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Commit 0226f492 authored by Al Viro's avatar Al Viro
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vfs: take /proc/*/mounts and friends to fs/proc_namespace.c 

rationale: that stuff is far tighter bound to fs/namespace.c than to
the guts of procfs proper.
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 3a2393d7
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Inline Side-by-side
Showing with 368 additions and 351 deletions
fs/Makefile
View file @ 0226f492
......@@ -19,6 +19,8 @@ else
obj-y += no-block.o
endif
obj-$(CONFIG_PROC_FS) += proc_namespace.o
obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o
obj-y += notify/
obj-$(CONFIG_EPOLL) += eventpoll.o
......
fs/mount.h
View file @ 0226f492
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/poll.h>
struct mnt_namespace {
atomic_t count;
struct vfsmount * root;
struct list_head list;
wait_queue_head_t poll;
int event;
};
struct mnt_pcp {
int mnt_count;
......@@ -49,3 +59,17 @@ static inline int mnt_has_parent(struct mount *mnt)
}
extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *, int);
static inline void get_mnt_ns(struct mnt_namespace *ns)
{
atomic_inc(&ns->count);
}
struct proc_mounts {
struct seq_file m; /* must be the first element */
struct mnt_namespace *ns;
struct path root;
int (*show)(struct seq_file *, struct vfsmount *);
};
extern const struct seq_operations mounts_op;
fs/namespace.c
View file @ 0226f492
......@@ -898,10 +898,10 @@ void replace_mount_options(struct super_block *sb, char *options)
EXPORT_SYMBOL(replace_mount_options);
#ifdef CONFIG_PROC_FS
/* iterator */
/* iterator; we want it to have access to namespace_sem, thus here... */
static void *m_start(struct seq_file *m, loff_t *pos)
{
struct proc_mounts *p = m->private;
struct proc_mounts *p = container_of(m, struct proc_mounts, m);
down_read(&namespace_sem);
return seq_list_start(&p->ns->list, *pos);
......@@ -909,7 +909,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
static void *m_next(struct seq_file *m, void *v, loff_t *pos)
{
struct proc_mounts *p = m->private;
struct proc_mounts *p = container_of(m, struct proc_mounts, m);
return seq_list_next(v, &p->ns->list, pos);
}
......@@ -919,222 +919,18 @@ static void m_stop(struct seq_file *m, void *v)
up_read(&namespace_sem);
}
int mnt_had_events(struct proc_mounts *p)
{
struct mnt_namespace *ns = p->ns;
int res = 0;
br_read_lock(vfsmount_lock);
if (p->m.poll_event != ns->event) {
p->m.poll_event = ns->event;
res = 1;
}
br_read_unlock(vfsmount_lock);
return res;
}
struct proc_fs_info {
int flag;
const char *str;
};
static int show_sb_opts(struct seq_file *m, struct super_block *sb)
{
static const struct proc_fs_info fs_info[] = {
{ MS_SYNCHRONOUS, ",sync" },
{ MS_DIRSYNC, ",dirsync" },
{ MS_MANDLOCK, ",mand" },
{ 0, NULL }
};
const struct proc_fs_info *fs_infop;
for (fs_infop = fs_info; fs_infop->flag; fs_infop++) {
if (sb->s_flags & fs_infop->flag)
seq_puts(m, fs_infop->str);
}
return security_sb_show_options(m, sb);
}
static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
{
static const struct proc_fs_info mnt_info[] = {
{ MNT_NOSUID, ",nosuid" },
{ MNT_NODEV, ",nodev" },
{ MNT_NOEXEC, ",noexec" },
{ MNT_NOATIME, ",noatime" },
{ MNT_NODIRATIME, ",nodiratime" },
{ MNT_RELATIME, ",relatime" },
{ 0, NULL }
};
const struct proc_fs_info *fs_infop;
for (fs_infop = mnt_info; fs_infop->flag; fs_infop++) {
if (mnt->mnt_flags & fs_infop->flag)
seq_puts(m, fs_infop->str);
}
}
static void show_type(struct seq_file *m, struct super_block *sb)
{
mangle(m, sb->s_type->name);
if (sb->s_subtype && sb->s_subtype[0]) {
seq_putc(m, '.');
mangle(m, sb->s_subtype);
