1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/ceph/ceph_debug.h>
   3
   4#include <linux/spinlock.h>
 
   5#include <linux/namei.h>
   6#include <linux/slab.h>
   7#include <linux/sched.h>
   8#include <linux/xattr.h>
   9
  10#include "super.h"
  11#include "mds_client.h"
  12
  13/*
  14 * Directory operations: readdir, lookup, create, link, unlink,
  15 * rename, etc.
  16 */
  17
  18/*
  19 * Ceph MDS operations are specified in terms of a base ino and
  20 * relative path.  Thus, the client can specify an operation on a
  21 * specific inode (e.g., a getattr due to fstat(2)), or as a path
  22 * relative to, say, the root directory.
  23 *
  24 * Normally, we limit ourselves to strict inode ops (no path component)
  25 * or dentry operations (a single path component relative to an ino).  The
  26 * exception to this is open_root_dentry(), which will open the mount
  27 * point by name.
  28 */
  29
 
 
  30const struct dentry_operations ceph_dentry_ops;
  31
  32static bool __dentry_lease_is_valid(struct ceph_dentry_info *di);
  33static int __dir_lease_try_check(const struct dentry *dentry);
  34
  35/*
  36 * Initialize ceph dentry state.
  37 */
  38static int ceph_d_init(struct dentry *dentry)
  39{
  40	struct ceph_dentry_info *di;
  41	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
  42	struct ceph_mds_client *mdsc = fsc->mdsc;
  43
  44	di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
 
 
 
  45	if (!di)
  46		return -ENOMEM;          /* oh well */
  47
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  48	di->dentry = dentry;
  49	di->lease_session = NULL;
  50	di->time = jiffies;
 
 
  51	dentry->d_fsdata = di;
  52	INIT_LIST_HEAD(&di->lease_list);
  53
  54	atomic64_inc(&mdsc->metric.total_dentries);
  55
  56	return 0;
  57}
  58
  59/*
  60 * for f_pos for readdir:
  61 * - hash order:
  62 *	(0xff << 52) | ((24 bits hash) << 28) |
  63 *	(the nth entry has hash collision);
  64 * - frag+name order;
  65 *	((frag value) << 28) | (the nth entry in frag);
  66 */
  67#define OFFSET_BITS	28
  68#define OFFSET_MASK	((1 << OFFSET_BITS) - 1)
  69#define HASH_ORDER	(0xffull << (OFFSET_BITS + 24))
  70loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
  71{
  72	loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
  73	if (hash_order)
  74		fpos |= HASH_ORDER;
  75	return fpos;
  76}
  77
  78static bool is_hash_order(loff_t p)
  79{
  80	return (p & HASH_ORDER) == HASH_ORDER;
  81}
  82
  83static unsigned fpos_frag(loff_t p)
  84{
  85	return p >> OFFSET_BITS;
  86}
  87
  88static unsigned fpos_hash(loff_t p)
  89{
  90	return ceph_frag_value(fpos_frag(p));
  91}
  92
  93static unsigned fpos_off(loff_t p)
  94{
  95	return p & OFFSET_MASK;
 
 
 
 
  96}
  97
  98static int fpos_cmp(loff_t l, loff_t r)
  99{
 100	int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
 101	if (v)
 102		return v;
 103	return (int)(fpos_off(l) - fpos_off(r));
 104}
 105
 106/*
 107 * make note of the last dentry we read, so we can
 108 * continue at the same lexicographical point,
 109 * regardless of what dir changes take place on the
 110 * server.
 111 */
 112static int note_last_dentry(struct ceph_dir_file_info *dfi, const char *name,
 113		            int len, unsigned next_offset)
 114{
 115	char *buf = kmalloc(len+1, GFP_KERNEL);
 116	if (!buf)
 117		return -ENOMEM;
 118	kfree(dfi->last_name);
 119	dfi->last_name = buf;
 120	memcpy(dfi->last_name, name, len);
 121	dfi->last_name[len] = 0;
 122	dfi->next_offset = next_offset;
 123	dout("note_last_dentry '%s'\n", dfi->last_name);
 124	return 0;
 125}
 126
 127
 128static struct dentry *
 129__dcache_find_get_entry(struct dentry *parent, u64 idx,
 130			struct ceph_readdir_cache_control *cache_ctl)
 131{
 132	struct inode *dir = d_inode(parent);
 133	struct dentry *dentry;
 134	unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
 135	loff_t ptr_pos = idx * sizeof(struct dentry *);
 136	pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
 137
 138	if (ptr_pos >= i_size_read(dir))
 139		return NULL;
 140
 141	if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) {
 142		ceph_readdir_cache_release(cache_ctl);
 143		cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
 144		if (!cache_ctl->page) {
 145			dout(" page %lu not found\n", ptr_pgoff);
 146			return ERR_PTR(-EAGAIN);
 147		}
 148		/* reading/filling the cache are serialized by
 149		   i_mutex, no need to use page lock */
 150		unlock_page(cache_ctl->page);
 151		cache_ctl->dentries = kmap(cache_ctl->page);
 152	}
 153
 154	cache_ctl->index = idx & idx_mask;
 155
 156	rcu_read_lock();
 157	spin_lock(&parent->d_lock);
 158	/* check i_size again here, because empty directory can be
 159	 * marked as complete while not holding the i_mutex. */
 160	if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
 161		dentry = cache_ctl->dentries[cache_ctl->index];
 162	else
 163		dentry = NULL;
 164	spin_unlock(&parent->d_lock);
 165	if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
 166		dentry = NULL;
 167	rcu_read_unlock();
 168	return dentry ? : ERR_PTR(-EAGAIN);
 169}
 170
 171/*
 172 * When possible, we try to satisfy a readdir by peeking at the
 173 * dcache.  We make this work by carefully ordering dentries on
 174 * d_child when we initially get results back from the MDS, and
 175 * falling back to a "normal" sync readdir if any dentries in the dir
 176 * are dropped.
 177 *
 178 * Complete dir indicates that we have all dentries in the dir.  It is
 179 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
 180 * the MDS if/when the directory is modified).
 181 */
 182static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 183			    int shared_gen)
 184{
 185	struct ceph_dir_file_info *dfi = file->private_data;
 186	struct dentry *parent = file->f_path.dentry;
 187	struct inode *dir = d_inode(parent);
 188	struct dentry *dentry, *last = NULL;
 
 189	struct ceph_dentry_info *di;
 190	struct ceph_readdir_cache_control cache_ctl = {};
 191	u64 idx = 0;
 192	int err = 0;
 193
 194	dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
 
 
 195
 196	/* search start position */
 197	if (ctx->pos > 2) {
 198		u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
 199		while (count > 0) {
 200			u64 step = count >> 1;
 201			dentry = __dcache_find_get_entry(parent, idx + step,
 202							 &cache_ctl);
 203			if (!dentry) {
 204				/* use linar search */
 205				idx = 0;
 206				break;
 207			}
 208			if (IS_ERR(dentry)) {
 209				err = PTR_ERR(dentry);
 210				goto out;
 211			}
 212			di = ceph_dentry(dentry);
 213			spin_lock(&dentry->d_lock);
 214			if (fpos_cmp(di->offset, ctx->pos) < 0) {
 215				idx += step + 1;
 216				count -= step + 1;
 217			} else {
 218				count = step;
 219			}
 220			spin_unlock(&dentry->d_lock);
 221			dput(dentry);
 222		}
 223
 224		dout("__dcache_readdir %p cache idx %llu\n", dir, idx);
 225	}
 226
 
 
 
 
 
 
 
 
 
 
 227
 228	for (;;) {
 229		bool emit_dentry = false;
 230		dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
 231		if (!dentry) {
 232			dfi->file_info.flags |= CEPH_F_ATEND;
 233			err = 0;
 
 
 
 
 
 
 
 
 
 
 234			break;
 235		}
 236		if (IS_ERR(dentry)) {
 237			err = PTR_ERR(dentry);
 238			goto out;
 239		}
 240
 241		spin_lock(&dentry->d_lock);
 242		di = ceph_dentry(dentry);
 243		if (d_unhashed(dentry) ||
 244		    d_really_is_negative(dentry) ||
 245		    di->lease_shared_gen != shared_gen) {
 246			spin_unlock(&dentry->d_lock);
 247			dput(dentry);
 248			err = -EAGAIN;
 249			goto out;
 250		}
 251		if (fpos_cmp(ctx->pos, di->offset) <= 0) {
 252			__ceph_dentry_dir_lease_touch(di);
 253			emit_dentry = true;
 254		}
 255		spin_unlock(&dentry->d_lock);
 
 
 
 
 256
 257		if (emit_dentry) {
 258			dout(" %llx dentry %p %pd %p\n", di->offset,
 259			     dentry, dentry, d_inode(dentry));
 260			ctx->pos = di->offset;
 261			if (!dir_emit(ctx, dentry->d_name.name,
 262				      dentry->d_name.len, ceph_present_inode(d_inode(dentry)),
 263				      d_inode(dentry)->i_mode >> 12)) {
 264				dput(dentry);
 265				err = 0;
 266				break;
 267			}
 268			ctx->pos++;
 269
 270			if (last)
 271				dput(last);
 272			last = dentry;
 
 
 273		} else {
 274			dput(dentry);
 275		}
 276	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 277out:
 278	ceph_readdir_cache_release(&cache_ctl);
 279	if (last) {
 280		int ret;
 281		di = ceph_dentry(last);
 282		ret = note_last_dentry(dfi, last->d_name.name, last->d_name.len,
 283				       fpos_off(di->offset) + 1);
 284		if (ret < 0)
 285			err = ret;
 286		dput(last);
 287		/* last_name no longer match cache index */
 288		if (dfi->readdir_cache_idx >= 0) {
 289			dfi->readdir_cache_idx = -1;
 290			dfi->dir_release_count = 0;
 291		}
 292	}
 293	return err;
 294}
 295
 296static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
 
 
 
 
 
 
 
 297{
 298	if (!dfi->last_readdir)
 299		return true;
 300	if (is_hash_order(pos))
 301		return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
 302	else
 303		return dfi->frag != fpos_frag(pos);
 
 
 304}
 305
 306static int ceph_readdir(struct file *file, struct dir_context *ctx)
 307{
 308	struct ceph_dir_file_info *dfi = file->private_data;
 309	struct inode *inode = file_inode(file);
 310	struct ceph_inode_info *ci = ceph_inode(inode);
 311	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 312	struct ceph_mds_client *mdsc = fsc->mdsc;
 313	int i;
 
 314	int err;
 315	unsigned frag = -1;
 316	struct ceph_mds_reply_info_parsed *rinfo;
 
 
 317
 318	dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
 319	if (dfi->file_info.flags & CEPH_F_ATEND)
 320		return 0;
 321
 322	/* always start with . and .. */
 323	if (ctx->pos == 0) {
 
 
 
 
 324		dout("readdir off 0 -> '.'\n");
 325		if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode),
 326			    inode->i_mode >> 12))
 
 327			return 0;
 328		ctx->pos = 1;
 
 329	}
 330	if (ctx->pos == 1) {
 331		u64 ino;
 332		struct dentry *dentry = file->f_path.dentry;
 333
 334		spin_lock(&dentry->d_lock);
 335		ino = ceph_present_inode(dentry->d_parent->d_inode);
 336		spin_unlock(&dentry->d_lock);
 337
 338		dout("readdir off 1 -> '..'\n");
 339		if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12))
 
 
 340			return 0;
 341		ctx->pos = 2;
 
 342	}
 343
 344	spin_lock(&ci->i_ceph_lock);
 345	/* request Fx cap. if have Fx, we don't need to release Fs cap
 346	 * for later create/unlink. */
 347	__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR);
 348	/* can we use the dcache? */
 349	if (ceph_test_mount_opt(fsc, DCACHE) &&
 
 350	    !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
 351	    ceph_snap(inode) != CEPH_SNAPDIR &&
 352	    __ceph_dir_is_complete_ordered(ci) &&
 353	    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
 354		int shared_gen = atomic_read(&ci->i_shared_gen);
 355
 356		spin_unlock(&ci->i_ceph_lock);
 357		err = __dcache_readdir(file, ctx, shared_gen);
 358		if (err != -EAGAIN)
 359			return err;
 360	} else {
 361		spin_unlock(&ci->i_ceph_lock);
 
 
 
 
 
 
 
 
 362	}
 363
 364	/* proceed with a normal readdir */
 
 365more:
 366	/* do we have the correct frag content buffered? */
 367	if (need_send_readdir(dfi, ctx->pos)) {
 368		struct ceph_mds_request *req;
 369		int op = ceph_snap(inode) == CEPH_SNAPDIR ?
 370			CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
 371
 372		/* discard old result, if any */
 373		if (dfi->last_readdir) {
 374			ceph_mdsc_put_request(dfi->last_readdir);
 375			dfi->last_readdir = NULL;
 376		}
 377
 378		if (is_hash_order(ctx->pos)) {
 379			/* fragtree isn't always accurate. choose frag
 380			 * based on previous reply when possible. */
 381			if (frag == (unsigned)-1)
 382				frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
 383							NULL, NULL);
 384		} else {
 385			frag = fpos_frag(ctx->pos);
 386		}
 387
 388		dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
 389		     ceph_vinop(inode), frag, dfi->last_name);
 390		req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 391		if (IS_ERR(req))
 392			return PTR_ERR(req);
 393		err = ceph_alloc_readdir_reply_buffer(req, inode);
 394		if (err) {
 395			ceph_mdsc_put_request(req);
 396			return err;
 397		}
 398		/* hints to request -> mds selection code */
 399		req->r_direct_mode = USE_AUTH_MDS;
 400		if (op == CEPH_MDS_OP_READDIR) {
 401			req->r_direct_hash = ceph_frag_value(frag);
 402			__set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
 403			req->r_inode_drop = CEPH_CAP_FILE_EXCL;
 404		}
 405		if (dfi->last_name) {
 406			req->r_path2 = kstrdup(dfi->last_name, GFP_KERNEL);
 407			if (!req->r_path2) {
 408				ceph_mdsc_put_request(req);
 409				return -ENOMEM;
 410			}
 411		} else if (is_hash_order(ctx->pos)) {
 412			req->r_args.readdir.offset_hash =
 413				cpu_to_le32(fpos_hash(ctx->pos));
 414		}
 415
 416		req->r_dir_release_cnt = dfi->dir_release_count;
 417		req->r_dir_ordered_cnt = dfi->dir_ordered_count;
 418		req->r_readdir_cache_idx = dfi->readdir_cache_idx;
 419		req->r_readdir_offset = dfi->next_offset;
 420		req->r_args.readdir.frag = cpu_to_le32(frag);
 421		req->r_args.readdir.flags =
 422				cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
 423
 424		req->r_inode = inode;
 425		ihold(inode);
 426		req->r_dentry = dget(file->f_path.dentry);
 427		err = ceph_mdsc_do_request(mdsc, NULL, req);
 428		if (err < 0) {
 429			ceph_mdsc_put_request(req);
 430			return err;
 431		}
 432		dout("readdir got and parsed readdir result=%d on "
 433		     "frag %x, end=%d, complete=%d, hash_order=%d\n",
 434		     err, frag,
 435		     (int)req->r_reply_info.dir_end,
 436		     (int)req->r_reply_info.dir_complete,
 437		     (int)req->r_reply_info.hash_order);
 438
 439		rinfo = &req->r_reply_info;
 440		if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
 441			frag = le32_to_cpu(rinfo->dir_dir->frag);
 442			if (!rinfo->hash_order) {
 443				dfi->next_offset = req->r_readdir_offset;
 444				/* adjust ctx->pos to beginning of frag */
 445				ctx->pos = ceph_make_fpos(frag,
 446							  dfi->next_offset,
 447							  false);
 448			}
 449		}
 450
 451		dfi->frag = frag;
 452		dfi->last_readdir = req;
 
