linux/include/rdma/rdma_cm.h
Jason Gunthorpe 071ba4cc55 RDMA: Add rdma_connect_locked()
There are two flows for handling RDMA_CM_EVENT_ROUTE_RESOLVED, either the
handler triggers a completion and another thread does rdma_connect() or
the handler directly calls rdma_connect().

In all cases rdma_connect() needs to hold the handler_mutex, but when
handler's are invoked this is already held by the core code. This causes
ULPs using the 2nd method to deadlock.

Provide a rdma_connect_locked() and have all ULPs call it from their
handlers.

Link: https://lore.kernel.org/r/0-v2-53c22d5c1405+33-rdma_connect_locking_jgg@nvidia.com
Reported-and-tested-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Fixes: 2a7cec5381 ("RDMA/cma: Fix locking for the RDMA_CM_CONNECT state")
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-28 09:14:49 -03:00

381 lines
13 KiB
C

/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
/*
* Copyright (c) 2005 Voltaire Inc. All rights reserved.
* Copyright (c) 2005 Intel Corporation. All rights reserved.
*/
#ifndef RDMA_CM_H
#define RDMA_CM_H
#include <linux/socket.h>
#include <linux/in6.h>
#include <rdma/ib_addr.h>
#include <rdma/ib_sa.h>
#include <uapi/rdma/rdma_user_cm.h>
/*
* Upon receiving a device removal event, users must destroy the associated
* RDMA identifier and release all resources allocated with the device.
*/
enum rdma_cm_event_type {
RDMA_CM_EVENT_ADDR_RESOLVED,
RDMA_CM_EVENT_ADDR_ERROR,
RDMA_CM_EVENT_ROUTE_RESOLVED,
RDMA_CM_EVENT_ROUTE_ERROR,
RDMA_CM_EVENT_CONNECT_REQUEST,
RDMA_CM_EVENT_CONNECT_RESPONSE,
RDMA_CM_EVENT_CONNECT_ERROR,
RDMA_CM_EVENT_UNREACHABLE,
RDMA_CM_EVENT_REJECTED,
RDMA_CM_EVENT_ESTABLISHED,
RDMA_CM_EVENT_DISCONNECTED,
RDMA_CM_EVENT_DEVICE_REMOVAL,
RDMA_CM_EVENT_MULTICAST_JOIN,
RDMA_CM_EVENT_MULTICAST_ERROR,
RDMA_CM_EVENT_ADDR_CHANGE,
RDMA_CM_EVENT_TIMEWAIT_EXIT
};
const char *__attribute_const__ rdma_event_msg(enum rdma_cm_event_type event);
#define RDMA_IB_IP_PS_MASK 0xFFFFFFFFFFFF0000ULL
#define RDMA_IB_IP_PS_TCP 0x0000000001060000ULL
#define RDMA_IB_IP_PS_UDP 0x0000000001110000ULL
#define RDMA_IB_IP_PS_IB 0x00000000013F0000ULL
struct rdma_addr {
struct sockaddr_storage src_addr;
struct sockaddr_storage dst_addr;
struct rdma_dev_addr dev_addr;
};
struct rdma_route {
struct rdma_addr addr;
struct sa_path_rec *path_rec;
int num_paths;
};
struct rdma_conn_param {
const void *private_data;
u8 private_data_len;
u8 responder_resources;
u8 initiator_depth;
u8 flow_control;
u8 retry_count; /* ignored when accepting */
u8 rnr_retry_count;
/* Fields below ignored if a QP is created on the rdma_cm_id. */
u8 srq;
u32 qp_num;
u32 qkey;
};
struct rdma_ud_param {
const void *private_data;
u8 private_data_len;
struct rdma_ah_attr ah_attr;
u32 qp_num;
u32 qkey;
};
struct rdma_cm_event {
enum rdma_cm_event_type event;
int status;
union {
struct rdma_conn_param conn;
struct rdma_ud_param ud;
} param;
struct rdma_ucm_ece ece;
};
struct rdma_cm_id;
/**
* rdma_cm_event_handler - Callback used to report user events.
*
* Notes: Users may not call rdma_destroy_id from this callback to destroy
* the passed in id, or a corresponding listen id. Returning a
* non-zero value from the callback will destroy the passed in id.
*/
typedef int (*rdma_cm_event_handler)(struct rdma_cm_id *id,
struct rdma_cm_event *event);
struct rdma_cm_id {
struct ib_device *device;
void *context;
struct ib_qp *qp;
rdma_cm_event_handler event_handler;
struct rdma_route route;
enum rdma_ucm_port_space ps;
enum ib_qp_type qp_type;
u8 port_num;
};
struct rdma_cm_id *
__rdma_create_kernel_id(struct net *net, rdma_cm_event_handler event_handler,
void *context, enum rdma_ucm_port_space ps,
enum ib_qp_type qp_type, const char *caller);
struct rdma_cm_id *rdma_create_user_id(rdma_cm_event_handler event_handler,
void *context,
enum rdma_ucm_port_space ps,
enum ib_qp_type qp_type);
/**
* rdma_create_id - Create an RDMA identifier.
*
* @net: The network namespace in which to create the new id.
* @event_handler: User callback invoked to report events associated with the
* returned rdma_id.
* @context: User specified context associated with the id.
* @ps: RDMA port space.
* @qp_type: type of queue pair associated with the id.
*
* Returns a new rdma_cm_id. The id holds a reference on the network
* namespace until it is destroyed.
*
* The event handler callback serializes on the id's mutex and is
* allowed to sleep.
*/
