rpc_pipe.c 18.8 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5
/*
 * net/sunrpc/rpc_pipe.c
 *
 * Userland/kernel interface for rpcauth_gss.
 * Code shamelessly plagiarized from fs/nfsd/nfsctl.c
6
 * and fs/sysfs/inode.c
L
Linus Torvalds 已提交
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
 *
 * Copyright (c) 2002, Trond Myklebust <trond.myklebust@fys.uio.no>
 *
 */
#include <linux/config.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/pagemap.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/dnotify.h>
#include <linux/kernel.h>

#include <asm/ioctls.h>
#include <linux/fs.h>
#include <linux/poll.h>
#include <linux/wait.h>
#include <linux/seq_file.h>

#include <linux/sunrpc/clnt.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/rpc_pipe_fs.h>

31
static struct vfsmount *rpc_mount __read_mostly;
L
Linus Torvalds 已提交
32 33 34 35 36
static int rpc_mount_count;

static struct file_system_type rpc_pipe_fs_type;


37
static kmem_cache_t *rpc_inode_cachep __read_mostly;
L
Linus Torvalds 已提交
38 39 40

#define RPC_UPCALL_TIMEOUT (30*HZ)

41 42
static void rpc_purge_list(struct rpc_inode *rpci, struct list_head *head,
		void (*destroy_msg)(struct rpc_pipe_msg *), int err)
L
Linus Torvalds 已提交
43 44 45
{
	struct rpc_pipe_msg *msg;

46 47 48
	if (list_empty(head))
		return;
	do {
49
		msg = list_entry(head->next, struct rpc_pipe_msg, list);
50
		list_del(&msg->list);
L
Linus Torvalds 已提交
51
		msg->errno = err;
52
		destroy_msg(msg);
53
	} while (!list_empty(head));
L
Linus Torvalds 已提交
54 55 56 57 58 59
	wake_up(&rpci->waitq);
}

static void
rpc_timeout_upcall_queue(void *data)
{
60
	LIST_HEAD(free_list);
L
Linus Torvalds 已提交
61 62
	struct rpc_inode *rpci = (struct rpc_inode *)data;
	struct inode *inode = &rpci->vfs_inode;
63
	void (*destroy_msg)(struct rpc_pipe_msg *);
L
Linus Torvalds 已提交
64

65 66 67 68 69 70 71 72 73 74 75 76
	spin_lock(&inode->i_lock);
	if (rpci->ops == NULL) {
		spin_unlock(&inode->i_lock);
		return;
	}
	destroy_msg = rpci->ops->destroy_msg;
	if (rpci->nreaders == 0) {
		list_splice_init(&rpci->pipe, &free_list);
		rpci->pipelen = 0;
	}
	spin_unlock(&inode->i_lock);
	rpc_purge_list(rpci, &free_list, destroy_msg, -ETIMEDOUT);
L
Linus Torvalds 已提交
77 78 79 80 81 82
}

int
rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg)
{
	struct rpc_inode *rpci = RPC_I(inode);
83
	int res = -EPIPE;
L
Linus Torvalds 已提交
84

85
	spin_lock(&inode->i_lock);
86 87
	if (rpci->ops == NULL)
		goto out;
L
Linus Torvalds 已提交
88 89 90
	if (rpci->nreaders) {
		list_add_tail(&msg->list, &rpci->pipe);
		rpci->pipelen += msg->len;
91
		res = 0;
L
Linus Torvalds 已提交
92 93 94 95 96 97
	} else if (rpci->flags & RPC_PIPE_WAIT_FOR_OPEN) {
		if (list_empty(&rpci->pipe))
			schedule_delayed_work(&rpci->queue_timeout,
					RPC_UPCALL_TIMEOUT);
		list_add_tail(&msg->list, &rpci->pipe);
		rpci->pipelen += msg->len;
98 99 100
		res = 0;
	}
out:
101
	spin_unlock(&inode->i_lock);
L
Linus Torvalds 已提交
102 103 104 105
	wake_up(&rpci->waitq);
	return res;
}

106 107 108 109 110 111
static inline void
rpc_inode_setowner(struct inode *inode, void *private)
{
	RPC_I(inode)->private = private;
}

L
Linus Torvalds 已提交
112 113 114 115
static void
rpc_close_pipes(struct inode *inode)
{
	struct rpc_inode *rpci = RPC_I(inode);
116
	struct rpc_pipe_ops *ops;
L
Linus Torvalds 已提交
117

118
	mutex_lock(&inode->i_mutex);
119 120 121 122 123
	ops = rpci->ops;
	if (ops != NULL) {
		LIST_HEAD(free_list);

		spin_lock(&inode->i_lock);
L
Linus Torvalds 已提交
124
		rpci->nreaders = 0;
125 126 127
		list_splice_init(&rpci->in_upcall, &free_list);
		list_splice_init(&rpci->pipe, &free_list);
		rpci->pipelen = 0;
L
Linus Torvalds 已提交
128
		rpci->ops = NULL;
129 130 131 132 133 134 135
		spin_unlock(&inode->i_lock);
		rpc_purge_list(rpci, &free_list, ops->destroy_msg, -EPIPE);
		rpci->nwriters = 0;
		if (ops->release_pipe)
			ops->release_pipe(inode);
		cancel_delayed_work(&rpci->queue_timeout);
		flush_scheduled_work();
L
Linus Torvalds 已提交
136
	}
137
	rpc_inode_setowner(inode, NULL);
138
	mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162
}

static struct inode *
rpc_alloc_inode(struct super_block *sb)
{
	struct rpc_inode *rpci;
	rpci = (struct rpc_inode *)kmem_cache_alloc(rpc_inode_cachep, SLAB_KERNEL);
	if (!rpci)
		return NULL;
	return &rpci->vfs_inode;
}

static void
rpc_destroy_inode(struct inode *inode)
{
	kmem_cache_free(rpc_inode_cachep, RPC_I(inode));
}

static int
rpc_pipe_open(struct inode *inode, struct file *filp)
{
	struct rpc_inode *rpci = RPC_I(inode);
	int res = -ENXIO;

163
	mutex_lock(&inode->i_mutex);
L
Linus Torvalds 已提交
164 165 166 167 168 169 170
	if (rpci->ops != NULL) {
		if (filp->f_mode & FMODE_READ)
			rpci->nreaders ++;
		if (filp->f_mode & FMODE_WRITE)
			rpci->nwriters ++;
		res = 0;
	}
171
	mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
172 173 174 175 176 177
	return res;
}

static int
rpc_pipe_release(struct inode *inode, struct file *filp)
{
178
	struct rpc_inode *rpci = RPC_I(inode);
L
Linus Torvalds 已提交
179 180
	struct rpc_pipe_msg *msg;

181
	mutex_lock(&inode->i_mutex);
L
Linus Torvalds 已提交
182 183 184 185
	if (rpci->ops == NULL)
		goto out;
	msg = (struct rpc_pipe_msg *)filp->private_data;
	if (msg != NULL) {
186
		spin_lock(&inode->i_lock);
187
		msg->errno = -EAGAIN;
188 189
		list_del(&msg->list);
		spin_unlock(&inode->i_lock);
L
Linus Torvalds 已提交
190 191 192 193
		rpci->ops->destroy_msg(msg);
	}
	if (filp->f_mode & FMODE_WRITE)
		rpci->nwriters --;
194
	if (filp->f_mode & FMODE_READ) {
L
Linus Torvalds 已提交
195
		rpci->nreaders --;
196 197 198 199 200 201 202 203 204 205
		if (rpci->nreaders == 0) {
			LIST_HEAD(free_list);
			spin_lock(&inode->i_lock);
			list_splice_init(&rpci->pipe, &free_list);
			rpci->pipelen = 0;
			spin_unlock(&inode->i_lock);
			rpc_purge_list(rpci, &free_list,
					rpci->ops->destroy_msg, -EAGAIN);
		}
	}
L
Linus Torvalds 已提交
206 207 208
	if (rpci->ops->release_pipe)
		rpci->ops->release_pipe(inode);
out:
209
	mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
210 211 212 213 214 215 216 217 218 219 220
	return 0;
}

static ssize_t
rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct rpc_inode *rpci = RPC_I(inode);
	struct rpc_pipe_msg *msg;
	int res = 0;

