[mirror_ubuntu-eoan-kernel.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 path rec_dir;
static int rec_dir_init = 0;

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_resource;

	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;
}

static void
nfsd4_sync_rec_dir(void)
{
	vfs_fsync(NULL, rec_dir.dentry, 0);
}

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

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

	if (!rec_dir_init || clp->cl_firststate)
		return 0;

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

	/* lock the parent */
	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);

	dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
	if (IS_ERR(dentry)) {
		status = PTR_ERR(dentry);
		goto out_unlock;
	}
	status = -EEXIST;
	if (dentry->d_inode) {
		dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
		goto out_put;
	}
	status = mnt_want_write(rec_dir.mnt);
	if (status)
		goto out_put;
	status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
	mnt_drop_write(rec_dir.mnt);
out_put:
	dput(dentry);
out_unlock:
	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
	if (status == 0) {
		clp->cl_firststate = 1;
		nfsd4_sync_rec_dir();
	}
	nfs4_reset_creds(original_cred);
	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	return status;
}

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(struct dentry *dir, recdir_func *f)
{
	const struct cred *original_cred;
	struct file *filp;
	LIST_HEAD(names);
	struct name_list *entry;
	struct dentry *dentry;
	int status;

	if (!rec_dir_init)
		return 0;

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

	filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
			   current_cred());
	status = PTR_ERR(filp);
	if (IS_ERR(filp))
		goto out;
	status = vfs_readdir(filp, nfsd4_build_namelist, &names);
	fput(filp);
	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
	while (!list_empty(&names)) {
		entry = list_entry(names.next, struct name_list, list);

		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);
		if (status)
			break;
		list_del(&entry->list);
		kfree(entry);
	}
	mutex_unlock(&dir->d_inode->i_mutex);
out:
	while (!list_empty(&names)) {
		entry = list_entry(names.next, struct name_list, list);
		list_del(&entry->list);
		kfree(entry);
	}
	nfs4_reset_creds(original_cred);
	return status;
}

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

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

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

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

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

	status = mnt_want_write(rec_dir.mnt);
	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)
		nfsd4_sync_rec_dir();
	mnt_drop_write(rec_dir.mnt);
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;

	/* note: we currently use this path only for minorversion 0 */
	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_dir_init)
		return;
	status = mnt_want_write(rec_dir.mnt);
	if (status)
		goto out;
	status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
	if (status == 0)
		nfsd4_sync_rec_dir();
	mnt_drop_write(rec_dir.mnt);
out:
	if (status)
		printk("nfsd4: failed to purge old clients from recovery"
			" directory %s\n", rec_dir.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;

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

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

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

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

	BUG_ON(rec_dir_init);

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

	status = kern_path(rec_dirname, LOOKUP_FOLLOW | LOOKUP_DIRECTORY,
			&rec_dir);
	if (status)
		printk("NFSD: unable to find recovery directory %s\n",
				rec_dirname);

