Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
大约 1 年 前同步成功

通知 158
Star 36
Fork 7
cloud-kernel
cloud-kernel

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 10 10月, 2007 4 次提交
    • C
      NFS: Eliminate nfs_renew_times() · 77a55a1f
      由 Chuck Lever 提交于 
      The nfs_renew_times() function plants the current time in jiffies in
dentry->d_time.  But a call to nfs_renew_times() is always followed by
another call that overwrites dentry->d_time.  Get rid of the
nfs_renew_times() calls.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      77a55a1f
    • C
      NFS: Don't call nfs_renew_times() in nfs_dentry_iput() · 92f6c178
      由 Chuck Lever 提交于 
      Negative dentries need to be reverified after an asynchronous unlink.

Quoth Trond:

"Unfortunately I don't think that we can avoid revalidating the
resulting negative dentry since the UNLINK call is asynchronous,
and so the new verifier on the directory will only be known a
posteriori."
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      92f6c178
    • F
      Re: [NFS] [PATCH] Attribute timeout handling and wrapping u32 jiffies · c7e15961
      由 Fabio Olive Leite 提交于 
      I would like to discuss the idea that the current checks for attribute
timeout using time_after are inadequate for 32bit architectures, since
time_after works correctly only when the two timestamps being compared
are within 2^31 jiffies of each other. The signed overflow caused by
comparing values more than 2^31 jiffies apart will flip the result,
causing incorrect assumptions of validity.

2^31 jiffies is a fairly large period of time (~25 days) when compared
to the lifetime of most kernel data structures, but for long lived NFS
mounts that can sit idle for months (think that for some reason autofs
cannot be used), it is easy to compare inode attribute timestamps with
very disparate or even bogus values (as in when jiffies have wrapped
many times, where the comparison doesn't even make sense).

Currently the code tests for attribute timeout by simply adding the
desired amount of jiffies to the stored timestamp and comparing that
with the current timestamp of obtained attribute data with time_after.
This is incorrect, as it returns true for the desired timeout period
and another full 2^31 range of jiffies.

In testing with artificial jumps (several small jumps, not one big
crank) of the jiffies I was able to reproduce a problem found in a
server with very long lived NFS mounts, where attributes would not be
refreshed even after touching files and directories in the server:

Initial uptime:
03:42:01 up 6 min, 0 users, load average: 0.01, 0.12, 0.07

NFS volume is mounted and time is advanced:
03:38:09 up 25 days, 2 min, 0 users, load average: 1.22, 1.05, 1.08

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Dec 17 03:38 /local/A/foo/bar
-rw-r--r--  1 root root 0 Nov 22 00:36 /nfs/A/foo/bar

# touch /local/A/foo/bar

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Dec 17 03:47 /local/A/foo/bar
-rw-r--r--  1 root root 0 Nov 22 00:36 /nfs/A/foo/bar

We can see the local mtime is updated, but the NFS mount still shows
the old value. The patch below makes it work:

Initial setup...
07:11:02 up 25 days, 1 min,  0 users,  load average: 0.15, 0.03, 0.04

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:11 /local/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:11 /nfs/A/foo/bar

# touch /local/A/foo/bar

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:14 /local/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:14 /nfs/A/foo/bar
Signed-off-by: NFabio Olive Leite <fleite@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      c7e15961
    • P
      64 bit ino support for NFS client · 4e769b93
      由 Peter Staubach 提交于 
      Hi.

Attached is a patch to modify the NFS client code to support
64 bit ino's, as appropriate for the system and the NFS
protocol version.

The code basically just expand the NFS interfaces for routines
which handle ino's from using ino_t to u64 and then uses the
fileid in the nfs_inode instead of i_ino in the inode.  The
code paths that were updated are in the getattr method and
the readdir methods.

This should be no real change on 64 bit platforms.  Since
the ino_t is an unsigned long, it would already be 64 bits
wide.

    Thanx...

           ps
Signed-off-by: NPeter Staubach <staubach@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      4e769b93
  3. 29 9月, 2007 1 次提交
  5. 20 7月, 2007 2 次提交
  7. 11 7月, 2007 4 次提交
  9. 22 5月, 2007 1 次提交
    • A
      Detach sched.h from mm.h · e8edc6e0
      由 Alexey Dobriyan 提交于 
      First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e8edc6e0
  11. 15 5月, 2007 1 次提交
    • T
      NFS: Fix some 'sparse' warnings... · 10afec90
      由 Trond Myklebust 提交于 
       - fs/nfs/dir.c:610:8: warning: symbol 'nfs_llseek_dir' was not declared.
   Should it be static?
 - fs/nfs/dir.c:636:5: warning: symbol 'nfs_fsync_dir' was not declared.
   Should it be static?
 - fs/nfs/write.c:925:19: warning: symbol 'req' shadows an earlier one
 - fs/nfs/write.c:61:6: warning: symbol 'nfs_commit_rcu_free' was not
   declared. Should it be static?
 - fs/nfs/nfs4proc.c:793:5: warning: symbol 'nfs4_recover_expired_lease'
   was not declared. Should it be static?
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      10afec90
  13. 10 5月, 2007 3 次提交
  15. 08 5月, 2007 1 次提交
  17. 01 5月, 2007 2 次提交
    • N
      NFS: Fix directory caching problem - with test case and patch. · 83672d39
      由 Neil Brown 提交于 
      Try running this script in an NFS mounted directory (Client relatively
recent - 2.6.18 has the problem as does 2.6.20).

