diff options
Diffstat (limited to 'fs/ceph/dir.c')
| -rw-r--r-- | fs/ceph/dir.c | 2185 |
1 files changed, 2185 insertions, 0 deletions
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c new file mode 100644 index 0000000000..854cbdd666 --- /dev/null +++ b/fs/ceph/dir.c @@ -0,0 +1,2185 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/ceph/ceph_debug.h> + +#include <linux/spinlock.h> +#include <linux/namei.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/xattr.h> + +#include "super.h" +#include "mds_client.h" +#include "crypto.h" + +/* + * Directory operations: readdir, lookup, create, link, unlink, + * rename, etc. + */ + +/* + * Ceph MDS operations are specified in terms of a base ino and + * relative path. Thus, the client can specify an operation on a + * specific inode (e.g., a getattr due to fstat(2)), or as a path + * relative to, say, the root directory. + * + * Normally, we limit ourselves to strict inode ops (no path component) + * or dentry operations (a single path component relative to an ino). The + * exception to this is open_root_dentry(), which will open the mount + * point by name. + */ + +const struct dentry_operations ceph_dentry_ops; + +static bool __dentry_lease_is_valid(struct ceph_dentry_info *di); +static int __dir_lease_try_check(const struct dentry *dentry); + +/* + * Initialize ceph dentry state. + */ +static int ceph_d_init(struct dentry *dentry) +{ + struct ceph_dentry_info *di; + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dentry->d_sb); + + di = kmem_cache_zalloc(ceph_dentry_cachep, GFP_KERNEL); + if (!di) + return -ENOMEM; /* oh well */ + + di->dentry = dentry; + di->lease_session = NULL; + di->time = jiffies; + dentry->d_fsdata = di; + INIT_LIST_HEAD(&di->lease_list); + + atomic64_inc(&mdsc->metric.total_dentries); + + return 0; +} + +/* + * for f_pos for readdir: + * - hash order: + * (0xff << 52) | ((24 bits hash) << 28) | + * (the nth entry has hash collision); + * - frag+name order; + * ((frag value) << 28) | (the nth entry in frag); + */ +#define OFFSET_BITS 28 +#define OFFSET_MASK ((1 << OFFSET_BITS) - 1) +#define HASH_ORDER (0xffull << (OFFSET_BITS + 24)) +loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order) +{ + loff_t fpos = ((loff_t)high << 28) | (loff_t)off; + if (hash_order) + fpos |= HASH_ORDER; + return fpos; +} + +static bool is_hash_order(loff_t p) +{ + return (p & HASH_ORDER) == HASH_ORDER; +} + +static unsigned fpos_frag(loff_t p) +{ + return p >> OFFSET_BITS; +} + +static unsigned fpos_hash(loff_t p) +{ + return ceph_frag_value(fpos_frag(p)); +} + +static unsigned fpos_off(loff_t p) +{ + return p & OFFSET_MASK; +} + +static int fpos_cmp(loff_t l, loff_t r) +{ + int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r)); + if (v) + return v; + return (int)(fpos_off(l) - fpos_off(r)); +} + +/* + * make note of the last dentry we read, so we can + * continue at the same lexicographical point, + * regardless of what dir changes take place on the + * server. + */ +static int note_last_dentry(struct ceph_dir_file_info *dfi, const char *name, + int len, unsigned next_offset) +{ + char *buf = kmalloc(len+1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + kfree(dfi->last_name); + dfi->last_name = buf; + memcpy(dfi->last_name, name, len); + dfi->last_name[len] = 0; + dfi->next_offset = next_offset; + dout("note_last_dentry '%s'\n", dfi->last_name); + return 0; +} + + +static struct dentry * +__dcache_find_get_entry(struct dentry *parent, u64 idx, + struct ceph_readdir_cache_control *cache_ctl) +{ + struct inode *dir = d_inode(parent); + struct dentry *dentry; + unsigned idx_mask = (PAGE_SIZE / sizeof(struct dentry *)) - 1; + loff_t ptr_pos = idx * sizeof(struct dentry *); + pgoff_t ptr_pgoff = ptr_pos >> PAGE_SHIFT; + + if (ptr_pos >= i_size_read(dir)) + return NULL; + + if (!cache_ctl->page || ptr_pgoff != page_index(cache_ctl->page)) { + ceph_readdir_cache_release(cache_ctl); + cache_ctl->page = find_lock_page(&dir->i_data, ptr_pgoff); + if (!cache_ctl->page) { + dout(" page %lu not found\n", ptr_pgoff); + return ERR_PTR(-EAGAIN); + } + /* reading/filling the cache are serialized by + i_rwsem, no need to use page lock */ + unlock_page(cache_ctl->page); + cache_ctl->dentries = kmap(cache_ctl->page); + } + + cache_ctl->index = idx & idx_mask; + + rcu_read_lock(); + spin_lock(&parent->d_lock); + /* check i_size again here, because empty directory can be + * marked as complete while not holding the i_rwsem. */ + if (ceph_dir_is_complete_ordered(dir) && ptr_pos < i_size_read(dir)) + dentry = cache_ctl->dentries[cache_ctl->index]; + else + dentry = NULL; + spin_unlock(&parent->d_lock); + if (dentry && !lockref_get_not_dead(&dentry->d_lockref)) + dentry = NULL; + rcu_read_unlock(); + return dentry ? : ERR_PTR(-EAGAIN); +} + +/* + * When possible, we try to satisfy a readdir by peeking at the + * dcache. We make this work by carefully ordering dentries on + * d_child when we initially get results back from the MDS, and + * falling back to a "normal" sync readdir if any dentries in the dir + * are dropped. + * + * Complete dir indicates that we have all dentries in the dir. It is + * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by + * the MDS if/when the directory is modified). + */ +static int __dcache_readdir(struct file *file, struct dir_context *ctx, + int shared_gen) +{ + struct ceph_dir_file_info *dfi = file->private_data; + struct dentry *parent = file->f_path.dentry; + struct inode *dir = d_inode(parent); + struct dentry *dentry, *last = NULL; + struct ceph_dentry_info *di; + struct ceph_readdir_cache_control cache_ctl = {}; + u64 idx = 0; + int err = 0; + + dout("__dcache_readdir %p v%u at %llx\n", dir, (unsigned)shared_gen, ctx->pos); + + /* search start position */ + if (ctx->pos > 2) { + u64 count = div_u64(i_size_read(dir), sizeof(struct dentry *)); + while (count > 0) { + u64 step = count >> 1; + dentry = __dcache_find_get_entry(parent, idx + step, + &cache_ctl); + if (!dentry) { + /* use linar search */ + idx = 0; + break; + } + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto out; + } + di = ceph_dentry(dentry); + spin_lock(&dentry->d_lock); + if (fpos_cmp(di->offset, ctx->pos) < 0) { + idx += step + 1; + count -= step + 1; + } else { + count = step; + } + spin_unlock(&dentry->d_lock); + dput(dentry); + } + + dout("__dcache_readdir %p cache idx %llu\n", dir, idx); + } + + + for (;;) { + bool emit_dentry = false; + dentry = __dcache_find_get_entry(parent, idx++, &cache_ctl); + if (!dentry) { + dfi->file_info.flags |= CEPH_F_ATEND; + err = 0; + break; + } + if (IS_ERR(dentry)) { + err = PTR_ERR(dentry); + goto out; + } + + spin_lock(&dentry->d_lock); + di = ceph_dentry(dentry); + if (d_unhashed(dentry) || + d_really_is_negative(dentry) || + di->lease_shared_gen != shared_gen || + ((dentry->d_flags & DCACHE_NOKEY_NAME) && + fscrypt_has_encryption_key(dir))) { + spin_unlock(&dentry->d_lock); + dput(dentry); + err = -EAGAIN; + goto out; + } + if (fpos_cmp(ctx->pos, di->offset) <= 0) { + __ceph_dentry_dir_lease_touch(di); + emit_dentry = true; + } + spin_unlock(&dentry->d_lock); + + if (emit_dentry) { + dout(" %llx dentry %p %pd %p\n", di->offset, + dentry, dentry, d_inode(dentry)); + ctx->pos = di->offset; + if (!dir_emit(ctx, dentry->d_name.name, + dentry->d_name.len, ceph_present_inode(d_inode(dentry)), + d_inode(dentry)->i_mode >> 12)) { + dput(dentry); + err = 0; + break; + } + ctx->pos++; + + if (last) + dput(last); + last = dentry; + } else { + dput(dentry); + } + } +out: + ceph_readdir_cache_release(&cache_ctl); + if (last) { + int ret; + di = ceph_dentry(last); + ret = note_last_dentry(dfi, last->d_name.name, last->d_name.len, + fpos_off(di->offset) + 1); + if (ret < 0) + err = ret; + dput(last); + /* last_name no longer match cache index */ + if (dfi->readdir_cache_idx >= 0) { + dfi->readdir_cache_idx = -1; + dfi->dir_release_count = 0; + } + } + return err; +} + +static bool need_send_readdir(struct ceph_dir_file_info *dfi, loff_t pos) +{ + if (!dfi->last_readdir) + return true; + if (is_hash_order(pos)) + return !ceph_frag_contains_value(dfi->frag, fpos_hash(pos)); + else + return dfi->frag != fpos_frag(pos); +} + +static int ceph_readdir(struct file *file, struct dir_context *ctx) +{ + struct ceph_dir_file_info *dfi = file->private_data; + struct inode *inode = file_inode(file); + struct ceph_inode_info *ci = ceph_inode(inode); + struct ceph_fs_client *fsc = ceph_inode_to_client(inode); + struct ceph_mds_client *mdsc = fsc->mdsc; + int i; + int err; + unsigned frag = -1; + struct ceph_mds_reply_info_parsed *rinfo; + + dout("readdir %p file %p pos %llx\n", inode, file, ctx->pos); + if (dfi->file_info.flags & CEPH_F_ATEND) + return 0; + + /* always start with . and .. */ + if (ctx->pos == 0) { + dout("readdir off 0 -> '.'\n"); + if (!dir_emit(ctx, ".", 1, ceph_present_inode(inode), + inode->i_mode >> 12)) + return 0; + ctx->pos = 1; + } + if (ctx->pos == 1) { + u64 ino; + struct dentry *dentry = file->f_path.dentry; + + spin_lock(&dentry->d_lock); + ino = ceph_present_inode(dentry->d_parent->d_inode); + spin_unlock(&dentry->d_lock); + + dout("readdir off 1 -> '..'\n"); + if (!dir_emit(ctx, "..", 2, ino, inode->i_mode >> 12)) + return 0; + ctx->pos = 2; + } + + err = ceph_fscrypt_prepare_readdir(inode); + if (err < 0) + return err; + + spin_lock(&ci->i_ceph_lock); + /* request Fx cap. if have Fx, we don't need to release Fs cap + * for later create/unlink. */ + __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_WR); + /* can we use the dcache? */ + if (ceph_test_mount_opt(fsc, DCACHE) && + !ceph_test_mount_opt(fsc, NOASYNCREADDIR) && + ceph_snap(inode) != CEPH_SNAPDIR && + __ceph_dir_is_complete_ordered(ci) && + __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) { + int shared_gen = atomic_read(&ci->i_shared_gen); + + spin_unlock(&ci->i_ceph_lock); + err = __dcache_readdir(file, ctx, shared_gen); + if (err != -EAGAIN) + return err; + } else { + spin_unlock(&ci->i_ceph_lock); + } + + /* proceed with a normal readdir */ +more: + /* do we have the correct frag content buffered? */ + if (need_send_readdir(dfi, ctx->pos)) { + struct ceph_mds_request *req; + int op = ceph_snap(inode) == CEPH_SNAPDIR ? + CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR; + + /* discard old result, if any */ + if (dfi->last_readdir) { + ceph_mdsc_put_request(dfi->last_readdir); + dfi->last_readdir = NULL; + } + + if (is_hash_order(ctx->pos)) { + /* fragtree isn't always accurate. choose frag + * based on previous reply when possible. */ + if (frag == (unsigned)-1) + frag = ceph_choose_frag(ci, fpos_hash(ctx->pos), + NULL, NULL); + } else { + frag = fpos_frag(ctx->pos); + } + + dout("readdir fetching %llx.%llx frag %x offset '%s'\n", + ceph_vinop(inode), frag, dfi->last_name); + req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); + if (IS_ERR(req)) + return PTR_ERR(req); + + err = ceph_alloc_readdir_reply_buffer(req, inode); + if (err) { + ceph_mdsc_put_request(req); + return err; + } + /* hints to request -> mds selection code */ + req->r_direct_mode = USE_AUTH_MDS; + if (op == CEPH_MDS_OP_READDIR) { + req->r_direct_hash = ceph_frag_value(frag); + __set_bit(CEPH_MDS_R_DIRECT_IS_HASH, &req->r_req_flags); + req->r_inode_drop = CEPH_CAP_FILE_EXCL; + } + if (dfi->last_name) { + struct qstr d_name = { .name = dfi->last_name, + .len = strlen(dfi->last_name) }; + + req->r_path2 = kzalloc(NAME_MAX + 1, GFP_KERNEL); + if (!req->r_path2) { + ceph_mdsc_put_request(req); + return -ENOMEM; + } + + err = ceph_encode_encrypted_dname(inode, &d_name, + req->r_path2); + if (err < 0) { + ceph_mdsc_put_request(req); + return err; + } + } else if (is_hash_order(ctx->pos)) { + req->r_args.readdir.offset_hash = + cpu_to_le32(fpos_hash(ctx->pos)); + } + + req->r_dir_release_cnt = dfi->dir_release_count; + req->r_dir_ordered_cnt = dfi->dir_ordered_count; + req->r_readdir_cache_idx = dfi->readdir_cache_idx; + req->r_readdir_offset = dfi->next_offset; + req->r_args.readdir.frag = cpu_to_le32(frag); + req->r_args.readdir.flags = + cpu_to_le16(CEPH_READDIR_REPLY_BITFLAGS); + + req->r_inode = inode; + ihold(inode); + req->r_dentry = dget(file->f_path.dentry); + err = ceph_mdsc_do_request(mdsc, NULL, req); + if (err < 0) { + ceph_mdsc_put_request(req); + return err; + } + dout("readdir got and parsed readdir result=%d on " + "frag %x, end=%d, complete=%d, hash_order=%d\n", + err, frag, + (int)req->r_reply_info.dir_end, + (int)req->r_reply_info.dir_complete, + (int)req->r_reply_info.hash_order); + + rinfo = &req->r_reply_info; + if (le32_to_cpu(rinfo->dir_dir->frag) != frag) { + frag = le32_to_cpu(rinfo->dir_dir->frag); + if (!rinfo->hash_order) { + dfi->next_offset = req->r_readdir_offset; + /* adjust ctx->pos to beginning of frag */ + ctx->pos = ceph_make_fpos(frag, + dfi->next_offset, + false); + } + } + + dfi->frag = frag; + dfi->last_readdir = req; + + if (test_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags)) { + dfi->readdir_cache_idx = req->r_readdir_cache_idx; + if (dfi->readdir_cache_idx < 0) { + /* preclude from marking dir ordered */ + dfi->dir_ordered_count = 0; + } else if (ceph_frag_is_leftmost(frag) && + dfi->next_offset == 2) { + /* note dir version at start of readdir so + * we can tell if any dentries get dropped */ + dfi->dir_release_count = req->r_dir_release_cnt; + dfi->dir_ordered_count = req->r_dir_ordered_cnt; + } + } else { + dout("readdir !did_prepopulate\n"); + /* disable readdir cache */ + dfi->readdir_cache_idx = -1; + /* preclude from marking dir complete */ + dfi->dir_release_count = 0; + } + + /* note next offset and last dentry name */ + if (rinfo->dir_nr > 0) { + struct ceph_mds_reply_dir_entry *rde = + rinfo->dir_entries + (rinfo->dir_nr-1); + unsigned next_offset = req->r_reply_info.dir_end ? + 2 : (fpos_off(rde->offset) + 1); + err = note_last_dentry(dfi, rde->name, rde->name_len, + next_offset); + if (err) { + ceph_mdsc_put_request(dfi->last_readdir); + dfi->last_readdir = NULL; + return err; + } + } else if (req->r_reply_info.dir_end) { + dfi->next_offset = 2; + /* keep last name */ + } + } + + rinfo = &dfi->last_readdir->r_reply_info; + dout("readdir frag %x num %d pos %llx chunk first %llx\n", + dfi->frag, rinfo->dir_nr, ctx->pos, + rinfo->dir_nr ? rinfo->dir_entries[0].offset : 0LL); + + i = 0; + /* search start position */ + if (rinfo->dir_nr > 0) { + int step, nr = rinfo->dir_nr; + while (nr > 0) { + step = nr >> 1; + if (rinfo->dir_entries[i + step].offset < ctx->pos) { + i += step + 1; + nr -= step + 1; + } else { + nr = step; + } + } + } + for (; i < rinfo->dir_nr; i++) { + struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i; + + if (rde->offset < ctx->pos) { + pr_warn("%s: rde->offset 0x%llx ctx->pos 0x%llx\n", + __func__, rde->offset, ctx->pos); + return -EIO; + } + + if (WARN_ON_ONCE(!rde->inode.in)) + return -EIO; + + ctx->pos = rde->offset; + dout("readdir (%d/%d) -> %llx '%.