X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=blobdiff_plain;f=lustre%2Fllite%2Frw.c;h=3d62c588e1a8dbe0e08bb1c7e16a286e3900e099;hp=df7ab9be33cea4bb23dd9a1947af7081be6edf6d;hb=c4b74bf9e14a113e531d2d38a294a870ef3e0593;hpb=090c677210ee2946d99c71412e4ff762bb300f4f diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c index df7ab9b..3d62c58 100644 --- a/lustre/llite/rw.c +++ b/lustre/llite/rw.c @@ -1,27 +1,44 @@ /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * - * Lustre Lite I/O page cache routines shared by different kernel revs + * 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). * - * Copyright (c) 2001-2003 Cluster File Systems, Inc. + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf * - * This file is part of Lustre, http://www.lustre.org. + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. * - * Lustre is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public - * License as published by the Free Software Foundation. + * GPL HEADER END + */ +/* + * Copyright 2008 Sun Microsystems, Inc. All rights reserved + * Use is subject to license terms. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. * - * Lustre 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 for more details. + * lustre/llite/rw.c * - * You should have received a copy of the GNU General Public License - * along with Lustre; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * Lustre Lite I/O page cache routines shared by different kernel revs */ -#include +#include #include #include #include @@ -36,15 +53,15 @@ #include #include #include -#include #include #include #include #define DEBUG_SUBSYSTEM S_LLITE -#include -#include +//#include +#include +#include #include "llite_internal.h" #include @@ -54,43 +71,53 @@ pos = n, n = pos->prev ) #endif +cfs_mem_cache_t *ll_async_page_slab = NULL; +size_t ll_async_page_slab_size = 0; + /* SYNCHRONOUS I/O to object storage for an inode */ static int ll_brw(int cmd, struct inode *inode, struct obdo *oa, struct page *page, int flags) { struct ll_inode_info *lli = ll_i2info(inode); struct lov_stripe_md *lsm = lli->lli_smd; + struct obd_info oinfo = { { { 0 } } }; struct brw_page pg; - int rc; + int opc, rc; ENTRY; pg.pg = page; - pg.off = ((obd_off)page->index) << PAGE_SHIFT; + pg.off = ((obd_off)page->index) << CFS_PAGE_SHIFT; - if (cmd == OBD_BRW_WRITE && (pg.off + PAGE_SIZE > inode->i_size)) - pg.count = inode->i_size % PAGE_SIZE; + if ((cmd & OBD_BRW_WRITE) && (pg.off+CFS_PAGE_SIZE>i_size_read(inode))) + pg.count = i_size_read(inode) % CFS_PAGE_SIZE; else - pg.count = PAGE_SIZE; + pg.count = CFS_PAGE_SIZE; - CDEBUG(D_PAGE, "%s %d bytes ino %lu at "LPU64"/"LPX64"\n", - cmd & OBD_BRW_WRITE ? "write" : "read", pg.count, inode->i_ino, - pg.off, pg.off); + LL_CDEBUG_PAGE(D_PAGE, page, "%s %d bytes ino %lu at "LPU64"/"LPX64"\n", + cmd & OBD_BRW_WRITE ? "write" : "read", pg.count, + inode->i_ino, pg.off, pg.off); if (pg.count == 0) { CERROR("ZERO COUNT: ino %lu: size %p:%Lu(%p:%Lu) idx %lu off " - LPU64"\n", - inode->i_ino, inode, inode->i_size, page->mapping->host, - page->mapping->host->i_size, page->index, pg.off); + LPU64"\n", inode->i_ino, inode, i_size_read(inode), + page->mapping->host, i_size_read(page->mapping->host), + page->index, pg.off); } pg.flag = flags; - if (cmd == OBD_BRW_WRITE) - lprocfs_counter_add(ll_i2sbi(inode)->ll_stats, - LPROC_LL_BRW_WRITE, pg.count); + if (cmd & OBD_BRW_WRITE) + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_BRW_WRITE, + pg.count); else - lprocfs_counter_add(ll_i2sbi(inode)->ll_stats, - LPROC_LL_BRW_READ, pg.count); - rc = obd_brw(cmd, ll_i2obdexp(inode), oa, lsm, 1, &pg, NULL); + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_BRW_READ, + pg.count); + oinfo.oi_oa = oa; + oinfo.oi_md = lsm; + /* NB partial write, so we might not have CAPA_OPC_OSS_READ capa */ + opc = cmd & OBD_BRW_WRITE ? CAPA_OPC_OSS_WRITE : CAPA_OPC_OSS_RW; + oinfo.oi_capa = ll_osscapa_get(inode, opc); + rc = obd_brw(cmd, ll_i2dtexp(inode), &oinfo, 1, &pg, NULL); + capa_put(oinfo.oi_capa); if (rc == 0) obdo_to_inode(inode, oa, OBD_MD_FLBLOCKS); else if (rc != -EIO) @@ -98,89 +125,180 @@ static int ll_brw(int cmd, struct inode *inode, struct obdo *oa, RETURN(rc); } -/* this isn't where truncate starts. roughly: - * sys_truncate->ll_setattr_raw->vmtruncate->ll_truncate - * we grab the lock back in setattr_raw to avoid races. */ -void ll_truncate(struct inode *inode) +int ll_file_punch(struct inode * inode, loff_t new_size, int srvlock) { - struct lov_stripe_md *lsm = ll_i2info(inode)->lli_smd; + struct ll_inode_info *lli = ll_i2info(inode); + struct obd_info oinfo = { { { 0 } } }; struct obdo oa; int rc; + ENTRY; - CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p)\n", inode->i_ino, - inode->i_generation, inode); + CDEBUG(D_INFO, "calling punch for "LPX64" (new size %Lu=%#Lx)\n", + lli->lli_smd->lsm_object_id, i_size_read(inode), i_size_read(inode)); + + oinfo.oi_md = lli->lli_smd; + oinfo.oi_policy.l_extent.start = new_size; + oinfo.oi_policy.l_extent.end = OBD_OBJECT_EOF; + oinfo.oi_oa = &oa; + oa.o_id = lli->lli_smd->lsm_object_id; + oa.o_gr = lli->lli_smd->lsm_object_gr; + oa.o_valid = OBD_MD_FLID | OBD_MD_FLGROUP; + if (srvlock) { + /* set OBD_MD_FLFLAGS in o_valid, only if we + * set OBD_FL_TRUNCLOCK, otherwise ost_punch + * and filter_setattr get confused, see the comment + * in ost_punch */ + oa.o_flags = OBD_FL_TRUNCLOCK; + oa.o_valid |= OBD_MD_FLFLAGS; + } + obdo_from_inode(&oa, inode, OBD_MD_FLTYPE | OBD_MD_FLMODE | + OBD_MD_FLATIME | OBD_MD_FLMTIME | OBD_MD_FLCTIME | + OBD_MD_FLFID | OBD_MD_FLGENER); - if (!lsm) { - CDEBUG(D_INODE, "truncate on inode %lu with no objects\n", - inode->i_ino); + oinfo.oi_capa = ll_osscapa_get(inode, CAPA_OPC_OSS_TRUNC); + rc = obd_punch_rqset(ll_i2dtexp(inode), &oinfo, NULL); + ll_truncate_free_capa(oinfo.oi_capa); + if (rc) + CERROR("obd_truncate fails (%d) ino %lu\n", rc, inode->i_ino); + else + obdo_to_inode(inode, &oa, OBD_MD_FLSIZE | OBD_MD_FLBLOCKS | + OBD_MD_FLATIME | OBD_MD_FLMTIME | OBD_MD_FLCTIME); + RETURN(rc); +} + +/* this isn't where truncate starts. roughly: + * sys_truncate->ll_setattr_raw->vmtruncate->ll_truncate. setattr_raw grabs + * DLM lock on [size, EOF], i_mutex, ->lli_size_sem, and WRITE_I_ALLOC_SEM to + * avoid races. + * + * must be called under ->lli_size_sem */ +void ll_truncate(struct inode *inode) +{ + struct ll_inode_info *lli = ll_i2info(inode); + int srvlock = !!(lli->lli_flags & LLIF_SRVLOCK); + loff_t new_size; + ENTRY; + CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p) to %Lu=%#Lx\n",inode->i_ino, + inode->i_generation, inode, i_size_read(inode), + i_size_read(inode)); + + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_TRUNC, 1); + if (lli->lli_size_sem_owner != current) { EXIT; return; } - oa.o_id = lsm->lsm_object_id; - oa.o_gr = lsm->lsm_object_gr; - oa.o_valid = OBD_MD_FLID | OBD_MD_FLGROUP; - obdo_from_inode(&oa, inode, OBD_MD_FLTYPE|OBD_MD_FLMODE|OBD_MD_FLATIME| - OBD_MD_FLMTIME | OBD_MD_FLCTIME); + if (!lli->lli_smd) { + CDEBUG(D_INODE, "truncate on inode %lu with no objects\n", + inode->i_ino); + GOTO(out_unlock, 0); + } - CDEBUG(D_INFO, "calling punch for "LPX64" (all bytes after %Lu)\n", - oa.o_id, inode->i_size); + LASSERT(atomic_read(&lli->lli_size_sem.count) <= 0); + + if (!srvlock) { + struct ost_lvb lvb; + int rc; + + /* XXX I'm pretty sure this is a hack to paper + * over a more fundamental race condition. */ + lov_stripe_lock(lli->lli_smd); + inode_init_lvb(inode, &lvb); + rc = obd_merge_lvb(ll_i2dtexp(inode), lli->lli_smd, &lvb, 0); + if (lvb.lvb_size == i_size_read(inode) && rc == 0) { + CDEBUG(D_VFSTRACE, "skipping punch for obj "LPX64 + ",%Lu=%#Lx\n", lli->lli_smd->lsm_object_id, + i_size_read(inode), i_size_read(inode)); + lov_stripe_unlock(lli->lli_smd); + GOTO(out_unlock, 0); + } + obd_adjust_kms(ll_i2dtexp(inode), lli->lli_smd, + i_size_read(inode), 1); + lov_stripe_unlock(lli->lli_smd); + } - /* truncate == punch from new size to absolute end of file */ - /* NB: obd_punch must be called with i_sem held! It updates the kms! */ - rc = obd_punch(ll_i2obdexp(inode), &oa, lsm, inode->i_size, - OBD_OBJECT_EOF, NULL); - if (rc) - CERROR("obd_truncate fails (%d) ino %lu\n", rc, inode->i_ino); + if (unlikely((ll_i2sbi(inode)->ll_flags & LL_SBI_CHECKSUM) && + (i_size_read(inode) & ~CFS_PAGE_MASK))) { + /* If the truncate leaves behind a partial page, update its + * checksum. */ + struct page *page = find_get_page(inode->i_mapping, + i_size_read(inode) >> + CFS_PAGE_SHIFT); + if (page != NULL) { + struct ll_async_page *llap = llap_cast_private(page); + if (llap != NULL) { + char *kaddr = kmap_atomic(page, KM_USER0); + llap->llap_checksum = + init_checksum(OSC_DEFAULT_CKSUM); + llap->llap_checksum = + compute_checksum(llap->llap_checksum, + kaddr, CFS_PAGE_SIZE, + OSC_DEFAULT_CKSUM); + kunmap_atomic(kaddr, KM_USER0); + } + page_cache_release(page); + } + } + + new_size = i_size_read(inode); + ll_inode_size_unlock(inode, 0); + if (!srvlock) + ll_file_punch(inode, new_size, 0); else - obdo_to_inode(inode, &oa, OBD_MD_FLSIZE | OBD_MD_FLBLOCKS | - OBD_MD_FLATIME | OBD_MD_FLMTIME | - OBD_MD_FLCTIME); + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_LOCKLESS_TRUNC, 1); EXIT; return; + + out_unlock: + ll_inode_size_unlock(inode, 0); } /* ll_truncate */ -__u64 lov_merge_size(struct lov_stripe_md *lsm, int kms); int ll_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) { struct inode *inode = page->mapping->host; struct ll_inode_info *lli = ll_i2info(inode); struct lov_stripe_md *lsm = lli->lli_smd; - obd_off offset = ((obd_off)page->index) << PAGE_SHIFT; + obd_off offset = ((obd_off)page->index) << CFS_PAGE_SHIFT; + struct obd_info oinfo = { { { 0 } } }; struct brw_page pga; struct obdo oa; - __u64 kms; + struct ost_lvb lvb; int rc = 0; ENTRY; - if (!PageLocked(page)) - LBUG(); + LASSERT(PageLocked(page)); + (void)llap_cast_private(page); /* assertion */ /* Check to see if we should return -EIO right away */ pga.pg = page; pga.off = offset; - pga.count = PAGE_SIZE; + pga.count = CFS_PAGE_SIZE; pga.flag = 0; + oa.o_mode = inode->i_mode; oa.o_id = lsm->lsm_object_id; oa.o_gr = lsm->lsm_object_gr; - oa.o_mode = inode->i_mode; - oa.o_valid = OBD_MD_FLID | OBD_MD_FLMODE - | OBD_MD_FLTYPE | OBD_MD_FLGROUP; + oa.o_valid = OBD_MD_FLID | OBD_MD_FLMODE | + OBD_MD_FLTYPE | OBD_MD_FLGROUP; + obdo_from_inode(&oa, inode, OBD_MD_FLFID | OBD_MD_FLGENER); - rc = obd_brw(OBD_BRW_CHECK, ll_i2obdexp(inode), &oa, lsm, 1, &pga, - NULL); + oinfo.oi_oa = &oa; + oinfo.oi_md = lsm; + rc = obd_brw(OBD_BRW_CHECK, ll_i2dtexp(inode), &oinfo, 1, &pga, NULL); if (rc) RETURN(rc); - if (PageUptodate(page)) + if (PageUptodate(page)) { + LL_CDEBUG_PAGE(D_PAGE, page, "uptodate\n"); RETURN(0); + } /* We're completely overwriting an existing page, so _don't_ set it up * to date until commit_write */ - if (from == 0 && to == PAGE_SIZE) { + if (from == 0 && to == CFS_PAGE_SIZE) { + LL_CDEBUG_PAGE(D_PAGE, page, "full page write\n"); POISON_PAGE(page, 0x11); RETURN(0); } @@ -188,10 +306,16 @@ int ll_prepare_write(struct file *file, struct page *page, unsigned from, /* If are writing to a new page, no need to read old data. The extent * locking will have updated the KMS, and for our purposes here we can * treat it like i_size. */ - kms = lov_merge_size(lsm, 1); - if (kms <= offset) { - memset(kmap(page), 0, PAGE_SIZE); - kunmap(page); + lov_stripe_lock(lsm); + inode_init_lvb(inode, &lvb); + obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1); + lov_stripe_unlock(lsm); + if (lvb.lvb_size <= offset) { + char *kaddr = kmap_atomic(page, KM_USER0); + LL_CDEBUG_PAGE(D_PAGE, page, "kms "LPU64" <= offset "LPU64"\n", + lvb.lvb_size, offset); + memset(kaddr, 0, CFS_PAGE_SIZE); + kunmap_atomic(kaddr, KM_USER0); GOTO(prepare_done, rc = 0); } @@ -211,50 +335,30 @@ int ll_prepare_write(struct file *file, struct page *page, unsigned from, return rc; } -int ll_write_count(struct page *page) -{ - struct inode *inode = page->mapping->host; - - /* catch race with truncate */ - if (((loff_t)page->index << PAGE_SHIFT) >= inode->i_size) - return 0; - - /* catch sub-page write at end of file */ - if (((loff_t)page->index << PAGE_SHIFT) + PAGE_SIZE > inode->i_size) - return inode->i_size % PAGE_SIZE; - - return PAGE_SIZE; -} - -struct ll_async_page *llap_from_cookie(void *cookie) -{ - struct ll_async_page *llap = cookie; - if (llap->llap_magic != LLAP_MAGIC) - return ERR_PTR(-EINVAL); - return llap; -}; - +/** + * make page ready for ASYNC write + * \param data - pointer to llap cookie + * \param cmd - is OBD_BRW_* macroses + * + * \retval 0 is page successfully prepared to send + * \retval -EAGAIN is page not need to send + */ static int ll_ap_make_ready(void *data, int cmd) { struct ll_async_page *llap; struct page *page; ENTRY; - llap = llap_from_cookie(data); - if (IS_ERR(llap)) - RETURN(-EINVAL); - + llap = LLAP_FROM_COOKIE(data); page = llap->llap_page; - if (cmd == OBD_BRW_READ) - RETURN(0); - /* we're trying to write, but the page is locked.. come back later */ if (TryLockPage(page)) RETURN(-EAGAIN); - LL_CDEBUG_PAGE(D_PAGE, page, "made ready\n"); - page_cache_get(page); + LASSERTF(!(cmd & OBD_BRW_READ) || !PageWriteback(page), + "cmd %x page %p ino %lu index %lu fl %lx\n", cmd, page, + page->mapping->host->i_ino, page->index, page->flags); /* if we left PageDirty we might get another writepage call * in the future. list walkers are bright enough @@ -263,23 +367,72 @@ static int ll_ap_make_ready(void *data, int cmd) * we got the page cache list we'd create a lock inversion * with the removepage path which gets the page lock then the * cli lock */ - clear_page_dirty(page); + LASSERTF(!PageWriteback(page),"cmd %x page %p ino %lu index %lu\n", cmd, page, + page->mapping->host->i_ino, page->index); + if(!clear_page_dirty_for_io(page)) { + unlock_page(page); + RETURN(-EAGAIN); + } + + /* This actually clears the dirty bit in the radix tree.*/ + set_page_writeback(page); + + LL_CDEBUG_PAGE(D_PAGE, page, "made ready\n"); + page_cache_get(page); + RETURN(0); } +/* We have two reasons for giving llite the opportunity to change the + * write length of a given queued page as it builds the RPC containing + * the page: + * + * 1) Further extending writes may have landed in the page cache + * since a partial write first queued this page requiring us + * to write more from the page cache. (No further races are possible, since + * by the time this is called, the page is locked.) + * 2) We might have raced with truncate and want to avoid performing + * write RPCs that are just going to be thrown away by the + * truncate's punch on the storage targets. + * + * The kms serves these purposes as it is set at both truncate and extending + * writes. + */ static int ll_ap_refresh_count(void *data, int cmd) { + struct ll_inode_info *lli; struct ll_async_page *llap; + struct lov_stripe_md *lsm; + struct page *page; + struct inode *inode; + struct ost_lvb lvb; + __u64 kms; ENTRY; /* readpage queues with _COUNT_STABLE, shouldn't get here. */ LASSERT(cmd != OBD_BRW_READ); - llap = llap_from_cookie(data); - if (IS_ERR(llap)) - RETURN(PTR_ERR(llap)); + llap = LLAP_FROM_COOKIE(data); + page = llap->llap_page; + inode = page->mapping->host; + lli = ll_i2info(inode); + lsm = lli->lli_smd; + + lov_stripe_lock(lsm); + inode_init_lvb(inode, &lvb); + obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1); + kms = lvb.lvb_size; + lov_stripe_unlock(lsm); + + /* catch race with truncate */ + if (((__u64)page->index << CFS_PAGE_SHIFT) >= kms) + return 0; + + /* catch sub-page write at end of file */ + if (((__u64)page->index << CFS_PAGE_SHIFT) + CFS_PAGE_SIZE > kms) + return kms % CFS_PAGE_SIZE; - return ll_write_count(llap->llap_page); + return CFS_PAGE_SIZE; } void ll_inode_fill_obdo(struct inode *inode, int cmd, struct obdo *oa) @@ -293,13 +446,13 @@ void ll_inode_fill_obdo(struct inode *inode, int cmd, struct obdo *oa) oa->o_gr = lsm->lsm_object_gr; oa->o_valid = OBD_MD_FLID | OBD_MD_FLGROUP; valid_flags = OBD_MD_FLTYPE | OBD_MD_FLATIME; - if (cmd == OBD_BRW_WRITE) { - oa->o_valid |= OBD_MD_FLIFID | OBD_MD_FLEPOCH; - mdc_pack_fid(obdo_fid(oa), inode->i_ino, 0, inode->i_mode); - obdo_fid(oa)->mds = ll_i2info(inode)->lli_mds; - oa->o_easize = ll_i2info(inode)->lli_io_epoch; + if (cmd & OBD_BRW_WRITE) { + oa->o_valid |= OBD_MD_FLEPOCH; + oa->o_easize = ll_i2info(inode)->lli_ioepoch; - valid_flags |= OBD_MD_FLMTIME | OBD_MD_FLCTIME; + valid_flags |= OBD_MD_FLMTIME | OBD_MD_FLCTIME | + OBD_MD_FLUID | OBD_MD_FLGID | + OBD_MD_FLFID | OBD_MD_FLGENER; } obdo_from_inode(oa, inode, valid_flags); @@ -310,72 +463,535 @@ static void ll_ap_fill_obdo(void *data, int cmd, struct obdo *oa) struct ll_async_page *llap; ENTRY; - llap = llap_from_cookie(data); - if (IS_ERR(llap)) { - EXIT; - return; - } - + llap = LLAP_FROM_COOKIE(data); ll_inode_fill_obdo(llap->llap_page->mapping->host, cmd, oa); + + EXIT; +} + +static void ll_ap_update_obdo(void *data, int cmd, struct obdo *oa, + obd_valid valid) +{ + struct ll_async_page *llap; + ENTRY; + + llap = LLAP_FROM_COOKIE(data); + obdo_from_inode(oa, llap->llap_page->mapping->host, valid); + EXIT; } +static struct obd_capa *ll_ap_lookup_capa(void *data, int cmd) +{ + struct ll_async_page *llap = LLAP_FROM_COOKIE(data); + int opc = cmd & OBD_BRW_WRITE ? CAPA_OPC_OSS_WRITE : CAPA_OPC_OSS_RW; + + return ll_osscapa_get(llap->llap_page->mapping->host, opc); +} + static struct obd_async_page_ops ll_async_page_ops = { .ap_make_ready = ll_ap_make_ready, .ap_refresh_count = ll_ap_refresh_count, .ap_fill_obdo = ll_ap_fill_obdo, + .ap_update_obdo = ll_ap_update_obdo, .ap_completion = ll_ap_completion, + .ap_lookup_capa = ll_ap_lookup_capa, }; -/* XXX have the exp be an argument? */ -struct ll_async_page *llap_from_page(struct page *page) +struct ll_async_page *llap_cast_private(struct page *page) +{ + struct ll_async_page *llap = (struct ll_async_page *)page_private(page); + + LASSERTF(llap == NULL || llap->llap_magic == LLAP_MAGIC, + "page %p private %lu gave magic %d which != %d\n", + page, page_private(page), llap->llap_magic, LLAP_MAGIC); + + return llap; +} + +/* Try to reap @target pages in the specific @cpu's async page list. + * + * There is an llap attached onto every page in lustre, linked off @sbi. + * We add an llap to the list so we don't lose our place during list walking. + * If llaps in the list are being moved they will only move to the end + * of the LRU, and we aren't terribly interested in those pages here (we + * start at the beginning of the list where the least-used llaps are. */ +static inline int llap_shrink_cache_internal(struct ll_sb_info *sbi, + int cpu, int target) +{ + struct ll_async_page *llap, dummy_llap = { .llap_magic = 0xd11ad11a }; + struct ll_pglist_data *pd; + struct list_head *head; + int count = 0; + + pd = ll_pglist_cpu_lock(sbi, cpu); + head = &pd->llpd_list; + list_add(&dummy_llap.llap_pglist_item, head); + while (count < target) { + struct page *page; + int keep; + + if (unlikely(need_resched())) { + ll_pglist_cpu_unlock(sbi, cpu); + cond_resched(); + ll_pglist_cpu_lock(sbi, cpu); + } + + llap = llite_pglist_next_llap(head, + &dummy_llap.llap_pglist_item); + list_del_init(&dummy_llap.llap_pglist_item); + if (llap == NULL) + break; + + page = llap->llap_page; + LASSERT(page != NULL); + + list_add(&dummy_llap.llap_pglist_item, &llap->llap_pglist_item); + + /* Page needs/undergoing IO */ + if (TryLockPage(page)) { + LL_CDEBUG_PAGE(D_PAGE, page, "can't lock\n"); + continue; + } + + keep = (llap->llap_write_queued || PageDirty(page) || + PageWriteback(page) || (!PageUptodate(page) && + llap->llap_origin != LLAP_ORIGIN_READAHEAD)); + + LL_CDEBUG_PAGE(D_PAGE, page,"%s LRU page: %s%s%s%s%s origin %s\n", + keep ? "keep" : "drop", + llap->llap_write_queued ? "wq " : "", + PageDirty(page) ? "pd " : "", + PageUptodate(page) ? "" : "!pu ", + PageWriteback(page) ? "wb" : "", + llap->llap_defer_uptodate ? "" : "!du", + llap_origins[llap->llap_origin]); + + /* If page is dirty or undergoing IO don't discard it */ + if (keep) { + unlock_page(page); + continue; + } + + page_cache_get(page); + ll_pglist_cpu_unlock(sbi, cpu); + + if (page->mapping != NULL) { + ll_teardown_mmaps(page->mapping, + (__u64)page->index << CFS_PAGE_SHIFT, + ((__u64)page->index << CFS_PAGE_SHIFT)| + ~CFS_PAGE_MASK); + if (!PageDirty(page) && !page_mapped(page)) { + ll_ra_accounting(llap, page->mapping); + ll_truncate_complete_page(page); + ++count; + } else { + LL_CDEBUG_PAGE(D_PAGE, page, "Not dropping