Linux Audio

Check our new training course

Loading...
v3.1
 
   1/*
   2 *  linux/fs/9p/vfs_inode.c
   3 *
   4 * This file contains vfs inode ops for the 9P2000 protocol.
   5 *
   6 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   7 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
   8 *
   9 *  This program is free software; you can redistribute it and/or modify
  10 *  it under the terms of the GNU General Public License version 2
  11 *  as published by the Free Software Foundation.
  12 *
  13 *  This program is distributed in the hope that it will be useful,
  14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 *  GNU General Public License for more details.
  17 *
  18 *  You should have received a copy of the GNU General Public License
  19 *  along with this program; if not, write to:
  20 *  Free Software Foundation
  21 *  51 Franklin Street, Fifth Floor
  22 *  Boston, MA  02111-1301  USA
  23 *
  24 */
  25
 
 
  26#include <linux/module.h>
  27#include <linux/errno.h>
  28#include <linux/fs.h>
  29#include <linux/file.h>
  30#include <linux/pagemap.h>
  31#include <linux/stat.h>
  32#include <linux/string.h>
  33#include <linux/inet.h>
  34#include <linux/namei.h>
  35#include <linux/idr.h>
  36#include <linux/sched.h>
  37#include <linux/slab.h>
  38#include <linux/xattr.h>
  39#include <linux/posix_acl.h>
  40#include <net/9p/9p.h>
  41#include <net/9p/client.h>
  42
  43#include "v9fs.h"
  44#include "v9fs_vfs.h"
  45#include "fid.h"
  46#include "cache.h"
  47#include "xattr.h"
  48#include "acl.h"
  49
  50static const struct inode_operations v9fs_dir_inode_operations;
  51static const struct inode_operations v9fs_dir_inode_operations_dotu;
  52static const struct inode_operations v9fs_file_inode_operations;
  53static const struct inode_operations v9fs_symlink_inode_operations;
  54
  55/**
  56 * unixmode2p9mode - convert unix mode bits to plan 9
  57 * @v9ses: v9fs session information
  58 * @mode: mode to convert
  59 *
  60 */
  61
  62static int unixmode2p9mode(struct v9fs_session_info *v9ses, int mode)
  63{
  64	int res;
 
  65	res = mode & 0777;
  66	if (S_ISDIR(mode))
  67		res |= P9_DMDIR;
  68	if (v9fs_proto_dotu(v9ses)) {
  69		if (S_ISLNK(mode))
  70			res |= P9_DMSYMLINK;
  71		if (v9ses->nodev == 0) {
  72			if (S_ISSOCK(mode))
  73				res |= P9_DMSOCKET;
  74			if (S_ISFIFO(mode))
  75				res |= P9_DMNAMEDPIPE;
  76			if (S_ISBLK(mode))
  77				res |= P9_DMDEVICE;
  78			if (S_ISCHR(mode))
  79				res |= P9_DMDEVICE;
  80		}
  81
  82		if ((mode & S_ISUID) == S_ISUID)
  83			res |= P9_DMSETUID;
  84		if ((mode & S_ISGID) == S_ISGID)
  85			res |= P9_DMSETGID;
  86		if ((mode & S_ISVTX) == S_ISVTX)
  87			res |= P9_DMSETVTX;
  88		if ((mode & P9_DMLINK))
  89			res |= P9_DMLINK;
  90	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  91
 
 
 
 
 
 
  92	return res;
  93}
  94
  95/**
  96 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
  97 * @v9ses: v9fs session information
  98 * @stat: p9_wstat from which mode need to be derived
  99 * @rdev: major number, minor number in case of device files.
 100 *
 101 */
 102static int p9mode2unixmode(struct v9fs_session_info *v9ses,
 103			   struct p9_wstat *stat, dev_t *rdev)
 104{
 105	int res;
 106	int mode = stat->mode;
 107
 108	res = mode & S_IALLUGO;
 109	*rdev = 0;
 
 110
 111	if ((mode & P9_DMDIR) == P9_DMDIR)
 112		res |= S_IFDIR;
 113	else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
 114		res |= S_IFLNK;
 115	else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
 116		 && (v9ses->nodev == 0))
 117		res |= S_IFSOCK;
 118	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
 119		 && (v9ses->nodev == 0))
 120		res |= S_IFIFO;
 121	else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
 122		 && (v9ses->nodev == 0)) {
 123		char type = 0, ext[32];
 124		int major = -1, minor = -1;
 125
 126		strncpy(ext, stat->extension, sizeof(ext));
 127		sscanf(ext, "%c %u %u", &type, &major, &minor);
 
 
 
 
 
 128		switch (type) {
 129		case 'c':
 130			res |= S_IFCHR;
 131			break;
 132		case 'b':
 133			res |= S_IFBLK;
 134			break;
 135		default:
 136			P9_DPRINTK(P9_DEBUG_ERROR,
 137				"Unknown special type %c %s\n", type,
 138				stat->extension);
 139		};
 140		*rdev = MKDEV(major, minor);
 141	} else
 142		res |= S_IFREG;
 143
 144	if (v9fs_proto_dotu(v9ses)) {
 145		if ((mode & P9_DMSETUID) == P9_DMSETUID)
 146			res |= S_ISUID;
 147
 148		if ((mode & P9_DMSETGID) == P9_DMSETGID)
 149			res |= S_ISGID;
 150
 151		if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
 152			res |= S_ISVTX;
 153	}
 154	return res;
 155}
 156
 157/**
 158 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
 159 * @uflags: flags to convert
 160 * @extended: if .u extensions are active
 161 */
 162
 163int v9fs_uflags2omode(int uflags, int extended)
 164{
 165	int ret;
 166
 167	ret = 0;
 168	switch (uflags&3) {
 169	default:
 170	case O_RDONLY:
 171		ret = P9_OREAD;
 172		break;
 173
 174	case O_WRONLY:
 175		ret = P9_OWRITE;
 176		break;
 177
 178	case O_RDWR:
 179		ret = P9_ORDWR;
 180		break;
 181	}
 182
 183	if (uflags & O_TRUNC)
 184		ret |= P9_OTRUNC;
 185
 186	if (extended) {
 187		if (uflags & O_EXCL)
 188			ret |= P9_OEXCL;
 189
 190		if (uflags & O_APPEND)
 191			ret |= P9_OAPPEND;
 192	}
 193
 194	return ret;
 195}
 196
 197/**
 198 * v9fs_blank_wstat - helper function to setup a 9P stat structure
 199 * @wstat: structure to initialize
 200 *
 201 */
 202
 203void
 204v9fs_blank_wstat(struct p9_wstat *wstat)
 205{
 206	wstat->type = ~0;
 207	wstat->dev = ~0;
 208	wstat->qid.type = ~0;
 209	wstat->qid.version = ~0;
 210	*((long long *)&wstat->qid.path) = ~0;
 211	wstat->mode = ~0;
 212	wstat->atime = ~0;
 213	wstat->mtime = ~0;
 214	wstat->length = ~0;
 215	wstat->name = NULL;
 216	wstat->uid = NULL;
 217	wstat->gid = NULL;
 218	wstat->muid = NULL;
 219	wstat->n_uid = ~0;
 220	wstat->n_gid = ~0;
 221	wstat->n_muid = ~0;
 222	wstat->extension = NULL;
 223}
 224
 225/**
 226 * v9fs_alloc_inode - helper function to allocate an inode
 227 *
 228 */
 229struct inode *v9fs_alloc_inode(struct super_block *sb)
 230{
 231	struct v9fs_inode *v9inode;
 232	v9inode = (struct v9fs_inode *)kmem_cache_alloc(v9fs_inode_cache,
 233							GFP_KERNEL);
 234	if (!v9inode)
 235		return NULL;
 236#ifdef CONFIG_9P_FSCACHE
 237	v9inode->fscache = NULL;
 238	spin_lock_init(&v9inode->fscache_lock);
 239#endif
 240	v9inode->writeback_fid = NULL;
 241	v9inode->cache_validity = 0;
 242	mutex_init(&v9inode->v_mutex);
 243	return &v9inode->vfs_inode;
 244}
 245
 246/**
 247 * v9fs_destroy_inode - destroy an inode
 248 *
 249 */
 250
 251static void v9fs_i_callback(struct rcu_head *head)
 252{
 253	struct inode *inode = container_of(head, struct inode, i_rcu);
 254	INIT_LIST_HEAD(&inode->i_dentry);
 255	kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
 256}
 257
 258void v9fs_destroy_inode(struct inode *inode)
 
 
 
 259{
 260	call_rcu(&inode->i_rcu, v9fs_i_callback);
 
 261}
 262
 263int v9fs_init_inode(struct v9fs_session_info *v9ses,
 264		    struct inode *inode, int mode, dev_t rdev)
 265{
 266	int err = 0;
 267
 268	inode_init_owner(inode, NULL, mode);
 269	inode->i_blocks = 0;
 270	inode->i_rdev = rdev;
 271	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 272	inode->i_mapping->a_ops = &v9fs_addr_operations;
 
 273
 274	switch (mode & S_IFMT) {
 275	case S_IFIFO:
 276	case S_IFBLK:
 277	case S_IFCHR:
 278	case S_IFSOCK:
 279		if (v9fs_proto_dotl(v9ses)) {
 280			inode->i_op = &v9fs_file_inode_operations_dotl;
 281			inode->i_fop = &v9fs_file_operations_dotl;
 282		} else if (v9fs_proto_dotu(v9ses)) {
 283			inode->i_op = &v9fs_file_inode_operations;
 284			inode->i_fop = &v9fs_file_operations;
 285		} else {
 286			P9_DPRINTK(P9_DEBUG_ERROR,
 287				   "special files without extended mode\n");
 288			err = -EINVAL;
 289			goto error;
 290		}
 291		init_special_inode(inode, inode->i_mode, inode->i_rdev);
 292		break;
 293	case S_IFREG:
 294		if (v9fs_proto_dotl(v9ses)) {
 295			inode->i_op = &v9fs_file_inode_operations_dotl;
 296			if (v9ses->cache)
 297				inode->i_fop =
 298					&v9fs_cached_file_operations_dotl;
 299			else
 300				inode->i_fop = &v9fs_file_operations_dotl;
 301		} else {
 302			inode->i_op = &v9fs_file_inode_operations;
 303			if (v9ses->cache)
 304				inode->i_fop = &v9fs_cached_file_operations;
 305			else
 306				inode->i_fop = &v9fs_file_operations;
 307		}
 308
 309		break;
 310	case S_IFLNK:
 311		if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
 312			P9_DPRINTK(P9_DEBUG_ERROR, "extended modes used with "
 313						"legacy protocol.\n");
 314			err = -EINVAL;
 315			goto error;
 316		}
 317
 318		if (v9fs_proto_dotl(v9ses))
 319			inode->i_op = &v9fs_symlink_inode_operations_dotl;
 320		else
 321			inode->i_op = &v9fs_symlink_inode_operations;
 322
 323		break;
 324	case S_IFDIR:
 325		inc_nlink(inode);
 326		if (v9fs_proto_dotl(v9ses))
 327			inode->i_op = &v9fs_dir_inode_operations_dotl;
 328		else if (v9fs_proto_dotu(v9ses))
 329			inode->i_op = &v9fs_dir_inode_operations_dotu;
 330		else
 331			inode->i_op = &v9fs_dir_inode_operations;
 332
 333		if (v9fs_proto_dotl(v9ses))
 334			inode->i_fop = &v9fs_dir_operations_dotl;
 335		else
 336			inode->i_fop = &v9fs_dir_operations;
 337
 338		break;
 339	default:
 340		P9_DPRINTK(P9_DEBUG_ERROR, "BAD mode 0x%x S_IFMT 0x%x\n",
 341			   mode, mode & S_IFMT);
 342		err = -EINVAL;
 343		goto error;
 344	}
 345error:
 346	return err;
 347
 348}
 349
 350/**
 351 * v9fs_get_inode - helper function to setup an inode
 352 * @sb: superblock
 353 * @mode: mode to setup inode with
 354 *
 355 */
 356
 357struct inode *v9fs_get_inode(struct super_block *sb, int mode, dev_t rdev)
 358{
 359	int err;
 360	struct inode *inode;
 361	struct v9fs_session_info *v9ses = sb->s_fs_info;
 362
 363	P9_DPRINTK(P9_DEBUG_VFS, "super block: %p mode: %o\n", sb, mode);
 364
 365	inode = new_inode(sb);
 366	if (!inode) {
 367		P9_EPRINTK(KERN_WARNING, "Problem allocating inode\n");
 368		return ERR_PTR(-ENOMEM);
 369	}
 370	err = v9fs_init_inode(v9ses, inode, mode, rdev);
 371	if (err) {
 372		iput(inode);
 373		return ERR_PTR(err);
 374	}
 375	return inode;
 376}
 377
 378/*
 379static struct v9fs_fid*
 380v9fs_clone_walk(struct v9fs_session_info *v9ses, u32 fid, struct dentry *dentry)
 381{
 382	int err;
 383	int nfid;
 384	struct v9fs_fid *ret;
 385	struct v9fs_fcall *fcall;
 386
 387	nfid = v9fs_get_idpool(&v9ses->fidpool);
 388	if (nfid < 0) {
 389		eprintk(KERN_WARNING, "no free fids available\n");
 390		return ERR_PTR(-ENOSPC);
 391	}
 392
 393	err = v9fs_t_walk(v9ses, fid, nfid, (char *) dentry->d_name.name,
 394		&fcall);
 395
 396	if (err < 0) {
 397		if (fcall && fcall->id == RWALK)
 398			goto clunk_fid;
 399
 400		PRINT_FCALL_ERROR("walk error", fcall);
 401		v9fs_put_idpool(nfid, &v9ses->fidpool);
 402		goto error;
 403	}
 404
 405	kfree(fcall);
 406	fcall = NULL;
 407	ret = v9fs_fid_create(v9ses, nfid);
 408	if (!ret) {
 409		err = -ENOMEM;
 410		goto clunk_fid;
 411	}
 412
 413	err = v9fs_fid_insert(ret, dentry);
 414	if (err < 0) {
 415		v9fs_fid_destroy(ret);
 416		goto clunk_fid;
 417	}
 418
 419	return ret;
 420
 421clunk_fid:
 422	v9fs_t_clunk(v9ses, nfid);
 423
 424error:
 425	kfree(fcall);
 426	return ERR_PTR(err);
 427}
 428*/
 429
 430
 431/**
 432 * v9fs_clear_inode - release an inode
 433 * @inode: inode to release
 434 *
 435 */
 436void v9fs_evict_inode(struct inode *inode)
 437{
 438	struct v9fs_inode *v9inode = V9FS_I(inode);
 
