These APIs are intended to support drivers that exist outside the usual
driver core probe()/remove() callbacks. Normally the driver core will
prevent remove() from running concurrently with probe(), once this safety
is lost drivers need more support to get the locking and lifetimes right.

ib_unregister_driver() is intended to be used during module_exit of a
driver using these APIs. It unregisters all the associated ib_devices.

ib_unregister_device_and_put() is to be used by a driver-specific removal
function (ie removal by name, removal from a netdev notifier, removal from
netlink)

ib_unregister_queued() is to be used from netdev notifier chains where
RTNL is held.

The locking is tricky here since once things become async it is possible
to race unregister with registration. This is largely solved by relying on
the registration refcount, unregistration will only ever work on something
that has a positive registration refcount - and then an unregistration
mutex serializes all competing unregistrations of the same device.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Several drivers need to find the ib_device from a given netdev. rxe needs
this at speed in an unsleepable context, so choose to implement the
translation using a RCU safe hash table.

The hash table can have a many to one mapping. This is intended to support
some future case where multiple IB drivers (ie iWarp and RoCE) connect to
the same netdevs. driver_ids will need to be different to support this.

In the process this makes the struct ib_device and ib_port_data RCU safe
by deferring their kfrees.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The associated netdev should not actually be very dynamic, so for most
drivers there is no reason for a callback like this. Provide an API to
inform the core code about the net dev affiliation and use a core
maintained data structure instead.

This allows the core code to be more aware of the ndev relationship which
will allow some new APIs based around this.

This also uses locking that makes some kind of sense, many drivers had a
confusing RCU lock, or missing locking which isn't right.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Like the other cases there no real reason to have another array just for
the cache. This larger conversion gets its own patch.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

There is no reason to have three allocations of per-port data. Combine
them together and make the lifetime for all the per-port data match the
struct ib_device.

Following patches will require more port-specific data, now there is a
good place to put it.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

We have many loops iterating over all of the end port numbers on a struct
ib_device, simplify them with a for_each helper.
Reviewed-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

There is no need to expose internals of restrack DB to IB/core.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add ib_ucontext to the uverbs_attr_bundle sent down the iocl and cmd flows
as soon as the flow has ib_uobject.

In addition, remove rdma_get_ucontext helper function that is only used by
ib_umem_get.
Signed-off-by: NShamir Rabinovitch <shamir.rabinovitch@oracle.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The locking here started out with a single lock that covered everything
and then has lately veered into crazy town.

The fundamental problem is that several places need to iterate over a
linked list, but also need to drop their locks to avoid deadlock during
client callbacks.

xarray's restartable iteration offers a simple solution to the
problem. Once all the lists are xarrays we can drop locks in the places
that need that and rely on xarray to provide consistency and locking for
the data structure.

The resulting simplification is that each of the three lists has a
dedicated rwsem that must be held when working with the list it
covers. One data structure is no longer covered by multiple locks.

The sleeping semaphore is selected because the read side generally needs
to be held over something sleeping, and using RCU reader locking in those
cases is overkill.

In the process this simplifies the entire registration/unregistration flow
to be the expected list of setups and the reversed list of matching
teardowns, and the registration lock 'refcount' can now be revised to be
released after the ULPs are removed, providing a very sane semantic for
this feature.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Now that we have a small ID for each client we can use xarray instead of
linearly searching linked lists for client data. This will give much
faster and scalable client data lookup, and will lets us revise the
locking scheme.

Since xarray can store 'going_down' using a mark just entirely eliminate
the struct ib_client_data and directly store the client_data value in the
xarray. However this does require a special iterator as we must still
iterate over any NULL client_data values.

Also eliminate the client_data_lock in favour of internal xarray locking.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This gives each client a unique ID and will let us move client_data to use
xarray, and revise the locking scheme.

clients have to be add/removed in strict FIFO/LIFO order as they
interdepend. To support this the client_ids are assigned to increase in
FIFO order. The existing linked list is kept to support reverse iteration
until xarray can get a reverse iteration API.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>

This really has no purpose anymore, refcount can be used to tell if the
device is still registered. Keeping it around just invites mis-use.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>

The PD allocations in IB/core allows us to simplify drivers and their
error flows in their .alloc_pd() paths. The changes in .alloc_pd() go hand
in had with relevant update in .dealloc_pd().

We will use this opportunity and convert .dealloc_pd() to don't fail, as
it was suggested a long time ago, failures are not happening as we have
never seen a WARN_ON print.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add new macros to be used in drivers while registering ops structure and
IB/core while calling allocation routines, so drivers won't need to
perform kzalloc/kfree in their paths.

