1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Lustre Lite I/O page cache routines shared by different kernel revs
6 * Copyright (c) 2001-2003 Cluster File Systems, Inc.
8 * This file is part of Lustre, http://www.lustre.org.
10 * Lustre is free software; you can redistribute it and/or
11 * modify it under the terms of version 2 of the GNU General Public
12 * License as published by the Free Software Foundation.
14 * Lustre is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with Lustre; if not, write to the Free Software
21 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #ifndef AUTOCONF_INCLUDED
25 #include <linux/config.h>
27 #include <linux/kernel.h>
29 #include <linux/string.h>
30 #include <linux/stat.h>
31 #include <linux/errno.h>
32 #include <linux/smp_lock.h>
33 #include <linux/unistd.h>
34 #include <linux/version.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
39 #include <linux/stat.h>
40 #include <asm/uaccess.h>
41 #include <asm/segment.h>
43 #include <linux/pagemap.h>
44 #include <linux/smp_lock.h>
46 #define DEBUG_SUBSYSTEM S_LLITE
48 //#include <lustre_mdc.h>
49 #include <lustre_lite.h>
50 #include "llite_internal.h"
51 #include <linux/lustre_compat25.h>
53 #ifndef list_for_each_prev_safe
54 #define list_for_each_prev_safe(pos, n, head) \
55 for (pos = (head)->prev, n = pos->prev; pos != (head); \
56 pos = n, n = pos->prev )
59 cfs_mem_cache_t *ll_async_page_slab = NULL;
60 size_t ll_async_page_slab_size = 0;
62 /* SYNCHRONOUS I/O to object storage for an inode */
63 static int ll_brw(int cmd, struct inode *inode, struct obdo *oa,
64 struct page *page, int flags)
66 struct ll_inode_info *lli = ll_i2info(inode);
67 struct lov_stripe_md *lsm = lli->lli_smd;
68 struct obd_info oinfo = { { { 0 } } };
74 pg.off = ((obd_off)page->index) << CFS_PAGE_SHIFT;
76 if ((cmd & OBD_BRW_WRITE) && (pg.off+CFS_PAGE_SIZE>i_size_read(inode)))
77 pg.count = i_size_read(inode) % CFS_PAGE_SIZE;
79 pg.count = CFS_PAGE_SIZE;
81 LL_CDEBUG_PAGE(D_PAGE, page, "%s %d bytes ino %lu at "LPU64"/"LPX64"\n",
82 cmd & OBD_BRW_WRITE ? "write" : "read", pg.count,
83 inode->i_ino, pg.off, pg.off);
85 CERROR("ZERO COUNT: ino %lu: size %p:%Lu(%p:%Lu) idx %lu off "
86 LPU64"\n", inode->i_ino, inode, i_size_read(inode),
87 page->mapping->host, i_size_read(page->mapping->host),
93 if (cmd & OBD_BRW_WRITE)
94 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_BRW_WRITE,
97 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_BRW_READ,
101 /* NB partial write, so we might not have CAPA_OPC_OSS_READ capa */
102 opc = cmd & OBD_BRW_WRITE ? CAPA_OPC_OSS_WRITE : CAPA_OPC_OSS_RW;
103 oinfo.oi_capa = ll_osscapa_get(inode, opc);
104 rc = obd_brw(cmd, ll_i2dtexp(inode), &oinfo, 1, &pg, NULL);
105 capa_put(oinfo.oi_capa);
107 obdo_to_inode(inode, oa, OBD_MD_FLBLOCKS);
109 CERROR("error from obd_brw: rc = %d\n", rc);
113 /* this isn't where truncate starts. roughly:
114 * sys_truncate->ll_setattr_raw->vmtruncate->ll_truncate. setattr_raw grabs
115 * DLM lock on [size, EOF], i_mutex, ->lli_size_sem, and WRITE_I_ALLOC_SEM to
118 * must be called under ->lli_size_sem */
119 void ll_truncate(struct inode *inode)
121 struct ll_inode_info *lli = ll_i2info(inode);
122 struct obd_info oinfo = { { { 0 } } };
127 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p) to %Lu=%#Lx\n",inode->i_ino,
128 inode->i_generation, inode, i_size_read(inode),
131 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_TRUNC, 1);
132 if (lli->lli_size_sem_owner != current) {
138 CDEBUG(D_INODE, "truncate on inode %lu with no objects\n",
143 LASSERT(atomic_read(&lli->lli_size_sem.count) <= 0);
145 /* XXX I'm pretty sure this is a hack to paper over a more fundamental
147 lov_stripe_lock(lli->lli_smd);
148 inode_init_lvb(inode, &lvb);
149 obd_merge_lvb(ll_i2dtexp(inode), lli->lli_smd, &lvb, 0);
150 if (lvb.lvb_size == i_size_read(inode)) {
151 CDEBUG(D_VFSTRACE, "skipping punch for obj "LPX64", %Lu=%#Lx\n",
152 lli->lli_smd->lsm_object_id, i_size_read(inode),
154 lov_stripe_unlock(lli->lli_smd);
158 obd_adjust_kms(ll_i2dtexp(inode), lli->lli_smd, i_size_read(inode), 1);
159 lov_stripe_unlock(lli->lli_smd);
161 if (unlikely((ll_i2sbi(inode)->ll_flags & LL_SBI_CHECKSUM) &&
162 (i_size_read(inode) & ~CFS_PAGE_MASK))) {
163 /* If the truncate leaves behind a partial page, update its
165 struct page *page = find_get_page(inode->i_mapping,
166 i_size_read(inode) >>
169 struct ll_async_page *llap = llap_cast_private(page);
171 char *kaddr = kmap_atomic(page, KM_USER0);
172 llap->llap_checksum =
173 crc32_le(0, kaddr, CFS_PAGE_SIZE);
174 kunmap_atomic(kaddr, KM_USER0);
176 page_cache_release(page);
180 CDEBUG(D_INFO, "calling punch for "LPX64" (new size %Lu=%#Lx)\n",
