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>

SRP reallocates the IU buffers for tx_ring and rx_ring without freeing
the old buffers when it reconnects to a target.  Fix this by keeping
the old IU buffers around.
Signed-off-by: NVu Pham <vu@mellanox.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

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

Set the Scsi_Host's max_cmd_len from 12 (default) to 16 for
SRP. Otherwise scsi_dispatch_cmd() won't pass down certain commands
such as READ CAPACITY 16, required for supporting disks > 2TB.
Signed-off-by: NArne Redlich <arne.redlich@xiranet.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix up for make allyesconfig.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>

IPoIB assumes that high (reserved) octet in the hardware address is 0,
and copies it into the QPN.  This violates RFC 4391 (which requires
that the high 8 bits are ignored on receive), and will result in an
invalid QPN being used when interoperating with IPoIB connected mode.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When a connection is started (a new connection or a recovered one),
iSER should prepare its resources for full-featured mode and only then
notify the iSCSI layer that it is ready to start queueing commands.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

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

Enable multiple concurrent connections to the same SRP target:

1) Use port GUID instead of node GUID in the initiator port
   identifier.  This allows connections to be made from multiple HCA
   ports at the same time.
2) Let the user specify the identifier extention when adding the
   device.  This allows userspace to make multiple connections even
   from the same port, if it wants too.

Without this, only one connection can be made from any given HCA, even
if it has multiple ports, because we don't use multi-channel mode, so
targets will only allow one connection from a given initiator port ID.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

scsi_host_alloc() already allocates with kzalloc(), so the struct Scsi_Host
is zeroed out, including the private data portion.  Remove the redundant
memset that zeros this out again in the SRP initiator.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Signed-off-by: NAdrian Bunk <bunk@stusta.de>

Fix the description of iSER in Kconfig.  It is not accurate.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

iSER uses the DMA mapping api to map the page holding the
SCSI command data to the HCA DMA address space. When the
command data is not aligned for RDMA, the data is copied
to/from an allocated buffer which in turn is used for
executing this command. The pages associated with the
command must be unmapped before being touched.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

iSER uses a data transaction object (struct iser_dto) as part
of its IB data descriptors (struct iser_desc) management.
It also uses a hierarchy of connection structures pointing to
each other. A DTO may exist even after the iscsi_iser connection
pointed by it is destroyed (eg one that is bound to a post
receive buffer which was flushed by the IB HW). Hence DTOs need
point to the lowest connection, which is struct iser_conn.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

The following patches reduce the size of the VFS inode structure by 28 bytes
on a UP x86.  (It would be more on an x86_64 system).  This is a 10% reduction
in the inode size on a UP kernel that is configured in a production mode
(i.e., with no spinlock or other debugging functions enabled; if you want to
save memory taken up by in-core inodes, the first thing you should do is
disable the debugging options; they are responsible for a huge amount of bloat
in the VFS inode structure).

This patch:

The filesystem or device-specific pointer in the inode is inside a union,
which is pretty pointless given that all 30+ users of this field have been
using the void pointer.  Get rid of the union and rename it to i_private, with
a comment to explain who is allowed to use the void pointer.  This is just a
cleanup, but it allows us to reuse the union 'u' for something something where
the union will actually be used.

[judith@osdl.org: powerpc build fix]
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NJudith Lebzelter <judith@osdl.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NEli Cohen <eli@dev.mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

IPoIB doesn't use anything from <linux/vmalloc.h>, so don't include it.
Signed-off-by: NDotan Barak <dotanb@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When ipoib_ib_dev_flush() is called because of a port event, the
driver needs to rejoin all multicast groups, since the flush will call
ipoib_mcast_dev_flush() (via ipoib_ib_dev_down()).  Otherwise no
(non-broadcast) multicast groups will be rejoined until the networking
core calls ->set_multicast_list again, and so multicast reception will
be broken for potentially a long time.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

RFC 4391 ("Transmission of IP over InfiniBand (IPoIB)") says:

  If the IB multicast group does not already exist, one must be
  created first with the IPoIB link MTU.  The MGID MUST use the same
  P_Key, Q_Key, SL, MTU, and HopLimit as those used in the
  broadcast-GID.  The rest of attributes SHOULD follow the values used
  in the broadcast-GID as well.

