linux/drivers/infiniband/core
Igor Ivanov 400dbc9658 IB/core: Infrastructure for extensible uverbs commands
Add infrastructure to support extended uverbs capabilities in a
forward/backward manner.  Uverbs command opcodes which are based on
the verbs extensions approach should be greater or equal to
IB_USER_VERBS_CMD_THRESHOLD.  They have new header format and
processed a bit differently.

Whenever a specific IB_USER_VERBS_CMD_XXX is extended, which practically means
it needs to have additional arguments, we will be able to add them without creating
a completely new IB_USER_VERBS_CMD_YYY command or bumping the uverbs ABI version.

This patch for itself doesn't provide the whole scheme which is also dependent
on adding a comp_mask field to each extended uverbs command struct.

The new header framework allows for future extension of the CMD arguments
(ib_uverbs_cmd_hdr.in_words, ib_uverbs_cmd_hdr.out_words) for an existing
new command (that is a command that supports the new uverbs command header format
suggested in this patch) w/o bumping ABI version and with maintaining backward
and formward compatibility to new and old libibverbs versions.

In the uverbs command we are passing both uverbs arguments and the provider arguments.
We split the ib_uverbs_cmd_hdr.in_words to ib_uverbs_cmd_hdr.in_words which will now carry only
uverbs input argument struct size and  ib_uverbs_cmd_hdr.provider_in_words that will carry
the provider input argument size. Same goes for the response (the uverbs CMD output argument).

For example take the create_cq call and the mlx4_ib provider:

The uverbs layer gets libibverb's struct ibv_create_cq (named struct ib_uverbs_create_cq
in the kernel), mlx4_ib gets libmlx4's struct mlx4_create_cq (which includes struct
ibv_create_cq and is named struct mlx4_ib_create_cq in the kernel) and
in_words = sizeof(mlx4_create_cq)/4 .

Thus ib_uverbs_cmd_hdr.in_words carry both uverbs plus mlx4_ib input argument sizes,
where uverbs assumes it knows the size of its input argument - struct ibv_create_cq.

Now, if we wish to add a variable to struct ibv_create_cq, we can add a comp_mask field
to the struct which is basically bit field indicating which fields exists in the struct
(as done for the libibverbs API extension), but we need a way to tell what is the total
size of the struct and not assume the struct size is predefined (since we may get different
struct sizes from different user libibverbs versions). So we know at which point the
provider input argument (struct mlx4_create_cq) begins. Same goes for extending the
provider struct mlx4_create_cq. Thus we split the ib_uverbs_cmd_hdr.in_words to
ib_uverbs_cmd_hdr.in_words which will now carry only uverbs input argument struct size and
ib_uverbs_cmd_hdr.provider_in_words that will carry the provider (mlx4_ib) input argument size.

Signed-off-by: Igor Ivanov <Igor.Ivanov@itseez.com>
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
2013-08-28 09:52:03 -07:00
..
addr.c IB/addr: Add AF_IB support to ip_addr_size 2013-06-20 13:08:02 -07:00
agent.c
agent.h
cache.c IB/core: Add ib_find_exact_cached_pkey() 2012-09-30 20:33:30 -07:00
cm_msgs.h IB/core: Move CM_xxx_ATTR_ID macros from cm_msgs.h to ib_cm.h 2012-07-08 18:05:06 -07:00
cm.c idr: remove MAX_IDR_MASK and move left MAX_IDR_* into idr.c 2013-02-27 19:10:20 -08:00
cma.c RDMA/cma: Only call cma_save_ib_info() for CM REQs 2013-07-31 00:50:44 -07:00
core_priv.h
device.c IB/core: Handle table with full and partial membership for the same P_Key 2012-09-30 20:33:29 -07:00
fmr_pool.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
iwcm.c RDMA/iwcm: Don't touch cmid after dropping reference 2013-04-24 17:47:33 -07:00
iwcm.h
mad_priv.h
mad_rmpp.c
mad_rmpp.h
mad.c IB/core: Create QP1 using the pkey index which contains the default pkey 2013-07-31 14:15:17 -07:00
Makefile
multicast.c infiniband: add in export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:31:35 -04:00
netlink.c infiniband: pass rdma_cm module to netlink_dump_start 2012-10-07 00:30:56 -04:00
packer.c infiniband: add in export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:31:35 -04:00
sa_query.c IB/sa: Export function to pack a path record into wire format 2013-06-20 23:35:39 -07:00
sa.h
smi.c
smi.h
sysfs.c Main batch of InfiniBand/RDMA changes for 3.11 merge window: 2013-07-13 12:57:21 -07:00
ucm.c IB/core: convert to idr_alloc() 2013-02-27 19:10:16 -08:00
ucma.c RDMA/ucma: Allow user space to specify AF_IB when joining multicast 2013-06-20 23:35:45 -07:00
ud_header.c infiniband: add in export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:31:35 -04:00
umem.c IB/core: Fix mismatch between locked and pinned pages 2012-05-11 11:38:22 -07:00
user_mad.c switch device_get_devnode() and ->devnode() to umode_t * 2012-01-03 22:54:55 -05:00
uverbs_cmd.c IB/uverbs: Use get_unused_fd_flags(O_CLOEXEC) instead of get_unused_fd() 2013-07-08 11:15:45 -07:00
uverbs_main.c IB/core: Infrastructure for extensible uverbs commands 2013-08-28 09:52:03 -07:00
uverbs_marshall.c infiniband: add in export.h for files using EXPORT_SYMBOL/THIS_MODULE 2011-10-31 19:31:35 -04:00
uverbs.h IB/uverbs: Implement memory windows support in uverbs 2013-02-21 11:59:09 -08:00
verbs.c IB/core: Add receive flow steering support 2013-08-28 09:51:52 -07:00