1530 lines
41 KiB
C
1530 lines
41 KiB
C
/*
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* GPL HEADER START
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*
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 only,
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License version 2 for more details (a copy is included
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* in the LICENSE file that accompanied this code).
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*
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* You should have received a copy of the GNU General Public License
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* version 2 along with this program; If not, see
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* http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*
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* GPL HEADER END
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*/
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/*
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* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
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* Use is subject to license terms.
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*
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* Copyright (c) 2011, 2015, Intel Corporation.
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*/
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/*
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* This file is part of Lustre, http://www.lustre.org/
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* Lustre is a trademark of Sun Microsystems, Inc.
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*
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* Client Lustre Page.
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*
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* Author: Nikita Danilov <nikita.danilov@sun.com>
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*/
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#define DEBUG_SUBSYSTEM S_CLASS
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#include "../../include/linux/libcfs/libcfs.h"
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#include "../include/obd_class.h"
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#include "../include/obd_support.h"
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#include <linux/list.h>
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#include "../include/cl_object.h"
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#include "cl_internal.h"
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static void cl_page_delete0(const struct lu_env *env, struct cl_page *pg,
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int radix);
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# define PASSERT(env, page, expr) \
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do { \
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if (unlikely(!(expr))) { \
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CL_PAGE_DEBUG(D_ERROR, (env), (page), #expr "\n"); \
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LASSERT(0); \
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} \
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} while (0)
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# define PINVRNT(env, page, exp) \
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((void)sizeof(env), (void)sizeof(page), (void)sizeof !!(exp))
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/**
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* Internal version of cl_page_top, it should be called if the page is
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* known to be not freed, says with page referenced, or radix tree lock held,
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* or page owned.
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*/
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static struct cl_page *cl_page_top_trusted(struct cl_page *page)
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{
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while (page->cp_parent)
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page = page->cp_parent;
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return page;
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}
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/**
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* Internal version of cl_page_get().
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*
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* This function can be used to obtain initial reference to previously
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* unreferenced cached object. It can be called only if concurrent page
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* reclamation is somehow prevented, e.g., by locking page radix-tree
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* (cl_object_header::hdr->coh_page_guard), or by keeping a lock on a VM page,
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* associated with \a page.
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*
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* Use with care! Not exported.
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*/
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static void cl_page_get_trust(struct cl_page *page)
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{
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LASSERT(atomic_read(&page->cp_ref) > 0);
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atomic_inc(&page->cp_ref);
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}
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/**
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* Returns a slice within a page, corresponding to the given layer in the
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* device stack.
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*
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* \see cl_lock_at()
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*/
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static const struct cl_page_slice *
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cl_page_at_trusted(const struct cl_page *page,
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const struct lu_device_type *dtype)
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{
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const struct cl_page_slice *slice;
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page = cl_page_top_trusted((struct cl_page *)page);
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do {
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list_for_each_entry(slice, &page->cp_layers, cpl_linkage) {
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if (slice->cpl_obj->co_lu.lo_dev->ld_type == dtype)
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return slice;
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}
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page = page->cp_child;
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} while (page);
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return NULL;
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}
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/**
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* Returns a page with given index in the given object, or NULL if no page is
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* found. Acquires a reference on \a page.
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*
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* Locking: called under cl_object_header::coh_page_guard spin-lock.
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*/
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struct cl_page *cl_page_lookup(struct cl_object_header *hdr, pgoff_t index)
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{
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struct cl_page *page;
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assert_spin_locked(&hdr->coh_page_guard);
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page = radix_tree_lookup(&hdr->coh_tree, index);
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if (page)
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cl_page_get_trust(page);
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return page;
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}
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EXPORT_SYMBOL(cl_page_lookup);
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/**
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* Returns a list of pages by a given [start, end] of \a obj.
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*
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* \param resched If not NULL, then we give up before hogging CPU for too
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* long and set *resched = 1, in that case caller should implement a retry
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* logic.
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*
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* Gang tree lookup (radix_tree_gang_lookup()) optimization is absolutely
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* crucial in the face of [offset, EOF] locks.
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*
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* Return at least one page in @queue unless there is no covered page.
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*/
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int cl_page_gang_lookup(const struct lu_env *env, struct cl_object *obj,
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struct cl_io *io, pgoff_t start, pgoff_t end,
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cl_page_gang_cb_t cb, void *cbdata)
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{
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struct cl_object_header *hdr;
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struct cl_page *page;
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struct cl_page **pvec;
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const struct cl_page_slice *slice;
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const struct lu_device_type *dtype;
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pgoff_t idx;
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unsigned int nr;
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unsigned int i;
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unsigned int j;
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int res = CLP_GANG_OKAY;
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int tree_lock = 1;
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idx = start;
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hdr = cl_object_header(obj);
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pvec = cl_env_info(env)->clt_pvec;
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dtype = cl_object_top(obj)->co_lu.lo_dev->ld_type;
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spin_lock(&hdr->coh_page_guard);
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while ((nr = radix_tree_gang_lookup(&hdr->coh_tree, (void **)pvec,
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idx, CLT_PVEC_SIZE)) > 0) {
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int end_of_region = 0;
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idx = pvec[nr - 1]->cp_index + 1;
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for (i = 0, j = 0; i < nr; ++i) {
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page = pvec[i];
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pvec[i] = NULL;
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LASSERT(page->cp_type == CPT_CACHEABLE);
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if (page->cp_index > end) {
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end_of_region = 1;
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break;
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}
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if (page->cp_state == CPS_FREEING)
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continue;
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slice = cl_page_at_trusted(page, dtype);
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/*
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* Pages for lsm-less file has no underneath sub-page
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* for osc, in case of ...
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*/
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PASSERT(env, page, slice);
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page = slice->cpl_page;
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/*
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* Can safely call cl_page_get_trust() under
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* radix-tree spin-lock.
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*
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* XXX not true, because @page is from object another
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* than @hdr and protected by different tree lock.
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*/
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cl_page_get_trust(page);
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lu_ref_add_atomic(&page->cp_reference,
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"gang_lookup", current);
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pvec[j++] = page;
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}
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/*
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* Here a delicate locking dance is performed. Current thread
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* holds a reference to a page, but has to own it before it
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* can be placed into queue. Owning implies waiting, so
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* radix-tree lock is to be released. After a wait one has to
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* check that pages weren't truncated (cl_page_own() returns
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* error in the latter case).
