[deliverable/linux.git] / fs / nfsd / nfs4recover.c

/*
*  Copyright (c) 2004 The Regents of the University of Michigan.
*  All rights reserved.
*
*  Andy Adamson <andros@citi.umich.edu>
*
*  Redistribution and use in source and binary forms, with or without
*  modification, are permitted provided that the following conditions
*  are met:
*
*  1. Redistributions of source code must retain the above copyright
*     notice, this list of conditions and the following disclaimer.
*  2. Redistributions in binary form must reproduce the above copyright
*     notice, this list of conditions and the following disclaimer in the
*     documentation and/or other materials provided with the distribution.
*  3. Neither the name of the University nor the names of its
*     contributors may be used to endorse or promote products derived
*     from this software without specific prior written permission.
*
*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

#include <linux/file.h>
#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/crypto.h>
#include <linux/sched.h>

#include "nfsd.h"
#include "state.h"
#include "vfs.h"

#define NFSDDBG_FACILITY                NFSDDBG_PROC

/* Globals */
static struct file *rec_file;
static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";

static int
nfs4_save_creds(const struct cred **original_creds)
{
	struct cred *new;

	new = prepare_creds();
	if (!new)
		return -ENOMEM;

	new->fsuid = 0;
	new->fsgid = 0;
	*original_creds = override_creds(new);
	put_cred(new);
	return 0;
}

static void
nfs4_reset_creds(const struct cred *original)
{
	revert_creds(original);
}

static void
md5_to_hex(char *out, char *md5)
{
	int i;

	for (i=0; i<16; i++) {
		unsigned char c = md5[i];

		*out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
		*out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
	}
	*out = '\0';
}

__be32
nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
{
	struct xdr_netobj cksum;
	struct hash_desc desc;
	struct scatterlist sg;
	__be32 status = nfserr_jukebox;

	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
			clname->len, clname->data);
	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
	if (IS_ERR(desc.tfm))
		goto out_no_tfm;
	cksum.len = crypto_hash_digestsize(desc.tfm);
	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
	if (cksum.data == NULL)
 		goto out;

	sg_init_one(&sg, clname->data, clname->len);

	if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
		goto out;

	md5_to_hex(dname, cksum.data);

	status = nfs_ok;
out:
	kfree(cksum.data);
	crypto_free_hash(desc.tfm);
out_no_tfm:
	return status;
}

void nfsd4_create_clid_dir(struct nfs4_client *clp)
{
	const struct cred *original_cred;
	char *dname = clp->cl_recdir;
	struct dentry *dir, *dentry;
	int status;

	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);

	if (clp->cl_firststate)
		return;
	clp->cl_firststate = 1;
	if (!rec_file)
		return;
	status = nfs4_save_creds(&original_cred);
	if (status < 0)
		return;

	dir = rec_file->f_path.dentry;
	/* lock the parent */
	mutex_lock(&dir->d_inode->i_mutex);

	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
	if (IS_ERR(dentry)) {
		status = PTR_ERR(dentry);
		goto out_unlock;
	}
	if (dentry->d_inode)
		/*
		 * In the 4.1 case, where we're called from
		 * reclaim_complete(), records from the previous reboot
		 * may still be left, so this is OK.
		 *
		 * In the 4.0 case, we should never get here; but we may
		 * as well be forgiving and just succeed silently.
		 */
		goto out_put;
	status = mnt_want_write_file(rec_file);
	if (status)
		goto out_put;
	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
	mnt_drop_write_file(rec_file);
out_put:
	dput(dentry);
out_unlock:
	mutex_unlock(&dir->d_inode->i_mutex);
	if (status == 0)
		vfs_fsync(rec_file, 0);
	else
		printk(KERN_ERR "NFSD: failed to write recovery record"
				" (err %d); please check that %s exists"
				" and is writeable", status,
				user_recovery_dirname);
	nfs4_reset_creds(original_cred);
}

typedef int (recdir_func)(struct dentry *, struct dentry *);

struct name_list {
	char name[HEXDIR_LEN];
	struct list_head list;
};

static int
nfsd4_build_namelist(void *arg, const char *name, int namlen,
		loff_t offset, u64 ino, unsigned int d_type)
{
	struct list_head *names = arg;
	struct name_list *entry;

