brintos

brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.02#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#include "crypto.h"13 14/*15 * Directory operations: readdir, lookup, create, link, unlink,16 * rename, etc.17 */18 19/*20 * Ceph MDS operations are specified in terms of a base ino and21 * relative path.  Thus, the client can specify an operation on a22 * specific inode (e.g., a getattr due to fstat(2)), or as a path23 * relative to, say, the root directory.24 *25 * Normally, we limit ourselves to strict inode ops (no path component)26 * or dentry operations (a single path component relative to an ino).  The27 * exception to this is open_root_dentry(), which will open the mount28 * point by name.29 */30 31const struct dentry_operations ceph_dentry_ops;32 33static bool __dentry_lease_is_valid(struct ceph_dentry_info *di);34static int __dir_lease_try_check(const struct dentry *dentry);35 36/*37 * Initialize ceph dentry state.38 */39static int ceph_d_init(struct dentry *dentry)40{41	struct ceph_dentry_info *di;42	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);43 44	di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL);45	if (!di)46		return -ENOMEM;          /* oh well */47 48	di->dentry = dentry;49	di->lease_session = NULL;50	di->time = jiffies;51	dentry->d_fsdata = di;52	INIT_LIST_HEAD(&di->lease_list);53 54	atomic64_inc(&mdsc->metric.total_dentries);55 56	return 0;57}58 59/*60 * for f_pos for readdir:61 * - hash order:62 *	(0xff << 52) | ((24 bits hash) << 28) |63 *	(the nth entry has hash collision);64 * - frag+name order;65 *	((frag value) << 28) | (the nth entry in frag);66 */67#define OFFSET_BITS	2868#define OFFSET_MASK	((1 << OFFSET_BITS) - 1)69#define HASH_ORDER	(0xffull << (OFFSET_BITS + 24))70loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order)71{72	loff_t fpos = ((loff_t)high << 28) | (loff_t)off;73	if (hash_order)74		fpos |= HASH_ORDER;75	return fpos;76}77 78static bool is_hash_order(loff_t p)79{80	return (p & HASH_ORDER) == HASH_ORDER;81}82 83static unsigned fpos_frag(loff_t p)84{85	return p >> OFFSET_BITS;86}87 88static unsigned fpos_hash(loff_t p)89{90	return ceph_frag_value(fpos_frag(p));91}92 93static unsigned fpos_off(loff_t p)94{95	return p & OFFSET_MASK;96}97 98static int fpos_cmp(loff_t l, loff_t r)99{100	int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));101	if (v)102		return v;103	return (int)(fpos_off(l) - fpos_off(r));104}105 106/*107 * make note of the last dentry we read, so we can108 * continue at the same lexicographical point,109 * regardless of what dir changes take place on the110 * server.111 */112static int note_last_dentry(struct ceph_fs_client *fsc,113			    struct ceph_dir_file_info *dfi,114			    const char *name,115		            int len, unsigned next_offset)116{117	char *buf = kmalloc(len+1, GFP_KERNEL);118	if (!buf)119		return -ENOMEM;120	kfree(dfi->last_name);121	dfi->last_name = buf;122	memcpy(dfi->last_name, name, len);123	dfi->last_name[len] = 0;124	dfi->next_offset = next_offset;125	doutc(fsc->client, "'%s'\n", dfi->last_name);126	return 0;127}128 129 130static struct dentry *131__dcache_find_get_entry(struct dentry *parent, u64 idx,132			struct ceph_readdir_cache_control *cache_ctl)133{134	struct inode *dir = d_inode(parent);135	struct ceph_client *cl = ceph_inode_to_client(dir);136	struct dentry *dentry;137	unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1;138	loff_t ptr_pos = idx * sizeof(struct dentry *);139	pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT;140 141	if (ptr_pos >= i_size_read(dir))142		return NULL;143 144	if (!cache_ctl->page || ptr_pgoff != cache_ctl->page->index) {145		ceph_readdir_cache_release(cache_ctl);146		cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff);147		if (!cache_ctl->page) {148			doutc(cl, " page %lu not found\n", ptr_pgoff);149			return ERR_PTR(-EAGAIN);150		}151		/* reading/filling the cache are serialized by152		   i_rwsem, no need to use page lock */153		unlock_page(cache_ctl->page);154		cache_ctl->dentries = kmap(cache_ctl->page);155	}156 157	cache_ctl->index = idx & idx_mask;158 159	rcu_read_lock();160	spin_lock(&parent->d_lock);161	/* check i_size again here, because empty directory can be162	 * marked as complete while not holding the i_rwsem. */163	if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir))164		dentry = cache_ctl->dentries[cache_ctl->index];165	else166		dentry = NULL;167	spin_unlock(&parent->d_lock);168	if (dentry && !lockref_get_not_dead(&dentry->d_lockref))169		dentry = NULL;170	rcu_read_unlock();171	return dentry ? : ERR_PTR(-EAGAIN);172}173 174/*175 * When possible, we try to satisfy a readdir by peeking at the176 * dcache.  We make this work by carefully ordering dentries on177 * d_children when we initially get results back from the MDS, and178 * falling back to a "normal" sync readdir if any dentries in the dir179 * are dropped.180 *181 * Complete dir indicates that we have all dentries in the dir.  It is182 * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by183 * the MDS if/when the directory is modified).184 */185static int __dcache_readdir(struct file *file,  struct dir_context *ctx,186			    int shared_gen)187{188	struct ceph_dir_file_info *dfi = file->private_data;189	struct dentry *parent = file->f_path.dentry;190	struct inode *dir = d_inode(parent);191	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(dir);192	struct ceph_client *cl = ceph_inode_to_client(dir);193	struct dentry *dentry, *last = NULL;194	struct ceph_dentry_info *di;195	struct ceph_readdir_cache_control cache_ctl = {};196	u64 idx = 0;197	int err = 0;198 199	doutc(cl, "%p %llx.%llx v%u at %llx\n", dir, ceph_vinop(dir),200	      (unsigned)shared_gen, ctx->pos);201 202	/* search start position */203	if (ctx->pos > 2) {204		u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *));205		while (count > 0) {206			u64 step = count >> 1;207			dentry = __dcache_find_get_entry(parent, idx + step,208							 &cache_ctl);209			if (!dentry) {210				/* use linar search */211				idx = 0;212				break;213			}214			if (IS_ERR(dentry)) {215				err = PTR_ERR(dentry);216				goto out;217			}218			di = ceph_dentry(dentry);219			spin_lock(&dentry->d_lock);220			if (fpos_cmp(di->offset, ctx->pos) < 0) {221				idx += step + 1;222				count -= step + 1;223			} else {224				count = step;225			}226			spin_unlock(&dentry->d_lock);227			dput(dentry);228		}229 230		doutc(cl, "%p %llx.%llx cache idx %llu\n", dir,231		      ceph_vinop(dir), idx);232	}233 234 235	for (;;) {236		bool emit_dentry = false;237		dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl);238		if (!dentry) {239			dfi->file_info.flags |= CEPH_F_ATEND;240			err = 0;241			break;242		}243		if (IS_ERR(dentry)) {244			err = PTR_ERR(dentry);245			goto out;246		}247 248		spin_lock(&dentry->d_lock);249		di = ceph_dentry(dentry);250		if (d_unhashed(dentry) ||251		    d_really_is_negative(dentry) ||252		    di->lease_shared_gen != shared_gen ||253		    ((dentry->d_flags & DCACHE_NOKEY_NAME) &&254		     fscrypt_has_encryption_key(dir))) {255			spin_unlock(&dentry->d_lock);256			dput(dentry);257			err = -EAGAIN;258			goto out;259		}260		if (fpos_cmp(ctx->pos, di->offset) <= 0) {261			__ceph_dentry_dir_lease_touch(di);262			emit_dentry = true;263		}264		spin_unlock(&dentry->d_lock);265 266		if (emit_dentry) {267			doutc(cl, " %llx dentry %p %pd %p\n", di->offset,268			      dentry, dentry, d_inode(dentry));269			ctx->pos = di->offset;270			if (!dir_emit(ctx, dentry->d_name.name,271				      dentry->d_name.len, ceph_present_inode(d_inode(dentry)),272				      d_inode(dentry)->i_mode >> 12)) {273				dput(dentry);274				err = 0;275				break;276			}277			ctx->pos++;278 279			if (last)280				dput(last);281			last = dentry;282		} else {283			dput(dentry);284		}285	}286out:287	ceph_readdir_cache_release(&cache_ctl);288	if (last) {289		int ret;290		di = ceph_dentry(last);291		ret = note_last_dentry(fsc, dfi, last->d_name.name,292				       last->d_name.len,293				       fpos_off(di->offset) + 1);294		if (ret < 0)295			err = ret;296		dput(last);297		/* last_name no longer match cache index */298		if (dfi->readdir_cache_idx >= 0) {299			dfi->readdir_cache_idx = -1;300			dfi->dir_release_count = 0;301		}302	}303	return err;304}305 306static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos)307{308	if (!dfi->last_readdir)309		return true;310	if (is_hash_order(pos))311		return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos));312	else313		return dfi->frag != fpos_frag(pos);314}315 316static int ceph_readdir(struct file *file, struct dir_context *ctx)317{318	struct ceph_dir_file_info *dfi = file->private_data;319	struct inode *inode = file_inode(file);320	struct ceph_inode_info *ci = ceph_inode(inode);321	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);322	struct ceph_mds_client *mdsc = fsc->mdsc;323	struct ceph_client *cl = fsc->client;324	int i;325	int err;326	unsigned frag = -1;327	struct ceph_mds_reply_info_parsed *rinfo;328 329	doutc(cl, "%p %llx.