linux/net/sunrpc/xprtrdma/xprt_rdma.h
\"Talpey, Thomas\ f58851e6b0 RPCRDMA: rpc rdma transport switch
This implements the configuration and building of the core transport
switch implementation of the rpcrdma transport. Stubs are provided for
the rpcrdma protocol handling, and the infiniband/iwarp verbs interface.
These are provided in following patches.

Signed-off-by: Tom Talpey <talpey@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:03 -04:00

331 lines
12 KiB
C

/*
* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the BSD-type
* license below:
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* Neither the name of the Network Appliance, Inc. nor the names of
* its contributors may be used to endorse or promote products
* derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _LINUX_SUNRPC_XPRT_RDMA_H
#define _LINUX_SUNRPC_XPRT_RDMA_H
#include <linux/wait.h> /* wait_queue_head_t, etc */
#include <linux/spinlock.h> /* spinlock_t, etc */
#include <asm/atomic.h> /* atomic_t, etc */
#include <rdma/rdma_cm.h> /* RDMA connection api */
#include <rdma/ib_verbs.h> /* RDMA verbs api */
#include <linux/sunrpc/clnt.h> /* rpc_xprt */
#include <linux/sunrpc/rpc_rdma.h> /* RPC/RDMA protocol */
#include <linux/sunrpc/xprtrdma.h> /* xprt parameters */
/*
* Interface Adapter -- one per transport instance
*/
struct rpcrdma_ia {
struct rdma_cm_id *ri_id;
struct ib_pd *ri_pd;
struct ib_mr *ri_bind_mem;
struct completion ri_done;
int ri_async_rc;
enum rpcrdma_memreg ri_memreg_strategy;
};
/*
* RDMA Endpoint -- one per transport instance
*/
struct rpcrdma_ep {
atomic_t rep_cqcount;
int rep_cqinit;
int rep_connected;
struct rpcrdma_ia *rep_ia;
struct ib_cq *rep_cq;
struct ib_qp_init_attr rep_attr;
wait_queue_head_t rep_connect_wait;
struct ib_sge rep_pad; /* holds zeroed pad */
struct ib_mr *rep_pad_mr; /* holds zeroed pad */
void (*rep_func)(struct rpcrdma_ep *);
struct rpc_xprt *rep_xprt; /* for rep_func */
struct rdma_conn_param rep_remote_cma;
struct sockaddr_storage rep_remote_addr;
};
#define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
#define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)
/*
* struct rpcrdma_rep -- this structure encapsulates state required to recv
* and complete a reply, asychronously. It needs several pieces of
* state:
* o recv buffer (posted to provider)
* o ib_sge (also donated to provider)
* o status of reply (length, success or not)
* o bookkeeping state to get run by tasklet (list, etc)
*
* These are allocated during initialization, per-transport instance;
* however, the tasklet execution list itself is global, as it should
* always be pretty short.
*
* N of these are associated with a transport instance, and stored in
* struct rpcrdma_buffer. N is the max number of outstanding requests.
*/
/* temporary static scatter/gather max */
#define RPCRDMA_MAX_DATA_SEGS (8) /* max scatter/gather */
#define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */
#define MAX_RPCRDMAHDR (\
/* max supported RPC/RDMA header */ \
sizeof(struct rpcrdma_msg) + (2 * sizeof(u32)) + \
(sizeof(struct rpcrdma_read_chunk) * RPCRDMA_MAX_SEGS) + sizeof(u32))
struct rpcrdma_buffer;
struct rpcrdma_rep {
unsigned int rr_len; /* actual received reply length */
struct rpcrdma_buffer *rr_buffer; /* home base for this structure */
struct rpc_xprt *rr_xprt; /* needed for request/reply matching */
void (*rr_func)(struct rpcrdma_rep *);/* called by tasklet in softint */
struct list_head rr_list; /* tasklet list */
wait_queue_head_t rr_unbind; /* optional unbind wait */
struct ib_sge rr_iov; /* for posting */
struct ib_mr *rr_handle; /* handle for mem in rr_iov */
char rr_base[MAX_RPCRDMAHDR]; /* minimal inline receive buffer */
};
/*
* struct rpcrdma_req -- structure central to the request/reply sequence.
