From 4f93b426ab3930952eca6c5c456c2223a3adcbf5 Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Fri, 11 May 2018 11:49:30 -0400 Subject: ovl: Copy up meta inode data from lowest data inode So far lower could not be a meta inode. So whenever it was time to copy up data of a meta inode, we could copy it up from top most lower dentry. But now lower itself can be a metacopy inode. That means data copy up needs to take place from a data inode in metacopy inode chain. Find lower data inode in the chain and use that for data copy up. Introduced a helper called ovl_path_lowerdata() to find the lower data inode chain. Signed-off-by: Vivek Goyal Reviewed-by: Amir Goldstein Signed-off-by: Miklos Szeredi --- fs/overlayfs/copy_up.c | 13 +++++++++---- fs/overlayfs/overlayfs.h | 1 + fs/overlayfs/util.c | 12 ++++++++++++ 3 files changed, 22 insertions(+), 4 deletions(-) (limited to 'fs/overlayfs') diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c index 7e6664d6643d..d9a8d9291358 100644 --- a/fs/overlayfs/copy_up.c +++ b/fs/overlayfs/copy_up.c @@ -519,13 +519,14 @@ static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp) } if (S_ISREG(c->stat.mode) && !c->metacopy) { - struct path upperpath; + struct path upperpath, datapath; ovl_path_upper(c->dentry, &upperpath); BUG_ON(upperpath.dentry != NULL); upperpath.dentry = temp; - err = ovl_copy_up_data(&c->lowerpath, &upperpath, c->stat.size); + ovl_path_lowerdata(c->dentry, &datapath); + err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size); if (err) return err; } @@ -706,14 +707,18 @@ static bool ovl_need_meta_copy_up(struct dentry *dentry, umode_t mode, /* Copy up data of an inode which was copied up metadata only in the past. */ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c) { - struct path upperpath; + struct path upperpath, datapath; int err; ovl_path_upper(c->dentry, &upperpath); if (WARN_ON(upperpath.dentry == NULL)) return -EIO; - err = ovl_copy_up_data(&c->lowerpath, &upperpath, c->stat.size); + ovl_path_lowerdata(c->dentry, &datapath); + if (WARN_ON(datapath.dentry == NULL)) + return -EIO; + + err = ovl_copy_up_data(&datapath, &upperpath, c->stat.size); if (err) return err; diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 2de8e11db81a..a59c546c10cf 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -217,6 +217,7 @@ bool ovl_dentry_weird(struct dentry *dentry); enum ovl_path_type ovl_path_type(struct dentry *dentry); void ovl_path_upper(struct dentry *dentry, struct path *path); void ovl_path_lower(struct dentry *dentry, struct path *path); +void ovl_path_lowerdata(struct dentry *dentry, struct path *path); enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path); struct dentry *ovl_dentry_upper(struct dentry *dentry); struct dentry *ovl_dentry_lower(struct dentry *dentry); diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c index ab9a8fae0f99..32ff67fa0bfb 100644 --- a/fs/overlayfs/util.c +++ b/fs/overlayfs/util.c @@ -164,6 +164,18 @@ void ovl_path_lower(struct dentry *dentry, struct path *path) } } +void ovl_path_lowerdata(struct dentry *dentry, struct path *path) +{ + struct ovl_entry *oe = dentry->d_fsdata; + + if (oe->numlower) { + path->mnt = oe->lowerstack[oe->numlower - 1].layer->mnt; + path->dentry = oe->lowerstack[oe->numlower - 1].dentry; + } else { + *path = (struct path) { }; + } +} + enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path) { enum ovl_path_type type = ovl_path_type(dentry); -- cgit v1.2.3