%llx file %p pos %llx\n", inode,330	      ceph_vinop(inode), file, ctx->pos);331	if (dfi->file_info.flags & CEPH_F_ATEND)332		return 0;333 334	/* always start with . and .. */335	if (ctx->pos == 0) {336		doutc(cl, "%p %llx.%llx off 0 -> '.'\n", inode,337		      ceph_vinop(inode));338		if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode),339			    inode->i_mode >> 12))340			return 0;341		ctx->pos = 1;342	}343	if (ctx->pos == 1) {344		u64 ino;345		struct dentry *dentry = file->f_path.dentry;346 347		spin_lock(&dentry->d_lock);348		ino = ceph_present_inode(dentry->d_parent->d_inode);349		spin_unlock(&dentry->d_lock);350 351		doutc(cl, "%p %llx.%llx off 1 -> '..'\n", inode,352		      ceph_vinop(inode));353		if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12))354			return 0;355		ctx->pos = 2;356	}357 358	err = ceph_fscrypt_prepare_readdir(inode);359	if (err < 0)360		return err;361 362	spin_lock(&ci->i_ceph_lock);363	/* request Fx cap. if have Fx, we don't need to release Fs cap364	 * for later create/unlink. */365	__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR);366	/* can we use the dcache? */367	if (ceph_test_mount_opt(fsc, DCACHE) &&368	    !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&369	    ceph_snap(inode) != CEPH_SNAPDIR &&370	    __ceph_dir_is_complete_ordered(ci) &&371	    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {372		int shared_gen = atomic_read(&ci->i_shared_gen);373 374		spin_unlock(&ci->i_ceph_lock);375		err = __dcache_readdir(file, ctx, shared_gen);376		if (err != -EAGAIN)377			return err;378	} else {379		spin_unlock(&ci->i_ceph_lock);380	}381 382	/* proceed with a normal readdir */383more:384	/* do we have the correct frag content buffered? */385	if (need_send_readdir(dfi, ctx->pos)) {386		struct ceph_mds_request *req;387		int op = ceph_snap(inode) == CEPH_SNAPDIR ?388			CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;389 390		/* discard old result, if any */391		if (dfi->last_readdir) {392			ceph_mdsc_put_request(dfi->last_readdir);393			dfi->last_readdir = NULL;394		}395 396		if (is_hash_order(ctx->pos)) {397			/* fragtree isn't always accurate. choose frag398			 * based on previous reply when possible. */399			if (frag == (unsigned)-1)400				frag = ceph_choose_frag(ci, fpos_hash(ctx->pos),401							NULL, NULL);402		} else {403			frag = fpos_frag(ctx->pos);404		}405 406		doutc(cl, "fetching %p %llx.%llx frag %x offset '%s'\n",407		      inode, ceph_vinop(inode), frag, dfi->last_name);408		req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);409		if (IS_ERR(req))410			return PTR_ERR(req);411 412		err = ceph_alloc_readdir_reply_buffer(req, inode);413		if (err) {414			ceph_mdsc_put_request(req);415			return err;416		}417		/* hints to request -> mds selection code */418		req->r_direct_mode = USE_AUTH_MDS;419		if (op == CEPH_MDS_OP_READDIR) {420			req->r_direct_hash = ceph_frag_value(frag);421			__set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags);422			req->r_inode_drop = CEPH_CAP_FILE_EXCL;423		}424		if (dfi->last_name) {425			struct qstr d_name = { .name = dfi->last_name,426					       .len = strlen(dfi->last_name) };427 428			req->r_path2 = kzalloc(NAME_MAX + 1, GFP_KERNEL);429			if (!req->r_path2) {430				ceph_mdsc_put_request(req);431				return -ENOMEM;432			}433 434			err = ceph_encode_encrypted_dname(inode, &d_name,435							  req->r_path2);436			if (err < 0) {437				ceph_mdsc_put_request(req);438				return err;439			}440		} else if (is_hash_order(ctx->pos)) {441			req->r_args.readdir.offset_hash =442				cpu_to_le32(fpos_hash(ctx->pos));443		}444 445		req->r_dir_release_cnt = dfi->dir_release_count;446		req->r_dir_ordered_cnt = dfi->dir_ordered_count;447		req->r_readdir_cache_idx = dfi->readdir_cache_idx;448		req->r_readdir_offset = dfi->next_offset;449		req->r_args.readdir.frag = cpu_to_le32(frag);450		req->r_args.readdir.flags =451				cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS);452 453		req->r_inode = inode;454		ihold(inode);455		req->r_dentry = dget(file->f_path.dentry);456		err = ceph_mdsc_do_request(mdsc, NULL, req);457		if (err < 0) {458			ceph_mdsc_put_request(req);459			return err;460		}461		doutc(cl, "%p %llx.%llx got and parsed readdir result=%d"462		      "on frag %x, end=%d, complete=%d, hash_order=%d\n",463		      inode, ceph_vinop(inode), err, frag,464		      (int)req->r_reply_info.dir_end,465		      (int)req->r_reply_info.dir_complete,466		      (int)req->r_reply_info.hash_order);467 468		rinfo = &req->r_reply_info;469		if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {470			frag = le32_to_cpu(rinfo->dir_dir->frag);471			if (!rinfo->hash_order) {472				dfi->next_offset = req->r_readdir_offset;473				/* adjust ctx->pos to beginning of frag */474				ctx->pos = ceph_make_fpos(frag,475							  dfi->next_offset,476							  false);477			}478		}479 480		dfi->frag = frag;481		dfi->last_readdir = req;482 483		if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) {484			dfi->readdir_cache_idx = req->r_readdir_cache_idx;485			if (dfi->readdir_cache_idx < 0) {486				/* preclude from marking dir ordered */487				dfi->dir_ordered_count = 0;488			} else if (ceph_frag_is_leftmost(frag) &&489				   dfi->next_offset == 2) {490				/* note dir version at start of readdir so491				 * we can tell if any dentries get dropped */492				dfi->dir_release_count = req->r_dir_release_cnt;493				dfi->dir_ordered_count = req->r_dir_ordered_cnt;494			}495		} else {496			doutc(cl, "%p %llx.%llx !did_prepopulate\n", inode,497			      ceph_vinop(inode));498			/* disable readdir cache */499			dfi->readdir_cache_idx = -1;500			/* preclude from marking dir complete */501			dfi->dir_release_count = 0;502		}503 504		/* note next offset and last dentry name */505		if (rinfo->dir_nr > 0) {506			struct ceph_mds_reply_dir_entry *rde =507					rinfo->dir_entries + (rinfo->dir_nr-1);508			unsigned next_offset = req->r_reply_info.dir_end ?509					2 : (fpos_off(rde->offset) + 1);510			err = note_last_dentry(fsc, dfi, rde->name,511					       rde->name_len, next_offset);512			if (err) {513				ceph_mdsc_put_request(dfi->last_readdir);514				dfi->last_readdir = NULL;515				return err;516			}517		} else if (req->r_reply_info.dir_end) {518			dfi->next_offset = 2;519			/* keep last name */520		}521	}522 523	rinfo = &dfi->last_readdir->r_reply_info;524	doutc(cl, "%p %llx.%llx frag %x num %d pos %llx chunk first %llx\n",525	      inode, ceph_vinop(inode), dfi->frag, rinfo->dir_nr, ctx->pos,526	      rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL);527 528	i = 0;529	/* search start position */530	if (rinfo->dir_nr > 0) {531		int step, nr = rinfo->dir_nr;532		while (nr > 0) {533			step = nr >> 1;534			if (rinfo->dir_entries[i + step].offset < ctx->pos) {535				i +=  step + 1;536				nr -= step + 1;537			} else {538				nr = step;539			}540		}541	}542	for (; i < rinfo->dir_nr; i++) {543		struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;544 545		if (rde->offset < ctx->pos) {546			pr_warn_client(cl,547				"%p %llx.%llx rde->offset 0x%llx ctx->pos 0x%llx\n",548				inode, ceph_vinop(inode), rde->offset, ctx->pos);549			return -EIO;550		}551 552		if (WARN_ON_ONCE(!rde->inode.in))553			return -EIO;554 555		ctx->pos = rde->offset;556		doutc(cl, "%p %llx.%llx (%d/%d) -> %llx '%.