any thread doing an I/O RPC with a transfer size greater than
NFS_UDPMAXDATA will be hung indefinitely, retrying the RPC.
After a discussion on freebsd-fs@, I decided to add a warning
message for this case, as suggested by Jeremy Chadwick.
Suggested by: freebsd at jdc.parodius.com (Jeremy Chadwick)
MFC after: 2 weeks
NFS clients was reported to freebsd-fs@ under the subject "NFS
corruption in recent HEAD" on Nov. 26, 2011. This problem occurred when
a TCP mounted root fs was changed to using UDP. I believe that this
problem was caused by the change in mnt_stat.f_iosize that occurred
because rsize was decreased to the maximum supported by UDP. This
patch fixes the problem by using v_bufobj.bo_bsize instead of f_iosize,
since the latter is set to f_iosize when the vnode is allocated, but
does not change for a given vnode when f_iosize changes.
Reported by: pjd
Reviewed by: kib
MFC after: 2 weeks
appropriate timestamps. Restore the assertions which verify that
NCF_TS is set when timestamp is asked for.
Reviewed by: jhb (previous version)
MFC after: 2 weeks
we will only trust a positive name cache entry for a specified amount of
time before falling back to a LOOKUP RPC, even if the ctime for the file
handle matches the cached copy in the name cache entry. The timeout is
configured via a new 'nametimeo' mount option and defaults to 60 seconds.
It may be set to zero to disable positive name caching entirely.
Reviewed by: rmacklem
MFC after: 1 week
from TCP to UDP and the rsize/wsize/readdirsize is greater
than NFS_MAXDGRAMDATA, it is possible for a thread doing an
I/O RPC to get stuck repeatedly doing retries. This happens
because the RPC will use a resize/wsize/readdirsize that won't
work for UDP and, as such, it will keep failing indefinitely.
This patch returns an error for this case, to avoid the problem.
A discussion on freebsd-fs@ seemed to indicate that returning
an error was preferable to silently ignoring the "udp"/"mntudp"
option.
This problem was discovered while investigating a problem reported
by pjd@ via email.
MFC after: 2 weeks
entries on one client when a directory was renamed on another client. The
root cause for the stale entry being trusted is that each per-vnode nfsnode
structure has a single 'n_ctime' timestamp used to validate positive name
cache entries. However, if there are multiple entries for a single vnode,
they all share a single timestamp. To fix this, extend the name cache
to allow filesystems to optionally store a timestamp value in each name
cache entry. The NFS clients now fetch the timestamp associated with
each name cache entry and use that to validate cache hits instead of the
timestamps previously stored in the nfsnode. Another part of the fix is
that the NFS clients now use timestamps from the post-op attributes of
RPCs when adding name cache entries rather than pulling the timestamps out
of the file's attribute cache. The latter is subject to races with other
lookups updating the attribute cache concurrently. Some more details:
- Add a variant of nfsm_postop_attr() to the old NFS client that can return
a vattr structure with a copy of the post-op attributes.
- Handle lookups of "." as a special case in the NFS clients since the name
cache does not store name cache entries for ".", so we cannot get a
useful timestamp. It didn't really make much sense to recheck the
attributes on the the directory to validate the namecache hit for "."
anyway.
- ABI compat shims for the name cache routines are present in this commit
so that it is safe to MFC.
MFC after: 2 weeks
get a reply of EEXIST from an NFS server when a Mkdir RPC was retried,
for an NFS over UDP mount.
Upon investigation, it was found that the client was retransmitting
the Mkdir RPC request over UDP, but with a different xid. As such,
the retransmitted message would miss the Duplicate Request Cache
in the server, causing it to reply EEXIST. The kernel client side
UDP rpc code has two timers. The first one causes a retransmit using
the same xid and socket and was set to a fixed value of 3seconds.
(The default can be overridden via CLSET_RETRY_TIMEOUT.)
