operation on POSIX shared memory objects and tmpfs. Previously, neither of
these modules correctly handled the case in which the new size of the object
or file was not a multiple of the page size. Specifically, they did not
handle partial page truncation of data stored on swap. As a result, stale
data might later be returned to an application.
Interestingly, a data inconsistency was less likely to occur under tmpfs
than POSIX shared memory objects. The reason being that a different mistake
by the tmpfs truncation operation helped avoid a data inconsistency. If the
data was still resident in memory in a PG_CACHED page, then the tmpfs
truncation operation would reactivate that page, zero the truncated portion,
and leave the page pinned in memory. More precisely, the benevolent error
was that the truncation operation didn't add the reactivated page to any of
the paging queues, effectively pinning the page. This page would remain
pinned until the file was destroyed or the page was read or written. With
this change, the page is now added to the inactive queue.
Discussed with: jhb
Reviewed by: kib (an earlier version)
MFC after: 3 weeks
The effect of this was, for clients mounted via inet6 addresses,
that the DRC cache would never have a hit in the server. It also
broke NFSv4 callbacks when an inet6 address was the only one available
in the client. This patch fixes the above, plus deletes opt_inet6.h
from a couple of files it is not needed for.
MFC after: 2 weeks
consequence sbuf_len() will return -1 for buffers which had the error
status set prior to sbuf_finish() call. This causes a problem in
pfs_read() which purposely uses a fixed size sbuf to discard bytes which
are not needed to fulfill the read request.
Work around the problem by using the full buffer length when
sbuf_finish() indicates an overflow. An overflowed sbuf with fixed size
is always full.
PR: kern/163076
Approved by: des
MFC after: 2 weeks
Several callers of null_nodeget() did the cleanup itself, but several
missed it, most prominent being null_bypass(). Remove the cleanup from
the callers, now null_nodeget() handles lowervp free itself.
Reported and tested by: pho
MFC after: 1 week
tmpfs_nocacheread(). It is both unnecessary and a pessimization. It
results in either the page being zeroed twice or zeroed first and then
overwritten by an I/O operation.
MFC after: 3 weeks
It seems strchr() and strrchr() are used more often than index() and
rindex(). Therefore, simply migrate all kernel code to use it.
For the XFS code, remove an empty line to make the code identical to
the code in the Linux kernel.
While there, remove a useless check from the code. memcchr() always
returns characters unequal to 0xff in this case, so inosused[i] ^ 0xff
can never be equal to zero. Also, the fact that memcchr() returns a
pointer instead of the number of bytes until the end, makes conversion
to an offset far more easy.
jhb@ spotted that nfscl_getstateid() might modify credentials when
called from nfsrpc_read() for the case where p != NULL, whereas
nfsrpc_read() only did a crdup() to get new credentials for p == NULL.
This bug was introduced by r195510, since pre-r195510 nfscl_getstateid()
only modified credentials for the p == NULL case. This patch modifies
nfsrpc_read()/nfsrpc_write() so that they do crdup() for the p != NULL case.
It is conceivable that this bug caused the crash reported by glebius@, but
that will not be determined for some time, since the crash occurred after
about 1month of operation.
Tested by: glebius
Reviewed by: jhb
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
Fix a comment from the previous commit.
Use M_ZERO instead of bzero() in ext2_vfsops.c
Add include guards from PR.
PR: 162564
Approved by: jhb (mentor)
MFC after: 2 weeks
The feature has been standard for a while in UFS as a means to reduce
fragmentation, therefore maintaining consistent performance with
filesystem aging. This is also very similar to what ext4 calls
"delayed allocation".
In his 2010 GSoC, Zheng Liu ported and benchmarked the missing
FANCY_REALLOC code to find more consistent performance improvements than
with the preallocation approach.
PR: 159233
Author: Zheng Liu <gnehzuil AT SPAMFREE gmail DOT com>
Sponsored by: Google Inc.
Approved by: jhb (mentor)
MFC after: 2 weeks
This removes the obfuscations mentioned in ext2_readwrite and
places the clustering funtion in a location similar to other
UFS-based implementations.
No performance or functional changeses are expected from
this move.
PR: kern/159232
Suggested by: bde
Approved by: jhb (mentor)
MFC after: 2 weeks
of a devfs file descriptor in devfs_close_f(). The passed in td argument
may be NULL if the close was invoked by garbage collection of open
file descriptors in pending control messages in the socket buffer of a
UNIX domain socket after it was closed.
PR: kern/151758
Submitted by: Andrey Shidakov andrey shidakov ru
Submitted by: Ruben van Staveren ruben verweg com
Reviewed by: kib
MFC after: 2 weeks
difference between fi_wgen and f_seqcount, so the change is purely
cosmetic, but it makes the code easier to understand.
