/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * * 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 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * This file is part of Lustre, http://www.lustre.org/ * Lustre is a trademark of Sun Microsystems, Inc. * * Implementation of cl_page for OSC layer. * * Author: Nikita Danilov */ /** \addtogroup osc osc @{ */ #define DEBUG_SUBSYSTEM S_OSC #include "osc_cl_internal.h" /* * Comment out osc_page_protected because it may sleep inside the * the client_obd_list_lock. * client_obd_list_lock -> osc_ap_completion -> osc_completion -> * -> osc_page_protected -> osc_page_is_dlocked -> osc_match_base * -> ldlm_lock_match -> sptlrpc_import_check_ctx -> sleep. */ #if 0 static int osc_page_is_dlocked(const struct lu_env *env, const struct osc_page *opg, enum cl_lock_mode mode, int pending, int unref) { struct cl_page *page; struct osc_object *obj; struct osc_thread_info *info; struct ldlm_res_id *resname; struct lustre_handle *lockh; ldlm_policy_data_t *policy; ldlm_mode_t dlmmode; int flags; might_sleep(); info = osc_env_info(env); resname = &info->oti_resname; policy = &info->oti_policy; lockh = &info->oti_handle; page = opg->ops_cl.cpl_page; obj = cl2osc(opg->ops_cl.cpl_obj); flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED; if (pending) flags |= LDLM_FL_CBPENDING; dlmmode = osc_cl_lock2ldlm(mode) | LCK_PW; osc_lock_build_res(env, obj, resname); osc_index2policy(policy, page->cp_obj, page->cp_index, page->cp_index); return osc_match_base(osc_export(obj), resname, LDLM_EXTENT, policy, dlmmode, &flags, NULL, lockh, unref); } /** * Checks an invariant that a page in the cache is covered by a lock, as * needed. */ static int osc_page_protected(const struct lu_env *env, const struct osc_page *opg, enum cl_lock_mode mode, int unref) { struct cl_object_header *hdr; struct cl_lock *scan; struct cl_page *page; struct cl_lock_descr *descr; int result; LINVRNT(!opg->ops_temp); page = opg->ops_cl.cpl_page; if (page->cp_owner != NULL && cl_io_top(page->cp_owner)->ci_lockreq == CILR_NEVER) /* * If IO is done without locks (liblustre, or lloop), lock is * not required. */ result = 1; else /* otherwise check for a DLM lock */ result = osc_page_is_dlocked(env, opg, mode, 1, unref); if (result == 0) { /* maybe this page is a part of a lockless io? */ hdr = cl_object_header(opg->ops_cl.cpl_obj); descr = &osc_env_info(env)->oti_descr; descr->cld_mode = mode; descr->cld_start = page->cp_index; descr->cld_end = page->cp_index; spin_lock(&hdr->coh_lock_guard); list_for_each_entry(scan, &hdr->coh_locks, cll_linkage) { /* * Lock-less sub-lock has to be either in HELD state * (when io is actively going on), or in CACHED state, * when top-lock is being unlocked: * cl_io_unlock()->cl_unuse()->...