RDMA/core: Add an rb_tree that stores cm_ids sorted by ifindex and remote IP

Add to the cma, a tree that keeps track of all rdma_id_private channels
that were created while in RoCE mode.

The IDs are sorted first according to their netdevice ifindex then their
destination IP. And for IDs with matching IP they would be at the same node
in the tree, since the tree data is a list of all ids with matching destination IP.

The tree allows fast and efficient lookup of ids using an ifindex and
IP address which is useful for identifying relevant net_events promptly.

Link: https://lore.kernel.org/r/2fac52c86cc918c634ab24b3867d4aed992f54ec.1654601342.git.leonro@nvidia.com
Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Zhang <markzhang@nvidia.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

RDMA/cma: Split apart the multiple uses of the same list heads

Two list heads in the rdma_id_private are being used for multiple
purposes, to save a few bytes of memory. Give the different purposes
different names and union the memory that is clearly exclusive.

list splits into device_item and listen_any_item. device_item is threaded
onto the cma_device's list and listen_any goes onto the
listen_any_list. IDs doing any listen cannot have devices.

listen_list splits into listen_item and listen_list. listen_list is on the
parent listen any rdma_id_private and listen_item is on child listen that
is bound to a specific cma_dev.

Which name should be used in which case depends on the state and other
factors of the rdma_id_private. Remap all the confusing references to make
sense with the new names, so at least there is some hope of matching the
necessary preconditions with each access.

Link: https://lore.kernel.org/r/0-v1-a5ead4a0c19d+c3a-cma_list_head_jgg@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/cma: Ensure rdma_addr_cancel() happens before issuing more requests

The FSM can run in a circle allowing rdma_resolve_ip() to be called twice
on the same id_priv. While this cannot happen without going through the
work, it violates the invariant that the same address resolution
background request cannot be active twice.

CPU 1 CPU 2

rdma_resolve_addr():
RDMA_CM_IDLE -> RDMA_CM_ADDR_QUERY
rdma_resolve_ip(addr_handler) #1

process_one_req(): for #1
addr_handler():
RDMA_CM_ADDR_QUERY -> RDMA_CM_ADDR_BOUND
mutex_unlock(&id_priv->handler_mutex);
[.. handler still running ..]

rdma_resolve_addr():
RDMA_CM_ADDR_BOUND -> RDMA_CM_ADDR_QUERY
rdma_resolve_ip(addr_handler)
!! two requests are now on the req_list

rdma_destroy_id():
destroy_id_handler_unlock():
_destroy_id():
cma_cancel_operation():
rdma_addr_cancel()

// process_one_req() self removes it
spin_lock_bh(&lock);
cancel_delayed_work(&req->work);
if (!list_empty(&req->list)) == true

! rdma_addr_cancel() returns after process_on_req #1 is done

kfree(id_priv)

process_one_req(): for #2
addr_handler():
mutex_lock(&id_priv->handler_mutex);
!! Use after free on id_priv

rdma_addr_cancel() expects there to be one req on the list and only
cancels the first one. The self-removal behavior of the work only happens
after the handler has returned. This yields a situations where the
req_list can have two reqs for the same "handle" but rdma_addr_cancel()
only cancels the first one.

The second req remains active beyond rdma_destroy_id() and will
use-after-free id_priv once it inevitably triggers.

Fix this by remembering if the id_priv has called rdma_resolve_ip() and
always cancel before calling it again. This ensures the req_list never
gets more than one item in it and doesn't cost anything in the normal flow
that never uses this strange error path.

Link: https://lore.kernel.org/r/0-v1-3bc675b8006d+22-syz_cancel_uaf_jgg@nvidia.com
Cc: stable@vger.kernel.org
Fixes: e51060f08a61 ("IB: IP address based RDMA connection manager")
Reported-by: syzbot+dc3dfba010d7671e05f5@syzkaller.appspotmail.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/cma: Introduce rdma_set_min_rnr_timer()

Introduce the ability for kernel ULPs to adjust the minimum RNR Retry
timer. The INIT -> RTR transition executed by RDMA CM will be used for
this adjustment. This avoids an additional ib_modify_qp() call.

rdma_set_min_rnr_timer() must be called before the call to rdma_connect()
on the active side and before the call to rdma_accept() on the passive
side.

