1// SPDX-License-Identifier: GPL-2.0-or-later
   2/* dir.c: AFS filesystem directory handling
   3 *
   4 * Copyright (C) 2002, 2018 Red Hat, Inc. All Rights Reserved.
   5 * Written by David Howells (dhowells@redhat.com)
   6 */
   7
   8#include <linux/kernel.h>
   9#include <linux/fs.h>
  10#include <linux/namei.h>
  11#include <linux/pagemap.h>
  12#include <linux/swap.h>
  13#include <linux/ctype.h>
  14#include <linux/sched.h>
  15#include <linux/iversion.h>
  16#include <linux/task_io_accounting_ops.h>
  17#include "internal.h"
  18#include "afs_fs.h"
  19#include "xdr_fs.h"
  20
  21static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
  22				 unsigned int flags);
  23static int afs_dir_open(struct inode *inode, struct file *file);
  24static int afs_readdir(struct file *file, struct dir_context *ctx);
  25static int afs_d_revalidate(struct dentry *dentry, unsigned int flags);
  26static int afs_d_delete(const struct dentry *dentry);
  27static void afs_d_iput(struct dentry *dentry, struct inode *inode);
  28static bool afs_lookup_one_filldir(struct dir_context *ctx, const char *name, int nlen,
  29				  loff_t fpos, u64 ino, unsigned dtype);
  30static bool afs_lookup_filldir(struct dir_context *ctx, const char *name, int nlen,
  31			      loff_t fpos, u64 ino, unsigned dtype);
  32static int afs_create(struct mnt_idmap *idmap, struct inode *dir,
  33		      struct dentry *dentry, umode_t mode, bool excl);
  34static int afs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
  35		     struct dentry *dentry, umode_t mode);
  36static int afs_rmdir(struct inode *dir, struct dentry *dentry);
  37static int afs_unlink(struct inode *dir, struct dentry *dentry);
  38static int afs_link(struct dentry *from, struct inode *dir,
  39		    struct dentry *dentry);
  40static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
  41		       struct dentry *dentry, const char *content);
  42static int afs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
  43		      struct dentry *old_dentry, struct inode *new_dir,
  44		      struct dentry *new_dentry, unsigned int flags);
  45static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags);
  46static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
  47				   size_t length);
  48
  49static bool afs_dir_dirty_folio(struct address_space *mapping,
  50		struct folio *folio)
  51{
  52	BUG(); /* This should never happen. */
  53}
  54
  55const struct file_operations afs_dir_file_operations = {
  56	.open		= afs_dir_open,
  57	.release	= afs_release,
  58	.iterate_shared	= afs_readdir,
  59	.lock		= afs_lock,
  60	.llseek		= generic_file_llseek,
  61};
  62
  63const struct inode_operations afs_dir_inode_operations = {
  64	.create		= afs_create,
  65	.lookup		= afs_lookup,
  66	.link		= afs_link,
  67	.unlink		= afs_unlink,
  68	.symlink	= afs_symlink,
  69	.mkdir		= afs_mkdir,
  70	.rmdir		= afs_rmdir,
  71	.rename		= afs_rename,
  72	.permission	= afs_permission,
  73	.getattr	= afs_getattr,
  74	.setattr	= afs_setattr,
  75};
  76
  77const struct address_space_operations afs_dir_aops = {
  78	.dirty_folio	= afs_dir_dirty_folio,
  79	.release_folio	= afs_dir_release_folio,
  80	.invalidate_folio = afs_dir_invalidate_folio,
  81	.migrate_folio	= filemap_migrate_folio,
  82};
  83
  84const struct dentry_operations afs_fs_dentry_operations = {
  85	.d_revalidate	= afs_d_revalidate,
  86	.d_delete	= afs_d_delete,
  87	.d_release	= afs_d_release,
  88	.d_automount	= afs_d_automount,
  89	.d_iput		= afs_d_iput,
  90};
  91
  92struct afs_lookup_one_cookie {
  93	struct dir_context	ctx;
  94	struct qstr		name;
  95	bool			found;
  96	struct afs_fid		fid;
  97};
  98
  99struct afs_lookup_cookie {
 100	struct dir_context	ctx;
 101	struct qstr		name;
 102	bool			found;
 103	bool			one_only;
 104	unsigned short		nr_fids;
 105	struct afs_fid		fids[50];
 106};
 107
 108/*
 109 * Drop the refs that we're holding on the folios we were reading into.  We've
 110 * got refs on the first nr_pages pages.
 111 */
 112static void afs_dir_read_cleanup(struct afs_read *req)
 113{
 114	struct address_space *mapping = req->vnode->netfs.inode.i_mapping;
 115	struct folio *folio;
 116	pgoff_t last = req->nr_pages - 1;
 117
 118	XA_STATE(xas, &mapping->i_pages, 0);
 119
 120	if (unlikely(!req->nr_pages))
 121		return;
 122
 123	rcu_read_lock();
 124	xas_for_each(&xas, folio, last) {
 125		if (xas_retry(&xas, folio))
 126			continue;
 127		BUG_ON(xa_is_value(folio));
 128		ASSERTCMP(folio->mapping, ==, mapping);
 129
 130		folio_put(folio);
 131	}
 132
 133	rcu_read_unlock();
 134}
 135
 136/*
 137 * check that a directory folio is valid
 138 */
 139static bool afs_dir_check_folio(struct afs_vnode *dvnode, struct folio *folio,
 140				loff_t i_size)
 141{
 142	union afs_xdr_dir_block *block;
 143	size_t offset, size;
 144	loff_t pos;
 145
 146	/* Determine how many magic numbers there should be in this folio, but
 147	 * we must take care because the directory may change size under us.
 148	 */
 149	pos = folio_pos(folio);
 150	if (i_size <= pos)
 151		goto checked;
 152
 153	size = min_t(loff_t, folio_size(folio), i_size - pos);
 154	for (offset = 0; offset < size; offset += sizeof(*block)) {
 155		block = kmap_local_folio(folio, offset);
 156		if (block->hdr.magic != AFS_DIR_MAGIC) {
 157			printk("kAFS: %s(%lx): [%llx] bad magic %zx/%zx is %04hx\n",
 158			       __func__, dvnode->netfs.inode.i_ino,
 159			       pos, offset, size, ntohs(block->hdr.magic));
 160			trace_afs_dir_check_failed(dvnode, pos + offset, i_size);
 161			kunmap_local(block);
 162			trace_afs_file_error(dvnode, -EIO, afs_file_error_dir_bad_magic);
 163			goto error;
 164		}
 165
 166		/* Make sure each block is NUL terminated so we can reasonably
 167		 * use string functions on it.  The filenames in the folio
 168		 * *should* be NUL-terminated anyway.
 169		 */
 170		((u8 *)block)[AFS_DIR_BLOCK_SIZE - 1] = 0;
 171
 172		kunmap_local(block);
 173	}
 174checked:
 175	afs_stat_v(dvnode, n_read_dir);
 176	return true;
 177
 178error:
 179	return false;
 180}
 181
 182/*
 183 * Dump the contents of a directory.
 184 */
 185static void afs_dir_dump(struct afs_vnode *dvnode, struct afs_read *req)
 186{
 187	union afs_xdr_dir_block *block;
 188	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
 189	struct folio *folio;
 190	pgoff_t last = req->nr_pages - 1;
 191	size_t offset, size;
 192
 193	XA_STATE(xas, &mapping->i_pages, 0);
 194
 195	pr_warn("DIR %llx:%llx f=%llx l=%llx al=%llx\n",
 196		dvnode->fid.vid, dvnode->fid.vnode,
 197		req->file_size, req->len, req->actual_len);
 198	pr_warn("DIR %llx %x %zx %zx\n",
 199		req->pos, req->nr_pages,
 200		req->iter->iov_offset,  iov_iter_count(req->iter));
 201
 202	xas_for_each(&xas, folio, last) {
 203		if (xas_retry(&xas, folio))
 204			continue;
 205
 206		BUG_ON(folio->mapping != mapping);
 207
 208		size = min_t(loff_t, folio_size(folio), req->actual_len - folio_pos(folio));
 209		for (offset = 0; offset < size; offset += sizeof(*block)) {
 210			block = kmap_local_folio(folio, offset);
 211			pr_warn("[%02lx] %32phN\n", folio->index + offset, block);
 212			kunmap_local(block);
 213		}
 214	}
 215}
 216
 217/*
 218 * Check all the blocks in a directory.  All the folios are held pinned.
 219 */
 220static int afs_dir_check(struct afs_vnode *dvnode, struct afs_read *req)
 221{
 222	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
 223	struct folio *folio;
 224	pgoff_t last = req->nr_pages - 1;
 225	int ret = 0;
 226
 227	XA_STATE(xas, &mapping->i_pages, 0);
 228
 229	if (unlikely(!req->nr_pages))
 230		return 0;
 231
 232	rcu_read_lock();
 233	xas_for_each(&xas, folio, last) {
 234		if (xas_retry(&xas, folio))
 235			continue;
 236
 237		BUG_ON(folio->mapping != mapping);
 238
 239		if (!afs_dir_check_folio(dvnode, folio, req->actual_len)) {
 240			afs_dir_dump(dvnode, req);
 241			ret = -EIO;
 242			break;
 243		}
 244	}
 245
 246	rcu_read_unlock();
 247	return ret;
 248}
 249
 250/*
 251 * open an AFS directory file
 252 */
 253static int afs_dir_open(struct inode *inode, struct file *file)
 254{
 255	_enter("{%lu}", inode->i_ino);
 256
 257	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 258	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 259
 260	if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(inode)->flags))
 261		return -ENOENT;
 262
 263	return afs_open(inode, file);
 264}
 265
 266/*
 267 * Read the directory into the pagecache in one go, scrubbing the previous
 268 * contents.  The list of folios is returned, pinning them so that they don't
 269 * get reclaimed during the iteration.
