Add initial support for striping target, hardcode maximal number of stripes

to 2 for now. strategy routine must be written, for now only parsing and
support routines are available. This is work in progress code and should be
taken very carefully.

sys/dev/dm/dm.h

@@ -1,4 +1,4 @@
-/*        $NetBSD: dm.h,v 1.9 2009/02/19 23:07:32 haad Exp $      */
+/*        $NetBSD: dm.h,v 1.10 2009/03/01 23:15:56 haad Exp $      */
 
 /*
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -163,6 +163,14 @@ typedef struct target_linear_config {
 	uint64_t offset;
 } dm_target_linear_config_t;
 
+/* for stripe : */
+typedef struct target_stripe_config {
+#define MAX_STRIPES 2
+	struct target_linear_config stripe_devs[MAX_STRIPES];
+	uint8_t stripe_num;
+	uint64_t stripe_chunksize;
+	size_t params_len;
+} dm_target_stripe_config_t;
 
 /* for mirror : */
 typedef struct target_mirror_config {

sys/dev/dm/dm_target_stripe.c

@@ -1,4 +1,4 @@
-/*$NetBSD: dm_target_stripe.c,v 1.2 2009/01/02 22:33:51 haad Exp $*/
+/*$NetBSD: dm_target_stripe.c,v 1.3 2009/03/01 23:15:56 haad Exp $*/
 
 /*
  * Copyright (c) 2009 The NetBSD Foundation, Inc.
@@ -36,6 +36,8 @@
 #include <sys/param.h>
 
 #include <sys/buf.h>
+#include <sys/kmem.h>
+#include <sys/vnode.h>
 
 #include "dm.h"
 
@@ -61,9 +63,11 @@ dm_target_stripe_modcmd(modcmd_t cmd, void *arg)
 	
 	switch (cmd) {
 	case MODULE_CMD_INIT:
-		if ((dmt = dm_target_lookup("stripe")) != NULL)
+		if ((dmt = dm_target_lookup("stripe")) != NULL) {
+			dm_target_unbusy(dmt);
 			return EEXIST;
-
+		}
+		
 		dmt = dm_target_alloc("stripe");
 		
 		dmt->version[0] = 1;
@@ -97,34 +101,94 @@ dm_target_stripe_modcmd(modcmd_t cmd, void *arg)
 
 #endif
 
-/* Init function called from dm_table_load_ioctl. */
+/*
+ * Init function called from dm_table_load_ioctl.
+ * Example line sent to dm from lvm tools when using striped target.
+ * start length striped #stripes chunk_size device1 offset1 ... deviceN offsetN
+ * 0 65536 striped 2 512 /dev/hda 0 /dev/hdb 0
+ */
 int
-dm_target_stripe_init(dm_dev_t *dmv, void **target_config, char *argv)
+dm_target_stripe_init(dm_dev_t *dmv, void **target_config, char *params)
 {
+	dm_target_stripe_config_t *tsc;
+	size_t len;
+	char **ap, *argv[10];
 
+	if(params == NULL)
+		return EINVAL;
+
+	len = strlen(params) + 1;
+	
+	/*
+	 * Parse a string, containing tokens delimited by white space,
+	 * into an argument vector
+	 */
+	for (ap = argv; ap < &argv[9] &&
+		 (*ap = strsep(&params, " \t")) != NULL;) {
+		if (**ap != '\0')
+			ap++;
+	}
+	
 	printf("Stripe target init function called!!\n");
 
