cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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opfn.h (2835B)

      1/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
      2/*
      3 * Copyright(c) 2018 Intel Corporation.
      4 *
      5 */
      6#ifndef _HFI1_OPFN_H
      7#define _HFI1_OPFN_H
      8
      9/**
     10 * DOC: Omni Path Feature Negotion (OPFN)
     11 *
     12 * OPFN is a discovery protocol for Intel Omni-Path fabric that
     13 * allows two RC QPs to negotiate a common feature that both QPs
     14 * can support. Currently, the only OPA feature that OPFN
     15 * supports is TID RDMA.
     16 *
     17 * Architecture
     18 *
     19 * OPFN involves the communication between two QPs on the HFI
     20 * level on an Omni-Path fabric, and ULPs have no knowledge of
     21 * OPFN at all.
     22 *
     23 * Implementation
     24 *
     25 * OPFN extends the existing IB RC protocol with the following
     26 * changes:
     27 * -- Uses Bit 24 (reserved) of DWORD 1 of Base Transport
     28 *    Header (BTH1) to indicate that the RC QP supports OPFN;
     29 * -- Uses a combination of RC COMPARE_SWAP opcode (0x13) and
     30 *    the address U64_MAX (0xFFFFFFFFFFFFFFFF) as an OPFN
     31 *    request; The 64-bit data carried with the request/response
     32 *    contains the parameters for negotiation and will be
     33 *    defined in tid_rdma.c file;
     34 * -- Defines IB_WR_RESERVED3 as IB_WR_OPFN.
     35 *
     36 * The OPFN communication will be triggered when an RC QP
     37 * receives a request with Bit 24 of BTH1 set. The responder QP
     38 * will then post send an OPFN request with its local
     39 * parameters, which will be sent to the requester QP once all
     40 * existing requests on the responder QP side have been sent.
     41 * Once the requester QP receives the OPFN request, it will
     42 * keep a copy of the responder QP's parameters, and return a
     43 * response packet with its own local parameters. The responder
     44 * QP receives the response packet and keeps a copy of the requester
     45 * QP's parameters. After this exchange, each side has the parameters
     46 * for both sides and therefore can select the right parameters
     47 * for future transactions
     48 */
     49
     50#include <linux/workqueue.h>
     51#include <rdma/ib_verbs.h>
     52#include <rdma/rdmavt_qp.h>
     53
     54/* STL Verbs Extended */
     55#define IB_BTHE_E_SHIFT           24
     56#define HFI1_VERBS_E_ATOMIC_VADDR U64_MAX
     57
     58enum hfi1_opfn_codes {
     59	STL_VERBS_EXTD_NONE = 0,
     60	STL_VERBS_EXTD_TID_RDMA,
     61	STL_VERBS_EXTD_MAX
     62};
     63
     64struct hfi1_opfn_data {
     65	u8 extended;
     66	u16 requested;
     67	u16 completed;
     68	enum hfi1_opfn_codes curr;
     69	/* serialize opfn function calls */
     70	spinlock_t lock;
     71	struct work_struct opfn_work;
     72};
     73
     74/* WR opcode for OPFN */
     75#define IB_WR_OPFN IB_WR_RESERVED3
     76
     77void opfn_send_conn_request(struct work_struct *work);
     78void opfn_conn_response(struct rvt_qp *qp, struct rvt_ack_entry *e,
     79			struct ib_atomic_eth *ateth);
     80void opfn_conn_reply(struct rvt_qp *qp, u64 data);
     81void opfn_conn_error(struct rvt_qp *qp);
     82void opfn_qp_init(struct rvt_qp *qp, struct ib_qp_attr *attr, int attr_mask);
     83void opfn_trigger_conn_request(struct rvt_qp *qp, u32 bth1);
     84int opfn_init(void);
     85void opfn_exit(void);
     86
     87#endif /* _HFI1_OPFN_H */