The change in allocation stage allows us to initialize common fields prior
to calling to drivers (e.g. restrack).
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Keeping single line wrapper functions is not useful. Hence remove the
ib_sg_dma_address() and ib_sg_dma_len() functions. This patch does not
change any functionality.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Expose XRC ODP capabilities as part of the extended device capabilities.
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Reviewed-by: NMajd Dibbiny <majd@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The ODP support matrix is per operation and per transport. The support for
each transport (RC, UD, etc.) is described with a bit field.

ODP for SRQ WQEs is considered a different kind of support from ODP for RQ
WQs and therefore needs a different capability bit.
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Reviewed-by: NMajd Dibbiny <majd@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

As preparation to hide rdma_restrack_root, refactor the code to use the
ops structure instead of a special callback which is hidden in
rdma_restrack_root.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Drivers that do not provide kernel verbs support should not be used by ib
kernel clients at all.

In case a device does not implement all mandatory verbs for kverbs usage
mark it as a non kverbs provider and prevent its usage for all clients
except for uverbs.

The device is marked as a non kverbs provider using the 'kverbs_provider'
flag which should only be set by the core code.  The clients can choose
whether kverbs are requested for its usage using the 'no_kverbs_req' flag
which is currently set for uverbs only.

This patch allows drivers to remove mandatory verbs stubs and simply set
the callbacks to NULL. The IB device will be registered as a non-kverbs
provider. Note that verbs that are required for the device registration
process must be implemented.
Signed-off-by: NGal Pressman <galpress@amazon.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

All callers to ib_alloc_device() provide a larger size than struct
ib_device and rely on the fact that struct ib_device is embedded in their
driver specific structure as the first member.

Provide a safer variant of ib_alloc_device() that checks and enforces this
approach to make sure the drivers are using it right.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The default behavior of the SCSI core is to set the block layer request
queue parameter max_segment_size to 64 KB. That means that elements of
scatterlists are limited to 64 KB. Since RDMA adapters support larger
sizes, increase max_segment_size for the SRP initiator.

Notes:
- The SCSI max_segment_size parameter was introduced in kernel v5.0. See
  also commit 50c2e910 ("scsi: introduce a max_segment_size
  host_template parameters").
- Some other block drivers already set max_segment_size to UINT_MAX,
  e.g. nbd and rbd.
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

It turns out future patches need this capability quite widely now, not
just for netlink, so provide two global functions to manage the
registration lock refcount.

This also moves the point the lock becomes 1 to within
ib_register_device() so that the semantics of the public API are very sane
and clear. Calling ib_device_try_get() will fail on devices that are only
allocated but not yet registered.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Reviewed-by: NSteve Wise <swise@opengridcomputing.com>
Reviewed-by: NParav Pandit <parav@mellanox.com>

Introduce and use rdma_device_to_ibdev() API for those drivers which are
registering one sysfs group and also use in ib_core.

In subsequent patch, device->provider_ibdev one-to-one mapping is no
longer holds true during accessing sysfs entries.
Therefore, introduce an API rdma_device_to_ibdev() that provides such
information.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Most provider routines are callback routines which ib core invokes.
_callback suffix doesn't convey information about when such callback is
invoked. Therefore, rename port_callback to init_port.

Additionally, store the init_port function pointer in ib_device_ops, so
that it can be accessed in subsequent patches when binding rdma device to
net namespace.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

ib_umem_get() can only be called in a method callback, which always has a
udata parameter. This allows ib_umem_get() to derive the ucontext pointer
directly from the udata without requiring the drivers to find it in some
way or another.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NShamir Rabinovitch <shamir.rabinovitch@oracle.com>

CONFIG_INFINIBAND_ON_DEMAND_PAGING is used in general structures to
micro-optimize the memory footprint. Remove it, so it will allow us to
simplify various ODP device flows.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Introduce a 'flags' field to destroy address handle callback and add a
flag that marks whether the callback is executed in an atomic context or
not.

This will allow drivers to wait for completion instead of polling for it
when it is allowed.
Signed-off-by: NGal Pressman <galpress@amazon.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Introduce a 'flags' field to create address handle callback and add a flag
that marks whether the callback is executed in an atomic context or not.

This will allow drivers to wait for completion instead of polling for it
when it is allowed.
Signed-off-by: NGal Pressman <galpress@amazon.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add new ioctl method for the MR object - ADVISE_MR.

This command can be used by users to give an advice or directions to the
kernel about an address range that belongs to memory regions.

A new ib_device callback, advise_mr(), is introduced here to suupport the
new command. This command takes the following arguments:

- pd:		The protection domain to which all memory regions belong
- advice: 	The type of the advice
	  	* IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH - Pre-fetch a range of
		an on-demand paging MR
	  	* IB_UVERBS_ADVISE_MR_ADVICE_PREFETCH_WRITE - Pre-fetch a range
		of an on-demand paging MR with write intention
- flags:	The properties of the advice
		* IB_UVERBS_ADVISE_MR_FLAG_FLUSH - Operation must end before
		return to the caller
- sg_list:	The list of memory ranges
- num_sge:	The number of memory ranges in the list
- attrs:	More attributes to be parsed by the provider
Signed-off-by: NMoni Shoua <monis@mellanox.com>
Reviewed-by: NGuy Levi <guyle@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Make all the required change to start use the ib_device_ops structure.
Signed-off-by: NKamal Heib <kamalheib1@gmail.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

This change introduces the ib_device_ops structure that defines all the
InfiniBand device operations in one place, so the code will be more
readable and clean, unlike today when the ops are mixed with ib_device
data members.

