Support for FATTR4_POSIX_ACCESS_ACL and FATTR4_POSIX_DEFAULT_ACL
attributes in subsequent patches allows clients to set both ACL
types simultaneously during SETATTR and file creation. Each ACL
type can succeed or fail independently, requiring the server to
clear individual attribute bits in the reply bitmap when one
fails while the other succeeds.
The existing na_aclerr field cannot distinguish which ACL type
encountered an error. Separate error fields (na_paclerr for
access ACLs, na_dpaclerr for default ACLs) enable the server to
report per-ACL-type failures accurately.
This refactoring also adds validation previously absent: default
ACL processing rejects non-directory targets with EINVAL and
passes NULL to set_posix_acl() when a_count is zero to delete
the ACL. Access ACL processing rejects zero a_count with EINVAL
for ACL_SCOPE_FILE_SYSTEM semantics (the only scope currently
supported).
The changes preserve compatibility with existing NFSv4 ACL code.
NFSv4 ACL conversion (nfs4_acl_nfsv4_to_posix()) never produces
POSIX ACLs with a_count == 0, so the new validation logic only
affects future POSIX ACL attribute handling.
Signed-off-by: Rick Macklem <rmacklem@uoguelph.ca>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
A set of NFSD fixes that arrived just a bit late for the 6.19 merge
window.
Issues reported with v6.19-rc:
- Mark variable __maybe_unused to avoid W=1 build break
Issues that need expedient stable backports:
- NFSv4 file creation neglects setting ACL
- Clear TIME_DELEG in the suppattr_exclcreat bitmap
- Clear SECLABEL in the suppattr_exclcreat bitmap
- Fix memory leak in nfsd_create_serv error paths
- Bound check rq_pages index in inline path
- Return 0 on success from svc_rdma_copy_inline_range
- Use rc_pageoff for memcpy byte offset
- Avoid NULL deref on zero length gss_token in gss_read_proxy_verf
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Merge tag 'nfsd-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd fixes from Chuck Lever:
"A set of NFSD fixes that arrived just a bit late for the 6.19 merge
window.
Regression fixes:
- Mark variable __maybe_unused to avoid W=1 build break
Stable fixes:
- NFSv4 file creation neglects setting ACL
- Clear TIME_DELEG in the suppattr_exclcreat bitmap
- Clear SECLABEL in the suppattr_exclcreat bitmap
- Fix memory leak in nfsd_create_serv error paths
- Bound check rq_pages index in inline path
- Return 0 on success from svc_rdma_copy_inline_range
- Use rc_pageoff for memcpy byte offset
- Avoid NULL deref on zero length gss_token in gss_read_proxy_verf"
* tag 'nfsd-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
NFSD: NFSv4 file creation neglects setting ACL
NFSD: Clear TIME_DELEG in the suppattr_exclcreat bitmap
NFSD: Clear SECLABEL in the suppattr_exclcreat bitmap
nfsd: fix memory leak in nfsd_create_serv error paths
nfsd: Mark variable __maybe_unused to avoid W=1 build break
svcrdma: bound check rq_pages index in inline path
svcrdma: return 0 on success from svc_rdma_copy_inline_range
svcrdma: use rc_pageoff for memcpy byte offset
SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf
An NFSv4 client that sets an ACL with a named principal during file
creation retrieves the ACL afterwards, and finds that it is only a
default ACL (based on the mode bits) and not the ACL that was
requested during file creation. This violates RFC 8881 section
6.4.1.3: "the ACL attribute is set as given".
The issue occurs in nfsd_create_setattr(), which calls
nfsd_attrs_valid() to determine whether to call nfsd_setattr().
However, nfsd_attrs_valid() checks only for iattr changes and
security labels, but not POSIX ACLs. When only an ACL is present,
the function returns false, nfsd_setattr() is skipped, and the
POSIX ACL is never applied to the inode.