221
	mutex_lock(&inode->i_mutex);
L
Linus Torvalds 已提交
222 223 224 225 226 227
	if (rpci->ops == NULL) {
		res = -EPIPE;
		goto out_unlock;
	}
	msg = filp->private_data;
	if (msg == NULL) {
228
		spin_lock(&inode->i_lock);
L
Linus Torvalds 已提交
229 230 231 232 233 234 235 236 237
		if (!list_empty(&rpci->pipe)) {
			msg = list_entry(rpci->pipe.next,
					struct rpc_pipe_msg,
					list);
			list_move(&msg->list, &rpci->in_upcall);
			rpci->pipelen -= msg->len;
			filp->private_data = msg;
			msg->copied = 0;
		}
238
		spin_unlock(&inode->i_lock);
L
Linus Torvalds 已提交
239 240 241 242 243 244 245
		if (msg == NULL)
			goto out_unlock;
	}
	/* NOTE: it is up to the callback to update msg->copied */
	res = rpci->ops->upcall(filp, msg, buf, len);
	if (res < 0 || msg->len == msg->copied) {
		filp->private_data = NULL;
246 247 248
		spin_lock(&inode->i_lock);
		list_del(&msg->list);
		spin_unlock(&inode->i_lock);
L
Linus Torvalds 已提交
249 250 251
		rpci->ops->destroy_msg(msg);
	}
out_unlock:
252
	mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
253 254 255 256 257 258 259 260 261 262
	return res;
}

static ssize_t
rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct rpc_inode *rpci = RPC_I(inode);
	int res;

263
	mutex_lock(&inode->i_mutex);
L
Linus Torvalds 已提交
264 265 266
	res = -EPIPE;
	if (rpci->ops != NULL)
		res = rpci->ops->downcall(filp, buf, len);
267
	mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344
	return res;
}

static unsigned int
rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
{
	struct rpc_inode *rpci;
	unsigned int mask = 0;

	rpci = RPC_I(filp->f_dentry->d_inode);
	poll_wait(filp, &rpci->waitq, wait);

	mask = POLLOUT | POLLWRNORM;
	if (rpci->ops == NULL)
		mask |= POLLERR | POLLHUP;
	if (!list_empty(&rpci->pipe))
		mask |= POLLIN | POLLRDNORM;
	return mask;
}

static int
rpc_pipe_ioctl(struct inode *ino, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	struct rpc_inode *rpci = RPC_I(filp->f_dentry->d_inode);
	int len;

	switch (cmd) {
	case FIONREAD:
		if (rpci->ops == NULL)
			return -EPIPE;
		len = rpci->pipelen;
		if (filp->private_data) {
			struct rpc_pipe_msg *msg;
			msg = (struct rpc_pipe_msg *)filp->private_data;
			len += msg->len - msg->copied;
		}
		return put_user(len, (int __user *)arg);
	default:
		return -EINVAL;
	}
}

static struct file_operations rpc_pipe_fops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.read		= rpc_pipe_read,
	.write		= rpc_pipe_write,
	.poll		= rpc_pipe_poll,
	.ioctl		= rpc_pipe_ioctl,
	.open		= rpc_pipe_open,
	.release	= rpc_pipe_release,
};

static int
rpc_show_info(struct seq_file *m, void *v)
{
	struct rpc_clnt *clnt = m->private;

	seq_printf(m, "RPC server: %s\n", clnt->cl_server);
	seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_protname,
			clnt->cl_prog, clnt->cl_vers);
	seq_printf(m, "address: %u.%u.%u.%u\n",
			NIPQUAD(clnt->cl_xprt->addr.sin_addr.s_addr));
	seq_printf(m, "protocol: %s\n",
			clnt->cl_xprt->prot == IPPROTO_UDP ? "udp" : "tcp");
	return 0;
}

static int
rpc_info_open(struct inode *inode, struct file *file)
{
	struct rpc_clnt *clnt;
	int ret = single_open(file, rpc_show_info, NULL);

	if (!ret) {
		struct seq_file *m = file->private_data;
345
		mutex_lock(&inode->i_mutex);
L
Linus Torvalds 已提交
346 347 348 349 350 351 352 353
		clnt = RPC_I(inode)->private;
		if (clnt) {
			atomic_inc(&clnt->cl_users);
			m->private = clnt;
		} else {
			single_release(inode, file);
			ret = -EINVAL;
		}
354
		mutex_unlock(&inode->i_mutex);
L
Linus Torvalds 已提交
355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448
	}
	return ret;
}

static int
rpc_info_release(struct inode *inode, struct file *file)
{
	struct seq_file *m = file->private_data;
	struct rpc_clnt *clnt = (struct rpc_clnt *)m->private;

	if (clnt)
		rpc_release_client(clnt);
	return single_release(inode, file);
}

static struct file_operations rpc_info_operations = {
	.owner		= THIS_MODULE,
	.open		= rpc_info_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= rpc_info_release,
};


