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v3.15
 
   1#include <linux/ceph/ceph_debug.h>
   2
   3#include <linux/spinlock.h>
   4#include <linux/fs_struct.h>
   5#include <linux/namei.h>
   6#include <linux/slab.h>
   7#include <linux/sched.h>
 
   8
   9#include "super.h"
  10#include "mds_client.h"
  11
  12/*
  13 * Directory operations: readdir, lookup, create, link, unlink,
  14 * rename, etc.
  15 */
  16
  17/*
  18 * Ceph MDS operations are specified in terms of a base ino and
  19 * relative path.  Thus, the client can specify an operation on a
  20 * specific inode (e.g., a getattr due to fstat(2)), or as a path
  21 * relative to, say, the root directory.
  22 *
  23 * Normally, we limit ourselves to strict inode ops (no path component)
  24 * or dentry operations (a single path component relative to an ino).  The
  25 * exception to this is open_root_dentry(), which will open the mount
  26 * point by name.
  27 */
  28
  29const struct inode_operations ceph_dir_iops;
  30const struct file_operations ceph_dir_fops;
  31const struct dentry_operations ceph_dentry_ops;
  32
 
 
 
  33/*
  34 * Initialize ceph dentry state.
  35 */
  36int ceph_init_dentry(struct dentry *dentry)
  37{
  38	struct ceph_dentry_info *di;
 
  39
  40	if (dentry->d_fsdata)
  41		return 0;
  42
  43	di = kmem_cache_alloc(ceph_dentry_cachep, GFP_NOFS | __GFP_ZERO);
  44	if (!di)
  45		return -ENOMEM;          /* oh well */
  46
  47	spin_lock(&dentry->d_lock);
  48	if (dentry->d_fsdata) {
  49		/* lost a race */
  50		kmem_cache_free(ceph_dentry_cachep, di);
  51		goto out_unlock;
  52	}
  53
  54	if (ceph_snap(dentry->d_parent->d_inode) == CEPH_NOSNAP)
  55		d_set_d_op(dentry, &ceph_dentry_ops);
  56	else if (ceph_snap(dentry->d_parent->d_inode) == CEPH_SNAPDIR)
  57		d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
  58	else
  59		d_set_d_op(dentry, &ceph_snap_dentry_ops);
  60
  61	di->dentry = dentry;
  62	di->lease_session = NULL;
  63	dentry->d_time = jiffies;
  64	/* avoid reordering d_fsdata setup so that the check above is safe */
  65	smp_mb();
  66	dentry->d_fsdata = di;
  67	ceph_dentry_lru_add(dentry);
  68out_unlock:
  69	spin_unlock(&dentry->d_lock);
  70	return 0;
  71}
  72
  73struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry)
  74{
  75	struct inode *inode = NULL;
  76
  77	if (!dentry)
  78		return NULL;
  79
  80	spin_lock(&dentry->d_lock);
  81	if (!IS_ROOT(dentry)) {
  82		inode = dentry->d_parent->d_inode;
  83		ihold(inode);
  84	}
  85	spin_unlock(&dentry->d_lock);
  86	return inode;
 
 
 
 
 
 
 
 
 
 
  87}
  88
 
 
 
 
  89
  90/*
  91 * for readdir, we encode the directory frag and offset within that
  92 * frag into f_pos.
  93 */
  94static unsigned fpos_frag(loff_t p)
  95{
  96	return p >> 32;
 
 
 
 
 
  97}
 
  98static unsigned fpos_off(loff_t p)
  99{
 100	return p & 0xffffffff;
 101}
 102
 103static int fpos_cmp(loff_t l, loff_t r)
 104{
 105	int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
 106	if (v)
 107		return v;
 108	return (int)(fpos_off(l) - fpos_off(r));
 109}
 110
 111/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 112 * When possible, we try to satisfy a readdir by peeking at the
 113 * dcache.  We make this work by carefully ordering dentries on
 114 * d_u.d_child when we initially get results back from the MDS, and
 115 * falling back to a "normal" sync readdir if any dentries in the dir
 116 * are dropped.
 117 *
 118 * Complete dir indicates that we have all dentries in the dir.  It is
 119 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
 120 * the MDS if/when the directory is modified).
 121 */
 122static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 123			    u32 shared_gen)
 124{
 125	struct ceph_file_info *fi = file->private_data;
 126	struct dentry *parent = file->f_dentry;
 127	struct inode *dir = parent->d_inode;
 128	struct list_head *p;
 129	struct dentry *dentry, *last;
 130	struct ceph_dentry_info *di;
 
 
 131	int err = 0;
 132
 133	/* claim ref on last dentry we returned */
 134	last = fi->dentry;
 135	fi->dentry = NULL;
 136
 137	dout("__dcache_readdir %p v%u at %llu (last %p)\n",
 138	     dir, shared_gen, ctx->pos, last);
 139
 140	spin_lock(&parent->d_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 141
 142	/* start at beginning? */
 143	if (ctx->pos == 2 || last == NULL ||
 144	    fpos_cmp(ctx->pos, ceph_dentry(last)->offset) < 0) {
 145		if (list_empty(&parent->d_subdirs))
 146			goto out_unlock;
 147		p = parent->d_subdirs.prev;
 148		dout(" initial p %p/%p\n", p->prev, p->next);
 149	} else {
 150		p = last->d_u.d_child.prev;
 151	}
 152
 153more:
 154	dentry = list_entry(p, struct dentry, d_u.d_child);
 155	di = ceph_dentry(dentry);
 156	while (1) {
 157		dout(" p %p/%p %s d_subdirs %p/%p\n", p->prev, p->next,
 158		     d_unhashed(dentry) ? "!hashed" : "hashed",
 159		     parent->d_subdirs.prev, parent->d_subdirs.next);
 160		if (p == &parent->d_subdirs) {
 161			fi->flags |= CEPH_F_ATEND;
 162			goto out_unlock;
 163		}
 164		spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
 165		if (di->lease_shared_gen == shared_gen &&
 166		    !d_unhashed(dentry) && dentry->d_inode &&
 167		    ceph_snap(dentry->d_inode) != CEPH_SNAPDIR &&
 168		    ceph_ino(dentry->d_inode) != CEPH_INO_CEPH &&
 169		    fpos_cmp(ctx->pos, di->offset) <= 0)
 170			break;
 171		dout(" skipping %p %.*s at %llu (%llu)%s%s\n", dentry,
 172		     dentry->d_name.len, dentry->d_name.name, di->offset,
 173		     ctx->pos, d_unhashed(dentry) ? " unhashed" : "",
 174		     !dentry->d_inode ? " null" : "");
 175		spin_unlock(&dentry->d_lock);
 176		p = p->prev;
 177		dentry = list_entry(p, struct dentry, d_u.d_child);
 178		di = ceph_dentry(dentry);
 179	}
 180
 181	dget_dlock(dentry);
 182	spin_unlock(&dentry->d_lock);
 183	spin_unlock(&parent->d_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 184
 185	/* make sure a dentry wasn't dropped while we didn't have parent lock */
 186	if (!ceph_dir_is_complete(dir)) {
 187		dout(" lost dir complete on %p; falling back to mds\n", dir);
 188		dput(dentry);
 189		err = -EAGAIN;
 190		goto out;
 191	}
 
 
 
 
 
 192
 193	dout(" %llu (%llu) dentry %p %.*s %p\n", di->offset, ctx->pos,
 194	     dentry, dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
 195	if (!dir_emit(ctx, dentry->d_name.name,
 196		      dentry->d_name.len,
 197		      ceph_translate_ino(dentry->d_sb, dentry->d_inode->i_ino),
 198		      dentry->d_inode->i_mode >> 12)) {
 199		if (last) {
 200			/* remember our position */
 201			fi->dentry = last;
 202			fi->next_offset = fpos_off(di->offset);
 203		}
 204		dput(dentry);
 205		return 0;
 206	}
 207
 208	ctx->pos = di->offset + 1;
 209
 210	if (last)
 211		dput(last);
 212	last = dentry;
 213
 214	spin_lock(&parent->d_lock);
 215	p = p->prev;	/* advance to next dentry */
 216	goto more;
 217
 218out_unlock:
 219	spin_unlock(&parent->d_lock);
 220out:
 221	if (last)
 
 
 
 
 
 
 
 222		dput(last);
 
 
 
 
 
 
 223	return err;
 224}
 225
 226/*
 227 * make note of the last dentry we read, so we can
 228 * continue at the same lexicographical point,
 229 * regardless of what dir changes take place on the
 230 * server.
 231 */
 232static int note_last_dentry(struct ceph_file_info *fi, const char *name,
 233			    int len)
 234{
 235	kfree(fi->last_name);
 236	fi->last_name = kmalloc(len+1, GFP_NOFS);
 237	if (!fi->last_name)
 238		return -ENOMEM;
 239	memcpy(fi->last_name, name, len);
 240	fi->last_name[len] = 0;
 241	dout("note_last_dentry '%s'\n", fi->last_name);
 242	return 0;
 243}
 244
 245static int ceph_readdir(struct file *file, struct dir_context *ctx)
 246{
 247	struct ceph_file_info *fi = file->private_data;
 248	struct inode *inode = file_inode(file);
 249	struct ceph_inode_info *ci = ceph_inode(inode);
 250	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 251	struct ceph_mds_client *mdsc = fsc->mdsc;
 252	unsigned frag = fpos_frag(ctx->pos);
 253	int off = fpos_off(ctx->pos);
 254	int err;
 255	u32 ftype;
 256	struct ceph_mds_reply_info_parsed *rinfo;
 257
 258	dout("readdir %p file %p frag %u off %u\n", inode, file, frag, off);
 259	if (fi->flags & CEPH_F_ATEND)
 260		return 0;
 261
 262	/* always start with . and .. */
 263	if (ctx->pos == 0) {
 264		/* note dir version at start of readdir so we can tell
 265		 * if any dentries get dropped */
 266		fi->dir_release_count = atomic_read(&ci->i_release_count);
 267
 268		dout("readdir off 0 -> '.'\n");
 269		if (!dir_emit(ctx, ".", 1, 
 270			    ceph_translate_ino(inode->i_sb, inode->i_ino),
 271			    inode->i_mode >> 12))
 272			return 0;
 273		ctx->pos = 1;
 274		off = 1;
 275	}
 276	if (ctx->pos == 1) {
 277		ino_t ino = parent_ino(file->f_dentry);
 
 
 
 
 
 
 278		dout("readdir off 1 -> '..'\n");
 279		if (!dir_emit(ctx, "..", 2,
 280			    ceph_translate_ino(inode->i_sb, ino),
 281			    inode->i_mode >> 12))
 282			return 0;
 283		ctx->pos = 2;
 284		off = 2;
 285	}
 286
 287	/* can we use the dcache? */
 288	spin_lock(&ci->i_ceph_lock);
 289	if ((ctx->pos == 2 || fi->dentry) &&
 
 
 
 
 290	    !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
 291	    ceph_snap(inode) != CEPH_SNAPDIR &&
 292	    __ceph_dir_is_complete(ci) &&
 293	    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
 294		u32 shared_gen = ci->i_shared_gen;
 
 295		spin_unlock(&ci->i_ceph_lock);
 296		err = __dcache_readdir(file, ctx, shared_gen);
 297		if (err != -EAGAIN)
 298			return err;
 299		frag = fpos_frag(ctx->pos);
 300		off = fpos_off(ctx->pos);
 301	} else {
 302		spin_unlock(&ci->i_ceph_lock);
 303	}
 304	if (fi->dentry) {
 305		err = note_last_dentry(fi, fi->dentry->d_name.name,
 306				       fi->dentry->d_name.len);
 307		if (err)
 308			return err;
 309		dput(fi->dentry);
 310		fi->dentry = NULL;
 311	}
 312
 313	/* proceed with a normal readdir */
 314
 315more:
 316	/* do we have the correct frag content buffered? */
 317	if (fi->frag != frag || fi->last_readdir == NULL) {
 318		struct ceph_mds_request *req;
 319		int op = ceph_snap(inode) == CEPH_SNAPDIR ?
 320			CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
 321
 322		/* discard old result, if any */
 323		if (fi->last_readdir) {
 324			ceph_mdsc_put_request(fi->last_readdir);
 325			fi->last_readdir = NULL;
 
 
 
 
 
 
 
 
 
 
 326		}
 327
 328		dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
 329		     ceph_vinop(inode), frag, fi->last_name);
 330		req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 331		if (IS_ERR(req))
 332			return PTR_ERR(req);
 333		err = ceph_alloc_readdir_reply_buffer(req, inode);
 334		if (err) {
 335			ceph_mdsc_put_request(req);
 336			return err;
 337		}
 338		req->r_inode = inode;
 339		ihold(inode);
 340		req->r_dentry = dget(file->f_dentry);
 341		/* hints to request -> mds selection code */
 342		req->r_direct_mode = USE_AUTH_MDS;
 343		req->r_direct_hash = ceph_frag_value(frag);
 344		req->r_direct_is_hash = true;
 345		req->r_path2 = kstrdup(fi->last_name, GFP_NOFS);
 346		req->r_readdir_offset = fi->next_offset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 347		req->r_args.readdir.frag = cpu_to_le32(frag);
 
 
 
 
 
 
 348		err = ceph_mdsc_do_request(mdsc, NULL, req);
 349		if (err < 0) {
 350			ceph_mdsc_put_request(req);
 351			return err;
 352		}
 353		dout("readdir got and parsed readdir result=%d"
 354		     " on frag %x, end=%d, complete=%d\n", err, frag,
 
 355		     (int)req->r_reply_info.dir_end,
 356		     (int)req->r_reply_info.dir_complete);
 
 357
 358		if (!req->r_did_prepopulate) {
 359			dout("readdir !did_prepopulate");
 360			/* preclude from marking dir complete */
 361			fi->dir_release_count--;
 362		}
 363
 364		/* note next offset and last dentry name */
 365		rinfo = &req->r_reply_info;
 366		if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
 367			frag = le32_to_cpu(rinfo->dir_dir->frag);
 368			if (ceph_frag_is_leftmost(frag))
 369				fi->next_offset = 2;
 370			else
 371				fi->next_offset = 0;
 372			off = fi->next_offset;
 
 
 373		}
 374		fi->frag = frag;
 375		fi->offset = fi->next_offset;
 376		fi->last_readdir = req;
 377
 378		if (req->r_reply_info.dir_end) {
 379			kfree(fi->last_name);
 380			fi->last_name = NULL;
 381			if (ceph_frag_is_rightmost(frag))
 382				fi->next_offset = 2;
 383			else
 384				fi->next_offset = 0;
 
 
 
 
 
 385		} else {
 386			err = note_last_dentry(fi,
 387				       rinfo->dir_dname[rinfo->dir_nr-1],
 388				       rinfo->dir_dname_len[rinfo->dir_nr-1]);
 389			if (err)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 390				return err;
 391			fi->next_offset += rinfo->dir_nr;
 
 
 
