/*
* 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) 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2018 by Delphix. All rights reserved.
* Copyright (c) 2019, loli10K <ezomori.nozomu@gmail.com>. All rights reserved.
*/
#include <sys/dmu.h>
#include <sys/dmu_impl.h>
#include <sys/dmu_tx.h>
#include <sys/dbuf.h>
#include <sys/dnode.h>
#include <sys/zfs_context.h>
#include <sys/dmu_objset.h>
#include <sys/dmu_traverse.h>
#include <sys/dsl_dataset.h>
#include <sys/dsl_dir.h>
#include <sys/dsl_pool.h>
#include <sys/dsl_synctask.h>
#include <sys/zfs_ioctl.h>
#include <sys/zap.h>
#include <sys/zio_checksum.h>
#include <sys/zfs_znode.h>
#include <sys/zfs_file.h>
typedef struct dmu_diffarg {
zfs_file_t *da_fp; /* file to which we are reporting */
offset_t *da_offp;
int da_err; /* error that stopped diff search */
dmu_diff_record_t da_ddr;
} dmu_diffarg_t;
static int
write_record(dmu_diffarg_t *da)
{
zfs_file_t *fp;
ssize_t resid;
if (da->da_ddr.ddr_type == DDR_NONE) {
da->da_err = 0;
return (0);
}
fp = da->da_fp;
da->da_err = zfs_file_write(fp, (caddr_t)&da->da_ddr,
sizeof (da->da_ddr), &resid);
*da->da_offp += sizeof (da->da_ddr);
return (da->da_err);
}
static int
report_free_dnode_range(dmu_diffarg_t *da, uint64_t first, uint64_t last)
{
ASSERT(first <= last);
if (da->da_ddr.ddr_type != DDR_FREE ||
first != da->da_ddr.ddr_last + 1) {
if (write_record(da) != 0)
return (da->da_err);
da->da_ddr.ddr_type = DDR_FREE;
da->da_ddr.ddr_first = first;
da->da_ddr.ddr_last = last;
return (0);
}
da->da_ddr.ddr_last = last;
return (0);
}
static int
report_dnode(dmu_diffarg_t *da, uint64_t object, dnode_phys_t *dnp)
{
ASSERT(dnp != NULL);
if (dnp->dn_type == DMU_OT_NONE)
return (report_free_dnode_range(da, object, object));
if (da->da_ddr.ddr_type != DDR_INUSE ||
object != da->da_ddr.ddr_last + 1) {
if (write_record(da) != 0)
return (da->da_err);
da->da_ddr.ddr_type = DDR_INUSE;
da->da_ddr.ddr_first = da->da_ddr.ddr_last = object;
return (0);
}
da->da_ddr.ddr_last = object;
return (0);
}
#define DBP_SPAN(dnp, level) \
(((uint64_t)dnp->dn_datablkszsec) << (SPA_MINBLOCKSHIFT + \
(level) * (dnp->dn_indblkshift - SPA_BLKPTRSHIFT)))
/* ARGSUSED */
static int
diff_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp,
const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg)
{
dmu_diffarg_t *da = arg;
int err = 0;
if (issig(JUSTLOOKING) && issig(FORREAL))
return (SET_ERROR(EINTR));
if (zb->zb_level == ZB_DNODE_LEVEL ||
zb->zb_object != DMU_META_DNODE_OBJECT)
return (0);
if (BP_IS_HOLE(bp)) {
uint64_t span = DBP_SPAN(dnp, zb->zb_level);
uint64_t dnobj = (zb->zb_blkid * span) >> DNODE_SHIFT;
err = report_free_dnode_range(da, dnobj,
dnobj + (span >> DNODE_SHIFT) - 1);
if (err)
return (err);
} else if (zb->zb_level == 0) {
dnode_phys_t *blk;
arc_buf_t *abuf;
arc_flags_t aflags = ARC_FLAG_WAIT;
int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT;
int zio_flags = ZIO_FLAG_CANFAIL;
int i;
if (BP_IS_PROTECTED(bp))
zio_flags |= ZIO_FLAG_RAW;
if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf,
ZIO_PRIORITY_ASYNC_READ, zio_flags, &aflags, zb) != 0)
return (SET_ERROR(EIO));
blk = abuf->b_data;
for (i = 0; i < epb; i += blk[i].dn_extra_slots + 1) {
uint64_t dnobj = (zb->zb_blkid <<
(DNODE_BLOCK_SHIFT - DNODE_SHIFT)) + i;
err = report_dnode(da, dnobj, blk+i);
if (err)
break;
}
arc_buf_destroy(abuf, &abuf);
if (err)
return (err);
/* Don't care about the data blocks */
return (TRAVERSE_VISIT_NO_CHILDREN);
}
return (0);
}
int
dmu_diff(const char *tosnap_name, const char *fromsnap_name,
zfs_file_t *fp, offset_t *offp)
{
dmu_diffarg_t da;
dsl_dataset_t *fromsnap;
dsl_dataset_t *tosnap;
dsl_pool_t *dp;
int error;
uint64_t fromtxg;
if (strchr(tosnap_name, '@') == NULL ||
strchr(fromsnap_name, '@') == NULL)
return (SET_ERROR(EINVAL));
error = dsl_pool_hold(tosnap_name, FTAG, &dp);
if (error != 0)
return (error);
error = dsl_dataset_hold(dp, tosnap_name, FTAG, &tosnap);
if (error != 0) {
dsl_pool_rele(dp, FTAG);
return (error);
}
error = dsl_dataset_hold(dp, fromsnap_name, FTAG, &fromsnap);
if (error != 0) {
dsl_dataset_rele(tosnap, FTAG);
dsl_pool_rele(dp, FTAG);
return (error);
}
if (!dsl_dataset_is_before(tosnap, fromsnap, 0)) {
dsl_dataset_rele(fromsnap, FTAG);
dsl_dataset_rele(tosnap, FTAG);
dsl_pool_rele(dp, FTAG);
return (SET_ERROR(EXDEV));
}
fromtxg = dsl_dataset_phys(fromsnap)->ds_creation_txg;
dsl_dataset_rele(fromsnap, FTAG);
dsl_dataset_long_hold(tosnap, FTAG);
dsl_pool_rele(dp, FTAG);
da.da_fp = fp;
da.da_offp = offp;
da.da_ddr.ddr_type = DDR_NONE;
da.da_ddr.ddr_first = da.da_ddr.ddr_last = 0;
da.da_err = 0;
/*
* Since zfs diff only looks at dnodes which are stored in plaintext
* (other than bonus buffers), we don't technically need to decrypt
* the dataset to perform this operation. However, the command line
* utility will still fail if the keys are not loaded because the
* dataset isn't mounted and because it will fail when it attempts to
* call the ZFS_IOC_OBJ_TO_STATS ioctl.
*/
error = traverse_dataset(tosnap, fromtxg,
TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA | TRAVERSE_NO_DECRYPT,
diff_cb, &da);
if (error != 0) {
da.da_err = error;
} else {
/* we set the da.da_err we return as side-effect */
(void) write_record(&da);
}
dsl_dataset_long_rele(tosnap, FTAG);
dsl_dataset_rele(tosnap, FTAG);
return (da.da_err);
}
