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, 40 insertions, 0 deletions

diff --git a/arch/mips/kvm/interrupt.c b/arch/mips/kvm/interrupt.c
new file mode 100644
index 000000000..895a6f178
--- /dev/null
+++ b/arch/mips/kvm/interrupt.c
@@ -0,0 +1,40 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * KVM/MIPS: Interrupt delivery
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/memblock.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+
+#include <linux/kvm_host.h>
+
+#include "interrupt.h"
+
+void kvm_mips_deliver_interrupts(struct kvm_vcpu *vcpu, u32 cause)
+{
+	unsigned long *pending = &vcpu->arch.pending_exceptions;
+	unsigned long *pending_clr = &vcpu->arch.pending_exceptions_clr;
+	unsigned int priority;
+
+	for_each_set_bit(priority, pending_clr, MIPS_EXC_MAX + 1)
+		kvm_mips_callbacks->irq_clear(vcpu, priority, cause);
+
+	for_each_set_bit(priority, pending, MIPS_EXC_MAX + 1)
+		kvm_mips_callbacks->irq_deliver(vcpu, priority, cause);
+}
+
+int kvm_mips_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return test_bit(MIPS_EXC_INT_TIMER, &vcpu->arch.pending_exceptions);
+}