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*/
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spin_unlock(&hdr->coh_page_guard);
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tree_lock = 0;
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for (i = 0; i < j; ++i) {
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page = pvec[i];
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if (res == CLP_GANG_OKAY)
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res = (*cb)(env, io, page, cbdata);
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lu_ref_del(&page->cp_reference,
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"gang_lookup", current);
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cl_page_put(env, page);
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}
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if (nr < CLT_PVEC_SIZE || end_of_region)
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break;
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if (res == CLP_GANG_OKAY && need_resched())
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res = CLP_GANG_RESCHED;
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if (res != CLP_GANG_OKAY)
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break;
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spin_lock(&hdr->coh_page_guard);
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tree_lock = 1;
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}
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if (tree_lock)
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spin_unlock(&hdr->coh_page_guard);
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return res;
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}
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EXPORT_SYMBOL(cl_page_gang_lookup);
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static void cl_page_free(const struct lu_env *env, struct cl_page *page)
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{
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struct cl_object *obj = page->cp_obj;
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PASSERT(env, page, list_empty(&page->cp_batch));
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PASSERT(env, page, !page->cp_owner);
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PASSERT(env, page, !page->cp_req);
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PASSERT(env, page, !page->cp_parent);
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PASSERT(env, page, page->cp_state == CPS_FREEING);
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might_sleep();
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while (!list_empty(&page->cp_layers)) {
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struct cl_page_slice *slice;
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slice = list_entry(page->cp_layers.next,
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struct cl_page_slice, cpl_linkage);
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list_del_init(page->cp_layers.next);
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slice->cpl_ops->cpo_fini(env, slice);
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}
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lu_object_ref_del_at(&obj->co_lu, &page->cp_obj_ref, "cl_page", page);
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cl_object_put(env, obj);
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lu_ref_fini(&page->cp_reference);
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kfree(page);
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}
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/**
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* Helper function updating page state. This is the only place in the code
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* where cl_page::cp_state field is mutated.
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*/
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static inline void cl_page_state_set_trust(struct cl_page *page,
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enum cl_page_state state)
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{
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/* bypass const. */
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*(enum cl_page_state *)&page->cp_state = state;
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}
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static struct cl_page *cl_page_alloc(const struct lu_env *env,
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struct cl_object *o, pgoff_t ind,
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struct page *vmpage,
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enum cl_page_type type)
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{
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struct cl_page *page;
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struct lu_object_header *head;
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page = kzalloc(cl_object_header(o)->coh_page_bufsize, GFP_NOFS);
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if (page) {
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int result = 0;
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atomic_set(&page->cp_ref, 1);
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if (type == CPT_CACHEABLE) /* for radix tree */
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atomic_inc(&page->cp_ref);
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page->cp_obj = o;
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cl_object_get(o);
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lu_object_ref_add_at(&o->co_lu, &page->cp_obj_ref, "cl_page",
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page);
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page->cp_index = ind;
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cl_page_state_set_trust(page, CPS_CACHED);
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page->cp_type = type;
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INIT_LIST_HEAD(&page->cp_layers);
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INIT_LIST_HEAD(&page->cp_batch);
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INIT_LIST_HEAD(&page->cp_flight);
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mutex_init(&page->cp_mutex);
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lu_ref_init(&page->cp_reference);
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head = o->co_lu.lo_header;
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list_for_each_entry(o, &head->loh_layers, co_lu.lo_linkage) {
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if (o->co_ops->coo_page_init) {
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result = o->co_ops->coo_page_init(env, o,
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page, vmpage);
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if (result != 0) {
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cl_page_delete0(env, page, 0);
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cl_page_free(env, page);
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page = ERR_PTR(result);
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break;
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}
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}
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}
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} else {
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page = ERR_PTR(-ENOMEM);
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}
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return page;
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}
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/**
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* Returns a cl_page with index \a idx at the object \a o, and associated with
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* the VM page \a vmpage.
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*
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* This is the main entry point into the cl_page caching interface. First, a
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* cache (implemented as a per-object radix tree) is consulted. If page is
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* found there, it is returned immediately. Otherwise new page is allocated
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* and returned. In any case, additional reference to page is acquired.
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*
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* \see cl_object_find(), cl_lock_find()
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*/
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static struct cl_page *cl_page_find0(const struct lu_env *env,
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struct cl_object *o,
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pgoff_t idx, struct page *vmpage,
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enum cl_page_type type,
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struct cl_page *parent)
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{
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struct cl_page *page = NULL;
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struct cl_page *ghost = NULL;
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struct cl_object_header *hdr;
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int err;
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LASSERT(type == CPT_CACHEABLE || type == CPT_TRANSIENT);
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might_sleep();
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hdr = cl_object_header(o);
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CDEBUG(D_PAGE, "%lu@"DFID" %p %lx %d\n",
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idx, PFID(&hdr->coh_lu.loh_fid), vmpage, vmpage->private, type);
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/* fast path. */
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if (type == CPT_CACHEABLE) {
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/*
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* vmpage lock is used to protect the child/parent
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* relationship
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*/
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KLASSERT(PageLocked(vmpage));
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/*
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* cl_vmpage_page() can be called here without any locks as
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*
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* - "vmpage" is locked (which prevents ->private from
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* concurrent updates), and
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*
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* - "o" cannot be destroyed while current thread holds a
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* reference on it.
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*/
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page = cl_vmpage_page(vmpage, o);
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PINVRNT(env, page,
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ergo(page,
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cl_page_vmpage(env, page) == vmpage &&
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(void *)radix_tree_lookup(&hdr->coh_tree,
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idx) == page));
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}
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if (page)
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return page;
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/* allocate and initialize cl_page */
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page = cl_page_alloc(env, o, idx, vmpage, type);
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if (IS_ERR(page))
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return page;
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if (type == CPT_TRANSIENT) {
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if (parent) {
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LASSERT(!page->cp_parent);
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page->cp_parent = parent;
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parent->cp_child = page;
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}
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return page;
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}
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/*
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* XXX optimization: use radix_tree_preload() here, and change tree
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* gfp mask to GFP_KERNEL in cl_object_header_init().
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*/
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spin_lock(&hdr->coh_page_guard);
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err = radix_tree_insert(&hdr->coh_tree, idx, page);
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if (err != 0) {
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ghost = page;
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/*
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* Noted by Jay: a lock on \a vmpage protects cl_page_find()
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* from this race, but
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*
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* 0. it's better to have cl_page interface "locally
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* consistent" so that its correctness can be reasoned
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* about without appealing to the (obscure world of) VM
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* locking.
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*
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* 1. handling this race allows ->coh_tree to remain
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* consistent even when VM locking is somehow busted,
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* which is very useful during diagnosing and debugging.
