diff --git a/fs/afs/cell.c b/fs/afs/cell.c index 1858c91169e4..9bb921d120d0 100644 --- a/fs/afs/cell.c +++ b/fs/afs/cell.c @@ -207,13 +207,8 @@ struct afs_cell *afs_lookup_cell(struct afs_net *net, rcu_read_lock(); cell = afs_lookup_cell_rcu(net, name, namesz); rcu_read_unlock(); - if (!IS_ERR(cell)) { - if (excl) { - afs_put_cell(net, cell); - return ERR_PTR(-EEXIST); - } + if (!IS_ERR(cell)) goto wait_for_cell; - } } /* Assume we're probably going to create a cell and preallocate and diff --git a/fs/afs/dir.c b/fs/afs/dir.c index ab618d32554c..ff8d5bf4354f 100644 --- a/fs/afs/dir.c +++ b/fs/afs/dir.c @@ -765,6 +765,8 @@ static void afs_vnode_new_inode(struct afs_fs_cursor *fc, if (fc->ac.error < 0) return; + d_drop(new_dentry); + inode = afs_iget(fc->vnode->vfs_inode.i_sb, fc->key, newfid, newstatus, newcb, fc->cbi); if (IS_ERR(inode)) { @@ -775,9 +777,7 @@ static void afs_vnode_new_inode(struct afs_fs_cursor *fc, return; } - d_instantiate(new_dentry, inode); - if (d_unhashed(new_dentry)) - d_rehash(new_dentry); + d_add(new_dentry, inode); } /* @@ -818,6 +818,8 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; + } else { + goto error_key; } key_put(key); @@ -972,7 +974,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, 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_vnode *dvnode = AFS_FS_I(dir); struct afs_fid newfid; struct key *key; int ret; @@ -1006,6 +1008,8 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode, ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; + } else { + goto error_key; } key_put(key); @@ -1053,7 +1057,7 @@ static int afs_link(struct dentry *from, struct inode *dir, 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; + goto error_key; } while (afs_select_fileserver(&fc)) { @@ -1071,6 +1075,8 @@ static int afs_link(struct dentry *from, struct inode *dir, ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; + } else { + goto error_key; } key_put(key); @@ -1130,6 +1136,8 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry, ret = afs_end_vnode_operation(&fc); if (ret < 0) goto error_key; + } else { + goto error_key; } key_put(key); @@ -1180,7 +1188,7 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, if (orig_dvnode != new_dvnode) { if (mutex_lock_interruptible_nested(&new_dvnode->io_lock, 1) < 0) { afs_end_vnode_operation(&fc); - return -ERESTARTSYS; + goto error_key; } } while (afs_select_fileserver(&fc)) { @@ -1199,14 +1207,9 @@ static int afs_rename(struct inode *old_dir, struct dentry *old_dentry, goto error_key; } - key_put(key); - _leave(" = 0"); - return 0; - error_key: key_put(key); error: - d_drop(new_dentry); _leave(" = %d", ret); return ret; } diff --git a/fs/afs/flock.c b/fs/afs/flock.c index 7571a5dfd5a3..c40ba2fe3cbe 100644 --- a/fs/afs/flock.c +++ b/fs/afs/flock.c @@ -170,7 +170,7 @@ void afs_lock_work(struct work_struct *work) { struct afs_vnode *vnode = container_of(work, struct afs_vnode, lock_work.work); - struct file_lock *fl; + struct file_lock *fl, *next; afs_lock_type_t type; struct key *key; int ret; @@ -179,117 +179,136 @@ void afs_lock_work(struct work_struct *work) spin_lock(&vnode->lock); - if (test_bit(AFS_VNODE_UNLOCKING, &vnode->flags)) { +again: + _debug("wstate %u for %p", vnode->lock_state, vnode); + switch (vnode->lock_state) { + case AFS_VNODE_LOCK_NEED_UNLOCK: _debug("unlock"); + vnode->lock_state = AFS_VNODE_LOCK_UNLOCKING; spin_unlock(&vnode->lock); /* attempt to release the server lock; if it fails, we just - * wait 5 minutes and it'll time out anyway */ - ret = afs_release_lock(vnode, vnode->unlock_key); + * wait 5 minutes and it'll expire anyway */ + ret = afs_release_lock(vnode, vnode->lock_key); if (ret < 0) printk(KERN_WARNING "AFS:" " Failed to release lock on {%x:%x} error %d\n", vnode->fid.vid, vnode->fid.vnode, ret); spin_lock(&vnode->lock); - key_put(vnode->unlock_key); - vnode->unlock_key = NULL; - clear_bit(AFS_VNODE_UNLOCKING, &vnode->flags); - } + key_put(vnode->lock_key); + vnode->lock_key = NULL; + vnode->lock_state = AFS_VNODE_LOCK_NONE; - /* if we've got a lock, then it must be time to extend that lock as AFS - * locks time out after 5 minutes */ - if (!list_empty(&vnode->granted_locks)) { + if (list_empty(&vnode->pending_locks)) { + spin_unlock(&vnode->lock); + return; + } + + /* The new front of the queue now owns the state variables. */ + next = list_entry(vnode->pending_locks.next, + struct file_lock, fl_u.afs.link); + vnode->lock_key = afs_file_key(next->fl_file); + vnode->lock_type = (next->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; + vnode->lock_state = AFS_VNODE_LOCK_WAITING_FOR_CB; + goto again; + + /* If we've already got a lock, then it must be time to extend that + * lock as AFS locks time out after 5 minutes. + */ + case AFS_VNODE_LOCK_GRANTED: _debug("extend"); - if (test_and_set_bit(AFS_VNODE_LOCKING, &vnode->flags)) - BUG(); - fl = list_entry(vnode->granted_locks.next, - struct file_lock, fl_u.afs.link); - key = key_get(afs_file_key(fl->fl_file)); + ASSERT(!list_empty(&vnode->granted_locks)); + + key = key_get(vnode->lock_key); + vnode->lock_state = AFS_VNODE_LOCK_EXTENDING; spin_unlock(&vnode->lock); - ret = afs_extend_lock(vnode, key); - clear_bit(AFS_VNODE_LOCKING, &vnode->flags); + ret = afs_extend_lock(vnode, key); /* RPC */ key_put(key); - switch (ret) { - case 0: + + if (ret < 0) + pr_warning("AFS: Failed to extend lock on {%x:%x} error %d\n", + vnode->fid.vid, vnode->fid.vnode, ret); + + spin_lock(&vnode->lock); + + if (vnode->lock_state != AFS_VNODE_LOCK_EXTENDING) + goto again; + vnode->lock_state = AFS_VNODE_LOCK_GRANTED; + + if (ret == 0) afs_schedule_lock_extension(vnode); - break; - default: - /* ummm... we failed to extend the lock - retry - * extension shortly */ - printk(KERN_WARNING "AFS:" - " Failed to extend lock on {%x:%x} error %d\n", - vnode->fid.vid, vnode->fid.vnode, ret); + else queue_delayed_work(afs_lock_manager, &vnode->lock_work, HZ * 10); - break; - } - _leave(" [extend]"); + spin_unlock(&vnode->lock); + _leave(" [ext]"); return; - } - /* if we don't have a granted lock, then we must've been called back by - * the server, and so if might be possible to get a lock we're - * currently waiting for */ - if (!list_empty(&vnode->pending_locks)) { + /* If we don't have a granted lock, then we must've been called + * back by the server, and so if might be possible to get a + * lock we're currently waiting for. + */ + case AFS_VNODE_LOCK_WAITING_FOR_CB: _debug("get"); - if (test_and_set_bit(AFS_VNODE_LOCKING, &vnode->flags)) - BUG(); - fl = list_entry(vnode->pending_locks.next, - struct file_lock, fl_u.afs.link); - key = key_get(afs_file_key(fl->fl_file)); - type = (fl->fl_type == F_RDLCK) ? - AFS_LOCK_READ : AFS_LOCK_WRITE; + key = key_get(vnode->lock_key); + type = vnode->lock_type; + vnode->lock_state = AFS_VNODE_LOCK_SETTING; spin_unlock(&vnode->lock); - ret = afs_set_lock(vnode, key, type); - clear_bit(AFS_VNODE_LOCKING, &vnode->flags); + ret = afs_set_lock(vnode, key, type); /* RPC */ + key_put(key); + + spin_lock(&vnode->lock); switch (ret) { case -EWOULDBLOCK: _debug("blocked"); break; case 0: _debug("acquired"); - if (type == AFS_LOCK_READ) - set_bit(AFS_VNODE_READLOCKED, &vnode->flags); - else - set_bit(AFS_VNODE_WRITELOCKED, &vnode->flags); - ret = AFS_LOCK_GRANTED; + vnode->lock_state = AFS_VNODE_LOCK_GRANTED; + /* Fall through */ default: - spin_lock(&vnode->lock); - /* the pending lock may have been withdrawn due to a - * signal */ - if (list_entry(vnode->pending_locks.next, - struct file_lock, fl_u.afs.link) == fl) { - fl->fl_u.afs.state = ret; - if (ret == AFS_LOCK_GRANTED) - afs_grant_locks(vnode, fl); - else - list_del_init(&fl->fl_u.afs.link); - wake_up(&fl->fl_wait); - spin_unlock(&vnode->lock); - } else { + /* Pass the lock or the error onto