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[netbsd-mini2440.git] / sys / dev / dm / device-mapper.c

/*        $NetBSD: device-mapper.c,v 1.14 2010/01/03 22:55:25 haad Exp $ */

/*
 * Copyright (c) 2008 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.
 */

/*
 * I want to say thank you to all people who helped me with this project.
 */

#include <sys/types.h>
#include <sys/param.h>

#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/dkio.h>
#include <sys/disk.h>
#include <sys/disklabel.h>
#include <sys/ioctl.h>
#include <sys/ioccom.h>
#include <sys/kmem.h>
#include <sys/module.h>

#include "netbsd-dm.h"
#include "dm.h"

static dev_type_open(dmopen);
static dev_type_close(dmclose);
static dev_type_read(dmread);
static dev_type_write(dmwrite);
static dev_type_ioctl(dmioctl);
static dev_type_strategy(dmstrategy);
static dev_type_size(dmsize);

/* attach and detach routines */
int dmattach(void);
int dmdestroy(void);

static int dm_cmd_to_fun(prop_dictionary_t);
static int disk_ioctl_switch(dev_t, u_long, void *);
static int dm_ioctl_switch(u_long);
static void dmminphys(struct buf *);

/* CF attach/detach functions used for power management */
static int dm_detach(device_t, int);
static void dm_attach(device_t, device_t, void *);
static int dm_match(device_t, cfdata_t, void *);

/* ***Variable-definitions*** */
const struct bdevsw dm_bdevsw = {
        .d_open = dmopen,
        .d_close = dmclose,
        .d_strategy = dmstrategy,
        .d_ioctl = dmioctl,
        .d_dump = nodump,
        .d_psize = dmsize,
        .d_flag = D_DISK | D_MPSAFE
};

const struct cdevsw dm_cdevsw = {
        .d_open = dmopen,
        .d_close = dmclose,
        .d_read = dmread,
        .d_write = dmwrite,
        .d_ioctl = dmioctl,
        .d_stop = nostop,
        .d_tty = notty,
        .d_poll = nopoll,
        .d_mmap = nommap,
        .d_kqfilter = nokqfilter,
        .d_flag = D_DISK | D_MPSAFE
};

const struct dkdriver dmdkdriver = {
        .d_strategy = dmstrategy
};

#ifdef _MODULE
/* Autoconf defines */
CFDRIVER_DECL(dm, DV_DISK, NULL);
#endif

CFATTACH_DECL3_NEW(dm, 0,
     dm_match, dm_attach, dm_detach, NULL, NULL, NULL,
     DVF_DETACH_SHUTDOWN);

extern struct cfdriver dm_cd;

extern uint64_t dev_counter;

/*
 * This array is used to translate cmd to function pointer.
 *
 * Interface between libdevmapper and lvm2tools uses different 
 * names for one IOCTL call because libdevmapper do another thing
 * then. When I run "info" or "mknodes" libdevmapper will send same
 * ioctl to kernel but will do another things in userspace.
 *
 */
struct cmd_function cmd_fn[] = {
                { .cmd = "version", .fn = dm_get_version_ioctl},
                { .cmd = "targets", .fn = dm_list_versions_ioctl},
                { .cmd = "create",  .fn = dm_dev_create_ioctl},
                { .cmd = "info",    .fn = dm_dev_status_ioctl},
                { .cmd = "mknodes", .fn = dm_dev_status_ioctl},         
                { .cmd = "names",   .fn = dm_dev_list_ioctl},
                { .cmd = "suspend", .fn = dm_dev_suspend_ioctl},
                { .cmd = "remove",  .fn = dm_dev_remove_ioctl}, 
                { .cmd = "rename",  .fn = dm_dev_rename_ioctl},
                { .cmd = "resume",  .fn = dm_dev_resume_ioctl},
                { .cmd = "clear",   .fn = dm_table_clear_ioctl},
                { .cmd = "deps",    .fn = dm_table_deps_ioctl},
                { .cmd = "reload",  .fn = dm_table_load_ioctl},
                { .cmd = "status",  .fn = dm_table_status_ioctl},
                { .cmd = "table",   .fn = dm_table_status_ioctl},
                {NULL, NULL}    
};

MODULE(MODULE_CLASS_DRIVER, dm, NULL);

