/* mountpoint management
 *
 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/gfp.h>
#include "internal.h"


static struct dentry *afs_mntpt_lookup(struct inode *dir,
				       struct dentry *dentry,
				       unsigned int flags);
static int afs_mntpt_open(struct inode *inode, struct file *file);
static void afs_mntpt_expiry_timed_out(struct work_struct *work);

const struct file_operations afs_mntpt_file_operations = {
	.open		= afs_mntpt_open,
	.llseek		= noop_llseek,
};

const struct inode_operations afs_mntpt_inode_operations = {
	.lookup		= afs_mntpt_lookup,
	.readlink	= page_readlink,
	.getattr	= afs_getattr,
};

const struct inode_operations afs_autocell_inode_operations = {
	.getattr	= afs_getattr,
};

static LIST_HEAD(afs_vfsmounts);
static DECLARE_DELAYED_WORK(afs_mntpt_expiry_timer, afs_mntpt_expiry_timed_out);

static unsigned long afs_mntpt_expiry_timeout = 10 * 60;

/*
 * check a symbolic link to see whether it actually encodes a mountpoint
 * - sets the AFS_VNODE_MOUNTPOINT flag on the vnode appropriately
 */
int afs_mntpt_check_symlink(struct afs_vnode *vnode, struct key *key)
{
	struct page *page;
	size_t size;
	char *buf;
	int ret;

	_enter("{%x:%u,%u}",
	       vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique);

	/* read the contents of the symlink into the pagecache */
	page = read_cache_page(AFS_VNODE_TO_I(vnode)->i_mapping, 0,
			       afs_page_filler, key);
	if (IS_ERR(page)) {
		ret = PTR_ERR(page);
		goto out;
	}

	ret = -EIO;
	if (PageError(page))
		goto out_free;

	buf = kmap(page);

	/* examine the symlink's contents */
	size = vnode->status.size;
	_debug("symlink to %*.*s", (int) size, (int) size, buf);

	if (size > 2 &&
	    (buf[0] == '%' || buf[0] == '#') &&
	    buf[size - 1] == '.'
	    ) {
		_debug("symlink is a mountpoint");
		spin_lock(&vnode->lock);
		set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags);
		vnode->vfs_inode.i_flags |= S_AUTOMOUNT;
		spin_unlock(&vnode->lock);
	}

	ret = 0;

	kunmap(page);
out_free:
	put_page(page);
out:
	_leave(" = %d", ret);
	return ret;
}

/*
 * no valid lookup procedure on this sort of dir
 */
static struct dentry *afs_mntpt_lookup(struct inode *dir,
				       struct dentry *dentry,
				       unsigned int flags)
{
	_enter("%p,%p{%pd2}", dir, dentry, dentry);
	return ERR_PTR(-EREMOTE);
}

/*
 * no valid open procedure on this sort of dir
 */
static int afs_mntpt_open(struct inode *inode, struct file *file)
{
	_enter("%p,%p{%pD2}", inode, file, file);
	return -EREMOTE;
}

/*
 * create a vfsmount to be automounted
 */
static struct vfsmount *afs_mntpt_do_automount(struct dentry *mntpt)
{
	struct afs_super_info *super;
	struct vfsmount *mnt;
	struct afs_vnode *vnode;
	struct page *page;
	char *devname, *options;
	bool rwpath = false;
	int ret;

	_enter("{%pd}", mntpt);

	BUG_ON(!d_inode(mntpt));

	ret = -ENOMEM;
	devname = (char *) get_zeroed_page(GFP_KERNEL);
	if (!devname)
		goto error_no_devname;

	options = (char *) get_zeroed_page(GFP_KERNEL);
	if (!options)
		goto error_no_options;

	vnode = AFS_FS_I(d_inode(mntpt));
	if (test_bit(AFS_VNODE_PSEUDODIR, &vnode->flags)) {
		/* if the directory is a pseudo directory, use the d_name */
		static const char afs_root_cell[] = ":root.cell.";
		unsigned size = mntpt->d_name.len;

		ret = -ENOENT;
		if (size < 2 || size > AFS_MAXCELLNAME)
			goto error_no_page;

		if (mntpt->d_name.name[0] == '.') {
			devname[0] = '#';
			memcpy(devname + 1, mntpt->d_name.name, size - 1);
			memcpy(devname + size, afs_root_cell,
			       sizeof(afs_root_cell));
			rwpath = true;
		} else {
			devname[0] = '%';
			memcpy(devname + 1, mntpt->d_name.name, size);
			memcpy(devname + size + 1, afs_root_cell,
			       sizeof(afs_root_cell));
		}
	} else {
		/* read the contents of the AFS special symlink */
		loff_t size = i_size_read(d_inode(mntpt));
		char *buf;

		ret = -EINVAL;
		if (size > PAGE_SIZE - 1)
			goto error_no_page;

		page = read_mapping_page(d_inode(mntpt)->i_mapping, 0, NULL);
		if (IS_ERR(page)) {
			ret = PTR_ERR(page);
			goto error_no_page;
		}

		ret = -EIO;
		if (PageError(page))
			goto error;

		buf = kmap_atomic(page);
		memcpy(devname, buf, size);
		kunmap_atomic(buf);
		put_page(page);
		page = NULL;
	}