 392		}
 393	}
 394
 395	rinfo = &fi->last_readdir->r_reply_info;
 396	dout("readdir frag %x num %d off %d chunkoff %d\n", frag,
 397	     rinfo->dir_nr, off, fi->offset);
 398
 399	ctx->pos = ceph_make_fpos(frag, off);
 400	while (off >= fi->offset && off - fi->offset < rinfo->dir_nr) {
 401		struct ceph_mds_reply_inode *in =
 402			rinfo->dir_in[off - fi->offset].in;
 403		struct ceph_vino vino;
 404		ino_t ino;
 405
 406		dout("readdir off %d (%d/%d) -> %lld '%.*s' %p\n",
 407		     off, off - fi->offset, rinfo->dir_nr, ctx->pos,
 408		     rinfo->dir_dname_len[off - fi->offset],
 409		     rinfo->dir_dname[off - fi->offset], in);
 410		BUG_ON(!in);
 411		ftype = le32_to_cpu(in->mode) >> 12;
 412		vino.ino = le64_to_cpu(in->ino);
 413		vino.snap = le64_to_cpu(in->snapid);
 414		ino = ceph_vino_to_ino(vino);
 415		if (!dir_emit(ctx,
 416			    rinfo->dir_dname[off - fi->offset],
 417			    rinfo->dir_dname_len[off - fi->offset],
 418			    ceph_translate_ino(inode->i_sb, ino), ftype)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 419			dout("filldir stopping us...\n");
 420			return 0;
 421		}
 422		off++;
 423		ctx->pos++;
 424	}
 425
 426	if (fi->last_name) {
 427		ceph_mdsc_put_request(fi->last_readdir);
 428		fi->last_readdir = NULL;
 
 
 429		goto more;
 430	}
 431
 432	/* more frags? */
 433	if (!ceph_frag_is_rightmost(frag)) {
 434		frag = ceph_frag_next(frag);
 435		off = 0;
 436		ctx->pos = ceph_make_fpos(frag, off);
 
 
 
 
 
 
 
 
 
 
 437		dout("readdir next frag is %x\n", frag);
 438		goto more;
 439	}
 440	fi->flags |= CEPH_F_ATEND;
 441
 442	/*
 443	 * if dir_release_count still matches the dir, no dentries
 444	 * were released during the whole readdir, and we should have
 445	 * the complete dir contents in our cache.
 446	 */
 447	spin_lock(&ci->i_ceph_lock);
 448	if (atomic_read(&ci->i_release_count) == fi->dir_release_count) {
 449		dout(" marking %p complete\n", inode);
 450		__ceph_dir_set_complete(ci, fi->dir_release_count);
 
 
 
 
 
 
 
 
 
 
 
 
 
 451	}
 452	spin_unlock(&ci->i_ceph_lock);
 453
 454	dout("readdir %p file %p done.\n", inode, file);
 455	return 0;
 456}
 457
 458static void reset_readdir(struct ceph_file_info *fi, unsigned frag)
 459{
 460	if (fi->last_readdir) {
 461		ceph_mdsc_put_request(fi->last_readdir);
 462		fi->last_readdir = NULL;
 463	}
 464	kfree(fi->last_name);
 465	fi->last_name = NULL;
 466	if (ceph_frag_is_leftmost(frag))
 467		fi->next_offset = 2;  /* compensate for . and .. */
 468	else
 469		fi->next_offset = 0;
 470	if (fi->dentry) {
 471		dput(fi->dentry);
 472		fi->dentry = NULL;
 473	}
 474	fi->flags &= ~CEPH_F_ATEND;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 475}
 476
 477static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 478{
 479	struct ceph_file_info *fi = file->private_data;
 480	struct inode *inode = file->f_mapping->host;
 481	loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);
 482	loff_t retval;
 483
 484	mutex_lock(&inode->i_mutex);
 485	retval = -EINVAL;
 486	switch (whence) {
 487	case SEEK_END:
 488		offset += inode->i_size + 2;   /* FIXME */
 489		break;
 490	case SEEK_CUR:
 491		offset += file->f_pos;
 
 492	case SEEK_SET:
 493		break;
 
 
 
 494	default:
 495		goto out;
 496	}
 497
 498	if (offset >= 0) {
 
 
 
 
 
 
 
 
 
 
 499		if (offset != file->f_pos) {
 500			file->f_pos = offset;
 501			file->f_version = 0;
 502			fi->flags &= ~CEPH_F_ATEND;
 503		}
 504		retval = offset;
 505
 506		/*
 507		 * discard buffered readdir content on seekdir(0), or
 508		 * seek to new frag, or seek prior to current chunk.
 509		 */
 510		if (offset == 0 ||
 511		    fpos_frag(offset) != fi->frag ||
 512		    fpos_off(offset) < fi->offset) {
 513			dout("dir_llseek dropping %p content\n", file);
 514			reset_readdir(fi, fpos_frag(offset));
 515		}
 516
 517		/* bump dir_release_count if we did a forward seek */
 518		if (fpos_cmp(offset, old_offset) > 0)
 519			fi->dir_release_count--;
 520	}
 521out:
 522	mutex_unlock(&inode->i_mutex);
 523	return retval;
 524}
 525
 526/*
 527 * Handle lookups for the hidden .snap directory.
 528 */
 529int ceph_handle_snapdir(struct ceph_mds_request *req,
 530			struct dentry *dentry, int err)
 531{
 532	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 533	struct inode *parent = dentry->d_parent->d_inode; /* we hold i_mutex */
 534
 535	/* .snap dir? */
 536	if (err == -ENOENT &&
 537	    ceph_snap(parent) == CEPH_NOSNAP &&
 538	    strcmp(dentry->d_name.name,
 539		   fsc->mount_options->snapdir_name) == 0) {
 540		struct inode *inode = ceph_get_snapdir(parent);
 541		dout("ENOENT on snapdir %p '%.*s', linking to snapdir %p\n",
 542		     dentry, dentry->d_name.len, dentry->d_name.name, inode);
 543		BUG_ON(!d_unhashed(dentry));
 544		d_add(dentry, inode);
 545		err = 0;
 
 546	}
 547	return err;
 548}
 549
 550/*
 551 * Figure out final result of a lookup/open request.
 552 *
 553 * Mainly, make sure we return the final req->r_dentry (if it already
 554 * existed) in place of the original VFS-provided dentry when they
 555 * differ.
 556 *
 557 * Gracefully handle the case where the MDS replies with -ENOENT and
 558 * no trace (which it may do, at its discretion, e.g., if it doesn't
 559 * care to issue a lease on the negative dentry).
 560 */
 561struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 562				  struct dentry *dentry, int err)
 563{
 564	if (err == -ENOENT) {
 565		/* no trace? */
 566		err = 0;
 567		if (!req->r_reply_info.head->is_dentry) {
 568			dout("ENOENT and no trace, dentry %p inode %p\n",
 569			     dentry, dentry->d_inode);
 570			if (dentry->d_inode) {
 571				d_drop(dentry);
 572				err = -ENOENT;
 573			} else {
 574				d_add(dentry, NULL);
 575			}
 576		}
 577	}
 578	if (err)
 579		dentry = ERR_PTR(err);
 580	else if (dentry != req->r_dentry)
 581		dentry = dget(req->r_dentry);   /* we got spliced */
 582	else
 583		dentry = NULL;
 584	return dentry;
 585}
 586
 587static int is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
 588{
 589	return ceph_ino(inode) == CEPH_INO_ROOT &&
 590		strncmp(dentry->d_name.name, ".ceph", 5) == 0;
 591}
 592
 593/*
 594 * Look up a single dir entry.  If there is a lookup intent, inform
 595 * the MDS so that it gets our 'caps wanted' value in a single op.
 596 */
 597static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 598				  unsigned int flags)
 599{
 600	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 601	struct ceph_mds_client *mdsc = fsc->mdsc;
 602	struct ceph_mds_request *req;
 603	int op;
 
 604	int err;
 605
 606	dout("lookup %p dentry %p '%.*s'\n",
 607	     dir, dentry, dentry->d_name.len, dentry->d_name.name);
 608
 609	if (dentry->d_name.len > NAME_MAX)
 610		return ERR_PTR(-ENAMETOOLONG);
 611
 612	err = ceph_init_dentry(dentry);
 613	if (err < 0)
 614		return ERR_PTR(err);
 615
 616	/* can we conclude ENOENT locally? */
 617	if (dentry->d_inode == NULL) {
 618		struct ceph_inode_info *ci = ceph_inode(dir);
 619		struct ceph_dentry_info *di = ceph_dentry(dentry);
 620
 621		spin_lock(&ci->i_ceph_lock);
 622		dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
 623		if (strncmp(dentry->d_name.name,
 624			    fsc->mount_options->snapdir_name,
 625			    dentry->d_name.len) &&
 626		    !is_root_ceph_dentry(dir, dentry) &&
 
 627		    __ceph_dir_is_complete(ci) &&
 628		    (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
 
 629			spin_unlock(&ci->i_ceph_lock);
 630			dout(" dir %p complete, -ENOENT\n", dir);
 631			d_add(dentry, NULL);
 632			di->lease_shared_gen = ci->i_shared_gen;
 633			return NULL;
 634		}
 635		spin_unlock(&ci->i_ceph_lock);
 636	}
 637
 638	op = ceph_snap(dir) == CEPH_SNAPDIR ?
 639		CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
 640	req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
 641	if (IS_ERR(req))
 642		return ERR_CAST(req);
 643	req->r_dentry = dget(dentry);
 644	req->r_num_caps = 2;
 645	/* we only need inode linkage */
 646	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 647	req->r_locked_dir = dir;
 
 
 
 
 
 
 648	err = ceph_mdsc_do_request(mdsc, NULL, req);
 649	err = ceph_handle_snapdir(req, dentry, err);
 
 
 
 
 
 
 
 
 
 
 650	dentry = ceph_finish_lookup(req, dentry, err);
 651	ceph_mdsc_put_request(req);  /* will dput(dentry) */
 652	dout("lookup result=%p\n", dentry);
 653	return dentry;
 654}
 655
 656/*
 657 * If we do a create but get no trace back from the MDS, follow up with
 658 * a lookup (the VFS expects us to link up the provided dentry).
 659 */
 660int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
 661{
 662	struct dentry *result = ceph_lookup(dir, dentry, 0);
 663
 664	if (result && !IS_ERR(result)) {
 665		/*
 666		 * We created the item, then did a lookup, and found
 667		 * it was already linked to another inode we already
 668		 * had in our cache (and thus got spliced).  Link our
 669		 * dentry to that inode, but don't hash it, just in
 670		 * case the VFS wants to dereference it.
 
 
 
 
 
 671		 */
 672		BUG_ON(!result->d_inode);
 673		d_instantiate(dentry, result->d_inode);
 674		return 0;
 675	}
 676	return PTR_ERR(result);
 677}
 678
 679static int ceph_mknod(struct inode *dir, struct dentry *dentry,
 680		      umode_t mode, dev_t rdev)
 681{
 682	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 683	struct ceph_mds_client *mdsc = fsc->mdsc;
 684	struct ceph_mds_request *req;
 
 685	int err;
 686
 687	if (ceph_snap(dir) != CEPH_NOSNAP)
 688		return -EROFS;
 689
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 690	dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
 691	     dir, dentry, mode, rdev);
 692	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
 693	if (IS_ERR(req)) {
 694		d_drop(dentry);
 695		return PTR_ERR(req);
 696	}
 697	req->r_dentry = dget(dentry);
 698	req->r_num_caps = 2;
 699	req->r_locked_dir = dir;
 
 
 700	req->r_args.mknod.mode = cpu_to_le32(mode);
 701	req->r_args.mknod.rdev = cpu_to_le32(rdev);
 702	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 703	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 
 
 
 
 704	err = ceph_mdsc_do_request(mdsc, dir, req);
 705	if (!err && !req->r_reply_info.head->is_dentry)
 706		err = ceph_handle_notrace_create(dir, dentry);
 707	ceph_mdsc_put_request(req);
 708
 709	if (!err)
 710		ceph_init_acl(dentry, dentry->d_inode, dir);
 711	else
 712		d_drop(dentry);
 
 713	return err;
 714}
 715
 716static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 717		       bool excl)
 718{
 719	return ceph_mknod(dir, dentry, mode, 0);
 720}
 721
 722static int ceph_symlink(struct inode *dir, struct dentry *dentry,
 723			    const char *dest)
 724{
 725	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 726	struct ceph_mds_client *mdsc = fsc->mdsc;
 727	struct ceph_mds_request *req;
 
 728	int err;
 729
 730	if (ceph_snap(dir) != CEPH_NOSNAP)
 731		return -EROFS;
 732
 
 
 
 
 
 
 
 
 
 
 
 
 
 733	dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
 734	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
 735	if (IS_ERR(req)) {
 736		d_drop(dentry);
 737		return PTR_ERR(req);
 738	}
 
 
 
 
 
 
 
 
 
 
 739	req->r_dentry = dget(dentry);
 740	req->r_num_caps = 2;
 741	req->r_path2 = kstrdup(dest, GFP_NOFS);
 742	req->r_locked_dir = dir;
 743	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 744	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 
 
 
 
 745	err = ceph_mdsc_do_request(mdsc, dir, req);
 746	if (!err && !req->r_reply_info.head->is_dentry)
 747		err = ceph_handle_notrace_create(dir, dentry);
 748	ceph_mdsc_put_request(req);
 749	if (!err)
 750		ceph_init_acl(dentry, dentry->d_inode, dir);
 751	else
 752		d_drop(dentry);
 
 753	return err;
 754}
 755
 756static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 
 757{
 758	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 759	struct ceph_mds_client *mdsc = fsc->mdsc;
 760	struct ceph_mds_request *req;
 761	int err = -EROFS;
 
 762	int op;
 763
 
 
 
 
 764	if (ceph_snap(dir) == CEPH_SNAPDIR) {
 765		/* mkdir .snap/foo is a MKSNAP */
 766		op = CEPH_MDS_OP_MKSNAP;
 767		dout("mksnap dir %p snap '%.*s' dn %p\n", dir,
 768		     dentry->d_name.len, dentry->d_name.name, dentry);
 769	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
 770		dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
 771		op = CEPH_MDS_OP_MKDIR;
 772	} else {
 
 773		goto out;
 774	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 775	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 776	if (IS_ERR(req)) {
 777		err = PTR_ERR(req);
 778		goto out;
 779	}
 780
 781	req->r_dentry = dget(dentry);
 782	req->r_num_caps = 2;
 783	req->r_locked_dir = dir;
 
 
 784	req->r_args.mkdir.mode = cpu_to_le32(mode);
 785	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 786	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 
 
 
 
 787	err = ceph_mdsc_do_request(mdsc, dir, req);
 788	if (!err && !req->r_reply_info.head->is_dentry)
 
 
 789		err = ceph_handle_notrace_create(dir, dentry);
 790	ceph_mdsc_put_request(req);
 791out:
 792	if (!err)
 793		ceph_init_acl(dentry, dentry->d_inode, dir);
 794	else
 795		d_drop(dentry);
 
 796	return err;
 797}
 798
 799static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 800		     struct dentry *dentry)
 801{
 802	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 803	struct ceph_mds_client *mdsc = fsc->mdsc;
 804	struct ceph_mds_request *req;
 805	int err;
 806
 
