The bug is we're not able to remove the device from blkio cgroup's
per-device control files if it gets unplugged.
To reproduce the bug:
# mount -t cgroup -o blkio xxx /cgroup
# cd /cgroup
# echo "8:0 1000" > blkio.throttle.read_bps_device
# unplug the device
# cat blkio.throttle.read_bps_device
8:0 1000
# echo "8:0 0" > blkio.throttle.read_bps_device
-bash: echo: write error: No such device
After patching, the device removal will succeed.
Thanks for the comments of Paul, Zefan, and Vivek.
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
{
char *s[4], *p, *major_s = NULL, *minor_s = NULL;
int ret;
{
char *s[4], *p, *major_s = NULL, *minor_s = NULL;
int ret;
- unsigned long major, minor, temp;
+ unsigned long major, minor;
dev = MKDEV(major, minor);
dev = MKDEV(major, minor);
- ret = blkio_check_dev_num(dev);
+ ret = strict_strtoull(s[1], 10, &temp);
+ /* For rule removal, do not check for device presence. */
+ if (temp) {
+ ret = blkio_check_dev_num(dev);
+ if (ret)
+ return ret;
+ }
- if (s[1] == NULL)
- return -EINVAL;
switch (plid) {
case BLKIO_POLICY_PROP:
switch (plid) {
case BLKIO_POLICY_PROP:
- ret = strict_strtoul(s[1], 10, &temp);
- if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) ||
- temp > BLKIO_WEIGHT_MAX)
+ if ((temp < BLKIO_WEIGHT_MIN && temp > 0) ||
+ temp > BLKIO_WEIGHT_MAX)
return -EINVAL;
newpn->plid = plid;
return -EINVAL;
newpn->plid = plid;
switch(fileid) {
case BLKIO_THROTL_read_bps_device:
case BLKIO_THROTL_write_bps_device:
switch(fileid) {
case BLKIO_THROTL_read_bps_device:
case BLKIO_THROTL_write_bps_device:
- ret = strict_strtoull(s[1], 10, &bps);
- if (ret)
- return -EINVAL;
-
newpn->plid = plid;
newpn->fileid = fileid;
newpn->plid = plid;
newpn->fileid = fileid;
break;
case BLKIO_THROTL_read_iops_device:
case BLKIO_THROTL_write_iops_device:
break;
case BLKIO_THROTL_read_iops_device:
case BLKIO_THROTL_write_iops_device:
- ret = strict_strtoull(s[1], 10, &iops);
- if (ret)
- return -EINVAL;
-
- if (iops > THROTL_IOPS_MAX)
+ if (temp > THROTL_IOPS_MAX)
return -EINVAL;
newpn->plid = plid;
newpn->fileid = fileid;
return -EINVAL;
newpn->plid = plid;
newpn->fileid = fileid;
- newpn->val.iops = (unsigned int)iops;
+ newpn->val.iops = (unsigned int)temp;