RDMA/core: Postpone uobject cleanup on failure till FD close

Remove the ib_is_destroyable_retryable() concept.

The idea here was to allow the drivers to forcibly clean the HW object
even if they otherwise didn't want to (eg because of usecnt). This was an
attempt to clean up in a world where drivers were not allowed to fail HW
object destruction.

Now that we are going back to allowing HW objects to fail destroy this
doesn't make sense. Instead if a uobject's HW object can't be destroyed it
is left on the uobject list and it is up to uverbs_destroy_ufile_hw() to
clean it. Multiple passes over the uobject list allow hidden dependencies
to be resolved. If that fails the HW driver is broken, throw a WARN_ON and
leak the HW object memory.

All the other tricky failure paths (eg on creation error unwind) have
already been updated to this new model.

Link: https://lore.kernel.org/r/20201104144556.3809085-2-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB: When attrs.udata/ufile is available use that instead of uobject

The ucontext and ufile should not be accessed via the uobject, all these
cases have an attrs so use that instead.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB: Pass uverbs_attr_bundle down ib_x destroy path

The uverbs_attr_bundle with the ucontext is sent down to the drivers ib_x
destroy path as ib_udata. The next patch will use the ib_udata to free the
drivers destroy path from the dependency in 'uobject->context' as we
already did for the create path.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB: Pass uverbs_attr_bundle down uobject destroy path

Pass uverbs_attr_bundle down the uobject destroy path. The next patch will
use this to eliminate the dependecy of the drivers in ib_x->uobject
pointers.

Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/uverbs: Allow the compiler to verify declaration and definition consistency

This patch avoids that sparse reports the following warnings:

drivers/infiniband/core/uverbs_std_types_flow_action.c:442:30: warning: symbol 'uverbs_def_obj_flow_action' was not declared. Should it be static?
drivers/infiniband/core/uverbs_std_types_dm.c:112:30: warning: symbol 'uverbs_def_obj_dm' was not declared. Should it be static?
drivers/infiniband/core/uverbs_std_types_counters.c:153:30: warning: symbol 'uverbs_def_obj_counters' was not declared. Should it be static?
drivers/infiniband/core/uverbs_std_types_mr.c:213:30: warning: symbol 'uverbs_def_obj_mr' was not declared. Should it be static?

Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Fixes: 0bd01f3d0907 ("RDMA/uverbs: Require all objects to have a driver destroy function")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA: Start use ib_device_ops

Make all the required change to start use the ib_device_ops structure.

Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/uverbs: Do not pass ib_uverbs_file to ioctl methods

The uverbs_attr_bundle already contains this pointer, and most methods
don't actually need it. Get rid of the redundant function argument.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

RDMA/uverbs: Require all objects to have a driver destroy function

If we can't destroy the object then we certainly shouldn't allow it be
created or used. Remove it from the uverbs_uapi in this case.

This also disables methods of other objects that have mandatory object
handle inputs - ie REG_DM_MR is now automatically removed if DM objects
cannot be created.

Typically drivers not supporting an interface will mark all of the
supporting functions as NULL, including destroy.

This is intended to automatically eliminate entire corner cases in the API
that are difficult to test.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

IB/uverbs: Do not pass struct ib_device to the ioctl methods

This does the same as the patch before, except for ioctl. The rules are
the same, but for the ioctl methods the core code handles setting up the
uobject.

- Retrieve the ib_dev from the uobject->context->device. This is
safe under ioctl as the core has already done rdma_alloc_begin_uobject
and so CREATE calls are entirely protected by the rwsem.
- Retrieve the ib_dev from uobject->object
- Call ib_uverbs_get_ucontext()

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/uverbs: Fix locking around struct ib_uverbs_file ucontext

We have a parallel unlocked reader and writer with ib_uverbs_get_context()
vs everything else, and nothing guarantees this works properly.

Audit and fix all of the places that access ucontext to use one of the
following locking schemes:
- Call ib_uverbs_get_ucontext() under SRCU and check for failure
- Access the ucontext through an struct ib_uobject context member
while holding a READ or WRITE lock on the uobject.
This value cannot be NULL and has no race.
- Hold the ucontext_lock and check for ufile->ucontext !NULL

This also re-implements ib_uverbs_get_ucontext() in a way that is safe
against concurrent ib_uverbs_get_context() and disassociation.

As a side effect, every access to ucontext in the commands is via
ib_uverbs_get_context() with an error check, or via the uobject, so there
is no longer any need for the core code to check ucontext on every command
call. These checks are also removed.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/uverbs: Tidy up remaining references to ucontext

Unnecessary clutter, to indirect through ucontext when the ufile would do.
Generally most of the code code should only be working with ufile, except
for a few places that touch the driver interface.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

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>

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>

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>

IB: Improve uverbs_cleanup_ucontext algorithm

Improve uverbs_cleanup_ucontext algorithm to work properly when the
topology graph of the objects cannot be determined at compile time. This
is the case with objects created via the devx interface in mlx5.

Typically uverbs objects must be created in a strict topologically sorted
order, so that LIFO ordering will generally cause them to be freed
properly. There are only a few cases (eg memory windows) where objects can
point to things out of the strict LIFO order.

Instead of using an explicit ordering scheme where the HW destroy is not
allowed to fail, go over the list multiple times and allow the destroy
function to fail. If progress halts then a final, desperate, cleanup is
done before leaking the memory. This indicates a driver bug.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/uverbs: Add alloc/free dm uverbs ioctl support

This change adds uverbs support for allocation/freeing
of device memory commands.

A new uverbs object is defined of type idr to represent
and track the new resource type allocation per context.

The API requires provider driver to implement 2 new ib_device
callbacks - one for allocation and one for deallocation which
return and accept (respectively) the ib_dm object which represents
the allocated memory on the device.

The support is added via the ioctl command infrastructure
only.

Signed-off-by: Ariel Levkovich <lariel@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>