From: Mikael Pettersson <mikpe@csd.uu.se>
Part 3/3 of perfctr control API changes:
- Changed sys_vperfctr_control() to handle variable-sized
cpu_control data. Moved cpu_control field to end of
struct vperfctr_control, added size parameter to
sys_vperfctr_control(), and changed do_vperfctr_control()
to only copy as many bytes as user-space indicates.
Together with the array-of-struct layout for per-counter
control fields, this:
* maintains API compatibility even if future processors
add more counters, and
* allows for reduced argument copying when user-space only
uses a small subset of the available counters.
- Bump version.
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/perfctr/version.h | 2 +-
25-akpm/drivers/perfctr/virtual.c | 15 +++++++++++----
25-akpm/include/linux/perfctr.h | 7 ++++---
3 files changed, 16 insertions(+), 8 deletions(-)
diff -puN drivers/perfctr/version.h~perfctr-virtual-update drivers/perfctr/version.h
--- 25/drivers/perfctr/version.h~perfctr-virtual-update 2004-11-28 00:54:09.043505472 -0800
+++ 25-akpm/drivers/perfctr/version.h 2004-11-28 00:54:09.051504256 -0800
@@ -1 +1 @@
-#define VERSION "2.7.6"
+#define VERSION "2.7.8"
diff -puN drivers/perfctr/virtual.c~perfctr-virtual-update drivers/perfctr/virtual.c
--- 25/drivers/perfctr/virtual.c~perfctr-virtual-update 2004-11-28 00:54:09.045505168 -0800
+++ 25-akpm/drivers/perfctr/virtual.c 2004-11-28 00:54:09.053503952 -0800
@@ -1,4 +1,4 @@
-/* $Id: virtual.c,v 1.107 2004/10/23 23:28:45 mikpe Exp $
+/* $Id: virtual.c,v 1.110 2004/11/24 00:38:30 mikpe Exp $
* Virtual per-process performance counters.
*
* Copyright (C) 1999-2004 Mikael Pettersson
@@ -541,6 +541,7 @@ void __vperfctr_set_cpus_allowed(struct
static int do_vperfctr_control(struct vperfctr *perfctr,
const struct vperfctr_control __user *argp,
+ unsigned int argbytes,
struct task_struct *tsk)
{
struct vperfctr_control *control;
@@ -561,9 +562,14 @@ static int do_vperfctr_control(struct vp
if (!control)
return -ENOMEM;
+ err = -EINVAL;
+ if (argbytes > sizeof *control)
+ goto out_kfree;
err = -EFAULT;
- if (copy_from_user(control, argp, sizeof *control))
+ if (copy_from_user(control, argp, argbytes))
goto out_kfree;
+ if (argbytes < sizeof *control)
+ memset((char*)control + argbytes, 0, sizeof *control - argbytes);
if (control->cpu_control.nractrs || control->cpu_control.nrictrs) {
cpumask_t old_mask, new_mask;
@@ -1046,7 +1052,8 @@ static void vperfctr_put_tsk(struct task
}
asmlinkage long sys_vperfctr_control(int fd,
- const struct vperfctr_control __user *control)
+ const struct vperfctr_control __user *argp,
+ unsigned int argbytes)
{
struct vperfctr *perfctr;
struct task_struct *tsk;
@@ -1060,7 +1067,7 @@ asmlinkage long sys_vperfctr_control(int
ret = PTR_ERR(tsk);
goto out;
}
- ret = do_vperfctr_control(perfctr, control, tsk);
+ ret = do_vperfctr_control(perfctr, argp, argbytes, tsk);
vperfctr_put_tsk(tsk);
out:
put_vperfctr(perfctr);
diff -puN include/linux/perfctr.h~perfctr-virtual-update include/linux/perfctr.h
--- 25/include/linux/perfctr.h~perfctr-virtual-update 2004-11-28 00:54:09.046505016 -0800
+++ 25-akpm/include/linux/perfctr.h 2004-11-28 00:54:09.053503952 -0800
@@ -1,4 +1,4 @@
-/* $Id: perfctr.h,v 1.83 2004/07/17 00:37:52 mikpe Exp $
+/* $Id: perfctr.h,v 1.85 2004/11/24 00:38:21 mikpe Exp $
* Performance-Monitoring Counters driver
*
* Copyright (C) 1999-2004 Mikael Pettersson
@@ -46,12 +46,12 @@ struct vperfctr_state {
/* virtual perfctr control object */
struct vperfctr_control {
int si_signo;
- struct perfctr_cpu_control cpu_control;
unsigned int preserve;
unsigned int _reserved1;
unsigned int _reserved2;
unsigned int _reserved3;
unsigned int _reserved4;
+ struct perfctr_cpu_control cpu_control;
};
/* commands for sys_vperfctr_read() */
@@ -76,7 +76,8 @@ asmlinkage long sys_perfctr_info(struct
struct perfctr_cpu_mask __user*);
asmlinkage long sys_vperfctr_open(int tid, int creat);
asmlinkage long sys_vperfctr_control(int fd,
- const struct vperfctr_control __user*);
+ const struct vperfctr_control __user *argp,
+ unsigned int argbytes);
asmlinkage long sys_vperfctr_unlink(int fd);
asmlinkage long sys_vperfctr_iresume(int fd);
asmlinkage long sys_vperfctr_read(int fd, unsigned int cmd, void __user *argp, unsigned int argbytes);
_