*s' %p\n", + i, rinfo->dir_nr, ctx->pos, + rde->name_len, rde->name, &rde->inode.in); + + if (!dir_emit(ctx, rde->name, rde->name_len, + ceph_present_ino(inode->i_sb, le64_to_cpu(rde->inode.in->ino)), + le32_to_cpu(rde->inode.in->mode) >> 12)) { + /* + * NOTE: Here no need to put the 'dfi->last_readdir', + * because when dir_emit stops us it's most likely + * doesn't have enough memory, etc. So for next readdir + * it will continue. + */ + dout("filldir stopping us...\n"); + return 0; + } + + /* Reset the lengths to their original allocated vals */ + ctx->pos++; + } + + ceph_mdsc_put_request(dfi->last_readdir); + dfi->last_readdir = NULL; + + if (dfi->next_offset > 2) { + frag = dfi->frag; + goto more; + } + + /* more frags? */ + if (!ceph_frag_is_rightmost(dfi->frag)) { + frag = ceph_frag_next(dfi->frag); + if (is_hash_order(ctx->pos)) { + loff_t new_pos = ceph_make_fpos(ceph_frag_value(frag), + dfi->next_offset, true); + if (new_pos > ctx->pos) + ctx->pos = new_pos; + /* keep last_name */ + } else { + ctx->pos = ceph_make_fpos(frag, dfi->next_offset, + false); + kfree(dfi->last_name); + dfi->last_name = NULL; + } + dout("readdir next frag is %x\n", frag); + goto more; + } + dfi->file_info.flags |= CEPH_F_ATEND; + + /* + * if dir_release_count still matches the dir, no dentries + * were released during the whole readdir, and we should have + * the complete dir contents in our cache. + */ + if (atomic64_read(&ci->i_release_count) == + dfi->dir_release_count) { + spin_lock(&ci->i_ceph_lock); + if (dfi->dir_ordered_count == + atomic64_read(&ci->i_ordered_count)) { + dout(" marking %p complete and ordered\n", inode); + /* use i_size to track number of entries in + * readdir cache */ + BUG_ON(dfi->readdir_cache_idx < 0); + i_size_write(inode, dfi->readdir_cache_idx * + sizeof(struct dentry*)); + } else { + dout(" marking %p complete\n", inode); + } + __ceph_dir_set_complete(ci, dfi->dir_release_count, + dfi->dir_ordered_count); + spin_unlock(&ci->i_ceph_lock); + } + dout("readdir %p file %p done.\n", inode, file); + return 0; +} + +static void reset_readdir(struct ceph_dir_file_info *dfi) +{ + if (dfi->last_readdir) { + ceph_mdsc_put_request(dfi->last_readdir); + dfi->last_readdir = NULL; + } + kfree(dfi->last_name); + dfi->last_name = NULL; + dfi->dir_release_count = 0; + dfi->readdir_cache_idx = -1; + dfi->next_offset = 2; /* compensate for . and .. */ + dfi->file_info.flags &= ~CEPH_F_ATEND; +} + +/* + * discard buffered readdir content on seekdir(0), or seek to new frag, + * or seek prior to current chunk + */ +static bool need_reset_readdir(struct ceph_dir_file_info *dfi, loff_t new_pos) +{ + struct ceph_mds_reply_info_parsed *rinfo; + loff_t chunk_offset; + if (new_pos == 0) + return true; + if (is_hash_order(new_pos)) { + /* no need to reset last_name for a forward seek when + * dentries are sotred in hash order */ + } else if (dfi->frag != fpos_frag(new_pos)) { + return true; + } + rinfo = dfi->last_readdir ? &dfi->last_readdir->r_reply_info : NULL; + if (!rinfo || !rinfo->dir_nr) + return true; + chunk_offset = rinfo->dir_entries[0].offset; + return new_pos < chunk_offset || + is_hash_order(new_pos) != is_hash_order(chunk_offset); +} + +static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence) +{ + struct ceph_dir_file_info *dfi = file->private_data; + struct inode *inode = file->f_mapping->host; + loff_t retval; + + inode_lock(inode); + retval = -EINVAL; + switch (whence) { + case SEEK_CUR: + offset += file->f_pos; + break; + case SEEK_SET: + break; + case SEEK_END: + retval = -EOPNOTSUPP; + goto out; + default: + goto out; + } + + if (offset >= 0) { + if (need_reset_readdir(dfi, offset)) { + dout("dir_llseek dropping %p content\n", file); + reset_readdir(dfi); + } else if (is_hash_order(offset) && offset > file->f_pos) { + /* for hash offset, we don't know if a forward seek + * is within same frag */ + dfi->dir_release_count = 0; + dfi->readdir_cache_idx = -1; + } + + if (offset != file->f_pos) { + file->f_pos = offset; + file->f_version = 0; + dfi->file_info.flags &= ~CEPH_F_ATEND; + } + retval = offset; + } +out: + inode_unlock(inode); + return retval; +} + +/* + * Handle lookups for the hidden .snap directory. + */ +struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req, + struct dentry *dentry) +{ + struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb); + struct inode *parent = d_inode(dentry->d_parent); /* we hold i_rwsem */ + + /* .snap dir? */ + if (ceph_snap(parent) == CEPH_NOSNAP && + strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) { + struct dentry *res; + struct inode *inode = ceph_get_snapdir(parent); + + res = d_splice_alias(inode, dentry); + dout("ENOENT on snapdir %p '%pd', linking to snapdir %p. Spliced dentry %p\n", + dentry, dentry, inode, res); + if (res) + dentry = res; + } + return dentry; +} + +/* + * Figure out final result of a lookup/open request. + * + * Mainly, make sure we return the final req->r_dentry (if it already + * existed) in place of the original VFS-provided dentry when they + * differ. + * + * Gracefully handle the case where the MDS replies with -ENOENT and + * no trace (which it may do, at its discretion, e.g., if it doesn't + * care to issue a lease on the negative dentry). + */ +struct dentry *ceph_finish_lookup(struct ceph_mds_request *req, + struct dentry *dentry, int err) +{ + if (err == -ENOENT) { + /* no trace? */ + err = 0; + if (!req->r_reply_info.head->is_dentry) { + dout("ENOENT and no trace, dentry %p inode %p\n", + dentry, d_inode(dentry)); + if (d_really_is_positive(dentry)) { + d_drop(dentry); + err = -ENOENT; + } else { + d_add(dentry, NULL); + } + } + } + if (err) + dentry = ERR_PTR(err); + else if (dentry != req->r_dentry) + dentry = dget(req->r_dentry); /* we got spliced */ + else + dentry = NULL; + return dentry; +} + +static bool is_root_ceph_dentry(struct inode *inode, struct dentry *dentry) +{ + return ceph_ino(inode) == CEPH_INO_ROOT && + strncmp(dentry->d_name.name, ".ceph", 5) == 0; +} + +/* + * Look up a single dir entry. If there is a lookup intent, inform + * the MDS so that it gets our 'caps wanted' value in a single op. + */ +static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry, + unsigned int flags) +{ + struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb); + struct ceph_mds_request *req; + int op; + int mask; + int err; + + dout("lookup %p dentry %p '%pd'\n", + dir, dentry, dentry); + + if (dentry->d_name.len > NAME_MAX) + return ERR_PTR(-ENAMETOOLONG); + + if (IS_ENCRYPTED(dir)) { + bool had_key = fscrypt_has_encryption_key(dir); + + err = fscrypt_prepare_lookup_partial(dir, dentry); + if (err < 0) + return ERR_PTR(err); + + /* mark directory as incomplete if it has been unlocked */ + if (!had_key && fscrypt_has_encryption_key(dir)) + ceph_dir_clear_complete(dir); + } + + /* can we conclude ENOENT locally? */ + if (d_really_is_negative(dentry)) { + struct ceph_inode_info *ci = ceph_inode(dir); + struct ceph_dentry_info *di = ceph_dentry(dentry); + + spin_lock(&ci->i_ceph_lock); + dout(" dir %p flags are 0x%lx\n", dir, ci->i_ceph_flags); + if (strncmp(dentry->d_name.name, + fsc->mount_options->snapdir_name, + dentry->d_name.len) && + !is_root_ceph_dentry(dir, dentry) && + ceph_test_mount_opt(fsc, DCACHE) && + __ceph_dir_is_complete(ci) && + __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) { + __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD); + spin_unlock(&ci->i_ceph_lock); + dout(" dir %p complete, -ENOENT\n", dir); + d_add(dentry, NULL); + di->lease_shared_gen = atomic_read(&ci->i_shared_gen); + return NULL; + } + spin_unlock(&ci->i_ceph_lock); + } + + op = ceph_snap(dir) == CEPH_SNAPDIR ? + CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP; + req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS); + if (IS_ERR(req)) + return ERR_CAST(req); + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + + mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED; + if (ceph_security_xattr_wanted(dir)) + mask |= CEPH_CAP_XATTR_SHARED; + req->r_args.getattr.mask = cpu_to_le32(mask); + + ihold(dir); + req->r_parent = dir; + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + err = ceph_mdsc_do_request(mdsc, NULL, req); + if (err == -ENOENT) { + struct dentry *res; + + res = ceph_handle_snapdir(req, dentry); + if (IS_ERR(res)) { + err = PTR_ERR(res); + } else { + dentry = res; + err = 0; + } + } + dentry = ceph_finish_lookup(req, dentry, err); + ceph_mdsc_put_request(req); /* will dput(dentry) */ + dout("lookup result=%p\n", dentry); + return dentry; +} + +/* + * If we do a create but get no trace back from the MDS, follow up with + * a lookup (the VFS expects us to link up the provided dentry). + */ +int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry) +{ + struct dentry *result = ceph_lookup(dir, dentry, 0); + + if (result && !IS_ERR(result)) { + /* + * We created the item, then did a lookup, and found + * it was already linked to another inode we already + * had in our cache (and thus got spliced). To not + * confuse VFS (especially when inode is a directory), + * we don't link our dentry to that inode, return an + * error instead. + * + * This event should be rare and it happens only when + * we talk to old MDS. Recent MDS does not send traceless + * reply for request that creates new inode. + */ + d_drop(result); + return -ESTALE; + } + return PTR_ERR(result); +} + +static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode, dev_t rdev) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb); + struct ceph_mds_request *req; + struct ceph_acl_sec_ctx as_ctx = {}; + int err; + + if (ceph_snap(dir) != CEPH_NOSNAP) + return -EROFS; + + err = ceph_wait_on_conflict_unlink(dentry); + if (err) + return err; + + if (ceph_quota_is_max_files_exceeded(dir)) { + err = -EDQUOT; + goto out; + } + + dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n", + dir, dentry, mode, rdev); + req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto out; + } + + req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx); + if (IS_ERR(req->r_new_inode)) { + err = PTR_ERR(req->r_new_inode); + req->r_new_inode = NULL; + goto out_req; + } + + if (S_ISREG(mode) && IS_ENCRYPTED(dir)) + set_bit(CEPH_MDS_R_FSCRYPT_FILE, &req->r_req_flags); + + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_parent = dir; + ihold(dir); + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + req->r_args.mknod.mode = cpu_to_le32(mode); + req->r_args.mknod.rdev = cpu_to_le32(rdev); + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL | + CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + + ceph_as_ctx_to_req(req, &as_ctx); + + err = ceph_mdsc_do_request(mdsc, dir, req); + if (!err && !req->r_reply_info.head->is_dentry) + err = ceph_handle_notrace_create(dir, dentry); +out_req: + ceph_mdsc_put_request(req); +out: + if (!err) + ceph_init_inode_acls(d_inode(dentry), &as_ctx); + else + d_drop(dentry); + ceph_release_acl_sec_ctx(&as_ctx); + return err; +} + +static int ceph_create(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode, bool excl) +{ + return ceph_mknod(idmap, dir, dentry, mode, 0); +} + +#if IS_ENABLED(CONFIG_FS_ENCRYPTION) +static int prep_encrypted_symlink_target(struct ceph_mds_request *req, + const char *dest) +{ + int err; + int len = strlen(dest); + struct fscrypt_str osd_link = FSTR_INIT(NULL, 0); + + err = fscrypt_prepare_symlink(req->r_parent, dest, len, PATH_MAX, + &osd_link); + if (err) + goto out; + + err = fscrypt_encrypt_symlink(req->r_new_inode, dest, len, &osd_link); + if (err) + goto out; + + req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL); + if (!req->r_path2) { + err = -ENOMEM; + goto out; + } + + len = ceph_base64_encode(osd_link.name, osd_link.len, req->r_path2); + req->r_path2[len] = '\0'; +out: + fscrypt_fname_free_buffer(&osd_link); + return err; +} +#else +static int prep_encrypted_symlink_target(struct ceph_mds_request *req, + const char *dest) +{ + return -EOPNOTSUPP; +} +#endif + +static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, const char *dest) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb); + struct ceph_mds_request *req; + struct ceph_acl_sec_ctx as_ctx = {}; + umode_t mode = S_IFLNK | 0777; + int err; + + if (ceph_snap(dir) != CEPH_NOSNAP) + return -EROFS; + + err = ceph_wait_on_conflict_unlink(dentry); + if (err) + return err; + + if (ceph_quota_is_max_files_exceeded(dir)) { + err = -EDQUOT; + goto out; + } + + dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest); + req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto out; + } + + req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx); + if (IS_ERR(req->r_new_inode)) { + err = PTR_ERR(req->r_new_inode); + req->r_new_inode = NULL; + goto out_req; + } + + req->r_parent = dir; + ihold(dir); + + if (IS_ENCRYPTED(req->r_new_inode)) { + err = prep_encrypted_symlink_target(req, dest); + if (err) + goto out_req; + } else { + req->r_path2 = kstrdup(dest, GFP_KERNEL); + if (!req->r_path2) { + err = -ENOMEM; + goto out_req; + } + } + + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL | + CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + + ceph_as_ctx_to_req(req, &as_ctx); + + err = ceph_mdsc_do_request(mdsc, dir, req); + if (!err && !req->r_reply_info.head->is_dentry) + err = ceph_handle_notrace_create(dir, dentry); +out_req: + ceph_mdsc_put_request(req); +out: + if (err) + d_drop(dentry); + ceph_release_acl_sec_ctx(&as_ctx); + return err; +} + +static int ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir, + struct dentry *dentry, umode_t mode) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb); + struct ceph_mds_request *req; + struct ceph_acl_sec_ctx as_ctx = {}; + int err; + int op; + + err = ceph_wait_on_conflict_unlink(dentry); + if (err) + return err; + + if (ceph_snap(dir) == CEPH_SNAPDIR) { + /* mkdir .snap/foo is a MKSNAP */ + op = CEPH_MDS_OP_MKSNAP; + dout("mksnap dir %p snap '%pd' dn %p\n", dir, + dentry, dentry); + } else if (ceph_snap(dir) == CEPH_NOSNAP) { + dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode); + op = CEPH_MDS_OP_MKDIR; + } else { + err = -EROFS; + goto out; + } + + if (op == CEPH_MDS_OP_MKDIR && + ceph_quota_is_max_files_exceeded(dir)) { + err = -EDQUOT; + goto out; + } + if ((op == CEPH_MDS_OP_MKSNAP) && IS_ENCRYPTED(dir) && + !fscrypt_has_encryption_key(dir)) { + err = -ENOKEY; + goto out; + } + + + req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto out; + } + + mode |= S_IFDIR; + req->r_new_inode = ceph_new_inode(dir, dentry, &mode, &as_ctx); + if (IS_ERR(req->r_new_inode)) { + err = PTR_ERR(req->r_new_inode); + req->r_new_inode = NULL; + goto out_req; + } + + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_parent = dir; + ihold(dir); + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + req->r_args.mkdir.mode = cpu_to_le32(mode); + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_AUTH_EXCL | + CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + + ceph_as_ctx_to_req(req, &as_ctx); + + err = ceph_mdsc_do_request(mdsc, dir, req); + if (!err && + !req->r_reply_info.head->is_target && + !req->r_reply_info.head->is_dentry) + err = ceph_handle_notrace_create(dir, dentry); +out_req: + ceph_mdsc_put_request(req); +out: + if (!err) + ceph_init_inode_acls(d_inode(dentry), &as_ctx); + else + d_drop(dentry); + ceph_release_acl_sec_ctx(&as_ctx); + return err; +} + +static int ceph_link(struct dentry *old_dentry, struct inode *dir, + struct dentry *dentry) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb); + struct ceph_mds_request *req; + int err; + + if (dentry->d_flags & DCACHE_DISCONNECTED) + return -EINVAL; + + err = ceph_wait_on_conflict_unlink(dentry); + if (err) + return err; + + if (ceph_snap(dir) != CEPH_NOSNAP) + return -EROFS; + + err = fscrypt_prepare_link(old_dentry, dir, dentry); + if (err) + return err; + + dout("link in dir %p %llx.%llx old_dentry %p:'%pd' dentry %p:'%pd'\n", + dir, ceph_vinop(dir), old_dentry, old_dentry, dentry, dentry); + req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS); + if (IS_ERR(req)) { + d_drop(dentry); + return PTR_ERR(req); + } + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_old_dentry = dget(old_dentry); + /* + * The old_dentry maybe a DCACHE_DISCONNECTED dentry, then we + * will just pass the ino# to MDSs. + */ + if (old_dentry->d_flags & DCACHE_DISCONNECTED) + req->r_ino2 = ceph_vino(d_inode(old_dentry)); + req->r_parent = dir; + ihold(dir); + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + /* release LINK_SHARED on source inode (mds will lock it) */ + req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL; + err = ceph_mdsc_do_request(mdsc, dir, req); + if (err) { + d_drop(dentry); + } else if (!req->r_reply_info.head->is_dentry) { + ihold(d_inode(old_dentry)); + d_instantiate(dentry, d_inode(old_dentry)); + } + ceph_mdsc_put_request(req); + return err; +} + +static void ceph_async_unlink_cb(struct ceph_mds_client *mdsc, + struct ceph_mds_request *req) +{ + struct dentry *dentry = req->r_dentry; + struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb); + struct ceph_dentry_info *di = ceph_dentry(dentry); + int result = req->r_err ? req->r_err : + le32_to_cpu(req->r_reply_info.head->result); + + if (!test_bit(CEPH_DENTRY_ASYNC_UNLINK_BIT, &di->flags)) + pr_warn("%s dentry %p:%pd async unlink bit is not set\n", + __func__, dentry, dentry); + + spin_lock(&fsc->async_unlink_conflict_lock); + hash_del_rcu(&di->hnode); + spin_unlock(&fsc->async_unlink_conflict_lock); + + spin_lock(&dentry->d_lock); + di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK; + wake_up_bit(&di->flags, CEPH_DENTRY_ASYNC_UNLINK_BIT); + spin_unlock(&dentry->d_lock); + + synchronize_rcu(); + + if (result == -EJUKEBOX) + goto out; + + /* If op failed, mark everyone involved for errors */ + if (result) { + int pathlen = 0; + u64 base = 0; + char *path = ceph_mdsc_build_path(dentry, &pathlen, + &base, 0); + + /* mark error on parent + clear complete */ + mapping_set_error(req->r_parent->i_mapping, result); + ceph_dir_clear_complete(req->r_parent); + + /* drop the dentry -- we don't know its status */ + if (!d_unhashed(dentry)) + d_drop(dentry); + + /* mark inode itself for an error (since metadata is bogus) */ + mapping_set_error(req->r_old_inode->i_mapping, result); + + pr_warn("async unlink failure path=(%llx)%s result=%d!\n", + base, IS_ERR(path) ? "<<bad>>" : path, result); + ceph_mdsc_free_path(path, pathlen); + } +out: + iput(req->r_old_inode); + ceph_mdsc_release_dir_caps(req); +} + +static int get_caps_for_async_unlink(struct inode *dir, struct dentry *dentry) +{ + struct ceph_inode_info *ci = ceph_inode(dir); + struct ceph_dentry_info *di; + int got = 0, want = CEPH_CAP_FILE_EXCL | CEPH_CAP_DIR_UNLINK; + + spin_lock(&ci->i_ceph_lock); + if ((__ceph_caps_issued(ci, NULL) & want) == want) { + ceph_take_cap_refs(ci, want, false); + got = want; + } + spin_unlock(&ci->i_ceph_lock); + + /* If we didn't get anything, return 0 */ + if (!got) + return 0; + + spin_lock(&dentry->d_lock); + di = ceph_dentry(dentry); + /* + * - We are holding Fx, which implies Fs caps. + * - Only support async unlink for primary linkage + */ + if (atomic_read(&ci->i_shared_gen) != di->lease_shared_gen || + !(di->flags & CEPH_DENTRY_PRIMARY_LINK)) + want = 0; + spin_unlock(&dentry->d_lock); + + /* Do we still want what we've got? */ + if (want == got) + return got; + + ceph_put_cap_refs(ci, got); + return 0; +} + +/* + * rmdir and unlink are differ only by the metadata op code + */ +static int ceph_unlink(struct inode *dir, struct dentry *dentry) +{ + struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); + struct ceph_mds_client *mdsc = fsc->mdsc; + struct inode *inode = d_inode(dentry); + struct ceph_mds_request *req; + bool try_async = ceph_test_mount_opt(fsc, ASYNC_DIROPS); + int err = -EROFS; + int op; + + if (ceph_snap(dir) == CEPH_SNAPDIR) { + /* rmdir .snap/foo is RMSNAP */ + dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry); + op = CEPH_MDS_OP_RMSNAP; + } else if (ceph_snap(dir) == CEPH_NOSNAP) { + dout("unlink/rmdir dir %p dn %p inode %p\n", + dir, dentry, inode); + op = d_is_dir(dentry) ? + CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK; + } else + goto out; +retry: + req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); + if (IS_ERR(req)) { + err = PTR_ERR(req); + goto out; + } + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_parent = dir; + ihold(dir); + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + req->r_inode_drop = ceph_drop_caps_for_unlink(inode); + + if (try_async && op == CEPH_MDS_OP_UNLINK && + (req->r_dir_caps = get_caps_for_async_unlink(dir, dentry))) { + struct ceph_dentry_info *di = ceph_dentry(dentry); + + dout("async unlink on %llu/%.