kernel/linux.git/drivers/infiniband/core/multicast.c, branch linux-7.0.y

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This is the exact same thing as the 'alloc_obj()' version, only much smaller because there are a lot fewer users of the *alloc_flex() interface. As with alloc_obj() version, this was done entirely with mindless brute force, using the same script, except using 'flex' in the pattern rather than 'objs*'. Signed-off-by: Linus Torvalds

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

RDMA/core: Use refcount_t instead of atomic_t on refcount of mcast_port

2021-06-08T17:45:07+00:00

The refcount_t API will WARN on underflow and overflow of a reference counter, and avoid use-after-free risks. Link: https://lore.kernel.org/r/1622194663-2383-6-git-send-email-liweihang@huawei.com Signed-off-by: Weihang Li Signed-off-by: Jason Gunthorpe

RDMA/core: Use refcount_t instead of atomic_t on refcount of mcast_member

2021-06-08T17:43:56+00:00

The refcount_t API will WARN on underflow and overflow of a reference counter, and avoid use-after-free risks. Link: https://lore.kernel.org/r/1622194663-2383-5-git-send-email-liweihang@huawei.com Signed-off-by: Weihang Li Signed-off-by: Jason Gunthorpe

RDMA: Support more than 255 rdma ports

2021-03-26T12:31:21+00:00

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 Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe

RDMA/core/multicast: Provide description for 'ib_init_ah_from_mcmember()'s 'rec' param

2021-01-20T00:33:42+00:00

Fixes the following W=1 kernel build warning(s): drivers/infiniband/core/multicast.c:739: warning: Function parameter or member 'rec' not described in 'ib_init_ah_from_mcmember' Link: https://lore.kernel.org/r/20210118223929.512175-12-lee.jones@linaro.org Cc: Doug Ledford Cc: Jason Gunthorpe Cc: linux-rdma@vger.kernel.org Signed-off-by: Lee Jones Signed-off-by: Jason Gunthorpe

RDMA: Allow ib_client's to fail when add() is called

2020-05-06T14:57:33+00:00

When a client is added it isn't allowed to fail, but all the client's have various failure paths within their add routines. This creates the very fringe condition where the client was added, failed during add and didn't set the client_data. The core code will then still call other client_data centric ops like remove(), rename(), get_nl_info(), and get_net_dev_by_params() with NULL client_data - which is confusing and unexpected. If the add() callback fails, then do not call any more client ops for the device, even remove. Remove all the now redundant checks for NULL client_data in ops callbacks. Update all the add() callbacks to return error codes appropriately. EOPNOTSUPP is used for cases where the ULP does not support the ib_device - eg because it only works with IB. Link: https://lore.kernel.org/r/20200421172440.387069-1-leon@kernel.org Signed-off-by: Leon Romanovsky Acked-by: Ursula Braun Signed-off-by: Jason Gunthorpe

RDMA: Replace zero-length array with flexible-array member

2020-02-20T17:33:51+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Link: https://lore.kernel.org/r/20200213010425.GA13068@embeddedor.com Signed-off-by: Gustavo A. R. Silva Signed-off-by: Jason Gunthorpe # added a few more

