Maintaining two parallel ways of doing synchronous writes is rather
pointless. This patch gets rid of the legacy nfs_writepage_sync(), and
replaces it with the faster asynchronous writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now that we have a copy of the symlink path in the page cache, we can pass
a struct page down to the XDR routines instead of a string buffer.
Test plan:
Connectathon, all NFS versions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the LOOKUP or GETATTR in nfs_instantiate fail, nfs_instantiate will do a
d_drop before returning. But some callers already do a d_drop in the case
of an error return. Make certain we do only one d_drop in all error paths.
This issue was introduced because over time, the symlink proc API diverged
slightly from the create/mkdir/mknod proc API. To prevent other coding
mistakes of this type, change the symlink proc API to be more like
create/mkdir/mknod and move the nfs_instantiate call into the symlink proc
routines so it is used in exactly the same way for create, mkdir, mknod,
and symlink.
Test plan:
Connectathon, all versions of NFS.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
include/linux/sunrpc/clnt.h already includes include/linux/sunrpc/xprt.h.
We can remove xprt.h from source files that already include clnt.h.
Likewise include/linux/sunrpc/timer.h.
Test plan:
Compile kernel with CONFIG_NFS enabled.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add a set_capabilities NFS RPC op so that the server capabilities can be set.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add a lookup filehandle NFS RPC op so that a file handle can be looked up
without requiring dentries and inodes and other VFS stuff when doing an NFS4
pathwalk during mounting.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
Neil Brown observed that the current limit of 32 bytes isn't enough to hold two
ip addresses and the rest of the stuff we're putting in it, so it's often
truncated to the point where it's unlikely to be unique. This can cause
spurious CLID_INUSE's from the server.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from fc8c17ec251e984ab3df9182ed097aa5b577c915 commit)
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>
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>
Respond to a moved error on NFS lookup by setting up the referral.
Note: We don't actually follow the referral during lookup/getattr, but
later when we detect fsid mismatch in inode revalidation (similar to the
processing done for cloning submounts). Referrals will have fake attributes
until they are actually followed or traversed.
Signed-off-by: Manoj Naik <manoj@almaden.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use component4-style formats for decoding list of servers and pathnames in
fs_locations.
Signed-off-by: Manoj Naik <manoj@almaden.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 allows for the fact that filesystems may be replicated across
several servers or that they may be migrated to a backup server in case of
failure of the primary server.
fs_locations is an NFSv4 operation for retrieving information about the
location of migrated and/or replicated filesystems.
Based on an initial implementation by Jiaying Zhang <jiayingz@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This should enable us to detect if we are crossing a mountpoint in the
case where the server is exporting "nohide" mounts.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up use of page_array, and fix an off-by-one error noticed by Tom
Talpey which causes kmalloc calls in cases where using the page_array
is sufficient.
Test plan:
Normal client functional testing with r/wsize=32768.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
This patch inverts the callback hierarchy for NFS write calls.
Instead of having the NFSv2/v3/v4-specific code set up the RPC callback
ops, we allow the original caller to do so. This allows for more
flexibility w.r.t. how to set up and tear down the nfs_write_data
structure while still allowing the NFSv3/v4 code to perform error
handling.
The greater flexibility is needed by the asynchronous O_DIRECT code, which
wants to be able to hold on to the original nfs_write_data structures after
the WRITE RPC call has completed in order to be able to replay them if the
COMMIT call determines that the server has rebooted.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Upon return of a write delegation, the server will almost always bump the
change attribute. Ensure that we pick up that change so that we don't
invalidate our data cache unnecessarily.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
Trond Myklebust
Al Viro
Chuck Lever
David Howells
J. Bruce Fields
Chuck Lever
Manoj Naik