 270 */
 271static struct afs_read *afs_read_dir(struct afs_vnode *dvnode, struct key *key)
 272	__acquires(&dvnode->validate_lock)
 273{
 274	struct address_space *mapping = dvnode->netfs.inode.i_mapping;
 275	struct afs_read *req;
 276	loff_t i_size;
 277	int nr_pages, i;
 278	int ret;
 279	loff_t remote_size = 0;
 280
 281	_enter("");
 282
 283	req = kzalloc(sizeof(*req), GFP_KERNEL);
 284	if (!req)
 285		return ERR_PTR(-ENOMEM);
 286
 287	refcount_set(&req->usage, 1);
 288	req->vnode = dvnode;
 289	req->key = key_get(key);
 290	req->cleanup = afs_dir_read_cleanup;
 291
 292expand:
 293	i_size = i_size_read(&dvnode->netfs.inode);
 294	if (i_size < remote_size)
 295	    i_size = remote_size;
 296	if (i_size < 2048) {
 297		ret = afs_bad(dvnode, afs_file_error_dir_small);
 298		goto error;
 299	}
 300	if (i_size > 2048 * 1024) {
 301		trace_afs_file_error(dvnode, -EFBIG, afs_file_error_dir_big);
 302		ret = -EFBIG;
 303		goto error;
 304	}
 305
 306	_enter("%llu", i_size);
 307
 308	nr_pages = (i_size + PAGE_SIZE - 1) / PAGE_SIZE;
 309
 310	req->actual_len = i_size; /* May change */
 311	req->len = nr_pages * PAGE_SIZE; /* We can ask for more than there is */
 312	req->data_version = dvnode->status.data_version; /* May change */
 313	iov_iter_xarray(&req->def_iter, ITER_DEST, &dvnode->netfs.inode.i_mapping->i_pages,
 314			0, i_size);
 315	req->iter = &req->def_iter;
 316
 317	/* Fill in any gaps that we might find where the memory reclaimer has
 318	 * been at work and pin all the folios.  If there are any gaps, we will
 319	 * need to reread the entire directory contents.
 320	 */
 321	i = req->nr_pages;
 322	while (i < nr_pages) {
 323		struct folio *folio;
 324
 325		folio = filemap_get_folio(mapping, i);
 326		if (IS_ERR(folio)) {
 327			if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
 328				afs_stat_v(dvnode, n_inval);
 329			folio = __filemap_get_folio(mapping,
 330						    i, FGP_LOCK | FGP_CREAT,
 331						    mapping->gfp_mask);
 332			if (IS_ERR(folio)) {
 333				ret = PTR_ERR(folio);
 334				goto error;
 335			}
 336			folio_attach_private(folio, (void *)1);
 337			folio_unlock(folio);
 338		}
 339
 340		req->nr_pages += folio_nr_pages(folio);
 341		i += folio_nr_pages(folio);
 342	}
 343
 344	/* If we're going to reload, we need to lock all the pages to prevent
 345	 * races.
 346	 */
 347	ret = -ERESTARTSYS;
 348	if (down_read_killable(&dvnode->validate_lock) < 0)
 349		goto error;
 350
 351	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
 352		goto success;
 353
 354	up_read(&dvnode->validate_lock);
 355	if (down_write_killable(&dvnode->validate_lock) < 0)
 356		goto error;
 357
 358	if (!test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
 359		trace_afs_reload_dir(dvnode);
 360		ret = afs_fetch_data(dvnode, req);
 361		if (ret < 0)
 362			goto error_unlock;
 363
 364		task_io_account_read(PAGE_SIZE * req->nr_pages);
 365
 366		if (req->len < req->file_size) {
 367			/* The content has grown, so we need to expand the
 368			 * buffer.
 369			 */
 370			up_write(&dvnode->validate_lock);
 371			remote_size = req->file_size;
 372			goto expand;
 373		}
 374
 375		/* Validate the data we just read. */
 376		ret = afs_dir_check(dvnode, req);
 377		if (ret < 0)
 378			goto error_unlock;
 379
 380		// TODO: Trim excess pages
 381
 382		set_bit(AFS_VNODE_DIR_VALID, &dvnode->flags);
 383	}
 384
 385	downgrade_write(&dvnode->validate_lock);
 386success:
 387	return req;
 388
 389error_unlock:
 390	up_write(&dvnode->validate_lock);
 391error:
 392	afs_put_read(req);
 393	_leave(" = %d", ret);
 394	return ERR_PTR(ret);
 395}
 396
 397/*
 398 * deal with one block in an AFS directory
 399 */
 400static int afs_dir_iterate_block(struct afs_vnode *dvnode,
 401				 struct dir_context *ctx,
 402				 union afs_xdr_dir_block *block,
 403				 unsigned blkoff)
 404{
 405	union afs_xdr_dirent *dire;
 406	unsigned offset, next, curr, nr_slots;
 407	size_t nlen;
 408	int tmp;
 409
 410	_enter("%llx,%x", ctx->pos, blkoff);
 411
 412	curr = (ctx->pos - blkoff) / sizeof(union afs_xdr_dirent);
 413
 414	/* walk through the block, an entry at a time */
 415	for (offset = (blkoff == 0 ? AFS_DIR_RESV_BLOCKS0 : AFS_DIR_RESV_BLOCKS);
 416	     offset < AFS_DIR_SLOTS_PER_BLOCK;
 417	     offset = next
 418	     ) {
 419		/* skip entries marked unused in the bitmap */
 420		if (!(block->hdr.bitmap[offset / 8] &
 421		      (1 << (offset % 8)))) {
 422			_debug("ENT[%zu.%u]: unused",
 423			       blkoff / sizeof(union afs_xdr_dir_block), offset);
 424			next = offset + 1;
 425			if (offset >= curr)
 426				ctx->pos = blkoff +
 427					next * sizeof(union afs_xdr_dirent);
 428			continue;
 429		}
 430
 431		/* got a valid entry */
 432		dire = &block->dirents[offset];
 433		nlen = strnlen(dire->u.name,
 434			       sizeof(*block) -
 435			       offset * sizeof(union afs_xdr_dirent));
 436		if (nlen > AFSNAMEMAX - 1) {
 437			_debug("ENT[%zu]: name too long (len %u/%zu)",
 438			       blkoff / sizeof(union afs_xdr_dir_block),
 439			       offset, nlen);
 440			return afs_bad(dvnode, afs_file_error_dir_name_too_long);
 441		}
 442
 443		_debug("ENT[%zu.%u]: %s %zu \"%s\"",
 444		       blkoff / sizeof(union afs_xdr_dir_block), offset,
 445		       (offset < curr ? "skip" : "fill"),
 446		       nlen, dire->u.name);
 447
 448		nr_slots = afs_dir_calc_slots(nlen);
 449		next = offset + nr_slots;
 450		if (next > AFS_DIR_SLOTS_PER_BLOCK) {
 451			_debug("ENT[%zu.%u]:"
 452			       " %u extends beyond end dir block"
 453			       " (len %zu)",
 454			       blkoff / sizeof(union afs_xdr_dir_block),
 455			       offset, next, nlen);
 456			return afs_bad(dvnode, afs_file_error_dir_over_end);
 457		}
 458
 459		/* Check that the name-extension dirents are all allocated */
 460		for (tmp = 1; tmp < nr_slots; tmp++) {
 461			unsigned int ix = offset + tmp;
 462			if (!(block->hdr.bitmap[ix / 8] & (1 << (ix % 8)))) {
 463				_debug("ENT[%zu.u]:"
 464				       " %u unmarked extension (%u/%u)",
 465				       blkoff / sizeof(union afs_xdr_dir_block),
 466				       offset, tmp, nr_slots);
 467				return afs_bad(dvnode, afs_file_error_dir_unmarked_ext);
 468			}
 469		}
 470
 471		/* skip if starts before the current position */
 472		if (offset < curr) {
 473			if (next > curr)
 474				ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
 475			continue;
 476		}
 477
 478		/* found the next entry */
 479		if (!dir_emit(ctx, dire->u.name, nlen,
 480			      ntohl(dire->u.vnode),
 481			      (ctx->actor == afs_lookup_filldir ||
 482			       ctx->actor == afs_lookup_one_filldir)?
 483			      ntohl(dire->u.unique) : DT_UNKNOWN)) {
 484			_leave(" = 0 [full]");
 485			return 0;
 486		}
 487
 488		ctx->pos = blkoff + next * sizeof(union afs_xdr_dirent);
 489	}
 490
 491	_leave(" = 1 [more]");
 492	return 1;
 493}
 494
 495/*
 496 * iterate through the data blob that lists the contents of an AFS directory
 497 */
 498static int afs_dir_iterate(struct inode *dir, struct dir_context *ctx,
 499			   struct key *key, afs_dataversion_t *_dir_version)
 500{
 501	struct afs_vnode *dvnode = AFS_FS_I(dir);
 502	union afs_xdr_dir_block *dblock;
 503	struct afs_read *req;
 504	struct folio *folio;
 505	unsigned offset, size;
 506	int ret;
 507
 508	_enter("{%lu},%u,,", dir->i_ino, (unsigned)ctx->pos);
 509
 510	if (test_bit(AFS_VNODE_DELETED, &AFS_FS_I(dir)->flags)) {
 511		_leave(" = -ESTALE");
 512		return -ESTALE;
 513	}
 514
 515	req = afs_read_dir(dvnode, key);
 516	if (IS_ERR(req))
 517		return PTR_ERR(req);
 518	*_dir_version = req->data_version;
 519
 520	/* round the file position up to the next entry boundary */
 521	ctx->pos += sizeof(union afs_xdr_dirent) - 1;
 522	ctx->pos &= ~(sizeof(union afs_xdr_dirent) - 1);
 523
 524	/* walk through the blocks in sequence */
 525	ret = 0;
 526	while (ctx->pos < req->actual_len) {
 527		/* Fetch the appropriate folio from the directory and re-add it
 528		 * to the LRU.  We have all the pages pinned with an extra ref.