*s' %p\n", inode,557		      ceph_vinop(inode), i, rinfo->dir_nr, ctx->pos,558		      rde->name_len, rde->name, &rde->inode.in);559 560		if (!dir_emit(ctx, rde->name, rde->name_len,561			      ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)),562			      le32_to_cpu(rde->inode.in->mode) >> 12)) {563			/*564			 * NOTE: Here no need to put the 'dfi->last_readdir',565			 * because when dir_emit stops us it's most likely566			 * doesn't have enough memory, etc. So for next readdir567			 * it will continue.568			 */569			doutc(cl, "filldir stopping us...\n");570			return 0;571		}572 573		/* Reset the lengths to their original allocated vals */574		ctx->pos++;575	}576 577	ceph_mdsc_put_request(dfi->last_readdir);578	dfi->last_readdir = NULL;579 580	if (dfi->next_offset > 2) {581		frag = dfi->frag;582		goto more;583	}584 585	/* more frags? */586	if (!ceph_frag_is_rightmost(dfi->frag)) {587		frag = ceph_frag_next(dfi->frag);588		if (is_hash_order(ctx->pos)) {589			loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag),590							dfi->next_offset, true);591			if (new_pos > ctx->pos)592				ctx->pos = new_pos;593			/* keep last_name */594		} else {595			ctx->pos = ceph_make_fpos(frag, dfi->next_offset,596							false);597			kfree(dfi->last_name);598			dfi->last_name = NULL;599		}600		doutc(cl, "%p %llx.%llx next frag is %x\n", inode,601		      ceph_vinop(inode), frag);602		goto more;603	}604	dfi->file_info.flags |= CEPH_F_ATEND;605 606	/*607	 * if dir_release_count still matches the dir, no dentries608	 * were released during the whole readdir, and we should have609	 * the complete dir contents in our cache.610	 */611	if (atomic64_read(&ci->i_release_count) ==612					dfi->dir_release_count) {613		spin_lock(&ci->i_ceph_lock);614		if (dfi->dir_ordered_count ==615				atomic64_read(&ci->i_ordered_count)) {616			doutc(cl, " marking %p %llx.%llx complete and ordered\n",617			      inode, ceph_vinop(inode));618			/* use i_size to track number of entries in619			 * readdir cache */620			BUG_ON(dfi->readdir_cache_idx < 0);621			i_size_write(inode, dfi->readdir_cache_idx *622				     sizeof(struct dentry*));623		} else {624			doutc(cl, " marking %llx.%llx complete\n",625			      ceph_vinop(inode));626		}627		__ceph_dir_set_complete(ci, dfi->dir_release_count,628					dfi->dir_ordered_count);629		spin_unlock(&ci->i_ceph_lock);630	}631	doutc(cl, "%p %llx.%llx file %p done.\n", inode, ceph_vinop(inode),632	      file);633	return 0;634}635 636static void reset_readdir(struct ceph_dir_file_info *dfi)637{638	if (dfi->last_readdir) {639		ceph_mdsc_put_request(dfi->last_readdir);640		dfi->last_readdir = NULL;641	}642	kfree(dfi->last_name);643	dfi->last_name = NULL;644	dfi->dir_release_count = 0;645	dfi->readdir_cache_idx = -1;646	dfi->next_offset = 2;  /* compensate for . and .. */647	dfi->file_info.flags &= ~CEPH_F_ATEND;648}649 650/*651 * discard buffered readdir content on seekdir(0), or seek to new frag,652 * or seek prior to current chunk653 */654static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos)655{656	struct ceph_mds_reply_info_parsed *rinfo;657	loff_t chunk_offset;658	if (new_pos == 0)659		return true;660	if (is_hash_order(new_pos)) {661		/* no need to reset last_name for a forward seek when662		 * dentries are sotred in hash order */663	} else if (dfi->frag != fpos_frag(new_pos)) {664		return true;665	}666	rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL;667	if (!rinfo || !rinfo->dir_nr)668		return true;669	chunk_offset = rinfo->dir_entries[0].offset;670	return new_pos < chunk_offset ||671	       is_hash_order(new_pos) != is_hash_order(chunk_offset);672}673 674static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)675{676	struct ceph_dir_file_info *dfi = file->private_data;677	struct inode *inode = file->f_mapping->host;678	struct ceph_client *cl = ceph_inode_to_client(inode);679	loff_t retval;680 681	inode_lock(inode);682	retval = -EINVAL;683	switch (whence) {684	case SEEK_CUR:685		offset += file->f_pos;686		break;687	case SEEK_SET:688		break;689	case SEEK_END:690		retval = -EOPNOTSUPP;691		goto out;692	default:693		goto out;694	}695 696	if (offset >= 0) {697		if (need_reset_readdir(dfi, offset)) {698			doutc(cl, "%p %llx.%llx dropping %p content\n",699			      inode, ceph_vinop(inode), file);700			reset_readdir(dfi);701		} else if (is_hash_order(offset) && offset > file->f_pos) {702			/* for hash offset, we don't know if a forward seek703			 * is within same frag */704			dfi->dir_release_count = 0;705			dfi->readdir_cache_idx = -1;706		}707 708		if (offset != file->f_pos) {709			file->f_pos = offset;710			dfi->file_info.flags &= ~CEPH_F_ATEND;711		}712		retval = offset;713	}714out:715	inode_unlock(inode);716	return retval;717}718 719/*720 * Handle lookups for the hidden .snap directory.721 */722struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,723				   struct dentry *dentry)724{725	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);726	struct inode *parent = d_inode(dentry->d_parent); /* we hold i_rwsem */727	struct ceph_client *cl = ceph_inode_to_client(parent);728 729	/* .snap dir? */730	if (ceph_snap(parent) == CEPH_NOSNAP &&731	    strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {732		struct dentry *res;733		struct inode *inode = ceph_get_snapdir(parent);734 735		res = d_splice_alias(inode, dentry);736		doutc(cl, "ENOENT on snapdir %p '%pd', linking to "737		      "snapdir %p %llx.%llx. Spliced dentry %p\n",738		      dentry, dentry, inode, ceph_vinop(inode), res);739		if (res)740			dentry = res;741	}742	return dentry;743}744 745/*746 * Figure out final result of a lookup/open request.747 *748 * Mainly, make sure we return the final req->r_dentry (if it already749 * existed) in place of the original VFS-provided dentry when they750 * differ.751 *752 * Gracefully handle the case where the MDS replies with -ENOENT and753 * no trace (which it may do, at its discretion, e.g., if it doesn't754 * care to issue a lease on the negative dentry).755 */756struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,757				  struct dentry *dentry, int err)758{759	struct ceph_client *cl = req->r_mdsc->fsc->client;760 761	if (err == -ENOENT) {762		/* no trace? */763		err = 0;764		if (!req->r_reply_info.head->is_dentry) {765			doutc(cl,766			      "ENOENT and no trace, dentry %p inode %llx.%llx\n",767			      dentry, ceph_vinop(d_inode(dentry)));768			if (d_really_is_positive(dentry)) {769				d_drop(dentry);770				err = -ENOENT;771			} else {772				d_add(dentry, NULL);773			}774		}775	}776	if (err)777		dentry = ERR_PTR(err);778	else if (dentry != req->r_dentry)779		dentry = dget(req->r_dentry);   /* we got spliced */780	else781		dentry = NULL;782	return dentry;783}784 785static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)786{787	return ceph_ino(inode) == CEPH_INO_ROOT &&788		strncmp(dentry->d_name.name, ".ceph", 5) == 0;789}790 791/*792 * Look up a single dir entry.  If there is a lookup intent, inform793 * the MDS so that it gets our 'caps wanted' value in a single op.794 */795static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,796				  unsigned int flags)797{798	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);799	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);800	struct ceph_client *cl = fsc->client;801	struct ceph_mds_request *req;802	int op;803	int mask;804	int err;805 806	doutc(cl, "%p %llx.%llx/'%pd' dentry %p\n", dir, ceph_vinop(dir),807	      dentry, dentry);808 809	if (dentry->d_name.len > NAME_MAX)810		return ERR_PTR(-ENAMETOOLONG);811 812	if (IS_ENCRYPTED(dir)) {813		bool had_key = fscrypt_has_encryption_key(dir);814 815		err = fscrypt_prepare_lookup_partial(dir, dentry);816		if (err < 0)817			return ERR_PTR(err);818 819		/* mark directory as incomplete if it has been unlocked */820		if (!had_key && fscrypt_has_encryption_key(dir))821			ceph_dir_clear_complete(dir);822	}823 824	/* can we conclude ENOENT locally? */825	if (d_really_is_negative(dentry)) {826		struct ceph_inode_info *ci = ceph_inode(dir);827		struct ceph_dentry_info *di = ceph_dentry(dentry);828 829		spin_lock(&ci->i_ceph_lock);830		doutc(cl, " dir %llx.%llx flags are 0x%lx\n",831		      ceph_vinop(dir), ci->i_ceph_flags);832		if (strncmp(dentry->d_name.name,833			    fsc->mount_options->snapdir_name,834			    dentry->d_name.len) &&835		    !is_root_ceph_dentry(dir, dentry) &&836		    ceph_test_mount_opt(fsc, DCACHE) &&837		    __ceph_dir_is_complete(ci) &&838		    __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {839			__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);840			spin_unlock(&ci->i_ceph_lock);841			doutc(cl, " dir %llx.