/* * 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 https://opensource.org/licenses/CDDL-1.0. * 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 2010 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. * * Portions Copyright 2007 Ramprakash Jelari * Copyright (c) 2014, 2020 by Delphix. All rights reserved. * Copyright 2016 Igor Kozhukhov * Copyright (c) 2018 Datto Inc. */ #include #include #include #include #include #include #include #include #include "libzfs_impl.h" /* * Structure to keep track of dataset state. Before changing the 'sharenfs' or * 'mountpoint' property, we record whether the filesystem was previously * mounted/shared. This prior state dictates whether we remount/reshare the * dataset after the property has been changed. * * The interface consists of the following sequence of functions: * * changelist_gather() * changelist_prefix() * < change property > * changelist_postfix() * changelist_free() * * Other interfaces: * * changelist_remove() - remove a node from a gathered list * changelist_rename() - renames all datasets appropriately when doing a rename * changelist_unshare() - unshares all the nodes in a given changelist * changelist_haszonedchild() - check if there is any child exported to * a local zone */ typedef struct prop_changenode { zfs_handle_t *cn_handle; int cn_shared; int cn_mounted; int cn_zoned; boolean_t cn_needpost; /* is postfix() needed? */ uu_avl_node_t cn_treenode; } prop_changenode_t; struct prop_changelist { zfs_prop_t cl_prop; zfs_prop_t cl_realprop; zfs_prop_t cl_shareprop; /* used with sharenfs/sharesmb */ uu_avl_pool_t *cl_pool; uu_avl_t *cl_tree; boolean_t cl_waslegacy; boolean_t cl_allchildren; boolean_t cl_alldependents; int cl_mflags; /* Mount flags */ int cl_gflags; /* Gather request flags */ boolean_t cl_haszonedchild; }; /* * If the property is 'mountpoint', go through and unmount filesystems as * necessary. We don't do the same for 'sharenfs', because we can just re-share * with different options without interrupting service. We do handle 'sharesmb' * since there may be old resource names that need to be removed. */ int changelist_prefix(prop_changelist_t *clp) { prop_changenode_t *cn; uu_avl_walk_t *walk; int ret = 0; const enum sa_protocol smb[] = {SA_PROTOCOL_SMB, SA_NO_PROTOCOL}; boolean_t commit_smb_shares = B_FALSE; if (clp->cl_prop != ZFS_PROP_MOUNTPOINT && clp->cl_prop != ZFS_PROP_SHARESMB) return (0); if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_ROBUST)) == NULL) return (-1); while ((cn = uu_avl_walk_next(walk)) != NULL) { /* if a previous loop failed, set the remaining to false */ if (ret == -1) { cn->cn_needpost = B_FALSE; continue; } /* * If we are in the global zone, but this dataset is exported * to a local zone, do nothing. */ if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned) continue; if (!ZFS_IS_VOLUME(cn->cn_handle)) { /* * Do the property specific processing. */ switch (clp->cl_prop) { case ZFS_PROP_MOUNTPOINT: if (clp->cl_gflags & CL_GATHER_DONT_UNMOUNT) break; if (zfs_unmount(cn->cn_handle, NULL, clp->cl_mflags) != 0) { ret = -1; cn->cn_needpost = B_FALSE; } break; case ZFS_PROP_SHARESMB: (void) zfs_unshare(cn->cn_handle, NULL, smb); commit_smb_shares = B_TRUE; break; default: break; } } } if (commit_smb_shares) zfs_commit_shares(smb); uu_avl_walk_end(walk); if (ret == -1) (void) changelist_postfix(clp); return (ret); } /* * If the property is 'mountpoint' or 'sharenfs', go through and remount and/or * reshare the filesystems as necessary. In changelist_gather() we recorded * whether the filesystem was previously shared or mounted. The action we take * depends on the previous state, and whether the value was previously 'legacy'. * For non-legacy properties, we only remount/reshare the filesystem if it was * previously mounted/shared. Otherwise, we always remount/reshare the * filesystem. */ int changelist_postfix(prop_changelist_t *clp) { prop_changenode_t *cn; uu_avl_walk_t *walk; char shareopts[ZFS_MAXPROPLEN]; boolean_t commit_smb_shares = B_FALSE; boolean_t commit_nfs_shares = B_FALSE; /* * If we're changing the mountpoint, attempt to destroy the underlying * mountpoint. All other datasets will have inherited from this dataset * (in which case their mountpoints exist in the filesystem in the new * location), or have explicit mountpoints set (in which case they won't * be in the changelist). */ if ((cn = uu_avl_last(clp->cl_tree)) == NULL) return (0); if (clp->cl_prop == ZFS_PROP_MOUNTPOINT && !(clp->cl_gflags & CL_GATHER_DONT_UNMOUNT)) remove_mountpoint(cn->cn_handle); /* * We walk the datasets in reverse, because we want to mount any parent * datasets before mounting the children. We walk all datasets even if * there are errors. */ if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_REVERSE | UU_WALK_ROBUST)) == NULL) return (-1); while ((cn = uu_avl_walk_next(walk)) != NULL) { boolean_t sharenfs; boolean_t sharesmb; boolean_t mounted; boolean_t needs_key; /* * If we are in the global zone, but this dataset is exported * to a local zone, do nothing. */ if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned) continue; /* Only do post-processing if it's required */ if (!cn->cn_needpost) continue; cn->cn_needpost = B_FALSE; zfs_refresh_properties(cn->cn_handle); if (ZFS_IS_VOLUME(cn->cn_handle)) continue; /* * Remount if previously mounted or mountpoint was legacy, * or sharenfs or sharesmb property is set. */ sharenfs = ((zfs_prop_get(cn->cn_handle, ZFS_PROP_SHARENFS, shareopts, sizeof (shareopts), NULL, NULL, 0, B_FALSE) == 0) && (strcmp(shareopts, "off") != 0)); sharesmb = ((zfs_prop_get(cn->cn_handle, ZFS_PROP_SHARESMB, shareopts, sizeof (shareopts), NULL, NULL, 0, B_FALSE) == 0) && (strcmp(shareopts, "off") != 0)); needs_key = (zfs_prop_get_int(cn->cn_handle, ZFS_PROP_KEYSTATUS) == ZFS_KEYSTATUS_UNAVAILABLE); mounted = (clp->cl_gflags & CL_GATHER_DONT_UNMOUNT) || zfs_is_mounted(cn->cn_handle, NULL); if (!mounted && !needs_key && (cn->cn_mounted || (((clp->cl_prop == ZFS_PROP_MOUNTPOINT && clp->cl_prop == clp->cl_realprop) || sharenfs || sharesmb || clp->cl_waslegacy) && (zfs_prop_get_int(cn->cn_handle, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_ON)))) { if (zfs_mount(cn->cn_handle, NULL, 0) == 0) mounted = TRUE; } /* * If the file system is mounted we always re-share even * if the filesystem is currently shared, so that we can * adopt any new options. */ const enum sa_protocol nfs[] = {SA_PROTOCOL_NFS, SA_NO_PROTOCOL}; if (sharenfs && mounted) { zfs_share(cn->cn_handle, nfs); commit_nfs_shares = B_TRUE; } else if (cn->cn_shared || clp->cl_waslegacy) { zfs_unshare(cn->cn_handle, NULL, nfs); commit_nfs_shares = B_TRUE; } const enum sa_protocol smb[] = {SA_PROTOCOL_SMB, SA_NO_PROTOCOL}; if (sharesmb && mounted) { zfs_share(cn->cn_handle, smb); commit_smb_shares = B_TRUE; } else if (cn->cn_shared || clp->cl_waslegacy) { zfs_unshare(cn->cn_handle, NULL, smb); commit_smb_shares = B_TRUE; } } enum sa_protocol proto[SA_PROTOCOL_COUNT + 1], *p = proto; if (commit_nfs_shares) *p++ = SA_PROTOCOL_NFS; if (commit_smb_shares) *p++ = SA_PROTOCOL_SMB; *p++ = SA_NO_PROTOCOL; zfs_commit_shares(proto); uu_avl_walk_end(walk); return (0); } /* * Is this "dataset" a child of "parent"? */ static boolean_t isa_child_of(const char *dataset, const char *parent) { int len; len = strlen(parent); if (strncmp(dataset, parent, len) == 0 && (dataset[len] == '@' || dataset[len] == '/' || dataset[len] == '\0')) return (B_TRUE); else return (B_FALSE); } /* * If we rename a filesystem, child filesystem handles are no longer valid * since we identify each dataset by its name in the ZFS namespace. As a * result, we have to go through and fix up all the names appropriately. We * could do this automatically if libzfs kept track of all open handles, but * this is a lot less work. */ void changelist_rename(prop_changelist_t *clp, const char *src, const char *dst) { prop_changenode_t *cn; uu_avl_walk_t *walk; char newname[ZFS_MAX_DATASET_NAME_LEN]; if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_ROBUST)) == NULL) return; while ((cn = uu_avl_walk_next(walk)) != NULL) { /* * Do not rename a clone that's not in the source hierarchy. */ if (!isa_child_of(cn->cn_handle->zfs_name, src)) continue; /* * Destroy the previous mountpoint if needed. */ remove_mountpoint(cn->cn_handle); (void) strlcpy(newname, dst, sizeof (newname)); (void) strlcat(newname, cn->cn_handle->zfs_name + strlen(src), sizeof (newname)); (void) strlcpy(cn->cn_handle->zfs_name, newname, sizeof (cn->cn_handle->zfs_name)); } uu_avl_walk_end(walk); } /* * Given a gathered changelist for the 'sharenfs' or 'sharesmb' property, * unshare all the datasets in the list. */ int changelist_unshare(prop_changelist_t *clp, const enum sa_protocol *proto) { prop_changenode_t *cn; uu_avl_walk_t *walk; int ret = 0; if (clp->cl_prop != ZFS_PROP_SHARENFS && clp->cl_prop != ZFS_PROP_SHARESMB) return (0); if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_ROBUST)) == NULL) return (-1); while ((cn = uu_avl_walk_next(walk)) != NULL) { if (zfs_unshare(cn->cn_handle, NULL, proto) != 0) ret = -1; } for (const enum sa_protocol *p = proto; *p != SA_NO_PROTOCOL; ++p) sa_commit_shares(*p); uu_avl_walk_end(walk); return (ret); } /* * Check if there is any child exported to a local zone in a given changelist. * This information has already been recorded while gathering the changelist * via changelist_gather(). */ int changelist_haszonedchild(prop_changelist_t *clp) { return (clp->cl_haszonedchild); } /* * Remove a node from a gathered list. */ void changelist_remove(prop_changelist_t *clp, const char *name) { prop_changenode_t *cn; uu_avl_walk_t *walk; if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_ROBUST)) == NULL) return; while ((cn = uu_avl_walk_next(walk)) != NULL) { if (strcmp(cn->cn_handle->zfs_name, name) == 0) { uu_avl_remove(clp->cl_tree, cn); zfs_close(cn->cn_handle); free(cn); uu_avl_walk_end(walk); return; } } uu_avl_walk_end(walk); } /* * Release any memory associated with a changelist. */ void changelist_free(prop_changelist_t *clp) { prop_changenode_t *cn; if (clp->cl_tree) { uu_avl_walk_t *walk; if ((walk = uu_avl_walk_start(clp->cl_tree, UU_WALK_ROBUST)) == NULL) return; while ((cn = uu_avl_walk_next(walk)) != NULL) { uu_avl_remove(clp->cl_tree, cn); zfs_close(cn->cn_handle); free(cn); } uu_avl_walk_end(walk); uu_avl_destroy(clp->cl_tree); } if (clp->cl_pool) uu_avl_pool_destroy(clp->cl_pool); free(clp); } /* * Add one dataset to changelist */ static int changelist_add_mounted(zfs_handle_t *zhp, void *data) { prop_changelist_t *clp = data; prop_changenode_t *cn; uu_avl_index_t idx; ASSERT3U(clp->cl_prop, ==, ZFS_PROP_MOUNTPOINT); cn = zfs_alloc(zfs_get_handle(zhp), sizeof (prop_changenode_t)); cn->cn_handle = zhp; cn->cn_mounted = zfs_is_mounted(zhp, NULL); ASSERT3U(cn->cn_mounted, ==, B_TRUE); cn->cn_shared = zfs_is_shared(zhp, NULL, NULL); cn->cn_zoned = zfs_prop_get_int(zhp, ZFS_PROP_ZONED); cn->cn_needpost = B_TRUE; /* Indicate if any child is exported to a local zone. */ if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned) clp->cl_haszonedchild = B_TRUE; uu_avl_node_init(cn, &cn->cn_treenode, clp->cl_pool); if (uu_avl_find(clp->cl_tree, cn, NULL, &idx) == NULL) { uu_avl_insert(clp->cl_tree, cn, idx); } else { free(cn); zfs_close(zhp); } return (0); } static int change_one(zfs_handle_t *zhp, void *data) { prop_changelist_t *clp = data; char property[ZFS_MAXPROPLEN]; char where[64]; prop_changenode_t *cn = NULL; zprop_source_t sourcetype = ZPROP_SRC_NONE; zprop_source_t share_sourcetype = ZPROP_SRC_NONE; int ret = 0; /* * We only want to unmount/unshare those filesystems that may inherit * from the target filesystem. If we find any filesystem with a * locally set mountpoint, we ignore any children since changing the * property will not affect them. If this is a rename, we iterate * over all children regardless, since we need them unmounted in * order to do the rename. Also, if this is a volume and we're doing * a rename, then always add it to the changelist. */ if (!(ZFS_IS_VOLUME(zhp) && clp->cl_realprop == ZFS_PROP_NAME) && zfs_prop_get(zhp, clp->cl_prop, property, sizeof (property), &sourcetype, where, sizeof (where), B_FALSE) != 0) { goto out; } /* * If we are "watching" sharenfs or sharesmb * then check out the companion property which is tracked * in cl_shareprop */ if (clp->cl_shareprop != ZPROP_INVAL && zfs_prop_get(zhp, clp->cl_shareprop, property, sizeof (property), &share_sourcetype, where, sizeof (where), B_FALSE) != 0) { goto out; } if (clp->cl_alldependents || clp->cl_allchildren || sourcetype == ZPROP_SRC_DEFAULT || sourcetype == ZPROP_SRC_INHERITED || (clp->cl_shareprop != ZPROP_INVAL && (share_sourcetype == ZPROP_SRC_DEFAULT || share_sourcetype == ZPROP_SRC_INHERITED))) { cn = zfs_alloc(zfs_get_handle(zhp), sizeof (prop_changenode_t)); cn->cn_handle = zhp; cn->cn_mounted = (clp->cl_gflags & CL_GATHER_MOUNT_ALWAYS) || zfs_is_mounted(zhp, NULL); cn->cn_shared = zfs_is_shared(zhp, NULL, NULL); cn->cn_zoned = zfs_prop_get_int(zhp, ZFS_PROP_ZONED); cn->cn_needpost = B_TRUE; /* Indicate if any child is exported to a local zone. */ if (getzoneid() == GLOBAL_ZONEID && cn->cn_zoned) clp->cl_haszonedchild = B_TRUE; uu_avl_node_init(cn, &cn->cn_treenode, clp->cl_pool); uu_avl_index_t idx; if (uu_avl_find(clp->cl_tree, cn, NULL, &idx) == NULL) { uu_avl_insert(clp->cl_tree, cn, idx); } else { free(cn); cn = NULL; } if (!clp->cl_alldependents) ret = zfs_iter_children_v2(zhp, 0, change_one, data); /* * If we added the handle to the changelist, we will re-use it * later so return without closing it. */ if (cn != NULL) return (ret); } out: zfs_close(zhp); return (ret); } static int compare_props(const void *a, const void *b, zfs_prop_t prop) { const prop_changenode_t *ca = a; const prop_changenode_t *cb = b; char propa[MAXPATHLEN]; char propb[MAXPATHLEN]; boolean_t haspropa, haspropb; haspropa = (zfs_prop_get(ca->cn_handle, prop, propa, sizeof (propa), NULL, NULL, 0, B_FALSE) == 0); haspropb = (zfs_prop_get(cb->cn_handle, prop, propb, sizeof (propb), NULL, NULL, 0, B_FALSE) == 0); if (!haspropa && haspropb) return (-1); else if (haspropa && !haspropb) return (1); else if (!haspropa && !haspropb) return (0); else return (strcmp(propb, propa)); } static int compare_mountpoints(const void *a, const void *b, void *unused) { /* * When unsharing or unmounting filesystems, we need to do it in * mountpoint order. This allows the user to have a mountpoint * hierarchy that is different from the dataset hierarchy, and still * allow it to be changed. */ (void) unused; return (compare_props(a, b, ZFS_PROP_MOUNTPOINT)); } static int compare_dataset_names(const void *a, const void *b, void *unused) { (void) unused; return (compare_props(a, b, ZFS_PROP_NAME)); } /* * Given a ZFS handle and a property, construct a complete list of datasets * that need to be modified as part of this process. For anything but the * 'mountpoint' and 'sharenfs' properties, this just returns an empty list. * Otherwise, we iterate over all children and look for any datasets that * inherit the property. For each such dataset, we add it to the list and * mark whether it was shared beforehand. */ prop_changelist_t * changelist_gather(zfs_handle_t *zhp, zfs_prop_t prop, int gather_flags, int mnt_flags) { prop_changelist_t *clp; prop_changenode_t *cn; zfs_handle_t *temp; char property[ZFS_MAXPROPLEN]; boolean_t legacy = B_FALSE; clp = zfs_alloc(zhp->zfs_hdl, sizeof (prop_changelist_t)); /* * For mountpoint-related tasks, we want to sort everything by * mountpoint, so that we mount and unmount them in the appropriate * order, regardless of their position in the hierarchy. */ if (prop == ZFS_PROP_NAME || prop == ZFS_PROP_ZONED || prop == ZFS_PROP_MOUNTPOINT || prop == ZFS_PROP_SHARENFS || prop == ZFS_PROP_SHARESMB) { if (zfs_prop_get(zhp, ZFS_PROP_MOUNTPOINT, property, sizeof (property), NULL, NULL, 0, B_FALSE) == 0 && (strcmp(property, "legacy") == 0 || strcmp(property, "none") == 0)) { legacy = B_TRUE; } } clp->cl_pool = uu_avl_pool_create("changelist_pool", sizeof (prop_changenode_t), offsetof(prop_changenode_t, cn_treenode), legacy ? compare_dataset_names : compare_mountpoints, 0); if (clp->cl_pool == NULL) { assert(uu_error() == UU_ERROR_NO_MEMORY); (void) zfs_error(zhp->zfs_hdl, EZFS_NOMEM, "internal