->lov_lock_unuse(). */ if ((scan->cll_state == CLS_HELD || scan->cll_state == CLS_CACHED) && cl_lock_ext_match(&scan->cll_descr, descr)) { struct osc_lock *olck; olck = osc_lock_at(scan); result = osc_lock_is_lockless(olck); break; } } spin_unlock(&hdr->coh_lock_guard); } return result; } #else static int osc_page_protected(const struct lu_env *env, const struct osc_page *opg, enum cl_lock_mode mode, int unref) { return 1; } #endif /***************************************************************************** * * Page operations. * */ static void osc_page_fini(const struct lu_env *env, struct cl_page_slice *slice) { struct osc_page *opg = cl2osc_page(slice); CDEBUG(D_TRACE, "%p\n", opg); OBD_SLAB_FREE_PTR(opg, osc_page_kmem); } static void osc_page_transfer_get(struct osc_page *opg, const char *label) { struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); LASSERT(!opg->ops_transfer_pinned); cl_page_get(page); lu_ref_add_atomic(&page->cp_reference, label, page); opg->ops_transfer_pinned = 1; } static void osc_page_transfer_put(const struct lu_env *env, struct osc_page *opg) { struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); if (opg->ops_transfer_pinned) { lu_ref_del(&page->cp_reference, "transfer", page); opg->ops_transfer_pinned = 0; cl_page_put(env, page); } } /** * This is called once for every page when it is submitted for a transfer * either opportunistic (osc_page_cache_add()), or immediate * (osc_page_submit()). */ static void osc_page_transfer_add(const struct lu_env *env, struct osc_page *opg, enum cl_req_type crt) { struct osc_object *obj; LINVRNT(cl_page_is_vmlocked(env, opg->ops_cl.cpl_page)); obj = cl2osc(opg->ops_cl.cpl_obj); spin_lock(&obj->oo_seatbelt); list_add(&opg->ops_inflight, &obj->oo_inflight[crt]); opg->ops_submitter = cfs_current(); spin_unlock(&obj->oo_seatbelt); } static int osc_page_cache_add(const struct lu_env *env, const struct cl_page_slice *slice, struct cl_io *unused) { struct osc_page *opg = cl2osc_page(slice); struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj); struct osc_io *oio = osc_env_io(env); int result; int brw_flags; int noquota = 0; LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 0)); ENTRY; /* Set the OBD_BRW_SRVLOCK before the page is queued. */ brw_flags = osc_io_srvlock(oio) ? OBD_BRW_SRVLOCK : 0; if (!client_is_remote(osc_export(obj)) && cfs_capable(CFS_CAP_SYS_RESOURCE)) { brw_flags |= OBD_BRW_NOQUOTA; noquota = OBD_BRW_NOQUOTA; } osc_page_transfer_get(opg, "transfer\0cache"); result = osc_queue_async_io(env, osc_export(obj), NULL, obj->oo_oinfo, &opg->ops_oap, OBD_BRW_WRITE | noquota, 0, 0, brw_flags, 0); if (result != 0) osc_page_transfer_put(env, opg); else osc_page_transfer_add(env, opg, CRT_WRITE); RETURN(result); } void osc_index2policy(ldlm_policy_data_t *policy, const struct cl_object *obj, pgoff_t start, pgoff_t end) { memset(policy, 0, sizeof *policy); policy->l_extent.start = cl_offset(obj, start); policy->l_extent.end = cl_offset(obj, end + 1) - 1; } static int osc_page_is_under_lock(const struct lu_env *env, const struct cl_page_slice *slice, struct cl_io *unused) { struct cl_lock *lock; int result; ENTRY; lock = cl_lock_at_page(env, slice->cpl_obj, slice->cpl_page, NULL, 1, 0); if (lock != NULL) { cl_lock_put(env, lock); result = -EBUSY; } else result = -ENODATA; RETURN(result); } static int osc_page_fail(const struct lu_env *env, const struct cl_page_slice *slice, struct cl_io *unused) { /* * Cached read? */ LBUG(); return 0; } static const char *osc_list(struct list_head *head) { return list_empty(head) ? "-" : "+"; } static inline cfs_time_t osc_submit_duration(struct