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*/
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page = ERR_PTR(err);
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CL_PAGE_DEBUG(D_ERROR, env, ghost,
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"fail to insert into radix tree: %d\n", err);
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} else {
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if (parent) {
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LASSERT(!page->cp_parent);
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page->cp_parent = parent;
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parent->cp_child = page;
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}
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hdr->coh_pages++;
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}
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spin_unlock(&hdr->coh_page_guard);
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if (unlikely(ghost)) {
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cl_page_delete0(env, ghost, 0);
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cl_page_free(env, ghost);
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}
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return page;
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}
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struct cl_page *cl_page_find(const struct lu_env *env, struct cl_object *o,
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pgoff_t idx, struct page *vmpage,
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enum cl_page_type type)
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{
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return cl_page_find0(env, o, idx, vmpage, type, NULL);
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}
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EXPORT_SYMBOL(cl_page_find);
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struct cl_page *cl_page_find_sub(const struct lu_env *env, struct cl_object *o,
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pgoff_t idx, struct page *vmpage,
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struct cl_page *parent)
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{
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return cl_page_find0(env, o, idx, vmpage, parent->cp_type, parent);
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}
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EXPORT_SYMBOL(cl_page_find_sub);
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static inline int cl_page_invariant(const struct cl_page *pg)
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{
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struct cl_object_header *header;
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struct cl_page *parent;
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struct cl_page *child;
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struct cl_io *owner;
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|
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/*
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* Page invariant is protected by a VM lock.
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*/
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LINVRNT(cl_page_is_vmlocked(NULL, pg));
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header = cl_object_header(pg->cp_obj);
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parent = pg->cp_parent;
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child = pg->cp_child;
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owner = pg->cp_owner;
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return cl_page_in_use(pg) &&
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ergo(parent, parent->cp_child == pg) &&
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ergo(child, child->cp_parent == pg) &&
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ergo(child, pg->cp_obj != child->cp_obj) &&
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ergo(parent, pg->cp_obj != parent->cp_obj) &&
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ergo(owner && parent,
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parent->cp_owner == pg->cp_owner->ci_parent) &&
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ergo(owner && child, child->cp_owner->ci_parent == owner) &&
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/*
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* Either page is early in initialization (has neither child
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* nor parent yet), or it is in the object radix tree.
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*/
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ergo(pg->cp_state < CPS_FREEING && pg->cp_type == CPT_CACHEABLE,
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(void *)radix_tree_lookup(&header->coh_tree,
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pg->cp_index) == pg ||
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(!child && !parent));
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}
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|
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static void cl_page_state_set0(const struct lu_env *env,
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struct cl_page *page, enum cl_page_state state)
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{
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enum cl_page_state old;
|
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|
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/*
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* Matrix of allowed state transitions [old][new], for sanity
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* checking.
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*/
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|
static const int allowed_transitions[CPS_NR][CPS_NR] = {
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[CPS_CACHED] = {
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[CPS_CACHED] = 0,
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[CPS_OWNED] = 1, /* io finds existing cached page */
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[CPS_PAGEIN] = 0,
|
|
[CPS_PAGEOUT] = 1, /* write-out from the cache */
|
|
[CPS_FREEING] = 1, /* eviction on the memory pressure */
|
|
},
|
|
[CPS_OWNED] = {
|
|
[CPS_CACHED] = 1, /* release to the cache */
|
|
[CPS_OWNED] = 0,
|
|
[CPS_PAGEIN] = 1, /* start read immediately */
|
|
[CPS_PAGEOUT] = 1, /* start write immediately */
|
|
[CPS_FREEING] = 1, /* lock invalidation or truncate */
|
|
},
|
|
[CPS_PAGEIN] = {
|
|
[CPS_CACHED] = 1, /* io completion */
|
|
[CPS_OWNED] = 0,
|
|
[CPS_PAGEIN] = 0,
|
|
[CPS_PAGEOUT] = 0,
|
|
[CPS_FREEING] = 0,
|
|
},
|
|
[CPS_PAGEOUT] = {
|
|
[CPS_CACHED] = 1, /* io completion */
|
|
[CPS_OWNED] = 0,
|
|
[CPS_PAGEIN] = 0,
|
|
[CPS_PAGEOUT] = 0,
|
|
[CPS_FREEING] = 0,
|
|
},
|
|
[CPS_FREEING] = {
|
|
[CPS_CACHED] = 0,
|
|
[CPS_OWNED] = 0,
|
|
[CPS_PAGEIN] = 0,
|
|
[CPS_PAGEOUT] = 0,
|
|
[CPS_FREEING] = 0,
|
|
}
|
|
};
|
|
|
|
old = page->cp_state;
|
|
PASSERT(env, page, allowed_transitions[old][state]);
|
|
CL_PAGE_HEADER(D_TRACE, env, page, "%d -> %d\n", old, state);
|
|
for (; page; page = page->cp_child) {
|
|
PASSERT(env, page, page->cp_state == old);
|
|
PASSERT(env, page,
|
|
equi(state == CPS_OWNED, page->cp_owner));
|
|
|
|
cl_page_state_set_trust(page, state);
|
|
}
|
|
}
|
|
|
|
static void cl_page_state_set(const struct lu_env *env,
|
|
struct cl_page *page, enum cl_page_state state)
|
|
{
|
|
cl_page_state_set0(env, page, state);
|
|
}
|
|
|
|
/**
|
|
* Acquires an additional reference to a page.
|
|
*
|
|
* This can be called only by caller already possessing a reference to \a
|
|
* page.
|
|
*
|
|
* \see cl_object_get(), cl_lock_get().
|
|
*/
|
|
void cl_page_get(struct cl_page *page)
|
|
{
|
|
cl_page_get_trust(page);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_get);
|
|
|
|
/**
|
|
* Releases a reference to a page.
|
|
*
|
|
* When last reference is released, page is returned to the cache, unless it
|
|
* is in cl_page_state::CPS_FREEING state, in which case it is immediately
|
|
* destroyed.
|
|
*
|
|
* \see cl_object_put(), cl_lock_put().
|
|
*/
|
|
void cl_page_put(const struct lu_env *env, struct cl_page *page)
|
|
{
|
|
PASSERT(env, page, atomic_read(&page->cp_ref) > !!page->cp_parent);
|
|
|
|
CL_PAGE_HEADER(D_TRACE, env, page, "%d\n",
|
|
atomic_read(&page->cp_ref));
|
|
|
|
if (atomic_dec_and_test(&page->cp_ref)) {
|
|
LASSERT(page->cp_state == CPS_FREEING);
|
|
|
|
LASSERT(atomic_read(&page->cp_ref) == 0);
|
|
PASSERT(env, page, !page->cp_owner);
|
|
PASSERT(env, page, list_empty(&page->cp_batch));
|
|
/*
|
|
* Page is no longer reachable by other threads. Tear
|
|
* it down.
