diff options
Diffstat (limited to 'ipc/util.c')
-rw-r--r-- | ipc/util.c | 52 |
1 files changed, 1 insertions, 51 deletions
diff --git a/ipc/util.c b/ipc/util.c index 0f468c34e83c..49b3ea615dc5 100644 --- a/ipc/util.c +++ b/ipc/util.c | |||
@@ -716,56 +716,6 @@ struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id) | |||
716 | return out; | 716 | return out; |
717 | } | 717 | } |
718 | 718 | ||
719 | /** | ||
720 | * ipc_lock_down - Lock an ipc structure with rw_sem held | ||
721 | * @ids: IPC identifier set | ||
722 | * @id: ipc id to look for | ||
723 | * | ||
724 | * Look for an id in the ipc ids idr and lock the associated ipc object. | ||
725 | * | ||
726 | * The ipc object is locked on exit. | ||
727 | * | ||
728 | * This is the routine that should be called when the rw_mutex is already | ||
729 | * held, i.e. idr tree protected. | ||
730 | */ | ||
731 | |||
732 | struct kern_ipc_perm *ipc_lock_down(struct ipc_ids *ids, int id) | ||
733 | { | ||
734 | struct kern_ipc_perm *out; | ||
735 | int lid = ipcid_to_idx(id); | ||
736 | |||
737 | rcu_read_lock(); | ||
738 | out = idr_find(&ids->ipcs_idr, lid); | ||
739 | if (out == NULL) { | ||
740 | rcu_read_unlock(); | ||
741 | return ERR_PTR(-EINVAL); | ||
742 | } | ||
743 | |||
744 | spin_lock(&out->lock); | ||
745 | |||
746 | /* | ||
747 | * No need to verify that the structure is still valid since the | ||
748 | * rw_mutex is held. | ||
749 | */ | ||
750 | return out; | ||
751 | } | ||
752 | |||
753 | struct kern_ipc_perm *ipc_lock_check_down(struct ipc_ids *ids, int id) | ||
754 | { | ||
755 | struct kern_ipc_perm *out; | ||
756 | |||
757 | out = ipc_lock_down(ids, id); | ||
758 | if (IS_ERR(out)) | ||
759 | return out; | ||
760 | |||
761 | if (ipc_checkid(out, id)) { | ||
762 | ipc_unlock(out); | ||
763 | return ERR_PTR(-EIDRM); | ||
764 | } | ||
765 | |||
766 | return out; | ||
767 | } | ||
768 | |||
769 | struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id) | 719 | struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id) |
770 | { | 720 | { |
771 | struct kern_ipc_perm *out; | 721 | struct kern_ipc_perm *out; |
@@ -837,7 +787,7 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_ids *ids, int id, int cmd, | |||
837 | int err; | 787 | int err; |
838 | 788 | ||
839 | down_write(&ids->rw_mutex); | 789 | down_write(&ids->rw_mutex); |
840 | ipcp = ipc_lock_check_down(ids, id); | 790 | ipcp = ipc_lock_check(ids, id); |
841 | if (IS_ERR(ipcp)) { | 791 | if (IS_ERR(ipcp)) { |
842 | err = PTR_ERR(ipcp); | 792 | err = PTR_ERR(ipcp); |
843 | goto out_up; | 793 | goto out_up; |