Subsequently, when the client retrieves the ACL, the server finds
no POSIX ACL on the inode and returns one generated from the file's
mode bits rather than returning the originally-specified ACL.
Reported-by: Aurélien Couderc <aurelien.couderc2002@gmail.com>
Fixes: c0cbe70742 ("NFSD: add posix ACLs to struct nfsd_attrs")
Cc: Roland Mainz <roland.mainz@nrubsig.org>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Mike Snitzer's mechanism for disabling I/O caching introduced in
v6.18 is extended to include using direct I/O. The goal is to
further reduce the memory footprint consumed by NFS clients
accessing large data sets via NFSD.
The NFSD community adopted a maintainer entry profile during this
cycle. See
Documentation/filesystems/nfs/nfsd-maintainer-entry-profile.rst
Work continues on hardening NFSD's implementation of the pNFS block
layout type. This type enables pNFS clients to directly access the
underlying block devices that contain an exported file system,
reducing server overhead and increasing data throughput.
The remaining patches in this pull request are clean-ups and minor
optimizations. Many thanks to the contributors, reviewers, testers,
and bug reporters who participated during the v6.19 NFSD development
cycle.
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Merge tag 'nfsd-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux
Pull nfsd updates from Chuck Lever:
- Mike Snitzer's mechanism for disabling I/O caching introduced in
v6.18 is extended to include using direct I/O. The goal is to further
reduce the memory footprint consumed by NFS clients accessing large
data sets via NFSD.
- The NFSD community adopted a maintainer entry profile during this
cycle. See
Documentation/filesystems/nfs/nfsd-maintainer-entry-profile.rst
- Work continues on hardening NFSD's implementation of the pNFS block
layout type. This type enables pNFS clients to directly access the
underlying block devices that contain an exported file system,
reducing server overhead and increasing data throughput.
- The remaining patches are clean-ups and minor optimizations. Many
thanks to the contributors, reviewers, testers, and bug reporters who
participated during the v6.19 NFSD development cycle.
* tag 'nfsd-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (38 commits)
NFSD: nfsd-io-modes: Separate lists
NFSD: nfsd-io-modes: Wrap shell snippets in literal code blocks
NFSD: Add toctree entry for NFSD IO modes docs
NFSD: add Documentation/filesystems/nfs/nfsd-io-modes.rst
NFSD: Implement NFSD_IO_DIRECT for NFS WRITE
NFSD: Make FILE_SYNC WRITEs comply with spec
NFSD: Add trace point for SCSI fencing operation.
NFSD: use correct reservation type in nfsd4_scsi_fence_client
xdrgen: Don't generate unnecessary semicolon
xdrgen: Fix union declarations
NFSD: don't start nfsd if sv_permsocks is empty
xdrgen: handle _XdrString in union encoder/decoder
xdrgen: Fix the variable-length opaque field decoder template
xdrgen: Make the xdrgen script location-independent
xdrgen: Generalize/harden pathname construction
lockd: don't allow locking on reexported NFSv2/3
MAINTAINERS: add a nfsd blocklayout reviewer
nfsd: Use MD5 library instead of crypto_shash
nfsd: stop pretending that we cache the SEQUENCE reply.
NFS: nfsd-maintainer-entry-profile: Inline function name prefixes
...
Prepare for nfsd_iter_read() to use the DIO alignment stored in
nfsd_file by passing the nfsd_file to nfsd_iter_read() rather than
just the file which is associaed with the nfsd_file.
This means nfsd4_encode_readv() now also needs the nfsd_file rather
than the file. Instead of changing the file arg to be the nfsd_file,
we discard the file arg as the nfsd_file (and indeed the file) is
already available via the "read" argument.
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neil@brown.name>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The filecache infrastructure will only handle S_IFREG files at the
moment. Directory delegations will require adding support for opening
S_IFDIR inodes.
