Commit Graph

29 Commits

Author SHA1 Message Date
Jason Gunthorpe 540cd69209 RDMA/uverbs: Use UVERBS_ATTR_MIN_SIZE correctly and uniformly
This newer macro allows specifying a lower bound on the accepted size, and
has an 'unlimited' upper bound. Due to this it never checks for trailing
zeroing so it doesn't make any sense to combine it with MIN_SZ_OR_ZERO, so
drop MIN_SZ_OR_ZERO when they are used together

There were a couple of places that open coded this pattern, switch them to
use the clearer UVERBS_ATTR_MIN_SIZE for clarity.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe 83bb444233 RDMA/uverbs: Remove UA_FLAGS
This bit of boilerplate isn't really necessary, we can use bitfields
instead of a flags enum and the macros can then individually initialize
them through the __VA_ARGS__ like everything else.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe 9a119cd597 RDMA/uverbs: Get rid of the & in method specifications
Hide it inside the macros. The & is confusing and interferes with using
this as a generic DSL in later patches.

Since this also touches almost every line, also run the specs through
clang-format (with 'BinPackParameters: false') to make the maintenance
easier.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe 6c61d2a55c RDMA/uverbs: Simplify UVERBS_OBJECT and _TREE family of macros
Instead of the large set of indirecting macros, define the few needed
macros to directly instantiate the struct uverbs_oject_tree_def and
associated objects list.

This is small amount of code duplication but the readability is far
better.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe 595c7736d4 RDMA/uverbs: Simplify method definition macros
Instead of the large set of indirecting macros, define the few needed
macros to directly instantiate the struct uverbs_method_def and associated
attributes list.

This is small amount of code duplication but the readability is far
better.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe d108dac080 RDMA/uverbs: Simplify UVERBS_ATTR family of macros
Instead of using a complex cascade of macros, just directly provide the
initializer list each of the declarations is trying to create.

Now that the macros are simplified this also reworks the uverbs_attr_spec
to be friendly to older compilers by eliminating any unnamed
structures/unions inside, and removing the duplication of some fields. The
structure size remains at 16 bytes which was the original motivation for
some of this oddness.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
2018-07-04 13:47:01 -06:00
Jason Gunthorpe 321d7863ac IB/uverbs: Delete type and id from uverbs_obj_attr
In this context the uobject is not allowed to be NULL, so type is the same
as uobject->type, and at least for IDR, id is the same as uobject->id.

FD objects should never handle the FD number outside the uAPI boundary
code.

Suggested-by: Guy Levi <guyle@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-22 09:02:59 -06:00
Matan Barak 2d9c1bd7e1 IB/uverbs: Add a macro to define a type with no kernel known size
Sometimes the uverbs uAPI  doesn't really care about the structure it gets
from user-space. All it wants to do is to allocate enough space and send
it to the hardware/provider driver. Adding a UVERBS_ATTR_MIN_SIZE that
could be used for this scenarios. We use USHRT_MAX as the kernel known
size to bypass any zero validations.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-19 10:53:02 -06:00
Matan Barak 8762d149e8 IB/uverbs: Add PTR_IN attributes that are allocated/copied automatically
Adding UVERBS_ATTR_SPEC_F_ALLOC_AND_COPY flag to PTR_IN attributes.
By using this flag, the parse automatically allocates and copies the
user-space data. This data is accessible by using uverbs_attr_get_len
and uverbs_attr_get_alloced_ptr inline accessor functions from the
handler.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-19 10:53:02 -06:00
Jason Gunthorpe 0f45e69d62 Verbs flow counters support
This series comes to allow user space applications to monitor real time
 traffic activity and events of the verbs objects it manages, e.g.:
 ibv_qp, ibv_wq, ibv_flow.
 
 This API enables generic counters creation and define mapping
 to association with a verbs object, current mlx5 driver using
 this API for flow counters.
 
 With this API, an application can monitor the entire life cycle of
 object activity, defined here as a static counters attachment.
 This API also allows dynamic counters monitoring of measurement points
 for a partial period in the verbs object life cycle.
 
 In addition it presents the implementation of the generic counters interface.
 