the first locker in + * the list - if they're looking for this type of lock. + * If they're not, we assume that whoever asked for it + * took a signal. + */ + if (list_empty(&vnode->pending_locks)) { _debug("withdrawn"); - clear_bit(AFS_VNODE_READLOCKED, &vnode->flags); - clear_bit(AFS_VNODE_WRITELOCKED, &vnode->flags); - spin_unlock(&vnode->lock); - afs_release_lock(vnode, key); - if (!list_empty(&vnode->pending_locks)) - afs_lock_may_be_available(vnode); + vnode->lock_state = AFS_VNODE_LOCK_NEED_UNLOCK; + goto again; } - break; + + fl = list_entry(vnode->pending_locks.next, + struct file_lock, fl_u.afs.link); + type = (fl->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; + if (vnode->lock_type != type) { + _debug("changed"); + vnode->lock_state = AFS_VNODE_LOCK_NEED_UNLOCK; + goto again; + } + + fl->fl_u.afs.state = ret; + if (ret == 0) + afs_grant_locks(vnode, fl); + else + list_del_init(&fl->fl_u.afs.link); + wake_up(&fl->fl_wait); + spin_unlock(&vnode->lock); + _leave(" [granted]"); + return; } - key_put(key); - _leave(" [pend]"); + + default: + /* Looks like a lock request was withdrawn. */ + spin_unlock(&vnode->lock); + _leave(" [no]"); return; } - - /* looks like the lock request was withdrawn on a signal */ - spin_unlock(&vnode->lock); - _leave(" [no locks]"); } /* @@ -298,15 +317,105 @@ void afs_lock_work(struct work_struct *work) * AF_RXRPC * - the caller must hold the vnode lock */ -static void afs_defer_unlock(struct afs_vnode *vnode, struct key *key) +static void afs_defer_unlock(struct afs_vnode *vnode) { - cancel_delayed_work(&vnode->lock_work); - if (!test_and_clear_bit(AFS_VNODE_READLOCKED, &vnode->flags) && - !test_and_clear_bit(AFS_VNODE_WRITELOCKED, &vnode->flags)) - BUG(); - if (test_and_set_bit(AFS_VNODE_UNLOCKING, &vnode->flags)) - BUG(); - vnode->unlock_key = key_get(key); + _enter(""); + + if (vnode->lock_state == AFS_VNODE_LOCK_GRANTED || + vnode->lock_state == AFS_VNODE_LOCK_EXTENDING) { + cancel_delayed_work(&vnode->lock_work); + + vnode->lock_state = AFS_VNODE_LOCK_NEED_UNLOCK; + afs_lock_may_be_available(vnode); + } +} + +/* + * Check that our view of the file metadata is up to date and check to see + * whether we think that we have a locking permit. + */ +static int afs_do_setlk_check(struct afs_vnode *vnode, struct key *key, + afs_lock_type_t type, bool can_sleep) +{ + afs_access_t access; + int ret; + + /* Make sure we've got a callback on this file and that our view of the + * data version is up to date. + */ + ret = afs_validate(vnode, key); + if (ret < 0) + return ret; + + /* Check the permission set to see if we're actually going to be + * allowed to get a lock on this file. + */ + ret = afs_check_permit(vnode, key, &access); + if (ret < 0) + return ret; + + /* At a rough estimation, you need LOCK, WRITE or INSERT perm to + * read-lock a file and WRITE or INSERT perm to write-lock a file. + * + * We can't rely on the server to do this for us since if we want to + * share a read lock that we already have, we won't go the server. + */ + if (type == AFS_LOCK_READ) { + if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE | AFS_ACE_LOCK))) + return -EACCES; + if (vnode->status.lock_count == -1 && !can_sleep) + return -EAGAIN; /* Write locked */ + } else { + if (!(access & (AFS_ACE_INSERT | AFS_ACE_WRITE))) + return -EACCES; + if (vnode->status.lock_count != 0 && !can_sleep) + return -EAGAIN; /* Locked */ + } + + return 0; +} + +/* + * Remove the front runner from the pending queue. + * - The caller must hold vnode->lock. + */ +static void afs_dequeue_lock(struct afs_vnode *vnode, struct file_lock *fl) +{ + struct file_lock *next; + + _enter(""); + + /* ->lock_type, ->lock_key and ->lock_state only belong to this + * file_lock if we're at the front of the pending queue or if we have + * the lock granted or if the lock_state is NEED_UNLOCK or UNLOCKING. + */ + if (vnode->granted_locks.next == &fl->fl_u.afs.link && + vnode->granted_locks.prev == &fl->fl_u.afs.link) { + list_del_init(&fl->fl_u.afs.link); + afs_defer_unlock(vnode); + return; + } + + if (!list_empty(&vnode->granted_locks) || + vnode->pending_locks.next != &fl->fl_u.afs.link) { + list_del_init(&fl->fl_u.afs.link); + return; + } + + list_del_init(&fl->fl_u.afs.link); + key_put(vnode->lock_key); + vnode->lock_key = NULL; + vnode->lock_state = AFS_VNODE_LOCK_NONE; + + if (list_empty(&vnode->pending_locks)) + return; + + /* The new front of the queue now owns the state variables. */ + next = list_entry(vnode->pending_locks.next, + struct file_lock, fl_u.afs.link); + vnode->lock_key = afs_file_key(next->fl_file); + vnode->lock_type = (next->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; + vnode->lock_state = AFS_VNODE_LOCK_WAITING_FOR_CB; afs_lock_may_be_available(vnode); } @@ -315,7 +424,7 @@ static void afs_defer_unlock(struct afs_vnode *vnode, struct key *key) */ static int afs_do_setlk(struct file *file, struct file_lock *fl) { - struct inode *inode = file_inode(file); + struct inode *inode = locks_inode(file); struct afs_vnode *vnode = AFS_FS_I(inode); afs_lock_type_t type; struct key *key = afs_file_key(file); @@ -333,165 +442,136 @@ static int afs_do_setlk(struct file *file, struct file_lock *fl) type = (fl->fl_type == F_RDLCK) ? AFS_LOCK_READ : AFS_LOCK_WRITE; - spin_lock(&inode->i_lock); - - /* make sure we've got a callback on this file and that our view of the - * data version is up to date */ - ret = afs_validate(vnode, key); + ret = afs_do_setlk_check(vnode, key, type, fl->fl_flags & FL_SLEEP); if (ret < 0) - goto error; - - if (vnode->status.lock_count != 0 && !(fl->fl_flags & FL_SLEEP)) { - ret = -EAGAIN; - goto error; - } + return ret; spin_lock(&vnode->lock); - /* if we've already got a readlock on the server then we can instantly + /* If we've already got a readlock on the server then we instantly * grant another readlock, irrespective of whether there are any - * pending writelocks */ + * pending writelocks. + */ if (type == AFS_LOCK_READ && - vnode->flags & (1 << AFS_VNODE_READLOCKED)) { + vnode->lock_state == AFS_VNODE_LOCK_GRANTED && + vnode->lock_type == AFS_LOCK_READ) { _debug("instant readlock"); - ASSERTCMP(vnode->flags & - ((1 << AFS_VNODE_LOCKING) | - (1 << AFS_VNODE_WRITELOCKED)), ==, 0); ASSERT(!list_empty(&vnode->granted_locks)); - goto sharing_existing_lock; + goto share_existing_lock; } - /* if there's no-one else with a lock on this vnode, then we need to - * ask the server for a lock */ - if (list_empty(&vnode->pending_locks) && - list_empty(&vnode->granted_locks)) { - _debug("not locked"); - ASSERTCMP(vnode->flags & - ((1 << AFS_VNODE_LOCKING) | - (1 << AFS_VNODE_READLOCKED) | - (1 << AFS_VNODE_WRITELOCKED)), ==, 0); - list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks); - set_bit(AFS_VNODE_LOCKING, &vnode->flags); - spin_unlock(&vnode->lock); - - ret = afs_set_lock(vnode, key, type); - clear_bit(AFS_VNODE_LOCKING, &vnode->flags); - switch (ret) { - case 0: - _debug("acquired"); - goto acquired_server_lock; - case -EWOULDBLOCK: - _debug("would block"); - spin_lock(&vnode->lock); - ASSERT(list_empty(&vnode->granted_locks)); - ASSERTCMP(vnode->pending_locks.next, ==, - &fl->fl_u.afs.link); - goto wait; - default: - spin_lock(&vnode->lock); - list_del_init(&fl->fl_u.afs.link); - spin_unlock(&vnode->lock); - goto error; - } - } - - /* otherwise, we need to wait for a local lock to become available */ - _debug("wait local"); list_add_tail(&fl->fl_u.afs.link, &vnode->pending_locks); -wait: - if (!