/*
 * We have a single directory with 1 node in it.
 */
enum {
	RPCAUTH_Root = 1,
	RPCAUTH_lockd,
	RPCAUTH_mount,
	RPCAUTH_nfs,
	RPCAUTH_portmap,
	RPCAUTH_statd,
	RPCAUTH_RootEOF
};

/*
 * Description of fs contents.
 */
struct rpc_filelist {
	char *name;
	struct file_operations *i_fop;
	int mode;
};

static struct rpc_filelist files[] = {
	[RPCAUTH_lockd] = {
		.name = "lockd",
		.mode = S_IFDIR | S_IRUGO | S_IXUGO,
	},
	[RPCAUTH_mount] = {
		.name = "mount",
		.mode = S_IFDIR | S_IRUGO | S_IXUGO,
	},
	[RPCAUTH_nfs] = {
		.name = "nfs",
		.mode = S_IFDIR | S_IRUGO | S_IXUGO,
	},
	[RPCAUTH_portmap] = {
		.name = "portmap",
		.mode = S_IFDIR | S_IRUGO | S_IXUGO,
	},
	[RPCAUTH_statd] = {
		.name = "statd",
		.mode = S_IFDIR | S_IRUGO | S_IXUGO,
	},
};

enum {
	RPCAUTH_info = 2,
	RPCAUTH_EOF
};

static struct rpc_filelist authfiles[] = {
	[RPCAUTH_info] = {
		.name = "info",
		.i_fop = &rpc_info_operations,
		.mode = S_IFREG | S_IRUSR,
	},
};

static int
rpc_get_mount(void)
{
	return simple_pin_fs("rpc_pipefs", &rpc_mount, &rpc_mount_count);
}

static void
rpc_put_mount(void)
{
	simple_release_fs(&rpc_mount, &rpc_mount_count);
}

449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480
static int
rpc_lookup_parent(char *path, struct nameidata *nd)
{
	if (path[0] == '\0')
		return -ENOENT;
	if (rpc_get_mount()) {
		printk(KERN_WARNING "%s: %s failed to mount "
			       "pseudofilesystem \n", __FILE__, __FUNCTION__);
		return -ENODEV;
	}
	nd->mnt = mntget(rpc_mount);
	nd->dentry = dget(rpc_mount->mnt_root);
	nd->last_type = LAST_ROOT;
	nd->flags = LOOKUP_PARENT;
	nd->depth = 0;

	if (path_walk(path, nd)) {
		printk(KERN_WARNING "%s: %s failed to find path %s\n",
				__FILE__, __FUNCTION__, path);
		rpc_put_mount();
		return -ENOENT;
	}
	return 0;
}

static void
rpc_release_path(struct nameidata *nd)
{
	path_release(nd);
	rpc_put_mount();
}

L
Linus Torvalds 已提交
481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513
static struct inode *
rpc_get_inode(struct super_block *sb, int mode)
{
	struct inode *inode = new_inode(sb);
	if (!inode)
		return NULL;
	inode->i_mode = mode;
	inode->i_uid = inode->i_gid = 0;
	inode->i_blksize = PAGE_CACHE_SIZE;
	inode->i_blocks = 0;
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	switch(mode & S_IFMT) {
		case S_IFDIR:
			inode->i_fop = &simple_dir_operations;
			inode->i_op = &simple_dir_inode_operations;
			inode->i_nlink++;
		default:
			break;
	}
	return inode;
}

/*
 * FIXME: This probably has races.
 */
static void
rpc_depopulate(struct dentry *parent)
{
	struct inode *dir = parent->d_inode;
	struct list_head *pos, *next;
	struct dentry *dentry, *dvec[10];
	int n = 0;

