[mirror_ubuntu-bionic-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 file *rec_file;

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;
}

int
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 (!rec_file || clp->cl_firststate)
		return 0;

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

	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;
	}
	status = -EEXIST;
	if (dentry->d_inode) {
		dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
		goto out_put;
	}
	status = mnt_want_write(rec_file->f_path.mnt);
	if (status)
		goto out_put;
	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
	mnt_drop_write(rec_file->f_path.mnt);
out_put:
	dput(dentry);
out_unlock:
	mutex_unlock(&dir->d_inode->i_mutex);
	if (status == 0) {
		clp->cl_firststate = 1;
		vfs_fsync(rec_file, 0);
	}
	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(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(rec_file->f_path.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)
		vfs_fsync(rec_file, 0);
	mnt_drop_write(rec_file->f_path.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;

	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(rec_file->f_path.mnt);
	if (status)
		goto out;
	status = nfsd4_list_rec_dir(purge_old);
	if (status == 0)
		vfs_fsync(rec_file, 0);
	mnt_drop_write(rec_file->f_path.mnt);
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(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_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(rec_dirname, O_RDONLY | O_DIRECTORY, 0);
	if (IS_ERR(rec_file)) {
		printk("NFSD: unable to find recovery directory %s\n",
				rec_dirname);
		rec_file = NULL;
	}

