X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Flov%2Flov_page.c;h=44031d293e9c38e639b6d5454734d1ff10978176;hb=a0bdb01ad05b24d2469e715ec2ce7f774d31d2e1;hp=35e1d1a1f4b5cbfd1c40212bd3b5aac1c2765e70;hpb=2b294992edce5af7b79d4300ed3aa1ea6a8db850;p=fs%2Flustre-release.git

diff --git a/lustre/lov/lov_page.c b/lustre/lov/lov_page.c
index 35e1d1a..44031d2 100644
--- a/lustre/lov/lov_page.c
+++ b/lustre/lov/lov_page.c
@@ -15,11 +15,7 @@
  *
  * 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
- *
- * 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.
+ * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
@@ -27,11 +23,10 @@
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
- * Copyright (c) 2011, 2014, Intel Corporation.
+ * Copyright (c) 2011, 2017, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
- * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * Implementation of cl_page for LOV layer.
  *
@@ -42,6 +37,8 @@
 #define DEBUG_SUBSYSTEM S_LOV
 
 #include "lov_cl_internal.h"
+#include <linux/bug.h>
+#include <linux/compiler.h>
 
 /** \addtogroup lov
  *  @{
@@ -52,140 +49,111 @@
  * Lov page operations.
  *
  */
-
-/**
- * Adjust the stripe index by layout of raid0. @max_index is the maximum
- * page index covered by an underlying DLM lock.
- * This function converts max_index from stripe level to file level, and make
- * sure it's not beyond one stripe.
- */
-static int lov_raid0_page_is_under_lock(const struct lu_env *env,
-					const struct cl_page_slice *slice,
-					struct cl_io *unused,
-					pgoff_t *max_index)
+int lov_page_init_composite(const struct lu_env *env, struct cl_object *obj,
+			    struct cl_page *page, pgoff_t index)
 {
-	struct lov_object *loo = cl2lov(slice->cpl_obj);
-	struct lov_layout_raid0 *r0 = lov_r0(loo);
-	pgoff_t index = *max_index;
-	unsigned int pps; /* pages per stripe */
-	ENTRY;
+	struct lov_object *loo = cl2lov(obj);
+	struct lov_io *lio = lov_env_io(env);
+	struct cl_object *subobj;
+	struct cl_object *o;
+	struct lov_io_sub *sub;
+	struct lov_layout_raid0 *r0;
+	loff_t offset;
+	loff_t suboff;
+	bool stripe_cached = false;
+	int entry;
+	int stripe;
+	int rc;
 
-	CDEBUG(D_READA, DFID "*max_index = %lu, nr = %d\n",
-	       PFID(lu_object_fid(lov2lu(loo))), index, r0->lo_nr);
+	ENTRY;
 
-	if (index == 0) /* the page is not covered by any lock */
-		RETURN(0);
+	/* Direct i/o (CPT_TRANSIENT) is split strictly to stripes, so we can
+	 * cache the stripe information.  Buffered i/o is differently
+	 * organized, and stripe calculation isn't a significant cost for
+	 * buffered i/o, so we only cache this for direct i/o.
+	 */
+	stripe_cached = lio->lis_cached_entry != LIS_CACHE_ENTRY_NONE &&
+			page->cp_type == CPT_TRANSIENT;
 
-	if (r0->lo_nr == 1) /* single stripe file */
-		RETURN(0);
+	offset = cl_offset(obj, index);
 
-	/* max_index is stripe level, convert it into file level */
-	if (index != CL_PAGE_EOF) {
-		int stripeno = lov_page_stripe(slice->cpl_page);
-		*max_index = lov_stripe_pgoff(loo->lo_lsm, index, stripeno);
+	if (stripe_cached) {
+		entry = lio->lis_cached_entry;
+		stripe = lio->lis_cached_stripe;
+		/* Offset can never go backwards in an i/o, so this is valid */
+		suboff = lio->lis_cached_suboff + offset - lio->lis_cached_off;
+	} else {
+		entry = lov_io_layout_at(lio, offset);
+
+		stripe = lov_stripe_number(loo->lo_lsm, entry, offset);
+		rc = lov_stripe_offset(loo->lo_lsm, entry, offset, stripe,
+				       &suboff);
+		LASSERT(rc == 0);
+		lio->lis_cached_entry = entry;
+		lio->lis_cached_stripe = stripe;
+		lio->lis_cached_off = offset;
+		lio->lis_cached_suboff = suboff;
 	}
 
-	/* calculate the end of current stripe */
-	pps = loo->lo_lsm->lsm_stripe_size >> PAGE_CACHE_SHIFT;
-	index = slice->cpl_index + pps - slice->cpl_index % pps - 1;
-
-	CDEBUG(D_READA, DFID "*max_index = %lu, index = %lu, pps = %u, "
-	       "stripe_size = %u, stripe no = %u, page index = %lu\n",
-	       PFID(lu_object_fid(lov2lu(loo))), *max_index, index, pps,
-	       loo->lo_lsm->lsm_stripe_size, lov_page_stripe(slice->cpl_page),
-	       slice->cpl_index);
-
-	/* never exceed the end of the stripe */
-	*max_index = min_t(pgoff_t, *max_index, index);
-	RETURN(0);
-}
+	if (entry < 0 || !lsm_entry_inited(loo->lo_lsm, entry)) {
+		/* non-existing layout component */
+		lov_page_init_empty(env, obj, page, index);
+		RETURN(0);
+	}
 