|
|
*/
|
|
cl_page_free(env, page);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(cl_page_put);
|
|
|
|
/**
|
|
* Returns a VM page associated with a given cl_page.
|
|
*/
|
|
struct page *cl_page_vmpage(const struct lu_env *env, struct cl_page *page)
|
|
{
|
|
const struct cl_page_slice *slice;
|
|
|
|
/*
|
|
* Find uppermost layer with ->cpo_vmpage() method, and return its
|
|
* result.
|
|
*/
|
|
page = cl_page_top(page);
|
|
do {
|
|
list_for_each_entry(slice, &page->cp_layers, cpl_linkage) {
|
|
if (slice->cpl_ops->cpo_vmpage)
|
|
return slice->cpl_ops->cpo_vmpage(env, slice);
|
|
}
|
|
page = page->cp_child;
|
|
} while (page);
|
|
LBUG(); /* ->cpo_vmpage() has to be defined somewhere in the stack */
|
|
}
|
|
EXPORT_SYMBOL(cl_page_vmpage);
|
|
|
|
/**
|
|
* Returns a cl_page associated with a VM page, and given cl_object.
|
|
*/
|
|
struct cl_page *cl_vmpage_page(struct page *vmpage, struct cl_object *obj)
|
|
{
|
|
struct cl_page *top;
|
|
struct cl_page *page;
|
|
|
|
KLASSERT(PageLocked(vmpage));
|
|
|
|
/*
|
|
* NOTE: absence of races and liveness of data are guaranteed by page
|
|
* lock on a "vmpage". That works because object destruction has
|
|
* bottom-to-top pass.
|
|
*/
|
|
|
|
/*
|
|
* This loop assumes that ->private points to the top-most page. This
|
|
* can be rectified easily.
|
|
*/
|
|
top = (struct cl_page *)vmpage->private;
|
|
if (!top)
|
|
return NULL;
|
|
|
|
for (page = top; page; page = page->cp_child) {
|
|
if (cl_object_same(page->cp_obj, obj)) {
|
|
cl_page_get_trust(page);
|
|
break;
|
|
}
|
|
}
|
|
LASSERT(ergo(page, page->cp_type == CPT_CACHEABLE));
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL(cl_vmpage_page);
|
|
|
|
/**
|
|
* Returns the top-page for a given page.
|
|
*
|
|
* \see cl_object_top(), cl_io_top()
|
|
*/
|
|
struct cl_page *cl_page_top(struct cl_page *page)
|
|
{
|
|
return cl_page_top_trusted(page);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_top);
|
|
|
|
const struct cl_page_slice *cl_page_at(const struct cl_page *page,
|
|
const struct lu_device_type *dtype)
|
|
{
|
|
return cl_page_at_trusted(page, dtype);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_at);
|
|
|
|
#define CL_PAGE_OP(opname) offsetof(struct cl_page_operations, opname)
|
|
|
|
#define CL_PAGE_INVOKE(_env, _page, _op, _proto, ...) \
|
|
({ \
|
|
const struct lu_env *__env = (_env); \
|
|
struct cl_page *__page = (_page); \
|
|
const struct cl_page_slice *__scan; \
|
|
int __result; \
|
|
ptrdiff_t __op = (_op); \
|
|
int (*__method)_proto; \
|
|
\
|
|
__result = 0; \
|
|
__page = cl_page_top(__page); \
|
|
do { \
|
|
list_for_each_entry(__scan, &__page->cp_layers, \
|
|
cpl_linkage) { \
|
|
__method = *(void **)((char *)__scan->cpl_ops + \
|
|
__op); \
|
|
if (__method) { \
|
|
__result = (*__method)(__env, __scan, \
|
|
## __VA_ARGS__); \
|
|
if (__result != 0) \
|
|
break; \
|
|
} \
|
|
} \
|
|
__page = __page->cp_child; \
|
|
} while (__page && __result == 0); \
|
|
if (__result > 0) \
|
|
__result = 0; \
|
|
__result; \
|
|
})
|
|
|
|
#define CL_PAGE_INVOID(_env, _page, _op, _proto, ...) \
|
|
do { \
|
|
const struct lu_env *__env = (_env); \
|
|
struct cl_page *__page = (_page); \
|
|
const struct cl_page_slice *__scan; \
|
|
ptrdiff_t __op = (_op); \
|
|
void (*__method)_proto; \
|
|
\
|
|
__page = cl_page_top(__page); \
|
|
do { \
|
|
list_for_each_entry(__scan, &__page->cp_layers, \
|
|
cpl_linkage) { \
|
|
__method = *(void **)((char *)__scan->cpl_ops + \
|
|
__op); \
|
|
if (__method) \
|
|
(*__method)(__env, __scan, \
|
|
## __VA_ARGS__); \
|
|
} \
|
|
__page = __page->cp_child; \
|
|
} while (__page); \
|
|
} while (0)
|
|
|
|
#define CL_PAGE_INVOID_REVERSE(_env, _page, _op, _proto, ...) \
|
|
do { \
|
|
const struct lu_env *__env = (_env); \
|
|
struct cl_page *__page = (_page); \
|
|
const struct cl_page_slice *__scan; \
|
|
ptrdiff_t __op = (_op); \
|
|
void (*__method)_proto; \
|
|
\
|
|
/* get to the bottom page. */ \
|
|
while (__page->cp_child) \
|
|
__page = __page->cp_child; \
|
|
do { \
|
|
list_for_each_entry_reverse(__scan, &__page->cp_layers, \
|
|
cpl_linkage) { \
|
|
__method = *(void **)((char *)__scan->cpl_ops + \
|
|
__op); \
|
|
if (__method) \
|
|
(*__method)(__env, __scan, \
|
|
## __VA_ARGS__); \
|
|
} \
|
|
__page = __page->cp_parent; \
|
|
} while (__page); \
|
|
} while (0)
|
|
|
|
static int cl_page_invoke(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *page, ptrdiff_t op)
|
|
|
|
{
|
|
PINVRNT(env, page, cl_object_same(page->cp_obj, io->ci_obj));
|
|
return CL_PAGE_INVOKE(env, page, op,
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, struct cl_io *),
|
|
io);
|
|
}
|
|
|
|
static void cl_page_invoid(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *page, ptrdiff_t op)
|
|
|
|
{
|
|
PINVRNT(env, page, cl_object_same(page->cp_obj, io->ci_obj));
|
|
CL_PAGE_INVOID(env, page, op,
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, struct cl_io *), io);
|
|
}
|
|
|
|
static void cl_page_owner_clear(struct cl_page *page)
|
|
{
|
|
for (page = cl_page_top(page); page; page = page->cp_child) {
|
|
if (page->cp_owner) {
|
|
LASSERT(page->cp_owner->ci_owned_nr > 0);
|
|
page->cp_owner->ci_owned_nr--;
|
|
page->cp_owner = NULL;
|
|
page->cp_task = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void cl_page_owner_set(struct cl_page *page)
|
|
{
|
|
for (page = cl_page_top(page); page; page = page->cp_child)
|
|
page->cp_owner->ci_owned_nr++;
|
|
}
|
|
|
|
void cl_page_disown0(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
enum cl_page_state state;
|
|
|
|
state = pg->cp_state;
|
|
PINVRNT(env, pg, state == CPS_OWNED || state == CPS_FREEING);
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
cl_page_owner_clear(pg);
|
|
|
|
if (state == CPS_OWNED)
|
|
cl_page_state_set(env, pg, CPS_CACHED);
|
|
/*
|
|
* Completion call-backs are executed in the bottom-up order, so that
|
|
* uppermost layer (llite), responsible for VFS/VM interaction runs
|
|
* last and can release locks safely.
