[linux-2.6-block.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/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)
{
	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
190e4fbf N	36	#include <linux/file.h>
190e4fbf N	37	#include <linux/namei.h>
a55370a3	38	#include <linux/crypto.h>
e8edc6e0	39	#include <linux/sched.h>
9a74af21 BH	40
	41	#include "nfsd.h"
	42	#include "state.h"
0a3adade	43	#include "vfs.h"
a55370a3 N	44
	45	#define NFSDDBG_FACILITY NFSDDBG_PROC
	46
190e4fbf	47	/* Globals */
a63bb996	48	static struct path rec_dir;
190e4fbf N	49	static int rec_dir_init = 0;
190e4fbf N	50
d84f4f99 DH	51	static int
d84f4f99 DH	52	nfs4_save_creds(const struct cred **original_creds)
190e4fbf	53	{
d84f4f99 DH	54	struct cred *new;
	55
	56	new = prepare_creds();
	57	if (!new)
	58	return -ENOMEM;
	59
	60	new->fsuid = 0;
	61	new->fsgid = 0;
	62	*original_creds = override_creds(new);
	63	put_cred(new);
	64	return 0;
190e4fbf N	65	}
	66
	67	static void
d84f4f99	68	nfs4_reset_creds(const struct cred *original)
190e4fbf	69	{
d84f4f99	70	revert_creds(original);
190e4fbf N	71	}
190e4fbf N	72
a55370a3 N	73	static void
	74	md5_to_hex(char out, char md5)
	75	{
	76	int i;
	77
	78	for (i=0; i<16; i++) {
	79	unsigned char c = md5[i];
	80
	81	out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)('a'-'9'-1);
	82	out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)('a'-'9'-1);
	83	}
	84	*out = '\0';
	85	}
	86
b37ad28b	87	__be32
a55370a3 N	88	nfs4_make_rec_clidname(char dname, struct xdr_netobj clname)
	89	{
	90	struct xdr_netobj cksum;
35058687	91	struct hash_desc desc;
60c74f81	92	struct scatterlist sg;
b37ad28b	93	__be32 status = nfserr_resource;
a55370a3 N	94
	95	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
	96	clname->len, clname->data);
35058687 HX	97	desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
	98	desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
	99	if (IS_ERR(desc.tfm))
	100	goto out_no_tfm;
	101	cksum.len = crypto_hash_digestsize(desc.tfm);
a55370a3 N	102	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
	103	if (cksum.data == NULL)
	104	goto out;
a55370a3	105
60c74f81	106	sg_init_one(&sg, clname->data, clname->len);
a55370a3	107
60c74f81	108	if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
35058687	109	goto out;
a55370a3 N	110
	111	md5_to_hex(dname, cksum.data);
	112
a55370a3 N	113	status = nfs_ok;
a55370a3 N	114	out:
2bd9e7b6	115	kfree(cksum.data);
35058687 HX	116	crypto_free_hash(desc.tfm);
35058687 HX	117	out_no_tfm:
a55370a3 N	118	return status;
a55370a3 N	119	}
190e4fbf	120
a6ccbbb8 N	121	static void
a6ccbbb8 N	122	nfsd4_sync_rec_dir(void)
c7b9a459	123	{
a63bb996 AV	124	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
	125	nfsd_sync_dir(rec_dir.dentry);
	126	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	127	}
	128
	129	int
	130	nfsd4_create_clid_dir(struct nfs4_client *clp)
	131	{
d84f4f99	132	const struct cred *original_cred;
c7b9a459 N	133	char *dname = clp->cl_recdir;
c7b9a459 N	134	struct dentry *dentry;
c7b9a459 N	135	int status;
	136
	137	dprintk("NFSD: nfsd4_create_clid_dir for \"%s\"\n", dname);
	138
	139	if (!rec_dir_init \|\| clp->cl_firststate)
	140	return 0;
	141
d84f4f99 DH	142	status = nfs4_save_creds(&original_cred);
	143	if (status < 0)
	144	return status;
c7b9a459 N	145
c7b9a459 N	146	/* lock the parent */
a63bb996	147	mutex_lock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459	148
a63bb996	149	dentry = lookup_one_len(dname, rec_dir.dentry, HEXDIR_LEN-1);
c7b9a459 N	150	if (IS_ERR(dentry)) {
	151	status = PTR_ERR(dentry);
	152	goto out_unlock;
	153	}
	154	status = -EEXIST;
	155	if (dentry->d_inode) {
	156	dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
	157	goto out_put;
	158	}
a63bb996	159	status = mnt_want_write(rec_dir.mnt);