	if (!status)
		rec_dir_init = 1;
	nfs4_reset_creds(original_cred);
}

void
nfsd4_shutdown_recdir(void)
{
	if (!rec_dir_init)
		return;
	rec_dir_init = 0;
	path_put(&rec_dir);
}
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 */
a63bb996	47	static struct path rec_dir;
190e4fbf N	48	static int rec_dir_init = 0;
190e4fbf N	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;
b37ad28b	92	__be32 status = nfserr_resource;
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
a6ccbbb8 N	120	static void
a6ccbbb8 N	121	nfsd4_sync_rec_dir(void)
c7b9a459	122	{
f501912a	123	vfs_fsync(NULL, rec_dir.dentry, 0);
c7b9a459 N	124	}
	125
	126	int
	127	nfsd4_create_clid_dir(struct nfs4_client *clp)
	128	{
d84f4f99	129	const struct cred *original_cred;
c7b9a459 N	130	char *dname = clp->cl_recdir;
c7b9a459 N	131	struct dentry *dentry;
c7b9a459 N	132	int status;
	133
	134	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
	135
	136	if (!rec_dir_init \|\| clp->cl_firststate)
	137	return 0;
	138
d84f4f99 DH	139	status = nfs4_save_creds(&original_cred);
	140	if (status < 0)
	141	return status;
c7b9a459 N	142
c7b9a459 N	143	/* lock the parent */
a63bb996	144	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459	145
a63bb996	146	dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
c7b9a459 N	147	if (IS_ERR(dentry)) {
	148	status = PTR_ERR(dentry);
	149	goto out_unlock;
	150	}
	151	status = -EEXIST;
	152	if (dentry->d_inode) {
	153	dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
	154	goto out_put;
	155	}
a63bb996	156	status = mnt_want_write(rec_dir.mnt);
463c3197 DH	157	if (status)
463c3197 DH	158	goto out_put;
a63bb996 AV	159	status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
a63bb996 AV	160	mnt_drop_write(rec_dir.mnt);
c7b9a459 N	161	out_put:
	162	dput(dentry);
	163	out_unlock:
a63bb996	164	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	165	if (status == 0) {
c7b9a459 N	166	clp->cl_firststate = 1;
a6ccbbb8	167	nfsd4_sync_rec_dir();
c7b9a459	168	}
d84f4f99	169	nfs4_reset_creds(original_cred);
c7b9a459 N	170	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	171	return status;
	172	}
	173
190e4fbf N	174	typedef int (recdir_func)(struct dentry , struct dentry );
190e4fbf N	175
05f4f678 BF	176	struct name_list {
05f4f678 BF	177	char name[HEXDIR_LEN];
190e4fbf N	178	struct list_head list;
	179	};
	180
190e4fbf	181	static int
05f4f678	182	nfsd4_build_namelist(void arg, const char name, int namlen,
afefdbb2	183	loff_t offset, u64 ino, unsigned int d_type)
190e4fbf	184	{
05f4f678 BF	185	struct list_head *names = arg;
05f4f678 BF	186	struct name_list *entry;
190e4fbf	187
05f4f678	188	if (namlen != HEXDIR_LEN - 1)
b37ad28b	189	return 0;
05f4f678 BF	190	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
05f4f678 BF	191	if (entry == NULL)
190e4fbf	192	return -ENOMEM;
05f4f678 BF	193	memcpy(entry->name, name, HEXDIR_LEN - 1);
	194	entry->name[HEXDIR_LEN - 1] = '\0';
	195	list_add(&entry->list, names);
190e4fbf N	196	return 0;
	197	}
	198
	199	static int
	200	nfsd4_list_rec_dir(struct dentry dir, recdir_func f)
	201	{
d84f4f99	202	const struct cred *original_cred;
190e4fbf	203	struct file *filp;
05f4f678 BF	204	LIST_HEAD(names);
	205	struct name_list *entry;
	206	struct dentry *dentry;
190e4fbf N	207	int status;
	208
	209	if (!rec_dir_init)
	210	return 0;
	211
d84f4f99 DH	212	status = nfs4_save_creds(&original_cred);
	213	if (status < 0)
	214	return status;
190e4fbf	215
745ca247 DH	216	filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
745ca247 DH	217	current_cred());
190e4fbf N	218	status = PTR_ERR(filp);
	219	if (IS_ERR(filp))
	220	goto out;
05f4f678	221	status = vfs_readdir(filp, nfsd4_build_namelist, &names);
190e4fbf	222	fput(filp);
8daed1e5	223	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678 BF	224	while (!list_empty(&names)) {
	225	entry = list_entry(names.next, struct name_list, list);
	226
	227	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	228	if (IS_ERR(dentry)) {
	229	status = PTR_ERR(dentry);
2f9092e1	230	break;
05f4f678 BF	231	}
	232	status = f(dir, dentry);
	233	dput(dentry);
190e4fbf	234	if (status)
2f9092e1	235	break;
05f4f678 BF	236	list_del(&entry->list);
05f4f678 BF	237	kfree(entry);
190e4fbf	238	}
2f9092e1	239	mutex_unlock(&dir->d_inode->i_mutex);
190e4fbf	240	out:
05f4f678 BF	241	while (!list_empty(&names)) {
	242	entry = list_entry(names.next, struct name_list, list);
	243	list_del(&entry->list);
	244	kfree(entry);
190e4fbf	245	}
d84f4f99	246	nfs4_reset_creds(original_cred);
190e4fbf N	247	return status;
	248	}
	249
c7b9a459 N	250	static int