page" + " because it is " + "%s\n", + PageDirty(page)? + "dirty":"mapped"); + } + } + unlock_page(page); + page_cache_release(page); + + ll_pglist_cpu_lock(sbi, cpu); + } + list_del(&dummy_llap.llap_pglist_item); + ll_pglist_cpu_unlock(sbi, cpu); + + CDEBUG(D_CACHE, "shrank %d, expected %d however. \n", count, target); + return count; +} + + +/* Try to shrink the page cache for the @sbi filesystem by 1/@shrink_fraction. + * + * At first, this code calculates total pages wanted by @shrink_fraction, then + * it deduces how many pages should be reaped from each cpu in proportion as + * their own # of page count(llpd_count). + */ +int llap_shrink_cache(struct ll_sb_info *sbi, int shrink_fraction) +{ + unsigned long total, want, percpu_want, count = 0; + int cpu, nr_cpus; + + total = lcounter_read(&sbi->ll_async_page_count); + if (total == 0) + return 0; + +#ifdef HAVE_SHRINKER_CACHE + want = shrink_fraction; + if (want == 0) + return total; +#else + /* There can be a large number of llaps (600k or more in a large + * memory machine) so the VM 1/6 shrink ratio is likely too much. + * Since we are freeing pages also, we don't necessarily want to + * shrink so much. Limit to 40MB of pages + llaps per call. */ + if (shrink_fraction <= 0) + want = total - sbi->ll_async_page_max + 32*num_online_cpus(); + else + want = (total + shrink_fraction - 1) / shrink_fraction; +#endif + + if (want > 40 << (20 - CFS_PAGE_SHIFT)) + want = 40 << (20 - CFS_PAGE_SHIFT); + + CDEBUG(D_CACHE, "shrinking %lu of %lu pages (1/%d)\n", + want, total, shrink_fraction); + + nr_cpus = num_possible_cpus(); + cpu = sbi->ll_async_page_clock_hand; + /* we at most do one round */ + do { + int c; + + cpu = (cpu + 1) % nr_cpus; + c = LL_PGLIST_DATA_CPU(sbi, cpu)->llpd_count; + if (!cpu_online(cpu)) + percpu_want = c; + else + percpu_want = want / ((total / (c + 1)) + 1); + if (percpu_want == 0) + continue; + + count += llap_shrink_cache_internal(sbi, cpu, percpu_want); + if (count >= want) + sbi->ll_async_page_clock_hand = cpu; + } while (cpu != sbi->ll_async_page_clock_hand); + + CDEBUG(D_CACHE, "shrank %lu/%lu and left %lu unscanned\n", + count, want, total); + +#ifdef HAVE_SHRINKER_CACHE + return lcounter_read(&sbi->ll_async_page_count); +#else + return count; +#endif +} + +/* Rebalance the async page queue len for each cpu. We hope that the cpu + * which do much IO job has a relative longer queue len. + * This function should be called with preempt disabled. + */ +static inline int llap_async_cache_rebalance(struct ll_sb_info *sbi) +{ + unsigned long sample = 0, *cpu_sample, bias, slice; + struct ll_pglist_data *pd; + cpumask_t mask; + int cpu, surplus; + int w1 = 7, w2 = 3, base = (w1 + w2); /* weight value */ + atomic_t *pcnt; + + if (!spin_trylock(&sbi->ll_async_page_reblnc_lock)) { + /* someone else is doing the job */ + return 1; + } + + pcnt = &LL_PGLIST_DATA(sbi)->llpd_sample_count; + if (!atomic_read(pcnt)) { + /* rare case, somebody else has gotten this job done */ + spin_unlock(&sbi->ll_async_page_reblnc_lock); + return 1; + } + + sbi->ll_async_page_reblnc_count++; + cpu_sample = sbi->ll_async_page_sample; + memset(cpu_sample, 0, num_possible_cpus() * sizeof(unsigned long)); + for_each_online_cpu(cpu) { + pcnt = &LL_PGLIST_DATA_CPU(sbi, cpu)->llpd_sample_count; + cpu_sample[cpu] = atomic_read(pcnt); + atomic_set(pcnt, 0); + sample += cpu_sample[cpu]; + } + + cpus_clear(mask); + surplus = sbi->ll_async_page_max; + slice = surplus / sample + 1; + sample /= num_online_cpus(); + bias = sample >> 4; + for_each_online_cpu(cpu) { + pd = LL_PGLIST_DATA_CPU(sbi, cpu); + if (labs((long int)sample - cpu_sample[cpu]) > bias) { + unsigned long budget = pd->llpd_budget; + /* weighted original queue length and expected queue + * length to avoid thrashing. */ + pd->llpd_budget = (budget * w1) / base + + (slice * cpu_sample[cpu]) * w2 / base; + cpu_set(cpu, mask); + } + surplus -= pd->llpd_budget; + } + surplus /= cpus_weight(mask) ?: 1; + for_each_cpu_mask(cpu, mask) + LL_PGLIST_DATA_CPU(sbi, cpu)->llpd_budget += surplus; + spin_unlock(&sbi->ll_async_page_reblnc_lock); + + /* TODO: do we really need to call llap_shrink_cache_internal + * for every cpus with its page_count greater than budget? + * for_each_cpu_mask(cpu, mask) + * ll_shrink_cache_internal(...) + */ + + return 0; +} + +static struct ll_async_page *llap_from_page_with_lockh(struct page *page, + unsigned origin, + struct lustre_handle *lockh) { struct ll_async_page *llap; struct obd_export *exp; struct inode *inode = page->mapping->host; - struct ll_sb_info *sbi = ll_i2sbi(inode); - int rc; + struct ll_sb_info *sbi; + struct ll_pglist_data *pd; + int rc, cpu, target; ENTRY; - llap = (struct ll_async_page *)page->private; + if (!inode) { + static int triggered; + + if (!triggered) { + LL_CDEBUG_PAGE(D_ERROR, page, "Bug 10047. Wrong anon " + "page received\n"); + libcfs_debug_dumpstack(NULL); + triggered = 1; + } + RETURN(ERR_PTR(-EINVAL)); + } + sbi = ll_i2sbi(inode); + LASSERT(ll_async_page_slab); + LASSERTF(origin < LLAP__ORIGIN_MAX, "%u\n", origin); + + llap = llap_cast_private(page); if (llap != NULL) { - if (llap->llap_magic != LLAP_MAGIC) - RETURN(ERR_PTR(-EINVAL)); - RETURN(llap); + /* move to end of LRU list, except when page is just about to + * die */ + if (origin != LLAP_ORIGIN_REMOVEPAGE) { + int old_cpu = llap->llap_pglist_cpu; + struct ll_pglist_data *old_pd; + + pd = ll_pglist_double_lock(sbi, old_cpu, &old_pd); + pd->llpd_hit++; + while (old_cpu != llap->llap_pglist_cpu) { + /* rarely case, someone else is touching this + * page too. */ + ll_pglist_double_unlock(sbi, old_cpu); + old_cpu = llap->llap_pglist_cpu; + pd=ll_pglist_double_lock(sbi, old_cpu, &old_pd); + } + + list_move(&llap->llap_pglist_item, + &pd->llpd_list); + old_pd->llpd_gen++; + if (pd->llpd_cpu != old_cpu) { + pd->llpd_count++; + old_pd->llpd_count--; + old_pd->llpd_gen++; + llap->llap_pglist_cpu = pd->llpd_cpu; + pd->llpd_cross++; + } + ll_pglist_double_unlock(sbi, old_cpu); + } + GOTO(out, llap); } - exp = ll_i2obdexp(page->mapping->host); + exp = ll_i2dtexp(page->mapping->host); if (exp == NULL) RETURN(ERR_PTR(-EINVAL)); - OBD_ALLOC(llap, sizeof(*llap)); + /* limit the number of lustre-cached pages */ + cpu = get_cpu(); + pd = LL_PGLIST_DATA(sbi); + target = pd->llpd_count - pd->llpd_budget; + if (target > 0) { + rc = 0; + atomic_inc(&pd->llpd_sample_count); + if (atomic_read(&pd->llpd_sample_count) > + sbi->ll_async_page_sample_max) { + pd->llpd_reblnc_count++; + rc = llap_async_cache_rebalance(sbi); + if (rc == 0) + target = pd->llpd_count - pd->llpd_budget; + } + /* if rc equals 1, it means other cpu is doing the rebalance + * job, and our budget # would be modified when we read it. + * Furthermore, it is much likely being increased because + * we have already reached the rebalance threshold. In this + * case, we skip to shrink cache here. */ + if ((rc == 0) && target > 0) + llap_shrink_cache_internal(sbi, cpu, target + 32); + } + put_cpu(); + + OBD_SLAB_ALLOC(llap, ll_async_page_slab, CFS_ALLOC_STD, + ll_async_page_slab_size); if (llap == NULL) RETURN(ERR_PTR(-ENOMEM)); llap->llap_magic = LLAP_MAGIC; + llap->llap_cookie = (void *)llap + size_round(sizeof(*llap)); + + /* XXX: for bug 11270 - check for lockless origin here! */ + if (origin == LLAP_ORIGIN_LOCKLESS_IO) + llap->llap_nocache = 1; + rc = obd_prep_async_page(exp, ll_i2info(inode)->lli_smd, NULL, page, - (obd_off)page->index << PAGE_SHIFT, - &ll_async_page_ops, llap, &llap->llap_cookie); + (obd_off)page->index << CFS_PAGE_SHIFT, + &ll_async_page_ops, llap, &llap->llap_cookie, + llap->llap_nocache, lockh); if (rc) { - OBD_FREE(llap, sizeof(*llap)); + OBD_SLAB_FREE(llap, ll_async_page_slab, + ll_async_page_slab_size); RETURN(ERR_PTR(rc)); } CDEBUG(D_CACHE, "llap %p page %p cookie %p obj off "LPU64"\n", llap, - page, llap->llap_cookie, (obd_off)page->index << PAGE_SHIFT); + page, llap->llap_cookie, (obd_off)page->index << CFS_PAGE_SHIFT); /* also zeroing the PRIVBITS low order bitflags */ - page->private = (unsigned long)llap; + __set_page_ll_data(page, llap); llap->llap_page = page; - spin_lock(&sbi->ll_pglist_lock); - sbi->ll_pglist_gen++; - list_add_tail(&llap->llap_proc_item, &sbi->ll_pglist); - spin_unlock(&sbi->ll_pglist_lock); + lcounter_inc(&sbi->ll_async_page_count); + pd = ll_pglist_lock(sbi); + list_add_tail(&llap->llap_pglist_item, &pd->llpd_list); + INIT_LIST_HEAD(&llap->llap_pending_write); + pd->llpd_count++; + pd->llpd_gen++; + pd->llpd_miss++; + llap->llap_pglist_cpu = pd->llpd_cpu; + ll_pglist_unlock(sbi); + + out: + if (unlikely(sbi->ll_flags & LL_SBI_CHECKSUM)) { + __u32 csum; + char *kaddr = kmap_atomic(page, KM_USER0); + csum = init_checksum(OSC_DEFAULT_CKSUM); + csum = compute_checksum(csum, kaddr, CFS_PAGE_SIZE, + OSC_DEFAULT_CKSUM); + kunmap_atomic(kaddr, KM_USER0); + if (origin == LLAP_ORIGIN_READAHEAD || + origin == LLAP_ORIGIN_READPAGE || + origin == LLAP_ORIGIN_LOCKLESS_IO) { + llap->llap_checksum = 0; + } else if (origin == LLAP_ORIGIN_COMMIT_WRITE || + llap->llap_checksum == 0) { + llap->llap_checksum = csum; + CDEBUG(D_PAGE, "page %p cksum %x\n", page, csum); + } else if (llap->llap_checksum == csum) { + /* origin == LLAP_ORIGIN_WRITEPAGE */ + CDEBUG(D_PAGE, "page %p cksum %x confirmed\n", + page, csum); + } else { + /* origin == LLAP_ORIGIN_WRITEPAGE */ + LL_CDEBUG_PAGE(D_ERROR, page, "old cksum %x != new " + "%x!