Commit Graph

12 Commits

Author SHA1 Message Date
Joachim Fenkes
51aaa54eb9 IB/ehca: Fix static rate calculation
The IPD (inter-packet delay) formula was a little off and assumed a
fixed physical link rate; fix the formula and query the actual
physical link rate, now that we can get it.  Also, refactor the
calculation into a common function ehca_calc_ipd() and use that
instead of duplicating code.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-11-13 15:27:00 -08:00
Hoang-Nam Nguyen
2b94397adc IB/ehca: Fix warnings issued by checkpatch.pl
Run the existing ehca code through checkpatch.pl and clean up the
worst of the coding style violations.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-07-17 18:37:40 -07:00
Joachim Fenkes
8705ce5b90 IB/ehca: Notify consumers of LID/PKEY/SM changes after nondisruptive events
When firmware reports a nondisruptive port configuration change event,
previous versions of the eHCA driver didn't forward the event to consumers
like IPoIB.  Add code that determines the type of configuration change by
comparing old and new port attributes and reports it.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-07-09 20:12:27 -07:00
Joachim Fenkes
a6a12947fb IB/ehca: add Shared Receive Queue support
Support SRQs on eHCA2. Since an SRQ is a QP for eHCA2, a lot of code
(structures, create, destroy, post_recv) can be shared between QP and SRQ.

Signed-off-by: Joachim Fenkes <fenkes@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-07-09 20:12:27 -07:00
Roland Dreier
f7c6a7b5d5 IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules
Export ib_umem_get()/ib_umem_release() and put low-level drivers in
control of when to call ib_umem_get() to pin and DMA map userspace,
rather than always calling it in ib_uverbs_reg_mr() before calling the
low-level driver's reg_user_mr method.

Also move these functions to be in the ib_core module instead of
ib_uverbs, so that driver modules using them do not depend on
ib_uverbs.

This has a number of advantages:
 - It is better design from the standpoint of making generic code a
   library that can be used or overridden by device-specific code as
   the details of specific devices dictate.
 - Drivers that do not need to pin userspace memory regions do not
   need to take the performance hit of calling ib_mem_get().  For
   example, although I have not tried to implement it in this patch,
   the ipath driver should be able to avoid pinning memory and just
   use copy_{to,from}_user() to access userspace memory regions.
 - Buffers that need special mapping treatment can be identified by
   the low-level driver.  For example, it may be possible to solve
   some Altix-specific memory ordering issues with mthca CQs in
   userspace by mapping CQ buffers with extra flags.
 - Drivers that need to pin and DMA map userspace memory for things
   other than memory regions can use ib_umem_get() directly, instead
   of hacks using extra parameters to their reg_phys_mr method.  For
   example, the mlx4 driver that is pending being merged needs to pin
   and DMA map QP and CQ buffers, but it does not need to create a
   memory key for these buffers.  So the cleanest solution is for mlx4
   to call ib_umem_get() in the create_qp and create_cq methods.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-08 18:00:37 -07:00
Roland Dreier
ed23a72778 IB: Return "maybe missed event" hint from ib_req_notify_cq()
The semantics defined by the InfiniBand specification say that
completion events are only generated when a completions is added to a
completion queue (CQ) after completion notification is requested.  In
other words, this means that the following race is possible:

	while (CQ is not empty)
		ib_poll_cq(CQ);
	// new completion is added after while loop is exited
	ib_req_notify_cq(CQ);
	// no event is generated for the existing completion

To close this race, the IB spec recommends doing another poll of the
CQ after requesting notification.

However, it is not always possible to arrange code this way (for
example, we have found that NAPI for IPoIB cannot poll after
requesting notification).  Also, some hardware (eg Mellanox HCAs)
actually will generate an event for completions added before the call
to ib_req_notify_cq() -- which is allowed by the spec, since there's
no way for any upper-layer consumer to know exactly when a completion
was really added -- so the extra poll of the CQ is just a waste.

