/* * Copyright (c) 2002 Red Hat, Inc. All rights reserved. * * This software may be freely redistributed under the terms of the * GNU General Public License. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * Authors: David Woodhouse * David Howells * */ #include #include #include #include #include #include #include #include #include #include "internal.h" #include "afs_fs.h" static const struct inode_operations afs_symlink_inode_operations = { .get_link = page_get_link, .listxattr = afs_listxattr, }; static noinline void dump_vnode(struct afs_vnode *vnode, struct afs_vnode *parent_vnode) { static unsigned long once_only; pr_warn("kAFS: AFS vnode with undefined type %u\n", vnode->status.type); pr_warn("kAFS: A=%d m=%o s=%llx v=%llx\n", vnode->status.abort_code, vnode->status.mode, vnode->status.size, vnode->status.data_version); pr_warn("kAFS: vnode %llx:%llx:%x\n", vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique); if (parent_vnode) pr_warn("kAFS: dir %llx:%llx:%x\n", parent_vnode->fid.vid, parent_vnode->fid.vnode, parent_vnode->fid.unique); if (!test_and_set_bit(0, &once_only)) dump_stack(); } /* * Set the file size and block count. Estimate the number of 512 bytes blocks * used, rounded up to nearest 1K for consistency with other AFS clients. */ static void afs_set_i_size(struct afs_vnode *vnode, u64 size) { i_size_write(&vnode->vfs_inode, size); vnode->vfs_inode.i_blocks = ((size + 1023) >> 10) << 1; } /* * Initialise an inode from the vnode status. */ static int afs_inode_init_from_status(struct afs_operation *op, struct afs_vnode_param *vp, struct afs_vnode *vnode) { struct afs_file_status *status = &vp->scb.status; struct inode *inode = AFS_VNODE_TO_I(vnode); struct timespec64 t; _enter("{%llx:%llu.%u} %s", vp->fid.vid, vp->fid.vnode, vp->fid.unique, op->type ? op->type->name : "???"); _debug("FS: ft=%d lk=%d sz=%llu ver=%Lu mod=%hu", status->type, status->nlink, (unsigned long long) status->size, status->data_version, status->mode); write_seqlock(&vnode->cb_lock); vnode->cb_v_break = op->cb_v_break; vnode->cb_s_break = op->cb_s_break; vnode->status = *status; t = status->mtime_client; inode->i_ctime = t; inode->i_mtime = t; inode->i_atime = t; inode->i_flags |= S_NOATIME; inode->i_uid = make_kuid(&init_user_ns, status->owner); inode->i_gid = make_kgid(&init_user_ns, status->group); set_nlink(&vnode->vfs_inode, status->nlink); switch (status->type) { case AFS_FTYPE_FILE: inode->i_mode = S_IFREG | status->mode; inode->i_op = &afs_file_inode_operations; inode->i_fop = &afs_file_operations; inode->i_mapping->a_ops = &afs_fs_aops; break; case AFS_FTYPE_DIR: inode->i_mode = S_IFDIR | status->mode; inode->i_op = &afs_dir_inode_operations; inode->i_fop = &afs_dir_file_operations; inode->i_mapping->a_ops = &afs_dir_aops; break; case AFS_FTYPE_SYMLINK: /* Symlinks with a mode of 0644 are actually mountpoints. */ if ((status->mode & 0777) == 0644) { inode->i_flags |= S_AUTOMOUNT; set_bit(AFS_VNODE_MOUNTPOINT, &vnode->flags); inode->i_mode = S_IFDIR | 0555; inode->i_op = &afs_mntpt_inode_operations; inode->i_fop = &afs_mntpt_file_operations; inode->i_mapping->a_ops = &afs_fs_aops; } else { inode->i_mode = S_IFLNK | status->mode; inode->i_op = &afs_symlink_inode_operations; inode->i_mapping->a_ops = &afs_fs_aops; } inode_nohighmem(inode); break; default: dump_vnode(vnode, op->file[0].vnode != vnode ? op->file[0].vnode : NULL); write_sequnlock(&vnode->cb_lock); return afs_protocol_error(NULL, afs_eproto_file_type); } afs_set_i_size(vnode, status->size); vnode->invalid_before = status->data_version; inode_set_iversion_raw(&vnode->vfs_inode, status->data_version); if (!vp->scb.have_cb) { /* it's a symlink we just created (the fileserver * didn't give us a callback) */ vnode->cb_expires_at = ktime_get_real_seconds(); } else { vnode->cb_expires_at = vp->scb.callback.expires_at; vnode->cb_server = op->server; set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags); } write_sequnlock(&vnode->cb_lock); return 0; } /* * Update the core inode struct from a returned status record. */ static void afs_apply_status(struct afs_operation *op, struct afs_vnode_param *vp) { struct afs_file_status *status = &vp->scb.status; struct afs_vnode *vnode = vp->vnode; struct inode *inode = &vnode->vfs_inode; struct timespec64 t; umode_t mode; bool data_changed = false; bool change_size = false; _enter("{%llx:%llu.%u} %s", vp->fid.vid, vp->fid.vnode, vp->fid.unique, op->type ? op->type->name : "???"); BUG_ON(test_bit(AFS_VNODE_UNSET, &vnode->flags)); if (status->type != vnode->status.type) { pr_warn("Vnode %llx:%llx:%x changed type %u to %u\n", vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique, status->type, vnode->status.type); afs_protocol_error(NULL, afs_eproto_bad_status); return; } if (status->nlink != vnode->status.nlink) set_nlink(inode, status->nlink); if (status->owner != vnode->status.owner) inode->i_uid = make_kuid(&init_user_ns, status->owner); if (status->group != vnode->status.group) inode->i_gid = make_kgid(&init_user_ns, status->group); if (status->mode != vnode->status.mode) { mode = inode->i_mode; mode &= ~S_IALLUGO; mode |= status->mode; WRITE_ONCE(inode->i_mode, mode); } t = status->mtime_client; inode->i_mtime = t; if (vp->update_ctime) inode->i_ctime = op->ctime; if (vnode->status.data_version != status->data_version) data_changed = true; vnode->status = *status; if (vp->dv_before + vp->dv_delta != status->data_version) { if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) pr_warn("kAFS: vnode modified {%llx:%llu} %llx->%llx %s\n", vnode->fid.vid, vnode->fid.vnode, (unsigned long long)vp->dv_before + vp->dv_delta, (unsigned long long)status->data_version, op->type ? op->type->name : "???"); vnode->invalid_before = status->data_version; if (vnode->status.type == AFS_FTYPE_DIR) { if (test_and_clear_bit(AFS_VNODE_DIR_VALID, &vnode->flags)) afs_stat_v(vnode, n_inval); } else { set_bit(AFS_VNODE_ZAP_DATA, &vnode->flags); } change_size = true; } else if (vnode->status.type == AFS_FTYPE_DIR) { /* Expected directory change is handled elsewhere so * that we can locally edit the directory and save on a * download. */ if (test_bit(AFS_VNODE_DIR_VALID, &vnode->flags)) data_changed = false; change_size = true; } if (data_changed) { inode_set_iversion_raw(inode, status->data_version); /* Only update the size if the data version jumped. If the * file is being modified locally, then we might have our own * idea of what the size should be that's not the same as * what's on the server. */ if (change_size) { afs_set_i_size(vnode, status->size); inode->i_ctime = t; inode->i_atime = t; } } } /* * Apply a callback to a vnode. */ static void afs_apply_callback(struct afs_operation *op, struct afs_vnode_param *vp) { struct