KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 34 insertions, 0 deletions

diff --git a/include/net/rpl.h b/include/net/rpl.h
new file mode 100644
index 000000000..74734191c
--- /dev/null
+++ b/include/net/rpl.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  RPL implementation
+ *
+ *  Author:
+ *  (C) 2020 Alexander Aring <alex.aring@gmail.com>
+ */
+
+#ifndef _NET_RPL_H
+#define _NET_RPL_H
+
+#include <linux/rpl.h>
+
+#if IS_ENABLED(CONFIG_IPV6_RPL_LWTUNNEL)
+extern int rpl_init(void);
+extern void rpl_exit(void);
+#else
+static inline int rpl_init(void)
+{
+	return 0;
+}
+
+static inline void rpl_exit(void) {}
+#endif
+
+void ipv6_rpl_srh_decompress(struct ipv6_rpl_sr_hdr *outhdr,
+			     const struct ipv6_rpl_sr_hdr *inhdr,
+			     const struct in6_addr *daddr, unsigned char n);
+
+void ipv6_rpl_srh_compress(struct ipv6_rpl_sr_hdr *outhdr,
+			   const struct ipv6_rpl_sr_hdr *inhdr,
+			   const struct in6_addr *daddr, unsigned char n);
+
+#endif /* _NET_RPL_H */