[deliverable/linux.git] / net / sunrpc / xprtrdma / xprt_rdma.h

/*
 * 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 <linux/atomic.h>			/* atomic_t, etc */
#include <linux/workqueue.h>		/* struct work_struct */

#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 */
#include <linux/sunrpc/svc.h>		/* RPCSVC_MAXPAYLOAD */

#define RDMA_RESOLVE_TIMEOUT	(5000)	/* 5 seconds */
#define RDMA_CONNECT_RETRY_MAX	(2)	/* retries if no listener backlog */

/*
 * Interface Adapter -- one per transport instance
 */
struct rpcrdma_ia {
	rwlock_t		ri_qplock;
	struct rdma_cm_id 	*ri_id;
	struct ib_pd		*ri_pd;
	struct ib_mr		*ri_bind_mem;
	u32			ri_dma_lkey;
	int			ri_have_dma_lkey;
	struct completion	ri_done;
	int			ri_async_rc;
	enum rpcrdma_memreg	ri_memreg_strategy;
	unsigned int		ri_max_frmr_depth;
};

/*
 * RDMA Endpoint -- one per transport instance
 */

#define RPCRDMA_WC_BUDGET	(128)
#define RPCRDMA_POLLSIZE	(16)

struct rpcrdma_ep {
	atomic_t		rep_cqcount;
	int			rep_cqinit;
	int			rep_connected;
	struct rpcrdma_ia	*rep_ia;
	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;
	struct delayed_work	rep_connect_worker;
	struct ib_wc		rep_send_wcs[RPCRDMA_POLLSIZE];
	struct ib_wc		rep_recv_wcs[RPCRDMA_POLLSIZE];
};

#define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
#define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)

enum rpcrdma_chunktype {
	rpcrdma_noch = 0,
	rpcrdma_readch,
	rpcrdma_areadch,
	rpcrdma_writech,
	rpcrdma_replych
};

/*
 * 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	(64)	/* 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 */
	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_mw - external memory region metadata
 *
 * An external memory region is any buffer or page that is registered
 * on the fly (ie, not pre-registered).
 *
 * Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During
 * call_allocate, rpcrdma_buffer_get() assigns one to each segment in
 * an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep
 * track of registration metadata while each RPC is pending.
 * rpcrdma_deregister_external() uses this metadata to unmap and
 * release these resources when an RPC is complete.
 */
enum rpcrdma_frmr_state {
	FRMR_IS_INVALID,	/* ready to be used */
	FRMR_IS_VALID,		/* in use */
	FRMR_IS_STALE,		/* failed completion */
};

struct rpcrdma_frmr {
	struct ib_fast_reg_page_list	*fr_pgl;
	struct ib_mr			*fr_mr;
	enum rpcrdma_frmr_state		fr_state;
};

struct rpcrdma_mw {
	union {
		struct ib_fmr		*fmr;
		struct rpcrdma_frmr	frmr;
	} r;
	struct list_head	mw_list;
	struct list_head	mw_all;
};

/*
 * 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 *rl_mw;	/* if registered from region */
	} 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 */
	unsigned int	rl_connect_cookie;	/* retry detection */
	enum rpcrdma_chunktype	rl_rtype, rl_wtype;
	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 */
	int		rb_max_requests;/* client max requests */
	struct list_head rb_mws;	/* optional memory windows/fmrs/frmrs */
	struct list_head rb_all;
	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_xprt).inline_rsize)

#define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\
	(rpcx_to_rdmad(rq->rq_xprt).inline_wsize)

#define RPCRDMA_INLINE_PAD_VALUE(rq)\
	rpcx_to_rdmad(rq->rq_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)

/* Setting this to 0 ensures interoperability with early servers.
 * Setting this to 1 enhances certain unaligned read/write performance.
 * Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */
extern int xprt_rdma_pad_optimize;

/*
 * 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 *);
void rpcrdma_ep_destroy(struct rpcrdma_ep *, struct rpcrdma_ia *);
int rpcrdma_ep_connect(struct rpcrdma_ep *, struct rpcrdma_ia *);
void 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 *);

/*
 * RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c
 */
void rpcrdma_connect_worker(struct work_struct *);
void rpcrdma_conn_func(struct rpcrdma_ep *);
void rpcrdma_reply_handler(struct rpcrdma_rep *);

