diff options
Diffstat (limited to 'fs/dlm')
-rw-r--r-- | fs/dlm/plock.c | 65 |
1 files changed, 61 insertions, 4 deletions
diff --git a/fs/dlm/plock.c b/fs/dlm/plock.c index 30d8b85febbf..e2b878004364 100644 --- a/fs/dlm/plock.c +++ b/fs/dlm/plock.c @@ -71,6 +71,36 @@ static void send_op(struct plock_op *op) wake_up(&send_wq); } +/* If a process was killed while waiting for the only plock on a file, + locks_remove_posix will not see any lock on the file so it won't + send an unlock-close to us to pass on to userspace to clean up the + abandoned waiter. So, we have to insert the unlock-close when the + lock call is interrupted. */ + +static void do_unlock_close(struct dlm_ls *ls, u64 number, + struct file *file, struct file_lock *fl) +{ + struct plock_op *op; + + op = kzalloc(sizeof(*op), GFP_NOFS); + if (!op) + return; + + op->info.optype = DLM_PLOCK_OP_UNLOCK; + op->info.pid = fl->fl_pid; + op->info.fsid = ls->ls_global_id; + op->info.number = number; + op->info.start = 0; + op->info.end = OFFSET_MAX; + if (fl->fl_lmops && fl->fl_lmops->fl_grant) + op->info.owner = (__u64) fl->fl_pid; + else + op->info.owner = (__u64)(long) fl->fl_owner; + + op->info.flags |= DLM_PLOCK_FL_CLOSE; + send_op(op); +} + int dlm_posix_lock(dlm_lockspace_t *lockspace, u64 number, struct file *file, int cmd, struct file_lock *fl) { @@ -114,9 +144,19 @@ int dlm_posix_lock(dlm_lockspace_t *lockspace, u64 number, struct file *file, send_op(op); - if (xop->callback == NULL) - wait_event(recv_wq, (op->done != 0)); - else { + if (xop->callback == NULL) { + rv = wait_event_killable(recv_wq, (op->done != 0)); + if (rv == -ERESTARTSYS) { + log_debug(ls, "dlm_posix_lock: wait killed %llx", + (unsigned long long)number); + spin_lock(&ops_lock); + list_del(&op->list); + spin_unlock(&ops_lock); + kfree(xop); + do_unlock_close(ls, number, file, fl); + goto out; + } + } else { rv = FILE_LOCK_DEFERRED; goto out; } @@ -233,6 +273,13 @@ int dlm_posix_unlock(dlm_lockspace_t *lockspace, u64 number, struct file *file, else op->info.owner = (__u64)(long) fl->fl_owner; + if (fl->fl_flags & FL_CLOSE) { + op->info.flags |= DLM_PLOCK_FL_CLOSE; + send_op(op); + rv = 0; + goto out; + } + send_op(op); wait_event(recv_wq, (op->done != 0)); @@ -334,7 +381,10 @@ static ssize_t dev_read(struct file *file, char __user *u, size_t count, spin_lock(&ops_lock); if (!list_empty(&send_list)) { op = list_entry(send_list.next, struct plock_op, list); - list_move(&op->list, &recv_list); + if (op->info.flags & DLM_PLOCK_FL_CLOSE) + list_del(&op->list); + else + list_move(&op->list, &recv_list); memcpy(&info, &op->info, sizeof(info)); } spin_unlock(&ops_lock); @@ -342,6 +392,13 @@ static ssize_t dev_read(struct file *file, char __user *u, size_t count, if (!op) return -EAGAIN; + /* there is no need to get a reply from userspace for unlocks + that were generated by the vfs cleaning up for a close + (the process did not make an unlock call). */ + + if (op->info.flags & DLM_PLOCK_FL_CLOSE) + kfree(op); + if (copy_to_user(u, &info, sizeof(info))) return -EFAULT; return sizeof(info); |