pnfs layout type from Christoph Hellwig. The new layout type is a
variant of the block layout which uses SCSI features to offer improved
fencing and device identification.
(Also: note this pull request also includes the client side of SCSI
layout, with Trond's permission.)
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Merge tag 'nfsd-4.6' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Various bugfixes, a RDMA update from Chuck Lever, and support for a
new pnfs layout type from Christoph Hellwig. The new layout type is a
variant of the block layout which uses SCSI features to offer improved
fencing and device identification.
(Also: note this pull request also includes the client side of SCSI
layout, with Trond's permission.)"
* tag 'nfsd-4.6' of git://linux-nfs.org/~bfields/linux:
sunrpc/cache: drop reference when sunrpc_cache_pipe_upcall() detects a race
nfsd: recover: fix memory leak
nfsd: fix deadlock secinfo+readdir compound
nfsd4: resfh unused in nfsd4_secinfo
svcrdma: Use new CQ API for RPC-over-RDMA server send CQs
svcrdma: Use new CQ API for RPC-over-RDMA server receive CQs
svcrdma: Remove close_out exit path
svcrdma: Hook up the logic to return ERR_CHUNK
svcrdma: Use correct XID in error replies
svcrdma: Make RDMA_ERROR messages work
rpcrdma: Add RPCRDMA_HDRLEN_ERR
svcrdma: svc_rdma_post_recv() should close connection on error
svcrdma: Close connection when a send error occurs
nfsd: Lower NFSv4.1 callback message size limit
svcrdma: Do not send Write chunk XDR pad with inline content
svcrdma: Do not write xdr_buf::tail in a Write chunk
svcrdma: Find client-provided write and reply chunks once per reply
nfsd: Update NFS server comments related to RDMA support
nfsd: Fix a memory leak when meeting unsupported state_protect_how4
nfsd4: fix bad bounds checking
nfsd4_cltrack_grace_start() will allocate the memory for grace_start but
when we returned due to error we missed freeing it.
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).
Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The nfsd4_client_tracking_ops structures are never modified, so declare
them as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
These messages, combined with the backtrace they trigger, makes it seem
like a serious problem, though a quick search shows distros marking
it as a "won't fix" non-issue when the problem is reported by users.
The backtrace is overkill, and only really manages to show that if
you follow the code path, you can't really avoid it with bootargs
or configuration settings in the container.
Given that, lets tone it down a bit and get rid of the WARN severity,
and the associated backtrace, so people aren't needlessly alarmed.
Also, lets drop the split printk line, since they are grep unfriendly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If lookup_one_len() failed, nfsd should free those memory allocated for fname.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Convert the following where appropriate:
(1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).
(2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).
(3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more
complicated than it appears as some calls should be converted to
d_can_lookup() instead. The difference is whether the directory in
question is a real dir with a ->lookup op or whether it's a fake dir with
a ->d_automount op.
In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).
Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer. In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.
However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.
There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was
intended for special directory entry types that don't have attached inodes.
The following perl+coccinelle script was used:
use strict;
my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
print "No matches\n";
exit(0);
}
my @cocci = (
'@@',
'expression E;',
'@@',
'',
'- S_ISLNK(E->d_inode->i_mode)',
'+ d_is_symlink(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISDIR(E->d_inode->i_mode)',
'+ d_is_dir(E)',
'',
'@@',
'expression E;',
'@@',
'',
'- S_ISREG(E->d_inode->i_mode)',
'+ d_is_reg(E)' );
my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);
foreach my $file (@callers) {
chomp $file;
print "Processing ", $file, "\n";
system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
die "spatch failed";
}
[AV: overlayfs parts skipped]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull scheduler updates from Ingo Molnar:
"The main changes in this cycle were:
- Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
Hansen)
- Various sched/idle refinements for better idle handling (Nicolas
Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)
- sched/numa updates and optimizations (Rik van Riel)
- sysbench speedup (Vincent Guittot)
- capacity calculation cleanups/refactoring (Vincent Guittot)
- Various cleanups to thread group iteration (Oleg Nesterov)
- Double-rq-lock removal optimization and various refactorings
(Kirill Tkhai)
- various sched/deadline fixes
... and lots of other changes"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
sched/fair: Delete resched_cpu() from idle_balance()
sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
sched: Improve sysbench performance by fixing spurious active migration
sched/x86: Fix up typo in topology detection
x86, sched: Add new topology for multi-NUMA-node CPUs
sched/rt: Use resched_curr() in task_tick_rt()
sched: Use rq->rd in sched_setaffinity() under RCU read lock
sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
sched: Use dl_bw_of() under RCU read lock
sched/fair: Remove duplicate code from can_migrate_task()
sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
sched: print_rq(): Don't use tasklist_lock
sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
sched: Fix the task-group check in tg_has_rt_tasks()
sched/fair: Leverage the idle state info when choosing the "idlest" cpu
sched: Let the scheduler see CPU idle states
sched/deadline: Fix inter- exclusive cpusets migrations
sched/deadline: Clear dl_entity params when setscheduling to different class
sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
...
