[PATCH 12/13] afs: Invoke fscache_resize_cookie() when handling ATTR_SIZE for setattr

[David Howells]

Invoke fscache_resize_cookie() to adjust the size of the backing cache
object when setattr is called with ATTR_SIZE.  This discards any data that
then lies beyond the revised EOF and frees up space.

Signed-off-by: David Howells <dhowe...@redhat.com>
---

 fs/afs/inode.c |   24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index eab191b9c01d..baaaa5e55f95 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -815,14 +815,19 @@ void afs_evict_inode(struct inode *inode)
 
 static void afs_setattr_success(struct afs_operation *op)
 {
-       struct inode *inode = &op->file[0].vnode->vfs_inode;
+       struct afs_vnode_param *vp = &op->file[0];
+       struct inode *inode = &vp->vnode->vfs_inode;
 
-       afs_vnode_commit_status(op, &op->file[0]);
+       afs_vnode_commit_status(op, vp);
        if (op->setattr.attr->ia_valid & ATTR_SIZE) {
                loff_t i_size = inode->i_size, size = op->setattr.attr->ia_size;
+
                if (size > i_size)
                        pagecache_isize_extended(inode, i_size, size);
                truncate_pagecache(inode, size);
+
+               fscache_resize_cookie(afs_vnode_cache(vp->vnode),
+                                     vp->scb.status.size);
        }
 }
 
@@ -864,6 +869,8 @@ int afs_setattr(struct dentry *dentry, struct iattr *attr)
                        attr->ia_valid &= ~ATTR_SIZE;
        }
 
+       fscache_use_cookie(afs_vnode_cache(vnode), true);
+
        /* flush any dirty data outstanding on a regular file */
        if (S_ISREG(vnode->vfs_inode.i_mode))
                filemap_write_and_wait(vnode->vfs_inode.i_mapping);
@@ -871,8 +878,10 @@ int afs_setattr(struct dentry *dentry, struct iattr *attr)
        op = afs_alloc_operation(((attr->ia_valid & ATTR_FILE) ?
                                  afs_file_key(attr->ia_file) : NULL),
                                 vnode->volume);
-       if (IS_ERR(op))
-               return PTR_ERR(op);
+       if (IS_ERR(op)) {
+               ret = PTR_ERR(op);
+               goto error_unuse;
+       }
 
        afs_op_set_vnode(op, 0, vnode);
        op->setattr.attr = attr;
@@ -885,5 +894,10 @@ int afs_setattr(struct dentry *dentry, struct iattr *attr)
        op->file[0].update_ctime = 1;
 
        op->ops = &afs_setattr_operation;
-       return afs_do_sync_operation(op);
+       ret = afs_do_sync_operation(op);
+
+error_unuse:
+       fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);
+       _leave(" = %d", ret);
+       return ret;
 }