(fl->fl_flags & FL_SLEEP)) { - _debug("noblock"); - ret = -EAGAIN; - goto abort_attempt; - } + + if (vnode->lock_state != AFS_VNODE_LOCK_NONE) + goto need_to_wait; + + /* We don't have a lock on this vnode and we aren't currently waiting + * for one either, so ask the server for a lock. + * + * Note that we need to be careful if we get interrupted by a signal + * after dispatching the request as we may still get the lock, even + * though we don't wait for the reply (it's not too bad a problem - the + * lock will expire in 10 mins anyway). + */ + _debug("not locked"); + vnode->lock_key = key_get(key); + vnode->lock_type = type; + vnode->lock_state = AFS_VNODE_LOCK_SETTING; spin_unlock(&vnode->lock); - /* now we need to sleep and wait for the lock manager thread to get the - * lock from the server */ - _debug("sleep"); - ret = wait_event_interruptible(fl->fl_wait, - fl->fl_u.afs.state <= AFS_LOCK_GRANTED); - if (fl->fl_u.afs.state <= AFS_LOCK_GRANTED) { - ret = fl->fl_u.afs.state; - if (ret < 0) - goto error; - spin_lock(&vnode->lock); - goto given_lock; - } - - /* we were interrupted, but someone may still be in the throes of - * giving us the lock */ - _debug("intr"); - ASSERTCMP(ret, ==, -ERESTARTSYS); + ret = afs_set_lock(vnode, key, type); /* RPC */ spin_lock(&vnode->lock); - if (fl->fl_u.afs.state <= AFS_LOCK_GRANTED) { - ret = fl->fl_u.afs.state; - if (ret < 0) { - spin_unlock(&vnode->lock); - goto error; - } - goto given_lock; + switch (ret) { + default: + goto abort_attempt; + + case -EWOULDBLOCK: + /* The server doesn't have a lock-waiting queue, so the client + * will have to retry. The server will break the outstanding + * callbacks on a file when a lock is released. + */ + _debug("would block"); + ASSERT(list_empty(&vnode->granted_locks)); + ASSERTCMP(vnode->pending_locks.next, ==, &fl->fl_u.afs.link); + vnode->lock_state = AFS_VNODE_LOCK_WAITING_FOR_CB; + goto need_to_wait; + + case 0: + _debug("acquired"); + break; } + /* we've acquired a server lock, but it needs to be renewed after 5 + * mins */ + vnode->lock_state = AFS_VNODE_LOCK_GRANTED; + afs_schedule_lock_extension(vnode); + +share_existing_lock: + /* the lock has been granted as far as we're concerned... */ + fl->fl_u.afs.state = AFS_LOCK_GRANTED; + list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks); + +given_lock: + /* ... but we do still need to get the VFS's blessing */ + spin_unlock(&vnode->lock); + + ret = posix_lock_file(file, fl, NULL); + if (ret < 0) + goto vfs_rejected_lock; + + /* Again, make sure we've got a callback on this file and, again, make + * sure that our view of the data version is up to date (we ignore + * errors incurred here and deal with the consequences elsewhere). + */ + afs_validate(vnode, key); + _leave(" = 0"); + return 0; + +need_to_wait: + /* We're going to have to wait. Either this client doesn't have a lock + * on the server yet and we need to wait for a callback to occur, or + * the client does have a lock on the server, but it belongs to some + * other process(es) and is incompatible with the lock we want. + */ + ret = -EAGAIN; + if (fl->fl_flags & FL_SLEEP) { + spin_unlock(&vnode->lock); + + _debug("sleep"); + ret = wait_event_interruptible(fl->fl_wait, + fl->fl_u.afs.state != AFS_LOCK_PENDING); + + spin_lock(&vnode->lock); + } + + if (fl->fl_u.afs.state == AFS_LOCK_GRANTED) + goto given_lock; + if (fl->fl_u.afs.state < 0) + ret = fl->fl_u.afs.state; + abort_attempt: /* we aren't going to get the lock, either because we're unwilling to * wait, or because some signal happened */ _debug("abort"); - if (list_empty(&vnode->granted_locks) && - vnode->pending_locks.next == &fl->fl_u.afs.link) { - if (vnode->pending_locks.prev != &fl->fl_u.afs.link) { - /* kick the next pending lock into having a go */ - list_del_init(&fl->fl_u.afs.link); - afs_lock_may_be_available(vnode); - } - } else { - list_del_init(&fl->fl_u.afs.link); - } + afs_dequeue_lock(vnode, fl); + +error_unlock: spin_unlock(&vnode->lock); - goto error; - -acquired_server_lock: - /* we've acquired a server lock, but it needs to be renewed after 5 - * mins */ - spin_lock(&vnode->lock); - afs_schedule_lock_extension(vnode); - if (type == AFS_LOCK_READ) - set_bit(AFS_VNODE_READLOCKED, &vnode->flags); - else - set_bit(AFS_VNODE_WRITELOCKED, &vnode->flags); -sharing_existing_lock: - /* the lock has been granted as far as we're concerned... */ - fl->fl_u.afs.state = AFS_LOCK_GRANTED; - list_move_tail(&fl->fl_u.afs.link, &vnode->granted_locks); -given_lock: - /* ... but we do still need to get the VFS's blessing */ - ASSERT(!