 
 
 
 
 439
 440	truncate_inode_pages(inode->i_mapping, 0);
 441	end_writeback(inode);
 442	filemap_fdatawrite(inode->i_mapping);
 
 
 443
 444#ifdef CONFIG_9P_FSCACHE
 445	v9fs_cache_inode_put_cookie(inode);
 
 446#endif
 447	/* clunk the fid stashed in writeback_fid */
 448	if (v9inode->writeback_fid) {
 449		p9_client_clunk(v9inode->writeback_fid);
 450		v9inode->writeback_fid = NULL;
 451	}
 452}
 453
 454static int v9fs_test_inode(struct inode *inode, void *data)
 455{
 456	int umode;
 457	dev_t rdev;
 458	struct v9fs_inode *v9inode = V9FS_I(inode);
 459	struct p9_wstat *st = (struct p9_wstat *)data;
 460	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
 461
 462	umode = p9mode2unixmode(v9ses, st, &rdev);
 463	/* don't match inode of different type */
 464	if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
 465		return 0;
 466
 467	/* compare qid details */
 468	if (memcmp(&v9inode->qid.version,
 469		   &st->qid.version, sizeof(v9inode->qid.version)))
 470		return 0;
 471
 472	if (v9inode->qid.type != st->qid.type)
 473		return 0;
 
 
 
 474	return 1;
 475}
 476
 477static int v9fs_test_new_inode(struct inode *inode, void *data)
 478{
 479	return 0;
 480}
 481
 482static int v9fs_set_inode(struct inode *inode,  void *data)
 483{
 484	struct v9fs_inode *v9inode = V9FS_I(inode);
 485	struct p9_wstat *st = (struct p9_wstat *)data;
 486
 487	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
 488	return 0;
 489}
 490
 491static struct inode *v9fs_qid_iget(struct super_block *sb,
 492				   struct p9_qid *qid,
 493				   struct p9_wstat *st,
 494				   int new)
 495{
 496	dev_t rdev;
 497	int retval, umode;
 498	unsigned long i_ino;
 499	struct inode *inode;
 500	struct v9fs_session_info *v9ses = sb->s_fs_info;
 501	int (*test)(struct inode *, void *);
 502
 503	if (new)
 504		test = v9fs_test_new_inode;
 505	else
 506		test = v9fs_test_inode;
 507
 508	i_ino = v9fs_qid2ino(qid);
 509	inode = iget5_locked(sb, i_ino, test, v9fs_set_inode, st);
 510	if (!inode)
 511		return ERR_PTR(-ENOMEM);
 512	if (!(inode->i_state & I_NEW))
 513		return inode;
 514	/*
 515	 * initialize the inode with the stat info
 516	 * FIXME!! we may need support for stale inodes
 517	 * later.
 518	 */
 519	inode->i_ino = i_ino;
 520	umode = p9mode2unixmode(v9ses, st, &rdev);
 521	retval = v9fs_init_inode(v9ses, inode, umode, rdev);
 522	if (retval)
 523		goto error;
 524
 525	v9fs_stat2inode(st, inode, sb);
 526#ifdef CONFIG_9P_FSCACHE
 527	v9fs_cache_inode_get_cookie(inode);
 528#endif
 529	unlock_new_inode(inode);
 530	return inode;
 531error:
 532	unlock_new_inode(inode);
 533	iput(inode);
 534	return ERR_PTR(retval);
 535
 536}
 537
 538struct inode *
 539v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 540		    struct super_block *sb, int new)
 541{
 542	struct p9_wstat *st;
 543	struct inode *inode = NULL;
 544
 545	st = p9_client_stat(fid);
 546	if (IS_ERR(st))
 547		return ERR_CAST(st);
 548
 549	inode = v9fs_qid_iget(sb, &st->qid, st, new);
 550	p9stat_free(st);
 551	kfree(st);
 552	return inode;
 553}
 554
 555/**
 556 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
 557 * plan 9 AT flag.
 558 * @flags: flags to convert
 559 */
 560static int v9fs_at_to_dotl_flags(int flags)
 561{
 562	int rflags = 0;
 
 563	if (flags & AT_REMOVEDIR)
 564		rflags |= P9_DOTL_AT_REMOVEDIR;
 
 565	return rflags;
 566}
 567
 568/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 569 * v9fs_remove - helper function to remove files and directories
 570 * @dir: directory inode that is being deleted
 571 * @dentry:  dentry that is being deleted
 572 * @rmdir: removing a directory
 573 *
 574 */
 575
 576static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
 577{
 578	struct inode *inode;
 579	int retval = -EOPNOTSUPP;
 580	struct p9_fid *v9fid, *dfid;
 581	struct v9fs_session_info *v9ses;
 582
 583	P9_DPRINTK(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
 584		   dir, dentry, flags);
 585
 586	v9ses = v9fs_inode2v9ses(dir);
 587	inode = dentry->d_inode;
 588	dfid = v9fs_fid_lookup(dentry->d_parent);
 589	if (IS_ERR(dfid)) {
 590		retval = PTR_ERR(dfid);
 591		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
 592		return retval;
 593	}
 594	if (v9fs_proto_dotl(v9ses))
 595		retval = p9_client_unlinkat(dfid, dentry->d_name.name,
 596					    v9fs_at_to_dotl_flags(flags));
 
 597	if (retval == -EOPNOTSUPP) {
 598		/* Try the one based on path */
 599		v9fid = v9fs_fid_clone(dentry);
 600		if (IS_ERR(v9fid))
 601			return PTR_ERR(v9fid);
 602		retval = p9_client_remove(v9fid);
 603	}
 604	if (!retval) {
 605		/*
 606		 * directories on unlink should have zero
 607		 * link count
 608		 */
 609		if (flags & AT_REMOVEDIR) {
 610			clear_nlink(inode);
 611			drop_nlink(dir);
 612		} else
 613			drop_nlink(inode);
 614
 615		v9fs_invalidate_inode_attr(inode);
 616		v9fs_invalidate_inode_attr(dir);
 
 
 
 
 617	}
 618	return retval;
 619}
 620
 621/**
 622 * v9fs_create - Create a file
 623 * @v9ses: session information
 624 * @dir: directory that dentry is being created in
 625 * @dentry:  dentry that is being created
 626 * @extension: 9p2000.u extension string to support devices, etc.
 627 * @perm: create permissions
 628 * @mode: open mode
 629 *
 630 */
 631static struct p9_fid *
 632v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 633		struct dentry *dentry, char *extension, u32 perm, u8 mode)
 634{
 635	int err;
 636	char *name;
 637	struct p9_fid *dfid, *ofid, *fid;
 638	struct inode *inode;
 639
 640	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 641
 642	err = 0;
 643	ofid = NULL;
 644	fid = NULL;
 645	name = (char *) dentry->d_name.name;
 646	dfid = v9fs_fid_lookup(dentry->d_parent);
 647	if (IS_ERR(dfid)) {
 648		err = PTR_ERR(dfid);
 649		P9_DPRINTK(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
 650		return ERR_PTR(err);
 651	}
 652
 653	/* clone a fid to use for creation */
 654	ofid = p9_client_walk(dfid, 0, NULL, 1);
 655	if (IS_ERR(ofid)) {
 656		err = PTR_ERR(ofid);
 657		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 658		return ERR_PTR(err);
 659	}
 660
 661	err = p9_client_fcreate(ofid, name, perm, mode, extension);
 662	if (err < 0) {
 663		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
 664		goto error;
 665	}
 666
 667	/* now walk from the parent so we can get unopened fid */
 668	fid = p9_client_walk(dfid, 1, &name, 1);
 669	if (IS_ERR(fid)) {
 670		err = PTR_ERR(fid);
 671		P9_DPRINTK(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 672		fid = NULL;
 673		goto error;
 674	}
 675
 676	/* instantiate inode and assign the unopened fid to the dentry */
 677	inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 678	if (IS_ERR(inode)) {
 679		err = PTR_ERR(inode);
 680		P9_DPRINTK(P9_DEBUG_VFS, "inode creation failed %d\n", err);
 681		goto error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 682	}
 683	err = v9fs_fid_add(dentry, fid);
 684	if (err < 0)
 685		goto error;
 686	d_instantiate(dentry, inode);
 687	return ofid;
 688error:
 689	if (ofid)
 690		p9_client_clunk(ofid);
 691
 692	if (fid)
 693		p9_client_clunk(fid);
 694
 695	return ERR_PTR(err);
 696}
 697
 698/**
 699 * v9fs_vfs_create - VFS hook to create files
 700 * @dir: directory inode that is being created
 701 * @dentry:  dentry that is being deleted
 702 * @mode: create permissions
 703 * @nd: path information
 
 
 
