1/*
   2*  Copyright (c) 2004 The Regents of the University of Michigan.
   3*  Copyright (c) 2012 Jeff Layton <jlayton@redhat.com>
   4*  All rights reserved.
   5*
   6*  Andy Adamson <andros@citi.umich.edu>
   7*
   8*  Redistribution and use in source and binary forms, with or without
   9*  modification, are permitted provided that the following conditions
  10*  are met:
  11*
  12*  1. Redistributions of source code must retain the above copyright
  13*     notice, this list of conditions and the following disclaimer.
  14*  2. Redistributions in binary form must reproduce the above copyright
  15*     notice, this list of conditions and the following disclaimer in the
  16*     documentation and/or other materials provided with the distribution.
  17*  3. Neither the name of the University nor the names of its
  18*     contributors may be used to endorse or promote products derived
  19*     from this software without specific prior written permission.
  20*
  21*  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  22*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  23*  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  24*  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25*  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  26*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  27*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  28*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  29*  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  30*  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  31*  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32*
  33*/
  34
  35#include <crypto/hash.h>
  36#include <linux/file.h>
  37#include <linux/slab.h>
  38#include <linux/namei.h>
 
  39#include <linux/sched.h>
  40#include <linux/fs.h>
  41#include <linux/module.h>
  42#include <net/net_namespace.h>
  43#include <linux/sunrpc/rpc_pipe_fs.h>
  44#include <linux/sunrpc/clnt.h>
  45#include <linux/nfsd/cld.h>
  46
  47#include "nfsd.h"
  48#include "state.h"
  49#include "vfs.h"
  50#include "netns.h"
  51
  52#define NFSDDBG_FACILITY                NFSDDBG_PROC
  53
  54/* Declarations */
  55struct nfsd4_client_tracking_ops {
  56	int (*init)(struct net *);
  57	void (*exit)(struct net *);
  58	void (*create)(struct nfs4_client *);
  59	void (*remove)(struct nfs4_client *);
  60	int (*check)(struct nfs4_client *);
  61	void (*grace_done)(struct nfsd_net *);
  62	uint8_t version;
  63	size_t msglen;
  64};
  65
  66static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops;
  67static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2;
  68
  69#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
  70/* Globals */
 
  71static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery";
 
  72
  73static int
  74nfs4_save_creds(const struct cred **original_creds)
  75{
  76	struct cred *new;
  77
  78	new = prepare_creds();
  79	if (!new)
  80		return -ENOMEM;
  81
  82	new->fsuid = GLOBAL_ROOT_UID;
  83	new->fsgid = GLOBAL_ROOT_GID;
  84	*original_creds = override_creds(new);
  85	put_cred(new);
  86	return 0;
  87}
  88
  89static void
  90nfs4_reset_creds(const struct cred *original)
  91{
  92	revert_creds(original);
  93}
  94
  95static void
  96md5_to_hex(char *out, char *md5)
  97{
  98	int i;
  99
 100	for (i=0; i<16; i++) {
 101		unsigned char c = md5[i];
 102
 103		*out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
 104		*out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
 105	}
 106	*out = '\0';
 107}
 108
 109static int
 110nfs4_make_rec_clidname(char *dname, const struct xdr_netobj *clname)
 111{
 112	struct xdr_netobj cksum;
 113	struct crypto_shash *tfm;
 114	int status;
 
 115
 116	dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
 117			clname->len, clname->data);
 118	tfm = crypto_alloc_shash("md5", 0, 0);
 119	if (IS_ERR(tfm)) {
 120		status = PTR_ERR(tfm);
 121		goto out_no_tfm;
 122	}
 123
 124	cksum.len = crypto_shash_digestsize(tfm);
 125	cksum.data = kmalloc(cksum.len, GFP_KERNEL);
 126	if (cksum.data == NULL) {
 127		status = -ENOMEM;
 128 		goto out;
 129	}
 130
 131	status = crypto_shash_tfm_digest(tfm, clname->data, clname->len,
 132					 cksum.data);
 133	if (status)
 134		goto out;
 135
 136	md5_to_hex(dname, cksum.data);
 137
 138	status = 0;
 139out:
 140	kfree(cksum.data);
 141	crypto_free_shash(tfm);
 142out_no_tfm:
 143	return status;
 144}
 145
 146/*
 147 * If we had an error generating the recdir name for the legacy tracker
 148 * then warn the admin. If the error doesn't appear to be transient,
 149 * then disable recovery tracking.
 150 */
 151static void
 152legacy_recdir_name_error(struct nfs4_client *clp, int error)
 153{
 154	printk(KERN_ERR "NFSD: unable to generate recoverydir "
 155			"name (%d).\n", error);
 156
 157	/*
 158	 * if the algorithm just doesn't exist, then disable the recovery
 159	 * tracker altogether. The crypto libs will generally return this if
 160	 * FIPS is enabled as well.
 161	 */
 162	if (error == -ENOENT) {
 163		printk(KERN_ERR "NFSD: disabling legacy clientid tracking. "
 164			"Reboot recovery will not function correctly!\n");
 165		nfsd4_client_tracking_exit(clp->net);
 166	}
 167}
 168
 169static void
 170__nfsd4_create_reclaim_record_grace(struct nfs4_client *clp,
 171		const char *dname, int len, struct nfsd_net *nn)
 172{
 173	struct xdr_netobj name;
 174	struct xdr_netobj princhash = { .len = 0, .data = NULL };
 175	struct nfs4_client_reclaim *crp;
 176
 177	name.data = kmemdup(dname, len, GFP_KERNEL);
 178	if (!name.data) {
 179		dprintk("%s: failed to allocate memory for name.data!\n",
 180			__func__);
 181		return;
 182	}
 183	name.len = len;
 184	crp = nfs4_client_to_reclaim(name, princhash, nn);
 185	if (!crp) {
 186		kfree(name.data);
 187		return;
 188	}
 189	crp->cr_clp = clp;
 190}
 191
 192static void
 193nfsd4_create_clid_dir(struct nfs4_client *clp)
 194{
 195	const struct cred *original_cred;
 196	char dname[HEXDIR_LEN];
 197	struct dentry *dir, *dentry;
 198	int status;
 199	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
 200
 201	if (test_and_set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 202		return;
 203	if (!nn->rec_file)
 204		return;
 205
 206	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 207	if (status)
 208		return legacy_recdir_name_error(clp, status);
 209
 210	status = nfs4_save_creds(&original_cred);
 211	if (status < 0)
 212		return;
 213
 214	status = mnt_want_write_file(nn->rec_file);
 215	if (status)
 216		goto out_creds;
 217
 218	dir = nn->rec_file->f_path.dentry;
 219	/* lock the parent */
 220	inode_lock(d_inode(dir));
 221
 222	dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1);
 223	if (IS_ERR(dentry)) {
 224		status = PTR_ERR(dentry);
 225		goto out_unlock;
 226	}
 227	if (d_really_is_positive(dentry))
 228		/*
 229		 * In the 4.1 case, where we're called from
 230		 * reclaim_complete(), records from the previous reboot
 231		 * may still be left, so this is OK.
 232		 *
 233		 * In the 4.0 case, we should never get here; but we may
 234		 * as well be forgiving and just succeed silently.
 235		 */
 236		goto out_put;
 237	status = vfs_mkdir(&nop_mnt_idmap, d_inode(dir), dentry, S_IRWXU);
 
 
 
 
 238out_put:
 239	dput(dentry);
 240out_unlock:
 241	inode_unlock(d_inode(dir));
 242	if (status == 0) {
 243		if (nn->in_grace)
 244			__nfsd4_create_reclaim_record_grace(clp, dname,
 245					HEXDIR_LEN, nn);
 246		vfs_fsync(nn->rec_file, 0);
 247	} else {
 248		printk(KERN_ERR "NFSD: failed to write recovery record"
 249				" (err %d); please check that %s exists"
 250				" and is writeable", status,
 251				user_recovery_dirname);
 252	}
 253	mnt_drop_write_file(nn->rec_file);
 254out_creds:
 255	nfs4_reset_creds(original_cred);
 256}
 257
 258typedef int (recdir_func)(struct dentry *, struct dentry *, struct nfsd_net *);
 259
 260struct name_list {
 261	char name[HEXDIR_LEN];
 262	struct list_head list;
 263};
 264
 265struct nfs4_dir_ctx {
 266	struct dir_context ctx;
 267	struct list_head names;
 268};
 269
 270static bool
 271nfsd4_build_namelist(struct dir_context *__ctx, const char *name, int namlen,
 272		loff_t offset, u64 ino, unsigned int d_type)
 273{
 274	struct nfs4_dir_ctx *ctx =
 275		container_of(__ctx, struct nfs4_dir_ctx, ctx);
 276	struct name_list *entry;
 277
 278	if (namlen != HEXDIR_LEN - 1)
 279		return true;
 280	entry = kmalloc(sizeof(struct name_list), GFP_KERNEL);
 281	if (entry == NULL)
 282		return false;
 283	memcpy(entry->name, name, HEXDIR_LEN - 1);
 284	entry->name[HEXDIR_LEN - 1] = '\0';
 285	list_add(&entry->list, &ctx->names);
 286	return true;
 287}
 288
 289static int
 290nfsd4_list_rec_dir(recdir_func *f, struct nfsd_net *nn)
 291{
 292	const struct cred *original_cred;
 293	struct dentry *dir = nn->rec_file->f_path.dentry;
 294	struct nfs4_dir_ctx ctx = {
 295		.ctx.actor = nfsd4_build_namelist,
 296		.names = LIST_HEAD_INIT(ctx.names)
 297	};
 298	struct name_list *entry, *tmp;
 299	int status;
 300
 301	status = nfs4_save_creds(&original_cred);
 302	if (status < 0)
 303		return status;
 304
 305	status = vfs_llseek(nn->rec_file, 0, SEEK_SET);
 306	if (status < 0) {
 307		nfs4_reset_creds(original_cred);
 308		return status;
 309	}
 310
 311	status = iterate_dir(nn->rec_file, &ctx.ctx);
 312	inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
 313
 314	list_for_each_entry_safe(entry, tmp, &ctx.names, list) {
 
