/*

 * 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.

 */

#include <sys/bpobj.h>

#include <sys/zfs_context.h>

#include <sys/refcount.h>

uint64_t

bpobj_alloc(objset_t *os, int blocksize, dmu_tx_t *tx)

{

	int size;

	if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_BPOBJ_ACCOUNT)

		size = BPOBJ_SIZE_V0;

	else if (spa_version(dmu_objset_spa(os)) < SPA_VERSION_DEADLISTS)

		size = BPOBJ_SIZE_V1;

	else

		size = sizeof (bpobj_phys_t);

	return (dmu_object_alloc(os, DMU_OT_BPOBJ, blocksize,

	    DMU_OT_BPOBJ_HDR, size, tx));

}

void

bpobj_free(objset_t *os, uint64_t obj, dmu_tx_t *tx)

{

	int64_t i;

	bpobj_t bpo;

	dmu_object_info_t doi;

	int epb;

	dmu_buf_t *dbuf = NULL;

	VERIFY3U(0, ==, bpobj_open(&bpo, os, obj));

	mutex_enter(&bpo.bpo_lock);

	if (!bpo.bpo_havesubobj || bpo.bpo_phys->bpo_subobjs == 0)

		goto out;

	VERIFY3U(0, ==, dmu_object_info(os, bpo.bpo_phys->bpo_subobjs, &doi));

	epb = doi.doi_data_block_size / sizeof (uint64_t);

	for (i = bpo.bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {

		uint64_t *objarray;

		uint64_t offset, blkoff;

		offset = i * sizeof (uint64_t);

		blkoff = P2PHASE(i, epb);

		if (dbuf == NULL || dbuf->db_offset > offset) {

			if (dbuf)

				dmu_buf_rele(dbuf, FTAG);

			VERIFY3U(0, ==, dmu_buf_hold(os,

			    bpo.bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0));

		}

		ASSERT3U(offset, >=, dbuf->db_offset);

		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);

		objarray = dbuf->db_data;

		bpobj_free(os, objarray[blkoff], tx);

	}

	if (dbuf) {

		dmu_buf_rele(dbuf, FTAG);

		dbuf = NULL;

	}

	VERIFY3U(0, ==, dmu_object_free(os, bpo.bpo_phys->bpo_subobjs, tx));

out:

	mutex_exit(&bpo.bpo_lock);

	bpobj_close(&bpo);

	VERIFY3U(0, ==, dmu_object_free(os, obj, tx));

}

int

bpobj_open(bpobj_t *bpo, objset_t *os, uint64_t object)

{

	dmu_object_info_t doi;

	int err;

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

	if (err)

		return (err);

	bzero(bpo, sizeof (*bpo));

	mutex_init(&bpo->bpo_lock, NULL, MUTEX_DEFAULT, NULL);

	ASSERT(bpo->bpo_dbuf == NULL);

	ASSERT(bpo->bpo_phys == NULL);

	ASSERT(object != 0);

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

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

	bpo->bpo_os = os;

	bpo->bpo_object = object;

	bpo->bpo_epb = doi.doi_data_block_size >> SPA_BLKPTRSHIFT;

	bpo->bpo_havecomp = (doi.doi_bonus_size > BPOBJ_SIZE_V0);

	bpo->bpo_havesubobj = (doi.doi_bonus_size > BPOBJ_SIZE_V1);

	bpo->bpo_phys = bpo->bpo_dbuf->db_data;

	return (0);

}

void

bpobj_close(bpobj_t *bpo)

{

	/* Lame workaround for closing a bpobj that was never opened. */

	if (bpo->bpo_object == 0)

		return;

	dmu_buf_rele(bpo->bpo_dbuf, bpo);

	if (bpo->bpo_cached_dbuf != NULL)

		dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);

	bpo->bpo_dbuf = NULL;

	bpo->bpo_phys = NULL;

	bpo->bpo_cached_dbuf = NULL;

	mutex_destroy(&bpo->bpo_lock);

