Commit graph

57 commits

Author SHA1 Message Date
Trond Myklebust
cd9ae2b6a7 [PATCH] NFS: Deal with failure of invalidate_inode_pages2()
If invalidate_inode_pages2() fails, then it should in principle just be
because the current process was signalled.  In that case, we just want to
ensure that the inode's page cache remains marked as invalid.

Also add a helper to allow the O_DIRECT code to simply mark the page cache as
invalid once it is finished writing, instead of calling
invalidate_inode_pages2() itself.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:39 -07:00
Trond Myklebust
eda3cef8dd [PATCH] NFS: Fix error handling in nfs_direct_write_result()
If the RPC call tanked, we should not be checking the return value
of data->res.verf->committed, since it is unlikely to even be
initialised.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-20 10:26:38 -07:00
Badari Pulavarty
027445c372 [PATCH] Vectorize aio_read/aio_write fileop methods
This patch vectorizes aio_read() and aio_write() methods to prepare for
collapsing all aio & vectored operations into one interface - which is
aio_read()/aio_write().

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Michael Holzheu <HOLZHEU@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01 00:39:28 -07:00
Alexey Dobriyan
1a1d92c10d [PATCH] Really ignore kmem_cache_destroy return value
* Rougly half of callers already do it by not checking return value
* Code in drivers/acpi/osl.c does the following to be sure:

	(void)kmem_cache_destroy(cache);

* Those who check it printk something, however, slab_error already printed
  the name of failed cache.
* XFS BUGs on failed kmem_cache_destroy which is not the decision
  low-level filesystem driver should make. Converted to ignore.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Trond Myklebust
e9f7bee1df [PATCH] NFS: large non-page-aligned direct I/O clobbers memory
The logic in nfs_direct_read_schedule and nfs_direct_write_schedule can
allow data->npages to be one larger than rpages.  This causes a page
pointer to be written beyond the end of the pagevec in nfs_read_data (or
nfs_write_data).

Fix this by making nfs_(read|write)_alloc() calculate the size of the
pagevec array, and initialise data->npages.

Also get rid of the redundant argument to nfs_commit_alloc().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-08 10:22:51 -07:00
Trond Myklebust
026477c114 Merge branch 'master' of /home/trondmy/kernel/linux-2.6/ 2006-07-03 13:49:45 -04:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Trond Myklebust
607f31e80b Revert "Merge branch 'odirect'"
This reverts ccf01ef7aa commit.

No idea how git managed this one: when I asked it to merge the odirect
topic branch it actually generated a patch which reverted the change.

Reverting the 'merge' will once again reveal Chuck's recent NFS/O_DIRECT
work to the world.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-28 16:52:45 -04:00
David Brownell
266bee8869 [PATCH] fix static linking of NFS
Builds on ARM report link problems with common configurations like
statically linked NFS (for nfsroot).  The symptom is that __init
section code references __exit section code; that won't work since
the exit sections are discarded (since they can never be called).

The best fix for these particular cases would be an "__init_or_exit"
section annotation.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-27 14:07:19 -07:00
Trond Myklebust
ccf01ef7aa Merge branch 'odirect' 2006-06-25 06:27:31 -04:00
Chuck Lever
82b145c5a5 NFS: alloc nfs_read/write_data as direct I/O is scheduled
Re-arrange the logic in the NFS direct I/O path so that nfs_read/write_data
structs are allocated just before they are scheduled, rather than
allocating them all at once before we start scheduling requests.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:39 -04:00
Chuck Lever
06cf6f2ed0 NFS: Eliminate nfs_get_user_pages()
Neil Brown observed that the kmalloc() in nfs_get_user_pages() is more
likely to fail if the I/O is large enough to require the allocation of more
than a single page to keep track of all the pinned pages in the user's
buffer.

Instead of tracking one large page array per dreq/iocb, track pages per
nfs_read/write_data, just like the cached I/O path does.  An array for
pages is already allocated for us by nfs_readdata_alloc() (and the write
and commit equivalents).

This is also required for adding support for vectored I/O to the NFS direct
I/O path.

