diff options
Diffstat (limited to 'kernel/drivers/staging/lustre/lustre/ptlrpc/client.c')
| -rw-r--r-- | kernel/drivers/staging/lustre/lustre/ptlrpc/client.c | 3149 |
1 files changed, 3149 insertions, 0 deletions
diff --git a/kernel/drivers/staging/lustre/lustre/ptlrpc/client.c b/kernel/drivers/staging/lustre/lustre/ptlrpc/client.c new file mode 100644 index 000000000..0357f1d45 --- /dev/null +++ b/kernel/drivers/staging/lustre/lustre/ptlrpc/client.c @@ -0,0 +1,3149 @@ +/* + * GPL HEADER START + * + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). + * + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved. + * Use is subject to license terms. + * + * Copyright (c) 2011, 2012, Intel Corporation. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. + */ + +/** Implementation of client-side PortalRPC interfaces */ + +#define DEBUG_SUBSYSTEM S_RPC + +#include "../include/obd_support.h" +#include "../include/obd_class.h" +#include "../include/lustre_lib.h" +#include "../include/lustre_ha.h" +#include "../include/lustre_import.h" +#include "../include/lustre_req_layout.h" + +#include "ptlrpc_internal.h" + +static int ptlrpc_send_new_req(struct ptlrpc_request *req); +static int ptlrpcd_check_work(struct ptlrpc_request *req); + +/** + * Initialize passed in client structure \a cl. + */ +void ptlrpc_init_client(int req_portal, int rep_portal, char *name, + struct ptlrpc_client *cl) +{ + cl->cli_request_portal = req_portal; + cl->cli_reply_portal = rep_portal; + cl->cli_name = name; +} +EXPORT_SYMBOL(ptlrpc_init_client); + +/** + * Return PortalRPC connection for remote uud \a uuid + */ +struct ptlrpc_connection *ptlrpc_uuid_to_connection(struct obd_uuid *uuid) +{ + struct ptlrpc_connection *c; + lnet_nid_t self; + lnet_process_id_t peer; + int err; + + /* ptlrpc_uuid_to_peer() initializes its 2nd parameter + * before accessing its values. */ + /* coverity[uninit_use_in_call] */ + err = ptlrpc_uuid_to_peer(uuid, &peer, &self); + if (err != 0) { + CNETERR("cannot find peer %s!\n", uuid->uuid); + return NULL; + } + + c = ptlrpc_connection_get(peer, self, uuid); + if (c) { + memcpy(c->c_remote_uuid.uuid, + uuid->uuid, sizeof(c->c_remote_uuid.uuid)); + } + + CDEBUG(D_INFO, "%s -> %p\n", uuid->uuid, c); + + return c; +} +EXPORT_SYMBOL(ptlrpc_uuid_to_connection); + +/** + * Allocate and initialize new bulk descriptor on the sender. + * Returns pointer to the descriptor or NULL on error. + */ +struct ptlrpc_bulk_desc *ptlrpc_new_bulk(unsigned npages, unsigned max_brw, + unsigned type, unsigned portal) +{ + struct ptlrpc_bulk_desc *desc; + int i; + + OBD_ALLOC(desc, offsetof(struct ptlrpc_bulk_desc, bd_iov[npages])); + if (!desc) + return NULL; + + spin_lock_init(&desc->bd_lock); + init_waitqueue_head(&desc->bd_waitq); + desc->bd_max_iov = npages; + desc->bd_iov_count = 0; + desc->bd_portal = portal; + desc->bd_type = type; + desc->bd_md_count = 0; + LASSERT(max_brw > 0); + desc->bd_md_max_brw = min(max_brw, PTLRPC_BULK_OPS_COUNT); + /* PTLRPC_BULK_OPS_COUNT is the compile-time transfer limit for this + * node. Negotiated ocd_brw_size will always be <= this number. */ + for (i = 0; i < PTLRPC_BULK_OPS_COUNT; i++) + LNetInvalidateHandle(&desc->bd_mds[i]); + + return desc; +} + +/** + * Prepare bulk descriptor for specified outgoing request \a req that + * can fit \a npages * pages. \a type is bulk type. \a portal is where + * the bulk to be sent. Used on client-side. + * Returns pointer to newly allocated initialized bulk descriptor or NULL on + * error. + */ +struct ptlrpc_bulk_desc *ptlrpc_prep_bulk_imp(struct ptlrpc_request *req, + unsigned npages, unsigned max_brw, + unsigned type, unsigned portal) +{ + struct obd_import *imp = req->rq_import; + struct ptlrpc_bulk_desc *desc; + + LASSERT(type == BULK_PUT_SINK || type == BULK_GET_SOURCE); + desc = ptlrpc_new_bulk(npages, max_brw, type, portal); + if (desc == NULL) + return NULL; + + desc->bd_import_generation = req->rq_import_generation; + desc->bd_import = class_import_get(imp); + desc->bd_req = req; + + desc->bd_cbid.cbid_fn = client_bulk_callback; + desc->bd_cbid.cbid_arg = desc; + + /* This makes req own desc, and free it when she frees herself */ + req->rq_bulk = desc; + + return desc; +} +EXPORT_SYMBOL(ptlrpc_prep_bulk_imp); + +/** + * Add a page \a page to the bulk descriptor \a desc. + * Data to transfer in the page starts at offset \a pageoffset and + * amount of data to transfer from the page is \a len + */ +void __ptlrpc_prep_bulk_page(struct ptlrpc_bulk_desc *desc, + struct page *page, int pageoffset, int len, int pin) +{ + LASSERT(desc->bd_iov_count < desc->bd_max_iov); + LASSERT(page != NULL); + LASSERT(pageoffset >= 0); + LASSERT(len > 0); + LASSERT(pageoffset + len <= PAGE_CACHE_SIZE); + + desc->bd_nob += len; + + if (pin) + page_cache_get(page); + + ptlrpc_add_bulk_page(desc, page, pageoffset, len); +} +EXPORT_SYMBOL(__ptlrpc_prep_bulk_page); + +/** + * Uninitialize and free bulk descriptor \a desc. + * Works on bulk descriptors both from server and client side. + */ +void __ptlrpc_free_bulk(struct ptlrpc_bulk_desc *desc, int unpin) +{ + int i; + + LASSERT(desc != NULL); + LASSERT(desc->bd_iov_count != LI_POISON); /* not freed already */ + LASSERT(desc->bd_md_count == 0); /* network hands off */ + LASSERT((desc->bd_export != NULL) ^ (desc->bd_import != NULL)); + + sptlrpc_enc_pool_put_pages(desc); + + if (desc->bd_export) + class_export_put(desc->bd_export); + else + class_import_put(desc->bd_import); + + if (unpin) { + for (i = 0; i < desc->bd_iov_count; i++) + page_cache_release(desc->bd_iov[i].kiov_page); + } + + OBD_FREE(desc, offsetof(struct ptlrpc_bulk_desc, + bd_iov[desc->bd_max_iov])); +} +EXPORT_SYMBOL(__ptlrpc_free_bulk); + +/** + * Set server timelimit for this req, i.e. how long are we willing to wait + * for reply before timing out this request. + */ +void ptlrpc_at_set_req_timeout(struct ptlrpc_request *req) +{ + __u32 serv_est; + int idx; + struct imp_at *at; + + LASSERT(req->rq_import); + + if (AT_OFF) { + /* non-AT settings */ + /** + * \a imp_server_timeout means this is reverse import and + * we send (currently only) ASTs to the client and cannot afford + * to wait too long for the reply, otherwise the other client + * (because of which we are sending this request) would + * timeout waiting for us + */ + req->rq_timeout = req->rq_import->imp_server_timeout ? + obd_timeout / 2 : obd_timeout; + } else { + at = &req->rq_import->imp_at; + idx = import_at_get_index(req->rq_import, + req->rq_request_portal); + serv_est = at_get(&at->iat_service_estimate[idx]); + req->rq_timeout = at_est2timeout(serv_est); + } + /* We could get even fancier here, using history to predict increased + loading... */ + + /* Let the server know what this RPC timeout is by putting it in the + reqmsg*/ + lustre_msg_set_timeout(req->rq_reqmsg, req->rq_timeout); +} +EXPORT_SYMBOL(ptlrpc_at_set_req_timeout); + +/* Adjust max service estimate based on server value */ +static void ptlrpc_at_adj_service(struct ptlrpc_request *req, + unsigned int serv_est) +{ + int idx; + unsigned int oldse; + struct imp_at *at; + + LASSERT(req->rq_import); + at = &req->rq_import->imp_at; + + idx = import_at_get_index(req->rq_import, req->rq_request_portal); + /* max service estimates are tracked on the server side, + so just keep minimal history here */ + oldse = at_measured(&at->iat_service_estimate[idx], serv_est); + if (oldse != 0) + CDEBUG(D_ADAPTTO, "The RPC service estimate for %s ptl %d has changed from %d to %d\n", + req->rq_import->imp_obd->obd_name, req->rq_request_portal, + oldse, at_get(&at->iat_service_estimate[idx])); +} + +/* Expected network latency per remote node (secs) */ +int ptlrpc_at_get_net_latency(struct ptlrpc_request *req) +{ + return AT_OFF ? 0 : at_get(&req->rq_import->imp_at.iat_net_latency); +} + +/* Adjust expected network latency */ +static void ptlrpc_at_adj_net_latency(struct ptlrpc_request *req, + unsigned int service_time) +{ + unsigned int nl, oldnl; + struct imp_at *at; + time_t now = get_seconds(); + + LASSERT(req->rq_import); + + if (service_time > now - req->rq_sent + 3) { + /* bz16408, however, this can also happen if early reply + * is lost and client RPC is expired and resent, early reply + * or reply of original RPC can still be fit in reply buffer + * of resent RPC, now client is measuring time from the + * resent time, but server sent back service time of original + * RPC. + */ + CDEBUG((lustre_msg_get_flags(req->rq_reqmsg) & MSG_RESENT) ? + D_ADAPTTO : D_WARNING, + "Reported service time %u > total measured time " + CFS_DURATION_T"\n", service_time, + cfs_time_sub(now, req->rq_sent)); + return; + } + + /* Network latency is total time less server processing time */ + nl = max_t(int, now - req->rq_sent - + service_time, 0) + 1; /* st rounding */ + at = &req->rq_import->imp_at; + + oldnl = at_measured(&at->iat_net_latency, nl); + if (oldnl != 0) + CDEBUG(D_ADAPTTO, "The network latency for %s (nid %s) has changed from %d to %d\n", + req->rq_import->imp_obd->obd_name, + obd_uuid2str( + &req->rq_import->imp_connection->c_remote_uuid), + oldnl, at_get(&at->iat_net_latency)); +} + +static int unpack_reply(struct ptlrpc_request *req) +{ + int rc; + + if (SPTLRPC_FLVR_POLICY(req->rq_flvr.sf_rpc) != SPTLRPC_POLICY_NULL) { + rc = ptlrpc_unpack_rep_msg(req, req->rq_replen); + if (rc) { + DEBUG_REQ(D_ERROR, req, "unpack_rep failed: %d", rc); + return -EPROTO; + } + } + + rc = lustre_unpack_rep_ptlrpc_body(req, MSG_PTLRPC_BODY_OFF); + if (rc) { + DEBUG_REQ(D_ERROR, req, "unpack ptlrpc body failed: %d", rc); + return -EPROTO; + } + return 0; +} + +/** + * Handle an early reply message, called with the rq_lock held. + * If anything goes wrong just ignore it - same as if it never happened + */ +static int ptlrpc_at_recv_early_reply(struct ptlrpc_request *req) +{ + struct ptlrpc_request *early_req; + time_t olddl; + int rc; + + req->rq_early = 0; + spin_unlock(&req->rq_lock); + + rc = sptlrpc_cli_unwrap_early_reply(req, &early_req); + if (rc) { + spin_lock(&req->rq_lock); + return rc; + } + + rc = unpack_reply(early_req); + if (rc == 0) { + /* Expecting to increase the service time estimate here */ + ptlrpc_at_adj_service(req, + lustre_msg_get_timeout(early_req->rq_repmsg)); + ptlrpc_at_adj_net_latency(req, + lustre_msg_get_service_time(early_req->rq_repmsg)); + } + + sptlrpc_cli_finish_early_reply(early_req); + + if (rc != 0) { + spin_lock(&req->rq_lock); + return rc; + } + + /* Adjust the local timeout for this req */ + ptlrpc_at_set_req_timeout(req); + + spin_lock(&req->rq_lock); + olddl = req->rq_deadline; + /* server assumes it now has rq_timeout from when it sent the + * early reply, so client should give it at least that long. */ + req->rq_deadline = get_seconds() + req->rq_timeout + + ptlrpc_at_get_net_latency(req); + + DEBUG_REQ(D_ADAPTTO, req, + "Early reply #%d, new deadline in " CFS_DURATION_T "s (" CFS_DURATION_T "s)", + req->rq_early_count, + cfs_time_sub(req->rq_deadline, get_seconds()), + cfs_time_sub(req->rq_deadline, olddl)); + + return rc; +} + +struct kmem_cache *request_cache; + +int