NFSv4: Clean up the legacy idmapper upcall

Replace the BUG_ON(idmap->idmap_key_cons != NULL) with a
WARN_ON_ONCE(). Then get rid of the ACCESS_ONCE(idmap->idmap_key_cons).

Then add helper functions for starting, finishing and aborting the
legacy upcall.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>
This commit is contained in:
Trond Myklebust 2012-09-27 15:44:19 -04:00
parent 0e24d849c4
commit e9ab41b620

View File

@ -330,7 +330,6 @@ static ssize_t nfs_idmap_get_key(const char *name, size_t namelen,
ret = nfs_idmap_request_key(&key_type_id_resolver_legacy,
name, namelen, type, data,
data_size, idmap);
idmap->idmap_key_cons = NULL;
mutex_unlock(&idmap->idmap_mutex);
}
return ret;
@ -662,6 +661,34 @@ out:
return ret;
}
static bool
nfs_idmap_prepare_pipe_upcall(struct idmap *idmap,
struct key_construction *cons)
{
if (idmap->idmap_key_cons != NULL) {
WARN_ON_ONCE(1);
return false;
}
idmap->idmap_key_cons = cons;
return true;
}
static void
nfs_idmap_complete_pipe_upcall_locked(struct idmap *idmap, int ret)
{
struct key_construction *cons = idmap->idmap_key_cons;
idmap->idmap_key_cons = NULL;
complete_request_key(cons, ret);
}
static void
nfs_idmap_abort_pipe_upcall(struct idmap *idmap, int ret)
{
if (idmap->idmap_key_cons != NULL)
nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
}
static int nfs_idmap_legacy_upcall(struct key_construction *cons,
const char *op,
void *aux)
@ -686,21 +713,17 @@ static int nfs_idmap_legacy_upcall(struct key_construction *cons,
if (ret < 0)
goto out2;
if (idmap->idmap_key_cons != NULL) {
WARN_ON_ONCE(1);
ret = -EAGAIN;
ret = -EAGAIN;
if (!nfs_idmap_prepare_pipe_upcall(idmap, cons))
goto out2;
}
idmap->idmap_key_cons = cons;
ret = rpc_queue_upcall(idmap->idmap_pipe, msg);
if (ret < 0)
goto out3;
if (ret < 0) {
nfs_idmap_abort_pipe_upcall(idmap, ret);
kfree(data);
}
return ret;
out3:
idmap->idmap_key_cons = NULL;
out2:
kfree(data);
out1:
@ -741,14 +764,15 @@ idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
struct key_construction *cons;
struct idmap_msg im;
size_t namelen_in;
int ret;
int ret = -ENOKEY;
/* If instantiation is successful, anyone waiting for key construction
* will have been woken up and someone else may now have used
* idmap_key_cons - so after this point we may no longer touch it.
*/
cons = idmap->idmap_key_cons;
idmap->idmap_key_cons = NULL;
if (cons == NULL)
goto out_noupcall;
if (mlen != sizeof(im)) {
ret = -ENOSPC;
@ -778,7 +802,8 @@ idmap_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
}
out:
complete_request_key(cons, ret);
nfs_idmap_complete_pipe_upcall_locked(idmap, ret);
out_noupcall:
return ret;
}
@ -789,12 +814,9 @@ idmap_pipe_destroy_msg(struct rpc_pipe_msg *msg)
struct idmap_legacy_upcalldata,
pipe_msg);
struct idmap *idmap = data->idmap;
struct key_construction *cons;
if (msg->errno) {
cons = idmap->idmap_key_cons;
idmap->idmap_key_cons = NULL;
complete_request_key(cons, msg->errno);
}
if (msg->errno)
nfs_idmap_abort_pipe_upcall(idmap, msg->errno);
/* Free memory allocated in nfs_idmap_legacy_upcall() */
kfree(data);
}
@ -804,7 +826,8 @@ idmap_release_pipe(struct inode *inode)
{
struct rpc_inode *rpci = RPC_I(inode);
struct idmap *idmap = (struct idmap *)rpci->private;
idmap->idmap_key_cons = NULL;
nfs_idmap_abort_pipe_upcall(idmap, -EPIPE);
}
int nfs_map_name_to_uid(const struct nfs_server *server, const char *name, size_t namelen, __u32 *uid)