dm: rename multipath path selector source files to have "dm-ps" prefix

Additional prefix helps clarify that these source files implement path
selectors.

Required updating Makefile to still build modules _without_ the
"dm-ps" prefix to preserve dm-multipath's ability to autoload path
selector modules. While at it, cleaned up some DM whitespace in
Makefile.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 0 insertions, 283 deletions

diff --git a/drivers/md/dm-queue-length.c b/drivers/md/dm-queue-length.c
deleted file mode 100644
index 5fd018d18418..000000000000
--- a/drivers/md/dm-queue-length.c
+++ /dev/null
@@ -1,283 +0,0 @@
-/*
- * Copyright (C) 2004-2005 IBM Corp.  All Rights Reserved.
- * Copyright (C) 2006-2009 NEC Corporation.
- *
- * dm-queue-length.c
- *
- * Module Author: Stefan Bader, IBM
- * Modified by: Kiyoshi Ueda, NEC
- *
- * This file is released under the GPL.
- *
- * queue-length path selector - choose a path with the least number of
- * in-flight I/Os.
- */
-
-#include "dm.h"
-#include "dm-path-selector.h"
-
-#include <linux/slab.h>
-#include <linux/ctype.h>
-#include <linux/errno.h>
-#include <linux/module.h>
-#include <linux/atomic.h>
-
-#define DM_MSG_PREFIX	"multipath queue-length"
-#define QL_MIN_IO	1
-#define QL_VERSION	"0.2.0"
-
-struct selector {
-	struct list_head	valid_paths;
-	struct list_head	failed_paths;
-	spinlock_t lock;
-};
-
-struct path_info {
-	struct list_head	list;
-	struct dm_path		*path;
-	unsigned		repeat_count;
-	atomic_t		qlen;	/* the number of in-flight I/Os */
-};
-
-static struct selector *alloc_selector(void)
-{
-	struct selector *s = kmalloc(sizeof(*s), GFP_KERNEL);
-
-	if (s) {
-		INIT_LIST_HEAD(&s->valid_paths);
-		INIT_LIST_HEAD(&s->failed_paths);
-		spin_lock_init(&s->lock);
-	}
-
-	return s;
-}
-
-static int ql_create(struct path_selector *ps, unsigned argc, char **argv)
-{
-	struct selector *s = alloc_selector();
-
-	if (!s)
-		return -ENOMEM;
-
-	ps->context = s;
-	return 0;
-}
-
-static void ql_free_paths(struct list_head *paths)
-{
-	struct path_info *pi, *next;
-
-	list_for_each_entry_safe(pi, next, paths, list) {
-		list_del(&pi->list);
-		kfree(pi);
-	}
-}
-
-static void ql_destroy(struct path_selector *ps)
-{
-	struct selector *s = ps->context;
-
-	ql_free_paths(&s->valid_paths);
-	ql_free_paths(&s->failed_paths);
-	kfree(s);
-	ps->context = NULL;
-}
-
-static int ql_status(struct path_selector *ps, struct dm_path *path,
-		     status_type_t type, char *result, unsigned maxlen)
-{
-	unsigned sz = 0;
-	struct path_info *pi;
-
-	/* When called with NULL path, return selector status/args. */
-	if (!path)
-		DMEMIT("0 ");
-	else {
-		pi = path->pscontext;
-
-		switch (type) {
-		case STATUSTYPE_INFO:
-			DMEMIT("%d ", atomic_read(&pi->qlen));
-			break;
-		case STATUSTYPE_TABLE:
-			DMEMIT("%u ", pi->repeat_count);
-			break;
-		}
-	}
-
-	return sz;
-}
-
-static int ql_add_path(struct path_selector *ps, struct dm_path *path,
-		       int argc, char **argv, char **error)
-{
-	struct selector *s = ps->context;
-	struct path_info *pi;
-	unsigned repeat_count = QL_MIN_IO;
-	char dummy;
-	unsigned long flags;
-
-	/*
-	 * Arguments: [<repeat_count>]
-	 * 	<repeat_count>: The number of I/Os before switching path.
-	 * 			If not given, default (QL_MIN_IO) is used.
-	 */
-	if (argc > 1) {
-		*error = "queue-length ps: incorrect number of arguments";
-		return -EINVAL;
-	}
-
-	if ((argc == 1) && (sscanf(argv[0], "%u%c", &repeat_count, &dummy) != 1)) {
