/*-
 * Copyright (c) 2006, 2007 Marcel Moolenaar
 * All rights reserved.
 *
 * 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 AUTHOR ``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 AUTHOR 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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/apm.h>
#include <sys/bio.h>
#include <sys/diskmbr.h>
#include <sys/endian.h>
#include <sys/kernel.h>
#include <sys/kobj.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/systm.h>
#include <geom/geom.h>
#include <geom/part/g_part.h>

#include "g_part_if.h"

struct g_part_apm_table {
	struct g_part_table	base;
	struct apm_ddr		ddr;
	struct apm_ent		self;
};

struct g_part_apm_entry {
	struct g_part_entry	base;
	struct apm_ent		ent;
};

static int g_part_apm_add(struct g_part_table *, struct g_part_entry *,
    struct g_part_parms *);
static int g_part_apm_create(struct g_part_table *, struct g_part_parms *);
static int g_part_apm_destroy(struct g_part_table *, struct g_part_parms *);
static int g_part_apm_dumpto(struct g_part_table *, struct g_part_entry *);
static int g_part_apm_modify(struct g_part_table *, struct g_part_entry *,
    struct g_part_parms *);
static char *g_part_apm_name(struct g_part_table *, struct g_part_entry *,
    char *, size_t);
static int g_part_apm_probe(struct g_part_table *, struct g_consumer *);
static int g_part_apm_read(struct g_part_table *, struct g_consumer *);
static const char *g_part_apm_type(struct g_part_table *, struct g_part_entry *,
    char *, size_t);
static int g_part_apm_write(struct g_part_table *, struct g_consumer *);

static kobj_method_t g_part_apm_methods[] = {
	KOBJMETHOD(g_part_add,		g_part_apm_add),
	KOBJMETHOD(g_part_create,	g_part_apm_create),
	KOBJMETHOD(g_part_destroy,	g_part_apm_destroy),
	KOBJMETHOD(g_part_dumpto,	g_part_apm_dumpto),
	KOBJMETHOD(g_part_modify,	g_part_apm_modify),
	KOBJMETHOD(g_part_name,		g_part_apm_name),
	KOBJMETHOD(g_part_probe,	g_part_apm_probe),
	KOBJMETHOD(g_part_read,		g_part_apm_read),
	KOBJMETHOD(g_part_type,		g_part_apm_type),
	KOBJMETHOD(g_part_write,	g_part_apm_write),
	{ 0, 0 }
};

static struct g_part_scheme g_part_apm_scheme = {
	"APM",
	g_part_apm_methods,
	sizeof(struct g_part_apm_table),
	.gps_entrysz = sizeof(struct g_part_apm_entry),
	.gps_minent = 16,
	.gps_maxent = INT_MAX,
};
G_PART_SCHEME_DECLARE(g_part_apm_scheme);

static int
apm_parse_type(const char *type, char *buf, size_t bufsz)
{
	const char *alias;

	if (type[0] == '!') {
		type++;
		if (strlen(type) > bufsz)
			return (EINVAL);
		if (!strcmp(type, APM_ENT_TYPE_SELF) ||
		    !strcmp(type, APM_ENT_TYPE_UNUSED))
			return (EINVAL);
		strncpy(buf, type, bufsz);
		return (0);
	}
	alias = g_part_alias_name(G_PART_ALIAS_FREEBSD);
	if (!strcasecmp(type, alias)) {
		strcpy(buf, APM_ENT_TYPE_FREEBSD);
		return (0);
	}
	alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_SWAP);
	if (!strcasecmp(type, alias)) {
		strcpy(buf, APM_ENT_TYPE_FREEBSD_SWAP);
		return (0);
	}
	alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_UFS);
	if (!strcasecmp(type, alias)) {
		strcpy(buf, APM_ENT_TYPE_FREEBSD_UFS);
		return (0);
	}
	alias = g_part_alias_name(G_PART_ALIAS_FREEBSD_VINUM);
	if (!strcasecmp(type, alias)) {
		strcpy(buf, APM_ENT_TYPE_FREEBSD_VINUM);
		return (0);
	}
	return (EINVAL);
}

static int
apm_read_ent(struct g_consumer *cp, uint32_t blk, struct apm_ent *ent)
{
	struct g_provider *pp;
	char *buf;
	int error;

	pp = cp->provider;
	buf = g_read_data(cp, pp->sectorsize * blk, pp->sectorsize, &error);
	if (buf == NULL)
		return (error);
	ent->ent_sig = be16dec(buf);
	ent->ent_pmblkcnt = be32dec(buf + 4);
	ent->ent_start = be32dec(buf + 8);
	ent->ent_size = be32dec(buf + 12);
	bcopy(buf + 16, ent->ent_name, sizeof(ent->ent_name));
	bcopy(buf + 48, ent->ent_type, sizeof(ent->ent_type));
	g_free(buf);
	return (0);
}

static int
g_part_apm_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 
    struct g_part_parms *gpp)
{
	struct g_part_apm_entry *entry;
	struct g_part_apm_table *table;
	int error;