The second one creates a new socket and xid and should be larger
than the first. However, both NFS clients were setting the second
timer to nm_timeo ("timeout=<value>" mount argument), which defaulted to
1second, so the first timer would never time out.
This patch fixes both NFS clients so that they set the first timer
using nm_timeo and makes the second timer larger than the first one.
Reported by: jwd
Tested by: jwd
Reviewed by: jhb
MFC after: 2 weeks
twice if the server bogusly returns an error with the NFSERR_RETERR
bit (bit 31) set. No actual NFS error has this bit set, but it seems
that amd will sometimes do this. This patch makes sure the NFSERR_RETERR
bit is cleared to avoid a crash.
PR: kern/153847
MFC after: 2 weeks
Allow the NFS client to use a max file size larger than 1TB for v3 mounts.
It now allows files up to OFF_MAX subject to whatever limit the server
advertises.
Reviewed by: rmacklem
Approved by: re (kib)
MFC after: 1 week
This was reported to the mailing list freebsd-net@freebsd.org
on July 21, 2011 under the subject "LOR with nfsclient sillyrename".
The LOR occurred when nfs_inactive() called vrele(sp->s_dvp)
while holding the vnode lock on the file in s_dvp. This patch
modifies the client so that it performs the vrele(sp->s_dvp)
as a separate task to avoid the LOR. This fix was discussed
with jhb@ and kib@, who both proposed variations of it.
Tested by: pho, jlott at averesystems.com
Submitted by: jhb (earlier version)
Reviewed by: kib
Approved by: re (kib)
MFC after: 2 weeks
the NFS subsystems use five of the rpcsec_gss/kgssapi entry points,
but since it was not obvious which others might be useful, all
nineteen were included. Basically the nineteen entry points are
set in a structure called rpc_gss_entries and inline functions
defined in sys/rpc/rpcsec_gss.h check for the entry points being
non-NULL and then call them. A default value is returned otherwise.
Requested by rwatson.
Reviewed by: jhb
MFC after: 2 weeks
VM_PAGER_AGAIN to VM_PAGER_ERROR for the uwritten pages. Return
VM_PAGER_AGAIN for the partially written page. Always forward at least
one page in the loop of vm_object_page_clean().
VM_PAGER_ERROR causes the page reactivation and does not clear the
page dirty state, so the write is not lost.
The change fixes an infinite loop in vm_object_page_clean() when the
filesystem returns permanent errors for some page writes.
Reported and tested by: gavin
Reviewed by: alc, rmacklem
MFC after: 1 week
in the old NFS client so that a forced dismount doesn't
get stuck in the VFS_SYNC() call that happens before
VFS_UNMOUNT() in dounmount(). Analagous to r222329 for the new NFS client.
An additional change is needed before forced dismounts will work.
PR: kern/157365
MFC after: 2 weeks
to both NFS clients. This avoids the crash reported by
Sergey Kandaurov (pluknet@gmail.com) to the freebsd-fs@
list with subject "[old nfsclient] different nmount()
args passed from mount vs mount_nfs" dated May 17, 2011.
Tested by: pluknet at gmail.com (old nfs client)
MFC after: 2 weeks
checking at open time. It may improve performance for read-only
NFS mounts. Use deliberately.
MFC after: 1 week
Reviewed by: rmacklem, jhb (earlier version)
NFS client (which I guess is no longer experimental). The fstype "newnfs"
is now "nfs" and the regular/old NFS client is now fstype "oldnfs".
Although mounts via fstype "nfs" will usually work without userland
changes, an updated mount_nfs(8) binary is needed for kernels built with
"options NFSCL" but not "options NFSCLIENT". Updated mount_nfs(8) and
mount(8) binaries are needed to do mounts for fstype "oldnfs".
The GENERIC kernel configs have been changed to use options
NFSCL and NFSD (the new client and server) instead of NFSCLIENT and NFSSERVER.
