From 1d278a879081ddc40286500e58868aaee47de257 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 5 Jul 2017 16:25:53 +0100 Subject: [PATCH] VFS: Kill off s_options and helpers Kill off s_options, save/replace_mount_options() and generic_show_options() as all filesystems now implement ->show_options() for themselves. This should make it easier to implement a context-based mount where the mount options can be passed individually over a file descriptor. Signed-off-by: David Howells Signed-off-by: Al Viro --- Documentation/filesystems/vfs.txt | 6 ---- fs/efivarfs/super.c | 1 - fs/namespace.c | 59 ------------------------------- fs/super.c | 1 - include/linux/fs.h | 9 ----- 5 files changed, 76 deletions(-) diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index f42b90687d406b..ee56a7d10da904 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -1187,12 +1187,6 @@ The underlying reason for the above rules is to make sure, that a mount can be accurately replicated (e.g. umounting and mounting again) based on the information found in /proc/mounts. -A simple method of saving options at mount/remount time and showing -them is provided with the save_mount_options() and -generic_show_options() helper functions. Please note, that using -these may have drawbacks. For more info see header comments for these -functions in fs/namespace.c. - Resources ========= diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index d7a7c53803c1bf..5b68e4294faa53 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -29,7 +29,6 @@ static const struct super_operations efivarfs_ops = { .statfs = simple_statfs, .drop_inode = generic_delete_inode, .evict_inode = efivarfs_evict_inode, - .show_options = generic_show_options, }; static struct super_block *efivarfs_sb; diff --git a/fs/namespace.c b/fs/namespace.c index 544ab84642ebde..0e1fdb30613368 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1237,65 +1237,6 @@ struct vfsmount *mnt_clone_internal(const struct path *path) return &p->mnt; } -static inline void mangle(struct seq_file *m, const char *s) -{ - seq_escape(m, s, " \t\n\\"); -} - -/* - * Simple .show_options callback for filesystems which don't want to - * implement more complex mount option showing. - * - * See also save_mount_options(). - */ -int generic_show_options(struct seq_file *m, struct dentry *root) -{ - const char *options; - - rcu_read_lock(); - options = rcu_dereference(root->d_sb->s_options); - - if (options != NULL && options[0]) { - seq_putc(m, ','); - mangle(m, options); - } - rcu_read_unlock(); - - return 0; -} -EXPORT_SYMBOL(generic_show_options); - -/* - * If filesystem uses generic_show_options(), this function should be - * called from the fill_super() callback. - * - * The .remount_fs callback usually needs to be handled in a special - * way, to make sure, that previous options are not overwritten if the - * remount fails. - * - * Also note, that if the filesystem's .remount_fs function doesn't - * reset all options to their default value, but changes only newly - * given options, then the displayed options will not reflect reality - * any more. - */ -void save_mount_options(struct super_block *sb, char *options) -{ - BUG_ON(sb->s_options); - rcu_assign_pointer(sb->s_options, kstrdup(options, GFP_KERNEL)); -} -EXPORT_SYMBOL(save_mount_options); - -void replace_mount_options(struct super_block *sb, char *options) -{ - char *old = sb->s_options; - rcu_assign_pointer(sb->s_options, options); - if (old) { - synchronize_rcu(); - kfree(old); - } -} -EXPORT_SYMBOL(replace_mount_options); - #ifdef CONFIG_PROC_FS /* iterator; we want it to have access to namespace_sem, thus here... */ static void *m_start(struct seq_file *m, loff_t *pos) diff --git a/fs/super.c b/fs/super.c index dfb56a9665d85c..6bc3352adcf39f 100644 --- a/fs/super.c +++ b/fs/super.c @@ -168,7 +168,6 @@ static void destroy_super(struct super_block *s) WARN_ON(!list_empty(&s->s_mounts)); put_user_ns(s->s_user_ns); kfree(s->s_subtype); - kfree(s->s_options); call_rcu(&s->rcu, destroy_super_rcu); } diff --git a/include/linux/fs.h b/include/linux/fs.h index bc0c054894b9e1..e265b2ea72c630 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1351,11 +1351,6 @@ struct super_block { */ char *s_subtype; - /* - * Saved mount options for lazy filesystems using - * generic_show_options() - */ - char __rcu *s_options; const struct dentry_operations *s_d_op; /* default d_op for dentries */ /* @@ -3033,10 +3028,6 @@ extern void setattr_copy(struct inode *inode, const struct iattr *attr); extern int file_update_time(struct file *file); -extern int generic_show_options(struct seq_file *m, struct dentry *root); -extern void save_mount_options(struct super_block *sb, char *options); -extern void replace_mount_options(struct super_block *sb, char *options); - static inline bool io_is_direct(struct file *filp) { return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);