%llx complete, -ENOENT\n",842			      ceph_vinop(dir));843			d_add(dentry, NULL);844			di->lease_shared_gen = atomic_read(&ci->i_shared_gen);845			return NULL;846		}847		spin_unlock(&ci->i_ceph_lock);848	}849 850	op = ceph_snap(dir) == CEPH_SNAPDIR ?851		CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;852	req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);853	if (IS_ERR(req))854		return ERR_CAST(req);855	req->r_dentry = dget(dentry);856	req->r_num_caps = 2;857 858	mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;859	if (ceph_security_xattr_wanted(dir))860		mask |= CEPH_CAP_XATTR_SHARED;861	req->r_args.getattr.mask = cpu_to_le32(mask);862 863	ihold(dir);864	req->r_parent = dir;865	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);866	err = ceph_mdsc_do_request(mdsc, NULL, req);867	if (err == -ENOENT) {868		struct dentry *res;869 870		res = ceph_handle_snapdir(req, dentry);871		if (IS_ERR(res)) {872			err = PTR_ERR(res);873		} else {874			dentry = res;875			err = 0;876		}877	}878	dentry = ceph_finish_lookup(req, dentry, err);879	ceph_mdsc_put_request(req);  /* will dput(dentry) */880	doutc(cl, "result=%p\n", dentry);881	return dentry;882}883 884/*885 * If we do a create but get no trace back from the MDS, follow up with886 * a lookup (the VFS expects us to link up the provided dentry).887 */888int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)889{890	struct dentry *result = ceph_lookup(dir, dentry, 0);891 892	if (result && !IS_ERR(result)) {893		/*894		 * We created the item, then did a lookup, and found895		 * it was already linked to another inode we already896		 * had in our cache (and thus got spliced). To not897		 * confuse VFS (especially when inode is a directory),898		 * we don't link our dentry to that inode, return an899		 * error instead.900		 *901		 * This event should be rare and it happens only when902		 * we talk to old MDS. Recent MDS does not send traceless903		 * reply for request that creates new inode.904		 */905		d_drop(result);906		return -ESTALE;907	}908	return PTR_ERR(result);909}910 911static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir,912		      struct dentry *dentry, umode_t mode, dev_t rdev)913{914	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);915	struct ceph_client *cl = mdsc->fsc->client;916	struct ceph_mds_request *req;917	struct ceph_acl_sec_ctx as_ctx = {};918	int err;919 920	if (ceph_snap(dir) != CEPH_NOSNAP)921		return -EROFS;922 923	err = ceph_wait_on_conflict_unlink(dentry);924	if (err)925		return err;926 927	if (ceph_quota_is_max_files_exceeded(dir)) {928		err = -EDQUOT;929		goto out;930	}931 932	doutc(cl, "%p %llx.%llx/'%pd' dentry %p mode 0%ho rdev %d\n",933	      dir, ceph_vinop(dir), dentry, dentry, mode, rdev);934	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);935	if (IS_ERR(req)) {936		err = PTR_ERR(req);937		goto out;938	}939 940	req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);941	if (IS_ERR(req->r_new_inode)) {942		err = PTR_ERR(req->r_new_inode);943		req->r_new_inode = NULL;944		goto out_req;945	}946 947	if (S_ISREG(mode) && IS_ENCRYPTED(dir))948		set_bit(CEPH_MDS_R_FSCRYPT_FILE, &req->r_req_flags);949 950	req->r_dentry = dget(dentry);951	req->r_num_caps = 2;952	req->r_parent = dir;953	ihold(dir);954	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);955	req->r_mnt_idmap = mnt_idmap_get(idmap);956	req->r_args.mknod.mode = cpu_to_le32(mode);957	req->r_args.mknod.rdev = cpu_to_le32(rdev);958	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |959			     CEPH_CAP_XATTR_EXCL;960	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;961 962	ceph_as_ctx_to_req(req, &as_ctx);963 964	err = ceph_mdsc_do_request(mdsc, dir, req);965	if (!err && !req->r_reply_info.head->is_dentry)966		err = ceph_handle_notrace_create(dir, dentry);967out_req:968	ceph_mdsc_put_request(req);969out:970	if (!err)971		ceph_init_inode_acls(d_inode(dentry), &as_ctx);972	else973		d_drop(dentry);974	ceph_release_acl_sec_ctx(&as_ctx);975	return err;976}977 978static int ceph_create(struct mnt_idmap *idmap, struct inode *dir,979		       struct dentry *dentry, umode_t mode, bool excl)980{981	return ceph_mknod(idmap, dir, dentry, mode, 0);982}983 984#if IS_ENABLED(CONFIG_FS_ENCRYPTION)985static int prep_encrypted_symlink_target(struct ceph_mds_request *req,986					 const char *dest)987{988	int err;989	int len = strlen(dest);990	struct fscrypt_str osd_link = FSTR_INIT(NULL, 0);991 992	err = fscrypt_prepare_symlink(req->r_parent, dest, len, PATH_MAX,993				      &osd_link);994	if (err)995		goto out;996 997	err = fscrypt_encrypt_symlink(req->r_new_inode, dest, len, &osd_link);998	if (err)999		goto out;1000 1001	req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL);1002	if (!req->r_path2) {1003		err = -ENOMEM;1004		goto out;1005	}1006 1007	len = ceph_base64_encode(osd_link.name, osd_link.len, req->r_path2);1008	req->r_path2[len] = '\0';1009out:1010	fscrypt_fname_free_buffer(&osd_link);1011	return err;1012}1013#else1014static int prep_encrypted_symlink_target(struct ceph_mds_request *req,1015					 const char *dest)1016{1017	return -EOPNOTSUPP;1018}1019#endif1020 1021static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir,1022			struct dentry *dentry, const char *dest)1023{1024	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);1025	struct ceph_client *cl = mdsc->fsc->client;1026	struct ceph_mds_request *req;1027	struct ceph_acl_sec_ctx as_ctx = {};1028	umode_t mode = S_IFLNK | 0777;1029	int err;1030 1031	if (ceph_snap(dir) != CEPH_NOSNAP)1032		return -EROFS;1033 1034	err = ceph_wait_on_conflict_unlink(dentry);1035	if (err)1036		return err;1037 1038	if (ceph_quota_is_max_files_exceeded(dir)) {1039		err = -EDQUOT;1040		goto out;1041	}1042 1043	doutc(cl, "%p %llx.%llx/'%pd' to '%s'\n", dir, ceph_vinop(dir), dentry,1044	      dest);1045	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);1046	if (IS_ERR(req)) {1047		err = PTR_ERR(req);1048		goto out;1049	}1050 1051	req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);1052	if (IS_ERR(req->r_new_inode)) {1053		err = PTR_ERR(req->r_new_inode);1054		req->r_new_inode = NULL;1055		goto out_req;1056	}1057 1058	req->r_parent = dir;1059	ihold(dir);1060 1061	if (IS_ENCRYPTED(req->r_new_inode)) {1062		err = prep_encrypted_symlink_target(req, dest);1063		if (err)1064			goto out_req;1065	} else {1066		req->r_path2 = kstrdup(dest, GFP_KERNEL);1067		if (!req->r_path2) {1068			err = -ENOMEM;1069			goto out_req;1070		}1071	}1072 1073	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);1074	req->r_mnt_idmap = mnt_idmap_get(idmap);1075	req->r_dentry = dget(dentry);1076	req->r_num_caps = 2;1077	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |1078			     CEPH_CAP_XATTR_EXCL;1079	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;1080 1081	ceph_as_ctx_to_req(req, &as_ctx);1082 1083	err = ceph_mdsc_do_request(mdsc, dir, req);1084	if (!err && !req->r_reply_info.head->is_dentry)1085		err = ceph_handle_notrace_create(dir, dentry);1086out_req:1087	ceph_mdsc_put_request(req);1088out:1089	if (err)1090		d_drop(dentry);1091	ceph_release_acl_sec_ctx(&as_ctx);1092	return err;1093}1094 1095static int ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir,1096		      struct dentry *dentry, umode_t mode)1097{1098	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);1099	struct ceph_client *cl = mdsc->fsc->client;1100	struct ceph_mds_request *req;1101	struct ceph_acl_sec_ctx as_ctx = {};1102	int err;1103	int op;1104 1105	err = ceph_wait_on_conflict_unlink(dentry);1106	if (err)1107		return err;1108 1109	if (ceph_snap(dir) == CEPH_SNAPDIR) {1110		/* mkdir .snap/foo is a MKSNAP */1111		op = CEPH_MDS_OP_MKSNAP;1112		doutc(cl, "mksnap %llx.%llx/'%pd' dentry %p\n",1113		      ceph_vinop(dir), dentry, dentry);1114	} else if (ceph_snap(dir) == CEPH_NOSNAP) {1115		doutc(cl, "mkdir %llx.