Move range_tree, btree, highbit64 to common code

Break out the range_tree, btree, and highbit64/lowbit64 code from kernel
space into shared kernel and userspace code.  This is needed for the
updated `zpool status -vv` error byte range reporting that will be
coming in a future commit.  That commit needs the range_tree code in
kernel and userspace.

Reviewed-by: Rob Norris <robn@despairlabs.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #18133

module/zfs/btree.c

@@ -21,7 +21,11 @@
 #include	<sys/bitops.h>
 #include	<sys/zfs_context.h>
 
-kmem_cache_t *zfs_btree_leaf_cache;
+#ifndef _KERNEL
+#define	panic(...) PANIC(__VA_ARGS__)
+#endif
+
+kmem_cache_t *zfs_btree_leaf_cache = NULL;
 
 /*
  * Control the extent of the verification that occurs when zfs_btree_verify is
@@ -106,6 +110,8 @@ zfs_btree_poison_node(zfs_btree_t *tree, zfs_btree_hdr_t *hdr)
 		    tree->bt_leaf_size - offsetof(zfs_btree_leaf_t, btl_elems) -
 		    (hdr->bth_first + hdr->bth_count) * size);
 	}
+#else
+	(void) tree; (void) hdr;
 #endif
 }
 
@@ -132,6 +138,8 @@ zfs_btree_poison_node_at(zfs_btree_t *tree, zfs_btree_hdr_t *hdr,
 		(void) memset(leaf->btl_elems +
 		    (hdr->bth_first + idx) * size, 0x0f, count * size);
 	}
+#else
+	(void) tree; (void) hdr; (void) idx; (void) count;
 #endif
 }
 
@@ -158,6 +166,8 @@ zfs_btree_verify_poison_at(zfs_btree_t *tree, zfs_btree_hdr_t *hdr,
 			    * size + i], ==, 0x0f);
 		}
 	}
+#else
+	(void) tree; (void) hdr; (void) idx;
 #endif
 }
 
@@ -196,6 +206,9 @@ void
 zfs_btree_create(zfs_btree_t *tree, int (*compar) (const void *, const void *),
     bt_find_in_buf_f bt_find_in_buf, size_t size)
 {
+	/* Verify zfs_btree_init() was called before zfs_btree_create() */
+	ASSERT(zfs_btree_leaf_cache != NULL);
+
 	zfs_btree_create_custom(tree, compar, bt_find_in_buf, size,
 	    BTREE_LEAF_SIZE);
 }
@@ -2185,6 +2198,8 @@ zfs_btree_verify_poison(zfs_btree_t *tree)
 	if (tree->bt_height == -1)
 		return;
 	zfs_btree_verify_poison_helper(tree, tree->bt_root);
+#else
+	(void) tree;
 #endif
 }
 

module/zfs/range_tree.c

@@ -34,6 +34,16 @@
 #include <sys/dnode.h>
 #include <sys/zio.h>
 #include <sys/range_tree.h>
+#include <sys/sysmacros.h>
+
+#ifndef _KERNEL
+/*
+ * Need the extra 'abort()' here since is possible for PANIC() to return, and
+ * our panic() usage in this file assumes it's NORETURN.
+ */
+#define	panic(...) do {PANIC(__VA_ARGS__); abort(); } while (0);
+#define	zfs_panic_recover(...) panic(__VA_ARGS__)
+#endif
 
 /*
  * Range trees are tree-based data structures that can be used to
@@ -116,12 +126,10 @@ zfs_range_tree_stat_verify(zfs_range_tree_t *rt)
 	}
 
 	for (i = 0; i < ZFS_RANGE_TREE_HISTOGRAM_SIZE; i++) {
-		if (hist[i] != rt->rt_histogram[i]) {
-			zfs_dbgmsg("i=%d, hist=%px, hist=%llu, rt_hist=%llu",
-			    i, hist, (u_longlong_t)hist[i],
-			    (u_longlong_t)rt->rt_histogram[i]);
-		}
-		VERIFY3U(hist[i], ==, rt->rt_histogram[i]);
+		VERIFY3UF(hist[i], ==, rt->rt_histogram[i],
+		    "i=%d, hist=%px, hist=%llu, rt_hist=%llu",
+		    i, hist, (u_longlong_t)hist[i],
+		    (u_longlong_t)rt->rt_histogram[i]);
 	}
 }