linux/net/sunrpc/xprtrdma/xprt_rdma.h

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/*
* 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 {
const struct rpcrdma_memreg_ops *ri_ops;
rwlock_t ri_qplock;
struct ib_device *ri_device;
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;
unsigned int ri_max_frmr_depth;
struct ib_device_attr ri_devattr;
struct ib_qp_attr ri_qp_attr;
struct ib_qp_init_attr ri_qp_init_attr;
};
/*
* 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 ib_qp_init_attr rep_attr;
wait_queue_head_t rep_connect_wait;
struct rpcrdma_regbuf *rep_padbuf;
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];
};
/*
* Force a signaled SEND Work Request every so often,
* in case the provider needs to do some housekeeping.
*/
#define RPCRDMA_MAX_UNSIGNALED_SENDS (32)
#define INIT_CQCOUNT(ep) atomic_set(&(ep)->rep_cqcount, (ep)->rep_cqinit)
#define DECR_CQCOUNT(ep) atomic_sub_return(1, &(ep)->rep_cqcount)
/* Force completion handler to ignore the signal
*/
#define RPCRDMA_IGNORE_COMPLETION (0ULL)
/* Registered buffer -- registered kmalloc'd memory for RDMA SEND/RECV
*
* The below structure appears at the front of a large region of kmalloc'd
* memory, which always starts on a good alignment boundary.
*/
struct rpcrdma_regbuf {
size_t rg_size;
struct rpcrdma_req *rg_owner;
struct ib_mr *rg_mr;
struct ib_sge rg_iov;
__be32 rg_base[0] __attribute__ ((aligned(256)));
};
static inline u64
rdmab_addr(struct rpcrdma_regbuf *rb)
{
return rb->rg_iov.addr;
}
static inline u32
rdmab_length(struct rpcrdma_regbuf *rb)
{
return rb->rg_iov.length;
}
static inline u32
rdmab_lkey(struct rpcrdma_regbuf *rb)
{
return rb->rg_iov.lkey;
}
static inline struct rpcrdma_msg *
rdmab_to_msg(struct rpcrdma_regbuf *rb)
{
return (struct rpcrdma_msg *)rb->rg_base;
}
/*
* 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 */
struct rpcrdma_buffer;
struct rpcrdma_rep {
unsigned int rr_len;
struct ib_device *rr_device;
struct rpcrdma_xprt *rr_rxprt;
struct list_head rr_list;
struct rpcrdma_regbuf *rr_rdmabuf;
};
/*
* 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 work_struct fr_work;
struct rpcrdma_xprt *fr_xprt;
};
struct rpcrdma_fmr {
struct ib_fmr *fmr;
u64 *physaddrs;
};
struct rpcrdma_mw {
union {
struct rpcrdma_fmr fmr;
struct rpcrdma_frmr frmr;
} r;
void (*mw_sendcompletion)(struct ib_wc *);
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 */
struct rpcrdma_mw *rl_mw; /* registered MR */
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 {
unsigned int rl_niovs; /* 0, 2 or 4 */
unsigned int rl_nchunks; /* non-zero if chunks */
unsigned int rl_connect_cookie; /* retry detection */
struct rpcrdma_buffer *rl_buffer; /* home base for this structure */
struct rpcrdma_rep *rl_reply;/* holder for reply buffer */
struct ib_sge rl_send_iov[4]; /* for active requests */
struct rpcrdma_regbuf *rl_rdmabuf;
xprtrdma: Allocate RPC send buffer separately from struct rpcrdma_req Because internal memory registration is an expensive and synchronous operation, xprtrdma pre-registers send and receive buffers at mount time, and then re-uses them for each RPC. A "hardway" allocation is a memory allocation and registration that replaces a send buffer during the processing of an RPC. Hardway must be done if the RPC send buffer is too small to accommodate an RPC's call and reply headers. For xprtrdma, each RPC send buffer is currently part of struct rpcrdma_req so that xprt_rdma_free(), which is passed nothing but the address of an RPC send buffer, can find its matching struct rpcrdma_req and rpcrdma_rep quickly via container_of / offsetof. That means that hardway currently has to replace a whole rpcrmda_req when it replaces an RPC send buffer. This is often a fairly hefty chunk of contiguous memory due to the size of the rl_segments array and the fact that both the send and receive buffers are part of struct rpcrdma_req. Some obscure re-use of fields in rpcrdma_req is done so that xprt_rdma_free() can detect replaced rpcrdma_req structs, and restore the original. This commit breaks apart the RPC send buffer and struct rpcrdma_req so that increasing the size of the