 
 704 *
 705 */
 706
 707static int
 708v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 709		struct nameidata *nd)
 710{
 711	int err;
 712	u32 perm;
 713	int flags;
 714	struct file *filp;
 715	struct v9fs_inode *v9inode;
 716	struct v9fs_session_info *v9ses;
 717	struct p9_fid *fid, *inode_fid;
 718
 719	err = 0;
 720	fid = NULL;
 721	v9ses = v9fs_inode2v9ses(dir);
 722	perm = unixmode2p9mode(v9ses, mode);
 723	if (nd)
 724		flags = nd->intent.open.flags;
 725	else
 726		flags = O_RDWR;
 727
 728	fid = v9fs_create(v9ses, dir, dentry, NULL, perm,
 729				v9fs_uflags2omode(flags,
 730						v9fs_proto_dotu(v9ses)));
 731	if (IS_ERR(fid)) {
 732		err = PTR_ERR(fid);
 733		fid = NULL;
 734		goto error;
 735	}
 736
 737	v9fs_invalidate_inode_attr(dir);
 738	/* if we are opening a file, assign the open fid to the file */
 739	if (nd) {
 740		v9inode = V9FS_I(dentry->d_inode);
 741		mutex_lock(&v9inode->v_mutex);
 742		if (v9ses->cache && !v9inode->writeback_fid &&
 743		    ((flags & O_ACCMODE) != O_RDONLY)) {
 744			/*
 745			 * clone a fid and add it to writeback_fid
 746			 * we do it during open time instead of
 747			 * page dirty time via write_begin/page_mkwrite
 748			 * because we want write after unlink usecase
 749			 * to work.
 750			 */
 751			inode_fid = v9fs_writeback_fid(dentry);
 752			if (IS_ERR(inode_fid)) {
 753				err = PTR_ERR(inode_fid);
 754				mutex_unlock(&v9inode->v_mutex);
 755				goto error;
 756			}
 757			v9inode->writeback_fid = (void *) inode_fid;
 758		}
 759		mutex_unlock(&v9inode->v_mutex);
 760		filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
 761		if (IS_ERR(filp)) {
 762			err = PTR_ERR(filp);
 763			goto error;
 764		}
 765
 766		filp->private_data = fid;
 767#ifdef CONFIG_9P_FSCACHE
 768		if (v9ses->cache)
 769			v9fs_cache_inode_set_cookie(dentry->d_inode, filp);
 770#endif
 771	} else
 772		p9_client_clunk(fid);
 773
 774	return 0;
 775
 776error:
 777	if (fid)
 778		p9_client_clunk(fid);
 779
 780	return err;
 781}
 782
 783/**
 784 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 
 785 * @dir:  inode that is being unlinked
 786 * @dentry: dentry that is being unlinked
 787 * @mode: mode for new directory
 788 *
 789 */
 790
 791static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 
 792{
 793	int err;
 794	u32 perm;
 795	struct p9_fid *fid;
 796	struct v9fs_session_info *v9ses;
 797
 798	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
 799	err = 0;
 800	v9ses = v9fs_inode2v9ses(dir);
 801	perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 802	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
 803	if (IS_ERR(fid)) {
 804		err = PTR_ERR(fid);
 805		fid = NULL;
 806	} else {
 807		inc_nlink(dir);
 808		v9fs_invalidate_inode_attr(dir);
 809	}
 810
 811	if (fid)
 812		p9_client_clunk(fid);
 813
 814	return err;
 815}
 816
 817/**
 818 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 819 * @dir:  inode that is being walked from
 820 * @dentry: dentry that is being walked to?
 821 * @nameidata: path data
 822 *
 823 */
 824
 825struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 826				      struct nameidata *nameidata)
 827{
 828	struct dentry *res;
 829	struct super_block *sb;
 830	struct v9fs_session_info *v9ses;
 831	struct p9_fid *dfid, *fid;
 832	struct inode *inode;
 833	char *name;
 834	int result = 0;
 835
 836	P9_DPRINTK(P9_DEBUG_VFS, "dir: %p dentry: (%s) %p nameidata: %p\n",
 837		dir, dentry->d_name.name, dentry, nameidata);
 838
 839	if (dentry->d_name.len > NAME_MAX)
 840		return ERR_PTR(-ENAMETOOLONG);
 841
 842	sb = dir->i_sb;
 843	v9ses = v9fs_inode2v9ses(dir);
 844	/* We can walk d_parent because we hold the dir->i_mutex */
 845	dfid = v9fs_fid_lookup(dentry->d_parent);
 846	if (IS_ERR(dfid))
 847		return ERR_CAST(dfid);
 848
 849	name = (char *) dentry->d_name.name;
 850	fid = p9_client_walk(dfid, 1, &name, 1);
 851	if (IS_ERR(fid)) {
 852		result = PTR_ERR(fid);
 853		if (result == -ENOENT) {
 854			inode = NULL;
 855			goto inst_out;
 856		}
 857
 858		return ERR_PTR(result);
 859	}
 860	/*
 861	 * Make sure we don't use a wrong inode due to parallel
 862	 * unlink. For cached mode create calls request for new
 863	 * inode. But with cache disabled, lookup should do this.
 864	 */
 865	if (v9ses->cache)
 
 
 
 
 
 
 
 866		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 867	else
 868		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 869	if (IS_ERR(inode)) {
 870		result = PTR_ERR(inode);
 871		inode = NULL;
 872		goto error;
 873	}
 874	result = v9fs_fid_add(dentry, fid);
 875	if (result < 0)
 876		goto error_iput;
 877inst_out:
 878	/*
 879	 * If we had a rename on the server and a parallel lookup
 880	 * for the new name, then make sure we instantiate with
 881	 * the new name. ie look up for a/b, while on server somebody
 882	 * moved b under k and client parallely did a lookup for
 883	 * k/b.
 884	 */
 885	res = d_materialise_unique(dentry, inode);
 886	if (!IS_ERR(res))
 887		return res;
 888	result = PTR_ERR(res);
 889error_iput:
 890	iput(inode);
 891error:
 892	p9_client_clunk(fid);
 
 
 
 893
 894	return ERR_PTR(result);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 895}
 896
 897/**
 898 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 899 * @i:  inode that is being unlinked
 900 * @d: dentry that is being unlinked
 901 *
 902 */
 903
 904int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 905{
 906	return v9fs_remove(i, d, 0);
 907}
 908
 909/**
 910 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 911 * @i:  inode that is being unlinked
 912 * @d: dentry that is being unlinked
 913 *
 914 */
 915
 916int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 917{
 918	return v9fs_remove(i, d, AT_REMOVEDIR);
 919}
 920
 921/**
 922 * v9fs_vfs_rename - VFS hook to rename an inode
 
 923 * @old_dir:  old dir inode
 924 * @old_dentry: old dentry
 925 * @new_dir: new dir inode
 926 * @new_dentry: new dentry
 
 927 *
 928 */
 929
 930int
 931v9fs_vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 932		struct inode *new_dir, struct dentry *new_dentry)
 
 933{
 934	int retval;
 935	struct inode *old_inode;
 936	struct inode *new_inode;
 937	struct v9fs_session_info *v9ses;
 938	struct p9_fid *oldfid;
 939	struct p9_fid *olddirfid;
 940	struct p9_fid *newdirfid;
 941	struct p9_wstat wstat;
 942
 943	P9_DPRINTK(P9_DEBUG_VFS, "\n");
 944	retval = 0;
 945	old_inode = old_dentry->d_inode;
 946	new_inode = new_dentry->d_inode;
 
 
 947	v9ses = v9fs_inode2v9ses(old_inode);
 948	oldfid = v9fs_fid_lookup(old_dentry);
 949	if (IS_ERR(oldfid))
 950		return PTR_ERR(oldfid);
 951
 952	olddirfid = v9fs_fid_clone(old_dentry->d_parent);
 
 
 
 
 953	if (IS_ERR(olddirfid)) {
 954		retval = PTR_ERR(olddirfid);
 955		goto done;
 956	}
 957
 958	newdirfid = v9fs_fid_clone(new_dentry->d_parent);
 
 
 
 
 959	if (IS_ERR(newdirfid)) {
 960		retval = PTR_ERR(newdirfid);
 961		goto clunk_olddir;
 962	}
 963
 964	down_write(&v9ses->rename_sem);
 965	if (v9fs_proto_dotl(v9ses)) {
 966		retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
 967					    newdirfid, new_dentry->d_name.name);
 968		if (retval == -EOPNOTSUPP)
 969			retval = p9_client_rename(oldfid, newdirfid,
 970						  new_dentry->d_name.name);
 971		if (retval != -EOPNOTSUPP)
 972			goto clunk_newdir;
 973	}
 974	if (old_dentry->d_parent != new_dentry->d_parent) {
 975		/*
 976		 * 9P .u can only handle file rename in the same directory
 977		 */
 978
 979		P9_DPRINTK(P9_DEBUG_ERROR,
 980				"old dir and new dir are different\n");
 981		retval = -EXDEV;
 982		goto clunk_newdir;
 983	}
 984	v9fs_blank_wstat(&wstat);
 985	wstat.muid = v9ses->uname;
 986	wstat.name = (char *) new_dentry->d_name.name;
 987	retval = p9_client_wstat(oldfid, &wstat);
 988
 989clunk_newdir:
 990	if (!retval) {
 991		if (new_inode) {
 992			if (S_ISDIR(new_inode->i_mode))
 993				clear_nlink(new_inode);
 994			else
 995				drop_nlink(new_inode);
 996		}
 997		if (S_ISDIR(old_inode->i_mode)) {
 998			if (!new_inode)
 999				inc_nlink(new_dir);
1000			drop_nlink(old_dir);
1001		}
1002		v9fs_invalidate_inode_attr(old_inode);
1003		v9fs_invalidate_inode_attr(old_dir);
1004		v9fs_invalidate_inode_attr(new_dir);
1005
1006		/* successful rename */
1007		d_move(old_dentry, new_dentry);
1008	}
1009	up_write(&v9ses->rename_sem);
1010	p9_client_clunk(newdirfid);
1011
1012clunk_olddir:
1013	p9_client_clunk(olddirfid);
1014
1015done:
1016	return retval;
1017}
1018
1019/**
1020 * v9fs_vfs_getattr - retrieve file metadata
1021 * @mnt: mount information
1022 * @dentry: file to get attributes on
1023 * @stat: metadata structure to populate
 
 
1024 *
1025 */
1026
1027static int
1028v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
1029		 struct kstat *stat)
1030{
1031	int err;
 
1032	struct v9fs_session_info *v9ses;
1033	struct p9_fid *fid;
1034	struct p9_wstat *st;
1035
1036	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
1037	err = -EPERM;
1038	v9ses = v9fs_dentry2v9ses(dentry);
1039	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
1040		generic_fillattr(dentry->d_inode, stat);
1041		return 0;
 
 
 
 
 
 
 
 
1042	}
1043	fid = v9fs_fid_lookup(dentry);
1044	if (IS_ERR(fid))
1045		return PTR_ERR(fid);
1046
1047	st = p9_client_stat(fid);
 
1048	if (IS_ERR(st))
1049		return PTR_ERR(st);
1050
1051	v9fs_stat2inode(st, dentry->d_inode, dentry->d_inode->i_sb);
1052	generic_fillattr(dentry->d_inode, stat);
1053
1054	p9stat_free(st);
1055	kfree(st);
1056	return 0;
1057}
1058
1059/**
1060 * v9fs_vfs_setattr - set file metadata
 
1061 * @dentry: file whose metadata to set
1062 * @iattr: metadata assignment structure
1063 *
1064 */
1065
1066static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 
1067{
1068	int retval;
 
1069	struct v9fs_session_info *v9ses;
1070	struct p9_fid *fid;
1071	struct p9_wstat wstat;
1072
1073	P9_DPRINTK(P9_DEBUG_VFS, "\n");
1074	retval = inode_change_ok(dentry->d_inode, iattr);
1075	if (retval)
1076		return retval;
1077
1078	retval = -EPERM;
1079	v9ses = v9fs_dentry2v9ses(dentry);
1080	fid = v9fs_fid_lookup(dentry);
1081	if(IS_ERR(fid))
 
 
 
 
 
 
 
1082		return PTR_ERR(fid);
1083
1084	v9fs_blank_wstat(&wstat);
1085	if (iattr->ia_valid & ATTR_MODE)
1086		wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1087
1088	if (iattr->ia_valid & ATTR_MTIME)
1089		wstat.mtime = iattr->ia_mtime.tv_sec;
1090
1091	if (iattr->ia_valid & ATTR_ATIME)
1092		wstat.atime = iattr->ia_atime.tv_sec;
1093
1094	if (iattr->ia_valid & ATTR_SIZE)
1095		wstat.length = iattr->ia_size;
1096
1097	if (v9fs_proto_dotu(v9ses)) {
1098		if (iattr->ia_valid & ATTR_UID)
1099			wstat.n_uid = iattr->ia_uid;
1100
1101		if (iattr->ia_valid & ATTR_GID)
1102			wstat.n_gid = iattr->ia_gid;
1103	}
1104
1105	/* Write all dirty data */
1106	if (S_ISREG(dentry->d_inode->i_mode))
1107		filemap_write_and_wait(dentry->d_inode->i_mapping);
 
 
 
 
1108
1109	retval = p9_client_wstat(fid, &wstat);
 
 
 
 
1110	if (retval < 0)
1111		return retval;
1112
1113	if ((iattr->ia_valid & ATTR_SIZE) &&
1114	    iattr->ia_size != i_size_read(dentry->d_inode))
1115		truncate_setsize(dentry->d_inode, iattr->ia_size);
 
 
 
 
 
 
 
 
 
 
1116
1117	v9fs_invalidate_inode_attr(dentry->d_inode);
1118
1119	setattr_copy(dentry->d_inode, iattr);
1120	mark_inode_dirty(dentry->d_inode);
1121	return 0;
1122}
1123
1124/**
1125 * v9fs_stat2inode - populate an inode structure with mistat info
1126 * @stat: Plan 9 metadata (mistat) structure
1127 * @inode: inode to populate
1128 * @sb: superblock of filesystem
 
1129 *
1130 */
1131
1132void
1133v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1134	struct super_block *sb)
1135{
1136	mode_t mode;
1137	char ext[32];
1138	char tag_name[14];
1139	unsigned int i_nlink;
1140	struct v9fs_session_info *v9ses = sb->s_fs_info;
1141	struct v9fs_inode *v9inode = V9FS_I(inode);
1142
1143	inode->i_nlink = 1;
1144
1145	inode->i_atime.tv_sec = stat->atime;
1146	inode->i_mtime.tv_sec = stat->mtime;
1147	inode->i_ctime.tv_sec = stat->mtime;
1148
1149	inode->i_uid = v9ses->dfltuid;
1150	inode->i_gid = v9ses->dfltgid;
1151
1152	if (v9fs_proto_dotu(v9ses)) {
1153		inode->i_uid = stat->n_uid;
1154		inode->i_gid = stat->n_gid;
1155	}
1156	if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1157		if (v9fs_proto_dotu(v9ses) && (stat->extension[0] != '\0')) {
 