The default value of RNR Retry timer is zero, which translates to 655
ms. When the receiver is not ready to accept a send messages, it encodes
the RNR Retry timer value in the NAK. The requestor will then wait at
least the specified time value before retrying the send.

The 5-bit value to be supplied to the rdma_set_min_rnr_timer() is
documented in IBTA Table 45: "Encoding for RNR NAK Timer Field".

Link: https://lore.kernel.org/r/1617216194-12890-2-git-send-email-haakon.bugge@oracle.com
Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Support more than 255 rdma ports

Current code uses many different types when dealing with a port of a RDMA
device: u8, unsigned int and u32. Switch to u32 to clean up the logic.

This allows us to make (at least) the core view consistent and use the
same type. Unfortunately not all places can be converted. Many uverbs
functions expect port to be u8 so keep those places in order not to break
UAPIs. HW/Spec defined values must also not be changed.

With the switch to u32 we now can support devices with more than 255
ports. U32_MAX is reserved to make control logic a bit easier to deal
with. As a device with U32_MAX ports probably isn't going to happen any
time soon this seems like a non issue.

When a device with more than 255 ports is created uverbs will report the
RDMA device as having 255 ports as this is the max currently supported.

The verbs interface is not changed yet because the IBTA spec limits the
port size in too many places to be u8 and all applications that relies in
verbs won't be able to cope with this change. At this stage, we are
extending the interfaces that are using vendor channel solely

Once the limitation is lifted mlx5 in switchdev mode will be able to have
thousands of SFs created by the device. As the only instance of an RDMA
device that reports more than 255 ports will be a representor device and
it exposes itself as a RAW Ethernet only device CM/MAD/IPoIB and other
ULPs aren't effected by this change and their sysfs/interfaces that are
exposes to userspace can remain unchanged.

While here cleanup some alignment issues and remove unneeded sanity
checks (mainly in rdmavt),

Link: https://lore.kernel.org/r/20210301070420.439400-1-leon@kernel.org
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/ucma: Extend ucma_connect to receive ECE parameters

Active side of CMID initiates connection through librdmacm's
rdma_connect() and kernel's ucma_connect(). Extend UCMA interface to
handle those new parameters.

Link: https://lore.kernel.org/r/20200526103304.196371-3-leon@kernel.org
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/cma: Use refcount API to reflect refcount

Use a refcount_t for atomics being used as a refcount.

Link: https://lore.kernel.org/r/20200126142652.104803-8-leon@kernel.org
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/cma: Rename cma_device ref/deref helpers to to get/put

Helper functions which increment/decrement reference count of the
structure read better when they are named with the get/put suffix.

Hence, rename cma_ref/deref_dev() to cma_dev_get/put().

Link: https://lore.kernel.org/r/20200126142652.104803-5-leon@kernel.org
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/cma: Define option to set ack timeout and pack tos_set

Define new option in 'rdma_set_option' to override calculated QP timeout
when requested to provide QP attributes to modify a QP.

At the same time, pack tos_set to be bitfield.

Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/cma: Move cma module specific functions to cma_priv.h

Currently several rdma_cm module specific functions are declared in
core_priv.h file. Now that we have cma_priv.h file specific to rdma_cm
kernel module, move them from core_priv.h to cma_priv.h

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

RDMA/cma: Move rdma_cm_state to cma_priv.h

rdma_cm_state enum is internal to rdma_cm kernel module.
It is not required to expose state enums to ULP modules.
So lets keep its scope limited to rdma_cm module in cma_priv.h file.

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

RDMA/nldev: provide detailed CM_ID information

Implement RDMA nldev netlink interface to get detailed CM_ID information.

Because cm_id's are attached to rdma devices in various work queue
contexts, the pid and task information at restrak_add() time is sometimes
not useful. For example, an nvme/f host connection cm_id ends up being
bound to a device in a work queue context and the resulting pid at attach
time no longer exists after connection setup. So instead we mark all
cm_id's created via the rdma_ucm as "user", and all others as "kernel".
This required tweaking the restrack code a little. It also required
wrapping some rdma_cm functions to allow passing the module name string.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

RDMA/CM: move rdma_id_private to cma_priv.h

Move struct rdma_id_private to a new header cma_priv.h so the resource
tracking services in core/nldev.c can read useful information about cm_ids.

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>