IB/core, ipoib: Do not overreact to SM LID change event

2019-05-07T19:06:03+00:00

When IPoIB receives an SM LID change event, it reacts by flushing its path record cache and rejoining multicast groups. This is the same behavior it performs when it receives a reregistration event. This behavior is unnecessary as an SM may have database backup or synchronization mechanisms which permit the SM location or LID to change without loss of multicast membership and without impact to path records. Both opensm and the OPA FM issue reregistration events if a new SM is started (or restarted with a new config) or an SM event occurs which results in loss of multicast membership records by the SM (such as opensm failover) or the SM encounters new nodes with Active ports (such as after joining 2 fabrics by connecting switches via ISLs). Hence this event can be depended on as the trigger for IPoIB cache and multicast flushing. It appears that some drivers, such as qib, and hfi1 issue the IB_EVENT_SM_CHANGE but other drivers such as mlx4 and mlx5 do not. Empirical testing on Mellanox EDR using ibv_asyncwatch has confirmed that Mellanox EDR HCAs do not generate SM change events and that opensm does generate reregistration. An SM LID change event is generated by the mentioned drivers to reflect that sm_lid and/or sm_sl in the local port info has changed. The intent of this event is to permit applications and ULPs which have a local copy of this information (or an address handle using it) to update their information. The intent is that the reregistration event (caused by the SM via a bit in Set(PortInfo)) be used to inform nodes that they need to rejoin multicast groups, resubscribe for notices and potentially update path records. When an SM migrates or fails over, a SM LID change event can occur. In response IPoIB discards path records and multicast membership and loses connectivity until these records are restored via SA requests. In very large fabrics, it may take minutes for the SM to be ready and for the SA responses to be supplied. This can result in undesirable and unnecessary IPoIB connectivity impacts. It also can result in an unnecessary storm of SA queries from all nodes in a cluster potentially followed by yet another storm if the SM issues the reregistration request. The fact the Mellanox HCAs do not even generate this event, is further evidence that on modern IB fabrics there will be no ill side effects from the proposed changes below to reduce the reaction by 3 kernel components to this event. So these changes should be benign for Mellanox IB fabrics and will benefit OPA fabrics while also making ib_core and ULP behavor "correct" as intended by the IBTA spec and kernel RDMA event APIs. Address these issues by removing IB_EVENT_SM_CHANGE handling from ipoib. IPoIB does not locally store sm_lid nor sm_sl, so it does not need to do anything on SM LID change. IPoIB makes use of other ib_core components to issue SA requests for it and those components correctly track SM LID and SM LID changes. Also in ib_core multicast handling, remove the test for IB_EVENT_SM_CHANGE. This code is moving all multicast groups to the error state, which will trigger rejoins. This code is used by IPoIB as well as the connection manager and other clients of multicast groups. This kernel module centralizes group membership status and joins since a node can only join a given group once but multiple ULPs or applications may want to join the same group. It makes use of the sa_query.c component in ib_core, which correctly trackes SM LID and SL. This component does not track SM LID nor SL itself and hence need not react to their changes. Similarly in the ib_core cache code remove the handling for the IB_EVENT_SM_CHANGE. In this function. The ib_cache_update function which is ultimately called is updating local copies of the pkey table, gid table and lmc. It does not update nor retain sm_lid nor sm_sl. As such it does not need to be called on an SM LID change. It technically also does not need to be called on a reregistration. The LID_CHANGE, PKEY_CHANGE, GID_CHANGE and port state change events (PORT_ERR, PORT_ACTICE) should be sufficient triggers. It is worth noting that the alternative of simply having the hfi1 and qib drivers not generate the SM LID change event was explored. While this would duplicate what Mellanox drivers do now, it is not the correct behavior and removes the ability for an SM to migrate without requiring reregistration. Since both opensm and OPA SM have mechanisms to backup or synchronize registration information, it is desirable to let them perform SM migrations (with LID or SL changes) without requiring reregistration when they deem it appropriate. Suggested-by: Todd Rimmer Tested-by: Michael Brooks Reviewed-by: Mike Marciniszyn Reviewed-by: Todd Rimmer Signed-off-by: Dennis Dalessandro Signed-off-by: Jason Gunthorpe

IB: Make ib_init_ah_from_mcmember set sgid_attr

2018-06-25T20:19:56+00:00

This is really just a CM support function, normally a multicast address does not have a specific SGID - but the RDMA CM usage model does restrict things to the netdevice the CM id is bound to, at least for roce case. Store the selected table entry in the sgid_attr for everything else to use. Signed-off-by: Parav Pandit Signed-off-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky