[PATCH V2 2/4] RISC-V: KVM: AIA: Replace global HGEI count with simple enabled bool

[guoren at kernel.org]

From: "Guo Ren (Alibaba DAMO Academy)" <guoren at kernel.org>

Now that HGEI line management is fully per-CPU (via struct
aia_hgei_control::nr_hgei), the global `kvm_riscv_aia_nr_hgei`
is no longer needed. Replace it with a simple `bool
kvm_riscv_aia_hgei_enabled` that only indicates whether HGEI
support is available at all.

Signed-off-by: Guo Ren (Alibaba DAMO Academy) <guoren at kernel.org>
---
 arch/riscv/include/asm/kvm_aia.h |  2 +-
 arch/riscv/kvm/aia.c             | 18 ++++++++----------
 arch/riscv/kvm/aia_device.c      |  4 ++--
 arch/riscv/kvm/main.c            |  3 +--
 4 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/arch/riscv/include/asm/kvm_aia.h b/arch/riscv/include/asm/kvm_aia.h
index b04ecdd1a860..e8749ac6bed7 100644
--- a/arch/riscv/include/asm/kvm_aia.h
+++ b/arch/riscv/include/asm/kvm_aia.h
@@ -79,7 +79,7 @@ struct kvm_vcpu_aia {
 
 #define irqchip_in_kernel(k)		((k)->arch.aia.in_kernel)
 
-extern unsigned int kvm_riscv_aia_nr_hgei;
+extern bool kvm_riscv_aia_hgei_enabled;
 extern unsigned int kvm_riscv_aia_max_ids;
 DECLARE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
 #define kvm_riscv_aia_available() \
diff --git a/arch/riscv/kvm/aia.c b/arch/riscv/kvm/aia.c
index a23729052cfb..70ff1d25dd99 100644
--- a/arch/riscv/kvm/aia.c
+++ b/arch/riscv/kvm/aia.c
@@ -28,7 +28,7 @@ struct aia_hgei_control {
 static DEFINE_PER_CPU(struct aia_hgei_control, aia_hgei);
 static int hgei_parent_irq;
 
-unsigned int kvm_riscv_aia_nr_hgei;
+bool kvm_riscv_aia_hgei_enabled;
 unsigned int kvm_riscv_aia_max_ids;
 DEFINE_STATIC_KEY_FALSE(kvm_riscv_aia_available);
 
@@ -491,7 +491,7 @@ static int aia_hgei_init(void)
 	struct irq_domain *domain;
 
 	/* Skip SGEI interrupt setup for zero guest external interrupts */
-	if (!kvm_riscv_aia_nr_hgei)
+	if (!kvm_riscv_aia_hgei_enabled)
 		goto skip_sgei_interrupt;
 
 	/* Find INTC irq domain */
@@ -524,7 +524,7 @@ static int aia_hgei_init(void)
 static void aia_hgei_exit(void)
 {
 	/* Do nothing for zero guest external interrupts */
-	if (!kvm_riscv_aia_nr_hgei)
+	if (!kvm_riscv_aia_hgei_enabled)
 		return;
 
 	/* Free per-CPU SGEI interrupt */
@@ -631,6 +631,7 @@ int kvm_riscv_aia_init(void)
 {
 	int rc;
 	const struct imsic_global_config *gc;
+	unsigned int kvm_riscv_aia_nr_hgei;
 
 	if (!riscv_isa_extension_available(NULL, SxAIA))
 		return -ENODEV;
@@ -641,21 +642,18 @@ int kvm_riscv_aia_init(void)
 	kvm_riscv_aia_nr_hgei = fls_long(csr_read(CSR_HGEIE));
 	csr_write(CSR_HGEIE, 0);
 	if (kvm_riscv_aia_nr_hgei)
-		kvm_riscv_aia_nr_hgei--;
+		kvm_riscv_aia_hgei_enabled = true;
 
 	/*
 	 * Number of usable HGEI lines should be minimum of per-HART
 	 * IMSIC guest files and number of bits in HGEIE
 	 */
-	if (gc)
-		kvm_riscv_aia_nr_hgei = min((ulong)kvm_riscv_aia_nr_hgei,
-					    gc->nr_guest_files);
-	else
-		kvm_riscv_aia_nr_hgei = 0;
+	if (!gc)
+		kvm_riscv_aia_hgei_enabled = 0;
 
 	/* Find number of guest MSI IDs */
 	kvm_riscv_aia_max_ids = IMSIC_MAX_ID;
-	if (gc && kvm_riscv_aia_nr_hgei)
+	if (gc && kvm_riscv_aia_hgei_enabled)
 		kvm_riscv_aia_max_ids = gc->nr_guest_ids + 1;
 
 	/* Initialize guest external interrupt line management */
diff --git a/arch/riscv/kvm/aia_device.c b/arch/riscv/kvm/aia_device.c
index 3d1e81e2a36b..5b45b1114425 100644
--- a/arch/riscv/kvm/aia_device.c
+++ b/arch/riscv/kvm/aia_device.c
@@ -71,7 +71,7 @@ static int aia_config(struct kvm *kvm, unsigned long type,
 				 * external interrupts (i.e. non-zero
 				 * VS-level IMSIC pages).
 				 */
-				if (!kvm_riscv_aia_nr_hgei)
+				if (!kvm_riscv_aia_hgei_enabled)
 					return -EINVAL;
 				break;
 			default:
@@ -628,7 +628,7 @@ void kvm_riscv_aia_init_vm(struct kvm *kvm)
 	 */
 
 	/* Initialize default values in AIA global context */
-	aia->mode = (kvm_riscv_aia_nr_hgei) ?
+	aia->mode = (kvm_riscv_aia_hgei_enabled) ?
 		KVM_DEV_RISCV_AIA_MODE_AUTO : KVM_DEV_RISCV_AIA_MODE_EMUL;
 	aia->nr_ids = kvm_riscv_aia_max_ids - 1;
 	aia->nr_sources = 0;
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index cb8a65273c1f..bcfa139f4871 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -169,8 +169,7 @@ static int __init riscv_kvm_init(void)
 	kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
 
 	if (kvm_riscv_aia_available())
-		kvm_info("AIA available with %d guest external interrupts\n",
-			 kvm_riscv_aia_nr_hgei);
+		kvm_info("AIA available with guest external interrupts\n");
 
 	kvm_riscv_setup_vendor_features();
 
-- 
2.43.0