For kernels being used on diskless NFS root systems, "options NFSCL"
must be in the kernel config.
Discussed on freebsd-fs@.
when building kernels that don't have "options NFS_ROOT"
specified. I plan on moving the functions that use these
data structures into the shared code in sys/nfs/nfs_diskless.c
in a future commit. At that time, these definitions will no
longer be needed in nfs_vfsops.c and nfs_clvfsops.c.
MFC after: 2 weeks
set the f_flags field of "struct statfs". This had the interesting
effect of making the NFSv4 mounts "disappear" after r221014,
since NFSMNT_NFSV4 and MNT_IGNORE became the same bit.
Move the files used for a diskless NFS root from sys/nfsclient
to sys/nfs in preparation for them to be used by both NFS
clients. Also, move the declaration of the three global data
structures from sys/nfsclient/nfs_vfsops.c to sys/nfs/nfs_diskless.c
so that they are defined when either client uses them.
Reviewed by: jhb
MFC after: 2 weeks
"struct nfs_args" as the regular NFS client. This is needed
so that the old mount(2) syscall will work and it makes
sharing of the diskless NFS root code easier. Eary in the
porting exercise I introduced a new revision of nfs_args, but
didn't actually need it, thanks to nmount(2). I re-introduced the
NFSMNT_KERB flag, since it does essentially the same thing and
the old one would not have been used because it never worked.
I also added a few new NFSMNT_xxx flags to sys/nfsclient/nfs_args.h
that are used by the experimental NFS client.
MFC after: 2 weeks
PMC/SYSV/...).
No FreeBSD version bump, the userland application to query the features will
be committed last and can serve as an indication of the availablility if
needed.
Sponsored by: Google Summer of Code 2010
Submitted by: kibab
Reviewed by: arch@ (parts by rwatson, trasz, jhb)
X-MFC after: to be determined in last commit with code from this project
VNET socket push back:
try to minimize the number of places where we have to switch vnets
and narrow down the time we stay switched. Add assertions to the
socket code to catch possibly unset vnets as seen in r204147.
While this reduces the number of vnet recursion in some places like
NFS, POSIX local sockets and some netgraph, .. recursions are
impossible to fix.
The current expectations are documented at the beginning of
uipc_socket.c along with the other information there.
Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
Reviewed by: jhb
Tested by: zec
Tested by: Mikolaj Golub (to.my.trociny gmail.com)
MFC after: 2 weeks
and vop_reclaim() methods. They seems to be unused, and the reported
situation is normal for the forced unmount.
MFC after: 1 week
X-MFC-note: keep prtactive symbol in vfs_subr.c
by both clients. Since the NLM uses various fields of the
nfsmount structure, those fields were extracted and put in a
separate nfs_mountcommon structure stored in sys/nfs/nfs_mountcommon.h.
This structure also has a function pointer for a function that
extracts the required information from the mount point and nfs vnode
for that particular client, for information stored differently by the
clients.
Reviewed by: jhb
MFC after: 2 weeks
fixed the issues with file descriptor locks, but the same problems are
present for vnode lock/user map lock.
If the nfs_asyncio() cannot find the free nfsiod, schedule task to
create new nfsiod and return error. This causes fall back to the
synchronous i/o for nfs_strategy(), or does not start read at all in
the case of readahead. The caller that holds vnode and potentially
user map lock does not wait for kproc_create() to finish, preventing
the LORs.
The change effectively reverts r203072, because we never hand off the
request to newly created nfsiod thread anymore.
Reviewed by: jhb
Tested by: jhb, pluknet
MFC after: 3 weeks
vnode lock and several locks needed during fork, like fd lock.
Instead, schedule the task to be executed in the taskqueue context. We
still waiting for the fork to finish, but the context of the thread
executing the task does not make real LORs with our vnode lock.