}

static int

bpobj_iterate_impl(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx,

    boolean_t free)

{

	dmu_object_info_t doi;

	int epb;

	int64_t i;

	int err = 0;

	dmu_buf_t *dbuf = NULL;

	mutex_enter(&bpo->bpo_lock);

	if (free)

		dmu_buf_will_dirty(bpo->bpo_dbuf, tx);

	for (i = bpo->bpo_phys->bpo_num_blkptrs - 1; i >= 0; i--) {

		blkptr_t *bparray;

		blkptr_t *bp;

		uint64_t offset, blkoff;

		offset = i * sizeof (blkptr_t);

		blkoff = P2PHASE(i, bpo->bpo_epb);

		if (dbuf == NULL || dbuf->db_offset > offset) {

			if (dbuf)

				dmu_buf_rele(dbuf, FTAG);

			err = dmu_buf_hold(bpo->bpo_os, bpo->bpo_object, offset,

			    FTAG, &dbuf, 0);

			if (err)

				break;

		}

		ASSERT3U(offset, >=, dbuf->db_offset);

		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);

		bparray = dbuf->db_data;

		bp = &bparray[blkoff];

		err = func(arg, bp, tx);

		if (err)

			break;

		if (free) {

			bpo->bpo_phys->bpo_bytes -=

			    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);

			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);

			if (bpo->bpo_havecomp) {

				bpo->bpo_phys->bpo_comp -= BP_GET_PSIZE(bp);

				bpo->bpo_phys->bpo_uncomp -= BP_GET_UCSIZE(bp);

			}

			bpo->bpo_phys->bpo_num_blkptrs--;

			ASSERT3S(bpo->bpo_phys->bpo_num_blkptrs, >=, 0);

		}

	}

	if (dbuf) {

		dmu_buf_rele(dbuf, FTAG);

		dbuf = NULL;

	}

	if (free) {

		i++;

		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os, bpo->bpo_object,

		    i * sizeof (blkptr_t), -1ULL, tx));

	}

	if (err || !bpo->bpo_havesubobj || bpo->bpo_phys->bpo_subobjs == 0)

		goto out;

	ASSERT(bpo->bpo_havecomp);

	err = dmu_object_info(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs, &doi);

	if (err) {

		mutex_exit(&bpo->bpo_lock);

		return (err);

	}

	epb = doi.doi_data_block_size / sizeof (uint64_t);

	for (i = bpo->bpo_phys->bpo_num_subobjs - 1; i >= 0; i--) {

		uint64_t *objarray;

		uint64_t offset, blkoff;

		bpobj_t sublist;

		uint64_t used_before, comp_before, uncomp_before;

		uint64_t used_after, comp_after, uncomp_after;

		offset = i * sizeof (uint64_t);

		blkoff = P2PHASE(i, epb);

		if (dbuf == NULL || dbuf->db_offset > offset) {

			if (dbuf)

				dmu_buf_rele(dbuf, FTAG);

			err = dmu_buf_hold(bpo->bpo_os,

			    bpo->bpo_phys->bpo_subobjs, offset, FTAG, &dbuf, 0);

			if (err)

				break;

		}

		ASSERT3U(offset, >=, dbuf->db_offset);

		ASSERT3U(offset, <, dbuf->db_offset + dbuf->db_size);

		objarray = dbuf->db_data;

		err = bpobj_open(&sublist, bpo->bpo_os, objarray[blkoff]);

		if (err)

			break;

		if (free) {

			err = bpobj_space(&sublist,

			    &used_before, &comp_before, &uncomp_before);

			if (err)

				break;

		}

		err = bpobj_iterate_impl(&sublist, func, arg, tx, free);

		if (free) {

			VERIFY3U(0, ==, bpobj_space(&sublist,

			    &used_after, &comp_after, &uncomp_after));

			bpo->bpo_phys->bpo_bytes -= used_before - used_after;

			ASSERT3S(bpo->bpo_phys->bpo_bytes, >=, 0);

			bpo->bpo_phys->bpo_comp -= comp_before - used_after;

			bpo->bpo_phys->bpo_uncomp -=

			    uncomp_before - uncomp_after;