In the case of v4.0 clients, we may call into the "create" client
tracking operation multiple times (once for each openowner). Upcalling
for each one of those is wasteful and slow however. We can skip doing
further "create" operations after the first one if we know that one has
already been done.
v4.1+ clients generally only call into this function once (on
RECLAIM_COMPLETE), and we can't skip upcalling on the create even if the
STABLE bit is set. Doing so would make it impossible for nfsdcltrack to
lift the grace period early since the timestamp has a different meaning
in the case where the client is expected to issue a RECLAIM_COMPLETE.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
The nfsdcltrack upcall doesn't utilize the NFSD4_CLIENT_STABLE flag,
which basically results in an upcall every time we call into the client
tracking ops.
Change it to set this bit on a successful "check" or "create" request,
and clear it on a "remove" request. Also, check to see if that bit is
set before upcalling on a "check" or "remove" request, and skip
upcalling appropriately, depending on its state.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
In a later patch, we want to add a flag that will allow us to reduce the
need for upcalls. In order to handle that correctly, we'll need to
ensure that racing upcalls for the same client can't occur. In practice
it should be rare for this to occur with a well-behaved client, but it
is possible.
Convert one of the bits in the cl_flags field to be an upcall bitlock,
and use it to ensure that upcalls for the same client are serialized.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
In order to support lifting the grace period early, we must tell
nfsdcltrack what sort of client the "create" upcall is for. We can't
reliably tell if a v4.0 client has completed reclaiming, so we can only
lift the grace period once all the v4.1+ clients have issued a
RECLAIM_COMPLETE and if there are no v4.0 clients.
Also, in order to lift the grace period, we have to tell userland when
the grace period started so that it can tell whether a RECLAIM_COMPLETE
has been issued for each client since then.
Since this is all optional info, we pass it along in environment
variables to the "init" and "create" upcalls. By doing this, we don't
need to revise the upcall format. The UMH upcall can simply make use of
this info if it happens to be present. If it's not then it can just
avoid lifting the grace period early.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
New method - ->iterate(file, ctx). That's the replacement for ->readdir();
it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and
calls dir_emit(ctx, ...) instead of filldir(data, ...). It does *not*
update file->f_pos (or look at it, for that matter); iterate_dir() does the
update.
Note that dir_emit() takes the offset from ctx->pos (and eventually
filldir_t will lose that argument).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
iterate_dir(): new helper, replacing vfs_readdir().
struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull nfsd changes from J Bruce Fields:
"Miscellaneous bugfixes, plus:
- An overhaul of the DRC cache by Jeff Layton. The main effect is
just to make it larger. This decreases the chances of intermittent
errors especially in the UDP case. But we'll need to watch for any
reports of performance regressions.
- Containerized nfsd: with some limitations, we now support
per-container nfs-service, thanks to extensive work from Stanislav
Kinsbursky over the last year."
Some notes about conflicts, since there were *two* non-data semantic
conflicts here:
- idr_remove_all() had been added by a memory leak fix, but has since
become deprecated since idr_destroy() does it for us now.
- xs_local_connect() had been added by this branch to make AF_LOCAL
connections be synchronous, but in the meantime Trond had changed the
calling convention in order to avoid a RCU dereference.