 453
 454		if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
 455			dfi->readdir_cache_idx = req->r_readdir_cache_idx;
 456			if (dfi->readdir_cache_idx < 0) {
 457				/* preclude from marking dir ordered */
 458				dfi->dir_ordered_count = 0;
 459			} else if (ceph_frag_is_leftmost(frag) &&
 460				   dfi->next_offset == 2) {
 461				/* note dir version at start of readdir so
 462				 * we can tell if any dentries get dropped */
 463				dfi->dir_release_count = req->r_dir_release_cnt;
 464				dfi->dir_ordered_count = req->r_dir_ordered_cnt;
 465			}
 466		} else {
 467			dout("readdir !did_prepopulate\n");
 468			/* disable readdir cache */
 469			dfi->readdir_cache_idx = -1;
 470			/* preclude from marking dir complete */
 471			dfi->dir_release_count = 0;
 472		}
 473
 474		/* note next offset and last dentry name */
 475		if (rinfo->dir_nr > 0) {
 476			struct ceph_mds_reply_dir_entry *rde =
 477					rinfo->dir_entries + (rinfo->dir_nr-1);
 478			unsigned next_offset = req->r_reply_info.dir_end ?
 479					2 : (fpos_off(rde->offset) + 1);
 480			err = note_last_dentry(dfi, rde->name, rde->name_len,
 481					       next_offset);
 482			if (err)
 483				return err;
 484		} else if (req->r_reply_info.dir_end) {
 485			dfi->next_offset = 2;
 486			/* keep last name */
 487		}
 488	}
 489
 490	rinfo = &dfi->last_readdir->r_reply_info;
 491	dout("readdir frag %x num %d pos %llx chunk first %llx\n",
 492	     dfi->frag, rinfo->dir_nr, ctx->pos,
 493	     rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
 494
 495	i = 0;
 496	/* search start position */
 497	if (rinfo->dir_nr > 0) {
 498		int step, nr = rinfo->dir_nr;
 499		while (nr > 0) {
 500			step = nr >> 1;
 501			if (rinfo->dir_entries[i + step].offset < ctx->pos) {
 502				i +=  step + 1;
 503				nr -= step + 1;
 504			} else {
 505				nr = step;
 506			}
 507		}
 508	}
 509	for (; i < rinfo->dir_nr; i++) {
 510		struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
 511
 512		BUG_ON(rde->offset < ctx->pos);
 513
 514		ctx->pos = rde->offset;
 515		dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
 516		     i, rinfo->dir_nr, ctx->pos,
 517		     rde->name_len, rde->name, &rde->inode.in);
 518
 519		BUG_ON(!rde->inode.in);
 520
 521		if (!dir_emit(ctx, rde->name, rde->name_len,
 522			      ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
 523			      le32_to_cpu(rde->inode.in->mode) >> 12)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 524			dout("filldir stopping us...\n");
 525			return 0;
 526		}
 527		ctx->pos++;
 
 528	}
 529
 530	ceph_mdsc_put_request(dfi->last_readdir);
 531	dfi->last_readdir = NULL;
 532
 533	if (dfi->next_offset > 2) {
 534		frag = dfi->frag;
 535		goto more;
 536	}
 537
 538	/* more frags? */
 539	if (!ceph_frag_is_rightmost(dfi->frag)) {
 540		frag = ceph_frag_next(dfi->frag);
 541		if (is_hash_order(ctx->pos)) {
 542			loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
 543							dfi->next_offset, true);
 544			if (new_pos > ctx->pos)
 545				ctx->pos = new_pos;
 546			/* keep last_name */
 547		} else {
 548			ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
 549							false);
 550			kfree(dfi->last_name);
 551			dfi->last_name = NULL;
 552		}
 553		dout("readdir next frag is %x\n", frag);
 554		goto more;
 555	}
 556	dfi->file_info.flags |= CEPH_F_ATEND;
 557
 558	/*
 559	 * if dir_release_count still matches the dir, no dentries
 560	 * were released during the whole readdir, and we should have
 561	 * the complete dir contents in our cache.
 562	 */
 563	if (atomic64_read(&ci->i_release_count) ==
 564					dfi->dir_release_count) {
 565		spin_lock(&ci->i_ceph_lock);
 566		if (dfi->dir_ordered_count ==
 567				atomic64_read(&ci->i_ordered_count)) {
 568			dout(" marking %p complete and ordered\n", inode);
 569			/* use i_size to track number of entries in
 570			 * readdir cache */
 571			BUG_ON(dfi->readdir_cache_idx < 0);
 572			i_size_write(inode, dfi->readdir_cache_idx *
 573				     sizeof(struct dentry*));
 574		} else {
 575			dout(" marking %p complete\n", inode);
 576		}
 577		__ceph_dir_set_complete(ci, dfi->dir_release_count,
 578					dfi->dir_ordered_count);
 579		spin_unlock(&ci->i_ceph_lock);
 580	}
 
 581
 582	dout("readdir %p file %p done.\n", inode, file);
 583	return 0;
 584}
 585
 586static void reset_readdir(struct ceph_dir_file_info *dfi)
 587{
 588	if (dfi->last_readdir) {
 589		ceph_mdsc_put_request(dfi->last_readdir);
 590		dfi->last_readdir = NULL;
 591	}
 592	kfree(dfi->last_name);
 593	dfi->last_name = NULL;
 594	dfi->dir_release_count = 0;
 595	dfi->readdir_cache_idx = -1;
 596	dfi->next_offset = 2;  /* compensate for . and .. */
 597	dfi->file_info.flags &= ~CEPH_F_ATEND;
 598}
 599
 600/*
 601 * discard buffered readdir content on seekdir(0), or seek to new frag,
 602 * or seek prior to current chunk
 603 */
 604static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
 605{
 606	struct ceph_mds_reply_info_parsed *rinfo;
 607	loff_t chunk_offset;
 608	if (new_pos == 0)
 609		return true;
 610	if (is_hash_order(new_pos)) {
 611		/* no need to reset last_name for a forward seek when
 612		 * dentries are sotred in hash order */
 613	} else if (dfi->frag != fpos_frag(new_pos)) {
 614		return true;
 615	}
 616	rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
 617	if (!rinfo || !rinfo->dir_nr)
 618		return true;
 619	chunk_offset = rinfo->dir_entries[0].offset;
 620	return new_pos < chunk_offset ||
 621	       is_hash_order(new_pos) != is_hash_order(chunk_offset);
 622}
 623
 624static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 625{
 626	struct ceph_dir_file_info *dfi = file->private_data;
 627	struct inode *inode = file->f_mapping->host;
 
 628	loff_t retval;
 629
 630	inode_lock(inode);
 631	retval = -EINVAL;
 632	switch (whence) {
 
 
 
 633	case SEEK_CUR:
 634		offset += file->f_pos;
 635	case SEEK_SET:
 636		break;
 637	case SEEK_END:
 638		retval = -EOPNOTSUPP;
 639	default:
 640		goto out;
 641	}
 642
 643	if (offset >= 0) {
 644		if (need_reset_readdir(dfi, offset)) {
 645			dout("dir_llseek dropping %p content\n", file);
 646			reset_readdir(dfi);
 647		} else if (is_hash_order(offset) && offset > file->f_pos) {
 648			/* for hash offset, we don't know if a forward seek
 649			 * is within same frag */
 650			dfi->dir_release_count = 0;
 651			dfi->readdir_cache_idx = -1;
 652		}
 653
 654		if (offset != file->f_pos) {
 655			file->f_pos = offset;
 656			file->f_version = 0;
 657			dfi->file_info.flags &= ~CEPH_F_ATEND;
 658		}
 659		retval = offset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 660	}
 661out:
 662	inode_unlock(inode);
 663	return retval;
 664}
 665
 666/*
 667 * Handle lookups for the hidden .snap directory.
 668 */
 669int ceph_handle_snapdir(struct ceph_mds_request *req,
 670			struct dentry *dentry, int err)
 671{
 672	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 673	struct inode *parent = d_inode(dentry->d_parent); /* we hold i_mutex */
 674
 675	/* .snap dir? */
 676	if (err == -ENOENT &&
 677	    ceph_snap(parent) == CEPH_NOSNAP &&
 678	    strcmp(dentry->d_name.name,
 679		   fsc->mount_options->snapdir_name) == 0) {
 680		struct inode *inode = ceph_get_snapdir(parent);
 681		dout("ENOENT on snapdir %p '%pd', linking to snapdir %p\n",
 682		     dentry, dentry, inode);
 683		BUG_ON(!d_unhashed(dentry));
 684		d_add(dentry, inode);
 685		err = 0;
 686	}
 687	return err;
 688}
 689
 690/*
 691 * Figure out final result of a lookup/open request.
 692 *
 693 * Mainly, make sure we return the final req->r_dentry (if it already
 694 * existed) in place of the original VFS-provided dentry when they
 695 * differ.
 696 *
 697 * Gracefully handle the case where the MDS replies with -ENOENT and
 698 * no trace (which it may do, at its discretion, e.g., if it doesn't
 699 * care to issue a lease on the negative dentry).
 700 */
 701struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 702				  struct dentry *dentry, int err)
 703{
 704	if (err == -ENOENT) {
 705		/* no trace? */
 706		err = 0;
 707		if (!req->r_reply_info.head->is_dentry) {
 708			dout("ENOENT and no trace, dentry %p inode %p\n",
 709			     dentry, d_inode(dentry));
 710			if (d_really_is_positive(dentry)) {
 711				d_drop(dentry);
 712				err = -ENOENT;
 713			} else {
 714				d_add(dentry, NULL);
 715			}
 716		}
 717	}
 718	if (err)
 719		dentry = ERR_PTR(err);
 720	else if (dentry != req->r_dentry)
 721		dentry = dget(req->r_dentry);   /* we got spliced */
 722	else
 723		dentry = NULL;
 724	return dentry;
 725}
 726
 727static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
 728{
 729	return ceph_ino(inode) == CEPH_INO_ROOT &&
 730		strncmp(dentry->d_name.name, ".ceph", 5) == 0;
 731}
 732
 733/*
 734 * Look up a single dir entry.  If there is a lookup intent, inform
 735 * the MDS so that it gets our 'caps wanted' value in a single op.
 736 */
 737static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 738				  unsigned int flags)
 739{
 740	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 741	struct ceph_mds_client *mdsc = fsc->mdsc;
 742	struct ceph_mds_request *req;
 743	int op;
 744	int mask;
 745	int err;
 746
 747	dout("lookup %p dentry %p '%pd'\n",
 748	     dir, dentry, dentry);
 749
 750	if (dentry->d_name.len > NAME_MAX)
 751		return ERR_PTR(-ENAMETOOLONG);
 752
 