*
* N of these are associated with a transport instance, and stored in
* struct rpcrdma_buffer. N is the max number of outstanding requests.
*
* It includes pre-registered buffer memory for send AND recv.
* The recv buffer, however, is not owned by this structure, and
* is "donated" to the hardware when a recv is posted. When a
* reply is handled, the recv buffer used is given back to the
* struct rpcrdma_req associated with the request.
*
* In addition to the basic memory, this structure includes an array
* of iovs for send operations. The reason is that the iovs passed to
* ib_post_{send,recv} must not be modified until the work request
* completes.
*
* NOTES:
* o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we
* marshal. The number needed varies depending on the iov lists that
* are passed to us, the memory registration mode we are in, and if
* physical addressing is used, the layout.
*/
struct rpcrdma_mr_seg { /* chunk descriptors */
union { /* chunk memory handles */
struct ib_mr *rl_mr; /* if registered directly */
struct rpcrdma_mw { /* if registered from region */
union {
struct ib_mw *mw;
struct ib_fmr *fmr;
} r;
struct list_head mw_list;
} *rl_mw;
} mr_chunk;
u64 mr_base; /* registration result */
u32 mr_rkey; /* registration result */
u32 mr_len; /* length of chunk or segment */
int mr_nsegs; /* number of segments in chunk or 0 */
enum dma_data_direction mr_dir; /* segment mapping direction */
dma_addr_t mr_dma; /* segment mapping address */
size_t mr_dmalen; /* segment mapping length */
struct page *mr_page; /* owning page, if any */
char *mr_offset; /* kva if no page, else offset */
};
struct rpcrdma_req {
size_t rl_size; /* actual length of buffer */
unsigned int rl_niovs; /* 0, 2 or 4 */
unsigned int rl_nchunks; /* non-zero if chunks */
struct rpcrdma_buffer *rl_buffer; /* home base for this structure */
struct rpcrdma_rep *rl_reply;/* holder for reply buffer */
struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];/* chunk segments */
struct ib_sge rl_send_iov[4]; /* for active requests */
struct ib_sge rl_iov; /* for posting */
struct ib_mr *rl_handle; /* handle for mem in rl_iov */
char rl_base[MAX_RPCRDMAHDR]; /* start of actual buffer */
__u32 rl_xdr_buf[0]; /* start of returned rpc rq_buffer */
};
#define rpcr_to_rdmar(r) \
container_of((r)->rq_buffer, struct rpcrdma_req, rl_xdr_buf[0])
/*
* struct rpcrdma_buffer -- holds list/queue of pre-registered memory for
* inline requests/replies, and client/server credits.
*
* One of these is associated with a transport instance
*/
struct rpcrdma_buffer {
spinlock_t rb_lock; /* protects indexes */
atomic_t rb_credits; /* most recent server credits */
unsigned long rb_cwndscale; /* cached framework rpc_cwndscale */
int rb_max_requests;/* client max requests */
struct list_head rb_mws; /* optional memory windows/fmrs */
int rb_send_index;
struct rpcrdma_req **rb_send_bufs;
int rb_recv_index;
struct rpcrdma_rep **rb_recv_bufs;
char *rb_pool;
};
#define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia)
/*
* Internal structure for transport instance creation. This
* exists primarily for modularity.
