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Add a new IB_WR_SEND_WITH_INV send opcode that can be used to mark a
"send with invalidate" work request as defined in the iWARP verbs and
the InfiniBand base memory management extensions. Also put "imm_data"
and a new "invalidate_rkey" member in a new "ex" union in struct
ib_send_wr. The invalidate_rkey member can be used to pass in an
R_Key/STag to be invalidated. Add this new union to struct
ib_uverbs_send_wr. Add code to copy the invalidate_rkey field in
ib_uverbs_post_send().
Fix up low-level drivers to deal with the change to struct ib_send_wr,
and just remove the imm_data initialization from net/sunrpc/xprtrdma/,
since that code never does any send with immediate operations.
Also, move the existing IB_DEVICE_SEND_W_INV flag to a new bit, since
the iWARP drivers currently in the tree set the bit. The amso1100
driver at least will silently fail to honor the IB_SEND_INVALIDATE bit
if passed in as part of userspace send requests (since it does not
implement kernel bypass work request queueing). Remove the flag from
all existing drivers that set it until we know which ones are OK.
The values chosen for the new flag is not consecutive to avoid clashing
with flags defined in the XRC patches, which are not merged yet but
which are already in use and are likely to be merged soon.
This resurrects a patch sent long ago by Mikkel Hagen <mhagen@iol.unh.edu>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Add a create_flags member to struct ib_qp_init_attr that will allow a
kernel verbs consumer to create a pass special flags when creating a QP.
Add a flag value for telling low-level drivers that a QP will be used
for IPoIB UD LSO. The create_flags member will also be useful for XRC
and ehca low-latency QP support.
Since no create_flags handling is implemented yet, add code to all
low-level drivers to return -EINVAL if create_flags is non-zero.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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In mthca_alloc_icm_table(), the number of entries to allocate for the
table->icm array is computed by calculating obj_size * nobj and then
dividing by MTHCA_TABLE_CHUNK_SIZE. If nobj is really large, then
obj_size * nobj may overflow and the division may get the wrong value
(even a negative value). Fix this by calculating the number of
objects per chunk and then dividing nobj by this value instead.
This patch allows crazy configurations such as loading ib_mthca with
the module parameter num_mtt=33554432 to work properly.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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mthca_make_profile() returns the size in bytes of the HCA context
layout it creates, or a negative value if an error occurs. However,
the return value is declared as u64 and the memfree initialization
path casts this value to int to test if it is negative. This makes it
think incorrectly than an error has occurred if the context size
happens to be bigger than 2GB, since this turns into a negative int.
Fix this by having mthca_make_profile() return an s64 and testing
for an error by checking whether this 64-bit value itself is negative.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Arbel and Sinai devices support checksum generation and verification
of TCP and UDP packets for UD IPoIB messages. This patch checks if
the HCA supports this and sets the IB_DEVICE_UD_IP_CSUM capability
flag if it does. It implements support for handling the IB_SEND_IP_CSUM
send flag and setting the csum_ok field in receive work completions.
Signed-off-by: Eli Cohen <eli@mellnaox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Fix a few whitespace and other coding style problems.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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When mthca_fmr_alloc() returns an error, it should free the MPT at the
index key, not mr->ibmr.lkey, since the lkey has been mangled by
hw_index_to_key() and no longer is the real index. This bug causes
corruption of the MPT table free bitmap when mthca_fmr_alloc() fails.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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replace:
big_endian_variable = cpu_to_beX(beX_to_cpu(big_endian_variable) +
expression_in_cpu_byteorder);
with:
beX_add_cpu(&big_endian_variable, expression_in_cpu_byteorder);
Generated with a semantic patch.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Usually harmless, since the scatterlist is always hard-coded to a length
of 1, but it triggers a BUG() if CONFIG_DEBUG_SG=y, so we better fix it.
This fixes <http://bugzilla.kernel.org/show_bug.cgi?id=9934>.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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If the allocation of the MTT or the mailbox failed, mthca_fmr_alloc()
would return 0 (success) no matter what. This leads to crashes a
little down the road, when we try to dereference eg mr->mtt, which was
really ERR_PTR(-Ewhatever).
Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Signed-off-by: Roland Dreier <rolandd@cisco.com>
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We have recently discovered that Tavor mode requires each WQE in a
posted list of receive WQEs to have a valid NDA field at all times.