 529		 */
 530		folio = __filemap_get_folio(dir->i_mapping, ctx->pos / PAGE_SIZE,
 531					    FGP_ACCESSED, 0);
 532		if (IS_ERR(folio)) {
 533			ret = afs_bad(dvnode, afs_file_error_dir_missing_page);
 534			break;
 535		}
 536
 537		offset = round_down(ctx->pos, sizeof(*dblock)) - folio_pos(folio);
 538		size = min_t(loff_t, folio_size(folio),
 539			     req->actual_len - folio_pos(folio));
 540
 541		do {
 542			dblock = kmap_local_folio(folio, offset);
 543			ret = afs_dir_iterate_block(dvnode, ctx, dblock,
 544						    folio_pos(folio) + offset);
 545			kunmap_local(dblock);
 546			if (ret != 1)
 547				goto out;
 548
 549		} while (offset += sizeof(*dblock), offset < size);
 550
 551		ret = 0;
 552	}
 553
 554out:
 555	up_read(&dvnode->validate_lock);
 556	afs_put_read(req);
 557	_leave(" = %d", ret);
 558	return ret;
 559}
 560
 561/*
 562 * read an AFS directory
 563 */
 564static int afs_readdir(struct file *file, struct dir_context *ctx)
 565{
 566	afs_dataversion_t dir_version;
 567
 568	return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file),
 569			       &dir_version);
 570}
 571
 572/*
 573 * Search the directory for a single name
 574 * - if afs_dir_iterate_block() spots this function, it'll pass the FID
 575 *   uniquifier through dtype
 576 */
 577static bool afs_lookup_one_filldir(struct dir_context *ctx, const char *name,
 578				  int nlen, loff_t fpos, u64 ino, unsigned dtype)
 579{
 580	struct afs_lookup_one_cookie *cookie =
 581		container_of(ctx, struct afs_lookup_one_cookie, ctx);
 582
 583	_enter("{%s,%u},%s,%u,,%llu,%u",
 584	       cookie->name.name, cookie->name.len, name, nlen,
 585	       (unsigned long long) ino, dtype);
 586
 587	/* insanity checks first */
 588	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 589	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 590
 591	if (cookie->name.len != nlen ||
 592	    memcmp(cookie->name.name, name, nlen) != 0) {
 593		_leave(" = true [keep looking]");
 594		return true;
 595	}
 596
 597	cookie->fid.vnode = ino;
 598	cookie->fid.unique = dtype;
 599	cookie->found = 1;
 600
 601	_leave(" = false [found]");
 602	return false;
 603}
 604
 605/*
 606 * Do a lookup of a single name in a directory
 607 * - just returns the FID the dentry name maps to if found
 608 */
 609static int afs_do_lookup_one(struct inode *dir, struct dentry *dentry,
 610			     struct afs_fid *fid, struct key *key,
 611			     afs_dataversion_t *_dir_version)
 612{
 613	struct afs_super_info *as = dir->i_sb->s_fs_info;
 614	struct afs_lookup_one_cookie cookie = {
 615		.ctx.actor = afs_lookup_one_filldir,
 616		.name = dentry->d_name,
 617		.fid.vid = as->volume->vid
 618	};
 619	int ret;
 620
 621	_enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
 622
 623	/* search the directory */
 624	ret = afs_dir_iterate(dir, &cookie.ctx, key, _dir_version);
 625	if (ret < 0) {
 626		_leave(" = %d [iter]", ret);
 627		return ret;
 628	}
 629
 630	if (!cookie.found) {
 631		_leave(" = -ENOENT [not found]");
 632		return -ENOENT;
 633	}
 634
 635	*fid = cookie.fid;
 636	_leave(" = 0 { vn=%llu u=%u }", fid->vnode, fid->unique);
 637	return 0;
 638}
 639
 640/*
 641 * search the directory for a name
 642 * - if afs_dir_iterate_block() spots this function, it'll pass the FID
 643 *   uniquifier through dtype
 644 */
 645static bool afs_lookup_filldir(struct dir_context *ctx, const char *name,
 646			      int nlen, loff_t fpos, u64 ino, unsigned dtype)
 647{
 648	struct afs_lookup_cookie *cookie =
 649		container_of(ctx, struct afs_lookup_cookie, ctx);
 650
 651	_enter("{%s,%u},%s,%u,,%llu,%u",
 652	       cookie->name.name, cookie->name.len, name, nlen,
 653	       (unsigned long long) ino, dtype);
 654
 655	/* insanity checks first */
 656	BUILD_BUG_ON(sizeof(union afs_xdr_dir_block) != 2048);
 657	BUILD_BUG_ON(sizeof(union afs_xdr_dirent) != 32);
 658
 659	if (cookie->found) {
 660		if (cookie->nr_fids < 50) {
 661			cookie->fids[cookie->nr_fids].vnode	= ino;
 662			cookie->fids[cookie->nr_fids].unique	= dtype;
 663			cookie->nr_fids++;
 664		}
 665	} else if (cookie->name.len == nlen &&
 666		   memcmp(cookie->name.name, name, nlen) == 0) {
 667		cookie->fids[1].vnode	= ino;
 668		cookie->fids[1].unique	= dtype;
 669		cookie->found = 1;
 670		if (cookie->one_only)
 671			return false;
 672	}
 673
 674	return cookie->nr_fids < 50;
 675}
 676
 677/*
 678 * Deal with the result of a successful lookup operation.  Turn all the files
 679 * into inodes and save the first one - which is the one we actually want.
 680 */
 681static void afs_do_lookup_success(struct afs_operation *op)
 682{
 683	struct afs_vnode_param *vp;
 684	struct afs_vnode *vnode;
 685	struct inode *inode;
 686	u32 abort_code;
 687	int i;
 688
 689	_enter("");
 690
 691	for (i = 0; i < op->nr_files; i++) {
 692		switch (i) {
 693		case 0:
 694			vp = &op->file[0];
 695			abort_code = vp->scb.status.abort_code;
 696			if (abort_code != 0) {
 697				op->call_abort_code = abort_code;
 698				afs_op_set_error(op, afs_abort_to_error(abort_code));
 699				op->cumul_error.abort_code = abort_code;
 700			}
 701			break;
 702
 703		case 1:
 704			vp = &op->file[1];
 705			break;
 706
 707		default:
 708			vp = &op->more_files[i - 2];
 709			break;
 710		}
 711
 712		if (vp->scb.status.abort_code)
 713			trace_afs_bulkstat_error(op, &vp->fid, i, vp->scb.status.abort_code);
 714		if (!vp->scb.have_status && !vp->scb.have_error)
 715			continue;
 716
 717		_debug("do [%u]", i);
 718		if (vp->vnode) {
 719			if (!test_bit(AFS_VNODE_UNSET, &vp->vnode->flags))
 720				afs_vnode_commit_status(op, vp);
 721		} else if (vp->scb.status.abort_code == 0) {
 722			inode = afs_iget(op, vp);
 723			if (!IS_ERR(inode)) {
 724				vnode = AFS_FS_I(inode);
 725				afs_cache_permit(vnode, op->key,
 726						 0 /* Assume vnode->cb_break is 0 */ +
 727						 op->cb_v_break,
 728						 &vp->scb);
 729				vp->vnode = vnode;
 730				vp->put_vnode = true;
 731			}
 732		} else {
 733			_debug("- abort %d %llx:%llx.%x",
 734			       vp->scb.status.abort_code,
 735			       vp->fid.vid, vp->fid.vnode, vp->fid.unique);
 736		}
 737	}
 738
 739	_leave("");
 740}
 741
 742static const struct afs_operation_ops afs_inline_bulk_status_operation = {
 743	.issue_afs_rpc	= afs_fs_inline_bulk_status,
 744	.issue_yfs_rpc	= yfs_fs_inline_bulk_status,
 745	.success	= afs_do_lookup_success,
 746};
 747
 748static const struct afs_operation_ops afs_lookup_fetch_status_operation = {
 749	.issue_afs_rpc	= afs_fs_fetch_status,
 750	.issue_yfs_rpc	= yfs_fs_fetch_status,
 751	.success	= afs_do_lookup_success,
 752	.aborted	= afs_check_for_remote_deletion,
 753};
 754
 755/*
 756 * See if we know that the server we expect to use doesn't support
 757 * FS.InlineBulkStatus.
 758 */
 759static bool afs_server_supports_ibulk(struct afs_vnode *dvnode)
 760{
 761	struct afs_server_list *slist;
 762	struct afs_volume *volume = dvnode->volume;
 763	struct afs_server *server;
 764	bool ret = true;
 765	int i;
 766
 767	if (!test_bit(AFS_VOLUME_MAYBE_NO_IBULK, &volume->flags))
 768		return true;
 769
 770	rcu_read_lock();
 771	slist = rcu_dereference(volume->servers);
 772
 773	for (i = 0; i < slist->nr_servers; i++) {
 774		server = slist->servers[i].server;
 775		if (server == dvnode->cb_server) {
 776			if (test_bit(AFS_SERVER_FL_NO_IBULK, &server->flags))
 777				ret = false;
 778			break;
 779		}
 780	}
 781
 782	rcu_read_unlock();
 783	return ret;
 784}
 785
 786/*
 787 * Do a lookup in a directory.  We make use of bulk lookup to query a slew of
 788 * files in one go and create inodes for them.  The inode of the file we were
 789 * asked for is returned.
 790 */
 791static struct inode *afs_do_lookup(struct inode *dir, struct dentry *dentry,
 792				   struct key *key)
 793{
 794	struct afs_lookup_cookie *cookie;
 795	struct afs_vnode_param *vp;
 796	struct afs_operation *op;
 797	struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode;
 798	struct inode *inode = NULL, *ti;
 799	afs_dataversion_t data_version = READ_ONCE(dvnode->status.data_version);
 800	long ret;
 801	int i;
 802
 803	_enter("{%lu},%p{%pd},", dir->i_ino, dentry, dentry);
 804
 805	cookie = kzalloc(sizeof(struct afs_lookup_cookie), GFP_KERNEL);
 806	if (!cookie)
 807		return ERR_PTR(-ENOMEM);
 808
 809	for (i = 0; i < ARRAY_SIZE(cookie->fids); i++)
 810		cookie->fids[i].vid = dvnode->fid.vid;
 811	cookie->ctx.actor = afs_lookup_filldir;
 812	cookie->name = dentry->d_name;
 813	cookie->nr_fids = 2; /* slot 1 is saved for the fid we actually want
 814			      * and slot 0 for the directory */
 815
 816	if (!afs_server_supports_ibulk(dvnode))
 817		cookie->one_only = true;
 818
 819	/* search the directory */
 820	ret = afs_dir_iterate(dir, &cookie->ctx, key, &data_version);
 821	if (ret < 0)
 822		goto out;
 823
 824	dentry->d_fsdata = (void *)(unsigned long)data_version;
 825
 826	ret = -ENOENT;
 827	if (!cookie->found)
 828		goto out;
 829
 830	/* Check to see if we already have an inode for the primary fid. */
 831	inode = ilookup5(dir->i_sb, cookie->fids[1].vnode,
 832			 afs_ilookup5_test_by_fid, &cookie->fids[1]);
 833	if (inode)
 834		goto out; /* We do */
 835
 836	/* Okay, we didn't find it.  We need to query the server - and whilst
 837	 * we're doing that, we're going to attempt to look up a bunch of other
 838	 * vnodes also.
 839	 */
 840	op = afs_alloc_operation(NULL, dvnode->volume);
 841	if (IS_ERR(op)) {
 842		ret = PTR_ERR(op);
 843		goto out;
 844	}
 845
 846	afs_op_set_vnode(op, 0, dvnode);
 847	afs_op_set_fid(op, 1, &cookie->fids[1]);
 848
 849	op->nr_files = cookie->nr_fids;
 850	_debug("nr_files %u", op->nr_files);
 851
 852	/* Need space for examining all the selected files */
 853	if (op->nr_files > 2) {
 854		op->more_files = kvcalloc(op->nr_files - 2,
 855					  sizeof(struct afs_vnode_param),
 856					  GFP_KERNEL);
 857		if (!op->more_files) {
 858			afs_op_nomem(op);
 859			goto out_op;
 860		}
 861
 862		for (i = 2; i < op->nr_files; i++) {
 863			vp = &op->more_files[i - 2];
 864			vp->fid = cookie->fids[i];
 865
 866			/* Find any inodes that already exist and get their
 867			 * callback counters.
 868			 */
 869			ti = ilookup5_nowait(dir->i_sb, vp->fid.vnode,
 870					     afs_ilookup5_test_by_fid, &vp->fid);
 871			if (!IS_ERR_OR_NULL(ti)) {
 872				vnode = AFS_FS_I(ti);
 873				vp->dv_before = vnode->status.data_version;
 874				vp->cb_break_before = afs_calc_vnode_cb_break(vnode);
 875				vp->vnode = vnode;
 876				vp->put_vnode = true;
 877				vp->speculative = true; /* vnode not locked */
 878			}
 879		}
 880	}
 881
 882	/* Try FS.InlineBulkStatus first.  Abort codes for the individual
 883	 * lookups contained therein are stored in the reply without aborting
 884	 * the whole operation.
 885	 */
 886	afs_op_set_error(op, -ENOTSUPP);
 887	if (!cookie->one_only) {
 888		op->ops = &afs_inline_bulk_status_operation;
 889		afs_begin_vnode_operation(op);
 890		afs_wait_for_operation(op);
 891	}
 892
 893	if (afs_op_error(op) == -ENOTSUPP) {
 894		/* We could try FS.BulkStatus next, but this aborts the entire
 895		 * op if any of the lookups fails - so, for the moment, revert
 896		 * to FS.FetchStatus for op->file[1].
 897		 */
 898		op->fetch_status.which = 1;
 899		op->ops = &afs_lookup_fetch_status_operation;
 900		afs_begin_vnode_operation(op);
 901		afs_wait_for_operation(op);
 902	}
 903
 904out_op:
 905	if (!afs_op_error(op)) {
 906		if (op->file[1].scb.status.abort_code) {
 907			afs_op_accumulate_error(op, -ECONNABORTED,
 908						op->file[1].scb.status.abort_code);
 909		} else {
 910			inode = &op->file[1].vnode->netfs.inode;
 911			op->file[1].vnode = NULL;
 912		}
 913	}
 914
 915	if (op->file[0].scb.have_status)
 916		dentry->d_fsdata = (void *)(unsigned long)op->file[0].scb.status.data_version;
 917	else
 918		dentry->d_fsdata = (void *)(unsigned long)op->file[0].dv_before;
 919	ret = afs_put_operation(op);
 920out:
 921	kfree(cookie);
 922	_leave("");
 923	return inode ?: ERR_PTR(ret);
 924}
 925
 926/*
 927 * Look up an entry in a directory with @sys substitution.
 928 */
 929static struct dentry *afs_lookup_atsys(struct inode *dir, struct dentry *dentry,
 930				       struct key *key)
 931{
 932	struct afs_sysnames *subs;
 933	struct afs_net *net = afs_i2net(dir);
 934	struct dentry *ret;
 935	char *buf, *p, *name;
 936	int len, i;
 937
 938	_enter("");
 939
 940	ret = ERR_PTR(-ENOMEM);
 941	p = buf = kmalloc(AFSNAMEMAX, GFP_KERNEL);
 942	if (!buf)
 943		goto out_p;
 944	if (dentry->d_name.len > 4) {
 945		memcpy(p, dentry->d_name.name, dentry->d_name.len - 4);
 946		p += dentry->d_name.len - 4;
 947	}
 948
 949	/* There is an ordered list of substitutes that we have to try. */
 950	read_lock(&net->sysnames_lock);
 951	subs = net->sysnames;
 952	refcount_inc(&subs->usage);
 953	read_unlock(&net->sysnames_lock);
 954
 955	for (i = 0; i < subs->nr; i++) {
 956		name = subs->subs[i];
 957		len = dentry->d_name.len - 4 + strlen(name);
 958		if (len >= AFSNAMEMAX) {
 959			ret = ERR_PTR(-ENAMETOOLONG);
 960			goto out_s;
 961		}
 962
 963		strcpy(p, name);
 964		ret = lookup_one_len(buf, dentry->d_parent, len);
 965		if (IS_ERR(ret) || d_is_positive(ret))
 966			goto out_s;
 967		dput(ret);
 968	}
 969
 970	/* We don't want to d_add() the @sys dentry here as we don't want to
 971	 * the cached dentry to hide changes to the sysnames list.
 972	 */
 973	ret = NULL;
 974out_s:
 975	afs_put_sysnames(subs);
 976	kfree(buf);
 977out_p:
 978	key_put(key);
 979	return ret;
 980}
 981
 982/*
 983 * look up an entry in a directory
 984 */
 985static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry,
 986				 unsigned int flags)
 987{
 988	struct afs_vnode *dvnode = AFS_FS_I(dir);
 989	struct afs_fid fid = {};
 990	struct inode *inode;
 991	struct dentry *d;
 992	struct key *key;
 993	int ret;
 994
 995	_enter("{%llx:%llu},%p{%pd},",
 996	       dvnode->fid.vid, dvnode->fid.vnode, dentry, dentry);
 997
 998	ASSERTCMP(d_inode(dentry), ==, NULL);
 999
1000	if (dentry->d_name.len >= AFSNAMEMAX) {
1001		_leave(" = -ENAMETOOLONG");
1002		return ERR_PTR(-ENAMETOOLONG);
1003	}
1004
1005	if (test_bit(AFS_VNODE_DELETED, &dvnode->flags)) {
1006		_leave(" = -ESTALE");
1007		return ERR_PTR(-ESTALE);
1008	}
1009
1010	key = afs_request_key(dvnode->volume->cell);
1011	if (IS_ERR(key)) {
1012		_leave(" = %ld [key]", PTR_ERR(key));
1013		return ERR_CAST(key);
1014	}
1015
1016	ret = afs_validate(dvnode, key);
1017	if (ret < 0) {
1018		key_put(key);
1019		_leave(" = %d [val]", ret);
1020		return ERR_PTR(ret);
1021	}
1022
1023	if (dentry->d_name.len >= 4 &&
1024	    dentry->d_name.name[dentry->d_name.len - 4] == '@' &&
1025	    dentry->d_name.name[dentry->d_name.len - 3] == 's' &&
1026	    dentry->d_name.name[dentry->d_name.len - 2] == 'y' &&
1027	    dentry->d_name.name[dentry->d_name.len - 1] == 's')
1028		return afs_lookup_atsys(dir, dentry, key);
1029
1030	afs_stat_v(dvnode, n_lookup);
1031	inode = afs_do_lookup(dir, dentry, key);
1032	key_put(key);
1033	if (inode == ERR_PTR(-ENOENT))
1034		inode = afs_try_auto_mntpt(dentry, dir);
1035
1036	if (!IS_ERR_OR_NULL(inode))
1037		fid = AFS_FS_I(inode)->fid;
1038
1039	_debug("splice %p", dentry->d_inode);
1040	d = d_splice_alias(inode, dentry);
1041	if (!IS_ERR_OR_NULL(d)) {
1042		d->d_fsdata = dentry->d_fsdata;
1043		trace_afs_lookup(dvnode, &d->d_name, &fid);
1044	} else {
1045		trace_afs_lookup(dvnode, &dentry->d_name, &fid);
1046	}
1047	_leave("");
1048	return d;
1049}
1050
1051/*
1052 * Check the validity of a dentry under RCU conditions.
