/* -*- 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 <linux/config.h>
+#include <linux/autoconf.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <asm/uaccess.h>
-#include <asm/segment.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <linux/smp_lock.h>
#define DEBUG_SUBSYSTEM S_LLITE
-#include <linux/lustre_mds.h>
-#include <linux/lustre_lite.h>
+//#include <lustre_mdc.h>
+#include <lustre_lite.h>
+#include <obd_cksum.h>
#include "llite_internal.h"
#include <linux/lustre_compat25.h>
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)
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_valid = OBD_MD_FLID;
- 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);
+ }
+
+ 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);
+ }
- CDEBUG(D_INFO, "calling punch for "LPX64" (all bytes after %Lu)\n",
- oa.o_id, inode->i_size);
+ 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);
+ }
+ }
- /* 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);
+ 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_id = lsm->lsm_object_id;
oa.o_mode = inode->i_mode;
- oa.o_valid = OBD_MD_FLID | OBD_MD_FLMODE | OBD_MD_FLTYPE;
-
- rc = obd_brw(OBD_BRW_CHECK, ll_i2obdexp(inode), &oa, lsm, 1, &pga,
- NULL);
+ oa.o_id = lsm->lsm_object_id;
+ oa.o_gr = lsm->lsm_object_gr;
+ 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);
+
+ 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);
}
/* 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);
}
return rc;
}
-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;
- LASSERT(cmd != OBD_BRW_READ);
-
/* 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
* 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
+/* 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:
+ * 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.
+ * 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
+ * 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
*/
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;
- lsm = ll_i2info(page->mapping->host)->lli_smd;
- kms = lov_merge_size(lsm, 1);
+ 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 << PAGE_SHIFT) >= kms)
+ if (((__u64)page->index << CFS_PAGE_SHIFT) >= kms)
return 0;
/* catch sub-page write at end of file */
- if (((__u64)page->index << PAGE_SHIFT) + PAGE_SIZE > kms)
- return kms % PAGE_SIZE;
+ if (((__u64)page->index << CFS_PAGE_SHIFT) + CFS_PAGE_SIZE > kms)
+ return kms % CFS_PAGE_SIZE;
- return PAGE_SIZE;
+ return CFS_PAGE_SIZE;
}
void ll_inode_fill_obdo(struct inode *inode, int cmd, struct obdo *oa)
lsm = ll_i2info(inode)->lli_smd;
oa->o_id = lsm->lsm_object_id;
- oa->o_valid = OBD_MD_FLID;
+ 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);
- 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);
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_lock);
- sbi->ll_pglist_gen++;
- list_add_tail(&llap->llap_proc_item, &sbi->ll_pglist);
- spin_unlock(&sbi->ll_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. */
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;
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);
}
+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 ll_ra_info *ra = &sbi->ll_ra_info;
unsigned long ret;
ENTRY;
- spin_lock(&sbi->ll_lock);
- ret = min(sbi->ll_max_read_ahead_pages - sbi->ll_read_ahead_pages,
- len);
- sbi->ll_read_ahead_pages += ret;
- spin_unlock(&sbi->ll_lock);
+ ret = min(ra->ra_max_pages - atomic_read(&ra->ra_cur_pages), len);
+ if ((int)ret < 0)
+ GOTO(out, ret = 0);
+ 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);
}
static void ll_ra_count_put(struct ll_sb_info *sbi, unsigned long len)
{
- spin_lock(&sbi->ll_lock);
- LASSERTF(sbi->ll_read_ahead_pages >= len, "r_a_p %lu len %lu\n",
- sbi->ll_read_ahead_pages, len);
- sbi->ll_read_ahead_pages -= len;
- spin_unlock(&sbi->ll_lock);
+ struct ll_ra_info *ra = &sbi->ll_ra_info;
+ atomic_sub(len, &ra->ra_cur_pages);
}
/* called for each page in a completed rpc.*/
-void ll_ap_completion(void *data, int cmd, struct obdo *oa, int rc)