Motivated by this, we add a new flag "IB_CQ_REPORT_MISSED_EVENTS" for
ib_req_notify_cq() so that it can return a hint about whether the a
completion may have been added before the request for notification.
The return value of ib_req_notify_cq() is extended so:

	 < 0	means an error occurred while requesting notification
	== 0	means notification was requested successfully, and if
		IB_CQ_REPORT_MISSED_EVENTS was passed in, then no
		events were missed and it is safe to wait for another
		event.
	 > 0	is only returned if IB_CQ_REPORT_MISSED_EVENTS was
		passed in.  It means that the consumer must poll the
		CQ again to make sure it is empty to avoid the race
		described above.

We add a flag to enable this behavior rather than turning it on
unconditionally, because checking for missed events may incur
significant overhead for some low-level drivers, and consumers that
don't care about the results of this test shouldn't be forced to pay
for the test.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-06 21:18:11 -07:00
Michael S. Tsirkin
f4fd0b224d IB: Add CQ comp_vector support
Add a num_comp_vectors member to struct ib_device and extend
ib_create_cq() to pass in a comp_vector parameter -- this parallels
the userspace libibverbs API.  Update all hardware drivers to set
num_comp_vectors to 1 and have all ULPs pass 0 for the comp_vector
value.  Pass the value of num_comp_vectors to userspace rather than
hard-coding a value of 1.

We want multiple CQ event vector support (via MSI-X or similar for
adapters that can generate multiple interrupts), but it's not clear
how many vectors we want, or how we want to deal with policy issues
such as how to decide which vector to use or how to set up interrupt
affinity.  This patch is useful for experimenting, since no core
changes will be necessary when updating a driver to support multiple
vectors, and we know that we want to make at least these changes
anyway.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-05-06 21:18:11 -07:00
Hoang-Nam Nguyen
4c34bdf58c IB/ehca: Remove use of do_mmap()
This patch removes do_mmap() from ehca:
 - Call remap_pfn_range() for hardware register block
 - Use vm_insert_page() to register memory allocated for completion
   queues and queue pairs
 - The actual mmap() call/trigger is now controlled by user space,
   ie. libehca

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-02-04 14:11:57 -08:00
Hoang-Nam Nguyen
f2d9136133 IB/ehca: Use proper GFP_ flags for get_zeroed_page()
Here is a patch for ehca to use proper flag, ie. GFP_ATOMIC
resp. GFP_KERNEL, when calling get_zeroed_page() to prevent "Bug:
scheduling while atomic...". This error does not cause a kernel panic
but makes ipoib un-usable afterwards.  It is reproducible on
2.6.20-rc4 if one does ifconfig down during a flood ping test.  I have
not observed this error in earlier releases incl. 2.6.20-rc1.

This error occurs when a qp event/irq is received and ehca event
handler allocates a control block/page to obtain HCA error data block.
Use of GFP_ATOMIC when in interrupt context prevents this issue.

Signed-off-by Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-01-09 14:14:24 -08:00
Hoang-Nam Nguyen
7e28db5d8f IB/ehca: Assure 4K alignment for firmware control blocks
Assure 4K alignment for firmware control blocks in 64K page mode,
because kzalloc()'s result address might not be 4K aligned if 64K
pages are enabled. Thus, we introduce wrappers called
ehca_{alloc,free}_fw_ctrlblock(), which use a slab cache for objects
with 4K length and 4K alignment in order to alloc/free firmware
control blocks in 64K page mode. In 4K page mode those wrappers just
are defines of get_zeroed_page() and free_page().

Signed-off-by: Hoang-Nam Nguyen <hnguyen@de.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-11-09 12:41:57 -08:00
Ralph Campbell
9bc57e2d19 IB/uverbs: Pass userspace data to modify_srq and modify_qp methods
Pass a struct ib_udata to the low-level driver's ->modify_srq() and
->modify_qp() methods, so that it can get to the device-specific data
passed in by the userspace driver.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-09-22 15:22:25 -07:00
Heiko J Schick
fab97220c9 IB/ehca: Add driver for IBM eHCA InfiniBand adapters
Add a driver for IBM GX bus InfiniBand adapters, which are usable with
some pSeries/System p systems.

Signed-off-by: Heiko J Schick <schickhj.ibm.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-09-22 15:22:22 -07:00