[RFC PATCH v3 5/6] virt: bao: consolidate the IPC hypercall ID in include/linux/bao.h

[João Peixoto]

The IPC shared-memory hypercall ID was passed as a parameter through each
architecture's bao_ipcshmem_hypercall() and defined locally in ipcshmem.c.
Define it once in include/linux/bao.h, next to the Remote I/O hypercall
ID, and reference it directly from the arch helpers. As there is only one
IPC hypercall, this also lets bao_ipcshmem_hypercall() drop its
hypercall_id parameter.

Signed-off-by: João Peixoto <jpeixoto@xxxxxxxxx>
---
v3:
- Rewrite the commit message to explain why the ID is consolidated and to
  describe the bao_ipcshmem_hypercall() parameter removal it performs
  (Greg KH).
- The helper now takes a single argument and fits on one line; unwrap the
  remaining few-char line wraps (Andrew Jones).

 arch/arm/include/asm/bao.h           | 5 ++---
 arch/arm64/include/asm/bao.h         | 5 ++---
 arch/riscv/include/asm/bao.h         | 6 ++----
 drivers/virt/bao/ipcshmem/ipcshmem.c | 5 +----
 include/linux/bao.h                  | 3 +++
 5 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/arch/arm/include/asm/bao.h b/arch/arm/include/asm/bao.h
index eca258cc94e3..a7d608493723 100644
--- a/arch/arm/include/asm/bao.h
+++ b/arch/arm/include/asm/bao.h
@@ -16,14 +16,13 @@
 #include <linux/arm-smccc.h>
 #include <linux/bao.h>
 
-static inline unsigned long bao_ipcshmem_hypercall(unsigned long hypercall_id,
-						   unsigned long ipcshmem_id)
+static inline unsigned long bao_ipcshmem_hypercall(unsigned long ipcshmem_id)
 {
 	struct arm_smccc_res res;
 
 	arm_smccc_hvc(ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32,
 					 ARM_SMCCC_OWNER_VENDOR_HYP,
-					 hypercall_id),
+					 BAO_IPCSHMEM_HYPERCALL_ID),
 		      ipcshmem_id, 0, 0, 0, 0, 0, 0, &res);
 
 	return res.a0;
diff --git a/arch/arm64/include/asm/bao.h b/arch/arm64/include/asm/bao.h
index 1dc09a2c261b..5bd2a8c9905d 100644
--- a/arch/arm64/include/asm/bao.h
+++ b/arch/arm64/include/asm/bao.h
@@ -16,14 +16,13 @@
 #include <linux/arm-smccc.h>
 #include <linux/bao.h>
 
-static inline unsigned long bao_ipcshmem_hypercall(unsigned long hypercall_id,
-						   unsigned long ipcshmem_id)
+static inline unsigned long bao_ipcshmem_hypercall(unsigned long ipcshmem_id)
 {
 	struct arm_smccc_res res;
 
 	arm_smccc_hvc(ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_64,
 					 ARM_SMCCC_OWNER_VENDOR_HYP,
-					 hypercall_id),
+					 BAO_IPCSHMEM_HYPERCALL_ID),
 		      ipcshmem_id, 0, 0, 0, 0, 0, 0, &res);
 
 	return res.a0;
diff --git a/arch/riscv/include/asm/bao.h b/arch/riscv/include/asm/bao.h
index 6dc0cb13c94c..a587a6abd54e 100644
--- a/arch/riscv/include/asm/bao.h
+++ b/arch/riscv/include/asm/bao.h
@@ -26,13 +26,11 @@
  */
 #define BAO_SBI_EXT_ID 0x08000ba0
 
-static inline unsigned long bao_ipcshmem_hypercall(unsigned long hypercall_id,
-						   unsigned long ipcshmem_id)
+static inline unsigned long bao_ipcshmem_hypercall(unsigned long ipcshmem_id)
 {
 	struct sbiret ret;
 
-	ret = sbi_ecall(BAO_SBI_EXT_ID, hypercall_id, ipcshmem_id, 0, 0, 0, 0,
-			0);
+	ret = sbi_ecall(BAO_SBI_EXT_ID, BAO_IPCSHMEM_HYPERCALL_ID, ipcshmem_id, 0, 0, 0, 0, 0);
 
 	return ret.error;
 }
diff --git a/drivers/virt/bao/ipcshmem/ipcshmem.c b/drivers/virt/bao/ipcshmem/ipcshmem.c
index 0d46d89ee788..5bf37c1c7933 100644
--- a/drivers/virt/bao/ipcshmem/ipcshmem.c
+++ b/drivers/virt/bao/ipcshmem/ipcshmem.c
@@ -14,9 +14,6 @@
 
 #define BAO_IPCSHMEM_NAME_LEN 16
 
-/* IPC through shared-memory hypercall ID */
-#define BAO_IPCSHMEM_HYPERCALL_ID 0x1
-
 struct bao_ipcshmem {
 	struct miscdevice miscdev;
 	u32 id;
@@ -104,7 +101,7 @@ static ssize_t bao_ipcshmem_write(struct file *filp, const char __user *buf,
 	*ppos += count;
 
 	/* Notify Bao hypervisor */
-	bao_ipcshmem_hypercall(BAO_IPCSHMEM_HYPERCALL_ID, bao->id);
+	bao_ipcshmem_hypercall(bao->id);
 
 	return count;
 }
diff --git a/include/linux/bao.h b/include/linux/bao.h
index 076f071086b6..17d6ea472521 100644
--- a/include/linux/bao.h
+++ b/include/linux/bao.h
@@ -15,6 +15,9 @@
 
 #include <linux/types.h>
 
+/* IPC through shared-memory hypercall ID */
+#define BAO_IPCSHMEM_HYPERCALL_ID 0x1
+
 /* Remote I/O Hypercall ID */
 #define BAO_REMIO_HYPERCALL_ID 0x2
 
-- 
2.43.0