1158			/*
1159			 * Hadlink support got added later to
1160			 * to the .u extension. So there can be
1161			 * server out there that doesn't support
1162			 * this even with .u extension. So check
1163			 * for non NULL stat->extension
1164			 */
1165			strncpy(ext, stat->extension, sizeof(ext));
1166			/* HARDLINKCOUNT %u */
1167			sscanf(ext, "%13s %u", tag_name, &i_nlink);
1168			if (!strncmp(tag_name, "HARDLINKCOUNT", 13))
1169				inode->i_nlink = i_nlink;
1170		}
1171	}
1172	mode = stat->mode & S_IALLUGO;
1173	mode |= inode->i_mode & ~S_IALLUGO;
1174	inode->i_mode = mode;
1175	i_size_write(inode, stat->length);
1176
 
 
 
1177	/* not real number of blocks, but 512 byte ones ... */
1178	inode->i_blocks = (i_size_read(inode) + 512 - 1) >> 9;
1179	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1180}
1181
1182/**
1183 * v9fs_qid2ino - convert qid into inode number
1184 * @qid: qid to hash
1185 *
1186 * BUG: potential for inode number collisions?
1187 */
1188
1189ino_t v9fs_qid2ino(struct p9_qid *qid)
1190{
1191	u64 path = qid->path + 2;
1192	ino_t i = 0;
1193
1194	if (sizeof(ino_t) == sizeof(path))
1195		memcpy(&i, &path, sizeof(ino_t));
1196	else
1197		i = (ino_t) (path ^ (path >> 32));
1198
1199	return i;
1200}
1201
1202/**
1203 * v9fs_readlink - read a symlink's location (internal version)
1204 * @dentry: dentry for symlink
1205 * @buffer: buffer to load symlink location into
1206 * @buflen: length of buffer
1207 *
1208 */
1209
1210static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 
 
1211{
1212	int retval;
1213
1214	struct v9fs_session_info *v9ses;
1215	struct p9_fid *fid;
1216	struct p9_wstat *st;
 
 
 
 
1217
1218	P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
1219	retval = -EPERM;
1220	v9ses = v9fs_dentry2v9ses(dentry);
 
 
 
 
1221	fid = v9fs_fid_lookup(dentry);
1222	if (IS_ERR(fid))
1223		return PTR_ERR(fid);
1224
1225	if (!v9fs_proto_dotu(v9ses))
1226		return -EBADF;
1227
1228	st = p9_client_stat(fid);
 
1229	if (IS_ERR(st))
1230		return PTR_ERR(st);
1231
1232	if (!(st->mode & P9_DMSYMLINK)) {
1233		retval = -EINVAL;
1234		goto done;
1235	}
1236
1237	/* copy extension buffer into buffer */
1238	strncpy(buffer, st->extension, buflen);
 
 
1239
1240	P9_DPRINTK(P9_DEBUG_VFS,
1241		"%s -> %s (%s)\n", dentry->d_name.name, st->extension, buffer);
1242
1243	retval = strnlen(buffer, buflen);
1244done:
1245	p9stat_free(st);
1246	kfree(st);
1247	return retval;
1248}
1249
1250/**
1251 * v9fs_vfs_follow_link - follow a symlink path
1252 * @dentry: dentry for symlink
1253 * @nd: nameidata
1254 *
1255 */
1256
1257static void *v9fs_vfs_follow_link(struct dentry *dentry, struct nameidata *nd)
1258{
1259	int len = 0;
1260	char *link = __getname();
1261
1262	P9_DPRINTK(P9_DEBUG_VFS, "%s n", dentry->d_name.name);
1263
1264	if (!link)
1265		link = ERR_PTR(-ENOMEM);
1266	else {
1267		len = v9fs_readlink(dentry, link, PATH_MAX);
1268
1269		if (len < 0) {
1270			__putname(link);
1271			link = ERR_PTR(len);
1272		} else
1273			link[min(len, PATH_MAX-1)] = 0;
1274	}
1275	nd_set_link(nd, link);
1276
1277	return NULL;
1278}
1279
1280/**
1281 * v9fs_vfs_put_link - release a symlink path
1282 * @dentry: dentry for symlink
1283 * @nd: nameidata
1284 * @p: unused
1285 *
1286 */
1287
1288void
1289v9fs_vfs_put_link(struct dentry *dentry, struct nameidata *nd, void *p)
1290{
1291	char *s = nd_get_link(nd);
1292
1293	P9_DPRINTK(P9_DEBUG_VFS, " %s %s\n", dentry->d_name.name,
1294		IS_ERR(s) ? "<error>" : s);
1295	if (!IS_ERR(s))
1296		__putname(s);
1297}
1298
1299/**
1300 * v9fs_vfs_mkspecial - create a special file
1301 * @dir: inode to create special file in
1302 * @dentry: dentry to create
1303 * @mode: mode to create special file
1304 * @extension: 9p2000.u format extension string representing special file
1305 *
1306 */
1307
1308static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1309	int mode, const char *extension)
1310{
1311	u32 perm;
1312	struct p9_fid *fid;
1313	struct v9fs_session_info *v9ses;
1314
1315	v9ses = v9fs_inode2v9ses(dir);
1316	if (!v9fs_proto_dotu(v9ses)) {
1317		P9_DPRINTK(P9_DEBUG_ERROR, "not extended\n");
1318		return -EPERM;
1319	}
1320
1321	perm = unixmode2p9mode(v9ses, mode);
1322	fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1323								P9_OREAD);
1324	if (IS_ERR(fid))
1325		return PTR_ERR(fid);
1326
1327	v9fs_invalidate_inode_attr(dir);
1328	p9_client_clunk(fid);
1329	return 0;
1330}
1331
1332/**
1333 * v9fs_vfs_symlink - helper function to create symlinks
 
1334 * @dir: directory inode containing symlink
1335 * @dentry: dentry for symlink
1336 * @symname: symlink data
1337 *
1338 * See Also: 9P2000.u RFC for more information
1339 *
1340 */
1341
1342static int
1343v9fs_vfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
 
1344{
1345	P9_DPRINTK(P9_DEBUG_VFS, " %lu,%s,%s\n", dir->i_ino,
1346					dentry->d_name.name, symname);
1347
1348	return v9fs_vfs_mkspecial(dir, dentry, S_IFLNK, symname);
1349}
1350
 
 
1351/**
1352 * v9fs_vfs_link - create a hardlink
1353 * @old_dentry: dentry for file to link to
1354 * @dir: inode destination for new link
1355 * @dentry: dentry for link
1356 *
1357 */
1358
1359static int
1360v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1361	      struct dentry *dentry)
1362{
1363	int retval;
1364	char *name;
1365	struct p9_fid *oldfid;
1366
1367	P9_DPRINTK(P9_DEBUG_VFS,
1368		" %lu,%s,%s\n", dir->i_ino, dentry->d_name.name,
1369		old_dentry->d_name.name);
1370
1371	oldfid = v9fs_fid_clone(old_dentry);
1372	if (IS_ERR(oldfid))
1373		return PTR_ERR(oldfid);
1374
1375	name = __getname();
1376	if (unlikely(!name)) {
1377		retval = -ENOMEM;
1378		goto clunk_fid;
1379	}
1380
1381	sprintf(name, "%d\n", oldfid->fid);
1382	retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
1383	__putname(name);
1384	if (!retval) {
1385		v9fs_refresh_inode(oldfid, old_dentry->d_inode);
1386		v9fs_invalidate_inode_attr(dir);
1387	}
1388clunk_fid:
1389	p9_client_clunk(oldfid);
1390	return retval;
1391}
1392
1393/**
1394 * v9fs_vfs_mknod - create a special file
 
1395 * @dir: inode destination for new link
1396 * @dentry: dentry for file
1397 * @mode: mode for creation
1398 * @rdev: device associated with special file
1399 *
1400 */
1401
1402static int
1403v9fs_vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
 
1404{
 
1405	int retval;
1406	char *name;
 
1407
1408	P9_DPRINTK(P9_DEBUG_VFS,
1409		" %lu,%s mode: %x MAJOR: %u MINOR: %u\n", dir->i_ino,
1410		dentry->d_name.name, mode, MAJOR(rdev), MINOR(rdev));
1411
1412	if (!new_valid_dev(rdev))
1413		return -EINVAL;
1414
1415	name = __getname();
1416	if (!name)
1417		return -ENOMEM;
1418	/* build extension */
1419	if (S_ISBLK(mode))
1420		sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1421	else if (S_ISCHR(mode))
1422		sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1423	else if (S_ISFIFO(mode))
1424		*name = 0;
1425	else if (S_ISSOCK(mode))
1426		*name = 0;
1427	else {
1428		__putname(name);
1429		return -EINVAL;
1430	}
1431
1432	retval = v9fs_vfs_mkspecial(dir, dentry, mode, name);
1433	__putname(name);
1434
1435	return retval;
1436}
1437
1438int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1439{
1440	int umode;
1441	dev_t rdev;
1442	loff_t i_size;
1443	struct p9_wstat *st;
1444	struct v9fs_session_info *v9ses;
 
1445
1446	v9ses = v9fs_inode2v9ses(inode);
1447	st = p9_client_stat(fid);
1448	if (IS_ERR(st))
1449		return PTR_ERR(st);
1450	/*
1451	 * Don't update inode if the file type is different
1452	 */
1453	umode = p9mode2unixmode(v9ses, st, &rdev);
1454	if ((inode->i_mode & S_IFMT) != (umode & S_IFMT))
1455		goto out;
1456
1457	spin_lock(&inode->i_lock);
1458	/*
1459	 * We don't want to refresh inode->i_size,
1460	 * because we may have cached data
1461	 */
1462	i_size = inode->i_size;
1463	v9fs_stat2inode(st, inode, inode->i_sb);
1464	if (v9ses->cache)
1465		inode->i_size = i_size;
1466	spin_unlock(&inode->i_lock);
1467out:
1468	p9stat_free(st);
1469	kfree(st);
1470	return 0;
1471}
1472
1473static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1474	.create = v9fs_vfs_create,
1475	.lookup = v9fs_vfs_lookup,
 
1476	.symlink = v9fs_vfs_symlink,
1477	.link = v9fs_vfs_link,
1478	.unlink = v9fs_vfs_unlink,
1479	.mkdir = v9fs_vfs_mkdir,
1480	.rmdir = v9fs_vfs_rmdir,
1481	.mknod = v9fs_vfs_mknod,
1482	.rename = v9fs_vfs_rename,
1483	.getattr = v9fs_vfs_getattr,
1484	.setattr = v9fs_vfs_setattr,
1485};
1486
1487static const struct inode_operations v9fs_dir_inode_operations = {
1488	.create = v9fs_vfs_create,
1489	.lookup = v9fs_vfs_lookup,
 
1490	.unlink = v9fs_vfs_unlink,
1491	.mkdir = v9fs_vfs_mkdir,
1492	.rmdir = v9fs_vfs_rmdir,
1493	.mknod = v9fs_vfs_mknod,
1494	.rename = v9fs_vfs_rename,
1495	.getattr = v9fs_vfs_getattr,
1496	.setattr = v9fs_vfs_setattr,
1497};
1498
1499static const struct inode_operations v9fs_file_inode_operations = {
1500	.getattr = v9fs_vfs_getattr,
1501	.setattr = v9fs_vfs_setattr,
1502};
1503
1504static const struct inode_operations v9fs_symlink_inode_operations = {
1505	.readlink = generic_readlink,
1506	.follow_link = v9fs_vfs_follow_link,
1507	.put_link = v9fs_vfs_put_link,
1508	.getattr = v9fs_vfs_getattr,
1509	.setattr = v9fs_vfs_setattr,
1510};
1511
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
 
 
   3 * This file contains vfs inode ops for the 9P2000 protocol.
   4 *
   5 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
   6 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   7 */
   8
   9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
  11#include <linux/module.h>
  12#include <linux/errno.h>
  13#include <linux/fs.h>
  14#include <linux/file.h>
  15#include <linux/pagemap.h>
  16#include <linux/stat.h>
  17#include <linux/string.h>
 
