From: Jan Beulich <jbeulich@suse.com>
Date: Fri, 17 Sep 2021 12:49:04 +0200
Subject: xen/pci-swiotlb: reduce visibility of symbols
Git-commit: 8e1034a526652f265ed993fab7f659eb8ae4b6f0
Patch-mainline: v5.15-rc3
References: bsc#1205701

xen_swiotlb and pci_xen_swiotlb_init() are only used within the file
defining them, so make them static and remove the stubs. Otoh
pci_xen_swiotlb_detect() has a use (as function pointer) from the main
pci-swiotlb.c file - convert its stub to a #define to NULL.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Link: https://lore.kernel.org/r/aef5fc33-9c02-4df0-906a-5c813142e13c@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 arch/x86/include/asm/xen/swiotlb-xen.h | 6 +-----
 arch/x86/xen/pci-swiotlb-xen.c         | 4 ++--
 2 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/xen/swiotlb-xen.h b/arch/x86/include/asm/xen/swiotlb-xen.h
index 6b56d0d45d15..66b4ddde7743 100644
--- a/arch/x86/include/asm/xen/swiotlb-xen.h
+++ b/arch/x86/include/asm/xen/swiotlb-xen.h
@@ -3,14 +3,10 @@
 #define _ASM_X86_SWIOTLB_XEN_H
 
 #ifdef CONFIG_SWIOTLB_XEN
-extern int xen_swiotlb;
 extern int __init pci_xen_swiotlb_detect(void);
-extern void __init pci_xen_swiotlb_init(void);
 extern int pci_xen_swiotlb_init_late(void);
 #else
-#define xen_swiotlb (0)
-static inline int __init pci_xen_swiotlb_detect(void) { return 0; }
-static inline void __init pci_xen_swiotlb_init(void) { }
+#define pci_xen_swiotlb_detect NULL
 static inline int pci_xen_swiotlb_init_late(void) { return -ENXIO; }
 #endif
 
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index 54f9aa7e8457..46df59aeaa06 100644
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -18,7 +18,7 @@
 #endif
 #include <linux/export.h>
 
-int xen_swiotlb __read_mostly;
+static int xen_swiotlb __read_mostly;
 
 /*
  * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
@@ -56,7 +56,7 @@ int __init pci_xen_swiotlb_detect(void)
 	return xen_swiotlb;
 }
 
-void __init pci_xen_swiotlb_init(void)
+static void __init pci_xen_swiotlb_init(void)
 {
 	if (xen_swiotlb) {
 		xen_swiotlb_init_early();