diff options
Diffstat (limited to 'fs/file_table.c')
| -rw-r--r-- | fs/file_table.c | 189 |
1 files changed, 18 insertions, 171 deletions
diff --git a/fs/file_table.c b/fs/file_table.c index abdd15ad13c..385bfd31512 100644 --- a/fs/file_table.c +++ b/fs/file_table.c @@ -36,8 +36,6 @@ struct files_stat_struct files_stat = { .max_files = NR_FILE }; -DEFINE_STATIC_LGLOCK(files_lglock); - /* SLAB cache for file structures */ static struct kmem_cache *filp_cachep __read_mostly; @@ -54,7 +52,6 @@ static void file_free_rcu(struct rcu_head *head) static inline void file_free(struct file *f) { percpu_counter_dec(&nr_files); - file_check_state(f); call_rcu(&f->f_u.fu_rcuhead, file_free_rcu); } @@ -79,14 +76,14 @@ EXPORT_SYMBOL_GPL(get_max_files); * Handle nr_files sysctl */ #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS) -int proc_nr_files(ctl_table *table, int write, +int proc_nr_files(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { files_stat.nr_files = get_nr_files(); return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); } #else -int proc_nr_files(ctl_table *table, int write, +int proc_nr_files(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { return -ENOSYS; @@ -134,10 +131,10 @@ struct file *get_empty_filp(void) return ERR_PTR(error); } - INIT_LIST_HEAD(&f->f_u.fu_list); atomic_long_set(&f->f_count, 1); rwlock_init(&f->f_owner.lock); spin_lock_init(&f->f_lock); + mutex_init(&f->f_pos_lock); eventpoll_init_file(f); /* f->f_version: 0 */ return f; @@ -178,49 +175,20 @@ struct file *alloc_file(struct path *path, fmode_t mode, file->f_path = *path; file->f_inode = path->dentry->d_inode; file->f_mapping = path->dentry->d_inode->i_mapping; + if ((mode & FMODE_READ) && + likely(fop->read || fop->aio_read || fop->read_iter)) + mode |= FMODE_CAN_READ; + if ((mode & FMODE_WRITE) && + likely(fop->write || fop->aio_write || fop->write_iter)) + mode |= FMODE_CAN_WRITE; file->f_mode = mode; file->f_op = fop; - - /* - * These mounts don't really matter in practice - * for r/o bind mounts. They aren't userspace- - * visible. We do this for consistency, and so - * that we can do debugging checks at __fput() - */ - if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) { - file_take_write(file); - WARN_ON(mnt_clone_write(path->mnt)); - } if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_inc(path->dentry->d_inode); return file; } EXPORT_SYMBOL(alloc_file); -/** - * drop_file_write_access - give up ability to write to a file - * @file: the file to which we will stop writing - * - * This is a central place which will give up the ability - * to write to @file, along with access to write through - * its vfsmount. - */ -static void drop_file_write_access(struct file *file) -{ - struct vfsmount *mnt = file->f_path.mnt; - struct dentry *dentry = file->f_path.dentry; - struct inode *inode = dentry->d_inode; - - put_write_access(inode); - - if (special_file(inode->i_mode)) - return; - if (file_check_writeable(file) != 0) - return; - __mnt_drop_write(mnt); - file_release_write(file); -} - /* the real guts of fput() - releasing the last reference to file */ static void __fput(struct file *file) @@ -237,14 +205,14 @@ static void __fput(struct file *file) * in the file cleanup chain. */ eventpoll_release(file); - locks_remove_flock(file); + locks_remove_file(file); if (unlikely(file->f_flags & FASYNC)) { - if (file->f_op && file->f_op->fasync) + if (file->f_op->fasync) file->f_op->fasync(-1, file, 0); } ima_file_free(file); - if (file->f_op && file->f_op->release) + if (file->f_op->release) file->f_op->release(inode, file); security_file_free(file); if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL && @@ -255,8 +223,10 @@ static void __fput(struct file *file) put_pid(file->f_owner.pid); if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) i_readcount_dec(inode); - if (file->f_mode & FMODE_WRITE) - drop_file_write_access(file); + if (file->f_mode & FMODE_WRITER) { + put_write_access(inode); + __mnt_drop_write(mnt); + } file->f_path.dentry = NULL; file->f_path.mnt = NULL; file->f_inode = NULL; @@ -297,14 +267,13 @@ void flush_delayed_fput(void) delayed_fput(NULL); } -static