/* New module handle routine */
static int
dm_modcmd(modcmd_t cmd, void *arg)
{
#ifdef _MODULE
        int bmajor = -1, cmajor = -1;
        int error;

        error = 0;

        switch (cmd) {
        case MODULE_CMD_INIT:
                dmattach();

                error = config_cfdriver_attach(&dm_cd);
                if (error)
                        break;

                error = config_cfattach_attach(dm_cd.cd_name, &dm_ca);
                if (error) {
                        config_cfdriver_detach(&dm_cd);
                        aprint_error("Unable to register cfattach for dm driver\n");

                        break;
                }

                error =  devsw_attach("dm", &dm_bdevsw, &bmajor,
                    &dm_cdevsw, &cmajor);
                break;

        case MODULE_CMD_FINI:
                /*
                 * Disable unloading of dm module if there are any devices
                 * defined in driver. This is probably too strong we need
                 * to disable auto-unload only if there is mounted dm device
                 * present.
                 */ 
                if (dev_counter > 0)
                        return EBUSY;
                dmdestroy();

                error = config_cfattach_detach(dm_cd.cd_name, &dm_ca);
                if (error)
                        break;

                config_cfdriver_detach(&dm_cd);

                devsw_detach(&dm_bdevsw, &dm_cdevsw);
                break;
        case MODULE_CMD_STAT:
                return ENOTTY;

        default:
                return ENOTTY;
        }

        return error;
#else

        if (cmd == MODULE_CMD_INIT)
                return 0;
        return ENOTTY;

#endif /* _MODULE */
}


/*
 * dm_match:
 *
 *      Autoconfiguration match function for pseudo-device glue.
 */
static int
dm_match(device_t parent, cfdata_t match,
    void *aux)
{

        /* Pseudo-device; always present. */
        return (1);
}

/*
 * dm_attach:
 *
 *      Autoconfiguration attach function for pseudo-device glue.
 */
static void
dm_attach(device_t parent, device_t self,
    void *aux)
{
        return;
}


/*
 * dm_detach:
 *
 *      Autoconfiguration detach function for pseudo-device glue.
 * This routine is called by dm_ioctl::dm_dev_remove_ioctl and by autoconf to
 * remove devices created in device-mapper. 
 */
static int
dm_detach(device_t self, int flags)
{
        dm_dev_t *dmv;

        /* Detach device from global device list */
        if ((dmv = dm_dev_detach(self)) == NULL)
                return ENOENT;

        /* Destroy active table first.  */
        dm_table_destroy(&dmv->table_head, DM_TABLE_ACTIVE);

        /* Destroy inactive table if exits, too. */
        dm_table_destroy(&dmv->table_head, DM_TABLE_INACTIVE);
        
        dm_table_head_destroy(&dmv->table_head);

        /* Destroy disk device structure */
        disk_detach(dmv->diskp);
        disk_destroy(dmv->diskp);

        /* Destroy device */
        (void)dm_dev_free(dmv);

        /* Decrement device counter After removing device */
        atomic_dec_64(&dev_counter);

        return 0;
}

/* attach routine */
int
dmattach(void)
{

        dm_target_init();
        dm_dev_init();
        dm_pdev_init();

        return 0;
}

/* Destroy routine */
int
dmdestroy(void)
{

        dm_dev_destroy();
        dm_pdev_destroy();
        dm_target_destroy();

        return 0;
}

static int
dmopen(dev_t dev, int flags, int mode, struct lwp *l)
{

        aprint_debug("dm open routine called %" PRIu32 "\n", minor(dev));
        return 0;
}

static int
dmclose(dev_t dev, int flags, int mode, struct lwp *l)
{

        aprint_debug("dm close routine called %" PRIu32 "\n", minor(dev));
        return 0;
}


static int
dmioctl(dev_t dev, const u_long cmd, void *data, int flag, struct lwp *l)
{
        int r;
        prop_dictionary_t dm_dict_in;

        r = 0;

        aprint_debug("dmioctl called\n");
        
        KASSERT(data != NULL);
        
        if (( r = disk_ioctl_switch(dev, cmd, data)) == ENOTTY) {
                struct plistref *pref = (struct plistref *) data;

                /* Check if we were called with NETBSD_DM_IOCTL ioctl
                   otherwise quit. */
                if ((r = dm_ioctl_switch(cmd)) != 0)
                        return r;

                if((r = prop_dictionary_copyin_ioctl(pref, cmd, &dm_dict_in)) != 0)
                        return r;

                if ((r = dm_check_version(dm_dict_in)) != 0)
                        goto cleanup_exit;

