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6111 zfs send should ignore datasets created after the ending snapshot
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Reviewed by: Alex Aizman [email protected]
Reviewed by: Alek Pinchuk [email protected]
Reviewed by: Roman Strashkin [email protected]
Reviewed by: Matthew Ahrens <[email protected]>
Reviewed by: Paul Dagnelie <[email protected]>
Approved by: Garrett D'Amore <[email protected]>
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@deiter @ahrens
deiter authored and ahrens committed May 11, 2016
1 parent 1fdcbd0 commit 4a20c93
Showing 1 changed file with 108 additions and 6 deletions.
114 changes: 108 additions & 6 deletions usr/src/lib/libzfs/common/libzfs_sendrecv.c
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Original file line number Diff line number Diff line change
Expand Up @@ -571,13 +571,30 @@ fsavl_create(nvlist_t *fss)
* Routines for dealing with the giant nvlist of fs-nvlists, etc.
*/
typedef struct send_data {
/*
* assigned inside every recursive call,
* restored from *_save on return:
*
* guid of fromsnap snapshot in parent dataset
* txg of fromsnap snapshot in current dataset
* txg of tosnap snapshot in current dataset
*/

uint64_t parent_fromsnap_guid;
uint64_t fromsnap_txg;
uint64_t tosnap_txg;

/* the nvlists get accumulated during depth-first traversal */
nvlist_t *parent_snaps;
nvlist_t *fss;
nvlist_t *snapprops;

/* send-receive configuration, does not change during traversal */
const char *fsname;
const char *fromsnap;
const char *tosnap;
boolean_t recursive;
boolean_t verbose;

/*
* The header nvlist is of the following format:
Expand Down Expand Up @@ -610,11 +627,23 @@ send_iterate_snap(zfs_handle_t *zhp, void *arg)
{
send_data_t *sd = arg;
uint64_t guid = zhp->zfs_dmustats.dds_guid;
uint64_t txg = zhp->zfs_dmustats.dds_creation_txg;
char *snapname;
nvlist_t *nv;

snapname = strrchr(zhp->zfs_name, '@')+1;

if (sd->tosnap_txg != 0 && txg > sd->tosnap_txg) {
if (sd->verbose) {
(void) fprintf(stderr, dgettext(TEXT_DOMAIN,
"skipping snapshot %s because it was created "
"after the destination snapshot (%s)\n"),
zhp->zfs_name, sd->tosnap);
}
zfs_close(zhp);
return (0);
}

VERIFY(0 == nvlist_add_uint64(sd->parent_snaps, snapname, guid));
/*
* NB: if there is no fromsnap here (it's a newly created fs in
Expand Down Expand Up @@ -707,6 +736,31 @@ send_iterate_prop(zfs_handle_t *zhp, nvlist_t *nv)
}
}

/*
* returns snapshot creation txg
* and returns 0 if the snapshot does not exist
*/
static uint64_t
get_snap_txg(libzfs_handle_t *hdl, const char *fs, const char *snap)
{
char name[ZFS_MAXNAMELEN];
uint64_t txg = 0;

if (fs == NULL || fs[0] == '\0' || snap == NULL || snap[0] == '\0')
return (txg);

(void) snprintf(name, sizeof (name), "%s@%s", fs, snap);
if (zfs_dataset_exists(hdl, name, ZFS_TYPE_SNAPSHOT)) {
zfs_handle_t *zhp = zfs_open(hdl, name, ZFS_TYPE_SNAPSHOT);
if (zhp != NULL) {
txg = zfs_prop_get_int(zhp, ZFS_PROP_CREATETXG);
zfs_close(zhp);
}
}

return (txg);
}

/*
* recursively generate nvlists describing datasets. See comment
* for the data structure send_data_t above for description of contents
Expand All @@ -719,9 +773,48 @@ send_iterate_fs(zfs_handle_t *zhp, void *arg)
nvlist_t *nvfs, *nv;
int rv = 0;
uint64_t parent_fromsnap_guid_save = sd->parent_fromsnap_guid;
uint64_t fromsnap_txg_save = sd->fromsnap_txg;
uint64_t tosnap_txg_save = sd->tosnap_txg;
uint64_t txg = zhp->zfs_dmustats.dds_creation_txg;
uint64_t guid = zhp->zfs_dmustats.dds_guid;
uint64_t fromsnap_txg, tosnap_txg;
char guidstring[64];

fromsnap_txg = get_snap_txg(zhp->zfs_hdl, zhp->zfs_name, sd->fromsnap);
if (fromsnap_txg != 0)
sd->fromsnap_txg = fromsnap_txg;

tosnap_txg = get_snap_txg(zhp->zfs_hdl, zhp->zfs_name, sd->tosnap);
if (tosnap_txg != 0)
sd->tosnap_txg = tosnap_txg;

