Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add an orig_dgid attribute in sysfs for SRP scsi_hosts, so that
userspace can tell what the original dgid value written to the
add_target file was, even if the connection is redirected to a
different port while connecting.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The IPoIB CM spec allows the use of a single connection in both
active->passive and passive->active directions.  The current Linux
code uses one connection for both directions, but if another node only
uses one connection for both directions, we oops when we try to look
up the passive connection.  Fix by checking that qp_context is
non-NULL before dereferencing it.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>

If skb allocation fails when we start the device, we call
ipoib_cm_dev_stop() even though ipoib_cm_dev_open() did not run to
completion, so we pass an invalid pointer to ib_destroy_cm_id and get
an oops.

Fix by clearing cm.id on error, and testing it in cm_dev_stop().
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=561>
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are quite a few places in ipoib_cm.c where we know IRQs are
enabled because we do something that sleeps in the same function, so
we can convert several occurrences of spin_lock_irqsave() to a plain
spin_lock_irq().  This cleans up the source a little and makes the
code smaller too:

add/remove: 0/0 grow/shrink: 1/5 up/down: 3/-51 (-48)
function                                     old     new   delta
ipoib_cm_tx_reap                             403     406      +3
ipoib_cm_stale_task                          146     145      -1
ipoib_cm_dev_stop                            173     172      -1
ipoib_cm_tx_handler                          964     956      -8
ipoib_cm_rx_handler                          956     937     -19
ipoib_cm_skb_reap                            212     190     -22
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

To support destinations that are not on the local IB subnet, IPoIB
should include the GRH information when constructing an address
handle.  Using the existing ib_init_ah_from_path() call will do this
for us.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>

There's no point in printing the opcode field in the completion
handling debugging output, since the type of completion is already
printed at the beginning of the line.  In fact the opcode field is not
even defined for completions with a status other than success.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Receive buffers need to be mapped with DMA_FROM_DEVICE.  Incorrectly
mapping with DMA_TO_DEVICE causes a hard lock on ppc64 machines with
an IOMMU.

This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=431>
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When a connection is terminated asynchronously from the iSCSI layer's
perspective, iSER needs to notify the iSCSI layer that the connection
has failed.  This is done using a workqueue (switched to from the iSER
tasklet context).  Meanwhile, the connection object (that holds the
work struct) is released.  If the workqueue function wasn't called
yet, it will be called later with a NULL pointer, which will crash the
kernel.

The context switch (tasklet to workqueue) is not required, and
everything can be done from the iSER tasklet. This eliminates the NULL
work struct bug (and simplifies the code).
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The SCSI midlayer may abort a command that was already sent.  If the
initiator is still trying to send the command (or data-out PDUs for
that command), the QP may time out after the midlayer times
out. Therefore, when aborting the command, iSER may still have
references for the command's buffers.  When sending these PDUs, the
sends will complete with an error and their resources will be released
then.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

->neigh_destructor() is killed (not used), replaced with
->neigh_cleanup(), which is called when neighbor entry goes to dead
state. At this point everything is still valid: neigh->dev,
neigh->parms etc.

The device should guarantee that dead neighbor entries (neigh->dead !=
0) do not get private part initialized, otherwise nobody will cleanup
it.

I think this is enough for ipoib which is the only user of this thing.
Initialization private part of neighbor entries happens in ipib
start_xmit routine, which is not reached when device is down.  But it
would be better to add explicit test for neigh->dead in any case.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The packet length checks in ipoib are broken: we add 4 bytes (IPoIB
encapsulation header) when sending a packet, not 20 bytes (hardware
address length) to each packet.  Therefore, if connected mode is
enabled so that the interface MTU is larger than the multicast MTU,
IPoIB may end up trying to send too-long multicast packets.  For
example, multicast is broken if a message of size 2048 bytes is sent
on an interface with UD MTU 2048, because 2048 is bigger than the real
limit of 2044 but the code tests against the wrong limit of 2060.

This patch fixes <https://bugs.openfabrics.org/show_bug.cgi?id=418>,
submitted by Scott Weitzenkamp <sweitzen@cisco.com>.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The connected mode code added the possibility that an neigh struct
gets freed in the list_for_each_entry() loop in path_rec_completion(),
which causes a use-after-free.  Fix this by changing to the _safe
variant of the list walking macro.

This was spotted by the Coverity checker (CID 1567).
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

There's a race between ipoib_mcast_leave() and ipoib_mcast_join_finish()
where we can try to detach from a multicast group before we've
attached to it.  Fix this by reordering the code in ipoib_mcast_leave
to free the multicast group first, which waits for the multicast
callback thread (which calls ipoib_mcast_join_finish()) to complete
before detaching from the group.
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The sense of the time_after_eq() test in ipoib_cm_stale_task() is
reversed so that only non-stale connections are reaped.  Fix this by
changing to time_before_eq().