\n", llap->llap_checksum, csum); + } + } + llap->llap_origin = origin; RETURN(llap); } -void lov_increase_kms(struct obd_export *exp, struct lov_stripe_md *lsm, - obd_off size); +struct ll_async_page *llap_from_page(struct page *page, + unsigned origin) +{ + return llap_from_page_with_lockh(page, origin, NULL); +} + +static int queue_or_sync_write(struct obd_export *exp, struct inode *inode, + struct ll_async_page *llap, + unsigned to, obd_flag async_flags) +{ + unsigned long size_index = i_size_read(inode) >> CFS_PAGE_SHIFT; + struct obd_io_group *oig; + struct ll_sb_info *sbi = ll_i2sbi(inode); + int rc, noquot = llap->llap_ignore_quota ? OBD_BRW_NOQUOTA : 0; + ENTRY; + + /* _make_ready only sees llap once we've unlocked the page */ + llap->llap_write_queued = 1; + rc = obd_queue_async_io(exp, ll_i2info(inode)->lli_smd, NULL, + llap->llap_cookie, OBD_BRW_WRITE | noquot, + 0, 0, 0, async_flags); + if (rc == 0) { + LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, "write queued\n"); + GOTO(out, 0); + } + + llap->llap_write_queued = 0; + /* Do not pass llap here as it is sync write. */ + llap_write_pending(inode, NULL); + + rc = oig_init(&oig); + if (rc) + GOTO(out, rc); + + /* make full-page requests if we are not at EOF (bug 4410) */ + if (to != CFS_PAGE_SIZE && llap->llap_page->index < size_index) { + LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, + "sync write before EOF: size_index %lu, to %d\n", + size_index, to); + to = CFS_PAGE_SIZE; + } else if (to != CFS_PAGE_SIZE && llap->llap_page->index == size_index) { + int size_to = i_size_read(inode) & ~CFS_PAGE_MASK; + LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, + "sync write at EOF: size_index %lu, to %d/%d\n", + size_index, to, size_to); + if (to < size_to) + to = size_to; + } + + /* compare the checksum once before the page leaves llite */ + if (unlikely((sbi->ll_flags & LL_SBI_CHECKSUM) && + llap->llap_checksum != 0)) { + __u32 csum; + struct page *page = llap->llap_page; + char *kaddr = kmap_atomic(page, KM_USER0); + csum = init_checksum(OSC_DEFAULT_CKSUM); + csum = compute_checksum(csum, kaddr, CFS_PAGE_SIZE, + OSC_DEFAULT_CKSUM); + kunmap_atomic(kaddr, KM_USER0); + if (llap->llap_checksum == csum) { + CDEBUG(D_PAGE, "page %p cksum %x confirmed\n", + page, csum); + } else { + CERROR("page %p old cksum %x != new cksum %x!\n", + page, llap->llap_checksum, csum); + } + } + + rc = obd_queue_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig, + llap->llap_cookie, OBD_BRW_WRITE | noquot, + 0, to, 0, ASYNC_READY | ASYNC_URGENT | + ASYNC_COUNT_STABLE | ASYNC_GROUP_SYNC); + if (rc) + GOTO(free_oig, rc); + + rc = obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig); + if (rc) + GOTO(free_oig, rc); + + rc = oig_wait(oig); + + if (!rc && async_flags & ASYNC_READY) { + unlock_page(llap->llap_page); + if (PageWriteback(llap->llap_page)) + end_page_writeback(llap->llap_page); + } + + if (rc == 0 && llap_write_complete(inode, llap)) + ll_queue_done_writing(inode, 0); + + LL_CDEBUG_PAGE(D_PAGE, llap->llap_page, "sync write returned %d\n", rc); + +free_oig: + oig_release(oig); +out: + RETURN(rc); +} + /* update our write count to account for i_size increases that may have * happened since we've queued the page for io. */ @@ -384,12 +1000,14 @@ void lov_increase_kms(struct obd_export *exp, struct lov_stripe_md *lsm, int ll_commit_write(struct file *file, struct page *page, unsigned from, unsigned to) { + struct ll_file_data *fd = LUSTRE_FPRIVATE(file); struct inode *inode = page->mapping->host; struct ll_inode_info *lli = ll_i2info(inode); struct lov_stripe_md *lsm = lli->lli_smd; - struct obd_export *exp = NULL; + struct obd_export *exp; struct ll_async_page *llap; loff_t size; + struct lustre_handle *lockh = NULL; int rc = 0; ENTRY; @@ -400,104 +1018,189 @@ int ll_commit_write(struct file *file, struct page *page, unsigned from, CDEBUG(D_INODE, "inode %p is writing page %p from %d to %d at %lu\n", inode, page, from, to, page->index); - llap = llap_from_page(page); + if (fd->fd_flags & LL_FILE_GROUP_LOCKED) + lockh = &fd->fd_cwlockh; + + llap = llap_from_page_with_lockh(page, LLAP_ORIGIN_COMMIT_WRITE, lockh); if (IS_ERR(llap)) RETURN(PTR_ERR(llap)); - /* queue a write for some time in the future the first time we - * dirty the page */ - if (!PageDirty(page)) { - lprocfs_counter_incr(ll_i2sbi(inode)->ll_stats, - LPROC_LL_DIRTY_MISSES); - - exp = ll_i2obdexp(inode); - if (exp == NULL) - RETURN(-EINVAL); - - /* _make_ready only sees llap once we've unlocked the page */ - llap->llap_write_queued = 1; - rc = obd_queue_async_io(exp, lsm, NULL, llap->llap_cookie, - OBD_BRW_WRITE, 0, 0, 0, 0); - if (rc != 0) { /* async failed, try sync.. */ - struct obd_io_group *oig; - rc = oig_init(&oig); - if (rc) - GOTO(out, rc); - - llap->llap_write_queued = 0; - rc = obd_queue_group_io(exp, lsm, NULL, oig, - llap->llap_cookie, - OBD_BRW_WRITE, 0, to, 0, - ASYNC_READY | ASYNC_URGENT | - ASYNC_COUNT_STABLE | - ASYNC_GROUP_SYNC); - - if (rc) - GOTO(free_oig, rc); + exp = ll_i2dtexp(inode); + if (exp == NULL) + RETURN(-EINVAL); - rc = obd_trigger_group_io(exp, lsm, NULL, oig); - if (rc) - GOTO(free_oig, rc); + llap->llap_ignore_quota = capable(CAP_SYS_RESOURCE); + + /* + * queue a write for some time in the future the first time we + * dirty the page. + * + * This is different from what other file systems do: they usually + * just mark page (and some of its buffers) dirty and rely on + * balance_dirty_pages() to start a write-back. Lustre wants write-back + * to be started earlier for the following reasons: + * + * (1) with a large number of clients we need to limit the amount + * of cached data on the clients a lot; + * + * (2) large compute jobs generally want compute-only then io-only + * and the IO should complete as quickly as possible; + * + * (3) IO is batched up to the RPC size and is async until the + * client max cache is hit + * (/proc/fs/lustre/osc/OSC.../max_dirty_mb) + * + */ + if (!PageDirty(page)) { + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRTY_MISSES, 1); - rc = oig_wait(oig); -free_oig: - oig_release(oig); + rc = queue_or_sync_write(exp, inode, llap, to, 0); + if (rc) GOTO(out, rc); - } - LL_CDEBUG_PAGE(D_PAGE, page, "write queued\n"); - //llap_write_pending(inode, llap); } else { - lprocfs_counter_incr(ll_i2sbi(inode)->ll_stats, - LPROC_LL_DIRTY_HITS); + ll_stats_ops_tally(ll_i2sbi(inode), LPROC_LL_DIRTY_HITS, 1); } /* put the page in the page cache, from now on ll_removepage is - * responsible for cleaning up the llap */ - set_page_dirty(page); + * responsible for cleaning up the llap. + * only set page dirty when it's queued to be write out */ + if (llap->llap_write_queued) + set_page_dirty(page); out: + size = (((obd_off)page->index) << CFS_PAGE_SHIFT) + to; + ll_inode_size_lock(inode, 0); if (rc == 0) { - size = (((obd_off)page->index) << PAGE_SHIFT) + to; - lov_increase_kms(exp, lsm, size); - if (size > inode->i_size) - inode->i_size = size; + lov_stripe_lock(lsm); + obd_adjust_kms(exp, lsm, size, 0); + lov_stripe_unlock(lsm); + if (size > i_size_read(inode)) + i_size_write(inode, size); SetPageUptodate(page); + } else if (size > i_size_read(inode)) { + /* this page beyond the pales of i_size, so it can't be + * truncated in ll_p_r_e during lock revoking. we must + * teardown our book-keeping here. */ + ll_removepage(page); } + ll_inode_size_unlock(inode, 0); RETURN(rc); } -/* the kernel calls us here when a page is unhashed from the page cache. - * the page will be locked and the kernel is holding a spinlock, so - * we need to be careful. we're just tearing down our book-keeping - * here. */ -void ll_removepage(struct page *page) +static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which); + +/* WARNING: This algorithm is used to reduce the contention on + * sbi->ll_lock. It should work well if the ra_max_pages is much + * greater than the single file's read-ahead window. + * + * TODO: There may exist a `global sync problem' in this implementation. + * Considering the global ra window is 100M, and each file's ra window is 10M, + * there are over 10 files trying to get its ra budget and reach + * ll_ra_count_get at the exactly same time. All of them will get a zero ra + * window, although the global window is 100M. -jay + */ +static unsigned long ll_ra_count_get(struct ll_sb_info *sbi, unsigned long len) { - struct inode *inode = page->mapping->host; - struct obd_export *exp; - struct ll_async_page *llap; - struct ll_sb_info *sbi = ll_i2sbi(inode); - int rc; + struct ll_ra_info *ra = &sbi->ll_ra_info; + unsigned long ret; ENTRY; - LASSERT(!in_interrupt()); + ret = min(ra->ra_max_pages - atomic_read(&ra->ra_cur_pages), len); + if ((int)ret < 0) + GOTO(out, ret = 0); - /* sync pages or failed read pages can leave pages in the page - * cache that don't have our data associated with them anymore */ - if (page->private == 0) { - EXIT; - return; + if (atomic_add_return(ret, &ra->ra_cur_pages) > ra->ra_max_pages) { + atomic_sub(ret, &ra->ra_cur_pages); + ret = 0; } +out: + RETURN(ret); +} - LL_CDEBUG_PAGE(D_PAGE, page, "being evicted\n"); - - exp = ll_i2obdexp(inode); +static void ll_ra_count_put(struct ll_sb_info *sbi, unsigned long len) +{ + struct ll_ra_info *ra = &sbi->ll_ra_info; + atomic_sub(len, &ra->ra_cur_pages); +} + +/* called for each page in a completed rpc.*/ +int ll_ap_completion(void *data, int cmd, struct obdo *oa, int rc) +{ + struct ll_async_page *llap; + struct page *page; + int ret = 0; + ENTRY; + + llap = LLAP_FROM_COOKIE(data); + page = llap->llap_page; + LASSERT(PageLocked(page)); + LASSERT(CheckWriteback(page,cmd)); + + LL_CDEBUG_PAGE(D_PAGE, page, "completing cmd %d with %d\n", cmd, rc); + + if (cmd & OBD_BRW_READ && llap->llap_defer_uptodate) + ll_ra_count_put(ll_i2sbi(page->mapping->host), 1); + + if (rc == 0) { + if (cmd & OBD_BRW_READ) { + if (!llap->llap_defer_uptodate) + SetPageUptodate(page); + } else { + llap->llap_write_queued = 0; + } + ClearPageError(page); + } else { + if (cmd & OBD_BRW_READ) { + llap->llap_defer_uptodate = 0; + } + SetPageError(page); + if (rc == -ENOSPC) + set_bit(AS_ENOSPC, &page->mapping->flags); + else + set_bit(AS_EIO, &page->mapping->flags); + } + + /* be carefull about clear WB. + * if WB will cleared after page lock is released - paralel IO can be + * started before ap_make_ready is finished - so we will be have page + * with PG_Writeback set from ->writepage() and completed READ which + * clear this flag */ + if ((cmd & OBD_BRW_WRITE) && PageWriteback(page)) + end_page_writeback(page); + + unlock_page(page); + + if (cmd & OBD_BRW_WRITE) { + /* Only rc == 0, write succeed, then this page could be deleted + * from the pending_writing list + */ + if (rc == 0 && llap_write_complete(page->mapping->host, llap)) + ll_queue_done_writing(page->mapping->host, 0); + } + + page_cache_release(page); + + RETURN(ret); +} + +static void __ll_put_llap(struct page *page) +{ + struct inode *inode = page->mapping->host; + struct obd_export *exp; + struct ll_async_page *llap; + struct ll_sb_info *sbi = ll_i2sbi(inode); + struct ll_pglist_data *pd; + int rc, cpu; + ENTRY; + + exp = ll_i2dtexp(inode); if (exp == NULL) { CERROR("page %p ind %lu gave null export\n", page, page->index); EXIT; return; } - llap = llap_from_page(page); + llap = llap_from_page(page, LLAP_ORIGIN_REMOVEPAGE); if (IS_ERR(llap)) { CERROR("page %p ind %lu couldn't find llap: %ld\n", page, page->index, PTR_ERR(llap)); @@ -505,7 +1208,9 @@ void ll_removepage(struct page *page) return; } - //llap_write_complete(inode, llap); + if (llap_write_complete(inode, llap)) + ll_queue_done_writing(inode, 0); + rc = obd_teardown_async_page(exp, ll_i2info(inode)->lli_smd, NULL, llap->llap_cookie); if (rc != 0) @@ -513,37 +1218,43 @@ void ll_removepage(struct page *page) /* this unconditional free is only safe because the page lock * is providing exclusivity to memory pressure/truncate/writeback..