1053 */
1054static int afs_d_revalidate_rcu(struct dentry *dentry)
1055{
1056	struct afs_vnode *dvnode;
1057	struct dentry *parent;
1058	struct inode *dir;
1059	long dir_version, de_version;
1060
1061	_enter("%p", dentry);
1062
1063	/* Check the parent directory is still valid first. */
1064	parent = READ_ONCE(dentry->d_parent);
1065	dir = d_inode_rcu(parent);
1066	if (!dir)
1067		return -ECHILD;
1068	dvnode = AFS_FS_I(dir);
1069	if (test_bit(AFS_VNODE_DELETED, &dvnode->flags))
1070		return -ECHILD;
1071
1072	if (!afs_check_validity(dvnode))
1073		return -ECHILD;
1074
1075	/* We only need to invalidate a dentry if the server's copy changed
1076	 * behind our back.  If we made the change, it's no problem.  Note that
1077	 * on a 32-bit system, we only have 32 bits in the dentry to store the
1078	 * version.
1079	 */
1080	dir_version = (long)READ_ONCE(dvnode->status.data_version);
1081	de_version = (long)READ_ONCE(dentry->d_fsdata);
1082	if (de_version != dir_version) {
1083		dir_version = (long)READ_ONCE(dvnode->invalid_before);
1084		if (de_version - dir_version < 0)
1085			return -ECHILD;
1086	}
1087
1088	return 1; /* Still valid */
1089}
1090
1091/*
1092 * check that a dentry lookup hit has found a valid entry
1093 * - NOTE! the hit can be a negative hit too, so we can't assume we have an
1094 *   inode
1095 */
1096static int afs_d_revalidate(struct dentry *dentry, unsigned int flags)
1097{
1098	struct afs_vnode *vnode, *dir;
1099	struct afs_fid fid;
1100	struct dentry *parent;
1101	struct inode *inode;
1102	struct key *key;
1103	afs_dataversion_t dir_version, invalid_before;
1104	long de_version;
1105	int ret;
1106
1107	if (flags & LOOKUP_RCU)
1108		return afs_d_revalidate_rcu(dentry);
1109
1110	if (d_really_is_positive(dentry)) {
1111		vnode = AFS_FS_I(d_inode(dentry));
1112		_enter("{v={%llx:%llu} n=%pd fl=%lx},",
1113		       vnode->fid.vid, vnode->fid.vnode, dentry,
1114		       vnode->flags);
1115	} else {
1116		_enter("{neg n=%pd}", dentry);
1117	}
1118
1119	key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell);
1120	if (IS_ERR(key))
1121		key = NULL;
1122
1123	/* Hold the parent dentry so we can peer at it */
1124	parent = dget_parent(dentry);
1125	dir = AFS_FS_I(d_inode(parent));
1126
1127	/* validate the parent directory */
1128	ret = afs_validate(dir, key);
1129	if (ret == -ERESTARTSYS) {
1130		dput(parent);
1131		key_put(key);
1132		return ret;
1133	}
1134
1135	if (test_bit(AFS_VNODE_DELETED, &dir->flags)) {
1136		_debug("%pd: parent dir deleted", dentry);
1137		goto not_found;
1138	}
1139
1140	/* We only need to invalidate a dentry if the server's copy changed
1141	 * behind our back.  If we made the change, it's no problem.  Note that
1142	 * on a 32-bit system, we only have 32 bits in the dentry to store the
1143	 * version.
1144	 */
1145	dir_version = dir->status.data_version;
1146	de_version = (long)dentry->d_fsdata;
1147	if (de_version == (long)dir_version)
1148		goto out_valid_noupdate;
1149
1150	invalid_before = dir->invalid_before;
1151	if (de_version - (long)invalid_before >= 0)
1152		goto out_valid;
1153
1154	_debug("dir modified");
1155	afs_stat_v(dir, n_reval);
1156
1157	/* search the directory for this vnode */
1158	ret = afs_do_lookup_one(&dir->netfs.inode, dentry, &fid, key, &dir_version);
1159	switch (ret) {
1160	case 0:
1161		/* the filename maps to something */
1162		if (d_really_is_negative(dentry))
1163			goto not_found;
1164		inode = d_inode(dentry);
1165		if (is_bad_inode(inode)) {
1166			printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n",
1167			       dentry);
1168			goto not_found;
1169		}
1170
1171		vnode = AFS_FS_I(inode);
1172
1173		/* if the vnode ID has changed, then the dirent points to a
1174		 * different file */
1175		if (fid.vnode != vnode->fid.vnode) {
1176			_debug("%pd: dirent changed [%llu != %llu]",
1177			       dentry, fid.vnode,
1178			       vnode->fid.vnode);
1179			goto not_found;
1180		}
1181
1182		/* if the vnode ID uniqifier has changed, then the file has
1183		 * been deleted and replaced, and the original vnode ID has
1184		 * been reused */
1185		if (fid.unique != vnode->fid.unique) {
1186			_debug("%pd: file deleted (uq %u -> %u I:%u)",
1187			       dentry, fid.unique,
1188			       vnode->fid.unique,
1189			       vnode->netfs.inode.i_generation);
1190			goto not_found;
1191		}
1192		goto out_valid;
1193
1194	case -ENOENT:
1195		/* the filename is unknown */
1196		_debug("%pd: dirent not found", dentry);
1197		if (d_really_is_positive(dentry))
1198			goto not_found;
1199		goto out_valid;
1200
1201	default:
1202		_debug("failed to iterate dir %pd: %d",
1203		       parent, ret);
1204		goto not_found;
1205	}
1206
1207out_valid:
1208	dentry->d_fsdata = (void *)(unsigned long)dir_version;
1209out_valid_noupdate:
1210	dput(parent);
1211	key_put(key);
1212	_leave(" = 1 [valid]");
1213	return 1;
1214
1215not_found:
1216	_debug("dropping dentry %pd2", dentry);
1217	dput(parent);
1218	key_put(key);
1219
1220	_leave(" = 0 [bad]");
1221	return 0;
1222}
1223
1224/*
1225 * allow the VFS to enquire as to whether a dentry should be unhashed (mustn't
1226 * sleep)
1227 * - called from dput() when d_count is going to 0.
1228 * - return 1 to request dentry be unhashed, 0 otherwise
1229 */
1230static int afs_d_delete(const struct dentry *dentry)
1231{
1232	_enter("%pd", dentry);
1233
1234	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1235		goto zap;
1236
1237	if (d_really_is_positive(dentry) &&
1238	    (test_bit(AFS_VNODE_DELETED,   &AFS_FS_I(d_inode(dentry))->flags) ||
1239	     test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(d_inode(dentry))->flags)))
1240		goto zap;
1241
1242	_leave(" = 0 [keep]");
1243	return 0;
1244
1245zap:
1246	_leave(" = 1 [zap]");
1247	return 1;
1248}
1249
1250/*
1251 * Clean up sillyrename files on dentry removal.
1252 */
1253static void afs_d_iput(struct dentry *dentry, struct inode *inode)
1254{
1255	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1256		afs_silly_iput(dentry, inode);
1257	iput(inode);
1258}
1259
1260/*
1261 * handle dentry release
1262 */
1263void afs_d_release(struct dentry *dentry)
1264{
1265	_enter("%pd", dentry);
1266}
1267
1268void afs_check_for_remote_deletion(struct afs_operation *op)
1269{
1270	struct afs_vnode *vnode = op->file[0].vnode;
1271
1272	switch (afs_op_abort_code(op)) {
1273	case VNOVNODE:
1274		set_bit(AFS_VNODE_DELETED, &vnode->flags);
1275		clear_nlink(&vnode->netfs.inode);
1276		afs_break_callback(vnode, afs_cb_break_for_deleted);
1277	}
1278}
1279
1280/*
1281 * Create a new inode for create/mkdir/symlink
1282 */
1283static void afs_vnode_new_inode(struct afs_operation *op)
1284{
1285	struct afs_vnode_param *vp = &op->file[1];
1286	struct afs_vnode *vnode;
1287	struct inode *inode;
1288
1289	_enter("");
1290
1291	ASSERTCMP(afs_op_error(op), ==, 0);
1292
1293	inode = afs_iget(op, vp);
1294	if (IS_ERR(inode)) {
1295		/* ENOMEM or EINTR at a really inconvenient time - just abandon
1296		 * the new directory on the server.