/*
 * RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
 */
ssize_t rpcrdma_marshal_chunks(struct rpc_rqst *, ssize_t);
int rpcrdma_marshal_req(struct rpc_rqst *);
size_t rpcrdma_max_payload(struct rpcrdma_xprt *);

/* Temporary NFS request map cache. Created in svc_rdma.c  */
extern struct kmem_cache *svc_rdma_map_cachep;
/* WR context cache. Created in svc_rdma.c  */
extern struct kmem_cache *svc_rdma_ctxt_cachep;
/* Workqueue created in svc_rdma.c */
extern struct workqueue_struct *svc_rdma_wq;

#if RPCSVC_MAXPAYLOAD < (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT)
#define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD
#else
#define RPCSVC_MAXPAYLOAD_RDMA (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT)
#endif

#endif				/* _LINUX_SUNRPC_XPRT_RDMA_H */
Commit	Line	Data
f58851e6 TT	1	/*
	2	* Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
	3	*
	4	* This software is available to you under a choice of one of two
	5	* licenses. You may choose to be licensed under the terms of the GNU
	6	* General Public License (GPL) Version 2, available from the file
	7	* COPYING in the main directory of this source tree, or the BSD-type
	8	* license below:
	9	*
	10	* Redistribution and use in source and binary forms, with or without
	11	* modification, are permitted provided that the following conditions
	12	* are met:
	13	*
	14	* Redistributions of source code must retain the above copyright
	15	* notice, this list of conditions and the following disclaimer.
	16	*
	17	* Redistributions in binary form must reproduce the above
	18	* copyright notice, this list of conditions and the following
	19	* disclaimer in the documentation and/or other materials provided
	20	* with the distribution.
	21	*
	22	* Neither the name of the Network Appliance, Inc. nor the names of
	23	* its contributors may be used to endorse or promote products
	24	* derived from this software without specific prior written
	25	* permission.
	26	*
	27	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	28	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	29	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	30	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	31	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	32	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	33	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	34	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	35	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	36	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	37	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	38	*/
	39
	40	#ifndef _LINUX_SUNRPC_XPRT_RDMA_H
	41	#define _LINUX_SUNRPC_XPRT_RDMA_H
	42
	43	#include <linux/wait.h> /* wait_queue_head_t, etc */
	44	#include <linux/spinlock.h> /* spinlock_t, etc */
60063497	45	#include <linux/atomic.h> /* atomic_t, etc */
254f91e2	46	#include <linux/workqueue.h> /* struct work_struct */
f58851e6 TT	47
	48	#include <rdma/rdma_cm.h> /* RDMA connection api */
	49	#include <rdma/ib_verbs.h> /* RDMA verbs api */
	50
	51	#include <linux/sunrpc/clnt.h> /* rpc_xprt */
	52	#include <linux/sunrpc/rpc_rdma.h> /* RPC/RDMA protocol */
	53	#include <linux/sunrpc/xprtrdma.h> /* xprt parameters */
7e5be288	54	#include <linux/sunrpc/svc.h> /* RPCSVC_MAXPAYLOAD */
f58851e6	55
5675add3 TT	56	#define RDMA_RESOLVE_TIMEOUT (5000) /* 5 seconds */
	57	#define RDMA_CONNECT_RETRY_MAX (2) /* retries if no listener backlog */