}
}
static int show_vfsmnt(struct seq_file *m, void *v)
static int m_show(struct seq_file *m, void *v)
{
struct proc_mounts *p = container_of(m, struct proc_mounts, m);
struct mount *r = list_entry(v, struct mount, mnt_list);
struct vfsmount *mnt = &r->mnt;
int err = 0;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
if (mnt->mnt_sb->s_op->show_devname) {
err = mnt->mnt_sb->s_op->show_devname(m, mnt);
if (err)
goto out;
} else {
mangle(m, r->mnt_devname ? r->mnt_devname : "none");
}
seq_putc(m, ' ');
seq_path(m, &mnt_path, " \t\n\\");
seq_putc(m, ' ');
show_type(m, mnt->mnt_sb);
seq_puts(m, __mnt_is_readonly(mnt) ? " ro" : " rw");
err = show_sb_opts(m, mnt->mnt_sb);
if (err)
goto out;
show_mnt_opts(m, mnt);
if (mnt->mnt_sb->s_op->show_options)
err = mnt->mnt_sb->s_op->show_options(m, mnt);
seq_puts(m, " 0 0\n");
out:
return err;
return p->show(m, &r->mnt);
}
const struct seq_operations mounts_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
.show = show_vfsmnt
};
static int show_mountinfo(struct seq_file *m, void *v)
{
struct proc_mounts *p = m->private;
struct mount *r = list_entry(v, struct mount, mnt_list);
struct vfsmount *mnt = &r->mnt;
struct super_block *sb = mnt->mnt_sb;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
struct path root = p->root;
int err = 0;
seq_printf(m, "%i %i %u:%u ", r->mnt_id, r->mnt_parent->mnt_id,
MAJOR(sb->s_dev), MINOR(sb->s_dev));
if (sb->s_op->show_path)
err = sb->s_op->show_path(m, mnt);
else
seq_dentry(m, mnt->mnt_root, " \t\n\\");
if (err)
goto out;
seq_putc(m, ' ');
/* mountpoints outside of chroot jail will give SEQ_SKIP on this */
err = seq_path_root(m, &mnt_path, &root, " \t\n\\");
if (err)
goto out;
seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : " rw");
show_mnt_opts(m, mnt);
/* Tagged fields ("foo:X" or "bar") */
if (IS_MNT_SHARED(r))
seq_printf(m, " shared:%i", r->mnt_group_id);
if (IS_MNT_SLAVE(r)) {
int master = r->mnt_master->mnt_group_id;
int dom = get_dominating_id(r, &p->root);
seq_printf(m, " master:%i", master);
if (dom && dom != master)
seq_printf(m, " propagate_from:%i", dom);
}
if (IS_MNT_UNBINDABLE(r))
seq_puts(m, " unbindable");
/* Filesystem specific data */
seq_puts(m, " - ");
show_type(m, sb);
seq_putc(m, ' ');
if (sb->s_op->show_devname)
err = sb->s_op->show_devname(m, mnt);
else
mangle(m, r->mnt_devname ? r->mnt_devname : "none");
if (err)
goto out;
seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw");
err = show_sb_opts(m, sb);
if (err)
goto out;
if (sb->s_op->show_options)
err = sb->s_op->show_options(m, mnt);
seq_putc(m, '\n');
out:
return err;
}
const struct seq_operations mountinfo_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
.show = show_mountinfo,
};
static int show_vfsstat(struct seq_file *m, void *v)
{
struct mount *r = list_entry(v, struct mount, mnt_list);
struct vfsmount *mnt = &r->mnt;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
int err = 0;
/* device */
if (mnt->mnt_sb->s_op->show_devname) {
seq_puts(m, "device ");
err = mnt->mnt_sb->s_op->show_devname(m, mnt);
} else {
if (r->mnt_devname) {
seq_puts(m, "device ");
mangle(m, r->mnt_devname);
} else
seq_puts(m, "no device");
}
/* mount point */
seq_puts(m, " mounted on ");
seq_path(m, &mnt_path, " \t\n\\");
seq_putc(m, ' ');
/* file system type */
seq_puts(m, "with fstype ");
show_type(m, mnt->mnt_sb);
/* optional statistics */
if (mnt->mnt_sb->s_op->show_stats) {
seq_putc(m, ' ');
if (!err)
err = mnt->mnt_sb->s_op->show_stats(m, mnt);
}
seq_putc(m, '\n');
return err;
}
const struct seq_operations mountstats_op = {
.start = m_start,
.next = m_next,
.stop = m_stop,
.show = show_vfsstat,
.show = m_show,
};
#endif /* CONFIG_PROC_FS */
......