ptlrpc_request_cache_init(void) +{ + request_cache = kmem_cache_create("ptlrpc_cache", + sizeof(struct ptlrpc_request), + 0, SLAB_HWCACHE_ALIGN, NULL); + return request_cache == NULL ? -ENOMEM : 0; +} + +void ptlrpc_request_cache_fini(void) +{ + kmem_cache_destroy(request_cache); +} + +struct ptlrpc_request *ptlrpc_request_cache_alloc(gfp_t flags) +{ + struct ptlrpc_request *req; + + OBD_SLAB_ALLOC_PTR_GFP(req, request_cache, flags); + return req; +} + +void ptlrpc_request_cache_free(struct ptlrpc_request *req) +{ + OBD_SLAB_FREE_PTR(req, request_cache); +} + +/** + * Wind down request pool \a pool. + * Frees all requests from the pool too + */ +void ptlrpc_free_rq_pool(struct ptlrpc_request_pool *pool) +{ + struct list_head *l, *tmp; + struct ptlrpc_request *req; + + LASSERT(pool != NULL); + + spin_lock(&pool->prp_lock); + list_for_each_safe(l, tmp, &pool->prp_req_list) { + req = list_entry(l, struct ptlrpc_request, rq_list); + list_del(&req->rq_list); + LASSERT(req->rq_reqbuf); + LASSERT(req->rq_reqbuf_len == pool->prp_rq_size); + OBD_FREE_LARGE(req->rq_reqbuf, pool->prp_rq_size); + ptlrpc_request_cache_free(req); + } + spin_unlock(&pool->prp_lock); + OBD_FREE(pool, sizeof(*pool)); +} +EXPORT_SYMBOL(ptlrpc_free_rq_pool); + +/** + * Allocates, initializes and adds \a num_rq requests to the pool \a pool + */ +void ptlrpc_add_rqs_to_pool(struct ptlrpc_request_pool *pool, int num_rq) +{ + int i; + int size = 1; + + while (size < pool->prp_rq_size) + size <<= 1; + + LASSERTF(list_empty(&pool->prp_req_list) || + size == pool->prp_rq_size, + "Trying to change pool size with nonempty pool from %d to %d bytes\n", + pool->prp_rq_size, size); + + spin_lock(&pool->prp_lock); + pool->prp_rq_size = size; + for (i = 0; i < num_rq; i++) { + struct ptlrpc_request *req; + struct lustre_msg *msg; + + spin_unlock(&pool->prp_lock); + req = ptlrpc_request_cache_alloc(GFP_NOFS); + if (!req) + return; + OBD_ALLOC_LARGE(msg, size); + if (!msg) { + ptlrpc_request_cache_free(req); + return; + } + req->rq_reqbuf = msg; + req->rq_reqbuf_len = size; + req->rq_pool = pool; + spin_lock(&pool->prp_lock); + list_add_tail(&req->rq_list, &pool->prp_req_list); + } + spin_unlock(&pool->prp_lock); +} +EXPORT_SYMBOL(ptlrpc_add_rqs_to_pool); + +/** + * Create and initialize new request pool with given attributes: + * \a num_rq - initial number of requests to create for the pool + * \a msgsize - maximum message size possible for requests in thid pool + * \a populate_pool - function to be called when more requests need to be added + * to the pool + * Returns pointer to newly created pool or NULL on error. + */ +struct ptlrpc_request_pool * +ptlrpc_init_rq_pool(int num_rq, int msgsize, + void (*populate_pool)(struct ptlrpc_request_pool *, int)) +{ + struct ptlrpc_request_pool *pool; + + OBD_ALLOC(pool, sizeof(struct ptlrpc_request_pool)); + if (!pool) + return NULL; + + /* Request next power of two for the allocation, because internally + kernel would do exactly this */ + + spin_lock_init(&pool->prp_lock); + INIT_LIST_HEAD(&pool->prp_req_list); + pool->prp_rq_size = msgsize + SPTLRPC_MAX_PAYLOAD; + pool->prp_populate = populate_pool; + + populate_pool(pool, num_rq); + + if (list_empty(&pool->prp_req_list)) { + /* have not allocated a single request for the pool */ + OBD_FREE(pool, sizeof(struct ptlrpc_request_pool)); + pool = NULL; + } + return pool; +} +EXPORT_SYMBOL(ptlrpc_init_rq_pool); + +/** + * Fetches one request from pool \a pool + */ +static struct ptlrpc_request * +ptlrpc_prep_req_from_pool(struct ptlrpc_request_pool *pool) +{ + struct ptlrpc_request *request; + struct lustre_msg *reqbuf; + + if (!pool) + return NULL; + + spin_lock(&pool->prp_lock); + + /* See if we have anything in a pool, and bail out if nothing, + * in writeout path, where this matters, this is safe to do, because + * nothing is lost in this case, and when some in-flight requests + * complete, this code will be called again. */ + if (unlikely(list_empty(&pool->prp_req_list))) { + spin_unlock(&pool->prp_lock); + return NULL; + } + + request = list_entry(pool->prp_req_list.next, struct ptlrpc_request, + rq_list); + list_del_init(&request->rq_list); + spin_unlock(&pool->prp_lock); + + LASSERT(request->rq_reqbuf); + LASSERT(request->rq_pool); + + reqbuf = request->rq_reqbuf; + memset(request, 0, sizeof(*request)); + request->rq_reqbuf = reqbuf; + request->rq_reqbuf_len = pool->prp_rq_size; + request->rq_pool = pool; + + return request; +} + +/** + * Returns freed \a request to pool. + */ +static void __ptlrpc_free_req_to_pool(struct ptlrpc_request *request) +{ + struct ptlrpc_request_pool *pool = request->rq_pool; + + spin_lock(&pool->prp_lock); + LASSERT(list_empty(&request->rq_list)); + LASSERT(!request->rq_receiving_reply); + list_add_tail(&request->rq_list, &pool->prp_req_list); + spin_unlock(&pool->prp_lock); +} + +static int __ptlrpc_request_bufs_pack(struct ptlrpc_request *request, + __u32 version, int opcode, + int count, __u32 *lengths, char **bufs, + struct ptlrpc_cli_ctx *ctx) +{ + struct obd_import *imp = request->rq_import; + int rc; + + if (unlikely(ctx)) + request->rq_cli_ctx = sptlrpc_cli_ctx_get(ctx); + else { + rc = sptlrpc_req_get_ctx(request); + if (rc) + goto out_free; + } + + sptlrpc_req_set_flavor(request, opcode); + + rc = lustre_pack_request(request, imp->imp_msg_magic, count, + lengths, bufs); + if (rc) { + LASSERT(!request->rq_pool); + goto out_ctx; + } + + lustre_msg_add_version(request->rq_reqmsg, version); + request->rq_send_state = LUSTRE_IMP_FULL; + request->rq_type = PTL_RPC_MSG_REQUEST; + request->rq_export = NULL; + + request->rq_req_cbid.cbid_fn = request_out_callback; + request->rq_req_cbid.cbid_arg = request; + + request->rq_reply_cbid.cbid_fn = reply_in_callback; + request->rq_reply_cbid.cbid_arg = request; + + request->rq_reply_deadline = 0; + request->rq_phase = RQ_PHASE_NEW; + request->rq_next_phase = RQ_PHASE_UNDEFINED; + + request->rq_request_portal = imp->imp_client->cli_request_portal; + request->rq_reply_portal = imp->imp_client->cli_reply_portal; + + ptlrpc_at_set_req_timeout(request); + + spin_lock_init(&request->rq_lock); + INIT_LIST_HEAD(&request->rq_list); + INIT_LIST_HEAD(&request->rq_timed_list); + INIT_LIST_HEAD(&request->rq_replay_list); + INIT_LIST_HEAD(&request->rq_ctx_chain); + INIT_LIST_HEAD(&request->rq_set_chain); + INIT_LIST_HEAD(&request->rq_history_list); + INIT_LIST_HEAD(&request->rq_exp_list); + init_waitqueue_head(&request->rq_reply_waitq); + init_waitqueue_head(&request->rq_set_waitq); + request->rq_xid = ptlrpc_next_xid(); + atomic_set(&request->rq_refcount, 1); + + lustre_msg_set_opc(request->rq_reqmsg, opcode); + + return 0; +out_ctx: + sptlrpc_cli_ctx_put(request->rq_cli_ctx, 1); +out_free: + class_import_put(imp); + return rc; +} + +int ptlrpc_request_bufs_pack(struct ptlrpc_request *request, + __u32 version, int opcode, char **bufs, + struct ptlrpc_cli_ctx *ctx) +{ + int count; + + count = req_capsule_filled_sizes(&request->rq_pill, RCL_CLIENT); + return __ptlrpc_request_bufs_pack(request, version, opcode, count, + request->rq_pill.rc_area[RCL_CLIENT], + bufs, ctx); +} +EXPORT_SYMBOL(ptlrpc_request_bufs_pack); + +/** + * Pack request buffers for network transfer, performing necessary encryption + * steps if necessary. + */ +int ptlrpc_request_pack(struct ptlrpc_request *request, + __u32 version, int opcode) +{ + int rc; + rc = ptlrpc_request_bufs_pack(request, version, opcode, NULL, NULL); + if (rc) + return rc; + + /* For some old 1.8 clients (< 1.8.7), they will LASSERT the size of + * ptlrpc_body sent from server equal to local ptlrpc_body size, so we + * have to send old ptlrpc_body to keep interoperability with these + * clients. + * + * Only three kinds of server->client RPCs so far: + * - LDLM_BL_CALLBACK + * - LDLM_CP_CALLBACK + * - LDLM_GL_CALLBACK + * + * XXX This should be removed whenever we drop the interoperability with + * the these old clients. + */ + if (opcode == LDLM_BL_CALLBACK || opcode == LDLM_CP_CALLBACK || + opcode == LDLM_GL_CALLBACK) + req_capsule_shrink(&request->rq_pill, &RMF_PTLRPC_BODY, + sizeof(struct ptlrpc_body_v2), RCL_CLIENT); + + return rc; +} +EXPORT_SYMBOL(ptlrpc_request_pack); + +/** + * Helper function to allocate new request on import \a imp + * and possibly using existing request from pool \a pool if provided. + * Returns allocated request structure with import field filled or + * NULL on error. + */ +static inline +struct ptlrpc_request *__ptlrpc_request_alloc(struct obd_import *imp, + struct ptlrpc_request_pool *pool) +{ + struct ptlrpc_request *request = NULL; + + if (pool) + request = ptlrpc_prep_req_from_pool(pool); + + if (!request) + request = ptlrpc_request_cache_alloc(GFP_NOFS); + + if (request) { + LASSERTF((unsigned long)imp > 0x1000, "%p", imp); + LASSERT(imp != LP_POISON); + LASSERTF((unsigned long)imp->imp_client > 0x1000, "%p", + imp->imp_client); + LASSERT(imp->imp_client != LP_POISON); + + request->rq_import = class_import_get(imp); + } else { + CERROR("request allocation out of memory\n"); + } + + return request; +} + +/** + * Helper function for creating a request. + * Calls __ptlrpc_request_alloc to allocate new request structure and inits + * buffer structures according to capsule template \a format. + * Returns allocated request structure pointer or NULL on error. + */ +static struct ptlrpc_request * +ptlrpc_request_alloc_internal(struct obd_import *imp, + struct ptlrpc_request_pool *pool, + const struct req_format *format) +{ + struct ptlrpc_request *request; + + request = __ptlrpc_request_alloc(imp, pool); + if (request == NULL) + return NULL; + + req_capsule_init(&request->rq_pill, request, RCL_CLIENT); + req_capsule_set(&request->rq_pill, format); + return request; +} + +/** + * Allocate new request structure for import \a imp and initialize its + * buffer structure according to capsule template \a format. + */ +struct ptlrpc_request *ptlrpc_request_alloc(struct obd_import *imp, + const struct req_format *format) +{ + return ptlrpc_request_alloc_internal(imp, NULL, format); +} +EXPORT_SYMBOL(ptlrpc_request_alloc); + +/** + * Allocate new request structure for import \a imp from pool \a pool and + * initialize its buffer structure according to capsule template \a format. + */ +struct ptlrpc_request *ptlrpc_request_alloc_pool(struct obd_import *imp, + struct ptlrpc_request_pool *pool, + const struct req_format *format) +{ + return ptlrpc_request_alloc_internal(imp, pool, format); +} +EXPORT_SYMBOL(ptlrpc_request_alloc_pool); + +/** + * For requests not from pool, free memory of the request structure. + * For requests obtained from a pool earlier, return request back to pool. + */ +void ptlrpc_request_free(struct ptlrpc_request *request) +{ + if (request->rq_pool) + __ptlrpc_free_req_to_pool(request); + else + ptlrpc_request_cache_free(request); +} +EXPORT_SYMBOL(ptlrpc_request_free); + +/** + * Allocate new request for operation \a opcode and immediately pack it for + * network transfer. + * Only used for simple requests like OBD_PING where the only important + * part of