	if (namlen != HEXDIR_LEN - 1)
		return 0;
	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
	if (entry == NULL)
		return -ENOMEM;
	memcpy(entry->name, name, HEXDIR_LEN - 1);
	entry->name[HEXDIR_LEN - 1] = '\0';
	list_add(&entry->list, names);
	return 0;
}

static int
nfsd4_list_rec_dir(recdir_func *f)
{
	const struct cred *original_cred;
	struct dentry *dir = rec_file->f_path.dentry;
	LIST_HEAD(names);
	int status;

	status = nfs4_save_creds(&original_cred);
	if (status < 0)
		return status;

	status = vfs_llseek(rec_file, 0, SEEK_SET);
	if (status < 0) {
		nfs4_reset_creds(original_cred);
		return status;
	}

	status = vfs_readdir(rec_file, nfsd4_build_namelist, &names);
	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
	while (!list_empty(&names)) {
		struct name_list *entry;
		entry = list_entry(names.next, struct name_list, list);
		if (!status) {
			struct dentry *dentry;
			dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
			if (IS_ERR(dentry)) {
				status = PTR_ERR(dentry);
				break;
			}
			status = f(dir, dentry);
			dput(dentry);
		}
		list_del(&entry->list);
		kfree(entry);
	}
	mutex_unlock(&dir->d_inode->i_mutex);
	nfs4_reset_creds(original_cred);
	return status;
}

static int
nfsd4_unlink_clid_dir(char *name, int namlen)
{
	struct dentry *dir, *dentry;
	int status;

	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);

	dir = rec_file->f_path.dentry;
	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
	dentry = lookup_one_len(name, dir, namlen);
	if (IS_ERR(dentry)) {
		status = PTR_ERR(dentry);
		goto out_unlock;
	}
	status = -ENOENT;
	if (!dentry->d_inode)
		goto out;
	status = vfs_rmdir(dir->d_inode, dentry);
out:
	dput(dentry);
out_unlock:
	mutex_unlock(&dir->d_inode->i_mutex);
	return status;
}

void
nfsd4_remove_clid_dir(struct nfs4_client *clp)
{
	const struct cred *original_cred;
	int status;

	if (!rec_file || !clp->cl_firststate)
		return;

	status = mnt_want_write_file(rec_file);
	if (status)
		goto out;
	clp->cl_firststate = 0;

	status = nfs4_save_creds(&original_cred);
	if (status < 0)
		goto out;

	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
	nfs4_reset_creds(original_cred);
	if (status == 0)
		vfs_fsync(rec_file, 0);
	mnt_drop_write_file(rec_file);
out:
	if (status)
		printk("NFSD: Failed to remove expired client state directory"
				" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	return;
}

static int
purge_old(struct dentry *parent, struct dentry *child)
{
	int status;

	if (nfs4_has_reclaimed_state(child->d_name.name, false))
		return 0;

	status = vfs_rmdir(parent->d_inode, child);
	if (status)
		printk("failed to remove client recovery directory %s\n",
				child->d_name.name);
	/* Keep trying, success or failure: */
	return 0;
}

void
nfsd4_recdir_purge_old(void) {
	int status;

	if (!rec_file)
		return;
	status = mnt_want_write_file(rec_file);
	if (status)
		goto out;
	status = nfsd4_list_rec_dir(purge_old);
	if (status == 0)
		vfs_fsync(rec_file, 0);
	mnt_drop_write_file(rec_file);
out:
	if (status)
		printk("nfsd4: failed to purge old clients from recovery"
			" directory %s\n", rec_file->f_path.dentry->d_name.name);
}

static int
load_recdir(struct dentry *parent, struct dentry *child)
{
	if (child->d_name.len != HEXDIR_LEN - 1) {
		printk("nfsd4: illegal name %s in recovery directory\n",
				child->d_name.name);
		/* Keep trying; maybe the others are OK: */
		return 0;
	}
	nfs4_client_to_reclaim(child->d_name.name);
	return 0;
}

int
nfsd4_recdir_load(void) {
	int status;

	if (!rec_file)
		return 0;

	status = nfsd4_list_rec_dir(load_recdir);
	if (status)
		printk("nfsd4: failed loading clients from recovery"
			" directory %s\n", rec_file->f_path.dentry->d_name.name);
	return status;
}