 315		if (!status) {
 316			struct dentry *dentry;
 317			dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1);
 318			if (IS_ERR(dentry)) {
 319				status = PTR_ERR(dentry);
 320				break;
 321			}
 322			status = f(dir, dentry, nn);
 323			dput(dentry);
 324		}
 325		list_del(&entry->list);
 326		kfree(entry);
 327	}
 328	inode_unlock(d_inode(dir));
 329	nfs4_reset_creds(original_cred);
 330
 331	list_for_each_entry_safe(entry, tmp, &ctx.names, list) {
 332		dprintk("NFSD: %s. Left entry %s\n", __func__, entry->name);
 333		list_del(&entry->list);
 334		kfree(entry);
 335	}
 336	return status;
 337}
 338
 339static int
 340nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn)
 341{
 342	struct dentry *dir, *dentry;
 343	int status;
 344
 345	dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name);
 346
 347	dir = nn->rec_file->f_path.dentry;
 348	inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
 349	dentry = lookup_one_len(name, dir, namlen);
 350	if (IS_ERR(dentry)) {
 351		status = PTR_ERR(dentry);
 352		goto out_unlock;
 353	}
 354	status = -ENOENT;
 355	if (d_really_is_negative(dentry))
 356		goto out;
 357	status = vfs_rmdir(&nop_mnt_idmap, d_inode(dir), dentry);
 358out:
 359	dput(dentry);
 360out_unlock:
 361	inode_unlock(d_inode(dir));
 362	return status;
 363}
 364
 365static void
 366__nfsd4_remove_reclaim_record_grace(const char *dname, int len,
 367		struct nfsd_net *nn)
 368{
 369	struct xdr_netobj name;
 370	struct nfs4_client_reclaim *crp;
 371
 372	name.data = kmemdup(dname, len, GFP_KERNEL);
 373	if (!name.data) {
 374		dprintk("%s: failed to allocate memory for name.data!\n",
 375			__func__);
 376		return;
 377	}
 378	name.len = len;
 379	crp = nfsd4_find_reclaim_client(name, nn);
 380	kfree(name.data);
 381	if (crp)
 382		nfs4_remove_reclaim_record(crp, nn);
 383}
 384
 385static void
 386nfsd4_remove_clid_dir(struct nfs4_client *clp)
 387{
 388	const struct cred *original_cred;
 389	char dname[HEXDIR_LEN];
 390	int status;
 391	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 392
 393	if (!nn->rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 394		return;
 395
 396	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 397	if (status)
 398		return legacy_recdir_name_error(clp, status);
 399
 400	status = mnt_want_write_file(nn->rec_file);
 401	if (status)
 402		goto out;
 403	clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 404
 405	status = nfs4_save_creds(&original_cred);
 406	if (status < 0)
 407		goto out_drop_write;
 408
 409	status = nfsd4_unlink_clid_dir(dname, HEXDIR_LEN-1, nn);
 410	nfs4_reset_creds(original_cred);
 411	if (status == 0) {
 412		vfs_fsync(nn->rec_file, 0);
 413		if (nn->in_grace)
 414			__nfsd4_remove_reclaim_record_grace(dname,
 415					HEXDIR_LEN, nn);
 416	}
 417out_drop_write:
 418	mnt_drop_write_file(nn->rec_file);
 419out:
 420	if (status)
 421		printk("NFSD: Failed to remove expired client state directory"
 422				" %.*s\n", HEXDIR_LEN, dname);
 423}
 424
 425static int
 426purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 427{
 428	int status;
 429	struct xdr_netobj name;
 430
 431	if (child->d_name.len != HEXDIR_LEN - 1) {
 432		printk("%s: illegal name %pd in recovery directory\n",
 433				__func__, child);
 434		/* Keep trying; maybe the others are OK: */
 435		return 0;
 436	}
 437	name.data = kmemdup_nul(child->d_name.name, child->d_name.len, GFP_KERNEL);
 438	if (!name.data) {
 439		dprintk("%s: failed to allocate memory for name.data!\n",
 440			__func__);
 441		goto out;
 442	}
 443	name.len = HEXDIR_LEN;
 444	if (nfs4_has_reclaimed_state(name, nn))
 445		goto out_free;
 446
 447	status = vfs_rmdir(&nop_mnt_idmap, d_inode(parent), child);
 448	if (status)
 449		printk("failed to remove client recovery directory %pd\n",
 450				child);
 451out_free:
 452	kfree(name.data);
 453out:
 454	/* Keep trying, success or failure: */
 455	return 0;
 456}
 457
 458static void
 459nfsd4_recdir_purge_old(struct nfsd_net *nn)
 460{
 461	int status;
 462
 463	nn->in_grace = false;
 464	if (!nn->rec_file)
 465		return;
 466	status = mnt_want_write_file(nn->rec_file);
 467	if (status)
 468		goto out;
 469	status = nfsd4_list_rec_dir(purge_old, nn);
 470	if (status == 0)
 471		vfs_fsync(nn->rec_file, 0);
 472	mnt_drop_write_file(nn->rec_file);
 473out:
 474	nfs4_release_reclaim(nn);
 475	if (status)
 476		printk("nfsd4: failed to purge old clients from recovery"
 477			" directory %pD\n", nn->rec_file);
 478}
 479
 480static int
 481load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
 482{
 483	struct xdr_netobj name;
 484	struct xdr_netobj princhash = { .len = 0, .data = NULL };
 485
 486	if (child->d_name.len != HEXDIR_LEN - 1) {
 487		printk("%s: illegal name %pd in recovery directory\n",
 488				__func__, child);
 489		/* Keep trying; maybe the others are OK: */
 490		return 0;
 491	}
 492	name.data = kmemdup_nul(child->d_name.name, child->d_name.len, GFP_KERNEL);
 493	if (!name.data) {
 494		dprintk("%s: failed to allocate memory for name.data!\n",
 495			__func__);
 496		goto out;
 497	}
 498	name.len = HEXDIR_LEN;
 499	if (!nfs4_client_to_reclaim(name, princhash, nn))
 500		kfree(name.data);
 501out:
 502	return 0;
 503}
 504
 505static int
 506nfsd4_recdir_load(struct net *net) {
 507	int status;
 508	struct nfsd_net *nn =  net_generic(net, nfsd_net_id);
 509
 510	if (!nn->rec_file)
 511		return 0;
 512
 513	status = nfsd4_list_rec_dir(load_recdir, nn);
 514	if (status)
 515		printk("nfsd4: failed loading clients from recovery"
 516			" directory %pD\n", nn->rec_file);
 517	return status;
 518}
 519
 520/*
 521 * Hold reference to the recovery directory.
 522 */
 523
 524static int
 525nfsd4_init_recdir(struct net *net)
 526{
 527	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 528	const struct cred *original_cred;
 529	int status;
 530
 531	printk("NFSD: Using %s as the NFSv4 state recovery directory\n",
 532			user_recovery_dirname);
 533
 534	BUG_ON(nn->rec_file);
 535
 536	status = nfs4_save_creds(&original_cred);
 537	if (status < 0) {
 538		printk("NFSD: Unable to change credentials to find recovery"
 539		       " directory: error %d\n",
 540		       status);
 541		return status;
 542	}
 543
 544	nn->rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0);
 545	if (IS_ERR(nn->rec_file)) {
 546		printk("NFSD: unable to find recovery directory %s\n",
 547				user_recovery_dirname);
 548		status = PTR_ERR(nn->rec_file);
 549		nn->rec_file = NULL;
 550	}
 551
 552	nfs4_reset_creds(original_cred);
 553	if (!status)
 554		nn->in_grace = true;
 555	return status;
 556}
 557
 558static void
 559nfsd4_shutdown_recdir(struct net *net)
 560{
 561	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 562
 563	if (!nn->rec_file)
 564		return;
 565	fput(nn->rec_file);
 566	nn->rec_file = NULL;
 567}
 568
 569static int
 570nfs4_legacy_state_init(struct net *net)
 571{
 572	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 573	int i;
 574
 575	nn->reclaim_str_hashtbl = kmalloc_array(CLIENT_HASH_SIZE,
 576						sizeof(struct list_head),
 577						GFP_KERNEL);
 578	if (!nn->reclaim_str_hashtbl)
 579		return -ENOMEM;
 580
 581	for (i = 0; i < CLIENT_HASH_SIZE; i++)
 582		INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]);
 583	nn->reclaim_str_hashtbl_size = 0;
 584
 585	return 0;
 586}
 587
 588static void
 589nfs4_legacy_state_shutdown(struct net *net)
 590{
 591	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 592
 593	kfree(nn->reclaim_str_hashtbl);
 594}
 595
 596static int
 597nfsd4_load_reboot_recovery_data(struct net *net)
 598{
 599	int status;
 600
 601	status = nfsd4_init_recdir(net);
 602	if (status)
 603		return status;
 604
 605	status = nfsd4_recdir_load(net);
 606	if (status)
 607		nfsd4_shutdown_recdir(net);
 608
 609	return status;
 610}
 611
 612static int
 613nfsd4_legacy_tracking_init(struct net *net)
 614{
 615	int status;
 616
 617	/* XXX: The legacy code won't work in a container */
 618	if (net != &init_net) {
 619		pr_warn("NFSD: attempt to initialize legacy client tracking in a container ignored.\n");
 
 620		return -EINVAL;
 621	}
 622
 623	status = nfs4_legacy_state_init(net);
 624	if (status)
 625		return status;
 626
 627	status = nfsd4_load_reboot_recovery_data(net);
 628	if (status)
 629		goto err;
 630	pr_info("NFSD: Using legacy client tracking operations.\n");
 631	return 0;
 632
 633err:
 634	nfs4_legacy_state_shutdown(net);
 635	return status;
 636}
 637
 638static void
 639nfsd4_legacy_tracking_exit(struct net *net)
 640{
 641	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
 
 
 
 642
 643	nfs4_release_reclaim(nn);
 644	nfsd4_shutdown_recdir(net);
 645	nfs4_legacy_state_shutdown(net);
 
 
 646}
 647
 648/*
 649 * Change the NFSv4 recovery directory to recdir.
 650 */
 651int
 652nfs4_reset_recoverydir(char *recdir)
 653{
 654	int status;
 655	struct path path;
 656
 657	status = kern_path(recdir, LOOKUP_FOLLOW, &path);
 658	if (status)
 659		return status;
 660	status = -ENOTDIR;
 661	if (d_is_dir(path.dentry)) {
 662		strscpy(user_recovery_dirname, recdir,
 663			sizeof(user_recovery_dirname));
 664		status = 0;
 665	}
 666	path_put(&path);
 667	return status;
 668}
 669
 670char *
 671nfs4_recoverydir(void)
 672{
 673	return user_recovery_dirname;
 674}
 675
 676static int
 677nfsd4_check_legacy_client(struct nfs4_client *clp)
 678{
 679	int status;
 680	char dname[HEXDIR_LEN];
 681	struct nfs4_client_reclaim *crp;
 682	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 683	struct xdr_netobj name;
 684
 685	/* did we already find that this client is stable? */
 686	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
 687		return 0;
 688
 689	status = nfs4_make_rec_clidname(dname, &clp->cl_name);
 690	if (status) {
 691		legacy_recdir_name_error(clp, status);
 692		return status;
 693	}
 694
 695	/* look for it in the reclaim hashtable otherwise */
 696	name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
 697	if (!name.data) {
 698		dprintk("%s: failed to allocate memory for name.data!\n",
 699			__func__);
 700		goto out_enoent;
 701	}
 702	name.len = HEXDIR_LEN;
 703	crp = nfsd4_find_reclaim_client(name, nn);
 704	kfree(name.data);
 705	if (crp) {
 706		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
 707		crp->cr_clp = clp;
 708		return 0;
 709	}
 710
 711out_enoent:
 712	return -ENOENT;
 713}
 714
 715static const struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = {
 716	.init		= nfsd4_legacy_tracking_init,
 717	.exit		= nfsd4_legacy_tracking_exit,
 718	.create		= nfsd4_create_clid_dir,
 719	.remove		= nfsd4_remove_clid_dir,
 720	.check		= nfsd4_check_legacy_client,
 721	.grace_done	= nfsd4_recdir_purge_old,
 722	.version	= 1,
 723	.msglen		= 0,
 724};
 725#endif /* CONFIG_NFSD_LEGACY_CLIENT_TRACKING */
 726
 727/* Globals */
 728#define NFSD_PIPE_DIR		"nfsd"
 729#define NFSD_CLD_PIPE		"cld"
 730
 731/* per-net-ns structure for holding cld upcall info */
 732struct cld_net {
 733	struct rpc_pipe		*cn_pipe;
 734	spinlock_t		 cn_lock;
 735	struct list_head	 cn_list;
 736	unsigned int		 cn_xid;
 737	struct crypto_shash	*cn_tfm;
 738#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 739	bool			 cn_has_legacy;
 740#endif
 741};
 742
 743struct cld_upcall {
 744	struct list_head	 cu_list;
 745	struct cld_net		*cu_net;
 746	struct completion	 cu_done;
 747	union {
 748		struct cld_msg_hdr	 cu_hdr;
 749		struct cld_msg		 cu_msg;
 750		struct cld_msg_v2	 cu_msg_v2;
 751	} cu_u;
 752};
 753
 754static int
 755__cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg, struct nfsd_net *nn)
 756{
 757	int ret;
 758	struct rpc_pipe_msg msg;
 759	struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, cu_u);
 760
 761	memset(&msg, 0, sizeof(msg));
 762	msg.data = cmsg;
 763	msg.len = nn->client_tracking_ops->msglen;
 764
 
 
 
 
 
 765	ret = rpc_queue_upcall(pipe, &msg);
 766	if (ret < 0) {
 
 767		goto out;
 768	}
 769
 770	wait_for_completion(&cup->cu_done);
 
