/* * 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.gnu.org/licenses/gpl-2.0.html * * GPL HEADER END */ /* * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. * Use is subject to license terms. * * Copyright (c) 2011, 2017, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ * * Implementation of cl_page for VVP layer. * * Author: Nikita Danilov * Author: Jinshan Xiong */ #define DEBUG_SUBSYSTEM S_LLITE #include #include #include #include #include #include #include #include "llite_internal.h" #include "vvp_internal.h" /***************************************************************************** * * Page operations. * */ static void vvp_page_discard(const struct lu_env *env, const struct cl_page_slice *slice, struct cl_io *unused) { struct cl_page *cp = slice->cpl_page; struct page *vmpage = cp->cp_vmpage; if (cp->cp_defer_uptodate && !cp->cp_ra_used && vmpage->mapping != NULL) ll_ra_stats_inc(vmpage->mapping->host, RA_STAT_DISCARDED); } static void vvp_page_delete(const struct lu_env *env, const struct cl_page_slice *slice) { struct cl_page *cp = slice->cpl_page; if (cp->cp_type == CPT_CACHEABLE) { struct page *vmpage = cp->cp_vmpage; struct inode *inode = vmpage->mapping->host; LASSERT(PageLocked(vmpage)); LASSERT((struct cl_page *)vmpage->private == cp); /* Drop the reference count held in vvp_page_init */ refcount_dec(&cp->cp_ref); ClearPagePrivate(vmpage); vmpage->private = 0; /* clearpageuptodate prevents the page being read by the * kernel after it has been deleted from Lustre, which avoids * potential stale data reads. The seqlock allows us to see * that a page was potentially deleted and catch the resulting * SIGBUS - see ll_filemap_fault() (LU-16160) */ if (PageUptodate(vmpage)) { write_seqlock(&ll_i2info(inode)->lli_page_inv_lock); ClearPageUptodate(vmpage); write_sequnlock(&ll_i2info(inode)->lli_page_inv_lock); } /* The reference from vmpage to cl_page is removed, * but the reference back is still here. It is removed * later in cl_page_free(). */ } } /** * Handles page transfer errors at VM level. * * This takes inode as a separate argument, because inode on which error is to * be set can be different from \a vmpage inode in case of direct-io. */ static void vvp_vmpage_error(struct inode *inode, struct page *vmpage, int ioret) { struct vvp_object *obj = cl_inode2vvp(inode); if (ioret == 0) { ClearPageError(vmpage); obj->vob_discard_page_warned = 0; } else { SetPageError(vmpage); if (ioret != -ENOSPC && CFS_FAIL_CHECK(OBD_FAIL_LLITE_PANIC_ON_ESTALE)) LBUG(); mapping_set_error(inode->i_mapping, ioret); if ((ioret == -ESHUTDOWN || ioret == -EINTR || ioret == -EIO) && obj->vob_discard_page_warned == 0) { obj->vob_discard_page_warned = 1; ll_dirty_page_discard_warn(inode, ioret); } } } static void vvp_page_completion_read(const struct lu_env *env, const struct cl_page_slice *slice, int ioret) { struct cl_page *cp = slice->cpl_page; struct page *vmpage = cp->cp_vmpage; struct inode *inode = vvp_object_inode(cp->cp_obj); ENTRY; LASSERT(PageLocked(vmpage)); CL_PAGE_HEADER(D_PAGE, env, cp, "completing READ with %d\n", ioret); if (cp->cp_defer_uptodate) ll_ra_count_put(ll_i2sbi(inode), 1); if (ioret == 0) { /** * cp_defer_uptodate is used for readahead page, and the * vmpage Uptodate bit is deferred to set in ll_readpage/ * ll_io_read_page. */ if (!cp->cp_defer_uptodate) SetPageUptodate(vmpage); } else if (cp->cp_defer_uptodate) { cp->cp_defer_uptodate = 0; if (ioret == -EAGAIN) { /* mirror read failed, it needs to destroy the page * because subpage would be from wrong osc when trying * to read from a new mirror */ generic_error_remove_folio(vmpage->mapping, page_folio(vmpage)); } } if (cp->cp_sync_io == NULL) unlock_page(vmpage); EXIT; } static void vvp_page_completion_write(const struct lu_env *env, const struct cl_page_slice *slice, int ioret) { struct cl_page *cp = slice->cpl_page; struct page *vmpage = cp->cp_vmpage; ENTRY; CL_PAGE_HEADER(D_PAGE, env, cp, "completing WRITE with %d\n", ioret); if (cp->cp_sync_io != NULL) { LASSERT(PageLocked(vmpage)); LASSERT(!PageWriteback(vmpage)); } else { LASSERT(PageWriteback(vmpage)); /* * Only mark the page error only when it's an async write * because applications won't wait for IO to finish. */ vvp_vmpage_error(vvp_object_inode(cp->cp_obj), vmpage, ioret); end_page_writeback(vmpage); } EXIT; } static const struct cl_page_operations vvp_page_ops = { .cpo_delete = vvp_page_delete, .cpo_discard = vvp_page_discard, .io = { [CRT_READ] = { .cpo_completion = vvp_page_completion_read, }, [CRT_WRITE] = { .cpo_completion = vvp_page_completion_write, }, }, }; static const struct cl_page_operations vvp_transient_page_ops = { }; int vvp_page_init(const struct lu_env *env, struct cl_object *obj, struct cl_page *page, pgoff_t index) { struct cl_page_slice *cpl = cl_object_page_slice(obj, page); struct page *vmpage = page->cp_vmpage; CLOBINVRNT(env, obj, vvp_object_invariant(obj)); if (page->cp_type == CPT_TRANSIENT) { /* DIO pages are referenced by userspace, we don't need to take * a reference on them. (contrast with get_page() call above) */ cl_page_slice_add(page, cpl, obj, &vvp_transient_page_ops); } else { get_page(vmpage); /* in cache, decref in cl_page_delete() */ refcount_inc(&page->cp_ref); SetPagePrivate(vmpage); vmpage->private = (unsigned long)page; cl_page_slice_add(page, cpl, obj, &vvp_page_ops); } return 0; }