summaryrefslogtreecommitdiffstats
path: root/fs/proc/base.c
diff options
context:
space:
mode:
authorEric W. Biederman <ebiederm@xmission.com>2010-07-10 14:52:49 -0700
committerEric W. Biederman <ebiederm@xmission.com>2012-11-19 03:09:34 -0800
commite656d8a6f7fdf7612d2f5771f0ddfca9487f59d9 (patch)
tree66479ae4b636517e0e54e78b4ec95acadd0aec7a /fs/proc/base.c
parentdd34ad35c32bb3d16789d8d4084aead7e68a7b09 (diff)
downloadlinux-e656d8a6f7fdf7612d2f5771f0ddfca9487f59d9.tar.bz2
procfs: Use the proc generic infrastructure for proc/self.
I had visions at one point of splitting proc into two filesystems. If that had happened proc/self being the the part of proc that actually deals with pids would have been a nice cleanup. As it is proc/self requires a lot of unnecessary infrastructure for a single file. The only user visible change is that a mounted /proc for a pid namespace that is dead now shows a broken proc symlink, instead of being completely invisible. I don't think anyone will notice or care. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Diffstat (limited to 'fs/proc/base.c')
-rw-r--r--fs/proc/base.c154
1 files changed, 2 insertions, 152 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 144a96732dd7..cbe454e94af8 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2237,146 +2237,6 @@ static const struct file_operations proc_coredump_filter_operations = {
};
#endif
-/*
- * /proc/self:
- */
-static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
- int buflen)
-{
- struct pid_namespace *ns = dentry->d_sb->s_fs_info;
- pid_t tgid = task_tgid_nr_ns(current, ns);
- char tmp[PROC_NUMBUF];
- if (!tgid)
- return -ENOENT;
- sprintf(tmp, "%d", tgid);
- return vfs_readlink(dentry,buffer,buflen,tmp);
-}
-
-static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
-{
- struct pid_namespace *ns = dentry->d_sb->s_fs_info;
- pid_t tgid = task_tgid_nr_ns(current, ns);
- char *name = ERR_PTR(-ENOENT);
- if (tgid) {
- /* 11 for max length of signed int in decimal + NULL term */
- name = kmalloc(12, GFP_KERNEL);
- if (!name)
- name = ERR_PTR(-ENOMEM);
- else
- sprintf(name, "%d", tgid);
- }
- nd_set_link(nd, name);
- return NULL;
-}
-
-static void proc_self_put_link(struct dentry *dentry, struct nameidata *nd,
- void *cookie)
-{
- char *s = nd_get_link(nd);
- if (!IS_ERR(s))
- kfree(s);
-}
-
-static const struct inode_operations proc_self_inode_operations = {
- .readlink = proc_self_readlink,
- .follow_link = proc_self_follow_link,
- .put_link = proc_self_put_link,
-};
-
-/*
- * proc base
- *
- * These are the directory entries in the root directory of /proc
- * that properly belong to the /proc filesystem, as they describe
- * describe something that is process related.
- */
-static const struct pid_entry proc_base_stuff[] = {
- NOD("self", S_IFLNK|S_IRWXUGO,
- &proc_self_inode_operations, NULL, {}),
-};
-
-static struct dentry *proc_base_instantiate(struct inode *dir,
- struct dentry *dentry, struct task_struct *task, const void *ptr)
-{
- const struct pid_entry *p = ptr;
- struct inode *inode;
- struct proc_inode *ei;
- struct dentry *error;
-
- /* Allocate the inode */
- error = ERR_PTR(-ENOMEM);
- inode = new_inode(dir->i_sb);
- if (!inode)
- goto out;
-
- /* Initialize the inode */
- ei = PROC_I(inode);
- inode->i_ino = get_next_ino();
- inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-
- /*
- * grab the reference to the task.
- */
- ei->pid = get_task_pid(task, PIDTYPE_PID);
- if (!ei->pid)
- goto out_iput;
-
- inode->i_mode = p->mode;
- if (S_ISDIR(inode->i_mode))
- set_nlink(inode, 2);
- if (S_ISLNK(inode->i_mode))
- inode->i_size = 64;
- if (p->iop)
- inode->i_op = p->iop;
- if (p->fop)
- inode->i_fop = p->fop;
- ei->op = p->op;
- d_add(dentry, inode);
- error = NULL;
-out:
- return error;
-out_iput:
- iput(inode);
- goto out;
-}
-
-static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
-{
- struct dentry *error;
- struct task_struct *task = get_proc_task(dir);
- const struct pid_entry *p, *last;
-
- error = ERR_PTR(-ENOENT);
-
- if (!task)
- goto out_no_task;
-
- /* Lookup the directory entry */
- last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
- for (p = proc_base_stuff; p <= last; p++) {
- if (p->len != dentry->d_name.len)
- continue;
- if (!memcmp(dentry->d_name.name, p->name, p->len))
- break;
- }
- if (p > last)
- goto out;
-
- error = proc_base_instantiate(dir, dentry, task, p);
-
-out:
- put_task_struct(task);
-out_no_task:
- return error;
-}
-
-static int proc_base_fill_cache(struct file *filp, void *dirent,
- filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
-{
- return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
- proc_base_instantiate, task, p);
-}
-
#ifdef CONFIG_TASK_IO_ACCOUNTING
static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
{
@@ -2767,15 +2627,11 @@ out:
struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
{
- struct dentry *result;
+ struct dentry *result = NULL;
struct task_struct *task;
unsigned tgid;
struct pid_namespace *ns;
- result = proc_base_lookup(dir, dentry);
- if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
- goto out;
-
tgid = name_to_int(dentry);
if (tgid == ~0U)
goto out;
@@ -2838,7 +2694,7 @@ retry:
return iter;
}
-#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
+#define TGID_OFFSET (FIRST_PROCESS_ENTRY)
static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
struct tgid_iter iter)
@@ -2872,12 +2728,6 @@ int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
if (!reaper)
goto out_no_task;
- for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
- const struct pid_entry *p = &proc_base_stuff[nr];
- if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
- goto out;
- }
-
ns = filp->f_dentry->d_sb->s_fs_info;
iter.task = NULL;
iter.tgid = filp->f_pos - TGID_OFFSET;