[net-next-2.6.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/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 N	34	#include <linux/file.h>
190e4fbf N	35	#include <linux/namei.h>
a55370a3	36	#include <linux/crypto.h>
e8edc6e0	37	#include <linux/sched.h>
9a74af21 BH	38
	39	#include "nfsd.h"
	40	#include "state.h"
0a3adade	41	#include "vfs.h"
a55370a3 N	42
	43	#define NFSDDBG_FACILITY NFSDDBG_PROC
	44
190e4fbf	45	/* Globals */
a63bb996	46	static struct path rec_dir;
190e4fbf N	47	static int rec_dir_init = 0;
190e4fbf N	48
d84f4f99 DH	49	static int
d84f4f99 DH	50	nfs4_save_creds(const struct cred **original_creds)
190e4fbf	51	{
d84f4f99 DH	52	struct cred *new;
	53
	54	new = prepare_creds();
	55	if (!new)
	56	return -ENOMEM;
	57
	58	new->fsuid = 0;
	59	new->fsgid = 0;
	60	*original_creds = override_creds(new);
	61	put_cred(new);
	62	return 0;
190e4fbf N	63	}
	64
	65	static void
d84f4f99	66	nfs4_reset_creds(const struct cred *original)
190e4fbf	67	{
d84f4f99	68	revert_creds(original);
190e4fbf N	69	}
190e4fbf N	70
a55370a3 N	71	static void
	72	md5_to_hex(char out, char md5)
	73	{
	74	int i;
	75
	76	for (i=0; i<16; i++) {
	77	unsigned char c = md5[i];
	78
	79	out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)('a'-'9'-1);
	80	out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)('a'-'9'-1);
	81	}
	82	*out = '\0';
	83	}
	84
b37ad28b	85	__be32
a55370a3 N	86	nfs4_make_rec_clidname(char dname, struct xdr_netobj clname)
	87	{
	88	struct xdr_netobj cksum;
35058687	89	struct hash_desc desc;
60c74f81	90	struct scatterlist sg;
b37ad28b	91	__be32 status = nfserr_resource;
a55370a3 N	92
	93	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
	94	clname->len, clname->data);
35058687 HX	95	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
	96	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
	97	if (IS_ERR(desc.tfm))
	98	goto out_no_tfm;
	99	cksum.len = crypto_hash_digestsize(desc.tfm);
a55370a3 N	100	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
	101	if (cksum.data == NULL)
	102	goto out;
a55370a3	103
60c74f81	104	sg_init_one(&sg, clname->data, clname->len);
a55370a3	105
60c74f81	106	if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
35058687	107	goto out;
a55370a3 N	108
	109	md5_to_hex(dname, cksum.data);
	110
a55370a3 N	111	status = nfs_ok;
a55370a3 N	112	out:
2bd9e7b6	113	kfree(cksum.data);
35058687 HX	114	crypto_free_hash(desc.tfm);
35058687 HX	115	out_no_tfm:
a55370a3 N	116	return status;
a55370a3 N	117	}
190e4fbf	118
a6ccbbb8 N	119	static void
a6ccbbb8 N	120	nfsd4_sync_rec_dir(void)
c7b9a459	121	{
f501912a	122	vfs_fsync(NULL, rec_dir.dentry, 0);
c7b9a459 N	123	}
	124
	125	int
	126	nfsd4_create_clid_dir(struct nfs4_client *clp)
	127	{
d84f4f99	128	const struct cred *original_cred;
c7b9a459 N	129	char *dname = clp->cl_recdir;
c7b9a459 N	130	struct dentry *dentry;
c7b9a459 N	131	int status;
	132
	133	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
	134
	135	if (!rec_dir_init \|\| clp->cl_firststate)
	136	return 0;
	137
d84f4f99 DH	138	status = nfs4_save_creds(&original_cred);
	139	if (status < 0)
	140	return status;
c7b9a459 N	141
c7b9a459 N	142	/* lock the parent */
a63bb996	143	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459	144
a63bb996	145	dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
c7b9a459 N	146	if (IS_ERR(dentry)) {
	147	status = PTR_ERR(dentry);
	148	goto out_unlock;
	149	}
	150	status = -EEXIST;
	151	if (dentry->d_inode) {
	152	dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
	153	goto out_put;
	154	}
a63bb996	155	status = mnt_want_write(rec_dir.mnt);
463c3197 DH	156	if (status)
463c3197 DH	157	goto out_put;
a63bb996 AV	158	status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