	nfs4_reset_creds(original_cred);
}

void
nfsd4_shutdown_recdir(void)
{
	if (!rec_file)
		return;
	fput(rec_file);
	rec_file = NULL;
}
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;
190e4fbf	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
c7b9a459 N	119	int
	120	nfsd4_create_clid_dir(struct nfs4_client *clp)
	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
e970a573	129	if (!rec_file \|\| clp->cl_firststate)
c7b9a459 N	130	return 0;
c7b9a459 N	131
d84f4f99 DH	132	status = nfs4_save_creds(&original_cred);
	133	if (status < 0)
	134	return status;
c7b9a459	135
e970a573	136	dir = rec_file->f_path.dentry;
c7b9a459	137	/* lock the parent */
e970a573	138	mutex_lock(&dir->d_inode->i_mutex);
c7b9a459	139
e970a573	140	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
c7b9a459 N	141	if (IS_ERR(dentry)) {
	142	status = PTR_ERR(dentry);
	143	goto out_unlock;
	144	}
	145	status = -EEXIST;
	146	if (dentry->d_inode) {
	147	dprintk("NFSD: nfsd4_create_clid_dir: DIRECTORY EXISTS\n");
	148	goto out_put;
	149	}
e970a573	150	status = mnt_want_write(rec_file->f_path.mnt);
463c3197 DH	151	if (status)
463c3197 DH	152	goto out_put;
e970a573 CH	153	status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU);
e970a573 CH	154	mnt_drop_write(rec_file->f_path.mnt);
c7b9a459 N	155	out_put:
	156	dput(dentry);
	157	out_unlock:
e970a573	158	mutex_unlock(&dir->d_inode->i_mutex);
c7b9a459 N	159	if (status == 0) {
c7b9a459 N	160	clp->cl_firststate = 1;
8018ab05	161	vfs_fsync(rec_file, 0);
c7b9a459	162	}
d84f4f99	163	nfs4_reset_creds(original_cred);
c7b9a459 N	164	dprintk("NFSD: nfsd4_create_clid_dir returns %d\n", status);
	165	return status;
	166	}
	167
190e4fbf N	168	typedef int (recdir_func)(struct dentry , struct dentry );
190e4fbf N	169
05f4f678 BF	170	struct name_list {
05f4f678 BF	171	char name[HEXDIR_LEN];
190e4fbf N	172	struct list_head list;
	173	};
	174
190e4fbf	175	static int
05f4f678	176	nfsd4_build_namelist(void arg, const char name, int namlen,
afefdbb2	177	loff_t offset, u64 ino, unsigned int d_type)
190e4fbf	178	{
05f4f678 BF	179	struct list_head *names = arg;
05f4f678 BF	180	struct name_list *entry;
190e4fbf	181
05f4f678	182	if (namlen != HEXDIR_LEN - 1)
b37ad28b	183	return 0;
05f4f678 BF	184	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
05f4f678 BF	185	if (entry == NULL)
190e4fbf	186	return -ENOMEM;
05f4f678 BF	187	memcpy(entry->name, name, HEXDIR_LEN - 1);
	188	entry->name[HEXDIR_LEN - 1] = '\0';
	189	list_add(&entry->list, names);
190e4fbf N	190	return 0;
	191	}
	192
	193	static int
5b4b299c	194	nfsd4_list_rec_dir(recdir_func *f)
190e4fbf	195	{
d84f4f99	196	const struct cred *original_cred;
5b4b299c	197	struct dentry *dir = rec_file->f_path.dentry;
05f4f678	198	LIST_HEAD(names);
190e4fbf N	199	int status;
190e4fbf N	200
d84f4f99 DH	201	status = nfs4_save_creds(&original_cred);
	202	if (status < 0)
	203	return status;
190e4fbf	204
5b4b299c AV	205	status = vfs_llseek(rec_file, 0, SEEK_SET);
	206	if (status < 0) {
	207	nfs4_reset_creds(original_cred);
	208	return status;
	209	}
	210
	211	status = vfs_readdir(rec_file, nfsd4_build_namelist, &names);
8daed1e5	212	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
05f4f678	213	while (!list_empty(&names)) {
5b4b299c	214	struct name_list *entry;
05f4f678	215	entry = list_entry(names.next, struct name_list, list);
5b4b299c AV	216	if (!status) {
	217	struct dentry *dentry;
	218	dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
	219	if (IS_ERR(dentry)) {
	220	status = PTR_ERR(dentry);
	221	break;
	222	}
	223	status = f(dir, dentry);
	224	dput(dentry);
05f4f678	225	}
05f4f678 BF	226	list_del(&entry->list);
05f4f678 BF	227	kfree(entry);
190e4fbf	228	}
2f9092e1	229	mutex_unlock(&dir->d_inode->i_mutex);
d84f4f99	230	nfs4_reset_creds(original_cred);
190e4fbf N	231	return status;
	232	}
	233
c7b9a459 N	234	static int
	235	nfsd4_unlink_clid_dir(char *name, int namlen)
	236	{
e970a573	237	struct dentry dir, dentry;
c7b9a459 N	238	int status;
	239
	240	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
	241
e970a573 CH	242	dir = rec_file->f_path.dentry;
	243	mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT);
	244	dentry = lookup_one_len(name, dir, namlen);
c7b9a459 N	245	if (IS_ERR(dentry)) {
c7b9a459 N	246	status = PTR_ERR(dentry);