The original reason to pin the user buffer and allocate all the NFS data
structures before trying to schedule I/O was to ensure all needed resources
are allocated on the client before starting to send requests.  This reduces
the chance that resource exhaustion on the client will cause a short read
or write.

On the other hand, for an application making very large application I/O
requests, this means that it will be nearly impossible for the application
to make forward progress on a resource-limited client.

Thus, moving the buffer pinning functionality into the I/O scheduling
loops should be good for scalability.  The next patch will do the same for
NFS data structure allocation.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:39 -04:00
Chuck Lever
9c93ab7dff NFS: refactor nfs_direct_free_user_pages
Clean-up and fix a minor bug: the logic was dirtying page cache pages on
both read and write operations.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:39 -04:00
Chuck Lever
51a7bc6cae NFS: remove user_addr, user_count, and pos from nfs_direct_req
Make the user_addr, user_count, and pos parameters explicit to the
scheduler routines, and remove the fields from nfs_direct_req.  The
iovec API will be passing in a series of these, not just one set.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:39 -04:00
Chuck Lever
fedb595c66 NFS: "open code" the NFS direct write rescheduler
An NFSv3/v4 client must reschedule on-the-wire writes if the writes are
UNSTABLE, and the server reboots before the client can complete a
subsequent COMMIT request.

To support direct asynchronous scatter-gather writes, the write
rescheduler in fs/nfs/direct.c must not depend on the I/O parameters
in the controlling nfs_direct_req structure.  iovecs can be somewhat
arbitrarily complex, so there could be an unbounded amount of information
to save for a rarely encountered requirement.

Refactor the direct write rescheduler so it uses information from each
nfs_write_data structure to reschedule writes, instead of caching that
information in the controlling nfs_direct_req structure.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:38 -04:00
Chuck Lever
b1c5921c5b NFS: Separate functions for counting outstanding NFS direct I/Os
Factor out the logic that increments and decrements the outstanding I/O
count.  This will be a commonly used bit of code in upcoming patches.
Also make this an atomic_t again, since it will be very often manipulated
outside dreq->spin lock.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-24 13:11:38 -04:00
David Howells
f7b422b17e NFS: Split fs/nfs/inode.c
As fs/nfs/inode.c is rather large, heterogenous and unwieldy, the attached
patch splits it up into a number of files:

 (*) fs/nfs/inode.c

     Strictly inode specific functions.

 (*) fs/nfs/super.c

     Superblock management functions for NFS and NFS4, normal access, clones
     and referrals.  The NFS4 superblock functions _could_ move out into a
     separate conditionally compiled file, but it's probably not worth it as
     there're so many common bits.

 (*) fs/nfs/namespace.c

     Some namespace-specific functions have been moved here.

 (*) fs/nfs/nfs4namespace.c

     NFS4-specific namespace functions (this could be merged into the previous
     file).  This file is conditionally compiled.

 (*) fs/nfs/internal.h

     Inter-file declarations, plus a few simple utility functions moved from
     fs/nfs/inode.c.

     Additionally, all the in-.c-file externs have been moved here, and those
     files they were moved from now includes this file.

For the most part, the functions have not been changed, only some multiplexor
functions have changed significantly.

I've also:

 (*) Added some extra banner comments above some functions.

 (*) Rearranged the function order within the files to be more logical and
     better grouped (IMO), though someone may prefer a different order.

 (*) Reduced the number of #ifdefs in .c files.