-		*error = "queue-length ps: invalid repeat count";
-		return -EINVAL;
-	}
-
-	if (repeat_count > 1) {
-		DMWARN_LIMIT("repeat_count > 1 is deprecated, using 1 instead");
-		repeat_count = 1;
-	}
-
-	/* Allocate the path information structure */
-	pi = kmalloc(sizeof(*pi), GFP_KERNEL);
-	if (!pi) {
-		*error = "queue-length ps: Error allocating path information";
-		return -ENOMEM;
-	}
-
-	pi->path = path;
-	pi->repeat_count = repeat_count;
-	atomic_set(&pi->qlen, 0);
-
-	path->pscontext = pi;
-
-	spin_lock_irqsave(&s->lock, flags);
-	list_add_tail(&pi->list, &s->valid_paths);
-	spin_unlock_irqrestore(&s->lock, flags);
-
-	return 0;
-}
-
-static void ql_fail_path(struct path_selector *ps, struct dm_path *path)
-{
-	struct selector *s = ps->context;
-	struct path_info *pi = path->pscontext;
-	unsigned long flags;
-
-	spin_lock_irqsave(&s->lock, flags);
-	list_move(&pi->list, &s->failed_paths);
-	spin_unlock_irqrestore(&s->lock, flags);
-}
-
-static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)
-{
-	struct selector *s = ps->context;
-	struct path_info *pi = path->pscontext;
-	unsigned long flags;
-
-	spin_lock_irqsave(&s->lock, flags);
-	list_move_tail(&pi->list, &s->valid_paths);
-	spin_unlock_irqrestore(&s->lock, flags);
-
-	return 0;
-}
-
-/*
- * Select a path having the minimum number of in-flight I/Os
- */
-static struct dm_path *ql_select_path(struct path_selector *ps, size_t nr_bytes)
-{
-	struct selector *s = ps->context;
-	struct path_info *pi = NULL, *best = NULL;
-	struct dm_path *ret = NULL;
-	unsigned long flags;
-
-	spin_lock_irqsave(&s->lock, flags);
-	if (list_empty(&s->valid_paths))
-		goto out;
-
-	list_for_each_entry(pi, &s->valid_paths, list) {
-		if (!best ||
-		    (atomic_read(&pi->qlen) < atomic_read(&best->qlen)))
-			best = pi;
-
-		if (!atomic_read(&best->qlen))
-			break;
-	}
-
-	if (!best)
-		goto out;
-
-	/* Move most recently used to least preferred to evenly balance. */
-	list_move_tail(&best->list, &s->valid_paths);
-
-	ret = best->path;
-out:
-	spin_unlock_irqrestore(&s->lock, flags);
-	return ret;
-}
-
-static int ql_start_io(struct path_selector *ps, struct dm_path *path,
-		       size_t nr_bytes)
-{
-	struct path_info *pi = path->pscontext;
-
-	atomic_inc(&pi->qlen);
-
-	return 0;
-}
-
-static int ql_end_io(struct path_selector *ps, struct dm_path *path,
-		     size_t nr_bytes, u64 start_time)
-{
-	struct path_info *pi = path->pscontext;
-
-	atomic_dec(&pi->qlen);
-
-	return 0;
-}
-
-static struct path_selector_type ql_ps = {
-	.name		= "queue-length",
-	.module		= THIS_MODULE,
-	.table_args	= 1,
-	.info_args	= 1,
-	.create		= ql_create,
-	.destroy	= ql_destroy,
-	.status		= ql_status,
-	.add_path	= ql_add_path,
-	.fail_path	= ql_fail_path,
-	.reinstate_path	= ql_reinstate_path,
-	.select_path	= ql_select_path,
-	.start_io	= ql_start_io,
-	.end_io		= ql_end_io,
-};
-
-static int __init dm_ql_init(void)
-{
-	int r = dm_register_path_selector(&ql_ps);
-
-	if (r < 0)
-		DMERR("register failed %d", r);
-
-	DMINFO("version " QL_VERSION " loaded");
-
-	return r;
-}
-
-static void __exit dm_ql_exit(void)
-{
-	int r = dm_unregister_path_selector(&ql_ps);
-
-	if (r < 0)
-		DMERR("unregister failed %d", r);
-}
-
-module_init(dm_ql_init);
-module_exit(dm_ql_exit);
-
-MODULE_AUTHOR("Stefan Bader <Stefan.Bader at de.ibm.com>");
-MODULE_DESCRIPTION(
-	"(C) Copyright IBM Corp. 2004,2005   All Rights Reserved.\n"
-	DM_NAME " path selector to balance the number of in-flight I/Os"
-);
-MODULE_LICENSE("GPL");