 
 
 
 807	if (ceph_snap(dir) != CEPH_NOSNAP)
 808		return -EROFS;
 809
 810	dout("link in dir %p old_dentry %p dentry %p\n", dir,
 811	     old_dentry, dentry);
 812	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
 813	if (IS_ERR(req)) {
 814		d_drop(dentry);
 815		return PTR_ERR(req);
 816	}
 817	req->r_dentry = dget(dentry);
 818	req->r_num_caps = 2;
 819	req->r_old_dentry = dget(old_dentry);
 820	req->r_locked_dir = dir;
 
 
 821	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 822	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 823	/* release LINK_SHARED on source inode (mds will lock it) */
 824	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
 825	err = ceph_mdsc_do_request(mdsc, dir, req);
 826	if (err) {
 827		d_drop(dentry);
 828	} else if (!req->r_reply_info.head->is_dentry) {
 829		ihold(old_dentry->d_inode);
 830		d_instantiate(dentry, old_dentry->d_inode);
 831	}
 832	ceph_mdsc_put_request(req);
 833	return err;
 834}
 835
 836/*
 837 * For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps.  If it
 838 * looks like the link count will hit 0, drop any other caps (other
 839 * than PIN) we don't specifically want (due to the file still being
 840 * open).
 841 */
 842static int drop_caps_for_unlink(struct inode *inode)
 843{
 844	struct ceph_inode_info *ci = ceph_inode(inode);
 845	int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 846
 847	spin_lock(&ci->i_ceph_lock);
 848	if (inode->i_nlink == 1) {
 849		drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
 850		ci->i_ceph_flags |= CEPH_I_NODELAY;
 851	}
 852	spin_unlock(&ci->i_ceph_lock);
 853	return drop;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 854}
 855
 856/*
 857 * rmdir and unlink are differ only by the metadata op code
 858 */
 859static int ceph_unlink(struct inode *dir, struct dentry *dentry)
 860{
 861	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 862	struct ceph_mds_client *mdsc = fsc->mdsc;
 863	struct inode *inode = dentry->d_inode;
 864	struct ceph_mds_request *req;
 
 865	int err = -EROFS;
 866	int op;
 867
 868	if (ceph_snap(dir) == CEPH_SNAPDIR) {
 869		/* rmdir .snap/foo is RMSNAP */
 870		dout("rmsnap dir %p '%.*s' dn %p\n", dir, dentry->d_name.len,
 871		     dentry->d_name.name, dentry);
 872		op = CEPH_MDS_OP_RMSNAP;
 873	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
 874		dout("unlink/rmdir dir %p dn %p inode %p\n",
 875		     dir, dentry, inode);
 876		op = S_ISDIR(dentry->d_inode->i_mode) ?
 877			CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
 878	} else
 879		goto out;
 
 880	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 881	if (IS_ERR(req)) {
 882		err = PTR_ERR(req);
 883		goto out;
 884	}
 885	req->r_dentry = dget(dentry);
 886	req->r_num_caps = 2;
 887	req->r_locked_dir = dir;
 
 888	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 889	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 890	req->r_inode_drop = drop_caps_for_unlink(inode);
 891	err = ceph_mdsc_do_request(mdsc, dir, req);
 892	if (!err && !req->r_reply_info.head->is_dentry)
 893		d_delete(dentry);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 894	ceph_mdsc_put_request(req);
 895out:
 896	return err;
 897}
 898
 899static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 900		       struct inode *new_dir, struct dentry *new_dentry)
 
 901{
 902	struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
 903	struct ceph_mds_client *mdsc = fsc->mdsc;
 904	struct ceph_mds_request *req;
 
 905	int err;
 906
 
 
 
 907	if (ceph_snap(old_dir) != ceph_snap(new_dir))
 908		return -EXDEV;
 909	if (ceph_snap(old_dir) != CEPH_NOSNAP ||
 910	    ceph_snap(new_dir) != CEPH_NOSNAP)
 911		return -EROFS;
 
 
 
 
 
 
 
 
 
 
 
 
 912	dout("rename dir %p dentry %p to dir %p dentry %p\n",
 913	     old_dir, old_dentry, new_dir, new_dentry);
 914	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RENAME, USE_AUTH_MDS);
 915	if (IS_ERR(req))
 916		return PTR_ERR(req);
 917	ihold(old_dir);
 918	req->r_dentry = dget(new_dentry);
 919	req->r_num_caps = 2;
 920	req->r_old_dentry = dget(old_dentry);
 921	req->r_old_dentry_dir = old_dir;
 922	req->r_locked_dir = new_dir;
 
 
 923	req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
 924	req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
 925	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 926	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 927	/* release LINK_RDCACHE on source inode (mds will lock it) */
 928	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
 929	if (new_dentry->d_inode)
 930		req->r_inode_drop = drop_caps_for_unlink(new_dentry->d_inode);
 
 
 931	err = ceph_mdsc_do_request(mdsc, old_dir, req);
 932	if (!err && !req->r_reply_info.head->is_dentry) {
 933		/*
 934		 * Normally d_move() is done by fill_trace (called by
 935		 * do_request, above).  If there is no trace, we need
 936		 * to do it here.
 937		 */
 938
 939		d_move(old_dentry, new_dentry);
 940
 941		/* ensure target dentry is invalidated, despite
 942		   rehashing bug in vfs_rename_dir */
 943		ceph_invalidate_dentry_lease(new_dentry);
 944
 945		/* d_move screws up sibling dentries' offsets */
 946		ceph_dir_clear_complete(old_dir);
 947		ceph_dir_clear_complete(new_dir);
 948
 949	}
 950	ceph_mdsc_put_request(req);
 951	return err;
 952}
 953
 954/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 955 * Ensure a dentry lease will no longer revalidate.
 956 */
 957void ceph_invalidate_dentry_lease(struct dentry *dentry)
 958{
 
 959	spin_lock(&dentry->d_lock);
 960	dentry->d_time = jiffies;
 961	ceph_dentry(dentry)->lease_shared_gen = 0;
 
 
 962	spin_unlock(&dentry->d_lock);
 963}
 964
 965/*
 966 * Check if dentry lease is valid.  If not, delete the lease.  Try to
 967 * renew if the least is more than half up.
 968 */
 969static int dentry_lease_is_valid(struct dentry *dentry)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 970{
 971	struct ceph_dentry_info *di;
 972	struct ceph_mds_session *s;
 973	int valid = 0;
 974	u32 gen;
 975	unsigned long ttl;
 976	struct ceph_mds_session *session = NULL;
 977	struct inode *dir = NULL;
 978	u32 seq = 0;
 
 979
 980	spin_lock(&dentry->d_lock);
 981	di = ceph_dentry(dentry);
 982	if (di->lease_session) {
 983		s = di->lease_session;
 984		spin_lock(&s->s_gen_ttl_lock);
 985		gen = s->s_cap_gen;
 986		ttl = s->s_cap_ttl;
 987		spin_unlock(&s->s_gen_ttl_lock);
 988
 989		if (di->lease_gen == gen &&
 990		    time_before(jiffies, dentry->d_time) &&
 991		    time_before(jiffies, ttl)) {
 992			valid = 1;
 993			if (di->lease_renew_after &&
 994			    time_after(jiffies, di->lease_renew_after)) {
 995				/* we should renew */
 996				dir = dentry->d_parent->d_inode;
 997				session = ceph_get_mds_session(s);
 
 
 998				seq = di->lease_seq;
 999				di->lease_renew_after = 0;
1000				di->lease_renew_from = jiffies;
1001			}
1002		}
1003	}
1004	spin_unlock(&dentry->d_lock);
1005
1006	if (session) {
1007		ceph_mdsc_lease_send_msg(session, dir, dentry,
1008					 CEPH_MDS_LEASE_RENEW, seq);
1009		ceph_put_mds_session(session);
1010	}
1011	dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1012	return valid;
1013}
1014
1015/*
1016 * Check if directory-wide content lease/cap is valid.
1017 */
1018static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1019{
1020	struct ceph_inode_info *ci = ceph_inode(dir);
1021	struct ceph_dentry_info *di = ceph_dentry(dentry);
 
 
1022	int valid = 0;
1023
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1024	spin_lock(&ci->i_ceph_lock);
1025	if (ci->i_shared_gen == di->lease_shared_gen)
1026		valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
 
 
 
1027	spin_unlock(&ci->i_ceph_lock);
1028	dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1029	     dir, (unsigned)ci->i_shared_gen, dentry,
1030	     (unsigned)di->lease_shared_gen, valid);
 
 
 
 
 
 
 
 
 
 
1031	return valid;
1032}
1033
1034/*
1035 * Check if cached dentry can be trusted.
1036 */
1037static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1038{
1039	int valid = 0;
1040	struct inode *dir;
 
 
1041
1042	if (flags & LOOKUP_RCU)
1043		return -ECHILD;
 
 
 
 
 
 
 
 
 
1044
1045	dout("d_revalidate %p '%.*s' inode %p offset %lld\n", dentry,
1046	     dentry->d_name.len, dentry->d_name.name, dentry->d_inode,
1047	     ceph_dentry(dentry)->offset);
1048
1049	dir = ceph_get_dentry_parent_inode(dentry);
1050
1051	/* always trust cached snapped dentries, snapdir dentry */
1052	if (ceph_snap(dir) != CEPH_NOSNAP) {
1053		dout("d_revalidate %p '%.*s' inode %p is SNAPPED\n", dentry,
1054		     dentry->d_name.len, dentry->d_name.name, dentry->d_inode);
1055		valid = 1;
1056	} else if (dentry->d_inode &&
1057		   ceph_snap(dentry->d_inode) == CEPH_SNAPDIR) {
1058		valid = 1;
1059	} else if (dentry_lease_is_valid(dentry) ||
1060		   dir_lease_is_valid(dir, dentry)) {
1061		if (dentry->d_inode)
1062			valid = ceph_is_any_caps(dentry->d_inode);
1063		else
1064			valid = 1;
 
 
 
 
1065	}
1066
1067	dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1068	if (valid) {
1069		ceph_dentry_lru_touch(dentry);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1070	} else {
1071		ceph_dir_clear_complete(dir);
1072		d_drop(dentry);
1073	}
1074	iput(dir);
 
 
 
 
 
 
1075	return valid;
1076}
1077
1078/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1079 * Release our ceph_dentry_info.
1080 */
1081static void ceph_d_release(struct dentry *dentry)
1082{
1083	struct ceph_dentry_info *di = ceph_dentry(dentry);
 
1084
1085	dout("d_release %p\n", dentry);
1086	ceph_dentry_lru_del(dentry);
1087	if (di->lease_session)
1088		ceph_put_mds_session(di->lease_session);
1089	kmem_cache_free(ceph_dentry_cachep, di);
 
1090	dentry->d_fsdata = NULL;
1091}
1092
1093static int ceph_snapdir_d_revalidate(struct dentry *dentry,
1094					  unsigned int flags)
1095{
1096	/*
1097	 * Eventually, we'll want to revalidate snapped metadata
1098	 * too... probably...
1099	 */
1100	return 1;
1101}
1102
1103/*
1104 * When the VFS prunes a dentry from the cache, we need to clear the
1105 * complete flag on the parent directory.
1106 *
1107 * Called under dentry->d_lock.
1108 */
1109static void ceph_d_prune(struct dentry *dentry)
1110{
1111	dout("ceph_d_prune %p\n", dentry);
 
 
 
1112
1113	/* do we have a valid parent? */
1114	if (IS_ROOT(dentry))
1115		return;
1116
1117	/* if we are not hashed, we don't affect dir's completeness */
1118	if (d_unhashed(dentry))
 
1119		return;
1120
1121	/*
1122	 * we hold d_lock, so d_parent is stable, and d_fsdata is never
1123	 * cleared until d_release
1124	 */
1125	ceph_dir_clear_complete(dentry->d_parent->d_inode);
 
 
 
 
 
 
 
 
 
 
 
 
1126}
1127
1128/*
1129 * read() on a dir.  This weird interface hack only works if mounted
1130 * with '-o dirstat'.
1131 */
1132static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1133			     loff_t *ppos)
1134{
1135	struct ceph_file_info *cf = file->private_data;
1136	struct inode *inode = file_inode(file);
1137	struct ceph_inode_info *ci = ceph_inode(inode);
1138	int left;
1139	const int bufsize = 1024;
1140
1141	if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1142		return -EISDIR;
1143
1144	if (!cf->dir_info) {
1145		cf->dir_info = kmalloc(bufsize, GFP_NOFS);
1146		if (!cf->dir_info)
1147			return -ENOMEM;
1148		cf->dir_info_len =
1149			snprintf(cf->dir_info, bufsize,
1150				"entries:   %20lld\n"
1151				" files:    %20lld\n"
1152				" subdirs:  %20lld\n"
1153				"rentries:  %20lld\n"
1154				" rfiles:   %20lld\n"
1155				" rsubdirs: %20lld\n"
1156				"rbytes:    %20lld\n"
1157				"rctime:    %10ld.%09ld\n",
1158				ci->i_files + ci->i_subdirs,
1159				ci->i_files,
1160				ci->i_subdirs,
1161				ci->i_rfiles + ci->i_rsubdirs,
1162				ci->i_rfiles,
1163				ci->i_rsubdirs,
1164				ci->i_rbytes,
1165				(long)ci->i_rctime.tv_sec,
1166				(long)ci->i_rctime.tv_nsec);
1167	}
1168
1169	if (*ppos >= cf->dir_info_len)
1170		return 0;
1171	size = min_t(unsigned, size, cf->dir_info_len-*ppos);
1172	left = copy_to_user(buf, cf->dir_info + *ppos, size);
1173	if (left == size)
1174		return -EFAULT;
1175	*ppos += (size - left);
1176	return size - left;
1177}
1178
1179/*
1180 * an fsync() on a dir will wait for any uncommitted directory
1181 * operations to commit.
1182 */
1183static int ceph_dir_fsync(struct file *file, loff_t start, loff_t end,
1184			  int datasync)
1185{
1186	struct inode *inode = file_inode(file);
1187	struct ceph_inode_info *ci = ceph_inode(inode);
1188	struct list_head *head = &ci->i_unsafe_dirops;
1189	struct ceph_mds_request *req;
1190	u64 last_tid;
1191	int ret = 0;
1192
1193	dout("dir_fsync %p\n", inode);
1194	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1195	if (ret)
1196		return ret;
1197	mutex_lock(&inode->i_mutex);
1198
1199	spin_lock(&ci->i_unsafe_lock);
1200	if (list_empty(head))
1201		goto out;
1202
1203	req = list_entry(head->prev,
1204			 struct ceph_mds_request, r_unsafe_dir_item);
1205	last_tid = req->r_tid;
1206
1207	do {
1208		ceph_mdsc_get_request(req);
1209		spin_unlock(&ci->i_unsafe_lock);
1210
1211		dout("dir_fsync %p wait on tid %llu (until %llu)\n",
1212		     inode, req->r_tid, last_tid);
1213		if (req->r_timeout) {
1214			ret = wait_for_completion_timeout(
1215				&req->r_safe_completion, req->r_timeout);
1216			if (ret > 0)
1217				ret = 0;
1218			else if (ret == 0)
1219				ret = -EIO;  /* timed out */
1220		} else {
1221			wait_for_completion(&req->r_safe_completion);
1222		}
1223		ceph_mdsc_put_request(req);
1224
1225		spin_lock(&ci->i_unsafe_lock);
1226		if (ret || list_empty(head))
1227			break;
1228		req = list_entry(head->next,
1229				 struct ceph_mds_request, r_unsafe_dir_item);
1230	} while (req->r_tid < last_tid);
1231out:
1232	spin_unlock(&ci->i_unsafe_lock);
1233	mutex_unlock(&inode->i_mutex);
1234
1235	return ret;
1236}
1237
1238/*
1239 * We maintain a private dentry LRU.
1240 *
1241 * FIXME: this needs to be changed to a per-mds lru to be useful.
1242 */
1243void ceph_dentry_lru_add(struct dentry *dn)
1244{
1245	struct ceph_dentry_info *di = ceph_dentry(dn);
1246	struct ceph_mds_client *mdsc;
1247
1248	dout("dentry_lru_add %p %p '%.*s'\n", di, dn,
1249	     dn->d_name.len, dn->d_name.name);
1250	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1251	spin_lock(&mdsc->dentry_lru_lock);
1252	list_add_tail(&di->lru, &mdsc->dentry_lru);
1253	mdsc->num_dentry++;
1254	spin_unlock(&mdsc->dentry_lru_lock);
1255}
1256
1257void ceph_dentry_lru_touch(struct dentry *dn)
1258{
1259	struct ceph_dentry_info *di = ceph_dentry(dn);
1260	struct ceph_mds_client *mdsc;
1261
1262	dout("dentry_lru_touch %p %p '%.*s' (offset %lld)\n", di, dn,
1263	     dn->d_name.len, dn->d_name.name, di->offset);
1264	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1265	spin_lock(&mdsc->dentry_lru_lock);
1266	list_move_tail(&di->lru, &mdsc->dentry_lru);
1267	spin_unlock(&mdsc->dentry_lru_lock);
1268}
1269
1270void ceph_dentry_lru_del(struct dentry *dn)
1271{
1272	struct ceph_dentry_info *di = ceph_dentry(dn);
1273	struct ceph_mds_client *mdsc;
1274
1275	dout("dentry_lru_del %p %p '%.*s'\n", di, dn,
1276	     dn->d_name.len, dn->d_name.name);
1277	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1278	spin_lock(&mdsc->dentry_lru_lock);
1279	list_del_init(&di->lru);
1280	mdsc->num_dentry--;
1281	spin_unlock(&mdsc->dentry_lru_lock);
1282}
1283
1284/*
1285 * Return name hash for a given dentry.  This is dependent on
1286 * the parent directory's hash function.
1287 */
1288unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1289{
1290	struct ceph_inode_info *dci = ceph_inode(dir);
 