(vnode->flags & (1 << AFS_VNODE_LOCKING))); - ASSERT((vnode->flags & ((1 << AFS_VNODE_READLOCKED) | - (1 << AFS_VNODE_WRITELOCKED))) != 0); - ret = posix_lock_file(file, fl, NULL); - if (ret < 0) - goto vfs_rejected_lock; - spin_unlock(&vnode->lock); - - /* again, make sure we've got a callback on this file and, again, make - * sure that our view of the data version is up to date (we ignore - * errors incurred here and deal with the consequences elsewhere) */ - afs_validate(vnode, key); - -error: - spin_unlock(&inode->i_lock); _leave(" = %d", ret); return ret; vfs_rejected_lock: - /* the VFS rejected the lock we just obtained, so we have to discard - * what we just got */ + /* The VFS rejected the lock we just obtained, so we have to discard + * what we just got. We defer this to the lock manager work item to + * deal with. + */ _debug("vfs refused %d", ret); + spin_lock(&vnode->lock); list_del_init(&fl->fl_u.afs.link); if (list_empty(&vnode->granted_locks)) - afs_defer_unlock(vnode, key); - goto abort_attempt; + afs_defer_unlock(vnode); + goto error_unlock; } /* @@ -499,34 +579,21 @@ vfs_rejected_lock: */ static int afs_do_unlk(struct file *file, struct file_lock *fl) { - struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host); - struct key *key = afs_file_key(file); + struct afs_vnode *vnode = AFS_FS_I(locks_inode(file)); int ret; _enter("{%x:%u},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type); + /* Flush all pending writes before doing anything with locks. */ + vfs_fsync(file, 0); + /* only whole-file unlocks are supported */ if (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX) return -EINVAL; - fl->fl_ops = &afs_lock_ops; - INIT_LIST_HEAD(&fl->fl_u.afs.link); - fl->fl_u.afs.state = AFS_LOCK_PENDING; - - spin_lock(&vnode->lock); ret = posix_lock_file(file, fl, NULL); - if (ret < 0) { - spin_unlock(&vnode->lock); - _leave(" = %d [vfs]", ret); - return ret; - } - - /* discard the server lock only if all granted locks are gone */ - if (list_empty(&vnode->granted_locks)) - afs_defer_unlock(vnode, key); - spin_unlock(&vnode->lock); - _leave(" = 0"); - return 0; + _leave(" = %d [%u]", ret, vnode->lock_state); + return ret; } /* @@ -534,7 +601,7 @@ static int afs_do_unlk(struct file *file, struct file_lock *fl) */ static int afs_do_getlk(struct file *file, struct file_lock *fl) { - struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host); + struct afs_vnode *vnode = AFS_FS_I(locks_inode(file)); struct key *key = afs_file_key(file); int ret, lock_count; @@ -542,29 +609,25 @@ static int afs_do_getlk(struct file *file, struct file_lock *fl) fl->fl_type = F_UNLCK; - inode_lock(&vnode->vfs_inode); - /* check local lock records first */ - ret = 0; posix_test_lock(file, fl); if (fl->fl_type == F_UNLCK) { /* no local locks; consult the server */ ret = afs_fetch_status(vnode, key); if (ret < 0) goto error; - lock_count = vnode->status.lock_count; - if (lock_count) { - if (lock_count > 0) - fl->fl_type = F_RDLCK; - else - fl->fl_type = F_WRLCK; - fl->fl_start = 0; - fl->fl_end = OFFSET_MAX; - } + + lock_count = READ_ONCE(vnode->status.lock_count); + if (lock_count > 0) + fl->fl_type = F_RDLCK; + else + fl->fl_type = F_WRLCK; + fl->fl_start = 0; + fl->fl_end = OFFSET_MAX; } + ret = 0; error: - inode_unlock(&vnode->vfs_inode); _leave(" = %d [%hd]", ret, fl->fl_type); return ret; } @@ -574,7 +637,7 @@ error: */ int afs_lock(struct file *file, int cmd, struct file_lock *fl) { - struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); + struct