|
|
*/
|
|
CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(cpo_disown),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, struct cl_io *),
|
|
io);
|
|
}
|
|
|
|
/**
|
|
* returns true, iff page is owned by the given io.
|
|
*/
|
|
int cl_page_is_owned(const struct cl_page *pg, const struct cl_io *io)
|
|
{
|
|
LINVRNT(cl_object_same(pg->cp_obj, io->ci_obj));
|
|
return pg->cp_state == CPS_OWNED && pg->cp_owner == io;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_is_owned);
|
|
|
|
/**
|
|
* Try to own a page by IO.
|
|
*
|
|
* Waits until page is in cl_page_state::CPS_CACHED state, and then switch it
|
|
* into cl_page_state::CPS_OWNED state.
|
|
*
|
|
* \pre !cl_page_is_owned(pg, io)
|
|
* \post result == 0 iff cl_page_is_owned(pg, io)
|
|
*
|
|
* \retval 0 success
|
|
*
|
|
* \retval -ve failure, e.g., page was destroyed (and landed in
|
|
* cl_page_state::CPS_FREEING instead of cl_page_state::CPS_CACHED).
|
|
* or, page was owned by another thread, or in IO.
|
|
*
|
|
* \see cl_page_disown()
|
|
* \see cl_page_operations::cpo_own()
|
|
* \see cl_page_own_try()
|
|
* \see cl_page_own
|
|
*/
|
|
static int cl_page_own0(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *pg, int nonblock)
|
|
{
|
|
int result;
|
|
|
|
PINVRNT(env, pg, !cl_page_is_owned(pg, io));
|
|
|
|
pg = cl_page_top(pg);
|
|
io = cl_io_top(io);
|
|
|
|
if (pg->cp_state == CPS_FREEING) {
|
|
result = -ENOENT;
|
|
} else {
|
|
result = CL_PAGE_INVOKE(env, pg, CL_PAGE_OP(cpo_own),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *,
|
|
struct cl_io *, int),
|
|
io, nonblock);
|
|
if (result == 0) {
|
|
PASSERT(env, pg, !pg->cp_owner);
|
|
PASSERT(env, pg, !pg->cp_req);
|
|
pg->cp_owner = io;
|
|
pg->cp_task = current;
|
|
cl_page_owner_set(pg);
|
|
if (pg->cp_state != CPS_FREEING) {
|
|
cl_page_state_set(env, pg, CPS_OWNED);
|
|
} else {
|
|
cl_page_disown0(env, io, pg);
|
|
result = -ENOENT;
|
|
}
|
|
}
|
|
}
|
|
PINVRNT(env, pg, ergo(result == 0, cl_page_invariant(pg)));
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* Own a page, might be blocked.
|
|
*
|
|
* \see cl_page_own0()
|
|
*/
|
|
int cl_page_own(const struct lu_env *env, struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
return cl_page_own0(env, io, pg, 0);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_own);
|
|
|
|
/**
|
|
* Nonblock version of cl_page_own().
|
|
*
|
|
* \see cl_page_own0()
|
|
*/
|
|
int cl_page_own_try(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *pg)
|
|
{
|
|
return cl_page_own0(env, io, pg, 1);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_own_try);
|
|
|
|
/**
|
|
* Assume page ownership.
|
|
*
|
|
* Called when page is already locked by the hosting VM.
|
|
*
|
|
* \pre !cl_page_is_owned(pg, io)
|
|
* \post cl_page_is_owned(pg, io)
|
|
*
|
|
* \see cl_page_operations::cpo_assume()
|
|
*/
|
|
void cl_page_assume(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_object_same(pg->cp_obj, io->ci_obj));
|
|
|
|
pg = cl_page_top(pg);
|
|
io = cl_io_top(io);
|
|
|
|
cl_page_invoid(env, io, pg, CL_PAGE_OP(cpo_assume));
|
|
PASSERT(env, pg, !pg->cp_owner);
|
|
pg->cp_owner = io;
|
|
pg->cp_task = current;
|
|
cl_page_owner_set(pg);
|
|
cl_page_state_set(env, pg, CPS_OWNED);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_assume);
|
|
|
|
/**
|
|
* Releases page ownership without unlocking the page.
|
|
*
|
|
* Moves page into cl_page_state::CPS_CACHED without releasing a lock on the
|
|
* underlying VM page (as VM is supposed to do this itself).
|
|
*
|
|
* \pre cl_page_is_owned(pg, io)
|
|
* \post !cl_page_is_owned(pg, io)
|
|
*
|
|
* \see cl_page_assume()
|
|
*/
|
|
void cl_page_unassume(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
pg = cl_page_top(pg);
|
|
io = cl_io_top(io);
|
|
cl_page_owner_clear(pg);
|
|
cl_page_state_set(env, pg, CPS_CACHED);
|
|
CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(cpo_unassume),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, struct cl_io *),
|
|
io);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_unassume);
|
|
|
|
/**
|
|
* Releases page ownership.
|
|
*
|
|
* Moves page into cl_page_state::CPS_CACHED.
|
|
*
|
|
* \pre cl_page_is_owned(pg, io)
|
|
* \post !cl_page_is_owned(pg, io)
|
|
*
|
|
* \see cl_page_own()
|
|
* \see cl_page_operations::cpo_disown()
|
|
*/
|
|
void cl_page_disown(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
|
|
pg = cl_page_top(pg);
|
|
io = cl_io_top(io);
|
|
cl_page_disown0(env, io, pg);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_disown);
|
|
|
|
/**
|
|
* Called when page is to be removed from the object, e.g., as a result of
|
|
* truncate.
|
|
*
|
|
* Calls cl_page_operations::cpo_discard() top-to-bottom.
