Stable bugfixes:
- Revalidate "." and ".." correctly on open
- Avoid RCU usage in tracepoints
- Fix ugly referral attributes
- Fix a typo in nomigration mount option
- Revert "NFS: Move the flock open mode check into nfs_flock()"
Features:
- Implement a stronger send queue accounting system for NFS over RDMA
- Switch some atomics to the new refcount_t type
Other bugfixes and cleanups:
- Clean up access mode bits
- Remove special-case revalidations in nfs_opendir()
- Improve invalidating NFS over RDMA memory for async operations that time out
- Handle NFS over RDMA replies with a worqueue
- Handle NFS over RDMA sends with a workqueue
- Fix up replaying interrupted requests
- Remove dead NFS over RDMA definitions
- Update NFS over RDMA copyright information
- Be more consistent with bool initialization and comparisons
- Mark expected switch fall throughs
- Various sunrpc tracepoint cleanups
- Fix various OPEN races
- Fix a typo in nfs_rename()
- Use common error handling code in nfs_lock_and_join_request()
- Check that some structures are properly cleaned up during net_exit()
- Remove net pointer from dprintk()s
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Merge tag 'nfs-for-4.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Stable bugfixes:
- Revalidate "." and ".." correctly on open
- Avoid RCU usage in tracepoints
- Fix ugly referral attributes
- Fix a typo in nomigration mount option
- Revert "NFS: Move the flock open mode check into nfs_flock()"
Features:
- Implement a stronger send queue accounting system for NFS over RDMA
- Switch some atomics to the new refcount_t type
Other bugfixes and cleanups:
- Clean up access mode bits
- Remove special-case revalidations in nfs_opendir()
- Improve invalidating NFS over RDMA memory for async operations that
time out
- Handle NFS over RDMA replies with a worqueue
- Handle NFS over RDMA sends with a workqueue
- Fix up replaying interrupted requests
- Remove dead NFS over RDMA definitions
- Update NFS over RDMA copyright information
- Be more consistent with bool initialization and comparisons
- Mark expected switch fall throughs
- Various sunrpc tracepoint cleanups
- Fix various OPEN races
- Fix a typo in nfs_rename()
- Use common error handling code in nfs_lock_and_join_request()
- Check that some structures are properly cleaned up during
net_exit()
- Remove net pointer from dprintk()s"
* tag 'nfs-for-4.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (62 commits)
NFS: Revert "NFS: Move the flock open mode check into nfs_flock()"
NFS: Fix typo in nomigration mount option
nfs: Fix ugly referral attributes
NFS: super: mark expected switch fall-throughs
sunrpc: remove net pointer from messages
nfs: remove net pointer from messages
sunrpc: exit_net cleanup check added
nfs client: exit_net cleanup check added
nfs/write: Use common error handling code in nfs_lock_and_join_requests()
NFSv4: Replace closed stateids with the "invalid special stateid"
NFSv4: nfs_set_open_stateid must not trigger state recovery for closed state
NFSv4: Check the open stateid when searching for expired state
NFSv4: Clean up nfs4_delegreturn_done
NFSv4: cleanup nfs4_close_done
NFSv4: Retry NFS4ERR_OLD_STATEID errors in layoutreturn
pNFS: Retry NFS4ERR_OLD_STATEID errors in layoutreturn-on-close
NFSv4: Don't try to CLOSE if the stateid 'other' field has changed
NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.
NFS: Fix a typo in nfs_rename()
NFSv4: Fix open create exclusive when the server reboots
...
atomic_t variables are currently used to implement reference
counters with the following properties:
- counter is initialized to 1 using atomic_set()
- a resource is freed upon counter reaching zero
- once counter reaches zero, its further
increments aren't allowed
- counter schema uses basic atomic operations
(set, inc, inc_not_zero, dec_and_test, etc.)
Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.
The variable nfs_lock_context.count is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Passing the NFS v4 flags into the v3 code seems weird to me, even if
they are defined to the same values. This patch adds in generic flags
to help me feel better
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This field hasn't been used since commit 57b691819e ("NFS: Cache
access checks more aggressively").
