/*
 * Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
 * Copyright (C) 2004 Red Hat, Inc. All rights reserved.
 *
 * This file is part of LVM2.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License v.2.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "tools.h"

struct lvresize_params {
	const char *vg_name;
	const char *lv_name;

	uint32_t stripes;
	uint32_t stripe_size;

	struct segment_type *segtype;

	/* size */
	uint32_t extents;
	uint64_t size;
	sign_t sign;

	enum {
		LV_ANY = 0,
		LV_REDUCE = 1,
		LV_EXTEND = 2
	} resize;

	int argc;
	char **argv;
};

static int _read_params(struct cmd_context *cmd, int argc, char **argv,
			struct lvresize_params *lp)
{
	const char *cmd_name;
	char *st;

	lp->sign = SIGN_NONE;
	lp->resize = LV_ANY;

	cmd_name = command_name(cmd);
	if (!strcmp(cmd_name, "lvreduce"))
		lp->resize = LV_REDUCE;
	if (!strcmp(cmd_name, "lvextend"))
		lp->resize = LV_EXTEND;

	if (arg_count(cmd, extents_ARG) + arg_count(cmd, size_ARG) != 1) {
		log_error("Please specify either size or extents (not both)");
		return 0;
	}

	if (arg_count(cmd, extents_ARG)) {
		lp->extents = arg_uint_value(cmd, extents_ARG, 0);
		lp->sign = arg_sign_value(cmd, extents_ARG, SIGN_NONE);
	}

	/* Size returned in kilobyte units; held in sectors */
	if (arg_count(cmd, size_ARG)) {
		lp->size = arg_uint64_value(cmd, size_ARG, UINT64_C(0)) * 2;
		lp->sign = arg_sign_value(cmd, size_ARG, SIGN_NONE);
	}

	if (lp->resize == LV_EXTEND && lp->sign == SIGN_MINUS) {
		log_error("Negative argument not permitted - use lvreduce");
		return 0;
	}

	if (lp->resize == LV_REDUCE && lp->sign == SIGN_PLUS) {
		log_error("Positive sign not permitted - use lvextend");
		return 0;
	}

	if (!argc) {
		log_error("Please provide the logical volume name");
		return 0;
	}

	lp->lv_name = argv[0];
	argv++;
	argc--;

	if (!(lp->vg_name = extract_vgname(cmd, lp->lv_name))) {
		log_error("Please provide a volume group name");
		return 0;
	}

	if ((st = strrchr(lp->lv_name, '/')))
		lp->lv_name = st + 1;

	lp->argc = argc;
	lp->argv = argv;

	return 1;
}

static int _lvresize(struct cmd_context *cmd, struct lvresize_params *lp)
{
	struct volume_group *vg;
	struct logical_volume *lv;
	struct snapshot *snap;
	struct lvinfo info;
	uint32_t stripesize_extents = 0;
	uint32_t seg_stripes = 0, seg_stripesize = 0, seg_size = 0;
	uint32_t extents_used = 0;
	uint32_t size_rest;
	alloc_policy_t alloc;
	char *lock_lvid;
	struct lv_list *lvl;
	int consistent = 1;
	struct lv_segment *seg;
	uint32_t seg_extents;
	uint32_t sz, str;
	struct list *pvh = NULL;

	if (!(vg = vg_read(cmd, lp->vg_name, &consistent))) {
		log_error("Volume group %s doesn't exist", lp->vg_name);
		return ECMD_FAILED;
	}

	if (vg->status & EXPORTED_VG) {
		log_error("Volume group %s is exported", vg->name);
		return ECMD_FAILED;
	}

	if (!(vg->status & LVM_WRITE)) {
		log_error("Volume group %s is read-only", lp->vg_name);
		return ECMD_FAILED;
	}

	/* does LV exist? */
	if (!(lvl = find_lv_in_vg(vg, lp->lv_name))) {
		log_error("Logical volume %s not found in volume group %s",
			  lp->lv_name, lp->vg_name);
		return ECMD_FAILED;
	}

	if (arg_count(cmd, stripes_ARG)) {
		if (vg->fid->fmt->features & FMT_SEGMENTS)
			lp->stripes = arg_uint_value(cmd, stripes_ARG, 1);
		else
			log_print("Varied striping not supported. Ignoring.");
	}

	if (arg_count(cmd, stripesize_ARG)) {
		if (arg_sign_value(cmd, stripesize_ARG, 0) == SIGN_MINUS) {
			log_error("Stripesize may not be negative.");
			return ECMD_FAILED;
		}
		if (vg->fid->fmt->features & FMT_SEGMENTS)
			lp->stripe_size = 2 * arg_uint_value(cmd,
							     stripesize_ARG, 0);
		else
			log_print("Varied stripesize not supported. Ignoring.");
	}