the request is operation itself. + * Returns allocated request or NULL on error. + */ +struct ptlrpc_request *ptlrpc_request_alloc_pack(struct obd_import *imp, + const struct req_format *format, + __u32 version, int opcode) +{ + struct ptlrpc_request *req = ptlrpc_request_alloc(imp, format); + int rc; + + if (req) { + rc = ptlrpc_request_pack(req, version, opcode); + if (rc) { + ptlrpc_request_free(req); + req = NULL; + } + } + return req; +} +EXPORT_SYMBOL(ptlrpc_request_alloc_pack); + +/** + * Prepare request (fetched from pool \a pool if not NULL) on import \a imp + * for operation \a opcode. Request would contain \a count buffers. + * Sizes of buffers are described in array \a lengths and buffers themselves + * are provided by a pointer \a bufs. + * Returns prepared request structure pointer or NULL on error. + */ +struct ptlrpc_request * +ptlrpc_prep_req_pool(struct obd_import *imp, + __u32 version, int opcode, + int count, __u32 *lengths, char **bufs, + struct ptlrpc_request_pool *pool) +{ + struct ptlrpc_request *request; + int rc; + + request = __ptlrpc_request_alloc(imp, pool); + if (!request) + return NULL; + + rc = __ptlrpc_request_bufs_pack(request, version, opcode, count, + lengths, bufs, NULL); + if (rc) { + ptlrpc_request_free(request); + request = NULL; + } + return request; +} +EXPORT_SYMBOL(ptlrpc_prep_req_pool); + +/** + * Same as ptlrpc_prep_req_pool, but without pool + */ +struct ptlrpc_request * +ptlrpc_prep_req(struct obd_import *imp, __u32 version, int opcode, int count, + __u32 *lengths, char **bufs) +{ + return ptlrpc_prep_req_pool(imp, version, opcode, count, lengths, bufs, + NULL); +} +EXPORT_SYMBOL(ptlrpc_prep_req); + +/** + * Allocate and initialize new request set structure. + * Returns a pointer to the newly allocated set structure or NULL on error. + */ +struct ptlrpc_request_set *ptlrpc_prep_set(void) +{ + struct ptlrpc_request_set *set; + + OBD_ALLOC(set, sizeof(*set)); + if (!set) + return NULL; + atomic_set(&set->set_refcount, 1); + INIT_LIST_HEAD(&set->set_requests); + init_waitqueue_head(&set->set_waitq); + atomic_set(&set->set_new_count, 0); + atomic_set(&set->set_remaining, 0); + spin_lock_init(&set->set_new_req_lock); + INIT_LIST_HEAD(&set->set_new_requests); + INIT_LIST_HEAD(&set->set_cblist); + set->set_max_inflight = UINT_MAX; + set->set_producer = NULL; + set->set_producer_arg = NULL; + set->set_rc = 0; + + return set; +} +EXPORT_SYMBOL(ptlrpc_prep_set); + +/** + * Allocate and initialize new request set structure with flow control + * extension. This extension allows to control the number of requests in-flight + * for the whole set. A callback function to generate requests must be provided + * and the request set will keep the number of requests sent over the wire to + * @max_inflight. + * Returns a pointer to the newly allocated set structure or NULL on error. + */ +struct ptlrpc_request_set *ptlrpc_prep_fcset(int max, set_producer_func func, + void *arg) + +{ + struct ptlrpc_request_set *set; + + set = ptlrpc_prep_set(); + if (!set) + return NULL; + + set->set_max_inflight = max; + set->set_producer = func; + set->set_producer_arg = arg; + + return set; +} +EXPORT_SYMBOL(ptlrpc_prep_fcset); + +/** + * Wind down and free request set structure previously allocated with + * ptlrpc_prep_set. + * Ensures that all requests on the set have completed and removes + * all requests from the request list in a set. + * If any unsent request happen to be on the list, pretends that they got + * an error in flight and calls their completion handler. + */ +void ptlrpc_set_destroy(struct ptlrpc_request_set *set) +{ + struct list_head *tmp; + struct list_head *next; + int expected_phase; + int n = 0; + + /* Requests on the set should either all be completed, or all be new */ + expected_phase = (atomic_read(&set->set_remaining) == 0) ? + RQ_PHASE_COMPLETE : RQ_PHASE_NEW; + list_for_each(tmp, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + + LASSERT(req->rq_phase == expected_phase); + n++; + } + + LASSERTF(atomic_read(&set->set_remaining) == 0 || + atomic_read(&set->set_remaining) == n, "%d / %d\n", + atomic_read(&set->set_remaining), n); + + list_for_each_safe(tmp, next, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + list_del_init(&req->rq_set_chain); + + LASSERT(req->rq_phase == expected_phase); + + if (req->rq_phase == RQ_PHASE_NEW) { + ptlrpc_req_interpret(NULL, req, -EBADR); + atomic_dec(&set->set_remaining); + } + + spin_lock(&req->rq_lock); + req->rq_set = NULL; + req->rq_invalid_rqset = 0; + spin_unlock(&req->rq_lock); + + ptlrpc_req_finished(req); + } + + LASSERT(atomic_read(&set->set_remaining) == 0); + + ptlrpc_reqset_put(set); +} +EXPORT_SYMBOL(ptlrpc_set_destroy); + +/** + * Add a callback function \a fn to the set. + * This function would be called when all requests on this set are completed. + * The function will be passed \a data argument. + */ +int ptlrpc_set_add_cb(struct ptlrpc_request_set *set, + set_interpreter_func fn, void *data) +{ + struct ptlrpc_set_cbdata *cbdata; + + OBD_ALLOC_PTR(cbdata); + if (cbdata == NULL) + return -ENOMEM; + + cbdata->psc_interpret = fn; + cbdata->psc_data = data; + list_add_tail(&cbdata->psc_item, &set->set_cblist); + + return 0; +} +EXPORT_SYMBOL(ptlrpc_set_add_cb); + +/** + * Add a new request to the general purpose request set. + * Assumes request reference from the caller. + */ +void ptlrpc_set_add_req(struct ptlrpc_request_set *set, + struct ptlrpc_request *req) +{ + LASSERT(list_empty(&req->rq_set_chain)); + + /* The set takes over the caller's request reference */ + list_add_tail(&req->rq_set_chain, &set->set_requests); + req->rq_set = set; + atomic_inc(&set->set_remaining); + req->rq_queued_time = cfs_time_current(); + + if (req->rq_reqmsg != NULL) + lustre_msg_set_jobid(req->rq_reqmsg, NULL); + + if (set->set_producer != NULL) + /* If the request set has a producer callback, the RPC must be + * sent straight away */ + ptlrpc_send_new_req(req); +} +EXPORT_SYMBOL(ptlrpc_set_add_req); + +/** + * Add a request to a request with dedicated server thread + * and wake the thread to make any necessary processing. + * Currently only used for ptlrpcd. + */ +void ptlrpc_set_add_new_req(struct ptlrpcd_ctl *pc, + struct ptlrpc_request *req) +{ + struct ptlrpc_request_set *set = pc->pc_set; + int count, i; + + LASSERT(req->rq_set == NULL); + LASSERT(test_bit(LIOD_STOP, &pc->pc_flags) == 0); + + spin_lock(&set->set_new_req_lock); + /* + * The set takes over the caller's request reference. + */ + req->rq_set = set; + req->rq_queued_time = cfs_time_current(); + list_add_tail(&req->rq_set_chain, &set->set_new_requests); + count = atomic_inc_return(&set->set_new_count); + spin_unlock(&set->set_new_req_lock); + + /* Only need to call wakeup once for the first entry. */ + if (count == 1) { + wake_up(&set->set_waitq); + + /* XXX: It maybe unnecessary to wakeup all the partners. But to + * guarantee the async RPC can be processed ASAP, we have + * no other better choice. It maybe fixed in future. */ + for (i = 0; i < pc->pc_npartners; i++) + wake_up(&pc->pc_partners[i]->pc_set->set_waitq); + } +} +EXPORT_SYMBOL(ptlrpc_set_add_new_req); + +/** + * Based on the current state of the import, determine if the request + * can be sent, is an error, or should be delayed. + * + * Returns true if this request should be delayed. If false, and + * *status is set, then the request can not be sent and *status is the + * error code. If false and status is 0, then request can be sent. + * + * The imp->imp_lock must be held. + */ +static int ptlrpc_import_delay_req(struct obd_import *imp, + struct ptlrpc_request *req, int *status) +{ + int delay = 0; + + LASSERT(status != NULL); + *status = 0; + + if (req->rq_ctx_init || req->rq_ctx_fini) { + /* always allow ctx init/fini rpc go through */ + } else if (imp->imp_state == LUSTRE_IMP_NEW) { + DEBUG_REQ(D_ERROR, req, "Uninitialized import."); + *status = -EIO; + } else if (imp->imp_state == LUSTRE_IMP_CLOSED) { + /* pings may safely race with umount */ + DEBUG_REQ(lustre_msg_get_opc(req->rq_reqmsg) == OBD_PING ? + D_HA : D_ERROR, req, "IMP_CLOSED "); + *status = -EIO; + } else if (ptlrpc_send_limit_expired(req)) { + /* probably doesn't need to be a D_ERROR after initial testing */ + DEBUG_REQ(D_ERROR, req, "send limit expired "); + *status = -EIO; + } else if (req->rq_send_state == LUSTRE_IMP_CONNECTING && + imp->imp_state == LUSTRE_IMP_CONNECTING) { + /* allow CONNECT even if import is invalid */ + if (atomic_read(&imp->imp_inval_count) != 0) { + DEBUG_REQ(D_ERROR, req, "invalidate in flight"); + *status = -EIO; + } + } else if (imp->imp_invalid || imp->imp_obd->obd_no_recov) { + if (!imp->imp_deactive) + DEBUG_REQ(D_NET, req, "IMP_INVALID"); + *status = -ESHUTDOWN; /* bz 12940 */ + } else if (req->rq_import_generation != imp->imp_generation) { + DEBUG_REQ(D_ERROR, req, "req wrong generation:"); + *status = -EIO; + } else if (req->rq_send_state != imp->imp_state) { + /* invalidate in progress - any requests should be drop */ + if (atomic_read(&imp->imp_inval_count) != 0) { + DEBUG_REQ(D_ERROR, req, "invalidate in flight"); + *status = -EIO; + } else if (imp->imp_dlm_fake || req->rq_no_delay) { + *status = -EWOULDBLOCK; + } else if (req->rq_allow_replay && + (imp->imp_state == LUSTRE_IMP_REPLAY || + imp->imp_state == LUSTRE_IMP_REPLAY_LOCKS || + imp->imp_state == LUSTRE_IMP_REPLAY_WAIT || + imp->imp_state == LUSTRE_IMP_RECOVER)) { + DEBUG_REQ(D_HA, req, "allow during recovery.\n"); + } else { + delay = 1; + } + } + + return delay; +} + +/** + * Decide if the error message regarding provided request \a req + * should be printed to the console or not. + * Makes it's decision on request status and other properties. + * Returns 1 to print error on the system console or 0 if not. + */ +static int ptlrpc_console_allow(struct ptlrpc_request *req) +{ + __u32 opc; + int err; + + LASSERT(req->rq_reqmsg != NULL); + opc = lustre_msg_get_opc(req->rq_reqmsg); + + /* Suppress particular reconnect errors which are to be expected. No + * errors are suppressed for the initial connection on an import */ + if ((lustre_handle_is_used(&req->rq_import->imp_remote_handle)) && + (opc == OST_CONNECT || opc == MDS_CONNECT || opc == MGS_CONNECT)) { + + /* Suppress timed out reconnect requests */ + if (req->rq_timedout) + return 0; + + /* Suppress unavailable/again reconnect requests */ + err = lustre_msg_get_status(req->rq_repmsg); + if (err == -ENODEV || err == -EAGAIN) + return 0; + } + + return 1; +} + +/** + * Check request processing status. + * Returns the status. + */ +static int ptlrpc_check_status(struct ptlrpc_request *req) +{ + int err; + + err = lustre_msg_get_status(req->rq_repmsg); + if (lustre_msg_get_type(req->rq_repmsg) == PTL_RPC_MSG_ERR) { + struct obd_import *imp = req->rq_import; + __u32 opc = lustre_msg_get_opc(req->rq_reqmsg); + if (ptlrpc_console_allow(req)) + LCONSOLE_ERROR_MSG(0x011, "%s: Communicating with %s, operation %s failed with %d.