rl_segments array does not change the alignment of each RPC send buffer. (Increasing rl_segments is needed to bump up the maximum r/wsize for NFS/RDMA). This change opens up some interesting possibilities for improving the design of xprt_rdma_allocate(). xprt_rdma_allocate() is now the one place where RPC send buffers are allocated or re-allocated, and they are now always left in place by xprt_rdma_free(). A large re-allocation that includes both the rl_segments array and the RPC send buffer is no longer needed. Send buffer re-allocation becomes quite rare. Good send buffer alignment is guaranteed no matter what the size of the rl_segments array is. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-01-22 00:04:08 +08:00
struct rpcrdma_regbuf *rl_sendbuf;
struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS];
};
xprtrdma: Allocate RPC send buffer separately from struct rpcrdma_req Because internal memory registration is an expensive and synchronous operation, xprtrdma pre-registers send and receive buffers at mount time, and then re-uses them for each RPC. A "hardway" allocation is a memory allocation and registration that replaces a send buffer during the processing of an RPC. Hardway must be done if the RPC send buffer is too small to accommodate an RPC's call and reply headers. For xprtrdma, each RPC send buffer is currently part of struct rpcrdma_req so that xprt_rdma_free(), which is passed nothing but the address of an RPC send buffer, can find its matching struct rpcrdma_req and rpcrdma_rep quickly via container_of / offsetof. That means that hardway currently has to replace a whole rpcrmda_req when it replaces an RPC send buffer. This is often a fairly hefty chunk of contiguous memory due to the size of the rl_segments array and the fact that both the send and receive buffers are part of struct rpcrdma_req. Some obscure re-use of fields in rpcrdma_req is done so that xprt_rdma_free() can detect replaced rpcrdma_req structs, and restore the original. This commit breaks apart the RPC send buffer and struct rpcrdma_req so that increasing the size of the rl_segments array does not change the alignment of each RPC send buffer. (Increasing rl_segments is needed to bump up the maximum r/wsize for NFS/RDMA). This change opens up some interesting possibilities for improving the design of xprt_rdma_allocate(). xprt_rdma_allocate() is now the one place where RPC send buffers are allocated or re-allocated, and they are now always left in place by xprt_rdma_free(). A large re-allocation that includes both the rl_segments array and the RPC send buffer is no longer needed. Send buffer re-allocation becomes quite rare. Good send buffer alignment is guaranteed no matter what the size of the rl_segments array is. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-01-22 00:04:08 +08:00
static inline struct rpcrdma_req *
rpcr_to_rdmar(struct rpc_rqst *rqst)
{
void *buffer = rqst->rq_buffer;
struct rpcrdma_regbuf *rb;
rb = container_of(buffer, struct rpcrdma_regbuf, rg_base);
xprtrdma: Allocate RPC send buffer separately from struct rpcrdma_req Because internal memory registration is an expensive and synchronous operation, xprtrdma pre-registers send and receive buffers at mount time, and then re-uses them for each RPC. A "hardway" allocation is a memory allocation and registration that replaces a send buffer during the processing of an RPC. Hardway must be done if the RPC send buffer is too small to accommodate an RPC's call and reply headers. For xprtrdma, each RPC send buffer is currently part of struct rpcrdma_req so that xprt_rdma_free(), which is passed nothing but the address of an RPC send buffer, can find its matching struct rpcrdma_req and rpcrdma_rep quickly via container_of / offsetof. That means that hardway currently has to replace a whole rpcrmda_req when it replaces an RPC send buffer. This is often a fairly hefty chunk of contiguous memory due to the size of the rl_segments array and the fact that both the send and receive buffers are part of struct rpcrdma_req. Some obscure re-use of fields in rpcrdma_req is done so that xprt_rdma_free() can