There were a couple of more obvious actual source-level conflicts due to
the hlist traversal changes and one just due to code changes next to
each other, but those were trivial.
* 'for-3.9' of git://linux-nfs.org/~bfields/linux: (49 commits)
SUNRPC: make AF_LOCAL connect synchronous
nfsd: fix compiler warning about ambiguous types in nfsd_cache_csum
svcrpc: fix rpc server shutdown races
svcrpc: make svc_age_temp_xprts enqueue under sv_lock
lockd: nlmclnt_reclaim(): avoid stack overflow
nfsd: enable NFSv4 state in containers
nfsd: disable usermode helper client tracker in container
nfsd: use proper net while reading "exports" file
nfsd: containerize NFSd filesystem
nfsd: fix comments on nfsd_cache_lookup
SUNRPC: move cache_detail->cache_request callback call to cache_read()
SUNRPC: remove "cache_request" argument in sunrpc_cache_pipe_upcall() function
SUNRPC: rework cache upcall logic
SUNRPC: introduce cache_detail->cache_request callback
NFS: simplify and clean cache library
NFS: use SUNRPC cache creation and destruction helper for DNS cache
nfsd4: free_stid can be static
nfsd: keep a checksum of the first 256 bytes of request
sunrpc: trim off trailing checksum before returning decrypted or integrity authenticated buffer
sunrpc: fix comment in struct xdr_buf definition
...
This tracker uses khelper kthread to execute binaries.
Execution itself is done from kthread context - i.e. global root is used.
This is not suitable for containers with own root.
So, disable this tracker for a while.
Note: one of possible solutions can be pass "init" callback to khelper, which
will swap root to desired one.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Use uid_eq(uid, GLOBAL_ROOT_UID) instead of !uid.
Use gid_eq(gid, GLOBAL_ROOT_GID) instead of !gid.
Use uid_eq(uid, INVALID_UID) instead of uid == -1
Use gid_eq(uid, INVALID_GID) instead of gid == -1
Use uid = GLOBAL_ROOT_UID instead of uid = 0;
Use gid = GLOBAL_ROOT_GID instead of gid = 0;
Use !uid_eq(uid1, uid2) instead of uid1 != uid2.
Use !gid_eq(gid1, gid2) instead of gid1 != gid2.
Use uid_eq(uid1, uid2) instead of uid1 == uid2.
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pointer to client tracking operations - client_tracking_ops - have to be
containerized, because different environment can support different trackers
(for example, legacy tracker currently is not suported in container).
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Flag in_grace is a part of client tracking state, which is network namesapce
aware. So let'a replace global static variable with per-net one.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Opening and closing of this file is done in client tracking init and exit
operations.
Client tracking is done in network namespace context already. So let's make
this file opened and closed per network context - this will simlify it's
management.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
That function is only called under nfsd_mutex: we know that because the
only caller is nfsd_svc, via
nfsd_svc
nfsd_startup
nfs4_state_start
nfsd4_client_tracking_init
client_tracking_ops->init == nfsd4_load_reboot_recovery_data
The shared state accessed here includes:
- user_recovery_dirname: used here, modified only by
nfs4_reset_recoverydir, which can be verified to only be
called under nfsd_mutex.
- filesystem state, protected by i_mutex (handwaving slightly
here)
- rec_file, reclaim_str_hashtbl, reclaim_str_hashtbl_size: other
than here, used only from code called from nfsd or laundromat
threads, both of which should be started only after this runs
(see nfsd_svc) and stopped before this could run again (see
nfsd_shutdown, called from nfsd_last_thread).
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Passing net context looks as overkill.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This hash holds nfs4_clients info, which are network namespace aware.
So let's make it allocated per network namespace.
Note: this hash is used only by legacy tracker. So let's allocate hash in
tracker init.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The current code holds on to this list until nfsd is shut down, but it's
never touched once the grace period ends. Release that memory back into
the wild when the grace period ends.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove the cl_recdir field from the nfs4_client struct. Instead, just
compute it on the fly when and if it's needed, which is now only when
the legacy client tracking code is in effect.