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The commit lists can get very large, so using the inode->i_lock can
end up affecting general metadata performance.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This helper will allow to find an existing NFS inode by the file handle
and fattr.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the client receives a fatal server error from nfs_pageio_add_request(),
then we should always truncate the page on which the error occurred.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
By sleeping on a new NFS Unlock-On-Close waitqueue, rpc tasks may wait for
a lock context's iocounter to reach zero. The rpc waitqueue is only woken
when the open_context has the NFS_CONTEXT_UNLOCK flag set in order to
mitigate spurious wake-ups for any iocounter reaching zero.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
When passed GFP flags that allow sleeping (such as
GFP_NOIO), mempool_alloc() will never return NULL, it will
wait until memory is available.
This means that we don't need to handle failure, but that we
do need to ensure one thread doesn't call mempool_alloc()
twice on the one pool without queuing or freeing the first
allocation. If multiple threads did this during times of
high memory pressure, the pool could be exhausted and a
deadlock could result.
pnfs_generic_alloc_ds_commits() attempts to allocate from
the nfs_commit_mempool while already holding an allocation
from that pool. This is not safe. So change
nfs_commitdata_alloc() to take a flag that indicates whether
failure is acceptable.
In pnfs_generic_alloc_ds_commits(), accept failure and
handle it as we currently do. Else where, do not accept
failure, and do not handle it.
Even when failure is acceptable, we want to succeed if
possible. That means both
- using an entry from the pool if there is one
- waiting for direct reclaim is there isn't.
We call mempool_alloc(GFP_NOWAIT) to achieve the first, then
kmem_cache_alloc(GFP_NOIO|__GFP_NORETRY) to achieve the
second. Each of these can fail, but together they do the
best they can without blocking indefinitely.
The objects returned by kmem_cache_alloc() will still be freed
by mempool_free(). This is safe as mempool_alloc() uses
exactly the same function to allocate objects (since the mempool
was created with mempool_create_slab_pool()). The object returned
by mempool_alloc() and kmem_cache_alloc() are indistinguishable
so mempool_free() will handle both identically, either adding to the
pool or calling kmem_cache_free().
Also, don't test for failure when allocating from
nfs_wdata_mempool.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Add a system call to make extended file information available, including
file creation and some attribute flags where available through the
underlying filesystem.
The getattr inode operation is altered to take two additional arguments: a
u32 request_mask and an unsigned int flags that indicate the
synchronisation mode. This change is propagated to the vfs_getattr*()
function.
Functions like vfs_stat() are now inline wrappers around new functions
vfs_statx() and vfs_statx_fd() to reduce stack usage.
========
OVERVIEW
========
The idea was initially proposed as a set of xattrs that could be retrieved
with getxattr(), but the general preference proved to be for a new syscall
with an extended stat structure.
A number of requests were gathered for features to be included. The
following have been included:
(1) Make the fields a consistent size on all arches and make them large.
(2) Spare space, request flags and information flags are provided for
future expansion.
(3) Better support for the y2038 problem [Arnd Bergmann] (tv_sec is an
__s64).
(4) Creation time: The SMB protocol carries the creation time, which could
be exported by Samba, which will in turn help CIFS make use of
FS-Cache as that can be used for coherency data (stx_btime).
This is also specified in NFSv4 as a recommended attribute and could
be exported by NFSD [Steve French].
(5) Lightweight stat: Ask for just those details of interest, and allow a
netfs (such as NFS) to approximate anything not of interest, possibly
without going to the server [Trond Myklebust, Ulrich Drepper, Andreas
Dilger] (AT_STATX_DONT_SYNC).
(6) Heavyweight stat: Force a netfs to go to the server, even if it thinks
its cached attributes are up to date [Trond Myklebust]
(AT_STATX_FORCE_SYNC).
And the following have been left out for future extension:
(7) Data version number: Could be used by userspace NFS servers [Aneesh
Kumar].
Can also be used to modify fill_post_wcc() in NFSD which retrieves
i_version directly, but has just called vfs_getattr(). It could get
it from the kstat struct if it used vfs_xgetattr() instead.
(There's disagreement on the exact semantics of a single field, since
not all filesystems do this the same way).
(8) BSD stat compatibility: Including more fields from the BSD stat such
as creation time (st_btime) and inode generation number (st_gen)
[Jeremy Allison, Bernd Schubert].