 
 
 
 
 
 
 
 
 
 
 
 753	/* can we conclude ENOENT locally? */
 754	if (d_really_is_negative(dentry)) {
 755		struct ceph_inode_info *ci = ceph_inode(dir);
 756		struct ceph_dentry_info *di = ceph_dentry(dentry);
 757
 758		spin_lock(&ci->i_ceph_lock);
 759		dout(" dir %p flags are 0x%lx\n", dir, ci->i_ceph_flags);
 760		if (strncmp(dentry->d_name.name,
 761			    fsc->mount_options->snapdir_name,
 762			    dentry->d_name.len) &&
 763		    !is_root_ceph_dentry(dir, dentry) &&
 764		    ceph_test_mount_opt(fsc, DCACHE) &&
 765		    __ceph_dir_is_complete(ci) &&
 766		    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
 767			__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
 768			spin_unlock(&ci->i_ceph_lock);
 769			dout(" dir %p complete, -ENOENT\n", dir);
 770			d_add(dentry, NULL);
 771			di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
 772			return NULL;
 773		}
 774		spin_unlock(&ci->i_ceph_lock);
 775	}
 776
 777	op = ceph_snap(dir) == CEPH_SNAPDIR ?
 778		CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
 779	req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
 780	if (IS_ERR(req))
 781		return ERR_CAST(req);
 782	req->r_dentry = dget(dentry);
 783	req->r_num_caps = 2;
 784
 785	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
 786	if (ceph_security_xattr_wanted(dir))
 787		mask |= CEPH_CAP_XATTR_SHARED;
 788	req->r_args.getattr.mask = cpu_to_le32(mask);
 789
 790	req->r_parent = dir;
 791	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 792	err = ceph_mdsc_do_request(mdsc, NULL, req);
 793	err = ceph_handle_snapdir(req, dentry, err);
 794	dentry = ceph_finish_lookup(req, dentry, err);
 795	ceph_mdsc_put_request(req);  /* will dput(dentry) */
 796	dout("lookup result=%p\n", dentry);
 797	return dentry;
 798}
 799
 800/*
 801 * If we do a create but get no trace back from the MDS, follow up with
 802 * a lookup (the VFS expects us to link up the provided dentry).
 803 */
 804int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
 805{
 806	struct dentry *result = ceph_lookup(dir, dentry, 0);
 807
 808	if (result && !IS_ERR(result)) {
 809		/*
 810		 * We created the item, then did a lookup, and found
 811		 * it was already linked to another inode we already
 812		 * had in our cache (and thus got spliced). To not
 813		 * confuse VFS (especially when inode is a directory),
 814		 * we don't link our dentry to that inode, return an
 815		 * error instead.
 816		 *
 817		 * This event should be rare and it happens only when
 818		 * we talk to old MDS. Recent MDS does not send traceless
 819		 * reply for request that creates new inode.
 820		 */
 821		d_drop(result);
 822		return -ESTALE;
 
 823	}
 824	return PTR_ERR(result);
 825}
 826
 827static int ceph_mknod(struct inode *dir, struct dentry *dentry,
 828		      umode_t mode, dev_t rdev)
 829{
 830	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 831	struct ceph_mds_client *mdsc = fsc->mdsc;
 832	struct ceph_mds_request *req;
 833	struct ceph_acl_sec_ctx as_ctx = {};
 834	int err;
 835
 836	if (ceph_snap(dir) != CEPH_NOSNAP)
 837		return -EROFS;
 838
 839	if (ceph_quota_is_max_files_exceeded(dir)) {
 840		err = -EDQUOT;
 841		goto out;
 842	}
 843
 844	err = ceph_pre_init_acls(dir, &mode, &as_ctx);
 845	if (err < 0)
 846		goto out;
 847	err = ceph_security_init_secctx(dentry, mode, &as_ctx);
 848	if (err < 0)
 849		goto out;
 850
 851	dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
 852	     dir, dentry, mode, rdev);
 853	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
 854	if (IS_ERR(req)) {
 855		err = PTR_ERR(req);
 856		goto out;
 857	}
 858	req->r_dentry = dget(dentry);
 859	req->r_num_caps = 2;
 860	req->r_parent = dir;
 861	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 862	req->r_args.mknod.mode = cpu_to_le32(mode);
 863	req->r_args.mknod.rdev = cpu_to_le32(rdev);
 864	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 865	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 866	if (as_ctx.pagelist) {
 867		req->r_pagelist = as_ctx.pagelist;
 868		as_ctx.pagelist = NULL;
 869	}
 870	err = ceph_mdsc_do_request(mdsc, dir, req);
 871	if (!err && !req->r_reply_info.head->is_dentry)
 872		err = ceph_handle_notrace_create(dir, dentry);
 873	ceph_mdsc_put_request(req);
 874out:
 875	if (!err)
 876		ceph_init_inode_acls(d_inode(dentry), &as_ctx);
 877	else
 878		d_drop(dentry);
 879	ceph_release_acl_sec_ctx(&as_ctx);
 880	return err;
 881}
 882
 883static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 884		       bool excl)
 885{
 886	return ceph_mknod(dir, dentry, mode, 0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 887}
 888
 889static int ceph_symlink(struct inode *dir, struct dentry *dentry,
 890			    const char *dest)
 891{
 892	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 893	struct ceph_mds_client *mdsc = fsc->mdsc;
 894	struct ceph_mds_request *req;
 895	struct ceph_acl_sec_ctx as_ctx = {};
 896	int err;
 897
 898	if (ceph_snap(dir) != CEPH_NOSNAP)
 899		return -EROFS;
 900
 901	if (ceph_quota_is_max_files_exceeded(dir)) {
 902		err = -EDQUOT;
 903		goto out;
 904	}
 905
 906	err = ceph_security_init_secctx(dentry, S_IFLNK | 0777, &as_ctx);
 907	if (err < 0)
 908		goto out;
 909
 910	dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
 911	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
 912	if (IS_ERR(req)) {
 913		err = PTR_ERR(req);
 914		goto out;
 915	}
 916	req->r_path2 = kstrdup(dest, GFP_KERNEL);
 917	if (!req->r_path2) {
 918		err = -ENOMEM;
 919		ceph_mdsc_put_request(req);
 920		goto out;
 921	}
 922	req->r_parent = dir;
 923	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 924	req->r_dentry = dget(dentry);
 925	req->r_num_caps = 2;
 926	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 
 
