diff options
Diffstat (limited to 'fs/dlm')
| -rw-r--r-- | fs/dlm/plock.c | 103 |
1 files changed, 90 insertions, 13 deletions
diff --git a/fs/dlm/plock.c b/fs/dlm/plock.c index a8ffa0760913..943d9f8e5564 100644 --- a/fs/dlm/plock.c +++ b/fs/dlm/plock.c @@ -42,6 +42,27 @@ static inline void set_version(struct dlm_plock_info *info) info->version[2] = DLM_PLOCK_VERSION_PATCH; } +static struct plock_op *plock_lookup_waiter(const struct dlm_plock_info *info) +{ + struct plock_op *op = NULL, *iter; + + list_for_each_entry(iter, &recv_list, list) { + if (iter->info.fsid == info->fsid && + iter->info.number == info->number && + iter->info.owner == info->owner && + iter->info.pid == info->pid && + iter->info.start == info->start && + iter->info.end == info->end && + iter->info.ex == info->ex && + iter->info.wait) { + op = iter; + break; + } + } + + return op; +} + static int check_version(struct dlm_plock_info *info) { if ((DLM_PLOCK_VERSION_MAJOR != info->version[0]) || @@ -334,6 +355,74 @@ out: } EXPORT_SYMBOL_GPL(dlm_posix_unlock); +/* + * NOTE: This implementation can only handle async lock requests as nfs + * do it. It cannot handle cancellation of a pending lock request sitting + * in wait_event(), but for now only nfs is the only user local kernel + * user. + */ +int dlm_posix_cancel(dlm_lockspace_t *lockspace, u64 number, struct file *file, + struct file_lock *fl) +{ + struct dlm_plock_info info; + struct plock_op *op; + struct dlm_ls *ls; + int rv; + + /* this only works for async request for now and nfs is the only + * kernel user right now. + */ + if (WARN_ON_ONCE(!fl->fl_lmops || !fl->fl_lmops->lm_grant)) + return -EOPNOTSUPP; + + ls = dlm_find_lockspace_local(lockspace); + if (!ls) + return -EINVAL; + + memset(&info, 0, sizeof(info)); + info.pid = fl->fl_pid; + info.ex = (fl->fl_type == F_WRLCK); + info.fsid = ls->ls_global_id; + dlm_put_lockspace(ls); + info.number = number; + info.start = fl->fl_start; + info.end = fl->fl_end; + info.owner = (__u64)fl->fl_pid; + + rv = do_lock_cancel(&info); + switch (rv) { + case 0: + spin_lock(&ops_lock); + /* lock request to cancel must be on recv_list because + * do_lock_cancel() synchronizes it. + */ + op = plock_lookup_waiter(&info); + if (WARN_ON_ONCE(!op)) { + rv = -ENOLCK; + break; + } + + list_del(&op->list); + spin_unlock(&ops_lock); + WARN_ON(op->info.optype != DLM_PLOCK_OP_LOCK); + op->data->callback(op->data->fl, -EINTR); + dlm_release_plock_op(op); + rv = -EINTR; + break; + case -ENOENT: + /* if cancel wasn't successful we probably were to late + * or it was a non-blocking lock request, so just unlock it. + */ + rv = dlm_posix_unlock(lockspace, number, file, fl); + break; + default: + break; + } + + return rv; +} +EXPORT_SYMBOL_GPL(dlm_posix_cancel); + int dlm_posix_get(dlm_lockspace_t *lockspace, u64 number, struct file *file, struct file_lock *fl) { @@ -457,19 +546,7 @@ static ssize_t dev_write(struct file *file, const char __user *u, size_t count, */ spin_lock(&ops_lock); if (info.wait) { - list_for_each_entry(iter, &recv_list, list) { - if (iter->info.fsid == info.fsid && - iter->info.number == info.number && - iter->info.owner == info.owner && - iter->info.pid == info.pid && - iter->info.start == info.start && - iter->info.end == info.end && - iter->info.ex == info.ex && - iter->info.wait) { - op = iter; - break; - } - } + op = plock_lookup_waiter(&info); } else { list_for_each_entry(iter, &recv_list, list) { if (!iter->info.wait) { |