From 1e8b212fe5dcee9d3dbb152d235f3c33458fb26e Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 12 Jun 2012 16:20:46 +0200 Subject: ext2: Implement freezing The only missing piece to make freezing work reliably with ext2 is to stop iput() of unlinked inode from deleting the inode on frozen filesystem. So add a necessary protection to ext2_evict_inode(). We also provide appropriate ->freeze_fs and ->unfreeze_fs functions. Signed-off-by: Jan Kara Signed-off-by: Al Viro --- fs/ext2/inode.c | 5 ++++- fs/ext2/super.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+), 1 deletion(-) (limited to 'fs/ext2') diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 264d315..6363ac6 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -79,6 +79,7 @@ void ext2_evict_inode(struct inode * inode) truncate_inode_pages(&inode->i_data, 0); if (want_delete) { + sb_start_intwrite(inode->i_sb); /* set dtime */ EXT2_I(inode)->i_dtime = get_seconds(); mark_inode_dirty(inode); @@ -98,8 +99,10 @@ void ext2_evict_inode(struct inode * inode) if (unlikely(rsv)) kfree(rsv); - if (want_delete) + if (want_delete) { ext2_free_inode(inode); + sb_end_intwrite(inode->i_sb); + } } typedef struct { diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 5df3d2d..15761e6 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -42,6 +42,8 @@ static void ext2_sync_super(struct super_block *sb, static int ext2_remount (struct super_block * sb, int * flags, char * data); static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf); static int ext2_sync_fs(struct super_block *sb, int wait); +static int ext2_freeze(struct super_block *sb); +static int ext2_unfreeze(struct super_block *sb); void ext2_error(struct super_block *sb, const char *function, const char *fmt, ...) @@ -305,6 +307,8 @@ static const struct super_operations ext2_sops = { .evict_inode = ext2_evict_inode, .put_super = ext2_put_super, .sync_fs = ext2_sync_fs, + .freeze_fs = ext2_freeze, + .unfreeze_fs = ext2_unfreeze, .statfs = ext2_statfs, .remount_fs = ext2_remount, .show_options = ext2_show_options, @@ -1200,6 +1204,35 @@ static int ext2_sync_fs(struct super_block *sb, int wait) return 0; } +static int ext2_freeze(struct super_block *sb) +{ + struct ext2_sb_info *sbi = EXT2_SB(sb); + + /* + * Open but unlinked files present? Keep EXT2_VALID_FS flag cleared + * because we have unattached inodes and thus filesystem is not fully + * consistent. + */ + if (atomic_long_read(&sb->s_remove_count)) { + ext2_sync_fs(sb, 1); + return 0; + } + /* Set EXT2_FS_VALID flag */ + spin_lock(&sbi->s_lock); + sbi->s_es->s_state = cpu_to_le16(sbi->s_mount_state); + spin_unlock(&sbi->s_lock); + ext2_sync_super(sb, sbi->s_es, 1); + + return 0; +} + +static int ext2_unfreeze(struct super_block *sb) +{ + /* Just write sb to clear EXT2_VALID_FS flag */ + ext2_write_super(sb); + + return 0; +} void ext2_write_super(struct super_block *sb) { -- cgit v1.1