(9) Inode generation number: Useful for FUSE and userspace NFS servers
[Bernd Schubert].
(This was asked for but later deemed unnecessary with the
open-by-handle capability available and caused disagreement as to
whether it's a security hole or not).
(10) Extra coherency data may be useful in making backups [Andreas Dilger].
(No particular data were offered, but things like last backup
timestamp, the data version number and the DOS archive bit would come
into this category).
(11) Allow the filesystem to indicate what it can/cannot provide: A
filesystem can now say it doesn't support a standard stat feature if
that isn't available, so if, for instance, inode numbers or UIDs don't
exist or are fabricated locally...
(This requires a separate system call - I have an fsinfo() call idea
for this).
(12) Store a 16-byte volume ID in the superblock that can be returned in
struct xstat [Steve French].
(Deferred to fsinfo).
(13) Include granularity fields in the time data to indicate the
granularity of each of the times (NFSv4 time_delta) [Steve French].
(Deferred to fsinfo).
(14) FS_IOC_GETFLAGS value. These could be translated to BSD's st_flags.
Note that the Linux IOC flags are a mess and filesystems such as Ext4
define flags that aren't in linux/fs.h, so translation in the kernel
may be a necessity (or, possibly, we provide the filesystem type too).
(Some attributes are made available in stx_attributes, but the general
feeling was that the IOC flags were to ext[234]-specific and shouldn't
be exposed through statx this way).
(15) Mask of features available on file (eg: ACLs, seclabel) [Brad Boyer,
Michael Kerrisk].
(Deferred, probably to fsinfo. Finding out if there's an ACL or
seclabal might require extra filesystem operations).
(16) Femtosecond-resolution timestamps [Dave Chinner].
(A __reserved field has been left in the statx_timestamp struct for
this - if there proves to be a need).
(17) A set multiple attributes syscall to go with this.
===============
NEW SYSTEM CALL
===============
The new system call is:
int ret = statx(int dfd,
const char *filename,
unsigned int flags,
unsigned int mask,
struct statx *buffer);
The dfd, filename and flags parameters indicate the file to query, in a
similar way to fstatat(). There is no equivalent of lstat() as that can be
emulated with statx() by passing AT_SYMLINK_NOFOLLOW in flags. There is
also no equivalent of fstat() as that can be emulated by passing a NULL
filename to statx() with the fd of interest in dfd.
Whether or not statx() synchronises the attributes with the backing store
can be controlled by OR'ing a value into the flags argument (this typically
only affects network filesystems):
(1) AT_STATX_SYNC_AS_STAT tells statx() to behave as stat() does in this
respect.
(2) AT_STATX_FORCE_SYNC will require a network filesystem to synchronise
its attributes with the server - which might require data writeback to
occur to get the timestamps correct.
(3) AT_STATX_DONT_SYNC will suppress synchronisation with the server in a
network filesystem. The resulting values should be considered
approximate.
mask is a bitmask indicating the fields in struct statx that are of
interest to the caller. The user should set this to STATX_BASIC_STATS to
get the basic set returned by stat(). It should be noted that asking for
more information may entail extra I/O operations.
buffer points to the destination for the data. This must be 256 bytes in
size.
======================
MAIN ATTRIBUTES RECORD
======================
The following structures are defined in which to return the main attribute
set:
struct statx_timestamp {
__s64 tv_sec;
__s32 tv_nsec;
__s32 __reserved;
};
struct statx {
__u32 stx_mask;
__u32 stx_blksize;
__u64 stx_attributes;
__u32 stx_nlink;
__u32 stx_uid;
__u32 stx_gid;
__u16 stx_mode;
__u16 __spare0[1];
__u64 stx_ino;
__u64 stx_size;
__u64 stx_blocks;
__u64 __spare1[1];
struct statx_timestamp stx_atime;
struct statx_timestamp stx_btime;
struct statx_timestamp stx_ctime;
struct statx_timestamp stx_mtime;
__u32 stx_rdev_major;
__u32 stx_rdev_minor;
__u32 stx_dev_major;
__u32 stx_dev_minor;
__u64 __spare2[14];
};
The defined bits in request_mask and stx_mask are:
STATX_TYPE Want/got stx_mode & S_IFMT
STATX_MODE Want/got stx_mode & ~S_IFMT
STATX_NLINK Want/got stx_nlink
STATX_UID Want/got stx_uid
STATX_GID Want/got stx_gid
STATX_ATIME Want/got stx_atime{,_ns}
STATX_MTIME Want/got stx_mtime{,_ns}
STATX_CTIME Want/got stx_ctime{,_ns}
STATX_INO Want/got stx_ino
STATX_SIZE Want/got stx_size
STATX_BLOCKS Want/got stx_blocks
STATX_BASIC_STATS [The stuff in the normal stat struct]
STATX_BTIME Want/got stx_btime{,_ns}
STATX_ALL [All currently available stuff]
stx_btime is the file creation time, stx_mask is a bitmask indicating the
data provided and __spares*[] are where as-yet undefined fields can be
placed.