  18#include <linux/namei.h>
 
  19#include <linux/sched.h>
  20#include <linux/slab.h>
  21#include <linux/xattr.h>
  22#include <linux/posix_acl.h>
  23#include <net/9p/9p.h>
  24#include <net/9p/client.h>
  25
  26#include "v9fs.h"
  27#include "v9fs_vfs.h"
  28#include "fid.h"
  29#include "cache.h"
  30#include "xattr.h"
  31#include "acl.h"
  32
  33static const struct inode_operations v9fs_dir_inode_operations;
  34static const struct inode_operations v9fs_dir_inode_operations_dotu;
  35static const struct inode_operations v9fs_file_inode_operations;
  36static const struct inode_operations v9fs_symlink_inode_operations;
  37
  38/**
  39 * unixmode2p9mode - convert unix mode bits to plan 9
  40 * @v9ses: v9fs session information
  41 * @mode: mode to convert
  42 *
  43 */
  44
  45static u32 unixmode2p9mode(struct v9fs_session_info *v9ses, umode_t mode)
  46{
  47	int res;
  48
  49	res = mode & 0777;
  50	if (S_ISDIR(mode))
  51		res |= P9_DMDIR;
  52	if (v9fs_proto_dotu(v9ses)) {
 
 
  53		if (v9ses->nodev == 0) {
  54			if (S_ISSOCK(mode))
  55				res |= P9_DMSOCKET;
  56			if (S_ISFIFO(mode))
  57				res |= P9_DMNAMEDPIPE;
  58			if (S_ISBLK(mode))
  59				res |= P9_DMDEVICE;
  60			if (S_ISCHR(mode))
  61				res |= P9_DMDEVICE;
  62		}
  63
  64		if ((mode & S_ISUID) == S_ISUID)
  65			res |= P9_DMSETUID;
  66		if ((mode & S_ISGID) == S_ISGID)
  67			res |= P9_DMSETGID;
  68		if ((mode & S_ISVTX) == S_ISVTX)
  69			res |= P9_DMSETVTX;
 
 
  70	}
  71	return res;
  72}
  73
  74/**
  75 * p9mode2perm- convert plan9 mode bits to unix permission bits
  76 * @v9ses: v9fs session information
  77 * @stat: p9_wstat from which mode need to be derived
  78 *
  79 */
  80static int p9mode2perm(struct v9fs_session_info *v9ses,
  81		       struct p9_wstat *stat)
  82{
  83	int res;
  84	int mode = stat->mode;
  85
  86	res = mode & 0777; /* S_IRWXUGO */
  87	if (v9fs_proto_dotu(v9ses)) {
  88		if ((mode & P9_DMSETUID) == P9_DMSETUID)
  89			res |= S_ISUID;
  90
  91		if ((mode & P9_DMSETGID) == P9_DMSETGID)
  92			res |= S_ISGID;
  93
  94		if ((mode & P9_DMSETVTX) == P9_DMSETVTX)
  95			res |= S_ISVTX;
  96	}
  97	return res;
  98}
  99
 100/**
 101 * p9mode2unixmode- convert plan9 mode bits to unix mode bits
 102 * @v9ses: v9fs session information
 103 * @stat: p9_wstat from which mode need to be derived
 104 * @rdev: major number, minor number in case of device files.
 105 *
 106 */
 107static umode_t p9mode2unixmode(struct v9fs_session_info *v9ses,
 108			       struct p9_wstat *stat, dev_t *rdev)
 109{
 110	int res, r;
 111	u32 mode = stat->mode;
 112
 
 113	*rdev = 0;
 114	res = p9mode2perm(v9ses, stat);
 115
 116	if ((mode & P9_DMDIR) == P9_DMDIR)
 117		res |= S_IFDIR;
 118	else if ((mode & P9_DMSYMLINK) && (v9fs_proto_dotu(v9ses)))
 119		res |= S_IFLNK;
 120	else if ((mode & P9_DMSOCKET) && (v9fs_proto_dotu(v9ses))
 121		 && (v9ses->nodev == 0))
 122		res |= S_IFSOCK;
 123	else if ((mode & P9_DMNAMEDPIPE) && (v9fs_proto_dotu(v9ses))
 124		 && (v9ses->nodev == 0))
 125		res |= S_IFIFO;
 126	else if ((mode & P9_DMDEVICE) && (v9fs_proto_dotu(v9ses))
 127		 && (v9ses->nodev == 0)) {
 128		char type = 0;
 129		int major = -1, minor = -1;
 130
 131		r = sscanf(stat->extension, "%c %i %i", &type, &major, &minor);
 132		if (r != 3) {
 133			p9_debug(P9_DEBUG_ERROR,
 134				 "invalid device string, umode will be bogus: %s\n",
 135				 stat->extension);
 136			return res;
 137		}
 138		switch (type) {
 139		case 'c':
 140			res |= S_IFCHR;
 141			break;
 142		case 'b':
 143			res |= S_IFBLK;
 144			break;
 145		default:
 146			p9_debug(P9_DEBUG_ERROR, "Unknown special type %c %s\n",
 147				 type, stat->extension);
 148		}
 
 149		*rdev = MKDEV(major, minor);
 150	} else
 151		res |= S_IFREG;
 152
 
 
 
 
 
 
 
 
 
 
 153	return res;
 154}
 155
 156/**
 157 * v9fs_uflags2omode- convert posix open flags to plan 9 mode bits
 158 * @uflags: flags to convert
 159 * @extended: if .u extensions are active
 160 */
 161
 162int v9fs_uflags2omode(int uflags, int extended)
 163{
 164	int ret;
 165
 
 166	switch (uflags&3) {
 167	default:
 168	case O_RDONLY:
 169		ret = P9_OREAD;
 170		break;
 171
 172	case O_WRONLY:
 173		ret = P9_OWRITE;
 174		break;
 175
 176	case O_RDWR:
 177		ret = P9_ORDWR;
 178		break;
 179	}
 180
 181	if (uflags & O_TRUNC)
 182		ret |= P9_OTRUNC;
 183
 184	if (extended) {
 185		if (uflags & O_EXCL)
 186			ret |= P9_OEXCL;
 187
 188		if (uflags & O_APPEND)
 189			ret |= P9_OAPPEND;
 190	}
 191
 192	return ret;
 193}
 194
 195/**
 196 * v9fs_blank_wstat - helper function to setup a 9P stat structure
 197 * @wstat: structure to initialize
 198 *
 199 */
 200
 201void
 202v9fs_blank_wstat(struct p9_wstat *wstat)
 203{
 204	wstat->type = ~0;
 205	wstat->dev = ~0;
 206	wstat->qid.type = ~0;
 207	wstat->qid.version = ~0;
 208	*((long long *)&wstat->qid.path) = ~0;
 209	wstat->mode = ~0;
 210	wstat->atime = ~0;
 211	wstat->mtime = ~0;
 212	wstat->length = ~0;
 213	wstat->name = NULL;
 214	wstat->uid = NULL;
 215	wstat->gid = NULL;
 216	wstat->muid = NULL;
 217	wstat->n_uid = INVALID_UID;
 218	wstat->n_gid = INVALID_GID;
 219	wstat->n_muid = INVALID_UID;
 220	wstat->extension = NULL;
 221}
 222
 223/**
 224 * v9fs_alloc_inode - helper function to allocate an inode
 225 * @sb: The superblock to allocate the inode from
 226 */
 227struct inode *v9fs_alloc_inode(struct super_block *sb)
 228{
 229	struct v9fs_inode *v9inode;
 230
 231	v9inode = alloc_inode_sb(sb, v9fs_inode_cache, GFP_KERNEL);
 232	if (!v9inode)
 233		return NULL;
 
 
 
 
 
 234	v9inode->cache_validity = 0;
 235	mutex_init(&v9inode->v_mutex);
 236	return &v9inode->netfs.inode;
 237}
 238
 239/**
 240 * v9fs_free_inode - destroy an inode
 241 * @inode: The inode to be freed
 242 */
 243
 244void v9fs_free_inode(struct inode *inode)
 245{
 
 
 246	kmem_cache_free(v9fs_inode_cache, V9FS_I(inode));
 247}
 248
 249/*
 250 * Set parameters for the netfs library
 251 */
 252void v9fs_set_netfs_context(struct inode *inode)
 253{
 254	struct v9fs_inode *v9inode = V9FS_I(inode);
 255	netfs_inode_init(&v9inode->netfs, &v9fs_req_ops, true);
 256}
 257
 258int v9fs_init_inode(struct v9fs_session_info *v9ses,
 259		    struct inode *inode, umode_t mode, dev_t rdev)
 260{
 261	int err = 0;
 262
 263	inode_init_owner(&nop_mnt_idmap, inode, NULL, mode);
 264	inode->i_blocks = 0;
 265	inode->i_rdev = rdev;
 266	simple_inode_init_ts(inode);
 267	inode->i_mapping->a_ops = &v9fs_addr_operations;
 268	inode->i_private = NULL;
 269
 270	switch (mode & S_IFMT) {
 271	case S_IFIFO:
 272	case S_IFBLK:
 273	case S_IFCHR:
 274	case S_IFSOCK:
 275		if (v9fs_proto_dotl(v9ses)) {
 276			inode->i_op = &v9fs_file_inode_operations_dotl;
 
 277		} else if (v9fs_proto_dotu(v9ses)) {
 278			inode->i_op = &v9fs_file_inode_operations;
 
 279		} else {
 280			p9_debug(P9_DEBUG_ERROR,
 281				 "special files without extended mode\n");
 282			err = -EINVAL;
 283			goto error;
 284		}
 285		init_special_inode(inode, inode->i_mode, inode->i_rdev);
 286		break;
 287	case S_IFREG:
 288		if (v9fs_proto_dotl(v9ses)) {
 289			inode->i_op = &v9fs_file_inode_operations_dotl;
 290			inode->i_fop = &v9fs_file_operations_dotl;
 
 
 
 
 291		} else {
 292			inode->i_op = &v9fs_file_inode_operations;
 293			inode->i_fop = &v9fs_file_operations;
 
 
 
 294		}
 295
 296		break;
 297	case S_IFLNK:
 298		if (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)) {
 299			p9_debug(P9_DEBUG_ERROR,
 300				 "extended modes used with legacy protocol\n");
 301			err = -EINVAL;
 302			goto error;
 303		}
 304
 305		if (v9fs_proto_dotl(v9ses))
 306			inode->i_op = &v9fs_symlink_inode_operations_dotl;
 307		else
 308			inode->i_op = &v9fs_symlink_inode_operations;
 309
 310		break;
 311	case S_IFDIR:
 312		inc_nlink(inode);
 313		if (v9fs_proto_dotl(v9ses))
 314			inode->i_op = &v9fs_dir_inode_operations_dotl;
 315		else if (v9fs_proto_dotu(v9ses))
 316			inode->i_op = &v9fs_dir_inode_operations_dotu;
 317		else
 318			inode->i_op = &v9fs_dir_inode_operations;
 319
 320		if (v9fs_proto_dotl(v9ses))
 321			inode->i_fop = &v9fs_dir_operations_dotl;
 322		else
 323			inode->i_fop = &v9fs_dir_operations;
 324
 325		break;
 326	default:
 327		p9_debug(P9_DEBUG_ERROR, "BAD mode 0x%hx S_IFMT 0x%x\n",
 328			 mode, mode & S_IFMT);
 329		err = -EINVAL;
 330		goto error;
 331	}
 332error:
 333	return err;
 334
 335}
 336
 337/**
 338 * v9fs_evict_inode - Remove an inode from the inode cache
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 339 * @inode: inode to release
 340 *
 341 */
 342void v9fs_evict_inode(struct inode *inode)
 343{
 344	struct v9fs_inode __maybe_unused *v9inode = V9FS_I(inode);
 345	__le32 __maybe_unused version;
 346
 347	if (!is_bad_inode(inode)) {
 348		netfs_wait_for_outstanding_io(inode);
 349		truncate_inode_pages_final(&inode->i_data);
 350
 351		version = cpu_to_le32(v9inode->qid.version);
 352		netfs_clear_inode_writeback(inode, &version);
 353
 354		clear_inode(inode);
 355		filemap_fdatawrite(&inode->i_data);
 356
 357#ifdef CONFIG_9P_FSCACHE
 358		if (v9fs_inode_cookie(v9inode))
 359			fscache_relinquish_cookie(v9fs_inode_cookie(v9inode), false);
 360#endif
 361	} else
 362		clear_inode(inode);
 
 
 