181 lli->lli_smd->lsm_object_id, i_size_read(inode), i_size_read(inode));
183 oinfo.oi_md = lli->lli_smd;
184 oinfo.oi_policy.l_extent.start = i_size_read(inode);
185 oinfo.oi_policy.l_extent.end = OBD_OBJECT_EOF;
187 oa.o_id = lli->lli_smd->lsm_object_id;
188 oa.o_gr = lli->lli_smd->lsm_object_gr;
189 oa.o_valid = OBD_MD_FLID | OBD_MD_FLGROUP;
191 obdo_from_inode(&oa, inode, OBD_MD_FLTYPE | OBD_MD_FLMODE |
192 OBD_MD_FLATIME | OBD_MD_FLMTIME | OBD_MD_FLCTIME |
193 OBD_MD_FLFID | OBD_MD_FLGENER);
195 ll_inode_size_unlock(inode, 0);
197 oinfo.oi_capa = ll_osscapa_get(inode, CAPA_OPC_OSS_TRUNC);
198 rc = obd_punch_rqset(ll_i2dtexp(inode), &oinfo, NULL);
199 ll_truncate_free_capa(oinfo.oi_capa);
201 CERROR("obd_truncate fails (%d) ino %lu\n", rc, inode->i_ino);
203 obdo_to_inode(inode, &oa, OBD_MD_FLSIZE | OBD_MD_FLBLOCKS |
204 OBD_MD_FLATIME | OBD_MD_FLMTIME | OBD_MD_FLCTIME);
209 ll_inode_size_unlock(inode, 0);
212 int ll_prepare_write(struct file *file, struct page *page, unsigned from,
215 struct inode *inode = page->mapping->host;
216 struct ll_inode_info *lli = ll_i2info(inode);
217 struct lov_stripe_md *lsm = lli->lli_smd;
218 obd_off offset = ((obd_off)page->index) << CFS_PAGE_SHIFT;
219 struct obd_info oinfo = { { { 0 } } };
226 LASSERT(PageLocked(page));
227 (void)llap_cast_private(page); /* assertion */
229 /* Check to see if we should return -EIO right away */
232 pga.count = CFS_PAGE_SIZE;
235 oa.o_mode = inode->i_mode;
236 oa.o_id = lsm->lsm_object_id;
237 oa.o_gr = lsm->lsm_object_gr;
238 oa.o_valid = OBD_MD_FLID | OBD_MD_FLMODE |
239 OBD_MD_FLTYPE | OBD_MD_FLGROUP;
240 obdo_from_inode(&oa, inode, OBD_MD_FLFID | OBD_MD_FLGENER);
244 rc = obd_brw(OBD_BRW_CHECK, ll_i2dtexp(inode), &oinfo, 1, &pga, NULL);
248 if (PageUptodate(page)) {
249 LL_CDEBUG_PAGE(D_PAGE, page, "uptodate\n");
253 /* We're completely overwriting an existing page, so _don't_ set it up
254 * to date until commit_write */
255 if (from == 0 && to == CFS_PAGE_SIZE) {
256 LL_CDEBUG_PAGE(D_PAGE, page, "full page write\n");
257 POISON_PAGE(page, 0x11);
261 /* If are writing to a new page, no need to read old data. The extent
262 * locking will have updated the KMS, and for our purposes here we can
263 * treat it like i_size. */
264 lov_stripe_lock(lsm);
265 inode_init_lvb(inode, &lvb);
266 obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1);
267 lov_stripe_unlock(lsm);
268 if (lvb.lvb_size <= offset) {
269 char *kaddr = kmap_atomic(page, KM_USER0);
270 LL_CDEBUG_PAGE(D_PAGE, page, "kms "LPU64" <= offset "LPU64"\n",
271 lvb.lvb_size, offset);
272 memset(kaddr, 0, CFS_PAGE_SIZE);
273 kunmap_atomic(kaddr, KM_USER0);
274 GOTO(prepare_done, rc = 0);
277 /* XXX could be an async ocp read.. read-ahead? */
278 rc = ll_brw(OBD_BRW_READ, inode, &oa, page, 0);
280 /* bug 1598: don't clobber blksize */
281 oa.o_valid &= ~(OBD_MD_FLSIZE | OBD_MD_FLBLKSZ);
282 obdo_refresh_inode(inode, &oa, oa.o_valid);
288 SetPageUptodate(page);
293 static int ll_ap_make_ready(void *data, int cmd)
295 struct ll_async_page *llap;
299 llap = LLAP_FROM_COOKIE(data);
300 page = llap->llap_page;
302 LASSERTF(!(cmd & OBD_BRW_READ), "cmd %x page %p ino %lu index %lu\n", cmd, page,
303 page->mapping->host->i_ino, page->index);
305 /* we're trying to write, but the page is locked.. come back later */
306 if (TryLockPage(page))
309 LASSERT(!PageWriteback(page));
311 /* if we left PageDirty we might get another writepage call
312 * in the future. list walkers are bright enough
313 * to check page dirty so we can leave it on whatever list
314 * its on. XXX also, we're called with the cli list so if
315 * we got the page cache list we'd create a lock inversion
316 * with the removepage path which gets the page lock then the
318 LASSERTF(!PageWriteback(page),"cmd %x page %p ino %lu index %lu\n", cmd, page,
319 page->mapping->host->i_ino, page->index);
320 clear_page_dirty_for_io(page);
322 /* This actually clears the dirty bit in the radix tree.*/
323 set_page_writeback(page);
325 LL_CDEBUG_PAGE(D_PAGE, page, "made ready\n");
326 page_cache_get(page);
331 /* We have two reasons for giving llite the opportunity to change the
332 * write length of a given queued page as it builds the RPC containing
335 * 1) Further extending writes may have landed in the page cache
336 * since a partial write first queued this page requiring us
337 * to write more from the page cache. (No further races are possible, since
338 * by the time this is called, the page is locked.)
339 * 2) We might have raced with truncate and want to avoid performing
340 * write RPCs that are just going to be thrown away by the
341 * truncate's punch on the storage targets.
