Allow to query xrpt_switch attributes. Currently showing the following
fields of the rpc_xprt_switch structure: xps_nxprts, xps_nactive,
xps_queuelen.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

Allow to query transport's attributes. Currently showing following
fields of the rpc_xprt structure: state, last_used, cong, cwnd,
max_reqs, min_reqs, num_reqs, sizes of queues binding, sending,
pending, backlog.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

Allow to query and set the destination's address of a transport.
Setting of the destination address is allowed only for TCP or RDMA
based connections.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

Add individual transport directories under each transport switch
group. For instance, for each nconnect=X connections there will be
a transport directory. Naming conventions also identifies transport
type -- xprt-<id>-<type> where type is udp, tcp, rdma, local, bc.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

An rpc client uses a transport switch and one ore more transports
associated with that switch. Since transports are shared among
rpc clients, create a symlink into the xprt_switch directory
instead of duplicating entries under each rpc client.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

Add xprt_switch directory to the sysfs and create individual
xprt_swith subdirectories for multipath transport group.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

We need to keep track of the type for a given transport.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>

This is used to uniquely identify sunrpc multipath objects in /sys.

Signed-off-by: Dan Aloni <dan@kernelim.com>

This adds a unique identifier for a sunrpc transport in sysfs, which is
similarly managed to the unique IDs of clients.

Signed-off-by: Dan Aloni <dan@kernelim.com>

We won't have a task structure when we go to change IP addresses, so
check for one before calling the WARN_ON() to avoid crashing.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

These will eventually have files placed under them for sysfs operations.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

For network namespace separation.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

This is where we'll put per-rpc_client related files

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

When a copy offload is performed, we do not expect the source file to
change other than perhaps to see the atime be updated.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the result of a copy offload or clone operation is to grow the
destination file size, then we should update it. The reason is that when
a client holds a delegation, it is authoritative for the file size.

Fixes: 16abd2a ("NFSv4.2: fix client's attribute cache management for copy_file_range")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Currently if a major timeout value is reached, but the minor value has
not been reached, an ETIMEOUT will not be sent back to the caller.
This can occur if the v4 server is not responding to requests and
retrans is configured larger than the default of two.

For example, A TCP mount with a configured timeout value of 50 and a
retransmission count of 3 to a v4 server which is not responding:

1. Initial value and increment set to 5s, maxval set to 20s, retries at 3
2. Major timeout is set to 20s, minor timeout set to 5s initially
3. xport_adjust_timeout() is called after 5s, retry with 10s timeout,
   minor timeout is bumped to 10s
4. And again after another 10s, 15s total time with minor timeout set
   to 15s
5. After 20s total time xport_adjust_timeout is called as major timeout is
   reached, but skipped because the minor timeout is not reached
       - After this time the cpu spins continually calling
       	 xport_adjust_timeout() and returning 0 for 10 seconds.
	 As seen on perf sched:
   	 39243.913182 [0005]  mount.nfs[3794] 4607.938      0.017   9746.863
6. This continues until the 15s minor timeout condition is reached (in
   this case for 10 seconds). After which the ETIMEOUT is processed
   back to the caller, the cpu spinning stops, and normal operations
   continue

Fixes: 7de62bc ("SUNRPC dont update timeout value on connection reset")
Signed-off-by: Chris Dion <Christopher.Dion@dell.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

This tracepoint can crash when dereferencing snd_task because
when some transports connect, they put a cookie in that field
instead of a pointer to an rpc_task.