|
|
*
|
|
* \pre cl_page_is_owned(pg, io)
|
|
*
|
|
* \see cl_page_operations::cpo_discard()
|
|
*/
|
|
void cl_page_discard(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
cl_page_invoid(env, io, pg, CL_PAGE_OP(cpo_discard));
|
|
}
|
|
EXPORT_SYMBOL(cl_page_discard);
|
|
|
|
/**
|
|
* Version of cl_page_delete() that can be called for not fully constructed
|
|
* pages, e.g,. in a error handling cl_page_find()->cl_page_delete0()
|
|
* path. Doesn't check page invariant.
|
|
*/
|
|
static void cl_page_delete0(const struct lu_env *env, struct cl_page *pg,
|
|
int radix)
|
|
{
|
|
struct cl_page *tmp = pg;
|
|
|
|
PASSERT(env, pg, pg == cl_page_top(pg));
|
|
PASSERT(env, pg, pg->cp_state != CPS_FREEING);
|
|
|
|
/*
|
|
* Severe all ways to obtain new pointers to @pg.
|
|
*/
|
|
cl_page_owner_clear(pg);
|
|
|
|
/*
|
|
* unexport the page firstly before freeing it so that
|
|
* the page content is considered to be invalid.
|
|
* We have to do this because a CPS_FREEING cl_page may
|
|
* be NOT under the protection of a cl_lock.
|
|
* Afterwards, if this page is found by other threads, then this
|
|
* page will be forced to reread.
|
|
*/
|
|
cl_page_export(env, pg, 0);
|
|
cl_page_state_set0(env, pg, CPS_FREEING);
|
|
|
|
CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_delete),
|
|
(const struct lu_env *, const struct cl_page_slice *));
|
|
|
|
if (tmp->cp_type == CPT_CACHEABLE) {
|
|
if (!radix)
|
|
/* !radix means that @pg is not yet in the radix tree,
|
|
* skip removing it.
|
|
*/
|
|
tmp = pg->cp_child;
|
|
for (; tmp; tmp = tmp->cp_child) {
|
|
void *value;
|
|
struct cl_object_header *hdr;
|
|
|
|
hdr = cl_object_header(tmp->cp_obj);
|
|
spin_lock(&hdr->coh_page_guard);
|
|
value = radix_tree_delete(&hdr->coh_tree,
|
|
tmp->cp_index);
|
|
PASSERT(env, tmp, value == tmp);
|
|
PASSERT(env, tmp, hdr->coh_pages > 0);
|
|
hdr->coh_pages--;
|
|
spin_unlock(&hdr->coh_page_guard);
|
|
cl_page_put(env, tmp);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Called when a decision is made to throw page out of memory.
|
|
*
|
|
* Notifies all layers about page destruction by calling
|
|
* cl_page_operations::cpo_delete() method top-to-bottom.
|
|
*
|
|
* Moves page into cl_page_state::CPS_FREEING state (this is the only place
|
|
* where transition to this state happens).
|
|
*
|
|
* Eliminates all venues through which new references to the page can be
|
|
* obtained:
|
|
*
|
|
* - removes page from the radix trees,
|
|
*
|
|
* - breaks linkage from VM page to cl_page.
|
|
*
|
|
* Once page reaches cl_page_state::CPS_FREEING, all remaining references will
|
|
* drain after some time, at which point page will be recycled.
|
|
*
|
|
* \pre pg == cl_page_top(pg)
|
|
* \pre VM page is locked
|
|
* \post pg->cp_state == CPS_FREEING
|
|
*
|
|
* \see cl_page_operations::cpo_delete()
|
|
*/
|
|
void cl_page_delete(const struct lu_env *env, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
cl_page_delete0(env, pg, 1);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_delete);
|
|
|
|
/**
|
|
* Unmaps page from user virtual memory.
|
|
*
|
|
* Calls cl_page_operations::cpo_unmap() through all layers top-to-bottom. The
|
|
* layer responsible for VM interaction has to unmap page from user space
|
|
* virtual memory.
|
|
*
|
|
* \see cl_page_operations::cpo_unmap()
|
|
*/
|
|
int cl_page_unmap(const struct lu_env *env,
|
|
struct cl_io *io, struct cl_page *pg)
|
|
{
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
return cl_page_invoke(env, io, pg, CL_PAGE_OP(cpo_unmap));
|
|
}
|
|
EXPORT_SYMBOL(cl_page_unmap);
|
|
|
|
/**
|
|
* Marks page up-to-date.
|
|
*
|
|
* Call cl_page_operations::cpo_export() through all layers top-to-bottom. The
|
|
* layer responsible for VM interaction has to mark/clear page as up-to-date
|
|
* by the \a uptodate argument.
|
|
*
|
|
* \see cl_page_operations::cpo_export()
|
|
*/
|
|
void cl_page_export(const struct lu_env *env, struct cl_page *pg, int uptodate)
|
|
{
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_export),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, int), uptodate);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_export);
|
|
|
|
/**
|
|
* Returns true, iff \a pg is VM locked in a suitable sense by the calling
|
|
* thread.
|
|
*/
|
|
int cl_page_is_vmlocked(const struct lu_env *env, const struct cl_page *pg)
|
|
{
|
|
int result;
|
|
const struct cl_page_slice *slice;
|
|
|
|
pg = cl_page_top_trusted((struct cl_page *)pg);
|
|
slice = container_of(pg->cp_layers.next,
|
|
const struct cl_page_slice, cpl_linkage);
|
|
PASSERT(env, pg, slice->cpl_ops->cpo_is_vmlocked);
|
|
/*
|
|
* Call ->cpo_is_vmlocked() directly instead of going through
|
|
* CL_PAGE_INVOKE(), because cl_page_is_vmlocked() is used by
|
|
* cl_page_invariant().
|
|
*/
|
|
result = slice->cpl_ops->cpo_is_vmlocked(env, slice);
|
|
PASSERT(env, pg, result == -EBUSY || result == -ENODATA);
|
|
return result == -EBUSY;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_is_vmlocked);
|
|
|
|
static enum cl_page_state cl_req_type_state(enum cl_req_type crt)
|
|
{
|
|
return crt == CRT_WRITE ? CPS_PAGEOUT : CPS_PAGEIN;
|
|
}
|
|
|
|
static void cl_page_io_start(const struct lu_env *env,
|
|
struct cl_page *pg, enum cl_req_type crt)
|
|
{
|
|
/*
|
|
* Page is queued for IO, change its state.
