The final place where congestion control state is adjusted is in
 xprt_release, where each request is finally released.  Add a callout
 there to allow transports to perform additional processing when a
 request is about to be released.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for significant
 regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 A new interface that allows transports to adjust their congestion window
 using the Van Jacobson implementation in xprt.c is provided.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for
 significant regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Allow transports to hook the retransmit timer interrupt.  Some transports
 calculate their congestion window here so that a retransmit timeout has
 immediate effect on the congestion window.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for significant
 regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The next method we abstract is the one that releases a transport,
 allowing another task to have access to the transport.

 Again, one generic version of this is provided for transports that
 don't need the RPC client to perform congestion control, and one
 version is for transports that can use the original Van Jacobson
 implementation in xprt.c.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for
 significant regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The next several patches introduce an API that allows transports to
 choose whether the RPC client provides congestion control or whether
 the transport itself provides it.

 The first method we abstract is the one that serializes access to the
 RPC transport to prevent the bytes from different requests from mingling
 together.  This method provides proper request serialization and the
 opportunity to prevent new requests from being started because the
 transport is congested.

 The normal situation is for the transport to handle congestion control
 itself.  Although NFS over UDP was first, it has been recognized after
 years of experience that having the transport provide congestion control
 is much better than doing it in the RPC client.  Thus TCP, and probably
 every future transport implementation, will use the default method,
 xprt_lock_write, provided in xprt.c, which does not provide any kind
 of congestion control.  UDP can continue using the xprt.c-provided
 Van Jacobson congestion avoidance implementation.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for significant
 regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Prepare the way to remove the "xprt->nocong" variable by adding a callout
 to the RPC client transport switch API to handle setting RPC retransmit
 timeouts.

 Add a pair of generic helper functions that provide the ability to set a
 simple fixed timeout, or to set a timeout based on the state of a round-
 trip estimator.

 Test-plan:
 Use WAN simulation to cause sporadic bursty packet loss.  Look for significant
 regression in performance or client stability.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Now we can fix up the last few places that use the "xprt->stream"
 variable, and get rid of it from the rpc_xprt structure.

 Test-plan:
 Destructive testing (unplugging the network temporarily).  Connectathon
 with UDP and TCP.
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Add a generic mechanism for skipping over transport-specific headers
 when constructing an RPC request.  This removes another "xprt->stream"
 dependency.

 Test-plan:
 Write-intensive workload on a single mount point (try both UDP and
 TCP).
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Split the RPC client's main socket write path into a TCP version and a UDP
 version to eliminate another dependency on the "xprt->stream" variable.

 Compiler optimization removes unneeded code from xs_sendpages, as this
 function is now called with some constant arguments.

 We can now cleanly perform transport protocol-specific return code testing
 and error recovery in each path.

 Test-plan:
 Millions of fsx operations.  Performance characterization such as
 "sio" or "iozone".  Examine oprofile results for any changes before and
 after this patch is applied.

 Version: Thu, 11 Aug 2005 16:08:46 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Create separate connection worker functions for managing UDP and TCP
 transport sockets.  This eliminates several dependencies on "xprt->stream".

 Test-plan:
 Destructive testing (unplugging the network temporarily).  Connectathon with
 v2, v3, and v4.

 Version: Thu, 11 Aug 2005 16:08:18 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Split the socket write space callback function into a TCP version and UDP
 version, eliminating one dependence on the "xprt->stream" variable.

 Keep the common pieces of this path in xprt.c so other transports can use
 it too.

 Test-plan:
 Write-intensive workload on a single mount point.

 Version: Thu, 11 Aug 2005 16:07:51 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: change some comments to reflect the realities of the new RPC
 transport switch mechanism.  Get rid of unused xprt_receive() prototype.