Noticed by Pradeep Satyanarayana <pradeep@us.ibm.com>.
Signed-off-by: NMichael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Do netif_carrier_on() right after the IPv4 broadcast multicast group
is joined, rather than waiting for all of the initial set of multicast
group joins to finish.  This allows at least IPv4 traffic to limp
along on broken fabrics where not all multicast groups can be joined.
Signed-off-by: NShirley Ma <xma@us.ibm.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

An asynchronous event carries the port number that the event occurred
on, so there's no reason for an IPoIB interface to process an event
associated with a different local HCA port.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If path_rec_completion() is passed a non-NULL path record pointer
along with an unsuccessful status value, the tracing code incorrectly
prints the (invalid) DLID from the path record rather than the more
interesting status code.  The actual logic of the function correctly
uses the path record only if the status indicates a successful lookup.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Now that low-level drivers handle the conversion from an absolute rate
to a relative rate, there's no need for the IPoIB driver to keep track
of the local port's data rate.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Avoid the overhead of freeing/reallocating and mapping/unmapping for
DMA pages that have not been written to by hardware.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The IB SA tracks multicast join/leave requests on a per port basis and
does not do any reference counting: if two users of the same port join
the same group, and one leaves that group, then the SA will remove the
port from the group even though there is one user who wants to stay a
member left.  Therefore, in order to support multiple users of the
same multicast group from the same port, we need to perform reference
counting locally.

To do this, add an multicast submodule to ib_sa to perform reference
counting of multicast join/leave operations.  Modify ib_ipoib (the
only in-kernel user of multicast) to use the new interface.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

ipoib_cm_alloc_rx_skb() might be called from IRQ context, so it must
use dev_kfree_skb_any(), not kfree_skb().
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Change the permissions of the "mode" sysfs attribute to be S_IWUSR
instead of S_IWUGO.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The following patch adds experimental support for IPoIB connected
mode, as defined by the draft from the IETF ipoib working group.  The
idea is to increase performance by increasing the MTU from the maximum
of 2K (theoretically 4K) supported by IPoIB on top of UD.  With this
code, I'm able to get 800MByte/sec or more with netperf without
options on a Mellanox 4x back-to-back DDR system.

Some notes on code:
1. SRQ is used for scalability to large cluster sizes
2. Only RC connections are used (UC does not support SRQ now)
3. Retry count is set to 0 since spec draft warns against retries
4. Each connection is used for data transfers in only 1 direction, so
   each connection is either active(TX) or passive (RX).  2 sides that
   want to communicate create 2 connections.
5. Each active (TX) connection has a separate CQ for send completions -
   this keeps the code simple without CQ resize and other tricks
6. To detect stale passive side connections (where the remote side is
   down), we keep an LRU list of passive connections (updated once per
   second per connection) and destroy a connection after it has been
   unused for several seconds. The LRU rule makes it possible to avoid
   scanning connections that have recently been active.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This lets the network core have the ability to handle suspend/resume
issues, if it wants to.

Thanks to Frederik Deweerdt <frederik.deweerdt@gmail.com> for the arm
driver fixes.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

When there is a call to send_tsk_mgmt SRP posts a send and waits for 5
seconds to get a response.

When the QP is in the error state it is obvious that there will be no
response so it is quite useless to wait.  In fact, the timeout causes
SRP to wait a long time to reconnect when a QP error occurs. (Each
abort and each reset_device calls send_tsk_mgmt, which waits for the
timeout).  The following patch solves this problem by identifying the
failure and returning an immediate error code.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Checks if the kmalloc in match_strdup() was successful, and bail out
on looking at the token if it failed.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

iSER limits the number of outstanding PDUs to send. When this threshold
is reached, it should return an error code (-ENOBUFS) instead of setting
the suspend_tx bit (which should be used only by libiscsi).
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

struct srp_device.fmr_page_mask was unsigned long, which means that
the top part of addresses above 4G was being chopped off on 32-bit
architectures.  Of course nothing good happens when data from SRP
targets is DMAed to the wrong place.

Fix this by changing fmr_page_mask to u64, to match the addresses
actually used by IB devices.

Thanks to Brian Cain <Brian.Cain@ge.com> and David McMillen
<davem@systemfabricworks.com> for help diagnosing the bug and testing
the fix.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Move the initialization of ipoib_neigh's skb_queue into
ipoib_neigh_alloc(), since commit 2745b5b7 ("IPoIB: Fix skb leak when
freeing neighbour") will make iterate over the skb_queue to free any
packets left over when freeing the ipoib_neigh structure.

This fixes a crash when freeing ipoib_neigh structures allocated in
ipoib_mcast_send(), which otherwise don't have their skb_queue
initialized.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Convert iSER to use the new verbs DMA mapping functions for kernel
verbs consumers.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Convert SRP to use the new verbs DMA mapping functions for kernel
verbs consumers.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Convert IPoIB to use the new DMA mapping functions
for kernel verbs consumers.
Signed-off-by: NRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Remove variables that are set but then never looked at in the iSER
initiator.  These cleanups came from David Binderman's list of "set
but never used" warnings from icc.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

This facility provides three entry points:

	ilog2()		Log base 2 of unsigned long
	ilog2_u32()	Log base 2 of u32
	ilog2_u64()	Log base 2 of u64

These facilities can either be used inside functions on dynamic data:

	int do_something(long q)
	{
		...;
		y = ilog2(x)
		...;
	}

Or can be used to statically initialise global variables with constant values:

	unsigned n = ilog2(27);

When performing static initialisation, the compiler will report "error:
initializer element is not constant" if asked to take a log of zero or of
something not reducible to a constant.  They treat negative numbers as
unsigned.

When not dealing with a constant, they fall back to using fls() which permits
them to use arch-specific log calculation instructions - such as BSR on
x86/x86_64 or SCAN on FRV - if available.

[akpm@osdl.org: MMC fix]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David Howells <dhowells@redhat.com>
Cc: Wojtek Kaniewski <wojtekka@toxygen.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

ipoib_neigh_free() is sometimes called while neighbour is still alive,
so it might still have queued skbs.  Fix skb leak in this case.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>