343 * The kms serves these purposes as it is set at both truncate and extending
346 static int ll_ap_refresh_count(void *data, int cmd)
348 struct ll_inode_info *lli;
349 struct ll_async_page *llap;
350 struct lov_stripe_md *lsm;
357 /* readpage queues with _COUNT_STABLE, shouldn't get here. */
358 LASSERT(cmd != OBD_BRW_READ);
360 llap = LLAP_FROM_COOKIE(data);
361 page = llap->llap_page;
362 inode = page->mapping->host;
363 lli = ll_i2info(inode);
366 lov_stripe_lock(lsm);
367 inode_init_lvb(inode, &lvb);
368 obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1);
370 lov_stripe_unlock(lsm);
372 /* catch race with truncate */
373 if (((__u64)page->index << CFS_PAGE_SHIFT) >= kms)
376 /* catch sub-page write at end of file */
377 if (((__u64)page->index << CFS_PAGE_SHIFT) + CFS_PAGE_SIZE > kms)
378 return kms % CFS_PAGE_SIZE;
380 return CFS_PAGE_SIZE;
383 void ll_inode_fill_obdo(struct inode *inode, int cmd, struct obdo *oa)
385 struct lov_stripe_md *lsm;
386 obd_flag valid_flags;
388 lsm = ll_i2info(inode)->lli_smd;
390 oa->o_id = lsm->lsm_object_id;
391 oa->o_gr = lsm->lsm_object_gr;
392 oa->o_valid = OBD_MD_FLID | OBD_MD_FLGROUP;
393 valid_flags = OBD_MD_FLTYPE | OBD_MD_FLATIME;
394 if (cmd & OBD_BRW_WRITE) {
395 oa->o_valid |= OBD_MD_FLEPOCH;
396 oa->o_easize = ll_i2info(inode)->lli_ioepoch;
398 valid_flags |= OBD_MD_FLMTIME | OBD_MD_FLCTIME |
399 OBD_MD_FLUID | OBD_MD_FLGID |
400 OBD_MD_FLFID | OBD_MD_FLGENER;
403 obdo_from_inode(oa, inode, valid_flags);
406 static void ll_ap_fill_obdo(void *data, int cmd, struct obdo *oa)
408 struct ll_async_page *llap;
411 llap = LLAP_FROM_COOKIE(data);
412 ll_inode_fill_obdo(llap->llap_page->mapping->host, cmd, oa);
417 static void ll_ap_update_obdo(void *data, int cmd, struct obdo *oa,
420 struct ll_async_page *llap;
423 llap = LLAP_FROM_COOKIE(data);
424 obdo_from_inode(oa, llap->llap_page->mapping->host, valid);
429 static struct obd_capa *ll_ap_lookup_capa(void *data, int cmd)
431 struct ll_async_page *llap = LLAP_FROM_COOKIE(data);
432 int opc = cmd & OBD_BRW_WRITE ? CAPA_OPC_OSS_WRITE : CAPA_OPC_OSS_RW;
434 return ll_osscapa_get(llap->llap_page->mapping->host, opc);
437 static struct obd_async_page_ops ll_async_page_ops = {
438 .ap_make_ready = ll_ap_make_ready,
439 .ap_refresh_count = ll_ap_refresh_count,
440 .ap_fill_obdo = ll_ap_fill_obdo,
441 .ap_update_obdo = ll_ap_update_obdo,
442 .ap_completion = ll_ap_completion,
443 .ap_lookup_capa = ll_ap_lookup_capa,
446 struct ll_async_page *llap_cast_private(struct page *page)
448 struct ll_async_page *llap = (struct ll_async_page *)page_private(page);
450 LASSERTF(llap == NULL || llap->llap_magic == LLAP_MAGIC,
451 "page %p private %lu gave magic %d which != %d\n",
452 page, page_private(page), llap->llap_magic, LLAP_MAGIC);
457 /* Try to shrink the page cache for the @sbi filesystem by 1/@shrink_fraction.
459 * There is an llap attached onto every page in lustre, linked off @sbi.
460 * We add an llap to the list so we don't lose our place during list walking.
461 * If llaps in the list are being moved they will only move to the end
462 * of the LRU, and we aren't terribly interested in those pages here (we
463 * start at the beginning of the list where the least-used llaps are.
465 int llap_shrink_cache(struct ll_sb_info *sbi, int shrink_fraction)
467 struct ll_async_page *llap, dummy_llap = { .llap_magic = 0xd11ad11a };
468 unsigned long total, want, count = 0;
470 total = sbi->ll_async_page_count;
472 /* There can be a large number of llaps (600k or more in a large
473 * memory machine) so the VM 1/6 shrink ratio is likely too much.
474 * Since we are freeing pages also, we don't necessarily want to
475 * shrink so much. Limit to 40MB of pages + llaps per call. */
476 if (shrink_fraction == 0)
477 want = sbi->ll_async_page_count - sbi->ll_async_page_max + 32;
479 want = (total + shrink_fraction - 1) / shrink_fraction;
481 if (want > 40 << (20 - CFS_PAGE_SHIFT))
482 want = 40 << (20 - CFS_PAGE_SHIFT);
484 CDEBUG(D_CACHE, "shrinking %lu of %lu pages (1/%d)\n",
485 want, total, shrink_fraction);
487 spin_lock(&sbi->ll_lock);
488 list_add(&dummy_llap.llap_pglist_item, &sbi->ll_pglist);
490 while (--total >= 0 && count < want) {
494 if (unlikely(need_resched())) {
495 spin_unlock(&sbi->ll_lock);
497 spin_lock(&sbi->ll_lock);
500 llap = llite_pglist_next_llap(sbi,&dummy_llap.llap_pglist_item);
501 list_del_init(&dummy_llap.llap_pglist_item);
505 page = llap->llap_page;
506 LASSERT(page != NULL);
508 list_add(&dummy_llap.llap_pglist_item, &llap->llap_pglist_item);
510 /* Page needs/undergoing IO */
511 if (TryLockPage(page)) {
512 LL_CDEBUG_PAGE(D_PAGE, page, "can't lock\n");
516 keep = (llap->llap_write_queued || PageDirty(page) ||
517 PageWriteback(page) || (!PageUptodate(page) &&
518 llap->llap_origin != LLAP_ORIGIN_READAHEAD));
520 LL_CDEBUG_PAGE(D_PAGE, page,"%s LRU page: %s%s%s%s%s origin %s\n",
521 keep ? "keep" : "drop",
522 llap->llap_write_queued ? "wq " : "",
523 PageDirty(page) ? "pd " : "",
524 PageUptodate(page) ? "" : "!pu ",
525 PageWriteback(page) ? "wb" : "",
526 llap->llap_defer_uptodate ? "" : "!du",
527 llap_origins[llap->llap_origin]);
