proc: introduce a proc_pid_ns helper
Factor out retrieving the per-sb pid namespaces from the sb private data
into an easier to understand helper.
Suggested-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 1b2ede6..29237ca 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -698,7 +698,7 @@ static bool has_pid_permissions(struct pid_namespace *pid,
static int proc_pid_permission(struct inode *inode, int mask)
{
- struct pid_namespace *pid = inode->i_sb->s_fs_info;
+ struct pid_namespace *pid = proc_pid_ns(inode);
struct task_struct *task;
bool has_perms;
@@ -733,13 +733,11 @@ static const struct inode_operations proc_def_inode_operations = {
static int proc_single_show(struct seq_file *m, void *v)
{
struct inode *inode = m->private;
- struct pid_namespace *ns;
- struct pid *pid;
+ struct pid_namespace *ns = proc_pid_ns(inode);
+ struct pid *pid = proc_pid(inode);
struct task_struct *task;
int ret;
- ns = inode->i_sb->s_fs_info;
- pid = proc_pid(inode);
task = get_pid_task(pid, PIDTYPE_PID);
if (!task)
return -ESRCH;
@@ -1410,7 +1408,7 @@ static const struct file_operations proc_fail_nth_operations = {
static int sched_show(struct seq_file *m, void *v)
{
struct inode *inode = m->private;
- struct pid_namespace *ns = inode->i_sb->s_fs_info;
+ struct pid_namespace *ns = proc_pid_ns(inode);
struct task_struct *p;
p = get_proc_task(inode);
@@ -1782,8 +1780,8 @@ int pid_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
struct inode *inode = d_inode(path->dentry);
+ struct pid_namespace *pid = proc_pid_ns(inode);
struct task_struct *task;
- struct pid_namespace *pid = path->dentry->d_sb->s_fs_info;
generic_fillattr(inode, stat);
@@ -2337,7 +2335,7 @@ static int proc_timers_open(struct inode *inode, struct file *file)
return -ENOMEM;
tp->pid = proc_pid(inode);
- tp->ns = inode->i_sb->s_fs_info;
+ tp->ns = proc_pid_ns(inode);
return 0;
}
@@ -3239,7 +3237,7 @@ static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter ite
int proc_pid_readdir(struct file *file, struct dir_context *ctx)
{
struct tgid_iter iter;
- struct pid_namespace *ns = file_inode(file)->i_sb->s_fs_info;
+ struct pid_namespace *ns = proc_pid_ns(file_inode(file));
loff_t pos = ctx->pos;
if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
@@ -3588,7 +3586,7 @@ static int proc_task_readdir(struct file *file, struct dir_context *ctx)
/* f_version caches the tgid value that the last readdir call couldn't
* return. lseek aka telldir automagically resets f_version to 0.
*/
- ns = inode->i_sb->s_fs_info;
+ ns = proc_pid_ns(inode);
tid = (int)file->f_version;
file->f_version = 0;
for (task = first_tid(proc_pid(inode), tid, ctx->pos - 2, ns);