Submitted by: pluknet at gmail com
Reviewed by: jhb
Tested by: pho
MFC after: 3 weeks
directories for purposes of validating name cache entries. This
closes races where two updates to a file or directory within the same
second could result in stale entries in the name cache. While here,
remove the 'n_expiry' field as it is no longer used.
Reviewed by: rmacklem
MFC after: 1 week
boot.nfsroot.nfshandlelen and set the diskless root fs to
use NFSv3 and this file handle length when it is set. If
this environment variable is not set, the diskless root fs
will use NFSv2 and the same defaults as before. This fixes
the problem where the diskless nfs root fs had to be on a
FreeBSD server for NFSv3 to work, because it did not know
the correct file handle length and assumed the size used
by FreeBSD. Until pxeboot and loader are replaced by ones
built from commits coming soon, boot.nfsroot.nfshandlelen
will not be set by them and the diskless root fs will use
NFSv2 unless the /etc/fstab entry has the "nfsv3" option
specified.
Tested by: danny at cs.huji.ac.il
MFC after: 2 weeks
LK_CANRECURSE after a lock is created. Use them to implement macros that
otherwise manipulated the flags directly. Assert that the associated
lockmgr lock is exclusively locked by the current thread when manipulating
these flags to ensure the flag updates are safe. This last change required
some minor shuffling in a few filesystems to exclusively lock a brand new
vnode slightly earlier.
Reviewed by: kib
MFC after: 3 days
module that can be used by both the regular and experimental nfs
clients. This fixes the problem reported by jh@ where /dev/nfslock
would be registered twice when both nfs clients were used.
I also defined the size of the lm_fh field to be the correct value,
as it should be the maximum size of an NFSv3 file handle.
Reviewed by: jh
MFC after: 2 weeks
to avoid sending multiple ACCESS/GETATTR RPCs during a single open()
between VOP_LOOKUP() and VOP_OPEN(). Now we always send the RPC in
VOP_LOOKUP() and not VOP_OPEN() in the cases that multiple RPCs could be
sent.
MFC after: 2 weeks
name cache up into nfs_lookup() instead of nfs_open(). Continue this
trend by flushing the attribute cache for leaf nodes in nfs_lookup() during
an open() if we do a LOOKUP RPC. For NFSv3 this should generally be a NOP
as the attributes are flushed before fetching the post-op attributes from
the LOOKUP RPC which most (all?) NFSv3 servers provide, so the post-op
attributes should populate the cache.
Now all NFS open() calls will always clear the cached attributes during the
nfs_lookup() prior to nfs_open() in the !NMODIFIED case to provide CTOC.
As a result, we can remove the conditional flushing of the attribute
cache from nfs_open().
Reviewed by: rmacklem, bde
MFC after: 2 weeks
DIAGNOSTIC and #ifndef DIAGNOSTIC for debug assertions, prefer
KASSERT(). Also change one #ifdef DIAGNOSTIC in the new nfs server.
Submitted by: Mikolaj Golub <to.my.trociny gmail com>
MFC after: 2 weeks
file via NFS. Specifically, to satisfy close-to-open-consistency, the NFS
client always performs at least one RPC on a file during an open(2) to see
if the file has changed. Normally this RPC is an ACCESS or GETATTR RPC
that is forced by flushing a file's attribute cache during nfs_open() and
then requesting new attributes. However, if the file is noticed to be
stale during nfs_open(), the only recourse is to fail the open(2) call
with ESTALE. On the other hand, if the ACCESS or GETATTR RPC is sent
during nfs_lookup(), then the NFS client can fall back to a LOOKUP RPC to
obtain the new file handle in the case that a file has been replaced.
This change causes the NFS client to flush the attribute cache during
nfs_lookup() when validating a name cache hit if the attributes fetched
during nfs_lookup() can be reused in nfs_open(). This allows the client
to open a replaced file via the new file handle the first time that it
notices a replaced file rather than failing with ESTALE in some cases.
Reviewed by: rmacklem, bde
Reviewed by: mohans (older version)
MFC after: 1 week