/*
 * Hold reference to the recovery directory.
 */

void
nfsd4_init_recdir()
{
	const struct cred *original_cred;
	int status;

	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
			user_recovery_dirname);

	BUG_ON(rec_file);

	status = nfs4_save_creds(&original_cred);
	if (status < 0) {
		printk("NFSD: Unable to change credentials to find recovery"
		       " directory: error %d\n",
		       status);
		return;
	}

	rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0);
	if (IS_ERR(rec_file)) {
		printk("NFSD: unable to find recovery directory %s\n",
				user_recovery_dirname);
		rec_file = NULL;
	}

	nfs4_reset_creds(original_cred);
}

void
nfsd4_shutdown_recdir(void)
{
	if (!rec_file)
		return;
	fput(rec_file);
	rec_file = NULL;
}

/*
 * Change the NFSv4 recovery directory to recdir.
 */
int
nfs4_reset_recoverydir(char *recdir)
{
	int status;
	struct path path;

	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
	if (status)
		return status;
	status = -ENOTDIR;
	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
		strcpy(user_recovery_dirname, recdir);
		status = 0;
	}
	path_put(&path);
	return status;
}

char *
nfs4_recoverydir(void)
{
	return user_recovery_dirname;
}
Commit	Line	Data
a55370a3	1	/*
a55370a3 N	2	* Copyright (c) 2004 The Regents of the University of Michigan.
	3	* All rights reserved.
	4	*
	5	* Andy Adamson <andros@citi.umich.edu>
	6	*
	7	* Redistribution and use in source and binary forms, with or without
	8	* modification, are permitted provided that the following conditions
	9	* are met:
	10	*
	11	* 1. Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* 2. Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in the
	15	* documentation and/or other materials provided with the distribution.
	16	* 3. Neither the name of the University nor the names of its
	17	* contributors may be used to endorse or promote products derived
	18	* from this software without specific prior written permission.
	19	*
	20	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	21	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	22	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	23	* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	25	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	26	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	27	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	28	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	29	* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	30	* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	31	*
	32	*/
	33
190e4fbf	34	#include <linux/file.h>
5a0e3ad6	35	#include <linux/slab.h>
190e4fbf	36	#include <linux/namei.h>
a55370a3	37	#include <linux/crypto.h>
e8edc6e0	38	#include <linux/sched.h>
9a74af21 BH	39
	40	#include "nfsd.h"
	41	#include "state.h"
0a3adade	42	#include "vfs.h"
a55370a3 N	43
	44	#define NFSDDBG_FACILITY NFSDDBG_PROC
	45
190e4fbf	46	/* Globals */
e970a573	47	static struct file *rec_file;
48483bf2	48	static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
190e4fbf	49
d84f4f99 DH	50	static int
d84f4f99 DH	51	nfs4_save_creds(const struct cred **original_creds)
190e4fbf	52	{
d84f4f99 DH	53	struct cred *new;
	54
	55	new = prepare_creds();
	56	if (!new)
	57	return -ENOMEM;
	58
	59	new->fsuid = 0;
	60	new->fsgid = 0;
	61	*original_creds = override_creds(new);
	62	put_cred(new);
	63	return 0;
190e4fbf N	64	}
	65
	66	static void
d84f4f99	67	nfs4_reset_creds(const struct cred *original)
190e4fbf	68	{
d84f4f99	69	revert_creds(original);
190e4fbf N	70	}
190e4fbf N	71
a55370a3 N	72	static void
	73	md5_to_hex(char out, char md5)