	/* work out what options we want */
	super = AFS_FS_S(mntpt->d_sb);
	memcpy(options, "cell=", 5);
	strcpy(options + 5, super->volume->cell->name);
	if (super->volume->type == AFSVL_RWVOL || rwpath)
		strcat(options, ",rwpath");

	/* try and do the mount */
	_debug("--- attempting mount %s -o %s ---", devname, options);
	mnt = vfs_kern_mount(&afs_fs_type, 0, devname, options);
	_debug("--- mount result %p ---", mnt);

	free_page((unsigned long) devname);
	free_page((unsigned long) options);
	_leave(" = %p", mnt);
	return mnt;

error:
	put_page(page);
error_no_page:
	free_page((unsigned long) options);
error_no_options:
	free_page((unsigned long) devname);
error_no_devname:
	_leave(" = %d", ret);
	return ERR_PTR(ret);
}

/*
 * handle an automount point
 */
struct vfsmount *afs_d_automount(struct path *path)
{
	struct vfsmount *newmnt;

	_enter("{%pd}", path->dentry);

	newmnt = afs_mntpt_do_automount(path->dentry);
	if (IS_ERR(newmnt))
		return newmnt;

	mntget(newmnt); /* prevent immediate expiration */
	mnt_set_expiry(newmnt, &afs_vfsmounts);
	queue_delayed_work(afs_wq, &afs_mntpt_expiry_timer,
			   afs_mntpt_expiry_timeout * HZ);
	_leave(" = %p", newmnt);
	return newmnt;
}

/*
 * handle mountpoint expiry timer going off
 */
static void afs_mntpt_expiry_timed_out(struct work_struct *work)
{
	_enter("");

	if (!list_empty(&afs_vfsmounts)) {
		mark_mounts_for_expiry(&afs_vfsmounts);
		queue_delayed_work(afs_wq, &afs_mntpt_expiry_timer,
				   afs_mntpt_expiry_timeout * HZ);
	}

	_leave("");
}

/*
 * kill the AFS mountpoint timer if it's still running
 */
void afs_mntpt_kill_timer(void)
{
	_enter("");

	ASSERT(list_empty(&afs_vfsmounts));
	cancel_delayed_work_sync(&afs_mntpt_expiry_timer);
}
cpu_pm.c?h=nds-private-remove&amp;id=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd&amp;id2=950eabbd6ddedc1b08350b9169a6a51b130ebaaf'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</div><div class='commit-msg'>Pull networking fixes from David Miller:

 1) GTP fixes from Andreas Schultz (missing genl module alias, clear IP
    DF on transmit).

 2) Netfilter needs to reflect the fwmark when sending resets, from Pau
    Espin Pedrol.

 3) nftable dump OOPS fix from Liping Zhang.

 4) Fix erroneous setting of VIRTIO_NET_HDR_F_DATA_VALID on transmit,
    from Rolf Neugebauer.

 5) Fix build error of ipt_CLUSTERIP when procfs is disabled, from Arnd
    Bergmann.

 6) Fix regression in handling of NETIF_F_SG in harmonize_features(),
    from Eric Dumazet.

 7) Fix RTNL deadlock wrt. lwtunnel module loading, from David Ahern.

 8) tcp_fastopen_create_child() needs to setup tp-&gt;max_window, from
    Alexey Kodanev.

 9) Missing kmemdup() failure check in ipv6 segment routing code, from
    Eric Dumazet.

10) Don't execute unix_bind() under the bindlock, otherwise we deadlock
    with splice. From WANG Cong.

11) ip6_tnl_parse_tlv_enc_lim() potentially reallocates the skb buffer,
    therefore callers must reload cached header pointers into that skb.
    Fix from Eric Dumazet.

12) Fix various bugs in legacy IRQ fallback handling in alx driver, from
    Tobias Regnery.

13) Do not allow lwtunnel drivers to be unloaded while they are
    referenced by active instances, from Robert Shearman.

14) Fix truncated PHY LED trigger names, from Geert Uytterhoeven.

15) Fix a few regressions from virtio_net XDP support, from John
    Fastabend and Jakub Kicinski.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (102 commits)
  ISDN: eicon: silence misleading array-bounds warning
  net: phy: micrel: add support for KSZ8795
  gtp: fix cross netns recv on gtp socket
  gtp: clear DF bit on GTP packet tx
  gtp: add genl family modules alias
  tcp: don't annotate mark on control socket from tcp_v6_send_response()
  ravb: unmap descriptors when freeing rings
  virtio_net: reject XDP programs using header adjustment
  virtio_net: use dev_kfree_skb for small buffer XDP receive
  r8152: check rx after napi is enabled
  r8152: re-schedule napi for tx
  r8152: avoid start_xmit to schedule napi when napi is disabled
  r8152: avoid start_xmit to call napi_schedule during autosuspend
  net: dsa: Bring back device detaching in dsa_slave_suspend()
  net: phy: leds: Fix truncated LED trigger names
  net: phy: leds: Break dependency of phy.h on phy_led_triggers.h
  net: phy: leds: Clear phy_num_led_triggers on failure to avoid crash
  net-next: ethernet: mediatek: change the compatible string
  Documentation: devicetree: change the mediatek ethernet compatible string
  bnxt_en: Fix RTNL lock usage on bnxt_get_port_module_status().
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=1b1bc42c1692e9b62756323c675a44cb1a1f9dbd'>Diffstat</a> (limited to 'kernel/cpu_pm.c')</div><table summary='diffstat' class='diffstat'>