/*
* on the send side, if the current dataset does not have tosnap,
* perform two additional checks:
*
* - skip sending the current dataset if it was created later than
* the parent tosnap
* - return error if the current dataset was created earlier than
* the parent tosnap
*/
if (sd->tosnap != NULL && tosnap_txg == 0) {
if (sd->tosnap_txg != 0 && txg > sd->tosnap_txg) {
if (sd->verbose) {
(void) fprintf(stderr, dgettext(TEXT_DOMAIN,
"skipping dataset %s: snapshot %s does "
"not exist\n"), zhp->zfs_name, sd->tosnap);
}
} else {
(void) fprintf(stderr, dgettext(TEXT_DOMAIN,
"cannot send %s@%s%s: snapshot %s@%s does not "
"exist\n"), sd->fsname, sd->tosnap, sd->recursive ?
dgettext(TEXT_DOMAIN, " recursively") : "",
zhp->zfs_name, sd->tosnap);
rv = -1;
}
goto out;
}

VERIFY(0 == nvlist_alloc(&nvfs, NV_UNIQUE_NAME, 0));
VERIFY(0 == nvlist_add_string(nvfs, "name", zhp->zfs_name));
VERIFY(0 == nvlist_add_uint64(nvfs, "parentfromsnap",
Expand All @@ -730,8 +823,10 @@ send_iterate_fs(zfs_handle_t *zhp, void *arg)
if (zhp->zfs_dmustats.dds_origin[0]) {
zfs_handle_t *origin = zfs_open(zhp->zfs_hdl,
zhp->zfs_dmustats.dds_origin, ZFS_TYPE_SNAPSHOT);
if (origin == NULL)
return (-1);
if (origin == NULL) {
rv = -1;
goto out;
}
VERIFY(0 == nvlist_add_uint64(nvfs, "origin",
origin->zfs_dmustats.dds_guid));
}
Expand Down Expand Up @@ -762,15 +857,19 @@ send_iterate_fs(zfs_handle_t *zhp, void *arg)
if (sd->recursive)
rv = zfs_iter_filesystems(zhp, send_iterate_fs, sd);

out:
sd->parent_fromsnap_guid = parent_fromsnap_guid_save;
sd->fromsnap_txg = fromsnap_txg_save;
sd->tosnap_txg = tosnap_txg_save;

zfs_close(zhp);
return (rv);
}

static int
gather_nvlist(libzfs_handle_t *hdl, const char *fsname, const char *fromsnap,
const char *tosnap, boolean_t recursive, nvlist_t **nvlp, avl_tree_t **avlp)
const char *tosnap, boolean_t recursive, boolean_t verbose,
nvlist_t **nvlp, avl_tree_t **avlp)
{
zfs_handle_t *zhp;
send_data_t sd = { 0 };
Expand All @@ -781,9 +880,11 @@ gather_nvlist(libzfs_handle_t *hdl, const char *fsname, const char *fromsnap,
return (EZFS_BADTYPE);

VERIFY(0 == nvlist_alloc(&sd.fss, NV_UNIQUE_NAME, 0));
sd.fsname = fsname;
sd.fromsnap = fromsnap;
sd.tosnap = tosnap;
sd.recursive = recursive;
sd.verbose = verbose;

if ((error = send_iterate_fs(zhp, &sd)) != 0) {
nvlist_free(sd.fss);
Expand Down Expand Up @@ -1688,7 +1789,8 @@ zfs_send(zfs_handle_t *zhp, const char *fromsnap, const char *tosnap,
}

err = gather_nvlist(zhp->zfs_hdl, zhp->zfs_name,
fromsnap, tosnap, flags->replicate, &fss, &fsavl);
fromsnap, tosnap, flags->replicate, flags->verbose,
&fss, &fsavl);
if (err)
goto err_out;
VERIFY(0 == nvlist_add_nvlist(hdrnv, "fss", fss));
Expand Down Expand Up @@ -2299,7 +2401,7 @@ recv_incremental_replication(libzfs_handle_t *hdl, const char *tofs,
needagain = progress = B_FALSE;

if ((error = gather_nvlist(hdl, tofs, fromsnap, NULL,
recursive, &local_nv, &local_avl)) != 0)
recursive, B_FALSE, &local_nv, &local_avl)) != 0)
return (error);

/*
Expand Down Expand Up @@ -3330,7 +3432,7 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
*/
*cp = '\0';
if (gather_nvlist(hdl, zc.zc_value, NULL, NULL, B_FALSE,
&local_nv, &local_avl) == 0) {
B_FALSE, &local_nv, &local_avl) == 0) {
*cp = '@';
fs = fsavl_find(local_avl, drrb->drr_toguid, NULL);
fsavl_destroy(local_avl);
Expand Down

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