However, the current IPoIB driver is only setting the attributes
required by the InfiniBand spec to create a multicast group, so in
particular the MTU and HopLimit are not being set.  Add these
attributes when creating MCGs, and also set the Rate attribute, since
IPoIB pays attention to that attribute as well.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

iSER won't build without CONFIG_INET enabled, so make Kconfig reflect that.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Require users to register with SA module, to prevent the sa_query
module text from going away while an SA query callback is still
running.  Update all in-tree users for the new interface.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NSean Hefty <sean.hefty@intel.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Split up ipoib_ib_handle_wc() into ipoib_ib_handle_rx_wc() and
ipoib_ib_handle_tx_wc() to make the code easier to read.  This will
also help implement NAPI in the future.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fast Memory Registration (fmr) is used to register for rdma an sg whose
elements are not linearly sequential after dma mapping.

The IB verbs layer provides an "all dma memory MR (memory region)" which
can be used for RDMA-ing a dma linearly sequential buffer.

Change the code to use the dma mr instead of doing fmr when dma mapping
produces a single dma entry sg.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

fix and add some debug prints related to iser
handling of memory for rdma.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

As iser is able to use at most one rdma operation for the
execution of a scsi command, and registration of the sg
associated with scsi command has its restrictions, the code
checks if an sg is "aligned for rdma".

Alignment for rdma is measured in "fmr page" units whose
possible resolutions are different between HCAs and can be
smaller, equal or bigger to the system page size.

When the system page size is bigger than 4KB (eg the default
with ia64 kernels) there a bigger chance that an sg would be
aligned for rdma if the fmr page size is 4KB.

Change the code to create FMR whose pages are of size 4KB
and to take that into account when processing the sg.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Currently, the data length of a command coming down from scsi-ml
is limited only by the size of its sg list (sg_tablesize). The
max data length may be different for different page size values.
By setting max_sectors, we limit the data length to
max_sectors*512 bytes.
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

dma mapping may include a "compaction" of the sg associated with scsi command.
Hence, the size of the maximal prefix of the SG which is aligned for rdma must be
compared against the length of the dma mapped sg (mem->dma_nents) and not against
the size of it before it was mapped (mem->size).
Signed-off-by: NErez Zilber <erezz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Modifications to the existing rdma header files, core files, drivers,
and ulp files to support iWARP, including:
 - Hook iWARP CM into the build system and use it in rdma_cm.
 - Convert enum ib_node_type to enum rdma_node_type, which includes
   the possibility of RDMA_NODE_RNIC, and update everything for this.
Signed-off-by: NTom Tucker <tom@opengridcomputing.com>
Signed-off-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Remove some trailing whitespace that has snuck in despite the best
efforts of whitespace=error-all.  Also fix a few other whitespace
bogosities.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add local_ib_device and local_ib_port attributes to srp scsi_host.
These are needed when we want to connect to the same target through
multiple distinct ports.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Prevent flush task from freeing the ipoib_neigh pointer, while
ipoib_start_xmit() is accessing the ipoib_neigh through the pointer it
has loaded from the skb's hardware address.
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

When a send-only multicast group join fails, mcast->query must be set
to NULL.  Otherwise, IPoIB will never retry the join and the multicast
group will never be reachable.
Signed-off-by: NEli Cohen <eli@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

If there is a problem in the connection, the SCSI mid-layer will
eventually call srp_reset_host(), which will call srp_reconnect(), so
we do not need to schedule a call to srp_reconnect_work() from
srp_completion().

Removing this prevents srp_reset_host() from failing if a reconnect
scheduled from srp_completion() is already in progress, which in turn
was causing crashes as both SCSI midlayer and srp_reconnect() were
cancelling commands.
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

iSCSI RFC states that the first burst length must be smaller than the
max burst length. We currently assume targets will be good, but that may
not be the case, so this patch adds a check.

This patch also moves the unsol data out offset to the lib so the LLDs
do not have to track it.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Remove references to the IPoIB IETF working group as it has been closed.
Signed-off-by: NOr Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Data corruption has been seen with Mellanox SRP targets when FMRs
create a memory region with I/O virtual address != 0.  Add a
workaround that disables FMR merging for Mellanox targets (OUI 0002c9).
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Protect against srp_reset_device() clearing the req_queue while
srp_reconnect_target() is in progress (note that state change at
the top of srp_reconnect_target() is not sufficient for this since
srp_reset_device() ignores the state).
Signed-off-by: NIshai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: NMichael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>