1291
1292	switch (dci->i_dir_layout.dl_dir_hash) {
1293	case 0:	/* for backward compat */
1294	case CEPH_STR_HASH_LINUX:
1295		return dn->d_name.hash;
1296
1297	default:
1298		return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
 
1299				     dn->d_name.name, dn->d_name.len);
 
 
1300	}
1301}
1302
1303const struct file_operations ceph_dir_fops = {
1304	.read = ceph_read_dir,
1305	.iterate = ceph_readdir,
1306	.llseek = ceph_dir_llseek,
1307	.open = ceph_open,
1308	.release = ceph_release,
1309	.unlocked_ioctl = ceph_ioctl,
1310	.fsync = ceph_dir_fsync,
 
 
 
 
 
 
 
 
 
 
1311};
1312
1313const struct inode_operations ceph_dir_iops = {
1314	.lookup = ceph_lookup,
1315	.permission = ceph_permission,
1316	.getattr = ceph_getattr,
1317	.setattr = ceph_setattr,
1318	.setxattr = ceph_setxattr,
1319	.getxattr = ceph_getxattr,
1320	.listxattr = ceph_listxattr,
1321	.removexattr = ceph_removexattr,
1322	.get_acl = ceph_get_acl,
1323	.set_acl = ceph_set_acl,
1324	.mknod = ceph_mknod,
1325	.symlink = ceph_symlink,
1326	.mkdir = ceph_mkdir,
1327	.link = ceph_link,
1328	.unlink = ceph_unlink,
1329	.rmdir = ceph_unlink,
1330	.rename = ceph_rename,
1331	.create = ceph_create,
1332	.atomic_open = ceph_atomic_open,
1333};
1334
1335const struct dentry_operations ceph_dentry_ops = {
1336	.d_revalidate = ceph_d_revalidate,
1337	.d_release = ceph_d_release,
1338	.d_prune = ceph_d_prune,
1339};
1340
1341const struct dentry_operations ceph_snapdir_dentry_ops = {
1342	.d_revalidate = ceph_snapdir_d_revalidate,
1343	.d_release = ceph_d_release,
1344};
1345
1346const struct dentry_operations ceph_snap_dentry_ops = {
 
 
1347	.d_release = ceph_d_release,
1348	.d_prune = ceph_d_prune,
 
1349};
v6.2
   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_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);
  42
  43	di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);
 
 
 
  44	if (!di)
  45		return -ENOMEM;          /* oh well */
  46
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  47	di->dentry = dentry;
  48	di->lease_session = NULL;
  49	di->time = jiffies;
 
 
  50	dentry->d_fsdata = di;
  51	INIT_LIST_HEAD(&di->lease_list);
 
 
 
 
  52
  53	atomic64_inc(&mdsc->metric.total_dentries);
 
 
  54
  55	return 0;
  56}
  57
  58/*
  59 * for f_pos for readdir:
  60 * - hash order:
  61 *	(0xff << 52) | ((24 bits hash) << 28) |
  62 *	(the nth entry has hash collision);
  63 * - frag+name order;
  64 *	((frag value) << 28) | (the nth entry in frag);
  65 */
  66#define OFFSET_BITS	28
  67#define OFFSET_MASK	((1 << OFFSET_BITS) - 1)
  68#define HASH_ORDER	(0xffull << (OFFSET_BITS + 24))
  69loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)
  70{
  71	loff_t fpos = ((loff_t)high << 28) | (loff_t)off;
  72	if (hash_order)
  73		fpos |= HASH_ORDER;
  74	return fpos;
  75}
  76
  77static bool is_hash_order(loff_t p)
  78{
  79	return (p & HASH_ORDER) == HASH_ORDER;
  80}
  81
 
 
 
 
  82static unsigned fpos_frag(loff_t p)
  83{
  84	return p >> OFFSET_BITS;
  85}
  86
  87static unsigned fpos_hash(loff_t p)
  88{
  89	return ceph_frag_value(fpos_frag(p));
  90}
  91
  92static unsigned fpos_off(loff_t p)
  93{
  94	return p & OFFSET_MASK;
  95}
  96
  97static int fpos_cmp(loff_t l, loff_t r)
  98{
  99	int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
 100	if (v)
 101		return v;
 102	return (int)(fpos_off(l) - fpos_off(r));
 103}
 104
 105/*
 106 * make note of the last dentry we read, so we can
 107 * continue at the same lexicographical point,
 108 * regardless of what dir changes take place on the
 109 * server.
 110 */
 111static int note_last_dentry(struct ceph_dir_file_info *dfi, const char *name,
 112		            int len, unsigned next_offset)
 113{
 114	char *buf = kmalloc(len+1, GFP_KERNEL);
 115	if (!buf)
 116		return -ENOMEM;
 117	kfree(dfi->last_name);
 118	dfi->last_name = buf;
 119	memcpy(dfi->last_name, name, len);
 120	dfi->last_name[len] = 0;
 121	dfi->next_offset = next_offset;
 122	dout("note_last_dentry '%s'\n", dfi->last_name);
 123	return 0;
 124}
 125
 126
 127static struct dentry *
 128__dcache_find_get_entry(struct dentry *parent, u64 idx,
 129			struct ceph_readdir_cache_control *cache_ctl)
 130{
 131	struct inode *dir = d_inode(parent);
 132	struct dentry *dentry;
 133	unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;
 134	loff_t ptr_pos = idx * sizeof(struct dentry *);
 135	pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;
 136
 137	if (ptr_pos >= i_size_read(dir))
 138		return NULL;
 139
 140	if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) {
 141		ceph_readdir_cache_release(cache_ctl);
 142		cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);
 143		if (!cache_ctl->page) {
 144			dout(" page %lu not found\n", ptr_pgoff);
 145			return ERR_PTR(-EAGAIN);
 146		}
 147		/* reading/filling the cache are serialized by
 148		   i_rwsem, no need to use page lock */
 149		unlock_page(cache_ctl->page);
 150		cache_ctl->dentries = kmap(cache_ctl->page);
 151	}
 152
 153	cache_ctl->index = idx & idx_mask;
 154
 155	rcu_read_lock();
 156	spin_lock(&parent->d_lock);
 157	/* check i_size again here, because empty directory can be
 158	 * marked as complete while not holding the i_rwsem. */
 159	if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))
 160		dentry = cache_ctl->dentries[cache_ctl->index];
 161	else
 162		dentry = NULL;
 163	spin_unlock(&parent->d_lock);
 164	if (dentry && !lockref_get_not_dead(&dentry->d_lockref))
 165		dentry = NULL;
 166	rcu_read_unlock();
 167	return dentry ? : ERR_PTR(-EAGAIN);
 168}
 169
 170/*
 171 * When possible, we try to satisfy a readdir by peeking at the
 172 * dcache.  We make this work by carefully ordering dentries on
 173 * d_child when we initially get results back from the MDS, and
 174 * falling back to a "normal" sync readdir if any dentries in the dir
 175 * are dropped.
 176 *
 177 * Complete dir indicates that we have all dentries in the dir.  It is
 178 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
 179 * the MDS if/when the directory is modified).
 180 */
 181static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 182			    int shared_gen)
 183{
 184	struct ceph_dir_file_info *dfi = file->private_data;
 185	struct dentry *parent = file->f_path.dentry;
 186	struct inode *dir = d_inode(parent);
 187	struct dentry *dentry, *last = NULL;
 
 188	struct ceph_dentry_info *di;
 189	struct ceph_readdir_cache_control cache_ctl = {};
 190	u64 idx = 0;
 191	int err = 0;
 192
 193	dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos);
 
 
 194
 195	/* search start position */
 196	if (ctx->pos > 2) {
 197		u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));
 198		while (count > 0) {
 199			u64 step = count >> 1;
 200			dentry = __dcache_find_get_entry(parent, idx + step,
 201							 &cache_ctl);
 202			if (!dentry) {
 203				/* use linar search */
 204				idx = 0;
 205				break;
 206			}
 207			if (IS_ERR(dentry)) {
 208				err = PTR_ERR(dentry);
 209				goto out;
 210			}
 211			di = ceph_dentry(dentry);
 212			spin_lock(&dentry->d_lock);
 213			if (fpos_cmp(di->offset, ctx->pos) < 0) {
 214				idx += step + 1;
 215				count -= step + 1;
 216			} else {
 217				count = step;
 218			}
 219			spin_unlock(&dentry->d_lock);
 220			dput(dentry);
 221		}
 222
 223		dout("__dcache_readdir %p cache idx %llu\n", dir, idx);
 
 
 
 
 
 
 
 
 224	}
 225
 226
 227	for (;;) {
 228		bool emit_dentry = false;
 229		dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);
 230		if (!dentry) {
 231			dfi->file_info.flags |= CEPH_F_ATEND;
 232			err = 0;
 
 
 
 
 
 
 
 
 
 
 233			break;
 234		}
 235		if (IS_ERR(dentry)) {
 236			err = PTR_ERR(dentry);
 237			goto out;
 238		}
 
 
 
 
 239
 240		spin_lock(&dentry->d_lock);
 241		di = ceph_dentry(dentry);
 242		if (d_unhashed(dentry) ||
 243		    d_really_is_negative(dentry) ||
 244		    di->lease_shared_gen != shared_gen) {
 245			spin_unlock(&dentry->d_lock);
 246			dput(dentry);
 247			err = -EAGAIN;
 248			goto out;
 249		}
 250		if (fpos_cmp(ctx->pos, di->offset) <= 0) {
 251			__ceph_dentry_dir_lease_touch(di);
 252			emit_dentry = true;
 253		}
 254		spin_unlock(&dentry->d_lock);
 255
 256		if (emit_dentry) {
 257			dout(" %llx dentry %p %pd %p\n", di->offset,
 258			     dentry, dentry, d_inode(dentry));
 259			ctx->pos = di->offset;
 260			if (!dir_emit(ctx, dentry->d_name.name,
 261				      dentry->d_name.len, ceph_present_inode(d_inode(dentry)),
 262				      d_inode(dentry)->i_mode >> 12)) {
 263				dput(dentry);
 264				err = 0;
 265				break;
 266			}
 267			ctx->pos++;
 268
 269			if (last)
 270				dput(last);
 271			last = dentry;
 272		} else {
 273			dput(dentry);
 
 
 
 
 
 274		}
 
 
 275	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 276out:
 277	ceph_readdir_cache_release(&cache_ctl);
 278	if (last) {
 279		int ret;
 280		di = ceph_dentry(last);
 281		ret = note_last_dentry(dfi, last->d_name.name, last->d_name.len,
 282				       fpos_off(di->offset) + 1);
 283		if (ret < 0)
 284			err = ret;
 285		dput(last);
 286		/* last_name no longer match cache index */
 287		if (dfi->readdir_cache_idx >= 0) {
 288			dfi->readdir_cache_idx = -1;
 289			dfi->dir_release_count = 0;
 290		}
 291	}
 292	return err;
 293}
 294
 295static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)
 
 
 
 
 
 
 
 296{
 297	if (!dfi->last_readdir)
 298		return true;
 299	if (is_hash_order(pos))
 300		return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));
 301	else
 302		return dfi->frag != fpos_frag(pos);
 
 
 303}
 304
 305static int ceph_readdir(struct file *file, struct dir_context *ctx)
 306{
 307	struct ceph_dir_file_info *dfi = file->private_data;
 308	struct inode *inode = file_inode(file);
 309	struct ceph_inode_info *ci = ceph_inode(inode);
 310	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 311	struct ceph_mds_client *mdsc = fsc->mdsc;
 312	int i;
 
 313	int err;
 314	unsigned frag = -1;
 315	struct ceph_mds_reply_info_parsed *rinfo;
 316
 317	dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos);
 318	if (dfi->file_info.flags & CEPH_F_ATEND)
 319		return 0;
 320
 321	/* always start with . and .. */
 322	if (ctx->pos == 0) {
 
 
 
 
 323		dout("readdir off 0 -> '.'\n");
 324		if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode),
 
 325			    inode->i_mode >> 12))
 326			return 0;
 327		ctx->pos = 1;
 
 328	}
 329	if (ctx->pos == 1) {
 330		u64 ino;
 331		struct dentry *dentry = file->f_path.dentry;
 332
 333		spin_lock(&dentry->d_lock);
 334		ino = ceph_present_inode(dentry->d_parent->d_inode);
 335		spin_unlock(&dentry->d_lock);
 336
 337		dout("readdir off 1 -> '..'\n");
 338		if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12))
 