529 /* If page is dirty or undergoing IO don't discard it */
535 page_cache_get(page);
536 spin_unlock(&sbi->ll_lock);
538 if (page->mapping != NULL) {
539 ll_teardown_mmaps(page->mapping,
540 (__u64)page->index << CFS_PAGE_SHIFT,
541 ((__u64)page->index << CFS_PAGE_SHIFT)|
543 if (!PageDirty(page) && !page_mapped(page)) {
544 ll_ra_accounting(llap, page->mapping);
545 ll_truncate_complete_page(page);
548 LL_CDEBUG_PAGE(D_PAGE, page, "Not dropping page"
556 page_cache_release(page);
558 spin_lock(&sbi->ll_lock);
560 list_del(&dummy_llap.llap_pglist_item);
561 spin_unlock(&sbi->ll_lock);
563 CDEBUG(D_CACHE, "shrank %lu/%lu and left %lu unscanned\n",
569 struct ll_async_page *llap_from_page(struct page *page, unsigned origin)
571 struct ll_async_page *llap;
572 struct obd_export *exp;
573 struct inode *inode = page->mapping->host;
574 struct ll_sb_info *sbi;
579 static int triggered;
582 LL_CDEBUG_PAGE(D_ERROR, page, "Bug 10047. Wrong anon "
584 libcfs_debug_dumpstack(NULL);
587 RETURN(ERR_PTR(-EINVAL));
589 sbi = ll_i2sbi(inode);
590 LASSERT(ll_async_page_slab);
591 LASSERTF(origin < LLAP__ORIGIN_MAX, "%u\n", origin);
593 llap = llap_cast_private(page);
595 /* move to end of LRU list, except when page is just about to
597 if (origin != LLAP_ORIGIN_REMOVEPAGE) {
598 spin_lock(&sbi->ll_lock);
599 sbi->ll_pglist_gen++;
600 list_del_init(&llap->llap_pglist_item);
601 list_add_tail(&llap->llap_pglist_item, &sbi->ll_pglist);
602 spin_unlock(&sbi->ll_lock);
607 exp = ll_i2dtexp(page->mapping->host);
609 RETURN(ERR_PTR(-EINVAL));
611 /* limit the number of lustre-cached pages */
612 if (sbi->ll_async_page_count >= sbi->ll_async_page_max)
613 llap_shrink_cache(sbi, 0);
615 OBD_SLAB_ALLOC(llap, ll_async_page_slab, CFS_ALLOC_STD,
616 ll_async_page_slab_size);
618 RETURN(ERR_PTR(-ENOMEM));
619 llap->llap_magic = LLAP_MAGIC;
620 llap->llap_cookie = (void *)llap + size_round(sizeof(*llap));
622 rc = obd_prep_async_page(exp, ll_i2info(inode)->lli_smd, NULL, page,
623 (obd_off)page->index << CFS_PAGE_SHIFT,
624 &ll_async_page_ops, llap, &llap->llap_cookie);
626 OBD_SLAB_FREE(llap, ll_async_page_slab,
627 ll_async_page_slab_size);
631 CDEBUG(D_CACHE, "llap %p page %p cookie %p obj off "LPU64"\n", llap,
632 page, llap->llap_cookie, (obd_off)page->index << CFS_PAGE_SHIFT);
633 /* also zeroing the PRIVBITS low order bitflags */
634 __set_page_ll_data(page, llap);
635 llap->llap_page = page;
636 spin_lock(&sbi->ll_lock);
637 sbi->ll_pglist_gen++;
638 sbi->ll_async_page_count++;
639 list_add_tail(&llap->llap_pglist_item, &sbi->ll_pglist);
640 INIT_LIST_HEAD(&llap->llap_pending_write);
641 spin_unlock(&sbi->ll_lock);
644 if (unlikely(sbi->ll_flags & LL_SBI_CHECKSUM)) {
646 char *kaddr = kmap_atomic(page, KM_USER0);
647 csum = crc32_le(csum, kaddr, CFS_PAGE_SIZE);
648 kunmap_atomic(kaddr, KM_USER0);
649 if (origin == LLAP_ORIGIN_READAHEAD ||
650 origin == LLAP_ORIGIN_READPAGE) {
651 llap->llap_checksum = 0;
652 } else if (origin == LLAP_ORIGIN_COMMIT_WRITE ||
653 llap->llap_checksum == 0) {
654 llap->llap_checksum = csum;
655 CDEBUG(D_PAGE, "page %p cksum %x\n", page, csum);
656 } else if (llap->llap_checksum == csum) {
657 /* origin == LLAP_ORIGIN_WRITEPAGE */
658 CDEBUG(D_PAGE, "page %p cksum %x confirmed\n",
661 /* origin == LLAP_ORIGIN_WRITEPAGE */
662 LL_CDEBUG_PAGE(D_ERROR, page, "old cksum %x != new "
663 "%x!\n", llap->llap_checksum, csum);
667 llap->llap_origin = origin;
671 static int queue_or_sync_write(struct obd_export *exp, struct inode *inode,
672 struct ll_async_page *llap,
673 unsigned to, obd_flag async_flags)
675 unsigned long size_index = i_size_read(inode) >> CFS_PAGE_SHIFT;
676 struct obd_io_group *oig;
677 struct ll_sb_info *sbi = ll_i2sbi(inode);
678 int rc, noquot = llap->llap_ignore_quota ? OBD_BRW_NOQUOTA : 0;
681 /* _make_ready only sees llap once we've unlocked the page */
682 llap->llap_write_queued = 1;
683 rc = obd_queue_async_io(exp, ll_i2info(inode)->lli_smd, NULL,
684 llap->llap_cookie, OBD_BRW_WRITE | noquot,
685 0, 0, 0, async_flags);
687 LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, "write queued\n");
691 llap->llap_write_queued = 0;
692 /* Do not pass llap here as it is sync write. */
693 llap_write_pending(inode, NULL);
699 /* make full-page requests if we are not at EOF (bug 4410) */
700 if (to != CFS_PAGE_SIZE && llap->llap_page->index < size_index) {
701 LL_CDEBUG_PAGE(D_PAGE, llap->llap_page,
702 "sync write before EOF: size_index %lu, to %d\n",
705 } else if (to != CFS_PAGE_SIZE && llap->llap_page->index == size_index) {
706 int size_to = i_size_read(inode) & ~CFS_PAGE_MASK;
707 LL_CDEBUG_PAGE(D_PAGE, llap->llap_page,
708 "sync write at EOF: size_index %lu, to %d/%d\n",
709 size_index, to, size_to);
714 /* compare the checksum once before the page leaves llite */
715 if (unlikely((sbi->ll_flags & LL_SBI_CHECKSUM) &&
716 llap->llap_checksum != 0)) {
718 struct page *page = llap->llap_page;
719 char *kaddr = kmap_atomic(page, KM_USER0);
720 csum = crc32_le(csum, kaddr, CFS_PAGE_SIZE);
721 kunmap_atomic(kaddr, KM_USER0);
722 if (llap->llap_checksum == csum) {
723 CDEBUG(D_PAGE, "page %p cksum %x confirmed\n",