	entry = (struct g_part_apm_entry *)baseentry;
	table = (struct g_part_apm_table *)basetable;
	entry->ent.ent_sig = APM_ENT_SIG;
	entry->ent.ent_pmblkcnt = table->self.ent_pmblkcnt;
	entry->ent.ent_start = gpp->gpp_start;
	entry->ent.ent_size = gpp->gpp_size;
	if (baseentry->gpe_deleted) {
		bzero(entry->ent.ent_type, sizeof(entry->ent.ent_type));
		bzero(entry->ent.ent_name, sizeof(entry->ent.ent_name));
	}
	error = apm_parse_type(gpp->gpp_type, entry->ent.ent_type,
	    sizeof(entry->ent.ent_type));
	if (error)
		return (error);
	if (gpp->gpp_parms & G_PART_PARM_LABEL) {
		if (strlen(gpp->gpp_label) > sizeof(entry->ent.ent_name))
			return (EINVAL);
		strncpy(entry->ent.ent_name, gpp->gpp_label,
		    sizeof(entry->ent.ent_name));
	}
	return (0);
}

static int
g_part_apm_create(struct g_part_table *basetable, struct g_part_parms *gpp)
{
	struct g_provider *pp;
	struct g_part_apm_table *table;

	table = (struct g_part_apm_table *)basetable;
	pp = gpp->gpp_provider;
	if (pp->sectorsize != 512 ||
	    pp->mediasize < (2 + 2 * basetable->gpt_entries) * pp->sectorsize)
		return (ENOSPC);

	basetable->gpt_first = 2 + basetable->gpt_entries;
	basetable->gpt_last = (pp->mediasize / pp->sectorsize) - 1;

	table->ddr.ddr_sig = APM_DDR_SIG;
	table->ddr.ddr_blksize = pp->sectorsize;
	table->ddr.ddr_blkcount = basetable->gpt_last + 1;

	table->self.ent_sig = APM_ENT_SIG;
	table->self.ent_pmblkcnt = basetable->gpt_entries + 1;
	table->self.ent_start = 1;
	table->self.ent_size = table->self.ent_pmblkcnt;
	strcpy(table->self.ent_name, "Apple");
	strcpy(table->self.ent_type, APM_ENT_TYPE_SELF);
	return (0);
}

static int
g_part_apm_destroy(struct g_part_table *basetable, struct g_part_parms *gpp)
{

	/* Wipe the first 2 sectors to clear the partitioning. */
	basetable->gpt_smhead |= 3;
	return (0);
}

static int
g_part_apm_dumpto(struct g_part_table *table, struct g_part_entry *baseentry)
{
	struct g_part_apm_entry *entry;

	entry = (struct g_part_apm_entry *)baseentry;
	return ((!strcmp(entry->ent.ent_type, APM_ENT_TYPE_FREEBSD_SWAP))
	    ? 1 : 0);
}

static int
g_part_apm_modify(struct g_part_table *basetable,
    struct g_part_entry *baseentry, struct g_part_parms *gpp)
{
	struct g_part_apm_entry *entry;
	int error;

	entry = (struct g_part_apm_entry *)baseentry;
	if (gpp->gpp_parms & G_PART_PARM_LABEL) {
		if (strlen(gpp->gpp_label) > sizeof(entry->ent.ent_name))
			return (EINVAL);
	}
	if (gpp->gpp_parms & G_PART_PARM_TYPE) {
		error = apm_parse_type(gpp->gpp_type, entry->ent.ent_type,
		    sizeof(entry->ent.ent_type));
		if (error)
			return (error);
	}
	if (gpp->gpp_parms & G_PART_PARM_LABEL) {
		strncpy(entry->ent.ent_name, gpp->gpp_label,
		    sizeof(entry->ent.ent_name));
	}
	return (0);
}

static char *
g_part_apm_name(struct g_part_table *table, struct g_part_entry *baseentry,
    char *buf, size_t bufsz)
{

	snprintf(buf, bufsz, "s%d", baseentry->gpe_index + 1);
	return (buf);
}

static int
g_part_apm_probe(struct g_part_table *basetable, struct g_consumer *cp)
{
	struct g_provider *pp;
	struct g_part_apm_table *table;
	char *buf;
	int error;

	/* We don't nest, which means that our depth should be 0. */
	if (basetable->gpt_depth != 0)
		return (ENXIO);

	table = (struct g_part_apm_table *)basetable;
	pp = cp->provider;

	/* Sanity-check the provider. */
	if (pp->mediasize < 4 * pp->sectorsize)
		return (ENOSPC);

	/* Check that there's a Driver Descriptor Record (DDR). */
	buf = g_read_data(cp, 0L, pp->sectorsize, &error);
	if (buf == NULL)
		return (error);
	table->ddr.ddr_sig = be16dec(buf);
	table->ddr.ddr_blksize = be16dec(buf + 2);
	table->ddr.ddr_blkcount = be32dec(buf + 4);
	g_free(buf);
	if (table->ddr.ddr_sig != APM_DDR_SIG)
		return (ENXIO);
	if (table->ddr.ddr_blksize != pp->sectorsize)
		return (ENXIO);

