1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 only,
10 * as published by the Free Software Foundation.
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License version 2 for more details (a copy is included
16 * in the LICENSE file that accompanied this code).
18 * You should have received a copy of the GNU General Public License
19 * version 2 along with this program; If not, see
20 * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
29 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
30 * Use is subject to license terms.
32 * Copyright (c) 2011, Whamcloud, Inc.
35 * This file is part of Lustre, http://www.lustre.org/
36 * Lustre is a trademark of Sun Microsystems, Inc.
38 * Implementation of cl_page for VVP layer.
40 * Author: Nikita Danilov <nikita.danilov@sun.com>
43 #define DEBUG_SUBSYSTEM S_LLITE
46 # error This file is kernel only.
50 #include <lustre_lite.h>
52 #include "vvp_internal.h"
54 /*****************************************************************************
60 static void vvp_page_fini_common(struct ccc_page *cp)
62 cfs_page_t *vmpage = cp->cpg_page;
64 LASSERT(vmpage != NULL);
65 page_cache_release(vmpage);
66 OBD_SLAB_FREE_PTR(cp, vvp_page_kmem);
69 static void vvp_page_fini(const struct lu_env *env,
70 struct cl_page_slice *slice)
72 struct ccc_page *cp = cl2ccc_page(slice);
73 cfs_page_t *vmpage = cp->cpg_page;
76 * vmpage->private was already cleared when page was moved into
79 LASSERT((struct cl_page *)vmpage->private != slice->cpl_page);
80 vvp_page_fini_common(cp);
83 static int vvp_page_own(const struct lu_env *env,
84 const struct cl_page_slice *slice, struct cl_io *io,
87 struct ccc_page *vpg = cl2ccc_page(slice);
88 cfs_page_t *vmpage = vpg->cpg_page;
90 LASSERT(vmpage != NULL);
92 if (TestSetPageLocked(vmpage))
95 if (unlikely(PageWriteback(vmpage))) {
104 wait_on_page_writeback(vmpage);
108 static void vvp_page_assume(const struct lu_env *env,
109 const struct cl_page_slice *slice,
110 struct cl_io *unused)
112 cfs_page_t *vmpage = cl2vm_page(slice);
114 LASSERT(vmpage != NULL);
115 LASSERT(PageLocked(vmpage));
116 wait_on_page_writeback(vmpage);
119 static void vvp_page_unassume(const struct lu_env *env,
120 const struct cl_page_slice *slice,
121 struct cl_io *unused)
123 cfs_page_t *vmpage = cl2vm_page(slice);
125 LASSERT(vmpage != NULL);
126 LASSERT(PageLocked(vmpage));
129 static void vvp_page_disown(const struct lu_env *env,
130 const struct cl_page_slice *slice, struct cl_io *io)
132 cfs_page_t *vmpage = cl2vm_page(slice);
134 LASSERT(vmpage != NULL);
135 LASSERT(PageLocked(vmpage));
137 unlock_page(cl2vm_page(slice));
140 static void vvp_page_discard(const struct lu_env *env,
141 const struct cl_page_slice *slice,
142 struct cl_io *unused)
144 cfs_page_t *vmpage = cl2vm_page(slice);
145 struct address_space *mapping = vmpage->mapping;
146 struct ccc_page *cpg = cl2ccc_page(slice);
148 LASSERT(vmpage != NULL);
149 LASSERT(PageLocked(vmpage));
151 if (cpg->cpg_defer_uptodate && !cpg->cpg_ra_used)
152 ll_ra_stats_inc(mapping, RA_STAT_DISCARDED);
155 * truncate_complete_page() calls
156 * a_ops->invalidatepage()->cl_page_delete()->vvp_page_delete().
158 truncate_complete_page(mapping, vmpage);
161 static int vvp_page_unmap(const struct lu_env *env,
162 const struct cl_page_slice *slice,
163 struct cl_io *unused)
165 cfs_page_t *vmpage = cl2vm_page(slice);
166 __u64 offset = vmpage->index << CFS_PAGE_SHIFT;
168 LASSERT(vmpage != NULL);
169 LASSERT(PageLocked(vmpage));
171 * XXX is it safe to call this with the page lock held?
