diff options
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c')
-rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c new file mode 100644 index 000000000000..e7bfdaa90e97 --- /dev/null +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_diff.c @@ -0,0 +1,251 @@ +/* + * 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, 2015 by Delphix. 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> + +struct diffarg { + struct file *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; + kthread_t *da_td; +}; + +static int +write_bytes(struct diffarg *da) +{ + struct uio auio; + struct iovec aiov; + + aiov.iov_base = (caddr_t)&da->da_ddr; + aiov.iov_len = sizeof (da->da_ddr); + auio.uio_iov = &aiov; + auio.uio_iovcnt = 1; + auio.uio_resid = aiov.iov_len; + auio.uio_segflg = UIO_SYSSPACE; + auio.uio_rw = UIO_WRITE; + auio.uio_offset = (off_t)-1; + auio.uio_td = da->da_td; +#ifdef _KERNEL + if (da->da_fp->f_type == DTYPE_VNODE) + bwillwrite(); + return (fo_write(da->da_fp, &auio, da->da_td->td_ucred, 0, da->da_td)); +#else + fprintf(stderr, "%s: returning EOPNOTSUPP\n", __func__); + return (EOPNOTSUPP); +#endif +} + +static int +write_record(struct diffarg *da) +{ + + if (da->da_ddr.ddr_type == DDR_NONE) { + da->da_err = 0; + return (0); + } + + da->da_err = write_bytes(da); + *da->da_offp += sizeof (da->da_ddr); + return (da->da_err); +} + +static int +report_free_dnode_range(struct diffarg *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(struct diffarg *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) +{ + struct diffarg *da = arg; + int err = 0; + + if (issig(JUSTLOOKING) && issig(FORREAL)) + return (SET_ERROR(EINTR)); + + if (bp == NULL || 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 blksz = BP_GET_LSIZE(bp); + int i; + + if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf, + ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, + &aflags, zb) != 0) + return (SET_ERROR(EIO)); + + blk = abuf->b_data; + for (i = 0; i < blksz >> DNODE_SHIFT; i++) { + 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, +#ifdef illumos + struct vnode *vp, offset_t *offp) +#else + struct file *fp, offset_t *offp) +#endif +{ + struct diffarg 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; + da.da_td = curthread; + + error = traverse_dataset(tosnap, fromtxg, + TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, 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); +} |