 Also, organize function prototypes in xprt.h by usage and scope.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:07:21 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: remove only reference to xprt->pending from the socket transport
 implementation.  This makes a cleaner interface for other transport
 implementations as well.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:06:52 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: get rid of unnecessary socket.h and in.h includes in the generic
 parts of the RPC client.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:06:23 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: get rid of a name reference to sockets in the generic parts of the
 RPC client by renaming the sockstate field in the rpc_xprt structure.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:05:53 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: Replace the xprt_lock with something more aptly named.  This lock
 single-threads the XID and request slot reservation process.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:05:26 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: replace a name reference to sockets in the generic parts of the RPC
 client by renaming sock_lock in the rpc_xprt structure.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:05:00 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Reduce stack utilization of the RPC socket transport's send path.

 A couple of unlikely()s are added to ensure the compiler places the
 tail processing at the end of the csect.

 Test-plan:
 Millions of fsx operations.  Performance characterization such as "sio" or
 "iozone".

 Version: Thu, 11 Aug 2005 16:04:30 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Introduce block header comments and a function naming convention to the
 socket transport implementation.  Provide a debug setting for transports
 that is separate from RPCDBG_XPRT.  Eliminate xprt_default_timeout().

 Provide block comments for exposed interfaces in xprt.c, and eliminate
 the useless obvious comments.

 Convert printk's to dprintk's.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.

 Version: Thu, 11 Aug 2005 16:04:04 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Move the bulk of client-side socket-specific code into a separate source
 file, net/sunrpc/xprtsock.c.

 Test-plan:
 Millions of fsx operations.  Performance characterization such as "sio" or
 "iozone".  Destructive testing (unplugging the network temporarily, server
 reboots).  Connectathon with v2, v3, and v4.

 Version: Thu, 11 Aug 2005 16:03:38 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Clean-up: Move some code that is common to both RPC client- and server-side
 socket transports into its own source file, net/sunrpc/socklib.c.

 Test-plan:
 Compile kernel with CONFIG_NFS enabled.  Millions of fsx operations over
 UDP, client and server.  Connectathon over UDP.

 Version: Thu, 11 Aug 2005 16:03:09 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 The in-kernel portmapper does not require a reserved port for making
 bind queries.

 Test-plan:
 Tens of runs of the Connectathon locking suite with TCP and UDP
 against several other NFS server implementations using NFSv3,
 not NFSv4 (which doesn't require rpcbind).

 Version: Thu, 11 Aug 2005 16:02:43 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Implement a best practice: don't use exponential backoff when computing
 retransmit timeout values on TCP connections, but simply retransmit
 at regular intervals.

 This also fixes a bug introduced when xprt_reset_majortimeo() was added.

 Test-plan:
 Enable RPC debugging and watch timeout behavior on a NFS/TCP mount.

 Version: Thu, 11 Aug 2005 16:02:19 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Implement a best practice:  for soft mounts, an rpcbind timeout should
 cause an RPC request to fail.

 This also provides an FSM hook for retrying an rpcbind with a different
 rpcbind protocol version.  We'll use this later to try multiple rpcbind
 protocol versions when binding.  To enable this, expose the RPC error
 code returned during a portmap request to the FSM so it can make some
 decision about how to report, retry, or fail the request.

 Test-plan:
 Hundreds of passes with connectathon NFSv3 locking suite, on the client
 and server.

 Version: Thu, 11 Aug 2005 16:01:53 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Fix up xprt_connect_status: the soft timeout logic was clobbering tk_status,
 so TCP connect errors were not properly reported on soft mounts.

 Test-plan:
 Destructive testing (unplugging the network temporarily).  Connectathon
 with UDP and TCP.

 Version: Thu, 11 Aug 2005 16:01:28 -0400
Signed-off-by: NChuck Lever <cel@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 Fixes a condition whereby the kernel is returning the non-POSIX error
 EBADCOOKIE to userspace.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

[PATCH] Fix miscompare in __posix_lock_file

 If an application requests the same lock twice, the
 kernel should just leave the existing lock in place.
 Currently, it will install a second lock of the same type.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

 When doing a rename on top of an existing file that is not in use,
 the inode of the overwritten file will remain in the icache.