 
 339			return 0;
 340		ctx->pos = 2;
 
 341	}
 342
 
 343	spin_lock(&ci->i_ceph_lock);
 344	/* request Fx cap. if have Fx, we don't need to release Fs cap
 345	 * for later create/unlink. */
 346	__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR);
 347	/* can we use the dcache? */
 348	if (ceph_test_mount_opt(fsc, DCACHE) &&
 349	    !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
 350	    ceph_snap(inode) != CEPH_SNAPDIR &&
 351	    __ceph_dir_is_complete_ordered(ci) &&
 352	    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
 353		int shared_gen = atomic_read(&ci->i_shared_gen);
 354
 355		spin_unlock(&ci->i_ceph_lock);
 356		err = __dcache_readdir(file, ctx, shared_gen);
 357		if (err != -EAGAIN)
 358			return err;
 
 
 359	} else {
 360		spin_unlock(&ci->i_ceph_lock);
 361	}
 
 
 
 
 
 
 
 
 362
 363	/* proceed with a normal readdir */
 
 364more:
 365	/* do we have the correct frag content buffered? */
 366	if (need_send_readdir(dfi, ctx->pos)) {
 367		struct ceph_mds_request *req;
 368		int op = ceph_snap(inode) == CEPH_SNAPDIR ?
 369			CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
 370
 371		/* discard old result, if any */
 372		if (dfi->last_readdir) {
 373			ceph_mdsc_put_request(dfi->last_readdir);
 374			dfi->last_readdir = NULL;
 375		}
 376
 377		if (is_hash_order(ctx->pos)) {
 378			/* fragtree isn't always accurate. choose frag
 379			 * based on previous reply when possible. */
 380			if (frag == (unsigned)-1)
 381				frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),
 382							NULL, NULL);
 383		} else {
 384			frag = fpos_frag(ctx->pos);
 385		}
 386
 387		dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
 388		     ceph_vinop(inode), frag, dfi->last_name);
 389		req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 390		if (IS_ERR(req))
 391			return PTR_ERR(req);
 392		err = ceph_alloc_readdir_reply_buffer(req, inode);
 393		if (err) {
 394			ceph_mdsc_put_request(req);
 395			return err;
 396		}
 
 
 
 397		/* hints to request -> mds selection code */
 398		req->r_direct_mode = USE_AUTH_MDS;
 399		if (op == CEPH_MDS_OP_READDIR) {
 400			req->r_direct_hash = ceph_frag_value(frag);
 401			__set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);
 402			req->r_inode_drop = CEPH_CAP_FILE_EXCL;
 403		}
 404		if (dfi->last_name) {
 405			req->r_path2 = kstrdup(dfi->last_name, GFP_KERNEL);
 406			if (!req->r_path2) {
 407				ceph_mdsc_put_request(req);
 408				return -ENOMEM;
 409			}
 410		} else if (is_hash_order(ctx->pos)) {
 411			req->r_args.readdir.offset_hash =
 412				cpu_to_le32(fpos_hash(ctx->pos));
 413		}
 414
 415		req->r_dir_release_cnt = dfi->dir_release_count;
 416		req->r_dir_ordered_cnt = dfi->dir_ordered_count;
 417		req->r_readdir_cache_idx = dfi->readdir_cache_idx;
 418		req->r_readdir_offset = dfi->next_offset;
 419		req->r_args.readdir.frag = cpu_to_le32(frag);
 420		req->r_args.readdir.flags =
 421				cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);
 422
 423		req->r_inode = inode;
 424		ihold(inode);
 425		req->r_dentry = dget(file->f_path.dentry);
 426		err = ceph_mdsc_do_request(mdsc, NULL, req);
 427		if (err < 0) {
 428			ceph_mdsc_put_request(req);
 429			return err;
 430		}
 431		dout("readdir got and parsed readdir result=%d on "
 432		     "frag %x, end=%d, complete=%d, hash_order=%d\n",
 433		     err, frag,
 434		     (int)req->r_reply_info.dir_end,
 435		     (int)req->r_reply_info.dir_complete,
 436		     (int)req->r_reply_info.hash_order);
 437
 
 
 
 
 
 
 
 438		rinfo = &req->r_reply_info;
 439		if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
 440			frag = le32_to_cpu(rinfo->dir_dir->frag);
 441			if (!rinfo->hash_order) {
 442				dfi->next_offset = req->r_readdir_offset;
 443				/* adjust ctx->pos to beginning of frag */
 444				ctx->pos = ceph_make_fpos(frag,
 445							  dfi->next_offset,
 446							  false);
 447			}
 448		}
 449
 450		dfi->frag = frag;
 451		dfi->last_readdir = req;
 452
 453		if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {
 454			dfi->readdir_cache_idx = req->r_readdir_cache_idx;
 455			if (dfi->readdir_cache_idx < 0) {
 456				/* preclude from marking dir ordered */
 457				dfi->dir_ordered_count = 0;
 458			} else if (ceph_frag_is_leftmost(frag) &&
 459				   dfi->next_offset == 2) {
 460				/* note dir version at start of readdir so
 461				 * we can tell if any dentries get dropped */
 462				dfi->dir_release_count = req->r_dir_release_cnt;
 463				dfi->dir_ordered_count = req->r_dir_ordered_cnt;
 464			}
 465		} else {
 466			dout("readdir !did_prepopulate\n");
 467			/* disable readdir cache */
 468			dfi->readdir_cache_idx = -1;
 469			/* preclude from marking dir complete */
 470			dfi->dir_release_count = 0;
 471		}
 472
 473		/* note next offset and last dentry name */
 474		if (rinfo->dir_nr > 0) {
 475			struct ceph_mds_reply_dir_entry *rde =
 476					rinfo->dir_entries + (rinfo->dir_nr-1);
 477			unsigned next_offset = req->r_reply_info.dir_end ?
 478					2 : (fpos_off(rde->offset) + 1);
 479			err = note_last_dentry(dfi, rde->name, rde->name_len,
 480					       next_offset);
 481			if (err) {
 482				ceph_mdsc_put_request(dfi->last_readdir);
 483				dfi->last_readdir = NULL;
 484				return err;
 485			}
 486		} else if (req->r_reply_info.dir_end) {
 487			dfi->next_offset = 2;
 488			/* keep last name */
 489		}
 490	}
 491
 492	rinfo = &dfi->last_readdir->r_reply_info;
 493	dout("readdir frag %x num %d pos %llx chunk first %llx\n",
 494	     dfi->frag, rinfo->dir_nr, ctx->pos,
 495	     rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);
 496
 497	i = 0;
 498	/* search start position */
 499	if (rinfo->dir_nr > 0) {
 500		int step, nr = rinfo->dir_nr;
 501		while (nr > 0) {
 502			step = nr >> 1;
 503			if (rinfo->dir_entries[i + step].offset < ctx->pos) {
 504				i +=  step + 1;
 505				nr -= step + 1;
 506			} else {
 507				nr = step;
 508			}
 509		}
 510	}
 511	for (; i < rinfo->dir_nr; i++) {
 512		struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
 513
 514		BUG_ON(rde->offset < ctx->pos);
 515
 516		ctx->pos = rde->offset;
 517		dout("readdir (%d/%d) -> %llx '%.*s' %p\n",
 518		     i, rinfo->dir_nr, ctx->pos,
 519		     rde->name_len, rde->name, &rde->inode.in);
 520
 521		BUG_ON(!rde->inode.in);
 522
 523		if (!dir_emit(ctx, rde->name, rde->name_len,
 524			      ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),
 525			      le32_to_cpu(rde->inode.in->mode) >> 12)) {
 526			/*
 527			 * NOTE: Here no need to put the 'dfi->last_readdir',
 528			 * because when dir_emit stops us it's most likely
 529			 * doesn't have enough memory, etc. So for next readdir
 530			 * it will continue.
 531			 */
 532			dout("filldir stopping us...\n");
 533			return 0;
 534		}
 
 535		ctx->pos++;
 536	}
 537
 538	ceph_mdsc_put_request(dfi->last_readdir);
 539	dfi->last_readdir = NULL;
 540
 541	if (dfi->next_offset > 2) {
 542		frag = dfi->frag;
 543		goto more;
 544	}
 545
 546	/* more frags? */
 547	if (!ceph_frag_is_rightmost(dfi->frag)) {
 548		frag = ceph_frag_next(dfi->frag);
 549		if (is_hash_order(ctx->pos)) {
 550			loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),
 551							dfi->next_offset, true);
 552			if (new_pos > ctx->pos)
 553				ctx->pos = new_pos;
 554			/* keep last_name */
 555		} else {
 556			ctx->pos = ceph_make_fpos(frag, dfi->next_offset,
 557							false);
 558			kfree(dfi->last_name);
 559			dfi->last_name = NULL;
 560		}
 561		dout("readdir next frag is %x\n", frag);
 562		goto more;
 563	}
 564	dfi->file_info.flags |= CEPH_F_ATEND;
 565
 566	/*
 567	 * if dir_release_count still matches the dir, no dentries
 568	 * were released during the whole readdir, and we should have
 569	 * the complete dir contents in our cache.
 570	 */
 571	if (atomic64_read(&ci->i_release_count) ==
 572					dfi->dir_release_count) {
 573		spin_lock(&ci->i_ceph_lock);
 574		if (dfi->dir_ordered_count ==
 575				atomic64_read(&ci->i_ordered_count)) {
 576			dout(" marking %p complete and ordered\n", inode);
 577			/* use i_size to track number of entries in
 578			 * readdir cache */
 579			BUG_ON(dfi->readdir_cache_idx < 0);
 580			i_size_write(inode, dfi->readdir_cache_idx *
 581				     sizeof(struct dentry*));
 582		} else {
 583			dout(" marking %p complete\n", inode);
 584		}
 585		__ceph_dir_set_complete(ci, dfi->dir_release_count,
 586					dfi->dir_ordered_count);
 587		spin_unlock(&ci->i_ceph_lock);
 588	}
 
 589
 590	dout("readdir %p file %p done.\n", inode, file);
 591	return 0;
 592}
 593
 594static void reset_readdir(struct ceph_dir_file_info *dfi)
 595{
 596	if (dfi->last_readdir) {
 597		ceph_mdsc_put_request(dfi->last_readdir);
 598		dfi->last_readdir = NULL;
 
 
 
 
 
 
 
 
 
 
 599	}
 600	kfree(dfi->last_name);
 601	dfi->last_name = NULL;
 602	dfi->dir_release_count = 0;
 603	dfi->readdir_cache_idx = -1;
 604	dfi->next_offset = 2;  /* compensate for . and .. */
 605	dfi->file_info.flags &= ~CEPH_F_ATEND;
 606}
 607
 608/*
 609 * discard buffered readdir content on seekdir(0), or seek to new frag,
 610 * or seek prior to current chunk
 611 */
 612static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)
 613{
 614	struct ceph_mds_reply_info_parsed *rinfo;
 615	loff_t chunk_offset;
 616	if (new_pos == 0)
 617		return true;
 618	if (is_hash_order(new_pos)) {
 619		/* no need to reset last_name for a forward seek when
 620		 * dentries are sotred in hash order */
 621	} else if (dfi->frag != fpos_frag(new_pos)) {
 622		return true;
 623	}
 624	rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;
 625	if (!rinfo || !rinfo->dir_nr)
 626		return true;
 627	chunk_offset = rinfo->dir_entries[0].offset;
 628	return new_pos < chunk_offset ||
 629	       is_hash_order(new_pos) != is_hash_order(chunk_offset);
 630}
 631
 632static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 633{
 634	struct ceph_dir_file_info *dfi = file->private_data;
 635	struct inode *inode = file->f_mapping->host;
 
 636	loff_t retval;
 637
 638	inode_lock(inode);
 639	retval = -EINVAL;
 640	switch (whence) {
 
 
 
 641	case SEEK_CUR:
 642		offset += file->f_pos;
 643		break;
 644	case SEEK_SET:
 645		break;
 646	case SEEK_END:
 647		retval = -EOPNOTSUPP;
 648		goto out;
 649	default:
 650		goto out;
 651	}
 652
 653	if (offset >= 0) {
 654		if (need_reset_readdir(dfi, offset)) {
 655			dout("dir_llseek dropping %p content\n", file);
 656			reset_readdir(dfi);
 657		} else if (is_hash_order(offset) && offset > file->f_pos) {
 658			/* for hash offset, we don't know if a forward seek
 659			 * is within same frag */
 660			dfi->dir_release_count = 0;
 661			dfi->readdir_cache_idx = -1;
 662		}
 663
 664		if (offset != file->f_pos) {
 665			file->f_pos = offset;
 666			file->f_version = 0;
 667			dfi->file_info.flags &= ~CEPH_F_ATEND;
 668		}
 669		retval = offset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 670	}
 671out:
 672	inode_unlock(inode);
 673	return retval;
 674}
 675
 676/*
 677 * Handle lookups for the hidden .snap directory.
 678 */
 679struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
 680				   struct dentry *dentry)
 681{
 682	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 683	struct inode *parent = d_inode(dentry->d_parent); /* we hold i_rwsem */
 684
 685	/* .snap dir? */
 686	if (ceph_snap(parent) == CEPH_NOSNAP &&
 687	    strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
 688		struct dentry *res;
 
 689		struct inode *inode = ceph_get_snapdir(parent);
 690
 691		res = d_splice_alias(inode, dentry);
 692		dout("ENOENT on snapdir %p '%pd', linking to snapdir %p. Spliced dentry %p\n",
 693		     dentry, dentry, inode, res);
 694		if (res)
 695			dentry = res;
 696	}
 697	return dentry;
 698}
 699
 700/*
 701 * Figure out final result of a lookup/open request.
 702 *
 703 * Mainly, make sure we return the final req->r_dentry (if it already
 704 * existed) in place of the original VFS-provided dentry when they
 705 * differ.
 706 *
 707 * Gracefully handle the case where the MDS replies with -ENOENT and
 708 * no trace (which it may do, at its discretion, e.g., if it doesn't
 709 * care to issue a lease on the negative dentry).
 710 */
 711struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 712				  struct dentry *dentry, int err)
 713{
 714	if (err == -ENOENT) {
 715		/* no trace? */
 716		err = 0;
 717		if (!req->r_reply_info.head->is_dentry) {
 718			dout("ENOENT and no trace, dentry %p inode %p\n",
 719			     dentry, d_inode(dentry));
 720			if (d_really_is_positive(dentry)) {
 721				d_drop(dentry);
 722				err = -ENOENT;
 723			} else {
 724				d_add(dentry, NULL);
 725			}
 726		}
 727	}
 728	if (err)
 729		dentry = ERR_PTR(err);
 730	else if (dentry != req->r_dentry)
 731		dentry = dget(req->r_dentry);   /* we got spliced */
 732	else
 733		dentry = NULL;
 734	return dentry;
 735}
 736
 737static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
 738{
 739	return ceph_ino(inode) == CEPH_INO_ROOT &&
 740		strncmp(dentry->d_name.name, ".ceph", 5) == 0;
 741}
 742
 743/*
 744 * Look up a single dir entry.  If there is a lookup intent, inform
 745 * the MDS so that it gets our 'caps wanted' value in a single op.
 746 */
 747static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 748				  unsigned int flags)
 749{
 750	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 751	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 752	struct ceph_mds_request *req;
 753	int op;
 754	int mask;
 755	int err;
 756
 757	dout("lookup %p dentry %p '%pd'\n",
 758	     dir, dentry, dentry);
 759
 760	if (dentry->d_name.len > NAME_MAX)
 761		return ERR_PTR(-ENAMETOOLONG);
 762
 