BUG: KASAN: use-after-free in trace_event_raw_event_xprt_writelock_event+0x141/0x18e [sunrpc]
Read of size 2 at addr ffff8881a83bd3a0 by task git/331872

CPU: 11 PID: 331872 Comm: git Tainted: G S                5.12.0-rc2-00007-g3ab6e585a7f9 #1453
Hardware name: Supermicro SYS-6028R-T/X10DRi, BIOS 1.1a 10/16/2015
Call Trace:
 dump_stack+0x9c/0xcf
 print_address_description.constprop.0+0x18/0x239
 kasan_report+0x174/0x1b0
 trace_event_raw_event_xprt_writelock_event+0x141/0x18e [sunrpc]
 xprt_prepare_transmit+0x8e/0xc1 [sunrpc]
 call_transmit+0x4d/0xc6 [sunrpc]

Fixes: 9ce07ae ("SUNRPC: Replace dprintk() call site in xprt_prepare_transmit")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

A separate tracepoint can be left enabled all the time to capture
rare but important retransmission events. So for example:

kworker/u26:3-568   [009]   156.967933: xprt_retransmit:      task:44093@5 xid=0xa25dbc79 nfsv3 WRITE ntrans=2

Or, for example, enable all nfs and nfs4 tracepoints, and set up a
trigger to disable tracing when xprt_retransmit fires to capture
everything that leads up to it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

I've hit some crashes that occur in the xprt_rdma_inject_disconnect
path. It appears that, for some provides, rdma_disconnect() can
take so long that the transport can disconnect and release its
hardware resources while rdma_disconnect() is still running,
resulting in a UAF in the provider.

The transport's fault injection method may depend on the stability
of transport data structures. That means it needs to be invoked
only from contexts that hold the transport write lock.

Fixes: 4a06825 ("SUNRPC: Transport fault injection")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Currently the client ignores the value of the sr_eof of the SEEK
operation. According to the spec, if the server didn't find the
requested extent and reached the end of the file, the server
would return sr_eof=true. In case the request for DATA and no
data was found (ie in the middle of the hole), then the lseek
expects that ENXIO would be returned.

Fixes: 1c6dcbe ("NFS: Implement SEEK")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We (adam zabrocki, alexander matrosov, alexander tereshkin, maksym
bazalii) observed the check:

	if (fh->size > sizeof(struct nfs_fh))

should not use the size of the nfs_fh struct which includes an extra two
bytes from the size field.

struct nfs_fh {
	unsigned short         size;
	unsigned char          data[NFS_MAXFHSIZE];
}

but should determine the size from data[NFS_MAXFHSIZE] so the memcpy
will not write 2 bytes beyond destination.  The proposed fix is to
compare against the NFS_MAXFHSIZE directly, as is done elsewhere in fs
code base.

Fixes: d67ae82 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Nikola Livic <nlivic@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the server returns a filehandle with an invalid length, then trace
that, and return an EREMOTEIO error.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We would like the ability to record other XDR errors, particularly
those that are due to server bugs.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

When the server returns a different operation than we expected, then
trace that.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

There are lots of attributes, and they are crowding out the bit space.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

NFS_INO_REVAL_FORCED is intended to tell us that the cache needs
revalidation despite the fact that we hold a delegation. We shouldn't
need to store it anymore, though.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the nlink changes, then so will the ctime.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If we're trying to update the inode because a previous update left the
cache in a partially unrevalidated state, then allow the update if the
change attrs match.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the NFSv4.2 server supports the 'change_attr_type' attribute, then
allow the client to optimise its attribute cache update strategy.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

The change_attr_type allows the server to provide a description of how
the change attribute will behave. This again will allow the client to
optimise its behaviour w.r.t. attribute revalidation.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

When the client is caching data and a write delegation is held, then the
server may send a CB_GETATTR to query the attributes. When this happens,
the client is supposed to bump the change attribute value that it
returns if it holds cached data.
However that process uses a value that is stored in the delegation. We
do not want to bump the change attribute held in the inode.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

At least two extra fields have been added to fsinfo since this was last
updated.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We should not be invalidating the access or acl caches in
nfs_check_inode_attributes(), since the point is we're unsure about
whether the contents of the struct nfs_fattr are fully up to date.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Commit 0b46726 ("NFS: Fix attribute revalidation") changed the way
we populate the 'invalid' attribute, and made the line that strips away
the NFS_INO_INVALID_ATTR bits redundant.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>