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 2008 Sun Microsystems, Inc. All rights reserved.
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * Implementation of cl_page for VVP layer.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_LLITE
44 # error This file is kernel only.
48 #include <lustre_lite.h>
50 #include "vvp_internal.h"
52 /*****************************************************************************
58 static void vvp_page_fini_common(struct ccc_page *cp)
60 cfs_page_t *vmpage = cp->cpg_page;
62 LASSERT(vmpage != NULL);
63 page_cache_release(vmpage);
64 OBD_SLAB_FREE_PTR(cp, vvp_page_kmem);
67 static void vvp_page_fini(const struct lu_env *env,
68 struct cl_page_slice *slice)
70 struct ccc_page *cp = cl2ccc_page(slice);
71 cfs_page_t *vmpage = cp->cpg_page;
74 * vmpage->private was already cleared when page was moved into
77 LASSERT((struct cl_page *)vmpage->private != slice->cpl_page);
78 vvp_page_fini_common(cp);
81 static void vvp_page_own(const struct lu_env *env,
82 const struct cl_page_slice *slice, struct cl_io *_)
84 struct ccc_page *vpg = cl2ccc_page(slice);
85 cfs_page_t *vmpage = vpg->cpg_page;
87 LASSERT(vmpage != NULL);
89 wait_on_page_writeback(vmpage);
92 static void vvp_page_assume(const struct lu_env *env,
93 const struct cl_page_slice *slice, struct cl_io *_)
95 cfs_page_t *vmpage = cl2vm_page(slice);
97 LASSERT(vmpage != NULL);
98 LASSERT(PageLocked(vmpage));
99 wait_on_page_writeback(vmpage);
102 static void vvp_page_unassume(const struct lu_env *env,
103 const struct cl_page_slice *slice,
106 cfs_page_t *vmpage = cl2vm_page(slice);
108 LASSERT(vmpage != NULL);
109 LASSERT(PageLocked(vmpage));
112 static void vvp_page_disown(const struct lu_env *env,
113 const struct cl_page_slice *slice, struct cl_io *io)
115 cfs_page_t *vmpage = cl2vm_page(slice);
117 LASSERT(vmpage != NULL);
118 LASSERT(PageLocked(vmpage));
120 unlock_page(cl2vm_page(slice));
123 static void vvp_page_discard(const struct lu_env *env,
124 const struct cl_page_slice *slice, struct cl_io *_)
126 cfs_page_t *vmpage = cl2vm_page(slice);
127 struct address_space *mapping = vmpage->mapping;
128 struct ccc_page *cpg = cl2ccc_page(slice);
130 LASSERT(vmpage != NULL);
131 LASSERT(PageLocked(vmpage));
133 if (cpg->cpg_defer_uptodate && !cpg->cpg_ra_used)
134 ll_ra_stats_inc(mapping, RA_STAT_DISCARDED);
137 * truncate_complete_page() calls
138 * a_ops->invalidatepage()->cl_page_delete()->vvp_page_delete().
140 truncate_complete_page(mapping, vmpage);
143 static int vvp_page_unmap(const struct lu_env *env,
144 const struct cl_page_slice *slice, struct cl_io *_)
146 cfs_page_t *vmpage = cl2vm_page(slice);
147 __u64 offset = vmpage->index << CFS_PAGE_SHIFT;
149 LASSERT(vmpage != NULL);
150 LASSERT(PageLocked(vmpage));
152 * XXX is it safe to call this with the page lock held?
154 ll_teardown_mmaps(vmpage->mapping, offset, offset + CFS_PAGE_SIZE);
158 static void vvp_page_delete(const struct lu_env *env,
159 const struct cl_page_slice *slice)
161 cfs_page_t *vmpage = cl2vm_page(slice);
162 struct inode *inode = vmpage->mapping->host;
163 struct cl_object *obj = slice->cpl_obj;
165 LASSERT(PageLocked(vmpage));
166 LASSERT((struct cl_page *)vmpage->private == slice->cpl_page);
167 LASSERT(inode == ccc_object_inode(obj));
169 vvp_write_complete(cl2ccc(obj), cl2ccc_page(slice));
170 ClearPagePrivate(vmpage);
173 * Reference from vmpage to cl_page is removed, but the reference back
174 * is still here. It is removed later in vvp_page_fini().