 
 
 
 763	/* can we conclude ENOENT locally? */
 764	if (d_really_is_negative(dentry)) {
 765		struct ceph_inode_info *ci = ceph_inode(dir);
 766		struct ceph_dentry_info *di = ceph_dentry(dentry);
 767
 768		spin_lock(&ci->i_ceph_lock);
 769		dout(" dir %p flags are 0x%lx\n", dir, ci->i_ceph_flags);
 770		if (strncmp(dentry->d_name.name,
 771			    fsc->mount_options->snapdir_name,
 772			    dentry->d_name.len) &&
 773		    !is_root_ceph_dentry(dir, dentry) &&
 774		    ceph_test_mount_opt(fsc, DCACHE) &&
 775		    __ceph_dir_is_complete(ci) &&
 776		    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
 777			__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
 778			spin_unlock(&ci->i_ceph_lock);
 779			dout(" dir %p complete, -ENOENT\n", dir);
 780			d_add(dentry, NULL);
 781			di->lease_shared_gen = atomic_read(&ci->i_shared_gen);
 782			return NULL;
 783		}
 784		spin_unlock(&ci->i_ceph_lock);
 785	}
 786
 787	op = ceph_snap(dir) == CEPH_SNAPDIR ?
 788		CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
 789	req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
 790	if (IS_ERR(req))
 791		return ERR_CAST(req);
 792	req->r_dentry = dget(dentry);
 793	req->r_num_caps = 2;
 794
 795	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
 796	if (ceph_security_xattr_wanted(dir))
 797		mask |= CEPH_CAP_XATTR_SHARED;
 798	req->r_args.getattr.mask = cpu_to_le32(mask);
 799
 800	ihold(dir);
 801	req->r_parent = dir;
 802	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 803	err = ceph_mdsc_do_request(mdsc, NULL, req);
 804	if (err == -ENOENT) {
 805		struct dentry *res;
 806
 807		res = ceph_handle_snapdir(req, dentry);
 808		if (IS_ERR(res)) {
 809			err = PTR_ERR(res);
 810		} else {
 811			dentry = res;
 812			err = 0;
 813		}
 814	}
 815	dentry = ceph_finish_lookup(req, dentry, err);
 816	ceph_mdsc_put_request(req);  /* will dput(dentry) */
 817	dout("lookup result=%p\n", dentry);
 818	return dentry;
 819}
 820
 821/*
 822 * If we do a create but get no trace back from the MDS, follow up with
 823 * a lookup (the VFS expects us to link up the provided dentry).
 824 */
 825int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
 826{
 827	struct dentry *result = ceph_lookup(dir, dentry, 0);
 828
 829	if (result && !IS_ERR(result)) {
 830		/*
 831		 * We created the item, then did a lookup, and found
 832		 * it was already linked to another inode we already
 833		 * had in our cache (and thus got spliced). To not
 834		 * confuse VFS (especially when inode is a directory),
 835		 * we don't link our dentry to that inode, return an
 836		 * error instead.
 837		 *
 838		 * This event should be rare and it happens only when
 839		 * we talk to old MDS. Recent MDS does not send traceless
 840		 * reply for request that creates new inode.
 841		 */
 842		d_drop(result);
 843		return -ESTALE;
 
 844	}
 845	return PTR_ERR(result);
 846}
 847
 848static int ceph_mknod(struct user_namespace *mnt_userns, struct inode *dir,
 849		      struct dentry *dentry, umode_t mode, dev_t rdev)
 850{
 851	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 
 852	struct ceph_mds_request *req;
 853	struct ceph_acl_sec_ctx as_ctx = {};
 854	int err;
 855
 856	if (ceph_snap(dir) != CEPH_NOSNAP)
 857		return -EROFS;
 858
 859	err = ceph_wait_on_conflict_unlink(dentry);
 860	if (err)
 861		return err;
 862
 863	if (ceph_quota_is_max_files_exceeded(dir)) {
 864		err = -EDQUOT;
 865		goto out;
 866	}
 867
 868	err = ceph_pre_init_acls(dir, &mode, &as_ctx);
 869	if (err < 0)
 870		goto out;
 871	err = ceph_security_init_secctx(dentry, mode, &as_ctx);
 872	if (err < 0)
 873		goto out;
 874
 875	dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
 876	     dir, dentry, mode, rdev);
 877	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
 878	if (IS_ERR(req)) {
 879		err = PTR_ERR(req);
 880		goto out;
 881	}
 882	req->r_dentry = dget(dentry);
 883	req->r_num_caps = 2;
 884	req->r_parent = dir;
 885	ihold(dir);
 886	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 887	req->r_args.mknod.mode = cpu_to_le32(mode);
 888	req->r_args.mknod.rdev = cpu_to_le32(rdev);
 889	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 890	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 891	if (as_ctx.pagelist) {
 892		req->r_pagelist = as_ctx.pagelist;
 893		as_ctx.pagelist = NULL;
 894	}
 895	err = ceph_mdsc_do_request(mdsc, dir, req);
 896	if (!err && !req->r_reply_info.head->is_dentry)
 897		err = ceph_handle_notrace_create(dir, dentry);
 898	ceph_mdsc_put_request(req);
 899out:
 900	if (!err)
 901		ceph_init_inode_acls(d_inode(dentry), &as_ctx);
 902	else
 903		d_drop(dentry);
 904	ceph_release_acl_sec_ctx(&as_ctx);
 905	return err;
 906}
 907
 908static int ceph_create(struct user_namespace *mnt_userns, struct inode *dir,
 909		       struct dentry *dentry, umode_t mode, bool excl)
 910{
 911	return ceph_mknod(mnt_userns, dir, dentry, mode, 0);
 912}
 913
 914static int ceph_symlink(struct user_namespace *mnt_userns, struct inode *dir,
 915			struct dentry *dentry, const char *dest)
 916{
 917	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 
 918	struct ceph_mds_request *req;
 919	struct ceph_acl_sec_ctx as_ctx = {};
 920	int err;
 921
 922	if (ceph_snap(dir) != CEPH_NOSNAP)
 923		return -EROFS;
 924
 925	err = ceph_wait_on_conflict_unlink(dentry);
 926	if (err)
 927		return err;
 928
 929	if (ceph_quota_is_max_files_exceeded(dir)) {
 930		err = -EDQUOT;
 931		goto out;
 932	}
 933
 934	err = ceph_security_init_secctx(dentry, S_IFLNK | 0777, &as_ctx);
 935	if (err < 0)
 936		goto out;
 937
 938	dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
 939	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
 940	if (IS_ERR(req)) {
 941		err = PTR_ERR(req);
 942		goto out;
 943	}
 944	req->r_path2 = kstrdup(dest, GFP_KERNEL);
 945	if (!req->r_path2) {
 946		err = -ENOMEM;
 947		ceph_mdsc_put_request(req);
 948		goto out;
 949	}
 950	req->r_parent = dir;
 951	ihold(dir);
 952
 953	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 954	req->r_dentry = dget(dentry);
 955	req->r_num_caps = 2;
 956	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
 
 
 957	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 958	if (as_ctx.pagelist) {
 959		req->r_pagelist = as_ctx.pagelist;
 960		as_ctx.pagelist = NULL;
 961	}
 962	err = ceph_mdsc_do_request(mdsc, dir, req);
 963	if (!err && !req->r_reply_info.head->is_dentry)
 964		err = ceph_handle_notrace_create(dir, dentry);
 965	ceph_mdsc_put_request(req);
 966out:
 967	if (err)
 
 968		d_drop(dentry);
 969	ceph_release_acl_sec_ctx(&as_ctx);
 970	return err;
 971}
 972
 973static int ceph_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 974		      struct dentry *dentry, umode_t mode)
 975{
 976	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 
 977	struct ceph_mds_request *req;
 978	struct ceph_acl_sec_ctx as_ctx = {};
 979	int err;
 980	int op;
 981
 982	err = ceph_wait_on_conflict_unlink(dentry);
 983	if (err)
 984		return err;
 985
 986	if (ceph_snap(dir) == CEPH_SNAPDIR) {
 987		/* mkdir .snap/foo is a MKSNAP */
 988		op = CEPH_MDS_OP_MKSNAP;
 989		dout("mksnap dir %p snap '%pd' dn %p\n", dir,
 990		     dentry, dentry);
 991	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
 992		dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
 993		op = CEPH_MDS_OP_MKDIR;
 994	} else {
 995		err = -EROFS;
 996		goto out;
 997	}
 998
 999	if (op == CEPH_MDS_OP_MKDIR &&
1000	    ceph_quota_is_max_files_exceeded(dir)) {
1001		err = -EDQUOT;
1002		goto out;
1003	}
1004
1005	mode |= S_IFDIR;
1006	err = ceph_pre_init_acls(dir, &mode, &as_ctx);
1007	if (err < 0)
1008		goto out;
1009	err = ceph_security_init_secctx(dentry, mode, &as_ctx);
1010	if (err < 0)
1011		goto out;
1012
1013	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1014	if (IS_ERR(req)) {
1015		err = PTR_ERR(req);
1016		goto out;
1017	}
1018
1019	req->r_dentry = dget(dentry);
1020	req->r_num_caps = 2;
1021	req->r_parent = dir;
1022	ihold(dir);
1023	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1024	req->r_args.mkdir.mode = cpu_to_le32(mode);
1025	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL;
1026	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1027	if (as_ctx.pagelist) {
1028		req->r_pagelist = as_ctx.pagelist;
1029		as_ctx.pagelist = NULL;
1030	}
1031	err = ceph_mdsc_do_request(mdsc, dir, req);
1032	if (!err &&
1033	    !req->r_reply_info.head->is_target &&
1034	    !req->r_reply_info.head->is_dentry)
1035		err = ceph_handle_notrace_create(dir, dentry);
1036	ceph_mdsc_put_request(req);
1037out:
1038	if (!err)
1039		ceph_init_inode_acls(d_inode(dentry), &as_ctx);
1040	else
1041		d_drop(dentry);
1042	ceph_release_acl_sec_ctx(&as_ctx);
1043	return err;
1044}
1045
1046static int ceph_link(struct dentry *old_dentry, struct inode *dir,
1047		     struct dentry *dentry)
1048{
1049	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 
1050	struct ceph_mds_request *req;
1051	int err;
1052
1053	err = ceph_wait_on_conflict_unlink(dentry);
1054	if (err)
1055		return err;
1056
1057	if (ceph_snap(dir) != CEPH_NOSNAP)
1058		return -EROFS;
1059
1060	dout("link in dir %p old_dentry %p dentry %p\n", dir,
1061	     old_dentry, dentry);
1062	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
1063	if (IS_ERR(req)) {
1064		d_drop(dentry);
1065		return PTR_ERR(req);
1066	}
1067	req->r_dentry = dget(dentry);
1068	req->r_num_caps = 2;
1069	req->r_old_dentry = dget(old_dentry);
1070	req->r_parent = dir;
1071	ihold(dir);
1072	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1073	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1074	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1075	/* release LINK_SHARED on source inode (mds will lock it) */
1076	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1077	err = ceph_mdsc_do_request(mdsc, dir, req);
1078	if (err) {
1079		d_drop(dentry);
1080	} else if (!req->r_reply_info.head->is_dentry) {
1081		ihold(d_inode(old_dentry));
1082		d_instantiate(dentry, d_inode(old_dentry));
1083	}
1084	ceph_mdsc_put_request(req);
1085	return err;
1086}
1087
1088static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,
1089				 struct ceph_mds_request *req)
 
 
 
 
 
1090{
1091	struct dentry *dentry = req->r_dentry;
1092	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
1093	struct ceph_dentry_info *di = ceph_dentry(dentry);
1094	int result = req->r_err ? req->r_err :
1095			le32_to_cpu(req->r_reply_info.head->result);
1096
1097	if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags))
1098		pr_warn("%s dentry %p:%pd async unlink bit is not set\n",
1099			__func__, dentry, dentry);
1100
1101	spin_lock(&fsc->async_unlink_conflict_lock);
1102	hash_del_rcu(&di->hnode);
1103	spin_unlock(&fsc->async_unlink_conflict_lock);
1104
1105	spin_lock(&dentry->d_lock);
1106	di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1107	wake_up_bit(&di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT);
1108	spin_unlock(&dentry->d_lock);
1109
1110	synchronize_rcu();
1111
1112	if (result == -EJUKEBOX)
1113		goto out;
1114
1115	/* If op failed, mark everyone involved for errors */
1116	if (result) {
1117		int pathlen = 0;
1118		u64 base = 0;
1119		char *path = ceph_mdsc_build_path(dentry, &pathlen,
1120						  &base, 0);
1121
1122		/* mark error on parent + clear complete */
1123		mapping_set_error(req->r_parent->i_mapping, result);
1124		ceph_dir_clear_complete(req->r_parent);
1125
1126		/* drop the dentry -- we don't know its status */
1127		if (!d_unhashed(dentry))
1128			d_drop(dentry);
1129
1130		/* mark inode itself for an error (since metadata is bogus) */
1131		mapping_set_error(req->r_old_inode->i_mapping, result);
1132
1133		pr_warn("async unlink failure path=(%llx)%s result=%d!\n",
1134			base, IS_ERR(path) ? "<<bad>>" : path, result);
1135		ceph_mdsc_free_path(path, pathlen);
1136	}
1137out:
1138	iput(req->r_old_inode);
1139	ceph_mdsc_release_dir_caps(req);
1140}
1141
1142static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)
1143{
1144	struct ceph_inode_info *ci = ceph_inode(dir);
1145	struct ceph_dentry_info *di;
1146	int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;
1147
1148	spin_lock(&ci->i_ceph_lock);
1149	if ((__ceph_caps_issued(ci, NULL) & want) == want) {
1150		ceph_take_cap_refs(ci, want, false);
1151		got = want;
1152	}
1153	spin_unlock(&ci->i_ceph_lock);
1154
1155	/* If we didn't get anything, return 0 */
1156	if (!got)
1157		return 0;
1158
1159        spin_lock(&dentry->d_lock);
1160        di = ceph_dentry(dentry);
1161	/*
1162	 * - We are holding Fx, which implies Fs caps.
1163	 * - Only support async unlink for primary linkage
1164	 */
1165	if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen ||
1166	    !(di->flags & CEPH_DENTRY_PRIMARY_LINK))
1167		want = 0;
1168        spin_unlock(&dentry->d_lock);
1169
1170	/* Do we still want what we've got? */
1171	if (want == got)
1172		return got;
1173
1174	ceph_put_cap_refs(ci, got);
1175	return 0;
1176}
1177
1178/*
1179 * rmdir and unlink are differ only by the metadata op code
1180 */
1181static int ceph_unlink(struct inode *dir, struct dentry *dentry)
1182{
1183	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
1184	struct ceph_mds_client *mdsc = fsc->mdsc;
1185	struct inode *inode = d_inode(dentry);
1186	struct ceph_mds_request *req;
1187	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);
1188	int err = -EROFS;
1189	int op;
1190
1191	if (ceph_snap(dir) == CEPH_SNAPDIR) {
1192		/* rmdir .snap/foo is RMSNAP */
1193		dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
 
