MFV r274273:

ZFS large block support.

Please note that booting from datasets that have recordsize greater
than 128KB is not supported (but it's Okay to enable the feature on
the pool).  This *may* remain unchanged because of memory constraint.

Limited safety belt is provided for mounted root filesystem but use
caution is advised.

Illumos issue:
    5027 zfs large block support

MFC after:	1 month

1 files changed, 27 insertions, 12 deletions

diff --git a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
index 265038ab1bf9..063df4a3c234 100644
--- a/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
+++ b/cddl/contrib/opensolaris/lib/libzfs/common/libzfs_dataset.c
@@ -1080,21 +1080,36 @@ zfs_valid_proplist(libzfs_handle_t *hdl, zfs_type_t type, nvlist_t *nvl,
 			break;
 		}
 
-		case ZFS_PROP_RECORDSIZE:
 		case ZFS_PROP_VOLBLOCKSIZE:
-			/* must be power of two within SPA_{MIN,MAX}BLOCKSIZE */
+		case ZFS_PROP_RECORDSIZE:
+		{
+			int maxbs = SPA_MAXBLOCKSIZE;
+			if (zhp != NULL) {
+				maxbs = zpool_get_prop_int(zhp->zpool_hdl,
+				    ZPOOL_PROP_MAXBLOCKSIZE, NULL);
+			}
+			/*
+			 * Volumes are limited to a volblocksize of 128KB,
+			 * because they typically service workloads with
+			 * small random writes, which incur a large performance
+			 * penalty with large blocks.
+			 */
+			if (prop == ZFS_PROP_VOLBLOCKSIZE)
+				maxbs = SPA_OLD_MAXBLOCKSIZE;
+			/*
+			 * The value must be a power of two between
+			 * SPA_MINBLOCKSIZE and maxbs.
+			 */
 			if (intval < SPA_MINBLOCKSIZE ||
-			    intval > SPA_MAXBLOCKSIZE || !ISP2(intval)) {
+			    intval > maxbs || !ISP2(intval)) {
 				zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
-				    "'%s' must be power of 2 from %u "
-				    "to %uk"), propname,
-				    (uint_t)SPA_MINBLOCKSIZE,
-				    (uint_t)SPA_MAXBLOCKSIZE >> 10);
+				    "'%s' must be power of 2 from 512B "
+				    "to %uKB"), propname, maxbs >> 10);
 				(void) zfs_error(hdl, EZFS_BADPROP, errbuf);
 				goto error;
 			}
 			break;
-
+		}
 		case ZFS_PROP_MLSLABEL:
 		{
 #ifdef sun
@@ -1471,7 +1486,9 @@ zfs_setprop_error(libzfs_handle_t *hdl, zfs_prop_t prop, int err,
 		break;
 
 	case ERANGE:
-		if (prop == ZFS_PROP_COMPRESSION) {
+	case EDOM:
+		if (prop == ZFS_PROP_COMPRESSION ||
+		    prop == ZFS_PROP_RECORDSIZE) {
 			(void) zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 			    "property setting is not allowed on "
 			    "bootable datasets"));
@@ -3197,9 +3214,7 @@ zfs_create(libzfs_handle_t *hdl, const char *path, zfs_type_t type,
 		case EDOM:
 			zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 			    "volume block size must be power of 2 from "
-			    "%u to %uk"),
-			    (uint_t)SPA_MINBLOCKSIZE,
-			    (uint_t)SPA_MAXBLOCKSIZE >> 10);
+			    "512B to 128KB"));
 
 			return (zfs_error(hdl, EZFS_BADPROP, errbuf));