+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);
- if (IS_ERR(llap)) {
- EXIT;
- return;
- }
-
+ 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)
+ 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 (cmd & OBD_BRW_READ) {
if (!llap->llap_defer_uptodate)
SetPageUptodate(page);
} else {
}
ClearPageError(page);
} else {
- if (cmd == OBD_BRW_READ)
+ 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 (0 && cmd == OBD_BRW_WRITE) {
- llap_write_complete(page->mapping->host, llap);
- ll_try_done_writing(page->mapping->host);
+ 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);
- EXIT;
+
+ RETURN(ret);
}
-/* 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_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);
- int rc;
+ struct ll_pglist_data *pd;
+ int rc, cpu;
ENTRY;
- 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 == 0) {
- EXIT;
- return;
- }
-
- LL_CDEBUG_PAGE(D_PAGE, page, "being evicted\n");
-
- exp = ll_i2obdexp(inode);
+ 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));
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)
/* 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_lock);
- if (!list_empty(&llap->llap_proc_item))
- list_del_init(&llap->llap_proc_item);
- sbi->ll_pglist_gen++;
- spin_unlock(&sbi->ll_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_GROUP_LOCKED)
- RETURN(1);
-
- 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(!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;
+ }
+
+ 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,
struct ll_async_page *llap,
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 | ASYNC_READY
- | ASYNC_URGENT);
+ 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);
RETURN(rc);
}
+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_ra_stats_inc(struct address_space *mapping, enum ra_stat which)
+{
+ struct ll_sb_info *sbi = ll_i2sbi(mapping->host);
+ ll_ra_stats_inc_sbi(sbi, which);
+}
+
+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 c %lu ws %lu wl %lu nra %lu\n", \
- ras->ras_last_readpage, ras->ras_consecutive, \
- ras->ras_window_start, ras->ras_window_len, \
- ras->ras_next_readahead);
+ 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;
+
+ list_add(&rar->lrr_linkage, &ras->ras_read_beads);
+ spin_unlock(&ras->ras_lock);
+}
+
+void ll_ra_read_ex(struct file *f, struct ll_ra_read *rar)
+{
+ struct ll_readahead_state *ras;
+
+ ras = ll_ras_get(f);
+
+ spin_lock(&ras->ras_lock);
+ list_del_init(&rar->lrr_linkage);
+ spin_unlock(&ras->ras_lock);
+}
+
+static struct ll_ra_read *ll_ra_read_get_locked(struct ll_readahead_state *ras)
+{
+ struct ll_ra_read *scan;
+
+ 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);
+ }
+
+ /* skip completed pages */
+ if (Page_Uptodate(page))
+ GOTO(unlock_page, rc = 0);
+
+ /* 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;
+}
+
+/* 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;
+ }
+ }
+ }
+ *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 i, start = 0, end = 0, reserved;
- struct ll_async_page *llap;
- struct page *page;
- int rc, ret = 0;
+ 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;
- kms = lov_merge_size(ll_i2info(mapping->host)->lli_smd, 1);
- if (kms == 0)
+ 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;
- end = min(end, (unsigned long)(kms >> PAGE_CACHE_SHIFT));
+ }
+ 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)
+ 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(mapping->host), end - start + 1);
+ reserved = ll_ra_count_get(ll_i2sbi(inode), len);
- for (i = start; reserved > 0 && i <= end; i++) {
- /* skip locked pages from previous readpage calls */
- page = grab_cache_page_nowait(mapping, i);
- if (page == NULL) {
- CDEBUG(D_READA, "g_c_p_n failed\n");
- continue;
- }
-
- /* we do this first so that we can see the page in the /proc
- * accounting */
- llap = llap_from_page(page);
- if (IS_ERR(llap) || llap->llap_defer_uptodate)
- goto next_page;
-