*
* This data should be set with mount options
*/
struct rpcrdma_create_data_internal {
struct sockaddr_storage addr; /* RDMA server address */
unsigned int max_requests; /* max requests (slots) in flight */
unsigned int rsize; /* mount rsize - max read hdr+data */
unsigned int wsize; /* mount wsize - max write hdr+data */
unsigned int inline_rsize; /* max non-rdma read data payload */
unsigned int inline_wsize; /* max non-rdma write data payload */
unsigned int padding; /* non-rdma write header padding */
};
#define RPCRDMA_INLINE_READ_THRESHOLD(rq) \
(rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_rsize)
#define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\
(rpcx_to_rdmad(rq->rq_task->tk_xprt).inline_wsize)
#define RPCRDMA_INLINE_PAD_VALUE(rq)\
rpcx_to_rdmad(rq->rq_task->tk_xprt).padding
/*
* Statistics for RPCRDMA
*/
struct rpcrdma_stats {
unsigned long read_chunk_count;
unsigned long write_chunk_count;
unsigned long reply_chunk_count;
unsigned long long total_rdma_request;
unsigned long long total_rdma_reply;
unsigned long long pullup_copy_count;
unsigned long long fixup_copy_count;
unsigned long hardway_register_count;
unsigned long failed_marshal_count;
unsigned long bad_reply_count;
};
/*
* RPCRDMA transport -- encapsulates the structures above for
* integration with RPC.
*
* The contained structures are embedded, not pointers,
* for convenience. This structure need not be visible externally.
*
* It is allocated and initialized during mount, and released
* during unmount.
*/
struct rpcrdma_xprt {
struct rpc_xprt xprt;
struct rpcrdma_ia rx_ia;
struct rpcrdma_ep rx_ep;
struct rpcrdma_buffer rx_buf;
struct rpcrdma_create_data_internal rx_data;
struct delayed_work rdma_connect;
struct rpcrdma_stats rx_stats;
};
#define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, xprt)
#define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data)
/*
* Interface Adapter calls - xprtrdma/verbs.c
*/
int rpcrdma_ia_open(struct rpcrdma_xprt *, struct sockaddr *, int);
void rpcrdma_ia_close(struct rpcrdma_ia *);
/*
* Endpoint calls - xprtrdma/verbs.c
*/
int rpcrdma_ep_create(struct rpcrdma_ep *, struct rpcrdma_ia *,
struct rpcrdma_create_data_internal *);
int rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *);
int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *);
int rpcrdma_ep_disconnect(struct rpcrdma_ep *, struct rpcrdma_ia *);
int rpcrdma_ep_post(struct rpcrdma_ia *, struct rpcrdma_ep *,
struct rpcrdma_req *);
int rpcrdma_ep_post_recv(struct rpcrdma_ia *, struct rpcrdma_ep *,
struct rpcrdma_rep *);
/*
* Buffer calls - xprtrdma/verbs.c
*/
int rpcrdma_buffer_create(struct rpcrdma_buffer *, struct rpcrdma_ep *,
struct rpcrdma_ia *,
struct rpcrdma_create_data_internal *);
void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
struct rpcrdma_req *rpcrdma_buffer_get(struct rpcrdma_buffer *);
void rpcrdma_buffer_put(struct rpcrdma_req *);
void rpcrdma_recv_buffer_get(struct rpcrdma_req *);
void rpcrdma_recv_buffer_put(struct rpcrdma_rep *);
int rpcrdma_register_internal(struct rpcrdma_ia *, void *, int,
struct ib_mr **, struct ib_sge *);
int rpcrdma_deregister_internal(struct rpcrdma_ia *,
struct ib_mr *, struct ib_sge *);
int rpcrdma_register_external(struct rpcrdma_mr_seg *,
int, int, struct rpcrdma_xprt *);
int rpcrdma_deregister_external(struct rpcrdma_mr_seg *,
struct rpcrdma_xprt *, void *);
/*
* RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c
*/
void rpcrdma_conn_func(struct rpcrdma_ep *);
void rpcrdma_reply_handler(struct rpcrdma_rep *);
/*
* RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
*/
int rpcrdma_marshal_req(struct rpc_rqst *);
#endif /* _LINUX_SUNRPC_XPRT_RDMA_H */