 927	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 928	if (as_ctx.pagelist) {
 929		req->r_pagelist = as_ctx.pagelist;
 930		as_ctx.pagelist = NULL;
 931	}
 932	err = ceph_mdsc_do_request(mdsc, dir, req);
 933	if (!err && !req->r_reply_info.head->is_dentry)
 934		err = ceph_handle_notrace_create(dir, dentry);
 935	ceph_mdsc_put_request(req);
 936out:
 937	if (err)
 938		d_drop(dentry);
 939	ceph_release_acl_sec_ctx(&as_ctx);
 940	return err;
 941}
 942
 943static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 944{
 945	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 946	struct ceph_mds_client *mdsc = fsc->mdsc;
 947	struct ceph_mds_request *req;
 948	struct ceph_acl_sec_ctx as_ctx = {};
 949	int err = -EROFS;
 950	int op;
 951
 952	if (ceph_snap(dir) == CEPH_SNAPDIR) {
 953		/* mkdir .snap/foo is a MKSNAP */
 954		op = CEPH_MDS_OP_MKSNAP;
 955		dout("mksnap dir %p snap '%pd' dn %p\n", dir,
 956		     dentry, dentry);
 957	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
 958		dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
 959		op = CEPH_MDS_OP_MKDIR;
 960	} else {
 961		goto out;
 962	}
 963
 964	if (op == CEPH_MDS_OP_MKDIR &&
 965	    ceph_quota_is_max_files_exceeded(dir)) {
 966		err = -EDQUOT;
 967		goto out;
 968	}
 969
 970	mode |= S_IFDIR;
 971	err = ceph_pre_init_acls(dir, &mode, &as_ctx);
 972	if (err < 0)
 973		goto out;
 974	err = ceph_security_init_secctx(dentry, mode, &as_ctx);
 975	if (err < 0)
 976		goto out;
 977
 978	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 979	if (IS_ERR(req)) {
 980		err = PTR_ERR(req);
 981		goto out;
 982	}
 983
 984	req->r_dentry = dget(dentry);
 985	req->r_num_caps = 2;
 986	req->r_parent = dir;
 987	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 988	req->r_args.mkdir.mode = cpu_to_le32(mode);
 989	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 990	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 991	if (as_ctx.pagelist) {
 992		req->r_pagelist = as_ctx.pagelist;
 993		as_ctx.pagelist = NULL;
 994	}
 995	err = ceph_mdsc_do_request(mdsc, dir, req);
 996	if (!err &&
 997	    !req->r_reply_info.head->is_target &&
 998	    !req->r_reply_info.head->is_dentry)
 999		err = ceph_handle_notrace_create(dir, dentry);
1000	ceph_mdsc_put_request(req);
1001out:
1002	if (!err)
1003		ceph_init_inode_acls(d_inode(dentry), &as_ctx);
1004	else
1005		d_drop(dentry);
1006	ceph_release_acl_sec_ctx(&as_ctx);
1007	return err;
1008}
1009
1010static int ceph_link(struct dentry *old_dentry, struct inode *dir,
1011		     struct dentry *dentry)
1012{
1013	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1014	struct ceph_mds_client *mdsc = fsc->mdsc;
1015	struct ceph_mds_request *req;
1016	int err;
1017
1018	if (ceph_snap(dir) != CEPH_NOSNAP)
1019		return -EROFS;
1020
1021	dout("link in dir %p old_dentry %p dentry %p\n", dir,
1022	     old_dentry, dentry);
1023	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
1024	if (IS_ERR(req)) {
1025		d_drop(dentry);
1026		return PTR_ERR(req);
1027	}
1028	req->r_dentry = dget(dentry);
1029	req->r_num_caps = 2;
1030	req->r_old_dentry = dget(old_dentry);
1031	req->r_parent = dir;
1032	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1033	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1034	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1035	/* release LINK_SHARED on source inode (mds will lock it) */
1036	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1037	err = ceph_mdsc_do_request(mdsc, dir, req);
1038	if (err) {
1039		d_drop(dentry);
1040	} else if (!req->r_reply_info.head->is_dentry) {
1041		ihold(d_inode(old_dentry));
1042		d_instantiate(dentry, d_inode(old_dentry));
1043	}
1044	ceph_mdsc_put_request(req);
1045	return err;
1046}
1047
1048static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
1049				 struct ceph_mds_request *req)
1050{
1051	int result = req->r_err ? req->r_err :
1052			le32_to_cpu(req->r_reply_info.head->result);
1053
1054	if (result == -EJUKEBOX)
1055		goto out;
1056
1057	/* If op failed, mark everyone involved for errors */
1058	if (result) {
1059		int pathlen = 0;
1060		u64 base = 0;
1061		char *path = ceph_mdsc_build_path(req->r_dentry, &pathlen,
1062						  &base, 0);
1063
1064		/* mark error on parent + clear complete */
1065		mapping_set_error(req->r_parent->i_mapping, result);
1066		ceph_dir_clear_complete(req->r_parent);
1067
1068		/* drop the dentry -- we don't know its status */
1069		if (!d_unhashed(req->r_dentry))
1070			d_drop(req->r_dentry);
1071
1072		/* mark inode itself for an error (since metadata is bogus) */
1073		mapping_set_error(req->r_old_inode->i_mapping, result);
1074
1075		pr_warn("ceph: async unlink failure path=(%llx)%s result=%d!\n",
1076			base, IS_ERR(path) ? "<<bad>>" : path, result);
1077		ceph_mdsc_free_path(path, pathlen);
1078	}
1079out:
1080	iput(req->r_old_inode);
1081	ceph_mdsc_release_dir_caps(req);
1082}
1083
1084static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)
1085{
1086	struct ceph_inode_info *ci = ceph_inode(dir);
1087	struct ceph_dentry_info *di;
1088	int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;
1089
1090	spin_lock(&ci->i_ceph_lock);
1091	if ((__ceph_caps_issued(ci, NULL) & want) == want) {
1092		ceph_take_cap_refs(ci, want, false);
1093		got = want;
1094	}
1095	spin_unlock(&ci->i_ceph_lock);
1096
1097	/* If we didn't get anything, return 0 */
1098	if (!got)
1099		return 0;
1100
1101        spin_lock(&dentry->d_lock);
1102        di = ceph_dentry(dentry);
1103	/*
1104	 * - We are holding Fx, which implies Fs caps.
1105	 * - Only support async unlink for primary linkage
1106	 */
1107	if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen ||
1108	    !(di->flags & CEPH_DENTRY_PRIMARY_LINK))
1109		want = 0;
1110        spin_unlock(&dentry->d_lock);
1111
1112	/* Do we still want what we've got? */
1113	if (want == got)
1114		return got;
1115
1116	ceph_put_cap_refs(ci, got);
1117	return 0;
1118}
1119
1120/*
1121 * rmdir and unlink are differ only by the metadata op code
1122 */
1123static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1124{
1125	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1126	struct ceph_mds_client *mdsc = fsc->mdsc;
1127	struct inode *inode = d_inode(dentry);
1128	struct ceph_mds_request *req;
1129	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
1130	int err = -EROFS;
1131	int op;
1132
1133	if (ceph_snap(dir) == CEPH_SNAPDIR) {
1134		/* rmdir .snap/foo is RMSNAP */
1135		dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
 