%llx/'%pd' dentry %p mode 0%ho\n",1116		      ceph_vinop(dir), dentry, dentry, mode);1117		op = CEPH_MDS_OP_MKDIR;1118	} else {1119		err = -EROFS;1120		goto out;1121	}1122 1123	if (op == CEPH_MDS_OP_MKDIR &&1124	    ceph_quota_is_max_files_exceeded(dir)) {1125		err = -EDQUOT;1126		goto out;1127	}1128	if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) &&1129	    !fscrypt_has_encryption_key(dir)) {1130		err = -ENOKEY;1131		goto out;1132	}1133 1134 1135	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);1136	if (IS_ERR(req)) {1137		err = PTR_ERR(req);1138		goto out;1139	}1140 1141	mode |= S_IFDIR;1142	req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx);1143	if (IS_ERR(req->r_new_inode)) {1144		err = PTR_ERR(req->r_new_inode);1145		req->r_new_inode = NULL;1146		goto out_req;1147	}1148 1149	req->r_dentry = dget(dentry);1150	req->r_num_caps = 2;1151	req->r_parent = dir;1152	ihold(dir);1153	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);1154	if (op == CEPH_MDS_OP_MKDIR)1155		req->r_mnt_idmap = mnt_idmap_get(idmap);1156	req->r_args.mkdir.mode = cpu_to_le32(mode);1157	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL |1158			     CEPH_CAP_XATTR_EXCL;1159	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;1160 1161	ceph_as_ctx_to_req(req, &as_ctx);1162 1163	err = ceph_mdsc_do_request(mdsc, dir, req);1164	if (!err &&1165	    !req->r_reply_info.head->is_target &&1166	    !req->r_reply_info.head->is_dentry)1167		err = ceph_handle_notrace_create(dir, dentry);1168out_req:1169	ceph_mdsc_put_request(req);1170out:1171	if (!err)1172		ceph_init_inode_acls(d_inode(dentry), &as_ctx);1173	else1174		d_drop(dentry);1175	ceph_release_acl_sec_ctx(&as_ctx);1176	return err;1177}1178 1179static int ceph_link(struct dentry *old_dentry, struct inode *dir,1180		     struct dentry *dentry)1181{1182	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);1183	struct ceph_client *cl = mdsc->fsc->client;1184	struct ceph_mds_request *req;1185	int err;1186 1187	if (dentry->d_flags & DCACHE_DISCONNECTED)1188		return -EINVAL;1189 1190	err = ceph_wait_on_conflict_unlink(dentry);1191	if (err)1192		return err;1193 1194	if (ceph_snap(dir) != CEPH_NOSNAP)1195		return -EROFS;1196 1197	err = fscrypt_prepare_link(old_dentry, dir, dentry);1198	if (err)1199		return err;1200 1201	doutc(cl, "%p %llx.%llx/'%pd' to '%pd'\n", dir, ceph_vinop(dir),1202	      old_dentry, dentry);1203	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);1204	if (IS_ERR(req)) {1205		d_drop(dentry);1206		return PTR_ERR(req);1207	}1208	req->r_dentry = dget(dentry);1209	req->r_num_caps = 2;1210	req->r_old_dentry = dget(old_dentry);1211	/*1212	 * The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we1213	 * will just pass the ino# to MDSs.1214	 */1215	if (old_dentry->d_flags & DCACHE_DISCONNECTED)1216		req->r_ino2 = ceph_vino(d_inode(old_dentry));1217	req->r_parent = dir;1218	ihold(dir);1219	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);1220	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;1221	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;1222	/* release LINK_SHARED on source inode (mds will lock it) */1223	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;1224	err = ceph_mdsc_do_request(mdsc, dir, req);1225	if (err) {1226		d_drop(dentry);1227	} else if (!req->r_reply_info.head->is_dentry) {1228		ihold(d_inode(old_dentry));1229		d_instantiate(dentry, d_inode(old_dentry));1230	}1231	ceph_mdsc_put_request(req);1232	return err;1233}1234 1235static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc,1236				 struct ceph_mds_request *req)1237{1238	struct dentry *dentry = req->r_dentry;1239	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);1240	struct ceph_client *cl = fsc->client;1241	struct ceph_dentry_info *di = ceph_dentry(dentry);1242	int result = req->r_err ? req->r_err :1243			le32_to_cpu(req->r_reply_info.head->result);1244 1245	if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags))1246		pr_warn_client(cl,1247			"dentry %p:%pd async unlink bit is not set\n",1248			dentry, dentry);1249 1250	spin_lock(&fsc->async_unlink_conflict_lock);1251	hash_del_rcu(&di->hnode);1252	spin_unlock(&fsc->async_unlink_conflict_lock);1253 1254	spin_lock(&dentry->d_lock);1255	di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;1256	wake_up_bit(&di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT);1257	spin_unlock(&dentry->d_lock);1258 1259	synchronize_rcu();1260 1261	if (result == -EJUKEBOX)1262		goto out;1263 1264	/* If op failed, mark everyone involved for errors */1265	if (result) {1266		int pathlen = 0;1267		u64 base = 0;1268		char *path = ceph_mdsc_build_path(mdsc, dentry, &pathlen,1269						  &base, 0);1270 1271		/* mark error on parent + clear complete */1272		mapping_set_error(req->r_parent->i_mapping, result);1273		ceph_dir_clear_complete(req->r_parent);1274 1275		/* drop the dentry -- we don't know its status */1276		if (!d_unhashed(dentry))1277			d_drop(dentry);1278 1279		/* mark inode itself for an error (since metadata is bogus) */1280		mapping_set_error(req->r_old_inode->i_mapping, result);1281 1282		pr_warn_client(cl, "failure path=(%llx)%s result=%d!\n",1283			       base, IS_ERR(path) ? "<<bad>>" : path, result);1284		ceph_mdsc_free_path(path, pathlen);1285	}1286out:1287	iput(req->r_old_inode);1288	ceph_mdsc_release_dir_caps(req);1289}1290 1291static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry)1292{1293	struct ceph_inode_info *ci = ceph_inode(dir);1294	struct ceph_dentry_info *di;1295	int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK;1296 1297	spin_lock(&ci->i_ceph_lock);1298	if ((__ceph_caps_issued(ci, NULL) & want) == want) {1299		ceph_take_cap_refs(ci, want, false);1300		got = want;1301	}1302	spin_unlock(&ci->i_ceph_lock);1303 1304	/* If we didn't get anything, return 0 */1305	if (!got)1306		return 0;1307 1308        spin_lock(&dentry->d_lock);1309        di = ceph_dentry(dentry);1310	/*1311	 * - We are holding Fx, which implies Fs caps.1312	 * - Only support async unlink for primary linkage1313	 */1314	if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen ||1315	    !(di->flags & CEPH_DENTRY_PRIMARY_LINK))1316		want = 0;1317        spin_unlock(&dentry->d_lock);1318 1319	/* Do we still want what we've got? */1320	if (want == got)1321		return got;1322 1323	ceph_put_cap_refs(ci, got);1324	return 0;1325}1326 1327/*1328 * rmdir and unlink are differ only by the metadata op code1329 */1330static int ceph_unlink(struct inode *dir, struct dentry *dentry)1331{1332	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dir->i_sb);1333	struct ceph_client *cl = fsc->client;1334	struct ceph_mds_client *mdsc = fsc->mdsc;1335	struct inode *inode = d_inode(dentry);1336	struct ceph_mds_request *req;1337	bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS);1338	struct dentry *dn;1339	int err = -EROFS;1340	int op;1341	char *path;1342	int pathlen;1343	u64 pathbase;1344 1345	if (ceph_snap(dir) == CEPH_SNAPDIR) {1346		/* rmdir .snap/foo is RMSNAP */1347		doutc(cl, "rmsnap %llx.%llx/'%pd' dn\n", ceph_vinop(dir),1348		      dentry);1349		op = CEPH_MDS_OP_RMSNAP;1350	} else if (ceph_snap(dir) == CEPH_NOSNAP) {1351		doutc(cl, "unlink/rmdir %llx.%llx/'%pd' inode %llx.%llx\n",1352		      ceph_vinop(dir), dentry, ceph_vinop(inode));1353		op = d_is_dir(dentry) ?1354			CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;1355	} else1356		goto out;1357 1358	dn = d_find_alias(dir);1359	if (!dn) {1360		try_async = false;1361	} else {1362		path = ceph_mdsc_build_path(mdsc, dn, &pathlen, &pathbase, 0);1363		if (IS_ERR(path)) {1364			try_async = false;1365			err = 0;1366		} else {1367			err = ceph_mds_check_access(mdsc, path, MAY_WRITE);1368		}1369		ceph_mdsc_free_path(path, pathlen);1370		dput(dn);1371 1372		/* For none EACCES cases will let the MDS do the mds auth check */1373		if (err == -EACCES) {1374			return err;1375		} else if (err < 0) {1376			try_async = false;1377			err = 0;1378		}1379	}1380 1381retry:1382	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);1383	if (IS_ERR(req)) {1384		err = PTR_ERR(req);1385		goto out;1386	}1387	req->r_dentry = dget(dentry);1388	req->r_num_caps = 2;1389	req->r_parent = dir;1390	ihold(dir);1391	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;1392	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;1393	req->r_inode_drop = ceph_drop_caps_for_unlink(inode);1394 1395	if (try_async && op == CEPH_MDS_OP_UNLINK &&1396	    (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) {1397		struct ceph_dentry_info *di = ceph_dentry(dentry);1398 1399		doutc(cl, "async unlink on %llx.