*/ - page->private = 0; - - spin_lock(&sbi->ll_pglist_lock); - if (!list_empty(&llap->llap_proc_item)) - list_del_init(&llap->llap_proc_item); - sbi->ll_pglist_gen++; - spin_unlock(&sbi->ll_pglist_lock); - OBD_FREE(llap, sizeof(*llap)); + __clear_page_ll_data(page); + + lcounter_dec(&sbi->ll_async_page_count); + cpu = llap->llap_pglist_cpu; + pd = ll_pglist_cpu_lock(sbi, cpu); + pd->llpd_gen++; + pd->llpd_count--; + if (!list_empty(&llap->llap_pglist_item)) + list_del_init(&llap->llap_pglist_item); + ll_pglist_cpu_unlock(sbi, cpu); + OBD_SLAB_FREE(llap, ll_async_page_slab, ll_async_page_slab_size); EXIT; } -static int ll_page_matches(struct page *page, int fd_flags) +/* the kernel calls us here when a page is unhashed from the page cache. + * the page will be locked and the kernel is holding a spinlock, so + * we need to be careful. we're just tearing down our book-keeping + * here. */ +void ll_removepage(struct page *page) { - struct lustre_handle match_lockh = {0}; - struct inode *inode = page->mapping->host; - ldlm_policy_data_t page_extent; - int flags, matches; + struct ll_async_page *llap = llap_cast_private(page); ENTRY; - if (fd_flags & LL_FILE_CW_LOCKED) - RETURN(1); + LASSERT(!in_interrupt()); + + /* sync pages or failed read pages can leave pages in the page + * cache that don't have our data associated with them anymore */ + if (page_private(page) == 0) { + EXIT; + return; + } - page_extent.l_extent.start = (__u64)page->index << PAGE_CACHE_SHIFT; - page_extent.l_extent.end = - page_extent.l_extent.start + PAGE_CACHE_SIZE - 1; - flags = LDLM_FL_CBPENDING | LDLM_FL_BLOCK_GRANTED | LDLM_FL_TEST_LOCK; - matches = obd_match(ll_i2sbi(inode)->ll_osc_exp, - ll_i2info(inode)->lli_smd, LDLM_EXTENT, - &page_extent, LCK_PR | LCK_PW, &flags, inode, - &match_lockh); - RETURN(matches); + LASSERT(!llap->llap_lockless_io_page); + LASSERT(!llap->llap_nocache); + LL_CDEBUG_PAGE(D_PAGE, page, "being evicted\n"); + __ll_put_llap(page); + EXIT; } static int ll_issue_page_read(struct obd_export *exp, @@ -555,9 +1266,11 @@ static int ll_issue_page_read(struct obd_export *exp, page_cache_get(page); llap->llap_defer_uptodate = defer; + llap->llap_ra_used = 0; rc = obd_queue_group_io(exp, ll_i2info(page->mapping->host)->lli_smd, NULL, oig, llap->llap_cookie, OBD_BRW_READ, 0, - PAGE_SIZE, 0, ASYNC_COUNT_STABLE); + CFS_PAGE_SIZE, 0, ASYNC_COUNT_STABLE | + ASYNC_READY | ASYNC_URGENT); if (rc) { LL_CDEBUG_PAGE(D_ERROR, page, "read queue failed: rc %d\n", rc); page_cache_release(page); @@ -565,171 +1278,729 @@ static int ll_issue_page_read(struct obd_export *exp, RETURN(rc); } -#define LL_RA_MIN(inode) ((unsigned long)PTLRPC_MAX_BRW_PAGES / 2) -#define LL_RA_MAX(inode) ((ll_i2info(inode)->lli_smd->lsm_xfersize * 3) >> \ - PAGE_CACHE_SHIFT) +static void ll_ra_stats_inc_sbi(struct ll_sb_info *sbi, enum ra_stat which) +{ + LASSERTF(which >= 0 && which < _NR_RA_STAT, "which: %u\n", which); + lprocfs_counter_incr(sbi->ll_ra_stats, which); +} -static void ll_readahead(struct ll_readahead_state *ras, - struct obd_export *exp, struct address_space *mapping, - struct obd_io_group *oig, int flags) +static void ll_ra_stats_inc(struct address_space *mapping, enum ra_stat which) { - unsigned long i, start, end; - struct ll_async_page *llap; - struct page *page; - int rc; + struct ll_sb_info *sbi = ll_i2sbi(mapping->host); + ll_ra_stats_inc_sbi(sbi, which); +} - if (mapping->host->i_size == 0) +void ll_ra_accounting(struct ll_async_page *llap, struct address_space *mapping) +{ + if (!llap->llap_defer_uptodate || llap->llap_ra_used) return; + ll_ra_stats_inc(mapping, RA_STAT_DISCARDED); +} + +#define RAS_CDEBUG(ras) \ + CDEBUG(D_READA, \ + "lrp %lu cr %lu cp %lu ws %lu wl %lu nra %lu r %lu ri %lu" \ + "csr %lu sf %lu sp %lu sl %lu \n", \ + ras->ras_last_readpage, ras->ras_consecutive_requests, \ + ras->ras_consecutive_pages, ras->ras_window_start, \ + ras->ras_window_len, ras->ras_next_readahead, \ + ras->ras_requests, ras->ras_request_index, \ + ras->ras_consecutive_stride_requests, ras->ras_stride_offset, \ + ras->ras_stride_pages, ras->ras_stride_length) + +static int index_in_window(unsigned long index, unsigned long point, + unsigned long before, unsigned long after) +{ + unsigned long start = point - before, end = point + after; + + if (start > point) + start = 0; + if (end < point) + end = ~0; + + return start <= index && index <= end; +} + +static struct ll_readahead_state *ll_ras_get(struct file *f) +{ + struct ll_file_data *fd; + + fd = LUSTRE_FPRIVATE(f); + return &fd->fd_ras; +} + +void ll_ra_read_in(struct file *f, struct ll_ra_read *rar) +{ + struct ll_readahead_state *ras; + + ras = ll_ras_get(f); + spin_lock(&ras->ras_lock); + ras->ras_requests++; + ras->ras_request_index = 0; + ras->ras_consecutive_requests++; + rar->lrr_reader = current; - /* make sure to issue a window's worth of read-ahead pages */ - end = ras->ras_last; - start = end - ras->ras_window; - if (start > end) - start = 0; + list_add(&rar->lrr_linkage, &ras->ras_read_beads); + spin_unlock(&ras->ras_lock); +} - /* but don't iterate over pages that we've already issued. this - * will set start to end + 1 if we've already read-ahead up to - * ras_last sothe for() won't be entered */ - if (ras->ras_next_index > start) - start = ras->ras_next_index; - if (end != ~0UL) - ras->ras_next_index = end + 1; +void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar) +{ + struct ll_readahead_state *ras; - CDEBUG(D_READA, "ni %lu last %lu win %lu: reading from %lu to %lu\n", - ras->ras_next_index, ras->ras_last, ras->ras_window, - start, end); + ras = ll_ras_get(f); + spin_lock(&ras->ras_lock); + list_del_init(&rar->lrr_linkage); spin_unlock(&ras->ras_lock); +} - /* clamp to filesize */ - i = (mapping->host->i_size - 1) >> PAGE_CACHE_SHIFT; - end = min(end, i); +static struct ll_ra_read *ll_ra_read_get_locked(struct ll_readahead_state *ras) +{ + struct ll_ra_read *scan; - for (i = start; i <= end; i++) { - /* grab_cache_page_nowait returns null if this races with - * truncating the page (page->mapping == NULL) */ - page = grab_cache_page_nowait(mapping, i); - if (page == NULL) - break; - - /* the book-keeping above promises that we've tried - * all the indices from start to end, so we don't - * stop if anyone returns an error. This may not be good. */ - if (Page_Uptodate(page)) - goto next_page; - - if ((rc = ll_page_matches(page, flags)) <= 0) { - LL_CDEBUG_PAGE(D_READA | D_PAGE, page, - "lock match failed: rc %d\n", rc); - goto next_page; + list_for_each_entry(scan, &ras->ras_read_beads, lrr_linkage) { + if (scan->lrr_reader == current) + return scan; + } + return NULL; +} + +struct ll_ra_read *ll_ra_read_get(struct file *f) +{ + struct ll_readahead_state *ras; + struct ll_ra_read *bead; + + ras = ll_ras_get(f); + + spin_lock(&ras->ras_lock); + bead = ll_ra_read_get_locked(ras); + spin_unlock(&ras->ras_lock); + return bead; +} + +static int ll_read_ahead_page(struct obd_export *exp, struct obd_io_group *oig, + int index, struct address_space *mapping) +{ + struct ll_async_page *llap; + struct page *page; + unsigned int gfp_mask = 0; + int rc = 0; + + gfp_mask = GFP_HIGHUSER & ~__GFP_WAIT; +#ifdef __GFP_NOWARN + gfp_mask |= __GFP_NOWARN; +#endif + page = grab_cache_page_nowait_gfp(mapping, index, gfp_mask); + if (page == NULL) { + ll_ra_stats_inc(mapping, RA_STAT_FAILED_GRAB_PAGE); + CDEBUG(D_READA, "g_c_p_n failed\n"); + return 0; + } + + /* Check if page was truncated or reclaimed */ + if (page->mapping != mapping) { + ll_ra_stats_inc(mapping, RA_STAT_WRONG_GRAB_PAGE); + CDEBUG(D_READA, "g_c_p_n returned invalid page\n"); + GOTO(unlock_page, rc = 0); + } + + /* we do this first so that we can see the page in the /proc + * accounting */ + llap = llap_from_page(page, LLAP_ORIGIN_READAHEAD); + if (IS_ERR(llap) || llap->llap_defer_uptodate) { + if (PTR_ERR(llap) == -ENOLCK) { + ll_ra_stats_inc(mapping, RA_STAT_FAILED_MATCH); + CDEBUG(D_READA | D_PAGE, + "Adding page to cache failed index " + "%d\n", index); + CDEBUG(D_READA, "nolock page\n"); + GOTO(unlock_page, rc = -ENOLCK); } + CDEBUG(D_READA, "read-ahead page\n"); + GOTO(unlock_page, rc = 0); + } - llap = llap_from_page(page); - if (IS_ERR(llap) || llap->llap_defer_uptodate) - goto next_page; + /* skip completed pages */ + if (Page_Uptodate(page)) + GOTO(unlock_page, rc = 0); - rc = ll_issue_page_read(exp, llap, oig, 1); - if (rc == 0) - LL_CDEBUG_PAGE(D_PAGE, page, "started read-ahead\n"); - if (rc) { - next_page: - LL_CDEBUG_PAGE(D_PAGE, page, "skipping read-ahead\n"); + /* bail out when we hit the end of the lock. */ + rc = ll_issue_page_read(exp, llap, oig, 1); + if (rc == 0) { + LL_CDEBUG_PAGE(D_READA | D_PAGE, page, "started read-ahead\n"); + rc = 1; + } else { +unlock_page: + unlock_page(page); + LL_CDEBUG_PAGE(D_READA | D_PAGE, page, "skipping read-ahead\n"); + } + page_cache_release(page); + return rc; +} - unlock_page(page); +/* ra_io_arg will be filled in the beginning of ll_readahead with + * ras_lock, then the following ll_read_ahead_pages will read RA + * pages according to this arg, all the items in this structure are + * counted by page index. + */ +struct ra_io_arg { + unsigned long ria_start; /* start offset of read-ahead*/ + unsigned long ria_end; /* end offset of read-ahead*/ + /* If stride read pattern is detected, ria_stoff means where + * stride read is started. Note: for normal read-ahead, the + * value here is meaningless, and also it will not be accessed*/ + pgoff_t ria_stoff; + /* ria_length and ria_pages are the length and pages length in the + * stride I/O mode. And they will also be used to check whether + * it is stride I/O read-ahead in the read-ahead pages*/ + unsigned long ria_length; + unsigned long ria_pages; +}; + +#define RIA_DEBUG(ria) \ + CDEBUG(D_READA, "rs %lu re %lu ro %lu rl %lu rp %lu\n", \ + ria->ria_start, ria->ria_end, ria->ria_stoff, ria->ria_length,\ + ria->ria_pages) + +#define RAS_INCREASE_STEP (1024 * 1024 >> CFS_PAGE_SHIFT) + +static inline int stride_io_mode(struct ll_readahead_state *ras) +{ + return ras->ras_consecutive_stride_requests > 1; +} + +/* The function calculates how much pages will be read in + * [off, off + length], which will be read by stride I/O mode, + * stride_offset = st_off, stride_lengh = st_len, + * stride_pages = st_pgs + */ +static unsigned long +stride_pg_count(pgoff_t st_off, unsigned long st_len, unsigned long st_pgs, + unsigned long off, unsigned length) +{ + unsigned long cont_len = st_off > off ? st_off - off : 0; + __u64 stride_len = length + off > st_off ? + length + off + 1 - st_off : 0; + unsigned long left, pg_count; + + if (st_len == 0 || length == 0) + return length; + + left = do_div(stride_len, st_len); + left = min(left, st_pgs); + + pg_count = left + stride_len * st_pgs + cont_len; + + LASSERT(pg_count >= left); + + CDEBUG(D_READA, "st_off %lu, st_len %lu st_pgs %lu off %lu length %u" + "pgcount %lu\n", st_off, st_len, st_pgs, off, length, pg_count); + + return pg_count; +} + +static int ria_page_count(struct ra_io_arg *ria) +{ + __u64 length = ria->ria_end >= ria->ria_start ? + ria->ria_end - ria->ria_start + 1 : 0; + + return stride_pg_count(ria->ria_stoff, ria->ria_length, + ria->ria_pages, ria->ria_start, + length); +} + +/*Check whether the index is in the defined ra-window */ +static int ras_inside_ra_window(unsigned long idx, struct ra_io_arg *ria) +{ + /* If ria_length == ria_pages, it means non-stride I/O mode, + * idx should always inside read-ahead window in this case + * For stride I/O mode, just check whether the idx is inside + * the ria_pages. */ + return ria->ria_length == 0 || ria->ria_length == ria->ria_pages || + (idx - ria->ria_stoff) % ria->ria_length < ria->ria_pages; +} + +static int ll_read_ahead_pages(struct obd_export *exp, + struct obd_io_group *oig, + struct ra_io_arg *ria, + unsigned long *reserved_pages, + struct address_space *mapping, + unsigned long *ra_end) +{ + int rc, count = 0, stride_ria; + unsigned long page_idx; + + LASSERT(ria != NULL); + RIA_DEBUG(ria); + + stride_ria = ria->ria_length > ria->ria_pages && ria->ria_pages > 0; + for (page_idx = ria->ria_start; page_idx <= ria->ria_end && + *reserved_pages > 0; page_idx++) { + if (ras_inside_ra_window(page_idx, ria)) { + /* If the page is inside the read-ahead window*/ + rc = ll_read_ahead_page(exp, oig, page_idx, mapping); + if (rc == 1) { + (*reserved_pages)--; + count ++; + } else if (rc == -ENOLCK) + break; + } else if (stride_ria) { + /* If it is not in the read-ahead window, and it is + * read-ahead mode, then check whether it should skip + * the stride gap */ + pgoff_t offset; + /* FIXME: This assertion only is valid when it is for + * forward read-ahead, it will be fixed when backward + * read-ahead is implemented */ + LASSERTF(page_idx > ria->ria_stoff, "since %lu in the" + " gap of ra window,it should bigger than stride" + " offset %lu \n", page_idx, ria->ria_stoff); + + offset = page_idx - ria->ria_stoff; + offset = offset % (ria->ria_length); + if (offset > ria->ria_pages) { + page_idx += ria->ria_length - offset; + CDEBUG(D_READA, "i %lu skip %lu \n", page_idx, + ria->ria_length - offset); + continue; + } } - page_cache_release(page); } + *ra_end = page_idx; + return count; +} + +static int ll_readahead(struct ll_readahead_state *ras, + struct obd_export *exp, struct address_space *mapping, + struct obd_io_group *oig, int flags) +{ + unsigned long start = 0, end = 0, reserved; + unsigned long ra_end, len; + struct inode *inode; + struct lov_stripe_md *lsm; + struct ll_ra_read *bead; + struct ost_lvb lvb; + struct ra_io_arg ria = { 0 }; + int ret = 0; + __u64 kms; + ENTRY; + + inode = mapping->host; + lsm = ll_i2info(inode)->lli_smd; + + lov_stripe_lock(lsm); + inode_init_lvb(inode, &lvb); + obd_merge_lvb(ll_i2dtexp(inode), lsm, &lvb, 1); + kms = lvb.lvb_size; + lov_stripe_unlock(lsm); + if (kms == 0) { + ll_ra_stats_inc(mapping, RA_STAT_ZERO_LEN); + RETURN(0); + } + + spin_lock(&ras->ras_lock); + bead = ll_ra_read_get_locked(ras); + /* Enlarge the RA window to encompass the full read */ + if (bead != NULL && ras->ras_window_start + ras->ras_window_len < + bead->lrr_start + bead->lrr_count) { + ras->ras_window_len = bead->lrr_start + bead->lrr_count - + ras->ras_window_start; + } + /* Reserve a part of the read-ahead window that we'll be issuing */ + if (ras->ras_window_len) { + start = ras->ras_next_readahead; + end = ras->ras_window_start + ras->ras_window_len - 1; + } + if (end != 0) { + /* Truncate RA window to end of file */ + end = min(end, (unsigned long)((kms - 1) >> CFS_PAGE_SHIFT)); + ras->ras_next_readahead = max(end, end + 1); + RAS_CDEBUG(ras); + } + ria.ria_start = start; + ria.ria_end = end; + /* If stride I/O mode is detected, get stride window*/ + if (stride_io_mode(ras)) { + ria.ria_stoff = ras->ras_stride_offset; + ria.ria_length = ras->ras_stride_length; + ria.ria_pages = ras->ras_stride_pages; + } + spin_unlock(&ras->ras_lock); + + if (end == 0) { + ll_ra_stats_inc(mapping, RA_STAT_ZERO_WINDOW); + RETURN(0); + } + len = ria_page_count(&ria); + if (len == 0) + RETURN(0); + + reserved = ll_ra_count_get(ll_i2sbi(inode), len); + + if (reserved < len) + ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT); + + CDEBUG(D_READA, "reserved page %lu \n", reserved); + + ret = ll_read_ahead_pages(exp, oig, &ria, &reserved, mapping, &ra_end); + + LASSERTF(reserved >= 0, "reserved %lu\n", reserved); + if (reserved != 0) + ll_ra_count_put(ll_i2sbi(inode), reserved); + + if (ra_end == end + 1 && ra_end == (kms >> CFS_PAGE_SHIFT)) + ll_ra_stats_inc(mapping, RA_STAT_EOF); + + /* if we didn't get to the end of the region we reserved from + * the ras we need to go back and update the ras so that the + * next read-ahead tries from where we left off. we only do so + * if the region we failed to issue read-ahead on is still ahead + * of the app and behind the next index to start read-ahead from */ + CDEBUG(D_READA, "ra_end %lu end %lu stride end %lu \n", + ra_end, end, ria.ria_end); + + if (ra_end != (end + 1)) { + spin_lock(&ras->ras_lock); + if (ra_end < ras->ras_next_readahead && + index_in_window(ra_end, ras->ras_window_start, 0, + ras->ras_window_len)) { + ras->ras_next_readahead = ra_end; + RAS_CDEBUG(ras); + } + spin_unlock(&ras->ras_lock); + } + + RETURN(ret); +} + +static void ras_set_start(struct ll_readahead_state *ras, unsigned long index) +{ + ras->ras_window_start = index & (~(RAS_INCREASE_STEP - 1)); +} + +/* called with the ras_lock held or from places where it doesn't matter */ +static void ras_reset(struct ll_readahead_state *ras, unsigned long index) +{ + ras->ras_last_readpage = index; + ras->ras_consecutive_requests = 0; + ras->ras_consecutive_pages = 0; + ras->ras_window_len = 0; + ras_set_start(ras, index); + ras->ras_next_readahead = max(ras->ras_window_start, index); + + RAS_CDEBUG(ras); } /* called with the ras_lock held or from places where it doesn't matter */ -static void ll_readahead_set(struct inode *inode, - struct ll_readahead_state *ras, - unsigned long index) -{ - ras->ras_next_index = index; - if (ras->ras_next_index != ~0UL) - ras->ras_next_index++; - ras->ras_window = LL_RA_MIN(inode); - ras->ras_last = ras->ras_next_index + ras->ras_window; - if (ras->ras_last < ras->ras_next_index) - ras->ras_last = ~0UL; - CDEBUG(D_READA, "ni %lu last %lu win %lu: set %lu\n", - ras->ras_next_index, ras->ras_last, ras->ras_window, - index); +static void ras_stride_reset(struct ll_readahead_state *ras) +{ + ras->ras_consecutive_stride_requests = 0; + RAS_CDEBUG(ras); } void ll_readahead_init(struct inode *inode, struct ll_readahead_state *ras) { spin_lock_init(&ras->ras_lock); - ll_readahead_set(inode, ras, 0); + ras_reset(ras, 0); + ras->ras_requests = 0; + INIT_LIST_HEAD(&ras->ras_read_beads); +} + +/* Check whether the read request is in the stride window. + * If it is in the stride window, return 1, otherwise return 0. + * and also update stride_gap and stride_pages. + */ +static int index_in_stride_window(unsigned long index, + struct ll_readahead_state *ras, + struct inode *inode) +{ + int stride_gap = index - ras->ras_last_readpage - 1; + + LASSERT(stride_gap != 0); + + if (ras->ras_consecutive_pages == 0) + return 0; + + /*Otherwise check the stride by itself */ + if ((ras->ras_stride_length - ras->ras_stride_pages) == stride_gap && + ras->ras_consecutive_pages == ras->ras_stride_pages) + return 1; + + if (stride_gap >= 0) { + /* + * only set stride_pages, stride_length if + * it is forward reading ( stride_gap > 0) + */ + ras->ras_stride_pages = ras->ras_consecutive_pages; + ras->ras_stride_length = stride_gap + ras->ras_consecutive_pages; + } else { + /* + * If stride_gap < 0,(back_forward reading), + * reset the stride_pages/length. + * FIXME:back_ward stride I/O read. + * + */ + ras->ras_stride_pages = 0; + ras->ras_stride_length = 0; + } + RAS_CDEBUG(ras); + + return 0; +} + +static unsigned long +stride_page_count(struct ll_readahead_state *ras, unsigned long len) +{ + return stride_pg_count(ras->ras_stride_offset, ras->ras_stride_length, + ras->ras_stride_pages, ras->ras_stride_offset, + len); +} + +/* Stride Read-ahead window will be increased inc_len according to + * stride I/O pattern */ +static void ras_stride_increase_window(struct ll_readahead_state *ras, + struct ll_ra_info *ra, + unsigned long inc_len) +{ + unsigned long left, step, window_len; + unsigned long stride_len; + + LASSERT(ras->ras_stride_length > 0); + + stride_len = ras->ras_window_start + ras->ras_window_len - + ras->ras_stride_offset; + + LASSERTF(stride_len >= 0, "window_start %lu, window_len %lu" + " stride_offset %lu\n", ras->ras_window_start, + ras->ras_window_len, ras->ras_stride_offset); + + left = stride_len % ras->ras_stride_length; + + window_len = ras->ras_window_len - left; + + if (left < ras->ras_stride_pages) + left += inc_len; + else + left = ras->ras_stride_pages + inc_len; + + LASSERT(ras->ras_stride_pages != 0); + + step = left / ras->ras_stride_pages; + left %= ras->ras_stride_pages; + + window_len += step * ras->ras_stride_length + left; + + if (stride_page_count(ras, window_len) <= ra->ra_max_pages) + ras->ras_window_len = window_len; + + RAS_CDEBUG(ras); } -static void ll_readahead_update(struct inode *inode, - struct ll_readahead_state *ras, - unsigned long index, int hit) +/* Set stride I/O read-ahead window start offset */ +static void ras_set_stride_offset(struct ll_readahead_state *ras) { - unsigned long issued_start, new_last; + unsigned long window_len = ras->ras_next_readahead - + ras->ras_window_start; + unsigned long left; + + LASSERT(ras->ras_stride_length != 0); + + left = window_len % ras->ras_stride_length; + + ras->ras_stride_offset = ras->ras_next_readahead - left; + + RAS_CDEBUG(ras); +} + +static void ras_update(struct ll_sb_info *sbi, struct inode *inode, + struct ll_readahead_state *ras, unsigned long index, + unsigned hit) +{ + struct ll_ra_info *ra = &sbi->ll_ra_info; + int zero = 0, stride_zero = 0, stride_detect = 0, ra_miss = 0; + ENTRY; spin_lock(&ras->ras_lock); - /* we're interested in noticing the index's relation to the - * previously issued read-ahead pages */ - issued_start = ras->ras_next_index - ras->ras_window - 1; - if (issued_start > ras->ras_next_index) - issued_start = 0; - - CDEBUG(D_READA, "ni %lu last %lu win %lu: %s ind %lu start %lu\n", - ras->ras_next_index, ras->ras_last, ras->ras_window, - hit ? "hit" : "miss", index, issued_start); - if (!hit && - index == ras->ras_next_index && index == ras->ras_last + 1) { - /* special case the kernel's read-ahead running into the - * page just beyond our read-ahead window as an extension - * of our read-ahead. sigh. wishing it was easier to - * turn off 2.4's read-ahead. */ - ras->ras_window = min(LL_RA_MAX(inode), ras->ras_window + 1); - if (index != ~0UL) - ras->ras_next_index = index + 1; - ras->ras_last = index; - } else if (!hit && - (index > issued_start || ras->ras_next_index >= index)) { - /* deal with a miss way out of the window. we interpret - * this as a seek and restart the window */ - ll_readahead_set(inode, ras, index); - - } else if (!hit && - issued_start <= index && index < ras->ras_next_index) { - /* a miss inside the window? surely its memory pressure - * evicting our read pages before the app can see them. - * we shrink the window aggressively */ - unsigned long old_window = ras->ras_window; - - ras->ras_window = max(ras->ras_window / 2, LL_RA_MIN(inode)); - ras->ras_last -= old_window - ras->ras_window; - if (ras->ras_next_index > ras->ras_last) - ras->ras_next_index = ras->ras_last + 1; - CDEBUG(D_READA, "ni %lu last %lu win %lu: miss inside\n", - ras->ras_next_index, ras->ras_last, ras->ras_window); - - } else if (hit && - issued_start <= index && index < ras->ras_next_index) { - /* a hit inside the window. grow the window by twice the - * number of pages that are satisified within the window. */ - ras->ras_window = min(LL_RA_MAX(inode), ras->ras_window + 2); - - /* we want the next readahead pass to issue a windows worth - * beyond where the app currently is */ - new_last = index + ras->ras_window; - if (new_last > ras->ras_last) - ras->ras_last = new_last; - - CDEBUG(D_READA, "ni %lu last %lu win %lu: extended window/last\n", - ras->ras_next_index, ras->ras_last, ras->ras_window); + ll_ra_stats_inc_sbi(sbi, hit ? RA_STAT_HIT : RA_STAT_MISS); + + /* reset the read-ahead window in two cases. First when the app seeks + * or reads to some other part of the file. Secondly if we get a + * read-ahead miss that we think we've previously issued. This can + * be a symptom of there being so many read-ahead pages that the VM is + * reclaiming it before we get to it. */ + if (!index_in_window(index, ras->ras_last_readpage, 8, 8)) { + zero = 1; + ll_ra_stats_inc_sbi(sbi, RA_STAT_DISTANT_READPAGE); + /* check whether it is in stride I/O mode*/ + if (!index_in_stride_window(index, ras, inode)) + stride_zero = 1; + } else if (!hit && ras->ras_window_len && + index < ras->ras_next_readahead && + index_in_window(index, ras->ras_window_start, 0, + ras->ras_window_len)) { + zero = 1; + ra_miss = 1; + /* If it hits read-ahead miss and the stride I/O is still + * not detected, reset stride stuff to re-detect the whole + * stride I/O mode to avoid complication */ + if (!stride_io_mode(ras)) + stride_zero = 1; + ll_ra_stats_inc_sbi(sbi, RA_STAT_MISS_IN_WINDOW); + } + + /* On the second access to a file smaller than the tunable + * ra_max_read_ahead_whole_pages trigger RA on all pages in the + * file up to ra_max_pages. This is simply a best effort and + * only occurs once per open file. Normal RA behavior is reverted + * to for subsequent IO. The mmap case does not increment + * ras_requests and thus can never trigger this behavior. */ + if (ras->ras_requests == 2 && !ras->ras_request_index) { + __u64 kms_pages; + + kms_pages = (i_size_read(inode) + CFS_PAGE_SIZE - 1) >> + CFS_PAGE_SHIFT; + + CDEBUG(D_READA, "kmsp "LPU64" mwp %lu mp %lu\n", kms_pages, + ra->ra_max_read_ahead_whole_pages, ra->ra_max_pages); + + if (kms_pages && + kms_pages <= ra->ra_max_read_ahead_whole_pages) { + ras->ras_window_start = 0; + ras->ras_last_readpage = 0; + ras->ras_next_readahead = 0; + ras->ras_window_len = min(ra->ra_max_pages, + ra->ra_max_read_ahead_whole_pages); + GOTO(out_unlock, 0); + } + } + + if (zero) { + /* If it is discontinuous read, check + * whether it is stride I/O mode*/ + if (stride_zero) { + ras_reset(ras, index); + ras->ras_consecutive_pages++; + ras_stride_reset(ras); + RAS_CDEBUG(ras); + GOTO(out_unlock, 0); + } else { + /* The read is still in stride window or + * it hits read-ahead miss */ + + /* If ra-window miss is hitted, which probably means VM + * pressure, and some read-ahead pages were reclaimed.So + * the length of ra-window will not increased, but also + * not reset to avoid redetecting the stride I/O mode.*/ + ras->ras_consecutive_requests = 0; + if (!ra_miss) { + ras->ras_consecutive_pages = 0; + if (++ras->ras_consecutive_stride_requests > 1) + stride_detect = 1; + } + RAS_CDEBUG(ras); + } + } else if (ras->ras_consecutive_stride_requests > 1) { + /* If this is contiguous read but in stride I/O mode + * currently, check whether stride step still is valid, + * if invalid, it will reset the stride ra window*/ + if (ras->ras_consecutive_pages + 1 > ras->ras_stride_pages) + ras_stride_reset(ras); } + ras->ras_last_readpage = index; + ras->ras_consecutive_pages++; + ras_set_start(ras, index); + ras->ras_next_readahead = max(ras->ras_window_start, + ras->ras_next_readahead); + RAS_CDEBUG(ras); + + /* Trigger RA in the mmap case where ras_consecutive_requests + * is not incremented and thus can't be used to trigger RA */ + if (!ras->ras_window_len && ras->ras_consecutive_pages == 4) { + ras->ras_window_len = RAS_INCREASE_STEP; + GOTO(out_unlock, 0); + } + + /* Initially reset the stride window offset to next_readahead*/ + if (ras->ras_consecutive_stride_requests == 2 && stride_detect) + ras_set_stride_offset(ras); + + /* The initial ras_window_len is set to the request size. To avoid + * uselessly reading and discarding pages for random IO the window is + * only increased once per consecutive request received. */ + if ((ras->ras_consecutive_requests > 1 && + !ras->ras_request_index) || stride_detect) { + if (stride_io_mode(ras)) + ras_stride_increase_window(ras, ra, RAS_INCREASE_STEP); + else + ras->ras_window_len = min(ras->ras_window_len + + RAS_INCREASE_STEP, + ra->ra_max_pages); + } + EXIT; +out_unlock: + RAS_CDEBUG(ras); + ras->ras_request_index++; spin_unlock(&ras->ras_lock); + return; +} + +int ll_writepage(struct page *page) +{ + struct inode *inode = page->mapping->host; + struct ll_inode_info *lli = ll_i2info(inode); + struct obd_export *exp; + struct ll_async_page *llap; + int rc = 0; + ENTRY; + + LASSERT(PageLocked(page)); + + exp = ll_i2dtexp(inode); + if (exp == NULL) + GOTO(out, rc = -EINVAL); + + llap = llap_from_page(page, LLAP_ORIGIN_WRITEPAGE); + if (IS_ERR(llap)) + GOTO(out, rc = PTR_ERR(llap)); + + LASSERT(!llap->llap_nocache); + LASSERT(!PageWriteback(page)); + set_page_writeback(page); + + page_cache_get(page); + if (llap->llap_write_queued) { + LL_CDEBUG_PAGE(D_PAGE, page, "marking urgent\n"); + rc = obd_set_async_flags(exp, lli->lli_smd, NULL, + llap->llap_cookie, + ASYNC_READY | ASYNC_URGENT); + } else { + rc = queue_or_sync_write(exp, inode, llap, CFS_PAGE_SIZE, + ASYNC_READY | ASYNC_URGENT); + } + if (rc) { + /* re-dirty page on error so it retries write */ + if (PageWriteback(page)) + end_page_writeback(page); + + /* resend page only for not started IO*/ + if (!PageError(page)) + ll_redirty_page(page); + + page_cache_release(page); + } +out: + if (rc) { + if (!lli->lli_async_rc) + lli->lli_async_rc = rc; + /* resend page only for not started IO*/ + unlock_page(page); + } + RETURN(rc); } /* @@ -743,78 +2014,86 @@ static void ll_readahead_update(struct inode *inode, */ int ll_readpage(struct file *filp, struct page *page) { - struct ll_file_data *fd = filp->private_data; + struct ll_file_data *fd = LUSTRE_FPRIVATE(filp); struct inode *inode = page->mapping->host; struct obd_export *exp; struct ll_async_page *llap; struct obd_io_group *oig = NULL; + struct lustre_handle *lockh = NULL; int rc; ENTRY; LASSERT(PageLocked(page)); LASSERT(!PageUptodate(page)); - CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p),offset="LPX64"\n", + CDEBUG(D_VFSTRACE, "VFS Op:inode=%lu/%u(%p),offset=%Lu=%#Lx\n", inode->i_ino, inode->i_generation, inode, - (((obd_off)page->index) << PAGE_SHIFT)); + (((loff_t)page->index) << CFS_PAGE_SHIFT), + (((loff_t)page->index) << CFS_PAGE_SHIFT)); LASSERT(atomic_read(&filp->f_dentry->d_inode->i_count) > 0); + if (!ll_i2info(inode)->lli_smd) { + /* File with no objects - one big hole */ + /* We use this just for remove_from_page_cache that is not + * exported, we'd make page back up to date. */ + ll_truncate_complete_page(page); + clear_page(kmap(page)); + kunmap(page); + SetPageUptodate(page); + unlock_page(page); + RETURN(0); + } + rc = oig_init(&oig); if (rc < 0) GOTO(out, rc); - exp = ll_i2obdexp(inode); + exp = ll_i2dtexp(inode); if (exp == NULL) GOTO(out, rc = -EINVAL); - llap = llap_from_page(page); - if (IS_ERR(llap)) + if (fd->fd_flags & LL_FILE_GROUP_LOCKED) + lockh = &fd->fd_cwlockh; + + llap = llap_from_page_with_lockh(page, LLAP_ORIGIN_READPAGE, lockh); + if (IS_ERR(llap)) { + if (PTR_ERR(llap) == -ENOLCK) { + CWARN("ino %lu page %lu (%llu) not covered by " + "a lock (mmap?). check debug logs.