 771
 772	if (msg.errno < 0)
 773		ret = msg.errno;
 774out:
 775	return ret;
 776}
 777
 778static int
 779cld_pipe_upcall(struct rpc_pipe *pipe, void *cmsg, struct nfsd_net *nn)
 780{
 781	int ret;
 782
 783	/*
 784	 * -EAGAIN occurs when pipe is closed and reopened while there are
 785	 *  upcalls queued.
 786	 */
 787	do {
 788		ret = __cld_pipe_upcall(pipe, cmsg, nn);
 789	} while (ret == -EAGAIN);
 790
 791	return ret;
 792}
 793
 794static ssize_t
 795__cld_pipe_inprogress_downcall(const struct cld_msg_v2 __user *cmsg,
 796		struct nfsd_net *nn)
 797{
 798	uint8_t cmd, princhashlen;
 799	struct xdr_netobj name, princhash = { .len = 0, .data = NULL };
 800	uint16_t namelen;
 801
 802	if (get_user(cmd, &cmsg->cm_cmd)) {
 803		dprintk("%s: error when copying cmd from userspace", __func__);
 804		return -EFAULT;
 805	}
 806	if (cmd == Cld_GraceStart) {
 807		if (nn->client_tracking_ops->version >= 2) {
 808			const struct cld_clntinfo __user *ci;
 809
 810			ci = &cmsg->cm_u.cm_clntinfo;
 811			if (get_user(namelen, &ci->cc_name.cn_len))
 812				return -EFAULT;
 813			if (namelen == 0 || namelen > NFS4_OPAQUE_LIMIT) {
 814				dprintk("%s: invalid namelen (%u)", __func__, namelen);
 815				return -EINVAL;
 816			}
 817			name.data = memdup_user(&ci->cc_name.cn_id, namelen);
 818			if (IS_ERR(name.data))
 819				return PTR_ERR(name.data);
 820			name.len = namelen;
 821			get_user(princhashlen, &ci->cc_princhash.cp_len);
 822			if (princhashlen > 0) {
 823				princhash.data = memdup_user(
 824						&ci->cc_princhash.cp_data,
 825						princhashlen);
 826				if (IS_ERR(princhash.data)) {
 827					kfree(name.data);
 828					return PTR_ERR(princhash.data);
 829				}
 830				princhash.len = princhashlen;
 831			} else
 832				princhash.len = 0;
 833		} else {
 834			const struct cld_name __user *cnm;
 835
 836			cnm = &cmsg->cm_u.cm_name;
 837			if (get_user(namelen, &cnm->cn_len))
 838				return -EFAULT;
 839			if (namelen == 0 || namelen > NFS4_OPAQUE_LIMIT) {
 840				dprintk("%s: invalid namelen (%u)", __func__, namelen);
 841				return -EINVAL;
 842			}
 843			name.data = memdup_user(&cnm->cn_id, namelen);
 844			if (IS_ERR(name.data))
 845				return PTR_ERR(name.data);
 846			name.len = namelen;
 847		}
 848#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
 849		if (name.len > 5 && memcmp(name.data, "hash:", 5) == 0) {
 850			struct cld_net *cn = nn->cld_net;
 851
 852			name.len = name.len - 5;
 853			memmove(name.data, name.data + 5, name.len);
 854			cn->cn_has_legacy = true;
 855		}
 856#endif
 857		if (!nfs4_client_to_reclaim(name, princhash, nn)) {
 858			kfree(name.data);
 859			kfree(princhash.data);
 860			return -EFAULT;
 861		}
 862		return nn->client_tracking_ops->msglen;
 863	}
 864	return -EFAULT;
 865}
 866
 867static ssize_t
 868cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
 869{
 870	struct cld_upcall *tmp, *cup;
 871	struct cld_msg_hdr __user *hdr = (struct cld_msg_hdr __user *)src;
 872	struct cld_msg_v2 __user *cmsg = (struct cld_msg_v2 __user *)src;
 873	uint32_t xid;
 874	struct nfsd_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info,
 875						nfsd_net_id);
 876	struct cld_net *cn = nn->cld_net;
 877	int16_t status;
 878
 879	if (mlen != nn->client_tracking_ops->msglen) {
 880		dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen,
 881			nn->client_tracking_ops->msglen);
 882		return -EINVAL;
 883	}
 884
 885	/* copy just the xid so we can try to find that */
 886	if (copy_from_user(&xid, &hdr->cm_xid, sizeof(xid)) != 0) {
 887		dprintk("%s: error when copying xid from userspace", __func__);
 888		return -EFAULT;
 889	}
 890
 891	/*
 892	 * copy the status so we know whether to remove the upcall from the
 893	 * list (for -EINPROGRESS, we just want to make sure the xid is
 894	 * valid, not remove the upcall from the list)
 895	 */
 896	if (get_user(status, &hdr->cm_status)) {
 897		dprintk("%s: error when copying status from userspace", __func__);
 898		return -EFAULT;
 899	}
 900
 901	/* walk the list and find corresponding xid */
 902	cup = NULL;
 903	spin_lock(&cn->cn_lock);
 904	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
 905		if (get_unaligned(&tmp->cu_u.cu_hdr.cm_xid) == xid) {
 906			cup = tmp;
 907			if (status != -EINPROGRESS)
 908				list_del_init(&cup->cu_list);
 909			break;
 910		}
 911	}
 912	spin_unlock(&cn->cn_lock);
 913
 914	/* couldn't find upcall? */
 915	if (!cup) {
 916		dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid);
 917		return -EINVAL;
 918	}
 919
 920	if (status == -EINPROGRESS)
 921		return __cld_pipe_inprogress_downcall(cmsg, nn);
 922
 923	if (copy_from_user(&cup->cu_u.cu_msg_v2, src, mlen) != 0)
 924		return -EFAULT;
 925
 926	complete(&cup->cu_done);
 927	return mlen;
 928}
 929
 930static void
 931cld_pipe_destroy_msg(struct rpc_pipe_msg *msg)
 932{
 933	struct cld_msg *cmsg = msg->data;
 934	struct cld_upcall *cup = container_of(cmsg, struct cld_upcall,
 935						 cu_u.cu_msg);
 936
 937	/* errno >= 0 means we got a downcall */
 938	if (msg->errno >= 0)
 939		return;
 940
 941	complete(&cup->cu_done);
 942}
 943
 944static const struct rpc_pipe_ops cld_upcall_ops = {
 945	.upcall		= rpc_pipe_generic_upcall,
 946	.downcall	= cld_pipe_downcall,
 947	.destroy_msg	= cld_pipe_destroy_msg,
 948};
 949
 950static struct dentry *
 951nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe)
 952{
 953	struct dentry *dir, *dentry;
 954
 955	dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR);
 956	if (dir == NULL)
 957		return ERR_PTR(-ENOENT);
 958	dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe);
 959	dput(dir);
 960	return dentry;
 961}
 962
 963static void
 964nfsd4_cld_unregister_sb(struct rpc_pipe *pipe)
 965{
 966	if (pipe->dentry)
 967		rpc_unlink(pipe->dentry);
 968}
 969
 970static struct dentry *
 971nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe)
 972{
 973	struct super_block *sb;
 974	struct dentry *dentry;
 975
 976	sb = rpc_get_sb_net(net);
 977	if (!sb)
 978		return NULL;
 979	dentry = nfsd4_cld_register_sb(sb, pipe);
 980	rpc_put_sb_net(net);
 981	return dentry;
 982}
 983
 984static void
 985nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe)
 986{
 987	struct super_block *sb;
 988
 989	sb = rpc_get_sb_net(net);
 990	if (sb) {
 991		nfsd4_cld_unregister_sb(pipe);
 992		rpc_put_sb_net(net);
 993	}
 994}
 995
 996/* Initialize rpc_pipefs pipe for communication with client tracking daemon */
 997static int
 998__nfsd4_init_cld_pipe(struct net *net)
 999{
1000	int ret;
1001	struct dentry *dentry;
1002	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1003	struct cld_net *cn;
1004
1005	if (nn->cld_net)
1006		return 0;
1007
1008	cn = kzalloc(sizeof(*cn), GFP_KERNEL);
1009	if (!cn) {
1010		ret = -ENOMEM;
1011		goto err;
1012	}
1013
1014	cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
1015	if (IS_ERR(cn->cn_pipe)) {
1016		ret = PTR_ERR(cn->cn_pipe);
1017		goto err;
1018	}
1019	spin_lock_init(&cn->cn_lock);
1020	INIT_LIST_HEAD(&cn->cn_list);
1021
1022	dentry = nfsd4_cld_register_net(net, cn->cn_pipe);
1023	if (IS_ERR(dentry)) {
1024		ret = PTR_ERR(dentry);
1025		goto err_destroy_data;
1026	}
1027
1028	cn->cn_pipe->dentry = dentry;
1029#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
1030	cn->cn_has_legacy = false;
1031#endif
1032	nn->cld_net = cn;
1033	return 0;
1034
1035err_destroy_data:
1036	rpc_destroy_pipe_data(cn->cn_pipe);
1037err:
1038	kfree(cn);
1039	printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n",
1040			ret);
1041	return ret;
1042}
1043
1044static int
1045nfsd4_init_cld_pipe(struct net *net)
1046{
1047	int status;
1048
1049	status = __nfsd4_init_cld_pipe(net);
1050	if (!status)
1051		pr_info("NFSD: Using old nfsdcld client tracking operations.\n");
1052	return status;
1053}
1054
1055static void
1056nfsd4_remove_cld_pipe(struct net *net)
1057{
1058	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1059	struct cld_net *cn = nn->cld_net;
1060
1061	nfsd4_cld_unregister_net(net, cn->cn_pipe);
1062	rpc_destroy_pipe_data(cn->cn_pipe);
1063	if (cn->cn_tfm)
1064		crypto_free_shash(cn->cn_tfm);
1065	kfree(nn->cld_net);
1066	nn->cld_net = NULL;
1067}
1068
1069static struct cld_upcall *
1070alloc_cld_upcall(struct nfsd_net *nn)
1071{
1072	struct cld_upcall *new, *tmp;
1073	struct cld_net *cn = nn->cld_net;
1074
1075	new = kzalloc(sizeof(*new), GFP_KERNEL);
1076	if (!new)
1077		return new;
1078
1079	/* FIXME: hard cap on number in flight? */
1080restart_search:
1081	spin_lock(&cn->cn_lock);
1082	list_for_each_entry(tmp, &cn->cn_list, cu_list) {
1083		if (tmp->cu_u.cu_msg.cm_xid == cn->cn_xid) {
1084			cn->cn_xid++;
1085			spin_unlock(&cn->cn_lock);
1086			goto restart_search;
1087		}
1088	}
1089	init_completion(&new->cu_done);
1090	new->cu_u.cu_msg.cm_vers = nn->client_tracking_ops->version;
1091	put_unaligned(cn->cn_xid++, &new->cu_u.cu_msg.cm_xid);
1092	new->cu_net = cn;
1093	list_add(&new->cu_list, &cn->cn_list);
1094	spin_unlock(&cn->cn_lock);
1095
1096	dprintk("%s: allocated xid %u\n", __func__, new->cu_u.cu_msg.cm_xid);
1097
1098	return new;
1099}
1100
1101static void
1102free_cld_upcall(struct cld_upcall *victim)
1103{
1104	struct cld_net *cn = victim->cu_net;
1105
1106	spin_lock(&cn->cn_lock);
1107	list_del(&victim->cu_list);
1108	spin_unlock(&cn->cn_lock);
1109	kfree(victim);
1110}
1111
1112/* Ask daemon to create a new record */
1113static void
1114nfsd4_cld_create(struct nfs4_client *clp)
1115{
1116	int ret;
1117	struct cld_upcall *cup;
1118	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
1119	struct cld_net *cn = nn->cld_net;
1120
1121	/* Don't upcall if it's already stored */
1122	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1123		return;
1124
1125	cup = alloc_cld_upcall(nn);
1126	if (!cup) {
1127		ret = -ENOMEM;
1128		goto out_err;
1129	}
1130
1131	cup->cu_u.cu_msg.cm_cmd = Cld_Create;
1132	cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1133	memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1134			clp->cl_name.len);
1135
1136	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1137	if (!ret) {
1138		ret = cup->cu_u.cu_msg.cm_status;
1139		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1140	}
1141
1142	free_cld_upcall(cup);
1143out_err:
1144	if (ret)
1145		printk(KERN_ERR "NFSD: Unable to create client "
1146				"record on stable storage: %d\n", ret);
1147}
1148
1149/* Ask daemon to create a new record */
1150static void
1151nfsd4_cld_create_v2(struct nfs4_client *clp)
1152{
1153	int ret;
1154	struct cld_upcall *cup;
1155	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1156	struct cld_net *cn = nn->cld_net;
1157	struct cld_msg_v2 *cmsg;
1158	struct crypto_shash *tfm = cn->cn_tfm;
1159	struct xdr_netobj cksum;
1160	char *principal = NULL;
1161
1162	/* Don't upcall if it's already stored */
1163	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1164		return;
1165
1166	cup = alloc_cld_upcall(nn);
1167	if (!cup) {
1168		ret = -ENOMEM;
1169		goto out_err;
1170	}
1171
1172	cmsg = &cup->cu_u.cu_msg_v2;
1173	cmsg->cm_cmd = Cld_Create;
1174	cmsg->cm_u.cm_clntinfo.cc_name.cn_len = clp->cl_name.len;
1175	memcpy(cmsg->cm_u.cm_clntinfo.cc_name.cn_id, clp->cl_name.data,
1176			clp->cl_name.len);
1177	if (clp->cl_cred.cr_raw_principal)
1178		principal = clp->cl_cred.cr_raw_principal;
1179	else if (clp->cl_cred.cr_principal)
1180		principal = clp->cl_cred.cr_principal;
1181	if (principal) {
1182		cksum.len = crypto_shash_digestsize(tfm);
1183		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
1184		if (cksum.data == NULL) {
1185			ret = -ENOMEM;
1186			goto out;
1187		}
1188		ret = crypto_shash_tfm_digest(tfm, principal, strlen(principal),
1189					      cksum.data);
1190		if (ret) {
1191			kfree(cksum.data);
1192			goto out;
1193		}
1194		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = cksum.len;
1195		memcpy(cmsg->cm_u.cm_clntinfo.cc_princhash.cp_data,
1196		       cksum.data, cksum.len);
1197		kfree(cksum.data);
1198	} else
1199		cmsg->cm_u.cm_clntinfo.cc_princhash.cp_len = 0;
1200
1201	ret = cld_pipe_upcall(cn->cn_pipe, cmsg, nn);
1202	if (!ret) {
1203		ret = cmsg->cm_status;
1204		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1205	}
1206
1207out:
1208	free_cld_upcall(cup);
1209out_err:
1210	if (ret)
1211		pr_err("NFSD: Unable to create client record on stable storage: %d\n",
1212				ret);
1213}
1214
1215/* Ask daemon to create a new record */
1216static void
1217nfsd4_cld_remove(struct nfs4_client *clp)
1218{
1219	int ret;
1220	struct cld_upcall *cup;
1221	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
1222	struct cld_net *cn = nn->cld_net;
1223
1224	/* Don't upcall if it's already removed */
1225	if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1226		return;
1227
1228	cup = alloc_cld_upcall(nn);
1229	if (!cup) {
1230		ret = -ENOMEM;
1231		goto out_err;
1232	}
1233
1234	cup->cu_u.cu_msg.cm_cmd = Cld_Remove;
1235	cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1236	memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1237			clp->cl_name.len);
1238
1239	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1240	if (!ret) {
1241		ret = cup->cu_u.cu_msg.cm_status;
1242		clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1243	}
1244
1245	free_cld_upcall(cup);
1246out_err:
1247	if (ret)
1248		printk(KERN_ERR "NFSD: Unable to remove client "
1249				"record from stable storage: %d\n", ret);
1250}
1251
1252/*
1253 * For older nfsdcld's that do not allow us to "slurp" the clients
1254 * from the tracking database during startup.
1255 *
1256 * Check for presence of a record, and update its timestamp
1257 */
1258static int
1259nfsd4_cld_check_v0(struct nfs4_client *clp)
1260{
1261	int ret;
1262	struct cld_upcall *cup;
1263	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
 