 363}
 364
 365static int v9fs_test_inode(struct inode *inode, void *data)
 366{
 367	int umode;
 368	dev_t rdev;
 369	struct v9fs_inode *v9inode = V9FS_I(inode);
 370	struct p9_wstat *st = (struct p9_wstat *)data;
 371	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
 372
 373	umode = p9mode2unixmode(v9ses, st, &rdev);
 374	/* don't match inode of different type */
 375	if (inode_wrong_type(inode, umode))
 376		return 0;
 377
 378	/* compare qid details */
 379	if (memcmp(&v9inode->qid.version,
 380		   &st->qid.version, sizeof(v9inode->qid.version)))
 381		return 0;
 382
 383	if (v9inode->qid.type != st->qid.type)
 384		return 0;
 385
 386	if (v9inode->qid.path != st->qid.path)
 387		return 0;
 388	return 1;
 389}
 390
 391static int v9fs_test_new_inode(struct inode *inode, void *data)
 392{
 393	return 0;
 394}
 395
 396static int v9fs_set_inode(struct inode *inode,  void *data)
 397{
 398	struct v9fs_inode *v9inode = V9FS_I(inode);
 399	struct p9_wstat *st = (struct p9_wstat *)data;
 400
 401	memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
 402	return 0;
 403}
 404
 405static struct inode *v9fs_qid_iget(struct super_block *sb,
 406				   struct p9_qid *qid,
 407				   struct p9_wstat *st,
 408				   int new)
 409{
 410	dev_t rdev;
 411	int retval;
 412	umode_t umode;
 413	struct inode *inode;
 414	struct v9fs_session_info *v9ses = sb->s_fs_info;
 415	int (*test)(struct inode *inode, void *data);
 416
 417	if (new)
 418		test = v9fs_test_new_inode;
 419	else
 420		test = v9fs_test_inode;
 421
 422	inode = iget5_locked(sb, QID2INO(qid), test, v9fs_set_inode, st);
 
 423	if (!inode)
 424		return ERR_PTR(-ENOMEM);
 425	if (!(inode->i_state & I_NEW))
 426		return inode;
 427	/*
 428	 * initialize the inode with the stat info
 429	 * FIXME!! we may need support for stale inodes
 430	 * later.
 431	 */
 432	inode->i_ino = QID2INO(qid);
 433	umode = p9mode2unixmode(v9ses, st, &rdev);
 434	retval = v9fs_init_inode(v9ses, inode, umode, rdev);
 435	if (retval)
 436		goto error;
 437
 438	v9fs_stat2inode(st, inode, sb, 0);
 439	v9fs_set_netfs_context(inode);
 440	v9fs_cache_inode_get_cookie(inode);
 
 441	unlock_new_inode(inode);
 442	return inode;
 443error:
 444	iget_failed(inode);
 
 445	return ERR_PTR(retval);
 446
 447}
 448
 449struct inode *
 450v9fs_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
 451		    struct super_block *sb, int new)
 452{
 453	struct p9_wstat *st;
 454	struct inode *inode = NULL;
 455
 456	st = p9_client_stat(fid);
 457	if (IS_ERR(st))
 458		return ERR_CAST(st);
 459
 460	inode = v9fs_qid_iget(sb, &st->qid, st, new);
 461	p9stat_free(st);
 462	kfree(st);
 463	return inode;
 464}
 465
 466/**
 467 * v9fs_at_to_dotl_flags- convert Linux specific AT flags to
 468 * plan 9 AT flag.
 469 * @flags: flags to convert
 470 */
 471static int v9fs_at_to_dotl_flags(int flags)
 472{
 473	int rflags = 0;
 474
 475	if (flags & AT_REMOVEDIR)
 476		rflags |= P9_DOTL_AT_REMOVEDIR;
 477
 478	return rflags;
 479}
 480
 481/**
 482 * v9fs_dec_count - helper functon to drop i_nlink.
 483 *
 484 * If a directory had nlink <= 2 (including . and ..), then we should not drop
 485 * the link count, which indicates the underlying exported fs doesn't maintain
 486 * nlink accurately. e.g.
 487 * - overlayfs sets nlink to 1 for merged dir
 488 * - ext4 (with dir_nlink feature enabled) sets nlink to 1 if a dir has more
 489 *   than EXT4_LINK_MAX (65000) links.
 490 *
 491 * @inode: inode whose nlink is being dropped
 492 */
 493static void v9fs_dec_count(struct inode *inode)
 494{
 495	if (!S_ISDIR(inode->i_mode) || inode->i_nlink > 2)
 496		drop_nlink(inode);
 497}
 498
 499/**
 500 * v9fs_remove - helper function to remove files and directories
 501 * @dir: directory inode that is being deleted
 502 * @dentry:  dentry that is being deleted
 503 * @flags: removing a directory
 504 *
 505 */
 506
 507static int v9fs_remove(struct inode *dir, struct dentry *dentry, int flags)
 508{
 509	struct inode *inode;
 510	int retval = -EOPNOTSUPP;
 511	struct p9_fid *v9fid, *dfid;
 512	struct v9fs_session_info *v9ses;
 513
 514	p9_debug(P9_DEBUG_VFS, "inode: %p dentry: %p rmdir: %x\n",
 515		 dir, dentry, flags);
 516
 517	v9ses = v9fs_inode2v9ses(dir);
 518	inode = d_inode(dentry);
 519	dfid = v9fs_parent_fid(dentry);
 520	if (IS_ERR(dfid)) {
 521		retval = PTR_ERR(dfid);
 522		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", retval);
 523		return retval;
 524	}
 525	if (v9fs_proto_dotl(v9ses))
 526		retval = p9_client_unlinkat(dfid, dentry->d_name.name,
 527					    v9fs_at_to_dotl_flags(flags));
 528	p9_fid_put(dfid);
 529	if (retval == -EOPNOTSUPP) {
 530		/* Try the one based on path */
 531		v9fid = v9fs_fid_clone(dentry);
 532		if (IS_ERR(v9fid))
 533			return PTR_ERR(v9fid);
 534		retval = p9_client_remove(v9fid);
 535	}
 536	if (!retval) {
 537		/*
 538		 * directories on unlink should have zero
 539		 * link count
 540		 */
 541		if (flags & AT_REMOVEDIR) {
 542			clear_nlink(inode);
 543			v9fs_dec_count(dir);
 544		} else
 545			v9fs_dec_count(inode);
 546
 547		v9fs_invalidate_inode_attr(inode);
 548		v9fs_invalidate_inode_attr(dir);
 549
 550		/* invalidate all fids associated with dentry */
 551		/* NOTE: This will not include open fids */
 552		dentry->d_op->d_release(dentry);
 553	}
 554	return retval;
 555}
 556
 557/**
 558 * v9fs_create - Create a file
 559 * @v9ses: session information
 560 * @dir: directory that dentry is being created in
 561 * @dentry:  dentry that is being created
 562 * @extension: 9p2000.u extension string to support devices, etc.
 563 * @perm: create permissions
 564 * @mode: open mode
 565 *
 566 */
 567static struct p9_fid *
 568v9fs_create(struct v9fs_session_info *v9ses, struct inode *dir,
 569		struct dentry *dentry, char *extension, u32 perm, u8 mode)
 570{
 571	int err;
 572	const unsigned char *name;
 573	struct p9_fid *dfid, *ofid = NULL, *fid = NULL;
 574	struct inode *inode;
 575
 576	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
 577
 578	name = dentry->d_name.name;
 579	dfid = v9fs_parent_fid(dentry);
 
 
 
 580	if (IS_ERR(dfid)) {
 581		err = PTR_ERR(dfid);
 582		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
 583		return ERR_PTR(err);
 584	}
 585
 586	/* clone a fid to use for creation */
 587	ofid = clone_fid(dfid);
 588	if (IS_ERR(ofid)) {
 589		err = PTR_ERR(ofid);
 590		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
 591		goto error;
 592	}
 593
 594	err = p9_client_fcreate(ofid, name, perm, mode, extension);
 595	if (err < 0) {
 596		p9_debug(P9_DEBUG_VFS, "p9_client_fcreate failed %d\n", err);
 
 
 
 
 
 
 
 
 
 597		goto error;
 598	}
 599
 600	if (!(perm & P9_DMLINK)) {
 601		/* now walk from the parent so we can get unopened fid */
 602		fid = p9_client_walk(dfid, 1, &name, 1);
 603		if (IS_ERR(fid)) {
 604			err = PTR_ERR(fid);
 605			p9_debug(P9_DEBUG_VFS,
 606				   "p9_client_walk failed %d\n", err);
 607			goto error;
 608		}
 609		/*
 610		 * instantiate inode and assign the unopened fid to the dentry
 611		 */
 612		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 613		if (IS_ERR(inode)) {
 614			err = PTR_ERR(inode);
 615			p9_debug(P9_DEBUG_VFS,
 616				   "inode creation failed %d\n", err);
 617			goto error;
 618		}
 619		v9fs_fid_add(dentry, &fid);
 620		d_instantiate(dentry, inode);
 621	}
 622	p9_fid_put(dfid);
 
 
 
 623	return ofid;
 624error:
 625	p9_fid_put(dfid);
 626	p9_fid_put(ofid);
 627	p9_fid_put(fid);
 
 
 
 628	return ERR_PTR(err);
 629}
 630
 631/**
 632 * v9fs_vfs_create - VFS hook to create a regular file
 633 * @idmap: idmap of the mount
 634 * @dir: The parent directory
 635 * @dentry: The name of file to be created
 636 * @mode: The UNIX file mode to set
 637 * @excl: True if the file must not yet exist
 638 *
 639 * open(.., O_CREAT) is handled in v9fs_vfs_atomic_open().  This is only called
 640 * for mknod(2).
 641 *
 642 */
 643
 644static int
 645v9fs_vfs_create(struct mnt_idmap *idmap, struct inode *dir,
 646		struct dentry *dentry, umode_t mode, bool excl)
 647{
 648	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
 649	u32 perm = unixmode2p9mode(v9ses, mode);
 650	struct p9_fid *fid;
 
 
 
 
 
 
 
 
 
 
 
 
 
 651
 652	/* P9_OEXCL? */
 653	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_ORDWR);
 654	if (IS_ERR(fid))
 655		return PTR_ERR(fid);
 
 
 
 
 656
 657	v9fs_invalidate_inode_attr(dir);
 658	p9_fid_put(fid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 659
 660	return 0;
 
 
 
 
 
 
 661}
 662
 663/**
 664 * v9fs_vfs_mkdir - VFS mkdir hook to create a directory
 665 * @idmap: idmap of the mount
 666 * @dir:  inode that is being unlinked
 667 * @dentry: dentry that is being unlinked
 668 * @mode: mode for new directory
 669 *
 670 */
 671
 672static int v9fs_vfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
 673			  struct dentry *dentry, umode_t mode)
 674{
 675	int err;
 676	u32 perm;
 677	struct p9_fid *fid;
 678	struct v9fs_session_info *v9ses;
 679
 680	p9_debug(P9_DEBUG_VFS, "name %pd\n", dentry);
 681	err = 0;
 682	v9ses = v9fs_inode2v9ses(dir);
 683	perm = unixmode2p9mode(v9ses, mode | S_IFDIR);
 684	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, P9_OREAD);
 685	if (IS_ERR(fid)) {
 686		err = PTR_ERR(fid);
 687		fid = NULL;
 688	} else {
 689		inc_nlink(dir);
 690		v9fs_invalidate_inode_attr(dir);
 691	}
 692
 693	if (fid)
 694		p9_fid_put(fid);
 695
 696	return err;
 697}
 698
 699/**
 700 * v9fs_vfs_lookup - VFS lookup hook to "walk" to a new inode
 701 * @dir:  inode that is being walked from
 702 * @dentry: dentry that is being walked to?
 703 * @flags: lookup flags (unused)
 704 *
 705 */
 706
 707struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
 708				      unsigned int flags)
 709{
 710	struct dentry *res;
 
 711	struct v9fs_session_info *v9ses;
 712	struct p9_fid *dfid, *fid;
 713	struct inode *inode;
 714	const unsigned char *name;
 
 715
 716	p9_debug(P9_DEBUG_VFS, "dir: %p dentry: (%pd) %p flags: %x\n",
 717		 dir, dentry, dentry, flags);
 718
 719	if (dentry->d_name.len > NAME_MAX)
 720		return ERR_PTR(-ENAMETOOLONG);
 721
 
 722	v9ses = v9fs_inode2v9ses(dir);
 723	/* We can walk d_parent because we hold the dir->i_mutex */
 724	dfid = v9fs_parent_fid(dentry);
 725	if (IS_ERR(dfid))
 726		return ERR_CAST(dfid);
 727
 
 
 
 
 
 
 
 
 
 
 
 728	/*
 729	 * Make sure we don't use a wrong inode due to parallel
 730	 * unlink. For cached mode create calls request for new
 731	 * inode. But with cache disabled, lookup should do this.
 732	 */
 733	name = dentry->d_name.name;
 734	fid = p9_client_walk(dfid, 1, &name, 1);
 735	p9_fid_put(dfid);
 736	if (fid == ERR_PTR(-ENOENT))
 737		inode = NULL;
 738	else if (IS_ERR(fid))
 739		inode = ERR_CAST(fid);
 740	else if (v9ses->cache & (CACHE_META|CACHE_LOOSE))
 741		inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb);
 742	else
 743		inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
 
