/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/bplist.h>

#include <sys/zfs_context.h>

static int

bplist_hold(bplist_t *bpl)

{

	ASSERT(MUTEX_HELD(&bpl->bpl_lock));

	if (bpl->bpl_dbuf == NULL) {

		int err = dmu_bonus_hold(bpl->bpl_mos,

		    bpl->bpl_object, bpl, &bpl->bpl_dbuf);

		if (err)

			return (err);

		bpl->bpl_phys = bpl->bpl_dbuf->db_data;

	}

	return (0);

}

uint64_t

bplist_create(objset_t *mos, int blocksize, dmu_tx_t *tx)

{

	int size;

	size = spa_version(dmu_objset_spa(mos)) < SPA_VERSION_BPLIST_ACCOUNT ?

	    BPLIST_SIZE_V0 : sizeof (bplist_phys_t);

	return (dmu_object_alloc(mos, DMU_OT_BPLIST, blocksize,

	    DMU_OT_BPLIST_HDR, size, tx));

}

void

bplist_destroy(objset_t *mos, uint64_t object, dmu_tx_t *tx)

{

	VERIFY(dmu_object_free(mos, object, tx) == 0);

}

int

bplist_open(bplist_t *bpl, objset_t *mos, uint64_t object)

{

	dmu_object_info_t doi;

	int err;

	err = dmu_object_info(mos, object, &doi);

	if (err)

		return (err);

	mutex_enter(&bpl->bpl_lock);

	ASSERT(bpl->bpl_dbuf == NULL);

	ASSERT(bpl->bpl_phys == NULL);

	ASSERT(bpl->bpl_cached_dbuf == NULL);

	ASSERT(bpl->bpl_queue == NULL);

	ASSERT(object != 0);

	ASSERT3U(doi.doi_type, ==, DMU_OT_BPLIST);

	ASSERT3U(doi.doi_bonus_type, ==, DMU_OT_BPLIST_HDR);

	bpl->bpl_mos = mos;

	bpl->bpl_object = object;

	bpl->bpl_blockshift = highbit(doi.doi_data_block_size - 1);

	bpl->bpl_bpshift = bpl->bpl_blockshift - SPA_BLKPTRSHIFT;

	bpl->bpl_havecomp = (doi.doi_bonus_size == sizeof (bplist_phys_t));

	mutex_exit(&bpl->bpl_lock);

	return (0);

}

void

bplist_close(bplist_t *bpl)

{

	mutex_enter(&bpl->bpl_lock);

	ASSERT(bpl->bpl_queue == NULL);

	if (bpl->bpl_cached_dbuf) {

		dmu_buf_rele(bpl->bpl_cached_dbuf, bpl);

		bpl->bpl_cached_dbuf = NULL;

	}

	if (bpl->bpl_dbuf) {

		dmu_buf_rele(bpl->bpl_dbuf, bpl);

		bpl->bpl_dbuf = NULL;

		bpl->bpl_phys = NULL;

	}

	mutex_exit(&bpl->bpl_lock);

}

boolean_t

bplist_empty(bplist_t *bpl)

{

	boolean_t rv;

	if (bpl->bpl_object == 0)

		return (B_TRUE);

	mutex_enter(&bpl->bpl_lock);

	VERIFY(0 == bplist_hold(bpl)); /* XXX */

	rv = (bpl->bpl_phys->bpl_entries == 0);

	mutex_exit(&bpl->bpl_lock);

	return (rv);

}

static int

bplist_cache(bplist_t *bpl, uint64_t blkid)

{

	int err = 0;

	if (bpl->bpl_cached_dbuf == NULL ||

	    bpl->bpl_cached_dbuf->db_offset != (blkid << bpl->bpl_blockshift)) {

		if (bpl->bpl_cached_dbuf != NULL)

			dmu_buf_rele(bpl->bpl_cached_dbuf, bpl);

		err = dmu_buf_hold(bpl->bpl_mos,

		    bpl->bpl_object, blkid << bpl->bpl_blockshift,

		    bpl, &bpl->bpl_cached_dbuf);

		ASSERT(err || bpl->bpl_cached_dbuf->db_size ==

		    1ULL << bpl->bpl_blockshift);

	}

	return (err);

}

int

bplist_iterate(bplist_t *bpl, uint64_t *itorp, blkptr_t *bp)

{

	uint64_t blk, off;

	blkptr_t *bparray;

	int err;

	mutex_enter(&bpl->bpl_lock);

	err = bplist_hold(bpl);

	if (err) {

		mutex_exit(&bpl->bpl_lock);

		return (err);

	}

	if (*itorp >= bpl->bpl_phys->bpl_entries) {

		mutex_exit(&bpl->bpl_lock);

		return (ENOENT);

	}

	blk = *itorp >> bpl->bpl_bpshift;

	off = P2PHASE(*itorp, 1ULL << bpl->bpl_bpshift);

	err = bplist_cache(bpl, blk);

	if (err) {

		mutex_exit(&bpl->bpl_lock);

		return (err);