 This will be achieved by extending flow creation by adding a new flow count
 specification type which allows the user to associate a previously created
 flow counters using the generic verbs counters interface to the created flow,
 once associated the user could read statistics by using the read function of
 the generic counters interface.
 
 The API includes:
 1. create and destroyed API of a new counters objects
 2. read the counters values from HW
 
 Note:
 Attaching API to allow application to define the measurement points per objects
 is a user space only API and this data is passed to kernel when the counted
 object (e.g. flow) is created with the counters object.
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Merge tag 'verbs_flow_counters' of git://git.kernel.org/pub/scm/linux/kernel/git/leon/linux-rdma.git into for-next

Pull verbs counters series from Leon Romanovsky:

====================
Verbs flow counters support

This series comes to allow user space applications to monitor real time
traffic activity and events of the verbs objects it manages, e.g.: ibv_qp,
ibv_wq, ibv_flow.

The API enables generic counters creation and define mapping to
association with a verbs object, the current mlx5 driver is using this API
for flow counters.

With this API, an application can monitor the entire life cycle of object
activity, defined here as a static counters attachment.  This API also
allows dynamic counters monitoring of measurement points for a partial
period in the verbs object life cycle.

In addition it presents the implementation of the generic counters
interface.

This will be achieved by extending flow creation by adding a new flow
count specification type which allows the user to associate a previously
created flow counters using the generic verbs counters interface to the
created flow, once associated the user could read statistics by using the
read function of the generic counters interface.

The API includes:
1. create and destroyed API of a new counters objects
2. read the counters values from HW

Note:
Attaching API to allow application to define the measurement points per
objects is a user space only API and this data is passed to kernel when
the counted object (e.g. flow) is created with the counters object.
===================

* tag 'verbs_flow_counters':
  IB/mlx5: Add counters read support
  IB/mlx5: Add flow counters read support
  IB/mlx5: Add flow counters binding support
  IB/mlx5: Add counters create and destroy support
  IB/uverbs: Add support for flow counters
  IB/core: Add support for flow counters
  IB/core: Support passing uhw for create_flow
  IB/uverbs: Add read counters support
  IB/core: Introduce counters read verb
  IB/uverbs: Add create/destroy counters support
  IB/core: Introduce counters object and its create/destroy
  IB/uverbs: Add an ib_uobject getter to ioctl() infrastructure
  net/mlx5: Export flow counter related API
  net/mlx5: Use flow counter pointer as input to the query function
2018-06-04 08:48:11 -06:00
Matan Barak 3efa38125b IB/uverbs: Add an ib_uobject getter to ioctl() infrastructure
Previously, the user had to dig inside the attribute to get the uobject.
Add a helper function that correctly extract it (and do the required
checks) for him/her.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-06-02 07:33:53 +03:00
Jason Gunthorpe f4602cbb0a IB/uverbs: Fix uverbs_attr_get_obj
The err pointer comes from uverbs_attr_get, not from the uobject member,
which does not store an ERR_PTR.

Fixes: be934cca9e ("IB/uverbs: Add device memory registration ioctl support")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
2018-05-23 15:25:53 -06:00
Ariel Levkovich be934cca9e IB/uverbs: Add device memory registration ioctl support
Adding new ioctl method for the MR object - REG_DM_MR.

This command can be used by users to register an allocated
device memory buffer as an MR and receive lkey and rkey
to be used within work requests.

It is added as a new method under the MR object and using a new
ib_device callback - reg_dm_mr.
The command creates a standard ib_mr object which represents the
registered memory.

Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-04-05 11:16:39 -06:00
Matan Barak 494c5580aa IB/uverbs: Add enum attribute type to ioctl() interface
Methods sometimes need to get one attribute out of a group of
pre-defined attributes. This is an enum-like behavior. Since
this is a common requirement, we add a new ENUM attribute to the
generic uverbs ioctl() layer. This attribute is embedded in methods,
like any other attributes we currently have. ENUM attributes point to
an array of standard UVERBS_ATTR_PTR_IN. The user-space encodes the
enum's attribute id in the id field and the internal PTR_IN attr id in
the enum_data.elem_id field. This ENUM attribute could be shared by
several attributes and it can get UVERBS_ATTR_SPEC_F_MANDATORY flag,
stating this attribute must be supported by the kernel, like any other
attribute.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-04-04 12:06:24 -06:00
Matan Barak 41b2a71fc8 IB/uverbs: Move ioctl path of create_cq and destroy_cq to a new file
Currently, all objects are declared in uverbs_std_types. This could lead
to a huge file once we implement all objects, methods and handlers.
Moving each object to its own file to keep the files smaller and more
readable. uverbs_std_types.c will only contain the parsing tree
definition and objects without any methods.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-03-19 14:45:17 -06:00
Matan Barak c66db31113 IB/uverbs: Safely extend existing attributes
Previously, we've used UVERBS_ATTR_SPEC_F_MIN_SZ for extending existing
attributes. The behavior of this flag was the kernel accepts anything
bigger than the minimum size it specified. This is unsafe, since in
order to safely extend an attribute, we need to make sure unknown size
is zeroed. Replacing UVERBS_ATTR_SPEC_F_MIN_SZ with
UVERBS_ATTR_SPEC_F_MIN_SZ_OR_ZERO, which essentially checks that the
unknown size is zero. In addition, attributes are now decorated with
UVERBS_ATTR_TYPE and UVERBS_ATTR_STRUCT, so we can provide the minimum
and known length.

Users of this flag needs to use copy_from_or_zero functions/macros.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-03-19 14:45:17 -06:00
Matan Barak 1f07e08fab IB/uverbs: Enable compact representation of uverbs_attr_spec
Downstream patches extend uverbs_attr_spec with new fields.
In order to save space, we move the type and flags fields to
the various attribute flavors contained in the union.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-03-19 14:45:17 -06:00
Matan Barak 1f7ff9d5d3 IB/uverbs: Move to new headers and make naming consistent
Use macros to make names consistent in ioctl() uAPI:
The ioctl() uAPI works with object-method hierarchy. The method part
also states which handler should be executed when this method is called
from user-space. Therefore, we need to tie method, method's id, method's
handler and the object owning this method together.
Previously, this was done through explicit developer chosen names.
This makes grepping the code harder. Changing the method's name,
method's handler and object's name to be automatically generated based
on the ids.

The headers are split in a way so they be included and used by
user-space. One header strictly contains structures that are used
directly by user-space applications, where another header is used for
internal library (i.e. libibverbs) to form the ioctl() commands.
Other header simply contains the required general command structure.

Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-03-19 14:45:17 -06:00
Jason Gunthorpe 2f36028ce9 IB/uverbs: Use u64_to_user_ptr() not a union
The union approach will get the endianness wrong sometimes if the kernel's
pointer size is 32 bits resulting in EFAULTs when trying to copy to/from
user.

Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-02-15 14:59:45 -07:00
Matan Barak 89d9e8d3f1 IB/uverbs: Always use the attribute size provided by the user
This fixes several bugs around the copy_to/from user path:
 - copy_to used the user provided size of the attribute
   and could copy data beyond the end of the kernel buffer into
   userspace.
 - copy_from didn't know the size of the kernel buffer and
   could have left kernel memory unexpectedly un-initialized.
 - copy_from did not use the user length to determine if the
   attribute data is inlined or not.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-02-15 14:59:44 -07:00
Matan Barak 5242711294 IB/core: Assign root to all drivers
In order to use the parsing tree, we need to assign the root
to all drivers. Currently, we just assign the default parsing
tree via ib_uverbs_add_one. The driver could override this by
assigning a parsing tree prior to registering the device.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:14 -04:00
Matan Barak d70724f149 IB/core: Add legacy driver's user-data
In this phase, we don't want to change all the drivers to use
flexible driver's specific attributes. Therefore, we add two default
attributes: UHW_IN and UHW_OUT. These attributes are optional in some
methods and they encode the driver specific command data. We add
a function that extract this data and creates the legacy udata over
it.