                /* run ioctl routine */
                if ((r = dm_cmd_to_fun(dm_dict_in)) != 0)
                        goto cleanup_exit;

cleanup_exit:
                r = prop_dictionary_copyout_ioctl(pref, cmd, dm_dict_in);
                prop_object_release(dm_dict_in);
        }

        return r;
}

/*
 * Translate command sent from libdevmapper to func.
 */
static int
dm_cmd_to_fun(prop_dictionary_t dm_dict){
        int i, r;
        prop_string_t command;
        
        r = 0;

        if ((command = prop_dictionary_get(dm_dict, DM_IOCTL_COMMAND)) == NULL)
                return EINVAL;

        for(i = 0; cmd_fn[i].cmd != NULL; i++)
                if (prop_string_equals_cstring(command, cmd_fn[i].cmd))
                        break;

        if (cmd_fn[i].cmd == NULL)
                return EINVAL;

        aprint_debug("ioctl %s called\n", cmd_fn[i].cmd);
        r = cmd_fn[i].fn(dm_dict);

        return r;
}

/* Call apropriate ioctl handler function. */
static int
dm_ioctl_switch(u_long cmd)
{

        switch(cmd) {

        case NETBSD_DM_IOCTL:
                aprint_debug("dm NetBSD_DM_IOCTL called\n");
                break;
        default:
                 aprint_debug("dm unknown ioctl called\n");
                 return ENOTTY;
                 break; /* NOT REACHED */
        }

         return 0;
}

 /*
  * Check for disk specific ioctls.
  */

static int
disk_ioctl_switch(dev_t dev, u_long cmd, void *data)
{
        dm_dev_t *dmv;

        switch(cmd) {
        case DIOCGWEDGEINFO:
        {
                struct dkwedge_info *dkw = (void *) data;

                if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
                        return ENODEV;

                aprint_debug("DIOCGWEDGEINFO ioctl called\n");

                strlcpy(dkw->dkw_devname, dmv->name, 16);
                strlcpy(dkw->dkw_wname, dmv->name, DM_NAME_LEN);
                strlcpy(dkw->dkw_parent, dmv->name, 16);

                dkw->dkw_offset = 0;
                dkw->dkw_size = dm_table_size(&dmv->table_head);
                strcpy(dkw->dkw_ptype, DKW_PTYPE_FFS);

                dm_dev_unbusy(dmv);
                break;
        }

        case DIOCGDISKINFO:
        {
                struct plistref *pref = (struct plistref *) data;

                if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
                        return ENODEV;

                if (dmv->diskp->dk_info == NULL) {
                        dm_dev_unbusy(dmv);
                        return ENOTSUP;
                } else
                        prop_dictionary_copyout_ioctl(pref, cmd,
                            dmv->diskp->dk_info);

                dm_dev_unbusy(dmv);
                break;
        }
        
        default:
                aprint_debug("unknown disk_ioctl called\n");
                return ENOTTY;
                break; /* NOT REACHED */
        }

        return 0;
}

/*
 * Do all IO operations on dm logical devices.
 */
static void
dmstrategy(struct buf *bp)
{
        dm_dev_t *dmv;
        dm_table_t  *tbl;
        dm_table_entry_t *table_en;
        struct buf *nestbuf;

        uint32_t dev_type;

        uint64_t buf_start, buf_len, issued_len;
        uint64_t table_start, table_end;
        uint64_t start, end;

        buf_start = bp->b_blkno * DEV_BSIZE;
        buf_len = bp->b_bcount;

        tbl = NULL; 

        table_end = 0;
        dev_type = 0;
        issued_len = 0;

        if ((dmv = dm_dev_lookup(NULL, NULL, minor(bp->b_dev))) == NULL) {
                bp->b_error = EIO;
                bp->b_resid = bp->b_bcount;
                biodone(bp);
                return;
        } 

        if (bounds_check_with_mediasize(bp, DEV_BSIZE,
            dm_table_size(&dmv->table_head)) <= 0) {
                dm_dev_unbusy(dmv);
                bp->b_resid = bp->b_bcount;
                biodone(bp);
                return;
        }