%llx/'%pd' caps=%s",1400		      ceph_vinop(dir), dentry,1401		      ceph_cap_string(req->r_dir_caps));1402		set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags);1403		req->r_callback = ceph_async_unlink_cb;1404		req->r_old_inode = d_inode(dentry);1405		ihold(req->r_old_inode);1406 1407		spin_lock(&dentry->d_lock);1408		di->flags |= CEPH_DENTRY_ASYNC_UNLINK;1409		spin_unlock(&dentry->d_lock);1410 1411		spin_lock(&fsc->async_unlink_conflict_lock);1412		hash_add_rcu(fsc->async_unlink_conflict, &di->hnode,1413			     dentry->d_name.hash);1414		spin_unlock(&fsc->async_unlink_conflict_lock);1415 1416		err = ceph_mdsc_submit_request(mdsc, dir, req);1417		if (!err) {1418			/*1419			 * We have enough caps, so we assume that the unlink1420			 * will succeed. Fix up the target inode and dcache.1421			 */1422			drop_nlink(inode);1423			d_delete(dentry);1424		} else {1425			spin_lock(&fsc->async_unlink_conflict_lock);1426			hash_del_rcu(&di->hnode);1427			spin_unlock(&fsc->async_unlink_conflict_lock);1428 1429			spin_lock(&dentry->d_lock);1430			di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK;1431			spin_unlock(&dentry->d_lock);1432 1433			if (err == -EJUKEBOX) {1434				try_async = false;1435				ceph_mdsc_put_request(req);1436				goto retry;1437			}1438		}1439	} else {1440		set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);1441		err = ceph_mdsc_do_request(mdsc, dir, req);1442		if (!err && !req->r_reply_info.head->is_dentry)1443			d_delete(dentry);1444	}1445 1446	ceph_mdsc_put_request(req);1447out:1448	return err;1449}1450 1451static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir,1452		       struct dentry *old_dentry, struct inode *new_dir,1453		       struct dentry *new_dentry, unsigned int flags)1454{1455	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb);1456	struct ceph_client *cl = mdsc->fsc->client;1457	struct ceph_mds_request *req;1458	int op = CEPH_MDS_OP_RENAME;1459	int err;1460 1461	if (flags)1462		return -EINVAL;1463 1464	if (ceph_snap(old_dir) != ceph_snap(new_dir))1465		return -EXDEV;1466	if (ceph_snap(old_dir) != CEPH_NOSNAP) {1467		if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)1468			op = CEPH_MDS_OP_RENAMESNAP;1469		else1470			return -EROFS;1471	}1472	/* don't allow cross-quota renames */1473	if ((old_dir != new_dir) &&1474	    (!ceph_quota_is_same_realm(old_dir, new_dir)))1475		return -EXDEV;1476 1477	err = ceph_wait_on_conflict_unlink(new_dentry);1478	if (err)1479		return err;1480 1481	err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,1482				     flags);1483	if (err)1484		return err;1485 1486	doutc(cl, "%llx.%llx/'%pd' to %llx.%llx/'%pd'\n",1487	      ceph_vinop(old_dir), old_dentry, ceph_vinop(new_dir),1488	      new_dentry);1489	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);1490	if (IS_ERR(req))1491		return PTR_ERR(req);1492	ihold(old_dir);1493	req->r_dentry = dget(new_dentry);1494	req->r_num_caps = 2;1495	req->r_old_dentry = dget(old_dentry);1496	req->r_old_dentry_dir = old_dir;1497	req->r_parent = new_dir;1498	ihold(new_dir);1499	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);1500	req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;1501	req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;1502	req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL;1503	req->r_dentry_unless = CEPH_CAP_FILE_EXCL;1504	/* release LINK_RDCACHE on source inode (mds will lock it) */1505	req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;1506	if (d_really_is_positive(new_dentry)) {1507		req->r_inode_drop =1508			ceph_drop_caps_for_unlink(d_inode(new_dentry));1509	}1510	err = ceph_mdsc_do_request(mdsc, old_dir, req);1511	if (!err && !req->r_reply_info.head->is_dentry) {1512		/*1513		 * Normally d_move() is done by fill_trace (called by1514		 * do_request, above).  If there is no trace, we need1515		 * to do it here.1516		 */1517		d_move(old_dentry, new_dentry);1518	}1519	ceph_mdsc_put_request(req);1520	return err;1521}1522 1523/*1524 * Move dentry to tail of mdsc->dentry_leases list when lease is updated.1525 * Leases at front of the list will expire first. (Assume all leases have1526 * similar duration)1527 *1528 * Called under dentry->d_lock.1529 */1530void __ceph_dentry_lease_touch(struct ceph_dentry_info *di)1531{1532	struct dentry *dn = di->dentry;1533	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;1534	struct ceph_client *cl = mdsc->fsc->client;1535 1536	doutc(cl, "%p %p '%pd'\n", di, dn, dn);1537 1538	di->flags |= CEPH_DENTRY_LEASE_LIST;1539	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {1540		di->flags |= CEPH_DENTRY_REFERENCED;1541		return;1542	}1543 1544	spin_lock(&mdsc->dentry_list_lock);1545	list_move_tail(&di->lease_list, &mdsc->dentry_leases);1546	spin_unlock(&mdsc->dentry_list_lock);1547}1548 1549static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc,1550				     struct ceph_dentry_info *di)1551{1552	di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED);1553	di->lease_gen = 0;1554	di->time = jiffies;1555	list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases);1556}1557 1558/*1559 * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases1560 * list if it's not in the list, otherwise set 'referenced' flag.1561 *1562 * Called under dentry->d_lock.1563 */1564void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di)1565{1566	struct dentry *dn = di->dentry;1567	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dn->d_sb)->mdsc;1568	struct ceph_client *cl = mdsc->fsc->client;1569 1570	doutc(cl, "%p %p '%pd' (offset 0x%llx)\n", di, dn, dn, di->offset);1571 1572	if (!list_empty(&di->lease_list)) {1573		if (di->flags & CEPH_DENTRY_LEASE_LIST) {1574			/* don't remove dentry from dentry lease list1575			 * if its lease is valid */1576			if (__dentry_lease_is_valid(di))1577				return;1578		} else {1579			di->flags |= CEPH_DENTRY_REFERENCED;1580			return;1581		}1582	}1583 1584	if (di->flags & CEPH_DENTRY_SHRINK_LIST) {1585		di->flags |= CEPH_DENTRY_REFERENCED;1586		di->flags &= ~CEPH_DENTRY_LEASE_LIST;1587		return;1588	}1589 1590	spin_lock(&mdsc->dentry_list_lock);1591	__dentry_dir_lease_touch(mdsc, di);1592	spin_unlock(&mdsc->dentry_list_lock);1593}1594 1595static void __dentry_lease_unlist(struct ceph_dentry_info *di)1596{1597	struct ceph_mds_client *mdsc;1598	if (di->flags & CEPH_DENTRY_SHRINK_LIST)1599		return;1600	if (list_empty(&di->lease_list))1601		return;1602 1603	mdsc = ceph_sb_to_fs_client(di->dentry->d_sb)->mdsc;1604	spin_lock(&mdsc->dentry_list_lock);1605	list_del_init(&di->lease_list);1606	spin_unlock(&mdsc->dentry_list_lock);1607}1608 1609enum {1610	KEEP	= 0,1611	DELETE	= 1,1612	TOUCH	= 2,1613	STOP	= 4,1614};1615 1616struct ceph_lease_walk_control {1617	bool dir_lease;1618	bool expire_dir_lease;1619	unsigned long nr_to_scan;1620	unsigned long dir_lease_ttl;1621};1622 1623static int __dir_lease_check(const struct dentry *, struct ceph_lease_walk_control *);1624static int __dentry_lease_check(const struct dentry *);1625 1626static unsigned long1627__dentry_leases_walk(struct ceph_mds_client *mdsc,1628		     struct ceph_lease_walk_control *lwc)1629{1630	struct ceph_dentry_info *di, *tmp;1631	struct dentry *dentry, *last = NULL;1632	struct list_head* list;1633        LIST_HEAD(dispose);1634	unsigned long freed = 0;1635	int ret = 0;1636 1637	list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases;1638	spin_lock(&mdsc->dentry_list_lock);1639	list_for_each_entry_safe(di, tmp, list, lease_list) {1640		if (!lwc->nr_to_scan)1641			break;1642		--lwc->nr_to_scan;1643 1644		dentry = di->dentry;1645		if (last == dentry)1646			break;1647 1648		if (!spin_trylock(&dentry->d_lock))1649			continue;1650 1651		if (__lockref_is_dead(&dentry->d_lockref)) {1652			list_del_init(&di->lease_list);1653			goto next;1654		}1655 1656		if (lwc->dir_lease)1657			ret = __dir_lease_check(dentry, lwc);1658		else1659			ret = __dentry_lease_check(dentry);1660		if (ret & TOUCH) {1661			/* move it into tail of dir lease list */1662			__dentry_dir_lease_touch(mdsc, di);1663			if (!last)1664				last = dentry;1665		}1666		if (ret & DELETE) {1667			/* stale lease */1668			di->flags &= ~CEPH_DENTRY_REFERENCED;1669			if (dentry->d_lockref.count > 0) {1670				/* update_dentry_lease() will re-add1671				 * it to lease list, or1672				 * ceph_d_delete() will return 