detect replaced rpcrdma_req structs, and restore the original. This commit breaks apart the RPC send buffer and struct rpcrdma_req so that increasing the size of the rl_segments array does not change the alignment of each RPC send buffer. (Increasing rl_segments is needed to bump up the maximum r/wsize for NFS/RDMA). This change opens up some interesting possibilities for improving the design of xprt_rdma_allocate(). xprt_rdma_allocate() is now the one place where RPC send buffers are allocated or re-allocated, and they are now always left in place by xprt_rdma_free(). A large re-allocation that includes both the rl_segments array and the RPC send buffer is no longer needed. Send buffer re-allocation becomes quite rare. Good send buffer alignment is guaranteed no matter what the size of the rl_segments array is. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2015-01-22 00:04:08 +08:00
return rb->rg_owner;
}
/*
* 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_mwlock; /* protect rb_mws list */
struct list_head rb_mws;
struct list_head rb_all;
char *rb_pool;
spinlock_t rb_lock; /* protect buf arrays */
u32 rb_max_requests;
int rb_send_index;
int rb_recv_index;
struct rpcrdma_req **rb_send_bufs;
struct rpcrdma_rep **rb_recv_bufs;
};
#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;
};
/*
* Per-registration mode operations
*/
struct rpcrdma_xprt;
struct rpcrdma_memreg_ops {
int (*ro_map)(struct rpcrdma_xprt *,
struct rpcrdma_mr_seg *, int, bool);
int (*ro_unmap)(struct rpcrdma_xprt *,
struct rpcrdma_mr_seg *);
int (*ro_open)(struct rpcrdma_ia *,
struct rpcrdma_ep *,
struct rpcrdma_create_data_internal *);
size_t (*ro_maxpages)(struct rpcrdma_xprt *);
int (*ro_init)(struct rpcrdma_xprt *);
void (*ro_destroy)(struct rpcrdma_buffer *);
const char *ro_displayname;
};
extern const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops;
extern const struct rpcrdma_memreg_ops rpcrdma_frwr_memreg_ops;
extern const struct rpcrdma_memreg_ops rpcrdma_physical_memreg_ops;
/*
* 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 rx_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 rx_connect_worker;
struct rpcrdma_stats rx_stats;
};
#define rpcx_to_rdmax(x) container_of(x, struct rpcrdma_xprt, rx_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_xprt *);
void rpcrdma_buffer_destroy(struct rpcrdma_buffer *);
struct rpcrdma_mw *rpcrdma_get_mw(struct rpcrdma_xprt *);
void rpcrdma_put_mw(struct rpcrdma_xprt *, struct rpcrdma_mw *);
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 *);
struct rpcrdma_regbuf *rpcrdma_alloc_regbuf(struct rpcrdma_ia *,
size_t, gfp_t);
void rpcrdma_free_regbuf(struct rpcrdma_ia *,
struct rpcrdma_regbuf *);
unsigned int rpcrdma_max_segments(struct rpcrdma_xprt *);
int frwr_alloc_recovery_wq(void);
void frwr_destroy_recovery_wq(void);
/*
* Wrappers for chunk registration, shared by read/write chunk code.
*/
void rpcrdma_mapping_error(struct rpcrdma_mr_seg *);
static inline enum dma_data_direction
rpcrdma_data_dir(bool writing)
{
return writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
}
static inline void
rpcrdma_map_one(struct ib_device *device, struct rpcrdma_mr_seg *seg,
enum dma_data_direction direction)
{
seg->mr_dir = direction;
seg->mr_dmalen = seg->mr_len;
if (seg->mr_page)
seg->mr_dma = ib_dma_map_page(device,
seg->mr_page, offset_in_page(seg->mr_offset),
seg->mr_dmalen, seg->mr_dir);
else
seg->mr_dma = ib_dma_map_single(device,
seg->mr_offset,
seg->mr_dmalen, seg->mr_dir);
if (ib_dma_mapping_error(device, seg->mr_dma))
rpcrdma_mapping_error(seg);
}
static inline void
rpcrdma_unmap_one(struct ib_device *device, struct rpcrdma_mr_seg *seg)
{
if (seg->mr_page)
ib_dma_unmap_page(device,
seg->mr_dma, seg->mr_dmalen, seg->mr_dir);
else
ib_dma_unmap_single(device,
seg->mr_dma, seg->mr_dmalen, seg->mr_dir);
}
/*
* 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
*/
int rpcrdma_marshal_req(struct rpc_rqst *);
/* RPC/RDMA module init - xprtrdma/transport.c
*/
int xprt_rdma_init(void);
void xprt_rdma_cleanup(void);
/* 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;
#endif /* _LINUX_SUNRPC_XPRT_RDMA_H */