 
 
 
 
 
 
 
 
 744	/*
 745	 * If we had a rename on the server and a parallel lookup
 746	 * for the new name, then make sure we instantiate with
 747	 * the new name. ie look up for a/b, while on server somebody
 748	 * moved b under k and client parallely did a lookup for
 749	 * k/b.
 750	 */
 751	res = d_splice_alias(inode, dentry);
 752	if (!IS_ERR(fid)) {
 753		if (!res)
 754			v9fs_fid_add(dentry, &fid);
 755		else if (!IS_ERR(res))
 756			v9fs_fid_add(res, &fid);
 757		else
 758			p9_fid_put(fid);
 759	}
 760	return res;
 761}
 762
 763static int
 764v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
 765		     struct file *file, unsigned int flags, umode_t mode)
 766{
 767	int err;
 768	u32 perm;
 769	struct v9fs_inode __maybe_unused *v9inode;
 770	struct v9fs_session_info *v9ses;
 771	struct p9_fid *fid;
 772	struct dentry *res = NULL;
 773	struct inode *inode;
 774	int p9_omode;
 775
 776	if (d_in_lookup(dentry)) {
 777		res = v9fs_vfs_lookup(dir, dentry, 0);
 778		if (IS_ERR(res))
 779			return PTR_ERR(res);
 780
 781		if (res)
 782			dentry = res;
 783	}
 784
 785	/* Only creates */
 786	if (!(flags & O_CREAT) || d_really_is_positive(dentry))
 787		return finish_no_open(file, res);
 788
 789	v9ses = v9fs_inode2v9ses(dir);
 790	perm = unixmode2p9mode(v9ses, mode);
 791	p9_omode = v9fs_uflags2omode(flags, v9fs_proto_dotu(v9ses));
 792
 793	if ((v9ses->cache & CACHE_WRITEBACK) && (p9_omode & P9_OWRITE)) {
 794		p9_omode = (p9_omode & ~P9_OWRITE) | P9_ORDWR;
 795		p9_debug(P9_DEBUG_CACHE,
 796			"write-only file with writeback enabled, creating w/ O_RDWR\n");
 797	}
 798	fid = v9fs_create(v9ses, dir, dentry, NULL, perm, p9_omode);
 799	if (IS_ERR(fid)) {
 800		err = PTR_ERR(fid);
 801		goto error;
 802	}
 803
 804	v9fs_invalidate_inode_attr(dir);
 805	inode = d_inode(dentry);
 806	v9inode = V9FS_I(inode);
 807	err = finish_open(file, dentry, generic_file_open);
 808	if (err)
 809		goto error;
 810
 811	file->private_data = fid;
 812#ifdef CONFIG_9P_FSCACHE
 813	if (v9ses->cache & CACHE_FSCACHE)
 814		fscache_use_cookie(v9fs_inode_cookie(v9inode),
 815				   file->f_mode & FMODE_WRITE);
 816#endif
 817
 818	v9fs_fid_add_modes(fid, v9ses->flags, v9ses->cache, file->f_flags);
 819	v9fs_open_fid_add(inode, &fid);
 820
 821	file->f_mode |= FMODE_CREATED;
 822out:
 823	dput(res);
 824	return err;
 825
 826error:
 827	p9_fid_put(fid);
 828	goto out;
 829}
 830
 831/**
 832 * v9fs_vfs_unlink - VFS unlink hook to delete an inode
 833 * @i:  inode that is being unlinked
 834 * @d: dentry that is being unlinked
 835 *
 836 */
 837
 838int v9fs_vfs_unlink(struct inode *i, struct dentry *d)
 839{
 840	return v9fs_remove(i, d, 0);
 841}
 842
 843/**
 844 * v9fs_vfs_rmdir - VFS unlink hook to delete a directory
 845 * @i:  inode that is being unlinked
 846 * @d: dentry that is being unlinked
 847 *
 848 */
 849
 850int v9fs_vfs_rmdir(struct inode *i, struct dentry *d)
 851{
 852	return v9fs_remove(i, d, AT_REMOVEDIR);
 853}
 854
 855/**
 856 * v9fs_vfs_rename - VFS hook to rename an inode
 857 * @idmap: The idmap of the mount
 858 * @old_dir:  old dir inode
 859 * @old_dentry: old dentry
 860 * @new_dir: new dir inode
 861 * @new_dentry: new dentry
 862 * @flags: RENAME_* flags
 863 *
 864 */
 865
 866int
 867v9fs_vfs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
 868		struct dentry *old_dentry, struct inode *new_dir,
 869		struct dentry *new_dentry, unsigned int flags)
 870{
 871	int retval;
 872	struct inode *old_inode;
 873	struct inode *new_inode;
 874	struct v9fs_session_info *v9ses;
 875	struct p9_fid *oldfid = NULL, *dfid = NULL;
 876	struct p9_fid *olddirfid = NULL;
 877	struct p9_fid *newdirfid = NULL;
 878	struct p9_wstat wstat;
 879
 880	if (flags)
 881		return -EINVAL;
 882
 883	p9_debug(P9_DEBUG_VFS, "\n");
 884	old_inode = d_inode(old_dentry);
 885	new_inode = d_inode(new_dentry);
 886	v9ses = v9fs_inode2v9ses(old_inode);
 887	oldfid = v9fs_fid_lookup(old_dentry);
 888	if (IS_ERR(oldfid))
 889		return PTR_ERR(oldfid);
 890
 891	dfid = v9fs_parent_fid(old_dentry);
 892	olddirfid = clone_fid(dfid);
 893	p9_fid_put(dfid);
 894	dfid = NULL;
 895
 896	if (IS_ERR(olddirfid)) {
 897		retval = PTR_ERR(olddirfid);
 898		goto error;
 899	}
 900
 901	dfid = v9fs_parent_fid(new_dentry);
 902	newdirfid = clone_fid(dfid);
 903	p9_fid_put(dfid);
 904	dfid = NULL;
 905
 906	if (IS_ERR(newdirfid)) {
 907		retval = PTR_ERR(newdirfid);
 908		goto error;
 909	}
 910
 911	down_write(&v9ses->rename_sem);
 912	if (v9fs_proto_dotl(v9ses)) {
 913		retval = p9_client_renameat(olddirfid, old_dentry->d_name.name,
 914					    newdirfid, new_dentry->d_name.name);
 915		if (retval == -EOPNOTSUPP)
 916			retval = p9_client_rename(oldfid, newdirfid,
 917						  new_dentry->d_name.name);
 918		if (retval != -EOPNOTSUPP)
 919			goto error_locked;
 920	}
 921	if (old_dentry->d_parent != new_dentry->d_parent) {
 922		/*
 923		 * 9P .u can only handle file rename in the same directory
 924		 */
 925
 926		p9_debug(P9_DEBUG_ERROR, "old dir and new dir are different\n");
 
 927		retval = -EXDEV;
 928		goto error_locked;
 929	}
 930	v9fs_blank_wstat(&wstat);
 931	wstat.muid = v9ses->uname;
 932	wstat.name = new_dentry->d_name.name;
 933	retval = p9_client_wstat(oldfid, &wstat);
 934
 935error_locked:
 936	if (!retval) {
 937		if (new_inode) {
 938			if (S_ISDIR(new_inode->i_mode))
 939				clear_nlink(new_inode);
 940			else
 941				v9fs_dec_count(new_inode);
 942		}
 943		if (S_ISDIR(old_inode->i_mode)) {
 944			if (!new_inode)
 945				inc_nlink(new_dir);
 946			v9fs_dec_count(old_dir);
 947		}
 948		v9fs_invalidate_inode_attr(old_inode);
 949		v9fs_invalidate_inode_attr(old_dir);
 950		v9fs_invalidate_inode_attr(new_dir);
 951
 952		/* successful rename */
 953		d_move(old_dentry, new_dentry);
 954	}
 955	up_write(&v9ses->rename_sem);
 
 956
 957error:
 958	p9_fid_put(newdirfid);
 959	p9_fid_put(olddirfid);
 960	p9_fid_put(oldfid);
 961	return retval;
 962}
 963
 964/**
 965 * v9fs_vfs_getattr - retrieve file metadata
 966 * @idmap: idmap of the mount
 967 * @path: Object to query
 968 * @stat: metadata structure to populate
 969 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
 970 * @flags: AT_STATX_xxx setting
 971 *
 972 */
 973
 974static int
 975v9fs_vfs_getattr(struct mnt_idmap *idmap, const struct path *path,
 976		 struct kstat *stat, u32 request_mask, unsigned int flags)
 977{
 978	struct dentry *dentry = path->dentry;
 979	struct inode *inode = d_inode(dentry);
 980	struct v9fs_session_info *v9ses;
 981	struct p9_fid *fid;
 982	struct p9_wstat *st;
 983
 984	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 
 985	v9ses = v9fs_dentry2v9ses(dentry);
 986	if (v9ses->cache & (CACHE_META|CACHE_LOOSE)) {
 987		generic_fillattr(&nop_mnt_idmap, request_mask, inode, stat);
 988		return 0;
 989	} else if (v9ses->cache & CACHE_WRITEBACK) {
 990		if (S_ISREG(inode->i_mode)) {
 991			int retval = filemap_fdatawrite(inode->i_mapping);
 992
 993			if (retval)
 994				p9_debug(P9_DEBUG_ERROR,
 995				    "flushing writeback during getattr returned %d\n", retval);
 996		}
 997	}
 998	fid = v9fs_fid_lookup(dentry);
 999	if (IS_ERR(fid))
1000		return PTR_ERR(fid);
1001
1002	st = p9_client_stat(fid);
1003	p9_fid_put(fid);
1004	if (IS_ERR(st))
1005		return PTR_ERR(st);
1006
1007	v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
1008	generic_fillattr(&nop_mnt_idmap, request_mask, d_inode(dentry), stat);
1009
1010	p9stat_free(st);
1011	kfree(st);
1012	return 0;
1013}
1014
1015/**
1016 * v9fs_vfs_setattr - set file metadata
1017 * @idmap: idmap of the mount
1018 * @dentry: file whose metadata to set
1019 * @iattr: metadata assignment structure
1020 *
1021 */
1022
1023static int v9fs_vfs_setattr(struct mnt_idmap *idmap,
1024			    struct dentry *dentry, struct iattr *iattr)
1025{
1026	int retval, use_dentry = 0;
1027	struct inode *inode = d_inode(dentry);
1028	struct v9fs_session_info *v9ses;
1029	struct p9_fid *fid = NULL;
1030	struct p9_wstat wstat;
1031
1032	p9_debug(P9_DEBUG_VFS, "\n");
1033	retval = setattr_prepare(&nop_mnt_idmap, dentry, iattr);
1034	if (retval)
1035		return retval;
1036
 
1037	v9ses = v9fs_dentry2v9ses(dentry);
1038	if (iattr->ia_valid & ATTR_FILE) {
1039		fid = iattr->ia_file->private_data;
1040		WARN_ON(!fid);
1041	}
1042	if (!fid) {
1043		fid = v9fs_fid_lookup(dentry);
1044		use_dentry = 1;
1045	}
1046	if (IS_ERR(fid))
1047		return PTR_ERR(fid);
1048
1049	v9fs_blank_wstat(&wstat);
1050	if (iattr->ia_valid & ATTR_MODE)
1051		wstat.mode = unixmode2p9mode(v9ses, iattr->ia_mode);
1052
1053	if (iattr->ia_valid & ATTR_MTIME)
1054		wstat.mtime = iattr->ia_mtime.tv_sec;
1055
1056	if (iattr->ia_valid & ATTR_ATIME)
1057		wstat.atime = iattr->ia_atime.tv_sec;
1058
1059	if (iattr->ia_valid & ATTR_SIZE)
1060		wstat.length = iattr->ia_size;
1061
1062	if (v9fs_proto_dotu(v9ses)) {
1063		if (iattr->ia_valid & ATTR_UID)
1064			wstat.n_uid = iattr->ia_uid;
1065
1066		if (iattr->ia_valid & ATTR_GID)
1067			wstat.n_gid = iattr->ia_gid;
1068	}
1069
1070	/* Write all dirty data */
1071	if (d_is_reg(dentry)) {
1072		retval = filemap_fdatawrite(inode->i_mapping);
1073		if (retval)
1074			p9_debug(P9_DEBUG_ERROR,
1075			    "flushing writeback during setattr returned %d\n", retval);
1076	}
1077
1078	retval = p9_client_wstat(fid, &wstat);
1079
1080	if (use_dentry)
1081		p9_fid_put(fid);
1082
1083	if (retval < 0)
1084		return retval;
1085
1086	if ((iattr->ia_valid & ATTR_SIZE) &&
1087		 iattr->ia_size != i_size_read(inode)) {
1088		truncate_setsize(inode, iattr->ia_size);
1089		netfs_resize_file(netfs_inode(inode), iattr->ia_size, true);
1090
1091#ifdef CONFIG_9P_FSCACHE
1092		if (v9ses->cache & CACHE_FSCACHE) {
1093			struct v9fs_inode *v9inode = V9FS_I(inode);
1094
1095			fscache_resize_cookie(v9fs_inode_cookie(v9inode), iattr->ia_size);
1096		}
1097#endif
1098	}
1099
1100	v9fs_invalidate_inode_attr(inode);
1101
1102	setattr_copy(&nop_mnt_idmap, inode, iattr);
1103	mark_inode_dirty(inode);
1104	return 0;
1105}
1106
1107/**
1108 * v9fs_stat2inode - populate an inode structure with mistat info
1109 * @stat: Plan 9 metadata (mistat) structure
1110 * @inode: inode to populate
1111 * @sb: superblock of filesystem
1112 * @flags: control flags (e.g. V9FS_STAT2INODE_KEEP_ISIZE)
1113 *
1114 */
1115
1116void
1117v9fs_stat2inode(struct p9_wstat *stat, struct inode *inode,
1118		 struct super_block *sb, unsigned int flags)
1119{
1120	umode_t mode;
 