afs_callback *cb = &vp->scb.callback; struct afs_vnode *vnode = vp->vnode; if (!afs_cb_is_broken(vp->cb_break_before, vnode)) { vnode->cb_expires_at = cb->expires_at; vnode->cb_server = op->server; set_bit(AFS_VNODE_CB_PROMISED, &vnode->flags); } } /* * Apply the received status and callback to an inode all in the same critical * section to avoid races with afs_validate(). */ void afs_vnode_commit_status(struct afs_operation *op, struct afs_vnode_param *vp) { struct afs_vnode *vnode = vp->vnode; _enter(""); ASSERTCMP(op->error, ==, 0); write_seqlock(&vnode->cb_lock); if (vp->scb.have_error) { if (vp->scb.status.abort_code == VNOVNODE) { set_bit(AFS_VNODE_DELETED, &vnode->flags); clear_nlink(&vnode->vfs_inode); __afs_break_callback(vnode, afs_cb_break_for_deleted); } } else { if (vp->scb.have_status) afs_apply_status(op, vp); if (vp->scb.have_cb) afs_apply_callback(op, vp); } write_sequnlock(&vnode->cb_lock); if (op->error == 0 && vp->scb.have_status) afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb); } static void afs_fetch_status_success(struct afs_operation *op) { struct afs_vnode_param *vp = &op->file[0]; struct afs_vnode *vnode = vp->vnode; int ret; if (vnode->vfs_inode.i_state & I_NEW) { ret = afs_inode_init_from_status(op, vp, vnode); op->error = ret; if (ret == 0) afs_cache_permit(vnode, op->key, vp->cb_break_before, &vp->scb); } else { afs_vnode_commit_status(op, vp); } } static const struct afs_operation_ops afs_fetch_status_operation = { .issue_afs_rpc = afs_fs_fetch_status, .issue_yfs_rpc = yfs_fs_fetch_status, .success = afs_fetch_status_success, }; /* * Fetch file status from the volume. */ int afs_fetch_status(struct afs_vnode *vnode, struct key *key, bool is_new, afs_access_t *_caller_access) { struct afs_operation *op; _enter("%s,{%llx:%llu.%u,S=%lx}", vnode->volume->name, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique, vnode->flags); op = afs_alloc_operation(key, vnode->volume); if (IS_ERR(op)) return PTR_ERR(op); afs_op_set_vnode(op, 0, vnode); op->nr_files = 1; op->ops = &afs_fetch_status_operation; afs_begin_vnode_operation(op); afs_wait_for_operation(op); if (_caller_access) *_caller_access = op->file[0].scb.status.caller_access; return afs_put_operation(op); } /* * ilookup() comparator */ int afs_ilookup5_test_by_fid(struct inode *inode, void *opaque) { struct afs_vnode *vnode = AFS_FS_I(inode); struct afs_fid *fid = opaque; return (fid->vnode == vnode->fid.vnode && fid->vnode_hi == vnode->fid.vnode_hi && fid->unique == vnode->fid.unique); } /* * iget5() comparator */ static int afs_iget5_test(struct inode *inode, void *opaque) { struct afs_vnode_param *vp = opaque; //struct afs_vnode *vnode = AFS_FS_I(inode); return afs_ilookup5_test_by_fid(inode, &vp->fid); } /* * iget5() inode initialiser */ static int afs_iget5_set(struct inode *inode, void *opaque) { struct afs_vnode_param *vp = opaque; struct afs_super_info *as = AFS_FS_S(inode->i_sb); struct afs_vnode *vnode = AFS_FS_I(inode); vnode->volume = as->volume; vnode->fid = vp->fid; /* YFS supports 96-bit vnode IDs, but Linux only supports * 64-bit inode numbers. */ inode->i_ino = vnode->fid.vnode; inode->i_generation = vnode->fid.unique; return 0; } /* * Get a cache cookie for an inode. */ static void afs_get_inode_cache(struct afs_vnode *vnode) { #ifdef CONFIG_AFS_FSCACHE struct { u32 vnode_id; u32 unique; u32 