1264	struct cld_net *cn = nn->cld_net;
1265
1266	/* Don't upcall if one was already stored during this grace pd */
1267	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1268		return 0;
1269
1270	cup = alloc_cld_upcall(nn);
1271	if (!cup) {
1272		printk(KERN_ERR "NFSD: Unable to check client record on "
1273				"stable storage: %d\n", -ENOMEM);
1274		return -ENOMEM;
1275	}
1276
1277	cup->cu_u.cu_msg.cm_cmd = Cld_Check;
1278	cup->cu_u.cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len;
1279	memcpy(cup->cu_u.cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data,
1280			clp->cl_name.len);
1281
1282	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1283	if (!ret) {
1284		ret = cup->cu_u.cu_msg.cm_status;
1285		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1286	}
1287
1288	free_cld_upcall(cup);
1289	return ret;
1290}
1291
1292/*
1293 * For newer nfsdcld's that allow us to "slurp" the clients
1294 * from the tracking database during startup.
1295 *
1296 * Check for presence of a record in the reclaim_str_hashtbl
1297 */
1298static int
1299nfsd4_cld_check(struct nfs4_client *clp)
1300{
1301	struct nfs4_client_reclaim *crp;
1302	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1303
1304	/* did we already find that this client is stable? */
1305	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1306		return 0;
1307
1308	/* look for it in the reclaim hashtable otherwise */
1309	crp = nfsd4_find_reclaim_client(clp->cl_name, nn);
1310	if (crp)
1311		goto found;
1312
1313#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
1314	if (nn->cld_net->cn_has_legacy) {
1315		int status;
1316		char dname[HEXDIR_LEN];
1317		struct xdr_netobj name;
1318
1319		status = nfs4_make_rec_clidname(dname, &clp->cl_name);
1320		if (status)
1321			return -ENOENT;
1322
1323		name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
1324		if (!name.data) {
1325			dprintk("%s: failed to allocate memory for name.data!\n",
1326				__func__);
1327			return -ENOENT;
1328		}
1329		name.len = HEXDIR_LEN;
1330		crp = nfsd4_find_reclaim_client(name, nn);
1331		kfree(name.data);
1332		if (crp)
1333			goto found;
1334
1335	}
1336#endif
1337	return -ENOENT;
1338found:
1339	crp->cr_clp = clp;
1340	return 0;
1341}
1342
1343static int
1344nfsd4_cld_check_v2(struct nfs4_client *clp)
1345{
1346	struct nfs4_client_reclaim *crp;
1347	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1348	struct cld_net *cn = nn->cld_net;
1349	int status;
1350	struct crypto_shash *tfm = cn->cn_tfm;
1351	struct xdr_netobj cksum;
1352	char *principal = NULL;
1353
1354	/* did we already find that this client is stable? */
1355	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1356		return 0;
1357
1358	/* look for it in the reclaim hashtable otherwise */
1359	crp = nfsd4_find_reclaim_client(clp->cl_name, nn);
1360	if (crp)
1361		goto found;
1362
1363#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
1364	if (cn->cn_has_legacy) {
1365		struct xdr_netobj name;
1366		char dname[HEXDIR_LEN];
1367
1368		status = nfs4_make_rec_clidname(dname, &clp->cl_name);
1369		if (status)
1370			return -ENOENT;
1371
1372		name.data = kmemdup(dname, HEXDIR_LEN, GFP_KERNEL);
1373		if (!name.data) {
1374			dprintk("%s: failed to allocate memory for name.data\n",
1375					__func__);
1376			return -ENOENT;
1377		}
1378		name.len = HEXDIR_LEN;
1379		crp = nfsd4_find_reclaim_client(name, nn);
1380		kfree(name.data);
1381		if (crp)
1382			goto found;
1383
1384	}
1385#endif
1386	return -ENOENT;
1387found:
1388	if (crp->cr_princhash.len) {
1389		if (clp->cl_cred.cr_raw_principal)
1390			principal = clp->cl_cred.cr_raw_principal;
1391		else if (clp->cl_cred.cr_principal)
1392			principal = clp->cl_cred.cr_principal;
1393		if (principal == NULL)
1394			return -ENOENT;
1395		cksum.len = crypto_shash_digestsize(tfm);
1396		cksum.data = kmalloc(cksum.len, GFP_KERNEL);
1397		if (cksum.data == NULL)
1398			return -ENOENT;
1399		status = crypto_shash_tfm_digest(tfm, principal,
1400						 strlen(principal), cksum.data);
1401		if (status) {
1402			kfree(cksum.data);
1403			return -ENOENT;
1404		}
1405		if (memcmp(crp->cr_princhash.data, cksum.data,
1406				crp->cr_princhash.len)) {
1407			kfree(cksum.data);
1408			return -ENOENT;
1409		}
1410		kfree(cksum.data);
1411	}
1412	crp->cr_clp = clp;
1413	return 0;
1414}
1415
1416static int
1417nfsd4_cld_grace_start(struct nfsd_net *nn)
1418{
1419	int ret;
1420	struct cld_upcall *cup;
1421	struct cld_net *cn = nn->cld_net;
1422
1423	cup = alloc_cld_upcall(nn);
1424	if (!cup) {
1425		ret = -ENOMEM;
1426		goto out_err;
1427	}
1428
1429	cup->cu_u.cu_msg.cm_cmd = Cld_GraceStart;
1430	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1431	if (!ret)
1432		ret = cup->cu_u.cu_msg.cm_status;
1433
1434	free_cld_upcall(cup);
1435out_err:
1436	if (ret)
1437		dprintk("%s: Unable to get clients from userspace: %d\n",
1438			__func__, ret);
1439	return ret;
1440}
1441
1442/* For older nfsdcld's that need cm_gracetime */
1443static void
1444nfsd4_cld_grace_done_v0(struct nfsd_net *nn)
1445{
1446	int ret;
1447	struct cld_upcall *cup;
1448	struct cld_net *cn = nn->cld_net;
1449
1450	cup = alloc_cld_upcall(nn);
1451	if (!cup) {
1452		ret = -ENOMEM;
1453		goto out_err;
1454	}
1455
1456	cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone;
1457	cup->cu_u.cu_msg.cm_u.cm_gracetime = nn->boot_time;
1458	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1459	if (!ret)
1460		ret = cup->cu_u.cu_msg.cm_status;
1461
1462	free_cld_upcall(cup);
1463out_err:
1464	if (ret)
1465		printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
1466}
1467
1468/*
1469 * For newer nfsdcld's that do not need cm_gracetime.  We also need to call
1470 * nfs4_release_reclaim() to clear out the reclaim_str_hashtbl.
1471 */
1472static void
1473nfsd4_cld_grace_done(struct nfsd_net *nn)
1474{
1475	int ret;
1476	struct cld_upcall *cup;
 