	74	{
	75	int i;
	76
	77	for (i=0; i<16; i++) {
	78	unsigned char c = md5[i];
	79
	80	out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)('a'-'9'-1);
	81	out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)('a'-'9'-1);
	82	}
	83	*out = '\0';
	84	}
	85
b37ad28b	86	__be32
a55370a3 N	87	nfs4_make_rec_clidname(char dname, struct xdr_netobj clname)
	88	{
	89	struct xdr_netobj cksum;
35058687	90	struct hash_desc desc;
60c74f81	91	struct scatterlist sg;
3e772463	92	__be32 status = nfserr_jukebox;
a55370a3 N	93
	94	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
	95	clname->len, clname->data);
35058687 HX	96	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
	97	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
	98	if (IS_ERR(desc.tfm))
	99	goto out_no_tfm;
	100	cksum.len = crypto_hash_digestsize(desc.tfm);
a55370a3 N	101	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
	102	if (cksum.data == NULL)
	103	goto out;
a55370a3	104
60c74f81	105	sg_init_one(&sg, clname->data, clname->len);
a55370a3	106
60c74f81	107	if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
35058687	108	goto out;
a55370a3 N	109
	110	md5_to_hex(dname, cksum.data);
	111
a55370a3 N	112	status = nfs_ok;
a55370a3 N	113	out:
2bd9e7b6	114	kfree(cksum.data);
35058687 HX	115	crypto_free_hash(desc.tfm);
35058687 HX	116	out_no_tfm:
a55370a3 N	117	return status;
a55370a3 N	118	}
190e4fbf	119
7a6ef8c7	120	void nfsd4_create_clid_dir(struct nfs4_client *clp)
c7b9a459	121	{
d84f4f99	122	const struct cred *original_cred;
c7b9a459	123	char *dname = clp->cl_recdir;
e970a573	124	struct dentry dir, dentry;
c7b9a459 N	125	int status;
	126
	127	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
	128
b8548894	129	if (clp->cl_firststate)
7a6ef8c7	130	return;
6577aac0	131	clp->cl_firststate = 1;
b8548894	132	if (!rec_file)
7a6ef8c7	133	return;
d84f4f99 DH	134	status = nfs4_save_creds(&original_cred);
d84f4f99 DH	135	if (status < 0)
7a6ef8c7	136	return;
c7b9a459	137
e970a573	138	dir = rec_file->f_path.dentry;
c7b9a459	139	/* lock the parent */
e970a573	140	mutex_lock(&dir->d_inode->i_mutex);
c7b9a459	141
e970a573	142	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
c7b9a459 N	143	if (IS_ERR(dentry)) {
	144	status = PTR_ERR(dentry);
	145	goto out_unlock;
	146	}
6577aac0	147	if (dentry->d_inode)
aec39680 BF	148	/*
	149	* In the 4.1 case, where we're called from
	150	* reclaim_complete(), records from the previous reboot
	151	* may still be left, so this is OK.
	152	*
	153	* In the 4.0 case, we should never get here; but we may
	154	* as well be forgiving and just succeed silently.
	155	*/
c7b9a459	156	goto out_put;
a561be71	157	status = mnt_want_write_file(rec_file);
463c3197 DH	158	if (status)
463c3197 DH	159	goto out_put;
e970a573	160	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
2a79f17e	161	mnt_drop_write_file(rec_file);
c7b9a459 N	162	out_put:
	163	dput(dentry);
	164	out_unlock:
e970a573	165	mutex_unlock(&dir->d_inode->i_mutex);
6577aac0	166	if (status == 0)
8018ab05	167	vfs_fsync(rec_file, 0);
6577aac0 BH	168	else
	169	printk(KERN_ERR "NFSD: failed to write recovery record"
	170	" (err %d); please check that %s exists"
	171	" and is writeable", status,
	172	user_recovery_dirname);
d84f4f99	173	nfs4_reset_creds(original_cred);
c7b9a459 N	174	}
c7b9a459 N	175
190e4fbf N	176	typedef int (recdir_func)(struct dentry , struct dentry );
190e4fbf N	177
05f4f678 BF	178	struct name_list {
05f4f678 BF	179	char name[HEXDIR_LEN];
190e4fbf N	180	struct list_head list;
	181	};
	182
190e4fbf	183	static int
