support this, a 'keep_active' flag is introduced which holds a ref on
the svc_serv. This is set when any listening socket is successfully
added (unless there are running threads), and cleared when the number of
threads is set. So when the last thread exits, the nfs_serv will be
destroyed.
The use of 'keep_active' replaces previous code which checked if there
were any permanent sockets.
We no longer clear ->rq_server when nfsd() exits. This was done
to prevent svc_exit_thread() from calling svc_destroy().
Instead we take an extra reference to the svc_serv to prevent
svc_destroy() from being called.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
svc_destroy() is poorly named - it doesn't necessarily destroy the svc,
it might just reduce the ref count.
nfsd_destroy() is poorly named for the same reason.
This patch:
- removes the refcount functionality from svc_destroy(), moving it to
a new svc_put(). Almost all previous callers of svc_destroy() now
call svc_put().
- renames nfsd_destroy() to nfsd_put() and improves the code, using
the new svc_destroy() rather than svc_put()
- removes a few comments that explain the important for balanced
get/put calls. This should be obvious.
The only non-trivial part of this is that svc_destroy() would call
svc_sock_update() on a non-final decrement. It can no longer do that,
and svc_put() isn't really a good place of it. This call is now made
from svc_exit_thread() which seems like a good place. This makes the
call *before* sv_nrthreads is decremented rather than after. This
is not particularly important as the call just sets a flag which
causes sv_nrthreads set be checked later. A subsequent patch will
improve the ordering.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
It is common for 'get' functions to return the object that was 'got',
and there are a couple of places where users of svc_get() would be a
little simpler if svc_get() did that.
Make it so.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Update module_put_and_exit to call kthread_exit instead of do_exit.
Change the name to reflect this change in functionality. All of the
users of module_put_and_exit are causing the current kthread to exit
so this change makes it clear what is happening. There is no
functional change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