1477	struct cld_net *cn = nn->cld_net;
1478
1479	cup = alloc_cld_upcall(nn);
1480	if (!cup) {
1481		ret = -ENOMEM;
1482		goto out_err;
1483	}
1484
1485	cup->cu_u.cu_msg.cm_cmd = Cld_GraceDone;
1486	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
 
1487	if (!ret)
1488		ret = cup->cu_u.cu_msg.cm_status;
1489
1490	free_cld_upcall(cup);
1491out_err:
1492	nfs4_release_reclaim(nn);
1493	if (ret)
1494		printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret);
1495}
1496
1497static int
1498nfs4_cld_state_init(struct net *net)
1499{
1500	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1501	int i;
1502
1503	nn->reclaim_str_hashtbl = kmalloc_array(CLIENT_HASH_SIZE,
1504						sizeof(struct list_head),
1505						GFP_KERNEL);
1506	if (!nn->reclaim_str_hashtbl)
1507		return -ENOMEM;
1508
1509	for (i = 0; i < CLIENT_HASH_SIZE; i++)
1510		INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]);
1511	nn->reclaim_str_hashtbl_size = 0;
1512	nn->track_reclaim_completes = true;
1513	atomic_set(&nn->nr_reclaim_complete, 0);
1514
1515	return 0;
1516}
1517
1518static void
1519nfs4_cld_state_shutdown(struct net *net)
1520{
1521	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1522
1523	nn->track_reclaim_completes = false;
1524	kfree(nn->reclaim_str_hashtbl);
1525}
1526
1527static bool
1528cld_running(struct nfsd_net *nn)
1529{
1530	struct cld_net *cn = nn->cld_net;
1531	struct rpc_pipe *pipe = cn->cn_pipe;
1532
1533	return pipe->nreaders || pipe->nwriters;
1534}
1535
1536static int
1537nfsd4_cld_get_version(struct nfsd_net *nn)
1538{
1539	int ret = 0;
1540	struct cld_upcall *cup;
1541	struct cld_net *cn = nn->cld_net;
1542	uint8_t version;
1543
1544	cup = alloc_cld_upcall(nn);
1545	if (!cup) {
1546		ret = -ENOMEM;
1547		goto out_err;
1548	}
1549	cup->cu_u.cu_msg.cm_cmd = Cld_GetVersion;
1550	ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_u.cu_msg, nn);
1551	if (!ret) {
1552		ret = cup->cu_u.cu_msg.cm_status;
1553		if (ret)
1554			goto out_free;
1555		version = cup->cu_u.cu_msg.cm_u.cm_version;
1556		dprintk("%s: userspace returned version %u\n",
1557				__func__, version);
1558		if (version < 1)
1559			version = 1;
1560		else if (version > CLD_UPCALL_VERSION)
1561			version = CLD_UPCALL_VERSION;
1562
1563		switch (version) {
1564		case 1:
1565			nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
1566			break;
1567		case 2:
1568			nn->client_tracking_ops = &nfsd4_cld_tracking_ops_v2;
1569			break;
1570		default:
1571			break;
1572		}
1573	}
1574out_free:
1575	free_cld_upcall(cup);
1576out_err:
1577	if (ret)
1578		dprintk("%s: Unable to get version from userspace: %d\n",
1579			__func__, ret);
1580	return ret;
1581}
1582
1583static int
1584nfsd4_cld_tracking_init(struct net *net)
1585{
1586	int status;
1587	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1588	bool running;
1589	int retries = 10;
1590	struct crypto_shash *tfm;
1591
1592	status = nfs4_cld_state_init(net);
1593	if (status)
1594		return status;
1595
1596	status = __nfsd4_init_cld_pipe(net);
1597	if (status)
1598		goto err_shutdown;
1599
1600	/*
1601	 * rpc pipe upcalls take 30 seconds to time out, so we don't want to
1602	 * queue an upcall unless we know that nfsdcld is running (because we
1603	 * want this to fail fast so that nfsd4_client_tracking_init() can try
1604	 * the next client tracking method).  nfsdcld should already be running
1605	 * before nfsd is started, so the wait here is for nfsdcld to open the
1606	 * pipefs file we just created.
1607	 */
1608	while (!(running = cld_running(nn)) && retries--)
1609		msleep(100);
1610
1611	if (!running) {
1612		status = -ETIMEDOUT;
1613		goto err_remove;
1614	}
1615	tfm = crypto_alloc_shash("sha256", 0, 0);
1616	if (IS_ERR(tfm)) {
1617		status = PTR_ERR(tfm);
1618		goto err_remove;
1619	}
1620	nn->cld_net->cn_tfm = tfm;
1621
1622	status = nfsd4_cld_get_version(nn);
1623	if (status == -EOPNOTSUPP)
1624		pr_warn("NFSD: nfsdcld GetVersion upcall failed. Please upgrade nfsdcld.\n");
1625
1626	status = nfsd4_cld_grace_start(nn);
1627	if (status) {
1628		if (status == -EOPNOTSUPP)
1629			pr_warn("NFSD: nfsdcld GraceStart upcall failed. Please upgrade nfsdcld.\n");
1630		nfs4_release_reclaim(nn);
1631		goto err_remove;
1632	} else
1633		pr_info("NFSD: Using nfsdcld client tracking operations.\n");
1634	return 0;
1635
1636err_remove:
1637	nfsd4_remove_cld_pipe(net);
1638err_shutdown:
1639	nfs4_cld_state_shutdown(net);
1640	return status;
1641}
1642
1643static void
1644nfsd4_cld_tracking_exit(struct net *net)
1645{
1646	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1647
1648	nfs4_release_reclaim(nn);
1649	nfsd4_remove_cld_pipe(net);
1650	nfs4_cld_state_shutdown(net);
1651}
1652
1653/* For older nfsdcld's */
1654static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v0 = {
1655	.init		= nfsd4_init_cld_pipe,
1656	.exit		= nfsd4_remove_cld_pipe,
1657	.create		= nfsd4_cld_create,
1658	.remove		= nfsd4_cld_remove,
1659	.check		= nfsd4_cld_check_v0,
1660	.grace_done	= nfsd4_cld_grace_done_v0,
1661	.version	= 1,
1662	.msglen		= sizeof(struct cld_msg),
1663};
1664
1665/* For newer nfsdcld's */
1666static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = {
1667	.init		= nfsd4_cld_tracking_init,
1668	.exit		= nfsd4_cld_tracking_exit,
1669	.create		= nfsd4_cld_create,
1670	.remove		= nfsd4_cld_remove,
1671	.check		= nfsd4_cld_check,
1672	.grace_done	= nfsd4_cld_grace_done,
1673	.version	= 1,
1674	.msglen		= sizeof(struct cld_msg),
1675};
1676
1677/* v2 create/check ops include the principal, if available */
1678static const struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops_v2 = {
1679	.init		= nfsd4_cld_tracking_init,
1680	.exit		= nfsd4_cld_tracking_exit,
1681	.create		= nfsd4_cld_create_v2,
1682	.remove		= nfsd4_cld_remove,
1683	.check		= nfsd4_cld_check_v2,
1684	.grace_done	= nfsd4_cld_grace_done,
1685	.version	= 2,
1686	.msglen		= sizeof(struct cld_msg_v2),
1687};
1688
1689#ifdef CONFIG_NFSD_LEGACY_CLIENT_TRACKING
1690/* upcall via usermodehelper */
1691static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack";
1692module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog),
1693			S_IRUGO|S_IWUSR);
1694MODULE_PARM_DESC(cltrack_prog, "Path to the nfsdcltrack upcall program");
1695
1696static bool cltrack_legacy_disable;
1697module_param(cltrack_legacy_disable, bool, S_IRUGO|S_IWUSR);
1698MODULE_PARM_DESC(cltrack_legacy_disable,
1699		"Disable legacy recoverydir conversion. Default: false");
1700
1701#define LEGACY_TOPDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_TOPDIR="
1702#define LEGACY_RECDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_RECDIR="
1703#define HAS_SESSION_ENV_PREFIX "NFSDCLTRACK_CLIENT_HAS_SESSION="
1704#define GRACE_START_ENV_PREFIX "NFSDCLTRACK_GRACE_START="
1705
1706static char *
1707nfsd4_cltrack_legacy_topdir(void)
1708{
1709	int copied;
1710	size_t len;
1711	char *result;
1712
1713	if (cltrack_legacy_disable)
1714		return NULL;
1715
1716	len = strlen(LEGACY_TOPDIR_ENV_PREFIX) +
1717		strlen(nfs4_recoverydir()) + 1;
1718
1719	result = kmalloc(len, GFP_KERNEL);
1720	if (!result)
1721		return result;
1722
1723	copied = snprintf(result, len, LEGACY_TOPDIR_ENV_PREFIX "%s",
1724				nfs4_recoverydir());
1725	if (copied >= len) {
1726		/* just return nothing if output was truncated */
1727		kfree(result);
1728		return NULL;
1729	}
1730
1731	return result;
1732}
1733
1734static char *
1735nfsd4_cltrack_legacy_recdir(const struct xdr_netobj *name)
1736{
1737	int copied;
1738	size_t len;
1739	char *result;
1740
1741	if (cltrack_legacy_disable)
1742		return NULL;
1743
1744	/* +1 is for '/' between "topdir" and "recdir" */
1745	len = strlen(LEGACY_RECDIR_ENV_PREFIX) +
1746		strlen(nfs4_recoverydir()) + 1 + HEXDIR_LEN;
1747
1748	result = kmalloc(len, GFP_KERNEL);
1749	if (!result)
1750		return result;
1751
1752	copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/",
1753				nfs4_recoverydir());
1754	if (copied > (len - HEXDIR_LEN)) {
1755		/* just return nothing if output will be truncated */
1756		kfree(result);
1757		return NULL;
1758	}
1759
1760	copied = nfs4_make_rec_clidname(result + copied, name);
1761	if (copied) {
1762		kfree(result);
1763		return NULL;
1764	}
1765
1766	return result;
1767}
1768
1769static char *
1770nfsd4_cltrack_client_has_session(struct nfs4_client *clp)
1771{
1772	int copied;
1773	size_t len;
1774	char *result;
1775
1776	/* prefix + Y/N character + terminating NULL */
1777	len = strlen(HAS_SESSION_ENV_PREFIX) + 1 + 1;
1778
1779	result = kmalloc(len, GFP_KERNEL);