1136		op = CEPH_MDS_OP_RMSNAP;
1137	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
1138		dout("unlink/rmdir dir %p dn %p inode %p\n",
1139		     dir, dentry, inode);
1140		op = d_is_dir(dentry) ?
1141			CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1142	} else
1143		goto out;
1144retry:
1145	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1146	if (IS_ERR(req)) {
1147		err = PTR_ERR(req);
1148		goto out;
1149	}
1150	req->r_dentry = dget(dentry);
1151	req->r_num_caps = 2;
1152	req->r_parent = dir;
1153	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1154	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1155	req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1156
1157	if (try_async && op == CEPH_MDS_OP_UNLINK &&
1158	    (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {
1159		dout("async unlink on %llu/%.*s caps=%s", ceph_ino(dir),
1160		     dentry->d_name.len, dentry->d_name.name,
1161		     ceph_cap_string(req->r_dir_caps));
1162		set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
1163		req->r_callback = ceph_async_unlink_cb;
1164		req->r_old_inode = d_inode(dentry);
1165		ihold(req->r_old_inode);
1166		err = ceph_mdsc_submit_request(mdsc, dir, req);
1167		if (!err) {
1168			/*
1169			 * We have enough caps, so we assume that the unlink
1170			 * will succeed. Fix up the target inode and dcache.
1171			 */
1172			drop_nlink(inode);
1173			d_delete(dentry);
1174		} else if (err == -EJUKEBOX) {
1175			try_async = false;
1176			ceph_mdsc_put_request(req);
1177			goto retry;
1178		}
1179	} else {
1180		set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1181		err = ceph_mdsc_do_request(mdsc, dir, req);
1182		if (!err && !req->r_reply_info.head->is_dentry)
1183			d_delete(dentry);
1184	}
1185
1186	ceph_mdsc_put_request(req);
1187out:
1188	return err;
1189}
1190
1191static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
1192		       struct inode *new_dir, struct dentry *new_dentry,
1193		       unsigned int flags)
1194{
1195	struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
1196	struct ceph_mds_client *mdsc = fsc->mdsc;
1197	struct ceph_mds_request *req;
1198	int op = CEPH_MDS_OP_RENAME;
1199	int err;
1200
1201	if (flags)
1202		return -EINVAL;
1203
1204	if (ceph_snap(old_dir) != ceph_snap(new_dir))
1205		return -EXDEV;
1206	if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1207		if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1208			op = CEPH_MDS_OP_RENAMESNAP;
1209		else
1210			return -EROFS;
1211	} else if (old_dir != new_dir) {
1212		err = ceph_quota_check_rename(mdsc, d_inode(old_dentry),
1213					      new_dir);
1214		if (err)
1215			return err;
1216	}
1217
1218	dout("rename dir %p dentry %p to dir %p dentry %p\n",
1219	     old_dir, old_dentry, new_dir, new_dentry);
1220	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1221	if (IS_ERR(req))
1222		return PTR_ERR(req);
1223	ihold(old_dir);
1224	req->r_dentry = dget(new_dentry);
1225	req->r_num_caps = 2;
1226	req->r_old_dentry = dget(old_dentry);
1227	req->r_old_dentry_dir = old_dir;
1228	req->r_parent = new_dir;
1229	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1230	req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
1231	req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1232	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1233	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1234	/* release LINK_RDCACHE on source inode (mds will lock it) */
1235	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1236	if (d_really_is_positive(new_dentry)) {
1237		req->r_inode_drop =
1238			ceph_drop_caps_for_unlink(d_inode(new_dentry));
1239	}
1240	err = ceph_mdsc_do_request(mdsc, old_dir, req);
1241	if (!err && !req->r_reply_info.head->is_dentry) {
1242		/*
1243		 * Normally d_move() is done by fill_trace (called by
1244		 * do_request, above).  If there is no trace, we need
1245		 * to do it here.
1246		 */
1247		d_move(old_dentry, new_dentry);
1248	}
1249	ceph_mdsc_put_request(req);
1250	return err;
1251}
1252
1253/*
1254 * Move dentry to tail of mdsc->dentry_leases list when lease is updated.
1255 * Leases at front of the list will expire first. (Assume all leases have
1256 * similar duration)
1257 *
1258 * Called under dentry->d_lock.
1259 */
1260void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)
1261{
1262	struct dentry *dn = di->dentry;
1263	struct ceph_mds_client *mdsc;
1264
1265	dout("dentry_lease_touch %p %p '%pd'\n", di, dn, dn);
1266
1267	di->flags |= CEPH_DENTRY_LEASE_LIST;
1268	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1269		di->flags |= CEPH_DENTRY_REFERENCED;
1270		return;
1271	}
1272
1273	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1274	spin_lock(&mdsc->dentry_list_lock);
1275	list_move_tail(&di->lease_list, &mdsc->dentry_leases);
1276	spin_unlock(&mdsc->dentry_list_lock);
1277}
1278
1279static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,
1280				     struct ceph_dentry_info *di)
1281{
1282	di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);
1283	di->lease_gen = 0;
1284	di->time = jiffies;
1285	list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases);
1286}
1287
1288/*
1289 * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases
1290 * list if it's not in the list, otherwise set 'referenced' flag.
1291 *
1292 * Called under dentry->d_lock.
1293 */
1294void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)
1295{
1296	struct dentry *dn = di->dentry;
1297	struct ceph_mds_client *mdsc;
1298
1299	dout("dentry_dir_lease_touch %p %p '%pd' (offset 0x%llx)\n",
1300	     di, dn, dn, di->offset);
1301
1302	if (!list_empty(&di->lease_list)) {
1303		if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1304			/* don't remove dentry from dentry lease list
1305			 * if its lease is valid */
1306			if (__dentry_lease_is_valid(di))
1307				return;
1308		} else {
1309			di->flags |= CEPH_DENTRY_REFERENCED;
1310			return;
1311		}
1312	}
1313
1314	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1315		di->flags |= CEPH_DENTRY_REFERENCED;
1316		di->flags &= ~CEPH_DENTRY_LEASE_LIST;
1317		return;
1318	}
1319
1320	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1321	spin_lock(&mdsc->dentry_list_lock);
1322	__dentry_dir_lease_touch(mdsc, di),
1323	spin_unlock(&mdsc->dentry_list_lock);
1324}
1325
1326static void __dentry_lease_unlist(struct ceph_dentry_info *di)
1327{
1328	struct ceph_mds_client *mdsc;
1329	if (di->flags & CEPH_DENTRY_SHRINK_LIST)
1330		return;
1331	if (list_empty(&di->lease_list))
1332		return;
1333
1334	mdsc = ceph_sb_to_client(di->dentry->d_sb)->mdsc;
1335	spin_lock(&mdsc->dentry_list_lock);
1336	list_del_init(&di->lease_list);
1337	spin_unlock(&mdsc->dentry_list_lock);
1338}
1339
1340enum {
1341	KEEP	= 0,
1342	DELETE	= 1,
1343	TOUCH	= 2,
1344	STOP	= 4,
1345};
1346
1347struct ceph_lease_walk_control {
1348	bool dir_lease;
1349	bool expire_dir_lease;
1350	unsigned long nr_to_scan;
1351	unsigned long dir_lease_ttl;
1352};
1353
1354static unsigned long
1355__dentry_leases_walk(struct ceph_mds_client *mdsc,
1356		     struct ceph_lease_walk_control *lwc,
1357		     int (*check)(struct dentry*, void*))
1358{
1359	struct ceph_dentry_info *di, *tmp;
1360	struct dentry *dentry, *last = NULL;
1361	struct list_head* list;
1362        LIST_HEAD(dispose);
1363	unsigned long freed = 0;
1364	int ret = 0;
1365
1366	list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;
1367	spin_lock(&mdsc->dentry_list_lock);
1368	list_for_each_entry_safe(di, tmp, list, lease_list) {
1369		if (!lwc->nr_to_scan)
1370			break;
1371		--lwc->nr_to_scan;
1372
1373		dentry = di->dentry;
1374		if (last == dentry)
1375			break;
1376
1377		if (!spin_trylock(&dentry->d_lock))
1378			continue;
1379
1380		if (__lockref_is_dead(&dentry->d_lockref)) {
1381			list_del_init(&di->lease_list);
1382			goto next;
1383		}
1384
1385		ret = check(dentry, lwc);
1386		if (ret & TOUCH) {
1387			/* move it into tail of dir lease list */
1388			__dentry_dir_lease_touch(mdsc, di);
1389			if (!last)
1390				last = dentry;
1391		}
1392		if (ret & DELETE) {
1393			/* stale lease */
1394			di->flags &= ~CEPH_DENTRY_REFERENCED;
1395			if (dentry->d_lockref.count > 0) {
1396				/* update_dentry_lease() will re-add
1397				 * it to lease list, or
1398				 * ceph_d_delete() will return 1 when
1399				 * last reference is dropped */
1400				list_del_init(&di->lease_list);
1401			} else {
1402				di->flags |= CEPH_DENTRY_SHRINK_LIST;
1403				list_move_tail(&di->lease_list, &dispose);
1404				dget_dlock(dentry);
1405			}
1406		}
1407next:
1408		spin_unlock(&dentry->d_lock);
1409		if (ret & STOP)
1410			break;
1411	}
1412	spin_unlock(&mdsc->dentry_list_lock);
1413
1414	while (!list_empty(&dispose)) {
1415		di = list_first_entry(&dispose, struct ceph_dentry_info,
1416				      lease_list);
1417		dentry = di->dentry;
1418		spin_lock(&dentry->d_lock);
1419
1420		list_del_init(&di->lease_list);
1421		di->flags &= ~CEPH_DENTRY_SHRINK_LIST;
1422		if (di->flags & CEPH_DENTRY_REFERENCED) {
1423			spin_lock(&mdsc->dentry_list_lock);
1424			if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1425				list_add_tail(&di->lease_list,
1426					      &mdsc->dentry_leases);
1427			} else {
1428				__dentry_dir_lease_touch(mdsc, di);
1429			}
1430			spin_unlock(&mdsc->dentry_list_lock);
1431		} else {
1432			freed++;
1433		}
1434
1435		spin_unlock(&dentry->d_lock);
1436		/* ceph_d_delete() does the trick */
1437		dput(dentry);
1438	}
1439	return freed;
1440}
1441
1442static int __dentry_lease_check(struct dentry *dentry, void *arg)
1443{
1444	struct ceph_dentry_info *di = ceph_dentry(dentry);
1445	int ret;
1446
1447	if (__dentry_lease_is_valid(di))
1448		return STOP;
1449	ret = __dir_lease_try_check(dentry);
1450	if (ret == -EBUSY)
1451		return KEEP;
1452	if (ret > 0)
1453		return TOUCH;
1454	return DELETE;
1455}
1456
1457static int __dir_lease_check(struct dentry *dentry, void *arg)
1458{
1459	struct ceph_lease_walk_control *lwc = arg;
1460	struct ceph_dentry_info *di = ceph_dentry(dentry);
1461
1462	int ret = __dir_lease_try_check(dentry);
1463	if (ret == -EBUSY)
1464		return KEEP;
1465	if (ret > 0) {
1466		if (time_before(jiffies, di->time + lwc->dir_lease_ttl))
1467			return STOP;
1468		/* Move dentry to tail of dir lease list if we don't want
1469		 * to delete it. So dentries in the list are checked in a
1470		 * round robin manner */
1471		if (!lwc->expire_dir_lease)
1472			return TOUCH;
1473		if (dentry->d_lockref.count > 0 ||
1474		    (di->flags & CEPH_DENTRY_REFERENCED))
1475			return TOUCH;
1476		/* invalidate dir lease */
1477		di->lease_shared_gen = 0;
1478	}
1479	return DELETE;
1480}
1481
1482int ceph_trim_dentries(struct ceph_mds_client *mdsc)
1483{
1484	struct ceph_lease_walk_control lwc;
1485	unsigned long count;
1486	unsigned long freed;
1487
1488	spin_lock(&mdsc->caps_list_lock);
1489        if (mdsc->caps_use_max > 0 &&
1490            mdsc->caps_use_count > mdsc->caps_use_max)
1491		count = mdsc->caps_use_count - mdsc->caps_use_max;
1492	else
1493		count = 0;
1494        spin_unlock(&mdsc->caps_list_lock);
1495
1496	lwc.dir_lease = false;
1497	lwc.nr_to_scan  = CEPH_CAPS_PER_RELEASE * 2;
1498	freed = __dentry_leases_walk(mdsc, &lwc, __dentry_lease_check);
1499	if (!lwc.nr_to_scan) /* more invalid leases */
1500		return -EAGAIN;
1501
1502	if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)
1503		lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;
1504
1505	lwc.dir_lease = true;
1506	lwc.expire_dir_lease = freed < count;
1507	lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;
1508	freed +=__dentry_leases_walk(mdsc, &lwc, __dir_lease_check);
1509	if (!lwc.nr_to_scan) /* more to check */
1510		return -EAGAIN;
1511
1512	return freed > 0 ? 1 : 0;
1513}
1514
1515/*
1516 * Ensure a dentry lease will no longer revalidate.
1517 */
1518void ceph_invalidate_dentry_lease(struct dentry *dentry)
1519{
1520	struct ceph_dentry_info *di = ceph_dentry(dentry);
1521	spin_lock(&dentry->d_lock);
1522	di->time = jiffies;
1523	di->lease_shared_gen = 0;
1524	di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;
1525	__dentry_lease_unlist(di);
1526	spin_unlock(&dentry->d_lock);
1527}
1528
1529/*
1530 * Check if dentry lease is valid.  If not, delete the lease.  Try to
1531 * renew if the least is more than half up.
1532 */
1533static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
1534{
1535	struct ceph_mds_session *session;
1536
1537	if (!di->lease_gen)
1538		return false;
1539
1540	session = di->lease_session;
1541	if (session) {
1542		u32 gen;
1543		unsigned long ttl;
1544
1545		spin_lock(&session->s_gen_ttl_lock);
1546		gen = session->s_cap_gen;
1547		ttl = session->s_cap_ttl;
1548		spin_unlock(&session->s_gen_ttl_lock);
1549
1550		if (di->lease_gen == gen &&
1551		    time_before(jiffies, ttl) &&
1552		    time_before(jiffies, di->time))
1553			return true;
1554	}
1555	di->lease_gen = 0;
1556	return false;
1557}
1558
1559static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
1560{
1561	struct ceph_dentry_info *di;
 
