diff options
Diffstat (limited to 'fs/afs/dir.c')
-rw-r--r-- | fs/afs/dir.c | 461 |
1 files changed, 272 insertions, 189 deletions
diff --git a/fs/afs/dir.c b/fs/afs/dir.c index 613a77058263..ab618d32554c 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -130,10 +130,11 @@ struct afs_lookup_cookie { /* * check that a directory page is valid */ -static inline bool afs_dir_check_page(struct inode *dir, struct page *page) +bool afs_dir_check_page(struct inode *dir, struct page *page) { struct afs_dir_page *dbuf; - loff_t latter; + struct afs_vnode *vnode = AFS_FS_I(dir); + loff_t latter, i_size, off; int tmp, qty; #if 0 @@ -150,8 +151,15 @@ static inline bool afs_dir_check_page(struct inode *dir, struct page *page) } #endif - /* determine how many magic numbers there should be in this page */ - latter = dir->i_size - page_offset(page); + /* Determine how many magic numbers there should be in this page, but + * we must take care because the directory may change size under us. + */ + off = page_offset(page); + i_size = i_size_read(dir); + if (i_size <= off) + goto checked; + + latter = i_size - off; if (latter >= PAGE_SIZE) qty = PAGE_SIZE; else @@ -162,13 +170,15 @@ static inline bool afs_dir_check_page(struct inode *dir, struct page *page) dbuf = page_address(page); for (tmp = 0; tmp < qty; tmp++) { if (dbuf->blocks[tmp].pagehdr.magic != AFS_DIR_MAGIC) { - printk("kAFS: %s(%lu): bad magic %d/%d is %04hx\n", + printk("kAFS: %s(%lx): bad magic %d/%d is %04hx\n", __func__, dir->i_ino, tmp, qty, ntohs(dbuf->blocks[tmp].pagehdr.magic)); + trace_afs_dir_check_failed(vnode, off, i_size); goto error; } } +checked: SetPageChecked(page); return true; @@ -183,6 +193,7 @@ error: static inline void afs_dir_put_page(struct page *page) { kunmap(page); + unlock_page(page); put_page(page); } @@ -197,9 +208,10 @@ static struct page *afs_dir_get_page(struct inode *dir, unsigned long index, page = read_cache_page(dir->i_mapping, index, afs_page_filler, key); if (!IS_ERR(page)) { + lock_page(page); kmap(page); if (unlikely(!PageChecked(page))) { - if (PageError(page) || !afs_dir_check_page(dir, page)) + if (PageError(page)) goto fail; } } @@ -384,8 +396,7 @@ out: */ static int afs_readdir(struct file *file, struct dir_context *ctx) { - return afs_dir_iterate(file_inode(file), - ctx, file->private_data); + return afs_dir_iterate(file_inode(file), ctx, afs_file_key(file)); } /* @@ -553,7 +564,7 @@ static struct dentry *afs_lookup(struct inode *dir, struct dentry *dentry, dentry->d_fsdata = (void *)(unsigned long) vnode->status.data_version; /* instantiate the dentry */ - inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL); + inode = afs_iget(dir->i_sb, key, &fid, NULL, NULL, NULL); key_put(key); if (IS_ERR(inode)) { _leave(" = %ld", PTR_ERR(inode)); @@ -581,6 +592,7 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) struct afs_vnode *vnode, *dir; struct afs_fid uninitialized_var(fid); struct dentry *parent; + struct inode *inode; struct key *key; void *dir_version; int ret; @@ -588,30 +600,39 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) if (flags & LOOKUP_RCU) return -ECHILD; - vnode = AFS_FS_I(d_inode(dentry)); - - if (d_really_is_positive(dentry)) + if (d_really_is_positive(dentry)) { + vnode = AFS_FS_I(d_inode(dentry)); _enter("{v={%x:%u} n=%pd fl=%lx},", vnode->fid.vid, vnode->fid.vnode, dentry, vnode->flags); - else + } else { _enter("{neg n=%pd}", dentry); + } key = afs_request_key(AFS_FS_S(dentry->d_sb)->volume->cell); if (IS_ERR(key)) key = NULL; + if (d_really_is_positive(dentry)) { + inode = d_inode(dentry); + if (inode) { + vnode = AFS_FS_I(inode); + afs_validate(vnode, key); + if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) + goto out_bad; + } + } + /* lock down the parent dentry so we can peer at it */ parent = dget_parent(dentry); dir = AFS_FS_I(d_inode(parent)); /* validate the parent directory */ - if (test_bit(AFS_VNODE_MODIFIED, &dir->flags)) - afs_validate(dir, key); + afs_validate(dir, key); if (test_bit(AFS_VNODE_DELETED, &dir->flags)) { _debug("%pd: parent dir deleted", dentry); - goto out_bad; + goto out_bad_parent; } dir_version = (void *) (unsigned long) dir->status.data_version; @@ -626,13 +647,16 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) case 0: /* the filename maps to something */ if (d_really_is_negative(dentry)) - goto out_bad; - if (is_bad_inode(d_inode(dentry))) { + goto out_bad_parent; + inode = d_inode(dentry); + if (is_bad_inode(inode)) { printk("kAFS: afs_d_revalidate: %pd2 has bad inode\n", dentry); - goto out_bad; + goto out_bad_parent; } + vnode = AFS_FS_I(inode); + /* if the vnode ID has changed, then the dirent points to a * different file */ if (fid.vnode != vnode->fid.vnode) { @@ -649,10 +673,10 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) _debug("%pd: file deleted (uq %u -> %u I:%u)", dentry, fid.unique, vnode->fid.unique, - d_inode(dentry)->i_generation); - spin_lock(&vnode->lock); + vnode->vfs_inode.i_generation); + write_seqlock(&vnode->cb_lock); set_bit(AFS_VNODE_DELETED, &vnode->flags); - spin_unlock(&vnode->lock); + write_sequnlock(&vnode->cb_lock); goto not_found; } goto out_valid; @@ -667,7 +691,7 @@ static int afs_d_revalidate(struct dentry *dentry, unsigned int flags) default: _debug("failed to iterate dir %pd: %d", parent, ret); - goto out_bad; + goto out_bad_parent; } out_valid: @@ -683,9 +707,10 @@ not_found: dentry->d_flags |= DCACHE_NFSFS_RENAMED; spin_unlock(&dentry->d_lock); -out_bad: +out_bad_parent: _debug("dropping dentry %pd2", dentry); dput(parent); +out_bad: key_put(key); _leave(" = 0 [bad]"); @@ -727,20 +752,48 @@ static void afs_d_release(struct dentry *dentry) } /* + * Create a new inode for create/mkdir/symlink + */ +static void afs_vnode_new_inode(struct afs_fs_cursor *fc, + struct dentry *new_dentry, + struct afs_fid *newfid, + struct afs_file_status *newstatus, + struct afs_callback *newcb) +{ + struct inode *inode; + + if (fc->ac.error < 0) + return; + + inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key, + newfid, newstatus, newcb, fc->cbi); + if (IS_ERR(inode)) { + /* ENOMEM or EINTR at a really inconvenient time - just abandon + * the new directory on the server. + */ + fc->ac.error = PTR_ERR(inode); + return; + } + + d_instantiate(new_dentry, inode); + if (d_unhashed(new_dentry)) + d_rehash(new_dentry); +} + +/* * create a directory on an AFS filesystem */ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { - struct afs_file_status status; - struct afs_callback cb; - struct afs_server *server; - struct afs_vnode *dvnode, *vnode; - struct afs_fid fid; - struct inode *inode; + struct afs_file_status newstatus; + struct afs_fs_cursor fc; + struct afs_callback newcb; + struct afs_vnode *dvnode = AFS_FS_I(dir); + struct afs_fid newfid; struct key *key; int ret; - dvnode = AFS_FS_I(dir); + mode |= S_IFDIR; _enter("{%x:%u},{%pd},%ho", dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); @@ -751,40 +804,27 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) goto error; } - mode |= S_IFDIR; - ret = afs_vnode_create(dvnode, key, dentry->d_name.name, - mode, &fid, &status, &cb, &server); - if (ret < 0) - goto mkdir_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + afs_fs_create(&fc, dentry->d_name.name, mode, + &newfid, &newstatus, &newcb); + } - inode = afs_iget(dir->i_sb, key, &fid, &status, &cb); - if (IS_ERR(inode)) { - /* ENOMEM at a really inconvenient time - just abandon the new - * directory on the server */ - ret = PTR_ERR(inode); - goto iget_error; + afs_check_for_remote_deletion(&fc, fc.vnode); + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + afs_vnode_new_inode(&fc, dentry, &newfid, &newstatus, &newcb); + ret = afs_end_vnode_operation(&fc); + if (ret < 0) + goto error_key; } - /* apply the status report we've got for the new vnode */ - vnode = AFS_FS_I(inode); - spin_lock(&vnode->lock); - vnode->update_cnt++; - spin_unlock(&vnode->lock); - afs_vnode_finalise_status_update(vnode, server); - afs_put_server(server); - - d_instantiate(dentry, inode); - if (d_unhashed(dentry)) { - _debug("not hashed"); - d_rehash(dentry); - } key_put(key); _leave(" = 0"); return 0; -iget_error: - afs_put_server(server); -mkdir_error: +error_key: key_put(key); error: d_drop(dentry); @@ -793,16 +833,29 @@ error: } /* + * Remove a subdir from a directory. + */ +static void afs_dir_remove_subdir(struct dentry *dentry) +{ + if (d_really_is_positive(dentry)) { + struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); + + clear_nlink(&vnode->vfs_inode); + set_bit(AFS_VNODE_DELETED, &vnode->flags); + clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags); + } +} + +/* * remove a directory from an AFS filesystem */ static int afs_rmdir(struct inode *dir, struct dentry *dentry) { - struct afs_vnode *dvnode, *vnode; + struct afs_fs_cursor fc; + struct afs_vnode *dvnode = AFS_FS_I(dir); struct key *key; int ret; - dvnode = AFS_FS_I(dir); - _enter("{%x:%u},{%pd}", dvnode->fid.vid, dvnode->fid.vnode, dentry); @@ -812,45 +865,69 @@ static int afs_rmdir(struct inode *dir, struct dentry *dentry) goto error; } - ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, true); - if (ret < 0) - goto rmdir_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + afs_fs_remove(&fc, dentry->d_name.name, true); + } - if (d_really_is_positive(dentry)) { - vnode = AFS_FS_I(d_inode(dentry)); - clear_nlink(&vnode->vfs_inode); - set_bit(AFS_VNODE_DELETED, &vnode->flags); - afs_discard_callback_on_delete(vnode); + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + ret = afs_end_vnode_operation(&fc); + if (ret == 0) + afs_dir_remove_subdir(dentry); } key_put(key); - _leave(" = 0"); - return 0; - -rmdir_error: - key_put(key); error: - _leave(" = %d", ret); return ret; } /* - * remove a file from an AFS filesystem + * Remove a link to a file or symlink from a directory. + * + * If the file was not deleted due to excess hard links, the fileserver will + * break the callback promise on the file - if it had one - before it returns + * to us, and if it was deleted, it won't + * + * However, if we didn't have a callback promise outstanding, or it was + * outstanding on a different server, then it won't break it either... + */ +static int afs_dir_remove_link(struct dentry *dentry, struct key *key) +{ + int ret = 0; + + if (d_really_is_positive(dentry)) { + struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); + + if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) + kdebug("AFS_VNODE_DELETED"); + clear_bit(AFS_VNODE_CB_PROMISED, &vnode->flags); + + ret = afs_validate(vnode, key); + if (ret == -ESTALE) + ret = 0; + _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret); + } + + return ret; +} + +/* + * Remove a file or symlink from an AFS filesystem. */ static int afs_unlink(struct inode *dir, struct dentry *dentry) { - struct afs_vnode *dvnode, *vnode; + struct afs_fs_cursor fc; + struct afs_vnode *dvnode = AFS_FS_I(dir), *vnode; struct key *key; int ret; - dvnode = AFS_FS_I(dir); - _enter("{%x:%u},{%pd}", dvnode->fid.vid, dvnode->fid.vnode, dentry); - ret = -ENAMETOOLONG; if (dentry->d_name.len >= AFSNAMEMAX) - goto error; + return -ENAMETOOLONG; key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { @@ -858,44 +935,28 @@ static int afs_unlink(struct inode *dir, struct dentry *dentry) goto error; } + /* Try to make sure we have a callback promise on the victim. */ if (d_really_is_positive(dentry)) { vnode = AFS_FS_I(d_inode(dentry)); - - /* make sure we have a callback promise on the victim */ ret = afs_validate(vnode, key); if (ret < 0) - goto error; + goto error_key; } - ret = afs_vnode_remove(dvnode, key, dentry->d_name.name, false); - if (ret < 0) - goto remove_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + afs_fs_remove(&fc, dentry->d_name.name, false); + } - if (d_really_is_positive(dentry)) { - /* if the file wasn't deleted due to excess hard links, the - * fileserver will break the callback promise on the file - if - * it had one - before it returns to us, and if it was deleted, - * it won't - * - * however, if we didn't have a callback promise outstanding, - * or it was outstanding on a different server, then it won't - * break it either... - */ - vnode = AFS_FS_I(d_inode(dentry)); - if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) - _debug("AFS_VNODE_DELETED"); - if (test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags)) - _debug("AFS_VNODE_CB_BROKEN"); - set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags); - ret = afs_validate(vnode, key); - _debug("nlink %d [val %d]", vnode->vfs_inode.i_nlink, ret); + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + ret = afs_end_vnode_operation(&fc); + if (ret == 0) + ret = afs_dir_remove_link(dentry, key); } - key_put(key); - _leave(" = 0"); - return 0; - -remove_error: +error_key: key_put(key); error: _leave(" = %d", ret); @@ -908,60 +969,50 @@ error: static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { - struct afs_file_status status; - struct afs_callback cb; - struct afs_server *server; - struct afs_vnode *dvnode, *vnode; - struct afs_fid fid; - struct inode *inode; + struct afs_fs_cursor fc; + struct afs_file_status newstatus; + struct afs_callback newcb; + struct afs_vnode *dvnode = dvnode = AFS_FS_I(dir); + struct afs_fid newfid; struct key *key; int ret; - dvnode = AFS_FS_I(dir); + mode |= S_IFREG; _enter("{%x:%u},{%pd},%ho,", dvnode->fid.vid, dvnode->fid.vnode, dentry, mode); + ret = -ENAMETOOLONG; + if (dentry->d_name.len >= AFSNAMEMAX) + goto error; + key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error; } - mode |= S_IFREG; - ret = afs_vnode_create(dvnode, key, dentry->d_name.name, - mode, &fid, &status, &cb, &server); - if (ret < 0) - goto create_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + afs_fs_create(&fc, dentry->d_name.name, mode, + &newfid, &newstatus, &newcb); + } - inode = afs_iget(dir->i_sb, key, &fid, &status, &cb); - if (IS_ERR(inode)) { - /* ENOMEM at a really inconvenient time - just abandon the new - * directory on the server */ - ret = PTR_ERR(inode); - goto iget_error; + afs_check_for_remote_deletion(&fc, fc.vnode); + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + afs_vnode_new_inode(&fc, dentry, &newfid, &newstatus, &newcb); + ret = afs_end_vnode_operation(&fc); + if (ret < 0) + goto error_key; } - /* apply the status report we've got for the new vnode */ - vnode = AFS_FS_I(inode); - spin_lock(&vnode->lock); - vnode->update_cnt++; - spin_unlock(&vnode->lock); - afs_vnode_finalise_status_update(vnode, server); - afs_put_server(server); - - d_instantiate(dentry, inode); - if (d_unhashed(dentry)) { - _debug("not hashed"); - d_rehash(dentry); - } key_put(key); _leave(" = 0"); return 0; -iget_error: - afs_put_server(server); -create_error: +error_key: key_put(key); error: d_drop(dentry); @@ -975,6 +1026,7 @@ error: static int afs_link(struct dentry *from, struct inode *dir, struct dentry *dentry) { + struct afs_fs_cursor fc; struct afs_vnode *dvnode, *vnode; struct key *key; int ret; @@ -987,23 +1039,45 @@ static int afs_link(struct dentry *from, struct inode *dir, dvnode->fid.vid, dvnode->fid.vnode, dentry); + ret = -ENAMETOOLONG; + if (dentry->d_name.len >= AFSNAMEMAX) + goto error; + key = afs_request_key(dvnode->volume->cell); if (IS_ERR(key)) { ret = PTR_ERR(key); goto error; } - ret = afs_vnode_link(dvnode, vnode, key, dentry->d_name.name); - if (ret < 0) - goto link_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + if (mutex_lock_interruptible_nested(&vnode->io_lock, 1) < 0) { + afs_end_vnode_operation(&fc); + return -ERESTARTSYS; + } + + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + fc.cb_break_2 = vnode->cb_break + vnode->cb_s_break; + afs_fs_link(&fc, vnode, dentry->d_name.name); + } + + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + afs_vnode_commit_status(&fc, vnode, fc.cb_break_2); + ihold(&vnode->vfs_inode); + d_instantiate(dentry, &vnode->vfs_inode); + + mutex_unlock(&vnode->io_lock); + ret = afs_end_vnode_operation(&fc); + if (ret < 0) + goto error_key; + } - ihold(&vnode->vfs_inode); - d_instantiate(dentry, &vnode->vfs_inode); key_put(key); _leave(" = 0"); return 0; -link_error: +error_key: key_put(key); error: d_drop(dentry); @@ -1017,20 +1091,21 @@ error: static int afs_symlink(struct inode *dir, struct dentry *dentry, const char *content) { - struct afs_file_status status; - struct afs_server *server; - struct afs_vnode *dvnode, *vnode; - struct afs_fid fid; - struct inode *inode; + struct afs_fs_cursor fc; + struct afs_file_status newstatus; + struct afs_vnode *dvnode = AFS_FS_I(dir); + struct afs_fid newfid; struct key *key; int ret; - dvnode = AFS_FS_I(dir); - _enter("{%x:%u},{%pd},%s", dvnode->fid.vid, dvnode->fid.vnode, dentry, content); + ret = -ENAMETOOLONG; + if (dentry->d_name.len >= AFSNAMEMAX) + goto error; + ret = -EINVAL; if (strlen(content) >= AFSPATHMAX) goto error; @@ -1041,39 +1116,27 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry, goto error; } - ret = afs_vnode_symlink(dvnode, key, dentry->d_name.name, content, - &fid, &status, &server); - if (ret < 0) - goto create_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, dvnode, key)) { + while (afs_select_fileserver(&fc)) { + fc.cb_break = dvnode->cb_break + dvnode->cb_s_break; + afs_fs_symlink(&fc, dentry->d_name.name, content, + &newfid, &newstatus); + } - inode = afs_iget(dir->i_sb, key, &fid, &status, NULL); - if (IS_ERR(inode)) { - /* ENOMEM at a really inconvenient time - just abandon the new - * directory on the server */ - ret = PTR_ERR(inode); - goto iget_error; + afs_check_for_remote_deletion(&fc, fc.vnode); + afs_vnode_commit_status(&fc, dvnode, fc.cb_break); + afs_vnode_new_inode(&fc, dentry, &newfid, &newstatus, NULL); + ret = afs_end_vnode_operation(&fc); + if (ret < 0) + goto error_key; } - /* apply the status report we've got for the new vnode */ - vnode = AFS_FS_I(inode); - spin_lock(&vnode->lock); - vnode->update_cnt++; - spin_unlock(&vnode->lock); - afs_vnode_finalise_status_update(vnode, server); - afs_put_server(server); - - d_instantiate(dentry, inode); - if (d_unhashed(dentry)) { - _debug("not hashed"); - d_rehash(dentry); - } key_put(key); _leave(" = 0"); return 0; -iget_error: - afs_put_server(server); -create_error: +error_key: key_put(key); error: d_drop(dentry); @@ -1088,6 +1151,7 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags) { + struct afs_fs_cursor fc; struct afs_vnode *orig_dvnode, *new_dvnode, *vnode; struct key *key; int ret; @@ -1111,16 +1175,35 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, goto error; } - ret = afs_vnode_rename(orig_dvnode, new_dvnode, key, - old_dentry->d_name.name, - new_dentry->d_name.name); - if (ret < 0) - goto rename_error; + ret = -ERESTARTSYS; + if (afs_begin_vnode_operation(&fc, orig_dvnode, key)) { + if (orig_dvnode != new_dvnode) { + if (mutex_lock_interruptible_nested(&new_dvnode->io_lock, 1) < 0) { + afs_end_vnode_operation(&fc); + return -ERESTARTSYS; + } + } + while (afs_select_fileserver(&fc)) { + fc.cb_break = orig_dvnode->cb_break + orig_dvnode->cb_s_break; + fc.cb_break_2 = new_dvnode->cb_break + new_dvnode->cb_s_break; + afs_fs_rename(&fc, old_dentry->d_name.name, + new_dvnode, new_dentry->d_name.name); + } + + afs_vnode_commit_status(&fc, orig_dvnode, fc.cb_break); + afs_vnode_commit_status(&fc, new_dvnode, fc.cb_break_2); + if (orig_dvnode != new_dvnode) + mutex_unlock(&new_dvnode->io_lock); + ret = afs_end_vnode_operation(&fc); + if (ret < 0) + goto error_key; + } + key_put(key); _leave(" = 0"); return 0; -rename_error: +error_key: key_put(key); error: d_drop(new_dentry); |