Time fields are structures with separate seconds and nanoseconds fields
plus a reserved field in case we want to add even finer resolution. Note
that times will be negative if before 1970; in such a case, the nanosecond
fields will also be negative if not zero.
The bits defined in the stx_attributes field convey information about a
file, how it is accessed, where it is and what it does. The following
attributes map to FS_*_FL flags and are the same numerical value:
STATX_ATTR_COMPRESSED File is compressed by the fs
STATX_ATTR_IMMUTABLE File is marked immutable
STATX_ATTR_APPEND File is append-only
STATX_ATTR_NODUMP File is not to be dumped
STATX_ATTR_ENCRYPTED File requires key to decrypt in fs
Within the kernel, the supported flags are listed by:
KSTAT_ATTR_FS_IOC_FLAGS
[Are any other IOC flags of sufficient general interest to be exposed
through this interface?]
New flags include:
STATX_ATTR_AUTOMOUNT Object is an automount trigger
These are for the use of GUI tools that might want to mark files specially,
depending on what they are.
Fields in struct statx come in a number of classes:
(0) stx_dev_*, stx_blksize.
These are local system information and are always available.
(1) stx_mode, stx_nlinks, stx_uid, stx_gid, stx_[amc]time, stx_ino,
stx_size, stx_blocks.
These will be returned whether the caller asks for them or not. The
corresponding bits in stx_mask will be set to indicate whether they
actually have valid values.
If the caller didn't ask for them, then they may be approximated. For
example, NFS won't waste any time updating them from the server,
unless as a byproduct of updating something requested.
If the values don't actually exist for the underlying object (such as
UID or GID on a DOS file), then the bit won't be set in the stx_mask,
even if the caller asked for the value. In such a case, the returned
value will be a fabrication.
Note that there are instances where the type might not be valid, for
instance Windows reparse points.
(2) stx_rdev_*.
This will be set only if stx_mode indicates we're looking at a
blockdev or a chardev, otherwise will be 0.
(3) stx_btime.
Similar to (1), except this will be set to 0 if it doesn't exist.
=======
TESTING
=======
The following test program can be used to test the statx system call:
samples/statx/test-statx.c
Just compile and run, passing it paths to the files you want to examine.
The file is built automatically if CONFIG_SAMPLES is enabled.
Here's some example output. Firstly, an NFS directory that crosses to
another FSID. Note that the AUTOMOUNT attribute is set because transiting
this directory will cause d_automount to be invoked by the VFS.
[root@andromeda ~]# /tmp/test-statx -A /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:26 Inode: 1703937 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Attributes: 0000000000001000 (-------- -------- -------- -------- -------- -------- ---m---- --------)
Secondly, the result of automounting on that directory.
[root@andromeda ~]# /tmp/test-statx /warthog/data
statx(/warthog/data) = 0
results=7ff
Size: 4096 Blocks: 8 IO Block: 1048576 directory
Device: 00:27 Inode: 2 Links: 125
Access: (3777/drwxrwxrwx) Uid: 0 Gid: 4041
Access: 2016-11-24 09:02:12.219699527+0000
Modify: 2016-11-17 10:44:36.225653653+0000
Change: 2016-11-17 10:44:36.225653653+0000
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When looking at whether or not our dcache is valid, we really don't care
about the general state of the directory attribute cache. Instead, we
we only care about the state of the change attribute.
This fixes a performance issue when the client is responsible for
changing the directory contents; a number of NFSv4 operations will
atomically update the directory change attribute, but may not return
all the other attributes.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It now has only one field and is only used in one structure.