1780	if (!result)
1781		return result;
1782
1783	copied = snprintf(result, len, HAS_SESSION_ENV_PREFIX "%c",
1784				clp->cl_minorversion ? 'Y' : 'N');
1785	if (copied >= len) {
1786		/* just return nothing if output was truncated */
1787		kfree(result);
1788		return NULL;
1789	}
1790
1791	return result;
1792}
1793
1794static char *
1795nfsd4_cltrack_grace_start(time64_t grace_start)
1796{
1797	int copied;
1798	size_t len;
1799	char *result;
1800
1801	/* prefix + max width of int64_t string + terminating NULL */
1802	len = strlen(GRACE_START_ENV_PREFIX) + 22 + 1;
1803
1804	result = kmalloc(len, GFP_KERNEL);
1805	if (!result)
1806		return result;
1807
1808	copied = snprintf(result, len, GRACE_START_ENV_PREFIX "%lld",
1809				grace_start);
1810	if (copied >= len) {
1811		/* just return nothing if output was truncated */
1812		kfree(result);
1813		return NULL;
1814	}
1815
1816	return result;
1817}
1818
1819static int
1820nfsd4_umh_cltrack_upcall(char *cmd, char *arg, char *env0, char *env1)
1821{
1822	char *envp[3];
1823	char *argv[4];
1824	int ret;
1825
1826	if (unlikely(!cltrack_prog[0])) {
1827		dprintk("%s: cltrack_prog is disabled\n", __func__);
1828		return -EACCES;
1829	}
1830
1831	dprintk("%s: cmd: %s\n", __func__, cmd);
1832	dprintk("%s: arg: %s\n", __func__, arg ? arg : "(null)");
1833	dprintk("%s: env0: %s\n", __func__, env0 ? env0 : "(null)");
1834	dprintk("%s: env1: %s\n", __func__, env1 ? env1 : "(null)");
1835
1836	envp[0] = env0;
1837	envp[1] = env1;
1838	envp[2] = NULL;
1839
1840	argv[0] = (char *)cltrack_prog;
1841	argv[1] = cmd;
1842	argv[2] = arg;
1843	argv[3] = NULL;
1844
1845	ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
1846	/*
1847	 * Disable the upcall mechanism if we're getting an ENOENT or EACCES
1848	 * error. The admin can re-enable it on the fly by using sysfs
1849	 * once the problem has been fixed.
1850	 */
1851	if (ret == -ENOENT || ret == -EACCES) {
1852		dprintk("NFSD: %s was not found or isn't executable (%d). "
1853			"Setting cltrack_prog to blank string!",
1854			cltrack_prog, ret);
1855		cltrack_prog[0] = '\0';
1856	}
1857	dprintk("%s: %s return value: %d\n", __func__, cltrack_prog, ret);
1858
1859	return ret;
1860}
1861
1862static char *
1863bin_to_hex_dup(const unsigned char *src, int srclen)
1864{
1865	char *buf;
1866
1867	/* +1 for terminating NULL */
1868	buf = kzalloc((srclen * 2) + 1, GFP_KERNEL);
1869	if (!buf)
1870		return buf;
1871
1872	bin2hex(buf, src, srclen);
1873	return buf;
1874}
1875
1876static int
1877nfsd4_umh_cltrack_init(struct net *net)
1878{
1879	int ret;
1880	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
1881	char *grace_start = nfsd4_cltrack_grace_start(nn->boot_time);
1882
1883	/* XXX: The usermode helper s not working in container yet. */
1884	if (net != &init_net) {
1885		pr_warn("NFSD: attempt to initialize umh client tracking in a container ignored.\n");
1886		kfree(grace_start);
1887		return -EINVAL;
1888	}
1889
1890	ret = nfsd4_umh_cltrack_upcall("init", NULL, grace_start, NULL);
1891	kfree(grace_start);
1892	if (!ret)
1893		pr_info("NFSD: Using UMH upcall client tracking operations.\n");
1894	return ret;
1895}
1896
1897static void
1898nfsd4_cltrack_upcall_lock(struct nfs4_client *clp)
1899{
1900	wait_on_bit_lock(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK,
1901			 TASK_UNINTERRUPTIBLE);
1902}
1903
1904static void
1905nfsd4_cltrack_upcall_unlock(struct nfs4_client *clp)
1906{
1907	clear_and_wake_up_bit(NFSD4_CLIENT_UPCALL_LOCK, &clp->cl_flags);
1908}
1909
1910static void
1911nfsd4_umh_cltrack_create(struct nfs4_client *clp)
1912{
1913	char *hexid, *has_session, *grace_start;
1914	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
1915
1916	/*
1917	 * With v4.0 clients, there's little difference in outcome between a
1918	 * create and check operation, and we can end up calling into this
1919	 * function multiple times per client (once for each openowner). So,
1920	 * for v4.0 clients skip upcalling once the client has been recorded
1921	 * on stable storage.
1922	 *
1923	 * For v4.1+ clients, the outcome of the two operations is different,
1924	 * so we must ensure that we upcall for the create operation. v4.1+
1925	 * clients call this on RECLAIM_COMPLETE though, so we should only end
1926	 * up doing a single create upcall per client.
1927	 */
1928	if (clp->cl_minorversion == 0 &&
1929	    test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1930		return;
1931
1932	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1933	if (!hexid) {
1934		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1935		return;
1936	}
1937
1938	has_session = nfsd4_cltrack_client_has_session(clp);
1939	grace_start = nfsd4_cltrack_grace_start(nn->boot_time);
1940
1941	nfsd4_cltrack_upcall_lock(clp);
1942	if (!nfsd4_umh_cltrack_upcall("create", hexid, has_session, grace_start))
1943		set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1944	nfsd4_cltrack_upcall_unlock(clp);
1945
1946	kfree(has_session);
1947	kfree(grace_start);
1948	kfree(hexid);
1949}
1950
1951static void
1952nfsd4_umh_cltrack_remove(struct nfs4_client *clp)
1953{
1954	char *hexid;
1955
1956	if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1957		return;
1958
1959	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1960	if (!hexid) {
1961		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1962		return;
1963	}
1964
1965	nfsd4_cltrack_upcall_lock(clp);
1966	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags) &&
1967	    nfsd4_umh_cltrack_upcall("remove", hexid, NULL, NULL) == 0)
1968		clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1969	nfsd4_cltrack_upcall_unlock(clp);
1970
1971	kfree(hexid);
1972}
1973
1974static int
1975nfsd4_umh_cltrack_check(struct nfs4_client *clp)
1976{
1977	int ret;
1978	char *hexid, *has_session, *legacy;
1979
1980	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
1981		return 0;
1982
1983	hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len);
1984	if (!hexid) {
1985		dprintk("%s: can't allocate memory for upcall!\n", __func__);
1986		return -ENOMEM;
1987	}
1988
1989	has_session = nfsd4_cltrack_client_has_session(clp);
1990	legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name);
1991
1992	nfsd4_cltrack_upcall_lock(clp);
1993	if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) {
1994		ret = 0;
1995	} else {
1996		ret = nfsd4_umh_cltrack_upcall("check", hexid, has_session, legacy);
1997		if (ret == 0)
1998			set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
1999	}
2000	nfsd4_cltrack_upcall_unlock(clp);
2001	kfree(has_session);
2002	kfree(legacy);
2003	kfree(hexid);
2004
2005	return ret;
2006}
2007
2008static void
2009nfsd4_umh_cltrack_grace_done(struct nfsd_net *nn)
2010{
2011	char *legacy;
2012	char timestr[22]; /* FIXME: better way to determine max size? */
2013
2014	sprintf(timestr, "%lld", nn->boot_time);
2015	legacy = nfsd4_cltrack_legacy_topdir();
2016	nfsd4_umh_cltrack_upcall("gracedone", timestr, legacy, NULL);
2017	kfree(legacy);
2018}
2019
2020static const struct nfsd4_client_tracking_ops nfsd4_umh_tracking_ops = {
2021	.init		= nfsd4_umh_cltrack_init,
2022	.exit		= NULL,
2023	.create		= nfsd4_umh_cltrack_create,
2024	.remove		= nfsd4_umh_cltrack_remove,
2025	.check		= nfsd4_umh_cltrack_check,
2026	.grace_done	= nfsd4_umh_cltrack_grace_done,
2027	.version	= 1,
2028	.msglen		= 0,
2029};
2030
2031static inline int check_for_legacy_methods(int status, struct net *net)
2032{
2033	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2034	struct path path;
2035
2036	/*
2037	 * Next, try the UMH upcall.
2038	 */
2039	nn->client_tracking_ops = &nfsd4_umh_tracking_ops;
2040	status = nn->client_tracking_ops->init(net);
2041	if (!status)
2042		return status;
2043
2044	/*
2045	 * Finally, See if the recoverydir exists and is a directory.
2046	 * If it is, then use the legacy ops.
2047	 */
2048	nn->client_tracking_ops = &nfsd4_legacy_tracking_ops;
2049	status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path);
2050	if (!status) {
2051		status = !d_is_dir(path.dentry);
2052		path_put(&path);
2053		if (status)
2054			return -ENOTDIR;
2055		status = nn->client_tracking_ops->init(net);
2056	}
2057	return status;
2058}
2059#else
2060static inline int check_for_legacy_methods(int status, struct net *net)
2061{
2062	return status;
2063}
2064#endif /* CONFIG_LEGACY_NFSD_CLIENT_TRACKING */
2065
2066int
2067nfsd4_client_tracking_init(struct net *net)
2068{
2069	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2070	int status;
 