Submitted by: gianni
MFC after: 2 weeks
check for a UTF-8 compliant file name. Enabling this sysctl results in
an NFSv4 server that is non-RFC3530 compliant, therefore it is not enabled
by default. However, enabling this sysctl results in NFSv3 compatible
behaviour and fixes the problem reported by "dan at sunsaturn.com"
to freebsd-current@ on Nov. 14, 2011 under the subject "NFSV4 readlink_stat".
Tested by: dan at sunsaturn.com
Reviewed by: zack
MFC after: 2 weeks
of the same lock_owner4 string. As such, the handling of cleanup
of lock_owners could be simplified. This simplification permitted
the client to do a ReleaseLockOwner operation when the process that
the lock_owner4 string represents, has exited. This permits the
server to release any storage related to the lock_owner4 string
before the associated open is closed. Without this change, it
is possible to exhaust a server's storage when a long running
process opens a file and then many child processes do locking
on the file, because the open doesn't get closed. A similar patch
was applied to the Linux NFSv4 client recently so that it wouldn't
exhaust a server's storage.
Reviewed by: zack
MFC after: 2 weeks
NFS server and reuse it for writes as well to allow writes to the backing
store to be clustered.
- Use a prime number for the size of the heuristic table (1017 is not
prime).
- Move the logic to locate a heuristic entry from the table and compute
the sequential count out of VOP_READ() and into a separate routine.
- Use the logic from sequential_heuristic() in vfs_vnops.c to update the
seqcount when a sequential access is performed rather than just
increasing seqcount by 1. This lets the clustering count ramp up
faster.
- Allow for some reordering of RPCs and if it is detected leave the current
seqcount as-is rather than dropping back to a seqcount of 1. Also,
when out of order access is encountered, cut seqcount in half rather than
dropping it all the way back to 1 to further aid with reordering.
- Fix the new NFS server to properly update the next offset after a
successful VOP_READ() so that the readahead actually works.
Some of these changes came from an earlier patch by Bjorn Gronwall that was
forwarded to me by bde@.
Discussed with: bde, rmacklem, fs@
Submitted by: Bjorn Gronwall (1, 4)
MFC after: 2 weeks
vnode locking for read, readdir, readlink, getattr and access.
It is hoped that this will improve server performance for these
operations, since they will no longer be serialized for a given
file/vnode.
- Don't deduct wired pages from total usable counts because it does not
make any sense. To make things worse, on systems where swap size is
smaller than physical memory and use a lot of wired pages (e.g. ZFS),
tmpfs can suddenly have free space of 0 because of this;
- Count cached pages as available; [1]
- Don't count inactive pages as available, technically we could but that
might be too aggressive; [1]
[1] Suggested by kib@
MFC after: 1 week
client. This does not change the client's behaviour, but prepares
the code so that nfsrpc_rellockown() can be called elsewhere in a
future commit.
MFC after: 2 weeks
head nfsc_defunctlockowner. This patch simply removes the code that
loops through this always empty list, since the code no longer does
anything useful. It should not have any effect on the client's
behaviour.
MFC after: 2 weeks
nullfs. The problem is that resulting vnode is only required to be
held on return from the successfull call to vop, instead of being
referenced.
Nullfs VOP_INACTIVE() method reclaims the vnode, which in combination
with the VOP_VPTOCNP() interface means that the directory vnode
returned from VOP_VPTOCNP() is reclaimed in advance, causing
vn_fullpath() to error with EBADF or like.
Change the interface for VOP_VPTOCNP(), now the dvp must be
referenced. Convert all in-tree implementations of VOP_VPTOCNP(),
which is trivial, because vhold(9) and vref(9) are similar in the
locking prerequisites. Out-of-tree fs implementation of VOP_VPTOCNP(),
if any, should have no trouble with the fix.
Tested by: pho
Reviewed by: mckusick
MFC after: 3 weeks (subject of re approval)
for regular files. Since other file types don't write into the
buffer cache, calling ncl_flush() is almost a no-op. However, it does
clear the NMODIFIED flag and this shouldn't be done by nfs_fsync() for
directories.
MFC after: 2 weeks
before the nfs_decode_args() call in the new NFS client, so
that a specfied command line value won't be overwritten.
Also, modify the calculation for small values of desiredvnodes
to avoid an unusually large value or a divide by zero crash.
It seems that the default value for nm_wcommitsize is very
conservative and may need to change at some time.
PR: kern/159351
Submitted by: onwahe at gmail.com (earlier version)
Reviewed by: jhb
MFC after: 2 weeks