This requirement holds true for regular QPs as well as for SRQs. This
patch prelinks the receive queue in a regular QP and keeps the free
list in SRQ always properly linked.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Reviewed-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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The SRQ receive posting functions make sure that srq->first_free never
becomes negative, so we can remove tests of whether it is negative.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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For memfree devices, the firmware QUERY_ADAPTER command does not
return vendor_id, device_id, and revision_id; do not return these
fields in the QUERY_ADAPTER function for memfree devices.
Instead, for memfree devices, initialize the rev_id field of the mthca
device via init_node_data (MAD IFC query), as is done in the
query_device verb implementation.
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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In mthca_reg_phys_mr(), we calculate the page size for the HCA
hardware to use to map the buffer list passed in by the consumer.
For example, if the consumer passes in
[0] addr 0x1000, size 0x1000
[1] addr 0x2000, size 0x1000
then the algorithm would come up with a page size of 0x2000 and a list
of two pages, at 0x0000 and 0x2000. Usually, this would work fine
since the memory region would start at an offset of 0x1000 and have a
length of 0x2000.
However, the old code did not take into account the alignment of the
IO virtual address passed in. For example, if the consumer passed in
a virtual address of 0x6000 for the above, then the offset of 0x1000
would not be used correctly because the page mask of 0x1fff would
result in an offset of 0.
We can fix this quite neatly by making sure that the page shift we use
is no bigger than the first bit where the start of the first buffer
and the IO virtual address differ. Also, we can further simplify the
code by removing the special case for a single buffer by noticing that
it doesn't matter if we use a page size that is too big. This allows
the loop to compute the page shift to be replaced with __ffs().
Thanks to Bryan S Rosenburg <rosnbrg@us.ibm.com> for pointing out the
original bug and suggesting several ways to improve this patch.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Remove MSI support from the mthca driver, as scheduled. There is no
reason to use MSI instead of MSI-X, since MSI-X performs better. No
one has spoken up since MSI support was deprecated in commit f6be6fbe
("IB/mthca: Schedule MSI support for removal"), so apparently the MSI
support is unused.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Most drivers need to set length and offset as well, so may as well fold
those three lines into one.
Add sg_assign_page() for those two locations that only needed to set
the page, where the offset/length is set outside of the function context.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
mlx4_core: Increase command timeout for INIT_HCA to 10 seconds
IPoIB/cm: Use common CQ for CM send completions
IB/uverbs: Fix checking of userspace object ownership
IB/mlx4: Sanity check userspace send queue sizes
IPoIB: Rewrite "if (!likely(...))" as "if (unlikely(!(...)))"
IB/ehca: Enable large page MRs by default
IB/ehca: Change meaning of hca_cap_mr_pgsize
IB/ehca: Fix ehca_encode_hwpage_size() and alloc_fmr()
IB/ehca: Fix masking error in {,re}reg_phys_mr()
IB/ehca: Supply QP token for SRQ base QPs
IPoIB: Use round_jiffies() for ah_reap_task
RDMA/cma: Fix deadlock destroying listen requests
RDMA/cma: Add locking around QP accesses
IB/mthca: Avoid alignment traps when writing doorbells
mlx4_core: Kill mlx4_write64_raw()
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Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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Architectures such as ia64 see alignment traps when doing a 64-bit
read from __be32 doorbell[2] arrays to do doorbell writes in
mthca_write64(). Fix this by just passing the two halves of the
doorbell value into mthca_write64(). This actually improves the
generated code by allowing the compiler to see what's going on better.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Firmware commands are sent to the HCA by writing multiple words to a
command register block. Access to this block of registers is
serialized with a mutex. However, on large SGI systems, problems were
seen with multiple CPUs issuing FW commands at the same time, because
the writes to the register block may be reordered within the system
interconnect and reach the HCA in a different order than they were
issued (even with the mutex). Fix this by adding an mmiowb() before
dropping the mutex.
Tested-by: Arthur Kepner <akepner@sgi.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Increase the number of QPs allowed per multicast group from 8 to 56.
This allows for one QP per core on 16-core systems, which are now
quite common, and allows some space for future growth.