\n", + inode->i_ino, page->index, + (long long)page->index << PAGE_CACHE_SHIFT); + } GOTO(out, rc = PTR_ERR(llap)); + } + + if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages) + ras_update(ll_i2sbi(inode), inode, &fd->fd_ras, page->index, + llap->llap_defer_uptodate); + if (llap->llap_defer_uptodate) { - ll_readahead_update(inode, &fd->fd_ras, page->index, 1); - ll_readahead(&fd->fd_ras, exp, page->mapping, oig,fd->fd_flags); - obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, - oig); + /* This is the callpath if we got the page from a readahead */ + llap->llap_ra_used = 1; + rc = ll_readahead(&fd->fd_ras, exp, page->mapping, oig, + fd->fd_flags); + if (rc > 0) + obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, + NULL, oig); LL_CDEBUG_PAGE(D_PAGE, page, "marking uptodate from defer\n"); SetPageUptodate(page); unlock_page(page); GOTO(out_oig, rc = 0); } - ll_readahead_update(inode, &fd->fd_ras, page->index, 0); - - rc = ll_page_matches(page, fd->fd_flags); - if (rc < 0) { - LL_CDEBUG_PAGE(D_ERROR, page, "lock match failed: rc %d\n", rc); - GOTO(out, rc); - } - - if (rc == 0) { - static unsigned long next_print; - CDEBUG(D_INODE, "ino %lu page %lu (%llu) didn't match a lock\n", - inode->i_ino, page->index, - (long long)page->index << PAGE_CACHE_SHIFT); - if (time_after(jiffies, next_print)) { - CERROR("ino %lu page %lu (%llu) not covered by " - "a lock (mmap?). check debug logs.\n", - inode->i_ino, page->index, - (long long)page->index << PAGE_CACHE_SHIFT); - ldlm_dump_all_namespaces(); - if (next_print == 0) { - CERROR("%s\n", portals_debug_dumpstack()); - portals_debug_dumplog(); - } - next_print = jiffies + 30 * HZ; - } - } - rc = ll_issue_page_read(exp, llap, oig, 0); if (rc) GOTO(out, rc); LL_CDEBUG_PAGE(D_PAGE, page, "queued readpage\n"); - if ((ll_i2sbi(inode)->ll_flags & LL_SBI_READAHEAD)) - ll_readahead(&fd->fd_ras, exp, page->mapping, oig,fd->fd_flags); + /* We have just requested the actual page we want, see if we can tack + * on some readahead to that page's RPC before it is sent. */ + if (ll_i2sbi(inode)->ll_ra_info.ra_max_pages) + ll_readahead(&fd->fd_ras, exp, page->mapping, oig, + fd->fd_flags); rc = obd_trigger_group_io(exp, ll_i2info(inode)->lli_smd, NULL, oig); @@ -827,37 +2106,273 @@ out_oig: RETURN(rc); } -#if 0 -/* this is for read pages. we issue them as ready but not urgent. when - * someone waits on them we fire them off, hopefully merged with adjacent - * reads that were queued by read-ahead. */ -int ll_sync_page(struct page *page) +static void ll_file_put_pages(struct page **pages, int numpages) +{ + int i; + struct page **pp; + ENTRY; + + for (i = 0, pp = pages; i < numpages; i++, pp++) { + if (*pp) { + LL_CDEBUG_PAGE(D_PAGE, (*pp), "free\n"); + __ll_put_llap(*pp); + if (page_private(*pp)) + CERROR("the llap wasn't freed\n"); + (*pp)->mapping = NULL; + if (page_count(*pp) != 1) + CERROR("page %p, flags %#lx, count %i, private %p\n", + (*pp), (unsigned long)(*pp)->flags, page_count(*pp), + (void*)page_private(*pp)); + __free_pages(*pp, 0); + } + } + OBD_FREE(pages, numpages * sizeof(struct page*)); + EXIT; +} + +static struct page **ll_file_prepare_pages(int numpages, struct inode *inode, + unsigned long first) +{ + struct page **pages; + int i; + int rc = 0; + ENTRY; + + OBD_ALLOC(pages, sizeof(struct page *) * numpages); + if (pages == NULL) + RETURN(ERR_PTR(-ENOMEM)); + for (i = 0; i < numpages; i++) { + struct page *page; + struct ll_async_page *llap; + + page = alloc_pages(GFP_HIGHUSER, 0); + if (page == NULL) + GOTO(err, rc = -ENOMEM); + pages[i] = page; + /* llap_from_page needs page index and mapping to be set */ + page->index = first++; + page->mapping = inode->i_mapping; + llap = llap_from_page(page, LLAP_ORIGIN_LOCKLESS_IO); + if (IS_ERR(llap)) + GOTO(err, rc = PTR_ERR(llap)); + llap->llap_lockless_io_page = 1; + } + RETURN(pages); +err: + ll_file_put_pages(pages, numpages); + RETURN(ERR_PTR(rc)); + } + +static ssize_t ll_file_copy_pages(struct page **pages, int numpages, + char *buf, loff_t pos, size_t count, int rw) +{ + ssize_t amount = 0; + int i; + int updatechecksum = ll_i2sbi(pages[0]->mapping->host)->ll_flags & + LL_SBI_CHECKSUM; + ENTRY; + + for (i = 0; i < numpages; i++) { + unsigned offset, bytes, left; + char *vaddr; + + vaddr = kmap(pages[i]); + offset = pos & (CFS_PAGE_SIZE - 1); + bytes = min_t(unsigned, CFS_PAGE_SIZE - offset, count); + LL_CDEBUG_PAGE(D_PAGE, pages[i], "op = %s, addr = %p, " + "buf = %p, bytes = %u\n", + (rw == WRITE) ? "CFU" : "CTU", + vaddr + offset, buf, bytes); + if (rw == WRITE) { + left = copy_from_user(vaddr + offset, buf, bytes); + if (updatechecksum) { + struct ll_async_page *llap; + + llap = llap_cast_private(pages[i]); + llap->llap_checksum = crc32_le(0, vaddr, + CFS_PAGE_SIZE); + } + } else { + left = copy_to_user(buf, vaddr + offset, bytes); + } + kunmap(pages[i]); + amount += bytes; + if (left) { + amount -= left; + break; + } + buf += bytes; + count -= bytes; + pos += bytes; + } + if (amount == 0) + RETURN(-EFAULT); + RETURN(amount); +} + +static int ll_file_oig_pages(struct inode * inode, struct page **pages, + int numpages, loff_t pos, size_t count, int rw) { + struct obd_io_group *oig; + struct ll_inode_info *lli = ll_i2info(inode); struct obd_export *exp; - struct ll_async_page *llap; + loff_t org_pos = pos; + obd_flag brw_flags; int rc; + int i; ENTRY; - /* we're using a low bit flag to signify that a queued read should - * be issued once someone goes to lock it. it is also cleared - * as the page is built into an RPC */ - if (!test_and_clear_bit(LL_PRIVBITS_READ, &page->private)) - RETURN(0); - - /* careful to only deref page->mapping after checking the bit */ - exp = ll_i2obdexp(page->mapping->host); + exp = ll_i2dtexp(inode); if (exp == NULL) RETURN(-EINVAL); + rc = oig_init(&oig); + if (rc) + RETURN(rc); + brw_flags = OBD_BRW_SRVLOCK; + if (capable(CAP_SYS_RESOURCE)) + brw_flags |= OBD_BRW_NOQUOTA; + + for (i = 0; i < numpages; i++) { + struct ll_async_page *llap; + unsigned from, bytes; + + from = pos & (CFS_PAGE_SIZE - 1); + bytes = min_t(unsigned, CFS_PAGE_SIZE - from, + count - pos + org_pos); + llap = llap_cast_private(pages[i]); + LASSERT(llap); + + lock_page(pages[i]); + + LL_CDEBUG_PAGE(D_PAGE, pages[i], "offset "LPU64"," + " from %u, bytes = %u\n", + (__u64)pos, from, bytes); + LASSERTF(pos >> CFS_PAGE_SHIFT == pages[i]->index, + "wrong page index %lu (%lu)\n", + pages[i]->index, + (unsigned long)(pos >> CFS_PAGE_SHIFT)); + rc = obd_queue_group_io(exp, lli->lli_smd, NULL, oig, + llap->llap_cookie, + (rw == WRITE) ? + OBD_BRW_WRITE:OBD_BRW_READ, + from, bytes, brw_flags, + ASYNC_READY | ASYNC_URGENT | + ASYNC_COUNT_STABLE | ASYNC_GROUP_SYNC); + if (rc) { + i++; + GOTO(out, rc); + } + pos += bytes; + } + rc = obd_trigger_group_io(exp, lli->lli_smd, NULL, oig); + if (rc) + GOTO(out, rc); + rc = oig_wait(oig); +out: + while(--i >= 0) + unlock_page(pages[i]); + oig_release(oig); + RETURN(rc); +} - llap = llap_from_page(page); - if (IS_ERR(llap)) - RETURN(PTR_ERR(llap)); - - LL_CDEBUG_PAGE(D_PAGE, page, "setting ready|urgent\n"); +ssize_t ll_file_lockless_io(struct file *file, char *buf, size_t count, + loff_t *ppos, int rw) +{ + loff_t pos; + struct inode *inode = file->f_dentry->d_inode; + ssize_t rc = 0; + int max_pages; + size_t amount = 0; + unsigned long first, last; + ENTRY; - rc = obd_set_async_flags(exp, ll_i2info(page->mapping->host)->lli_smd, - NULL, llap->llap_cookie, - ASYNC_READY|ASYNC_URGENT); - return rc; + if (rw == READ) { + loff_t isize; + + ll_inode_size_lock(inode, 0); + isize = i_size_read(inode); + ll_inode_size_unlock(inode, 0); + if (*ppos >= isize) + GOTO(out, rc = 0); + if (*ppos + count >= isize) + count -= *ppos + count - isize; + if (count == 0) + GOTO(out, rc); + } else { + rc = generic_write_checks(file, ppos, &count, 0); + if (rc) + GOTO(out, rc); + rc = ll_remove_suid(file->f_dentry, file->f_vfsmnt); + if (rc) + GOTO(out, rc); + } + pos = *ppos; + first = pos >> CFS_PAGE_SHIFT; + last = (pos + count - 1) >> CFS_PAGE_SHIFT; + max_pages = PTLRPC_MAX_BRW_PAGES * + ll_i2info(inode)->lli_smd->lsm_stripe_count; + CDEBUG(D_INFO, "%u, stripe_count = %u\n", + PTLRPC_MAX_BRW_PAGES /* max_pages_per_rpc */, + ll_i2info(inode)->lli_smd->lsm_stripe_count); + + while (first <= last && rc >= 0) { + int pages_for_io; + struct page **pages; + size_t bytes = count - amount; + + pages_for_io = min_t(int, last - first + 1, max_pages); + pages = ll_file_prepare_pages(pages_for_io, inode, first); + if (IS_ERR(pages)) { + rc = PTR_ERR(pages); + break; + } + if (rw == WRITE) { + rc = ll_file_copy_pages(pages, pages_for_io, buf, + pos + amount, bytes, rw); + if (rc < 0) + GOTO(put_pages, rc); + bytes = rc; + } + rc = ll_file_oig_pages(inode, pages, pages_for_io, + pos + amount, bytes, rw); + if (rc) + GOTO(put_pages, rc); + if (rw == READ) { + rc = ll_file_copy_pages(pages, pages_for_io, buf, + pos + amount, bytes, rw); + if (rc < 0) + GOTO(put_pages, rc); + bytes = rc; + } + amount += bytes; + buf += bytes; +put_pages: + ll_file_put_pages(pages, pages_for_io); + first += pages_for_io; + /* a short read/write check */ + if (pos + amount < ((loff_t)first << CFS_PAGE_SHIFT)) + break; + } + /* NOTE: don't update i_size and KMS in absence of LDLM locks even + * write makes the file large */ + file_accessed(file); + if (rw == READ && amount < count && rc == 0) { + unsigned long not_cleared; + + not_cleared = clear_user(buf, count - amount); + amount = count - not_cleared; + if (not_cleared) + rc = -EFAULT; + } + if (amount > 0) { + lprocfs_counter_add(ll_i2sbi(inode)->ll_stats, + (rw == WRITE) ? + LPROC_LL_LOCKLESS_WRITE : + LPROC_LL_LOCKLESS_READ, + (long)amount); + *ppos += amount; + RETURN(amount); + } +out: + RETURN(rc); } -#endif