	lv = lvl->lv;

	if (lv->status & LOCKED) {
		log_error("Can't resize locked LV %s", lv->name);
		return ECMD_FAILED;
	}

	alloc = (alloc_policy_t) arg_uint_value(cmd, alloc_ARG, lv->alloc);

	if (lp->size) {
		if (lp->size % vg->extent_size) {
			if (lp->sign == SIGN_MINUS)
				lp->size -= lp->size % vg->extent_size;
			else
				lp->size += vg->extent_size -
				    (lp->size % vg->extent_size);

			log_print("Rounding up size to full physical extent %s",
				  display_size(cmd, (uint64_t) lp->size / 2,
					       SIZE_SHORT));
		}

		lp->extents = lp->size / vg->extent_size;
	}

	if (lp->sign == SIGN_PLUS)
		lp->extents += lv->le_count;

	if (lp->sign == SIGN_MINUS) {
		if (lp->extents >= lv->le_count) {
			log_error("Unable to reduce %s below 1 extent",
				  lp->lv_name);
			return EINVALID_CMD_LINE;
		}

		lp->extents = lv->le_count - lp->extents;
	}

	if (!lp->extents) {
		log_error("New size of 0 not permitted");
		return EINVALID_CMD_LINE;
	}

	if (lp->extents == lv->le_count) {
		log_error("New size (%d extents) matches existing size "
			  "(%d extents)", lp->extents, lv->le_count);
		return EINVALID_CMD_LINE;
	}

	seg_size = lp->extents - lv->le_count;

	/* Use segment type of last segment */
	list_iterate_items(seg, &lv->segments) {
		lp->segtype = seg->segtype;
	}

	/* FIXME Support LVs with mixed segment types */
	if (lp->segtype != (struct segment_type *) arg_ptr_value(cmd, type_ARG,
								 lp->segtype)) {
		log_error("VolumeType does not match (%s)", lp->segtype->name);
		return EINVALID_CMD_LINE;
	}

	/* If extending, find stripes, stripesize & size of last segment */
	if ((lp->extents > lv->le_count) &&
	    !(lp->stripes == 1 || (lp->stripes > 1 && lp->stripe_size))) {
		list_iterate_items(seg, &lv->segments) {
			if (!(seg->segtype->flags & SEG_AREAS_STRIPED))
				continue;

			sz = seg->stripe_size;
			str = seg->area_count;

			if ((seg_stripesize && seg_stripesize != sz
			     && !lp->stripe_size) ||
			    (seg_stripes && seg_stripes != str && !lp->stripes)) {
				log_error("Please specify number of "
					  "stripes (-i) and stripesize (-I)");
				return EINVALID_CMD_LINE;
			}

			seg_stripesize = sz;
			seg_stripes = str;
		}

		if (!lp->stripes)
			lp->stripes = seg_stripes;

		if (!lp->stripe_size && lp->stripes > 1) {
			if (seg_stripesize) {
				log_print("Using stripesize of last segment "
					  "%dKB", seg_stripesize / 2);
				lp->stripe_size = seg_stripesize;
			} else {
				lp->stripe_size =
					find_config_int(cmd->cft->root,
							"metadata/stripesize",
							DEFAULT_STRIPESIZE) * 2;
				log_print("Using default stripesize %dKB",
					  lp->stripe_size / 2);
			}
		}
	}

	/* If reducing, find stripes, stripesize & size of last segment */
	if (lp->extents < lv->le_count) {
		extents_used = 0;

		if (lp->stripes || lp->stripe_size)
			log_error("Ignoring stripes and stripesize arguments "
				  "when reducing");

		list_iterate_items(seg, &lv->segments) {
			seg_extents = seg->len;

			if (seg->segtype->flags & SEG_AREAS_STRIPED) {
				seg_stripesize = seg->stripe_size;
				seg_stripes = seg->area_count;
			}

			if (lp->extents <= extents_used + seg_extents)
				break;

			extents_used += seg_extents;
		}

		seg_size = lp->extents - extents_used;
		lp->stripe_size = seg_stripesize;
		lp->stripes = seg_stripes;
	}

	if (lp->stripes > 1 && !lp->stripe_size) {
		log_error("Stripesize for striped segment should not be 0!");
		return EINVALID_CMD_LINE;
	}

	if ((lp->stripes > 1)) {
		if (!(stripesize_extents = lp->stripe_size / vg->extent_size))
			stripesize_extents = 1;

		if ((size_rest = seg_size % (lp->stripes * stripesize_extents))) {
			log_print("Rounding size (%d extents) down to stripe "
				  "boundary size for segment (%d extents)",
				  lp->extents, lp->extents - size_rest);
			lp->extents = lp->extents - size_rest;
		}
	}