- /* skip completed pages */
- if (Page_Uptodate(page))
- goto next_page;
-
- /* bail when we hit the end of the lock. */
- if ((rc = ll_page_matches(page, flags)) <= 0) {
- LL_CDEBUG_PAGE(D_READA | D_PAGE, page,
- "lock match failed: rc %d\n", rc);
- i = end;
- goto next_page;
- }
+ if (reserved < len)
+ ll_ra_stats_inc(mapping, RA_STAT_MAX_IN_FLIGHT);
- rc = ll_issue_page_read(exp, llap, oig, 1);
- if (rc == 0) {
- reserved--;
- ret++;
- LL_CDEBUG_PAGE(D_READA| D_PAGE, page,
- "started read-ahead\n");
- }
- if (rc) {
- next_page:
- LL_CDEBUG_PAGE(D_READA | D_PAGE, page,
- "skipping read-ahead\n");
+ CDEBUG(D_READA, "reserved page %lu \n", reserved);
+
+ ret = ll_read_ahead_pages(exp, oig, &ria, &reserved, mapping, &ra_end);
- unlock_page(page);
+ 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);
}
- page_cache_release(page);
+ spin_unlock(&ras->ras_lock);
}
- LASSERTF(reserved >= 0, "reserved %lu\n", reserved);
- if (reserved != 0)
- ll_ra_count_put(ll_i2sbi(mapping->host), reserved);
RETURN(ret);
}
-static void ras_set_start(struct ll_readahead_state *ras,
- unsigned long index)
+static void ras_set_start(struct ll_readahead_state *ras, unsigned long index)
{
- ras->ras_window_start = index & (~(PTLRPC_MAX_BRW_PAGES - 1));
- ras->ras_next_readahead = max(ras->ras_window_start,
- ras->ras_next_readahead);
+ 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)
+static void ras_reset(struct ll_readahead_state *ras, unsigned long index)
{
ras->ras_last_readpage = index;
- ras->ras_consecutive = 1;
+ ras->ras_consecutive_requests = 0;
+ ras->ras_consecutive_pages = 0;
ras->ras_window_len = 0;
ras_set_start(ras, index);
- ras->ras_next_readahead = ras->ras_window_start;
+ 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 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);
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 ras_update(struct ll_readahead_state *ras,
- unsigned long index, unsigned long max)
+/* Set stride I/O read-ahead window start offset */
+static void ras_set_stride_offset(struct ll_readahead_state *ras)
{
+ 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);
- if (index != ras->ras_last_readpage + 1) {
- ras_reset(ras, index);
- GOTO(out_unlock, 0);
+ 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++;
+ 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);
- if (ras->ras_consecutive == 2) {
- ras->ras_window_len = PTLRPC_MAX_BRW_PAGES;
+ /* 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);
}
- /* we need to increase the window sometimes. we'll arbitrarily
- * do it half-way through the pages in an rpc */
- if ((index & (PTLRPC_MAX_BRW_PAGES - 1)) ==
- (PTLRPC_MAX_BRW_PAGES >> 1)) {
- ras->ras_window_len += PTLRPC_MAX_BRW_PAGES;
- ras->ras_window_len = min(ras->ras_window_len, max);
+ /* 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);
+}
+
/*
* for now we do our readpage the same on both 2.4 and 2.5. The kernel's
* read-ahead assumes it is valid to issue readpage all the way up to
*/
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 (ll_i2sbi(inode)->ll_flags & LL_SBI_READAHEAD)
- ras_update(&fd->fd_ras, page->index,
- ll_i2sbi(inode)->ll_max_read_ahead_pages);
if (llap->llap_defer_uptodate) {
+ /* 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,
+ 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);
GOTO(out_oig, rc = 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)) {
- 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);
- 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)
+ /* 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);
oig_release(oig);
RETURN(rc);
}
+
+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;
+ loff_t org_pos = pos;
+ obd_flag brw_flags;
+ int rc;
+ int i;
+ ENTRY;
+
+ 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);
+}
+
+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;
+
+ 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);
+}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff