From ab96dddbedf4bb8a7a0fe44012efc1d99598c36f Mon Sep 17 00:00:00 2001 From: Tom Tucker Date: Wed, 28 May 2008 13:54:04 -0500 Subject: [PATCH] svcrdma: Add a type for keeping NFS RPC mapping Create a new data structure to hold the remote client address space to local server address space mapping. Signed-off-by: Tom Tucker --- include/linux/sunrpc/svc_rdma.h | 27 ++++++++++++++++++++++++ net/sunrpc/xprtrdma/svc_rdma.c | 19 +++++++++++++++++ net/sunrpc/xprtrdma/svc_rdma_transport.c | 26 +++++++++++++++++++++++ 3 files changed, 72 insertions(+) diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index 05eb4664d0..bd8749cc80 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -86,6 +86,31 @@ struct svc_rdma_op_ctxt { struct page *pages[RPCSVC_MAXPAGES]; }; +/* + * NFS_ requests are mapped on the client side by the chunk lists in + * the RPCRDMA header. During the fetching of the RPC from the client + * and the writing of the reply to the client, the memory in the + * client and the memory in the server must be mapped as contiguous + * vaddr/len for access by the hardware. These data strucures keep + * these mappings. + * + * For an RDMA_WRITE, the 'sge' maps the RPC REPLY. For RDMA_READ, the + * 'sge' in the svc_rdma_req_map maps the server side RPC reply and the + * 'ch' field maps the read-list of the RPCRDMA header to the 'sge' + * mapping of the reply. + */ +struct svc_rdma_chunk_sge { + int start; /* sge no for this chunk */ + int count; /* sge count for this chunk */ +}; +struct svc_rdma_req_map { + unsigned long count; + union { + struct kvec sge[RPCSVC_MAXPAGES]; + struct svc_rdma_chunk_sge ch[RPCSVC_MAXPAGES]; + }; +}; + #define RDMACTXT_F_LAST_CTXT 2 struct svcxprt_rdma { @@ -173,6 +198,8 @@ extern int svc_rdma_post_recv(struct svcxprt_rdma *); extern int svc_rdma_create_listen(struct svc_serv *, int, struct sockaddr *); extern struct svc_rdma_op_ctxt *svc_rdma_get_context(struct svcxprt_rdma *); extern void svc_rdma_put_context(struct svc_rdma_op_ctxt *, int); +extern struct svc_rdma_req_map *svc_rdma_get_req_map(void); +extern void svc_rdma_put_req_map(struct svc_rdma_req_map *); extern void svc_sq_reap(struct svcxprt_rdma *); extern void svc_rq_reap(struct svcxprt_rdma *); extern struct svc_xprt_class svc_rdma_class; diff --git a/net/sunrpc/xprtrdma/svc_rdma.c b/net/sunrpc/xprtrdma/svc_rdma.c index 88c0ca20bb..171f2053e9 100644 --- a/net/sunrpc/xprtrdma/svc_rdma.c +++ b/net/sunrpc/xprtrdma/svc_rdma.c @@ -69,6 +69,9 @@ atomic_t rdma_stat_rq_prod; atomic_t rdma_stat_sq_poll; atomic_t rdma_stat_sq_prod; +/* Temporary NFS request map cache */ +struct kmem_cache *svc_rdma_map_cachep; + /* * This function implements reading and resetting an atomic_t stat * variable through read/write to a proc file. Any write to the file @@ -241,6 +244,7 @@ void svc_rdma_cleanup(void) svcrdma_table_header = NULL; } svc_unreg_xprt_class(&svc_rdma_class); + kmem_cache_destroy(svc_rdma_map_cachep); } int svc_rdma_init(void) @@ -255,9 +259,24 @@ int svc_rdma_init(void) svcrdma_table_header = register_sysctl_table(svcrdma_root_table); + /* Create the temporary map cache */ + svc_rdma_map_cachep = kmem_cache_create("svc_rdma_map_cache", + sizeof(struct svc_rdma_req_map), + 0, + SLAB_HWCACHE_ALIGN, + NULL); + if (!svc_rdma_map_cachep) { + printk(KERN_INFO "Could not allocate map cache.\n"); + goto err; + } + /* Register RDMA with the SVC transport switch */ svc_reg_xprt_class(&svc_rdma_class); return 0; + + err: + unregister_sysctl_table(svcrdma_table_header); + return -ENOMEM; } MODULE_AUTHOR("Tom Tucker "); MODULE_DESCRIPTION("SVC RDMA Transport"); diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index e132509d1d..ae90758d8e 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -173,6 +173,32 @@ void svc_rdma_put_context(struct svc_rdma_op_ctxt *ctxt, int free_pages) atomic_dec(&xprt->sc_ctxt_used); } +/* Temporary NFS request map cache. Created in svc_rdma.c */ +extern struct kmem_cache *svc_rdma_map_cachep; + +/* + * Temporary NFS req mappings are shared across all transport + * instances. These are short lived and should be bounded by the number + * of concurrent server threads * depth of the SQ. + */ +struct svc_rdma_req_map *svc_rdma_get_req_map(void) +{ + struct svc_rdma_req_map *map; + while (1) { + map = kmem_cache_alloc(svc_rdma_map_cachep, GFP_KERNEL); + if (map) + break; + schedule_timeout_uninterruptible(msecs_to_jiffies(500)); + } + map->count = 0; + return map; +} + +void svc_rdma_put_req_map(struct svc_rdma_req_map *map) +{ + kmem_cache_free(svc_rdma_map_cachep, map); +} + /* ib_cq event handler */ static void cq_event_handler(struct ib_event *event, void *context) { -- 2.39.2