	}

	bparray = bpl->bpl_cached_dbuf->db_data;

	*bp = bparray[off];

	(*itorp)++;

	mutex_exit(&bpl->bpl_lock);

	return (0);

}

int

bplist_enqueue(bplist_t *bpl, blkptr_t *bp, dmu_tx_t *tx)

{

	uint64_t blk, off;

	blkptr_t *bparray;

	int err;

	ASSERT(!BP_IS_HOLE(bp));

	mutex_enter(&bpl->bpl_lock);

	err = bplist_hold(bpl);

	if (err)

		return (err);

	blk = bpl->bpl_phys->bpl_entries >> bpl->bpl_bpshift;

	off = P2PHASE(bpl->bpl_phys->bpl_entries, 1ULL << bpl->bpl_bpshift);

	err = bplist_cache(bpl, blk);

	if (err) {

		mutex_exit(&bpl->bpl_lock);

		return (err);

	}

	dmu_buf_will_dirty(bpl->bpl_cached_dbuf, tx);

	bparray = bpl->bpl_cached_dbuf->db_data;

	bparray[off] = *bp;

	/* We never need the fill count. */

	bparray[off].blk_fill = 0;

	/* The bplist will compress better if we can leave off the checksum */

	bzero(&bparray[off].blk_cksum, sizeof (bparray[off].blk_cksum));

	dmu_buf_will_dirty(bpl->bpl_dbuf, tx);

	bpl->bpl_phys->bpl_entries++;

	bpl->bpl_phys->bpl_bytes +=

	    bp_get_dasize(dmu_objset_spa(bpl->bpl_mos), bp);

	if (bpl->bpl_havecomp) {

		bpl->bpl_phys->bpl_comp += BP_GET_PSIZE(bp);

		bpl->bpl_phys->bpl_uncomp += BP_GET_UCSIZE(bp);

	}

	mutex_exit(&bpl->bpl_lock);

	return (0);

}

/*

 * Deferred entry; will be written later by bplist_sync().

 */

void

bplist_enqueue_deferred(bplist_t *bpl, blkptr_t *bp)

{

	bplist_q_t *bpq = kmem_alloc(sizeof (*bpq), KM_SLEEP);

	ASSERT(!BP_IS_HOLE(bp));

	mutex_enter(&bpl->bpl_lock);

	bpq->bpq_blk = *bp;

	bpq->bpq_next = bpl->bpl_queue;

	bpl->bpl_queue = bpq;

	mutex_exit(&bpl->bpl_lock);

}

void

bplist_sync(bplist_t *bpl, dmu_tx_t *tx)

{

	bplist_q_t *bpq;

	mutex_enter(&bpl->bpl_lock);

	while ((bpq = bpl->bpl_queue) != NULL) {

		bpl->bpl_queue = bpq->bpq_next;

		mutex_exit(&bpl->bpl_lock);

		VERIFY(0 == bplist_enqueue(bpl, &bpq->bpq_blk, tx));

		kmem_free(bpq, sizeof (*bpq));

		mutex_enter(&bpl->bpl_lock);

	}

	mutex_exit(&bpl->bpl_lock);

}

void

bplist_vacate(bplist_t *bpl, dmu_tx_t *tx)

{

	mutex_enter(&bpl->bpl_lock);

	ASSERT3P(bpl->bpl_queue, ==, NULL);

	VERIFY(0 == bplist_hold(bpl));

	dmu_buf_will_dirty(bpl->bpl_dbuf, tx);

	VERIFY(0 == dmu_free_range(bpl->bpl_mos,

	    bpl->bpl_object, 0, -1ULL, tx));

	bpl->bpl_phys->bpl_entries = 0;

	bpl->bpl_phys->bpl_bytes = 0;

	if (bpl->bpl_havecomp) {

		bpl->bpl_phys->bpl_comp = 0;

		bpl->bpl_phys->bpl_uncomp = 0;

	}

	mutex_exit(&bpl->bpl_lock);

}

int

bplist_space(bplist_t *bpl, uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)

{

	int err;

	mutex_enter(&bpl->bpl_lock);

	err = bplist_hold(bpl);

	if (err) {

		mutex_exit(&bpl->bpl_lock);

		return (err);

	}

	*usedp = bpl->bpl_phys->bpl_bytes;

	if (bpl->bpl_havecomp) {

		*compp = bpl->bpl_phys->bpl_comp;

		*uncompp = bpl->bpl_phys->bpl_uncomp;

	}

	mutex_exit(&bpl->bpl_lock);

	if (!bpl->bpl_havecomp) {

		uint64_t itor = 0, comp = 0, uncomp = 0;

		blkptr_t bp;

		while ((err = bplist_iterate(bpl, &itor, &bp)) == 0) {

			comp += BP_GET_PSIZE(&bp);

			uncomp += BP_GET_UCSIZE(&bp);

		}

		if (err == ENOENT)

			err = 0;

		*compp = comp;

		*uncompp = uncomp;

	}

	return (err);

}