173 ll_teardown_mmaps(vmpage->mapping, offset, offset + CFS_PAGE_SIZE);
177 static void vvp_page_delete(const struct lu_env *env,
178 const struct cl_page_slice *slice)
180 cfs_page_t *vmpage = cl2vm_page(slice);
181 struct inode *inode = vmpage->mapping->host;
182 struct cl_object *obj = slice->cpl_obj;
184 LASSERT(PageLocked(vmpage));
185 LASSERT((struct cl_page *)vmpage->private == slice->cpl_page);
186 LASSERT(inode == ccc_object_inode(obj));
188 vvp_write_complete(cl2ccc(obj), cl2ccc_page(slice));
189 ClearPagePrivate(vmpage);
192 * Reference from vmpage to cl_page is removed, but the reference back
193 * is still here. It is removed later in vvp_page_fini().
197 static void vvp_page_export(const struct lu_env *env,
198 const struct cl_page_slice *slice,
201 cfs_page_t *vmpage = cl2vm_page(slice);
203 LASSERT(vmpage != NULL);
204 LASSERT(PageLocked(vmpage));
206 SetPageUptodate(vmpage);
208 ClearPageUptodate(vmpage);
211 static int vvp_page_is_vmlocked(const struct lu_env *env,
212 const struct cl_page_slice *slice)
214 return PageLocked(cl2vm_page(slice)) ? -EBUSY : -ENODATA;
217 static int vvp_page_prep_read(const struct lu_env *env,
218 const struct cl_page_slice *slice,
219 struct cl_io *unused)
222 /* Skip the page already marked as PG_uptodate. */
223 RETURN(PageUptodate(cl2vm_page(slice)) ? -EALREADY : 0);
226 static int vvp_page_prep_write(const struct lu_env *env,
227 const struct cl_page_slice *slice,
228 struct cl_io *unused)
230 struct cl_page *cp = slice->cpl_page;
231 cfs_page_t *vmpage = cl2vm_page(slice);
234 if (clear_page_dirty_for_io(vmpage)) {
235 set_page_writeback(vmpage);
236 vvp_write_pending(cl2ccc(slice->cpl_obj), cl2ccc_page(slice));
239 /* only turn on writeback for async write. */
240 if (cp->cp_sync_io == NULL)
248 * Handles page transfer errors at VM level.
250 * This takes inode as a separate argument, because inode on which error is to
251 * be set can be different from \a vmpage inode in case of direct-io.
253 static void vvp_vmpage_error(struct inode *inode, cfs_page_t *vmpage, int ioret)
256 ClearPageError(vmpage);
257 else if (ioret != -EINTR) {
258 SetPageError(vmpage);
259 if (ioret == -ENOSPC)
260 set_bit(AS_ENOSPC, &inode->i_mapping->flags);
262 set_bit(AS_EIO, &inode->i_mapping->flags);
266 static void vvp_page_completion_read(const struct lu_env *env,
267 const struct cl_page_slice *slice,
270 struct ccc_page *cp = cl2ccc_page(slice);
271 cfs_page_t *vmpage = cp->cpg_page;
272 struct cl_page *page = cl_page_top(slice->cpl_page);
273 struct inode *inode = ccc_object_inode(page->cp_obj);
276 LASSERT(PageLocked(vmpage));
277 CL_PAGE_HEADER(D_PAGE, env, page, "completing READ with %d\n", ioret);
279 if (cp->cpg_defer_uptodate)
280 ll_ra_count_put(ll_i2sbi(inode), 1);
283 if (!cp->cpg_defer_uptodate)
284 cl_page_export(env, page, 1);
286 cp->cpg_defer_uptodate = 0;
288 if (page->cp_sync_io == NULL)
294 static void vvp_page_completion_write(const struct lu_env *env,
295 const struct cl_page_slice *slice,
298 struct ccc_page *cp = cl2ccc_page(slice);
299 struct cl_page *pg = slice->cpl_page;
300 cfs_page_t *vmpage = cp->cpg_page;
303 LASSERT(ergo(pg->cp_sync_io != NULL, PageLocked(vmpage)));
304 LASSERT(PageWriteback(vmpage));
306 CL_PAGE_HEADER(D_PAGE, env, pg, "completing WRITE with %d\n", ioret);
309 * TODO: Actually it makes sense to add the page into oap pending
310 * list again and so that we don't need to take the page out from
311 * SoM write pending list, if we just meet a recoverable error,
313 * To implement this, we just need to return a non zero value in
314 * ->cpo_completion method. The underlying transfer should be notified
315 * and then re-add the page into pending transfer queue. -jay
318 cp->cpg_write_queued = 0;
319 vvp_write_complete(cl2ccc(slice->cpl_obj), cp);
322 * Only mark the page error only when it's an async write because
323 * applications won't wait for IO to finish.
