diff options
Diffstat (limited to 'fs/file_table.c')
| -rw-r--r-- | fs/file_table.c | 73 |
1 files changed, 51 insertions, 22 deletions
diff --git a/fs/file_table.c b/fs/file_table.c index 5c00dc38558d..c04ed94cdc4b 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -221,7 +221,8 @@ struct file *alloc_empty_file(int flags, const struct cred *cred) /* * Privileged users can go above max_files */ - if (get_nr_files() >= files_stat.max_files && !capable(CAP_SYS_ADMIN)) { + if (unlikely(get_nr_files() >= files_stat.max_files) && + !capable(CAP_SYS_ADMIN)) { /* * percpu_counters are inaccurate. Do an expensive check before * we go and fail. @@ -511,31 +512,37 @@ void flush_delayed_fput(void) } EXPORT_SYMBOL_GPL(flush_delayed_fput); -void fput(struct file *file) +static void __fput_deferred(struct file *file) { - if (file_ref_put(&file->f_ref)) { - struct task_struct *task = current; + struct task_struct *task = current; + + if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) { + file_free(file); + return; + } - if (unlikely(!(file->f_mode & (FMODE_BACKING | FMODE_OPENED)))) { - file_free(file); + if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { + init_task_work(&file->f_task_work, ____fput); + if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) return; - } - if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { - init_task_work(&file->f_task_work, ____fput); - if (!task_work_add(task, &file->f_task_work, TWA_RESUME)) - return; - /* - * After this task has run exit_task_work(), - * task_work_add() will fail. Fall through to delayed - * fput to avoid leaking *file. - */ - } - - if (llist_add(&file->f_llist, &delayed_fput_list)) - schedule_delayed_work(&delayed_fput_work, 1); + /* + * After this task has run exit_task_work(), + * task_work_add() will fail. Fall through to delayed + * fput to avoid leaking *file. + */ } + + if (llist_add(&file->f_llist, &delayed_fput_list)) + schedule_delayed_work(&delayed_fput_work, 1); } +void fput(struct file *file) +{ + if (unlikely(file_ref_put(&file->f_ref))) + __fput_deferred(file); +} +EXPORT_SYMBOL(fput); + /* * synchronous analog of fput(); for kernel threads that might be needed * in some umount() (and thus can't use flush_delayed_fput() without @@ -549,10 +556,32 @@ void __fput_sync(struct file *file) if (file_ref_put(&file->f_ref)) __fput(file); } - -EXPORT_SYMBOL(fput); EXPORT_SYMBOL(__fput_sync); +/* + * Equivalent to __fput_sync(), but optimized for being called with the last + * reference. + * + * See file_ref_put_close() for details. + */ +void fput_close_sync(struct file *file) +{ + if (likely(file_ref_put_close(&file->f_ref))) + __fput(file); +} + +/* + * Equivalent to fput(), but optimized for being called with the last + * reference. + * + * See file_ref_put_close() for details. + */ +void fput_close(struct file *file) +{ + if (file_ref_put_close(&file->f_ref)) + __fput_deferred(file); +} + void __init files_init(void) { struct kmem_cache_args args = { |