Plumb a "type" argument into nfsd_file_do_acquire() and have all of the
existing callers set it to S_IFREG. Add a new nfsd_file_acquire_dir()
wrapper that nfsd can call to request a nfsd_file that holds a directory
open.
For now, there is no need for a fsnotify_mark for directories, as
CB_NOTIFY is not yet supported. Change nfsd_file_do_acquire() to avoid
allocating one for non-S_IFREG inodes.
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neil@brown.name>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20251111-dir-deleg-ro-v6-14-52f3feebb2f2@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Clean up: The fh_getattr() function is part of NFSD's file handle
API, so relocate it.
I've made it an un-inlined function so that trace points and new
functionality can easily be introduced. That increases the size of
nfsd.ko by about a page on my x86_64 system (out of 26MB; compiled
with -O2).
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: these helpers are part of the NFSD file handle API.
Relocate them to fs/nfsd/nfsfh.h.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
All three call sites do the same thing.
I'm struggling with this a bit, however. struct xdr_buf is an XDR
layer object and unmarshaling a WRITE payload is clearly a task
intended to be done by the proc and xdr functions, not by VFS. This
feels vaguely like a layering violation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
NFSD_MAY_LOCK means a few different things.
- it means that GSS is not required.
- it means that with NFSEXP_NOAUTHNLM, authentication is not required
- it means that OWNER_OVERRIDE is allowed.
None of these are specific to locking, they are specific to the NLM
protocol.
So:
- rename to NFSD_MAY_NLM
- set NFSD_MAY_OWNER_OVERRIDE and NFSD_MAY_BYPASS_GSS in nlm_fopen()
so that NFSD_MAY_NLM doesn't need to imply these.
- move the test on NFSEXP_NOAUTHNLM out of nfsd_permission() and
into fh_verify where other special-case tests on the MAY flags
happen. nfsd_permission() can be called from other places than
fh_verify(), but none of these will have NFSD_MAY_NLM.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Clean up: Commit 65294c1f2c ("nfsd: add a new struct file caching
facility to nfsd") moved the fh_verify() call site out of
nfsd_open(). That was the only user of nfsd_open's @rqstp parameter,
so that parameter can be removed.
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Add server support for bypassing NFS for localhost reads, writes, and
commits. This is only useful when both the client and server are
running on the same host.
If nfsd_open_local_fh() fails then the NFS client will both retry and
fallback to normal network-based read, write and commit operations if
localio is no longer supported.
Care is taken to ensure the same NFS security mechanisms are used
(authentication, etc) regardless of whether localio or regular NFS
access is used. The auth_domain established as part of the traditional
NFS client access to the NFS server is also used for localio. Store
auth_domain for localio in nfsd_uuid_t and transfer it to the client
if it is local to the server.
Relative to containers, localio gives the client access to the network
namespace the server has. This is required to allow the client to
access the server's per-namespace nfsd_net struct.
This commit also introduces the use of NFSD's percpu_ref to interlock
nfsd_destroy_serv and nfsd_open_local_fh, to ensure nn->nfsd_serv is
not destroyed while in use by nfsd_open_local_fh and other LOCALIO
client code.
CONFIG_NFS_LOCALIO enables NFS server support for LOCALIO.
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Co-developed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Co-developed-by: NeilBrown <neilb@suse.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
nfsd_permission(), exp_rdonly(), nfsd_setuser(), and nfsexp_flags()
only ever need the cred out of rqstp, so pass it explicitly instead of
the whole rqstp.
This makes the interfaces cleaner.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When security labeling is enabled, the client can pass a file security
label as part of a create operation for the new file, similar to mode
and other attributes. At present, the security label is received by nfsd
and passed down to nfsd_create_setattr(), but nfsd_setattr() is never
called and therefore the label is never set on the new file. This bug
may have been introduced on or around commit d6a97d3f58 ("NFSD:
add security label to struct nfsd_attrs"). Looking at nfsd_setattr()
I am uncertain as to whether the same issue presents for
file ACLs and therefore requires a similar fix for those.