1297		 */
1298		afs_op_accumulate_error(op, PTR_ERR(inode), 0);
1299		return;
1300	}
1301
1302	vnode = AFS_FS_I(inode);
1303	set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
1304	if (!afs_op_error(op))
1305		afs_cache_permit(vnode, op->key, vnode->cb_break, &vp->scb);
1306	d_instantiate(op->dentry, inode);
1307}
1308
1309static void afs_create_success(struct afs_operation *op)
1310{
1311	_enter("op=%08x", op->debug_id);
1312	op->ctime = op->file[0].scb.status.mtime_client;
1313	afs_vnode_commit_status(op, &op->file[0]);
1314	afs_update_dentry_version(op, &op->file[0], op->dentry);
1315	afs_vnode_new_inode(op);
1316}
1317
1318static void afs_create_edit_dir(struct afs_operation *op)
1319{
1320	struct afs_vnode_param *dvp = &op->file[0];
1321	struct afs_vnode_param *vp = &op->file[1];
1322	struct afs_vnode *dvnode = dvp->vnode;
1323
1324	_enter("op=%08x", op->debug_id);
1325
1326	down_write(&dvnode->validate_lock);
1327	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1328	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1329		afs_edit_dir_add(dvnode, &op->dentry->d_name, &vp->fid,
1330				 op->create.reason);
1331	up_write(&dvnode->validate_lock);
1332}
1333
1334static void afs_create_put(struct afs_operation *op)
1335{
1336	_enter("op=%08x", op->debug_id);
1337
1338	if (afs_op_error(op))
1339		d_drop(op->dentry);
1340}
1341
1342static const struct afs_operation_ops afs_mkdir_operation = {
1343	.issue_afs_rpc	= afs_fs_make_dir,
1344	.issue_yfs_rpc	= yfs_fs_make_dir,
1345	.success	= afs_create_success,
1346	.aborted	= afs_check_for_remote_deletion,
1347	.edit_dir	= afs_create_edit_dir,
1348	.put		= afs_create_put,
1349};
1350
1351/*
1352 * create a directory on an AFS filesystem
1353 */
1354static int afs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
1355		     struct dentry *dentry, umode_t mode)
1356{
1357	struct afs_operation *op;
1358	struct afs_vnode *dvnode = AFS_FS_I(dir);
1359
1360	_enter("{%llx:%llu},{%pd},%ho",
1361	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1362
1363	op = afs_alloc_operation(NULL, dvnode->volume);
1364	if (IS_ERR(op)) {
1365		d_drop(dentry);
1366		return PTR_ERR(op);
1367	}
1368
1369	afs_op_set_vnode(op, 0, dvnode);
1370	op->file[0].dv_delta = 1;
1371	op->file[0].modification = true;
1372	op->file[0].update_ctime = true;
1373	op->dentry	= dentry;
1374	op->create.mode	= S_IFDIR | mode;
1375	op->create.reason = afs_edit_dir_for_mkdir;
1376	op->mtime	= current_time(dir);
1377	op->ops		= &afs_mkdir_operation;
1378	return afs_do_sync_operation(op);
1379}
1380
1381/*
1382 * Remove a subdir from a directory.
1383 */
1384static void afs_dir_remove_subdir(struct dentry *dentry)
1385{
1386	if (d_really_is_positive(dentry)) {
1387		struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1388
1389		clear_nlink(&vnode->netfs.inode);
1390		set_bit(AFS_VNODE_DELETED, &vnode->flags);
1391		atomic64_set(&vnode->cb_expires_at, AFS_NO_CB_PROMISE);
1392		clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags);
1393	}
1394}
1395
1396static void afs_rmdir_success(struct afs_operation *op)
1397{
1398	_enter("op=%08x", op->debug_id);
1399	op->ctime = op->file[0].scb.status.mtime_client;
1400	afs_vnode_commit_status(op, &op->file[0]);
1401	afs_update_dentry_version(op, &op->file[0], op->dentry);
1402}
1403
1404static void afs_rmdir_edit_dir(struct afs_operation *op)
1405{
1406	struct afs_vnode_param *dvp = &op->file[0];
1407	struct afs_vnode *dvnode = dvp->vnode;
1408
1409	_enter("op=%08x", op->debug_id);
1410	afs_dir_remove_subdir(op->dentry);
1411
1412	down_write(&dvnode->validate_lock);
1413	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1414	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1415		afs_edit_dir_remove(dvnode, &op->dentry->d_name,
1416				    afs_edit_dir_for_rmdir);
1417	up_write(&dvnode->validate_lock);
1418}
1419
1420static void afs_rmdir_put(struct afs_operation *op)
1421{
1422	_enter("op=%08x", op->debug_id);
1423	if (op->file[1].vnode)
1424		up_write(&op->file[1].vnode->rmdir_lock);
1425}
1426
1427static const struct afs_operation_ops afs_rmdir_operation = {
1428	.issue_afs_rpc	= afs_fs_remove_dir,
1429	.issue_yfs_rpc	= yfs_fs_remove_dir,
1430	.success	= afs_rmdir_success,
1431	.aborted	= afs_check_for_remote_deletion,
1432	.edit_dir	= afs_rmdir_edit_dir,
1433	.put		= afs_rmdir_put,
1434};
1435
1436/*
1437 * remove a directory from an AFS filesystem
1438 */
1439static int afs_rmdir(struct inode *dir, struct dentry *dentry)
1440{
1441	struct afs_operation *op;
1442	struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode = NULL;
1443	int ret;
1444
1445	_enter("{%llx:%llu},{%pd}",
1446	       dvnode->fid.vid, dvnode->fid.vnode, dentry);
1447
1448	op = afs_alloc_operation(NULL, dvnode->volume);
1449	if (IS_ERR(op))
1450		return PTR_ERR(op);
1451
1452	afs_op_set_vnode(op, 0, dvnode);
1453	op->file[0].dv_delta = 1;
1454	op->file[0].modification = true;
1455	op->file[0].update_ctime = true;
1456
1457	op->dentry	= dentry;
1458	op->ops		= &afs_rmdir_operation;
1459
1460	/* Try to make sure we have a callback promise on the victim. */
1461	if (d_really_is_positive(dentry)) {
1462		vnode = AFS_FS_I(d_inode(dentry));
1463		ret = afs_validate(vnode, op->key);
1464		if (ret < 0)
1465			goto error;
1466	}
1467
1468	if (vnode) {
1469		ret = down_write_killable(&vnode->rmdir_lock);
1470		if (ret < 0)
1471			goto error;
1472		op->file[1].vnode = vnode;
1473	}
1474
1475	ret = afs_do_sync_operation(op);
1476
1477	/* Not all systems that can host afs servers have ENOTEMPTY. */
1478	if (ret == -EEXIST)
1479		ret = -ENOTEMPTY;
1480	return ret;
1481
1482error:
1483	return afs_put_operation(op);
1484}
1485
1486/*
1487 * Remove a link to a file or symlink from a directory.
1488 *
1489 * If the file was not deleted due to excess hard links, the fileserver will
1490 * break the callback promise on the file - if it had one - before it returns
1491 * to us, and if it was deleted, it won't
1492 *
1493 * However, if we didn't have a callback promise outstanding, or it was
1494 * outstanding on a different server, then it won't break it either...
1495 */
1496static void afs_dir_remove_link(struct afs_operation *op)
1497{
1498	struct afs_vnode *dvnode = op->file[0].vnode;
1499	struct afs_vnode *vnode = op->file[1].vnode;
1500	struct dentry *dentry = op->dentry;
1501	int ret;
1502
1503	if (afs_op_error(op) ||
1504	    (op->file[1].scb.have_status && op->file[1].scb.have_error))
1505		return;
1506	if (d_really_is_positive(dentry))
1507		return;
1508
1509	if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) {
1510		/* Already done */
1511	} else if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags)) {
1512		write_seqlock(&vnode->cb_lock);
1513		drop_nlink(&vnode->netfs.inode);
1514		if (vnode->netfs.inode.i_nlink == 0) {
1515			set_bit(AFS_VNODE_DELETED, &vnode->flags);
1516			__afs_break_callback(vnode, afs_cb_break_for_unlink);
1517		}
1518		write_sequnlock(&vnode->cb_lock);
1519	} else {
1520		afs_break_callback(vnode, afs_cb_break_for_unlink);
1521
1522		if (test_bit(AFS_VNODE_DELETED, &vnode->flags))
1523			_debug("AFS_VNODE_DELETED");
1524
1525		ret = afs_validate(vnode, op->key);
1526		if (ret != -ESTALE)
1527			afs_op_set_error(op, ret);
1528	}
1529
1530	_debug("nlink %d [val %d]", vnode->netfs.inode.i_nlink, afs_op_error(op));
1531}
1532
1533static void afs_unlink_success(struct afs_operation *op)
1534{
1535	_enter("op=%08x", op->debug_id);
1536	op->ctime = op->file[0].scb.status.mtime_client;
1537	afs_check_dir_conflict(op, &op->file[0]);
1538	afs_vnode_commit_status(op, &op->file[0]);
1539	afs_vnode_commit_status(op, &op->file[1]);
1540	afs_update_dentry_version(op, &op->file[0], op->dentry);
1541	afs_dir_remove_link(op);
1542}
1543
1544static void afs_unlink_edit_dir(struct afs_operation *op)
1545{
1546	struct afs_vnode_param *dvp = &op->file[0];
1547	struct afs_vnode *dvnode = dvp->vnode;
1548
1549	_enter("op=%08x", op->debug_id);
1550	down_write(&dvnode->validate_lock);
1551	if (test_bit(AFS_VNODE_DIR_VALID, &dvnode->flags) &&
1552	    dvnode->status.data_version == dvp->dv_before + dvp->dv_delta)
1553		afs_edit_dir_remove(dvnode, &op->dentry->d_name,
1554				    afs_edit_dir_for_unlink);
1555	up_write(&dvnode->validate_lock);
1556}
1557
1558static void afs_unlink_put(struct afs_operation *op)
1559{
1560	_enter("op=%08x", op->debug_id);
1561	if (op->unlink.need_rehash && afs_op_error(op) < 0 && afs_op_error(op) != -ENOENT)
1562		d_rehash(op->dentry);
1563}
1564
1565static const struct afs_operation_ops afs_unlink_operation = {
1566	.issue_afs_rpc	= afs_fs_remove_file,
1567	.issue_yfs_rpc	= yfs_fs_remove_file,
1568	.success	= afs_unlink_success,
1569	.aborted	= afs_check_for_remote_deletion,
1570	.edit_dir	= afs_unlink_edit_dir,
1571	.put		= afs_unlink_put,
1572};
1573
1574/*
1575 * Remove a file or symlink from an AFS filesystem.
