proc: implement proc_single_file_operations

Currently many /proc/pid files use a crufty precursor to the current seq_file
api, and they don't have direct access to the pid_namespace or the pid of for
which they are displaying data.

So implement proc_single_file_operations to make the seq_file routines easy to
use, and to give access to the full state of the pid of we are displaying data
for.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric W. Biederman 2008-02-08 04:18:30 -08:00 committed by Linus Torvalds
parent 94413d8807
commit be614086a4
2 changed files with 46 additions and 0 deletions

View File

@ -121,6 +121,10 @@ struct pid_entry {
NOD(NAME, (S_IFREG|(MODE)), \
NULL, &proc_info_file_operations, \
{ .proc_read = &proc_##OTYPE } )
#define ONE(NAME, MODE, OTYPE) \
NOD(NAME, (S_IFREG|(MODE)), \
NULL, &proc_single_file_operations, \
{ .proc_show = &proc_##OTYPE } )
int maps_protect;
EXPORT_SYMBOL(maps_protect);
@ -658,6 +662,45 @@ static const struct file_operations proc_info_file_operations = {
.read = proc_info_read,
};
static int proc_single_show(struct seq_file *m, void *v)
{
struct inode *inode = m->private;
struct pid_namespace *ns;
struct pid *pid;
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;
ret = PROC_I(inode)->op.proc_show(m, ns, pid, task);
put_task_struct(task);
return ret;
}
static int proc_single_open(struct inode *inode, struct file *filp)
{
int ret;
ret = single_open(filp, proc_single_show, NULL);
if (!ret) {
struct seq_file *m = filp->private_data;
m->private = inode;
}
return ret;
}
static const struct file_operations proc_single_file_operations = {
.open = proc_single_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int mem_open(struct inode* inode, struct file* file)
{
file->private_data = (void*)((long)current->self_exec_id);

View File

@ -262,6 +262,9 @@ extern void kclist_add(struct kcore_list *, void *, size_t);
union proc_op {
int (*proc_get_link)(struct inode *, struct dentry **, struct vfsmount **);
int (*proc_read)(struct task_struct *task, char *page);
int (*proc_show)(struct seq_file *m,
struct pid_namespace *ns, struct pid *pid,
struct task_struct *task);
};
struct proc_inode {