An alternative approach would be to introduce a new LSM hook to set the
"create SID" of the current task prior to the actual file creation, which
would atomically label the new inode at creation time. This would be better
for SELinux and a similar approach has been used previously
(see security_dentry_create_files_as) but perhaps not usable by other LSMs.
Reproducer:
1. Install a Linux distro with SELinux - Fedora is easiest
2. git clone https://github.com/SELinuxProject/selinux-testsuite
3. Install the requisite dependencies per selinux-testsuite/README.md
4. Run something like the following script:
MOUNT=$HOME/selinux-testsuite
sudo systemctl start nfs-server
sudo exportfs -o rw,no_root_squash,security_label localhost:$MOUNT
sudo mkdir -p /mnt/selinux-testsuite
sudo mount -t nfs -o vers=4.2 localhost:$MOUNT /mnt/selinux-testsuite
pushd /mnt/selinux-testsuite/
sudo make -C policy load
pushd tests/filesystem
sudo runcon -t test_filesystem_t ./create_file -f trans_test_file \
-e test_filesystem_filetranscon_t -v
sudo rm -f trans_test_file
popd
sudo make -C policy unload
popd
sudo umount /mnt/selinux-testsuite
sudo exportfs -u localhost:$MOUNT
sudo rmdir /mnt/selinux-testsuite
sudo systemctl stop nfs-server
Expected output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: unconfined_u:object_r:test_filesystem_filetranscon_t:s0
File context is correct
Actual output:
<eliding noise from commands run prior to or after the test itself>
Process context:
unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: system_u:object_r:test_file_t:s0
File context error, expected:
test_filesystem_filetranscon_t
got:
test_file_t
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The main point of the guarded SETATTR is to prevent races with other
WRITE and SETATTR calls. That requires that the check of the guard time
against the inode ctime be done after taking the inode lock.
Furthermore, we need to take into account the 32-bit nature of
timestamps in NFSv3, and the possibility that files may change at a
faster rate than once a second.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Calling fput() directly or though filp_close() from a kernel thread like
nfsd causes the final __fput() (if necessary) to be called from a
workqueue. This means that nfsd is not forced to wait for any work to
complete. If the ->release or ->destroy_inode function is slow for any
reason, this can result in nfsd closing files more quickly than the
workqueue can complete the close and the queue of pending closes can
grow without bounces (30 million has been seen at one customer site,
though this was in part due to a slowness in xfs which has since been
fixed).
nfsd does not need this. It is quite appropriate and safe for nfsd to
do its own close work. There is no reason that close should ever wait
for nfsd, so no deadlock can occur.
It should be safe and sensible to change all fput() calls to
__fput_sync(). However in the interests of caution this patch only
changes two - the two that can be most directly affected by client
behaviour and could occur at high frequency.
- the fput() implicitly in flip_close() is changed to __fput_sync()
by calling get_file() first to ensure filp_close() doesn't do
the final fput() itself. If is where files opened for IO are closed.
- the fput() in nfsd_read() is also changed. This is where directories
opened for readdir are closed.
This ensure that minimal fput work is queued to the workqueue.
This removes the need for the flush_delayed_fput() call in
nfsd_file_close_inode_sync()
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
RQ_SPLICE_OK is a bit of a layering violation. Also, a subsequent
patch is going to provide a mechanism for always disabling splice
reads.
Splicing is an issue only for NFS READs, so refactor nfsd_read() to
check the auth type directly instead of relying on an rq_flag
setting.
The new helper will be added into the NFSv4 read path in a
subsequent patch.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The nfsd_open code handles EOPENSTALE correctly, by retrying the call to
fh_verify() and __nfsd_open(). However the filecache just drops the
error on the floor, and immediately returns nfserr_stale to the caller.
