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 <tom@opengridcomputing.com>
This commit is contained in:
Tom Tucker 2008-05-28 13:54:04 -05:00
parent e1441b9a41
commit ab96dddbed
3 changed files with 72 additions and 0 deletions

View file

@ -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;

View file

@ -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 <tom@opengridcomputing.com>");
MODULE_DESCRIPTION("SVC RDMA Transport");

View file

@ -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)
{