error"); changelist_free(clp); return (NULL); } clp->cl_tree = uu_avl_create(clp->cl_pool, NULL, UU_DEFAULT); clp->cl_gflags = gather_flags; clp->cl_mflags = mnt_flags; if (clp->cl_tree == NULL) { assert(uu_error() == UU_ERROR_NO_MEMORY); (void) zfs_error(zhp->zfs_hdl, EZFS_NOMEM, "internal error"); changelist_free(clp); return (NULL); } /* * If this is a rename or the 'zoned' property, we pretend we're * changing the mountpoint and flag it so we can catch all children in * change_one(). * * Flag cl_alldependents to catch all children plus the dependents * (clones) that are not in the hierarchy. */ if (prop == ZFS_PROP_NAME) { clp->cl_prop = ZFS_PROP_MOUNTPOINT; clp->cl_alldependents = B_TRUE; } else if (prop == ZFS_PROP_ZONED) { clp->cl_prop = ZFS_PROP_MOUNTPOINT; clp->cl_allchildren = B_TRUE; } else if (prop == ZFS_PROP_CANMOUNT) { clp->cl_prop = ZFS_PROP_MOUNTPOINT; } else if (prop == ZFS_PROP_VOLSIZE) { clp->cl_prop = ZFS_PROP_MOUNTPOINT; } else { clp->cl_prop = prop; } clp->cl_realprop = prop; if (clp->cl_prop != ZFS_PROP_MOUNTPOINT && clp->cl_prop != ZFS_PROP_SHARENFS && clp->cl_prop != ZFS_PROP_SHARESMB) return (clp); /* * If watching SHARENFS or SHARESMB then * also watch its companion property. */ if (clp->cl_prop == ZFS_PROP_SHARENFS) clp->cl_shareprop = ZFS_PROP_SHARESMB; else if (clp->cl_prop == ZFS_PROP_SHARESMB) clp->cl_shareprop = ZFS_PROP_SHARENFS; if (clp->cl_prop == ZFS_PROP_MOUNTPOINT && (clp->cl_gflags & CL_GATHER_ITER_MOUNTED)) { /* * Instead of iterating through all of the dataset children we * gather mounted dataset children from MNTTAB */ if (zfs_iter_mounted(zhp, changelist_add_mounted, clp) != 0) { changelist_free(clp); return (NULL); } } else if (clp->cl_alldependents) { if (zfs_iter_dependents_v2(zhp, 0, B_TRUE, change_one, clp) != 0) { changelist_free(clp); return (NULL); } } else if (zfs_iter_children_v2(zhp, 0, change_one, clp) != 0) { changelist_free(clp); return (NULL); } /* * We have to re-open ourselves because we auto-close all the handles * and can't tell the difference. */ if ((temp = zfs_open(zhp->zfs_hdl, zfs_get_name(zhp), ZFS_TYPE_DATASET)) == NULL) { changelist_free(clp); return (NULL); } /* * Always add ourself to the list. We add ourselves to the end so that * we're the last to be unmounted. */ cn = zfs_alloc(zhp->zfs_hdl, sizeof (prop_changenode_t)); cn->cn_handle = temp; cn->cn_mounted = (clp->cl_gflags & CL_GATHER_MOUNT_ALWAYS) || zfs_is_mounted(temp, NULL); cn->cn_shared = zfs_is_shared(temp, NULL, NULL); cn->cn_zoned = zfs_prop_get_int(zhp, ZFS_PROP_ZONED); cn->cn_needpost = B_TRUE; uu_avl_node_init(cn, &cn->cn_treenode, clp->cl_pool); uu_avl_index_t idx; if (uu_avl_find(clp->cl_tree, cn, NULL, &idx) == NULL) { uu_avl_insert(clp->cl_tree, cn, idx); } else { free(cn); zfs_close(temp); } /* * If the mountpoint property was previously 'legacy', or 'none', * record it as the behavior of changelist_postfix() will be different. */ if ((clp->cl_prop == ZFS_PROP_MOUNTPOINT) && legacy) { /* * do not automatically mount ex-legacy datasets if * we specifically set canmount to noauto */ if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) != ZFS_CANMOUNT_NOAUTO) clp->cl_waslegacy = B_TRUE; } return (clp); }