This patch ensures that we propagate the EOPENSTALE code back to
nfsd_file_do_acquire, and that we handle it correctly.
Fixes: 65294c1f2c ("nfsd: add a new struct file caching facility to nfsd")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230911183027.11372-1-trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Accrue the following benefits:
a) Deduplicate this common bit of code.
b) Don't prepare rq_vec for NFSv2 and NFSv3 spliced reads, which
don't use rq_vec. This is already the case for
nfsd4_encode_read().
c) Eventually, converting NFSD's read path to use a bvec iterator
will be simpler.
In the next patch, nfsd_iter_read() will replace nfsd_readv() for
all NFS versions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that we can call into vfs_getattr to get the i_version field, use
that facility to fetch it instead of doing it in nfsd4_change_attribute.
Neil also pointed out recently that IS_I_VERSION directory operations
are always logged, and so we only need to mitigate the rollback problem
on regular files. Also, we don't need to factor in the ctime when
reexporting NFS or Ceph.
Set the STATX_CHANGE_COOKIE (and BTIME) bits in the request when we're
dealing with a v4 request. Then, instead of looking at IS_I_VERSION when
generating the change attr, look at the result mask and only use it if
STATX_CHANGE_COOKIE is set.
Change nfsd4_change_attribute to only factor in the ctime if it's a
regular file and the fs doesn't advertise STATX_ATTR_CHANGE_MONOTONIC.
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
In a moment I'm going to introduce separate nfsd_file types, one of
which is garbage-collected; the other, not. The garbage-collected
variety is to be used by NFSv2 and v3, and the non-garbage-collected
variety is to be used by NFSv4.
nfsd_commit() is invoked by both NFSv3 and NFSv4 consumers. We want
nfsd_commit() to find and use the correct variety of cached
nfsd_file object for the NFS version that is in use.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
nfserrno() is common to all nfs versions, but nfsproc.c is specifically
for NFSv2. Move it to vfs.c, and the prototype to vfs.h.
While we're in here, remove the #ifdef EDQUOT check in this function.
It's apparently a holdover from the initial merge of the nfsd code in
1997. No other place in the kernel checks that that symbol is defined
before using it, so I think we can dispense with it here.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd_create_locked() does not use the "fname" and "flen" arguments, so
drop them from declaration and all callers.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
pacl and dpacl pointers are added to struct nfsd_attrs, which requires
that we have an nfsd_attrs_free() function to free them.
Those nfsv4 functions that can set ACLs now set up these pointers
based on the passed in NFSv4 ACL.
nfsd_setattr() sets the acls as appropriate.
Errors are handled as with security labels.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
nfsd_setattr() now sets a security label if provided, and nfsv4 provides
it in the 'open' and 'create' paths and the 'setattr' path.
If setting the label failed (including because the kernel doesn't
support labels), an error field in 'struct nfsd_attrs' is set, and the
caller can respond. The open/create callers clear
FATTR4_WORD2_SECURITY_LABEL in the returned attr set in this case.
The setattr caller returns the error.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The NFS protocol includes attributes when creating symlinks.
Linux does store attributes for symlinks and allows them to be set,
though they are not used for permission checking.
NFSD currently doesn't set standard (struct iattr) attributes when
creating symlinks, but for NFSv4 it does set ACLs and security labels.
This is inconsistent.
To improve consistency, pass the provided attributes into nfsd_symlink()
and call nfsd_create_setattr() to set them.
NOTE: this results in a behaviour change for all NFS versions when the
client sends non-default attributes with a SYMLINK request. With the
Linux client, the only attributes are:
attr.ia_mode = S_IFLNK | S_IRWXUGO;
attr.ia_valid = ATTR_MODE;
so the final outcome will be unchanged. Other clients might sent
different attributes, and if they did they probably expect them to be
honoured.