05f4f678	184	nfsd4_build_namelist(void arg, const char name, int namlen,
afefdbb2	185	loff_t offset, u64 ino, unsigned int d_type)
190e4fbf	186	{
05f4f678 BF	187	struct list_head *names = arg;
05f4f678 BF	188	struct name_list *entry;
190e4fbf	189
05f4f678	190	if (namlen != HEXDIR_LEN - 1)
b37ad28b	191	return 0;
05f4f678 BF	192	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
05f4f678 BF	193	if (entry == NULL)
190e4fbf	194	return -ENOMEM;
05f4f678 BF	195	memcpy(entry->name, name, HEXDIR_LEN - 1);
	196	entry->name[HEXDIR_LEN - 1] = '\0';
	197	list_add(&entry->list, names);
190e4fbf N	198	return 0;
	199	}
	200
	201	static int
5b4b299c	202	nfsd4_list_rec_dir(recdir_func *f)
190e4fbf	203	{
d84f4f99	204	const struct cred *original_cred;
5b4b299c	205	struct dentry *dir = rec_file->f_path.dentry;
05f4f678	206	LIST_HEAD(names);
190e4fbf N	207	int status;
190e4fbf N	208
d84f4f99 DH	209	status = nfs4_save_creds(&original_cred);
	210	if (status < 0)
	211	return status;
190e4fbf	212
5b4b299c AV	213	status = vfs_llseek(rec_file, 0, SEEK_SET);
	214	if (status < 0) {
	215	nfs4_reset_creds(original_cred);
	216	return status;
	217	}
	218
	219	status = vfs_readdir(rec_file, nfsd4_build_namelist, &names);
8daed1e5	220	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678	221	while (!list_empty(&names)) {
5b4b299c	222	struct name_list *entry;
05f4f678	223	entry = list_entry(names.next, struct name_list, list);
5b4b299c AV	224	if (!status) {
	225	struct dentry *dentry;
	226	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	227	if (IS_ERR(dentry)) {
	228	status = PTR_ERR(dentry);
	229	break;
	230	}
	231	status = f(dir, dentry);
	232	dput(dentry);
05f4f678	233	}
05f4f678 BF	234	list_del(&entry->list);
05f4f678 BF	235	kfree(entry);
190e4fbf	236	}
2f9092e1	237	mutex_unlock(&dir->d_inode->i_mutex);
d84f4f99	238	nfs4_reset_creds(original_cred);
190e4fbf N	239	return status;
	240	}
	241
c7b9a459 N	242	static int
	243	nfsd4_unlink_clid_dir(char *name, int namlen)
	244	{
e970a573	245	struct dentry dir, dentry;
c7b9a459 N	246	int status;
	247
	248	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	249
e970a573 CH	250	dir = rec_file->f_path.dentry;
	251	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
	252	dentry = lookup_one_len(name, dir, namlen);
c7b9a459 N	253	if (IS_ERR(dentry)) {
c7b9a459 N	254	status = PTR_ERR(dentry);
2f9092e1	255	goto out_unlock;
c7b9a459 N	256	}
	257	status = -ENOENT;
	258	if (!dentry->d_inode)
	259	goto out;
e970a573	260	status = vfs_rmdir(dir->d_inode, dentry);
c7b9a459 N	261	out:
c7b9a459 N	262	dput(dentry);
2f9092e1	263	out_unlock:
e970a573	264	mutex_unlock(&dir->d_inode->i_mutex);
c7b9a459 N	265	return status;
	266	}
	267
	268	void
	269	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	270	{
d84f4f99	271	const struct cred *original_cred;
c7b9a459 N	272	int status;
c7b9a459 N	273
e970a573	274	if (!rec_file \|\| !clp->cl_firststate)
c7b9a459 N	275	return;
c7b9a459 N	276
a561be71	277	status = mnt_want_write_file(rec_file);
0622753b DH	278	if (status)
0622753b DH	279	goto out;
67be4313	280	clp->cl_firststate = 0;
d84f4f99 DH	281
	282	status = nfs4_save_creds(&original_cred);
	283	if (status < 0)
	284	goto out;
	285
c7b9a459	286	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	287	nfs4_reset_creds(original_cred);
c7b9a459	288	if (status == 0)
8018ab05	289	vfs_fsync(rec_file, 0);
2a79f17e	290	mnt_drop_write_file(rec_file);
0622753b	291	out:
c7b9a459 N	292	if (status)
	293	printk("NFSD: Failed to remove expired client state directory"
	294	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	295	return;
	296	}
	297
