From fa7c1d5080f6e7dc4428210b6eac60271f899908 Mon Sep 17 00:00:00 2001 From: Mateusz Guzik Date: Tue, 3 Oct 2017 18:17:40 +0200 Subject: vfs: factor sb iteration out of do_emergency_remount The intent is to reduce code duplication with other code iterating the list. No functional changes. Signed-off-by: Mateusz Guzik Signed-off-by: Al Viro --- fs/super.c | 61 ++++++++++++++++++++++++++++++++++++------------------------- 1 file changed, 36 insertions(+), 25 deletions(-) (limited to 'fs') diff --git a/fs/super.c b/fs/super.c index 166c4ee0d0ed..fd9c02f543eb 100644 --- a/fs/super.c +++ b/fs/super.c @@ -574,6 +574,28 @@ void drop_super_exclusive(struct super_block *sb) } EXPORT_SYMBOL(drop_super_exclusive); +static void __iterate_supers(void (*f)(struct super_block *)) +{ + struct super_block *sb, *p = NULL; + + spin_lock(&sb_lock); + list_for_each_entry(sb, &super_blocks, s_list) { + if (hlist_unhashed(&sb->s_instances)) + continue; + sb->s_count++; + spin_unlock(&sb_lock); + + f(sb); + + spin_lock(&sb_lock); + if (p) + __put_super(p); + p = sb; + } + if (p) + __put_super(p); + spin_unlock(&sb_lock); +} /** * iterate_supers - call function for all active superblocks * @f: function to call @@ -881,33 +903,22 @@ cancel_readonly: return retval; } -static void do_emergency_remount(struct work_struct *work) +static void do_emergency_remount_callback(struct super_block *sb) { - struct super_block *sb, *p = NULL; - - spin_lock(&sb_lock); - list_for_each_entry(sb, &super_blocks, s_list) { - if (hlist_unhashed(&sb->s_instances)) - continue; - sb->s_count++; - spin_unlock(&sb_lock); - down_write(&sb->s_umount); - if (sb->s_root && sb->s_bdev && (sb->s_flags & SB_BORN) && - !sb_rdonly(sb)) { - /* - * What lock protects sb->s_flags?? - */ - do_remount_sb(sb, SB_RDONLY, NULL, 1); - } - up_write(&sb->s_umount); - spin_lock(&sb_lock); - if (p) - __put_super(p); - p = sb; + down_write(&sb->s_umount); + if (sb->s_root && sb->s_bdev && (sb->s_flags & SB_BORN) && + !sb_rdonly(sb)) { + /* + * What lock protects sb->s_flags?? + */ + do_remount_sb(sb, SB_RDONLY, NULL, 1); } - if (p) - __put_super(p); - spin_unlock(&sb_lock); + up_write(&sb->s_umount); +} + +static void do_emergency_remount(struct work_struct *work) +{ + __iterate_supers(do_emergency_remount_callback); kfree(work); printk("Emergency Remount complete\n"); } -- cgit v1.2.3