|
|
*/
|
|
cl_page_owner_clear(pg);
|
|
cl_page_state_set(env, pg, cl_req_type_state(crt));
|
|
}
|
|
|
|
/**
|
|
* Prepares page for immediate transfer. cl_page_operations::cpo_prep() is
|
|
* called top-to-bottom. Every layer either agrees to submit this page (by
|
|
* returning 0), or requests to omit this page (by returning -EALREADY). Layer
|
|
* handling interactions with the VM also has to inform VM that page is under
|
|
* transfer now.
|
|
*/
|
|
int cl_page_prep(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *pg, enum cl_req_type crt)
|
|
{
|
|
int result;
|
|
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
PINVRNT(env, pg, crt < CRT_NR);
|
|
|
|
/*
|
|
* XXX this has to be called bottom-to-top, so that llite can set up
|
|
* PG_writeback without risking other layers deciding to skip this
|
|
* page.
|
|
*/
|
|
if (crt >= CRT_NR)
|
|
return -EINVAL;
|
|
result = cl_page_invoke(env, io, pg, CL_PAGE_OP(io[crt].cpo_prep));
|
|
if (result == 0)
|
|
cl_page_io_start(env, pg, crt);
|
|
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_prep);
|
|
|
|
/**
|
|
* Notify layers about transfer completion.
|
|
*
|
|
* Invoked by transfer sub-system (which is a part of osc) to notify layers
|
|
* that a transfer, of which this page is a part of has completed.
|
|
*
|
|
* Completion call-backs are executed in the bottom-up order, so that
|
|
* uppermost layer (llite), responsible for the VFS/VM interaction runs last
|
|
* and can release locks safely.
|
|
*
|
|
* \pre pg->cp_state == CPS_PAGEIN || pg->cp_state == CPS_PAGEOUT
|
|
* \post pg->cp_state == CPS_CACHED
|
|
*
|
|
* \see cl_page_operations::cpo_completion()
|
|
*/
|
|
void cl_page_completion(const struct lu_env *env,
|
|
struct cl_page *pg, enum cl_req_type crt, int ioret)
|
|
{
|
|
struct cl_sync_io *anchor = pg->cp_sync_io;
|
|
|
|
PASSERT(env, pg, crt < CRT_NR);
|
|
/* cl_page::cp_req already cleared by the caller (osc_completion()) */
|
|
PASSERT(env, pg, !pg->cp_req);
|
|
PASSERT(env, pg, pg->cp_state == cl_req_type_state(crt));
|
|
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, ioret);
|
|
if (crt == CRT_READ && ioret == 0) {
|
|
PASSERT(env, pg, !(pg->cp_flags & CPF_READ_COMPLETED));
|
|
pg->cp_flags |= CPF_READ_COMPLETED;
|
|
}
|
|
|
|
cl_page_state_set(env, pg, CPS_CACHED);
|
|
if (crt >= CRT_NR)
|
|
return;
|
|
CL_PAGE_INVOID_REVERSE(env, pg, CL_PAGE_OP(io[crt].cpo_completion),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, int), ioret);
|
|
if (anchor) {
|
|
LASSERT(cl_page_is_vmlocked(env, pg));
|
|
LASSERT(pg->cp_sync_io == anchor);
|
|
pg->cp_sync_io = NULL;
|
|
}
|
|
/*
|
|
* 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, pg);
|
|
|
|
if (anchor)
|
|
cl_sync_io_note(anchor, ioret);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_completion);
|
|
|
|
/**
|
|
* Notify layers that transfer formation engine decided to yank this page from
|
|
* the cache and to make it a part of a transfer.
|
|
*
|
|
* \pre pg->cp_state == CPS_CACHED
|
|
* \post pg->cp_state == CPS_PAGEIN || pg->cp_state == CPS_PAGEOUT
|
|
*
|
|
* \see cl_page_operations::cpo_make_ready()
|
|
*/
|
|
int cl_page_make_ready(const struct lu_env *env, struct cl_page *pg,
|
|
enum cl_req_type crt)
|
|
{
|
|
int result;
|
|
|
|
PINVRNT(env, pg, crt < CRT_NR);
|
|
|
|
if (crt >= CRT_NR)
|
|
return -EINVAL;
|
|
result = CL_PAGE_INVOKE(env, pg, CL_PAGE_OP(io[crt].cpo_make_ready),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *));
|
|
if (result == 0) {
|
|
PASSERT(env, pg, pg->cp_state == CPS_CACHED);
|
|
cl_page_io_start(env, pg, crt);
|
|
}
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_make_ready);
|
|
|
|
/**
|
|
* Notify layers that high level io decided to place this page into a cache
|
|
* for future transfer.
|
|
*
|
|
* The layer implementing transfer engine (osc) has to register this page in
|
|
* its queues.
|
|
*
|
|
* \pre cl_page_is_owned(pg, io)
|
|
* \post cl_page_is_owned(pg, io)
|
|
*
|
|
* \see cl_page_operations::cpo_cache_add()
|
|
*/
|
|
int cl_page_cache_add(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *pg, enum cl_req_type crt)
|
|
{
|
|
const struct cl_page_slice *scan;
|
|
int result = 0;
|
|
|
|
PINVRNT(env, pg, crt < CRT_NR);
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
if (crt >= CRT_NR)
|
|
return -EINVAL;
|
|
|
|
list_for_each_entry(scan, &pg->cp_layers, cpl_linkage) {
|
|
if (!scan->cpl_ops->io[crt].cpo_cache_add)
|
|
continue;
|
|
|
|
result = scan->cpl_ops->io[crt].cpo_cache_add(env, scan, io);
|
|
if (result != 0)
|
|
break;
|
|
}
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", crt, result);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_cache_add);
|
|
|
|
/**
|
|
* Called if a pge is being written back by kernel's intention.
|
|
*
|
|
* \pre cl_page_is_owned(pg, io)
|
|
* \post ergo(result == 0, pg->cp_state == CPS_PAGEOUT)
|
|
*
|
|
* \see cl_page_operations::cpo_flush()
|
|
*/
|
|
int cl_page_flush(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *pg)
|
|
{
|
|
int result;
|
|
|
|
PINVRNT(env, pg, cl_page_is_owned(pg, io));
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
result = cl_page_invoke(env, io, pg, CL_PAGE_OP(cpo_flush));
|
|
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d\n", result);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_flush);
|
|
|
|
/**
|
|
* Checks whether page is protected by any extent lock is at least required
|
|
* mode.
|
|
*
|
|
* \return the same as in cl_page_operations::cpo_is_under_lock() method.