1194		op = CEPH_MDS_OP_RMSNAP;
1195	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
1196		dout("unlink/rmdir dir %p dn %p inode %p\n",
1197		     dir, dentry, inode);
1198		op = d_is_dir(dentry) ?
1199			CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
1200	} else
1201		goto out;
1202retry:
1203	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1204	if (IS_ERR(req)) {
1205		err = PTR_ERR(req);
1206		goto out;
1207	}
1208	req->r_dentry = dget(dentry);
1209	req->r_num_caps = 2;
1210	req->r_parent = dir;
1211	ihold(dir);
1212	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1213	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1214	req->r_inode_drop = ceph_drop_caps_for_unlink(inode);
1215
1216	if (try_async && op == CEPH_MDS_OP_UNLINK &&
1217	    (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {
1218		struct ceph_dentry_info *di = ceph_dentry(dentry);
1219
1220		dout("async unlink on %llu/%.*s caps=%s", ceph_ino(dir),
1221		     dentry->d_name.len, dentry->d_name.name,
1222		     ceph_cap_string(req->r_dir_caps));
1223		set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);
1224		req->r_callback = ceph_async_unlink_cb;
1225		req->r_old_inode = d_inode(dentry);
1226		ihold(req->r_old_inode);
1227
1228		spin_lock(&dentry->d_lock);
1229		di->flags |= CEPH_DENTRY_ASYNC_UNLINK;
1230		spin_unlock(&dentry->d_lock);
1231
1232		spin_lock(&fsc->async_unlink_conflict_lock);
1233		hash_add_rcu(fsc->async_unlink_conflict, &di->hnode,
1234			     dentry->d_name.hash);
1235		spin_unlock(&fsc->async_unlink_conflict_lock);
1236
1237		err = ceph_mdsc_submit_request(mdsc, dir, req);
1238		if (!err) {
1239			/*
1240			 * We have enough caps, so we assume that the unlink
1241			 * will succeed. Fix up the target inode and dcache.
1242			 */
1243			drop_nlink(inode);
1244			d_delete(dentry);
1245		} else {
1246			spin_lock(&fsc->async_unlink_conflict_lock);
1247			hash_del_rcu(&di->hnode);
1248			spin_unlock(&fsc->async_unlink_conflict_lock);
1249
1250			spin_lock(&dentry->d_lock);
1251			di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;
1252			spin_unlock(&dentry->d_lock);
1253
1254			if (err == -EJUKEBOX) {
1255				try_async = false;
1256				ceph_mdsc_put_request(req);
1257				goto retry;
1258			}
1259		}
1260	} else {
1261		set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1262		err = ceph_mdsc_do_request(mdsc, dir, req);
1263		if (!err && !req->r_reply_info.head->is_dentry)
1264			d_delete(dentry);
1265	}
1266
1267	ceph_mdsc_put_request(req);
1268out:
1269	return err;
1270}
1271
1272static int ceph_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
1273		       struct dentry *old_dentry, struct inode *new_dir,
1274		       struct dentry *new_dentry, unsigned int flags)
1275{
1276	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb);
 
1277	struct ceph_mds_request *req;
1278	int op = CEPH_MDS_OP_RENAME;
1279	int err;
1280
1281	if (flags)
1282		return -EINVAL;
1283
1284	if (ceph_snap(old_dir) != ceph_snap(new_dir))
1285		return -EXDEV;
1286	if (ceph_snap(old_dir) != CEPH_NOSNAP) {
1287		if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
1288			op = CEPH_MDS_OP_RENAMESNAP;
1289		else
1290			return -EROFS;
1291	}
1292	/* don't allow cross-quota renames */
1293	if ((old_dir != new_dir) &&
1294	    (!ceph_quota_is_same_realm(old_dir, new_dir)))
1295		return -EXDEV;
1296
1297	err = ceph_wait_on_conflict_unlink(new_dentry);
1298	if (err)
1299		return err;
1300
1301	dout("rename dir %p dentry %p to dir %p dentry %p\n",
1302	     old_dir, old_dentry, new_dir, new_dentry);
1303	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1304	if (IS_ERR(req))
1305		return PTR_ERR(req);
1306	ihold(old_dir);
1307	req->r_dentry = dget(new_dentry);
1308	req->r_num_caps = 2;
1309	req->r_old_dentry = dget(old_dentry);
1310	req->r_old_dentry_dir = old_dir;
1311	req->r_parent = new_dir;
1312	ihold(new_dir);
1313	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
1314	req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
1315	req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
1316	req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
1317	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
1318	/* release LINK_RDCACHE on source inode (mds will lock it) */
1319	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
1320	if (d_really_is_positive(new_dentry)) {
1321		req->r_inode_drop =
1322			ceph_drop_caps_for_unlink(d_inode(new_dentry));
1323	}
1324	err = ceph_mdsc_do_request(mdsc, old_dir, req);
1325	if (!err && !req->r_reply_info.head->is_dentry) {
1326		/*
1327		 * Normally d_move() is done by fill_trace (called by
1328		 * do_request, above).  If there is no trace, we need
1329		 * to do it here.
1330		 */
 
1331		d_move(old_dentry, new_dentry);
 
 
 
 
 
 
 
 
 
1332	}
1333	ceph_mdsc_put_request(req);
1334	return err;
1335}
1336
1337/*
1338 * Move dentry to tail of mdsc->dentry_leases list when lease is updated.
1339 * Leases at front of the list will expire first. (Assume all leases have
1340 * similar duration)
1341 *
1342 * Called under dentry->d_lock.
1343 */
1344void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)
1345{
1346	struct dentry *dn = di->dentry;
1347	struct ceph_mds_client *mdsc;
1348
1349	dout("dentry_lease_touch %p %p '%pd'\n", di, dn, dn);
1350
1351	di->flags |= CEPH_DENTRY_LEASE_LIST;
1352	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1353		di->flags |= CEPH_DENTRY_REFERENCED;
1354		return;
1355	}
1356
1357	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1358	spin_lock(&mdsc->dentry_list_lock);
1359	list_move_tail(&di->lease_list, &mdsc->dentry_leases);
1360	spin_unlock(&mdsc->dentry_list_lock);
1361}
1362
1363static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,
1364				     struct ceph_dentry_info *di)
1365{
1366	di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);
1367	di->lease_gen = 0;
1368	di->time = jiffies;
1369	list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases);
1370}
1371
1372/*
1373 * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases
1374 * list if it's not in the list, otherwise set 'referenced' flag.
1375 *
1376 * Called under dentry->d_lock.
1377 */
1378void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)
1379{
1380	struct dentry *dn = di->dentry;
1381	struct ceph_mds_client *mdsc;
1382
1383	dout("dentry_dir_lease_touch %p %p '%pd' (offset 0x%llx)\n",
1384	     di, dn, dn, di->offset);
1385
1386	if (!list_empty(&di->lease_list)) {
1387		if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1388			/* don't remove dentry from dentry lease list
1389			 * if its lease is valid */
1390			if (__dentry_lease_is_valid(di))
1391				return;
1392		} else {
1393			di->flags |= CEPH_DENTRY_REFERENCED;
1394			return;
1395		}
1396	}
1397
1398	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {
1399		di->flags |= CEPH_DENTRY_REFERENCED;
1400		di->flags &= ~CEPH_DENTRY_LEASE_LIST;
1401		return;
1402	}
1403
1404	mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1405	spin_lock(&mdsc->dentry_list_lock);
1406	__dentry_dir_lease_touch(mdsc, di),
1407	spin_unlock(&mdsc->dentry_list_lock);
1408}
1409
1410static void __dentry_lease_unlist(struct ceph_dentry_info *di)
1411{
1412	struct ceph_mds_client *mdsc;
1413	if (di->flags & CEPH_DENTRY_SHRINK_LIST)
1414		return;
1415	if (list_empty(&di->lease_list))
1416		return;
1417
1418	mdsc = ceph_sb_to_client(di->dentry->d_sb)->mdsc;
1419	spin_lock(&mdsc->dentry_list_lock);
1420	list_del_init(&di->lease_list);
1421	spin_unlock(&mdsc->dentry_list_lock);
1422}
1423
1424enum {
1425	KEEP	= 0,
1426	DELETE	= 1,
1427	TOUCH	= 2,
1428	STOP	= 4,
1429};
1430
1431struct ceph_lease_walk_control {
1432	bool dir_lease;
1433	bool expire_dir_lease;
1434	unsigned long nr_to_scan;
1435	unsigned long dir_lease_ttl;
1436};
1437
1438static unsigned long
1439__dentry_leases_walk(struct ceph_mds_client *mdsc,
1440		     struct ceph_lease_walk_control *lwc,
1441		     int (*check)(struct dentry*, void*))
1442{
1443	struct ceph_dentry_info *di, *tmp;
1444	struct dentry *dentry, *last = NULL;
1445	struct list_head* list;
1446        LIST_HEAD(dispose);
1447	unsigned long freed = 0;
1448	int ret = 0;
1449
1450	list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;
1451	spin_lock(&mdsc->dentry_list_lock);
1452	list_for_each_entry_safe(di, tmp, list, lease_list) {
1453		if (!lwc->nr_to_scan)
1454			break;
1455		--lwc->nr_to_scan;
1456
1457		dentry = di->dentry;
1458		if (last == dentry)
1459			break;
1460
1461		if (!spin_trylock(&dentry->d_lock))
1462			continue;
1463
1464		if (__lockref_is_dead(&dentry->d_lockref)) {
1465			list_del_init(&di->lease_list);
1466			goto next;
1467		}
1468
1469		ret = check(dentry, lwc);
1470		if (ret & TOUCH) {
1471			/* move it into tail of dir lease list */
1472			__dentry_dir_lease_touch(mdsc, di);
1473			if (!last)
1474				last = dentry;
1475		}
1476		if (ret & DELETE) {
1477			/* stale lease */
1478			di->flags &= ~CEPH_DENTRY_REFERENCED;
1479			if (dentry->d_lockref.count > 0) {
1480				/* update_dentry_lease() will re-add
1481				 * it to lease list, or
1482				 * ceph_d_delete() will return 1 when
1483				 * last reference is dropped */
1484				list_del_init(&di->lease_list);
1485			} else {
1486				di->flags |= CEPH_DENTRY_SHRINK_LIST;
1487				list_move_tail(&di->lease_list, &dispose);
1488				dget_dlock(dentry);
1489			}
1490		}
1491next:
1492		spin_unlock(&dentry->d_lock);
1493		if (ret & STOP)
1494			break;
1495	}
1496	spin_unlock(&mdsc->dentry_list_lock);
1497
1498	while (!list_empty(&dispose)) {
1499		di = list_first_entry(&dispose, struct ceph_dentry_info,
1500				      lease_list);
1501		dentry = di->dentry;
1502		spin_lock(&dentry->d_lock);
1503
1504		list_del_init(&di->lease_list);
1505		di->flags &= ~CEPH_DENTRY_SHRINK_LIST;
1506		if (di->flags & CEPH_DENTRY_REFERENCED) {
1507			spin_lock(&mdsc->dentry_list_lock);
1508			if (di->flags & CEPH_DENTRY_LEASE_LIST) {
1509				list_add_tail(&di->lease_list,
1510					      &mdsc->dentry_leases);
1511			} else {
1512				__dentry_dir_lease_touch(mdsc, di);
1513			}
1514			spin_unlock(&mdsc->dentry_list_lock);
1515		} else {
1516			freed++;
1517		}
1518
1519		spin_unlock(&dentry->d_lock);
1520		/* ceph_d_delete() does the trick */
1521		dput(dentry);
1522	}
1523	return freed;
1524}
1525
1526static int __dentry_lease_check(struct dentry *dentry, void *arg)
1527{
1528	struct ceph_dentry_info *di = ceph_dentry(dentry);
1529	int ret;
1530
1531	if (__dentry_lease_is_valid(di))
1532		return STOP;
1533	ret = __dir_lease_try_check(dentry);
1534	if (ret == -EBUSY)
1535		return KEEP;
1536	if (ret > 0)
1537		return TOUCH;
1538	return DELETE;
1539}
1540
1541static int __dir_lease_check(struct dentry *dentry, void *arg)
1542{
1543	struct ceph_lease_walk_control *lwc = arg;
1544	struct ceph_dentry_info *di = ceph_dentry(dentry);
1545
1546	int ret = __dir_lease_try_check(dentry);
1547	if (ret == -EBUSY)
1548		return KEEP;
1549	if (ret > 0) {
1550		if (time_before(jiffies, di->time + lwc->dir_lease_ttl))
1551			return STOP;
1552		/* Move dentry to tail of dir lease list if we don't want
1553		 * to delete it. So dentries in the list are checked in a
1554		 * round robin manner */
1555		if (!lwc->expire_dir_lease)
1556			return TOUCH;
1557		if (dentry->d_lockref.count > 0 ||
1558		    (di->flags & CEPH_DENTRY_REFERENCED))
1559			return TOUCH;
1560		/* invalidate dir lease */
1561		di->lease_shared_gen = 0;
1562	}
1563	return DELETE;
1564}
1565
1566int ceph_trim_dentries(struct ceph_mds_client *mdsc)
1567{
1568	struct ceph_lease_walk_control lwc;
1569	unsigned long count;
1570	unsigned long freed;
1571
1572	spin_lock(&mdsc->caps_list_lock);
1573        if (mdsc->caps_use_max > 0 &&
1574            mdsc->caps_use_count > mdsc->caps_use_max)
1575		count = mdsc->caps_use_count - mdsc->caps_use_max;
1576	else
1577		count = 0;
1578        spin_unlock(&mdsc->caps_list_lock);
1579
1580	lwc.dir_lease = false;
1581	lwc.nr_to_scan  = CEPH_CAPS_PER_RELEASE * 2;
1582	freed = __dentry_leases_walk(mdsc, &lwc, __dentry_lease_check);
1583	if (!lwc.nr_to_scan) /* more invalid leases */
1584		return -EAGAIN;
1585
1586	if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)
1587		lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;
1588
1589	lwc.dir_lease = true;
1590	lwc.expire_dir_lease = freed < count;
1591	lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;
1592	freed +=__dentry_leases_walk(mdsc, &lwc, __dir_lease_check);
1593	if (!lwc.nr_to_scan) /* more to check */
1594		return -EAGAIN;
1595
1596	return freed > 0 ? 1 : 0;
1597}
1598
1599/*
1600 * Ensure a dentry lease will no longer revalidate.
1601 */
1602void ceph_invalidate_dentry_lease(struct dentry *dentry)
1603{
1604	struct ceph_dentry_info *di = ceph_dentry(dentry);
1605	spin_lock(&dentry->d_lock);
1606	di->time = jiffies;
1607	di->lease_shared_gen = 0;
1608	di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;
1609	__dentry_lease_unlist(di);
1610	spin_unlock(&dentry->d_lock);
1611}
1612
1613/*
1614 * Check if dentry lease is valid.  If not, delete the lease.  Try to
1615 * renew if the least is more than half up.
1616 */
1617static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)
1618{
1619	struct ceph_mds_session *session;
1620
1621	if (!di->lease_gen)
1622		return false;
1623
1624	session = di->lease_session;
1625	if (session) {
1626		u32 gen;
1627		unsigned long ttl;
1628
1629		gen = atomic_read(&session->s_cap_gen);
1630		ttl = session->s_cap_ttl;
1631
1632		if (di->lease_gen == gen &&
1633		    time_before(jiffies, ttl) &&
1634		    time_before(jiffies, di->time))
1635			return true;
1636	}
1637	di->lease_gen = 0;
1638	return false;
1639}
1640
1641static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)
1642{
1643	struct ceph_dentry_info *di;
 