514
	mutex_lock(&dir->i_mutex);
L
Linus Torvalds 已提交
515 516 517
repeat:
	spin_lock(&dcache_lock);
	list_for_each_safe(pos, next, &parent->d_subdirs) {
E
Eric Dumazet 已提交
518
		dentry = list_entry(pos, struct dentry, d_u.d_child);
L
Linus Torvalds 已提交
519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541
		spin_lock(&dentry->d_lock);
		if (!d_unhashed(dentry)) {
			dget_locked(dentry);
			__d_drop(dentry);
			spin_unlock(&dentry->d_lock);
			dvec[n++] = dentry;
			if (n == ARRAY_SIZE(dvec))
				break;
		} else
			spin_unlock(&dentry->d_lock);
	}
	spin_unlock(&dcache_lock);
	if (n) {
		do {
			dentry = dvec[--n];
			if (dentry->d_inode) {
				rpc_close_pipes(dentry->d_inode);
				simple_unlink(dir, dentry);
			}
			dput(dentry);
		} while (n);
		goto repeat;
	}
542
	mutex_unlock(&dir->i_mutex);
L
Linus Torvalds 已提交
543 544 545 546 547 548 549 550 551 552 553 554
}

static int
rpc_populate(struct dentry *parent,
		struct rpc_filelist *files,
		int start, int eof)
{
	struct inode *inode, *dir = parent->d_inode;
	void *private = RPC_I(dir)->private;
	struct dentry *dentry;
	int mode, i;

555
	mutex_lock(&dir->i_mutex);
L
Linus Torvalds 已提交
556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574
	for (i = start; i < eof; i++) {
		dentry = d_alloc_name(parent, files[i].name);
		if (!dentry)
			goto out_bad;
		mode = files[i].mode;
		inode = rpc_get_inode(dir->i_sb, mode);
		if (!inode) {
			dput(dentry);
			goto out_bad;
		}
		inode->i_ino = i;
		if (files[i].i_fop)
			inode->i_fop = files[i].i_fop;
		if (private)
			rpc_inode_setowner(inode, private);
		if (S_ISDIR(mode))
			dir->i_nlink++;
		d_add(dentry, inode);
	}
575
	mutex_unlock(&dir->i_mutex);
L
Linus Torvalds 已提交
576 577
	return 0;
out_bad:
578
	mutex_unlock(&dir->i_mutex);
L
Linus Torvalds 已提交
579 580 581 582 583
	printk(KERN_WARNING "%s: %s failed to populate directory %s\n",
			__FILE__, __FUNCTION__, parent->d_name.name);
	return -ENOMEM;
}

584 585
static int
__rpc_mkdir(struct inode *dir, struct dentry *dentry)
L
Linus Torvalds 已提交
586 587
{
	struct inode *inode;
588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606

	inode = rpc_get_inode(dir->i_sb, S_IFDIR | S_IRUSR | S_IXUSR);
	if (!inode)
		goto out_err;
	inode->i_ino = iunique(dir->i_sb, 100);
	d_instantiate(dentry, inode);
	dir->i_nlink++;
	inode_dir_notify(dir, DN_CREATE);
	rpc_get_mount();
	return 0;
out_err:
	printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %s\n",
			__FILE__, __FUNCTION__, dentry->d_name.name);
	return -ENOMEM;
}

static int
__rpc_rmdir(struct inode *dir, struct dentry *dentry)
{
L
Linus Torvalds 已提交
607 608
	int error;

609
	shrink_dcache_parent(dentry);
610
	if (dentry->d_inode)
611 612 613 614 615 616 617 618 619 620
		rpc_close_pipes(dentry->d_inode);
	if ((error = simple_rmdir(dir, dentry)) != 0)
		return error;
	if (!error) {
		inode_dir_notify(dir, DN_DELETE);
		d_drop(dentry);
		rpc_put_mount();
	}
	return 0;
}
L
Linus Torvalds 已提交
621

622 623 624 625 626 627
static struct dentry *
rpc_lookup_negative(char *path, struct nameidata *nd)
{
	struct dentry *dentry;
	struct inode *dir;
	int error;
628

