ovl: rearrange copy up

Split up and rearrange copy up functions to make them better readable.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

1 files changed, 50 insertions, 36 deletions

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 58c06bd58a96..15668d3bbbc4 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -317,6 +317,7 @@ static int ovl_set_origin(struct dentry *dentry, struct dentry *lower,
 }
 
 struct ovl_copy_up_ctx {
+        struct dentry *parent;
         struct dentry *dentry;
         struct path lowerpath;
         struct kstat stat;
@@ -493,39 +494,16 @@ out_cleanup:
  * is possible that the copy up will lock the old parent.  At that point
  * the file will have already been copied up anyway.
  */
-static int ovl_copy_up_one(struct dentry *parent, struct ovl_copy_up_ctx *c)
+static int ovl_do_copy_up(struct ovl_copy_up_ctx *c)
 {
-        DEFINE_DELAYED_CALL(done);
         int err;
-        struct path parentpath;
-        struct dentry *lowerdentry = c->lowerpath.dentry;
         struct ovl_fs *ofs = c->dentry->d_sb->s_fs_info;
 
-        c->workdir = ovl_workdir(c->dentry);
-        if (WARN_ON(!c->workdir))
-                return -EROFS;
-
-        ovl_do_check_copy_up(lowerdentry);
-
-        ovl_path_upper(parent, &parentpath);
-        c->upperdir = parentpath.dentry;
-
         /* Mark parent "impure" because it may now contain non-pure upper */
-        err = ovl_set_impure(parent, c->upperdir);
-        if (err)
-                return err;
-
-        err = vfs_getattr(&parentpath, &c->pstat,
-                          STATX_ATIME | STATX_MTIME, AT_STATX_SYNC_AS_STAT);
+        err = ovl_set_impure(c->parent, c->upperdir);
         if (err)
                 return err;
 
-        if (S_ISLNK(c->stat.mode)) {
-                c->link = vfs_get_link(lowerdentry, &done);
-                if (IS_ERR(c->link))
-                        return PTR_ERR(c->link);
-        }
-
         /* Should we copyup with O_TMPFILE or with workdir? */
         if (S_ISREG(c->stat.mode) && ofs->tmpfile) {
                 err = ovl_copy_up_start(c->dentry);
@@ -558,6 +536,52 @@ static int ovl_copy_up_one(struct dentry *parent, struct ovl_copy_up_ctx *c)
 out_unlock:
         unlock_rename(c->workdir, c->upperdir);
 out_done:
+
+        return err;
+}
+
+static int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
+                           int flags)
+{
+        int err;
+        DEFINE_DELAYED_CALL(done);
+        struct path parentpath;
+        struct ovl_copy_up_ctx ctx = {
+                .parent = parent,
+                .dentry = dentry,
+                .workdir = ovl_workdir(dentry),
+        };
+
+        if (WARN_ON(!ctx.workdir))
+                return -EROFS;
+
+        ovl_path_lower(dentry, &ctx.lowerpath);
+        err = vfs_getattr(&ctx.lowerpath, &ctx.stat,
+                          STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
+        if (err)
+                return err;
+
+        ovl_path_upper(parent, &parentpath);
+        ctx.upperdir = parentpath.dentry;
+
+        err = vfs_getattr(&parentpath, &ctx.pstat,
+                          STATX_ATIME | STATX_MTIME, AT_STATX_SYNC_AS_STAT);
+        if (err)
+                return err;
+
+        /* maybe truncate regular file. this has no effect on dirs */
+        if (flags & O_TRUNC)
+                ctx.stat.size = 0;
+
+        if (S_ISLNK(ctx.stat.mode)) {
+                ctx.link = vfs_get_link(ctx.lowerpath.dentry, &done);
+                if (IS_ERR(ctx.link))
+                        return PTR_ERR(ctx.link);
+        }
+        ovl_do_check_copy_up(ctx.lowerpath.dentry);
+
+        err = ovl_do_copy_up(&ctx);
+
         do_delayed_call(&done);
 
         return err;
@@ -571,7 +595,6 @@ int ovl_copy_up_flags(struct dentry *dentry, int flags)
         while (!err) {
                 struct dentry *next;
                 struct dentry *parent;
-                struct ovl_copy_up_ctx ctx = { };
                 enum ovl_path_type type = ovl_path_type(dentry);
 
                 if (OVL_TYPE_UPPER(type))
@@ -590,16 +613,7 @@ int ovl_copy_up_flags(struct dentry *dentry, int flags)
                         next = parent;
                 }
 
-                ovl_path_lower(next, &ctx.lowerpath);
-                err = vfs_getattr(&ctx.lowerpath, &ctx.stat,
-                                  STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
-                /* maybe truncate regular file. this has no effect on dirs */
-                if (flags & O_TRUNC)
-                        ctx.stat.size = 0;
-                if (!err) {
-                        ctx.dentry = next;
-                        err = ovl_copy_up_one(parent, &ctx);
-                }
+                err = ovl_copy_up_one(parent, next, flags);
 
                 dput(parent);
                 dput(next);