diff options
Diffstat (limited to 'trans')
| -rw-r--r-- | trans/fakeroot.c | 45 |
1 files changed, 27 insertions, 18 deletions
diff --git a/trans/fakeroot.c b/trans/fakeroot.c index cb4f818d..ad7bec98 100644 --- a/trans/fakeroot.c +++ b/trans/fakeroot.c @@ -108,6 +108,9 @@ new_node (file_t file, mach_port_t idport, int locked, int openmodes, } nn->faked = FAKE_DEFAULT; + /* The light reference allows us to safely keep the node in the + hash table. */ + netfs_nref_light (*np); if (!locked) pthread_mutex_lock (&idport_ihash_lock); err = hurd_ihash_add (&idport_ihash, nn->idport, *np); @@ -155,22 +158,31 @@ set_faked_attribute (struct node *np, unsigned int faked) } } +void +netfs_try_dropping_softrefs (struct node *np) +{ + /* We have to drop our light reference by removing the node from the + idport_ihash hash table. */ + pthread_mutex_lock (&idport_ihash_lock); + + hurd_ihash_locp_remove (&idport_ihash, netfs_node_netnode (np)->idport_locp); + pthread_mutex_unlock (&idport_ihash_lock); + + netfs_nrele_light (np); +} + /* Node NP has no more references; free all its associated storage. */ void netfs_node_norefs (struct node *np) { pthread_mutex_unlock (&np->lock); - pthread_spin_unlock (&netfs_node_refcnt_lock); - pthread_mutex_lock (&idport_ihash_lock); - hurd_ihash_locp_remove (&idport_ihash, netfs_node_netnode (np)->idport_locp); - pthread_mutex_unlock (&idport_ihash_lock); + /* NP was already removed from idport_ihash through + netfs_try_dropping_softrefs. */ mach_port_deallocate (mach_task_self (), netfs_node_netnode (np)->file); mach_port_deallocate (mach_task_self (), netfs_node_netnode (np)->idport); free (np); - - pthread_spin_lock (&netfs_node_refcnt_lock); } /* This is the cleanup function we install in netfs_protid_class. If @@ -363,29 +375,27 @@ netfs_S_dir_lookup (struct protid *diruser, redo_hash_lookup: pthread_mutex_lock (&idport_ihash_lock); pthread_mutex_lock (&dnp->lock); - /* The hashtable may not hold a true reference on the node. Acquire the - refcount lock so that, if a node is found, its reference counter cannot - drop to 0 before we get our own reference. */ - pthread_spin_lock (&netfs_node_refcnt_lock); np = hurd_ihash_find (&idport_ihash, idport); if (np != NULL) { - /* We already know about this node. */ + /* We quickly check that NP has hard references. If the node is being + removed, netfs_try_dropping_softrefs is attempting to drop the light + reference on this. */ + struct references result; + + refcounts_references (&np->refcounts, &result); - if (np->references == 0) + if (result.hard == 0) { - /* But it might be in the process of being released. If so, - unlock the hash table to give the node a chance to actually + /* If so, unlock the hash table to give the node a chance to actually be removed and retry. */ - pthread_spin_unlock (&netfs_node_refcnt_lock); pthread_mutex_unlock (&dnp->lock); pthread_mutex_unlock (&idport_ihash_lock); goto redo_hash_lookup; } /* Otherwise, reference it right away. */ - np->references++; - pthread_spin_unlock (&netfs_node_refcnt_lock); + netfs_nref (np); mach_port_deallocate (mach_task_self (), idport); @@ -405,7 +415,6 @@ netfs_S_dir_lookup (struct protid *diruser, } else { - pthread_spin_unlock (&netfs_node_refcnt_lock); err = new_node (file, idport, 1, flags & (O_RDWR|O_EXEC), &np); pthread_mutex_unlock (&dnp->lock); if (!err) |