NetBSD/sys/dev/dm/dm_target_stripe.c

311 lines
8.4 KiB
C

/*$NetBSD: dm_target_stripe.c,v 1.7 2009/09/09 22:38:49 haad Exp $*/
/*
* Copyright (c) 2009 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Adam Hamsik.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This file implements initial version of device-mapper stripe target.
*/
#include <sys/types.h>
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/kmem.h>
#include <sys/vnode.h>
#include "dm.h"
#include "netbsd-dm.h"
#ifdef DM_TARGET_MODULE
/*
* Every target can be compiled directly to dm driver or as a
* separate module this part of target is used for loading targets
* to dm driver.
* Target can be unloaded from kernel only if there are no users of
* it e.g. there are no devices which uses that target.
*/
#include <sys/kernel.h>
#include <sys/module.h>
MODULE(MODULE_CLASS_MISC, dm_target_stripe, NULL);
static int
dm_target_stripe_modcmd(modcmd_t cmd, void *arg)
{
dm_target_t *dmt;
int r;
dmt = NULL;
switch (cmd) {
case MODULE_CMD_INIT:
if ((dmt = dm_target_lookup("stripe")) != NULL) {
dm_target_unbusy(dmt);
return EEXIST;
}
dmt = dm_target_alloc("stripe");
dmt->version[0] = 1;
dmt->version[1] = 0;
dmt->version[2] = 0;
strlcpy(dmt->name, "stripe", DM_MAX_TYPE_NAME);
dmt->init = &dm_target_stripe_init;
dmt->status = &dm_target_stripe_status;
dmt->strategy = &dm_target_stripe_strategy;
dmt->deps = &dm_target_stripe_deps;
dmt->destroy = &dm_target_stripe_destroy;
dmt->upcall = &dm_target_stripe_upcall;
r = dm_target_insert(dmt);
break;
case MODULE_CMD_FINI:
r = dm_target_rem("stripe");
break;
case MODULE_CMD_STAT:
return ENOTTY;
default:
return ENOTTY;
}
return r;
}
#endif
/*
* 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, prop_dictionary_t dict)
{
dm_target_stripe_config_t *tsc;
prop_array_t dev_array;
prop_dictionary_t dev_dict1, dev_dict2;
uint64_t stripes, chunk_size, offset1, offset2;
const char *device1, *device2;
if (prop_dictionary_get_uint64(dict, DM_TARGET_STRIPE_STRIPES,
&stripes) == false)
return EINVAL;
if (prop_dictionary_get_uint64(dict, DM_TARGET_STRIPE_CHUNKSIZE,
&chunk_size) == false)
return EINVAL;
dev_array = prop_dictionary_get(dict, DM_TARGET_STRIPE_DEVARRAY);
/* XXX Support for more than 2 devices */
dev_dict1 = prop_array_get(dev_array, 0);
dev_dict2 = prop_array_get(dev_array, 1);
if(dev_dict2 == NULL || dev_dict1 == NULL)
return EINVAL;
prop_dictionary_get_cstring_nocopy(dev_dict1, DM_TARGET_STRIPE_DEVICE, &device1);
prop_dictionary_get_uint64(dev_dict1, DM_TARGET_STRIPE_OFFSET, &offset1);
prop_dictionary_get_cstring_nocopy(dev_dict2, DM_TARGET_STRIPE_DEVICE, &device2);
prop_dictionary_get_uint64(dev_dict2, DM_TARGET_STRIPE_OFFSET, &offset2);
aprint_debug("Stripe target init function called!!\n");
aprint_debug("Stripe target chunk size %"PRIu64" number of stripes %"PRIu64"\n", chunk_size, stripes);
aprint_debug("Stripe target device name %s -- offset %"PRIu64"\n", device1, offset1);
aprint_debug("Stripe target device name %s -- offset %"PRIu64"\n", device2, offset2);
if (stripes > 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(device1)) == NULL)
return ENOENT;
/* Insert dmp to global pdev list */
if ((tsc->stripe_devs[1].pdev = dm_pdev_insert(device2)) == NULL)
return ENOENT;
tsc->stripe_devs[0].offset = offset1;
tsc->stripe_devs[1].offset = offset2;
tsc->stripe_chunksize = chunk_size;
tsc->stripe_num = (uint8_t)stripes;
*target_config = tsc;
dmv->dev_type = DM_STRIPE_DEV;
return 0;
}
/* Status routine called to get params string. */
char *
dm_target_stripe_status(void *target_config)
{
dm_target_stripe_config_t *tsc;
char *params;
tsc = target_config;
if ((params = kmem_alloc(DM_MAX_PARAMS_SIZE, KM_SLEEP)) == NULL)
return NULL;
snprintf(params, DM_MAX_PARAMS_SIZE, "%d %"PRIu64" %s %"PRIu64" %s %"PRIu64,
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)
{
dm_target_stripe_config_t *tsc;
struct buf *nestbuf;
uint64_t blkno, blkoff;
uint64_t stripe, stripe_blknr;
uint32_t stripe_off, stripe_rest, num_blks, issue_blks;
int stripe_devnr;
tsc = table_en->target_config;
if (tsc == NULL)
return 0;
/* aprint_debug("Stripe target read function called %" PRIu64 "!!\n",
tlc->offset);*/
/* calculate extent of request */
KASSERT(bp->b_resid % DEV_BSIZE == 0);
blkno = bp->b_blkno;
blkoff = 0;
num_blks = bp->b_resid / DEV_BSIZE;
for (;;) {
/* blockno to strip piece nr */
stripe = blkno / tsc->stripe_chunksize;
stripe_off = blkno % tsc->stripe_chunksize;
/* where we are inside the strip */
stripe_devnr = stripe % tsc->stripe_num;
stripe_blknr = stripe / tsc->stripe_num;
/* how much is left before we hit a boundary */
stripe_rest = tsc->stripe_chunksize - stripe_off;
/* issue this piece on stripe `stripe' */
issue_blks = MIN(stripe_rest, num_blks);
nestbuf = getiobuf(NULL, true);
nestiobuf_setup(bp, nestbuf, blkoff, issue_blks * DEV_BSIZE);
nestbuf->b_blkno = stripe_blknr * tsc->stripe_chunksize + stripe_off;
nestbuf->b_blkno += tsc->stripe_devs[stripe_devnr].offset;
VOP_STRATEGY(tsc->stripe_devs[stripe_devnr].pdev->pdev_vnode, nestbuf);
blkno += issue_blks;
blkoff += issue_blks * DEV_BSIZE;
num_blks -= issue_blks;
if (num_blks <= 0)
break;
}
return 0;
}
/* Doesn't do anything here. */
int
dm_target_stripe_destroy(dm_table_entry_t *table_en)
{
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;
}
/* Doesn't not need to do anything here. */
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;
}
/* Unsupported for this target. */
int
dm_target_stripe_upcall(dm_table_entry_t *table_en, struct buf *bp)
{
return 0;
}