	58
f58851e6 TT	59	/*
	60	* Interface Adapter -- one per transport instance
	61	*/
	62	struct rpcrdma_ia {
73806c88	63	rwlock_t ri_qplock;
f58851e6 TT	64	struct rdma_cm_id *ri_id;
	65	struct ib_pd *ri_pd;
	66	struct ib_mr *ri_bind_mem;
fe9053b3 TT	67	u32 ri_dma_lkey;
fe9053b3 TT	68	int ri_have_dma_lkey;
f58851e6 TT	69	struct completion ri_done;
	70	int ri_async_rc;
	71	enum rpcrdma_memreg ri_memreg_strategy;
0fc6c4e7	72	unsigned int ri_max_frmr_depth;
f58851e6 TT	73	};
	74
	75	/*
	76	* RDMA Endpoint -- one per transport instance
	77	*/
	78
8301a2c0	79	#define RPCRDMA_WC_BUDGET (128)
1c00dd07 CL	80	#define RPCRDMA_POLLSIZE (16)
1c00dd07 CL	81
f58851e6 TT	82	struct rpcrdma_ep {
	83	atomic_t rep_cqcount;
	84	int rep_cqinit;
	85	int rep_connected;
	86	struct rpcrdma_ia *rep_ia;
f58851e6 TT	87	struct ib_qp_init_attr rep_attr;
	88	wait_queue_head_t rep_connect_wait;
	89	struct ib_sge rep_pad; /* holds zeroed pad */
	90	struct ib_mr rep_pad_mr; / holds zeroed pad */
	91	void (rep_func)(struct rpcrdma_ep );
	92	struct rpc_xprt rep_xprt; / for rep_func */
	93	struct rdma_conn_param rep_remote_cma;
	94	struct sockaddr_storage rep_remote_addr;
254f91e2	95	struct delayed_work rep_connect_worker;
1c00dd07 CL	96	struct ib_wc rep_send_wcs[RPCRDMA_POLLSIZE];
1c00dd07 CL	97	struct ib_wc rep_recv_wcs[RPCRDMA_POLLSIZE];
f58851e6 TT	98	};
	99
	100	#define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
	101	#define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)
	102
6ab59945 CL	103	enum rpcrdma_chunktype {
	104	rpcrdma_noch = 0,
	105	rpcrdma_readch,
	106	rpcrdma_areadch,
	107	rpcrdma_writech,
	108	rpcrdma_replych
	109	};
	110
f58851e6 TT	111	/*
	112	* struct rpcrdma_rep -- this structure encapsulates state required to recv
	113	* and complete a reply, asychronously. It needs several pieces of
	114	* state:
	115	* o recv buffer (posted to provider)
	116	* o ib_sge (also donated to provider)
	117	* o status of reply (length, success or not)
	118	* o bookkeeping state to get run by tasklet (list, etc)
	119	*
	120	* These are allocated during initialization, per-transport instance;
	121	* however, the tasklet execution list itself is global, as it should
	122	* always be pretty short.
	123	*
	124	* N of these are associated with a transport instance, and stored in
	125	* struct rpcrdma_buffer. N is the max number of outstanding requests.
	126	*/
	127
	128	/* temporary static scatter/gather max */
2773395b	129	#define RPCRDMA_MAX_DATA_SEGS (64) /* max scatter/gather */
f58851e6 TT	130	#define RPCRDMA_MAX_SEGS (RPCRDMA_MAX_DATA_SEGS + 2) /* head+tail = 2 */
	131	#define MAX_RPCRDMAHDR (\
	132	/* max supported RPC/RDMA header */ \
	133	sizeof(struct rpcrdma_msg) + (2 * sizeof(u32)) + \
	134	(sizeof(struct rpcrdma_read_chunk) * RPCRDMA_MAX_SEGS) + sizeof(u32))
	135
	136	struct rpcrdma_buffer;
	137
	138	struct rpcrdma_rep {
	139	unsigned int rr_len; /* actual received reply length */
	140	struct rpcrdma_buffer rr_buffer; / home base for this structure */
	141	struct rpc_xprt rr_xprt; / needed for request/reply matching */
	142	void (rr_func)(struct rpcrdma_rep );/* called by tasklet in softint */
	143	struct list_head rr_list; /* tasklet list */
f58851e6 TT	144	struct ib_sge rr_iov; /* for posting */
	145	struct ib_mr rr_handle; / handle for mem in rr_iov */
	146	char rr_base[MAX_RPCRDMAHDR]; /* minimal inline receive buffer */
	147	};
	148
0dbb4108 CL	149	/*