 (*) Added missing __init and __exit directives.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-06-09 09:34:33 -04:00
Trond Myklebust
e99170ff3b NFS,SUNRPC: Fix compiler warnings if CONFIG_PROC_FS & CONFIG_SYSCTL are unset
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-04-19 12:43:47 -04:00
Linus Torvalds
53846a21c1 Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (103 commits)
  SUNRPC,RPCSEC_GSS: spkm3--fix config dependencies
  SUNRPC,RPCSEC_GSS: spkm3: import contexts using NID_cast5_cbc
  LOCKD: Make nlmsvc_traverse_shares return void
  LOCKD: nlmsvc_traverse_blocks return is unused
  SUNRPC,RPCSEC_GSS: fix krb5 sequence numbers.
  NFSv4: Dont list system.nfs4_acl for filesystems that don't support it.
  SUNRPC,RPCSEC_GSS: remove unnecessary kmalloc of a checksum
  SUNRPC: Ensure rpc_call_async() always calls tk_ops->rpc_release()
  SUNRPC: Fix memory barriers for req->rq_received
  NFS: Fix a race in nfs_sync_inode()
  NFS: Clean up nfs_flush_list()
  NFS: Fix a race with PG_private and nfs_release_page()
  NFSv4: Ensure the callback daemon flushes signals
  SUNRPC: Fix a 'Busy inodes' error in rpc_pipefs
  NFS, NLM: Allow blocking locks to respect signals
  NFS: Make nfs_fhget() return appropriate error values
  NFSv4: Fix an oops in nfs4_fill_super
  lockd: blocks should hold a reference to the nlm_file
  NFSv4: SETCLIENTID_CONFIRM should handle NFS4ERR_DELAY/NFS4ERR_RESOURCE
  NFSv4: Send the delegation stateid for SETATTR calls
  ...
2006-03-25 09:18:27 -08:00
Paul Jackson
fffb60f93c [PATCH] cpuset memory spread: slab cache format
Rewrap the overly long source code lines resulting from the previous
patch's addition of the slab cache flag SLAB_MEM_SPREAD.  This patch
contains only formatting changes, and no function change.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:23 -08:00
Paul Jackson
4b6a9316fa [PATCH] cpuset memory spread: slab cache filesystems
Mark file system inode and similar slab caches subject to SLAB_MEM_SPREAD
memory spreading.

If a slab cache is marked SLAB_MEM_SPREAD, then anytime that a task that's
in a cpuset with the 'memory_spread_slab' option enabled goes to allocate
from such a slab cache, the allocations are spread evenly over all the
memory nodes (task->mems_allowed) allowed to that task, instead of favoring
allocation on the node local to the current cpu.

The following inode and similar caches are marked SLAB_MEM_SPREAD:

    file                               cache
    ====                               =====
    fs/adfs/super.c                    adfs_inode_cache
    fs/affs/super.c                    affs_inode_cache
    fs/befs/linuxvfs.c                 befs_inode_cache
    fs/bfs/inode.c                     bfs_inode_cache
    fs/block_dev.c                     bdev_cache
    fs/cifs/cifsfs.c                   cifs_inode_cache
    fs/coda/inode.c                    coda_inode_cache
    fs/dquot.c                         dquot
    fs/efs/super.c                     efs_inode_cache
    fs/ext2/super.c                    ext2_inode_cache
    fs/ext2/xattr.c (fs/mbcache.c)     ext2_xattr
    fs/ext3/super.c                    ext3_inode_cache
    fs/ext3/xattr.c (fs/mbcache.c)     ext3_xattr
    fs/fat/cache.c                     fat_cache
    fs/fat/inode.c                     fat_inode_cache
    fs/freevxfs/vxfs_super.c           vxfs_inode
    fs/hpfs/super.c                    hpfs_inode_cache
    fs/isofs/inode.c                   isofs_inode_cache
    fs/jffs/inode-v23.c                jffs_fm
    fs/jffs2/super.c                   jffs2_i
    fs/jfs/super.c                     jfs_ip
    fs/minix/inode.c                   minix_inode_cache
    fs/ncpfs/inode.c                   ncp_inode_cache
    fs/nfs/direct.c                    nfs_direct_cache
    fs/nfs/inode.c                     nfs_inode_cache
    fs/ntfs/super.c                    ntfs_big_inode_cache_name
    fs/ntfs/super.c                    ntfs_inode_cache
    fs/ocfs2/dlm/dlmfs.c               dlmfs_inode_cache
    fs/ocfs2/super.c                   ocfs2_inode_cache
    fs/proc/inode.c                    proc_inode_cache
    fs/qnx4/inode.c                    qnx4_inode_cache
    fs/reiserfs/super.c                reiser_inode_cache
    fs/romfs/inode.c                   romfs_inode_cache
    fs/smbfs/inode.c                   smb_inode_cache
    fs/sysv/inode.c                    sysv_inode_cache
    fs/udf/super.c                     udf_inode_cache
    fs/ufs/super.c                     ufs_inode_cache
    net/socket.c                       sock_inode_cache
    net/sunrpc/rpc_pipe.c              rpc_inode_cache