fs/proc/base.c
View file @ 0226f492
......@@ -631,120 +631,6 @@ static const struct inode_operations proc_def_inode_operations = {
.setattr = proc_setattr,
};
static int mounts_open_common(struct inode *inode, struct file *file,
const struct seq_operations *op)
{
struct task_struct *task = get_proc_task(inode);
struct nsproxy *nsp;
struct mnt_namespace *ns = NULL;
struct path root;
struct proc_mounts *p;
int ret = -EINVAL;
if (task) {
rcu_read_lock();
nsp = task_nsproxy(task);
if (nsp) {
ns = nsp->mnt_ns;
if (ns)
get_mnt_ns(ns);
}
rcu_read_unlock();
if (ns && get_task_root(task, &root) == 0)
ret = 0;
put_task_struct(task);
}
if (!ns)
goto err;
if (ret)
goto err_put_ns;
ret = -ENOMEM;
p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
if (!p)
goto err_put_path;
file->private_data = &p->m;
ret = seq_open(file, op);
if (ret)
goto err_free;
p->m.private = p;
p->ns = ns;
p->root = root;
p->m.poll_event = ns->event;
return 0;
err_free:
kfree(p);
err_put_path:
path_put(&root);
err_put_ns:
put_mnt_ns(ns);
err:
return ret;
}
static int mounts_release(struct inode *inode, struct file *file)
{
struct proc_mounts *p = file->private_data;
path_put(&p->root);
put_mnt_ns(p->ns);
return seq_release(inode, file);
}
static unsigned mounts_poll(struct file *file, poll_table *wait)
{
struct proc_mounts *p = file->private_data;
unsigned res = POLLIN | POLLRDNORM;
poll_wait(file, &p->ns->poll, wait);
if (mnt_had_events(p))
res |= POLLERR | POLLPRI;
return res;
}
static int mounts_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, &mounts_op);
}
static const struct file_operations proc_mounts_operations = {
.open = mounts_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
.poll = mounts_poll,
};
static int mountinfo_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, &mountinfo_op);
}
static const struct file_operations proc_mountinfo_operations = {
.open = mountinfo_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
.poll = mounts_poll,
};
static int mountstats_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, &mountstats_op);
}
static const struct file_operations proc_mountstats_operations = {
.open = mountstats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
};
#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
static ssize_t proc_info_read(struct file * file, char __user * buf,
......
fs/proc_namespace.c 0 → 100644
View file @ 0226f492
/*
* fs/proc_namespace.c - handling of /proc/<pid>/{mounts,mountinfo,mountstats}
*
* In fact, that's a piece of procfs; it's *almost* isolated from
* the rest of fs/proc, but has rather close relationships with
* fs/namespace.c, thus here instead of fs/proc
*
*/
#include <linux/mnt_namespace.h>
#include <linux/nsproxy.h>
#include <linux/security.h>
#include <linux/fs_struct.h>
#include "proc/internal.h" /* only for get_proc_task() in ->open() */
#include "pnode.h"
#include "internal.h"
static unsigned mounts_poll(struct file *file, poll_table *wait)
{
struct proc_mounts *p = file->private_data;
struct mnt_namespace *ns = p->ns;
unsigned res = POLLIN | POLLRDNORM;
poll_wait(file, &p->ns->poll, wait);
br_read_lock(vfsmount_lock);
if (p->m.poll_event != ns->event) {
p->m.poll_event = ns->event;
res |= POLLERR | POLLPRI;
}
br_read_unlock(vfsmount_lock);
return res;
}
struct proc_fs_info {
int flag;
const char *str;
};
static int show_sb_opts(struct seq_file *m, struct super_block *sb)
{
static const struct proc_fs_info fs_info[] = {
{ MS_SYNCHRONOUS, ",sync" },
{ MS_DIRSYNC, ",dirsync" },
{ MS_MANDLOCK, ",mand" },
{ 0, NULL }
};
const struct proc_fs_info *fs_infop;
