mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-09 21:26:40 +07:00
1b9f23727a
The posix_clock_poll function is supposed to return a bit mask of POLLxxx values. However, in case the hardware has disappeared (due to hot plugging for example) this code returns -ENODEV in a futile attempt to throw an error at the file descriptor level. The kernel's file_operations interface does not accept such error codes from the poll method. Instead, this function aught to return POLLERR. The value -ENODEV does, in fact, contain the POLLERR bit (and almost all the other POLLxxx bits as well), but only by chance. This patch fixes code to return a proper bit mask. Credit goes to Markus Elfring for pointing out the suspicious signed/unsigned mismatch. Reported-by: Markus Elfring <elfring@users.sourceforge.net> igned-off-by: Richard Cochran <richardcochran@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Julia Lawall <julia.lawall@lip6.fr> Link: http://lkml.kernel.org/r/1450819198-17420-1-git-send-email-richardcochran@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
447 lines
8.4 KiB
C
447 lines
8.4 KiB
C
/*
|
|
* posix-clock.c - support for dynamic clock devices
|
|
*
|
|
* Copyright (C) 2010 OMICRON electronics GmbH
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
#include <linux/device.h>
|
|
#include <linux/export.h>
|
|
#include <linux/file.h>
|
|
#include <linux/posix-clock.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
static void delete_clock(struct kref *kref);
|
|
|
|
/*
|
|
* Returns NULL if the posix_clock instance attached to 'fp' is old and stale.
|
|
*/
|
|
static struct posix_clock *get_posix_clock(struct file *fp)
|
|
{
|
|
struct posix_clock *clk = fp->private_data;
|
|
|
|
down_read(&clk->rwsem);
|
|
|
|
if (!clk->zombie)
|
|
return clk;
|
|
|
|
up_read(&clk->rwsem);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void put_posix_clock(struct posix_clock *clk)
|
|
{
|
|
up_read(&clk->rwsem);
|
|
}
|
|
|
|
static ssize_t posix_clock_read(struct file *fp, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
int err = -EINVAL;
|
|
|
|
if (!clk)
|
|
return -ENODEV;
|
|
|
|
if (clk->ops.read)
|
|
err = clk->ops.read(clk, fp->f_flags, buf, count);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return err;
|
|
}
|
|
|
|
static unsigned int posix_clock_poll(struct file *fp, poll_table *wait)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
unsigned int result = 0;
|
|
|
|
if (!clk)
|
|
return POLLERR;
|
|
|
|
if (clk->ops.poll)
|
|
result = clk->ops.poll(clk, fp, wait);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int posix_clock_fasync(int fd, struct file *fp, int on)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
int err = 0;
|
|
|
|
if (!clk)
|
|
return -ENODEV;
|
|
|
|
if (clk->ops.fasync)
|
|
err = clk->ops.fasync(clk, fd, fp, on);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int posix_clock_mmap(struct file *fp, struct vm_area_struct *vma)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
int err = -ENODEV;
|
|
|
|
if (!clk)
|
|
return -ENODEV;
|
|
|
|
if (clk->ops.mmap)
|
|
err = clk->ops.mmap(clk, vma);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return err;
|
|
}
|
|
|
|
static long posix_clock_ioctl(struct file *fp,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
int err = -ENOTTY;
|
|
|
|
if (!clk)
|
|
return -ENODEV;
|
|
|
|
if (clk->ops.ioctl)
|
|
err = clk->ops.ioctl(clk, cmd, arg);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static long posix_clock_compat_ioctl(struct file *fp,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct posix_clock *clk = get_posix_clock(fp);
|
|
int err = -ENOTTY;
|
|
|
|
if (!clk)
|
|
return -ENODEV;
|
|
|
|
if (clk->ops.ioctl)
|
|
err = clk->ops.ioctl(clk, cmd, arg);
|
|
|
|
put_posix_clock(clk);
|
|
|
|
return err;
|
|
}
|
|
#endif
|
|
|
|
static int posix_clock_open(struct inode *inode, struct file *fp)
|
|
{
|
|
int err;
|
|
struct posix_clock *clk =
|
|
container_of(inode->i_cdev, struct posix_clock, cdev);
|
|
|
|
down_read(&clk->rwsem);
|
|
|
|
if (clk->zombie) {
|
|
err = -ENODEV;
|
|
goto out;
|
|
}
|
|
if (clk->ops.open)
|
|
err = clk->ops.open(clk, fp->f_mode);
|
|
else
|
|
err = 0;
|
|
|
|
if (!err) {
|
|
kref_get(&clk->kref);
|
|
fp->private_data = clk;
|
|
}
|
|
out:
|
|
up_read(&clk->rwsem);
|
|
return err;
|
|
}
|
|
|
|
static int posix_clock_release(struct inode *inode, struct file *fp)
|
|
{
|
|
struct posix_clock *clk = fp->private_data;
|
|
int err = 0;
|
|
|
|
if (clk->ops.release)
|
|
err = clk->ops.release(clk);
|
|
|
|
kref_put(&clk->kref, delete_clock);
|
|
|
|
fp->private_data = NULL;
|
|
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations posix_clock_file_operations = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.read = posix_clock_read,