-static int lov_raid0_page_print(const struct lu_env *env,
-				const struct cl_page_slice *slice,
-				void *cookie, lu_printer_t printer)
-{
-	struct lov_page *lp = cl2lov_page(slice);
+	CDEBUG(D_PAGE, "offset %llu, entry %d, stripe %d, suboff %llu\n",
+	       offset, entry, stripe, suboff);
 
-	return (*printer)(env, cookie, LUSTRE_LOV_NAME"-page@%p, raid0\n", lp);
-}
+	page->cp_lov_index = lov_comp_index(entry, stripe);
+	LASSERT(page->cp_lov_index != CP_LOV_INDEX_EMPTY);
 
-static const struct cl_page_operations lov_raid0_page_ops = {
-	.cpo_is_under_lock = lov_raid0_page_is_under_lock,
-	.cpo_print = lov_raid0_page_print
-};
+	if (!stripe_cached) {
+		sub = lov_sub_get(env, lio, page->cp_lov_index);
+		if (IS_ERR(sub))
+			RETURN(PTR_ERR(sub));
+	} else {
+		sub = lio->lis_cached_sub;
+	}
 
-int lov_page_init_raid0(const struct lu_env *env, struct cl_object *obj,
-			struct cl_page *page, pgoff_t index)
-{
-	struct lov_object *loo = cl2lov(obj);
-	struct lov_layout_raid0 *r0 = lov_r0(loo);
-	struct lov_io     *lio = lov_env_io(env);
-	struct cl_object  *subobj;
-	struct cl_object  *o;
-	struct lov_io_sub *sub;
-	struct lov_page   *lpg = cl_object_page_slice(obj, page);
-	loff_t             offset;
-	obd_off            suboff;
-	int                stripe;
-	int                rc;
-	ENTRY;
+	lio->lis_cached_sub = sub;
 
-	offset = cl_offset(obj, index);
-	stripe = lov_stripe_number(loo->lo_lsm, offset);
+	r0 = lov_r0(loo, entry);
 	LASSERT(stripe < r0->lo_nr);
-	rc = lov_stripe_offset(loo->lo_lsm, offset, stripe,
-			       &suboff);
-	LASSERT(rc == 0);
-
-	lpg->lps_stripe = stripe;
-	cl_page_slice_add(page, &lpg->lps_cl, obj, index, &lov_raid0_page_ops);
-
-	sub = lov_sub_get(env, lio, stripe);
-	if (IS_ERR(sub))
-		RETURN(PTR_ERR(sub));
 
 	subobj = lovsub2cl(r0->lo_sub[stripe]);
-	list_for_each_entry(o, &subobj->co_lu.lo_header->loh_layers,
-			    co_lu.lo_linkage) {
-		if (o->co_ops->coo_page_init != NULL) {
+	cl_object_for_each(o, subobj) {
+		if (o->co_ops->coo_page_init) {
 			rc = o->co_ops->coo_page_init(sub->sub_env, o, page,
 						      cl_index(subobj, suboff));
 			if (rc != 0)
 				break;
 		}
 	}
-	lov_sub_put(sub);
-	RETURN(rc);
-}
 
-static int lov_empty_page_print(const struct lu_env *env,
-				const struct cl_page_slice *slice,
-				void *cookie, lu_printer_t printer)
-{
-        struct lov_page *lp = cl2lov_page(slice);
-
-        return (*printer)(env, cookie, LUSTRE_LOV_NAME"-page@%p, empty.\n", lp);
+	RETURN(rc);
 }
 
-static const struct cl_page_operations lov_empty_page_ops = {
-	.cpo_print = lov_empty_page_print
-};
-
 int lov_page_init_empty(const struct lu_env *env, struct cl_object *obj,
 			struct cl_page *page, pgoff_t index)
 {
-	struct lov_page *lpg = cl_object_page_slice(obj, page);
 	void *addr;
+
 	ENTRY;
+	BUILD_BUG_ON(!__same_type(page->cp_lov_index, CP_LOV_INDEX_EMPTY));
+	page->cp_lov_index = CP_LOV_INDEX_EMPTY;
 
-	cl_page_slice_add(page, &lpg->lps_cl, obj, index, &lov_empty_page_ops);
 	addr = kmap(page->cp_vmpage);
 	memset(addr, 0, cl_page_size(obj));
 	kunmap(page->cp_vmpage);
-	cl_page_export(env, page, 1);
+	SetPageUptodate(page->cp_vmpage);
 	RETURN(0);
 }
 
+int lov_page_init_foreign(const struct lu_env *env, struct cl_object *obj,
+			struct cl_page *page, pgoff_t index)
+{
+	CDEBUG(D_PAGE, DFID" has no data\n", PFID(lu_object_fid(&obj->co_lu)));
+	RETURN(-ENODATA);
+}
 
 /** @} lov */
-