726 CERROR("page %p old cksum %x != new cksum %x!\n",
727 page, llap->llap_checksum, csum);
731 rc = obd_queue_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig,
732 llap->llap_cookie, OBD_BRW_WRITE | noquot,
733 0, to, 0, ASYNC_READY | ASYNC_URGENT |
734 ASYNC_COUNT_STABLE | ASYNC_GROUP_SYNC);
738 rc = obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig);
744 if (!rc && async_flags & ASYNC_READY) {
745 unlock_page(llap->llap_page);
746 if (PageWriteback(llap->llap_page)) {
747 end_page_writeback(llap->llap_page);
751 if (rc == 0 && llap_write_complete(inode, llap))
752 ll_queue_done_writing(inode, 0);
754 LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, "sync write returned %d\n", rc);
762 /* update our write count to account for i_size increases that may have
763 * happened since we've queued the page for io. */
765 /* be careful not to return success without setting the page Uptodate or
766 * the next pass through prepare_write will read in stale data from disk. */
767 int ll_commit_write(struct file *file, struct page *page, unsigned from,
770 struct inode *inode = page->mapping->host;
771 struct ll_inode_info *lli = ll_i2info(inode);
772 struct lov_stripe_md *lsm = lli->lli_smd;
773 struct obd_export *exp;
774 struct ll_async_page *llap;
779 SIGNAL_MASK_ASSERT(); /* XXX BUG 1511 */
780 LASSERT(inode == file->f_dentry->d_inode);
781 LASSERT(PageLocked(page));
783 CDEBUG(D_INODE, "inode %p is writing page %p from %d to %d at %lu\n",
784 inode, page, from, to, page->index);
786 llap = llap_from_page(page, LLAP_ORIGIN_COMMIT_WRITE);
788 RETURN(PTR_ERR(llap));
790 exp = ll_i2dtexp(inode);
794 llap->llap_ignore_quota = capable(CAP_SYS_RESOURCE);
797 * queue a write for some time in the future the first time we
800 * This is different from what other file systems do: they usually
801 * just mark page (and some of its buffers) dirty and rely on
802 * balance_dirty_pages() to start a write-back. Lustre wants write-back
803 * to be started earlier for the following reasons:
805 * (1) with a large number of clients we need to limit the amount
806 * of cached data on the clients a lot;
808 * (2) large compute jobs generally want compute-only then io-only
809 * and the IO should complete as quickly as possible;
811 * (3) IO is batched up to the RPC size and is async until the
812 * client max cache is hit
813 * (/proc/fs/lustre/osc/OSC.../max_dirty_mb)
816 if (!PageDirty(page)) {
817 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRTY_MISSES, 1);
819 rc = queue_or_sync_write(exp, inode, llap, to, 0);
823 ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRTY_HITS, 1);
826 /* put the page in the page cache, from now on ll_removepage is
827 * responsible for cleaning up the llap.
828 * only set page dirty when it's queued to be write out */
829 if (llap->llap_write_queued)
830 set_page_dirty(page);
833 size = (((obd_off)page->index) << CFS_PAGE_SHIFT) + to;
834 ll_inode_size_lock(inode, 0);
836 lov_stripe_lock(lsm);
837 obd_adjust_kms(exp, lsm, size, 0);
838 lov_stripe_unlock(lsm);
839 if (size > i_size_read(inode))
840 i_size_write(inode, size);
841 SetPageUptodate(page);
842 } else if (size > i_size_read(inode)) {
843 /* this page beyond the pales of i_size, so it can't be
844 * truncated in ll_p_r_e during lock revoking. we must
845 * teardown our book-keeping here. */
848 ll_inode_size_unlock(inode, 0);
852 static unsigned long ll_ra_count_get(struct ll_sb_info *sbi, unsigned long len)
854 struct ll_ra_info *ra = &sbi->ll_ra_info;
858 spin_lock(&sbi->ll_lock);
859 ret = min(ra->ra_max_pages - ra->ra_cur_pages, len);
860 ra->ra_cur_pages += ret;
861 spin_unlock(&sbi->ll_lock);
866 static void ll_ra_count_put(struct ll_sb_info *sbi, unsigned long len)
868 struct ll_ra_info *ra = &sbi->ll_ra_info;
869 spin_lock(&sbi->ll_lock);
870 LASSERTF(ra->ra_cur_pages >= len, "r_c_p %lu len %lu\n",
871 ra->ra_cur_pages, len);
872 ra->ra_cur_pages -= len;
873 spin_unlock(&sbi->ll_lock);
876 /* called for each page in a completed rpc.*/
877 int ll_ap_completion(void *data, int cmd, struct obdo *oa, int rc)
879 struct ll_async_page *llap;
884 llap = LLAP_FROM_COOKIE(data);
885 page = llap->llap_page;
886 LASSERT(PageLocked(page));
887 LASSERT(CheckWriteback(page,cmd));
889 LL_CDEBUG_PAGE(D_PAGE, page, "completing cmd %d with %d\n", cmd, rc);
891 if (cmd & OBD_BRW_READ && llap->llap_defer_uptodate)
892 ll_ra_count_put(ll_i2sbi(page->mapping->host), 1);
895 if (cmd & OBD_BRW_READ) {
896 if (!llap->llap_defer_uptodate)
897 SetPageUptodate(page);
899 llap->llap_write_queued = 0;
901 ClearPageError(page);
903 if (cmd & OBD_BRW_READ) {
904 llap->llap_defer_uptodate = 0;
908 set_bit(AS_ENOSPC, &page->mapping->flags);
910 set_bit(AS_EIO, &page->mapping->flags);
915 if (cmd & OBD_BRW_WRITE) {
916 /* Only rc == 0, write succeed, then this page could be deleted
917 * from the pending_writing list
919 if (rc == 0 && llap_write_complete(page->mapping->host, llap))
920 ll_queue_done_writing(page->mapping->host, 0);
923 if (PageWriteback(page)) {
924 end_page_writeback(page);
926 page_cache_release(page);
931 /* the kernel calls us here when a page is unhashed from the page cache.