a63bb996 AV	159	mnt_drop_write(rec_dir.mnt);
c7b9a459 N	160	out_put:
	161	dput(dentry);
	162	out_unlock:
a63bb996	163	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	164	if (status == 0) {
c7b9a459 N	165	clp->cl_firststate = 1;
a6ccbbb8	166	nfsd4_sync_rec_dir();
c7b9a459	167	}
d84f4f99	168	nfs4_reset_creds(original_cred);
c7b9a459 N	169	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	170	return status;
	171	}
	172
190e4fbf N	173	typedef int (recdir_func)(struct dentry , struct dentry );
190e4fbf N	174
05f4f678 BF	175	struct name_list {
05f4f678 BF	176	char name[HEXDIR_LEN];
190e4fbf N	177	struct list_head list;
	178	};
	179
190e4fbf	180	static int
05f4f678	181	nfsd4_build_namelist(void arg, const char name, int namlen,
afefdbb2	182	loff_t offset, u64 ino, unsigned int d_type)
190e4fbf	183	{
05f4f678 BF	184	struct list_head *names = arg;
05f4f678 BF	185	struct name_list *entry;
190e4fbf	186
05f4f678	187	if (namlen != HEXDIR_LEN - 1)
b37ad28b	188	return 0;
05f4f678 BF	189	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
05f4f678 BF	190	if (entry == NULL)
190e4fbf	191	return -ENOMEM;
05f4f678 BF	192	memcpy(entry->name, name, HEXDIR_LEN - 1);
	193	entry->name[HEXDIR_LEN - 1] = '\0';
	194	list_add(&entry->list, names);
190e4fbf N	195	return 0;
	196	}
	197
	198	static int
	199	nfsd4_list_rec_dir(struct dentry dir, recdir_func f)
	200	{
d84f4f99	201	const struct cred *original_cred;
190e4fbf	202	struct file *filp;
05f4f678 BF	203	LIST_HEAD(names);
	204	struct name_list *entry;
	205	struct dentry *dentry;
190e4fbf N	206	int status;
	207
	208	if (!rec_dir_init)
	209	return 0;
	210
d84f4f99 DH	211	status = nfs4_save_creds(&original_cred);
	212	if (status < 0)
	213	return status;
190e4fbf	214
745ca247 DH	215	filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
745ca247 DH	216	current_cred());
190e4fbf N	217	status = PTR_ERR(filp);
	218	if (IS_ERR(filp))
	219	goto out;
05f4f678	220	status = vfs_readdir(filp, nfsd4_build_namelist, &names);
190e4fbf	221	fput(filp);
8daed1e5	222	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678 BF	223	while (!list_empty(&names)) {
	224	entry = list_entry(names.next, struct name_list, list);
	225
	226	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	227	if (IS_ERR(dentry)) {
	228	status = PTR_ERR(dentry);
2f9092e1	229	break;
05f4f678 BF	230	}
	231	status = f(dir, dentry);
	232	dput(dentry);
190e4fbf	233	if (status)
2f9092e1	234	break;
05f4f678 BF	235	list_del(&entry->list);
05f4f678 BF	236	kfree(entry);
190e4fbf	237	}
2f9092e1	238	mutex_unlock(&dir->d_inode->i_mutex);
190e4fbf	239	out:
05f4f678 BF	240	while (!list_empty(&names)) {
	241	entry = list_entry(names.next, struct name_list, list);
	242	list_del(&entry->list);
	243	kfree(entry);
190e4fbf	244	}
d84f4f99	245	nfs4_reset_creds(original_cred);
190e4fbf N	246	return status;
	247	}
	248
c7b9a459 N	249	static int
	250	nfsd4_unlink_clid_dir(char *name, int namlen)
	251	{
	252	struct dentry *dentry;
	253	int status;
	254
	255	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	256
8daed1e5	257	mutex_lock_nested(&rec_dir.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
a63bb996	258	dentry = lookup_one_len(name, rec_dir.dentry, namlen);
c7b9a459 N	259	if (IS_ERR(dentry)) {
c7b9a459 N	260	status = PTR_ERR(dentry);
2f9092e1	261	goto out_unlock;
c7b9a459 N	262	}
	263	status = -ENOENT;
	264	if (!dentry->d_inode)
	265	goto out;
2f9092e1	266	status = vfs_rmdir(rec_dir.dentry->d_inode, dentry);
c7b9a459 N	267	out:
c7b9a459 N	268	dput(dentry);
2f9092e1 DW	269	out_unlock:
2f9092e1 DW	270	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	271	return status;
	272	}
	273
	274	void
	275	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	276	{
d84f4f99	277	const struct cred *original_cred;
