Rescan enclosure sysfs path on import

When you create a pool, zfs writes vd->vdev_enc_sysfs_path with the
enclosure sysfs path to the fault LEDs, like:

  vdev_enc_sysfs_path = /sys/class/enclosure/0:0:1:0/SLOT8

However, this enclosure path doesn't get updated on successive imports
even if enclosure path to the disk changes.  This patch fixes the issue.

The largest part of this patch is moving for_each_vdev_vdev() and
associated function from zpool_iter.c to libzfs_internal.  This was
needed to make those functions visible to the cache import codepath for
sysfs path re-scan.  libzfs_internal is for code that is used by both
the libraries and the cmd/ code, but that we don't want to export with
the ABI.

Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Fixes: #11950

cmd/zpool/Makefile.am

@@ -26,7 +26,8 @@ zpool_LDADD = \
 	$(abs_top_builddir)/lib/libzfs/libzfs.la \
 	$(abs_top_builddir)/lib/libzfs_core/libzfs_core.la \
 	$(abs_top_builddir)/lib/libnvpair/libnvpair.la \
-	$(abs_top_builddir)/lib/libuutil/libuutil.la
+	$(abs_top_builddir)/lib/libuutil/libuutil.la \
+	$(abs_top_builddir)/lib/libzfs_internal/libzfs_internal.la
 
 zpool_LDADD += $(LTLIBINTL)
 

cmd/zpool/zpool_iter.c

@@ -37,6 +37,7 @@
 
 #include <libzfs.h>
 #include <libzutil.h>
+#include <libzfs_internal.h>
 #include <sys/zfs_context.h>
 #include <sys/wait.h>
 
@@ -264,72 +265,6 @@ for_each_pool(int argc, char **argv, boolean_t unavail,
 	return (ret);
 }
 
-static int
-for_each_vdev_cb(zpool_handle_t *zhp, nvlist_t *nv, pool_vdev_iter_f func,
-    void *data)
-{
-	nvlist_t **child;
-	uint_t c, children;
-	int ret = 0;
-	int i;
-	char *type;
-
-	const char *list[] = {
-	    ZPOOL_CONFIG_SPARES,
-	    ZPOOL_CONFIG_L2CACHE,
-	    ZPOOL_CONFIG_CHILDREN
-	};
-
-	for (i = 0; i < ARRAY_SIZE(list); i++) {
-		if (nvlist_lookup_nvlist_array(nv, list[i], &child,
-		    &children) == 0) {
-			for (c = 0; c < children; c++) {
-				uint64_t ishole = 0;
-
-				(void) nvlist_lookup_uint64(child[c],
-				    ZPOOL_CONFIG_IS_HOLE, &ishole);
-
-				if (ishole)
-					continue;
-
-				ret |= for_each_vdev_cb(zhp, child[c], func,
-				    data);
-			}
-		}
-	}
-
-	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) != 0)
-		return (ret);
-
-	/* Don't run our function on root vdevs */
-	if (strcmp(type, VDEV_TYPE_ROOT) != 0) {
-		ret |= func(zhp, nv, data);
-	}
-
-	return (ret);
-}
-
-/*
- * This is the equivalent of for_each_pool() for vdevs.  It iterates thorough
- * all vdevs in the pool, ignoring root vdevs and holes, calling func() on
- * each one.
- *
- * @zhp:	Zpool handle
- * @func:	Function to call on each vdev
- * @data:	Custom data to pass to the function
- */
-int
-for_each_vdev(zpool_handle_t *zhp, pool_vdev_iter_f func, void *data)
-{
-	nvlist_t *config, *nvroot = NULL;
-
-	if ((config = zpool_get_config(zhp, NULL)) != NULL) {
-		verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
-		    &nvroot) == 0);
-	}
-	return (for_each_vdev_cb(zhp, nvroot, func, data));
-}
-
 /*
  * Process the vcdl->vdev_cmd_data[] array to figure out all the unique column
  * names and their widths.  When this function is done, vcdl->uniq_cols,

cmd/zpool/zpool_main.c

@@ -70,6 +70,7 @@
 
 #include <libzfs.h>
 #include <libzutil.h>
+#include <libzfs_internal.h>
 
 #include "zpool_util.h"
 #include "zfs_comutil.h"

cmd/zpool/zpool_util.h

@@ -67,10 +67,6 @@ nvlist_t *split_mirror_vdev(zpool_handle_t *zhp, char *newname,
 int for_each_pool(int, char **, boolean_t unavail, zprop_list_t **,
     boolean_t, zpool_iter_f, void *);
 