932 * the page will be locked and the kernel is holding a spinlock, so
933 * we need to be careful. we're just tearing down our book-keeping
935 void ll_removepage(struct page *page)
937 struct inode *inode = page->mapping->host;
938 struct obd_export *exp;
939 struct ll_async_page *llap;
940 struct ll_sb_info *sbi = ll_i2sbi(inode);
944 LASSERT(!in_interrupt());
946 /* sync pages or failed read pages can leave pages in the page
947 * cache that don't have our data associated with them anymore */
948 if (page_private(page) == 0) {
953 LL_CDEBUG_PAGE(D_PAGE, page, "being evicted\n");
955 exp = ll_i2dtexp(inode);
957 CERROR("page %p ind %lu gave null export\n", page, page->index);
962 llap = llap_from_page(page, LLAP_ORIGIN_REMOVEPAGE);
964 CERROR("page %p ind %lu couldn't find llap: %ld\n", page,
965 page->index, PTR_ERR(llap));
970 if (llap_write_complete(inode, llap))
971 ll_queue_done_writing(inode, 0);
973 rc = obd_teardown_async_page(exp, ll_i2info(inode)->lli_smd, NULL,
976 CERROR("page %p ind %lu failed: %d\n", page, page->index, rc);
978 /* this unconditional free is only safe because the page lock
979 * is providing exclusivity to memory pressure/truncate/writeback..*/
980 __clear_page_ll_data(page);
982 spin_lock(&sbi->ll_lock);
983 if (!list_empty(&llap->llap_pglist_item))
984 list_del_init(&llap->llap_pglist_item);
985 sbi->ll_pglist_gen++;
986 sbi->ll_async_page_count--;
987 spin_unlock(&sbi->ll_lock);
988 OBD_SLAB_FREE(llap, ll_async_page_slab, ll_async_page_slab_size);
992 static int ll_page_matches(struct page *page, int fd_flags)
994 struct lustre_handle match_lockh = {0};
995 struct inode *inode = page->mapping->host;
996 ldlm_policy_data_t page_extent;
1000 if (unlikely(fd_flags & LL_FILE_GROUP_LOCKED))
1003 page_extent.l_extent.start = (__u64)page->index << CFS_PAGE_SHIFT;
1004 page_extent.l_extent.end =
1005 page_extent.l_extent.start + CFS_PAGE_SIZE - 1;
1006 flags = LDLM_FL_TEST_LOCK | LDLM_FL_BLOCK_GRANTED;
1007 if (!(fd_flags & LL_FILE_READAHEAD))
1008 flags |= LDLM_FL_CBPENDING;
1009 matches = obd_match(ll_i2sbi(inode)->ll_dt_exp,
1010 ll_i2info(inode)->lli_smd, LDLM_EXTENT,
1011 &page_extent, LCK_PR | LCK_PW, &flags, inode,
1016 static int ll_issue_page_read(struct obd_export *exp,
1017 struct ll_async_page *llap,
1018 struct obd_io_group *oig, int defer)
1020 struct page *page = llap->llap_page;
1023 page_cache_get(page);
1024 llap->llap_defer_uptodate = defer;
1025 llap->llap_ra_used = 0;
1026 rc = obd_queue_group_io(exp, ll_i2info(page->mapping->host)->lli_smd,
1027 NULL, oig, llap->llap_cookie, OBD_BRW_READ, 0,
1028 CFS_PAGE_SIZE, 0, ASYNC_COUNT_STABLE |
1029 ASYNC_READY | ASYNC_URGENT);
1031 LL_CDEBUG_PAGE(D_ERROR, page, "read queue failed: rc %d\n", rc);
1032 page_cache_release(page);
1037 static void ll_ra_stats_inc_unlocked(struct ll_ra_info *ra, enum ra_stat which)
1039 LASSERTF(which >= 0 && which < _NR_RA_STAT, "which: %u\n", which);
1040 ra->ra_stats[which]++;
1043 static void ll_ra_stats_inc(struct address_space *mapping, enum ra_stat which)
1045 struct ll_sb_info *sbi = ll_i2sbi(mapping->host);
1046 struct ll_ra_info *ra = &ll_i2sbi(mapping->host)->ll_ra_info;
1048 spin_lock(&sbi->ll_lock);
1049 ll_ra_stats_inc_unlocked(ra, which);
1050 spin_unlock(&sbi->ll_lock);
1053 void ll_ra_accounting(struct ll_async_page *llap, struct address_space *mapping)
1055 if (!llap->llap_defer_uptodate || llap->llap_ra_used)
1058 ll_ra_stats_inc(mapping, RA_STAT_DISCARDED);
1061 #define RAS_CDEBUG(ras) \
1063 "lrp %lu cr %lu cp %lu ws %lu wl %lu nra %lu r %lu ri %lu\n", \
1064 ras->ras_last_readpage, ras->ras_consecutive_requests, \
1065 ras->ras_consecutive_pages, ras->ras_window_start, \
1066 ras->ras_window_len, ras->ras_next_readahead, \
1067 ras->ras_requests, ras->ras_request_index);
1069 static int index_in_window(unsigned long index, unsigned long point,
1070 unsigned long before, unsigned long after)
1072 unsigned long start = point - before, end = point + after;
1079 return start <= index && index <= end;
1082 static struct ll_readahead_state *ll_ras_get(struct file *f)
1084 struct ll_file_data *fd;
1086 fd = LUSTRE_FPRIVATE(f);
1090 void ll_ra_read_in(struct file *f, struct ll_ra_read *rar)
1092 struct ll_readahead_state *ras;
1094 ras = ll_ras_get(f);
1096 spin_lock(&ras->ras_lock);
1097 ras->ras_requests++;
1098 ras->ras_request_index = 0;
1099 ras->ras_consecutive_requests++;
1100 rar->lrr_reader = current;
1102 list_add(&rar->lrr_linkage, &ras->ras_read_beads);
1103 spin_unlock(&ras->ras_lock);
1106 void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar)
1108 struct ll_readahead_state *ras;
1110 ras = ll_ras_get(f);
1112 spin_lock(&ras->ras_lock);
1113 list_del_init(&rar->lrr_linkage);
1114 spin_unlock(&ras->ras_lock);
1117 static struct ll_ra_read *ll_ra_read_get_locked(struct ll_readahead_state *ras)
1119 struct ll_ra_read *scan;
1121 list_for_each_entry(scan, &ras->ras_read_beads, lrr_linkage) {
1122 if (scan->lrr_reader == current)
1128 struct ll_ra_read *ll_ra_read_get(struct file *f)
1130 struct ll_readahead_state *ras;
1131 struct ll_ra_read *bead;
1133 ras = ll_ras_get(f);
1135 spin_lock(&ras->ras_lock);
1136 bead = ll_ra_read_get_locked(ras);
1137 spin_unlock(&ras->ras_lock);
1141 static int ll_readahead(struct ll_readahead_state *ras,
1142 struct obd_export *exp, struct address_space *mapping,
1143 struct obd_io_group *oig, int flags)
1145 unsigned long i, start = 0, end = 0, reserved;
1146 struct ll_async_page *llap;
