99441a38c3
Use control register bit defines instead of plain numbers where possible. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
129 lines
2.5 KiB
C
129 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright IBM Corp. 2016
|
|
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <asm/guarded_storage.h>
|
|
#include "entry.h"
|
|
|
|
void guarded_storage_release(struct task_struct *tsk)
|
|
{
|
|
kfree(tsk->thread.gs_cb);
|
|
kfree(tsk->thread.gs_bc_cb);
|
|
}
|
|
|
|
static int gs_enable(void)
|
|
{
|
|
struct gs_cb *gs_cb;
|
|
|
|
if (!current->thread.gs_cb) {
|
|
gs_cb = kzalloc(sizeof(*gs_cb), GFP_KERNEL);
|
|
if (!gs_cb)
|
|
return -ENOMEM;
|
|
gs_cb->gsd = 25;
|
|
preempt_disable();
|
|
local_ctl_set_bit(2, CR2_GUARDED_STORAGE_BIT);
|
|
load_gs_cb(gs_cb);
|
|
current->thread.gs_cb = gs_cb;
|
|
preempt_enable();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int gs_disable(void)
|
|
{
|
|
if (current->thread.gs_cb) {
|
|
preempt_disable();
|
|
kfree(current->thread.gs_cb);
|
|
current->thread.gs_cb = NULL;
|
|
local_ctl_clear_bit(2, CR2_GUARDED_STORAGE_BIT);
|
|
preempt_enable();
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int gs_set_bc_cb(struct gs_cb __user *u_gs_cb)
|
|
{
|
|
struct gs_cb *gs_cb;
|
|
|
|
gs_cb = current->thread.gs_bc_cb;
|
|
if (!gs_cb) {
|
|
gs_cb = kzalloc(sizeof(*gs_cb), GFP_KERNEL);
|
|
if (!gs_cb)
|
|
return -ENOMEM;
|
|
current->thread.gs_bc_cb = gs_cb;
|
|
}
|
|
if (copy_from_user(gs_cb, u_gs_cb, sizeof(*gs_cb)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
static int gs_clear_bc_cb(void)
|
|
{
|
|
struct gs_cb *gs_cb;
|
|
|
|
gs_cb = current->thread.gs_bc_cb;
|
|
current->thread.gs_bc_cb = NULL;
|
|
kfree(gs_cb);
|
|
return 0;
|
|
}
|
|
|
|
void gs_load_bc_cb(struct pt_regs *regs)
|
|
{
|
|
struct gs_cb *gs_cb;
|
|
|
|
preempt_disable();
|
|
clear_thread_flag(TIF_GUARDED_STORAGE);
|
|
gs_cb = current->thread.gs_bc_cb;
|
|
if (gs_cb) {
|
|
kfree(current->thread.gs_cb);
|
|
current->thread.gs_bc_cb = NULL;
|
|
local_ctl_set_bit(2, CR2_GUARDED_STORAGE_BIT);
|
|
load_gs_cb(gs_cb);
|
|
current->thread.gs_cb = gs_cb;
|
|
}
|
|
preempt_enable();
|
|
}
|
|
|
|
static int gs_broadcast(void)
|
|
{
|
|
struct task_struct *sibling;
|
|
|
|
read_lock(&tasklist_lock);
|
|
for_each_thread(current, sibling) {
|
|
if (!sibling->thread.gs_bc_cb)
|
|
continue;
|
|
if (test_and_set_tsk_thread_flag(sibling, TIF_GUARDED_STORAGE))
|
|
kick_process(sibling);
|
|
}
|
|
read_unlock(&tasklist_lock);
|
|
return 0;
|
|
}
|
|
|
|
SYSCALL_DEFINE2(s390_guarded_storage, int, command,
|
|
struct gs_cb __user *, gs_cb)
|
|
{
|
|
if (!MACHINE_HAS_GS)
|
|
return -EOPNOTSUPP;
|
|
switch (command) {
|
|
case GS_ENABLE:
|
|
return gs_enable();
|
|
case GS_DISABLE:
|
|
return gs_disable();
|
|
case GS_SET_BC_CB:
|
|
return gs_set_bc_cb(gs_cb);
|
|
case GS_CLEAR_BC_CB:
|
|
return gs_clear_bc_cb();
|
|
case GS_BROADCAST:
|
|
return gs_broadcast();
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|