	/* Check that there's a Partition Map. */
	error = apm_read_ent(cp, 1, &table->self);
	if (error)
		return (error);
	if (table->self.ent_sig != APM_ENT_SIG)
		return (ENXIO);
	if (strcmp(table->self.ent_type, APM_ENT_TYPE_SELF))
		return (ENXIO);
	if (table->self.ent_pmblkcnt >= table->ddr.ddr_blkcount)
		return (ENXIO);
	return (G_PART_PROBE_PRI_NORM);
}

static int
g_part_apm_read(struct g_part_table *basetable, struct g_consumer *cp)
{
	struct apm_ent ent;
	struct g_part_apm_entry *entry;
	struct g_part_apm_table *table;
	int error, index;

	table = (struct g_part_apm_table *)basetable;

	basetable->gpt_first = table->self.ent_pmblkcnt + 1;
	basetable->gpt_last = table->ddr.ddr_blkcount - 1;
	basetable->gpt_entries = table->self.ent_pmblkcnt - 1;

	for (index = table->self.ent_pmblkcnt - 1; index > 0; index--) {
		error = apm_read_ent(cp, index + 1, &ent);
		if (error)
			continue;
		if (!strcmp(ent.ent_type, APM_ENT_TYPE_UNUSED))
			continue;
		entry = (struct g_part_apm_entry *)g_part_new_entry(basetable,
		    index, ent.ent_start, ent.ent_start + ent.ent_size - 1);
		entry->ent = ent;
	}

	return (0);
}

static const char *
g_part_apm_type(struct g_part_table *basetable, struct g_part_entry *baseentry,
    char *buf, size_t bufsz)
{
	struct g_part_apm_entry *entry;
	const char *type;
	size_t len;

	entry = (struct g_part_apm_entry *)baseentry;
	type = entry->ent.ent_type;
	if (!strcmp(type, APM_ENT_TYPE_FREEBSD))
		return (g_part_alias_name(G_PART_ALIAS_FREEBSD));
	if (!strcmp(type, APM_ENT_TYPE_FREEBSD_SWAP))
		return (g_part_alias_name(G_PART_ALIAS_FREEBSD_SWAP));
	if (!strcmp(type, APM_ENT_TYPE_FREEBSD_UFS))
		return (g_part_alias_name(G_PART_ALIAS_FREEBSD_UFS));
	if (!strcmp(type, APM_ENT_TYPE_FREEBSD_VINUM))
		return (g_part_alias_name(G_PART_ALIAS_FREEBSD_VINUM));
	buf[0] = '!';
	len = MIN(sizeof(entry->ent.ent_type), bufsz - 2);
	bcopy(type, buf + 1, len);
	buf[len + 1] = '\0';
	return (buf);
}

static int
g_part_apm_write(struct g_part_table *basetable, struct g_consumer *cp)
{
	char buf[512];
	struct g_part_entry *baseentry;
	struct g_part_apm_entry *entry;
	struct g_part_apm_table *table;
	int error, index;

	table = (struct g_part_apm_table *)basetable;
	bzero(buf, sizeof(buf));

	/* Write the DDR and 'self' entry only when we're newly created. */
	if (basetable->gpt_created) {
		be16enc(buf, table->ddr.ddr_sig);
		be16enc(buf + 2, table->ddr.ddr_blksize);
		be32enc(buf + 4, table->ddr.ddr_blkcount);
		error = g_write_data(cp, 0, buf, sizeof(buf));
		if (error)
			return (error);
	}

	be16enc(buf, table->self.ent_sig);
	be16enc(buf + 2, 0);
	be32enc(buf + 4, table->self.ent_pmblkcnt);

	if (basetable->gpt_created) {
		be32enc(buf + 8, table->self.ent_start);
		be32enc(buf + 12, table->self.ent_size);
		bcopy(table->self.ent_name, buf + 16,
		    sizeof(table->self.ent_name));
		bcopy(table->self.ent_type, buf + 48,
		    sizeof(table->self.ent_type));
		error = g_write_data(cp, 512, buf, sizeof(buf));
		if (error)
			return (error);
	}

	baseentry = LIST_FIRST(&basetable->gpt_entry);
	for (index = 1; index <= basetable->gpt_entries; index++) {
		entry = (baseentry != NULL && index == baseentry->gpe_index)
		    ? (struct g_part_apm_entry *)baseentry : NULL;
		if (entry != NULL && !baseentry->gpe_deleted) {
			be32enc(buf + 8, entry->ent.ent_start);
			be32enc(buf + 12, entry->ent.ent_size);
			bcopy(entry->ent.ent_name, buf + 16,
			    sizeof(entry->ent.ent_name));
			bcopy(entry->ent.ent_type, buf + 48,
			    sizeof(entry->ent.ent_type));
		} else {
			bzero(buf + 8, 4 + 4 + 32 + 32);
			strcpy(buf + 48, APM_ENT_TYPE_UNUSED);
		}
		error = g_write_data(cp, (index + 1) * 512, buf, sizeof(buf));
		if (error)
			return (error);
		if (entry != NULL)
			baseentry = LIST_NEXT(baseentry, gpe_entry);
	}

	return (0);
}