From 6b8aa129dcbe0e9825109b35c4b967f984e8fb13 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 21 Jun 2017 15:28:35 +0300 Subject: [PATCH] ovl: generalize ovl_create_workdir() Pass in the subdir name to create and specify if subdir is persistent or if it should be cleaned up on every mount. Move fallback to readonly mount on failure to create dir and print of error message into the helper. This function is going to be used for creating the persistent 'index' dir under workbasedir. Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/super.c | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index b31637727021..fea7bd496f2e 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -418,22 +418,27 @@ static int ovl_parse_opt(char *opt, struct ovl_config *config) #define OVL_WORKDIR_NAME "work" -static struct dentry *ovl_workdir_create(struct vfsmount *mnt, - struct dentry *dentry) +static struct dentry *ovl_workdir_create(struct super_block *sb, + struct ovl_fs *ufs, + struct dentry *dentry, + const char *name, bool persist) { struct inode *dir = dentry->d_inode; + struct vfsmount *mnt = ufs->upper_mnt; struct dentry *work; int err; bool retried = false; + bool locked = false; err = mnt_want_write(mnt); if (err) - return ERR_PTR(err); + goto out_err; inode_lock_nested(dir, I_MUTEX_PARENT); + locked = true; + retry: - work = lookup_one_len(OVL_WORKDIR_NAME, dentry, - strlen(OVL_WORKDIR_NAME)); + work = lookup_one_len(name, dentry, strlen(name)); if (!IS_ERR(work)) { struct iattr attr = { @@ -446,6 +451,9 @@ retry: if (retried) goto out_dput; + if (persist) + goto out_unlock; + retried = true; ovl_workdir_cleanup(dir, mnt, work, 0); dput(work); @@ -485,16 +493,24 @@ retry: inode_unlock(work->d_inode); if (err) goto out_dput; + } else { + err = PTR_ERR(work); + goto out_err; } out_unlock: - inode_unlock(dir); mnt_drop_write(mnt); + if (locked) + inode_unlock(dir); return work; out_dput: dput(work); - work = ERR_PTR(err); +out_err: + pr_warn("overlayfs: failed to create directory %s/%s (errno: %i); mounting read-only\n", + ufs->config.workdir, name, -err); + sb->s_flags |= MS_RDONLY; + work = NULL; goto out_unlock; } @@ -906,15 +922,8 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent) sb->s_time_gran = ufs->upper_mnt->mnt_sb->s_time_gran; - ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry); - err = PTR_ERR(ufs->workdir); - if (IS_ERR(ufs->workdir)) { - pr_warn("overlayfs: failed to create directory %s/%s (errno: %i); mounting read-only\n", - ufs->config.workdir, OVL_WORKDIR_NAME, -err); - sb->s_flags |= MS_RDONLY; - ufs->workdir = NULL; - } - + ufs->workdir = ovl_workdir_create(sb, ufs, workpath.dentry, + OVL_WORKDIR_NAME, false); /* * Upper should support d_type, else whiteouts are visible. * Given workdir and upper are on same fs, we can do