osc_page *opg) { if (opg->ops_submit_time == 0) return 0; return (cfs_time_current() - opg->ops_submit_time); } static int osc_page_print(const struct lu_env *env, const struct cl_page_slice *slice, void *cookie, lu_printer_t printer) { struct osc_page *opg = cl2osc_page(slice); struct osc_async_page *oap = &opg->ops_oap; struct osc_object *obj = cl2osc(slice->cpl_obj); struct client_obd *cli = &osc_export(obj)->exp_obd->u.cli; struct lov_oinfo *loi = obj->oo_oinfo; return (*printer)(env, cookie, LUSTRE_OSC_NAME"-page@%p: " "1< %#x %d %u %s %s %s > " "2< %llu %u %#x %#x | %p %p %p %p %p > " "3< %s %p %d %lu > " "4< %d %d %d %lu %s | %s %s %s %s > " "5< %s %s %s %s | %d %s %s | %d %s %s>\n", opg, /* 1 */ oap->oap_magic, oap->oap_cmd, oap->oap_interrupted, osc_list(&oap->oap_pending_item), osc_list(&oap->oap_urgent_item), osc_list(&oap->oap_rpc_item), /* 2 */ oap->oap_obj_off, oap->oap_page_off, oap->oap_async_flags, oap->oap_brw_flags, oap->oap_request, oap->oap_cli, oap->oap_loi, oap->oap_caller_ops, oap->oap_caller_data, /* 3 */ osc_list(&opg->ops_inflight), opg->ops_submitter, opg->ops_transfer_pinned, osc_submit_duration(opg), /* 4 */ cli->cl_r_in_flight, cli->cl_w_in_flight, cli->cl_max_rpcs_in_flight, cli->cl_avail_grant, osc_list(&cli->cl_cache_waiters), osc_list(&cli->cl_loi_ready_list), osc_list(&cli->cl_loi_hp_ready_list), osc_list(&cli->cl_loi_write_list), osc_list(&cli->cl_loi_read_list), /* 5 */ osc_list(&loi->loi_ready_item), osc_list(&loi->loi_hp_ready_item), osc_list(&loi->loi_write_item), osc_list(&loi->loi_read_item), loi->loi_read_lop.lop_num_pending, osc_list(&loi->loi_read_lop.lop_pending), osc_list(&loi->loi_read_lop.lop_urgent), loi->loi_write_lop.lop_num_pending, osc_list(&loi->loi_write_lop.lop_pending), osc_list(&loi->loi_write_lop.lop_urgent)); } static void osc_page_delete(const struct lu_env *env, const struct cl_page_slice *slice) { struct osc_page *opg = cl2osc_page(slice); struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj); struct osc_async_page *oap = &opg->ops_oap; int rc; LINVRNT(opg->ops_temp || osc_page_protected(env, opg, CLM_READ, 1)); ENTRY; CDEBUG(D_TRACE, "%p\n", opg); osc_page_transfer_put(env, opg); rc = osc_teardown_async_page(osc_export(obj), NULL, obj->oo_oinfo, oap); if (rc) { CL_PAGE_DEBUG(D_ERROR, env, cl_page_top(slice->cpl_page), "Trying to teardown failed: %d\n", rc); LASSERT(0); } spin_lock(&obj->oo_seatbelt); list_del_init(&opg->ops_inflight); spin_unlock(&obj->oo_seatbelt); EXIT; } void osc_page_clip(const struct lu_env *env, const struct cl_page_slice *slice, int from, int to) { struct osc_page *opg = cl2osc_page(slice); struct osc_async_page *oap = &opg->ops_oap; LINVRNT(osc_page_protected(env, opg, CLM_READ, 0)); opg->ops_from = from; opg->ops_to = to; spin_lock(&oap->oap_lock); oap->oap_async_flags |= ASYNC_COUNT_STABLE; spin_unlock(&oap->oap_lock); } static int osc_page_cancel(const struct lu_env *env, const struct cl_page_slice *slice) { struct osc_page *opg = cl2osc_page(slice); struct osc_async_page *oap = &opg->ops_oap; int rc = 0; LINVRNT(osc_page_protected(env, opg, CLM_READ, 0)); client_obd_list_lock(&oap->oap_cli->cl_loi_list_lock); /* Check if the transferring