for (fs_infop = fs_info; fs_infop->flag; fs_infop++) {
if (sb->s_flags & fs_infop->flag)
seq_puts(m, fs_infop->str);
}
return security_sb_show_options(m, sb);
}
static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
{
static const struct proc_fs_info mnt_info[] = {
{ MNT_NOSUID, ",nosuid" },
{ MNT_NODEV, ",nodev" },
{ MNT_NOEXEC, ",noexec" },
{ MNT_NOATIME, ",noatime" },
{ MNT_NODIRATIME, ",nodiratime" },
{ MNT_RELATIME, ",relatime" },
{ 0, NULL }
};
const struct proc_fs_info *fs_infop;
for (fs_infop = mnt_info; fs_infop->flag; fs_infop++) {
if (mnt->mnt_flags & fs_infop->flag)
seq_puts(m, fs_infop->str);
}
}
static inline void mangle(struct seq_file *m, const char *s)
{
seq_escape(m, s, " \t\n\\");
}
static void show_type(struct seq_file *m, struct super_block *sb)
{
mangle(m, sb->s_type->name);
if (sb->s_subtype && sb->s_subtype[0]) {
seq_putc(m, '.');
mangle(m, sb->s_subtype);
}
}
static int show_vfsmnt(struct seq_file *m, struct vfsmount *mnt)
{
struct mount *r = real_mount(mnt);
int err = 0;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
if (mnt->mnt_sb->s_op->show_devname) {
err = mnt->mnt_sb->s_op->show_devname(m, mnt);
if (err)
goto out;
} else {
mangle(m, r->mnt_devname ? r->mnt_devname : "none");
}
seq_putc(m, ' ');
seq_path(m, &mnt_path, " \t\n\\");
seq_putc(m, ' ');
show_type(m, mnt->mnt_sb);
seq_puts(m, __mnt_is_readonly(mnt) ? " ro" : " rw");
err = show_sb_opts(m, mnt->mnt_sb);
if (err)
goto out;
show_mnt_opts(m, mnt);
if (mnt->mnt_sb->s_op->show_options)
err = mnt->mnt_sb->s_op->show_options(m, mnt);
seq_puts(m, " 0 0\n");
out:
return err;
}
static int show_mountinfo(struct seq_file *m, struct vfsmount *mnt)
{
struct proc_mounts *p = m->private;
struct mount *r = real_mount(mnt);
struct super_block *sb = mnt->mnt_sb;
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
struct path root = p->root;
int err = 0;
seq_printf(m, "%i %i %u:%u ", r->mnt_id, r->mnt_parent->mnt_id,
MAJOR(sb->s_dev), MINOR(sb->s_dev));
if (sb->s_op->show_path)
err = sb->s_op->show_path(m, mnt);
else
seq_dentry(m, mnt->mnt_root, " \t\n\\");
if (err)
goto out;
seq_putc(m, ' ');
/* mountpoints outside of chroot jail will give SEQ_SKIP on this */
err = seq_path_root(m, &mnt_path, &root, " \t\n\\");
if (err)
goto out;
seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : " rw");
show_mnt_opts(m, mnt);
/* Tagged fields ("foo:X" or "bar") */
if (IS_MNT_SHARED(r))
seq_printf(m, " shared:%i", r->mnt_group_id);
if (IS_MNT_SLAVE(r)) {
int master = r->mnt_master->mnt_group_id;
int dom = get_dominating_id(r, &p->root);
seq_printf(m, " master:%i", master);
if (dom && dom != master)
seq_printf(m, " propagate_from:%i", dom);
}
if (IS_MNT_UNBINDABLE(r))
seq_puts(m, " unbindable");
/* Filesystem specific data */
seq_puts(m, " - ");
show_type(m, sb);
seq_putc(m, ' ');
if (sb->s_op->show_devname)
err = sb->s_op->show_devname(m, mnt);
else
mangle(m, r->mnt_devname ? r->mnt_devname : "none");
if (err)
goto out;
seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw");
err = show_sb_opts(m, sb);
if (err)
goto out;
if (sb->s_op->show_options)
err = sb->s_op->show_options(m, mnt);
seq_putc(m, '\n');
out:
return err;
}
static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt)
{
struct mount *r = real_mount(mnt);
struct path mnt_path = { .dentry = mnt->mnt_root, .mnt = mnt };
int err = 0;
/* device */
if (mnt->mnt_sb->s_op->show_devname) {
seq_puts(m, "device ");
err = mnt->mnt_sb->s_op->show_devname(m, mnt);
} else {
if (r->mnt_devname) {
seq_puts(m, "device ");
mangle(m, r->mnt_devname);
} else
seq_puts(m, "no device");