1576 */
1577static int afs_unlink(struct inode *dir, struct dentry *dentry)
1578{
1579	struct afs_operation *op;
1580	struct afs_vnode *dvnode = AFS_FS_I(dir);
1581	struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry));
1582	int ret;
1583
1584	_enter("{%llx:%llu},{%pd}",
1585	       dvnode->fid.vid, dvnode->fid.vnode, dentry);
1586
1587	if (dentry->d_name.len >= AFSNAMEMAX)
1588		return -ENAMETOOLONG;
1589
1590	op = afs_alloc_operation(NULL, dvnode->volume);
1591	if (IS_ERR(op))
1592		return PTR_ERR(op);
1593
1594	afs_op_set_vnode(op, 0, dvnode);
1595	op->file[0].dv_delta = 1;
1596	op->file[0].modification = true;
1597	op->file[0].update_ctime = true;
1598
1599	/* Try to make sure we have a callback promise on the victim. */
1600	ret = afs_validate(vnode, op->key);
1601	if (ret < 0) {
1602		afs_op_set_error(op, ret);
1603		goto error;
1604	}
1605
1606	spin_lock(&dentry->d_lock);
1607	if (d_count(dentry) > 1) {
1608		spin_unlock(&dentry->d_lock);
1609		/* Start asynchronous writeout of the inode */
1610		write_inode_now(d_inode(dentry), 0);
1611		afs_op_set_error(op, afs_sillyrename(dvnode, vnode, dentry, op->key));
1612		goto error;
1613	}
1614	if (!d_unhashed(dentry)) {
1615		/* Prevent a race with RCU lookup. */
1616		__d_drop(dentry);
1617		op->unlink.need_rehash = true;
1618	}
1619	spin_unlock(&dentry->d_lock);
1620
1621	op->file[1].vnode = vnode;
1622	op->file[1].update_ctime = true;
1623	op->file[1].op_unlinked = true;
1624	op->dentry	= dentry;
1625	op->ops		= &afs_unlink_operation;
1626	afs_begin_vnode_operation(op);
1627	afs_wait_for_operation(op);
1628
1629	/* If there was a conflict with a third party, check the status of the
1630	 * unlinked vnode.
1631	 */
1632	if (afs_op_error(op) == 0 && (op->flags & AFS_OPERATION_DIR_CONFLICT)) {
1633		op->file[1].update_ctime = false;
1634		op->fetch_status.which = 1;
1635		op->ops = &afs_fetch_status_operation;
1636		afs_begin_vnode_operation(op);
1637		afs_wait_for_operation(op);
1638	}
1639
1640	return afs_put_operation(op);
1641
1642error:
1643	return afs_put_operation(op);
1644}
1645
1646static const struct afs_operation_ops afs_create_operation = {
1647	.issue_afs_rpc	= afs_fs_create_file,
1648	.issue_yfs_rpc	= yfs_fs_create_file,
1649	.success	= afs_create_success,
1650	.aborted	= afs_check_for_remote_deletion,
1651	.edit_dir	= afs_create_edit_dir,
1652	.put		= afs_create_put,
1653};
1654
1655/*
1656 * create a regular file on an AFS filesystem
1657 */
1658static int afs_create(struct mnt_idmap *idmap, struct inode *dir,
1659		      struct dentry *dentry, umode_t mode, bool excl)
1660{
1661	struct afs_operation *op;
1662	struct afs_vnode *dvnode = AFS_FS_I(dir);
1663	int ret = -ENAMETOOLONG;
1664
1665	_enter("{%llx:%llu},{%pd},%ho",
1666	       dvnode->fid.vid, dvnode->fid.vnode, dentry, mode);
1667
1668	if (dentry->d_name.len >= AFSNAMEMAX)
1669		goto error;
1670
1671	op = afs_alloc_operation(NULL, dvnode->volume);
1672	if (IS_ERR(op)) {
1673		ret = PTR_ERR(op);
1674		goto error;
1675	}
1676
1677	afs_op_set_vnode(op, 0, dvnode);
1678	op->file[0].dv_delta = 1;
1679	op->file[0].modification = true;
1680	op->file[0].update_ctime = true;
1681
1682	op->dentry	= dentry;
1683	op->create.mode	= S_IFREG | mode;
1684	op->create.reason = afs_edit_dir_for_create;
1685	op->mtime	= current_time(dir);
1686	op->ops		= &afs_create_operation;
1687	return afs_do_sync_operation(op);
1688
1689error:
1690	d_drop(dentry);
1691	_leave(" = %d", ret);
1692	return ret;
1693}
1694
1695static void afs_link_success(struct afs_operation *op)
1696{
1697	struct afs_vnode_param *dvp = &op->file[0];
1698	struct afs_vnode_param *vp = &op->file[1];
1699
1700	_enter("op=%08x", op->debug_id);
1701	op->ctime = dvp->scb.status.mtime_client;
1702	afs_vnode_commit_status(op, dvp);
1703	afs_vnode_commit_status(op, vp);
1704	afs_update_dentry_version(op, dvp, op->dentry);
1705	if (op->dentry_2->d_parent == op->dentry->d_parent)
1706		afs_update_dentry_version(op, dvp, op->dentry_2);
1707	ihold(&vp->vnode->netfs.inode);
1708	d_instantiate(op->dentry, &vp->vnode->netfs.inode);
1709}
1710
1711static void afs_link_put(struct afs_operation *op)
1712{
1713	_enter("op=%08x", op->debug_id);
1714	if (afs_op_error(op))
1715		d_drop(op->dentry);
1716}
1717
1718static const struct afs_operation_ops afs_link_operation = {
1719	.issue_afs_rpc	= afs_fs_link,
1720	.issue_yfs_rpc	= yfs_fs_link,
1721	.success	= afs_link_success,
1722	.aborted	= afs_check_for_remote_deletion,
1723	.edit_dir	= afs_create_edit_dir,
1724	.put		= afs_link_put,
1725};
1726
1727/*
1728 * create a hard link between files in an AFS filesystem
1729 */
1730static int afs_link(struct dentry *from, struct inode *dir,
1731		    struct dentry *dentry)
1732{
1733	struct afs_operation *op;
1734	struct afs_vnode *dvnode = AFS_FS_I(dir);
1735	struct afs_vnode *vnode = AFS_FS_I(d_inode(from));
1736	int ret = -ENAMETOOLONG;
1737
1738	_enter("{%llx:%llu},{%llx:%llu},{%pd}",
1739	       vnode->fid.vid, vnode->fid.vnode,
1740	       dvnode->fid.vid, dvnode->fid.vnode,
1741	       dentry);
1742
1743	if (dentry->d_name.len >= AFSNAMEMAX)
1744		goto error;
1745
1746	op = afs_alloc_operation(NULL, dvnode->volume);
1747	if (IS_ERR(op)) {
1748		ret = PTR_ERR(op);
1749		goto error;
1750	}
1751
1752	ret = afs_validate(vnode, op->key);
1753	if (ret < 0)
1754		goto error_op;
1755
1756	afs_op_set_vnode(op, 0, dvnode);
1757	afs_op_set_vnode(op, 1, vnode);
1758	op->file[0].dv_delta = 1;
1759	op->file[0].modification = true;
1760	op->file[0].update_ctime = true;
1761	op->file[1].update_ctime = true;
1762
1763	op->dentry		= dentry;
1764	op->dentry_2		= from;
1765	op->ops			= &afs_link_operation;
1766	op->create.reason	= afs_edit_dir_for_link;
1767	return afs_do_sync_operation(op);
1768
1769error_op:
1770	afs_put_operation(op);
1771error:
1772	d_drop(dentry);
1773	_leave(" = %d", ret);
1774	return ret;
1775}
1776
1777static const struct afs_operation_ops afs_symlink_operation = {
1778	.issue_afs_rpc	= afs_fs_symlink,
1779	.issue_yfs_rpc	= yfs_fs_symlink,
1780	.success	= afs_create_success,
1781	.aborted	= afs_check_for_remote_deletion,
1782	.edit_dir	= afs_create_edit_dir,
1783	.put		= afs_create_put,
1784};
1785
1786/*
1787 * create a symlink in an AFS filesystem
1788 */
1789static int afs_symlink(struct mnt_idmap *idmap, struct inode *dir,
1790		       struct dentry *dentry, const char *content)
1791{
1792	struct afs_operation *op;
1793	struct afs_vnode *dvnode = AFS_FS_I(dir);
1794	int ret;
1795
1796	_enter("{%llx:%llu},{%pd},%s",
1797	       dvnode->fid.vid, dvnode->fid.vnode, dentry,
1798	       content);
1799
1800	ret = -ENAMETOOLONG;
1801	if (dentry->d_name.len >= AFSNAMEMAX)
1802		goto error;
1803
1804	ret = -EINVAL;
1805	if (strlen(content) >= AFSPATHMAX)
1806		goto error;
1807
1808	op = afs_alloc_operation(NULL, dvnode->volume);
1809	if (IS_ERR(op)) {
1810		ret = PTR_ERR(op);
1811		goto error;
1812	}
1813
1814	afs_op_set_vnode(op, 0, dvnode);
1815	op->file[0].dv_delta = 1;
1816
1817	op->dentry		= dentry;
1818	op->ops			= &afs_symlink_operation;
1819	op->create.reason	= afs_edit_dir_for_symlink;
1820	op->create.symlink	= content;
1821	op->mtime		= current_time(dir);
1822	return afs_do_sync_operation(op);
1823
1824error:
1825	d_drop(dentry);
1826	_leave(" = %d", ret);
1827	return ret;
1828}
1829
1830static void afs_rename_success(struct afs_operation *op)
1831{
1832	struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
1833
1834	_enter("op=%08x", op->debug_id);
1835
1836	op->ctime = op->file[0].scb.status.mtime_client;
1837	afs_check_dir_conflict(op, &op->file[1]);
1838	afs_vnode_commit_status(op, &op->file[0]);
1839	if (op->file[1].vnode != op->file[0].vnode) {
1840		op->ctime = op->file[1].scb.status.mtime_client;
1841		afs_vnode_commit_status(op, &op->file[1]);
1842	}
1843
1844	/* If we're moving a subdir between dirs, we need to update
1845	 * its DV counter too as the ".." will be altered.
