/*
* 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 */
