memory mapped pages being written back on an NFS mount.
Since any thread can call VOP_PUTPAGES() to write back a
dirty page, the credentials of that thread may not have
write access to the file on an NFS server. (Often the uid
is 0, which may be mapped to "nobody" in the NFS server.)
Although there is no completely correct fix for this
(NFS servers check access on every write RPC instead of at
open/mmap time), this patch avoids the common cases by
holding onto a credential that recently opened the file
for writing and uses that credential for the write RPCs
being done by VOP_PUTPAGES() for both NFS clients.
Tested by: Joel Ray Holveck (joelh at juniper.net)
PR: kern/165923
Reviewed by: kib
MFC after: 2 weeks
The primary changes are that the user of the interface no longer
needs to manage the mount-mutex locking and that the vnode that
is returned has its mutex locked (thus avoiding the need to check
to see if its is DOOMED or other possible end of life senarios).
To minimize compatibility issues for third-party developers, the
old MNT_VNODE_FOREACH interface will remain available so that this
change can be MFC'ed to 9. Following the MFC to 9, MNT_VNODE_FOREACH
will be removed in head.
The reason for this update is to prepare for the addition of the
MNT_VNODE_FOREACH_ACTIVE interface that will loop over just the
active vnodes associated with a mount point (typically less than
1% of the vnodes associated with the mount point).
Reviewed by: kib
Tested by: Peter Holm
MFC after: 2 weeks
significantly. Upon investigation this was caused by name cache
misses for lookups of "..". For name cache entries for non-".."
directories, the cache entry serves double duty. It maps both the
named directory plus ".." for the parent of the directory. As such,
two ctime values (one for each of the directory and its parent) need
to be saved in the name cache entry.
This patch adds an entry for ctime of the parent directory to the
name cache. It also adds an additional uma zone for large entries
with this time value, in order to minimize memory wastage.
As well, it fixes a couple of cases where the mtime of the parent
directory was being saved instead of ctime for positive name cache
entries. With this patch, Lookup RPC counts return to values similar
to pre-r230394 kernels.
Reported by: bde
Discussed with: kib
Reviewed by: jhb
MFC after: 2 weeks
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.
Discussed with: bde, das (previous versions)
MFC after: 1 month
mnt_noasync counter to temporary remove MNTK_ASYNC mount option, which
is needed to guarantee a synchronous completion of the initiated i/o
before syscall or VOP return. Global removal of MNTK_ASYNC option is
harmful because not only i/o started from corresponding thread becomes
synchronous, but all i/o is synchronous on the filesystem which is
initiated during sync(2) or syncer activity.
Instead of removing MNTK_ASYNC from mnt_kern_flag, provide a local
thread flag to disable async i/o for current thread only. Use the
opportunity to move DOINGASYNC() macro into sys/vnode.h and
consistently use it through places which tested for MNTK_ASYNC.
Some testing demonstrated 60-70% improvements in run time for the
metadata-intensive operations on async-mounted UFS volumes, but still
with great deviation due to other reasons.
Reviewed by: mckusick
Tested by: scottl
MFC after: 2 weeks
the original IPv4 implementation from r178888:
- Use RT_DEFAULT_FIB in the IPv4 implementation where noticed.
- Use rt*fib() KPI with explicit RT_DEFAULT_FIB where applicable in
the NFS code.
- Use the new in6_rt* KPI in TCP, gif(4), and the IPv6 network stack
where applicable.
- Split in6_rtqtimo() and in6_mtutimo() as done in IPv4 and equally
prevent multiple initializations of callouts in in6_inithead().
- Use wrapper functions where needed to preserve the current KPI to
ease MFCs. Use BURN_BRIDGES to indicate expected future cleanup.
- Fix (related) comments (both technical or style).
- Convert to rtinit() where applicable and only use custom loops where
currently not possible otherwise.
- Multicast group, most neighbor discovery address actions and faith(4)
are locked to the default FIB. Individual IPv6 addresses will only
appear in the default FIB, however redirect information and prefixes
of connected subnets are automatically propagated to all FIBs by
default (mimicking IPv4 behavior as closely as possible).
Sponsored by: Cisco Systems, Inc.
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
