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Diffstat (limited to 'net/sunrpc/xprtrdma/xprt_rdma.h')
| -rw-r--r-- | net/sunrpc/xprtrdma/xprt_rdma.h | 496 |
1 files changed, 496 insertions, 0 deletions
diff --git a/net/sunrpc/xprtrdma/xprt_rdma.h b/net/sunrpc/xprtrdma/xprt_rdma.h new file mode 100644 index 000000000..78e0b8bea --- /dev/null +++ b/net/sunrpc/xprtrdma/xprt_rdma.h @@ -0,0 +1,496 @@ +/* + * 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 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; + 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 rpcrdma_buffer *rr_buffer; + struct rpc_xprt *rr_xprt; + void (*rr_func)(struct rpcrdma_rep *); + 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 rpcrdma_mw { + union { + struct ib_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; + struct rpcrdma_regbuf *rl_sendbuf; + struct rpcrdma_mr_seg rl_segments[RPCRDMA_MAX_SEGS]; +}; + +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); + 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_lock; /* protects indexes */ + u32 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; +}; + +/* + * 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_reset)(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_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 *); + +/* + * 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 *); + +/* 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 */ |