325 if (pg->cp_sync_io == NULL)
326 vvp_vmpage_error(ccc_object_inode(pg->cp_obj), vmpage, ioret);
328 end_page_writeback(vmpage);
333 * Implements cl_page_operations::cpo_make_ready() method.
335 * This is called to yank a page from the transfer cache and to send it out as
336 * a part of transfer. This function try-locks the page. If try-lock failed,
337 * page is owned by some concurrent IO, and should be skipped (this is bad,
338 * but hopefully rare situation, as it usually results in transfer being
339 * shorter than possible).
341 * \retval 0 success, page can be placed into transfer
343 * \retval -EAGAIN page is either used by concurrent IO has been
344 * truncated. Skip it.
346 static int vvp_page_make_ready(const struct lu_env *env,
347 const struct cl_page_slice *slice)
349 cfs_page_t *vmpage = cl2vm_page(slice);
350 struct cl_page *pg = slice->cpl_page;
354 /* we're trying to write, but the page is locked.. come back later */
355 if (!TestSetPageLocked(vmpage)) {
356 if (pg->cp_state == CPS_CACHED) {
358 * We can cancel IO if page wasn't dirty after all.
360 clear_page_dirty_for_io(vmpage);
362 * This actually clears the dirty bit in the radix
365 set_page_writeback(vmpage);
366 vvp_write_pending(cl2ccc(slice->cpl_obj),
368 CL_PAGE_HEADER(D_PAGE, env, pg, "readied\n");
372 * Page was concurrently truncated.
374 LASSERT(pg->cp_state == CPS_FREEING);
380 static int vvp_page_print(const struct lu_env *env,
381 const struct cl_page_slice *slice,
382 void *cookie, lu_printer_t printer)
384 struct ccc_page *vp = cl2ccc_page(slice);
385 cfs_page_t *vmpage = vp->cpg_page;
387 (*printer)(env, cookie, LUSTRE_VVP_NAME"-page@%p(%d:%d:%d) "
389 vp, vp->cpg_defer_uptodate, vp->cpg_ra_used,
390 vp->cpg_write_queued, vmpage);
391 if (vmpage != NULL) {
392 (*printer)(env, cookie, "%lx %d:%d %lx %lu %slru",
393 (long)vmpage->flags, page_count(vmpage),
394 page_mapcount(vmpage), vmpage->private,
396 list_empty(&vmpage->lru) ? "not-" : "");
398 (*printer)(env, cookie, "\n");
402 static const struct cl_page_operations vvp_page_ops = {
403 .cpo_own = vvp_page_own,
404 .cpo_assume = vvp_page_assume,
405 .cpo_unassume = vvp_page_unassume,
406 .cpo_disown = vvp_page_disown,
407 .cpo_vmpage = ccc_page_vmpage,
408 .cpo_discard = vvp_page_discard,
409 .cpo_delete = vvp_page_delete,
410 .cpo_unmap = vvp_page_unmap,
411 .cpo_export = vvp_page_export,
412 .cpo_is_vmlocked = vvp_page_is_vmlocked,
413 .cpo_fini = vvp_page_fini,
414 .cpo_print = vvp_page_print,
415 .cpo_is_under_lock = ccc_page_is_under_lock,
418 .cpo_prep = vvp_page_prep_read,
419 .cpo_completion = vvp_page_completion_read,
420 .cpo_make_ready = ccc_fail,
423 .cpo_prep = vvp_page_prep_write,
424 .cpo_completion = vvp_page_completion_write,
425 .cpo_make_ready = vvp_page_make_ready,
430 static void vvp_transient_page_verify(const struct cl_page *page)
432 struct inode *inode = ccc_object_inode(page->cp_obj);
434 LASSERT(!TRYLOCK_INODE_MUTEX(inode));
435 /* LASSERT_SEM_LOCKED(&inode->i_alloc_sem); */
438 static int vvp_transient_page_own(const struct lu_env *env,
439 const struct cl_page_slice *slice,
440 struct cl_io *unused, int nonblock)
442 vvp_transient_page_verify(slice->cpl_page);
446 static void vvp_transient_page_assume(const struct lu_env *env,
447 const struct cl_page_slice *slice,
448 struct cl_io *unused)
450 vvp_transient_page_verify(slice->cpl_page);
453 static void vvp_transient_page_unassume(const struct lu_env *env,
454 const struct cl_page_slice *slice,
455 struct cl_io *unused)
457 vvp_transient_page_verify(slice->cpl_page);
460 static void vvp_transient_page_disown(const struct lu_env *env,
461 const struct cl_page_slice *slice,
462 struct cl_io *unused)
464 vvp_transient_page_verify(slice->cpl_page);
467 static void vvp_transient_page_discard(const struct lu_env *env,
468 const struct cl_page_slice *slice,
469 struct cl_io *unused)
471 struct cl_page *page = slice->cpl_page;
473 vvp_transient_page_verify(slice->cpl_page);
476 * For transient pages, remove it from the radix tree.