\n", + imp->imp_obd->obd_name, + libcfs_nid2str( + imp->imp_connection->c_peer.nid), + ll_opcode2str(opc), err); + return err < 0 ? err : -EINVAL; + } + + if (err < 0) { + DEBUG_REQ(D_INFO, req, "status is %d", err); + } else if (err > 0) { + /* XXX: translate this error from net to host */ + DEBUG_REQ(D_INFO, req, "status is %d", err); + } + + return err; +} + +/** + * save pre-versions of objects into request for replay. + * Versions are obtained from server reply. + * used for VBR. + */ +static void ptlrpc_save_versions(struct ptlrpc_request *req) +{ + struct lustre_msg *repmsg = req->rq_repmsg; + struct lustre_msg *reqmsg = req->rq_reqmsg; + __u64 *versions = lustre_msg_get_versions(repmsg); + + if (lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY) + return; + + LASSERT(versions); + lustre_msg_set_versions(reqmsg, versions); + CDEBUG(D_INFO, "Client save versions [%#llx/%#llx]\n", + versions[0], versions[1]); +} + +/** + * Callback function called when client receives RPC reply for \a req. + * Returns 0 on success or error code. + * The return value would be assigned to req->rq_status by the caller + * as request processing status. + * This function also decides if the request needs to be saved for later replay. + */ +static int after_reply(struct ptlrpc_request *req) +{ + struct obd_import *imp = req->rq_import; + struct obd_device *obd = req->rq_import->imp_obd; + int rc; + struct timeval work_start; + long timediff; + + LASSERT(obd != NULL); + /* repbuf must be unlinked */ + LASSERT(!req->rq_receiving_reply && !req->rq_reply_unlink); + + if (req->rq_reply_truncate) { + if (ptlrpc_no_resend(req)) { + DEBUG_REQ(D_ERROR, req, "reply buffer overflow, expected: %d, actual size: %d", + req->rq_nob_received, req->rq_repbuf_len); + return -EOVERFLOW; + } + + sptlrpc_cli_free_repbuf(req); + /* Pass the required reply buffer size (include + * space for early reply). + * NB: no need to roundup because alloc_repbuf + * will roundup it */ + req->rq_replen = req->rq_nob_received; + req->rq_nob_received = 0; + spin_lock(&req->rq_lock); + req->rq_resend = 1; + spin_unlock(&req->rq_lock); + return 0; + } + + /* + * NB Until this point, the whole of the incoming message, + * including buflens, status etc is in the sender's byte order. + */ + rc = sptlrpc_cli_unwrap_reply(req); + if (rc) { + DEBUG_REQ(D_ERROR, req, "unwrap reply failed (%d):", rc); + return rc; + } + + /* + * Security layer unwrap might ask resend this request. + */ + if (req->rq_resend) + return 0; + + rc = unpack_reply(req); + if (rc) + return rc; + + /* retry indefinitely on EINPROGRESS */ + if (lustre_msg_get_status(req->rq_repmsg) == -EINPROGRESS && + ptlrpc_no_resend(req) == 0 && !req->rq_no_retry_einprogress) { + time_t now = get_seconds(); + + DEBUG_REQ(D_RPCTRACE, req, "Resending request on EINPROGRESS"); + spin_lock(&req->rq_lock); + req->rq_resend = 1; + spin_unlock(&req->rq_lock); + req->rq_nr_resend++; + + /* allocate new xid to avoid reply reconstruction */ + if (!req->rq_bulk) { + /* new xid is already allocated for bulk in + * ptlrpc_check_set() */ + req->rq_xid = ptlrpc_next_xid(); + DEBUG_REQ(D_RPCTRACE, req, "Allocating new xid for resend on EINPROGRESS"); + } + + /* Readjust the timeout for current conditions */ + ptlrpc_at_set_req_timeout(req); + /* delay resend to give a chance to the server to get ready. + * The delay is increased by 1s on every resend and is capped to + * the current request timeout (i.e. obd_timeout if AT is off, + * or AT service time x 125% + 5s, see at_est2timeout) */ + if (req->rq_nr_resend > req->rq_timeout) + req->rq_sent = now + req->rq_timeout; + else + req->rq_sent = now + req->rq_nr_resend; + + return 0; + } + + do_gettimeofday(&work_start); + timediff = cfs_timeval_sub(&work_start, &req->rq_arrival_time, NULL); + if (obd->obd_svc_stats != NULL) { + lprocfs_counter_add(obd->obd_svc_stats, PTLRPC_REQWAIT_CNTR, + timediff); + ptlrpc_lprocfs_rpc_sent(req, timediff); + } + + if (lustre_msg_get_type(req->rq_repmsg) != PTL_RPC_MSG_REPLY && + lustre_msg_get_type(req->rq_repmsg) != PTL_RPC_MSG_ERR) { + DEBUG_REQ(D_ERROR, req, "invalid packet received (type=%u)", + lustre_msg_get_type(req->rq_repmsg)); + return -EPROTO; + } + + if (lustre_msg_get_opc(req->rq_reqmsg) != OBD_PING) + CFS_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_PAUSE_REP, cfs_fail_val); + ptlrpc_at_adj_service(req, lustre_msg_get_timeout(req->rq_repmsg)); + ptlrpc_at_adj_net_latency(req, + lustre_msg_get_service_time(req->rq_repmsg)); + + rc = ptlrpc_check_status(req); + imp->imp_connect_error = rc; + + if (rc) { + /* + * Either we've been evicted, or the server has failed for + * some reason. Try to reconnect, and if that fails, punt to + * the upcall. + */ + if (ll_rpc_recoverable_error(rc)) { + if (req->rq_send_state != LUSTRE_IMP_FULL || + imp->imp_obd->obd_no_recov || imp->imp_dlm_fake) { + return rc; + } + ptlrpc_request_handle_notconn(req); + return rc; + } + } else { + /* + * Let's look if server sent slv. Do it only for RPC with + * rc == 0. + */ + ldlm_cli_update_pool(req); + } + + /* + * Store transno in reqmsg for replay. + */ + if (!(lustre_msg_get_flags(req->rq_reqmsg) & MSG_REPLAY)) { + req->rq_transno = lustre_msg_get_transno(req->rq_repmsg); + lustre_msg_set_transno(req->rq_reqmsg, req->rq_transno); + } + + if (imp->imp_replayable) { + spin_lock(&imp->imp_lock); + /* + * No point in adding already-committed requests to the replay + * list, we will just remove them immediately. b=9829 + */ + if (req->rq_transno != 0 && + (req->rq_transno > + lustre_msg_get_last_committed(req->rq_repmsg) || + req->rq_replay)) { + /** version recovery */ + ptlrpc_save_versions(req); + ptlrpc_retain_replayable_request(req, imp); + } else if (req->rq_commit_cb != NULL && + list_empty(&req->rq_replay_list)) { + /* NB: don't call rq_commit_cb if it's already on + * rq_replay_list, ptlrpc_free_committed() will call + * it later, see LU-3618 for details */ + spin_unlock(&imp->imp_lock); + req->rq_commit_cb(req); + spin_lock(&imp->imp_lock); + } + + /* + * Replay-enabled imports return commit-status information. + */ + if (lustre_msg_get_last_committed(req->rq_repmsg)) { + imp->imp_peer_committed_transno = + lustre_msg_get_last_committed(req->rq_repmsg); + } + + ptlrpc_free_committed(imp); + + if (!list_empty(&imp->imp_replay_list)) { + struct ptlrpc_request *last; + + last = list_entry(imp->imp_replay_list.prev, + struct ptlrpc_request, + rq_replay_list); + /* + * Requests with rq_replay stay on the list even if no + * commit is expected. + */ + if (last->rq_transno > imp->imp_peer_committed_transno) + ptlrpc_pinger_commit_expected(imp); + } + + spin_unlock(&imp->imp_lock); + } + + return rc; +} + +/** + * Helper function to send request \a req over the network for the first time + * Also adjusts request phase. + * Returns 0 on success or error code. + */ +static int ptlrpc_send_new_req(struct ptlrpc_request *req) +{ + struct obd_import *imp = req->rq_import; + int rc; + + LASSERT(req->rq_phase == RQ_PHASE_NEW); + if (req->rq_sent && (req->rq_sent > get_seconds()) && + (!req->rq_generation_set || + req->rq_import_generation == imp->imp_generation)) + return 0; + + ptlrpc_rqphase_move(req, RQ_PHASE_RPC); + + spin_lock(&imp->imp_lock); + + if (!req->rq_generation_set) + req->rq_import_generation = imp->imp_generation; + + if (ptlrpc_import_delay_req(imp, req, &rc)) { + spin_lock(&req->rq_lock); + req->rq_waiting = 1; + spin_unlock(&req->rq_lock); + + DEBUG_REQ(D_HA, req, "req from PID %d waiting for recovery: (%s != %s)", + lustre_msg_get_status(req->rq_reqmsg), + ptlrpc_import_state_name(req->rq_send_state), + ptlrpc_import_state_name(imp->imp_state)); + LASSERT(list_empty(&req->rq_list)); + list_add_tail(&req->rq_list, &imp->imp_delayed_list); + atomic_inc(&req->rq_import->imp_inflight); + spin_unlock(&imp->imp_lock); + return 0; + } + + if (rc != 0) { + spin_unlock(&imp->imp_lock); + req->rq_status = rc; + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + return rc; + } + + LASSERT(list_empty(&req->rq_list)); + list_add_tail(&req->rq_list, &imp->imp_sending_list); + atomic_inc(&req->rq_import->imp_inflight); + spin_unlock(&imp->imp_lock); + + lustre_msg_set_status(req->rq_reqmsg, current_pid()); + + rc = sptlrpc_req_refresh_ctx(req, -1); + if (rc) { + if (req->rq_err) { + req->rq_status = rc; + return 1; + } + spin_lock(&req->rq_lock); + req->rq_wait_ctx = 1; + spin_unlock(&req->rq_lock); + return 0; + } + + CDEBUG(D_RPCTRACE, "Sending RPC pname:cluuid:pid:xid:nid:opc %s:%s:%d:%llu:%s:%d\n", + current_comm(), + imp->imp_obd->obd_uuid.uuid, + lustre_msg_get_status(req->rq_reqmsg), req->rq_xid, + libcfs_nid2str(imp->imp_connection->c_peer.nid), + lustre_msg_get_opc(req->rq_reqmsg)); + + rc = ptl_send_rpc(req, 0); + if (rc) { + DEBUG_REQ(D_HA, req, "send failed (%d); expect timeout", rc); + spin_lock(&req->rq_lock); + req->rq_net_err = 1; + spin_unlock(&req->rq_lock); + return rc; + } + return 0; +} + +static inline int ptlrpc_set_producer(struct ptlrpc_request_set *set) +{ + int remaining, rc; + + LASSERT(set->set_producer != NULL); + + remaining = atomic_read(&set->set_remaining); + + /* populate the ->set_requests list with requests until we + * reach the maximum number of RPCs in flight for this set */ + while (atomic_read(&set->set_remaining) < set->set_max_inflight) { + rc = set->set_producer(set, set->set_producer_arg); + if (rc == -ENOENT) { + /* no more RPC to produce */ + set->set_producer = NULL; + set->set_producer_arg = NULL; + return 0; + } + } + + return (atomic_read(&set->set_remaining) - remaining); +} + +/** + * this sends any unsent RPCs in \a set and returns 1 if all are sent + * and no more replies are expected. + * (it is possible to get less replies than requests sent e.g. due to timed out + * requests or requests that we had trouble to send out) + * + * NOTE: This function contains a potential schedule point (cond_resched()). + */ +int ptlrpc_check_set(const struct lu_env *env, struct ptlrpc_request_set *set) +{ + struct list_head *tmp, *next; + struct list_head comp_reqs; + int force_timer_recalc = 0; + + if (atomic_read(&set->set_remaining) == 0) + return 1; + + INIT_LIST_HEAD(&comp_reqs); + list_for_each_safe(tmp, next, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + struct obd_import *imp = req->rq_import; + int unregistered = 0; + int rc = 0; + + /* This schedule point is mainly for the ptlrpcd caller of this + * function. Most ptlrpc sets are not long-lived and unbounded + * in length, but at the least the set used by the ptlrpcd is. + * Since the processing time is unbounded, we need to insert an + * explicit schedule point to make the thread well-behaved. + */ + cond_resched(); + + if (req->rq_phase == RQ_PHASE_NEW && + ptlrpc_send_new_req(req)) { + force_timer_recalc = 1; + } + + /* delayed send - skip */ + if (req->rq_phase == RQ_PHASE_NEW && req->rq_sent) + continue; + + /* delayed resend - skip */ + if (req->rq_phase == RQ_PHASE_RPC && req->rq_resend && + req->rq_sent > get_seconds()) + continue; + + if (!