On 2014/12/11 10:30, hujianyang wrote: > Since the ovl_dir_cache is stable during a directory reading, the cursor > of struct ovl_dir_file don't need to be an independent entry in the list > of a merged directory. > > This patch changes *cursor* to a pointer which points to the entry in the > ovl_dir_cache. After this, we don't need to check *is_cursor* either. > > Signed-off-by: hujianyang <[email protected]> > --- > fs/overlayfs/readdir.c | 33 ++++++++++++--------------------- > 1 files changed, 12 insertions(+), 21 deletions(-) > > diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c > index 8087b63..b65e1ed 100644 > --- a/fs/overlayfs/readdir.c > +++ b/fs/overlayfs/readdir.c > @@ -24,7 +24,6 @@ struct ovl_cache_entry { > struct list_head l_node; > struct rb_node node; > bool is_whiteout; > - bool is_cursor; > char name[]; > }; > > @@ -49,7 +48,7 @@ struct ovl_dir_file { > bool is_real; > bool is_upper; > struct ovl_dir_cache *cache; > - struct ovl_cache_entry cursor; > + struct ovl_cache_entry *cursor; > struct file *realfile; > struct file *upperfile; > }; > @@ -94,7 +93,6 @@ static struct ovl_cache_entry *ovl_cache_entry_new(const > char *name, int len, > p->type = d_type; > p->ino = ino; > p->is_whiteout = false; > - p->is_cursor = false; > } > > return p; > @@ -195,7 +193,7 @@ static void ovl_cache_put(struct ovl_dir_file *od, struct > dentry *dentry) > { > struct ovl_dir_cache *cache = od->cache; > > - list_del_init(&od->cursor.l_node); > + od->cursor = NULL; > WARN_ON(cache->refcount <= 0); > cache->refcount--; > if (!cache->refcount) { > @@ -298,13 +296,12 @@ static void ovl_seek_cursor(struct ovl_dir_file *od, > loff_t pos) > loff_t off = 0; > > list_for_each_entry(p, &od->cache->entries, l_node) { > - if (p->is_cursor) > - continue; > if (off >= pos) > break; > off++; > } > - list_move_tail(&od->cursor.l_node, &p->l_node); > + /* Curosr is safe since the cache is stable */ > + od->cursor = p; > } > > static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry) > @@ -361,19 +358,14 @@ static int ovl_iterate(struct file *file, struct > dir_context *ctx) > ovl_seek_cursor(od, ctx->pos); > } > > - while (od->cursor.l_node.next != &od->cache->entries) { > - struct ovl_cache_entry *p; > + while (&od->cursor->l_node != &od->cache->entries) { > + struct ovl_cache_entry *p = od->cursor; > > - p = list_entry(od->cursor.l_node.next, struct ovl_cache_entry, > l_node); > - /* Skip cursors */ > - if (!p->is_cursor) { > - if (!p->is_whiteout) { > - if (!dir_emit(ctx, p->name, p->len, p->ino, > p->type)) > - break; > - } > - ctx->pos++; > - } > - list_move(&od->cursor.l_node, &p->l_node); > + if (!p->is_whiteout) > + if (!dir_emit(ctx, p->name, p->len, p->ino, p->type)) > + break; > + od->cursor = list_next_entry(p, l_node); > + ctx->pos++; > } > return 0; > } > @@ -492,11 +484,10 @@ static int ovl_dir_open(struct inode *inode, struct > file *file) > kfree(od); > return PTR_ERR(realfile); > } > - INIT_LIST_HEAD(&od->cursor.l_node); > od->realfile = realfile; > od->is_real = !OVL_TYPE_MERGE(type); > od->is_upper = OVL_TYPE_UPPER(type); > - od->cursor.is_cursor = true; > + od->cursor = NULL; > file->private_data = od; > > return 0; >
Hi Miklos, How do you feel about this cleanup? -- To unsubscribe from this list: send the line "unsubscribe linux-unionfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