Driver's data should start from UVERBS_UDATA_DRIVER_DATA_FLAG. This
turns on the first bit of the namespace, indicating this attribute
belongs to the driver's namespace.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:13 -04:00
Matan Barak 3541030650 IB/core: Add macros for declaring methods and attributes
This patch adds macros for declaring objects, methods and
attributes. These definitions are later used by downstream patches
to declare some of the default types.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:11 -04:00
Matan Barak 118620d368 IB/core: Add uverbs merge trees functionality
Different drivers support different features and even subset of the
common uverbs implementation. Currently, this is handled as bitmask
in every driver that represents which kind of methods it supports, but
doesn't go down to attributes granularity. Moreover, drivers might
want to add their specific types, methods and attributes to let
their user-space counter-parts be exposed to some more efficient
abstractions. It means that existence of different features is
validated syntactically via the parsing infrastructure rather than
using a complex in-handler logic.

In order to do that, we allow defining features and abstractions
as parsing trees. These per-feature parsing tree could be merged
to an efficient (perfect-hash based) parsing tree, which is later
used by the parsing infrastructure.

To sum it up, this makes a parse tree unique for a device and
represents only the features this particular device supports.
This is done by having a root specification tree per feature.
Before a device registers itself as an IB device, it merges
all these trees into one parsing tree. This parsing tree
is used to parse all user-space commands.

A future user-space application could read this parse tree. This
tree represents which objects, methods and attributes are
supported by this device.

This is based on the idea of
Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:10 -04:00
Matan Barak 09e3ebf8c1 IB/core: Add DEVICE object and root tree structure
This adds the DEVICE object. This object supports creating the context
that all objects are created from. Moreover, it supports executing
methods which are related to the device itself, such as QUERY_DEVICE.
This is a singleton object (per file instance).

All standard objects are put in the root structure. This root will later
on be used in drivers as the source for their whole parsing tree.
Later on, when new features are added, these drivers could mix this root
with other customized objects.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:10 -04:00
Matan Barak 5009010fbf IB/core: Declare an object instead of declaring only type attributes
Switch all uverbs_type_attrs_xxxx with DECLARE_UVERBS_OBJECT
macros. This will be later used in order to embed the object
specific methods in the objects as well.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:09 -04:00
Matan Barak fac9658cab IB/core: Add new ioctl interface
In this ioctl interface, processing the command starts from
properties of the command and fetching the appropriate user objects
before calling the handler.

Parsing and validation is done according to a specifier declared by
the driver's code. In the driver, all supported objects are declared.
These objects are separated to different object namepsaces. Dividing
objects to namespaces is done at initialization by using the higher
bits of the object ids. This initialization can mix objects declared
in different places to one parsing tree using in this ioctl interface.

For each object we list all supported methods. Similarly to objects,
methods are separated to method namespaces too. Namespacing is done
similarly to the objects case. This could be used in order to add
methods to an existing object.

Each method has a specific handler, which could be either a default
handler or a driver specific handler.
Along with the handler, a bunch of attributes are specified as well.
Similarly to objects and method, attributes are namespaced and hashed
by their ids at initialization too. All supported attributes are
subject to automatic fetching and validation. These attributes include
the command, response and the method's related objects' ids.

When these entities (objects, methods and attributes) are used, the
high bits of the entities ids are used in order to calculate the hash
bucket index. Then, these high bits are masked out in order to have a
zero based index. Since we use these high bits for both bucketing and
namespacing, we get a compact representation and O(1) array access.
This is mandatory for efficient dispatching.

Each attribute has a type (PTR_IN, PTR_OUT, IDR and FD) and a length.
Attributes could be validated through some attributes, like:
(*) Minimum size / Exact size
(*) Fops for FD
(*) Object type for IDR

If an IDR/fd attribute is specified, the kernel also states the object
type and the required access (NEW, WRITE, READ or DESTROY).
All uobject/fd management is done automatically by the infrastructure,
meaning - the infrastructure will fail concurrent commands that at
least one of them requires concurrent access (WRITE/DESTROY),
synchronize actions with device removals (dissociate context events)
and take care of reference counting (increase/decrease) for concurrent
actions invocation. The reference counts on the actual kernel objects
shall be handled by the handlers.