1 when1673				 * last reference is dropped */1674				list_del_init(&di->lease_list);1675			} else {1676				di->flags |= CEPH_DENTRY_SHRINK_LIST;1677				list_move_tail(&di->lease_list, &dispose);1678				dget_dlock(dentry);1679			}1680		}1681next:1682		spin_unlock(&dentry->d_lock);1683		if (ret & STOP)1684			break;1685	}1686	spin_unlock(&mdsc->dentry_list_lock);1687 1688	while (!list_empty(&dispose)) {1689		di = list_first_entry(&dispose, struct ceph_dentry_info,1690				      lease_list);1691		dentry = di->dentry;1692		spin_lock(&dentry->d_lock);1693 1694		list_del_init(&di->lease_list);1695		di->flags &= ~CEPH_DENTRY_SHRINK_LIST;1696		if (di->flags & CEPH_DENTRY_REFERENCED) {1697			spin_lock(&mdsc->dentry_list_lock);1698			if (di->flags & CEPH_DENTRY_LEASE_LIST) {1699				list_add_tail(&di->lease_list,1700					      &mdsc->dentry_leases);1701			} else {1702				__dentry_dir_lease_touch(mdsc, di);1703			}1704			spin_unlock(&mdsc->dentry_list_lock);1705		} else {1706			freed++;1707		}1708 1709		spin_unlock(&dentry->d_lock);1710		/* ceph_d_delete() does the trick */1711		dput(dentry);1712	}1713	return freed;1714}1715 1716static int __dentry_lease_check(const struct dentry *dentry)1717{1718	struct ceph_dentry_info *di = ceph_dentry(dentry);1719	int ret;1720 1721	if (__dentry_lease_is_valid(di))1722		return STOP;1723	ret = __dir_lease_try_check(dentry);1724	if (ret == -EBUSY)1725		return KEEP;1726	if (ret > 0)1727		return TOUCH;1728	return DELETE;1729}1730 1731static int __dir_lease_check(const struct dentry *dentry,1732			     struct ceph_lease_walk_control *lwc)1733{1734	struct ceph_dentry_info *di = ceph_dentry(dentry);1735 1736	int ret = __dir_lease_try_check(dentry);1737	if (ret == -EBUSY)1738		return KEEP;1739	if (ret > 0) {1740		if (time_before(jiffies, di->time + lwc->dir_lease_ttl))1741			return STOP;1742		/* Move dentry to tail of dir lease list if we don't want1743		 * to delete it. So dentries in the list are checked in a1744		 * round robin manner */1745		if (!lwc->expire_dir_lease)1746			return TOUCH;1747		if (dentry->d_lockref.count > 0 ||1748		    (di->flags & CEPH_DENTRY_REFERENCED))1749			return TOUCH;1750		/* invalidate dir lease */1751		di->lease_shared_gen = 0;1752	}1753	return DELETE;1754}1755 1756int ceph_trim_dentries(struct ceph_mds_client *mdsc)1757{1758	struct ceph_lease_walk_control lwc;1759	unsigned long count;1760	unsigned long freed;1761 1762	spin_lock(&mdsc->caps_list_lock);1763        if (mdsc->caps_use_max > 0 &&1764            mdsc->caps_use_count > mdsc->caps_use_max)1765		count = mdsc->caps_use_count - mdsc->caps_use_max;1766	else1767		count = 0;1768        spin_unlock(&mdsc->caps_list_lock);1769 1770	lwc.dir_lease = false;1771	lwc.nr_to_scan  = CEPH_CAPS_PER_RELEASE * 2;1772	freed = __dentry_leases_walk(mdsc, &lwc);1773	if (!lwc.nr_to_scan) /* more invalid leases */1774		return -EAGAIN;1775 1776	if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE)1777		lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE;1778 1779	lwc.dir_lease = true;1780	lwc.expire_dir_lease = freed < count;1781	lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ;1782	freed +=__dentry_leases_walk(mdsc, &lwc);1783	if (!lwc.nr_to_scan) /* more to check */1784		return -EAGAIN;1785 1786	return freed > 0 ? 1 : 0;1787}1788 1789/*1790 * Ensure a dentry lease will no longer revalidate.1791 */1792void ceph_invalidate_dentry_lease(struct dentry *dentry)1793{1794	struct ceph_dentry_info *di = ceph_dentry(dentry);1795	spin_lock(&dentry->d_lock);1796	di->time = jiffies;1797	di->lease_shared_gen = 0;1798	di->flags &= ~CEPH_DENTRY_PRIMARY_LINK;1799	__dentry_lease_unlist(di);1800	spin_unlock(&dentry->d_lock);1801}1802 1803/*1804 * Check if dentry lease is valid.  If not, delete the lease.  Try to1805 * renew if the least is more than half up.1806 */1807static bool __dentry_lease_is_valid(struct ceph_dentry_info *di)1808{1809	struct ceph_mds_session *session;1810 1811	if (!di->lease_gen)1812		return false;1813 1814	session = di->lease_session;1815	if (session) {1816		u32 gen;1817		unsigned long ttl;1818 1819		gen = atomic_read(&session->s_cap_gen);1820		ttl = session->s_cap_ttl;1821 1822		if (di->lease_gen == gen &&1823		    time_before(jiffies, ttl) &&1824		    time_before(jiffies, di->time))1825			return true;1826	}1827	di->lease_gen = 0;1828	return false;1829}1830 1831static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags)1832{1833	struct ceph_dentry_info *di;1834	struct ceph_mds_session *session = NULL;1835	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;1836	struct ceph_client *cl = mdsc->fsc->client;1837	u32 seq = 0;1838	int valid = 0;1839 1840	spin_lock(&dentry->d_lock);1841	di = ceph_dentry(dentry);1842	if (di && __dentry_lease_is_valid(di)) {1843		valid = 1;1844 1845		if (di->lease_renew_after &&1846		    time_after(jiffies, di->lease_renew_after)) {1847			/*1848			 * We should renew. If we're in RCU walk mode1849			 * though, we can't do that so just return1850			 * -ECHILD.1851			 */1852			if (flags & LOOKUP_RCU) {1853				valid = -ECHILD;1854			} else {1855				session = ceph_get_mds_session(di->lease_session);1856				seq = di->lease_seq;1857				di->lease_renew_after = 0;1858				di->lease_renew_from = jiffies;1859			}1860		}1861	}1862	spin_unlock(&dentry->d_lock);1863 1864	if (session) {1865		ceph_mdsc_lease_send_msg(session, dentry,1866					 CEPH_MDS_LEASE_RENEW, seq);1867		ceph_put_mds_session(session);1868	}1869	doutc(cl, "dentry %p = %d\n", dentry, valid);1870	return valid;1871}1872 1873/*1874 * Called under dentry->d_lock.1875 */1876static int __dir_lease_try_check(const struct dentry *dentry)1877{1878	struct ceph_dentry_info *di = ceph_dentry(dentry);1879	struct inode *dir;1880	struct ceph_inode_info *ci;1881	int valid = 0;1882 1883	if (!di->lease_shared_gen)1884		return 0;1885	if (IS_ROOT(dentry))1886		return 0;1887 1888	dir = d_inode(dentry->d_parent);1889	ci = ceph_inode(dir);1890 1891	if (spin_trylock(&ci->i_ceph_lock)) {1892		if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen &&1893		    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0))1894			valid = 1;1895		spin_unlock(&ci->i_ceph_lock);1896	} else {1897		valid = -EBUSY;1898	}1899 1900	if (!valid)1901		di->lease_shared_gen = 0;1902	return valid;1903}1904 1905/*1906 * Check if directory-wide content lease/cap is valid.1907 */1908static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry,1909			      struct ceph_mds_client *mdsc)1910{1911	struct ceph_inode_info *ci = ceph_inode(dir);1912	struct ceph_client *cl = mdsc->fsc->client;1913	int valid;1914	int shared_gen;1915 1916	spin_lock(&ci->i_ceph_lock);1917	valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);1918	if (valid) {1919		__ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);1920		shared_gen = atomic_read(&ci->i_shared_gen);1921	}1922	spin_unlock(&ci->i_ceph_lock);1923	if (valid) {1924		struct ceph_dentry_info *di;1925		spin_lock(&dentry->d_lock);1926		di = ceph_dentry(dentry);1927		if (dir == d_inode(dentry->d_parent) &&1928		    di && di->lease_shared_gen == shared_gen)1929			__ceph_dentry_dir_lease_touch(di);1930		else1931			valid = 0;1932		spin_unlock(&dentry->d_lock);1933	}1934	doutc(cl, "dir %p %llx.%llx v%u dentry %p '%pd' = %d\n", dir,1935	      ceph_vinop(dir), (unsigned)atomic_read(&ci->i_shared_gen),1936	      dentry, dentry, valid);1937	return valid;1938}1939 1940/*1941 * Check if cached dentry can be trusted.1942 */1943static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)1944{1945	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(dentry->d_sb)->mdsc;1946	struct ceph_client *cl = mdsc->fsc->client;1947	int valid = 0;1948	struct dentry *parent;1949	struct inode *dir, *inode;1950 1951	valid = fscrypt_d_revalidate(dentry, flags);1952	if (valid <= 0)1953		return valid;1954 1955	if (flags & LOOKUP_RCU) {1956		parent = READ_ONCE(dentry->d_parent);1957		dir = d_inode_rcu(parent);1958		if (!dir)1959			return -ECHILD;1960		inode = d_inode_rcu(dentry);1961	} else {1962		parent = dget_parent(dentry);1963		dir = d_inode(parent);1964		inode = d_inode(dentry);1965	}1966 1967	doutc(cl, "%p '%pd' inode %p offset 0x%llx nokey %d\n",1968	      dentry, dentry, inode, ceph_dentry(dentry)->offset,1969	      !!