When PCI_IOBASE is not defined, it is set to 0 such that it is ignored
in calls to the readX/writeX primitives. This triggers clang's
-Wnull-pointer-arithmetic warning and will result in illegal accesses on
platforms that do not support I/O ports if drivers do still attempt to
access them.
Make things explicit and silence the warning by letting inb() and
friends fail with WARN_ONCE() and a 0xff... return in case PCI_IOBASE is
not defined.
Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
---
v2 -> v3:
- Added ifdefs to ioport_map() and __pci_ioport_map() since apparently at least
test configs enable CONFIG_HAS_IOPORT_MAP even on architectures which leave
PCI_IOBASE unset (kernel test robot for nds32 and ARC).
v1 -> v2:
- Instead of working around the warning with a uintptr_t PCI_IOBASE make inb()
and friends explicitly WARN_ONCE() and return 0xff... (Arnd)
include/asm-generic/io.h | 64 +++++++++++++++++++++++++++++++++++++---
1 file changed, 60 insertions(+), 4 deletions(-)
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index c6af40ce03be..aabb0a8186ee 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -440,10 +440,6 @@ static inline void writesq(volatile void __iomem *addr, const void *buffer,
#endif
#endif /* CONFIG_64BIT */
-#ifndef PCI_IOBASE
-#define PCI_IOBASE ((void __iomem *)0)
-#endif
-
#ifndef IO_SPACE_LIMIT
#define IO_SPACE_LIMIT 0xffff
#endif
@@ -458,12 +454,17 @@ static inline void writesq(volatile void __iomem *addr, const void *buffer,
#define _inb _inb
static inline u8 _inb(unsigned long addr)
{
+#ifdef PCI_IOBASE
u8 val;
__io_pbr();
val = __raw_readb(PCI_IOBASE + addr);
__io_par(val);
return val;
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+ return ~0;
+#endif
}
#endif
@@ -471,12 +472,17 @@ static inline u8 _inb(unsigned long addr)
#define _inw _inw
static inline u16 _inw(unsigned long addr)
{
+#ifdef PCI_IOBASE
u16 val;
__io_pbr();
val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
__io_par(val);
return val;
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+ return ~0;
+#endif
}
#endif
@@ -484,12 +490,17 @@ static inline u16 _inw(unsigned long addr)
#define _inl _inl
static inline u32 _inl(unsigned long addr)
{
+#ifdef PCI_IOBASE
u32 val;
__io_pbr();
val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
__io_par(val);
return val;
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+ return ~0;
+#endif
}
#endif
@@ -497,9 +508,13 @@ static inline u32 _inl(unsigned long addr)
#define _outb _outb
static inline void _outb(u8 value, unsigned long addr)
{
+#ifdef PCI_IOBASE
__io_pbw();
__raw_writeb(value, PCI_IOBASE + addr);
__io_paw();
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -507,9 +522,13 @@ static inline void _outb(u8 value, unsigned long addr)
#define _outw _outw
static inline void _outw(u16 value, unsigned long addr)
{
+#ifdef PCI_IOBASE
__io_pbw();
__raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
__io_paw();
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -517,9 +536,13 @@ static inline void _outw(u16 value, unsigned long addr)
#define _outl _outl
static inline void _outl(u32 value, unsigned long addr)
{
+#ifdef PCI_IOBASE
__io_pbw();
__raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
__io_paw();
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -606,7 +629,11 @@ static inline void outl_p(u32 value, unsigned long addr)
#define insb insb
static inline void insb(unsigned long addr, void *buffer, unsigned int count)
{
+#ifdef PCI_IOBASE
readsb(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -614,7 +641,11 @@ static inline void insb(unsigned long addr, void *buffer, unsigned int count)
#define insw insw
static inline void insw(unsigned long addr, void *buffer, unsigned int count)
{
+#ifdef PCI_IOBASE
readsw(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -622,7 +653,11 @@ static inline void insw(unsigned long addr, void *buffer, unsigned int count)
#define insl insl
static inline void insl(unsigned long addr, void *buffer, unsigned int count)
{
+#ifdef PCI_IOBASE
readsl(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -631,7 +666,11 @@ static inline void insl(unsigned long addr, void *buffer, unsigned int count)
static inline void outsb(unsigned long addr, const void *buffer,
unsigned int count)
{
+#ifdef PCI_IOBASE
writesb(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -640,7 +679,11 @@ static inline void outsb(unsigned long addr, const void *buffer,
static inline void outsw(unsigned long addr, const void *buffer,
unsigned int count)
{
+#ifdef PCI_IOBASE
writesw(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -649,7 +692,11 @@ static inline void outsw(unsigned long addr, const void *buffer,
static inline void outsl(unsigned long addr, const void *buffer,
unsigned int count)
{
+#ifdef PCI_IOBASE
writesl(PCI_IOBASE + addr, buffer, count);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
@@ -1001,18 +1048,27 @@ static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size)
#define ioport_map ioport_map
static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
{
+#ifdef PCI_IOBASE
port &= IO_SPACE_LIMIT;
return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+ return NULL;
+#endif
}
#define __pci_ioport_unmap __pci_ioport_unmap
static inline void __pci_ioport_unmap(void __iomem *p)
{
+#ifdef PCI_IOBASE
uintptr_t start = (uintptr_t) PCI_IOBASE;
uintptr_t addr = (uintptr_t) p;
if (addr >= start && addr < start + IO_SPACE_LIMIT)
return;
iounmap(p);
+#else
+ WARN_ONCE(1, "No I/O port support\n");
+#endif
}
#endif
--
2.25.1