178 static void vvp_page_export(const struct lu_env *env,
179 const struct cl_page_slice *slice)
181 cfs_page_t *vmpage = cl2vm_page(slice);
183 LASSERT(vmpage != NULL);
184 LASSERT(PageLocked(vmpage));
185 SetPageUptodate(vmpage);
188 static int vvp_page_is_vmlocked(const struct lu_env *env,
189 const struct cl_page_slice *slice)
191 return PageLocked(cl2vm_page(slice)) ? -EBUSY : -ENODATA;
194 static int vvp_page_prep_read(const struct lu_env *env,
195 const struct cl_page_slice *slice,
199 /* Skip the page already marked as PG_uptodate. */
200 RETURN(PageUptodate(cl2vm_page(slice)) ? -EALREADY : 0);
203 static int vvp_page_prep_write(const struct lu_env *env,
204 const struct cl_page_slice *slice,
207 cfs_page_t *vmpage = cl2vm_page(slice);
210 if (clear_page_dirty_for_io(vmpage)) {
211 set_page_writeback(vmpage);
219 * Handles page transfer errors at VM level.
221 * This takes inode as a separate argument, because inode on which error is to
222 * be set can be different from \a vmpage inode in case of direct-io.
224 static void vvp_vmpage_error(struct inode *inode, cfs_page_t *vmpage, int ioret)
227 ClearPageError(vmpage);
228 else if (ioret != -EINTR) {
229 SetPageError(vmpage);
230 if (ioret == -ENOSPC)
231 set_bit(AS_ENOSPC, &inode->i_mapping->flags);
233 set_bit(AS_EIO, &inode->i_mapping->flags);
237 static void vvp_page_completion_common(const struct lu_env *env,
238 struct ccc_page *cp, int ioret)
240 struct cl_page *clp = cp->cpg_cl.cpl_page;
241 cfs_page_t *vmpage = cp->cpg_page;
242 struct inode *inode = ccc_object_inode(clp->cp_obj);
243 struct cl_sync_io *anchor = cp->cpg_sync_io;
245 LINVRNT(cl_page_is_vmlocked(env, clp));
247 if (anchor != NULL) {
248 cp->cpg_sync_io = NULL;
249 cl_sync_io_note(anchor, ioret);
250 } else if (clp->cp_type == CPT_CACHEABLE) {
252 * Don't assert the page writeback bit here because the lustre
253 * file may be as a backend of swap space. in this case, the
254 * page writeback is set by VM, and obvious we shouldn't clear
255 * it at all. Fortunately this type of pages are all TRANSIENT
258 LASSERT(!PageWriteback(vmpage));
261 * Only mark the page error only when it's a cacheable page
264 * For sync IO and direct IO(CPT_TRANSIENT), the error is able
265 * to be seen by application, so we don't need to mark a page
268 vvp_vmpage_error(inode, vmpage, ioret);
273 static void vvp_page_completion_read(const struct lu_env *env,
274 const struct cl_page_slice *slice,
277 struct ccc_page *cp = cl2ccc_page(slice);
278 struct cl_page *page = cl_page_top(slice->cpl_page);
279 struct inode *inode = ccc_object_inode(page->cp_obj);
282 CL_PAGE_HEADER(D_PAGE, env, page, "completing READ with %d\n", ioret);
284 if (cp->cpg_defer_uptodate)
285 ll_ra_count_put(ll_i2sbi(inode), 1);
288 /* XXX: do we need this for transient pages? */
289 if (!cp->cpg_defer_uptodate)
290 cl_page_export(env, page);
292 cp->cpg_defer_uptodate = 0;
293 vvp_page_completion_common(env, cp, ioret);
298 static void vvp_page_completion_write_common(const struct lu_env *env,
299 const struct cl_page_slice *slice,
302 struct ccc_page *cp = cl2ccc_page(slice);
305 * TODO: Actually it makes sense to add the page into oap pending
306 * list again and so that we don't need to take the page out from
307 * SoM write pending list, if we just meet a recoverable error,
309 * To implement this, we just need to return a non zero value in
310 * ->cpo_completion method. The underlying transfer should be notified
311 * and then re-add the page into pending transfer queue. -jay
313 cp->cpg_write_queued = 0;
314 vvp_write_complete(cl2ccc(slice->cpl_obj), cp);
316 vvp_page_completion_common(env, cp, ioret);
319 static void vvp_page_completion_write(const struct lu_env *env,
320 const struct cl_page_slice *slice,
323 struct ccc_page *cp = cl2ccc_page(slice);
324 struct cl_page *pg = slice->cpl_page;
325 cfs_page_t *vmpage = cp->cpg_page;
329 LINVRNT(cl_page_is_vmlocked(env, pg));
330 LASSERT(PageWriteback(vmpage));
332 CL_PAGE_HEADER(D_PAGE, env, pg, "completing WRITE with %d\n", ioret);
334 end_page_writeback(vmpage);
335 LASSERT(!PageWriteback(vmpage));
337 vvp_page_completion_write_common(env, slice, ioret);
342 * Implements cl_page_operations::cpo_make_ready() method.
