3 files changed, 102 insertions, 3 deletions

diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
index f2a9ebf..9133238 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs.h
@@ -774,6 +774,7 @@ extern int zpool_in_use(libzfs_handle_t *, int, pool_state_t *, char **,
  * Label manipulation.
  */
 extern int zpool_read_label(int, nvlist_t **);
+extern int zpool_read_all_labels(int, nvlist_t **);
 extern int zpool_clear_label(int);
 
 /* is this zvol valid for use as a dump device? */
diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
index 1bbb8c5..a8da5b4 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_import.c
@@ -42,6 +42,7 @@
  * using our derived config, and record the results.
  */
 
+#include <aio.h>
 #include <ctype.h>
 #include <devid.h>
 #include <dirent.h>
@@ -915,6 +916,90 @@ zpool_read_label(int fd, nvlist_t **config)
 	return (-1);
 }
 
+/*
+ * Given a file descriptor, read the label information and return an nvlist
+ * describing the configuration, if there is one.
+ * returns the number of valid labels found
+ * If a label is found, returns it via config.  The caller is responsible for
+ * freeing it.
+ */
+int
+zpool_read_all_labels(int fd, nvlist_t **config)
+{
+	struct stat64 statbuf;
+	struct aiocb aiocbs[VDEV_LABELS];
+	struct aiocb *aiocbps[VDEV_LABELS];
+	int l;
+	vdev_phys_t *labels;
+	uint64_t state, txg, size;
+	int nlabels = 0;
+
+	*config = NULL;
+
+	if (fstat64(fd, &statbuf) == -1)
+		return (0);
+	size = P2ALIGN_TYPED(statbuf.st_size, sizeof (vdev_label_t), uint64_t);
+
+	if ((labels = calloc(VDEV_LABELS, sizeof (vdev_phys_t))) == NULL)
+		return (0);
+
+	memset(aiocbs, 0, sizeof(aiocbs));
+	for (l = 0; l < VDEV_LABELS; l++) {
+		aiocbs[l].aio_fildes = fd;
+		aiocbs[l].aio_offset = label_offset(size, l) + VDEV_SKIP_SIZE;
+		aiocbs[l].aio_buf = &labels[l];
+		aiocbs[l].aio_nbytes = sizeof(vdev_phys_t);
+		aiocbs[l].aio_lio_opcode = LIO_READ;
+		aiocbps[l] = &aiocbs[l];
+	}
+
+	if (lio_listio(LIO_WAIT, aiocbps, VDEV_LABELS, NULL) != 0) {
+		if (errno == EAGAIN || errno == EINTR || errno == EIO) {
+			for (l = 0; l < VDEV_LABELS; l++) {
+				errno = 0;
+				int r = aio_error(&aiocbs[l]);
+				if (r != EINVAL)
+					(void)aio_return(&aiocbs[l]);
+			}
+		}
+		free(labels);
+		return (0);
+	}
+
+	for (l = 0; l < VDEV_LABELS; l++) {
+		nvlist_t *temp = NULL;
+
+		if (aio_return(&aiocbs[l]) != sizeof(vdev_phys_t))
+			continue;
+
+		if (nvlist_unpack(labels[l].vp_nvlist,
+		    sizeof (labels[l].vp_nvlist), &temp, 0) != 0)
+			continue;
+
+		if (nvlist_lookup_uint64(temp, ZPOOL_CONFIG_POOL_STATE,
+		    &state) != 0 || state > POOL_STATE_L2CACHE) {
+			nvlist_free(temp);
+			temp = NULL;
+			continue;
+		}
+
+		if (state != POOL_STATE_SPARE && state != POOL_STATE_L2CACHE &&
+		    (nvlist_lookup_uint64(temp, ZPOOL_CONFIG_POOL_TXG,
+		    &txg) != 0 || txg == 0)) {
+			nvlist_free(temp);
+			temp = NULL;
+			continue;
+		}
+		if (temp)
+			*config = temp;
+
+		nlabels++;
+	}
+
+	free(labels);
+	return (nlabels);
+}
+
 typedef struct rdsk_node {
 	char *rn_name;
 	int rn_dfd;
diff --git a/cddl/usr.sbin/zfsd/zfsd_event.cc b/cddl/usr.sbin/zfsd/zfsd_event.cc
index c10cc18..5594b35 100644
--- a/cddl/usr.sbin/zfsd/zfsd_event.cc
+++ b/cddl/usr.sbin/zfsd/zfsd_event.cc
@@ -36,6 +36,7 @@
 #include <sys/cdefs.h>
 #include <sys/time.h>
 #include <sys/fs/zfs.h>
+#include <sys/vdev_impl.h>
 
 #include <syslog.h>
 
@@ -93,21 +94,32 @@ DevfsEvent::ReadLabel(int devFd, bool &inUse, bool &degraded)
 	pool_state_t poolState;
 	char        *poolName;
 	boolean_t    b_inuse;
+	int          nlabels;
 
 	inUse    = false;
 	degraded = false;
 	poolName = NULL;
 	if (zpool_in_use(g_zfsHandle, devFd, &poolState,
 			 &poolName, &b_inuse) == 0) {
-		nvlist_t *devLabel;
+		nvlist_t *devLabel = NULL;
 
 		inUse = b_inuse == B_TRUE;
 		if (poolName != NULL)
 			free(poolName);
 
-		if (zpool_read_label(devFd, &devLabel) != 0
-		 || devLabel == NULL)
+		nlabels = zpool_read_all_labels(devFd, &devLabel);
+		/*
+		 * If we find a disk with fewer than the maximum number of
+		 * labels, it might be the whole disk of a partitioned disk
+		 * where ZFS resides on a partition.  In that case, we should do
+		 * nothing and wait for the partition to appear.  Or, the disk
+		 * might be damaged.  In that case, zfsd should do nothing and
+		 * wait for the sysadmin to decide.
+		 */
+		if (nlabels != VDEV_LABELS || devLabel == NULL) {
+			nvlist_free(devLabel);
 			return (NULL);
+		}
 
 		try {
 			Vdev vdev(devLabel);
@@ -121,6 +133,7 @@ DevfsEvent::ReadLabel(int devFd, bool &inUse, bool &degraded)
 
 			exp.GetString().insert(0, context);
 			exp.Log();
+			nvlist_free(devLabel);
 		}
 	}
 	return (NULL);