Lockdep warns because uverbs is trying to take uobj->mutex when it
already holds that lock. This is because there are really multiple
types of uobjs even though all of their locks are initialized in
common code.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
ib_uverbs_create_ah() and ib_uverbs_create_srq() did not release the
PD's read lock in their error paths, which lead to deadlock when
destroying the PD.
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Store away the user handle passed in from userspace when creating an
SRQ, so that the kernel can return the correct handle when an SRQ
asynchronous event occurs. (A 0 was incorrectly stored as the user
handle as part of the changes in 9ead190b, "IB/uverbs: Don't serialize
with ib_uverbs_idr_mutex")
Signed-off-by: Roland Dreier <rolandd@cisco.com>
In ib_uverbs_post_send(), move the "out:" label after the loop that
frees the list of work requests, since the only place that jumps there
is before any work requests could possibly be added to the list.
This removes a compile warning: "is_ud might be used uninitialized in
this function".
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Currently, all userspace verbs operations that call into the kernel
are serialized by ib_uverbs_idr_mutex. This can be a scalability
issue for some workloads, especially for devices driven by the ipath
driver, which needs to call into the kernel even for datapath
operations.
Fix this by adding reference counts to the userspace objects, and then
converting ib_uverbs_idr_mutex into a spinlock that only protects the
idrs long enough to take a reference on the object being looked up.
Because remove operations may fail, we have to do a slightly funky
two-step deletion, which is described in the comments at the top of
uverbs_cmd.c.
This also still leaves ib_uverbs_idr_lock as a single lock that is
possibly subject to contention. However, the lock hold time will only
be a single idr operation, so multiple threads should still be able to
make progress, even if ib_uverbs_idr_lock is being ping-ponged.
Surprisingly, these changes even shrink the object code:
add/remove: 23/5 grow/shrink: 4/21 up/down: 633/-693 (-60)
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Factor out common code for adding a userspace object to an idr into a
function idr_add_uobj(). This shrinks both the source and object code:
add/remove: 1/0 grow/shrink: 0/6 up/down: 57/-220 (-163)
function old new delta
idr_add_uobj - 57 +57
ib_uverbs_create_ah 543 512 -31
ib_uverbs_create_srq 662 630 -32
ib_uverbs_reg_mr 737 699 -38
ib_uverbs_create_cq 639 600 -39
ib_uverbs_alloc_pd 485 446 -39
ib_uverbs_create_qp 1020 979 -41
Signed-off-by: Roland Dreier <rolandd@cisco.com>
In error paths when destroying an object, uverbs should not decrement
associated objects' usecnt, since ib_dereg_mr(), ib_destroy_qp(),
etc. already do that.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If ibdev->alloc_ucontext() fails then ib_uverbs_get_context() does not
unlock file->mutex before returning error.
Signed-off by: Ganapathi CH <cganapathi@novell.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The old code incorrectly used the primary P_Key index as the alternate
index too.
Signed-off-by: Ami Perlmutter <amip@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The old code didn't convert from the kernel's enum correctly.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Pass actual capacity of created SRQ back to userspace, so that
userspace can report accurate capacities. This requires an ABI bump,
to change struct ib_uverbs_create_srq_resp.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add support to uverbs to handle querying userspace SRQs (shared
receive queues), including adding an ABI for marshalling requests and
responses. The kernel midlayer already has the underlying
ib_query_srq() function.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add support to uverbs to handle querying userspace QPs (queue pairs),
including adding an ABI for marshalling requests and responses. The
kernel midlayer already has the underlying ib_query_qp() function.
Signed-off-by: Dotan Barak <dotanb@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add support to uverbs to handle resizing userspace CQs (completion
queues), including adding an ABI for marshalling requests and
responses. The kernel midlayer already has ib_resize_cq().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
semaphore to mutex conversion by Ingo and Arjan's script.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ Sanity-checked on real IB hardware ]
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add a node_guid field to struct ib_device. It is the responsibility
of the low-level driver to initialize this field before registering a
device with the midlayer. Convert everyone to looking at this field
instead of calling ib_query_device() when all they want is the node
GUID, and remove the node_guid field from struct ib_device_attr.
Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
ib_uverbs_create_cq() should release the completion channel event file
if an error occurs after it looks it up. Also, if userspace asks for
a completion channel and we don't find it, an error should be returned
instead of silently creating a CQ without a completion channel.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If an operation fails after incrementing an object's reference count,
then it should decrement the reference count on the error path.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
uverbs needs to track which multicast groups is each qp
attached to, in order to properly detach when cleanup
is performed on device file close.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Move the computation of QP capabilities (max scatter/gather entries,
max inline data, etc) into the kernel, and have the uverbs module
return the values as part of the create QP response. This keeps
precise knowledge of device limits in the low-level kernel driver.
This requires an ABI bump, so while we're making changes, get rid of
the max_sge parameter for the modify SRQ command -- it's not used and
shouldn't be there.
Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland 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: Roland 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: Roland 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: Roland Dreier <rolandd@cisco.com>
Reject userspace memory registrations with invalid permission flags:
"local write" is required if "remote write" or "remote atomic" is also
requested.
Pointed out by Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
By waiting to add resources to our lists until after the last
operation that can fail, we don't have to remove them from their lists
in the error path. Also, we should hold the idr mutex until we know
whether resource creation has succeed or failed, to avoid someone
finding a resource in our table before we're ready.
Loosely based on work by Robert Walsh <rjwalsh@pathscale.com>.
Signed-off-by: Roland 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: Roland 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: Roland 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: Roland 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: Roland 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: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