		}

		bpobj_close(&sublist);

		if (err)

			break;

		if (free) {

			err = dmu_object_free(bpo->bpo_os,

			    objarray[blkoff], tx);

			if (err)

				break;

			bpo->bpo_phys->bpo_num_subobjs--;

			ASSERT3S(bpo->bpo_phys->bpo_num_subobjs, >=, 0);

		}

	}

	if (dbuf) {

		dmu_buf_rele(dbuf, FTAG);

		dbuf = NULL;

	}

	if (free) {

		VERIFY3U(0, ==, dmu_free_range(bpo->bpo_os,

		    bpo->bpo_phys->bpo_subobjs,

		    (i + 1) * sizeof (uint64_t), -1ULL, tx));

	}

out:

	/* If there are no entries, there should be no bytes. */

	ASSERT(bpo->bpo_phys->bpo_num_blkptrs > 0 ||

	    (bpo->bpo_havesubobj && bpo->bpo_phys->bpo_num_subobjs > 0) ||

	    bpo->bpo_phys->bpo_bytes == 0);

	mutex_exit(&bpo->bpo_lock);

	return (err);

}

/*

 * Iterate and remove the entries.  If func returns nonzero, iteration

 * will stop and that entry will not be removed.

 */

int

bpobj_iterate(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)

{

	return (bpobj_iterate_impl(bpo, func, arg, tx, B_TRUE));

}

/*

 * Iterate the entries.  If func returns nonzero, iteration will stop.

 */

int

bpobj_iterate_nofree(bpobj_t *bpo, bpobj_itor_t func, void *arg, dmu_tx_t *tx)

{

	return (bpobj_iterate_impl(bpo, func, arg, tx, B_FALSE));

}

void

bpobj_enqueue_subobj(bpobj_t *bpo, uint64_t subobj, dmu_tx_t *tx)

{

	bpobj_t subbpo;

	uint64_t used, comp, uncomp;

	ASSERT(bpo->bpo_havesubobj);

	ASSERT(bpo->bpo_havecomp);

	VERIFY3U(0, ==, bpobj_open(&subbpo, bpo->bpo_os, subobj));

	VERIFY3U(0, ==, bpobj_space(&subbpo, &used, &comp, &uncomp));

	bpobj_close(&subbpo);

	if (used == 0) {

		/* No point in having an empty subobj. */

		bpobj_free(bpo->bpo_os, subobj, tx);

		return;

	}

	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);

	if (bpo->bpo_phys->bpo_subobjs == 0) {

		bpo->bpo_phys->bpo_subobjs = dmu_object_alloc(bpo->bpo_os,

		    DMU_OT_BPOBJ_SUBOBJ, SPA_MAXBLOCKSIZE, DMU_OT_NONE, 0, tx);

	}

	mutex_enter(&bpo->bpo_lock);

	dmu_write(bpo->bpo_os, bpo->bpo_phys->bpo_subobjs,

	    bpo->bpo_phys->bpo_num_subobjs * sizeof (subobj),

	    sizeof (subobj), &subobj, tx);

	bpo->bpo_phys->bpo_num_subobjs++;

	bpo->bpo_phys->bpo_bytes += used;

	bpo->bpo_phys->bpo_comp += comp;

	bpo->bpo_phys->bpo_uncomp += uncomp;

	mutex_exit(&bpo->bpo_lock);

}

void

bpobj_enqueue(bpobj_t *bpo, const blkptr_t *bp, dmu_tx_t *tx)

{

	blkptr_t stored_bp = *bp;

	uint64_t offset;

	int blkoff;

	blkptr_t *bparray;

	ASSERT(!BP_IS_HOLE(bp));

	/* We never need the fill count. */

	stored_bp.blk_fill = 0;

