From: Kirill Tkhai <ktk...@odin.com> It's the similar to VZCTL_VE_CONFIGURE ioctl in PCS6.
Note: max_write_len is __NEW_UTS_LEN + 1, because I want to allow echo ... > ve.os_release, which adds trailing '\n' to the string (see man echo for details). Extra symbol will be cut in ve_os_release_write(). https://jira.sw.ru/browse/PSBM-32273 Signed-off-by: Kirill Tkhai <ktk...@odin.com> Signed-off-by: Stanislav Kinsburskiy <skinsbur...@virtuozzo.com> (cherry picked from vz8 commit d9c541f7a5f43f1f39df07f3b50d2704c3f2fe9b) Signed-off-by: Andrey Zhadchenko <andrey.zhadche...@virtuozzo.com> --- kernel/ve/ve.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) diff --git a/kernel/ve/ve.c b/kernel/ve/ve.c index 751f43f..03eb636 100644 --- a/kernel/ve/ve.c +++ b/kernel/ve/ve.c @@ -647,6 +647,55 @@ static u64 ve_netns_avail_nr_read(struct cgroup_subsys_state *css, struct cftype return atomic_read(&css_to_ve(css)->netns_avail_nr); } +static int ve_os_release_read(struct seq_file *sf, void *v) +{ + struct cgroup_subsys_state *css = seq_css(sf); + struct ve_struct *ve = css_to_ve(css); + int ret = 0; + + down_read(&ve->op_sem); + + if (!ve->ve_ns) { + ret = -ENOENT; + goto up_opsem; + } + + down_read(&uts_sem); + seq_puts(sf, ve->ve_ns->uts_ns->name.release); + seq_putc(sf, '\n'); + up_read(&uts_sem); +up_opsem: + up_read(&ve->op_sem); + + return ret; +} + +static ssize_t ve_os_release_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct cgroup_subsys_state *css = of_css(of); + struct ve_struct *ve = css_to_ve(css); + char *release; + int ret = 0; + + down_read(&ve->op_sem); + + if (!ve->ve_ns) { + ret = -ENOENT; + goto up_opsem; + } + + down_write(&uts_sem); + release = ve->ve_ns->uts_ns->name.release; + strncpy(release, buf, __NEW_UTS_LEN); + release[__NEW_UTS_LEN] = '\0'; + up_write(&uts_sem); +up_opsem: + up_read(&ve->op_sem); + + return ret ? ret : nbytes; +} + static struct cftype ve_cftypes[] = { { @@ -683,6 +732,13 @@ static u64 ve_netns_avail_nr_read(struct cgroup_subsys_state *css, struct cftype .name = "netns_avail_nr", .read_u64 = ve_netns_avail_nr_read, }, + { + .name = "os_release", + .max_write_len = __NEW_UTS_LEN + 1, + .flags = CFTYPE_NOT_ON_ROOT, + .seq_show = ve_os_release_read, + .write = ve_os_release_write, + }, { } }; -- 1.8.3.1 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