We ignore any error from nfsd_create_setattr(). It isn't really clear
what should be done if a file is successfully created, but the
attributes cannot be set. NFS doesn't allow partial success to be
reported. Reporting failure is probably more misleading than reporting
success, so the status is ignored.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
The attributes that nfsd might want to set on a file include 'struct
iattr' as well as an ACL and security label.
The latter two are passed around quite separately from the first, in
part because they are only needed for NFSv4. This leads to some
clumsiness in the code, such as the attributes NOT being set in
nfsd_create_setattr().
We need to keep the directory locked until all attributes are set to
ensure the file is never visibile without all its attributes. This need
combined with the inconsistent handling of attributes leads to more
clumsiness.
As a first step towards tidying this up, introduce 'struct nfsd_attrs'.
This is passed (by reference) to vfs.c functions that work with
attributes, and is assembled by the various nfs*proc functions which
call them. As yet only iattr is included, but future patches will
expand this.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Its only caller always passes S_IFREG as the @type parameter. As an
additional clean-up, add a kerneldoc comment.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that its two callers have their own version-specific instance of
this function, do_nfsd_create() is no longer used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
I'd like to move do_nfsd_create() out of vfs.c. Therefore
nfsd_create_setattr() needs to be made publicly visible.
Note that both call sites in vfs.c commit both the new object and
its parent directory, so just combine those common metadata commits
into nfsd_create_setattr().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Eventually support for NFSv2 in the Linux NFS server is to be
deprecated and then removed.
However, NFSv2 is the "always supported" version that is available
as soon as CONFIG_NFSD is set. Before NFSv2 support can be removed,
we need to choose a different "always supported" version.
This patch removes CONFIG_NFSD_V3 so that NFSv3 is always supported,
as NFSv2 is today. When NFSv2 support is removed, NFSv3 will become
the only "always supported" NFS version.
The defconfigs still need to be updated to remove CONFIG_NFSD_V3=y.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Since, well, forever, the Linux NFS server's nfsd_commit() function
has returned nfserr_inval when the passed-in byte range arguments
were non-sensical.
However, according to RFC 1813 section 3.3.21, NFSv3 COMMIT requests
are permitted to return only the following non-zero status codes:
NFS3ERR_IO
NFS3ERR_STALE
NFS3ERR_BADHANDLE
NFS3ERR_SERVERFAULT
NFS3ERR_INVAL is not included in that list. Likewise, NFS4ERR_INVAL
is not listed in the COMMIT row of Table 6 in RFC 8881.
RFC 7530 does permit COMMIT to return NFS4ERR_INVAL, but does not
specify when it can or should be used.
Instead of dropping or failing a COMMIT request in a byte range that
is not supported, turn it into a valid request by treating one or
both arguments as zero. Offset zero means start-of-file, count zero
means until-end-of-file, so we only ever extend the commit range.
NFS servers are always allowed to commit more and sooner than
requested.
The range check is no longer bounded by NFS_OFFSET_MAX, but rather
by the value that is returned in the maxfilesize field of the NFSv3
FSINFO procedure or the NFSv4 maxfilesize file attribute.
Note that this change results in a new pynfs failure:
CMT4 st_commit.testCommitOverflow : RUNNING
CMT4 st_commit.testCommitOverflow : FAILURE
COMMIT with offset + count overflow should return
NFS4ERR_INVAL, instead got NFS4_OK
IMO the test is not correct as written: RFC 8881 does not allow the
COMMIT operation to return NFS4ERR_INVAL.
Reported-by: Dan Aloni <dan.aloni@vastdata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bruce Fields <bfields@fieldses.org>
Since a clone error commit can cause the boot verifier to change,
we should trace those errors.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ cel: Addressed a checkpatch.pl splat in fs/nfsd/vfs.h ]
This adds the filehandle based functions for the xattr operations
that call in to the vfs layer to do the actual work.