The error handling in the legacy client tracker is also changed to
handle the case where md5 is unavailable. In that case, we'll warn
the admin with a KERN_ERR message and disable the client tracking.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When nfsd starts, the legacy reboot recovery code creates a tracking
struct for each directory in the v4recoverydir. When the grace period
ends, it basically does a "readdir" on the directory again, and matches
each dentry in there to an existing client id to see if it should be
removed or not. If the matching client doesn't exist, or hasn't
reclaimed its state then it will remove that dentry.
This is pretty inefficient since it involves doing a lot of hash-bucket
searching. It also means that we have to keep relying on being able to
search for a nfs4_client by md5 hashed cl_recdir name.
Instead, add a pointer to the nfs4_client that indicates the association
between the nfs4_client_reclaim and nfs4_client. When a reclaim operation
comes in, we set the pointer to make that association. On gracedone, the
legacy client tracker will keep the recdir around iff:
1/ there is a reclaim record for the directory
...and...
2/ there's an association between the reclaim record and a client record
-- that is, a create or check operation was performed on the client that
matches that directory.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, it takes a client pointer, but later we're going to need to
search for these records without knowing whether a matching client even
exists.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Let's shoot for removing the nfsdcld upcall in 3.10. Most likely,
no one is actually using it so I don't expect this warning to
fire often (except maybe on misconfigured systems).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The usermodehelper upcall program can then decide to use this info as
a (one-way) transition mechanism to the new scheme. When a "check"
upcall occurs and the client doesn't exist in the database, we can
look to see whether the directory exists. If it does, then we'd add
the client to the database, remove the legacy recdir, and return
success to the kernel to allow the recovery to proceed.
For gracedone, we simply pass the v4recovery "topdir" so that the
upcall can clean it out prior to returning to the kernel.
A module parm is also added to disable the legacy conversion if
the admin chooses.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
First, try to use the new usermodehelper upcall. It should succeed or
fail quickly, so there's little cost to doing so.
If it fails, and the legacy tracking dir exists, use that. If it
doesn't exist then fall back to using nfsdcld.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a new client tracker upcall type that uses call_usermodehelper to
call out to a program. This seems to be the preferred method of
calling out to usermode these days for seldom-called upcalls. It's
simple and doesn't require a running daemon, so it should "just work"
as long as the binary is installed.
The client tracking exit operation is also changed to check for a
NULL pointer before running. The UMH upcall doesn't need to do anything
at module teardown time.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If the credential save fails, then we'll leak our mnt_want_write_file
reference.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When mnt_want_write() starts to handle freezing it will get a full lock
semantics requiring proper lock ordering. So push mnt_want_write() call
consistently outside of i_mutex.
CC: linux-nfs@vger.kernel.org
CC: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull the rest of the nfsd commits from Bruce Fields:
"... and then I cherry-picked the remainder of the patches from the
head of my previous branch"
This is the rest of the original nfsd branch, rebased without the
delegation stuff that I thought really needed to be redone.
I don't like rebasing things like this in general, but in this situation
this was the lesser of two evils.
* 'for-3.5' of git://linux-nfs.org/~bfields/linux: (50 commits)
nfsd4: fix, consolidate client_has_state
nfsd4: don't remove rebooted client record until confirmation
nfsd4: remove some dprintk's and a comment
nfsd4: return "real" sequence id in confirmed case
nfsd4: fix exchange_id to return confirm flag
nfsd4: clarify that renewing expired client is a bug
nfsd4: simpler ordering of setclientid_confirm checks
nfsd4: setclientid: remove pointless assignment
nfsd4: fix error return in non-matching-creds case
nfsd4: fix setclientid_confirm same_cred check
nfsd4: merge 3 setclientid cases to 2
nfsd4: pull out common code from setclientid cases
nfsd4: merge last two setclientid cases
nfsd4: setclientid/confirm comment cleanup
nfsd4: setclientid remove unnecessary terms from a logical expression
nfsd4: move rq_flavor into svc_cred
nfsd4: stricter cred comparison for setclientid/exchange_id
nfsd4: move principal name into svc_cred
nfsd4: allow removing clients not holding state
nfsd4: rearrange exchange_id logic to simplify
...
Kees Cook