afs_vnode *vnode = AFS_FS_I(locks_inode(file)); _enter("{%x:%u},%d,{t=%x,fl=%x,r=%Ld:%Ld}", vnode->fid.vid, vnode->fid.vnode, cmd, @@ -597,7 +660,7 @@ int afs_lock(struct file *file, int cmd, struct file_lock *fl) */ int afs_flock(struct file *file, int cmd, struct file_lock *fl) { - struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); + struct afs_vnode *vnode = AFS_FS_I(locks_inode(file)); _enter("{%x:%u},%d,{t=%x,fl=%x}", vnode->fid.vid, vnode->fid.vnode, cmd, @@ -627,9 +690,13 @@ int afs_flock(struct file *file, int cmd, struct file_lock *fl) */ static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl) { + struct afs_vnode *vnode = AFS_FS_I(locks_inode(fl->fl_file)); + _enter(""); + spin_lock(&vnode->lock); list_add(&new->fl_u.afs.link, &fl->fl_u.afs.link); + spin_unlock(&vnode->lock); } /* @@ -638,7 +705,12 @@ static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl) */ static void afs_fl_release_private(struct file_lock *fl) { + struct afs_vnode *vnode = AFS_FS_I(locks_inode(fl->fl_file)); + _enter(""); - list_del_init(&fl->fl_u.afs.link); + spin_lock(&vnode->lock); + afs_dequeue_lock(vnode, fl); + _debug("state %u for %p", vnode->lock_state, vnode); + spin_unlock(&vnode->lock); } diff --git a/fs/afs/internal.h b/fs/afs/internal.h index bd8dcee7e066..e03910cebdd4 100644 --- a/fs/afs/internal.h +++ b/fs/afs/internal.h @@ -430,6 +430,16 @@ struct afs_volume { u8 name[AFS_MAXVOLNAME + 1]; /* NUL-padded volume name */ }; +enum afs_lock_state { + AFS_VNODE_LOCK_NONE, /* The vnode has no lock on the server */ + AFS_VNODE_LOCK_WAITING_FOR_CB, /* We're waiting for the server to break the callback */ + AFS_VNODE_LOCK_SETTING, /* We're asking the server for a lock */ + AFS_VNODE_LOCK_GRANTED, /* We have a lock on the server */ + AFS_VNODE_LOCK_EXTENDING, /* We're extending a lock on the server */ + AFS_VNODE_LOCK_NEED_UNLOCK, /* We need to unlock on the server */ + AFS_VNODE_LOCK_UNLOCKING, /* We're telling the server to unlock */ +}; + /* * AFS inode private data */ @@ -454,18 +464,16 @@ struct afs_vnode { #define AFS_VNODE_ZAP_DATA 3 /* set if vnode's data should be invalidated */ #define AFS_VNODE_DELETED 4 /* set if vnode deleted on server */ #define AFS_VNODE_MOUNTPOINT 5 /* set if vnode is a mountpoint symlink */ -#define AFS_VNODE_LOCKING 6 /* set if waiting for lock on vnode */ -#define AFS_VNODE_READLOCKED 7 /* set if vnode is read-locked on the server */ -#define AFS_VNODE_WRITELOCKED 8 /* set if vnode is write-locked on the server */ -#define AFS_VNODE_UNLOCKING 9 /* set if vnode is being unlocked on the server */ -#define AFS_VNODE_AUTOCELL 10 /* set if Vnode is an auto mount point */ -#define AFS_VNODE_PSEUDODIR 11 /* set if Vnode is a pseudo directory */ +#define AFS_VNODE_AUTOCELL 6 /* set if Vnode is an auto mount point */ +#define AFS_VNODE_PSEUDODIR 7 /* set if Vnode is a pseudo directory */ struct list_head wb_keys; /* List of keys available for writeback */ struct list_head pending_locks; /* locks waiting to be granted */ struct list_head granted_locks; /* locks granted on this file */ struct delayed_work lock_work; /* work to be done in locking */ - struct key *unlock_key; /* key to be used in unlocking */ + struct key *lock_key; /* Key to be used in lock ops */ + enum afs_lock_state lock_state : 8; + afs_lock_type_t lock_type : 8; /* outstanding callback notification on this file */ struct afs_cb_interest *cb_interest; /* Server on which this resides */ @@ -843,6 +851,7 @@ extern void afs_clear_permits(struct afs_vnode *); extern void afs_cache_permit(struct afs_vnode *, struct key *, unsigned int); extern void afs_zap_permits(struct rcu_head *); extern struct key *afs_request_key(struct afs_cell *); +extern int afs_check_permit(struct afs_vnode *, struct key *, afs_access_t *); extern int afs_permission(struct inode *, int); extern void __exit