DECLARE_WORK(delayed_fput_work, delayed_fput); +static DECLARE_DELAYED_WORK(delayed_fput_work, delayed_fput); void fput(struct file *file) { if (atomic_long_dec_and_test(&file->f_count)) { struct task_struct *task = current; - file_sb_list_del(file); if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) { init_task_work(&file->f_u.fu_rcuhead, ____fput); if (!task_work_add(task, &file->f_u.fu_rcuhead, true)) @@ -317,7 +286,7 @@ void fput(struct file *file) } if (llist_add(&file->f_u.fu_llist, &delayed_fput_list)) - schedule_work(&delayed_fput_work); + schedule_delayed_work(&delayed_fput_work, 1); } } @@ -333,7 +302,6 @@ void __fput_sync(struct file *file) { if (atomic_long_dec_and_test(&file->f_count)) { struct task_struct *task = current; - file_sb_list_del(file); BUG_ON(!(task->flags & PF_KTHREAD)); __fput(file); } @@ -345,129 +313,10 @@ void put_filp(struct file *file) { if (atomic_long_dec_and_test(&file->f_count)) { security_file_free(file); - file_sb_list_del(file); file_free(file); } } -static inline int file_list_cpu(struct file *file) -{ -#ifdef CONFIG_SMP - return file->f_sb_list_cpu; -#else - return smp_processor_id(); -#endif -} - -/* helper for file_sb_list_add to reduce ifdefs */ -static inline void __file_sb_list_add(struct file *file, struct super_block *sb) -{ - struct list_head *list; -#ifdef CONFIG_SMP - int cpu; - cpu = smp_processor_id(); - file->f_sb_list_cpu = cpu; - list = per_cpu_ptr(sb->s_files, cpu); -#else - list = &sb->s_files; -#endif - list_add(&file->f_u.fu_list, list); -} - -/** - * file_sb_list_add - add a file to the sb's file list - * @file: file to add - * @sb: sb to add it to - * - * Use this function to associate a file with the superblock of the inode it - * refers to. - */ -void file_sb_list_add(struct file *file, struct super_block *sb) -{ - if (likely(!(file->f_mode & FMODE_WRITE))) - return; - if (!S_ISREG(file_inode(file)->i_mode)) - return; - lg_local_lock(&files_lglock); - __file_sb_list_add(file, sb); - lg_local_unlock(&files_lglock); -} - -/** - * file_sb_list_del - remove a file from the sb's file list - * @file: file to remove - * @sb: sb to remove it from - * - * Use this function to remove a file from its superblock. - */ -void file_sb_list_del(struct file *file) -{ - if (!list_empty(&file->f_u.fu_list)) { - lg_local_lock_cpu(&files_lglock, file_list_cpu(file)); - list_del_init(&file->f_u.fu_list); - lg_local_unlock_cpu(&files_lglock, file_list_cpu(file)); - } -} - -#ifdef CONFIG_SMP - -/* - * These macros iterate all files on all CPUs for a given superblock. - * files_lglock must be held globally. - */ -#define do_file_list_for_each_entry(__sb, __file) \ -{ \ - int i; \ - for_each_possible_cpu(i) { \ - struct list_head *list; \ - list = per_cpu_ptr((__sb)->s_files, i); \ - list_for_each_entry((__file), list, f_u.fu_list) - -#define while_file_list_for_each_entry \ - } \ -} - -#else - -#define do_file_list_for_each_entry(__sb, __file) \ -{ \ - struct list_head *list; \ - list = &(sb)->s_files; \ - list_for_each_entry((__file), list, f_u.fu_list) - -#define while_file_list_for_each_entry \ -} - -#endif - -/** - * mark_files_ro - mark all files read-only - * @sb: superblock in question - * - * All files are marked read-only. We don't care about pending - * delete files so this should be used in 'force' mode only. - */ -void mark_files_ro(struct super_block *sb) -{ - struct file *f; - - lg_global_lock(&files_lglock); - do_file_list_for_each_entry(sb, f) { - if (!file_count(f)) - continue; - if (!(f->f_mode & FMODE_WRITE)) - continue; - spin_lock(&f->f_lock); - f->f_mode &= ~FMODE_WRITE; - spin_unlock(&f->f_lock); - if (file_check_writeable(f) != 0) - continue; - __mnt_drop_write(f->f_path.mnt); - file_release_write(f); - } while_file_list_for_each_entry; - lg_global_unlock(&files_lglock); -} - void __init files_init(unsigned long mempages) { unsigned long n; @@ -482,7 +331,5 @@ void __init files_init(unsigned long mempages) n = (mempages * (PAGE_SIZE / 1024)) / 10; files_stat.max_files = max_t(unsigned long, n, NR_FILE); - files_defer_init(); - lg_lock_init(&files_lglock, "files_lglock"); percpu_counter_init(&nr_files, 0); } |