So replaced it in that structure by the field it contains.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
An open file description (struct file) in a given process can be
associated with two different lock owners.
It can have a Posix lock owner which will be different in each process
that has a fd on the file.
It can have a Flock owner which will be the same in all processes.
When searching for a lock stateid to use, we need to consider both of these
owners
So add a new "flock_owner" to the "nfs_open_context" (of which there
is one for each open file description).
This flock_owner does not need to be reference-counted as there is a
1-1 relation between 'struct file' and nfs open contexts,
and it will never be part of a list of contexts. So there is no need
for a 'flock_context' - just the owner is enough.
The io_count included in the (Posix) lock_context provides no
guarantee that all read-aheads that could use the state have
completed, so not supporting it for flock locks in not a serious
problem. Synchronization between flock and read-ahead can be added
later if needed.
When creating an open_context for a non-openning create call, we don't have
a 'struct file' to pass in, so the lock context gets initialized with
a NULL owner, but this will never be used.
The flock_owner is not used at all in this patch, that will come later.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
this field is not used in any important way and probably should
have been removed by
Commit: 8003d3c4aa ("nfs4: treat lock owners as opaque values")
which removed the pid argument from nfs4_get_lock_state.
Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Allow dio requests to be scheduled in parallel, but ensuring that they
do not conflict with buffered I/O.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull vfs cleanups from Al Viro:
"More cleanups from Christoph"
* 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
nfsd: use RWF_SYNC
fs: add RWF_DSYNC aand RWF_SYNC
ceph: use generic_write_sync
fs: simplify the generic_write_sync prototype
fs: add IOCB_SYNC and IOCB_DSYNC
direct-io: remove the offset argument to dio_complete
direct-io: eliminate the offset argument to ->direct_IO
xfs: eliminate the pos variable in xfs_file_dio_aio_write
filemap: remove the pos argument to generic_file_direct_write
filemap: remove pos variables in generic_file_read_iter
use d_alloc_parallel() for sillyunlink/lookup exclusion and
explicit rwsem (nfs_rmdir() being a writer and nfs_call_unlink() -
a reader) for rmdir/sillyunlink one.
That ought to make lookup/readdir/!O_CREAT atomic_open really
parallel on NFS.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually
work, so eliminate the superflous argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
See http: //www.infradead.org/rpr.html
X-Evolution-Source: 1451162204.2173.11@leira.trondhjem.org
Content-Transfer-Encoding: 8bit
Mime-Version: 1.0
We support OFFSET_MAX just fine, so don't round down below it. Also
switch to using min_t to make the helper more readable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Fixes: 433c92379d ("NFS: Clean up nfs_size_to_loff_t()")
Cc: stable@vger.kernel.org # 2.6.23+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
Stable fixes:
- Fix a regression in the SunRPC socket polling code
- Fix the attribute cache revalidation code
- Fix race in __update_open_stateid()
- Fix an lo->plh_block_lgets imbalance in layoutreturn
- Fix an Oopsable typo in ff_mirror_match_fh()
Features:
- pNFS layout recall performance improvements.
- pNFS/flexfiles: Support server-supplied layoutstats sampling period
Bugfixes + cleanups:
- NFSv4: Don't perform cached access checks before we've OPENed the file
- Fix starvation issues with background flushes
- Reclaim writes should be flushed as unstable writes if there are already
entries in the commit lists
- Various bugfixes from Chuck to fix NFS/RDMA send queue ordering problems
- Ensure that we propagate fatal layoutget errors back to the application
- Fixes for sundry flexfiles layoutstats bugs
- Fix files/flexfiles to not cache invalidated layouts in the DS commit buckets
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Merge tag 'nfs-for-4.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable fixes:
- Fix a regression in the SunRPC socket polling code
- Fix the attribute cache revalidation code
- Fix race in __update_open_stateid()
- Fix an lo->plh_block_lgets imbalance in layoutreturn
- Fix an Oopsable typo in ff_mirror_match_fh()
Features:
- pNFS layout recall performance improvements.
