svn commit: r356876 - head/cddl/contrib/opensolaris/lib/libzfs/common

[Kyle Evans]

Author: kevans
Date: Sun Jan 19 02:45:02 2020
New Revision: 356876
URL: https://svnweb.freebsd.org/changeset/base/356876

Log:
  libzfs: add zfs_mount_at
  
  This will be used in libbe in place of the internal zmount(); libbe only
  wants to be able to mount a dataset at an arbitrary mountpoint without
  altering dataset/pool properties. The natural way to do this in a portable
  way is by creating a zfs_mount_at() interface that's effectively zfs_mount()
  + a mountpoint parameter. zfs_mount() is now a light wrapper around the new
  method.
  
  The interface and implementation have already been accepted into ZFS On
  Linux, and the next commit to switch libbe() over to this new interface will
  solve the last compatibility issue with ZoL.  The next sysutils/openzfs
  rebase against ZoL should be able to build libbe/bectl with only minor
  adjustments to build glue.
  
  Reviewed by:	Ryan Moeller <ryan freqlabs com>
  MFC after:	3 days
  Differential Revision:	https://reviews.freebsd.org/D23132

Modified:
  head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
  head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_mount.c

Modified: head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
==============================================================================
--- head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h	Sat Jan 18 23:46:50 2020	(r356875)
+++ head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h	Sun Jan 19 02:45:02 2020	(r356876)
@@ -769,6 +769,7 @@ extern ulong_t get_system_hostid(void);
 extern boolean_t is_mounted(libzfs_handle_t *, const char *special, char **);
 extern boolean_t zfs_is_mounted(zfs_handle_t *, char **);
 extern int zfs_mount(zfs_handle_t *, const char *, int);
+extern int zfs_mount_at(zfs_handle_t *, const char *, int, const char *);
 extern int zfs_unmount(zfs_handle_t *, const char *, int);
 extern int zfs_unmountall(zfs_handle_t *, int);
 

Modified: head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_mount.c
==============================================================================
--- head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_mount.c	Sat Jan 18 23:46:50 2020	(r356875)
+++ head/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_mount.c	Sun Jan 19 02:45:02 2020	(r356876)
@@ -301,6 +301,17 @@ zfs_is_mounted(zfs_handle_t *zhp, char **where)
 	return (is_mounted(zhp->zfs_hdl, zfs_get_name(zhp), where));
 }
 
+static boolean_t
+zfs_is_mountable_internal(zfs_handle_t *zhp, const char *mountpoint)
+{
+
+	if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED) &&
+	    getzoneid() == GLOBAL_ZONEID)
+		return (B_FALSE);
+
+	return (B_TRUE);
+}
+
 /*
  * Returns true if the given dataset is mountable, false otherwise.  Returns the
  * mountpoint in 'buf'.
@@ -325,8 +336,7 @@ zfs_is_mountable(zfs_handle_t *zhp, char *buf, size_t 
 	if (zfs_prop_get_int(zhp, ZFS_PROP_CANMOUNT) == ZFS_CANMOUNT_OFF)
 		return (B_FALSE);
 
-	if (zfs_prop_get_int(zhp, ZFS_PROP_ZONED) &&
-	    getzoneid() == GLOBAL_ZONEID)
+	if (!zfs_is_mountable_internal(zhp, buf))
 		return (B_FALSE);
 
 	if (source)
@@ -341,8 +351,19 @@ zfs_is_mountable(zfs_handle_t *zhp, char *buf, size_t 
 int
 zfs_mount(zfs_handle_t *zhp, const char *options, int flags)
 {
-	struct stat buf;
 	char mountpoint[ZFS_MAXPROPLEN];
+
+	if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
+		return (0);
+
+	return (zfs_mount_at(zhp, options, flags, mountpoint));
+}
+
+int
+zfs_mount_at(zfs_handle_t *zhp, const char *options, int flags,
+    const char *mountpoint)
+{
+	struct stat buf;
 	char mntopts[MNT_LINE_MAX];
 	libzfs_handle_t *hdl = zhp->zfs_hdl;
 
@@ -357,8 +378,8 @@ zfs_mount(zfs_handle_t *zhp, const char *options, int 
 	if (zpool_get_prop_int(zhp->zpool_hdl, ZPOOL_PROP_READONLY, NULL))
 		flags |= MS_RDONLY;
 
-	if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
-		return (0);
+	if (!zfs_is_mountable_internal(zhp, mountpoint))
+		return (B_FALSE);
 
 	/* Create the directory if it doesn't already exist */
 	if (lstat(mountpoint, &buf) != 0) {