(req->rq_phase == RQ_PHASE_RPC || + req->rq_phase == RQ_PHASE_BULK || + req->rq_phase == RQ_PHASE_INTERPRET || + req->rq_phase == RQ_PHASE_UNREGISTERING || + req->rq_phase == RQ_PHASE_COMPLETE)) { + DEBUG_REQ(D_ERROR, req, "bad phase %x", req->rq_phase); + LBUG(); + } + + if (req->rq_phase == RQ_PHASE_UNREGISTERING) { + LASSERT(req->rq_next_phase != req->rq_phase); + LASSERT(req->rq_next_phase != RQ_PHASE_UNDEFINED); + + /* + * Skip processing until reply is unlinked. We + * can't return to pool before that and we can't + * call interpret before that. We need to make + * sure that all rdma transfers finished and will + * not corrupt any data. + */ + if (ptlrpc_client_recv_or_unlink(req) || + ptlrpc_client_bulk_active(req)) + continue; + + /* + * Turn fail_loc off to prevent it from looping + * forever. + */ + if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_REPL_UNLINK)) { + OBD_FAIL_CHECK_ORSET(OBD_FAIL_PTLRPC_LONG_REPL_UNLINK, + OBD_FAIL_ONCE); + } + if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_BULK_UNLINK)) { + OBD_FAIL_CHECK_ORSET(OBD_FAIL_PTLRPC_LONG_BULK_UNLINK, + OBD_FAIL_ONCE); + } + + /* + * Move to next phase if reply was successfully + * unlinked. + */ + ptlrpc_rqphase_move(req, req->rq_next_phase); + } + + if (req->rq_phase == RQ_PHASE_COMPLETE) { + list_move_tail(&req->rq_set_chain, &comp_reqs); + continue; + } + + if (req->rq_phase == RQ_PHASE_INTERPRET) + goto interpret; + + /* + * Note that this also will start async reply unlink. + */ + if (req->rq_net_err && !req->rq_timedout) { + ptlrpc_expire_one_request(req, 1); + + /* + * Check if we still need to wait for unlink. + */ + if (ptlrpc_client_recv_or_unlink(req) || + ptlrpc_client_bulk_active(req)) + continue; + /* If there is no need to resend, fail it now. */ + if (req->rq_no_resend) { + if (req->rq_status == 0) + req->rq_status = -EIO; + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + goto interpret; + } else { + continue; + } + } + + if (req->rq_err) { + spin_lock(&req->rq_lock); + req->rq_replied = 0; + spin_unlock(&req->rq_lock); + if (req->rq_status == 0) + req->rq_status = -EIO; + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + goto interpret; + } + + /* ptlrpc_set_wait->l_wait_event sets lwi_allow_intr + * so it sets rq_intr regardless of individual rpc + * timeouts. The synchronous IO waiting path sets + * rq_intr irrespective of whether ptlrpcd + * has seen a timeout. Our policy is to only interpret + * interrupted rpcs after they have timed out, so we + * need to enforce that here. + */ + + if (req->rq_intr && (req->rq_timedout || req->rq_waiting || + req->rq_wait_ctx)) { + req->rq_status = -EINTR; + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + goto interpret; + } + + if (req->rq_phase == RQ_PHASE_RPC) { + if (req->rq_timedout || req->rq_resend || + req->rq_waiting || req->rq_wait_ctx) { + int status; + + if (!ptlrpc_unregister_reply(req, 1)) + continue; + + spin_lock(&imp->imp_lock); + if (ptlrpc_import_delay_req(imp, req, + &status)) { + /* put on delay list - only if we wait + * recovery finished - before send */ + list_del_init(&req->rq_list); + list_add_tail(&req->rq_list, + &imp-> + imp_delayed_list); + spin_unlock(&imp->imp_lock); + continue; + } + + if (status != 0) { + req->rq_status = status; + ptlrpc_rqphase_move(req, + RQ_PHASE_INTERPRET); + spin_unlock(&imp->imp_lock); + goto interpret; + } + if (ptlrpc_no_resend(req) && + !req->rq_wait_ctx) { + req->rq_status = -ENOTCONN; + ptlrpc_rqphase_move(req, + RQ_PHASE_INTERPRET); + spin_unlock(&imp->imp_lock); + goto interpret; + } + + list_del_init(&req->rq_list); + list_add_tail(&req->rq_list, + &imp->imp_sending_list); + + spin_unlock(&imp->imp_lock); + + spin_lock(&req->rq_lock); + req->rq_waiting = 0; + spin_unlock(&req->rq_lock); + + if (req->rq_timedout || req->rq_resend) { + /* This is re-sending anyways, + * let's mark req as resend. */ + spin_lock(&req->rq_lock); + req->rq_resend = 1; + spin_unlock(&req->rq_lock); + if (req->rq_bulk) { + __u64 old_xid; + + if (!ptlrpc_unregister_bulk(req, 1)) + continue; + + /* ensure previous bulk fails */ + old_xid = req->rq_xid; + req->rq_xid = ptlrpc_next_xid(); + CDEBUG(D_HA, "resend bulk old x%llu new x%llu\n", + old_xid, req->rq_xid); + } + } + /* + * rq_wait_ctx is only touched by ptlrpcd, + * so no lock is needed here. + */ + status = sptlrpc_req_refresh_ctx(req, -1); + if (status) { + if (req->rq_err) { + req->rq_status = status; + spin_lock(&req->rq_lock); + req->rq_wait_ctx = 0; + spin_unlock(&req->rq_lock); + force_timer_recalc = 1; + } else { + spin_lock(&req->rq_lock); + req->rq_wait_ctx = 1; + spin_unlock(&req->rq_lock); + } + + continue; + } else { + spin_lock(&req->rq_lock); + req->rq_wait_ctx = 0; + spin_unlock(&req->rq_lock); + } + + rc = ptl_send_rpc(req, 0); + if (rc) { + DEBUG_REQ(D_HA, req, + "send failed: rc = %d", rc); + force_timer_recalc = 1; + spin_lock(&req->rq_lock); + req->rq_net_err = 1; + spin_unlock(&req->rq_lock); + continue; + } + /* need to reset the timeout */ + force_timer_recalc = 1; + } + + spin_lock(&req->rq_lock); + + if (ptlrpc_client_early(req)) { + ptlrpc_at_recv_early_reply(req); + spin_unlock(&req->rq_lock); + continue; + } + + /* Still waiting for a reply? */ + if (ptlrpc_client_recv(req)) { + spin_unlock(&req->rq_lock); + continue; + } + + /* Did we actually receive a reply? */ + if (!ptlrpc_client_replied(req)) { + spin_unlock(&req->rq_lock); + continue; + } + + spin_unlock(&req->rq_lock); + + /* unlink from net because we are going to + * swab in-place of reply buffer */ + unregistered = ptlrpc_unregister_reply(req, 1); + if (!unregistered) + continue; + + req->rq_status = after_reply(req); + if (req->rq_resend) + continue; + + /* If there is no bulk associated with this request, + * then we're done and should let the interpreter + * process the reply. Similarly if the RPC returned + * an error, and therefore the bulk will never arrive. + */ + if (req->rq_bulk == NULL || req->rq_status < 0) { + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + goto interpret; + } + + ptlrpc_rqphase_move(req, RQ_PHASE_BULK); + } + + LASSERT(req->rq_phase == RQ_PHASE_BULK); + if (ptlrpc_client_bulk_active(req)) + continue; + + if (req->rq_bulk->bd_failure) { + /* The RPC reply arrived OK, but the bulk screwed + * up! Dead weird since the server told us the RPC + * was good after getting the REPLY for her GET or + * the ACK for her PUT. */ + DEBUG_REQ(D_ERROR, req, "bulk transfer failed"); + req->rq_status = -EIO; + } + + ptlrpc_rqphase_move(req, RQ_PHASE_INTERPRET); + +interpret: + LASSERT(req->rq_phase == RQ_PHASE_INTERPRET); + + /* This moves to "unregistering" phase we need to wait for + * reply unlink. */ + if (!unregistered && !ptlrpc_unregister_reply(req, 1)) { + /* start async bulk unlink too */ + ptlrpc_unregister_bulk(req, 1); + continue; + } + + if (!ptlrpc_unregister_bulk(req, 1)) + continue; + + /* When calling interpret receiving already should be + * finished. */ + LASSERT(!req->rq_receiving_reply); + + ptlrpc_req_interpret(env, req, req->rq_status); + + if (ptlrpcd_check_work(req)) { + atomic_dec(&set->set_remaining); + continue; + } + ptlrpc_rqphase_move(req, RQ_PHASE_COMPLETE); + + CDEBUG(req->rq_reqmsg != NULL ? D_RPCTRACE : 0, + "Completed RPC pname:cluuid:pid:xid:nid:opc %s:%s:%d:%llu:%s:%d\n", + current_comm(), imp->imp_obd->obd_uuid.uuid, + lustre_msg_get_status(req->rq_reqmsg), req->rq_xid, + libcfs_nid2str(imp->imp_connection->c_peer.nid), + lustre_msg_get_opc(req->rq_reqmsg)); + + spin_lock(&imp->imp_lock); + /* Request already may be not on sending or delaying list. This + * may happen in the case of marking it erroneous for the case + * ptlrpc_import_delay_req(req, status) find it impossible to + * allow sending this rpc and returns *status != 0. */ + if (!list_empty(&req->rq_list)) { + list_del_init(&req->rq_list); + atomic_dec(&imp->imp_inflight); + } + spin_unlock(&imp->imp_lock); + + atomic_dec(&set->set_remaining); + wake_up_all(&imp->imp_recovery_waitq); + + if (set->set_producer) { + /* produce a new request if possible */ + if (ptlrpc_set_producer(set) > 0) + force_timer_recalc = 1; + + /* free the request that has just been completed + * in order not to pollute set->set_requests */ + list_del_init(&req->rq_set_chain); + spin_lock(&req->rq_lock); + req->rq_set = NULL; + req->rq_invalid_rqset = 0; + spin_unlock(&req->rq_lock); + + /* record rq_status to compute the final status later */ + if (req->rq_status != 0) + set->set_rc = req->rq_status; + ptlrpc_req_finished(req); + } else { + list_move_tail(&req->rq_set_chain, &comp_reqs); + } + } + + /* move completed request at the head of list so it's easier for + * caller to find them */ + list_splice(&comp_reqs, &set->set_requests); + + /* If we hit an error, we want to recover promptly. */ + return atomic_read(&set->set_remaining) == 0 || force_timer_recalc; +} +EXPORT_SYMBOL(ptlrpc_check_set); + +/** + * Time out request \a req. is \a async_unlink is set, that means do not wait + * until LNet actually confirms network buffer unlinking. + * Return 1 if we should give up further retrying attempts or 0 otherwise. + */ +int ptlrpc_expire_one_request(struct ptlrpc_request *req, int async_unlink) +{ + struct obd_import *imp = req->rq_import; + int rc = 0; + + spin_lock(&req->rq_lock); + req->rq_timedout = 1; + spin_unlock(&req->rq_lock); + + DEBUG_REQ(D_WARNING, req, "Request sent has %s: [sent "CFS_DURATION_T + "/real "CFS_DURATION_T"]", + req->rq_net_err ? "failed due to network error" : + ((req->rq_real_sent == 0 || + time_before((unsigned long)req->rq_real_sent, (unsigned long)req->rq_sent) || + cfs_time_aftereq(req->rq_real_sent, req->rq_deadline)) ? + "timed out for sent delay" : "timed out for slow reply"), + req->rq_sent, req->rq_real_sent); + + if (imp != NULL && obd_debug_peer_on_timeout) + LNetCtl(IOC_LIBCFS_DEBUG_PEER, &imp->imp_connection->c_peer); + + ptlrpc_unregister_reply(req, async_unlink); + ptlrpc_unregister_bulk(req, async_unlink); + + if (obd_dump_on_timeout) + libcfs_debug_dumplog(); + + if (imp == NULL) { + DEBUG_REQ(D_HA, req, "NULL import: already cleaned up?"); + return 1; + } + + atomic_inc(&imp->imp_timeouts); + + /* The DLM server doesn't want recovery run on its imports. */ + if (imp->imp_dlm_fake) + return 1; + + /* If this request is for recovery or other primordial tasks, + * then error it out here. */ + if (req->rq_ctx_init || req->rq_ctx_fini || + req->rq_send_state != LUSTRE_IMP_FULL || + imp->imp_obd->obd_no_recov) { + DEBUG_REQ(D_RPCTRACE, req, "err -110, sent_state=%s (now=%s)", + ptlrpc_import_state_name(req->rq_send_state), + ptlrpc_import_state_name(imp->imp_state)); + spin_lock(&req->rq_lock); + req->rq_status = -ETIMEDOUT; + req->rq_err = 1; + spin_unlock(&req->rq_lock); + return 1; + } + + /* if a request can't be resent we can't wait for an answer after + the timeout */ + if (ptlrpc_no_resend(req)) { + DEBUG_REQ(D_RPCTRACE, req, "TIMEOUT-NORESEND:"); + rc = 1; + } + + ptlrpc_fail_import(imp, lustre_msg_get_conn_cnt(req->rq_reqmsg)); + + return rc; +} + +/** + * Time out all uncompleted requests in request set pointed by \a data + * Callback used when waiting on sets with l_wait_event. + * Always returns 1. + */ +int ptlrpc_expired_set(void *data) +{ + struct ptlrpc_request_set *set = data; + struct list_head *tmp; + time_t now = get_seconds(); + + LASSERT(set != NULL); + + /* + * A timeout expired. See which reqs it applies to... + */ + list_for_each(tmp, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + + /* don't expire request waiting for context */ + if (req->rq_wait_ctx) + continue; + + /* Request in-flight? */ + if (!