}
/* mount point */
seq_puts(m, " mounted on ");
seq_path(m, &mnt_path, " \t\n\\");
seq_putc(m, ' ');
/* file system type */
seq_puts(m, "with fstype ");
show_type(m, mnt->mnt_sb);
/* optional statistics */
if (mnt->mnt_sb->s_op->show_stats) {
seq_putc(m, ' ');
if (!err)
err = mnt->mnt_sb->s_op->show_stats(m, mnt);
}
seq_putc(m, '\n');
return err;
}
static int mounts_open_common(struct inode *inode, struct file *file,
int (*show)(struct seq_file *, struct vfsmount *))
{
struct task_struct *task = get_proc_task(inode);
struct nsproxy *nsp;
struct mnt_namespace *ns = NULL;
struct path root;
struct proc_mounts *p;
int ret = -EINVAL;
if (!task)
goto err;
rcu_read_lock();
nsp = task_nsproxy(task);
if (!nsp) {
rcu_read_unlock();
put_task_struct(task);
goto err;
}
ns = nsp->mnt_ns;
if (!ns) {
rcu_read_unlock();
put_task_struct(task);
goto err;
}
get_mnt_ns(ns);
rcu_read_unlock();
task_lock(task);
if (!task->fs) {
task_unlock(task);
put_task_struct(task);
ret = -ENOENT;
goto err_put_ns;
}
get_fs_root(task->fs, &root);
task_unlock(task);
put_task_struct(task);
ret = -ENOMEM;
p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
if (!p)
goto err_put_path;
file->private_data = &p->m;
ret = seq_open(file, &mounts_op);
if (ret)
goto err_free;
p->m.private = p;
p->ns = ns;
p->root = root;
p->m.poll_event = ns->event;
p->show = show;
return 0;
err_free:
kfree(p);
err_put_path:
path_put(&root);
err_put_ns:
put_mnt_ns(ns);
err:
return ret;
}
static int mounts_release(struct inode *inode, struct file *file)
{
struct proc_mounts *p = file->private_data;
path_put(&p->root);
put_mnt_ns(p->ns);
return seq_release(inode, file);
}
static int mounts_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, show_vfsmnt);
}
static int mountinfo_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, show_mountinfo);
}
static int mountstats_open(struct inode *inode, struct file *file)
{
return mounts_open_common(inode, file, show_vfsstat);
}
const struct file_operations proc_mounts_operations = {
.open = mounts_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
.poll = mounts_poll,
};
const struct file_operations proc_mountinfo_operations = {
.open = mountinfo_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
.poll = mounts_poll,
};
const struct file_operations proc_mountstats_operations = {
.open = mountstats_open,
.read = seq_read,
.llseek = seq_lseek,
.release = mounts_release,
};
include/linux/mnt_namespace.h
View file @ 0226f492
......@@ -2,38 +2,16 @@
#define _NAMESPACE_H_
#ifdef __KERNEL__
#include <linux/path.h>
#include <linux/seq_file.h>
#include <linux/wait.h>
struct mnt_namespace {
atomic_t count;
struct vfsmount * root;
struct list_head list;
wait_queue_head_t poll;
int event;
};
struct proc_mounts {
struct seq_file m; /* must be the first element */
struct mnt_namespace *ns;
struct path root;
};
struct mnt_namespace;
struct fs_struct;
extern struct mnt_namespace *copy_mnt_ns(unsigned long, struct mnt_namespace *,
struct fs_struct *);
extern void put_mnt_ns(struct mnt_namespace *ns);
static inline void get_mnt_ns(struct mnt_namespace *ns)
{
atomic_inc(&ns->count);
}
extern const struct seq_operations mounts_op;
extern const struct seq_operations mountinfo_op;
extern const struct seq_operations mountstats_op;
extern int mnt_had_events(struct proc_mounts *);
extern const struct file_operations proc_mounts_operations;
extern const struct file_operations proc_mountinfo_operations;
extern const struct file_operations proc_mountstats_operations;
#endif
#endif
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