	150	* struct rpcrdma_mw - external memory region metadata
	151	*
	152	* An external memory region is any buffer or page that is registered
	153	* on the fly (ie, not pre-registered).
	154	*
3111d72c	155	* Each rpcrdma_buffer has a list of free MWs anchored in rb_mws. During
0dbb4108 CL	156	* call_allocate, rpcrdma_buffer_get() assigns one to each segment in
	157	* an rpcrdma_req. Then rpcrdma_register_external() grabs these to keep
	158	* track of registration metadata while each RPC is pending.
	159	* rpcrdma_deregister_external() uses this metadata to unmap and
	160	* release these resources when an RPC is complete.
	161	*/
	162	enum rpcrdma_frmr_state {
	163	FRMR_IS_INVALID, /* ready to be used */
	164	FRMR_IS_VALID, /* in use */
9f9d802a	165	FRMR_IS_STALE, /* failed completion */
0dbb4108 CL	166	};
	167
	168	struct rpcrdma_frmr {
	169	struct ib_fast_reg_page_list *fr_pgl;
	170	struct ib_mr *fr_mr;
	171	enum rpcrdma_frmr_state fr_state;
	172	};
	173
	174	struct rpcrdma_mw {
	175	union {
	176	struct ib_fmr *fmr;
	177	struct rpcrdma_frmr frmr;
	178	} r;
	179	struct list_head mw_list;
3111d72c	180	struct list_head mw_all;
0dbb4108 CL	181	};
0dbb4108 CL	182
f58851e6 TT	183	/*
	184	* struct rpcrdma_req -- structure central to the request/reply sequence.
	185	*
	186	* N of these are associated with a transport instance, and stored in
	187	* struct rpcrdma_buffer. N is the max number of outstanding requests.
	188	*
	189	* It includes pre-registered buffer memory for send AND recv.
	190	* The recv buffer, however, is not owned by this structure, and
	191	* is "donated" to the hardware when a recv is posted. When a
	192	* reply is handled, the recv buffer used is given back to the
	193	* struct rpcrdma_req associated with the request.
	194	*
	195	* In addition to the basic memory, this structure includes an array
	196	* of iovs for send operations. The reason is that the iovs passed to
	197	* ib_post_{send,recv} must not be modified until the work request
	198	* completes.
	199	*
	200	* NOTES:
	201	* o RPCRDMA_MAX_SEGS is the max number of addressible chunk elements we
	202	* marshal. The number needed varies depending on the iov lists that
	203	* are passed to us, the memory registration mode we are in, and if
	204	* physical addressing is used, the layout.
	205	*/
	206
	207	struct rpcrdma_mr_seg { /* chunk descriptors */
	208	union { /* chunk memory handles */
	209	struct ib_mr rl_mr; / if registered directly */
0dbb4108	210	struct rpcrdma_mw rl_mw; / if registered from region */
f58851e6 TT	211	} mr_chunk;
	212	u64 mr_base; /* registration result */
	213	u32 mr_rkey; /* registration result */
	214	u32 mr_len; /* length of chunk or segment */
	215	int mr_nsegs; /* number of segments in chunk or 0 */
	216	enum dma_data_direction mr_dir; /* segment mapping direction */
	217	dma_addr_t mr_dma; /* segment mapping address */
	218	size_t mr_dmalen; /* segment mapping length */
	219	struct page mr_page; / owning page, if any */
	220	char mr_offset; / kva if no page, else offset */
	221	};
	222
	223	struct rpcrdma_req {
	224	size_t rl_size; /* actual length of buffer */
	225	unsigned int rl_niovs; /* 0, 2 or 4 */
	226	unsigned int rl_nchunks; /* non-zero if chunks */
575448bd	227	unsigned int rl_connect_cookie; /* retry detection */
6ab59945	228	enum rpcrdma_chunktype rl_rtype, rl_wtype;
f58851e6 TT	229	struct rpcrdma_buffer rl_buffer; / home base for this structure */