vnode_id_ext[2]; /* Allow for a 96-bit key */ } __packed key; struct afs_vnode_cache_aux aux; if (vnode->status.type == AFS_FTYPE_DIR) { vnode->cache = NULL; return; } key.vnode_id = vnode->fid.vnode; key.unique = vnode->fid.unique; key.vnode_id_ext[0] = vnode->fid.vnode >> 32; key.vnode_id_ext[1] = vnode->fid.vnode_hi; aux.data_version = vnode->status.data_version; vnode->cache = fscache_acquire_cookie(vnode->volume->cache, &afs_vnode_cache_index_def, &key, sizeof(key), &aux, sizeof(aux), vnode, vnode->status.size, true); #endif } /* * inode retrieval */ struct inode *afs_iget(struct afs_operation *op, struct afs_vnode_param *vp) { struct afs_vnode_param *dvp = &op->file[0]; struct super_block *sb = dvp->vnode->vfs_inode.i_sb; struct afs_vnode *vnode; struct inode *inode; int ret; _enter(",{%llx:%llu.%u},,", vp->fid.vid, vp->fid.vnode, vp->fid.unique); inode = iget5_locked(sb, vp->fid.vnode, afs_iget5_test, afs_iget5_set, vp); if (!inode) { _leave(" = -ENOMEM"); return ERR_PTR(-ENOMEM); } vnode = AFS_FS_I(inode); _debug("GOT INODE %p { vl=%llx vn=%llx, u=%x }", inode, vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique); /* deal with an existing inode */ if (!(inode->i_state & I_NEW)) { _leave(" = %p", inode); return inode; } ret = afs_inode_init_from_status(op, vp, vnode); if (ret < 0) goto bad_inode; afs_get_inode_cache(vnode); /* success */ clear_bit(AFS_VNODE_UNSET, &vnode->flags); unlock_new_inode(inode); _leave(" = %p", inode); return inode; /* failure */ bad_inode: iget_failed(inode); _leave(" = %d [bad]", ret); return ERR_PTR(ret); } static int afs_iget5_set_root(struct inode *inode, void *opaque) { struct afs_super_info *as = AFS_FS_S(inode->i_sb); struct afs_vnode *vnode = AFS_FS_I(inode); vnode->volume = as->volume; vnode->fid.vid = as->volume->vid, vnode->fid.vnode = 1; vnode->fid.unique = 1; inode->i_ino = 1; inode->i_generation = 1; return 0; } /* * Set up the root inode for a volume. This is always vnode 1, unique 1 within * the volume. */ struct inode *afs_root_iget(struct super_block *sb, struct key *key) { struct afs_super_info *as = AFS_FS_S(sb); struct afs_operation *op; struct afs_vnode *vnode; struct inode *inode; int ret; _enter(",{%llx},,", as->volume->vid); inode = iget5_locked(sb, 1, NULL, afs_iget5_set_root, NULL); if (!inode) { _leave(" = -ENOMEM"); return ERR_PTR(-ENOMEM); } _debug("GOT ROOT INODE %p { vl=%llx }", inode, as->volume->vid); BUG_ON(!(inode->i_state & I_NEW)); vnode = AFS_FS_I(inode); vnode->cb_v_break = as->volume->cb_v_break, op = afs_alloc_operation(key, as->volume); if (IS_ERR(op)) { ret = PTR_ERR(op); goto error; } afs_op_set_vnode(op, 0, vnode); op->nr_files = 1; op->ops = &afs_fetch_status_operation; ret = afs_do_sync_operation(op); if (ret < 0) goto error; afs_get_inode_cache(vnode); clear_bit(AFS_VNODE_UNSET, &vnode->flags); unlock_new_inode(inode); _leave(" = %p", inode); return inode; error: iget_failed(inode); _leave(" = %d [bad]", ret); return ERR_PTR(ret); } /* * mark the data attached to an inode as obsolete due to a write on the server * - might also want to ditch all the outstanding writes and dirty pages */ static void afs_zap_data(struct afs_vnode *vnode) { _enter("{%llx:%llu}", vnode->fid.vid, vnode->fid.vnode); #ifdef CONFIG_AFS_FSCACHE fscache_invalidate(vnode->cache); #endif /* nuke all the non-dirty pages that aren't locked, mapped or being * written back in a regular file and completely discard the pages in a * directory or symlink */ if (S_ISREG(vnode->vfs_inode.i_mode)) invalidate_remote_inode(&vnode->vfs_inode); else invalidate_inode_pages2(vnode->vfs_inode.i_mapping); } /* * Get the server reinit counter for a vnode's current server. */ static bool afs_get_s_break_rcu(struct afs_vnode *vnode, unsigned int *_s_break) { struct afs_server_list *slist = rcu_dereference(vnode->volume->servers); struct afs_server *server; int i; for (i = 0; i < slist->nr_servers; i++) { server = slist->servers[i].server; if (server == vnode->cb_server) { *_s_break = READ_ONCE(server->cb_s_break); return true; } } return false; } /* * Check the validity of a vnode/inode. */ bool afs_check_validity(struct afs_vnode *vnode) { struct afs_volume *volume = vnode->volume; enum afs_cb_break_reason need_clear = afs_cb_break_no_break; time64_t now = ktime_get_real_seconds(); bool valid; unsigned int cb_break, cb_s_break, cb_v_break; int seq = 0; do { read_seqbegin_or_lock(&vnode->cb_lock, &seq); cb_v_break = READ_ONCE(volume->cb_v_break); cb_break = vnode->cb_break; if (test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags) && afs_get_s_break_rcu(vnode, &cb_s_break)) { if (vnode->cb_s_break != cb_s_break || vnode->cb_v_break != cb_v_break) { vnode->cb_s_break = cb_s_break; vnode->cb_v_break = cb_v_break; need_clear = afs_cb_break_for_vsbreak; valid = false; } else if (test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) { need_clear = afs_cb_break_for_zap; valid = false; } else if (vnode->cb_expires_at - 10 <= now) { need_clear = afs_cb_break_for_lapsed; valid = false; } else { valid = true; } } else if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { valid = true; } else { vnode->cb_v_break = cb_v_break; valid = false; } } while (need_seqretry(&vnode->cb_lock, seq)); done_seqretry(&vnode->cb_lock, seq); if (need_clear != afs_cb_break_no_break) { write_seqlock(&vnode->cb_lock); if (cb_break == vnode->cb_break) __afs_break_callback(vnode, need_clear); else trace_afs_cb_miss(&vnode->fid, need_clear); write_sequnlock(&vnode->cb_lock); valid = false; } return valid; } /* * validate a vnode/inode * - there are several things we need to check * - parent dir data changes (rm, rmdir, rename, mkdir, create, link, * symlink) * - parent dir metadata changed (security changes) * - dentry data changed (write, truncate) * - dentry metadata changed (security changes) */ int afs_validate(struct afs_vnode *vnode, struct key *key) { bool valid; int ret; _enter("{v={%llx:%llu} fl=%lx},%x", vnode->fid.vid, vnode->fid.vnode, vnode->flags, key_serial(key)); rcu_read_lock(); valid = afs_check_validity(vnode); rcu_read_unlock(); if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) clear_nlink(&vnode->vfs_inode); if (valid) goto valid; down_write(&vnode->validate_lock); /* if the promise has expired, we need to check the server again to get * a new promise - note that if the (parent) directory's metadata was * changed then the security may be different and we may no longer have * access */ if (!test_bit(AFS_VNODE_CB_PROMISED, &vnode->flags)) { _debug("not promised"); ret = afs_fetch_status(vnode, key, false, NULL); if (ret < 0) { if (ret == -ENOENT) { set_bit(AFS_VNODE_DELETED, &vnode->flags); ret = -ESTALE; } goto error_unlock; } _debug("new promise [fl=%lx]", vnode->flags); } if (test_bit(AFS_VNODE_DELETED, &vnode->flags)) { _debug("file already deleted"); ret = -ESTALE; goto error_unlock; } /* if the vnode's data version number changed then its contents are * different */ if (test_and_clear_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) afs_zap_data(vnode); up_write(&vnode->validate_lock); valid: _leave(" = 0"); return 0; error_unlock: up_write(&vnode->validate_lock); _leave(" = %d", ret); return ret; } /* * read the attributes of an inode */ int afs_getattr(const struct path *path, struct kstat *stat, u32 request_mask, unsigned int query_flags) { struct inode *inode = d_inode(path->dentry); struct afs_vnode *vnode = AFS_FS_I(inode); int seq = 0; _enter("{ ino=%lu v=%u }", inode->i_ino, inode->i_generation); do { read_seqbegin_or_lock(&vnode->cb_lock, &seq); generic_fillattr(inode, stat); } while (need_seqretry(&vnode->cb_lock, seq)); done_seqretry(&vnode->cb_lock, seq); return 0; } /* * discard an AFS inode */ int afs_drop_inode(struct inode *inode) { _enter(""); if (test_bit(AFS_VNODE_PSEUDODIR, &AFS_FS_I(inode)->flags)) return generic_delete_inode(inode); else return generic_drop_inode(inode); } /* * clear an AFS inode */ void afs_evict_inode(struct inode *inode) { struct afs_vnode *vnode; vnode = AFS_FS_I(inode); _enter("{%llx:%llu.%d}", vnode->fid.vid, vnode->fid.vnode, vnode->fid.unique); _debug("CLEAR INODE %p", inode); ASSERTCMP(inode->i_ino, ==, vnode->fid.vnode); truncate_inode_pages_final(&inode->i_data); clear_inode(inode); while (!list_empty(&vnode->wb_keys)) { struct afs_wb_key *wbk = list_entry(vnode->wb_keys.next, struct afs_wb_key, vnode_link); list_del(&wbk->vnode_link); afs_put_wb_key(wbk); } #ifdef CONFIG_AFS_FSCACHE { struct afs_vnode_cache_aux aux; aux.data_version = vnode->status.data_version; fscache_relinquish_cookie(vnode->cache, &aux, test_bit(AFS_VNODE_DELETED, &vnode->flags)); vnode->cache = NULL; } #endif afs_prune_wb_keys(vnode); afs_put_permits(rcu_access_pointer(vnode->permit_cache)); key_put(vnode->silly_key); vnode->silly_key = NULL; key_put(vnode->lock_key); vnode->lock_key = NULL; _leave(""); } static void afs_setattr_success(struct afs_operation *op) { afs_vnode_commit_status(op, &op->file[0]); } static const struct afs_operation_ops afs_setattr_operation = { .issue_afs_rpc = afs_fs_setattr, .issue_yfs_rpc = yfs_fs_setattr, .success = afs_setattr_success, }; /* * set the attributes of an inode */ int afs_setattr(struct dentry *dentry, struct iattr *attr) { struct afs_operation *op; struct afs_vnode *vnode = AFS_FS_I(d_inode(dentry)); _enter("{%llx:%llu},{n=%pd},%x", vnode->fid.vid, vnode->fid.vnode, dentry, attr->ia_valid); if (!(attr->ia_valid & (ATTR_SIZE | ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_MTIME | ATTR_MTIME_SET | ATTR_TIMES_SET | ATTR_TOUCH))) { _leave(" = 0 [unsupported]"); return 0; } /* flush any dirty data outstanding on a regular file */ if (S_ISREG(vnode->vfs_inode.i_mode)) filemap_write_and_wait(vnode->vfs_inode.i_mapping); op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ? afs_file_key(attr->ia_file) : NULL), vnode->volume); if (IS_ERR(op)) return PTR_ERR(op); afs_op_set_vnode(op, 0, vnode); op->setattr.attr = attr; if (attr->ia_valid & ATTR_SIZE) op->file[0].dv_delta = 1; op->ctime = attr->ia_ctime; op->file[0].update_ctime = 1; op->ops = &afs_setattr_operation; return afs_do_sync_operation(op); }