The providers will need to define the supported operations and assign them
using ib_set_device_ops(), that will also make the providers code more
readable and clean.
Signed-off-by: NKamal Heib <kamalheib1@gmail.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add the new rates that were added to Infiniband spec as part of HDR and 2x
support.
Signed-off-by: NMichael Guralnik <michaelgur@mellanox.com>
Reviewed-by: NMajd Dibbiny <majd@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add the new 2X port width that is part of IB spec 1.3
Signed-off-by: NMichael Guralnik <michaelgur@mellanox.com>
Reviewed-by: NMajd Dibbiny <majd@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

CapabilityMask2 was added in IB Spec 1.3 under PortInfo attribute.  The
new Capapbility mask is needed in order to expose the new 2X width and HDR
speed.
Signed-off-by: NMichael Guralnik <michaelgur@mellanox.com>
Reviewed-by: NMajd Dibbiny <majd@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

Add ability to track allocated ib_ucontext, which are limited
resource and worth to be visible by users.
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

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: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

Now that we can add meta-data to the description of write() methods we
need to pass the uverbs_attr_bundle into all write based handlers so
future patches can use it as a container for any new data transferred out
of the core.

This is the first step to bringing the write() and ioctl() methods to a
common interface signature.

This is a simple search/replace, and we push the attr down into the uobj
and other APIs to keep changes minimal.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

When the rdma device is getting removed, get resource info can race with
device removal, as below:

      CPU-0                                  CPU-1
    --------                               --------
    rdma_nl_rcv_msg()
       nldev_res_get_cq_dumpit()
          mutex_lock(device_lock);
          get device reference
          mutex_unlock(device_lock);        [..]
                                            ib_unregister_device()
                                            /* Valid reference to
                                             * device->dev exists.
                                             */
                                             ib_dealloc_device()

          [..]
          provider->fill_res_entry();

Even though device object is not freed, fill_res_entry() can get called on
device which doesn't have a driver anymore. Kernel core device reference
count is not sufficient, as this only keeps the structure valid, and
doesn't guarantee the driver is still loaded.

Similar race can occur with device renaming and device removal, where
device_rename() tries to rename a unregistered device. While this is fine
for devices of a class which are not net namespace aware, but it is
incorrect for net namespace aware class coming in subsequent series.  If a
class is net namespace aware, then the below [1] call trace is observed in
above situation.

Therefore, to avoid the race, keep a reference count and let device
unregistration wait until all netlink users drop the reference.

[1] Call trace:
kernfs: ns required in 'infiniband' for 'mlx5_0'
WARNING: CPU: 18 PID: 44270 at fs/kernfs/dir.c:842 kernfs_find_ns+0x104/0x120
libahci i2c_core mlxfw libata dca [last unloaded: devlink]
RIP: 0010:kernfs_find_ns+0x104/0x120
Call Trace:
kernfs_find_and_get_ns+0x2e/0x50
sysfs_rename_link_ns+0x40/0xb0
device_rename+0xb2/0xf0
ib_device_rename+0xb3/0x100 [ib_core]
nldev_set_doit+0x165/0x190 [ib_core]
rdma_nl_rcv_msg+0x249/0x250 [ib_core]
? netlink_deliver_tap+0x8f/0x3e0
rdma_nl_rcv+0xd6/0x120 [ib_core]
netlink_unicast+0x17c/0x230
netlink_sendmsg+0x2f0/0x3e0
sock_sendmsg+0x30/0x40
__sys_sendto+0xdc/0x160

Fixes: da5c8507 ("RDMA/nldev: add driver-specific resource tracking")
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The 'tree' data structure is very hard to build at compile time, and this
makes it very limited. The new radix tree based compiler can handle a more
complex input language that does not require the compiler to perfectly
group everything into a neat tree structure.

Instead use a simple list to describe to input, where the list elements
can be of various different 'opcodes' instructing the radix compiler what
to do. Start out with opcodes chaining to other definition lists and
chaining to the existing 'tree' definition.

Replace the very top level of the 'object tree' with this list type and
get rid of struct uverbs_object_tree_def and DECLARE_UVERBS_OBJECT_TREE.
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>

Structures of ib_verbs.h don't use fields/structures of mm.h, socket.h or
scatterlist.h.  So remove such header files inclusion.
Signed-off-by: NParav Pandit <parav@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>