 
 
1121	struct v9fs_session_info *v9ses = sb->s_fs_info;
1122	struct v9fs_inode *v9inode = V9FS_I(inode);
1123
1124	inode_set_atime(inode, stat->atime, 0);
1125	inode_set_mtime(inode, stat->mtime, 0);
1126	inode_set_ctime(inode, stat->mtime, 0);
 
 
1127
1128	inode->i_uid = v9ses->dfltuid;
1129	inode->i_gid = v9ses->dfltgid;
1130
1131	if (v9fs_proto_dotu(v9ses)) {
1132		inode->i_uid = stat->n_uid;
1133		inode->i_gid = stat->n_gid;
1134	}
1135	if ((S_ISREG(inode->i_mode)) || (S_ISDIR(inode->i_mode))) {
1136		if (v9fs_proto_dotu(v9ses)) {
1137			unsigned int i_nlink;
1138			/*
1139			 * Hadlink support got added later to the .u extension.
1140			 * So there can be a server out there that doesn't
1141			 * support this even with .u extension. That would
1142			 * just leave us with stat->extension being an empty
1143			 * string, though.
1144			 */
 
1145			/* HARDLINKCOUNT %u */
1146			if (sscanf(stat->extension,
1147				   " HARDLINKCOUNT %u", &i_nlink) == 1)
1148				set_nlink(inode, i_nlink);
1149		}
1150	}
1151	mode = p9mode2perm(v9ses, stat);
1152	mode |= inode->i_mode & ~S_IALLUGO;
1153	inode->i_mode = mode;
 
1154
1155	v9inode->netfs.remote_i_size = stat->length;
1156	if (!(flags & V9FS_STAT2INODE_KEEP_ISIZE))
1157		v9fs_i_size_write(inode, stat->length);
1158	/* not real number of blocks, but 512 byte ones ... */
1159	inode->i_blocks = (stat->length + 512 - 1) >> 9;
1160	v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
1161}
1162
1163/**
1164 * v9fs_vfs_get_link - follow a symlink path
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1165 * @dentry: dentry for symlink
1166 * @inode: inode for symlink
1167 * @done: delayed call for when we are done with the return value
 
1168 */
1169
1170static const char *v9fs_vfs_get_link(struct dentry *dentry,
1171				     struct inode *inode,
1172				     struct delayed_call *done)
1173{
 
 
1174	struct v9fs_session_info *v9ses;
1175	struct p9_fid *fid;
1176	struct p9_wstat *st;
1177	char *res;
1178
1179	if (!dentry)
1180		return ERR_PTR(-ECHILD);
1181
 
 
1182	v9ses = v9fs_dentry2v9ses(dentry);
1183	if (!v9fs_proto_dotu(v9ses))
1184		return ERR_PTR(-EBADF);
1185
1186	p9_debug(P9_DEBUG_VFS, "%pd\n", dentry);
1187	fid = v9fs_fid_lookup(dentry);
 
 
1188
1189	if (IS_ERR(fid))
1190		return ERR_CAST(fid);
1191
1192	st = p9_client_stat(fid);
1193	p9_fid_put(fid);
1194	if (IS_ERR(st))
1195		return ERR_CAST(st);
1196
1197	if (!(st->mode & P9_DMSYMLINK)) {
1198		p9stat_free(st);
1199		kfree(st);
1200		return ERR_PTR(-EINVAL);
1201	}
1202	res = st->extension;
1203	st->extension = NULL;
1204	if (strlen(res) >= PATH_MAX)
1205		res[PATH_MAX - 1] = '\0';
1206
 
 
 
 
 
1207	p9stat_free(st);
1208	kfree(st);
1209	set_delayed_call(done, kfree_link, res);
1210	return res;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1211}
1212
1213/**
1214 * v9fs_vfs_mkspecial - create a special file
1215 * @dir: inode to create special file in
1216 * @dentry: dentry to create
1217 * @perm: mode to create special file
1218 * @extension: 9p2000.u format extension string representing special file
1219 *
1220 */
1221
1222static int v9fs_vfs_mkspecial(struct inode *dir, struct dentry *dentry,
1223	u32 perm, const char *extension)
1224{
 
1225	struct p9_fid *fid;
1226	struct v9fs_session_info *v9ses;
1227
1228	v9ses = v9fs_inode2v9ses(dir);
1229	if (!v9fs_proto_dotu(v9ses)) {
1230		p9_debug(P9_DEBUG_ERROR, "not extended\n");
1231		return -EPERM;
1232	}
1233
 
1234	fid = v9fs_create(v9ses, dir, dentry, (char *) extension, perm,
1235								P9_OREAD);
1236	if (IS_ERR(fid))
1237		return PTR_ERR(fid);
1238
1239	v9fs_invalidate_inode_attr(dir);
1240	p9_fid_put(fid);
1241	return 0;
1242}
1243
1244/**
1245 * v9fs_vfs_symlink - helper function to create symlinks
1246 * @idmap: idmap of the mount
1247 * @dir: directory inode containing symlink
1248 * @dentry: dentry for symlink
1249 * @symname: symlink data
1250 *
1251 * See Also: 9P2000.u RFC for more information
1252 *
1253 */
1254
1255static int
1256v9fs_vfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
1257		 struct dentry *dentry, const char *symname)
1258{
1259	p9_debug(P9_DEBUG_VFS, " %lu,%pd,%s\n",
1260		 dir->i_ino, dentry, symname);
1261
1262	return v9fs_vfs_mkspecial(dir, dentry, P9_DMSYMLINK, symname);
1263}
1264
1265#define U32_MAX_DIGITS 10
1266
1267/**
1268 * v9fs_vfs_link - create a hardlink
1269 * @old_dentry: dentry for file to link to
1270 * @dir: inode destination for new link
1271 * @dentry: dentry for link
1272 *
1273 */
1274
1275static int
1276v9fs_vfs_link(struct dentry *old_dentry, struct inode *dir,
1277	      struct dentry *dentry)
1278{
1279	int retval;
1280	char name[1 + U32_MAX_DIGITS + 2]; /* sign + number + \n + \0 */
1281	struct p9_fid *oldfid;
1282
1283	p9_debug(P9_DEBUG_VFS, " %lu,%pd,%pd\n",
1284		 dir->i_ino, dentry, old_dentry);
 
1285
1286	oldfid = v9fs_fid_clone(old_dentry);
1287	if (IS_ERR(oldfid))
1288		return PTR_ERR(oldfid);
1289
 
 
 
 
 
 
1290	sprintf(name, "%d\n", oldfid->fid);
1291	retval = v9fs_vfs_mkspecial(dir, dentry, P9_DMLINK, name);
 
1292	if (!retval) {
1293		v9fs_refresh_inode(oldfid, d_inode(old_dentry));
1294		v9fs_invalidate_inode_attr(dir);
1295	}
1296	p9_fid_put(oldfid);
 
1297	return retval;
1298}
1299
1300/**
1301 * v9fs_vfs_mknod - create a special file
1302 * @idmap: idmap of the mount
1303 * @dir: inode destination for new link
1304 * @dentry: dentry for file
1305 * @mode: mode for creation
1306 * @rdev: device associated with special file
1307 *
1308 */
1309
1310static int
1311v9fs_vfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
1312	       struct dentry *dentry, umode_t mode, dev_t rdev)
1313{
1314	struct v9fs_session_info *v9ses = v9fs_inode2v9ses(dir);
1315	int retval;
1316	char name[2 + U32_MAX_DIGITS + 1 + U32_MAX_DIGITS + 1];
1317	u32 perm;
1318
1319	p9_debug(P9_DEBUG_VFS, " %lu,%pd mode: %x MAJOR: %u MINOR: %u\n",
1320		 dir->i_ino, dentry, mode,
1321		 MAJOR(rdev), MINOR(rdev));
1322
 
 
 
 
 
 
1323	/* build extension */
1324	if (S_ISBLK(mode))
1325		sprintf(name, "b %u %u", MAJOR(rdev), MINOR(rdev));
1326	else if (S_ISCHR(mode))
1327		sprintf(name, "c %u %u", MAJOR(rdev), MINOR(rdev));
1328	else
 
 
1329		*name = 0;
 
 
 
 
1330
1331	perm = unixmode2p9mode(v9ses, mode);
1332	retval = v9fs_vfs_mkspecial(dir, dentry, perm, name);
1333
1334	return retval;
1335}
1336
1337int v9fs_refresh_inode(struct p9_fid *fid, struct inode *inode)
1338{
1339	int umode;
1340	dev_t rdev;
 
1341	struct p9_wstat *st;
1342	struct v9fs_session_info *v9ses;
1343	unsigned int flags;
1344
1345	v9ses = v9fs_inode2v9ses(inode);
1346	st = p9_client_stat(fid);
1347	if (IS_ERR(st))
1348		return PTR_ERR(st);
1349	/*
1350	 * Don't update inode if the file type is different
1351	 */
1352	umode = p9mode2unixmode(v9ses, st, &rdev);
1353	if (inode_wrong_type(inode, umode))
1354		goto out;
1355
 
1356	/*
1357	 * We don't want to refresh inode->i_size,
1358	 * because we may have cached data
1359	 */
1360	flags = (v9ses->cache & CACHE_LOOSE) ?
1361		V9FS_STAT2INODE_KEEP_ISIZE : 0;
1362	v9fs_stat2inode(st, inode, inode->i_sb, flags);
 
 
1363out:
1364	p9stat_free(st);
1365	kfree(st);
1366	return 0;
1367}
1368
1369static const struct inode_operations v9fs_dir_inode_operations_dotu = {
1370	.create = v9fs_vfs_create,
1371	.lookup = v9fs_vfs_lookup,
1372	.atomic_open = v9fs_vfs_atomic_open,
1373	.symlink = v9fs_vfs_symlink,
1374	.link = v9fs_vfs_link,
1375	.unlink = v9fs_vfs_unlink,
1376	.mkdir = v9fs_vfs_mkdir,
1377	.rmdir = v9fs_vfs_rmdir,
1378	.mknod = v9fs_vfs_mknod,
1379	.rename = v9fs_vfs_rename,
1380	.getattr = v9fs_vfs_getattr,
1381	.setattr = v9fs_vfs_setattr,
1382};
1383
1384static const struct inode_operations v9fs_dir_inode_operations = {
1385	.create = v9fs_vfs_create,
1386	.lookup = v9fs_vfs_lookup,
1387	.atomic_open = v9fs_vfs_atomic_open,
1388	.unlink = v9fs_vfs_unlink,
1389	.mkdir = v9fs_vfs_mkdir,
1390	.rmdir = v9fs_vfs_rmdir,
1391	.mknod = v9fs_vfs_mknod,
1392	.rename = v9fs_vfs_rename,
1393	.getattr = v9fs_vfs_getattr,
1394	.setattr = v9fs_vfs_setattr,
1395};
1396
1397static const struct inode_operations v9fs_file_inode_operations = {
1398	.getattr = v9fs_vfs_getattr,
1399	.setattr = v9fs_vfs_setattr,
1400};
1401
1402static const struct inode_operations v9fs_symlink_inode_operations = {
1403	.get_link = v9fs_vfs_get_link,
 
 
1404	.getattr = v9fs_vfs_getattr,
1405	.setattr = v9fs_vfs_setattr,
1406};
1407