 objects
+--------+
|        |
|        |   methods                                                                +--------+
|        |   ns         method      method_spec                           +-----+   |len     |
+--------+  +------+[d]+-------+   +----------------+[d]+------------+    |attr1+-> |type    |
| object +> |method+-> | spec  +-> +  attr_buckets  +-> |default_chain+--> +-----+   |idr_type|
+--------+  +------+   |handler|   |                |   +------------+    |attr2|   |access  |
|        |  |      |   +-------+   +----------------+   |driver chain|    +-----+   +--------+
|        |  |      |                                    +------------+
|        |  +------+
|        |
|        |
|        |
|        |
|        |
|        |
|        |
|        |
|        |
|        |
+--------+

[d] = Hash ids to groups using the high order bits

The right types table is also chosen by using the high bits from
the ids. Currently we have either default or driver specific groups.

Once validation and object fetching (or creation) completed, we call
the handler:
int (*handler)(struct ib_device *ib_dev, struct ib_uverbs_file *ufile,
               struct uverbs_attr_bundle *ctx);

ctx bundles attributes of different namespaces. Each element there
is an array of attributes which corresponds to one namespaces of
attributes. For example, in the usually used case:

 ctx                               core
+----------------------------+     +------------+
| core:                      +---> | valid      |
+----------------------------+     | cmd_attr   |
| driver:                    |     +------------+
|----------------------------+--+  | valid      |
                                |  | cmd_attr   |
                                |  +------------+
                                |  | valid      |
                                |  | obj_attr   |
                                |  +------------+
                                |
                                |  drivers
                                |  +------------+
                                +> | valid      |
                                   | cmd_attr   |
                                   +------------+
                                   | valid      |
                                   | cmd_attr   |
                                   +------------+
                                   | valid      |
                                   | obj_attr   |
                                   +------------+

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-31 08:35:09 -04:00
Matan Barak f43dbebfa3 IB/core: Add support to finalize objects in one transaction
The new ioctl based infrastructure either commits or rollbacks
all objects of the method as one transaction. In order to do
that, we introduce a notion of dealing with a collection of
objects that are related to a specific method.

This also requires adding a notion of a method and attribute.
A method contains a hash of attributes, where each bucket
contains several attributes. The attributes are hashed according
to their namespace which resides in the four upper bits of the id.

For example, an object could be a CQ, which has an action of CREATE_CQ.
This action has multiple attributes. For example, the CQ's new handle
and the comp_channel. Each layer in this hierarchy - objects, methods
and attributes is split into namespaces. The basic example for that is
one namespace representing the default entities and another one
representing the driver specific entities.

When declaring these methods and attributes, we actually declare
their specifications. When a method is executed, we actually
allocates some space to hold auxiliary information. This auxiliary
information contains meta-data about the required objects, such
as pointers to their type information, pointers to the uobjects
themselves (if exist), etc.
The specification, along with the auxiliary information we allocated
and filled is given to the finalize_objects function.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-30 10:30:38 -04:00
Matan Barak a0aa309c39 IB/core: Add a generic way to execute an operation on a uobject
The ioctl infrastructure treats all user-objects in the same manner.
It gets objects ids from the user-space and by using the object type
and type attributes mentioned in the object specification, it executes
this required method. Passing an object id from the user-space as
an attribute is carried out in three stages. The first is carried out
before the actual handler and the last is carried out afterwards.

The different supported operations are read, write, destroy and create.
In the first stage, the former three actions just fetches the object
from the repository (by using its id) and locks it. The last action
allocates a new uobject. Afterwards, the second stage is carried out
when the handler itself carries out the required modification of the
object. The last stage is carried out after the handler finishes and
commits the result. The former two operations just unlock the object.
Destroy calls the "free object" operation, taking into account the
object's type and releases the uobject as well. Creation just adds the
new uobject to the repository, making the object visible to the
application.

In order to abstract these details from the ioctl infrastructure
layer, we add uverbs_get_uobject_from_context and
uverbs_finalize_object functions which corresponds to the first
and last stages respectively.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Reviewed-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-08-30 10:30:38 -04:00