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
[ cel: address checkpatch.pl complaint ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
When doing an unstable write, we need to ensure that we sample the
write verifier before releasing the lock, and allowing a commit to
the same file to proceed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When we have a successful commit, ensure we sample the commit verifier
before releasing the lock.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Needed in order to fix exclusion w.r.t. writes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Needed in order to fix stable writes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Guardtime handling in nfs3 differs between 32-bit and 64-bit
architectures, and uses the deprecated time_t type.
Change it to using time64_t, which behaves the same way on
64-bit and 32-bit architectures, treating the number as an
unsigned 32-bit entity with a range of year 1970 to 2106
consistently, and avoiding the y2038 overflow.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The NFSv4.2 CLONE operation has implicit persistence requirements on the
target file, since there is no protocol requirement that the client issue
a separate operation to persist data.
For that reason, we should call vfs_fsync_range() on the destination file
after a successful call to vfs_clone_file_range().
Fixes: ffa0160a10 ("nfsd: implement the NFSv4.2 CLONE operation")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, the knfsd server assumes that a short read indicates an
end of file. That assumption is incorrect. The short read means that
either we've hit the end of file, or we've hit a read error.
In the case of a read error, the client may want to retry (as per the
implementation recommendations in RFC1813 and RFC7530), but currently it
is being told that it hit an eof.
Move the code to detect eof from version specific code into the generic
nfsd read.
Report eof only in the two following cases:
1) read() returns a zero length short read with no error.
2) the offset+length of the read is >= the file size.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The raparms cache was set up in order to ensure that we carry readahead
information forward from one RPC call to the next. In other words, it
was set up because each RPC call was forced to open a struct file, then
close it, causing the loss of readahead information that is normally
cached in that struct file, and used to keep the page cache filled when
a user calls read() multiple times on the same file descriptor.
Now that we cache the struct file, and reuse it for all the I/O calls
to a given file by a given user, we no longer have to keep a separate
readahead cache.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, NFSv2/3 reads and writes have to open a file, do the read or
write and then close it again for each RPC. This is highly inefficient,
especially when the underlying filesystem has a relatively slow open
routine.
This patch adds a new open file cache to knfsd. Rather than doing an
open for each RPC, the read/write handlers can call into this cache to
see if there is one already there for the correct filehandle and
NFS_MAY_READ/WRITE flags.
If there isn't an entry, then we create a new one and attempt to
perform the open. If there is, then we wait until the entry is fully
instantiated and return it if it is at the end of the wait. If it's
not, then we attempt to take over construction.
Since the main goal is to speed up NFSv2/3 I/O, we don't want to
close these files on last put of these objects. We need to keep them
around for a little while since we never know when the next READ/WRITE
will come in.
Cache entries have a hardcoded 1s timeout, and we have a recurring
workqueue job that walks the cache and purges any entries that have
expired.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Richard Sharpe <richard.sharpe@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
A fuzzer recently triggered lockdep warnings about potential sb_writers
deadlocks caused by fh_want_write().
Looks like we aren't careful to pair each fh_want_write() with an
fh_drop_write().
It's not normally a problem since fh_put() will call fh_drop_write() for
us. And was OK for NFSv3 where we'd do one operation that might call
fh_want_write(), and then put the filehandle.
But an NFSv4 protocol fuzzer can do weird things like call unlink twice
in a compound, and then we get into trouble.
I'm a little worried about this approach of just leaving everything to
fh_put(). But I think there are probably a lot of
fh_want_write()/fh_drop_write() imbalances so for now I think we need it
to be more forgiving.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NFSv4 read compound processing invokes nfsd_splice_read and
nfs_readv directly, so the trace points currently in nfsd_read are
not invoked for NFSv4 reads.
Move the NFSD READ trace points to common helpers so that NFSv4
reads are captured.
Also, record any local I/O error that occurs, the total count of
bytes that were actually returned, and whether splice or vectored
read was used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.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>
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>
This is just cleanup, no change in functionality.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
