net/sunrpc/backchannel_rqst.c

12 #include <linux/sunrpc/xprt.h>
22 unsigned int xprt_bc_max_slots(struct rpc_xprt *xprt)
31 static inline int xprt_need_to_requeue(struct rpc_xprt *xprt)
33 	return xprt->bc_alloc_count < xprt->bc_alloc_max;
75 static struct rpc_rqst *xprt_alloc_bc_req(struct rpc_xprt *xprt)
85 	req->rq_xprt = xprt;
123 int xprt_setup_backchannel(struct rpc_xprt *xprt, unsigned int min_reqs)
125 	if (!xprt->ops->bc_setup)
127 	return xprt->ops->bc_setup(xprt, min_reqs);
131 int xprt_setup_bc(struct rpc_xprt *xprt, unsigned int min_reqs)
153 		req = xprt_alloc_bc_req(xprt);
167 	spin_lock(&xprt->bc_pa_lock);
168 	list_splice(&tmp_list, &xprt->bc_pa_list);
169 	xprt->bc_alloc_count += min_reqs;
170 	xprt->bc_alloc_max += min_reqs;
171 	atomic_add(min_reqs, &xprt->bc_slot_count);
172 	spin_unlock(&xprt->bc_pa_lock);
195  * @xprt:	the transport holding the preallocated strucures
202 void xprt_destroy_backchannel(struct rpc_xprt *xprt, unsigned int max_reqs)
204 	if (xprt->ops->bc_destroy)
205 		xprt->ops->bc_destroy(xprt, max_reqs);
209 void xprt_destroy_bc(struct rpc_xprt *xprt, unsigned int max_reqs)
218 	spin_lock_bh(&xprt->bc_pa_lock);
219 	xprt->bc_alloc_max -= min(max_reqs, xprt->bc_alloc_max);
220 	list_for_each_entry_safe(req, tmp, &xprt->bc_pa_list, rq_bc_pa_list) {
224 		xprt->bc_alloc_count--;
225 		atomic_dec(&xprt->bc_slot_count);
229 	spin_unlock_bh(&xprt->bc_pa_lock);
233 		list_empty(&xprt->bc_pa_list) ? "true" : "false");
236 static struct rpc_rqst *xprt_get_bc_request(struct rpc_xprt *xprt, __be32 xid,
242 	if (list_empty(&xprt->bc_pa_list)) {
245 		if (atomic_read(&xprt->bc_slot_count) >= BC_MAX_SLOTS)
247 		list_add_tail(&new->rq_bc_pa_list, &xprt->bc_pa_list);
248 		xprt->bc_alloc_count++;
249 		atomic_inc(&xprt->bc_slot_count);
251 	req = list_first_entry(&xprt->bc_pa_list, struct rpc_rqst,
257 	req->rq_connect_cookie = xprt->connect_cookie;
269 	struct rpc_xprt *xprt = req->rq_xprt;
271 	xprt->ops->bc_free_rqst(req);
276 	struct rpc_xprt *xprt = req->rq_xprt;
280 	req->rq_connect_cookie = xprt->connect_cookie - 1;
289 	spin_lock_bh(&xprt->bc_pa_lock);
290 	if (xprt_need_to_requeue(xprt)) {
294 		list_add_tail(&req->rq_bc_pa_list, &xprt->bc_pa_list);
295 		xprt->bc_alloc_count++;
296 		atomic_inc(&xprt->bc_slot_count);
299 	spin_unlock_bh(&xprt->bc_pa_lock);
310 	xprt_put(xprt);
324 struct rpc_rqst *xprt_lookup_bc_request(struct rpc_xprt *xprt, __be32 xid)
329 		spin_lock(&xprt->bc_pa_lock);
330 		list_for_each_entry(req, &xprt->bc_pa_list, rq_bc_pa_list) {
331 			if (req->rq_connect_cookie != xprt->connect_cookie)
336 		req = xprt_get_bc_request(xprt, xid, new);
338 		spin_unlock(&xprt->bc_pa_lock);
345 		new = xprt_alloc_bc_req(xprt);
356 	struct rpc_xprt *xprt = req->rq_xprt;
357 	struct svc_serv *bc_serv = xprt->bc_serv;
359 	spin_lock(&xprt->bc_pa_lock);
361 	xprt->bc_alloc_count--;
362 	spin_unlock(&xprt->bc_pa_lock);
368 	xprt_get(xprt);