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, 24 insertions, 0 deletions

diff --git a/include/crypto/blowfish.h b/include/crypto/blowfish.h
new file mode 100644
index 000000000..9b384670b
--- /dev/null
+++ b/include/crypto/blowfish.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Common values for blowfish algorithms
+ */
+
+#ifndef _CRYPTO_BLOWFISH_H
+#define _CRYPTO_BLOWFISH_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+
+#define BF_BLOCK_SIZE 8
+#define BF_MIN_KEY_SIZE 4
+#define BF_MAX_KEY_SIZE 56
+
+struct bf_ctx {
+	u32 p[18];
+	u32 s[1024];
+};
+
+int blowfish_setkey(struct crypto_tfm *tfm, const u8 *key,
+		    unsigned int key_len);
+
+#endif