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Revision 8c89ecf5c13b0504018c5045896a0b78d5d811e6 authored by Alexander Potapenko on 11 January 2023, 10:50:12 UTC, committed by Alexander Potapenko on 07 February 2023, 09:50:25 UTC 
kmsan: silence -Wmissing-prototypes warnings
 
When building the kernel with W=1, the compiler reports numerous
warnings about the missing prototypes for KMSAN instrumentation hooks.

Because these functions are not supposed to be called explicitly by the
kernel code (calls to them are emitted by the compiler), they do not
have to be declared in the headers. Instead, we add forward declarations
right before the definitions to silence the warnings produced by
-Wmissing-prototypes.

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/202301020356.dFruA4I5-lkp@intel.com/T/
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Suggested-by: Marco Elver <elver@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
1 parent 8b0ffea
Raw File
projid.h 
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_PROJID_H
#define _LINUX_PROJID_H

/*
 * A set of types for the internal kernel types representing project ids.
 *
 * The types defined in this header allow distinguishing which project ids in
 * the kernel are values used by userspace and which project id values are
 * the internal kernel values.  With the addition of user namespaces the values
 * can be different.  Using the type system makes it possible for the compiler
 * to detect when we overlook these differences.
 *
 */
#include <linux/types.h>

struct user_namespace;
extern struct user_namespace init_user_ns;

typedef __kernel_uid32_t projid_t;

typedef struct {
	projid_t val;
} kprojid_t;

static inline projid_t __kprojid_val(kprojid_t projid)
{
	return projid.val;
}

#define KPROJIDT_INIT(value) (kprojid_t){ value }

#define INVALID_PROJID KPROJIDT_INIT(-1)
#define OVERFLOW_PROJID 65534

static inline bool projid_eq(kprojid_t left, kprojid_t right)
{
	return __kprojid_val(left) == __kprojid_val(right);
}

static inline bool projid_lt(kprojid_t left, kprojid_t right)
{
	return __kprojid_val(left) < __kprojid_val(right);
}

static inline bool projid_valid(kprojid_t projid)
{
	return !projid_eq(projid, INVALID_PROJID);
}

#ifdef CONFIG_USER_NS

extern kprojid_t make_kprojid(struct user_namespace *from, projid_t projid);

extern projid_t from_kprojid(struct user_namespace *to, kprojid_t projid);
extern projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t projid);

static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
{
	return from_kprojid(ns, projid) != (projid_t)-1;
}

#else

static inline kprojid_t make_kprojid(struct user_namespace *from, projid_t projid)
{
	return KPROJIDT_INIT(projid);
}

static inline projid_t from_kprojid(struct user_namespace *to, kprojid_t kprojid)
{
	return __kprojid_val(kprojid);
}

static inline projid_t from_kprojid_munged(struct user_namespace *to, kprojid_t kprojid)
{
	projid_t projid = from_kprojid(to, kprojid);
	if (projid == (projid_t)-1)
		projid = OVERFLOW_PROJID;
	return projid;
}

static inline bool kprojid_has_mapping(struct user_namespace *ns, kprojid_t projid)
{
	return true;
}

#endif /* CONFIG_USER_NS */

#endif /* _LINUX_PROJID_H */
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