- pNFS/flexfiles: Support server-supplied layoutstats sampling period
Bugfixes + cleanups:
- NFSv4: Don't perform cached access checks before we've OPENed the
file
- Fix starvation issues with background flushes
- Reclaim writes should be flushed as unstable writes if there are
already entries in the commit lists
- Various bugfixes from Chuck to fix NFS/RDMA send queue ordering
problems
- Ensure that we propagate fatal layoutget errors back to the
application
- Fixes for sundry flexfiles layoutstats bugs
- Fix files/flexfiles to not cache invalidated layouts in the DS
commit buckets"
* tag 'nfs-for-4.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (68 commits)
NFS: Fix a compile warning about unused variable in nfs_generic_pg_pgios()
NFSv4: Fix a compile warning about no prototype for nfs4_ioctl()
NFS: Use wait_on_atomic_t() for unlock after readahead
SUNRPC: Fixup socket wait for memory
NFSv4.1/pNFS: Cleanup constify struct pnfs_layout_range arguments
NFSv4.1/pnfs: Cleanup copying of pnfs_layout_range structures
NFSv4.1/pNFS: Cleanup pnfs_mark_matching_lsegs_invalid()
NFSv4.1/pNFS: Fix a race in initiate_file_draining()
NFSv4.1/pNFS: pnfs_error_mark_layout_for_return() must always return layout
NFSv4.1/pNFS: pnfs_mark_matching_lsegs_return() should set the iomode
NFSv4.1/pNFS: Use nfs4_stateid_copy for copying stateids
NFSv4.1/pNFS: Don't pass stateids by value to pnfs_send_layoutreturn()
NFS: Relax requirements in nfs_flush_incompatible
NFSv4.1/pNFS: Don't queue up a new commit if the layout segment is invalid
NFS: Allow multiple commit requests in flight per file
NFS/pNFS: Fix up pNFS write reschedule layering violations and bugs
SUNRPC: Fix a missing break in rpc_anyaddr()
pNFS/flexfiles: Fix an Oopsable typo in ff_mirror_match_fh()
NFS: Fix attribute cache revalidation
NFS: Ensure we revalidate attributes before using execute_ok()
...
The use of wait_on_atomic_t() for waiting on I/O to complete before
unlocking allows us to git rid of the NFS_IO_INPROGRESS flag, and thus the
nfs_iocounter's flags member, and finally the nfs_iocounter altogether.
The count of I/O is moved to the lock context, and the counter
increment/decrement functions become simple enough to open-code.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
[Trond: Fix up conflict with existing function nfs_wait_atomic_killable()]
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
* pnfs_generic:
NFSv4.1/pNFS: Cleanup constify struct pnfs_layout_range arguments
NFSv4.1/pnfs: Cleanup copying of pnfs_layout_range structures
NFSv4.1/pNFS: Cleanup pnfs_mark_matching_lsegs_invalid()
NFSv4.1/pNFS: Fix a race in initiate_file_draining()
NFSv4.1/pNFS: pnfs_error_mark_layout_for_return() must always return layout
NFSv4.1/pNFS: pnfs_mark_matching_lsegs_return() should set the iomode
NFSv4.1/pNFS: Use nfs4_stateid_copy for copying stateids
NFSv4.1/pNFS: Don't pass stateids by value to pnfs_send_layoutreturn()
NFS: Relax requirements in nfs_flush_incompatible
NFSv4.1/pNFS: Don't queue up a new commit if the layout segment is invalid
NFS: Allow multiple commit requests in flight per file
NFS/pNFS: Fix up pNFS write reschedule layering violations and bugs
NFSv4: List stateid information in the callback tracepoints
NFSv4.1/pNFS: Don't return NFS4ERR_DELAY unnecessarily in CB_LAYOUTRECALL
NFSv4.1/pNFS: Ensure we enforce RFC5661 Section 12.5.5.2.1
pNFS: If we have to delay the layout callback, mark the layout for return
NFSv4.1/pNFS: Add a helper to mark the layout as returned
pNFS: Ensure nfs4_layoutget_prepare returns the correct error
Allow synchronous RPC calls to wait for pending RPC calls to finish,
but also allow asynchronous ones to just fire off another commit.
With this patch, the xfstests generic/074 test completes in 226s
instead of 242s
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Instead of dropping pages when write fails, only do it when
we get fatal failure in launder_page write back.
