[PATCH] s390/io: Fix ioremap and iounmap undefinded issue for s390

From: Chunyan Zhang
Date: Fri Sep 03 2021 - 03:57:18 EST

From: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>

There would not be ioremap and iounmap implementations if CONFIG_PCI is
not set for s390, so add default declarations of these two functionsi
for the case to avoid 'undefined reference' issue.

Fixes: 71ba41c9b1d9 ("s390/pci: provide support for MIO instructions")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Chunyan Zhang <chunyan.zhang@xxxxxxxxxx>
The issue was reported from https://lkml.org/lkml/2021/8/1/18
arch/s390/include/asm/io.h | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h
index e3882b012bfa..9438370c6445 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -23,11 +23,8 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
#define IO_SPACE_LIMIT 0

void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot);
-void __iomem *ioremap(phys_addr_t addr, size_t size);
void __iomem *ioremap_wc(phys_addr_t addr, size_t size);
void __iomem *ioremap_wt(phys_addr_t addr, size_t size);
-void iounmap(volatile void __iomem *addr);
static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
return NULL;
@@ -39,6 +36,9 @@ static inline void ioport_unmap(void __iomem *p)


+void __iomem *ioremap(phys_addr_t addr, size_t size);
+void iounmap(volatile void __iomem *addr);
* s390 needs a private implementation of pci_iomap since ioremap with its
* offset parameter isn't sufficient. That's because BAR spaces are not
@@ -70,6 +70,15 @@ static inline void ioport_unmap(void __iomem *p)
#define __raw_writel zpci_write_u32
#define __raw_writeq zpci_write_u64

+static inline void __iomem *ioremap(unsigned long offset, unsigned long size)
+ return (void __iomem *) offset;
+static inline void iounmap(void __iomem *addr)
#endif /* CONFIG_PCI */

#include <asm-generic/io.h>