diff options
| -rw-r--r-- | include/linux/ipc_namespace.h | 2 | ||||
| -rw-r--r-- | ipc/util.c | 60 | ||||
| -rw-r--r-- | ipc/util.h | 5 |
3 files changed, 47 insertions, 20 deletions
diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h index 474812abe773..d7cf3a850853 100644 --- a/include/linux/ipc_namespace.h +++ b/include/linux/ipc_namespace.h @@ -19,7 +19,9 @@ struct ipc_ids { bool tables_initialized; struct rw_semaphore rwsem; struct idr ipcs_idr; +#ifdef CONFIG_CHECKPOINT_RESTORE int next_id; +#endif struct rhashtable key_ht; }; diff --git a/ipc/util.c b/ipc/util.c index 79b30eee32cd..429c06bdb8ef 100644 --- a/ipc/util.c +++ b/ipc/util.c @@ -116,13 +116,15 @@ int ipc_init_ids(struct ipc_ids *ids) int err; ids->in_use = 0; ids->seq = 0; - ids->next_id = -1; init_rwsem(&ids->rwsem); err = rhashtable_init(&ids->key_ht, &ipc_kht_params); if (err) return err; idr_init(&ids->ipcs_idr); ids->tables_initialized = true; +#ifdef CONFIG_CHECKPOINT_RESTORE + ids->next_id = -1; +#endif return 0; } @@ -216,6 +218,46 @@ int ipc_get_maxid(struct ipc_ids *ids) return max_id; } +#ifdef CONFIG_CHECKPOINT_RESTORE +/* + * Specify desired id for next allocated IPC object. + */ +#define ipc_idr_alloc(ids, new) \ + idr_alloc(&(ids)->ipcs_idr, (new), \ + (ids)->next_id < 0 ? 0 : ipcid_to_idx((ids)->next_id),\ + 0, GFP_NOWAIT) + +static inline int ipc_buildid(int id, struct ipc_ids *ids, + struct kern_ipc_perm *new) +{ + if (ids->next_id < 0) { /* default, behave as !CHECKPOINT_RESTORE */ + new->seq = ids->seq++; + if (ids->seq > IPCID_SEQ_MAX) + ids->seq = 0; + } else { + new->seq = ipcid_to_seqx(ids->next_id); + ids->next_id = -1; + } + + return SEQ_MULTIPLIER * new->seq + id; +} + +#else +#define ipc_idr_alloc(ids, new) \ + idr_alloc(&(ids)->ipcs_idr, (new), 0, 0, GFP_NOWAIT) + +static inline int ipc_buildid(int id, struct ipc_ids *ids, + struct kern_ipc_perm *new) +{ + new->seq = ids->seq++; + if (ids->seq > IPCID_SEQ_MAX) + ids->seq = 0; + + return SEQ_MULTIPLIER * new->seq + id; +} + +#endif /* CONFIG_CHECKPOINT_RESTORE */ + /** * ipc_addid - add an ipc identifier * @ids: ipc identifier set @@ -234,7 +276,6 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size) kuid_t euid; kgid_t egid; int id, err; - int next_id = ids->next_id; if (size > IPCMNI) size = IPCMNI; @@ -254,9 +295,7 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size) new->cuid = new->uid = euid; new->gid = new->cgid = egid; - id = idr_alloc(&ids->ipcs_idr, new, - (next_id < 0) ? 0 : ipcid_to_idx(next_id), 0, - GFP_NOWAIT); + id = ipc_idr_alloc(ids, new); idr_preload_end(); if (id >= 0 && new->key != IPC_PRIVATE) { @@ -274,17 +313,8 @@ int ipc_addid(struct ipc_ids *ids, struct kern_ipc_perm *new, int size) } ids->in_use++; + new->id = ipc_buildid(id, ids, new); - if (next_id < 0) { - new->seq = ids->seq++; - if (ids->seq > IPCID_SEQ_MAX) - ids->seq = 0; - } else { - new->seq = ipcid_to_seqx(next_id); - ids->next_id = -1; - } - - new->id = ipc_buildid(id, new->seq); return id; } diff --git a/ipc/util.h b/ipc/util.h index 579112d90016..0cd6201fe63a 100644 --- a/ipc/util.h +++ b/ipc/util.h @@ -146,11 +146,6 @@ extern struct msg_msg *load_msg(const void __user *src, size_t len); extern struct msg_msg *copy_msg(struct msg_msg *src, struct msg_msg *dst); extern int store_msg(void __user *dest, struct msg_msg *msg, size_t len); -static inline int ipc_buildid(int id, int seq) -{ - return SEQ_MULTIPLIER * seq + id; -} - static inline int ipc_checkid(struct kern_ipc_perm *ipcp, int uid) { return uid / SEQ_MULTIPLIER != ipcp->seq; |