	230	struct rpcrdma_rep rl_reply;/ holder for reply buffer */
	231	struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];/* chunk segments */
	232	struct ib_sge rl_send_iov[4]; /* for active requests */
	233	struct ib_sge rl_iov; /* for posting */
	234	struct ib_mr rl_handle; / handle for mem in rl_iov */
	235	char rl_base[MAX_RPCRDMAHDR]; /* start of actual buffer */
	236	__u32 rl_xdr_buf[0]; /* start of returned rpc rq_buffer */
	237	};
	238	#define rpcr_to_rdmar(r) \
	239	container_of((r)->rq_buffer, struct rpcrdma_req, rl_xdr_buf[0])
	240
	241	/*
	242	* struct rpcrdma_buffer -- holds list/queue of pre-registered memory for
	243	* inline requests/replies, and client/server credits.
	244	*
	245	* One of these is associated with a transport instance
	246	*/
	247	struct rpcrdma_buffer {
	248	spinlock_t rb_lock; /* protects indexes */
	249	atomic_t rb_credits; /* most recent server credits */
f58851e6	250	int rb_max_requests;/* client max requests */
fe9053b3	251	struct list_head rb_mws; /* optional memory windows/fmrs/frmrs */
3111d72c	252	struct list_head rb_all;
f58851e6 TT	253	int rb_send_index;
	254	struct rpcrdma_req **rb_send_bufs;
	255	int rb_recv_index;
	256	struct rpcrdma_rep **rb_recv_bufs;
	257	char *rb_pool;
	258	};
	259	#define rdmab_to_ia(b) (&container_of((b), struct rpcrdma_xprt, rx_buf)->rx_ia)
	260
	261	/*
	262	* Internal structure for transport instance creation. This
	263	* exists primarily for modularity.
	264	*
	265	* This data should be set with mount options
	266	*/
	267	struct rpcrdma_create_data_internal {
	268	struct sockaddr_storage addr; /* RDMA server address */
	269	unsigned int max_requests; /* max requests (slots) in flight */
	270	unsigned int rsize; /* mount rsize - max read hdr+data */
	271	unsigned int wsize; /* mount wsize - max write hdr+data */
	272	unsigned int inline_rsize; /* max non-rdma read data payload */
	273	unsigned int inline_wsize; /* max non-rdma write data payload */
	274	unsigned int padding; /* non-rdma write header padding */
	275	};
	276
	277	#define RPCRDMA_INLINE_READ_THRESHOLD(rq) \
a4f0835c	278	(rpcx_to_rdmad(rq->rq_xprt).inline_rsize)
f58851e6 TT	279
f58851e6 TT	280	#define RPCRDMA_INLINE_WRITE_THRESHOLD(rq)\
a4f0835c	281	(rpcx_to_rdmad(rq->rq_xprt).inline_wsize)
f58851e6 TT	282
f58851e6 TT	283	#define RPCRDMA_INLINE_PAD_VALUE(rq)\
a4f0835c	284	rpcx_to_rdmad(rq->rq_xprt).padding
f58851e6 TT	285
	286	/*
	287	* Statistics for RPCRDMA
	288	*/
	289	struct rpcrdma_stats {
	290	unsigned long read_chunk_count;
	291	unsigned long write_chunk_count;
	292	unsigned long reply_chunk_count;
	293
	294	unsigned long long total_rdma_request;
	295	unsigned long long total_rdma_reply;
	296
	297	unsigned long long pullup_copy_count;
	298	unsigned long long fixup_copy_count;
	299	unsigned long hardway_register_count;
	300	unsigned long failed_marshal_count;
	301	unsigned long bad_reply_count;
	302	};
	303
	304	/*
	305	* RPCRDMA transport -- encapsulates the structures above for
	306	* integration with RPC.
	307	*
	308	* The contained structures are embedded, not pointers,
	309	* for convenience. This structure need not be visible externally.
	310	*
	311	* It is allocated and initialized during mount, and released
	312	* during unmount.
	313	*/
	314	struct rpcrdma_xprt {
	315	struct rpc_xprt xprt;
	316	struct rpcrdma_ia rx_ia;
	317	struct rpcrdma_ep rx_ep;
	318	struct rpcrdma_buffer rx_buf;
	319	struct rpcrdma_create_data_internal rx_data;
	320	struct delayed_work rdma_connect;
	321	struct rpcrdma_stats rx_stats;
	322	};
	323
	324	#define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, xprt)
	325	#define rpcx_to_rdmad(x) (rpcx_to_rdmax(x)->rx_data)
	326
9191ca3b TT	327	/* Setting this to 0 ensures interoperability with early servers.
	328	* Setting this to 1 enhances certain unaligned read/write performance.
	329	* Default is 0, see sysctl entry and rpc_rdma.c rpcrdma_convert_iovs() */
	330	extern int xprt_rdma_pad_optimize;
	331
f58851e6 TT	332	/*
	333	* Interface Adapter calls - xprtrdma/verbs.c
	334	*/
	335	int rpcrdma_ia_open(struct rpcrdma_xprt , struct sockaddr , int);
	336	void rpcrdma_ia_close(struct rpcrdma_ia *);
	337
	338	/*
	339	* Endpoint calls - xprtrdma/verbs.c
	340	*/
	341	int rpcrdma_ep_create(struct rpcrdma_ep , struct rpcrdma_ia ,
	342	struct rpcrdma_create_data_internal *);
7f1d5419	343	void rpcrdma_ep_destroy(struct rpcrdma_ep , struct rpcrdma_ia );
f58851e6	344	int rpcrdma_ep_connect(struct rpcrdma_ep , struct rpcrdma_ia );
282191cb	345	void rpcrdma_ep_disconnect(struct rpcrdma_ep , struct rpcrdma_ia );
f58851e6 TT	346
	347	int rpcrdma_ep_post(struct rpcrdma_ia , struct rpcrdma_ep ,
	348	struct rpcrdma_req *);
	349	int rpcrdma_ep_post_recv(struct rpcrdma_ia , struct rpcrdma_ep ,
	350	struct rpcrdma_rep *);
	351
	352	/*
	353	* Buffer calls - xprtrdma/verbs.c
	354	*/
	355	int rpcrdma_buffer_create(struct rpcrdma_buffer , struct rpcrdma_ep ,
	356	struct rpcrdma_ia *,
	357	struct rpcrdma_create_data_internal *);
	358	void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
	359
	360	struct rpcrdma_req rpcrdma_buffer_get(struct rpcrdma_buffer );
	361	void rpcrdma_buffer_put(struct rpcrdma_req *);
	362	void rpcrdma_recv_buffer_get(struct rpcrdma_req *);
	363	void rpcrdma_recv_buffer_put(struct rpcrdma_rep *);
	364
	365	int rpcrdma_register_internal(struct rpcrdma_ia , void , int,
	366	struct ib_mr *, struct ib_sge );
	367	int rpcrdma_deregister_internal(struct rpcrdma_ia *,
	368	struct ib_mr , struct ib_sge );
	369
	370	int rpcrdma_register_external(struct rpcrdma_mr_seg *,
	371	int, int, struct rpcrdma_xprt *);
	372	int rpcrdma_deregister_external(struct rpcrdma_mr_seg *,
13c9ff8f	373	struct rpcrdma_xprt *);
f58851e6 TT	374
	375	/*
	376	* RPC/RDMA connection management calls - xprtrdma/rpc_rdma.c
	377	*/
254f91e2	378	void rpcrdma_connect_worker(struct work_struct *);
f58851e6 TT	379	void rpcrdma_conn_func(struct rpcrdma_ep *);
	380	void rpcrdma_reply_handler(struct rpcrdma_rep *);
	381
	382	/*
	383	* RPC/RDMA protocol calls - xprtrdma/rpc_rdma.c
	384	*/
6ab59945	385	ssize_t rpcrdma_marshal_chunks(struct rpc_rqst *, ssize_t);
f58851e6	386	int rpcrdma_marshal_req(struct rpc_rqst *);
43e95988	387	size_t rpcrdma_max_payload(struct rpcrdma_xprt *);
f58851e6	388
cec56c8f TT	389	/* Temporary NFS request map cache. Created in svc_rdma.c */
	390	extern struct kmem_cache *svc_rdma_map_cachep;
	391	/* WR context cache. Created in svc_rdma.c */
	392	extern struct kmem_cache *svc_rdma_ctxt_cachep;
	393	/* Workqueue created in svc_rdma.c */
	394	extern struct workqueue_struct *svc_rdma_wq;
	395
7e5be288 SW	396	#if RPCSVC_MAXPAYLOAD < (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT)
	397	#define RPCSVC_MAXPAYLOAD_RDMA RPCSVC_MAXPAYLOAD
	398	#else
	399	#define RPCSVC_MAXPAYLOAD_RDMA (RPCRDMA_MAX_DATA_SEGS << PAGE_SHIFT)
	400	#endif
	401
f58851e6	402	#endif /* _LINUX_SUNRPC_XPRT_RDMA_H */