[PATCH 4/5] ipc: simplify ipc initialization

From: Davidlohr Bueso
Date: Fri Jun 01 2018 - 12:02:27 EST


Now that we know that rhashtable_init() will not fail, we
can get rid of a lot of the unnecessary cleanup paths when
the call errored out.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
ipc/msg.c | 9 ++++-----
ipc/namespace.c | 20 ++++----------------
ipc/sem.c | 10 ++++------
ipc/shm.c | 9 ++++-----
ipc/util.c | 18 +++++-------------
ipc/util.h | 18 +++++++++---------
6 files changed, 30 insertions(+), 54 deletions(-)

diff --git a/ipc/msg.c b/ipc/msg.c
index 3b6545302598..62545ce19173 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -1228,7 +1228,7 @@ COMPAT_SYSCALL_DEFINE5(msgrcv, int, msqid, compat_uptr_t, msgp,
}
#endif

-int msg_init_ns(struct ipc_namespace *ns)
+void msg_init_ns(struct ipc_namespace *ns)
{
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
@@ -1236,7 +1236,7 @@ int msg_init_ns(struct ipc_namespace *ns)

atomic_set(&ns->msg_bytes, 0);
atomic_set(&ns->msg_hdrs, 0);
- return ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
+ ipc_init_ids(&ns->ids[IPC_MSG_IDS]);
}

#ifdef CONFIG_IPC_NS
@@ -1277,12 +1277,11 @@ static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
}
#endif

-int __init msg_init(void)
+void __init msg_init(void)
{
- const int err = msg_init_ns(&init_ipc_ns);
+ msg_init_ns(&init_ipc_ns);

ipc_init_proc_interface("sysvipc/msg",
" key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n",
IPC_MSG_IDS, sysvipc_msg_proc_show);
- return err;
}
diff --git a/ipc/namespace.c b/ipc/namespace.c
index f59a89966f92..21607791d62c 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -55,28 +55,16 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns,
ns->user_ns = get_user_ns(user_ns);
ns->ucounts = ucounts;

- err = sem_init_ns(ns);
+ err = mq_init_ns(ns);
if (err)
goto fail_put;
- err = msg_init_ns(ns);
- if (err)
- goto fail_destroy_sem;
- err = shm_init_ns(ns);
- if (err)
- goto fail_destroy_msg;

- err = mq_init_ns(ns);
- if (err)
- goto fail_destroy_shm;
+ sem_init_ns(ns);
+ msg_init_ns(ns);
+ shm_init_ns(ns);

return ns;

-fail_destroy_shm:
- shm_exit_ns(ns);
-fail_destroy_msg:
- msg_exit_ns(ns);
-fail_destroy_sem:
- sem_exit_ns(ns);
fail_put:
put_user_ns(ns->user_ns);
ns_free_inum(&ns->ns);
diff --git a/ipc/sem.c b/ipc/sem.c
index 20f649eed8c6..78ea913ee0d8 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -220,14 +220,14 @@ static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#define sc_semopm sem_ctls[2]
#define sc_semmni sem_ctls[3]

-int sem_init_ns(struct ipc_namespace *ns)
+void sem_init_ns(struct ipc_namespace *ns)
{
ns->sc_semmsl = SEMMSL;
ns->sc_semmns = SEMMNS;
ns->sc_semopm = SEMOPM;
ns->sc_semmni = SEMMNI;
ns->used_sems = 0;
- return ipc_init_ids(&ns->ids[IPC_SEM_IDS]);
+ ipc_init_ids(&ns->ids[IPC_SEM_IDS]);
}

#ifdef CONFIG_IPC_NS
@@ -239,14 +239,12 @@ void sem_exit_ns(struct ipc_namespace *ns)
}
#endif

-int __init sem_init(void)
+void __init sem_init(void)
{
- const int err = sem_init_ns(&init_ipc_ns);
-
+ sem_init_ns(&init_ipc_ns);
ipc_init_proc_interface("sysvipc/sem",
" key semid perms nsems uid gid cuid cgid otime ctime\n",
IPC_SEM_IDS, sysvipc_sem_proc_show);
- return err;
}

/**
diff --git a/ipc/shm.c b/ipc/shm.c
index 051a3e1fb8df..e602a6fc3991 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -95,14 +95,14 @@ static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp);
static int sysvipc_shm_proc_show(struct seq_file *s, void *it);
#endif

-int shm_init_ns(struct ipc_namespace *ns)
+void shm_init_ns(struct ipc_namespace *ns)
{
ns->shm_ctlmax = SHMMAX;
ns->shm_ctlall = SHMALL;
ns->shm_ctlmni = SHMMNI;
ns->shm_rmid_forced = 0;
ns->shm_tot = 0;
- return ipc_init_ids(&shm_ids(ns));
+ ipc_init_ids(&shm_ids(ns));
}

/*
@@ -135,9 +135,8 @@ void shm_exit_ns(struct ipc_namespace *ns)

static int __init ipc_ns_init(void)
{
- const int err = shm_init_ns(&init_ipc_ns);
- WARN(err, "ipc: sysv shm_init_ns failed: %d\n", err);
- return err;
+ shm_init_ns(&init_ipc_ns);
+ return 0;
}

pure_initcall(ipc_ns_init);
diff --git a/ipc/util.c b/ipc/util.c
index 823e09e72c58..06d7c575847c 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -87,16 +87,12 @@ struct ipc_proc_iface {
*/
static int __init ipc_init(void)
{
- int err_sem, err_msg;
-
proc_mkdir("sysvipc", NULL);
- err_sem = sem_init();
- WARN(err_sem, "ipc: sysv sem_init failed: %d\n", err_sem);
- err_msg = msg_init();
- WARN(err_msg, "ipc: sysv msg_init failed: %d\n", err_msg);
+ sem_init();
+ msg_init();
shm_init();

- return err_msg ? err_msg : err_sem;
+ return 0;
}
device_initcall(ipc_init);

@@ -115,21 +111,17 @@ static const struct rhashtable_params ipc_kht_params = {
* Set up the sequence range to use for the ipc identifier range (limited
* below IPCMNI) then initialise the keys hashtable and ids idr.
*/
-int ipc_init_ids(struct ipc_ids *ids)
+void ipc_init_ids(struct ipc_ids *ids)
{
- int err;
ids->in_use = 0;
ids->seq = 0;
init_rwsem(&ids->rwsem);
- err = rhashtable_init(&ids->key_ht, &ipc_kht_params);
- if (err)
- return err;
+ rhashtable_init(&ids->key_ht, &ipc_kht_params);
idr_init(&ids->ipcs_idr);
ids->max_id = -1;
#ifdef CONFIG_CHECKPOINT_RESTORE
ids->next_id = -1;
#endif
- return 0;
}

#ifdef CONFIG_PROC_FS
diff --git a/ipc/util.h b/ipc/util.h
index 0aba3230d007..65fad8a94da8 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -18,8 +18,8 @@
#define IPCMNI 32768 /* <= MAX_INT limit for ipc arrays (including sysctl changes) */
#define SEQ_MULTIPLIER (IPCMNI)

-int sem_init(void);
-int msg_init(void);
+void sem_init(void);
+void msg_init(void);
void shm_init(void);

struct ipc_namespace;
@@ -34,17 +34,17 @@ static inline void mq_put_mnt(struct ipc_namespace *ns) { }
#endif

#ifdef CONFIG_SYSVIPC
-int sem_init_ns(struct ipc_namespace *ns);
-int msg_init_ns(struct ipc_namespace *ns);
-int shm_init_ns(struct ipc_namespace *ns);
+void sem_init_ns(struct ipc_namespace *ns);
+void msg_init_ns(struct ipc_namespace *ns);
+void shm_init_ns(struct ipc_namespace *ns);

void sem_exit_ns(struct ipc_namespace *ns);
void msg_exit_ns(struct ipc_namespace *ns);
void shm_exit_ns(struct ipc_namespace *ns);
#else
-static inline int sem_init_ns(struct ipc_namespace *ns) { return 0; }
-static inline int msg_init_ns(struct ipc_namespace *ns) { return 0; }
-static inline int shm_init_ns(struct ipc_namespace *ns) { return 0; }
+static inline void sem_init_ns(struct ipc_namespace *ns) { }
+static inline void msg_init_ns(struct ipc_namespace *ns) { }
+static inline void shm_init_ns(struct ipc_namespace *ns) { }

static inline void sem_exit_ns(struct ipc_namespace *ns) { }
static inline void msg_exit_ns(struct ipc_namespace *ns) { }
@@ -83,7 +83,7 @@ struct ipc_ops {
struct seq_file;
struct ipc_ids;

-int ipc_init_ids(struct ipc_ids *);
+void ipc_init_ids(struct ipc_ids *);
#ifdef CONFIG_PROC_FS
void __init ipc_init_proc_interface(const char *path, const char *header,
int ids, int (*show)(struct seq_file *, void *));
--
2.16.3