#define rdma_create_id(net, event_handler, context, ps, qp_type) \
__rdma_create_kernel_id(net, event_handler, context, ps, qp_type, \
KBUILD_MODNAME)
/**
* rdma_destroy_id - Destroys an RDMA identifier.
*
* @id: RDMA identifier.
*
* Note: calling this function has the effect of canceling in-flight
* asynchronous operations associated with the id.
*/
void rdma_destroy_id(struct rdma_cm_id *id);
/**
* rdma_bind_addr - Bind an RDMA identifier to a source address and
* associated RDMA device, if needed.
*
* @id: RDMA identifier.
* @addr: Local address information. Wildcard values are permitted.
*
* This associates a source address with the RDMA identifier before calling
* rdma_listen. If a specific local address is given, the RDMA identifier will
* be bound to a local RDMA device.
*/
int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr);
/**
* rdma_resolve_addr - Resolve destination and optional source addresses
* from IP addresses to an RDMA address. If successful, the specified
* rdma_cm_id will be bound to a local device.
*
* @id: RDMA identifier.
* @src_addr: Source address information. This parameter may be NULL.
* @dst_addr: Destination address information.
* @timeout_ms: Time to wait for resolution to complete.
*/
int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
const struct sockaddr *dst_addr,
unsigned long timeout_ms);
/**
* rdma_resolve_route - Resolve the RDMA address bound to the RDMA identifier
* into route information needed to establish a connection.
*
* This is called on the client side of a connection.
* Users must have first called rdma_resolve_addr to resolve a dst_addr
* into an RDMA address before calling this routine.
*/
int rdma_resolve_route(struct rdma_cm_id *id, unsigned long timeout_ms);
/**
* rdma_create_qp - Allocate a QP and associate it with the specified RDMA
* identifier.
*
* QPs allocated to an rdma_cm_id will automatically be transitioned by the CMA
* through their states.
*/
int rdma_create_qp(struct rdma_cm_id *id, struct ib_pd *pd,
struct ib_qp_init_attr *qp_init_attr);
/**
* rdma_destroy_qp - Deallocate the QP associated with the specified RDMA
* identifier.
*
* Users must destroy any QP associated with an RDMA identifier before
* destroying the RDMA ID.
*/
void rdma_destroy_qp(struct rdma_cm_id *id);
/**
* rdma_init_qp_attr - Initializes the QP attributes for use in transitioning
* to a specified QP state.
* @id: Communication identifier associated with the QP attributes to
* initialize.
* @qp_attr: On input, specifies the desired QP state. On output, the
* mandatory and desired optional attributes will be set in order to
* modify the QP to the specified state.
* @qp_attr_mask: The QP attribute mask that may be used to transition the
* QP to the specified state.
*
* Users must set the @qp_attr->qp_state to the desired QP state. This call
* will set all required attributes for the given transition, along with
* known optional attributes. Users may override the attributes returned from
* this call before calling ib_modify_qp.
*
* Users that wish to have their QP automatically transitioned through its
* states can associate a QP with the rdma_cm_id by calling rdma_create_qp().
*/
int rdma_init_qp_attr(struct rdma_cm_id *id, struct ib_qp_attr *qp_attr,
int *qp_attr_mask);
int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
int rdma_connect_locked(struct rdma_cm_id *id,
struct rdma_conn_param *conn_param);
int rdma_connect_ece(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
struct rdma_ucm_ece *ece);
/**
* rdma_listen - This function is called by the passive side to
* listen for incoming connection requests.
*
* Users must have bound the rdma_cm_id to a local address by calling
* rdma_bind_addr before calling this routine.
*/
int rdma_listen(struct rdma_cm_id *id, int backlog);
int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param);
void rdma_lock_handler(struct rdma_cm_id *id);
void rdma_unlock_handler(struct rdma_cm_id *id);
int rdma_accept_ece(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
struct rdma_ucm_ece *ece);
/**
* rdma_notify - Notifies the RDMA CM of an asynchronous event that has
* occurred on the connection.
* @id: Connection identifier to transition to established.
* @event: Asynchronous event.
*
* This routine should be invoked by users to notify the CM of relevant
* communication events. Events that should be reported to the CM and
* when to report them are:
*
* IB_EVENT_COMM_EST - Used when a message is received on a connected
* QP before an RTU has been received.
*/
int rdma_notify(struct rdma_cm_id *id, enum ib_event_type event);
/**
* rdma_reject - Called to reject a connection request or response.
*/
int rdma_reject(struct rdma_cm_id *id, const void *private_data,
u8 private_data_len, u8 reason);
/**
* rdma_disconnect - This function disconnects the associated QP and
* transitions it into the error state.
*/
int rdma_disconnect(struct rdma_cm_id *id);
/**
* rdma_join_multicast - Join the multicast group specified by the given
* address.
* @id: Communication identifier associated with the request.
* @addr: Multicast address identifying the group to join.
* @join_state: Multicast JoinState bitmap requested by port.
* Bitmap is based on IB_SA_MCMEMBER_REC_JOIN_STATE bits.
* @context: User-defined context associated with the join request, returned
* to the user through the private_data pointer in multicast events.
*/
int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
u8 join_state, void *context);
/**
* rdma_leave_multicast - Leave the multicast group specified by the given
* address.
*/
void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
/**
* rdma_set_service_type - Set the type of service associated with a
* connection identifier.
* @id: Communication identifier to associated with service type.
* @tos: Type of service.
*
* The type of service is interpretted as a differentiated service
* field (RFC 2474). The service type should be specified before
* performing route resolution, as existing communication on the
* connection identifier may be unaffected. The type of service
* requested may not be supported by the network to all destinations.
*/
void rdma_set_service_type(struct rdma_cm_id *id, int tos);
/**
* rdma_set_reuseaddr - Allow the reuse of local addresses when binding
* the rdma_cm_id.
* @id: Communication identifier to configure.
* @reuse: Value indicating if the bound address is reusable.
*
* Reuse must be set before an address is bound to the id.
*/
int rdma_set_reuseaddr(struct rdma_cm_id *id, int reuse);
/**
* rdma_set_afonly - Specify that listens are restricted to the
* bound address family only.
* @id: Communication identifer to configure.
* @afonly: Value indicating if listens are restricted.
*
* Must be set before identifier is in the listening state.
*/
int rdma_set_afonly(struct rdma_cm_id *id, int afonly);
int rdma_set_ack_timeout(struct rdma_cm_id *id, u8 timeout);
/**
* rdma_get_service_id - Return the IB service ID for a specified address.
* @id: Communication identifier associated with the address.
* @addr: Address for the service ID.
*/
__be64 rdma_get_service_id(struct rdma_cm_id *id, struct sockaddr *addr);
/**
* rdma_reject_msg - return a pointer to a reject message string.
* @id: Communication identifier that received the REJECT event.
* @reason: Value returned in the REJECT event status field.
*/
const char *__attribute_const__ rdma_reject_msg(struct rdma_cm_id *id,
int reason);
/**
* rdma_consumer_reject_data - return the consumer reject private data and
* length, if any.
* @id: Communication identifier that received the REJECT event.
* @ev: RDMA CM reject event.
* @data_len: Pointer to the resulting length of the consumer data.
*/
const void *rdma_consumer_reject_data(struct rdma_cm_id *id,
struct rdma_cm_event *ev, u8 *data_len);
/**
* rdma_read_gids - Return the SGID and DGID used for establishing
* connection. This can be used after rdma_resolve_addr()
* on client side. This can be use on new connection
* on server side. This is applicable to IB, RoCE, iWarp.
* If cm_id is not bound yet to the RDMA device, it doesn't
* copy and SGID or DGID to the given pointers.
* @id: Communication identifier whose GIDs are queried.
* @sgid: Pointer to SGID where SGID will be returned. It is optional.
* @dgid: Pointer to DGID where DGID will be returned. It is optional.
* Note: This API should not be used by any new ULPs or new code.
* Instead, users interested in querying GIDs should refer to path record
* of the rdma_cm_id to query the GIDs.
* This API is provided for compatibility for existing users.
*/
void rdma_read_gids(struct rdma_cm_id *cm_id, union ib_gid *sgid,
union ib_gid *dgid);
struct iw_cm_id *rdma_iw_cm_id(struct rdma_cm_id *cm_id);
struct rdma_cm_id *rdma_res_to_id(struct rdma_restrack_entry *res);
#endif /* RDMA_CM_H */