 
 
 
1562	struct ceph_mds_session *session = NULL;
 
1563	u32 seq = 0;
1564	int valid = 0;
1565
1566	spin_lock(&dentry->d_lock);
1567	di = ceph_dentry(dentry);
1568	if (di && __dentry_lease_is_valid(di)) {
1569		valid = 1;
 
 
 
 
1570
1571		if (di->lease_renew_after &&
1572		    time_after(jiffies, di->lease_renew_after)) {
1573			/*
1574			 * We should renew. If we're in RCU walk mode
1575			 * though, we can't do that so just return
1576			 * -ECHILD.
1577			 */
1578			if (flags & LOOKUP_RCU) {
1579				valid = -ECHILD;
1580			} else {
1581				session = ceph_get_mds_session(di->lease_session);
1582				seq = di->lease_seq;
1583				di->lease_renew_after = 0;
1584				di->lease_renew_from = jiffies;
1585			}
1586		}
1587	}
1588	spin_unlock(&dentry->d_lock);
1589
1590	if (session) {
1591		ceph_mdsc_lease_send_msg(session, dentry,
1592					 CEPH_MDS_LEASE_RENEW, seq);
1593		ceph_put_mds_session(session);
1594	}
1595	dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1596	return valid;
1597}
1598
1599/*
1600 * Called under dentry->d_lock.
1601 */
1602static int __dir_lease_try_check(const struct dentry *dentry)
1603{
1604	struct ceph_dentry_info *di = ceph_dentry(dentry);
1605	struct inode *dir;
1606	struct ceph_inode_info *ci;
1607	int valid = 0;
1608
1609	if (!di->lease_shared_gen)
1610		return 0;
1611	if (IS_ROOT(dentry))
1612		return 0;
1613
1614	dir = d_inode(dentry->d_parent);
1615	ci = ceph_inode(dir);
1616
1617	if (spin_trylock(&ci->i_ceph_lock)) {
1618		if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen &&
1619		    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0))
1620			valid = 1;
1621		spin_unlock(&ci->i_ceph_lock);
1622	} else {
1623		valid = -EBUSY;
1624	}
1625
1626	if (!valid)
1627		di->lease_shared_gen = 0;
1628	return valid;
1629}
1630
1631/*
1632 * Check if directory-wide content lease/cap is valid.
1633 */
1634static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,
1635			      struct ceph_mds_client *mdsc)
1636{
1637	struct ceph_inode_info *ci = ceph_inode(dir);
1638	int valid;
1639	int shared_gen;
1640
1641	spin_lock(&ci->i_ceph_lock);
1642	valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1643	if (valid) {
1644		__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
1645		shared_gen = atomic_read(&ci->i_shared_gen);
1646	}
1647	spin_unlock(&ci->i_ceph_lock);
1648	if (valid) {
1649		struct ceph_dentry_info *di;
1650		spin_lock(&dentry->d_lock);
1651		di = ceph_dentry(dentry);
1652		if (dir == d_inode(dentry->d_parent) &&
1653		    di && di->lease_shared_gen == shared_gen)
1654			__ceph_dentry_dir_lease_touch(di);
1655		else
1656			valid = 0;
1657		spin_unlock(&dentry->d_lock);
1658	}
1659	dout("dir_lease_is_valid dir %p v%u dentry %p = %d\n",
1660	     dir, (unsigned)atomic_read(&ci->i_shared_gen), dentry, valid);
1661	return valid;
1662}
1663
1664/*
1665 * Check if cached dentry can be trusted.
1666 */
1667static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1668{
1669	int valid = 0;
1670	struct dentry *parent;
1671	struct inode *dir, *inode;
1672	struct ceph_mds_client *mdsc;
1673
1674	if (flags & LOOKUP_RCU) {
1675		parent = READ_ONCE(dentry->d_parent);
1676		dir = d_inode_rcu(parent);
1677		if (!dir)
1678			return -ECHILD;
1679		inode = d_inode_rcu(dentry);
1680	} else {
1681		parent = dget_parent(dentry);
1682		dir = d_inode(parent);
1683		inode = d_inode(dentry);
1684	}
1685
1686	dout("d_revalidate %p '%pd' inode %p offset 0x%llx\n", dentry,
1687	     dentry, inode, ceph_dentry(dentry)->offset);
 
1688
1689	mdsc = ceph_sb_to_client(dir->i_sb)->mdsc;
1690
1691	/* always trust cached snapped dentries, snapdir dentry */
1692	if (ceph_snap(dir) != CEPH_NOSNAP) {
1693		dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1694		     dentry, inode);
1695		valid = 1;
1696	} else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
 
 
 