((req->rq_phase == RQ_PHASE_RPC && + !req->rq_waiting && !req->rq_resend) || + (req->rq_phase == RQ_PHASE_BULK))) + continue; + + if (req->rq_timedout || /* already dealt with */ + req->rq_deadline > now) /* not expired */ + continue; + + /* Deal with this guy. Do it asynchronously to not block + * ptlrpcd thread. */ + ptlrpc_expire_one_request(req, 1); + } + + /* + * When waiting for a whole set, we always break out of the + * sleep so we can recalculate the timeout, or enable interrupts + * if everyone's timed out. + */ + return 1; +} +EXPORT_SYMBOL(ptlrpc_expired_set); + +/** + * Sets rq_intr flag in \a req under spinlock. + */ +void ptlrpc_mark_interrupted(struct ptlrpc_request *req) +{ + spin_lock(&req->rq_lock); + req->rq_intr = 1; + spin_unlock(&req->rq_lock); +} +EXPORT_SYMBOL(ptlrpc_mark_interrupted); + +/** + * Interrupts (sets interrupted flag) all uncompleted requests in + * a set \a data. Callback for l_wait_event for interruptible waits. + */ +void ptlrpc_interrupted_set(void *data) +{ + struct ptlrpc_request_set *set = data; + struct list_head *tmp; + + LASSERT(set != NULL); + CDEBUG(D_RPCTRACE, "INTERRUPTED SET %p\n", set); + + list_for_each(tmp, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + + if (req->rq_phase != RQ_PHASE_RPC && + req->rq_phase != RQ_PHASE_UNREGISTERING) + continue; + + ptlrpc_mark_interrupted(req); + } +} +EXPORT_SYMBOL(ptlrpc_interrupted_set); + +/** + * Get the smallest timeout in the set; this does NOT set a timeout. + */ +int ptlrpc_set_next_timeout(struct ptlrpc_request_set *set) +{ + struct list_head *tmp; + time_t now = get_seconds(); + int timeout = 0; + struct ptlrpc_request *req; + int deadline; + + list_for_each(tmp, &set->set_requests) { + req = list_entry(tmp, struct ptlrpc_request, rq_set_chain); + + /* + * Request in-flight? + */ + if (!(((req->rq_phase == RQ_PHASE_RPC) && !req->rq_waiting) || + (req->rq_phase == RQ_PHASE_BULK) || + (req->rq_phase == RQ_PHASE_NEW))) + continue; + + /* + * Already timed out. + */ + if (req->rq_timedout) + continue; + + /* + * Waiting for ctx. + */ + if (req->rq_wait_ctx) + continue; + + if (req->rq_phase == RQ_PHASE_NEW) + deadline = req->rq_sent; + else if (req->rq_phase == RQ_PHASE_RPC && req->rq_resend) + deadline = req->rq_sent; + else + deadline = req->rq_sent + req->rq_timeout; + + if (deadline <= now) /* actually expired already */ + timeout = 1; /* ASAP */ + else if (timeout == 0 || timeout > deadline - now) + timeout = deadline - now; + } + return timeout; +} +EXPORT_SYMBOL(ptlrpc_set_next_timeout); + +/** + * Send all unset request from the set and then wait until all + * requests in the set complete (either get a reply, timeout, get an + * error or otherwise be interrupted). + * Returns 0 on success or error code otherwise. + */ +int ptlrpc_set_wait(struct ptlrpc_request_set *set) +{ + struct list_head *tmp; + struct ptlrpc_request *req; + struct l_wait_info lwi; + int rc, timeout; + + if (set->set_producer) + (void)ptlrpc_set_producer(set); + else + list_for_each(tmp, &set->set_requests) { + req = list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + if (req->rq_phase == RQ_PHASE_NEW) + (void)ptlrpc_send_new_req(req); + } + + if (list_empty(&set->set_requests)) + return 0; + + do { + timeout = ptlrpc_set_next_timeout(set); + + /* wait until all complete, interrupted, or an in-flight + * req times out */ + CDEBUG(D_RPCTRACE, "set %p going to sleep for %d seconds\n", + set, timeout); + + if (timeout == 0 && !cfs_signal_pending()) + /* + * No requests are in-flight (ether timed out + * or delayed), so we can allow interrupts. + * We still want to block for a limited time, + * so we allow interrupts during the timeout. + */ + lwi = LWI_TIMEOUT_INTR_ALL(cfs_time_seconds(1), + ptlrpc_expired_set, + ptlrpc_interrupted_set, set); + else + /* + * At least one request is in flight, so no + * interrupts are allowed. Wait until all + * complete, or an in-flight req times out. + */ + lwi = LWI_TIMEOUT(cfs_time_seconds(timeout ? timeout : 1), + ptlrpc_expired_set, set); + + rc = l_wait_event(set->set_waitq, ptlrpc_check_set(NULL, set), &lwi); + + /* LU-769 - if we ignored the signal because it was already + * pending when we started, we need to handle it now or we risk + * it being ignored forever */ + if (rc == -ETIMEDOUT && !lwi.lwi_allow_intr && + cfs_signal_pending()) { + sigset_t blocked_sigs = + cfs_block_sigsinv(LUSTRE_FATAL_SIGS); + + /* In fact we only interrupt for the "fatal" signals + * like SIGINT or SIGKILL. We still ignore less + * important signals since ptlrpc set is not easily + * reentrant from userspace again */ + if (cfs_signal_pending()) + ptlrpc_interrupted_set(set); + cfs_restore_sigs(blocked_sigs); + } + + LASSERT(rc == 0 || rc == -EINTR || rc == -ETIMEDOUT); + + /* -EINTR => all requests have been flagged rq_intr so next + * check completes. + * -ETIMEDOUT => someone timed out. When all reqs have + * timed out, signals are enabled allowing completion with + * EINTR. + * I don't really care if we go once more round the loop in + * the error cases -eeb. */ + if (rc == 0 && atomic_read(&set->set_remaining) == 0) { + list_for_each(tmp, &set->set_requests) { + req = list_entry(tmp, struct ptlrpc_request, + rq_set_chain); + spin_lock(&req->rq_lock); + req->rq_invalid_rqset = 1; + spin_unlock(&req->rq_lock); + } + } + } while (rc != 0 || atomic_read(&set->set_remaining) != 0); + + LASSERT(atomic_read(&set->set_remaining) == 0); + + rc = set->set_rc; /* rq_status of already freed requests if any */ + list_for_each(tmp, &set->set_requests) { + req = list_entry(tmp, struct ptlrpc_request, rq_set_chain); + + LASSERT(req->rq_phase == RQ_PHASE_COMPLETE); + if (req->rq_status != 0) + rc = req->rq_status; + } + + if (set->set_interpret != NULL) { + int (*interpreter)(struct ptlrpc_request_set *set, void *, int) = + set->set_interpret; + rc = interpreter(set, set->set_arg, rc); + } else { + struct ptlrpc_set_cbdata *cbdata, *n; + int err; + + list_for_each_entry_safe(cbdata, n, + &set->set_cblist, psc_item) { + list_del_init(&cbdata->psc_item); + err = cbdata->psc_interpret(set, cbdata->psc_data, rc); + if (err && !rc) + rc = err; + OBD_FREE_PTR(cbdata); + } + } + + return rc; +} +EXPORT_SYMBOL(ptlrpc_set_wait); + +/** + * Helper function for request freeing. + * Called when request count reached zero and request needs to be freed. + * Removes request from all sorts of sending/replay lists it might be on, + * frees network buffers if any are present. + * If \a locked is set, that means caller is already holding import imp_lock + * and so we no longer need to reobtain it (for certain lists manipulations) + */ +static void __ptlrpc_free_req(struct ptlrpc_request *request, int locked) +{ + if (request == NULL) + return; + LASSERTF(!request->rq_receiving_reply, "req %p\n", request); + LASSERTF(request->rq_rqbd == NULL, "req %p\n", request);/* client-side */ + LASSERTF(list_empty(&request->rq_list), "req %p\n", request); + LASSERTF(list_empty(&request->rq_set_chain), "req %p\n", request); + LASSERTF(list_empty(&request->rq_exp_list), "req %p\n", request); + LASSERTF(!request->rq_replay, "req %p\n", request); + + req_capsule_fini(&request->rq_pill); + + /* We must take it off the imp_replay_list first. Otherwise, we'll set + * request->rq_reqmsg to NULL while osc_close is dereferencing it. */ + if (request->rq_import != NULL) { + if (!locked) + spin_lock(&request->rq_import->imp_lock); + list_del_init(&request->rq_replay_list); + if (!locked) + spin_unlock(&request->rq_import->imp_lock); + } + LASSERTF(list_empty(&request->rq_replay_list), "req %p\n", request); + + if (atomic_read(&request->rq_refcount) != 0) { + DEBUG_REQ(D_ERROR, request, + "freeing request with nonzero refcount"); + LBUG(); + } + + if (request->rq_repbuf != NULL) + sptlrpc_cli_free_repbuf(request); + if (request->rq_export != NULL) { + class_export_put(request->rq_export); + request->rq_export = NULL; + } + if (request->rq_import != NULL) { + class_import_put(request->rq_import); + request->rq_import = NULL; + } + if (request->rq_bulk != NULL) + ptlrpc_free_bulk_pin(request->rq_bulk); + + if (request->rq_reqbuf != NULL || request->rq_clrbuf != NULL) + sptlrpc_cli_free_reqbuf(request); + + if (request->rq_cli_ctx) + sptlrpc_req_put_ctx(request, !locked); + + if (request->rq_pool) + __ptlrpc_free_req_to_pool(request); + else + ptlrpc_request_cache_free(request); +} + +static int __ptlrpc_req_finished(struct ptlrpc_request *request, int locked); +/** + * Drop one request reference. Must be called with import imp_lock held. + * When reference count drops to zero, request is freed. + */ +void ptlrpc_req_finished_with_imp_lock(struct ptlrpc_request *request) +{ + assert_spin_locked(&request->rq_import->imp_lock); + (void)__ptlrpc_req_finished(request, 1); +} +EXPORT_SYMBOL(ptlrpc_req_finished_with_imp_lock); + +/** + * Helper function + * Drops one reference count for request \a request. + * \a locked set indicates that caller holds import imp_lock. + * Frees the request when reference count reaches zero. + */ +static int __ptlrpc_req_finished(struct ptlrpc_request *request, int locked) +{ + if (request == NULL) + return 1; + + if (request == LP_POISON || + request->rq_reqmsg == LP_POISON) { + CERROR("dereferencing freed request (bug 575)\n"); + LBUG(); + return 1; + } + + DEBUG_REQ(D_INFO, request, "refcount now %u", + atomic_read(&request->rq_refcount) - 1); + + if (atomic_dec_and_test(&request->rq_refcount)) { + __ptlrpc_free_req(request, locked); + return 1; + } + + return 0; +} + +/** + * Drops one reference count for a request. + */ +void ptlrpc_req_finished(struct ptlrpc_request *request) +{ + __ptlrpc_req_finished(request, 0); +} +EXPORT_SYMBOL(ptlrpc_req_finished); + +/** + * Returns xid of a \a request + */ +__u64 ptlrpc_req_xid(struct ptlrpc_request *request) +{ + return request->rq_xid; +} +EXPORT_SYMBOL(ptlrpc_req_xid); + +/** + * Disengage the client's reply buffer from the network + * NB does _NOT_ unregister any client-side bulk. + * IDEMPOTENT, but _not_ safe against concurrent callers. + * The request owner (i.e. the thread doing the I/O) must call... + * Returns 0 on success or 1 if unregistering cannot be made. + */ +int ptlrpc_unregister_reply(struct ptlrpc_request *request, int async) +{ + int rc; + wait_queue_head_t *wq; + struct l_wait_info lwi; + + /* + * Might sleep. + */ + LASSERT(!in_interrupt()); + + /* + * Let's setup deadline for reply unlink. + */ + if (OBD_FAIL_CHECK(OBD_FAIL_PTLRPC_LONG_REPL_UNLINK) && + async && request->rq_reply_deadline == 0) + request->rq_reply_deadline = get_seconds()+LONG_UNLINK; + + /* + * Nothing left to do. + */ + if (!ptlrpc_client_recv_or_unlink(request)) + return 1; + + LNetMDUnlink(request->rq_reply_md_h); + + /* + * Let's check it once again. + */ + if (!ptlrpc_client_recv_or_unlink(request)) + return 1; + + /* + * Move to "Unregistering" phase as reply was not unlinked yet. + */ + ptlrpc_rqphase_move(request, RQ_PHASE_UNREGISTERING); + + /* + * Do not wait for unlink to finish. + */ + if (async) + return 0; + + /* + * We have to l_wait_event() whatever the result, to give liblustre + * a chance to run reply_in_callback(), and to make sure we've + * unlinked before returning a req to the pool. + */ + if (request->rq_set != NULL) + wq = &request->rq_set->set_waitq; + else + wq = &request->rq_reply_waitq; + + for (;;) { + /* Network access will complete in finite time but the HUGE + * timeout lets us CWARN for visibility of sluggish NALs */ + lwi = LWI_TIMEOUT_INTERVAL(cfs_time_seconds(LONG_UNLINK), + cfs_time_seconds(1), NULL, NULL); + rc = l_wait_event(*wq, !ptlrpc_client_recv_or_unlink(request), + &lwi); + if (rc == 0) { + ptlrpc_rqphase_move(request, request->rq_next_phase); + return 1; + } + + LASSERT(rc == -ETIMEDOUT); + DEBUG_REQ(D_WARNING, request, + "Unexpectedly long timeout rvcng=%d unlnk=%d/%d", + request->rq_receiving_reply, + request->rq_req_unlink, request->rq_reply_unlink); + } + return 0; +} +EXPORT_SYMBOL(ptlrpc_unregister_reply); + +static void ptlrpc_free_request(struct ptlrpc_request *req) +{ + spin_lock(&req->rq_lock); + req->rq_replay = 0; + spin_unlock(&req->rq_lock); + + if (req->rq_commit_cb != NULL) + req->rq_commit_cb(req); + list_del_init(&req->rq_replay_list); + + __ptlrpc_req_finished(req, 1); +} + +/** + * the request is committed and dropped from the replay list of its import + */ +void ptlrpc_request_committed(struct ptlrpc_request *req, int force) +{ + struct obd_import *imp = req->rq_import; + + spin_lock(&imp->imp_lock); + if (list_empty(&req->rq_replay_list)) { + spin_unlock(&imp->imp_lock); + return; + } + + if (force || req->rq_transno <= imp->imp_peer_committed_transno) + ptlrpc_free_request(req); + + spin_unlock(&imp->imp_lock); +} +EXPORT_SYMBOL(ptlrpc_request_committed); + +/** + * Iterates through replay_list on import and prunes + * all requests have transno smaller than last_committed for the + * import and don't have rq_replay set. + * Since requests are sorted in transno order, stops when meeting first + * transno bigger than last_committed. + * caller must hold imp->imp_lock + */ +void ptlrpc_free_committed(struct obd_import *imp) +{ + struct ptlrpc_request *req, *saved; + struct ptlrpc_request *last_req = NULL; /* temporary fire escape */ + bool skip_committed_list = true; + + LASSERT(imp != NULL); + assert_spin_locked(&imp->imp_lock); + + if (imp->imp_peer_committed_transno == imp->imp_last_transno_checked && + imp->imp_generation == imp->imp_last_generation_checked) { + CDEBUG(D_INFO, "%s: skip recheck: last_committed %llu\n", + imp->imp_obd->obd_name, imp->imp_peer_committed_transno); + return; + } + CDEBUG(D_RPCTRACE, "%s: committing for last_committed %llu gen %d\n", + imp->imp_obd->obd_name, imp->imp_peer_committed_transno, + imp->imp_generation); + + if (imp->imp_generation != imp->imp_last_generation_checked) + skip_committed_list = false; + + imp->imp_last_transno_checked = imp->imp_peer_committed_transno; + imp->imp_last_generation_checked = imp->imp_generation; + + list_for_each_entry_safe(req, saved, &imp->imp_replay_list, + rq_replay_list) { + /* XXX ok to remove when 1357 resolved - rread 05/29/03 */ + LASSERT(req != last_req); + last_req = req; + + if (req->rq_transno == 0) { + DEBUG_REQ(D_EMERG, req, "zero transno during replay"); + LBUG(); + } + if (req->rq_import_generation < imp->imp_generation) { + DEBUG_REQ(D_RPCTRACE, req, "free request with old gen"); + goto free_req; + } + + /* not yet committed */ + if (req->rq_transno > imp->imp_peer_committed_transno) { + DEBUG_REQ(D_RPCTRACE, req, "stopping search"); + break; + } + + if (req->rq_replay) { + DEBUG_REQ(D_RPCTRACE, req, "keeping (FL_REPLAY)"); + list_move_tail(&req->rq_replay_list, + &imp->imp_committed_list); + continue; + } + + DEBUG_REQ(D_INFO, req, "commit (last_committed %llu)", + imp->imp_peer_committed_transno); +free_req: + ptlrpc_free_request(req); + } + if (skip_committed_list) + return; + + list_for_each_entry_safe(req, saved, &imp->imp_committed_list, + rq_replay_list) { + LASSERT(req->rq_transno != 0); + if (req->rq_import_generation < imp->imp_generation) { + DEBUG_REQ(D_RPCTRACE, req, "free stale open request"); + ptlrpc_free_request(req); + } + } +} + +void ptlrpc_cleanup_client(struct obd_import *imp) +{ +} +EXPORT_SYMBOL(ptlrpc_cleanup_client); + +/** + * Schedule previously sent request for resend. + * For bulk requests we assign new xid (to avoid problems with + * lost replies and therefore several transfers landing into same buffer + * from different sending attempts). + */ +void ptlrpc_resend_req(struct ptlrpc_request *req) +{ + DEBUG_REQ(D_HA, req, "going to resend"); + spin_lock(&req->rq_lock); + + /* Request got reply but linked to the import list still. + Let ptlrpc_check_set() to process it. */ + if (ptlrpc_client_replied(req)) { + spin_unlock(&req->rq_lock); + DEBUG_REQ(D_HA, req, "it has reply, so skip it"); + return; + } + + lustre_msg_set_handle(req->rq_reqmsg, &(struct lustre_handle){ 0 }); + req->rq_status = -EAGAIN; + + req->rq_resend = 1; + req->rq_net_err = 0; + req->rq_timedout = 0; + if (req->rq_bulk) { + __u64 old_xid = req->rq_xid; + + /* ensure previous bulk fails */ + req->rq_xid = ptlrpc_next_xid(); + CDEBUG(D_HA, "resend bulk old x%llu new x%llu\n", + old_xid, req->rq_xid); + } + ptlrpc_client_wake_req(req); + spin_unlock(&req->rq_lock); +} +EXPORT_SYMBOL(ptlrpc_resend_req); + +/* XXX: this function and rq_status are currently unused */ +void ptlrpc_restart_req(struct ptlrpc_request *req) +{ + DEBUG_REQ(D_HA, req, "restarting (possibly-)completed request"); + req->rq_status = -ERESTARTSYS; + + spin_lock(&req->rq_lock); + req->rq_restart = 1; + req->rq_timedout = 0; + ptlrpc_client_wake_req(req); + spin_unlock(&req->rq_lock); +} +EXPORT_SYMBOL(ptlrpc_restart_req); + +/** + * Grab additional reference on a request \a req + */ +struct ptlrpc_request *ptlrpc_request_addref(struct ptlrpc_request *req) +{ + atomic_inc(&req->rq_refcount); + return req; +} +EXPORT_SYMBOL(ptlrpc_request_addref); + +/** + * Add a request to import replay_list. + * Must be called under imp_lock + */ +void ptlrpc_retain_replayable_request(struct ptlrpc_request *req, + struct obd_import *imp) +{ + struct list_head *tmp; + + assert_spin_locked(&imp->imp_lock); + + if (req->rq_transno == 0) { + DEBUG_REQ(D_EMERG, req, "saving request with zero transno"); + LBUG(); + } + + /* clear this for new requests that were resent as well + as resent replayed requests. */ + lustre_msg_clear_flags(req->rq_reqmsg, MSG_RESENT); + + /* don't re-add requests that have been replayed */ + if (!list_empty(&req->rq_replay_list)) + return; + + lustre_msg_add_flags(req->rq_reqmsg, MSG_REPLAY); + + LASSERT(imp->imp_replayable); + /* Balanced in ptlrpc_free_committed, usually. */ + ptlrpc_request_addref(req); + list_for_each_prev(tmp, &imp->imp_replay_list) { + struct ptlrpc_request *iter = + list_entry(tmp, struct ptlrpc_request, + rq_replay_list); + + /* We may have duplicate transnos if we create and then + * open a file, or for closes retained if to match creating + * opens, so use req->rq_xid as a secondary key. + * (See bugs 684, 685, and 428.) + * XXX no longer needed, but all opens need transnos! + */ + if (iter->rq_transno > req->rq_transno) + continue; + + if (iter->rq_transno == req->rq_transno) { + LASSERT(iter->rq_xid != req->rq_xid); + if (iter->rq_xid > req->rq_xid) + continue; + } + + list_add(&req->rq_replay_list, &iter->rq_replay_list); + return; + } + + list_add(&req->rq_replay_list, &imp->imp_replay_list); +} +EXPORT_SYMBOL(ptlrpc_retain_replayable_request); + +/** + * Send request and wait until it completes. + * Returns request processing status. + */ +int ptlrpc_queue_wait(struct ptlrpc_request *req) +{ + struct ptlrpc_request_set *set; + int rc; + + LASSERT(req->rq_set == NULL); + LASSERT(!req->rq_receiving_reply); + + set = ptlrpc_prep_set(); + if (set == NULL) { + CERROR("Unable to allocate ptlrpc set."); + return -ENOMEM; + } + + /* for distributed debugging */ + lustre_msg_set_status(req->rq_reqmsg, current_pid()); + + /* add a ref for the set (see comment in ptlrpc_set_add_req) */ + ptlrpc_request_addref(req); + ptlrpc_set_add_req(set, req); + rc = ptlrpc_set_wait(set); + ptlrpc_set_destroy(set); + + return rc; +} +EXPORT_SYMBOL(ptlrpc_queue_wait); + +struct ptlrpc_replay_async_args { + int praa_old_state; + int praa_old_status; +}; + +/** + * Callback used for replayed requests reply processing. + * In case of successful reply calls registered request replay callback. + * In case of error restart replay process. + */ +static int ptlrpc_replay_interpret(const struct lu_env *env, + struct ptlrpc_request *req, + void *data, int rc) +{ + struct ptlrpc_replay_async_args *aa = data; + struct obd_import *imp = req->rq_import; + + atomic_dec(&imp->imp_replay_inflight); + + if (!ptlrpc_client_replied(req)) { + CERROR("request replay timed out, restarting recovery\n"); + rc = -ETIMEDOUT; + goto out; + } + + if (lustre_msg_get_type(req->rq_repmsg) == PTL_RPC_MSG_ERR && + (lustre_msg_get_status(req->rq_repmsg) == -ENOTCONN || + lustre_msg_get_status(req->rq_repmsg) == -ENODEV)) { + rc = lustre_msg_get_status(req->rq_repmsg); + goto out; + } + + /** VBR: check version failure */ + if (lustre_msg_get_status(req->rq_repmsg) == -EOVERFLOW) { + /** replay was failed due to version mismatch */ + DEBUG_REQ(D_WARNING, req, "Version mismatch during replay\n"); + spin_lock(&imp->imp_lock); + imp->imp_vbr_failed = 1; + imp->imp_no_lock_replay = 1; + spin_unlock(&imp->imp_lock); + lustre_msg_set_status(req->rq_repmsg, aa->praa_old_status); + } else { + /** The transno had better not change over replay. */ + LASSERTF(lustre_msg_get_transno(req->rq_reqmsg) == + lustre_msg_get_transno(req->rq_repmsg) || + lustre_msg_get_transno(req->rq_repmsg) == 0, + "%#llx/%#llx\n", + lustre_msg_get_transno(req->rq_reqmsg), + lustre_msg_get_transno(req->rq_repmsg)); + } + + spin_lock(&imp->imp_lock); + /** if replays by version then gap occur on server, no trust to locks */ + if (lustre_msg_get_flags(req->rq_repmsg) & MSG_VERSION_REPLAY) + imp->imp_no_lock_replay = 1; + imp->imp_last_replay_transno = lustre_msg_get_transno(req->rq_reqmsg); + spin_unlock(&imp->imp_lock); + LASSERT(imp->imp_last_replay_transno); + + /* transaction number shouldn't be bigger than the latest replayed */ + if (req->rq_transno > lustre_msg_get_transno(req->rq_reqmsg)) { + DEBUG_REQ(D_ERROR, req, + "Reported transno %llu is bigger than the replayed one: %llu", + req->rq_transno, + lustre_msg_get_transno(req->rq_reqmsg)); + rc = -EINVAL; + goto out; + } + + DEBUG_REQ(D_HA, req, "got rep"); + + /* let the callback do fixups, possibly including in the request */ + if (req->rq_replay_cb) + req->rq_replay_cb(req); + + if (ptlrpc_client_replied(req) && + lustre_msg_get_status(req->rq_repmsg) != aa->praa_old_status) { + DEBUG_REQ(D_ERROR, req, "status %d, old was %d", + lustre_msg_get_status(req->rq_repmsg), + aa->praa_old_status); + } else { + /* Put it back for re-replay. */ + lustre_msg_set_status(req->rq_repmsg, aa->praa_old_status); + } + + /* + * Errors while replay can set transno to 0, but + * imp_last_replay_transno shouldn't be set to 0 anyway + */ + if (req->rq_transno == 0) + CERROR("Transno is 0 during replay!