c7b9a459 N	278	int status;
	279
	280	if (!rec_dir_init \|\| !clp->cl_firststate)
	281	return;
	282
a63bb996	283	status = mnt_want_write(rec_dir.mnt);
0622753b DH	284	if (status)
0622753b DH	285	goto out;
67be4313	286	clp->cl_firststate = 0;
d84f4f99 DH	287
	288	status = nfs4_save_creds(&original_cred);
	289	if (status < 0)
	290	goto out;
	291
c7b9a459	292	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	293	nfs4_reset_creds(original_cred);
c7b9a459	294	if (status == 0)
a6ccbbb8	295	nfsd4_sync_rec_dir();
a63bb996	296	mnt_drop_write(rec_dir.mnt);
0622753b	297	out:
c7b9a459 N	298	if (status)
	299	printk("NFSD: Failed to remove expired client state directory"
	300	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	301	return;
	302	}
	303
	304	static int
	305	purge_old(struct dentry parent, struct dentry child)
	306	{
	307	int status;
	308
a1bcecd2 AA	309	/* note: we currently use this path only for minorversion 0 */
a1bcecd2 AA	310	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	311	return 0;
c7b9a459	312
2f9092e1	313	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	314	if (status)
	315	printk("failed to remove client recovery directory %s\n",
	316	child->d_name.name);
	317	/* Keep trying, success or failure: */
b37ad28b	318	return 0;
c7b9a459 N	319	}
	320
	321	void
	322	nfsd4_recdir_purge_old(void) {
	323	int status;
	324
	325	if (!rec_dir_init)
	326	return;
a63bb996	327	status = mnt_want_write(rec_dir.mnt);
0622753b DH	328	if (status)
0622753b DH	329	goto out;
a63bb996	330	status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
c7b9a459	331	if (status == 0)
a6ccbbb8	332	nfsd4_sync_rec_dir();
a63bb996	333	mnt_drop_write(rec_dir.mnt);
0622753b	334	out:
c7b9a459 N	335	if (status)
c7b9a459 N	336	printk("nfsd4: failed to purge old clients from recovery"
a63bb996	337	" directory %s\n", rec_dir.dentry->d_name.name);
c7b9a459 N	338	}
c7b9a459 N	339
190e4fbf N	340	static int
	341	load_recdir(struct dentry parent, struct dentry child)
	342	{
	343	if (child->d_name.len != HEXDIR_LEN - 1) {
	344	printk("nfsd4: illegal name %s in recovery directory\n",
	345	child->d_name.name);
	346	/* Keep trying; maybe the others are OK: */
b37ad28b	347	return 0;
190e4fbf N	348	}
190e4fbf N	349	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	350	return 0;
190e4fbf N	351	}
	352
	353	int
	354	nfsd4_recdir_load(void) {
	355	int status;
	356
a63bb996	357	status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
190e4fbf N	358	if (status)
190e4fbf N	359	printk("nfsd4: failed loading clients from recovery"
a63bb996	360	" directory %s\n", rec_dir.dentry->d_name.name);
190e4fbf N	361	return status;
	362	}
	363
	364	/*
	365	* Hold reference to the recovery directory.
	366	*/
	367
	368	void
	369	nfsd4_init_recdir(char *rec_dirname)
	370	{
d84f4f99 DH	371	const struct cred *original_cred;
d84f4f99 DH	372	int status;
190e4fbf N	373
	374	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
	375	rec_dirname);
	376
	377	BUG_ON(rec_dir_init);
	378
d84f4f99 DH	379	status = nfs4_save_creds(&original_cred);
	380	if (status < 0) {
	381	printk("NFSD: Unable to change credentials to find recovery"
	382	" directory: error %d\n",
	383	status);
	384	return;
	385	}
190e4fbf	386
a63bb996	387	status = kern_path(rec_dirname, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY,
c2642ab0 BF	388	&rec_dir);
	389	if (status)
	390	printk("NFSD: unable to find recovery directory %s\n",
190e4fbf N	391	rec_dirname);
	392
	393	if (!status)
	394	rec_dir_init = 1;
d84f4f99	395	nfs4_reset_creds(original_cred);
190e4fbf N	396	}
	397
	398	void
	399	nfsd4_shutdown_recdir(void)
	400	{
	401	if (!rec_dir_init)
	402	return;
	403	rec_dir_init = 0;
a63bb996	404	path_put(&rec_dir);
190e4fbf	405	}