Increase allowed 'special_small_blocks' maximum value

There may be circumstances where it's desirable that all blocks in a specified dataset be stored on the special device. Relax the artificial 128K limit and allow the special_small_blocks property to be set up to 1M. When blocks >1MB have been enabled via the zfs_max_recordsize module option, this limit is increased accordingly. Signed-off-by: Brian Behlendorf <[email protected]> Issue #9131
openzfs · Nov 11, 2019 · 254d15a · 254d15a
1 parent 035ebb3
commit 254d15a
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Showing 2 changed files with 15 additions and 5 deletions.
diff --git a/lib/libzfs/libzfs_dataset.c b/lib/libzfs/libzfs_dataset.c
@@ -1231,12 +1231,19 @@ zfs_valid_proplist(libzfs_handle_t *hdl, zfs_type_t type, nvlist_t *nvl,
 		}
 
 		case ZFS_PROP_SPECIAL_SMALL_BLOCKS:
+		{
+			int maxbs = SPA_OLD_MAXBLOCKSIZE;
+			char buf[64];
+
 			if (zpool_hdl != NULL) {
 				char state[64] = "";
 
+				maxbs = zpool_get_prop_int(zpool_hdl,
+				    ZPOOL_PROP_MAXBLOCKSIZE, NULL);
+
 				/*
 				 * Issue a warning but do not fail so that
-				 * tests for setable properties succeed.
+				 * tests for settable properties succeed.
 				 */
 				if (zpool_prop_get_feature(zpool_hdl,
 				    "feature@allocation_classes", state,
@@ -1249,15 +1256,17 @@ zfs_valid_proplist(libzfs_handle_t *hdl, zfs_type_t type, nvlist_t *nvl,
 			}
 			if (intval != 0 &&
 			    (intval < SPA_MINBLOCKSIZE ||
-			    intval > SPA_OLD_MAXBLOCKSIZE || !ISP2(intval))) {
+			    intval > maxbs || !ISP2(intval))) {
+				zfs_nicebytes(maxbs, buf, sizeof (buf));
 				zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 				    "invalid '%s=%d' property: must be zero or "
-				    "a power of 2 from 512B to 128K"), propname,
-				    intval);
+				    "a power of 2 from 512B to %s"), propname,
+				    intval, buf);
 				(void) zfs_error(hdl, EZFS_BADPROP, errbuf);
 				goto error;
 			}
 			break;
+		}
 
 		case ZFS_PROP_MLSLABEL:
 		{

diff --git a/tests/zfs-tests/tests/functional/alloc_class/alloc_class_011_neg.ksh b/tests/zfs-tests/tests/functional/alloc_class/alloc_class_011_neg.ksh
@@ -21,6 +21,7 @@
 #
 # DESCRIPTION:
 #	Setting the special_small_blocks property to invalid values fails.
+#	Powers of two from 512 to 1M are allowed.
 #
 
 verify_runnable "global"
@@ -34,7 +35,7 @@ log_must disk_setup
 log_must zpool create $TESTPOOL raidz $ZPOOL_DISKS special mirror \
 	$CLASS_DISK0 $CLASS_DISK1
 
-for value in 256 1025 262144
+for value in 256 1025 2097152
 do
 	log_mustnot zfs set special_small_blocks=$value $TESTPOOL
 done