system/freebsd-src
system/freebsd-src
1
0
Fork 0
mirror of https://github.com/freebsd/freebsd-src synced 2024-09-06 09:10:28 +00:00
Code Issues Packages Projects Releases Wiki Activity

swapoff(2): replace special device name argument with a structure

Browse source 
For compatibility, add a placeholder pointer to the start of the
added struct swapoff_new_args, and use it to distinguish old vs. new
style of syscall invocation.

Reviewed by:	markj
Discussed with:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D33165
This commit is contained in:
Konstantin Belousov 2021-11-29 18:26:31 +02:00
parent 6df359449f
commit a4e4132fa3
2 changed files with 33 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

27
sys/vm/swap_pager.c
View file

@ -2491,15 +2491,38 @@ sys_swapoff(struct thread *td, struct swapoff_args *uap)
struct vnode *vp;
struct nameidata nd;
struct swdevt *sp;
int error;
struct swapoff_new_args sa;
int error, probe_byte;
error = priv_check(td, PRIV_SWAPOFF);
if (error)
return (error);
/*
* Detect old vs. new-style swapoff(2) syscall. The first
* pointer in the memory pointed to by uap->name is NULL for
* the new variant.
*/
probe_byte = fubyte(uap->name);
switch (probe_byte) {
case -1:
return (EFAULT);
case 0:
error = copyin(uap->name, &sa, sizeof(sa));
if (error != 0)
return (error);
if (sa.flags != 0)
return (EINVAL);
break;
default:
bzero(&sa, sizeof(sa));
sa.name = uap->name;
break;
}
sx_xlock(&swdev_syscall_lock);
NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, UIO_USERSPACE, uap->name);
NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, UIO_USERSPACE, sa.name);
error = namei(&nd);
if (error)
goto done;

8
sys/vm/swap_pager.h
View file

@ -69,6 +69,14 @@ struct swdevt {
#define SW_UNMAPPED 0x01
#define SW_CLOSING 0x04
struct swapoff_new_args {
const char *name_old_syscall;
const char *name;
u_int flags;
u_int pad0;
uintptr_t pad1[8];
};
#ifdef _KERNEL
extern int swap_pager_avail;