629 630 631
	if ((error = rpc_lookup_parent(path, nd)) != 0)
		return ERR_PTR(error);
	dir = nd->dentry->d_inode;
632
	mutex_lock(&dir->i_mutex);
633
	dentry = lookup_hash(nd);
L
Linus Torvalds 已提交
634
	if (IS_ERR(dentry))
635
		goto out_err;
L
Linus Torvalds 已提交
636
	if (dentry->d_inode) {
637
		dput(dentry);
L
Linus Torvalds 已提交
638
		dentry = ERR_PTR(-EEXIST);
639
		goto out_err;
L
Linus Torvalds 已提交
640
	}
641 642
	return dentry;
out_err:
643
	mutex_unlock(&dir->i_mutex);
644 645 646
	rpc_release_path(nd);
	return dentry;
}
647

L
Linus Torvalds 已提交
648

649 650 651 652 653 654 655 656 657 658 659 660 661 662 663
struct dentry *
rpc_mkdir(char *path, struct rpc_clnt *rpc_client)
{
	struct nameidata nd;
	struct dentry *dentry;
	struct inode *dir;
	int error;

	dentry = rpc_lookup_negative(path, &nd);
	if (IS_ERR(dentry))
		return dentry;
	dir = nd.dentry->d_inode;
	if ((error = __rpc_mkdir(dir, dentry)) != 0)
		goto err_dput;
	RPC_I(dentry->d_inode)->private = rpc_client;
L
Linus Torvalds 已提交
664 665 666
	error = rpc_populate(dentry, authfiles,
			RPCAUTH_info, RPCAUTH_EOF);
	if (error)
667 668
		goto err_depopulate;
out:
669
	mutex_unlock(&dir->i_mutex);
670
	rpc_release_path(&nd);
671
	return dentry;
672 673 674 675 676 677 678 679 680
err_depopulate:
	rpc_depopulate(dentry);
	__rpc_rmdir(dir, dentry);
err_dput:
	dput(dentry);
	printk(KERN_WARNING "%s: %s() failed to create directory %s (errno = %d)\n",
			__FILE__, __FUNCTION__, path, error);
	dentry = ERR_PTR(error);
	goto out;
L
Linus Torvalds 已提交
681 682
}

683 684
int
rpc_rmdir(char *path)
L
Linus Torvalds 已提交
685
{
686 687 688 689
	struct nameidata nd;
	struct dentry *dentry;
	struct inode *dir;
	int error;
690

691 692 693
	if ((error = rpc_lookup_parent(path, &nd)) != 0)
		return error;
	dir = nd.dentry->d_inode;
694
	mutex_lock(&dir->i_mutex);
695
	dentry = lookup_hash(&nd);
696 697 698
	if (IS_ERR(dentry)) {
		error = PTR_ERR(dentry);
		goto out_release;
699
	}
700 701 702 703
	rpc_depopulate(dentry);
	error = __rpc_rmdir(dir, dentry);
	dput(dentry);
out_release:
704
	mutex_unlock(&dir->i_mutex);
705 706
	rpc_release_path(&nd);
	return error;
L
Linus Torvalds 已提交
707 708 709
}

struct dentry *
710
rpc_mkpipe(char *path, void *private, struct rpc_pipe_ops *ops, int flags)
L
Linus Torvalds 已提交
711
{
712
	struct nameidata nd;
L
Linus Torvalds 已提交
713
	struct dentry *dentry;
714
	struct inode *dir, *inode;
L
Linus Torvalds 已提交
715 716
	struct rpc_inode *rpci;

717
	dentry = rpc_lookup_negative(path, &nd);
L
Linus Torvalds 已提交
718
	if (IS_ERR(dentry))
719 720 721 722 723
		return dentry;
	dir = nd.dentry->d_inode;
	inode = rpc_get_inode(dir->i_sb, S_IFSOCK | S_IRUSR | S_IWUSR);
	if (!inode)
		goto err_dput;
L
Linus Torvalds 已提交
724 725
	inode->i_ino = iunique(dir->i_sb, 100);
	inode->i_fop = &rpc_pipe_fops;
726
	d_instantiate(dentry, inode);
L
Linus Torvalds 已提交
727 728 729 730 731
	rpci = RPC_I(inode);
	rpci->private = private;
	rpci->flags = flags;
	rpci->ops = ops;
	inode_dir_notify(dir, DN_CREATE);
732
out:
733
	mutex_unlock(&dir->i_mutex);
734
	rpc_release_path(&nd);
L
Linus Torvalds 已提交
735
	return dentry;
736
err_dput:
L
Linus Torvalds 已提交
737
	dput(dentry);
738 739 740 741
	dentry = ERR_PTR(-ENOMEM);
	printk(KERN_WARNING "%s: %s() failed to create pipe %s (errno = %d)\n",
			__FILE__, __FUNCTION__, path, -ENOMEM);
	goto out;
L
Linus Torvalds 已提交
742 743
}