(dentry->d_flags & DCACHE_NOKEY_NAME));1970 1971	mdsc = ceph_sb_to_fs_client(dir->i_sb)->mdsc;1972 1973	/* always trust cached snapped dentries, snapdir dentry */1974	if (ceph_snap(dir) != CEPH_NOSNAP) {1975		doutc(cl, "%p '%pd' inode %p is SNAPPED\n", dentry,1976		      dentry, inode);1977		valid = 1;1978	} else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) {1979		valid = 1;1980	} else {1981		valid = dentry_lease_is_valid(dentry, flags);1982		if (valid == -ECHILD)1983			return valid;1984		if (valid || dir_lease_is_valid(dir, dentry, mdsc)) {1985			if (inode)1986				valid = ceph_is_any_caps(inode);1987			else1988				valid = 1;1989		}1990	}1991 1992	if (!valid) {1993		struct ceph_mds_request *req;1994		int op, err;1995		u32 mask;1996 1997		if (flags & LOOKUP_RCU)1998			return -ECHILD;1999 2000		percpu_counter_inc(&mdsc->metric.d_lease_mis);2001 2002		op = ceph_snap(dir) == CEPH_SNAPDIR ?2003			CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;2004		req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);2005		if (!IS_ERR(req)) {2006			req->r_dentry = dget(dentry);2007			req->r_num_caps = 2;2008			req->r_parent = dir;2009			ihold(dir);2010 2011			mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED;2012			if (ceph_security_xattr_wanted(dir))2013				mask |= CEPH_CAP_XATTR_SHARED;2014			req->r_args.getattr.mask = cpu_to_le32(mask);2015 2016			err = ceph_mdsc_do_request(mdsc, NULL, req);2017			switch (err) {2018			case 0:2019				if (d_really_is_positive(dentry) &&2020				    d_inode(dentry) == req->r_target_inode)2021					valid = 1;2022				break;2023			case -ENOENT:2024				if (d_really_is_negative(dentry))2025					valid = 1;2026				fallthrough;2027			default:2028				break;2029			}2030			ceph_mdsc_put_request(req);2031			doutc(cl, "%p '%pd', lookup result=%d\n", dentry,2032			      dentry, err);2033		}2034	} else {2035		percpu_counter_inc(&mdsc->metric.d_lease_hit);2036	}2037 2038	doutc(cl, "%p '%pd' %s\n", dentry, dentry, valid ? "valid" : "invalid");2039	if (!valid)2040		ceph_dir_clear_complete(dir);2041 2042	if (!(flags & LOOKUP_RCU))2043		dput(parent);2044	return valid;2045}2046 2047/*2048 * Delete unused dentry that doesn't have valid lease2049 *2050 * Called under dentry->d_lock.2051 */2052static int ceph_d_delete(const struct dentry *dentry)2053{2054	struct ceph_dentry_info *di;2055 2056	/* won't release caps */2057	if (d_really_is_negative(dentry))2058		return 0;2059	if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)2060		return 0;2061	/* valid lease? */2062	di = ceph_dentry(dentry);2063	if (di) {2064		if (__dentry_lease_is_valid(di))2065			return 0;2066		if (__dir_lease_try_check(dentry))2067			return 0;2068	}2069	return 1;2070}2071 2072/*2073 * Release our ceph_dentry_info.2074 */2075static void ceph_d_release(struct dentry *dentry)2076{2077	struct ceph_dentry_info *di = ceph_dentry(dentry);2078	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(dentry->d_sb);2079 2080	doutc(fsc->client, "dentry %p '%pd'\n", dentry, dentry);2081 2082	atomic64_dec(&fsc->mdsc->metric.total_dentries);2083 2084	spin_lock(&dentry->d_lock);2085	__dentry_lease_unlist(di);2086	dentry->d_fsdata = NULL;2087	spin_unlock(&dentry->d_lock);2088 2089	ceph_put_mds_session(di->lease_session);2090	kmem_cache_free(ceph_dentry_cachep, di);2091}2092 2093/*2094 * When the VFS prunes a dentry from the cache, we need to clear the2095 * complete flag on the parent directory.2096 *2097 * Called under dentry->d_lock.2098 */2099static void ceph_d_prune(struct dentry *dentry)2100{2101	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb);2102	struct ceph_client *cl = mdsc->fsc->client;2103	struct ceph_inode_info *dir_ci;2104	struct ceph_dentry_info *di;2105 2106	doutc(cl, "dentry %p '%pd'\n", dentry, dentry);2107 2108	/* do we have a valid parent? */2109	if (IS_ROOT(dentry))2110		return;2111 2112	/* we hold d_lock, so d_parent is stable */2113	dir_ci = ceph_inode(d_inode(dentry->d_parent));2114	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)2115		return;2116 2117	/* who calls d_delete() should also disable dcache readdir */2118	if (d_really_is_negative(dentry))2119		return;2120 2121	/* d_fsdata does not get cleared until d_release */2122	if (!d_unhashed(dentry)) {2123		__ceph_dir_clear_complete(dir_ci);2124		return;2125	}2126 2127	/* Disable dcache readdir just in case that someone called d_drop()2128	 * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED2129	 * properly (dcache readdir is still enabled) */2130	di = ceph_dentry(dentry);2131	if (di->offset > 0 &&2132	    di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen))2133		__ceph_dir_clear_ordered(dir_ci);2134}2135 2136/*2137 * read() on a dir.  This weird interface hack only works if mounted2138 * with '-o dirstat'.2139 */2140static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,2141			     loff_t *ppos)2142{2143	struct ceph_dir_file_info *dfi = file->private_data;2144	struct inode *inode = file_inode(file);2145	struct ceph_inode_info *ci = ceph_inode(inode);2146	int left;2147	const int bufsize = 1024;2148 2149	if (!ceph_test_mount_opt(ceph_sb_to_fs_client(inode->i_sb), DIRSTAT))2150		return -EISDIR;2151 2152	if (!dfi->dir_info) {2153		dfi->dir_info = kmalloc(bufsize, GFP_KERNEL);2154		if (!dfi->dir_info)2155			return -ENOMEM;2156		dfi->dir_info_len =2157			snprintf(dfi->dir_info, bufsize,2158				"entries:   %20lld\n"2159				" files:    %20lld\n"2160				" subdirs:  %20lld\n"2161				"rentries:  %20lld\n"2162				" rfiles:   %20lld\n"2163				" rsubdirs: %20lld\n"2164				"rbytes:    %20lld\n"2165				"rctime:    %10lld.%09ld\n",2166				ci->i_files + ci->i_subdirs,2167				ci->i_files,2168				ci->i_subdirs,2169				ci->i_rfiles + ci->i_rsubdirs,2170				ci->i_rfiles,2171				ci->i_rsubdirs,2172				ci->i_rbytes,2173				ci->i_rctime.tv_sec,2174				ci->i_rctime.tv_nsec);2175	}2176 2177	if (*ppos >= dfi->dir_info_len)2178		return 0;2179	size = min_t(unsigned, size, dfi->dir_info_len-*ppos);2180	left = copy_to_user(buf, dfi->dir_info + *ppos, size);2181	if (left == size)2182		return -EFAULT;2183	*ppos += (size - left);2184	return size - left;2185}2186 2187 2188 2189/*2190 * Return name hash for a given dentry.  This is dependent on2191 * the parent directory's hash function.2192 */2193unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)2194{2195	struct ceph_inode_info *dci = ceph_inode(dir);2196	unsigned hash;2197 2198	switch (dci->i_dir_layout.dl_dir_hash) {2199	case 0:	/* for backward compat */2200	case CEPH_STR_HASH_LINUX:2201		return dn->d_name.hash;2202 2203	default:2204		spin_lock(&dn->d_lock);2205		hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash,2206				     dn->d_name.name, dn->d_name.len);2207		spin_unlock(&dn->d_lock);2208		return hash;2209	}2210}2211 2212WRAP_DIR_ITER(ceph_readdir) // FIXME!2213const struct file_operations ceph_dir_fops = {2214	.read = ceph_read_dir,2215	.iterate_shared = shared_ceph_readdir,2216	.llseek = ceph_dir_llseek,2217	.open = ceph_open,2218	.release = ceph_release,2219	.unlocked_ioctl = ceph_ioctl,2220	.compat_ioctl = compat_ptr_ioctl,2221	.fsync = ceph_fsync,2222	.lock = ceph_lock,2223	.flock = ceph_flock,2224};2225 2226const struct file_operations ceph_snapdir_fops = {2227	.iterate_shared = shared_ceph_readdir,2228	.llseek = ceph_dir_llseek,2229	.open = ceph_open,2230	.release = ceph_release,2231};2232 2233const struct inode_operations ceph_dir_iops = {2234	.lookup = ceph_lookup,2235	.permission = ceph_permission,2236	.getattr = ceph_getattr,2237	.setattr = ceph_setattr,2238	.listxattr = ceph_listxattr,2239	.get_inode_acl = ceph_get_acl,2240	.set_acl = ceph_set_acl,2241	.mknod = ceph_mknod,2242	.symlink = ceph_symlink,2243	.mkdir = ceph_mkdir,2244	.link = ceph_link,2245	.unlink = ceph_unlink,2246	.rmdir = ceph_unlink,2247	.rename = ceph_rename,2248	.create = ceph_create,2249	.atomic_open = ceph_atomic_open,2250};2251 2252const struct inode_operations ceph_snapdir_iops = {2253	.lookup = ceph_lookup,2254	.permission = ceph_permission,2255	.getattr = ceph_getattr,2256	.mkdir = ceph_mkdir,2257	.rmdir = ceph_unlink,2258	.rename = ceph_rename,2259};2260 2261const struct dentry_operations ceph_dentry_ops = {2262	.d_revalidate = ceph_d_revalidate,2263	.d_delete = ceph_d_delete,2264	.d_release = ceph_d_release,2265	.d_prune = ceph_d_prune,2266	.d_init = ceph_d_init,2267};2268