against this page * is completed, or not even queued. */ if (opg->ops_transfer_pinned) /* FIXME: may not be interrupted.. */ rc = osc_oap_interrupted(env, oap); LASSERT(ergo(rc == 0, opg->ops_transfer_pinned == 0)); client_obd_list_unlock(&oap->oap_cli->cl_loi_list_lock); return rc; } static const struct cl_page_operations osc_page_ops = { .cpo_fini = osc_page_fini, .cpo_print = osc_page_print, .cpo_delete = osc_page_delete, .cpo_is_under_lock = osc_page_is_under_lock, .io = { [CRT_READ] = { .cpo_cache_add = osc_page_fail }, [CRT_WRITE] = { .cpo_cache_add = osc_page_cache_add } }, .cpo_clip = osc_page_clip, .cpo_cancel = osc_page_cancel }; static int osc_make_ready(const struct lu_env *env, void *data, int cmd) { struct osc_page *opg = data; struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); int result; LASSERT(cmd == OBD_BRW_WRITE); /* no cached reads */ LINVRNT(osc_page_protected(env, opg, CLM_WRITE, 1)); ENTRY; result = cl_page_make_ready(env, page, CRT_WRITE); if (result == 0) opg->ops_submit_time = cfs_time_current(); RETURN(result); } static int osc_refresh_count(const struct lu_env *env, void *data, int cmd) { struct cl_page *page; struct osc_page *osc = data; struct cl_object *obj; struct cl_attr *attr = &osc_env_info(env)->oti_attr; int result; loff_t kms; LINVRNT(osc_page_protected(env, osc, CLM_READ, 1)); /* readpage queues with _COUNT_STABLE, shouldn't get here. */ LASSERT(!(cmd & OBD_BRW_READ)); LASSERT(osc != NULL); page = osc->ops_cl.cpl_page; obj = osc->ops_cl.cpl_obj; cl_object_attr_lock(obj); result = cl_object_attr_get(env, obj, attr); cl_object_attr_unlock(obj); if (result < 0) return result; kms = attr->cat_kms; if (cl_offset(obj, page->cp_index) >= kms) /* catch race with truncate */ return 0; else if (cl_offset(obj, page->cp_index + 1) > kms) /* catch sub-page write at end of file */ return kms % CFS_PAGE_SIZE; else return CFS_PAGE_SIZE; } static int osc_completion(const struct lu_env *env, void *data, int cmd, struct obdo *oa, int rc) { struct osc_page *opg = data; struct osc_async_page *oap = &opg->ops_oap; struct cl_page *page = cl_page_top(opg->ops_cl.cpl_page); struct osc_object *obj = cl2osc(opg->ops_cl.cpl_obj); enum cl_req_type crt; LINVRNT(osc_page_protected(env, opg, CLM_READ, 1)); LINVRNT(cl_page_is_vmlocked(env, page)); ENTRY; cmd &= ~OBD_BRW_NOQUOTA; LASSERT(equi(page->cp_state == CPS_PAGEIN, cmd == OBD_BRW_READ)); LASSERT(equi(page->cp_state == CPS_PAGEOUT, cmd == OBD_BRW_WRITE)); LASSERT(opg->ops_transfer_pinned); /* * page->cp_req can be NULL if io submission failed before * cl_req was allocated. */ if (page->cp_req != NULL) cl_req_page_done(env, page); LASSERT(page->cp_req == NULL); /* As the transfer for this page is being done, clear the flags */ spin_lock(&oap->oap_lock); oap->oap_async_flags = 0; spin_unlock(&oap->oap_lock); crt = cmd == OBD_BRW_READ ? CRT_READ : CRT_WRITE; /* Clear opg->ops_transfer_pinned before VM lock is released. */ opg->ops_transfer_pinned = 0; spin_lock(&obj->oo_seatbelt); LASSERT(opg->ops_submitter != NULL); LASSERT(!list_empty(&opg->ops_inflight)); list_del_init(&opg->ops_inflight); spin_unlock(&obj->oo_seatbelt); opg->ops_submit_time = 0; cl_page_completion(env, page, crt, rc); /* statistic */ if (rc == 0 && oap->oap_brw_flags & OBD_BRW_SRVLOCK) { struct lu_device *ld = opg->ops_cl.cpl_obj->co_lu.lo_dev; struct osc_stats *stats = &lu2osc_dev(ld)->od_stats; int bytes = opg->ops_to - opg->ops_from; if (crt == CRT_READ) stats->os_lockless_reads += bytes; else stats->os_lockless_writes += bytes; } /* * This has to be the last operation with the page, as locks are * released in cl_page_completion() and nothing except for the * reference counter protects page from concurrent reclaim. */ lu_ref_del(&page->cp_reference, "transfer", page); /* * As page->cp_obj is pinned by a reference from page->cp_req, it is * safe to call cl_page_put() without risking object destruction in a * non-blocking context. */ cl_page_put(env, page); RETURN(0); } const static struct obd_async_page_ops osc_async_page_ops = { .ap_make_ready = osc_make_ready, .ap_refresh_count = osc_refresh_count, .ap_completion = osc_completion }; struct cl_page *osc_page_init(const struct lu_env *env, struct cl_object *obj, struct cl_page *page, cfs_page_t *vmpage) { struct osc_object *osc = cl2osc(obj); struct osc_page *opg; int result; OBD_SLAB_ALLOC_PTR_GFP(opg, osc_page_kmem, CFS_ALLOC_IO); if (opg != NULL) { void *oap = &opg->ops_oap; opg->ops_from = 0; opg->ops_to = CFS_PAGE_SIZE; result = osc_prep_async_page(osc_export(osc), NULL, osc->oo_oinfo, vmpage, cl_offset(obj, page->cp_index), &osc_async_page_ops, opg, (void **)&oap, 1, NULL); if (result == 0) cl_page_slice_add(page, &opg->ops_cl, obj, &osc_page_ops); /* * Cannot assert osc_page_protected() here as read-ahead * creates temporary pages outside of a lock. */ #ifdef INVARIANT_CHECK opg->ops_temp = !osc_page_protected(env, opg, CLM_READ, 1); #endif CFS_INIT_LIST_HEAD(&opg->ops_inflight); } else result = -ENOMEM; return ERR_PTR(result); } /** * Helper function called by osc_io_submit() for every page in an immediate * transfer (i.e., transferred synchronously). */ void osc_io_submit_page(const struct lu_env *env, struct osc_io *oio, struct osc_page *opg, enum cl_req_type crt) { struct osc_async_page *oap = &opg->ops_oap; struct client_obd *cli = oap->oap_cli; int flags = 0; LINVRNT(osc_page_protected(env, opg, crt == CRT_WRITE ? CLM_WRITE : CLM_READ, 1)); oap->oap_page_off = opg->ops_from; oap->oap_count = opg->ops_to - opg->ops_from; /* Give a hint to OST that requests are coming from kswapd - bug19529 */ if (libcfs_memory_pressure_get()) oap->oap_brw_flags |= OBD_BRW_MEMALLOC; oap->oap_brw_flags |= OBD_BRW_SYNC; if (osc_io_srvlock(oio)) oap->oap_brw_flags |= OBD_BRW_SRVLOCK; oap->oap_cmd = crt == CRT_WRITE ? OBD_BRW_WRITE : OBD_BRW_READ; if (!client_is_remote(osc_export(cl2osc(opg->ops_cl.cpl_obj))) && cfs_capable(CFS_CAP_SYS_RESOURCE)) { oap->oap_brw_flags |= OBD_BRW_NOQUOTA; oap->oap_cmd |= OBD_BRW_NOQUOTA; } if (oap->oap_cmd & OBD_BRW_READ) flags = ASYNC_COUNT_STABLE; else if (!(oap->oap_brw_page.flag & OBD_BRW_FROM_GRANT)) osc_enter_cache_try(env, cli, oap->oap_loi, oap, 1); spin_lock(&oap->oap_lock); oap->oap_async_flags |= OSC_FLAGS | flags; spin_unlock(&oap->oap_lock); osc_oap_to_pending(oap); osc_page_transfer_get(opg, "transfer\0imm"); osc_page_transfer_add(env, opg, crt); } /** @} osc */