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

	if (!BP_GET_DEDUP(bp))

		bzero(&stored_bp.blk_cksum, sizeof (stored_bp.blk_cksum));

	mutex_enter(&bpo->bpo_lock);

	offset = bpo->bpo_phys->bpo_num_blkptrs * sizeof (stored_bp);

	blkoff = P2PHASE(bpo->bpo_phys->bpo_num_blkptrs, bpo->bpo_epb);

	if (bpo->bpo_cached_dbuf == NULL ||

	    offset < bpo->bpo_cached_dbuf->db_offset ||

	    offset >= bpo->bpo_cached_dbuf->db_offset +

	    bpo->bpo_cached_dbuf->db_size) {

		if (bpo->bpo_cached_dbuf)

			dmu_buf_rele(bpo->bpo_cached_dbuf, bpo);

		VERIFY3U(0, ==, dmu_buf_hold(bpo->bpo_os, bpo->bpo_object,

		    offset, bpo, &bpo->bpo_cached_dbuf, 0));

	}

	dmu_buf_will_dirty(bpo->bpo_cached_dbuf, tx);

	bparray = bpo->bpo_cached_dbuf->db_data;

	bparray[blkoff] = stored_bp;

	dmu_buf_will_dirty(bpo->bpo_dbuf, tx);

	bpo->bpo_phys->bpo_num_blkptrs++;

	bpo->bpo_phys->bpo_bytes +=

	    bp_get_dsize_sync(dmu_objset_spa(bpo->bpo_os), bp);

	if (bpo->bpo_havecomp) {

		bpo->bpo_phys->bpo_comp += BP_GET_PSIZE(bp);

		bpo->bpo_phys->bpo_uncomp += BP_GET_UCSIZE(bp);

	}

	mutex_exit(&bpo->bpo_lock);

}

struct space_range_arg {

	spa_t *spa;

	uint64_t mintxg;

	uint64_t maxtxg;

	uint64_t used;

	uint64_t comp;

	uint64_t uncomp;

};

/* ARGSUSED */

static int

space_range_cb(void *arg, const blkptr_t *bp, dmu_tx_t *tx)

{

	struct space_range_arg *sra = arg;

	if (bp->blk_birth > sra->mintxg && bp->blk_birth <= sra->maxtxg) {

		sra->used += bp_get_dsize_sync(sra->spa, bp);

		sra->comp += BP_GET_PSIZE(bp);

		sra->uncomp += BP_GET_UCSIZE(bp);

	}

	return (0);

}

int

bpobj_space(bpobj_t *bpo, uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)

{

	mutex_enter(&bpo->bpo_lock);

	*usedp = bpo->bpo_phys->bpo_bytes;

	if (bpo->bpo_havecomp) {

		*compp = bpo->bpo_phys->bpo_comp;

		*uncompp = bpo->bpo_phys->bpo_uncomp;

		mutex_exit(&bpo->bpo_lock);

		return (0);

	} else {

		mutex_exit(&bpo->bpo_lock);

		return (bpobj_space_range(bpo, 0, UINT64_MAX,

		    usedp, compp, uncompp));

	}

}

/*

 * Return the amount of space in the bpobj which is:

 * mintxg < blk_birth <= maxtxg

 */

int

bpobj_space_range(bpobj_t *bpo, uint64_t mintxg, uint64_t maxtxg,

    uint64_t *usedp, uint64_t *compp, uint64_t *uncompp)

{

	struct space_range_arg sra = { 0 };

	int err;

	/*

	 * As an optimization, if they want the whole txg range, just

	 * get bpo_bytes rather than iterating over the bps.

	 */

	if (mintxg < TXG_INITIAL && maxtxg == UINT64_MAX && bpo->bpo_havecomp)

		return (bpobj_space(bpo, usedp, compp, uncompp));

	sra.spa = dmu_objset_spa(bpo->bpo_os);

	sra.mintxg = mintxg;

	sra.maxtxg = maxtxg;

	err = bpobj_iterate_nofree(bpo, space_range_cb, &sra, NULL);

	*usedp = sra.used;

	*compp = sra.comp;

	*uncompp = sra.uncomp;

	return (err);

}