-/* Vdev list functions */
-typedef int (*pool_vdev_iter_f)(zpool_handle_t *, nvlist_t *, void *);
-int for_each_vdev(zpool_handle_t *zhp, pool_vdev_iter_f func, void *data);
-
 typedef struct zpool_list zpool_list_t;
 
 zpool_list_t *pool_list_get(int, char **, zprop_list_t **, boolean_t, int *);

configure.ac

@@ -170,6 +170,7 @@ AC_CONFIG_FILES([
 	lib/libzpool/Makefile
 	lib/libzstd/Makefile
 	lib/libzutil/Makefile
+	lib/libzfs_internal/Makefile
 	man/Makefile
 	module/Kbuild
 	module/Makefile

include/Makefile.am

@@ -7,7 +7,8 @@ COMMON_H = \
 	zfs_deleg.h \
 	zfs_fletcher.h \
 	zfs_namecheck.h \
-	zfs_prop.h
+	zfs_prop.h \
+	libzfs_internal.h
 
 USER_H = \
 	libnvpair.h \

include/libzfs_internal.h

@@ -0,0 +1,17 @@
+#ifndef	_LIBZUTIL_INTERNAL
+#define	_LIBZUTIL_INTERNAL
+
+#include <libzfs.h>
+
+/* Vdev list functions */
+typedef int (*pool_vdev_iter_f)(zpool_handle_t *, nvlist_t *, void *);
+extern int for_each_vdev(zpool_handle_t *zhp, pool_vdev_iter_f func,
+    void *data);
+extern int for_each_vdev_in_nvlist(nvlist_t *nvroot, pool_vdev_iter_f func,
+    void *data);
+
+/* Only used by libzfs_config.c */
+nvlist_t *
+zpool_get_config_impl(zpool_handle_t *zhp, nvlist_t **oldconfig);
+
+#endif

include/libzutil.h

@@ -84,7 +84,8 @@ struct udev_device;
 _LIBZUTIL_H int zfs_device_get_devid(struct udev_device *, char *, size_t);
 _LIBZUTIL_H int zfs_device_get_physical(struct udev_device *, char *, size_t);
 
-_LIBZUTIL_H void update_vdev_config_dev_strs(nvlist_t *);
+_LIBZUTIL_H void update_vdev_config_dev_strs(nvlist_t *nv);
+void update_vdevs_config_dev_sysfs_path(nvlist_t *config);
 
 /*
  * Default device paths

lib/Makefile.am

@@ -14,7 +14,7 @@ endif
 SUBDIRS += libnvpair
 
 # libzutil depends on libefi if present
-SUBDIRS += libzutil libunicode
+SUBDIRS += libzfs_internal libzutil libunicode
 
 # These five libraries, which are installed as the final build product,
 # incorporate the eight convenience libraries given above.

lib/libzfs/Makefile.am

@@ -75,7 +75,8 @@ libzfs_la_LIBADD = \
 	$(abs_top_builddir)/lib/libshare/libshare.la \
 	$(abs_top_builddir)/lib/libzfs_core/libzfs_core.la \
 	$(abs_top_builddir)/lib/libnvpair/libnvpair.la \
-	$(abs_top_builddir)/lib/libuutil/libuutil.la
+	$(abs_top_builddir)/lib/libuutil/libuutil.la \
+	$(abs_top_builddir)/lib/libzfs_internal/libzfs_internal.la
 
 libzfs_la_LIBADD += -lm $(LIBCRYPTO_LIBS) $(ZLIB_LIBS) $(LIBFETCH_LIBS) $(LTLIBINTL)
 

lib/libzfs/libzfs_config.c

@@ -47,6 +47,7 @@
 #include <unistd.h>
 #include <libintl.h>
 #include <libuutil.h>
+#include <libzfs_internal.h>
 
 #include "libzfs_impl.h"
 
@@ -219,9 +220,7 @@ namespace_reload(libzfs_handle_t *hdl)
 nvlist_t *
 zpool_get_config(zpool_handle_t *zhp, nvlist_t **oldconfig)
 {
-	if (oldconfig)
-		*oldconfig = zhp->zpool_old_config;
-	return (zhp->zpool_config);
+	return (zpool_get_config_impl(zhp, oldconfig));
 }
 