*s caps=%s", ceph_ino(dir), + dentry->d_name.len, dentry->d_name.name, + ceph_cap_string(req->r_dir_caps)); + set_bit(CEPH_MDS_R_ASYNC, &req->r_req_flags); + req->r_callback = ceph_async_unlink_cb; + req->r_old_inode = d_inode(dentry); + ihold(req->r_old_inode); + + spin_lock(&dentry->d_lock); + di->flags |= CEPH_DENTRY_ASYNC_UNLINK; + spin_unlock(&dentry->d_lock); + + spin_lock(&fsc->async_unlink_conflict_lock); + hash_add_rcu(fsc->async_unlink_conflict, &di->hnode, + dentry->d_name.hash); + spin_unlock(&fsc->async_unlink_conflict_lock); + + err = ceph_mdsc_submit_request(mdsc, dir, req); + if (!err) { + /* + * We have enough caps, so we assume that the unlink + * will succeed. Fix up the target inode and dcache. + */ + drop_nlink(inode); + d_delete(dentry); + } else { + spin_lock(&fsc->async_unlink_conflict_lock); + hash_del_rcu(&di->hnode); + spin_unlock(&fsc->async_unlink_conflict_lock); + + spin_lock(&dentry->d_lock); + di->flags &= ~CEPH_DENTRY_ASYNC_UNLINK; + spin_unlock(&dentry->d_lock); + + if (err == -EJUKEBOX) { + try_async = false; + ceph_mdsc_put_request(req); + goto retry; + } + } + } else { + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + err = ceph_mdsc_do_request(mdsc, dir, req); + if (!err && !req->r_reply_info.head->is_dentry) + d_delete(dentry); + } + + ceph_mdsc_put_request(req); +out: + return err; +} + +static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir, + struct dentry *old_dentry, struct inode *new_dir, + struct dentry *new_dentry, unsigned int flags) +{ + struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(old_dir->i_sb); + struct ceph_mds_request *req; + int op = CEPH_MDS_OP_RENAME; + int err; + + if (flags) + return -EINVAL; + + if (ceph_snap(old_dir) != ceph_snap(new_dir)) + return -EXDEV; + if (ceph_snap(old_dir) != CEPH_NOSNAP) { + if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR) + op = CEPH_MDS_OP_RENAMESNAP; + else + return -EROFS; + } + /* don't allow cross-quota renames */ + if ((old_dir != new_dir) && + (!ceph_quota_is_same_realm(old_dir, new_dir))) + return -EXDEV; + + err = ceph_wait_on_conflict_unlink(new_dentry); + if (err) + return err; + + err = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry, + flags); + if (err) + return err; + + dout("rename dir %p dentry %p to dir %p dentry %p\n", + old_dir, old_dentry, new_dir, new_dentry); + req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS); + if (IS_ERR(req)) + return PTR_ERR(req); + ihold(old_dir); + req->r_dentry = dget(new_dentry); + req->r_num_caps = 2; + req->r_old_dentry = dget(old_dentry); + req->r_old_dentry_dir = old_dir; + req->r_parent = new_dir; + ihold(new_dir); + set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); + req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL; + req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL; + req->r_dentry_drop = CEPH_CAP_FILE_SHARED | CEPH_CAP_XATTR_EXCL; + req->r_dentry_unless = CEPH_CAP_FILE_EXCL; + /* release LINK_RDCACHE on source inode (mds will lock it) */ + req->r_old_inode_drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL; + if (d_really_is_positive(new_dentry)) { + req->r_inode_drop = + ceph_drop_caps_for_unlink(d_inode(new_dentry)); + } + err = ceph_mdsc_do_request(mdsc, old_dir, req); + if (!err && !req->r_reply_info.head->is_dentry) { + /* + * Normally d_move() is done by fill_trace (called by + * do_request, above). If there is no trace, we need + * to do it here. + */ + d_move(old_dentry, new_dentry); + } + ceph_mdsc_put_request(req); + return err; +} + +/* + * Move dentry to tail of mdsc->dentry_leases list when lease is updated. + * Leases at front of the list will expire first. (Assume all leases have + * similar duration) + * + * Called under dentry->d_lock. + */ +void __ceph_dentry_lease_touch(struct ceph_dentry_info *di) +{ + struct dentry *dn = di->dentry; + struct ceph_mds_client *mdsc; + + dout("dentry_lease_touch %p %p '%pd'\n", di, dn, dn); + + di->flags |= CEPH_DENTRY_LEASE_LIST; + if (di->flags & CEPH_DENTRY_SHRINK_LIST) { + di->flags |= CEPH_DENTRY_REFERENCED; + return; + } + + mdsc = ceph_sb_to_client(dn->d_sb)->mdsc; + spin_lock(&mdsc->dentry_list_lock); + list_move_tail(&di->lease_list, &mdsc->dentry_leases); + spin_unlock(&mdsc->dentry_list_lock); +} + +static void __dentry_dir_lease_touch(struct ceph_mds_client* mdsc, + struct ceph_dentry_info *di) +{ + di->flags &= ~(CEPH_DENTRY_LEASE_LIST | CEPH_DENTRY_REFERENCED); + di->lease_gen = 0; + di->time = jiffies; + list_move_tail(&di->lease_list, &mdsc->dentry_dir_leases); +} + +/* + * When dir lease is used, add dentry to tail of mdsc->dentry_dir_leases + * list if it's not in the list, otherwise set 'referenced' flag. + * + * Called under dentry->d_lock. + */ +void __ceph_dentry_dir_lease_touch(struct ceph_dentry_info *di) +{ + struct dentry *dn = di->dentry; + struct ceph_mds_client *mdsc; + + dout("dentry_dir_lease_touch %p %p '%pd' (offset 0x%llx)\n", + di, dn, dn, di->offset); + + if (!list_empty(&di->lease_list)) { + if (di->flags & CEPH_DENTRY_LEASE_LIST) { + /* don't remove dentry from dentry lease list + * if its lease is valid */ + if (__dentry_lease_is_valid(di)) + return; + } else { + di->flags |= CEPH_DENTRY_REFERENCED; + return; + } + } + + if (di->flags & CEPH_DENTRY_SHRINK_LIST) { + di->flags |= CEPH_DENTRY_REFERENCED; + di->flags &= ~CEPH_DENTRY_LEASE_LIST; + return; + } + + mdsc = ceph_sb_to_client(dn->d_sb)->mdsc; + spin_lock(&mdsc->dentry_list_lock); + __dentry_dir_lease_touch(mdsc, di), + spin_unlock(&mdsc->dentry_list_lock); +} + +static void __dentry_lease_unlist(struct ceph_dentry_info *di) +{ + struct ceph_mds_client *mdsc; + if (di->flags & CEPH_DENTRY_SHRINK_LIST) + return; + if (list_empty(&di->lease_list)) + return; + + mdsc = ceph_sb_to_client(di->dentry->d_sb)->mdsc; + spin_lock(&mdsc->dentry_list_lock); + list_del_init(&di->lease_list); + spin_unlock(&mdsc->dentry_list_lock); +} + +enum { + KEEP = 0, + DELETE = 1, + TOUCH = 2, + STOP = 4, +}; + +struct ceph_lease_walk_control { + bool dir_lease; + bool expire_dir_lease; + unsigned long nr_to_scan; + unsigned long dir_lease_ttl; +}; + +static unsigned long +__dentry_leases_walk(struct ceph_mds_client *mdsc, + struct ceph_lease_walk_control *lwc, + int (*check)(struct dentry*, void*)) +{ + struct ceph_dentry_info *di, *tmp; + struct dentry *dentry, *last = NULL; + struct list_head* list; + LIST_HEAD(dispose); + unsigned long freed = 0; + int ret = 0; + + list = lwc->dir_lease ? &mdsc->dentry_dir_leases : &mdsc->dentry_leases; + spin_lock(&mdsc->dentry_list_lock); + list_for_each_entry_safe(di, tmp, list, lease_list) { + if (!lwc->nr_to_scan) + break; + --lwc->nr_to_scan; + + dentry = di->dentry; + if (last == dentry) + break; + + if (!spin_trylock(&dentry->d_lock)) + continue; + + if (__lockref_is_dead(&dentry->d_lockref)) { + list_del_init(&di->lease_list); + goto next; + } + + ret = check(dentry, lwc); + if (ret & TOUCH) { + /* move it into tail of dir lease list */ + __dentry_dir_lease_touch(mdsc, di); + if (!last) + last = dentry; + } + if (ret & DELETE) { + /* stale lease */ + di->flags &= ~CEPH_DENTRY_REFERENCED; + if (dentry->d_lockref.count > 0) { + /* update_dentry_lease() will re-add + * it to lease list, or + * ceph_d_delete() will return 1 when + * last reference is dropped */ + list_del_init(&di->lease_list); + } else { + di->flags |= CEPH_DENTRY_SHRINK_LIST; + list_move_tail(&di->lease_list, &dispose); + dget_dlock(dentry); + } + } +next: + spin_unlock(&dentry->d_lock); + if (ret & STOP) + break; + } + spin_unlock(&mdsc->dentry_list_lock); + + while (!list_empty(&dispose)) { + di = list_first_entry(&dispose, struct ceph_dentry_info, + lease_list); + dentry = di->dentry; + spin_lock(&dentry->d_lock); + + list_del_init(&di->lease_list); + di->flags &= ~CEPH_DENTRY_SHRINK_LIST; + if (di->flags & CEPH_DENTRY_REFERENCED) { + spin_lock(&mdsc->dentry_list_lock); + if (di->flags & CEPH_DENTRY_LEASE_LIST) { + list_add_tail(&di->lease_list, + &mdsc->dentry_leases); + } else { + __dentry_dir_lease_touch(mdsc, di); + } + spin_unlock(&mdsc->dentry_list_lock); + } else { + freed++; + } + + spin_unlock(&dentry->d_lock); + /* ceph_d_delete() does the trick */ + dput(dentry); + } + return freed; +} + +static int __dentry_lease_check(struct dentry *dentry, void *arg) +{ + struct ceph_dentry_info *di = ceph_dentry(dentry); + int ret; + + if (__dentry_lease_is_valid(di)) + return STOP; + ret = __dir_lease_try_check(dentry); + if (ret == -EBUSY) + return KEEP; + if (ret > 0) + return TOUCH; + return DELETE; +} + +static int __dir_lease_check(struct dentry *dentry, void *arg) +{ + struct ceph_lease_walk_control *lwc = arg; + struct ceph_dentry_info *di = ceph_dentry(dentry); + + int ret = __dir_lease_try_check(dentry); + if (ret == -EBUSY) + return KEEP; + if (ret > 0) { + if (time_before(jiffies, di->time + lwc->dir_lease_ttl)) + return STOP; + /* Move dentry to tail of dir lease list if we don't want + * to delete it. So dentries in the list are checked in a + * round robin manner */ + if (!lwc->expire_dir_lease) + return TOUCH; + if (dentry->d_lockref.count > 0 || + (di->flags & CEPH_DENTRY_REFERENCED)) + return TOUCH; + /* invalidate dir lease */ + di->lease_shared_gen = 0; + } + return DELETE; +} + +int ceph_trim_dentries(struct ceph_mds_client *mdsc) +{ + struct ceph_lease_walk_control lwc; + unsigned long count; + unsigned long freed; + + spin_lock(&mdsc->caps_list_lock); + if (mdsc->caps_use_max > 0 && + mdsc->caps_use_count > mdsc->caps_use_max) + count = mdsc->caps_use_count - mdsc->caps_use_max; + else + count = 0; + spin_unlock(&mdsc->caps_list_lock); + + lwc.dir_lease = false; + lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE * 2; + freed = __dentry_leases_walk(mdsc, &lwc, __dentry_lease_check); + if (!lwc.nr_to_scan) /* more invalid leases */ + return -EAGAIN; + + if (lwc.nr_to_scan < CEPH_CAPS_PER_RELEASE) + lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE; + + lwc.dir_lease = true; + lwc.expire_dir_lease = freed < count; + lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ; + freed +=__dentry_leases_walk(mdsc, &lwc, __dir_lease_check); + if (!lwc.nr_to_scan) /* more to check */ + return -EAGAIN; + + return freed > 0 ? 1 : 0; +} + +/* + * Ensure a dentry lease will no longer revalidate. + */ +void ceph_invalidate_dentry_lease(struct dentry *dentry) +{ + struct ceph_dentry_info *di = ceph_dentry(dentry); + spin_lock(&dentry->d_lock); + di->time = jiffies; + di->lease_shared_gen = 0; + di->flags &= ~CEPH_DENTRY_PRIMARY_LINK; + __dentry_lease_unlist(di); + spin_unlock(&dentry->d_lock); +} + +/* + * Check if dentry lease is valid. If not, delete the lease. Try to + * renew if the least is more than half up. + */ +static bool __dentry_lease_is_valid(struct ceph_dentry_info *di) +{ + struct ceph_mds_session *session; + + if (!di->lease_gen) + return false; + + session = di->lease_session; + if (session) { + u32 gen; + unsigned long ttl; + + gen = atomic_read(&session->s_cap_gen); + ttl = session->s_cap_ttl; + + if (di->lease_gen == gen && + time_before(jiffies, ttl) && + time_before(jiffies, di->time)) + return true; + } + di->lease_gen = 0; + return false; +} + +static int dentry_lease_is_valid(struct dentry *dentry, unsigned int flags) +{ + struct ceph_dentry_info *di; + struct ceph_mds_session *session = NULL; + u32 seq = 0; + int valid = 0; + + spin_lock(&dentry->d_lock); + di = ceph_dentry(dentry); + if (di && __dentry_lease_is_valid(di)) { + valid = 1; + + if (di->lease_renew_after && + time_after(jiffies, di->lease_renew_after)) { + /* + * We should renew. If we're in RCU walk mode + * though, we can't do that so just return + * -ECHILD. + */ + if (flags & LOOKUP_RCU) { + valid = -ECHILD; + } else { + session = ceph_get_mds_session(di->lease_session); + seq = di->lease_seq; + di->lease_renew_after = 0; + di->lease_renew_from = jiffies; + } + } + } + spin_unlock(&dentry->d_lock); + + if (session) { + ceph_mdsc_lease_send_msg(session, dentry, + CEPH_MDS_LEASE_RENEW, seq); + ceph_put_mds_session(session); + } + dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid); + return valid; +} + +/* + * Called under dentry->d_lock. + */ +static int __dir_lease_try_check(const struct dentry *dentry) +{ + struct ceph_dentry_info *di = ceph_dentry(dentry); + struct inode *dir; + struct ceph_inode_info *ci; + int valid = 0; + + if (!di->lease_shared_gen) + return 0; + if (IS_ROOT(dentry)) + return 0; + + dir = d_inode(dentry->d_parent); + ci = ceph_inode(dir); + + if (spin_trylock(&ci->i_ceph_lock)) { + if (atomic_read(&ci->i_shared_gen) == di->lease_shared_gen && + __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 0)) + valid = 1; + spin_unlock(&ci->i_ceph_lock); + } else { + valid = -EBUSY; + } + + if (!valid) + di->lease_shared_gen = 0; + return valid; +} + +/* + * Check if directory-wide content lease/cap is valid. + */ +static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry, + struct ceph_mds_client *mdsc) +{ + struct ceph_inode_info *ci = ceph_inode(dir); + int valid; + int shared_gen; + + spin_lock(&ci->i_ceph_lock); + valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1); + if (valid) { + __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD); + shared_gen = atomic_read(&ci->i_shared_gen); + } + spin_unlock(&ci->i_ceph_lock); + if (valid) { + struct ceph_dentry_info *di; + spin_lock(&dentry->d_lock); + di = ceph_dentry(dentry); + if (dir == d_inode(dentry->d_parent) && + di && di->lease_shared_gen == shared_gen) + __ceph_dentry_dir_lease_touch(di); + else + valid = 0; + spin_unlock(&dentry->d_lock); + } + dout("dir_lease_is_valid dir %p v%u dentry %p = %d\n", + dir, (unsigned)atomic_read(&ci->i_shared_gen), dentry, valid); + return valid; +} + +/* + * Check if cached dentry can be trusted. + */ +static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags) +{ + int valid = 0; + struct dentry *parent; + struct inode *dir, *inode; + struct ceph_mds_client *mdsc; + + valid = fscrypt_d_revalidate(dentry, flags); + if (valid <= 0) + return valid; + + if (flags & LOOKUP_RCU) { + parent = READ_ONCE(dentry->d_parent); + dir = d_inode_rcu(parent); + if (!dir) + return -ECHILD; + inode = d_inode_rcu(dentry); + } else { + parent = dget_parent(dentry); + dir = d_inode(parent); + inode = d_inode(dentry); + } + + dout("d_revalidate %p '%pd' inode %p offset 0x%llx nokey %d\n", dentry, + dentry, inode, ceph_dentry(dentry)->offset, + !!(dentry->d_flags & DCACHE_NOKEY_NAME)); + + mdsc = ceph_sb_to_client(dir->i_sb)->mdsc; + + /* always trust cached snapped dentries, snapdir dentry */ + if (ceph_snap(dir) != CEPH_NOSNAP) { + dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry, + dentry, inode); + valid = 1; + } else if (inode && ceph_snap(inode) == CEPH_SNAPDIR) { + valid = 1; + } else { + valid = dentry_lease_is_valid(dentry, flags); + if (valid == -ECHILD) + return valid; + if (valid || dir_lease_is_valid(dir, dentry, mdsc)) { + if (inode) + valid = ceph_is_any_caps(inode); + else + valid = 1; + } + } + + if (!valid) { + struct ceph_mds_request *req; + int op, err; + u32 mask; + + if (flags & LOOKUP_RCU) + return -ECHILD; + + percpu_counter_inc(&mdsc->metric.d_lease_mis); + + op = ceph_snap(dir) == CEPH_SNAPDIR ? + CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP; + req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS); + if (!IS_ERR(req)) { + req->r_dentry = dget(dentry); + req->r_num_caps = 2; + req->r_parent = dir; + ihold(dir); + + mask = CEPH_STAT_CAP_INODE | CEPH_CAP_AUTH_SHARED; + if (ceph_security_xattr_wanted(dir)) + mask |= CEPH_CAP_XATTR_SHARED; + req->r_args.getattr.mask = cpu_to_le32(mask); + + err = ceph_mdsc_do_request(mdsc, NULL, req); + switch (err) { + case 0: + if (d_really_is_positive(dentry) && + d_inode(dentry) == req->r_target_inode) + valid = 1; + break; + case -ENOENT: + if (d_really_is_negative(dentry)) + valid = 1; + fallthrough; + default: + break; + } + ceph_mdsc_put_request(req); + dout("d_revalidate %p lookup result=%d\n", + dentry, err); + } + } else { + percpu_counter_inc(&mdsc->metric.d_lease_hit); + } + + dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid"); + if (!valid) + ceph_dir_clear_complete(dir); + + if (!(flags & LOOKUP_RCU)) + dput(parent); + return valid; +} + +/* + * Delete unused dentry that doesn't have valid lease + * + * Called under dentry->d_lock. + */ +static int ceph_d_delete(const struct dentry *dentry) +{ + struct ceph_dentry_info *di; + + /* won't release caps */ + if (d_really_is_negative(dentry)) + return 0; + if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP) + return 0; + /* vaild lease? */ + di = ceph_dentry(dentry); + if (di) { + if (__dentry_lease_is_valid(di)) + return 0; + if (__dir_lease_try_check(dentry)) + return 0; + } + return 1; +} + +/* + * Release our ceph_dentry_info. + */ +static void ceph_d_release(struct dentry *dentry) +{ + struct ceph_dentry_info *di = ceph_dentry(dentry); + struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb); + + dout("d_release %p\n", dentry); + + atomic64_dec(&fsc->mdsc->metric.total_dentries); + + spin_lock(&dentry->d_lock); + __dentry_lease_unlist(di); + dentry->d_fsdata = NULL; + spin_unlock(&dentry->d_lock); + + ceph_put_mds_session(di->lease_session); + kmem_cache_free(ceph_dentry_cachep, di); +} + +/* + * When the VFS prunes a dentry from the cache, we need to clear the + * complete flag on the parent directory. + * + * Called under dentry->d_lock. + */ +static void ceph_d_prune(struct dentry *dentry) +{ + struct ceph_inode_info *dir_ci; + struct ceph_dentry_info *di; + + dout("ceph_d_prune %pd %p\n", dentry, dentry); + + /* do we have a valid parent? */ + if (IS_ROOT(dentry)) + return; + + /* we hold d_lock, so d_parent is stable */ + dir_ci = ceph_inode(d_inode(dentry->d_parent)); + if (dir_ci->i_vino.snap == CEPH_SNAPDIR) + return; + + /* who calls d_delete() should also disable dcache readdir */ + if (d_really_is_negative(dentry)) + return; + + /* d_fsdata does not get cleared until d_release */ + if (!d_unhashed(dentry)) { + __ceph_dir_clear_complete(dir_ci); + return; + } + + /* Disable dcache readdir just in case that someone called d_drop() + * or d_invalidate(), but MDS didn't revoke CEPH_CAP_FILE_SHARED + * properly (dcache readdir is still enabled) */ + di = ceph_dentry(dentry); + if (di->offset > 0 && + di->lease_shared_gen == atomic_read(&dir_ci->i_shared_gen)) + __ceph_dir_clear_ordered(dir_ci); +} + +/* + * read() on a dir. This weird interface hack only works if mounted + * with '-o dirstat'. + */ +static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size, + loff_t *ppos) +{ + struct ceph_dir_file_info *dfi = file->private_data; + struct inode *inode = file_inode(file); + struct ceph_inode_info *ci = ceph_inode(inode); + int left; + const int bufsize = 1024; + + if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT)) + return -EISDIR; + + if (!dfi->dir_info) { + dfi->dir_info = kmalloc(bufsize, GFP_KERNEL); + if (!dfi->dir_info) + return -ENOMEM; + dfi->dir_info_len = + snprintf(dfi->dir_info, bufsize, + "entries: %20lld\n" + " files: %20lld\n" + " subdirs: %20lld\n" + "rentries: %20lld\n" + " rfiles: %20lld\n" + " rsubdirs: %20lld\n" + "rbytes: %20lld\n" + "rctime: %10lld.%09ld\n", + ci->i_files + ci->i_subdirs, + ci->i_files, + ci->i_subdirs, + ci->i_rfiles + ci->i_rsubdirs, + ci->i_rfiles, + ci->i_rsubdirs, + ci->i_rbytes, + ci->i_rctime.tv_sec, + ci->i_rctime.tv_nsec); + } + + if (*ppos >= dfi->dir_info_len) + return 0; + size = min_t(unsigned, size, dfi->dir_info_len-*ppos); + left = copy_to_user(buf, dfi->dir_info + *ppos, size); + if (left == size) + return -EFAULT; + *ppos += (size - left); + return size - left; +} + + + +/* + * Return name hash for a given dentry. This is dependent on + * the parent directory's hash function. + */ +unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn) +{ + struct ceph_inode_info *dci = ceph_inode(dir); + unsigned hash; + + switch (dci->i_dir_layout.dl_dir_hash) { + case 0: /* for backward compat */ + case CEPH_STR_HASH_LINUX: + return dn->d_name.hash; + + default: + spin_lock(&dn->d_lock); + hash = ceph_str_hash(dci->i_dir_layout.dl_dir_hash, + dn->d_name.name, dn->d_name.len); + spin_unlock(&dn->d_lock); + return hash; + } +} + +WRAP_DIR_ITER(ceph_readdir) // FIXME! +const struct file_operations ceph_dir_fops = { + .read = ceph_read_dir, + .iterate_shared = shared_ceph_readdir, + .llseek = ceph_dir_llseek, + .open = ceph_open, + .release = ceph_release, + .unlocked_ioctl = ceph_ioctl, + .compat_ioctl = compat_ptr_ioctl, + .fsync = ceph_fsync, + .lock = ceph_lock, + .flock = ceph_flock, +}; + +const struct file_operations ceph_snapdir_fops = { + .iterate_shared = shared_ceph_readdir, + .llseek = ceph_dir_llseek, + .open = ceph_open, + .release = ceph_release, +}; + +const struct inode_operations ceph_dir_iops = { + .lookup = ceph_lookup, + .permission = ceph_permission, + .getattr = ceph_getattr, + .setattr = ceph_setattr, + .listxattr = ceph_listxattr, + .get_inode_acl = ceph_get_acl, + .set_acl = ceph_set_acl, + .mknod = ceph_mknod, + .symlink = ceph_symlink, + .mkdir = ceph_mkdir, + .link = ceph_link, + .unlink = ceph_unlink, + .rmdir = ceph_unlink, + .rename = ceph_rename, + .create = ceph_create, + .atomic_open = ceph_atomic_open, +}; + +const struct inode_operations ceph_snapdir_iops = { + .lookup = ceph_lookup, + .permission = ceph_permission, + .getattr = ceph_getattr, + .mkdir = ceph_mkdir, + .rmdir = ceph_unlink, + .rename = ceph_rename, +}; + +const struct dentry_operations ceph_dentry_ops = { + .d_revalidate = ceph_d_revalidate, + .d_delete = ceph_d_delete, + .d_release = ceph_d_release, + .d_prune = ceph_d_prune, + .d_init = ceph_d_init, +}; |