344 * This is called to yank a page from the transfer cache and to send it out as
345 * a part of transfer. This function try-locks the page. If try-lock failed,
346 * page is owned by some concurrent IO, and should be skipped (this is bad,
347 * but hopefully rare situation, as it usually results in transfer being
348 * shorter than possible).
350 * \retval 0 success, page can be placed into transfer
352 * \retval -EAGAIN page is either used by concurrent IO has been
353 * truncated. Skip it.
355 static int vvp_page_make_ready(const struct lu_env *env,
356 const struct cl_page_slice *slice)
358 cfs_page_t *vmpage = cl2vm_page(slice);
359 struct cl_page *pg = slice->cpl_page;
363 /* we're trying to write, but the page is locked.. come back later */
364 if (!TestSetPageLocked(vmpage)) {
365 if (pg->cp_state == CPS_CACHED) {
367 * We can cancel IO if page wasn't dirty after all.
369 clear_page_dirty_for_io(vmpage);
371 * This actually clears the dirty bit in the radix
374 set_page_writeback(vmpage);
376 CL_PAGE_HEADER(D_PAGE, env, pg, "readied\n");
380 * Page was concurrently truncated.
382 LASSERT(pg->cp_state == CPS_FREEING);
387 static int vvp_page_print(const struct lu_env *env,
388 const struct cl_page_slice *slice,
389 void *cookie, lu_printer_t printer)
391 struct ccc_page *vp = cl2ccc_page(slice);
392 cfs_page_t *vmpage = vp->cpg_page;
394 (*printer)(env, cookie, LUSTRE_VVP_NAME"-page@%p(%d:%d:%d) "
396 vp, vp->cpg_defer_uptodate, vp->cpg_ra_used,
397 vp->cpg_write_queued, vmpage);
398 if (vmpage != NULL) {
399 (*printer)(env, cookie, "%lx %d:%d %lx %lu %slru",
400 (long)vmpage->flags, page_count(vmpage),
401 page_mapcount(vmpage), vmpage->private,
403 list_empty(&vmpage->lru) ? "not-" : "");
405 (*printer)(env, cookie, "\n");
409 static const struct cl_page_operations vvp_page_ops = {
410 .cpo_own = vvp_page_own,
411 .cpo_assume = vvp_page_assume,
412 .cpo_unassume = vvp_page_unassume,
413 .cpo_disown = vvp_page_disown,
414 .cpo_vmpage = ccc_page_vmpage,
415 .cpo_discard = vvp_page_discard,
416 .cpo_delete = vvp_page_delete,
417 .cpo_unmap = vvp_page_unmap,
418 .cpo_export = vvp_page_export,
419 .cpo_is_vmlocked = vvp_page_is_vmlocked,
420 .cpo_fini = vvp_page_fini,
421 .cpo_print = vvp_page_print,
422 .cpo_is_under_lock = ccc_page_is_under_lock,
425 .cpo_prep = vvp_page_prep_read,
426 .cpo_completion = vvp_page_completion_read,
427 .cpo_make_ready = ccc_fail,
430 .cpo_prep = vvp_page_prep_write,
431 .cpo_completion = vvp_page_completion_write,
432 .cpo_make_ready = vvp_page_make_ready,
437 static void vvp_transient_page_verify(const struct cl_page *page)
439 struct inode *inode = ccc_object_inode(page->cp_obj);
441 LASSERT(!TRYLOCK_INODE_MUTEX(inode));
442 /* LASSERT_SEM_LOCKED(&inode->i_alloc_sem); */
445 static void vvp_transient_page_own(const struct lu_env *env,
446 const struct cl_page_slice *slice,
449 vvp_transient_page_verify(slice->cpl_page);
452 static void vvp_transient_page_assume(const struct lu_env *env,
453 const struct cl_page_slice *slice,
456 vvp_transient_page_verify(slice->cpl_page);
459 static void vvp_transient_page_unassume(const struct lu_env *env,
460 const struct cl_page_slice *slice,
463 vvp_transient_page_verify(slice->cpl_page);
466 static void vvp_transient_page_disown(const struct lu_env *env,
467 const struct cl_page_slice *slice,
470 vvp_transient_page_verify(slice->cpl_page);
473 static void vvp_transient_page_discard(const struct lu_env *env,
474 const struct cl_page_slice *slice,
477 struct cl_page *page = slice->cpl_page;
479 vvp_transient_page_verify(slice->cpl_page);
482 * For transient pages, remove it from the radix tree.
