include/net/mctp.h

1 /* SPDX-License-Identifier: GPL-2.0 */
18 /* MCTP packet definitions */
79 	 * by sk->net->keys_lock
94  *  - individual key data (ie, the struct itself) is protected by key->lock;
97  *  - the lookup fields: peer_addr, local_addr and tag are set before the
100  *  - A ref to the key must be held (throuh key->refs) if a pointer to the
101  *    key is to be accessed after key->lock is released.
103  *  - a mctp_sk_key contains a reference to a struct sock; this is valid
107  * - these mctp_sk_keys appear on two lists:
108  *     1) the struct mctp_sock->keys list
109  *     2) the struct netns_mctp->keys list
115  *   netns_mctp->keys lock. Lookup functions will need to lock the key and
117  *   keys_lock *cannot* be acquired with the individual key->lock held.
119  * - a key may have a sk_buff attached as part of an in-progress message
120  *   reassembly (->reasm_head). The reasm data is protected by the individual
121  *   key->lock.
123  * - there are two destruction paths for a mctp_sk_key:
125  *    - through socket unhash (see mctp_sk_unhash). This performs the list
128  *    - where a key is established to receive a reply message: after receiving
133  *    - through an expiry timeout, on a per-socket timer
147 	/* per-socket list */
184 	unsigned int	magic;  member
192 /* skb control-block accessors with a little extra debugging for initial
195  * TODO: remove checks & mctp_skb_cb->magic; replace callers of __mctp_cb
198  * __mctp_cb() is only for the initial ingress code; we should see ->magic set
203 	struct mctp_skb_cb *cb = (void *)skb->cb;  in __mctp_cb()
205 	cb->magic = 0x4d435450;  in __mctp_cb()
211 	struct mctp_skb_cb *cb = (void *)skb->cb;  in mctp_cb()
213 	BUILD_BUG_ON(sizeof(struct mctp_skb_cb) > sizeof(skb->cb));  in mctp_cb()
214 	WARN_ON(cb->magic != 0x4d435450);  in mctp_cb()
215 	return (void *)(skb->cb);  in mctp_cb()
227  * These are held in the pernet->mctp.routes list, with RCU protection for
263 /* routing <--> device interface */