[PATCH 4.9 23/32] kdev_t: always inline major/minor helper functions

From: Greg Kroah-Hartman
Date: Thu Jan 07 2021 - 09:20:36 EST


From: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>

commit aa8c7db494d0a83ecae583aa193f1134ef25d506 upstream.

Silly GCC doesn't always inline these trivial functions.

Fixes the following warning:

arch/x86/kernel/sys_ia32.o: warning: objtool: cp_stat64()+0xd8: call to new_encode_dev() with UACCESS enabled

Link: https://lkml.kernel.org/r/984353b44a4484d86ba9f73884b7306232e25e30.1608737428.git.jpoimboe@xxxxxxxxxx
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> [build-tested]
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
include/linux/kdev_t.h | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)

--- a/include/linux/kdev_t.h
+++ b/include/linux/kdev_t.h
@@ -20,61 +20,61 @@
})

/* acceptable for old filesystems */
-static inline bool old_valid_dev(dev_t dev)
+static __always_inline bool old_valid_dev(dev_t dev)
{
return MAJOR(dev) < 256 && MINOR(dev) < 256;
}

-static inline u16 old_encode_dev(dev_t dev)
+static __always_inline u16 old_encode_dev(dev_t dev)
{
return (MAJOR(dev) << 8) | MINOR(dev);
}

-static inline dev_t old_decode_dev(u16 val)
+static __always_inline dev_t old_decode_dev(u16 val)
{
return MKDEV((val >> 8) & 255, val & 255);
}

-static inline u32 new_encode_dev(dev_t dev)
+static __always_inline u32 new_encode_dev(dev_t dev)
{
unsigned major = MAJOR(dev);
unsigned minor = MINOR(dev);
return (minor & 0xff) | (major << 8) | ((minor & ~0xff) << 12);
}

-static inline dev_t new_decode_dev(u32 dev)
+static __always_inline dev_t new_decode_dev(u32 dev)
{
unsigned major = (dev & 0xfff00) >> 8;
unsigned minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
return MKDEV(major, minor);
}

-static inline u64 huge_encode_dev(dev_t dev)
+static __always_inline u64 huge_encode_dev(dev_t dev)
{
return new_encode_dev(dev);
}

-static inline dev_t huge_decode_dev(u64 dev)
+static __always_inline dev_t huge_decode_dev(u64 dev)
{
return new_decode_dev(dev);
}

-static inline int sysv_valid_dev(dev_t dev)
+static __always_inline int sysv_valid_dev(dev_t dev)
{
return MAJOR(dev) < (1<<14) && MINOR(dev) < (1<<18);
}

-static inline u32 sysv_encode_dev(dev_t dev)
+static __always_inline u32 sysv_encode_dev(dev_t dev)
{
return MINOR(dev) | (MAJOR(dev) << 18);
}

-static inline unsigned sysv_major(u32 dev)
+static __always_inline unsigned sysv_major(u32 dev)
{
return (dev >> 18) & 0x3fff;
}

-static inline unsigned sysv_minor(u32 dev)
+static __always_inline unsigned sysv_minor(u32 dev)
{
return dev & 0x3ffff;
}