The choice of which slab caches to so mark was quite simple.  I marked
those already marked SLAB_RECLAIM_ACCOUNT, except for fs/xfs, dentry_cache,
inode_cache, and buffer_head, which were marked in a previous patch.  Even
though SLAB_RECLAIM_ACCOUNT is for a different purpose, it marks the same
potentially large file system i/o related slab caches as we need for memory
spreading.

Given that the rule now becomes "wherever you would have used a
SLAB_RECLAIM_ACCOUNT slab cache flag before (usually the inode cache), use
the SLAB_MEM_SPREAD flag too", this should be easy enough to maintain.
Future file system writers will just copy one of the existing file system
slab cache setups and tend to get it right without thinking.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:23 -08:00
Trond Myklebust
d72b7a6b26 NFS: O_DIRECT needs to use a completion
Now that we have aio writes, it is possible for dreq->outstanding to be
zero, but for the I/O not to have completed. Convert struct nfs_direct_req
to use a completion to signal when the I/O is done.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:43 -05:00
Trond Myklebust
6b45d858ed NFS: Clean up nfs_get_user_pages
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:43 -05:00
Chuck Lever
606bbba06b NFS: fix compiler warnings on 64-bit platforms
Introduced by NFS aio+dio patches.

Test plan:
Compile kernel with CONFIG_NFS enabled on 64-bit hardware.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:42 -05:00
Trond Myklebust
5db3a7b2ca NFS: Debugging code for nfs_direct_(read|write)_schedule()
Make sure that we're doing our list accounting correctly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:37 -05:00
Trond Myklebust
a8881f5a5c NFS: O_DIRECT async IO may lose context
The struct nfs_direct_req currently keeps a pointer to the file descriptor
without referencing it. This may cause problems if the parent process is
killed.

The nfs_open_context should normally have all the information that we're
currently using the filp for, and unlike fput(), is safe to release from
an rpciod process context.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:36 -05:00
Trond Myklebust
fad6149041 nfs: Use UNSTABLE + COMMIT for NFS O_DIRECT writes
Currently NFS O_DIRECT writes use FILE_SYNC so that a COMMIT is not
necessary.  This simplifies the internal logic, but this could be a
difficult workload for some servers.

Instead, let's send UNSTABLE writes, and after they all complete, send a
COMMIT for the dirty range.  After the COMMIT returns successfully, then do
the wake_up or fire off aio_complete().

Test plan:
Async direct I/O tests against Solaris (or any server that requires
committed unstable writes).  Reboot server during test.

Based on an earlier patch by Chuck Lever <cel@netapp.com>

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:36 -05:00
Chuck Lever
a37ec012d7 NFS: fix data_update accounting in NFS direct I/O path
^C against "iozone -I" is hitting the assertion in nfs_clear_inode().

Test plan:
"iozone -i0 -I -a -c" against a slow server, then control C.  This should
not cause an oops.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:35 -05:00
Chuck Lever
15ce4a0c1c NFS: Replace atomic_t variables in nfs_direct_req with a single spin lock
Three atomic_t variables cause a lot of bus locking.  Because they are all
used in the same places in the code, just use a single spin lock.

Now that the atomic_t variables are gone, we can remove the request size
limitation since the code no longer depends on the limited width of atomic_t
on some platforms.

Test plan:
Compile with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.  Millions of fsx
operations, iozone, OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:34 -05:00
Chuck Lever
88467055f7 NFS: clean up comments and tab damage in direct.c
Clean up tab damage and comments.  Replace "file_offset" with more commonly
used "pos".