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
based upon the corresponding patch from Neil's March patchset,
again with kmap-related horrors removed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
And call nfs_file_clear_open_context() directly. This makes it obvious
that nfs_file_release() will always return 0.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
I'm not aware of any existing bugs around this, but the expectation is
that nfs_mark_for_revalidate() should always force a revalidation of
the cached metadata.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There is no need to report concurrently.
Reviewed-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
Stable patches:
- Fix a regression in /proc/self/mountstats
- Fix the pNFS flexfiles O_DIRECT support
- Fix high load average due to callback thread sleeping
Bugfixes:
- Various patches to fix the pNFS layoutcommit support
- Do not cache pNFS deviceids unless server notifications are enabled
- Fix a SUNRPC transport reconnection regression
- make debugfs file creation failure non-fatal in SUNRPC
- Another fix for circular directory warnings on NFSv4 "junctioned" mountpoints
- Fix locking around NFSv4.2 fallocate() support
- Truncating NFSv4 file opens should also sync O_DIRECT writes
- Prevent infinite loop in rpcrdma_ep_create()
Features:
- Various improvements to the RDMA transport code's handling of memory
registration
- Various code cleanups
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Merge tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Another set of mainly bugfixes and a couple of cleanups. No new
functionality in this round.
Highlights include:
Stable patches:
- Fix a regression in /proc/self/mountstats
- Fix the pNFS flexfiles O_DIRECT support
- Fix high load average due to callback thread sleeping
Bugfixes:
- Various patches to fix the pNFS layoutcommit support
- Do not cache pNFS deviceids unless server notifications are enabled
- Fix a SUNRPC transport reconnection regression
- make debugfs file creation failure non-fatal in SUNRPC
- Another fix for circular directory warnings on NFSv4 "junctioned"
mountpoints
- Fix locking around NFSv4.2 fallocate() support
- Truncating NFSv4 file opens should also sync O_DIRECT writes
- Prevent infinite loop in rpcrdma_ep_create()
Features:
- Various improvements to the RDMA transport code's handling of
memory registration
- Various code cleanups"
* tag 'nfs-for-4.1-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (55 commits)
fs/nfs: fix new compiler warning about boolean in switch
nfs: Remove unneeded casts in nfs
NFS: Don't attempt to decode missing directory entries
Revert "nfs: replace nfs_add_stats with nfs_inc_stats when add one"
NFS: Rename idmap.c to nfs4idmap.c
NFS: Move nfs_idmap.h into fs/nfs/
NFS: Remove CONFIG_NFS_V4 checks from nfs_idmap.h
NFS: Add a stub for GETDEVICELIST
nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes
nfs: fix DIO good bytes calculation
nfs: Fetch MOUNTED_ON_FILEID when updating an inode
sunrpc: make debugfs file creation failure non-fatal
nfs: fix high load average due to callback thread sleeping
NFS: Reduce time spent holding the i_mutex during fallocate()
NFS: Don't zap caches on fallocate()
xprtrdma: Make rpcrdma_{un}map_one() into inline functions
xprtrdma: Handle non-SEND completions via a callout
xprtrdma: Add "open" memreg op
xprtrdma: Add "destroy MRs" memreg op
xprtrdma: Add "reset MRs" memreg op
...
When invalidating the page cache for a regular file, we want to first
sync all dirty data to disk and then call invalidate_inode_pages2().
The latter relies on nfs_launder_page() and nfs_release_page() to deal
respectively with dirty pages, and unstable written pages.
When commit 9590544694 ("NFS: avoid deadlocks with loop-back mounted
NFS filesystems.") changed the behaviour of nfs_release_page(), then it
made it possible for invalidate_inode_pages2() to fail with an EBUSY.
Unfortunately, that error is then propagated back to read().
Let's therefore work around the problem for now by protecting the call
to sync the data and invalidate_inode_pages2() so that they are atomic
w.r.t. the addition of new writes.
Later on, we can revisit whether or not we still need nfs_launder_page()
and nfs_release_page().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ensure that other operations that race with our write RPC calls
cannot revert the file size updates that were made on the server.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Ensure that other operations which raced with our setattr RPC call
cannot revert the file attribute changes that were made on the server.