afs_clean_up_permit_cache(void); diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c index e728ca1776c9..d04511fb3879 100644 --- a/fs/afs/rotate.c +++ b/fs/afs/rotate.c @@ -46,8 +46,7 @@ bool afs_begin_vnode_operation(struct afs_fs_cursor *fc, struct afs_vnode *vnode return false; } - if (test_bit(AFS_VNODE_READLOCKED, &vnode->flags) || - test_bit(AFS_VNODE_WRITELOCKED, &vnode->flags)) + if (vnode->lock_state != AFS_VNODE_LOCK_NONE) fc->flags |= AFS_FS_CURSOR_CUR_ONLY; return true; } @@ -117,7 +116,7 @@ static void afs_busy(struct afs_volume *volume, u32 abort_code) case VSALVAGING: m = "being salvaged"; break; default: m = "busy"; break; } - + pr_notice("kAFS: Volume %u '%s' is %s\n", volume->vid, volume->name, m); } @@ -438,24 +437,67 @@ bool afs_select_current_fileserver(struct afs_fs_cursor *fc) _enter(""); - if (!cbi) { - fc->ac.error = -ESTALE; + switch (fc->ac.error) { + case SHRT_MAX: + if (!cbi) { + fc->ac.error = -ESTALE; + fc->flags |= AFS_FS_CURSOR_STOP; + return false; + } + + fc->cbi = afs_get_cb_interest(vnode->cb_interest); + + read_lock(&cbi->server->fs_lock); + alist = rcu_dereference_protected(cbi->server->addresses, + lockdep_is_held(&cbi->server->fs_lock)); + afs_get_addrlist(alist); + read_unlock(&cbi->server->fs_lock); + if (!alist) { + fc->ac.error = -ESTALE; + fc->flags |= AFS_FS_CURSOR_STOP; + return false; + } + + fc->ac.alist = alist; + fc->ac.addr = NULL; + fc->ac.start = READ_ONCE(alist->index); + fc->ac.index = fc->ac.start; + fc->ac.error = 0; + fc->ac.begun = false; + goto iterate_address; + + case 0: + default: + /* Success or local failure. Stop. */ fc->flags |= AFS_FS_CURSOR_STOP; + _leave(" = f [okay/local %d]", fc->ac.error); return false; + + case -ECONNABORTED: + fc->flags |= AFS_FS_CURSOR_STOP; + _leave(" = f [abort]"); + return false; + + case -ENETUNREACH: + case -EHOSTUNREACH: + case -ECONNREFUSED: + case -ETIMEDOUT: + case -ETIME: + _debug("no conn"); + goto iterate_address; } - read_lock(&cbi->server->fs_lock); - alist = afs_get_addrlist(cbi->server->addresses); - read_unlock(&cbi->server->fs_lock); - if (!alist) { - fc->ac.error = -ESTALE; - fc->flags |= AFS_FS_CURSOR_STOP; - return false; +iterate_address: + /* Iterate over the current server's address list to try and find an + * address on which it will respond to us. + */ + if (afs_iterate_addresses(&fc->ac)) { + _leave(" = t"); + return true; } - fc->ac.alist = alist; - fc->ac.error = 0; - return true; + afs_end_cursor(&fc->ac); + return false; } /* diff --git a/fs/afs/security.c b/fs/afs/security.c index 46a881a4d08f..2b00097101b3 100644 --- a/fs/afs/security.c +++ b/fs/afs/security.c @@ -284,8 +284,8 @@ someone_else_changed_it: * permitted to be accessed with this authorisation, and if so, what access it * is granted */ -static int afs_check_permit(struct afs_vnode *vnode, struct key *key, - afs_access_t *_access) +int afs_check_permit(struct afs_vnode *vnode, struct key *key, + afs_access_t *_access) { struct afs_permits *permits; bool valid = false; diff --git a/fs/afs/server_list.c b/fs/afs/server_list.c index 26bad7032bba..0ab3f8457839 100644 --- a/fs/afs/server_list.c +++ b/fs/afs/server_list.c @@ -17,7 +17,7 @@ void afs_put_serverlist(struct afs_net *net, struct afs_server_list *slist) { int i; - if (refcount_dec_and_test(&slist->usage)) { + if (slist && refcount_dec_and_test(&slist->usage)) { for (i = 0; i < slist->nr_servers; i++) { afs_put_cb_interest(net, slist->servers[i].cb_interest); afs_put_server(net, slist->servers[i].server); diff --git a/fs/afs/write.c b/fs/afs/write.c index 18e46e31523c..cb5f8a3df577 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -119,6 +119,11 @@ try_again: } if (f != t) { + if (PageWriteback(page)) { + trace_afs_page_dirty(vnode, tracepoint_string("alrdy"), + page->index, priv); + goto flush_conflicting_write; + } if (to < f || from > t) goto flush_conflicting_write; if (from < f)