This is basically the same patch that Jack Morgenstein
<jackm@dev.mellanox.co.il> just supplied for mlx4.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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These driver changes incorporate the proposed PCI-X / PCI-Express read
byte count interface. Reading and setting those values doesn't take
place "manually", instead wrapping functions are called to allow
quirks for some PCI bridges.
Signed-off by: Peter Oruba <peter.oruba@amd.com>
Based on work by Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Recover from MSI-X errors by automatically falling back on regular
interrupt, instead of asking the user to do this manually. This makes
it possible to enable MSI-X by default, and will make it possible to
get rid of the msi_x module option in the future.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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The FW command token is currently only updated on a command completion
event. This means that on command timeout, the same token will be
reused for new command, which results in a mess if the timed out
command *does* eventually complete.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Current code sets size0 to 0 at the start of work request posting
functions and then handles size0 == 0 specially within the loop over
work requests. Change this so size0 is set along with f0 the first
time through the loop (when nreq == 0). This makes the code easier to
understand by making it clearer that f0 and size0 are always
initialized if nreq != 0 without having to know that size0 == 0
implies nreq == 0.
Also annotate size0 with uninitialized_var() so that this doesn't
introduce a new compiler warning.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Factor code to set UD entries out of the work request posting
functions into inline functions set_tavor_ud_seg() and
set_arbel_ud_seg(). This doesn't change the generated code in any
significant way, and makes the source easier on the eyes.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Factor code to set remote address and atomic segment entries out of the
work request posting functions into inline functions set_raddr_seg()
and set_atomic_seg(). This doesn't change the generated code in any
significant way, and makes the source easier on the eyes.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Factor code to set data segment entries out of the work request
posting functions into inline functions mthca_set_data_seg() and
mthca_set_data_seg_inval(). This makes the code more readable and
also allows the compiler to do a better job -- on x86_64:
add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-69 (-69)
function old new delta
mthca_arbel_post_srq_recv 373 369 -4
mthca_arbel_post_receive 570 562 -8
mthca_tavor_post_srq_recv 520 508 -12
mthca_tavor_post_send 1344 1330 -14
mthca_arbel_post_send 1481 1467 -14
mthca_tavor_post_receive 792 775 -17
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Commit 9db48926 ("drivers/infiniband/hw/mthca/mthca_qp: kill uninit'd
var warning") added "= 0" to the declarations of f0 to shut up gcc
warnings. However, there's no point in making the code bigger by
initializing f0 to a random value just to get rid of a warning;
setting f0 to 0 is no safer than just using uninitialized_var(), which
documents the situation better and gives smaller code too. For example,
on x86_64:
add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-16 (-16)
function old new delta
mthca_tavor_post_send 1352 1344 -8
mthca_arbel_post_send 1489 1481 -8
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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When warning about out-of-date firmware, current mthca code messes up
the formatting of the version if the subminor doesn't have three
digits. It doesn't fill the field with 0s so we end up with:
ib_mthca 0000:0b:00.0: HCA FW version 1.1. 0 is old (1.2. 0 is current).
Change the format from "%3d" to "%03d" to get the right thing printed.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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The mthca driver supports both MSI and MSI-X. However, MSI-X works with
all hardware that the driver handles, and provides a superset of what
MSI does, so there's no point in having code for both. Schedule MSI
support for removal in 2008 to give anyone who actually needs MSI and
who can't use MSI time to speak up.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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drivers/infiniband/hw/mthca/mthca_qp.c: In function
‘mthca_tavor_post_send’:
drivers/infiniband/hw/mthca/mthca_qp.c:1594: warning: ‘f0’ may be used
uninitialized in this function
drivers/infiniband/hw/mthca/mthca_qp.c: In function
‘mthca_arbel_post_send’:
drivers/infiniband/hw/mthca/mthca_qp.c:1949: warning: ‘f0’ may be used
uninitialized in this function
Initializing 'f0' is not strictly necessary in either case, AFAICS.
I was considering use of uninitialized_var(), but looking at the
complex flow of control in each function, I feel it is wiser and
safer to simply zero the var and be certain of ourselves.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Signed-off-by: Shani Moideen <shani.moideen@wipro.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
----
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Change Kconfig objects from "menu, config" into "menuconfig" so
that the user can disable the whole feature without having to
enter the menu first.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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s/signifant/significant/
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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mthca_free_err_wqe() currently treats both send and receive CQEs
identically if a QP is using an SRQ. But for Tavor hardware, send
CQEs with error can be chained together even if the RQ is part of SRQ,
so we may miss some CQEs.