463c3197 DH	160	if (status)
463c3197 DH	161	goto out_put;
a63bb996 AV	162	status = vfs_mkdir(rec_dir.dentry->d_inode, dentry, S_IRWXU);
a63bb996 AV	163	mnt_drop_write(rec_dir.mnt);
c7b9a459 N	164	out_put:
	165	dput(dentry);
	166	out_unlock:
a63bb996	167	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	168	if (status == 0) {
c7b9a459 N	169	clp->cl_firststate = 1;
a6ccbbb8	170	nfsd4_sync_rec_dir();
c7b9a459	171	}
d84f4f99	172	nfs4_reset_creds(original_cred);
c7b9a459 N	173	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	174	return status;
	175	}
	176
190e4fbf N	177	typedef int (recdir_func)(struct dentry , struct dentry );
190e4fbf N	178
05f4f678 BF	179	struct name_list {
05f4f678 BF	180	char name[HEXDIR_LEN];
190e4fbf N	181	struct list_head list;
	182	};
	183
190e4fbf	184	static int
05f4f678	185	nfsd4_build_namelist(void arg, const char name, int namlen,
afefdbb2	186	loff_t offset, u64 ino, unsigned int d_type)
190e4fbf	187	{
05f4f678 BF	188	struct list_head *names = arg;
05f4f678 BF	189	struct name_list *entry;
190e4fbf	190
05f4f678	191	if (namlen != HEXDIR_LEN - 1)
b37ad28b	192	return 0;
05f4f678 BF	193	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
05f4f678 BF	194	if (entry == NULL)
190e4fbf	195	return -ENOMEM;
05f4f678 BF	196	memcpy(entry->name, name, HEXDIR_LEN - 1);
	197	entry->name[HEXDIR_LEN - 1] = '\0';
	198	list_add(&entry->list, names);
190e4fbf N	199	return 0;
	200	}
	201
	202	static int
	203	nfsd4_list_rec_dir(struct dentry dir, recdir_func f)
	204	{
d84f4f99	205	const struct cred *original_cred;
190e4fbf	206	struct file *filp;
05f4f678 BF	207	LIST_HEAD(names);
	208	struct name_list *entry;
	209	struct dentry *dentry;
190e4fbf N	210	int status;
	211
	212	if (!rec_dir_init)
	213	return 0;
	214
d84f4f99 DH	215	status = nfs4_save_creds(&original_cred);
	216	if (status < 0)
	217	return status;
190e4fbf	218
745ca247 DH	219	filp = dentry_open(dget(dir), mntget(rec_dir.mnt), O_RDONLY,
745ca247 DH	220	current_cred());
190e4fbf N	221	status = PTR_ERR(filp);
	222	if (IS_ERR(filp))
	223	goto out;
05f4f678	224	status = vfs_readdir(filp, nfsd4_build_namelist, &names);
190e4fbf	225	fput(filp);
8daed1e5	226	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678 BF	227	while (!list_empty(&names)) {
	228	entry = list_entry(names.next, struct name_list, list);
	229
	230	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	231	if (IS_ERR(dentry)) {
	232	status = PTR_ERR(dentry);
2f9092e1	233	break;
05f4f678 BF	234	}
	235	status = f(dir, dentry);
	236	dput(dentry);
190e4fbf	237	if (status)
2f9092e1	238	break;
05f4f678 BF	239	list_del(&entry->list);
05f4f678 BF	240	kfree(entry);
190e4fbf	241	}
2f9092e1	242	mutex_unlock(&dir->d_inode->i_mutex);
190e4fbf	243	out:
05f4f678 BF	244	while (!list_empty(&names)) {
	245	entry = list_entry(names.next, struct name_list, list);
	246	list_del(&entry->list);
	247	kfree(entry);
190e4fbf	248	}
d84f4f99	249	nfs4_reset_creds(original_cred);
190e4fbf N	250	return status;
	251	}
	252
c7b9a459 N	253	static int
	254	nfsd4_unlink_clid_dir(char *name, int namlen)
	255	{
	256	struct dentry *dentry;
	257	int status;
	258
	259	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	260
8daed1e5	261	mutex_lock_nested(&rec_dir.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
a63bb996	262	dentry = lookup_one_len(name, rec_dir.dentry, namlen);
c7b9a459 N	263	if (IS_ERR(dentry)) {
c7b9a459 N	264	status = PTR_ERR(dentry);
2f9092e1	265	goto out_unlock;
c7b9a459 N	266	}
	267	status = -ENOENT;
	268	if (!dentry->d_inode)
	269	goto out;
2f9092e1	270	status = vfs_rmdir(rec_dir.dentry->d_inode, dentry);
c7b9a459 N	271	out:
c7b9a459 N	272	dput(dentry);
2f9092e1 DW	273	out_unlock:
2f9092e1 DW	274	mutex_unlock(&rec_dir.dentry->d_inode->i_mutex);
c7b9a459 N	275	return status;
	276	}
	277
	278	void