 /*

lib/libzfs_internal/Makefile.am

@@ -0,0 +1,18 @@
+#
+# libzfs_internal is library that contains functions that are common to both
+# userspace code (like zpool_main.c) and to the libraries themselves, but
+# are not exported as in the ABI.
+#
+include $(top_srcdir)/config/Rules.am
+
+DEFAULT_INCLUDES += -I$(srcdir) -I$(top_srcdir)/lib/libzfs
+
+lib_LTLIBRARIES = libzfs_internal.la
+
+dist_libzfs_internal_la_SOURCES = \
+	libzfs_internal.c
+
+libzfs_internal_la_LIBADD = \
+	$(abs_top_builddir)/lib/libnvpair/libnvpair.la
+
+include $(top_srcdir)/config/CppCheck.am

lib/libzfs_internal/libzfs_internal.c

@@ -0,0 +1,100 @@
+#include <sys/fs/zfs.h>
+#include <libzutil.h>
+#include <libzfs.h>
+#include <libzfs_impl.h>
+#include <libzfs_internal.h>
+
+/*
+ * We want to call zpool_get_config() in this file, but that requires linking
+ * against libzfs... which requires this file as a dependency.  We can't
+ * just move zpool_get_config() to this file, since zpool_get_config() is part
+ * of the ABI, and wouldn't get exposed here.
+ *
+ * To get around this, we add the zpool_get_config_impl() dummy function which
+ * we can call directly in this file, and then update zpool_get_config() to
+ * call zpool_get_config_impl().
+ */
+nvlist_t *
+zpool_get_config_impl(zpool_handle_t *zhp, nvlist_t **oldconfig)
+{
+	if (oldconfig)
+		*oldconfig = zhp->zpool_old_config;
+	return (zhp->zpool_config);
+}
+
+static int
+for_each_vdev_cb(zpool_handle_t *zhp, nvlist_t *nv, pool_vdev_iter_f func,
+    void *data)
+{
+	nvlist_t **child;
+	uint_t c, children;
+	int ret = 0;
+	int i;
+	char *type;
+
+	const char *list[] = {
+	    ZPOOL_CONFIG_SPARES,
+	    ZPOOL_CONFIG_L2CACHE,
+	    ZPOOL_CONFIG_CHILDREN
+	};
+
+	for (i = 0; i < ARRAY_SIZE(list); i++) {
+		if (nvlist_lookup_nvlist_array(nv, list[i], &child,
+		    &children) == 0) {
+			for (c = 0; c < children; c++) {
+				uint64_t ishole = 0;
+
+				(void) nvlist_lookup_uint64(child[c],
+				    ZPOOL_CONFIG_IS_HOLE, &ishole);
+
+				if (ishole)
+					continue;
+
+				ret |= for_each_vdev_cb(zhp, child[c], func,
+				    data);
+			}
+		}
+	}
+
+	if (nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) != 0)
+		return (ret);
+
+	/* Don't run our function on root vdevs */
+	if (strcmp(type, VDEV_TYPE_ROOT) != 0) {
+		ret |= func(zhp, nv, data);
+	}
+
+	return (ret);
+}
+
+/*
+ * This is the equivalent of for_each_pool() for vdevs.  It iterates through
+ * all vdevs in the pool, ignoring root vdevs and holes, calling func() on
+ * each one.
+ *
+ * @zhp:	Zpool handle
+ * @func:	Function to call on each vdev
+ * @data:	Custom data to pass to the function
+ */
+int
+for_each_vdev(zpool_handle_t *zhp, pool_vdev_iter_f func, void *data)
+{
+	nvlist_t *config, *nvroot = NULL;
+
+	if ((config = zpool_get_config_impl(zhp, NULL)) != NULL) {
+		verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
+		    &nvroot) == 0);
+	}
+	return (for_each_vdev_cb(zhp, nvroot, func, data));
+}
+
+/*
+ * Given an ZPOOL_CONFIG_VDEV_TREE nvpair, iterate over all the vdevs, calling
+ * func() for each one.  func() is passed the vdev's nvlist and an optional
+ * user-defined 'data' pointer.
+ */
+int
+for_each_vdev_in_nvlist(nvlist_t *nvroot, pool_vdev_iter_f func, void *data)
+{
+	return (for_each_vdev_cb(NULL, nvroot, func, data));
+}

lib/libzutil/Makefile.am

@@ -42,7 +42,8 @@ libzutil_la_LIBADD = \
 	$(abs_top_builddir)/lib/libavl/libavl.la \
 	$(abs_top_builddir)/lib/libtpool/libtpool.la \
 	$(abs_top_builddir)/lib/libnvpair/libnvpair.la \
-	$(abs_top_builddir)/lib/libspl/libspl.la
+	$(abs_top_builddir)/lib/libspl/libspl.la \
+	$(abs_top_builddir)/lib/libzfs_internal/libzfs_internal.la
 
 if BUILD_LINUX
 libzutil_la_LIBADD += \

lib/libzutil/os/freebsd/zutil_import_os.c

@@ -247,3 +247,8 @@ zfs_dev_flush(int fd __unused)
 {
 	return (0);
 }
+
+void
+update_vdevs_config_dev_sysfs_path(nvlist_t *config)
+{
+}