------------------------------------------------------
#!/bin/bash
#
# This script will produce the following errormessage from tar:
#
#   tar: newdir/innerdir/innerfile: file changed as we read it

# create dirs
rm -rf nfstest
mkdir -p nfstest/dir/innerdir

# create files (should not be empty)
echo "Hello World!" >nfstest/dir/file
echo "Hello World!" >nfstest/dir/innerdir/innerfile

# problem only happens if we sleep before chmod
sleep 1

# change file modes
chmod -R a+r nfstest

# rename dir
mv nfstest/dir nfstest/newdir

# tar it
tar -cf nfstest/nfstest.tar -C nfstest newdir

# restore old dir name
mv nfstest/newdir nfstest/dir
--------------------------------------------------------

What happens:

The 'chmod -R' does a readdir_plus in each directory and the results
get cached in the page cache.  It then updates the ctime on each file
by one second.  When this happens, the post-op attributes are used to
update the ctime stored on the client to match the value in the kernel.

The 'mv' calls shrink_dcache_parent on the directory tree which
flushes all the dentries (so a new lookup will be required) but
doesn't flush the inodes or pagecache.

The 'tar' does a readdir on each directory, but (in the case of
'innerdir' at least) satisfies it from the pagecache and uses the
READDIRPLUS data to update all the inodes.  In the case of
'innerdir/innerfile', the ctime is out of date.

'tar' then calls 'lstat' on innerdir/innerfile getting an old ctime.
It then opens the file (triggering a GETATTR), reads the content, and
then calls fstat to see if anything has changed.  It finds that ctime
has changed and so complains.

The problem seems to be that the cache readdirplus info is kept around
for too long.

My patch below discards pagecache data for directories when
dentry_iput is called on them.  This effectively removes the symptom
which convinces me that I correctly understand the problem.  However
I'm not convinced that is a proper solution, as there could easily be
other races that trigger the same problem without being affected by
this 'fix'.

One possibility would be to require that readdirplus pagecache data be
only used *once* to instantiate an inode.  Somehow it should then be
invalidated so that if the dentry subsequently disappears, it will
cause a new request to the server to fill in the stat data.

Another possibility is to compare the cache_change_attribute on the
inode with something similar for the readdirplus info and reject the
info from readdirplus if it is too old.

I haven't tried to implement these and would value other opinions
before I do.

Thanks,
NeilBrown
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      83672d39
    • N
      NFS: Set meaningful value for fattr->time_start in readdirplus results. · 1f4eab7e
      由 Neil Brown 提交于 
      Don't use uninitialsed value for fattr->time_start in readdirplus results.

The 'fattr' structure filled in by nfs3_decode_direct does not get a
value for ->time_start set.
Thus if an entry is for an inode that we already have in cache,
when nfs_readdir_lookup calls nfs_fhget, it will call nfs_refresh_inode
and may update the inode with out-of-date information.

Directories are read a page at a time, so each page could have a
different timestamp that "should" be used to set the time_start for
the fattr for info in that page.  However storing the timestamp per
page is awkward.  (We could stick in the first 4 bytes and only read 4092
bytes, but that is a bigger code change than I am interested it).

This patch ignores the readdir_plus attributes if a readdir finds the
information already in cache, and otherwise sets ->time_start to the time
the readdir request was sent to the server.

It might be nice to store - in the directory inode - the time stamp for
the earliest readdir request that is still in the page cache, so that we
don't ignore attribute data that we don't have to.  This patch doesn't do
that.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      1f4eab7e
  19. 15 4月, 2007 1 次提交
  21. 13 2月, 2007 1 次提交
  23. 04 2月, 2007 4 次提交
  25. 25 1月, 2007 1 次提交
  27. 09 12月, 2006 1 次提交
  29. 22 10月, 2006 2 次提交
  31. 21 10月, 2006 3 次提交
  33. 01 10月, 2006 2 次提交
  35. 25 9月, 2006 1 次提交
  37. 23 9月, 2006 5 次提交