1148 int rc, ret = 0, match_failed = 0;
1150 unsigned int gfp_mask;
1151 struct inode *inode;
1152 struct lov_stripe_md *lsm;
1153 struct ll_ra_read *bead;
1157 inode = mapping->host;
1158 lsm = ll_i2info(inode)->lli_smd;
1160 lov_stripe_lock(lsm);
1161 inode_init_lvb(inode, &lvb);
1162 obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1);
1164 lov_stripe_unlock(lsm);
1166 ll_ra_stats_inc(mapping, RA_STAT_ZERO_LEN);
1170 spin_lock(&ras->ras_lock);
1171 bead = ll_ra_read_get_locked(ras);
1172 /* Enlarge the RA window to encompass the full read */
1173 if (bead != NULL && ras->ras_window_start + ras->ras_window_len <
1174 bead->lrr_start + bead->lrr_count) {
1175 ras->ras_window_len = bead->lrr_start + bead->lrr_count -
1176 ras->ras_window_start;
1178 /* Reserve a part of the read-ahead window that we'll be issuing */
1179 if (ras->ras_window_len) {
1180 start = ras->ras_next_readahead;
1181 end = ras->ras_window_start + ras->ras_window_len - 1;
1184 /* Truncate RA window to end of file */
1185 end = min(end, (unsigned long)((kms - 1) >> CFS_PAGE_SHIFT));
1186 ras->ras_next_readahead = max(end, end + 1);
1189 spin_unlock(&ras->ras_lock);
1192 ll_ra_stats_inc(mapping, RA_STAT_ZERO_WINDOW);
1196 reserved = ll_ra_count_get(ll_i2sbi(inode), end - start + 1);
1197 if (reserved < end - start + 1)
1198 ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT);
1200 gfp_mask = GFP_HIGHUSER & ~__GFP_WAIT;
1202 gfp_mask |= __GFP_NOWARN;
1205 for (i = start; reserved > 0 && !match_failed && i <= end; i++) {
1206 /* skip locked pages from previous readpage calls */
1207 page = grab_cache_page_nowait_gfp(mapping, i, gfp_mask);
1209 ll_ra_stats_inc(mapping, RA_STAT_FAILED_GRAB_PAGE);
1210 CDEBUG(D_READA, "g_c_p_n failed\n");
1214 /* Check if page was truncated or reclaimed */
1215 if (page->mapping != mapping) {
1216 ll_ra_stats_inc(mapping, RA_STAT_WRONG_GRAB_PAGE);
1217 CDEBUG(D_READA, "g_c_p_n returned invalid page\n");
1221 /* we do this first so that we can see the page in the /proc
1223 llap = llap_from_page(page, LLAP_ORIGIN_READAHEAD);
1224 if (IS_ERR(llap) || llap->llap_defer_uptodate)
1227 /* skip completed pages */
1228 if (Page_Uptodate(page))
1231 /* bail when we hit the end of the lock. */
1232 if ((rc = ll_page_matches(page, flags|LL_FILE_READAHEAD)) <= 0){
1233 LL_CDEBUG_PAGE(D_READA | D_PAGE, page,
1234 "lock match failed: rc %d\n", rc);
1235 ll_ra_stats_inc(mapping, RA_STAT_FAILED_MATCH);
1240 rc = ll_issue_page_read(exp, llap, oig, 1);
1244 LL_CDEBUG_PAGE(D_READA| D_PAGE, page,
1245 "started read-ahead\n");
1248 LL_CDEBUG_PAGE(D_READA | D_PAGE, page,
1249 "skipping read-ahead\n");
1253 page_cache_release(page);
1256 LASSERTF(reserved >= 0, "reserved %lu\n", reserved);
1258 ll_ra_count_put(ll_i2sbi(inode), reserved);
1259 if (i == end + 1 && end == (kms >> CFS_PAGE_SHIFT))
1260 ll_ra_stats_inc(mapping, RA_STAT_EOF);
1262 /* if we didn't get to the end of the region we reserved from
1263 * the ras we need to go back and update the ras so that the
1264 * next read-ahead tries from where we left off. we only do so
1265 * if the region we failed to issue read-ahead on is still ahead
1266 * of the app and behind the next index to start read-ahead from */
1268 spin_lock(&ras->ras_lock);
1269 if (i < ras->ras_next_readahead &&
1270 index_in_window(i, ras->ras_window_start, 0,
1271 ras->ras_window_len)) {
1272 ras->ras_next_readahead = i;
1275 spin_unlock(&ras->ras_lock);
1281 static void ras_set_start(struct ll_readahead_state *ras, unsigned long index)
1283 ras->ras_window_start = index & (~((1024 * 1024 >> CFS_PAGE_SHIFT) - 1));
1286 /* called with the ras_lock held or from places where it doesn't matter */
1287 static void ras_reset(struct ll_readahead_state *ras, unsigned long index)
1289 ras->ras_last_readpage = index;
1290 ras->ras_consecutive_requests = 0;
1291 ras->ras_consecutive_pages = 0;
1292 ras->ras_window_len = 0;
1293 ras_set_start(ras, index);
1294 ras->ras_next_readahead = max(ras->ras_window_start, index);
1299 void ll_readahead_init(struct inode *inode, struct ll_readahead_state *ras)
1301 spin_lock_init(&ras->ras_lock);
1303 ras->ras_requests = 0;
1304 INIT_LIST_HEAD(&ras->ras_read_beads);
1307 static void ras_update(struct ll_sb_info *sbi, struct inode *inode,
1308 struct ll_readahead_state *ras, unsigned long index,
1311 struct ll_ra_info *ra = &sbi->ll_ra_info;
1315 spin_lock(&sbi->ll_lock);
1316 spin_lock(&ras->ras_lock);
1318 ll_ra_stats_inc_unlocked(ra, hit ? RA_STAT_HIT : RA_STAT_MISS);
1320 /* reset the read-ahead window in two cases. First when the app seeks
1321 * or reads to some other part of the file. Secondly if we get a
1322 * read-ahead miss that we think we've previously issued. This can
1323 * be a symptom of there being so many read-ahead pages that the VM is
1324 * reclaiming it before we get to it. */
1325 if (!index_in_window(index, ras->ras_last_readpage, 8, 8)) {
1327 ll_ra_stats_inc_unlocked(ra, RA_STAT_DISTANT_READPAGE);
1328 } else if (!hit && ras->ras_window_len &&
1329 index < ras->ras_next_readahead &&
1330 index_in_window(index, ras->ras_window_start, 0,
1331 ras->ras_window_len)) {
1333 ll_ra_stats_inc_unlocked(ra, RA_STAT_MISS_IN_WINDOW);
1336 /* On the second access to a file smaller than the tunable
1337 * ra_max_read_ahead_whole_pages trigger RA on all pages in the
1338 * file up to ra_max_pages. This is simply a best effort and
1339 * only occurs once per open file. Normal RA behavior is reverted
