Replace kmalloc()+memset(,0,) with kzalloc(), for a net savings of 35
source lines and about 500 bytes of text.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Userspace CQs that have no completion event channel attached end up
with their cq_context set to NULL.  However, asynchronous events like
"CQ overrun" can still occur on such CQs, so add a uverbs_file member
to struct ib_ucq_object that we can follow to deliver these events.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix class_device_create() calls to match the new prototype which
takes a parent device pointer.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Move ib_uverbs module to using cdev_alloc() and class_device_create()
so that we can handle device lifetime properly.  Now we can make sure
we keep all of our data structures around until the last way to reach
them is gone.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add idr_destroy() calls to the module_exit() functions of the four IB
driver modules that use idrs, so we don't leak idr_layer_cache objects
when these modules are unloaded.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add kernel support for userspace calling poll CQ, request CQ
notification, post send, post receive, post SRQ receive, create AH and
destroy AH commands.  These commands allow us to support userspace
verbs for devices that can't perform these operations directly from
userspace (eg the PathScale HCA).
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Give each device a uverbs_cmd_mask, so that a low-level driver can
control which methods may be called on behalf of userspace.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

A couple of functions were missing spin_unlock calls in error paths.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add abi_version attribute to uverbs class devices to allow for
ABI versioning of device-specific interfaces.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Introduce new userspace verbs ABI version 3.  This eliminates some
unneeded commands, and adds support for user-created completion
channels.  This cleans up problems with file leaks on error paths, and
also makes sure that file descriptors are always installed into the
correct process.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Al Viro pointed out that the current IB userspace verbs interface
allows userspace to cause mischief by closing file descriptors before
we're ready, or issuing the same command twice at the same time.  This
patch closes those races, and fixes other obvious problems such as a
module reference leak.

Some other interface bogosities will require an ABI change to fix
properly, so I'm deferring those fixes until 2.6.15.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

completion events after destroying a CQ, QP or SRQ.  We do this by
sweeping the event lists before returning from a destroy calls, and
then return the number of events already reported before the destroy
call.  This allows userspace wait until it has processed all events
for an object returned from the kernel before it frees its context for
the object.

The ABI of the destroy CQ, destroy QP and destroy SRQ commands has to
change to return the event count, so bump the ABI version from 1 to 2.
The userspace libibverbs library has already been updated to handle
both the old and new ABI versions.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add SRQ support to userspace verbs module.  This adds several commands
and associated structures, but it's OK to do this without bumping the
ABI version because the commands are added at the end of the list so
they don't change the existing numbering.  There are two cases to
worry about:

1. New kernel, old userspace.  This is OK because old userspace simply
   won't try to use the new SRQ commands.  None of the old commands are
   changed.

2. Old kernel, new userspace.  This works perfectly as long as
   userspace doesn't try to use SRQ commands.  If userspace tries to
   use SRQ commands, it will get EINVAL, which is perfectly
   reasonable: the kernel doesn't support SRQs, so we couldn't do any
   better.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Make some lawyers happy and add copyright notices for people who
forgot to include them when they actually touched the code.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Fix a use-after-free bug in userspace verbs cleanup: we can't touch
mr->device after we free mr by calling ib_dereg_mr().
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add support for O_ASYNC notifications on userspace verbs
completion and asynchronous event file descriptors.
Signed-off-by: NGleb Natapov <glebn@voltaire.com>
Signed-off-by: NRoland Dreier <rolandd@cisco.com>

Add the core of the InfiniBand userspace verbs implementation, including
creating character device nodes, dispatching requests from userspace, and
passing event notifications back up to userspace.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>