2071
2072	/* just run the init if it the method is already decided */
2073	if (nn->client_tracking_ops)
2074		goto do_init;
2075
2076	/* First, try to use nfsdcld */
2077	nn->client_tracking_ops = &nfsd4_cld_tracking_ops;
2078	status = nn->client_tracking_ops->init(net);
2079	if (!status)
2080		return status;
2081	if (status != -ETIMEDOUT) {
2082		nn->client_tracking_ops = &nfsd4_cld_tracking_ops_v0;
2083		status = nn->client_tracking_ops->init(net);
2084		if (!status)
2085			return status;
2086	}
2087
2088	status = check_for_legacy_methods(status, net);
2089	if (status)
2090		goto out;
2091do_init:
2092	status = nn->client_tracking_ops->init(net);
2093out:
2094	if (status) {
2095		pr_warn("NFSD: Unable to initialize client recovery tracking! (%d)\n", status);
2096		pr_warn("NFSD: Is nfsdcld running? If not, enable CONFIG_NFSD_LEGACY_CLIENT_TRACKING.\n");
2097		nn->client_tracking_ops = NULL;
2098	}
2099	return status;
2100}
2101
2102void
2103nfsd4_client_tracking_exit(struct net *net)
2104{
2105	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2106
2107	if (nn->client_tracking_ops) {
2108		if (nn->client_tracking_ops->exit)
2109			nn->client_tracking_ops->exit(net);
2110		nn->client_tracking_ops = NULL;
2111	}
2112}
2113
2114void
2115nfsd4_client_record_create(struct nfs4_client *clp)
2116{
2117	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2118
2119	if (nn->client_tracking_ops)
2120		nn->client_tracking_ops->create(clp);
2121}
2122
2123void
2124nfsd4_client_record_remove(struct nfs4_client *clp)
2125{
2126	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2127
2128	if (nn->client_tracking_ops)
2129		nn->client_tracking_ops->remove(clp);
2130}
2131
2132int
2133nfsd4_client_record_check(struct nfs4_client *clp)
2134{
2135	struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id);
2136
2137	if (nn->client_tracking_ops)
2138		return nn->client_tracking_ops->check(clp);
2139
2140	return -EOPNOTSUPP;
2141}
2142
2143void
2144nfsd4_record_grace_done(struct nfsd_net *nn)
2145{
2146	if (nn->client_tracking_ops)
2147		nn->client_tracking_ops->grace_done(nn);
2148}
2149
2150static int
2151rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr)
2152{
2153	struct super_block *sb = ptr;
2154	struct net *net = sb->s_fs_info;
2155	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
2156	struct cld_net *cn = nn->cld_net;
2157	struct dentry *dentry;
2158	int ret = 0;
2159
2160	if (!try_module_get(THIS_MODULE))
2161		return 0;
2162
2163	if (!cn) {
2164		module_put(THIS_MODULE);
2165		return 0;
2166	}
2167
2168	switch (event) {
2169	case RPC_PIPEFS_MOUNT:
2170		dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe);
2171		if (IS_ERR(dentry)) {
2172			ret = PTR_ERR(dentry);
2173			break;
2174		}
2175		cn->cn_pipe->dentry = dentry;
2176		break;
2177	case RPC_PIPEFS_UMOUNT:
2178		if (cn->cn_pipe->dentry)
2179			nfsd4_cld_unregister_sb(cn->cn_pipe);
2180		break;
2181	default:
2182		ret = -ENOTSUPP;
2183		break;
2184	}
2185	module_put(THIS_MODULE);
2186	return ret;
2187}
2188
2189static struct notifier_block nfsd4_cld_block = {
2190	.notifier_call = rpc_pipefs_event,
2191};
2192
2193int
2194register_cld_notifier(void)
2195{
2196	WARN_ON(!nfsd_net_id);
2197	return rpc_pipefs_notifier_register(&nfsd4_cld_block);
2198}
2199
2200void
2201unregister_cld_notifier(void)
2202{
2203	rpc_pipefs_notifier_unregister(&nfsd4_cld_block);
2204}