thread_info: factor out restart_block

Since commit f56141e3e2 ("all arches, signal: move restart_block
to struct task_struct"), thread_info and restart_block have been
logically distinct, yet struct restart_block is still defined in
<linux/thread_info.h>.

At least one architecture (erroneously) uses restart_block as part of
its thread_info, and thus the definition of restart_block must come
before the include of <asm/thread_info>. Subsequent patches in this
series need to shuffle the order of includes and definitions in
<linux/thread_info.h>, and will make this ordering fragile.

This patch moves the definition of restart_block out to its own header.
This serves as generic cleanup, logically separating thread_info and
restart_block, and also makes it easier to avoid fragility.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Mark Rutland 2016-10-19 19:28:12 +01:00 committed by Catalin Marinas
parent 094339443e
commit 53d74d056a
2 changed files with 52 additions and 40 deletions

View File

@ -0,0 +1,51 @@
/*
* Common syscall restarting data
*/
#ifndef __LINUX_RESTART_BLOCK_H
#define __LINUX_RESTART_BLOCK_H
#include <linux/compiler.h>
#include <linux/types.h>
struct timespec;
struct compat_timespec;
struct pollfd;
/*
* System call restart block.
*/
struct restart_block {
long (*fn)(struct restart_block *);
union {
/* For futex_wait and futex_wait_requeue_pi */
struct {
u32 __user *uaddr;
u32 val;
u32 flags;
u32 bitset;
u64 time;
u32 __user *uaddr2;
} futex;
/* For nanosleep */
struct {
clockid_t clockid;
struct timespec __user *rmtp;
#ifdef CONFIG_COMPAT
struct compat_timespec __user *compat_rmtp;
#endif
u64 expires;
} nanosleep;
/* For poll */
struct {
struct pollfd __user *ufds;
int nfds;
int has_timeout;
unsigned long tv_sec;
unsigned long tv_nsec;
} poll;
};
};
extern long do_no_restart_syscall(struct restart_block *parm);
#endif /* __LINUX_RESTART_BLOCK_H */

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@ -9,51 +9,12 @@
#include <linux/types.h>
#include <linux/bug.h>
struct timespec;
struct compat_timespec;
#include <linux/restart_block.h>
#ifdef CONFIG_THREAD_INFO_IN_TASK
#define current_thread_info() ((struct thread_info *)current)
#endif
/*
* System call restart block.
*/
struct restart_block {
long (*fn)(struct restart_block *);
union {
/* For futex_wait and futex_wait_requeue_pi */
struct {
u32 __user *uaddr;
u32 val;
u32 flags;
u32 bitset;
u64 time;
u32 __user *uaddr2;
} futex;
/* For nanosleep */
struct {
clockid_t clockid;
struct timespec __user *rmtp;
#ifdef CONFIG_COMPAT
struct compat_timespec __user *compat_rmtp;
#endif
u64 expires;
} nanosleep;
/* For poll */
struct {
struct pollfd __user *ufds;
int nfds;
int has_timeout;
unsigned long tv_sec;
unsigned long tv_nsec;
} poll;
};
};
extern long do_no_restart_syscall(struct restart_block *parm);
#include <linux/bitops.h>
#include <asm/thread_info.h>