|
|
.poll = posix_clock_poll,
|
|
.unlocked_ioctl = posix_clock_ioctl,
|
|
.open = posix_clock_open,
|
|
.release = posix_clock_release,
|
|
.fasync = posix_clock_fasync,
|
|
.mmap = posix_clock_mmap,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = posix_clock_compat_ioctl,
|
|
#endif
|
|
};
|
|
|
|
int posix_clock_register(struct posix_clock *clk, dev_t devid)
|
|
{
|
|
int err;
|
|
|
|
kref_init(&clk->kref);
|
|
init_rwsem(&clk->rwsem);
|
|
|
|
cdev_init(&clk->cdev, &posix_clock_file_operations);
|
|
clk->cdev.owner = clk->ops.owner;
|
|
err = cdev_add(&clk->cdev, devid, 1);
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(posix_clock_register);
|
|
|
|
static void delete_clock(struct kref *kref)
|
|
{
|
|
struct posix_clock *clk = container_of(kref, struct posix_clock, kref);
|
|
|
|
if (clk->release)
|
|
clk->release(clk);
|
|
}
|
|
|
|
void posix_clock_unregister(struct posix_clock *clk)
|
|
{
|
|
cdev_del(&clk->cdev);
|
|
|
|
down_write(&clk->rwsem);
|
|
clk->zombie = true;
|
|
up_write(&clk->rwsem);
|
|
|
|
kref_put(&clk->kref, delete_clock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(posix_clock_unregister);
|
|
|
|
struct posix_clock_desc {
|
|
struct file *fp;
|
|
struct posix_clock *clk;
|
|
};
|
|
|
|
static int get_clock_desc(const clockid_t id, struct posix_clock_desc *cd)
|
|
{
|
|
struct file *fp = fget(CLOCKID_TO_FD(id));
|
|
int err = -EINVAL;
|
|
|
|
if (!fp)
|
|
return err;
|
|
|
|
if (fp->f_op->open != posix_clock_open || !fp->private_data)
|
|
goto out;
|
|
|
|
cd->fp = fp;
|
|
cd->clk = get_posix_clock(fp);
|
|
|
|
err = cd->clk ? 0 : -ENODEV;
|
|
out:
|
|
if (err)
|
|
fput(fp);
|
|
return err;
|
|
}
|
|
|
|
static void put_clock_desc(struct posix_clock_desc *cd)
|
|
{
|
|
put_posix_clock(cd->clk);
|
|
fput(cd->fp);
|
|
}
|
|
|
|
static int pc_clock_adjtime(clockid_t id, struct timex *tx)
|
|
{
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if ((cd.fp->f_mode & FMODE_WRITE) == 0) {
|
|
err = -EACCES;
|
|
goto out;
|
|
}
|
|
|
|
if (cd.clk->ops.clock_adjtime)
|
|
err = cd.clk->ops.clock_adjtime(cd.clk, tx);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
out:
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pc_clock_gettime(clockid_t id, struct timespec *ts)
|
|
{
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if (cd.clk->ops.clock_gettime)
|
|
err = cd.clk->ops.clock_gettime(cd.clk, ts);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pc_clock_getres(clockid_t id, struct timespec *ts)
|
|
{
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if (cd.clk->ops.clock_getres)
|
|
err = cd.clk->ops.clock_getres(cd.clk, ts);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pc_clock_settime(clockid_t id, const struct timespec *ts)
|
|
{
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if ((cd.fp->f_mode & FMODE_WRITE) == 0) {
|
|
err = -EACCES;
|
|
goto out;
|
|
}
|
|
|
|
if (cd.clk->ops.clock_settime)
|
|
err = cd.clk->ops.clock_settime(cd.clk, ts);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
out:
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pc_timer_create(struct k_itimer *kit)
|
|
{
|
|
clockid_t id = kit->it_clock;
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if (cd.clk->ops.timer_create)
|
|
err = cd.clk->ops.timer_create(cd.clk, kit);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int pc_timer_delete(struct k_itimer *kit)
|
|
{
|
|
clockid_t id = kit->it_clock;
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if (cd.clk->ops.timer_delete)
|
|
err = cd.clk->ops.timer_delete(cd.clk, kit);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
static void pc_timer_gettime(struct k_itimer *kit, struct itimerspec *ts)
|
|
{
|
|
clockid_t id = kit->it_clock;
|
|
struct posix_clock_desc cd;
|
|
|
|
if (get_clock_desc(id, &cd))
|
|
return;
|
|
|
|
if (cd.clk->ops.timer_gettime)
|
|
cd.clk->ops.timer_gettime(cd.clk, kit, ts);
|
|
|
|
put_clock_desc(&cd);
|
|
}
|
|
|
|
static int pc_timer_settime(struct k_itimer *kit, int flags,
|
|
struct itimerspec *ts, struct itimerspec *old)
|
|
{
|
|
clockid_t id = kit->it_clock;
|
|
struct posix_clock_desc cd;
|
|
int err;
|
|
|
|
err = get_clock_desc(id, &cd);
|
|
if (err)
|
|
return err;
|
|
|
|
if (cd.clk->ops.timer_settime)
|
|
err = cd.clk->ops.timer_settime(cd.clk, kit, flags, ts, old);
|
|
else
|
|
err = -EOPNOTSUPP;
|
|
|
|
put_clock_desc(&cd);
|
|
|
|
return err;
|
|
}
|
|
|
|
struct k_clock clock_posix_dynamic = {
|
|
.clock_getres = pc_clock_getres,
|
|
.clock_set = pc_clock_settime,
|
|
.clock_get = pc_clock_gettime,
|
|
.clock_adj = pc_clock_adjtime,
|
|
.timer_create = pc_timer_create,
|
|
.timer_set = pc_timer_settime,
|
|
.timer_del = pc_timer_delete,
|
|
.timer_get = pc_timer_gettime,
|
|
};
|