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

/*
*  linux/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/nfsd/nfsd.h>
#include <linux/nfsd/state.h>
#include <linux/file.h>
#include <linux/namei.h>
#include <linux/crypto.h>
#include <linux/sched.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)
{
	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
	nfsd_sync_dir(rec_dir.dentry);
	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
}

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 N	1	/*
	2	* linux/fs/nfsd/nfs4recover.c
	3	*
	4	* Copyright (c) 2004 The Regents of the University of Michigan.
	5	* All rights reserved.
	6	*
	7	* Andy Adamson <andros@citi.umich.edu>
	8	*
	9	* Redistribution and use in source and binary forms, with or without
	10	* modification, are permitted provided that the following conditions
	11	* are met:
	12	*
	13	* 1. Redistributions of source code must retain the above copyright
	14	* notice, this list of conditions and the following disclaimer.
	15	* 2. Redistributions in binary form must reproduce the above copyright
	16	* notice, this list of conditions and the following disclaimer in the
	17	* documentation and/or other materials provided with the distribution.
	18	* 3. Neither the name of the University nor the names of its
	19	* contributors may be used to endorse or promote products derived
	20	* from this software without specific prior written permission.
	21	*
	22	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
	23	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
	24	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	25	* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	26	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	27	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	28	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	29	* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	30	* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	31	* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	32	* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	33	*
	34	*/
	35
a55370a3	36	#include <linux/nfsd/nfsd.h>
a55370a3	37	#include <linux/nfsd/state.h>
190e4fbf N	38	#include <linux/file.h>
190e4fbf N	39	#include <linux/namei.h>
a55370a3	40	#include <linux/crypto.h>
e8edc6e0	41	#include <linux/sched.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	{
a63bb996 AV	123	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
	124	nfsd_sync_dir(rec_dir.dentry);
	125	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	126	}
	127
	128	int
	129	nfsd4_create_clid_dir(struct nfs4_client *clp)
	130	{
d84f4f99	131	const struct cred *original_cred;
c7b9a459 N	132	char *dname = clp->cl_recdir;
c7b9a459 N	133	struct dentry *dentry;
c7b9a459 N	134	int status;
	135
	136	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
	137
	138	if (!rec_dir_init \|\| clp->cl_firststate)
	139	return 0;
	140
d84f4f99 DH	141	status = nfs4_save_creds(&original_cred);
	142	if (status < 0)
	143	return status;
c7b9a459 N	144
c7b9a459 N	145	/* lock the parent */
a63bb996	146	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459	147
a63bb996	148	dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
c7b9a459 N	149	if (IS_ERR(dentry)) {
	150	status = PTR_ERR(dentry);
	151	goto out_unlock;
	152	}
	153	status = -EEXIST;
	154	if (dentry->d_inode) {
	155	dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
	156	goto out_put;
	157	}
a63bb996	158	status = mnt_want_write(rec_dir.mnt);
463c3197 DH	159	if (status)
463c3197 DH	160	goto out_put;
a63bb996 AV	161	status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
a63bb996 AV	162	mnt_drop_write(rec_dir.mnt);
c7b9a459 N	163	out_put:
	164	dput(dentry);
	165	out_unlock:
a63bb996	166	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	167	if (status == 0) {
c7b9a459 N	168	clp->cl_firststate = 1;
a6ccbbb8	169	nfsd4_sync_rec_dir();
c7b9a459	170	}
d84f4f99	171	nfs4_reset_creds(original_cred);
c7b9a459 N	172	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	173	return status;
	174	}
	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
	202	nfsd4_list_rec_dir(struct dentry dir, recdir_func f)
	203	{
d84f4f99	204	const struct cred *original_cred;
190e4fbf	205	struct file *filp;
05f4f678 BF	206	LIST_HEAD(names);
	207	struct name_list *entry;
	208	struct dentry *dentry;
190e4fbf N	209	int status;
	210
	211	if (!rec_dir_init)
	212	return 0;
	213
d84f4f99 DH	214	status = nfs4_save_creds(&original_cred);
	215	if (status < 0)
	216	return status;
190e4fbf	217
745ca247 DH	218	filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
745ca247 DH	219	current_cred());
190e4fbf N	220	status = PTR_ERR(filp);
	221	if (IS_ERR(filp))
	222	goto out;
05f4f678	223	status = vfs_readdir(filp, nfsd4_build_namelist, &names);
190e4fbf	224	fput(filp);
8daed1e5	225	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678 BF	226	while (!list_empty(&names)) {
	227	entry = list_entry(names.next, struct name_list, list);
	228
	229	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	230	if (IS_ERR(dentry)) {
	231	status = PTR_ERR(dentry);
2f9092e1	232	break;
05f4f678 BF	233	}