 
1697		valid = 1;
1698	} else {
1699		valid = dentry_lease_is_valid(dentry, flags);
1700		if (valid == -ECHILD)
1701			return valid;
1702		if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {
1703			if (inode)
1704				valid = ceph_is_any_caps(inode);
1705			else
1706				valid = 1;
1707		}
1708	}
1709
1710	if (!valid) {
1711		struct ceph_mds_request *req;
1712		int op, err;
1713		u32 mask;
1714
1715		if (flags & LOOKUP_RCU)
1716			return -ECHILD;
1717
1718		percpu_counter_inc(&mdsc->metric.d_lease_mis);
1719
1720		op = ceph_snap(dir) == CEPH_SNAPDIR ?
1721			CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1722		req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
1723		if (!IS_ERR(req)) {
1724			req->r_dentry = dget(dentry);
1725			req->r_num_caps = 2;
1726			req->r_parent = dir;
1727
1728			mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1729			if (ceph_security_xattr_wanted(dir))
1730				mask |= CEPH_CAP_XATTR_SHARED;
1731			req->r_args.getattr.mask = cpu_to_le32(mask);
1732
1733			err = ceph_mdsc_do_request(mdsc, NULL, req);
1734			switch (err) {
1735			case 0:
1736				if (d_really_is_positive(dentry) &&
1737				    d_inode(dentry) == req->r_target_inode)
1738					valid = 1;
1739				break;
1740			case -ENOENT:
1741				if (d_really_is_negative(dentry))
1742					valid = 1;
1743				fallthrough;
1744			default:
1745				break;
1746			}
1747			ceph_mdsc_put_request(req);
1748			dout("d_revalidate %p lookup result=%d\n",
1749			     dentry, err);
1750		}
1751	} else {
1752		percpu_counter_inc(&mdsc->metric.d_lease_hit);
1753	}
1754
1755	dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1756	if (!valid)
1757		ceph_dir_clear_complete(dir);
1758
1759	if (!(flags & LOOKUP_RCU))
1760		dput(parent);
1761	return valid;
1762}
1763
1764/*
1765 * Delete unused dentry that doesn't have valid lease
1766 *
1767 * Called under dentry->d_lock.
1768 */
1769static int ceph_d_delete(const struct dentry *dentry)
1770{
1771	struct ceph_dentry_info *di;
1772
1773	/* won't release caps */
1774	if (d_really_is_negative(dentry))
1775		return 0;
1776	if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1777		return 0;
1778	/* vaild lease? */
1779	di = ceph_dentry(dentry);
1780	if (di) {
1781		if (__dentry_lease_is_valid(di))
1782			return 0;
1783		if (__dir_lease_try_check(dentry))
1784			return 0;
1785	}
1786	return 1;
1787}
1788
1789/*
1790 * Release our ceph_dentry_info.
1791 */
1792static void ceph_d_release(struct dentry *dentry)
1793{
1794	struct ceph_dentry_info *di = ceph_dentry(dentry);
1795	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
1796
1797	dout("d_release %p\n", dentry);
1798
1799	atomic64_dec(&fsc->mdsc->metric.total_dentries);
1800
1801	spin_lock(&dentry->d_lock);
1802	__dentry_lease_unlist(di);
1803	dentry->d_fsdata = NULL;
1804	spin_unlock(&dentry->d_lock);
1805
1806	if (di->lease_session)
1807		ceph_put_mds_session(di->lease_session);
1808	kmem_cache_free(ceph_dentry_cachep, di);
1809}
1810
1811/*
1812 * When the VFS prunes a dentry from the cache, we need to clear the
1813 * complete flag on the parent directory.
1814 *
1815 * Called under dentry->d_lock.
1816 */
1817static void ceph_d_prune(struct dentry *dentry)
1818{
1819	struct ceph_inode_info *dir_ci;
1820	struct ceph_dentry_info *di;
 
 
 
 
1821
1822	dout("ceph_d_prune %pd %p\n", dentry, dentry);
1823
1824	/* do we have a valid parent? */
1825	if (IS_ROOT(dentry))
1826		return;
1827
1828	/* we hold d_lock, so d_parent is stable */
1829	dir_ci = ceph_inode(d_inode(dentry->d_parent));
1830	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
1831		return;
1832
1833	/* who calls d_delete() should also disable dcache readdir */
1834	if (d_really_is_negative(dentry))
1835		return;
1836
1837	/* d_fsdata does not get cleared until d_release */
1838	if (!d_unhashed(dentry)) {
1839		__ceph_dir_clear_complete(dir_ci);
1840		return;
1841	}
1842
1843	/* Disable dcache readdir just in case that someone called d_drop()
1844	 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
1845	 * properly (dcache readdir is still enabled) */
1846	di = ceph_dentry(dentry);
1847	if (di->offset > 0 &&
1848	    di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
1849		__ceph_dir_clear_ordered(dir_ci);
1850}
1851
1852/*
1853 * read() on a dir.  This weird interface hack only works if mounted
1854 * with '-o dirstat'.
1855 */
1856static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1857			     loff_t *ppos)
1858{
1859	struct ceph_dir_file_info *dfi = file->private_data;
1860	struct inode *inode = file_inode(file);
1861	struct ceph_inode_info *ci = ceph_inode(inode);
1862	int left;
1863	const int bufsize = 1024;
1864
1865	if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1866		return -EISDIR;
1867
1868	if (!dfi->dir_info) {
1869		dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
1870		if (!dfi->dir_info)
1871			return -ENOMEM;
1872		dfi->dir_info_len =
1873			snprintf(dfi->dir_info, bufsize,
1874				"entries:   %20lld\n"
1875				" files:    %20lld\n"
1876				" subdirs:  %20lld\n"
1877				"rentries:  %20lld\n"
1878				" rfiles:   %20lld\n"
1879				" rsubdirs: %20lld\n"
1880				"rbytes:    %20lld\n"
1881				"rctime:    %10lld.%09ld\n",
1882				ci->i_files + ci->i_subdirs,
1883				ci->i_files,
1884				ci->i_subdirs,
1885				ci->i_rfiles + ci->i_rsubdirs,
1886				ci->i_rfiles,
1887				ci->i_rsubdirs,
1888				ci->i_rbytes,
1889				ci->i_rctime.tv_sec,
1890				ci->i_rctime.tv_nsec);
1891	}
1892
1893	if (*ppos >= dfi->dir_info_len)
1894		return 0;
1895	size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
1896	left = copy_to_user(buf, dfi->dir_info + *ppos, size);
1897	if (left == size)
1898		return -EFAULT;
1899	*ppos += (size - left);
1900	return size - left;
1901}
1902
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1903
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1904
1905/*
1906 * Return name hash for a given dentry.  This is dependent on
1907 * the parent directory's hash function.
1908 */
1909unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1910{
1911	struct ceph_inode_info *dci = ceph_inode(dir);
1912	unsigned hash;
1913
1914	switch (dci->i_dir_layout.dl_dir_hash) {
1915	case 0:	/* for backward compat */
1916	case CEPH_STR_HASH_LINUX:
1917		return dn->d_name.hash;
1918
1919	default:
1920		spin_lock(&dn->d_lock);
1921		hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1922				     dn->d_name.name, dn->d_name.len);
1923		spin_unlock(&dn->d_lock);
1924		return hash;
1925	}
1926}
1927
1928const struct file_operations ceph_dir_fops = {
1929	.read = ceph_read_dir,
1930	.iterate = ceph_readdir,
1931	.llseek = ceph_dir_llseek,
1932	.open = ceph_open,
1933	.release = ceph_release,
1934	.unlocked_ioctl = ceph_ioctl,
1935	.compat_ioctl = compat_ptr_ioctl,
1936	.fsync = ceph_fsync,
1937	.lock = ceph_lock,
1938	.flock = ceph_flock,
1939};
1940
1941const struct file_operations ceph_snapdir_fops = {
1942	.iterate = ceph_readdir,
1943	.llseek = ceph_dir_llseek,
1944	.open = ceph_open,
1945	.release = ceph_release,
1946};
1947
1948const struct inode_operations ceph_dir_iops = {
1949	.lookup = ceph_lookup,
1950	.permission = ceph_permission,
1951	.getattr = ceph_getattr,
1952	.setattr = ceph_setattr,
 
 
1953	.listxattr = ceph_listxattr,
1954	.get_acl = ceph_get_acl,
1955	.set_acl = ceph_set_acl,
1956	.mknod = ceph_mknod,
1957	.symlink = ceph_symlink,
1958	.mkdir = ceph_mkdir,
1959	.link = ceph_link,
1960	.unlink = ceph_unlink,
1961	.rmdir = ceph_unlink,
1962	.rename = ceph_rename,
1963	.create = ceph_create,
1964	.atomic_open = ceph_atomic_open,
1965};
1966
1967const struct inode_operations ceph_snapdir_iops = {
1968	.lookup = ceph_lookup,
1969	.permission = ceph_permission,
1970	.getattr = ceph_getattr,
1971	.mkdir = ceph_mkdir,
1972	.rmdir = ceph_unlink,
1973	.rename = ceph_rename,
1974};
1975
1976const struct dentry_operations ceph_dentry_ops = {
1977	.d_revalidate = ceph_d_revalidate,
1978	.d_delete = ceph_d_delete,
1979	.d_release = ceph_d_release,
1980	.d_prune = ceph_d_prune,
1981	.d_init = ceph_d_init,
 
 
 
 
 
 
 
1982};