|
|
* \see cl_page_operations::cpo_is_under_lock()
|
|
*/
|
|
int cl_page_is_under_lock(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *page)
|
|
{
|
|
int rc;
|
|
|
|
PINVRNT(env, page, cl_page_invariant(page));
|
|
|
|
rc = CL_PAGE_INVOKE(env, page, CL_PAGE_OP(cpo_is_under_lock),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, struct cl_io *),
|
|
io);
|
|
PASSERT(env, page, rc != 0);
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_is_under_lock);
|
|
|
|
static int page_prune_cb(const struct lu_env *env, struct cl_io *io,
|
|
struct cl_page *page, void *cbdata)
|
|
{
|
|
cl_page_own(env, io, page);
|
|
cl_page_unmap(env, io, page);
|
|
cl_page_discard(env, io, page);
|
|
cl_page_disown(env, io, page);
|
|
return CLP_GANG_OKAY;
|
|
}
|
|
|
|
/**
|
|
* Purges all cached pages belonging to the object \a obj.
|
|
*/
|
|
int cl_pages_prune(const struct lu_env *env, struct cl_object *clobj)
|
|
{
|
|
struct cl_thread_info *info;
|
|
struct cl_object *obj = cl_object_top(clobj);
|
|
struct cl_io *io;
|
|
int result;
|
|
|
|
info = cl_env_info(env);
|
|
io = &info->clt_io;
|
|
|
|
/*
|
|
* initialize the io. This is ugly since we never do IO in this
|
|
* function, we just make cl_page_list functions happy. -jay
|
|
*/
|
|
io->ci_obj = obj;
|
|
io->ci_ignore_layout = 1;
|
|
result = cl_io_init(env, io, CIT_MISC, obj);
|
|
if (result != 0) {
|
|
cl_io_fini(env, io);
|
|
return io->ci_result;
|
|
}
|
|
|
|
do {
|
|
result = cl_page_gang_lookup(env, obj, io, 0, CL_PAGE_EOF,
|
|
page_prune_cb, NULL);
|
|
if (result == CLP_GANG_RESCHED)
|
|
cond_resched();
|
|
} while (result != CLP_GANG_OKAY);
|
|
|
|
cl_io_fini(env, io);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL(cl_pages_prune);
|
|
|
|
/**
|
|
* Tells transfer engine that only part of a page is to be transmitted.
|
|
*
|
|
* \see cl_page_operations::cpo_clip()
|
|
*/
|
|
void cl_page_clip(const struct lu_env *env, struct cl_page *pg,
|
|
int from, int to)
|
|
{
|
|
PINVRNT(env, pg, cl_page_invariant(pg));
|
|
|
|
CL_PAGE_HEADER(D_TRACE, env, pg, "%d %d\n", from, to);
|
|
CL_PAGE_INVOID(env, pg, CL_PAGE_OP(cpo_clip),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *, int, int),
|
|
from, to);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_clip);
|
|
|
|
/**
|
|
* Prints human readable representation of \a pg to the \a f.
|
|
*/
|
|
void cl_page_header_print(const struct lu_env *env, void *cookie,
|
|
lu_printer_t printer, const struct cl_page *pg)
|
|
{
|
|
(*printer)(env, cookie,
|
|
"page@%p[%d %p:%lu ^%p_%p %d %d %d %p %p %#x]\n",
|
|
pg, atomic_read(&pg->cp_ref), pg->cp_obj,
|
|
pg->cp_index, pg->cp_parent, pg->cp_child,
|
|
pg->cp_state, pg->cp_error, pg->cp_type,
|
|
pg->cp_owner, pg->cp_req, pg->cp_flags);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_header_print);
|
|
|
|
/**
|
|
* Prints human readable representation of \a pg to the \a f.
|
|
*/
|
|
void cl_page_print(const struct lu_env *env, void *cookie,
|
|
lu_printer_t printer, const struct cl_page *pg)
|
|
{
|
|
struct cl_page *scan;
|
|
|
|
for (scan = cl_page_top((struct cl_page *)pg); scan;
|
|
scan = scan->cp_child)
|
|
cl_page_header_print(env, cookie, printer, scan);
|
|
CL_PAGE_INVOKE(env, (struct cl_page *)pg, CL_PAGE_OP(cpo_print),
|
|
(const struct lu_env *env,
|
|
const struct cl_page_slice *slice,
|
|
void *cookie, lu_printer_t p), cookie, printer);
|
|
(*printer)(env, cookie, "end page@%p\n", pg);
|
|
}
|
|
EXPORT_SYMBOL(cl_page_print);
|
|
|
|
/**
|
|
* Cancel a page which is still in a transfer.
|
|
*/
|
|
int cl_page_cancel(const struct lu_env *env, struct cl_page *page)
|
|
{
|
|
return CL_PAGE_INVOKE(env, page, CL_PAGE_OP(cpo_cancel),
|
|
(const struct lu_env *,
|
|
const struct cl_page_slice *));
|
|
}
|
|
EXPORT_SYMBOL(cl_page_cancel);
|
|
|
|
/**
|
|
* Converts a byte offset within object \a obj into a page index.
|
|
*/
|
|
loff_t cl_offset(const struct cl_object *obj, pgoff_t idx)
|
|
{
|
|
/*
|
|
* XXX for now.
|
|
*/
|
|
return (loff_t)idx << PAGE_SHIFT;
|
|
}
|
|
EXPORT_SYMBOL(cl_offset);
|
|
|
|
/**
|
|
* Converts a page index into a byte offset within object \a obj.
|
|
*/
|
|
pgoff_t cl_index(const struct cl_object *obj, loff_t offset)
|
|
{
|
|
/*
|
|
* XXX for now.
|
|
*/
|
|
return offset >> PAGE_SHIFT;
|
|
}
|
|
EXPORT_SYMBOL(cl_index);
|
|
|
|
int cl_page_size(const struct cl_object *obj)
|
|
{
|
|
return 1 << PAGE_SHIFT;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_size);
|
|
|
|
/**
|
|
* Adds page slice to the compound page.
|
|
*
|
|
* This is called by cl_object_operations::coo_page_init() methods to add a
|
|
* per-layer state to the page. New state is added at the end of
|
|
* cl_page::cp_layers list, that is, it is at the bottom of the stack.
|
|
*
|
|
* \see cl_lock_slice_add(), cl_req_slice_add(), cl_io_slice_add()
|
|
*/
|
|
void cl_page_slice_add(struct cl_page *page, struct cl_page_slice *slice,
|
|
struct cl_object *obj,
|
|
const struct cl_page_operations *ops)
|
|
{
|
|
list_add_tail(&slice->cpl_linkage, &page->cp_layers);
|
|
slice->cpl_obj = obj;
|
|
slice->cpl_ops = ops;
|
|
slice->cpl_page = page;
|
|
}
|
|
EXPORT_SYMBOL(cl_page_slice_add);
|
|
|
|
int cl_page_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
void cl_page_fini(void)
|
|
{
|
|
}
|