478 cl_page_delete(env, page);
481 static int vvp_transient_page_is_vmlocked(const struct lu_env *env,
482 const struct cl_page_slice *slice)
484 struct inode *inode = ccc_object_inode(slice->cpl_obj);
487 locked = !TRYLOCK_INODE_MUTEX(inode);
489 UNLOCK_INODE_MUTEX(inode);
490 return locked ? -EBUSY : -ENODATA;
494 vvp_transient_page_completion(const struct lu_env *env,
495 const struct cl_page_slice *slice,
498 vvp_transient_page_verify(slice->cpl_page);
501 static void vvp_transient_page_fini(const struct lu_env *env,
502 struct cl_page_slice *slice)
504 struct ccc_page *cp = cl2ccc_page(slice);
505 struct cl_page *clp = slice->cpl_page;
506 struct ccc_object *clobj = cl2ccc(clp->cp_obj);
508 vvp_page_fini_common(cp);
509 LASSERT(!TRYLOCK_INODE_MUTEX(clobj->cob_inode));
510 clobj->cob_transient_pages--;
513 static const struct cl_page_operations vvp_transient_page_ops = {
514 .cpo_own = vvp_transient_page_own,
515 .cpo_assume = vvp_transient_page_assume,
516 .cpo_unassume = vvp_transient_page_unassume,
517 .cpo_disown = vvp_transient_page_disown,
518 .cpo_discard = vvp_transient_page_discard,
519 .cpo_vmpage = ccc_page_vmpage,
520 .cpo_fini = vvp_transient_page_fini,
521 .cpo_is_vmlocked = vvp_transient_page_is_vmlocked,
522 .cpo_print = vvp_page_print,
523 .cpo_is_under_lock = ccc_page_is_under_lock,
526 .cpo_prep = ccc_transient_page_prep,
527 .cpo_completion = vvp_transient_page_completion,
530 .cpo_prep = ccc_transient_page_prep,
531 .cpo_completion = vvp_transient_page_completion,
536 struct cl_page *vvp_page_init(const struct lu_env *env, struct cl_object *obj,
537 struct cl_page *page, cfs_page_t *vmpage)
539 struct ccc_page *cpg;
542 CLOBINVRNT(env, obj, ccc_object_invariant(obj));
544 OBD_SLAB_ALLOC_PTR_GFP(cpg, vvp_page_kmem, CFS_ALLOC_IO);
546 cpg->cpg_page = vmpage;
547 page_cache_get(vmpage);
549 CFS_INIT_LIST_HEAD(&cpg->cpg_pending_linkage);
550 if (page->cp_type == CPT_CACHEABLE) {
551 SetPagePrivate(vmpage);
552 vmpage->private = (unsigned long)page;
553 cl_page_slice_add(page, &cpg->cpg_cl, obj,
556 struct ccc_object *clobj = cl2ccc(obj);
558 LASSERT(!TRYLOCK_INODE_MUTEX(clobj->cob_inode));
559 cl_page_slice_add(page, &cpg->cpg_cl, obj,
560 &vvp_transient_page_ops);
561 clobj->cob_transient_pages++;
566 return ERR_PTR(result);