	251	nfsd4_unlink_clid_dir(char *name, int namlen)
	252	{
	253	struct dentry *dentry;
	254	int status;
	255
	256	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	257
8daed1e5	258	mutex_lock_nested(&rec_dir.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
a63bb996	259	dentry = lookup_one_len(name, rec_dir.dentry, namlen);
c7b9a459 N	260	if (IS_ERR(dentry)) {
c7b9a459 N	261	status = PTR_ERR(dentry);
2f9092e1	262	goto out_unlock;
c7b9a459 N	263	}
	264	status = -ENOENT;
	265	if (!dentry->d_inode)
	266	goto out;
2f9092e1	267	status = vfs_rmdir(rec_dir.dentry->d_inode, dentry);
c7b9a459 N	268	out:
c7b9a459 N	269	dput(dentry);
2f9092e1 DW	270	out_unlock:
2f9092e1 DW	271	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	272	return status;
	273	}
	274
	275	void
	276	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	277	{
d84f4f99	278	const struct cred *original_cred;
c7b9a459 N	279	int status;
	280
	281	if (!rec_dir_init \|\| !clp->cl_firststate)
	282	return;
	283
a63bb996	284	status = mnt_want_write(rec_dir.mnt);
0622753b DH	285	if (status)
0622753b DH	286	goto out;
67be4313	287	clp->cl_firststate = 0;
d84f4f99 DH	288
	289	status = nfs4_save_creds(&original_cred);
	290	if (status < 0)
	291	goto out;
	292
c7b9a459	293	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	294	nfs4_reset_creds(original_cred);
c7b9a459	295	if (status == 0)
a6ccbbb8	296	nfsd4_sync_rec_dir();
a63bb996	297	mnt_drop_write(rec_dir.mnt);
0622753b	298	out:
c7b9a459 N	299	if (status)
	300	printk("NFSD: Failed to remove expired client state directory"
	301	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	302	return;
	303	}
	304
	305	static int
	306	purge_old(struct dentry parent, struct dentry child)
	307	{
	308	int status;
	309
a1bcecd2 AA	310	/* note: we currently use this path only for minorversion 0 */
a1bcecd2 AA	311	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	312	return 0;
c7b9a459	313
2f9092e1	314	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	315	if (status)
	316	printk("failed to remove client recovery directory %s\n",
	317	child->d_name.name);
	318	/* Keep trying, success or failure: */
b37ad28b	319	return 0;
c7b9a459 N	320	}
	321
	322	void
	323	nfsd4_recdir_purge_old(void) {
	324	int status;
	325
	326	if (!rec_dir_init)
	327	return;
a63bb996	328	status = mnt_want_write(rec_dir.mnt);
0622753b DH	329	if (status)
0622753b DH	330	goto out;
a63bb996	331	status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
c7b9a459	332	if (status == 0)
a6ccbbb8	333	nfsd4_sync_rec_dir();
a63bb996	334	mnt_drop_write(rec_dir.mnt);
0622753b	335	out:
c7b9a459 N	336	if (status)
c7b9a459 N	337	printk("nfsd4: failed to purge old clients from recovery"
a63bb996	338	" directory %s\n", rec_dir.dentry->d_name.name);
c7b9a459 N	339	}
c7b9a459 N	340
190e4fbf N	341	static int
	342	load_recdir(struct dentry parent, struct dentry child)
	343	{
	344	if (child->d_name.len != HEXDIR_LEN - 1) {
	345	printk("nfsd4: illegal name %s in recovery directory\n",
	346	child->d_name.name);
	347	/* Keep trying; maybe the others are OK: */
b37ad28b	348	return 0;
190e4fbf N	349	}
190e4fbf N	350	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	351	return 0;
190e4fbf N	352	}
	353
	354	int
	355	nfsd4_recdir_load(void) {
	356	int status;
	357
a63bb996	358	status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
190e4fbf N	359	if (status)
190e4fbf N	360	printk("nfsd4: failed loading clients from recovery"
a63bb996	361	" directory %s\n", rec_dir.dentry->d_name.name);
190e4fbf N	362	return status;
	363	}
	364
	365	/*
	366	* Hold reference to the recovery directory.
	367	*/
	368
	369	void
	370	nfsd4_init_recdir(char *rec_dirname)
	371	{
d84f4f99 DH	372	const struct cred *original_cred;
d84f4f99 DH	373	int status;
190e4fbf N	374
	375	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
	376	rec_dirname);
	377
	378	BUG_ON(rec_dir_init);
	379
d84f4f99 DH	380	status = nfs4_save_creds(&original_cred);
	381	if (status < 0) {
	382	printk("NFSD: Unable to change credentials to find recovery"
	383	" directory: error %d\n",
	384	status);
	385	return;
	386	}
190e4fbf	387
a63bb996	388	status = kern_path(rec_dirname, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY,
c2642ab0 BF	389	&rec_dir);
	390	if (status)
	391	printk("NFSD: unable to find recovery directory %s\n",
190e4fbf N	392	rec_dirname);
	393
	394	if (!status)
	395	rec_dir_init = 1;
d84f4f99	396	nfs4_reset_creds(original_cred);
190e4fbf N	397	}
	398
	399	void
	400	nfsd4_shutdown_recdir(void)
	401	{
	402	if (!rec_dir_init)
	403	return;
	404	rec_dir_init = 0;
a63bb996	405	path_put(&rec_dir);
190e4fbf	406	}