2f9092e1	247	goto out_unlock;
c7b9a459 N	248	}
	249	status = -ENOENT;
	250	if (!dentry->d_inode)
	251	goto out;
e970a573	252	status = vfs_rmdir(dir->d_inode, dentry);
c7b9a459 N	253	out:
c7b9a459 N	254	dput(dentry);
2f9092e1	255	out_unlock:
e970a573	256	mutex_unlock(&dir->d_inode->i_mutex);
c7b9a459 N	257	return status;
	258	}
	259
	260	void
	261	nfsd4_remove_clid_dir(struct nfs4_client *clp)
	262	{
d84f4f99	263	const struct cred *original_cred;
c7b9a459 N	264	int status;
c7b9a459 N	265
e970a573	266	if (!rec_file \|\| !clp->cl_firststate)
c7b9a459 N	267	return;
c7b9a459 N	268
e970a573	269	status = mnt_want_write(rec_file->f_path.mnt);
0622753b DH	270	if (status)
0622753b DH	271	goto out;
67be4313	272	clp->cl_firststate = 0;
d84f4f99 DH	273
	274	status = nfs4_save_creds(&original_cred);
	275	if (status < 0)
	276	goto out;
	277
c7b9a459	278	status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
d84f4f99	279	nfs4_reset_creds(original_cred);
c7b9a459	280	if (status == 0)
8018ab05	281	vfs_fsync(rec_file, 0);
e970a573	282	mnt_drop_write(rec_file->f_path.mnt);
0622753b	283	out:
c7b9a459 N	284	if (status)
	285	printk("NFSD: Failed to remove expired client state directory"
	286	" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
	287	return;
	288	}
	289
	290	static int
	291	purge_old(struct dentry parent, struct dentry child)
	292	{
	293	int status;
	294
a1bcecd2	295	if (nfs4_has_reclaimed_state(child->d_name.name, false))
b37ad28b	296	return 0;
c7b9a459	297
2f9092e1	298	status = vfs_rmdir(parent->d_inode, child);
c7b9a459 N	299	if (status)
	300	printk("failed to remove client recovery directory %s\n",
	301	child->d_name.name);
	302	/* Keep trying, success or failure: */
b37ad28b	303	return 0;
c7b9a459 N	304	}
	305
	306	void
	307	nfsd4_recdir_purge_old(void) {
	308	int status;
	309
e970a573	310	if (!rec_file)
c7b9a459	311	return;
e970a573	312	status = mnt_want_write(rec_file->f_path.mnt);
0622753b DH	313	if (status)
0622753b DH	314	goto out;
5b4b299c	315	status = nfsd4_list_rec_dir(purge_old);
c7b9a459	316	if (status == 0)
8018ab05	317	vfs_fsync(rec_file, 0);
e970a573	318	mnt_drop_write(rec_file->f_path.mnt);
0622753b	319	out:
c7b9a459 N	320	if (status)
c7b9a459 N	321	printk("nfsd4: failed to purge old clients from recovery"
e970a573	322	" directory %s\n", rec_file->f_path.dentry->d_name.name);
c7b9a459 N	323	}
c7b9a459 N	324
190e4fbf N	325	static int
	326	load_recdir(struct dentry parent, struct dentry child)
	327	{
	328	if (child->d_name.len != HEXDIR_LEN - 1) {
	329	printk("nfsd4: illegal name %s in recovery directory\n",
	330	child->d_name.name);
	331	/* Keep trying; maybe the others are OK: */
b37ad28b	332	return 0;
190e4fbf N	333	}
190e4fbf N	334	nfs4_client_to_reclaim(child->d_name.name);
b37ad28b	335	return 0;
190e4fbf N	336	}
	337
	338	int
	339	nfsd4_recdir_load(void) {
	340	int status;
	341
e970a573 CH	342	if (!rec_file)
	343	return 0;
	344
5b4b299c	345	status = nfsd4_list_rec_dir(load_recdir);
190e4fbf N	346	if (status)
190e4fbf N	347	printk("nfsd4: failed loading clients from recovery"
e970a573	348	" directory %s\n", rec_file->f_path.dentry->d_name.name);
190e4fbf N	349	return status;
	350	}
	351
	352	/*
	353	* Hold reference to the recovery directory.
	354	*/
	355
	356	void
	357	nfsd4_init_recdir(char *rec_dirname)
	358	{
d84f4f99 DH	359	const struct cred *original_cred;
d84f4f99 DH	360	int status;
190e4fbf N	361
	362	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
	363	rec_dirname);
	364
e970a573	365	BUG_ON(rec_file);
190e4fbf	366
d84f4f99 DH	367	status = nfs4_save_creds(&original_cred);
	368	if (status < 0) {
	369	printk("NFSD: Unable to change credentials to find recovery"
	370	" directory: error %d\n",
	371	status);
	372	return;
	373	}
190e4fbf	374
e970a573 CH	375	rec_file = filp_open(rec_dirname, O_RDONLY \| O_DIRECTORY, 0);
e970a573 CH	376	if (IS_ERR(rec_file)) {
c2642ab0	377	printk("NFSD: unable to find recovery directory %s\n",
190e4fbf	378	rec_dirname);
e970a573 CH	379	rec_file = NULL;
e970a573 CH	380	}
190e4fbf	381
d84f4f99	382	nfs4_reset_creds(original_cred);
190e4fbf N	383	}
	384
	385	void
	386	nfsd4_shutdown_recdir(void)
	387	{
e970a573	388	if (!rec_file)
190e4fbf	389	return;
e970a573 CH	390	fput(rec_file);
e970a573 CH	391	rec_file = NULL;
190e4fbf	392	}