 
 
 
1644	struct ceph_mds_session *session = NULL;
 
1645	u32 seq = 0;
1646	int valid = 0;
1647
1648	spin_lock(&dentry->d_lock);
1649	di = ceph_dentry(dentry);
1650	if (di && __dentry_lease_is_valid(di)) {
1651		valid = 1;
 
 
 
 
1652
1653		if (di->lease_renew_after &&
1654		    time_after(jiffies, di->lease_renew_after)) {
1655			/*
1656			 * We should renew. If we're in RCU walk mode
1657			 * though, we can't do that so just return
1658			 * -ECHILD.
1659			 */
1660			if (flags & LOOKUP_RCU) {
1661				valid = -ECHILD;
1662			} else {
1663				session = ceph_get_mds_session(di->lease_session);
1664				seq = di->lease_seq;
1665				di->lease_renew_after = 0;
1666				di->lease_renew_from = jiffies;
1667			}
1668		}
1669	}
1670	spin_unlock(&dentry->d_lock);
1671
1672	if (session) {
1673		ceph_mdsc_lease_send_msg(session, dentry,
1674					 CEPH_MDS_LEASE_RENEW, seq);
1675		ceph_put_mds_session(session);
1676	}
1677	dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1678	return valid;
1679}
1680
1681/*
1682 * Called under dentry->d_lock.
1683 */
1684static int __dir_lease_try_check(const struct dentry *dentry)
1685{
 
1686	struct ceph_dentry_info *di = ceph_dentry(dentry);
1687	struct inode *dir;
1688	struct ceph_inode_info *ci;
1689	int valid = 0;
1690
1691	if (!di->lease_shared_gen)
1692		return 0;
1693	if (IS_ROOT(dentry))
1694		return 0;
1695
1696	dir = d_inode(dentry->d_parent);
1697	ci = ceph_inode(dir);
1698
1699	if (spin_trylock(&ci->i_ceph_lock)) {
1700		if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen &&
1701		    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0))
1702			valid = 1;
1703		spin_unlock(&ci->i_ceph_lock);
1704	} else {
1705		valid = -EBUSY;
1706	}
1707
1708	if (!valid)
1709		di->lease_shared_gen = 0;
1710	return valid;
1711}
1712
1713/*
1714 * Check if directory-wide content lease/cap is valid.
1715 */
1716static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,
1717			      struct ceph_mds_client *mdsc)
1718{
1719	struct ceph_inode_info *ci = ceph_inode(dir);
1720	int valid;
1721	int shared_gen;
1722
1723	spin_lock(&ci->i_ceph_lock);
1724	valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1725	if (valid) {
1726		__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
1727		shared_gen = atomic_read(&ci->i_shared_gen);
1728	}
1729	spin_unlock(&ci->i_ceph_lock);
1730	if (valid) {
1731		struct ceph_dentry_info *di;
1732		spin_lock(&dentry->d_lock);
1733		di = ceph_dentry(dentry);
1734		if (dir == d_inode(dentry->d_parent) &&
1735		    di && di->lease_shared_gen == shared_gen)
1736			__ceph_dentry_dir_lease_touch(di);
1737		else
1738			valid = 0;
1739		spin_unlock(&dentry->d_lock);
1740	}
1741	dout("dir_lease_is_valid dir %p v%u dentry %p = %d\n",
1742	     dir, (unsigned)atomic_read(&ci->i_shared_gen), dentry, valid);
1743	return valid;
1744}
1745
1746/*
1747 * Check if cached dentry can be trusted.
1748 */
1749static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1750{
1751	int valid = 0;
1752	struct dentry *parent;
1753	struct inode *dir, *inode;
1754	struct ceph_mds_client *mdsc;
1755
1756	if (flags & LOOKUP_RCU) {
1757		parent = READ_ONCE(dentry->d_parent);
1758		dir = d_inode_rcu(parent);
1759		if (!dir)
1760			return -ECHILD;
1761		inode = d_inode_rcu(dentry);
1762	} else {
1763		parent = dget_parent(dentry);
1764		dir = d_inode(parent);
1765		inode = d_inode(dentry);
1766	}
1767
1768	dout("d_revalidate %p '%pd' inode %p offset 0x%llx\n", dentry,
1769	     dentry, inode, ceph_dentry(dentry)->offset);
 
1770
1771	mdsc = ceph_sb_to_client(dir->i_sb)->mdsc;
1772
1773	/* always trust cached snapped dentries, snapdir dentry */
1774	if (ceph_snap(dir) != CEPH_NOSNAP) {
1775		dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1776		     dentry, inode);
1777		valid = 1;
1778	} else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {
 
1779		valid = 1;
1780	} else {
1781		valid = dentry_lease_is_valid(dentry, flags);
1782		if (valid == -ECHILD)
1783			return valid;
1784		if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {
1785			if (inode)
1786				valid = ceph_is_any_caps(inode);
1787			else
1788				valid = 1;
1789		}
1790	}
1791
1792	if (!valid) {
1793		struct ceph_mds_request *req;
1794		int op, err;
1795		u32 mask;
1796
1797		if (flags & LOOKUP_RCU)
1798			return -ECHILD;
1799
1800		percpu_counter_inc(&mdsc->metric.d_lease_mis);
1801
1802		op = ceph_snap(dir) == CEPH_SNAPDIR ?
1803			CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
1804		req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
1805		if (!IS_ERR(req)) {
1806			req->r_dentry = dget(dentry);
1807			req->r_num_caps = 2;
1808			req->r_parent = dir;
1809			ihold(dir);
1810
1811			mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;
1812			if (ceph_security_xattr_wanted(dir))
1813				mask |= CEPH_CAP_XATTR_SHARED;
1814			req->r_args.getattr.mask = cpu_to_le32(mask);
1815
1816			err = ceph_mdsc_do_request(mdsc, NULL, req);
1817			switch (err) {
1818			case 0:
1819				if (d_really_is_positive(dentry) &&
1820				    d_inode(dentry) == req->r_target_inode)
1821					valid = 1;
1822				break;
1823			case -ENOENT:
1824				if (d_really_is_negative(dentry))
1825					valid = 1;
1826				fallthrough;
1827			default:
1828				break;
1829			}
1830			ceph_mdsc_put_request(req);
1831			dout("d_revalidate %p lookup result=%d\n",
1832			     dentry, err);
1833		}
1834	} else {
1835		percpu_counter_inc(&mdsc->metric.d_lease_hit);
 
1836	}
1837
1838	dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1839	if (!valid)
1840		ceph_dir_clear_complete(dir);
1841
1842	if (!(flags & LOOKUP_RCU))
1843		dput(parent);
1844	return valid;
1845}
1846
1847/*
1848 * Delete unused dentry that doesn't have valid lease
1849 *
1850 * Called under dentry->d_lock.
1851 */
1852static int ceph_d_delete(const struct dentry *dentry)
1853{
1854	struct ceph_dentry_info *di;
1855
1856	/* won't release caps */
1857	if (d_really_is_negative(dentry))
1858		return 0;
1859	if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
1860		return 0;
1861	/* vaild lease? */
1862	di = ceph_dentry(dentry);
1863	if (di) {
1864		if (__dentry_lease_is_valid(di))
1865			return 0;
1866		if (__dir_lease_try_check(dentry))
1867			return 0;
1868	}
1869	return 1;
1870}
1871
1872/*
1873 * Release our ceph_dentry_info.
1874 */
1875static void ceph_d_release(struct dentry *dentry)
1876{
1877	struct ceph_dentry_info *di = ceph_dentry(dentry);
1878	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
1879
1880	dout("d_release %p\n", dentry);
1881
1882	atomic64_dec(&fsc->mdsc->metric.total_dentries);
1883
1884	spin_lock(&dentry->d_lock);
1885	__dentry_lease_unlist(di);
1886	dentry->d_fsdata = NULL;
1887	spin_unlock(&dentry->d_lock);
1888
1889	ceph_put_mds_session(di->lease_session);
1890	kmem_cache_free(ceph_dentry_cachep, di);
 
 
 
 
 
 
1891}
1892
1893/*
1894 * When the VFS prunes a dentry from the cache, we need to clear the
1895 * complete flag on the parent directory.
1896 *
1897 * Called under dentry->d_lock.
1898 */
1899static void ceph_d_prune(struct dentry *dentry)
1900{
1901	struct ceph_inode_info *dir_ci;
1902	struct ceph_dentry_info *di;
1903
1904	dout("ceph_d_prune %pd %p\n", dentry, dentry);
1905
1906	/* do we have a valid parent? */
1907	if (IS_ROOT(dentry))
1908		return;
1909
1910	/* we hold d_lock, so d_parent is stable */
1911	dir_ci = ceph_inode(d_inode(dentry->d_parent));
1912	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
1913		return;
1914
1915	/* who calls d_delete() should also disable dcache readdir */
1916	if (d_really_is_negative(dentry))
1917		return;
1918
1919	/* d_fsdata does not get cleared until d_release */
1920	if (!d_unhashed(dentry)) {
1921		__ceph_dir_clear_complete(dir_ci);
1922		return;
1923	}
1924
1925	/* Disable dcache readdir just in case that someone called d_drop()
1926	 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED
1927	 * properly (dcache readdir is still enabled) */
1928	di = ceph_dentry(dentry);
1929	if (di->offset > 0 &&
1930	    di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))
1931		__ceph_dir_clear_ordered(dir_ci);
1932}
1933
1934/*
1935 * read() on a dir.  This weird interface hack only works if mounted
1936 * with '-o dirstat'.
1937 */
1938static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1939			     loff_t *ppos)
1940{
1941	struct ceph_dir_file_info *dfi = file->private_data;
1942	struct inode *inode = file_inode(file);
1943	struct ceph_inode_info *ci = ceph_inode(inode);
1944	int left;
1945	const int bufsize = 1024;
1946
1947	if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1948		return -EISDIR;
1949
1950	if (!dfi->dir_info) {
1951		dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);
1952		if (!dfi->dir_info)
1953			return -ENOMEM;
1954		dfi->dir_info_len =
1955			snprintf(dfi->dir_info, bufsize,
1956				"entries:   %20lld\n"
1957				" files:    %20lld\n"
1958				" subdirs:  %20lld\n"
1959				"rentries:  %20lld\n"
1960				" rfiles:   %20lld\n"
1961				" rsubdirs: %20lld\n"
1962				"rbytes:    %20lld\n"
1963				"rctime:    %10lld.%09ld\n",
1964				ci->i_files + ci->i_subdirs,
1965				ci->i_files,
1966				ci->i_subdirs,
1967				ci->i_rfiles + ci->i_rsubdirs,
1968				ci->i_rfiles,
1969				ci->i_rsubdirs,
1970				ci->i_rbytes,
1971				ci->i_rctime.tv_sec,
1972				ci->i_rctime.tv_nsec);
1973	}
1974
1975	if (*ppos >= dfi->dir_info_len)
1976		return 0;
1977	size = min_t(unsigned, size, dfi->dir_info_len-*ppos);
1978	left = copy_to_user(buf, dfi->dir_info + *ppos, size);
1979	if (left == size)
1980		return -EFAULT;
1981	*ppos += (size - left);
1982	return size - left;
1983}
1984
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1985
 
 
 
 
 
 
 
 
1986
1987/*
1988 * Return name hash for a given dentry.  This is dependent on
1989 * the parent directory's hash function.
1990 */
1991unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1992{
1993	struct ceph_inode_info *dci = ceph_inode(dir);
1994	unsigned hash;
1995
1996	switch (dci->i_dir_layout.dl_dir_hash) {
1997	case 0:	/* for backward compat */
1998	case CEPH_STR_HASH_LINUX:
1999		return dn->d_name.hash;
2000
2001	default:
2002		spin_lock(&dn->d_lock);
2003		hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
2004				     dn->d_name.name, dn->d_name.len);
2005		spin_unlock(&dn->d_lock);
2006		return hash;
2007	}
2008}
2009
2010const struct file_operations ceph_dir_fops = {
2011	.read = ceph_read_dir,
2012	.iterate = ceph_readdir,
2013	.llseek = ceph_dir_llseek,
2014	.open = ceph_open,
2015	.release = ceph_release,
2016	.unlocked_ioctl = ceph_ioctl,
2017	.compat_ioctl = compat_ptr_ioctl,
2018	.fsync = ceph_fsync,
2019	.lock = ceph_lock,
2020	.flock = ceph_flock,
2021};
2022
2023const struct file_operations ceph_snapdir_fops = {
2024	.iterate = ceph_readdir,
2025	.llseek = ceph_dir_llseek,
2026	.open = ceph_open,
2027	.release = ceph_release,
2028};
2029
2030const struct inode_operations ceph_dir_iops = {
2031	.lookup = ceph_lookup,
2032	.permission = ceph_permission,
2033	.getattr = ceph_getattr,
2034	.setattr = ceph_setattr,
 
 
2035	.listxattr = ceph_listxattr,
2036	.get_inode_acl = ceph_get_acl,
 
2037	.set_acl = ceph_set_acl,
2038	.mknod = ceph_mknod,
2039	.symlink = ceph_symlink,
2040	.mkdir = ceph_mkdir,
2041	.link = ceph_link,
2042	.unlink = ceph_unlink,
2043	.rmdir = ceph_unlink,
2044	.rename = ceph_rename,
2045	.create = ceph_create,
2046	.atomic_open = ceph_atomic_open,
2047};
2048
2049const struct inode_operations ceph_snapdir_iops = {
2050	.lookup = ceph_lookup,
2051	.permission = ceph_permission,
2052	.getattr = ceph_getattr,
2053	.mkdir = ceph_mkdir,
2054	.rmdir = ceph_unlink,
2055	.rename = ceph_rename,
 
 
2056};
2057
2058const struct dentry_operations ceph_dentry_ops = {
2059	.d_revalidate = ceph_d_revalidate,
2060	.d_delete = ceph_d_delete,
2061	.d_release = ceph_d_release,
2062	.d_prune = ceph_d_prune,
2063	.d_init = ceph_d_init,
2064};