	234	status = f(dir, dentry);
	235	dput(dentry);
190e4fbf	236	if (status)
2f9092e1	237	break;
05f4f678 BF	238	list_del(&entry->list);
05f4f678 BF	239	kfree(entry);
190e4fbf	240	}
2f9092e1	241	mutex_unlock(&dir->d_inode->i_mutex);
190e4fbf	242	out:
05f4f678 BF	243	while (!list_empty(&names)) {
	244	entry = list_entry(names.next, struct name_list, list);
	245	list_del(&entry->list);
	246	kfree(entry);
190e4fbf	247	}
d84f4f99	248	nfs4_reset_creds(original_cred);
190e4fbf N	249	return status;
	250	}
	251
c7b9a459 N	252	static int
	253	nfsd4_unlink_clid_dir(char *name, int namlen)
	254	{
	255	struct dentry *dentry;
	256	int status;
	257
	258	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	259
8daed1e5	260	mutex_lock_nested(&rec_dir.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
a63bb996	261	dentry = lookup_one_len(name, rec_dir.dentry, namlen);
c7b9a459 N	262	if (IS_ERR(dentry)) {
c7b9a459 N	263	status = PTR_ERR(dentry);
2f9092e1	264	goto out_unlock;
c7b9a459 N	265	}
	266	status = -ENOENT;
	267	if (!dentry->d_inode)
	268	goto out;
2f9092e1	269	status = vfs_rmdir(rec_dir.dentry->d_inode, dentry);
c7b9a459 N	270	out:
c7b9a459 N	271	dput(dentry);
2f9092e1 DW	272	out_unlock:
2f9092e1 DW	273	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	274	return status;
	275	}
	276
	277	void
	278	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	279	{
d84f4f99	280	const struct cred *original_cred;
c7b9a459 N	281	int status;
	282
	283	if (!rec_dir_init \|\| !clp->cl_firststate)
	284	return;
	285
a63bb996	286	status = mnt_want_write(rec_dir.mnt);
0622753b DH	287	if (status)
0622753b DH	288	goto out;
67be4313	289	clp->cl_firststate = 0;
d84f4f99 DH	290
	291	status = nfs4_save_creds(&original_cred);
	292	if (status < 0)
	293	goto out;
	294
c7b9a459	295	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	296	nfs4_reset_creds(original_cred);
c7b9a459	297	if (status == 0)
a6ccbbb8	298	nfsd4_sync_rec_dir();
a63bb996	299	mnt_drop_write(rec_dir.mnt);
0622753b	300	out:
c7b9a459 N	301	if (status)
	302	printk("NFSD: Failed to remove expired client state directory"
	303	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	304	return;
	305	}
	306
	307	static int
	308	purge_old(struct dentry parent, struct dentry child)
	309	{
	310	int status;
	311
a1bcecd2 AA	312	/* note: we currently use this path only for minorversion 0 */
a1bcecd2 AA	313	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	314	return 0;
c7b9a459	315
2f9092e1	316	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	317	if (status)
	318	printk("failed to remove client recovery directory %s\n",
	319	child->d_name.name);
	320	/* Keep trying, success or failure: */
b37ad28b	321	return 0;
c7b9a459 N	322	}
	323
	324	void
	325	nfsd4_recdir_purge_old(void) {
	326	int status;
	327
	328	if (!rec_dir_init)
	329	return;
a63bb996	330	status = mnt_want_write(rec_dir.mnt);
0622753b DH	331	if (status)
0622753b DH	332	goto out;
a63bb996	333	status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
c7b9a459	334	if (status == 0)
a6ccbbb8	335	nfsd4_sync_rec_dir();
a63bb996	336	mnt_drop_write(rec_dir.mnt);
0622753b	337	out:
c7b9a459 N	338	if (status)
c7b9a459 N	339	printk("nfsd4: failed to purge old clients from recovery"
a63bb996	340	" directory %s\n", rec_dir.dentry->d_name.name);
c7b9a459 N	341	}
c7b9a459 N	342
190e4fbf N	343	static int
	344	load_recdir(struct dentry parent, struct dentry child)
	345	{
	346	if (child->d_name.len != HEXDIR_LEN - 1) {
	347	printk("nfsd4: illegal name %s in recovery directory\n",
	348	child->d_name.name);
	349	/* Keep trying; maybe the others are OK: */
b37ad28b	350	return 0;
190e4fbf N	351	}
190e4fbf N	352	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	353	return 0;
190e4fbf N	354	}
	355
	356	int
	357	nfsd4_recdir_load(void) {
	358	int status;
	359
a63bb996	360	status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
190e4fbf N	361	if (status)
190e4fbf N	362	printk("nfsd4: failed loading clients from recovery"
a63bb996	363	" directory %s\n", rec_dir.dentry->d_name.name);
190e4fbf N	364	return status;
	365	}
	366
	367	/*
	368	* Hold reference to the recovery directory.
	369	*/
	370
	371	void
	372	nfsd4_init_recdir(char *rec_dirname)
	373	{
d84f4f99 DH	374	const struct cred *original_cred;
d84f4f99 DH	375	int status;
190e4fbf N	376
	377	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
	378	rec_dirname);
	379
	380	BUG_ON(rec_dir_init);
	381
d84f4f99 DH	382	status = nfs4_save_creds(&original_cred);
	383	if (status < 0) {
	384	printk("NFSD: Unable to change credentials to find recovery"
	385	" directory: error %d\n",
	386	status);
	387	return;
	388	}
190e4fbf	389
a63bb996	390	status = kern_path(rec_dirname, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY,
c2642ab0 BF	391	&rec_dir);
	392	if (status)
	393	printk("NFSD: unable to find recovery directory %s\n",
190e4fbf N	394	rec_dirname);
	395
	396	if (!status)
	397	rec_dir_init = 1;
d84f4f99	398	nfs4_reset_creds(original_cred);
190e4fbf N	399	}
	400
	401	void
	402	nfsd4_shutdown_recdir(void)
	403	{
	404	if (!rec_dir_init)
	405	return;
	406	rec_dir_init = 0;
a63bb996	407	path_put(&rec_dir);
190e4fbf	408	}