1IBV_MODIFY_QP(3) Libibverbs Programmer's Manual IBV_MODIFY_QP(3)
2
6 ibv_modify_qp - modify the attributes of a queue pair (QP)
7
9 #include <infiniband/verbs.h>
10 int ibv_modify_qp(struct ibv_qp *qp, struct ibv_qp_attr *attr,
12 int attr_mask);
13
15 ibv_modify_qp() modifies the attributes of QP qp with the attributes in
16 attr according to the mask attr_mask. The argument attr is an
17 ibv_qp_attr struct, as defined in <infiniband/verbs.h>.
18 struct ibv_qp_attr {
20 enum ibv_qp_state qp_state; /* Move the QP to this state */
21 enum ibv_qp_state cur_qp_state; /* Assume this is the current QP state */
22 enum ibv_mtu path_mtu; /* Path MTU (valid only for RC/UC QPs) */
23 enum ibv_mig_state path_mig_state; /* Path migration state (valid if HCA supports APM) */
24 uint32_t qkey; /* Q_Key for the QP (valid only for UD QPs) */
25 uint32_t rq_psn; /* PSN for receive queue (valid only for RC/UC QPs) */
26 uint32_t sq_psn; /* PSN for send queue (valid only for RC/UC QPs) */
27 uint32_t dest_qp_num; /* Destination QP number (valid only for RC/UC QPs) */
28 int qp_access_flags; /* Mask of enabled remote access operations (valid only for RC/UC QPs) */
29 struct ibv_qp_cap cap; /* QP capabilities (valid if HCA supports QP resizing) */
30 struct ibv_ah_attr ah_attr; /* Primary path address vector (valid only for RC/UC QPs) */
31 struct ibv_ah_attr alt_ah_attr; /* Alternate path address vector (valid only for RC/UC QPs) */
32 uint16_t pkey_index; /* Primary P_Key index */
33 uint16_t alt_pkey_index; /* Alternate P_Key index */
34 uint8_t en_sqd_async_notify; /* Enable SQD.drained async notification (Valid only if qp_state is SQD) */
35 uint8_t sq_draining; /* Is the QP draining? Irrelevant for ibv_modify_qp() */
36 uint8_t max_rd_atomic; /* Number of outstanding RDMA reads & atomic operations on the destination QP (valid only for RC QPs) */
37 uint8_t max_dest_rd_atomic; /* Number of responder resources for handling incoming RDMA reads & atomic operations (valid only for RC QPs) */
38 uint8_t min_rnr_timer; /* Minimum RNR NAK timer (valid only for RC QPs) */
39 uint8_t port_num; /* Primary port number */
40 uint8_t timeout; /* Local ack timeout for primary path (valid only for RC QPs) */
41 uint8_t retry_cnt; /* Retry count (valid only for RC QPs) */
42 uint8_t rnr_retry; /* RNR retry (valid only for RC QPs) */
43 uint8_t alt_port_num; /* Alternate port number */
44 uint8_t alt_timeout; /* Local ack timeout for alternate path (valid only for RC QPs) */
45 };
46 For details on struct ibv_qp_cap see the description of ibv_cre‐
48 ate_qp(). For details on struct ibv_ah_attr see the description of
49 ibv_create_ah().
50 The argument attr_mask specifies the QP attributes to be modified. The
52 argument is either 0 or the bitwise OR of one or more of the following
53 flags:
54 IBV_QP_STATE Modify qp_state
56 IBV_QP_CUR_STATE Set cur_qp_state
58 IBV_QP_EN_SQD_ASYNC_NOTIFY Set en_sqd_async_notify
60 IBV_QP_ACCESS_FLAGS Set qp_access_flags
62 IBV_QP_PKEY_INDEX Set pkey_index
64 IBV_QP_PORT Set port_num
66 IBV_QP_QKEY Set qkey
68 IBV_QP_AV Set ah_attr
70 IBV_QP_PATH_MTU Set path_mtu
72 IBV_QP_TIMEOUT Set timeout
74 IBV_QP_RETRY_CNT Set retry_cnt
76 IBV_QP_RNR_RETRY Set rnr_retry
78 IBV_QP_RQ_PSN Set rq_psn
80 IBV_QP_MAX_QP_RD_ATOMIC Set max_rd_atomic
82 IBV_QP_ALT_PATH Set the alternative path via: alt_ah_attr,
84 alt_pkey_index, alt_port_num, alt_timeout
85 IBV_QP_MIN_RNR_TIMER Set min_rnr_timer
87 IBV_QP_SQ_PSN Set sq_psn
89 IBV_QP_MAX_DEST_RD_ATOMIC Set max_dest_rd_atomic
91 IBV_QP_PATH_MIG_STATE Set path_mig_state
93 IBV_QP_CAP Set cap
95 IBV_QP_DEST_QPN Set dest_qp_num
97
99 ibv_modify_qp() returns 0 on success, or the value of errno on failure
100 (which indicates the failure reason).
101
103 If any of the modify attributes or the modify mask are invalid, none of
104 the attributes will be modified (including the QP state).
105 Not all devices support resizing QPs. To check if a device supports
107 it, check if the IBV_DEVICE_RESIZE_MAX_WR bit is set in the device
108 capabilities flags.
109 Not all devices support alternate paths. To check if a device supports
111 it, check if the IBV_DEVICE_AUTO_PATH_MIG bit is set in the device
112 capabilities flags.
113 The following tables indicate for each QP Transport Service Type, the
115 minimum list of attributes that must be changed upon transitioning QP
116 state from: Reset --> Init --> RTR --> RTS.
117 For QP Transport Service Type IBV_QPT_UD:
119 Next state Required attributes
121 ---------- ----------------------------------------
122 Init IBV_QP_STATE, IBV_QP_PKEY_INDEX, IBV_QP_PORT,
123 IBV_QP_QKEY
124 RTR IBV_QP_STATE
125 RTS IBV_QP_STATE, IBV_QP_SQ_PSN
126 For QP Transport Service Type IBV_QPT_UC:
128 Next state Required attributes
130 ---------- ----------------------------------------
131 Init IBV_QP_STATE, IBV_QP_PKEY_INDEX, IBV_QP_PORT,
132 IBV_QP_ACCESS_FLAGS
133 RTR IBV_QP_STATE, IBV_QP_AV, IBV_QP_PATH_MTU,
134 IBV_QP_DEST_QPN, IBV_QP_RQ_PSN
135 RTS IBV_QP_STATE, IBV_QP_SQ_PSN
136 For QP Transport Service Type IBV_QPT_RC:
138 Next state Required attributes
140 ---------- ----------------------------------------
141 Init IBV_QP_STATE, IBV_QP_PKEY_INDEX, IBV_QP_PORT,
142 IBV_QP_ACCESS_FLAGS
143 RTR IBV_QP_STATE, IBV_QP_AV, IBV_QP_PATH_MTU,
144 IBV_QP_DEST_QPN, IBV_QP_RQ_PSN,
145 IBV_QP_MAX_DEST_RD_ATOMIC, IBV_QP_MIN_RNR_TIMER
146 RTS IBV_QP_STATE, IBV_QP_SQ_PSN, IBV_QP_MAX_QP_RD_ATOMIC,
147 IBV_QP_RETRY_CNT, IBV_QP_RNR_RETRY, IBV_QP_TIMEOUT
148
150 ibv_create_qp(3), ibv_destroy_qp(3), ibv_query_qp(3), ibv_create_ah(3)
151
153 Dotan Barak <dotanba@gmail.com>
154libibverbs 2006-10-31 IBV_MODIFY_QP(3)