To do so, we artificially bump the attribute generation counter on
the inode so that all calls to nfs_fattr_init() that precede ours
will be dropped.
The motivation for the patch came from Chuck Lever's reports of readaheads
racing with truncate operations and causing the file size to be reverted.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Recent work in the pgio layer made it possible for there to be more than one
request per page. This caused a subtle change in commit behavior, because
write.c:nfs_commit_unstable_pages compares the number of *pages* waiting for
writeback against the number of requests on a commit list to choose when to
send a COMMIT in a non-blocking flush.
This is probably hard to hit in normal operation - you have to be using
rsize/wsize < PAGE_SIZE, or pnfs with lots of boundaries that are not page
aligned to have a noticeable change in behavior.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull core block layer changes from Jens Axboe:
"This is the core block IO pull request for 3.18. Apart from the new
and improved flush machinery for blk-mq, this is all mostly bug fixes
and cleanups.
- blk-mq timeout updates and fixes from Christoph.
- Removal of REQ_END, also from Christoph. We pass it through the
->queue_rq() hook for blk-mq instead, freeing up one of the request
bits. The space was overly tight on 32-bit, so Martin also killed
REQ_KERNEL since it's no longer used.
- blk integrity updates and fixes from Martin and Gu Zheng.
- Update to the flush machinery for blk-mq from Ming Lei. Now we
have a per hardware context flush request, which both cleans up the
code should scale better for flush intensive workloads on blk-mq.
- Improve the error printing, from Rob Elliott.
- Backing device improvements and cleanups from Tejun.
- Fixup of a misplaced rq_complete() tracepoint from Hannes.
- Make blk_get_request() return error pointers, fixing up issues
where we NULL deref when a device goes bad or missing. From Joe
Lawrence.
- Prep work for drastically reducing the memory consumption of dm
devices from Junichi Nomura. This allows creating clone bio sets
without preallocating a lot of memory.
- Fix a blk-mq hang on certain combinations of queue depths and
hardware queues from me.
- Limit memory consumption for blk-mq devices for crash dump
scenarios and drivers that use crazy high depths (certain SCSI
shared tag setups). We now just use a single queue and limited
depth for that"
* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
block: Remove REQ_KERNEL
blk-mq: allocate cpumask on the home node
bio-integrity: remove the needless fail handle of bip_slab creating
block: include func name in __get_request prints
block: make blk_update_request print prefix match ratelimited prefix
blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
block: fix alignment_offset math that assumes io_min is a power-of-2
blk-mq: Make bt_clear_tag() easier to read
blk-mq: fix potential hang if rolling wakeup depth is too high
block: add bioset_create_nobvec()
block: use bio_clone_fast() in blk_rq_prep_clone()
block: misplaced rq_complete tracepoint
sd: Honor block layer integrity handling flags
block: Replace strnicmp with strncasecmp
block: Add T10 Protection Information functions
block: Don't merge requests if integrity flags differ
block: Integrity checksum flag
block: Relocate bio integrity flags
block: Add a disk flag to block integrity profile
block: Add prefix to block integrity profile flags
...
REQ_KERNEL is no longer used. Remove it and drop the redundant uio
argument to nfs_file_direct_{read,write}.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This code is internal to the v3 module, so other parts of the client
shouldn't have any knowledge of it.
nfs3_getxattr(), nfs3_setxattr(), and nfs3_removexattr() no longer exist
anywhere so I remove the declarations while I'm here.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The goal is to create a generic NFS module with code that does not
depend on what versions of NFS are enabled.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The access cache is used during RCU-walk path lookups, so it is best
to avoid locking if possible as taking a lock kills concurrency.
The rbtree is not rcu-safe and cannot easily be made so.
Instead we simply check the last (i.e. most recent) entry on the LRU
list. If this doesn't match, then we return -ECHILD and retry in
lock/refcount mode.
This requires freeing the nfs_access_entry struct with rcu, and
requires using rcu access primatives when adding entries to the lru, and
when examining the last entry.
Calling put_rpccred before kfree_rcu looks a bit odd, but as
put_rpccred already provides rcu protection, we know that the cred will
not actually be freed until the next grace period, so any concurrent
access will be safe.
This patch provides about 5% performance improvement on a stat-heavy
synthetic work load with 4 threads on a 2-core CPU.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