-	*target_config = NULL;
+	printf("Stripe target chunk size %s number of stripes %s\n", argv[1], argv[0]);
+	printf("Stripe target device name %s -- offset %s\n", argv[2], argv[3]);
+	printf("Stripe target device name %s -- offset %s\n", argv[4], argv[5]);
+
+	if (atoi(argv[0]) > MAX_STRIPES)
+		return ENOTSUP;
+
+	if ((tsc = kmem_alloc(sizeof(dm_target_stripe_config_t), KM_NOSLEEP))
+	    == NULL)
+		return ENOMEM;
+	
+	/* Insert dmp to global pdev list */
+	if ((tsc->stripe_devs[0].pdev = dm_pdev_insert(argv[2])) == NULL)
+		return ENOENT;
+
+	/* Insert dmp to global pdev list */
+	if ((tsc->stripe_devs[1].pdev = dm_pdev_insert(argv[4])) == NULL)
+		return ENOENT;
+
+	tsc->stripe_devs[0].offset = atoi(argv[3]);
+	tsc->stripe_devs[1].offset = atoi(argv[5]);
+
+	/* Save length of param string */
+	tsc->params_len = len;
+	tsc->stripe_chunksize = atoi(argv[1]);
+	tsc->stripe_num = (uint8_t)atoi(argv[0]);
+	
+	*target_config = tsc;
 
 	dmv->dev_type = DM_STRIPE_DEV;
 	
-	return ENOSYS;
+	return 0;
 }
 
 /* Status routine called to get params string. */
 char *
 dm_target_stripe_status(void *target_config)
 {
-	return NULL;
+	dm_target_stripe_config_t *tsc;
+	char *params;
+
+	tsc = target_config;
+	
+	if ((params = kmem_alloc(tsc->params_len, KM_NOSLEEP)) == NULL)
+		return NULL;
+
+	snprintf(params, tsc->params_len, "%d %lld %s %lld %s %lld", tsc->stripe_num, tsc->stripe_chunksize,
+	    tsc->stripe_devs[0].pdev->name, tsc->stripe_devs[0].offset,
+	    tsc->stripe_devs[1].pdev->name, tsc->stripe_devs[1].offset);
+	
+	return params;
 }	
 
 /* Strategy routine called from dm_strategy. */
 int
 dm_target_stripe_strategy(dm_table_entry_t *table_en, struct buf *bp)
 {
-
-	printf("Stripe target read function called!!\n");
-
+	
 	bp->b_error = EIO;
 	bp->b_resid = 0;
 
@@ -137,11 +201,23 @@ dm_target_stripe_strategy(dm_table_entry_t *table_en, struct buf *bp)
 int
 dm_target_stripe_destroy(dm_table_entry_t *table_en)
 {
-	table_en->target_config = NULL;
+	dm_target_stripe_config_t *tsc;
+		
+	tsc = table_en->target_config;
+
+	if (tsc == NULL)
+		return 0;
+	
+	dm_pdev_decr(tsc->stripe_devs[0].pdev);
+	dm_pdev_decr(tsc->stripe_devs[1].pdev);
 
 	/* Unbusy target so we can unload it */
 	dm_target_unbusy(table_en->target);
 	
+	kmem_free(tsc, sizeof(dm_target_stripe_config_t));
+	
+	table_en->target_config = NULL;
+
 	return 0;
 }
 
@@ -149,6 +225,26 @@ dm_target_stripe_destroy(dm_table_entry_t *table_en)
 int
 dm_target_stripe_deps(dm_table_entry_t *table_en, prop_array_t prop_array)
 {	
+	dm_target_stripe_config_t *tsc;
+	struct vattr va;
+	
+	int error;
+	
+	if (table_en->target_config == NULL)
+		return ENOENT;
+	
+	tsc = table_en->target_config;
+	
+	if ((error = VOP_GETATTR(tsc->stripe_devs[0].pdev->pdev_vnode, &va, curlwp->l_cred)) != 0)
+		return error;
+
+	prop_array_add_uint64(prop_array, (uint64_t)va.va_rdev);
+	
+	if ((error = VOP_GETATTR(tsc->stripe_devs[1].pdev->pdev_vnode, &va, curlwp->l_cred)) != 0)
+		return error;
+	
+	prop_array_add_uint64(prop_array, (uint64_t)va.va_rdev);
+	
 	return 0;
 }