Fix by following the WQE chain for all send CQEs even for non-SRQ QPs.
This fixes crashes in IPoIB CM:
<https://bugs.openfabrics.org//show_bug.cgi?id=604>
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
IB/cm: Improve local id allocation
IPoIB/cm: Fix SRQ WR leak
IB/ipoib: Fix typos in error messages
IB/mlx4: Check if SRQ is full when posting receive
IB/mlx4: Pass send queue sizes from userspace to kernel
IB/mlx4: Fix check of opcode in mlx4_ib_post_send()
mlx4_core: Fix array overrun in dump_dev_cap_flags()
IB/mlx4: Fix RESET to RESET and RESET to ERROR transitions
IB/mthca: Fix RESET to ERROR transition
IB/mlx4: Set GRH:HopLimit when sending globally routed MADs
IB/mthca: Set GRH:HopLimit when building MLX headers
IB/mlx4: Fix check of max_qp_dest_rdma in modify QP
IB/mthca: Fix use-after-free on device restart
IB/ehca: Return proper error code if register_mr fails
IPoIB: Handle P_Key table reordering
IB/core: Use start_port() and end_port()
IB/core: Add helpers for uncached GID and P_Key searches
IB/ipath: Fix potential deadlock with multicast spinlocks
IB/core: Free umem when mm is already gone
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First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.
This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
getting them indirectly
Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
they don't need sched.h
b) sched.h stops being dependency for significant number of files:
on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
after patch it's only 3744 (-8.3%).
Cross-compile tested on
all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
alpha alpha-up
arm
i386 i386-up i386-defconfig i386-allnoconfig
ia64 ia64-up
m68k
mips
parisc parisc-up
powerpc powerpc-up
s390 s390-up
sparc sparc-up
sparc64 sparc64-up
um-x86_64
x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig
as well as my two usual configs.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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According to the IB spec, a QP can be moved from RESET to the ERROR
state, but mthca firmware does not support this and returns an error if
we try. Work around this FW limitation by moving the QP from RESET to
INIT with dummy parameters and then transitioning from INIT to ERROR.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Global CM packets used by rmda_cm were being sent with a GRH:hopLimit
of zero, causing them to be dropped by the router. The problem is a
missing initialization of the hop_limit field in mthca_read_ah(),
which was called by build_mlx_header() when sending a MAD on QP1.
Signed-off-by: Rolf Manderscheid <rvm@obsidianresearch.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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mthca_cq_clean() updates the CQ consumer index without moving CQEs
back to HW ownership. As a result, the same WRID might get reported
twice, resulting in a use-after-free. This was observed in IPoIB CM.
Fix by moving all freed CQEs to HW ownership.
This fixes <https://bugs.openfabrics.org/show_bug.cgi?id=617>
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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Fix posting lists of > 255 receive WRs for Tavor: rq.next_ind must
be updated each doorbell, otherwise the next doorbell will use an
incorrect index.
Found by Ronni Zimmermann at Mellanox.
Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
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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>
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master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband:
IPoIB: Convert to NAPI
IB: Return "maybe missed event" hint from ib_req_notify_cq()
IB: Add CQ comp_vector support
IB/ipath: Fix a race condition when generating ACKs
IB/ipath: Fix two more spin lock problems
IB/fmr_pool: Add prefix to all printks
IB/srp: Set proc_name
IB/srp: Add orig_dgid sysfs attribute to scsi_host
IPoIB/cm: Don't crash if remote side uses one QP for both directions
RDMA/cxgb3: Support for new abort logic
RDMA/cxgb3: Initialize cpu_idx field in cpl_close_listserv_req message
RDMA/cxgb3: Fail qp creation if the requested max_inline is too large
RDMA/cxgb3: Fix TERM codes
IPoIB/cm: Fix error handling in ipoib_cm_dev_open()
IB/ipath: Don't corrupt pending mmap list when unmapped objects are freed
IB/mthca: Work around kernel QP starvation
IB/ipath: Don't put QP in timeout queue if waiting to send
IB/ipath: Don't call spin_lock_irq() from interrupt context
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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>
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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>
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