        /*
         * disk(9) is part of device structure and it can't be used without
         * mutual exclusion, use diskp_mtx until it will be fixed.
         */
        mutex_enter(&dmv->diskp_mtx);
        disk_busy(dmv->diskp);
        mutex_exit(&dmv->diskp_mtx);

        /* Select active table */
        tbl = dm_table_get_entry(&dmv->table_head, DM_TABLE_ACTIVE);

         /* Nested buffers count down to zero therefore I have
            to set bp->b_resid to maximal value. */
        bp->b_resid = bp->b_bcount;

        /*
         * Find out what tables I want to select.
         */
        SLIST_FOREACH(table_en, tbl, next)
        {
                /* I need need number of bytes not blocks. */
                table_start = table_en->start * DEV_BSIZE;
                /*
                 * I have to sub 1 from table_en->length to prevent
                 * off by one error
                 */
                table_end = table_start + (table_en->length)* DEV_BSIZE;

                start = MAX(table_start, buf_start);

                end = MIN(table_end, buf_start + buf_len);

                aprint_debug("----------------------------------------\n");
                aprint_debug("table_start %010" PRIu64", table_end %010"
                    PRIu64 "\n", table_start, table_end);
                aprint_debug("buf_start %010" PRIu64", buf_len %010"
                    PRIu64"\n", buf_start, buf_len);
                aprint_debug("start-buf_start %010"PRIu64", end %010"
                    PRIu64"\n", start - buf_start, end);
                aprint_debug("start %010" PRIu64" , end %010"
                    PRIu64"\n", start, end);
                aprint_debug("\n----------------------------------------\n");

                if (start < end) {
                        /* create nested buffer  */
                        nestbuf = getiobuf(NULL, true);

                        nestiobuf_setup(bp, nestbuf, start - buf_start,
                            (end - start));

                        issued_len += end - start;

                        /* I need number of blocks. */
                        nestbuf->b_blkno = (start - table_start) / DEV_BSIZE;

                        table_en->target->strategy(table_en, nestbuf);
                }
        }

        if (issued_len < buf_len)
                nestiobuf_done(bp, buf_len - issued_len, EINVAL);

        mutex_enter(&dmv->diskp_mtx);
        disk_unbusy(dmv->diskp, buf_len, bp != NULL ? bp->b_flags & B_READ : 0);
        mutex_exit(&dmv->diskp_mtx);

        dm_table_release(&dmv->table_head, DM_TABLE_ACTIVE);
        dm_dev_unbusy(dmv);

        return;
}


static int
dmread(dev_t dev, struct uio *uio, int flag)
{

        return (physio(dmstrategy, NULL, dev, B_READ, dmminphys, uio));
}

static int
dmwrite(dev_t dev, struct uio *uio, int flag)
{

        return (physio(dmstrategy, NULL, dev, B_WRITE, dmminphys, uio));
}

static int
dmsize(dev_t dev)
{
        dm_dev_t *dmv;
        uint64_t size;

        size = 0;

        if ((dmv = dm_dev_lookup(NULL, NULL, minor(dev))) == NULL)
                        return -ENOENT;

        size = dm_table_size(&dmv->table_head);
        dm_dev_unbusy(dmv);
        
        return size;
}

static void
dmminphys(struct buf *bp)
{

        bp->b_bcount = MIN(bp->b_bcount, MAXPHYS);
}

void
dmgetproperties(struct disk *disk, dm_table_head_t *head)
{
        prop_dictionary_t disk_info, odisk_info, geom;
        int dmp_size;

        dmp_size = dm_table_size(head);
        disk_info = prop_dictionary_create();
        geom = prop_dictionary_create();

        prop_dictionary_set_cstring_nocopy(disk_info, "type", "ESDI");
        prop_dictionary_set_uint64(geom, "sectors-per-unit", dmp_size);
        prop_dictionary_set_uint32(geom, "sector-size",
            DEV_BSIZE /* XXX 512? */);
        prop_dictionary_set_uint32(geom, "sectors-per-track", 32);
        prop_dictionary_set_uint32(geom, "tracks-per-cylinder", 64);
        prop_dictionary_set_uint32(geom, "cylinders-per-unit", dmp_size / 2048);
        prop_dictionary_set(disk_info, "geometry", geom);
        prop_object_release(geom);

        odisk_info = disk->dk_info;
        disk->dk_info = disk_info;

        if (odisk_info != NULL)
                prop_object_release(odisk_info);
}