 The fix is to decrement i_nlink of the overwritten inode, like we
 do for unlink, rmdir etc already.

 Problem diagnosed by Olaf Kirch. This patch is a slight variation
 on his fix.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

I believe the change that broke things is introduction of
pci_fixup_parent_subordinate_busnr().

The patch here does two things:
- hunk #1 should fix the problems you've seen when you boot without
  additional "pci" kernel options;
- hunk #2 supposedly fixes boot with "pci=assign-busses" option which
  otherwise hangs Acer TM81xx machines as reported.

Please try this with and without "pci=assign-busses". If it boots,
I'd like to see 'lspci -vvx' for both cases.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix to allow SCTP_SHUTDOWN notifications to be received on 1-1 style
SCTP SOCK_STREAM sockets.

Add SCTP_SHUTDOWN notification to the receive queue before updating
the state of the association.
Signed-off-by: NSridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a number of bugs.  It cannot be reasonably split up in
multiple fixes, since all bugs interact with each other and affect the same
function:

Bug #1:
The event cache code cannot be called while a lock is held.  Therefore, the
call to ip_conntrack_event_cache() within ip_ct_refresh_acct() needs to be
moved outside of the locked section.  This fixes a number of 2.6.14-rcX
oops and deadlock reports.

Bug #2:
We used to call ct_add_counters() for unconfirmed connections without
holding a lock.  Since the add operations are not atomic, we could race
with another CPU.

Bug #3:
ip_ct_refresh_acct() lost REFRESH events in some cases where refresh
(and the corresponding event) are desired, but no accounting shall be
performed.  Both, evenst and accounting implicitly depended on the skb
parameter bein non-null.   We now re-introduce a non-accounting
"ip_ct_refresh()" variant to explicitly state the desired behaviour.
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As noted by Alexey Dobriyan, the DEBUGP statement prints the wrong
callID.
Signed-off-by: NHarald Welte <laforge@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NVlad Drukker <vlad@storewiz.com>
Acked-by: NStephen Hemminger <shemminger@osdl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the introduction of TSO pcount a year ago, it has been possible
for tcp_fragment() to cause packets_out to decrease.  Prior to that,
tcp_retrans_try_collapse() was the only way for that to happen on the
retransmission path.

When this happens with Reno, it is possible for sasked_out to become
invalid because it is only an estimate and not tied to any particular
packet on the retransmission queue.

Therefore we need to adjust sacked_out as well as left_out in the Reno
case.  The following patch does exactly that.

This bug is pretty difficult to trigger in practice though since you
need a SACKless peer with a retransmission that occurs just as the
cached MTU value expires.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I've recently discovered the real functionality of device-mapper snapshots,
and since they are not well known, I've decided to write some docs for
them.
Signed-off-by: NPaolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

nfs_readpage_release() causes an oops while accessing a file with NFS
debugging turned on (echo 32767 > /proc/sys/sunrpc/nfs_debug) and a kernel
built with CONFIG_DEBUG_SLAB.

This patch moves the debugging statement above nfs_release_request() to
avoid accessing freed memory.
Signed-off-by: NNick Wilson <njw@osdl.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Problem: In some circumstances, bd_claim() is returning the wrong error
code.

If we try to swapon an unused block device that isn't swap formatted, we
get -EINVAL.  But if that same block device is already mounted, we instead
get -EBUSY, even though it still isn't a valid swap device.

This issue came up on the busybox list trying to get the error message
from "swapon -a" right.  If a swap device is already enabled, we get -EBUSY,
and we shouldn't report this as an error.  But we can't distinguish the two
-EBUSY conditions, which are very different errors.

In the code, bd_claim() returns either 0 or -EBUSY, but in this case busy
means "somebody other than sys_swapon has already claimed this", and
_that_ means this block device can't be a valid swap device.  So return
-EINVAL there.
Signed-off-by: NRob Landley <rob@landley.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>