Test plan:
Compile with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:34 -05:00
Chuck Lever
9eafa8cc52 NFS: support EIOCBQUEUED return in direct write path
For async iocb's, the NFS direct write path now returns EIOCBQUEUED,
and calls aio_complete when all the requested writes are finished.  The
synchronous part of the NFS direct write path behaves exactly as it
was before.

Shared mapped NFS files will have some coherency difficulties when
accessed concurrently with aio+dio.  Will need to explore how this
is handled in the local file system case.

Test plan:
aio-stress with "-O". OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:33 -05:00
Chuck Lever
c89f2ee5f9 NFS: make iocb available everywhere in direct write path
Pass the iocb argument all the way down to the direct write request
scheduler, and make it available in nfs_direct_write_result.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.
Millions of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:33 -05:00
Chuck Lever
47989d7454 NFS: remove support for multi-segment iovs in the direct write path
Eliminate the persistent use of automatic storage in all parts of the
NFS client's direct write path to pave the way for introducing support
for aio against files opened with the O_DIRECT flag.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.
Millions of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:32 -05:00
Chuck Lever
462d5b3296 NFS: make direct write path generate write requests concurrently
Duplicate infrastructure from direct read path that will allow write
path to generate multiple write requests concurrently.  This will
enable us to add support for aio in this path.

Temporarily we will lose the ability to do UNSTABLE writes followed by
a COMMIT in the direct write path.  However, all applications I am
aware of that use NFS O_DIRECT currently write in relatively small
chunks, so this should not be inconvenient in any way.

Test plan:
Millions of fsx-odirect ops. OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:32 -05:00
Chuck Lever
63ab46abc7 NFS: create common routine for handling direct I/O completion
Factor out the common piece of completing an NFS direct I/O request.

Test plan:
Compile kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:31 -05:00
Chuck Lever
93619e5989 NFS: create common routine for allocating nfs_direct_req
Factor out a small common piece of the path that allocate nfs_direct_req
structures.

Test plan:
Compile kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:31 -05:00
Chuck Lever
bc0fb201b3 NFS: create common routine for waiting for direct I/O to complete
We're about to add asynchrony to the NFS direct write path.  Begin by
abstracting out the common pieces in the read path.

The first piece is nfs_direct_read_wait, which works the same whether the
process is waiting for a read or a write.

Test plan:
Compile kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:31 -05:00
Chuck Lever
487b83723e NFS: support EIOCBQUEUED return in direct read path
For async iocb's, the NFS direct read path should return EIOCBQUEUED and
call aio_complete when all the requested reads are finished.  The
synchronous part of the NFS direct read path behaves exactly as it was
before.

Test plan:
aio-stress with "-O".  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:30 -05:00
Chuck Lever
99514f8fdd NFS: make iocb available everywhere in direct read path
Pass the iocb argument all the way down to the direct read request
scheduler, and make it available in nfs_direct_read_result.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.
Millions of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:30 -05:00
Chuck Lever
0cdd80d07f NFS: remove support for multi-segment iovs in the direct read path
Eliminate the persistent use of automatic storage in all parts of the NFS
client's direct read path to pave the way for introducing support for aio
against files opened with the O_DIRECT flag.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.
Millions of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:29 -05:00
Chuck Lever
5dd602f206 NFS: use size_t type for holding rsize bytes in NFS O_DIRECT read path
size_t is used for holding byte counts, so use it for variables storing rsize.
Note that the write path will be updated as we add support for async
O_DIRECT writes.

Test plan:
Need to verify that existing comparisons against new size_t variables behave
correctly.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:29 -05:00
Chuck Lever
d4cc948ba9 NFS: update comments and function definitions in fs/nfs/direct.c
Update to latest coding style standards.  Remove block comments on
statically defined functions, and place function definitions all on
one line.

Test plan:
Compile kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:28 -05:00
Chuck Lever
b8a32e2b8b NFS: clean up NFS client's a_ops->direct_IO method
The NFS client's a_ops->direct_IO method, nfs_direct_IO, is required to
be present to allow NFS files to be opened with O_DIRECT, but is never
called because the NFS client shunts reads and writes to files opened
with O_DIRECT directly to its own routines.