	298	static int
	299	purge_old(struct dentry parent, struct dentry child)
	300	{
	301	int status;
	302
a1bcecd2	303	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	304	return 0;
c7b9a459	305
2f9092e1	306	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	307	if (status)
	308	printk("failed to remove client recovery directory %s\n",
	309	child->d_name.name);
	310	/* Keep trying, success or failure: */
b37ad28b	311	return 0;
c7b9a459 N	312	}
	313
	314	void
	315	nfsd4_recdir_purge_old(void) {
	316	int status;
	317
e970a573	318	if (!rec_file)
c7b9a459	319	return;
a561be71	320	status = mnt_want_write_file(rec_file);
0622753b DH	321	if (status)
0622753b DH	322	goto out;
5b4b299c	323	status = nfsd4_list_rec_dir(purge_old);
c7b9a459	324	if (status == 0)
8018ab05	325	vfs_fsync(rec_file, 0);
2a79f17e	326	mnt_drop_write_file(rec_file);
0622753b	327	out:
c7b9a459 N	328	if (status)
c7b9a459 N	329	printk("nfsd4: failed to purge old clients from recovery"
e970a573	330	" directory %s\n", rec_file->f_path.dentry->d_name.name);
c7b9a459 N	331	}
c7b9a459 N	332
190e4fbf N	333	static int
	334	load_recdir(struct dentry parent, struct dentry child)
	335	{
	336	if (child->d_name.len != HEXDIR_LEN - 1) {
	337	printk("nfsd4: illegal name %s in recovery directory\n",
	338	child->d_name.name);
	339	/* Keep trying; maybe the others are OK: */
b37ad28b	340	return 0;
190e4fbf N	341	}
190e4fbf N	342	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	343	return 0;
190e4fbf N	344	}
	345
	346	int
	347	nfsd4_recdir_load(void) {
	348	int status;
	349
e970a573 CH	350	if (!rec_file)
	351	return 0;
	352
5b4b299c	353	status = nfsd4_list_rec_dir(load_recdir);
190e4fbf N	354	if (status)
190e4fbf N	355	printk("nfsd4: failed loading clients from recovery"
e970a573	356	" directory %s\n", rec_file->f_path.dentry->d_name.name);
190e4fbf N	357	return status;
	358	}
	359
	360	/*
	361	* Hold reference to the recovery directory.
	362	*/
	363
	364	void
48483bf2	365	nfsd4_init_recdir()
190e4fbf	366	{
d84f4f99 DH	367	const struct cred *original_cred;
d84f4f99 DH	368	int status;
190e4fbf N	369
190e4fbf N	370	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
48483bf2	371	user_recovery_dirname);
190e4fbf	372
e970a573	373	BUG_ON(rec_file);
190e4fbf	374
d84f4f99 DH	375	status = nfs4_save_creds(&original_cred);
	376	if (status < 0) {
	377	printk("NFSD: Unable to change credentials to find recovery"
	378	" directory: error %d\n",
	379	status);
	380	return;
	381	}
190e4fbf	382
48483bf2	383	rec_file = filp_open(user_recovery_dirname, O_RDONLY \| O_DIRECTORY, 0);
e970a573	384	if (IS_ERR(rec_file)) {
c2642ab0	385	printk("NFSD: unable to find recovery directory %s\n",
48483bf2	386	user_recovery_dirname);
e970a573 CH	387	rec_file = NULL;
e970a573 CH	388	}
190e4fbf	389
d84f4f99	390	nfs4_reset_creds(original_cred);
190e4fbf N	391	}
	392
	393	void
	394	nfsd4_shutdown_recdir(void)
	395	{
e970a573	396	if (!rec_file)
190e4fbf	397	return;
e970a573 CH	398	fput(rec_file);
e970a573 CH	399	rec_file = NULL;
190e4fbf	400	}
48483bf2 BF	401
	402	/*
	403	* Change the NFSv4 recovery directory to recdir.
	404	*/
	405	int
	406	nfs4_reset_recoverydir(char *recdir)
	407	{
	408	int status;
	409	struct path path;
	410
	411	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
	412	if (status)
	413	return status;
	414	status = -ENOTDIR;
	415	if (S_ISDIR(path.dentry->d_inode->i_mode)) {
	416	strcpy(user_recovery_dirname, recdir);
	417	status = 0;
	418	}
	419	path_put(&path);
	420	return status;
	421	}
	422
	423	char *
	424	nfs4_recoverydir(void)
	425	{
	426	return user_recovery_dirname;
	427	}