744 745
int
rpc_unlink(char *path)
L
Linus Torvalds 已提交
746
{
747 748 749 750
	struct nameidata nd;
	struct dentry *dentry;
	struct inode *dir;
	int error;
L
Linus Torvalds 已提交
751

752 753 754
	if ((error = rpc_lookup_parent(path, &nd)) != 0)
		return error;
	dir = nd.dentry->d_inode;
755
	mutex_lock(&dir->i_mutex);
756
	dentry = lookup_hash(&nd);
757 758 759 760 761
	if (IS_ERR(dentry)) {
		error = PTR_ERR(dentry);
		goto out_release;
	}
	d_drop(dentry);
L
Linus Torvalds 已提交
762 763
	if (dentry->d_inode) {
		rpc_close_pipes(dentry->d_inode);
764
		error = simple_unlink(dir, dentry);
L
Linus Torvalds 已提交
765
	}
766 767 768
	dput(dentry);
	inode_dir_notify(dir, DN_DELETE);
out_release:
769
	mutex_unlock(&dir->i_mutex);
770 771
	rpc_release_path(&nd);
	return error;
L
Linus Torvalds 已提交
772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
}

/*
 * populate the filesystem
 */
static struct super_operations s_ops = {
	.alloc_inode	= rpc_alloc_inode,
	.destroy_inode	= rpc_destroy_inode,
	.statfs		= simple_statfs,
};

#define RPCAUTH_GSSMAGIC 0x67596969

static int
rpc_fill_super(struct super_block *sb, void *data, int silent)
{
	struct inode *inode;
	struct dentry *root;

	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = RPCAUTH_GSSMAGIC;
	sb->s_op = &s_ops;
	sb->s_time_gran = 1;

	inode = rpc_get_inode(sb, S_IFDIR | 0755);
	if (!inode)
		return -ENOMEM;
	root = d_alloc_root(inode);
	if (!root) {
		iput(inode);
		return -ENOMEM;
	}
	if (rpc_populate(root, files, RPCAUTH_Root + 1, RPCAUTH_RootEOF))
		goto out;
	sb->s_root = root;
	return 0;
out:
	d_genocide(root);
	dput(root);
	return -ENOMEM;
}

static struct super_block *
rpc_get_sb(struct file_system_type *fs_type,
		int flags, const char *dev_name, void *data)
{
	return get_sb_single(fs_type, flags, data, rpc_fill_super);
}

static struct file_system_type rpc_pipe_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "rpc_pipefs",
	.get_sb		= rpc_get_sb,
	.kill_sb	= kill_litter_super,
};

static void
init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
{
	struct rpc_inode *rpci = (struct rpc_inode *) foo;

	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    SLAB_CTOR_CONSTRUCTOR) {
		inode_init_once(&rpci->vfs_inode);
		rpci->private = NULL;
		rpci->nreaders = 0;
		rpci->nwriters = 0;
		INIT_LIST_HEAD(&rpci->in_upcall);
		INIT_LIST_HEAD(&rpci->pipe);
		rpci->pipelen = 0;
		init_waitqueue_head(&rpci->waitq);
		INIT_WORK(&rpci->queue_timeout, rpc_timeout_upcall_queue, rpci);
		rpci->ops = NULL;
	}
}

int register_rpc_pipefs(void)
{
	rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
                                             sizeof(struct rpc_inode),
                                             0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT,
                                             init_once, NULL);
	if (!rpc_inode_cachep)
		return -ENOMEM;
	register_filesystem(&rpc_pipe_fs_type);
	return 0;
}

void unregister_rpc_pipefs(void)
{
	if (kmem_cache_destroy(rpc_inode_cachep))
		printk(KERN_WARNING "RPC: unable to free inode cache\n");
	unregister_filesystem(&rpc_pipe_fs_type);
}