\n"); + + /* continue with recovery */ + rc = ptlrpc_import_recovery_state_machine(imp); + out: + req->rq_send_state = aa->praa_old_state; + + if (rc != 0) + /* this replay failed, so restart recovery */ + ptlrpc_connect_import(imp); + + return rc; +} + +/** + * Prepares and queues request for replay. + * Adds it to ptlrpcd queue for actual sending. + * Returns 0 on success. + */ +int ptlrpc_replay_req(struct ptlrpc_request *req) +{ + struct ptlrpc_replay_async_args *aa; + + LASSERT(req->rq_import->imp_state == LUSTRE_IMP_REPLAY); + + LASSERT(sizeof(*aa) <= sizeof(req->rq_async_args)); + aa = ptlrpc_req_async_args(req); + memset(aa, 0, sizeof(*aa)); + + /* Prepare request to be resent with ptlrpcd */ + aa->praa_old_state = req->rq_send_state; + req->rq_send_state = LUSTRE_IMP_REPLAY; + req->rq_phase = RQ_PHASE_NEW; + req->rq_next_phase = RQ_PHASE_UNDEFINED; + if (req->rq_repmsg) + aa->praa_old_status = lustre_msg_get_status(req->rq_repmsg); + req->rq_status = 0; + req->rq_interpret_reply = ptlrpc_replay_interpret; + /* Readjust the timeout for current conditions */ + ptlrpc_at_set_req_timeout(req); + + /* Tell server the net_latency, so the server can calculate how long + * it should wait for next replay */ + lustre_msg_set_service_time(req->rq_reqmsg, + ptlrpc_at_get_net_latency(req)); + DEBUG_REQ(D_HA, req, "REPLAY"); + + atomic_inc(&req->rq_import->imp_replay_inflight); + ptlrpc_request_addref(req); /* ptlrpcd needs a ref */ + + ptlrpcd_add_req(req, PDL_POLICY_LOCAL, -1); + return 0; +} +EXPORT_SYMBOL(ptlrpc_replay_req); + +/** + * Aborts all in-flight request on import \a imp sending and delayed lists + */ +void ptlrpc_abort_inflight(struct obd_import *imp) +{ + struct list_head *tmp, *n; + + /* Make sure that no new requests get processed for this import. + * ptlrpc_{queue,set}_wait must (and does) hold imp_lock while testing + * this flag and then putting requests on sending_list or delayed_list. + */ + spin_lock(&imp->imp_lock); + + /* XXX locking? Maybe we should remove each request with the list + * locked? Also, how do we know if the requests on the list are + * being freed at this time? + */ + list_for_each_safe(tmp, n, &imp->imp_sending_list) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, rq_list); + + DEBUG_REQ(D_RPCTRACE, req, "inflight"); + + spin_lock(&req->rq_lock); + if (req->rq_import_generation < imp->imp_generation) { + req->rq_err = 1; + req->rq_status = -EIO; + ptlrpc_client_wake_req(req); + } + spin_unlock(&req->rq_lock); + } + + list_for_each_safe(tmp, n, &imp->imp_delayed_list) { + struct ptlrpc_request *req = + list_entry(tmp, struct ptlrpc_request, rq_list); + + DEBUG_REQ(D_RPCTRACE, req, "aborting waiting req"); + + spin_lock(&req->rq_lock); + if (req->rq_import_generation < imp->imp_generation) { + req->rq_err = 1; + req->rq_status = -EIO; + ptlrpc_client_wake_req(req); + } + spin_unlock(&req->rq_lock); + } + + /* Last chance to free reqs left on the replay list, but we + * will still leak reqs that haven't committed. */ + if (imp->imp_replayable) + ptlrpc_free_committed(imp); + + spin_unlock(&imp->imp_lock); +} +EXPORT_SYMBOL(ptlrpc_abort_inflight); + +/** + * Abort all uncompleted requests in request set \a set + */ +void ptlrpc_abort_set(struct ptlrpc_request_set *set) +{ + struct list_head *tmp, *pos; + + LASSERT(set != NULL); + + list_for_each_safe(pos, tmp, &set->set_requests) { + struct ptlrpc_request *req = + list_entry(pos, struct ptlrpc_request, + rq_set_chain); + + spin_lock(&req->rq_lock); + if (req->rq_phase != RQ_PHASE_RPC) { + spin_unlock(&req->rq_lock); + continue; + } + + req->rq_err = 1; + req->rq_status = -EINTR; + ptlrpc_client_wake_req(req); + spin_unlock(&req->rq_lock); + } +} + +static __u64 ptlrpc_last_xid; +static spinlock_t ptlrpc_last_xid_lock; + +/** + * Initialize the XID for the node. This is common among all requests on + * this node, and only requires the property that it is monotonically + * increasing. It does not need to be sequential. Since this is also used + * as the RDMA match bits, it is important that a single client NOT have + * the same match bits for two different in-flight requests, hence we do + * NOT want to have an XID per target or similar. + * + * To avoid an unlikely collision between match bits after a client reboot + * (which would deliver old data into the wrong RDMA buffer) initialize + * the XID based on the current time, assuming a maximum RPC rate of 1M RPC/s. + * If the time is clearly incorrect, we instead use a 62-bit random number. + * In the worst case the random number will overflow 1M RPCs per second in + * 9133 years, or permutations thereof. + */ +#define YEAR_2004 (1ULL << 30) +void ptlrpc_init_xid(void) +{ + time_t now = get_seconds(); + + spin_lock_init(&ptlrpc_last_xid_lock); + if (now < YEAR_2004) { + cfs_get_random_bytes(&ptlrpc_last_xid, sizeof(ptlrpc_last_xid)); + ptlrpc_last_xid >>= 2; + ptlrpc_last_xid |= (1ULL << 61); + } else { + ptlrpc_last_xid = (__u64)now << 20; + } + + /* Always need to be aligned to a power-of-two for multi-bulk BRW */ + CLASSERT((PTLRPC_BULK_OPS_COUNT & (PTLRPC_BULK_OPS_COUNT - 1)) == 0); + ptlrpc_last_xid &= PTLRPC_BULK_OPS_MASK; +} + +/** + * Increase xid and returns resulting new value to the caller. + * + * Multi-bulk BRW RPCs consume multiple XIDs for each bulk transfer, starting + * at the returned xid, up to xid + PTLRPC_BULK_OPS_COUNT - 1. The BRW RPC + * itself uses the last bulk xid needed, so the server can determine the + * the number of bulk transfers from the RPC XID and a bitmask. The starting + * xid must align to a power-of-two value. + * + * This is assumed to be true due to the initial ptlrpc_last_xid + * value also being initialized to a power-of-two value. LU-1431 + */ +__u64 ptlrpc_next_xid(void) +{ + __u64 next; + + spin_lock(&ptlrpc_last_xid_lock); + next = ptlrpc_last_xid + PTLRPC_BULK_OPS_COUNT; + ptlrpc_last_xid = next; + spin_unlock(&ptlrpc_last_xid_lock); + + return next; +} +EXPORT_SYMBOL(ptlrpc_next_xid); + +/** + * Get a glimpse at what next xid value might have been. + * Returns possible next xid. + */ +__u64 ptlrpc_sample_next_xid(void) +{ +#if BITS_PER_LONG == 32 + /* need to avoid possible word tearing on 32-bit systems */ + __u64 next; + + spin_lock(&ptlrpc_last_xid_lock); + next = ptlrpc_last_xid + PTLRPC_BULK_OPS_COUNT; + spin_unlock(&ptlrpc_last_xid_lock); + + return next; +#else + /* No need to lock, since returned value is racy anyways */ + return ptlrpc_last_xid + PTLRPC_BULK_OPS_COUNT; +#endif +} +EXPORT_SYMBOL(ptlrpc_sample_next_xid); + +/** + * Functions for operating ptlrpc workers. + * + * A ptlrpc work is a function which will be running inside ptlrpc context. + * The callback shouldn't sleep otherwise it will block that ptlrpcd thread. + * + * 1. after a work is created, it can be used many times, that is: + * handler = ptlrpcd_alloc_work(); + * ptlrpcd_queue_work(); + * + * queue it again when necessary: + * ptlrpcd_queue_work(); + * ptlrpcd_destroy_work(); + * 2. ptlrpcd_queue_work() can be called by multiple processes meanwhile, but + * it will only be queued once in any time. Also as its name implies, it may + * have delay before it really runs by ptlrpcd thread. + */ +struct ptlrpc_work_async_args { + int (*cb)(const struct lu_env *, void *); + void *cbdata; +}; + +static void ptlrpcd_add_work_req(struct ptlrpc_request *req) +{ + /* re-initialize the req */ + req->rq_timeout = obd_timeout; + req->rq_sent = get_seconds(); + req->rq_deadline = req->rq_sent + req->rq_timeout; + req->rq_reply_deadline = req->rq_deadline; + req->rq_phase = RQ_PHASE_INTERPRET; + req->rq_next_phase = RQ_PHASE_COMPLETE; + req->rq_xid = ptlrpc_next_xid(); + req->rq_import_generation = req->rq_import->imp_generation; + + ptlrpcd_add_req(req, PDL_POLICY_ROUND, -1); +} + +static int work_interpreter(const struct lu_env *env, + struct ptlrpc_request *req, void *data, int rc) +{ + struct ptlrpc_work_async_args *arg = data; + + LASSERT(ptlrpcd_check_work(req)); + LASSERT(arg->cb != NULL); + + rc = arg->cb(env, arg->cbdata); + + list_del_init(&req->rq_set_chain); + req->rq_set = NULL; + + if (atomic_dec_return(&req->rq_refcount) > 1) { + atomic_set(&req->rq_refcount, 2); + ptlrpcd_add_work_req(req); + } + return rc; +} + +static int worker_format; + +static int ptlrpcd_check_work(struct ptlrpc_request *req) +{ + return req->rq_pill.rc_fmt == (void *)&worker_format; +} + +/** + * Create a work for ptlrpc. + */ +void *ptlrpcd_alloc_work(struct obd_import *imp, + int (*cb)(const struct lu_env *, void *), void *cbdata) +{ + struct ptlrpc_request *req = NULL; + struct ptlrpc_work_async_args *args; + + might_sleep(); + + if (cb == NULL) + return ERR_PTR(-EINVAL); + + /* copy some code from deprecated fakereq. */ + req = ptlrpc_request_cache_alloc(GFP_NOFS); + if (req == NULL) { + CERROR("ptlrpc: run out of memory!\n"); + return ERR_PTR(-ENOMEM); + } + + req->rq_send_state = LUSTRE_IMP_FULL; + req->rq_type = PTL_RPC_MSG_REQUEST; + req->rq_import = class_import_get(imp); + req->rq_export = NULL; + req->rq_interpret_reply = work_interpreter; + /* don't want reply */ + req->rq_receiving_reply = 0; + req->rq_req_unlink = req->rq_reply_unlink = 0; + req->rq_no_delay = req->rq_no_resend = 1; + req->rq_pill.rc_fmt = (void *)&worker_format; + + spin_lock_init(&req->rq_lock); + INIT_LIST_HEAD(&req->rq_list); + INIT_LIST_HEAD(&req->rq_replay_list); + INIT_LIST_HEAD(&req->rq_set_chain); + INIT_LIST_HEAD(&req->rq_history_list); + INIT_LIST_HEAD(&req->rq_exp_list); + init_waitqueue_head(&req->rq_reply_waitq); + init_waitqueue_head(&req->rq_set_waitq); + atomic_set(&req->rq_refcount, 1); + + CLASSERT(sizeof(*args) <= sizeof(req->rq_async_args)); + args = ptlrpc_req_async_args(req); + args->cb = cb; + args->cbdata = cbdata; + + return req; +} +EXPORT_SYMBOL(ptlrpcd_alloc_work); + +void ptlrpcd_destroy_work(void *handler) +{ + struct ptlrpc_request *req = handler; + + if (req) + ptlrpc_req_finished(req); +} +EXPORT_SYMBOL(ptlrpcd_destroy_work); + +int ptlrpcd_queue_work(void *handler) +{ + struct ptlrpc_request *req = handler; + + /* + * Check if the req is already being queued. + * + * Here comes a trick: it lacks a way of checking if a req is being + * processed reliably in ptlrpc. Here I have to use refcount of req + * for this purpose. This is okay because the caller should use this + * req as opaque data. - Jinshan + */ + LASSERT(atomic_read(&req->rq_refcount) > 0); + if (atomic_inc_return(&req->rq_refcount) == 2) + ptlrpcd_add_work_req(req); + return 0; +} +EXPORT_SYMBOL(ptlrpcd_queue_work); |