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, 39 insertions, 0 deletions

diff --git a/include/crypto/cryptd.h b/include/crypto/cryptd.h
new file mode 100644
index 000000000..29c5878a3
--- /dev/null
+++ b/include/crypto/cryptd.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Software async crypto daemon
+ *
+ * Added AEAD support to cryptd.
+ *    Authors: Tadeusz Struk (tadeusz.struk@intel.com)
+ *             Adrian Hoban <adrian.hoban@intel.com>
+ *             Gabriele Paoloni <gabriele.paoloni@intel.com>
+ *             Aidan O'Mahony (aidan.o.mahony@intel.com)
+ *    Copyright (c) 2010, Intel Corporation.
+ */
+
+#ifndef _CRYPTO_CRYPT_H
+#define _CRYPTO_CRYPT_H
+
+#include <linux/types.h>
+
+#include <crypto/aead.h>
+
+struct cryptd_aead {
+	struct crypto_aead base;
+};
+
+static inline struct cryptd_aead *__cryptd_aead_cast(
+	struct crypto_aead *tfm)
+{
+	return (struct cryptd_aead *)tfm;
+}
+
+struct cryptd_aead *cryptd_alloc_aead(const char *alg_name,
+					  u32 type, u32 mask);
+
+struct crypto_aead *cryptd_aead_child(struct cryptd_aead *tfm);
+/* Must be called without moving CPUs. */
+bool cryptd_aead_queued(struct cryptd_aead *tfm);
+
+void cryptd_free_aead(struct cryptd_aead *tfm);
+
+#endif