1340 * to for subsequent IO. The mmap case does not increment
1341 * ras_requests and thus can never trigger this behavior. */
1342 if (ras->ras_requests == 2 && !ras->ras_request_index) {
1345 kms_pages = (i_size_read(inode) + CFS_PAGE_SIZE - 1) >>
1348 CDEBUG(D_READA, "kmsp "LPU64" mwp %lu mp %lu\n", kms_pages,
1349 ra->ra_max_read_ahead_whole_pages, ra->ra_max_pages);
1352 kms_pages <= ra->ra_max_read_ahead_whole_pages) {
1353 ras->ras_window_start = 0;
1354 ras->ras_last_readpage = 0;
1355 ras->ras_next_readahead = 0;
1356 ras->ras_window_len = min(ra->ra_max_pages,
1357 ra->ra_max_read_ahead_whole_pages);
1358 GOTO(out_unlock, 0);
1363 ras_reset(ras, index);
1364 GOTO(out_unlock, 0);
1367 ras->ras_last_readpage = index;
1368 ras->ras_consecutive_pages++;
1369 ras_set_start(ras, index);
1370 ras->ras_next_readahead = max(ras->ras_window_start,
1371 ras->ras_next_readahead);
1373 /* Trigger RA in the mmap case where ras_consecutive_requests
1374 * is not incremented and thus can't be used to trigger RA */
1375 if (!ras->ras_window_len && ras->ras_consecutive_pages == 3) {
1376 ras->ras_window_len = 1024 * 1024 >> CFS_PAGE_SHIFT;
1377 GOTO(out_unlock, 0);
1380 /* The initial ras_window_len is set to the request size. To avoid
1381 * uselessly reading and discarding pages for random IO the window is
1382 * only increased once per consecutive request received. */
1383 if (ras->ras_consecutive_requests > 1 && !ras->ras_request_index) {
1384 ras->ras_window_len = min(ras->ras_window_len +
1385 (1024 * 1024 >> CFS_PAGE_SHIFT),
1392 ras->ras_request_index++;
1393 spin_unlock(&ras->ras_lock);
1394 spin_unlock(&sbi->ll_lock);
1398 int ll_writepage(struct page *page)
1400 struct inode *inode = page->mapping->host;
1401 struct ll_inode_info *lli = ll_i2info(inode);
1402 struct obd_export *exp;
1403 struct ll_async_page *llap;
1407 LASSERT(!PageDirty(page));
1408 LASSERT(PageLocked(page));
1410 exp = ll_i2dtexp(inode);
1412 GOTO(out, rc = -EINVAL);
1414 llap = llap_from_page(page, LLAP_ORIGIN_WRITEPAGE);
1416 GOTO(out, rc = PTR_ERR(llap));
1418 LASSERT(!PageWriteback(page));
1419 set_page_writeback(page);
1421 page_cache_get(page);
1422 if (llap->llap_write_queued) {
1423 LL_CDEBUG_PAGE(D_PAGE, page, "marking urgent\n");
1424 rc = obd_set_async_flags(exp, lli->lli_smd, NULL,
1426 ASYNC_READY | ASYNC_URGENT);
1428 rc = queue_or_sync_write(exp, inode, llap, CFS_PAGE_SIZE,
1429 ASYNC_READY | ASYNC_URGENT);
1432 page_cache_release(page);
1435 if (!lli->lli_async_rc)
1436 lli->lli_async_rc = rc;
1437 /* re-dirty page on error so it retries write */
1438 if (PageWriteback(page)) {
1439 end_page_writeback(page);
1441 /* resend page only for not started IO*/
1442 if (!PageError(page))
1443 ll_redirty_page(page);
1450 * for now we do our readpage the same on both 2.4 and 2.5. The kernel's
1451 * read-ahead assumes it is valid to issue readpage all the way up to
1452 * i_size, but our dlm locks make that not the case. We disable the
1453 * kernel's read-ahead and do our own by walking ahead in the page cache
1454 * checking for dlm lock coverage. the main difference between 2.4 and
1455 * 2.6 is how read-ahead gets batched and issued, but we're using our own,
1456 * so they look the same.
1458 int ll_readpage(struct file *filp, struct page *page)
1460 struct ll_file_data *fd = LUSTRE_FPRIVATE(filp);
1461 struct inode *inode = page->mapping->host;
1462 struct obd_export *exp;
1463 struct ll_async_page *llap;
1464 struct obd_io_group *oig = NULL;
1468 LASSERT(PageLocked(page));
1469 LASSERT(!PageUptodate(page));
1470 CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p),offset=%Lu=%#Lx\n",
1471 inode->i_ino, inode->i_generation, inode,
1472 (((loff_t)page->index) << CFS_PAGE_SHIFT),
1473 (((loff_t)page->index) << CFS_PAGE_SHIFT));
1474 LASSERT(atomic_read(&filp->f_dentry->d_inode->i_count) > 0);
1476 if (!ll_i2info(inode)->lli_smd) {
1477 /* File with no objects - one big hole */
1478 /* We use this just for remove_from_page_cache that is not
1479 * exported, we'd make page back up to date. */
1480 ll_truncate_complete_page(page);
1481 clear_page(kmap(page));
1483 SetPageUptodate(page);
1488 rc = oig_init(&oig);
1492 exp = ll_i2dtexp(inode);
1494 GOTO(out, rc = -EINVAL);
1496 llap = llap_from_page(page, LLAP_ORIGIN_READPAGE);
1498 GOTO(out, rc = PTR_ERR(llap));
1500 if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages)
1501 ras_update(ll_i2sbi(inode), inode, &fd->fd_ras, page->index,
1502 llap->llap_defer_uptodate);
1504 if (llap->llap_defer_uptodate) {
1505 llap->llap_ra_used = 1;
1506 rc = ll_readahead(&fd->fd_ras, exp, page->mapping, oig,
1509 obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd,
1511 LL_CDEBUG_PAGE(D_PAGE, page, "marking uptodate from defer\n");
1512 SetPageUptodate(page);
1514 GOTO(out_oig, rc = 0);
1517 if (likely((fd->fd_flags & LL_FILE_IGNORE_LOCK) == 0)) {
1518 rc = ll_page_matches(page, fd->fd_flags);
1520 LL_CDEBUG_PAGE(D_ERROR, page, "lock match failed: rc %d\n", rc);
1525 CWARN("ino %lu page %lu (%llu) not covered by "
1526 "a lock (mmap?). check debug logs.\n",
1527 inode->i_ino, page->index,
1528 (long long)page->index << CFS_PAGE_SHIFT);
1532 rc = ll_issue_page_read(exp, llap, oig, 0);
1536 LL_CDEBUG_PAGE(D_PAGE, page, "queued readpage\n");
1537 if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages)
1538 ll_readahead(&fd->fd_ras, exp, page->mapping, oig,
1541 rc = obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig);