diff options
-rw-r--r-- | fs/aio.c | 27 | ||||
-rw-r--r-- | include/linux/aio.h | 2 | ||||
-rw-r--r-- | include/linux/init_task.h | 1 | ||||
-rw-r--r-- | include/linux/sched.h | 1 | ||||
-rw-r--r-- | kernel/fork.c | 1 |
5 files changed, 10 insertions, 22 deletions
@@ -937,28 +937,19 @@ int fastcall aio_complete(struct kiocb *iocb, long res, long res2) unsigned long tail; int ret; - /* Special case handling for sync iocbs: events go directly - * into the iocb for fast handling. Note that this will not - * work if we allow sync kiocbs to be cancelled. in which - * case the usage count checks will have to move under ctx_lock - * for all cases. + /* + * Special case handling for sync iocbs: + * - events go directly into the iocb for fast handling + * - the sync task with the iocb in its stack holds the single iocb + * ref, no other paths have a way to get another ref + * - the sync task helpfully left a reference to itself in the iocb */ if (is_sync_kiocb(iocb)) { - int ret; - + BUG_ON(iocb->ki_users != 1); iocb->ki_user_data = res; - if (iocb->ki_users == 1) { - iocb->ki_users = 0; - ret = 1; - } else { - spin_lock_irq(&ctx->ctx_lock); - iocb->ki_users--; - ret = (0 == iocb->ki_users); - spin_unlock_irq(&ctx->ctx_lock); - } - /* sync iocbs put the task here for us */ + iocb->ki_users = 0; wake_up_process(iocb->ki_obj.tsk); - return ret; + return 1; } info = &ctx->ring_info; diff --git a/include/linux/aio.h b/include/linux/aio.h index 403d71dcb7c..9e0ae871127 100644 --- a/include/linux/aio.h +++ b/include/linux/aio.h @@ -124,7 +124,7 @@ struct kiocb { (x)->ki_users = 1; \ (x)->ki_key = KIOCB_SYNC_KEY; \ (x)->ki_filp = (filp); \ - (x)->ki_ctx = &tsk->active_mm->default_kioctx; \ + (x)->ki_ctx = NULL; \ (x)->ki_cancel = NULL; \ (x)->ki_dtor = NULL; \ (x)->ki_obj.tsk = tsk; \ diff --git a/include/linux/init_task.h b/include/linux/init_task.h index 68ab5f2ab9c..dcfd2ecccb5 100644 --- a/include/linux/init_task.h +++ b/include/linux/init_task.h @@ -51,7 +51,6 @@ .page_table_lock = SPIN_LOCK_UNLOCKED, \ .mmlist = LIST_HEAD_INIT(name.mmlist), \ .cpu_vm_mask = CPU_MASK_ALL, \ - .default_kioctx = INIT_KIOCTX(name.default_kioctx, name), \ } #define INIT_SIGNALS(sig) { \ diff --git a/include/linux/sched.h b/include/linux/sched.h index 41df8139571..2038bd27b04 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -357,7 +357,6 @@ struct mm_struct { /* aio bits */ rwlock_t ioctx_list_lock; struct kioctx *ioctx_list; - struct kioctx default_kioctx; }; struct sighand_struct { diff --git a/kernel/fork.c b/kernel/fork.c index 2c70c9cdf5d..e0d0b77343f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -323,7 +323,6 @@ static struct mm_struct * mm_init(struct mm_struct * mm) spin_lock_init(&mm->page_table_lock); rwlock_init(&mm->ioctx_list_lock); mm->ioctx_list = NULL; - mm->default_kioctx = (struct kioctx)INIT_KIOCTX(mm->default_kioctx, *mm); mm->free_area_cache = TASK_UNMAPPED_BASE; mm->cached_hole_size = ~0UL; |