Gut the nfs_direct_IO function.  This eliminates the only part of the
NFS client's direct I/O path that requires support for multi-segment
iovs, allowing further simplification in subsequent patches.

Test plan:
Compile the kernel with CONFIG_NFS and CONFIG_NFS_DIRECTIO enabled.  Millions
of fsx-odirect ops.  OraSim.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:28 -05:00
Trond Myklebust
ec06c096ed NFS: Cleanup of NFS read code
Same callback hierarchy inversion as for the NFS write calls. This patch is
not strictly speaking needed by the O_DIRECT code, but avoids confusing
differences between the asynchronous read and write code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:27 -05:00
Chuck Lever
91d5b47023 NFS: add I/O performance counters
Invoke the byte and event counter macros where we want to count bytes and
events.

Clean-up: fix a possible NULL dereference in nfs_lock, and simplify
nfs_file_open.

Test-plan:
fsx and iozone on UP and SMP systems, with and without pre-emption.  Watch
for memory overwrite bugs, and performance loss (significantly more CPU
required per op).

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:14 -05:00
Trond Myklebust
143f412eb4 [PATCH] NFS: Fix a potential panic in O_DIRECT
Based on an original patch by Mike O'Connor and Greg Banks of SGI.

Mike states:

A normal user can panic an NFS client and cause a local DoS with
'judicious'(?) use of O_DIRECT.  Any O_DIRECT write to an NFS file where the
user buffer starts with a valid mapped page and contains an unmapped page,
will crash in this way.  I haven't followed the code, but O_DIRECT reads with
similar user buffers will probably also crash albeit in different ways.

Details: when nfs_get_user_pages() calls get_user_pages(), it detects and
correctly handles get_user_pages() returning an error, which happens if the
first page covered by the user buffer's address range is unmapped.  However,
if the first page is mapped but some subsequent page isn't, get_user_pages()
will return a positive number which is less than the number of pages requested
(this behaviour is sort of analagous to a short write() call and appears to be
intentional).  nfs_get_user_pages() doesn't detect this and hands off the
array of pages (whose last few elements are random rubbish from the newly
allocated array memory) to it's caller, whence they go to
nfs_direct_write_seg(), which then totally ignores the nr_pages it's given,
and calculates its own idea of how many pages are in the array from the user
buffer length.  Needless to say, when it comes to transmit those uninitialised
page* pointers, we see a crash in the network stack.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-14 07:57:17 -08:00
Dirk Mueller
1935245655 NFSv3: fix sync_retry in direct i/o NFS
Only do a sync_retry if the memcmp failed.

 Signed-off-by: Dirk Mueller <dmueller@suse.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-02-01 12:52:25 -05:00
Trond Myklebust
566dd6064e NFS: Make directIO aware of compound pages...
...and avoid calling set_page_dirty on them

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:50 -05:00
Chuck Lever
40859d7ee6 NFS: support large reads and writes on the wire
Most NFS server implementations allow up to 64KB reads and writes on the
 wire.  The Solaris NFS server allows up to a megabyte, for instance.

 Now the Linux NFS client supports transfer sizes up to 1MB, too.  This will
 help reduce protocol and context switch overhead on read/write intensive NFS
 workloads, and support larger atomic read and write operations on servers
 that support them.

 Test-plan:
 Connectathon and iozone on mount point with wsize=rsize>32768 over TCP.
 Tests with NFS over UDP to verify the maximum RPC payload size cap.

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:49 -05:00
Chuck Lever
ce1a8e6796 NFS: use generic_write_checks() to sanity check direct writes
Replace ad hoc write parameter sanity checking in nfs_file_direct_write()
 with a call to generic_write_checks().  This should make the proper checks
 modulo the O_LARGEFILE flag, and should catch NFSv2-specific limitations by
 virtue of i_sb->s_maxbytes.

 Test plan:
 Posix compliance testing with both NFSv2 and NFSv3.

 Signed-off-by: Chuck Lever <cel@netapp.com>
 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-01-06 14:58:47 -05:00