484 cl_page_delete(env, page);
487 static int vvp_transient_page_is_vmlocked(const struct lu_env *env,
488 const struct cl_page_slice *slice)
490 struct inode *inode = ccc_object_inode(slice->cpl_obj);
493 locked = !TRYLOCK_INODE_MUTEX(inode);
495 UNLOCK_INODE_MUTEX(inode);
496 return locked ? -EBUSY : -ENODATA;
500 vvp_transient_page_completion_write(const struct lu_env *env,
501 const struct cl_page_slice *slice,
504 vvp_transient_page_verify(slice->cpl_page);
505 vvp_page_completion_write_common(env, slice, ioret);
509 static void vvp_transient_page_fini(const struct lu_env *env,
510 struct cl_page_slice *slice)
512 struct ccc_page *cp = cl2ccc_page(slice);
513 struct cl_page *clp = slice->cpl_page;
514 struct ccc_object *clobj = cl2ccc(clp->cp_obj);
516 vvp_page_fini_common(cp);
517 LASSERT(!TRYLOCK_INODE_MUTEX(clobj->cob_inode));
518 clobj->cob_transient_pages--;
521 static const struct cl_page_operations vvp_transient_page_ops = {
522 .cpo_own = vvp_transient_page_own,
523 .cpo_assume = vvp_transient_page_assume,
524 .cpo_unassume = vvp_transient_page_unassume,
525 .cpo_disown = vvp_transient_page_disown,
526 .cpo_discard = vvp_transient_page_discard,
527 .cpo_vmpage = ccc_page_vmpage,
528 .cpo_fini = vvp_transient_page_fini,
529 .cpo_is_vmlocked = vvp_transient_page_is_vmlocked,
530 .cpo_print = vvp_page_print,
531 .cpo_is_under_lock = ccc_page_is_under_lock,
534 .cpo_prep = ccc_transient_page_prep,
535 .cpo_completion = vvp_page_completion_read,
538 .cpo_prep = ccc_transient_page_prep,
539 .cpo_completion = vvp_transient_page_completion_write,
544 struct cl_page *vvp_page_init(const struct lu_env *env, struct cl_object *obj,
545 struct cl_page *page, cfs_page_t *vmpage)
547 struct ccc_page *cpg;
550 CLOBINVRNT(env, obj, ccc_object_invariant(obj));
552 OBD_SLAB_ALLOC_PTR_GFP(cpg, vvp_page_kmem, CFS_ALLOC_IO);
554 cpg->cpg_page = vmpage;
555 page_cache_get(vmpage);
557 CFS_INIT_LIST_HEAD(&cpg->cpg_pending_linkage);
558 if (page->cp_type == CPT_CACHEABLE) {
559 SetPagePrivate(vmpage);
560 vmpage->private = (unsigned long)page;
561 cl_page_slice_add(page, &cpg->cpg_cl, obj,
564 struct ccc_object *clobj = cl2ccc(obj);
566 LASSERT(!TRYLOCK_INODE_MUTEX(clobj->cob_inode));
567 cl_page_slice_add(page, &cpg->cpg_cl, obj,
568 &vvp_transient_page_ops);
569 clobj->cob_transient_pages++;
574 return ERR_PTR(result);