	if (lp->extents == lv->le_count) {
		log_error("New size (%d extents) matches existing size "
			  "(%d extents)", lp->extents, lv->le_count);
		return EINVALID_CMD_LINE;
	}

	if (lp->extents < lv->le_count) {
		if (lp->resize == LV_EXTEND) {
			log_error("New size given (%d extents) not larger "
				  "than existing size (%d extents)",
				  lp->extents, lv->le_count);
			return EINVALID_CMD_LINE;
		} else
			lp->resize = LV_REDUCE;
	}

	if (lp->extents > lv->le_count) {
		if (lp->resize == LV_REDUCE) {
			log_error("New size given (%d extents) not less than "
				  "existing size (%d extents)", lp->extents,
				  lv->le_count);
			return EINVALID_CMD_LINE;
		} else
			lp->resize = LV_EXTEND;
	}

	if (lp->resize == LV_REDUCE) {
		if (lp->argc)
			log_print("Ignoring PVs on command line when reducing");

		memset(&info, 0, sizeof(info));

		if (!lv_info(lv, &info) && driver_version(NULL, 0)) {
			log_error("lv_info failed: aborting");
			return ECMD_FAILED;
		}

		if (info.exists) {
			log_print("WARNING: Reducing active%s logical volume "
				  "to %s", info.open_count ? " and open" : "",
				  display_size(cmd, (uint64_t) lp->extents *
						    (vg->extent_size / 2),
					       SIZE_SHORT));

			log_print("THIS MAY DESTROY YOUR DATA "
				  "(filesystem etc.)");
		}

		if (!arg_count(cmd, force_ARG)) {
			if (yes_no_prompt("Do you really want to reduce %s?"
					  " [y/n]: ", lp->lv_name) == 'n') {
				log_print("Logical volume %s NOT reduced",
					  lp->lv_name);
				return ECMD_FAILED;
			}
		}

		if (!archive(vg)) {
			stack;
			return ECMD_FAILED;
		}

		if (!lv_reduce(vg->fid, lv, lv->le_count - lp->extents))
			return ECMD_FAILED;
	}

	if (lp->resize == LV_EXTEND) {
		if (!(pvh = lp->argc ? create_pv_list(cmd->mem, vg, lp->argc,
						      lp->argv) : &vg->pvs)) {
			stack;
			return ECMD_FAILED;
		}

		if (!archive(vg)) {
			stack;
			return ECMD_FAILED;
		}

		log_print("Extending logical volume %s to %s", lp->lv_name,
			  display_size(cmd, (uint64_t)
				       lp->extents * (vg->extent_size / 2),
				       SIZE_SHORT));

		if (!lv_extend(vg->fid, lv, lp->segtype, lp->stripes,
			       lp->stripe_size, 0u,
			       lp->extents - lv->le_count,
			       NULL, 0u, 0u, pvh, alloc)) {
			stack;
			return ECMD_FAILED;
		}
	}

	/* store vg on disk(s) */
	if (!vg_write(vg)) {
		stack;
		return ECMD_FAILED;
	}

	backup(vg);

	/* If snapshot, must suspend all associated devices */
	if ((snap = find_cow(lv)))
		lock_lvid = snap->origin->lvid.s;
	else
		lock_lvid = lv->lvid.s;

	if (!suspend_lv(cmd, lock_lvid)) {
		log_error("Failed to suspend %s", lp->lv_name);
		vg_revert(vg);
		return ECMD_FAILED;
	}

	if (!vg_commit(vg)) {
		stack;
		resume_lv(cmd, lock_lvid);
		return ECMD_FAILED;
	}

	if (!resume_lv(cmd, lock_lvid)) {
		log_error("Problem reactivating %s", lp->lv_name);
		return ECMD_FAILED;
	}

	log_print("Logical volume %s successfully resized", lp->lv_name);

	return ECMD_PROCESSED;
}

int lvresize(struct cmd_context *cmd, int argc, char **argv)
{
	struct lvresize_params lp;
	int r;

	memset(&lp, 0, sizeof(lp));

	if (!_read_params(cmd, argc, argv, &lp))
		return EINVALID_CMD_LINE;

	log_verbose("Finding volume group %s", lp.vg_name);
	if (!lock_vol(cmd, lp.vg_name, LCK_VG_WRITE)) {
		log_error("Can't get lock for %s", lp.vg_name);
		return ECMD_FAILED;
	}

	if (!(r = _lvresize(cmd, &lp)))
		stack;

	unlock_vg(cmd, lp.vg_name);

	return r;
}