1846	 */
1847	if (S_ISDIR(vnode->netfs.inode.i_mode) &&
1848	    op->file[0].vnode != op->file[1].vnode) {
1849		u64 new_dv;
1850
1851		write_seqlock(&vnode->cb_lock);
1852
1853		new_dv = vnode->status.data_version + 1;
1854		vnode->status.data_version = new_dv;
1855		inode_set_iversion_raw(&vnode->netfs.inode, new_dv);
1856
1857		write_sequnlock(&vnode->cb_lock);
1858	}
1859}
1860
1861static void afs_rename_edit_dir(struct afs_operation *op)
1862{
1863	struct afs_vnode_param *orig_dvp = &op->file[0];
1864	struct afs_vnode_param *new_dvp = &op->file[1];
1865	struct afs_vnode *orig_dvnode = orig_dvp->vnode;
1866	struct afs_vnode *new_dvnode = new_dvp->vnode;
1867	struct afs_vnode *vnode = AFS_FS_I(d_inode(op->dentry));
1868	struct dentry *old_dentry = op->dentry;
1869	struct dentry *new_dentry = op->dentry_2;
1870	struct inode *new_inode;
1871
1872	_enter("op=%08x", op->debug_id);
1873
1874	if (op->rename.rehash) {
1875		d_rehash(op->rename.rehash);
1876		op->rename.rehash = NULL;
1877	}
1878
1879	down_write(&orig_dvnode->validate_lock);
1880	if (test_bit(AFS_VNODE_DIR_VALID, &orig_dvnode->flags) &&
1881	    orig_dvnode->status.data_version == orig_dvp->dv_before + orig_dvp->dv_delta)
1882		afs_edit_dir_remove(orig_dvnode, &old_dentry->d_name,
1883				    afs_edit_dir_for_rename_0);
1884
1885	if (new_dvnode != orig_dvnode) {
1886		up_write(&orig_dvnode->validate_lock);
1887		down_write(&new_dvnode->validate_lock);
1888	}
1889
1890	if (test_bit(AFS_VNODE_DIR_VALID, &new_dvnode->flags) &&
1891	    new_dvnode->status.data_version == new_dvp->dv_before + new_dvp->dv_delta) {
1892		if (!op->rename.new_negative)
1893			afs_edit_dir_remove(new_dvnode, &new_dentry->d_name,
1894					    afs_edit_dir_for_rename_1);
1895
1896		afs_edit_dir_add(new_dvnode, &new_dentry->d_name,
1897				 &vnode->fid, afs_edit_dir_for_rename_2);
1898	}
1899
1900	if (S_ISDIR(vnode->netfs.inode.i_mode) &&
1901	    new_dvnode != orig_dvnode &&
1902	    test_bit(AFS_VNODE_DIR_VALID, &vnode->flags))
1903		afs_edit_dir_update_dotdot(vnode, new_dvnode,
1904					   afs_edit_dir_for_rename_sub);
1905
1906	new_inode = d_inode(new_dentry);
1907	if (new_inode) {
1908		spin_lock(&new_inode->i_lock);
1909		if (S_ISDIR(new_inode->i_mode))
1910			clear_nlink(new_inode);
1911		else if (new_inode->i_nlink > 0)
1912			drop_nlink(new_inode);
1913		spin_unlock(&new_inode->i_lock);
1914	}
1915
1916	/* Now we can update d_fsdata on the dentries to reflect their
1917	 * new parent's data_version.
1918	 *
1919	 * Note that if we ever implement RENAME_EXCHANGE, we'll have
1920	 * to update both dentries with opposing dir versions.
1921	 */
1922	afs_update_dentry_version(op, new_dvp, op->dentry);
1923	afs_update_dentry_version(op, new_dvp, op->dentry_2);
1924
1925	d_move(old_dentry, new_dentry);
1926
1927	up_write(&new_dvnode->validate_lock);
1928}
1929
1930static void afs_rename_put(struct afs_operation *op)
1931{
1932	_enter("op=%08x", op->debug_id);
1933	if (op->rename.rehash)
1934		d_rehash(op->rename.rehash);
1935	dput(op->rename.tmp);
1936	if (afs_op_error(op))
1937		d_rehash(op->dentry);
1938}
1939
1940static const struct afs_operation_ops afs_rename_operation = {
1941	.issue_afs_rpc	= afs_fs_rename,
1942	.issue_yfs_rpc	= yfs_fs_rename,
1943	.success	= afs_rename_success,
1944	.edit_dir	= afs_rename_edit_dir,
1945	.put		= afs_rename_put,
1946};
1947
1948/*
1949 * rename a file in an AFS filesystem and/or move it between directories
1950 */
1951static int afs_rename(struct mnt_idmap *idmap, struct inode *old_dir,
1952		      struct dentry *old_dentry, struct inode *new_dir,
1953		      struct dentry *new_dentry, unsigned int flags)
1954{
1955	struct afs_operation *op;
1956	struct afs_vnode *orig_dvnode, *new_dvnode, *vnode;
1957	int ret;
1958
1959	if (flags)
1960		return -EINVAL;
1961
1962	/* Don't allow silly-rename files be moved around. */
1963	if (old_dentry->d_flags & DCACHE_NFSFS_RENAMED)
1964		return -EINVAL;
1965
1966	vnode = AFS_FS_I(d_inode(old_dentry));
1967	orig_dvnode = AFS_FS_I(old_dir);
1968	new_dvnode = AFS_FS_I(new_dir);
1969
1970	_enter("{%llx:%llu},{%llx:%llu},{%llx:%llu},{%pd}",
1971	       orig_dvnode->fid.vid, orig_dvnode->fid.vnode,
1972	       vnode->fid.vid, vnode->fid.vnode,
1973	       new_dvnode->fid.vid, new_dvnode->fid.vnode,
1974	       new_dentry);
1975
1976	op = afs_alloc_operation(NULL, orig_dvnode->volume);
1977	if (IS_ERR(op))
1978		return PTR_ERR(op);
1979
1980	ret = afs_validate(vnode, op->key);
1981	afs_op_set_error(op, ret);
1982	if (ret < 0)
1983		goto error;
1984
1985	afs_op_set_vnode(op, 0, orig_dvnode);
1986	afs_op_set_vnode(op, 1, new_dvnode); /* May be same as orig_dvnode */
1987	op->file[0].dv_delta = 1;
1988	op->file[1].dv_delta = 1;
1989	op->file[0].modification = true;
1990	op->file[1].modification = true;
1991	op->file[0].update_ctime = true;
1992	op->file[1].update_ctime = true;
1993
1994	op->dentry		= old_dentry;
1995	op->dentry_2		= new_dentry;
1996	op->rename.new_negative	= d_is_negative(new_dentry);
1997	op->ops			= &afs_rename_operation;
1998
1999	/* For non-directories, check whether the target is busy and if so,
2000	 * make a copy of the dentry and then do a silly-rename.  If the
2001	 * silly-rename succeeds, the copied dentry is hashed and becomes the
2002	 * new target.
2003	 */
2004	if (d_is_positive(new_dentry) && !d_is_dir(new_dentry)) {
2005		/* To prevent any new references to the target during the
2006		 * rename, we unhash the dentry in advance.
2007		 */
2008		if (!d_unhashed(new_dentry)) {
2009			d_drop(new_dentry);
2010			op->rename.rehash = new_dentry;
2011		}
2012
2013		if (d_count(new_dentry) > 2) {
2014			/* copy the target dentry's name */
2015			op->rename.tmp = d_alloc(new_dentry->d_parent,
2016						 &new_dentry->d_name);
2017			if (!op->rename.tmp) {
2018				afs_op_nomem(op);
2019				goto error;
2020			}
2021
2022			ret = afs_sillyrename(new_dvnode,
2023					      AFS_FS_I(d_inode(new_dentry)),
2024					      new_dentry, op->key);
2025			if (ret) {
2026				afs_op_set_error(op, ret);
2027				goto error;
2028			}
2029
2030			op->dentry_2 = op->rename.tmp;
2031			op->rename.rehash = NULL;
2032			op->rename.new_negative = true;
2033		}
2034	}
2035
2036	/* This bit is potentially nasty as there's a potential race with
2037	 * afs_d_revalidate{,_rcu}().  We have to change d_fsdata on the dentry
2038	 * to reflect it's new parent's new data_version after the op, but
2039	 * d_revalidate may see old_dentry between the op having taken place
2040	 * and the version being updated.
2041	 *
2042	 * So drop the old_dentry for now to make other threads go through
2043	 * lookup instead - which we hold a lock against.
2044	 */
2045	d_drop(old_dentry);
2046
2047	return afs_do_sync_operation(op);
2048
2049error:
2050	return afs_put_operation(op);
2051}
2052
2053/*
2054 * Release a directory folio and clean up its private state if it's not busy
2055 * - return true if the folio can now be released, false if not
2056 */
2057static bool afs_dir_release_folio(struct folio *folio, gfp_t gfp_flags)
2058{
2059	struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
2060
2061	_enter("{{%llx:%llu}[%lu]}", dvnode->fid.vid, dvnode->fid.vnode, folio->index);
2062
2063	folio_detach_private(folio);
2064
2065	/* The directory will need reloading. */
2066	if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2067		afs_stat_v(dvnode, n_relpg);
2068	return true;
2069}
2070
2071/*
2072 * Invalidate part or all of a folio.
2073 */
2074static void afs_dir_invalidate_folio(struct folio *folio, size_t offset,
2075				   size_t length)
2076{
2077	struct afs_vnode *dvnode = AFS_FS_I(folio_inode(folio));
2078
2079	_enter("{%lu},%zu,%zu", folio->index, offset, length);
2080
2081	BUG_ON(!folio_test_locked(folio));
2082
2083	/* The directory will need reloading. */
2084	if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &dvnode->flags))
2085		afs_stat_v(dvnode, n_inval);
2086
2087	/* we clean up only if the entire folio is being invalidated */
2088	if (offset == 0 && length == folio_size(folio))
2089		folio_detach_private(folio);
2090}