	279	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	280	{
d84f4f99	281	const struct cred *original_cred;
c7b9a459 N	282	int status;
	283
	284	if (!rec_dir_init \|\| !clp->cl_firststate)
	285	return;
	286
a63bb996	287	status = mnt_want_write(rec_dir.mnt);
0622753b DH	288	if (status)
0622753b DH	289	goto out;
67be4313	290	clp->cl_firststate = 0;
d84f4f99 DH	291
	292	status = nfs4_save_creds(&original_cred);
	293	if (status < 0)
	294	goto out;
	295
c7b9a459	296	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	297	nfs4_reset_creds(original_cred);
c7b9a459	298	if (status == 0)
a6ccbbb8	299	nfsd4_sync_rec_dir();
a63bb996	300	mnt_drop_write(rec_dir.mnt);
0622753b	301	out:
c7b9a459 N	302	if (status)
	303	printk("NFSD: Failed to remove expired client state directory"
	304	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	305	return;
	306	}
	307
	308	static int
	309	purge_old(struct dentry parent, struct dentry child)
	310	{
	311	int status;
	312
a1bcecd2 AA	313	/* note: we currently use this path only for minorversion 0 */
a1bcecd2 AA	314	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	315	return 0;
c7b9a459	316
2f9092e1	317	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	318	if (status)
	319	printk("failed to remove client recovery directory %s\n",
	320	child->d_name.name);
	321	/* Keep trying, success or failure: */
b37ad28b	322	return 0;
c7b9a459 N	323	}
	324
	325	void
	326	nfsd4_recdir_purge_old(void) {
	327	int status;
	328
	329	if (!rec_dir_init)
	330	return;
a63bb996	331	status = mnt_want_write(rec_dir.mnt);
0622753b DH	332	if (status)
0622753b DH	333	goto out;
a63bb996	334	status = nfsd4_list_rec_dir(rec_dir.dentry, purge_old);
c7b9a459	335	if (status == 0)
a6ccbbb8	336	nfsd4_sync_rec_dir();
a63bb996	337	mnt_drop_write(rec_dir.mnt);
0622753b	338	out:
c7b9a459 N	339	if (status)
c7b9a459 N	340	printk("nfsd4: failed to purge old clients from recovery"
a63bb996	341	" directory %s\n", rec_dir.dentry->d_name.name);
c7b9a459 N	342	}
c7b9a459 N	343
190e4fbf N	344	static int
	345	load_recdir(struct dentry parent, struct dentry child)
	346	{
	347	if (child->d_name.len != HEXDIR_LEN - 1) {
	348	printk("nfsd4: illegal name %s in recovery directory\n",
	349	child->d_name.name);
	350	/* Keep trying; maybe the others are OK: */
b37ad28b	351	return 0;
190e4fbf N	352	}
190e4fbf N	353	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	354	return 0;
190e4fbf N	355	}
	356
	357	int
	358	nfsd4_recdir_load(void) {
	359	int status;
	360
a63bb996	361	status = nfsd4_list_rec_dir(rec_dir.dentry, load_recdir);
190e4fbf N	362	if (status)
190e4fbf N	363	printk("nfsd4: failed loading clients from recovery"
a63bb996	364	" directory %s\n", rec_dir.dentry->d_name.name);
190e4fbf N	365	return status;
	366	}
	367
	368	/*
	369	* Hold reference to the recovery directory.
	370	*/
	371
	372	void
	373	nfsd4_init_recdir(char *rec_dirname)
	374	{
d84f4f99 DH	375	const struct cred *original_cred;
d84f4f99 DH	376	int status;
190e4fbf N	377
	378	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
	379	rec_dirname);
	380
	381	BUG_ON(rec_dir_init);
	382
d84f4f99 DH	383	status = nfs4_save_creds(&original_cred);
	384	if (status < 0) {
	385	printk("NFSD: Unable to change credentials to find recovery"
	386	" directory: error %d\n",
	387	status);
	388	return;
	389	}
190e4fbf	390
a63bb996	391	status = kern_path(rec_dirname, LOOKUP_FOLLOW \| LOOKUP_DIRECTORY,
c2642ab0 BF	392	&rec_dir);
	393	if (status)
	394	printk("NFSD: unable to find recovery directory %s\n",
190e4fbf N	395	rec_dirname);
	396
	397	if (!status)
	398	rec_dir_init = 1;
d84f4f99	399	nfs4_reset_creds(original_cred);
190e4fbf N	400	}
	401
	402	void
	403	nfsd4_shutdown_recdir(void)
	404	{
	405	if (!rec_dir_init)
	406	return;
	407	rec_dir_init = 0;
a63bb996	408	path_put(&rec_dir);
190e4fbf	409	}