pnfs_nfs: fix _cancel_empty_pagelist

pnfs_generic_commit_cancel_empty_pagelist calls nfs_commitdata_release,
but that is wrong: nfs_commitdata_release puts the open context, something
that isn't valid until nfs_init_commit is called, which is never the case
when pnfs_generic_commit_cancel_empty_pagelist is called.

This was introduced in "nfs: avoid race that crashes nfs_init_commit".

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This commit is contained in:
Weston Andros Adamson 2016-06-17 16:48:24 -04:00 committed by Anna Schumaker
parent cea7f829d3
commit 5e3a98883e
1 changed files with 10 additions and 2 deletions

View File

@ -247,7 +247,11 @@ void pnfs_fetch_commit_bucket_list(struct list_head *pages,
}
/* Helper function for pnfs_generic_commit_pagelist to catch an empty
* page list. This can happen when two commits race. */
* page list. This can happen when two commits race.
*
* This must be called instead of nfs_init_commit - call one or the other, but
* not both!
*/
static bool
pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
struct nfs_commit_data *data,
@ -256,7 +260,11 @@ pnfs_generic_commit_cancel_empty_pagelist(struct list_head *pages,
if (list_empty(pages)) {
if (atomic_dec_and_test(&cinfo->mds->rpcs_out))
wake_up_atomic_t(&cinfo->mds->rpcs_out);
nfs_commitdata_release(data);
/* don't call nfs_commitdata_release - it tries to put
* the open_context which is not acquired until nfs_init_commit
* which has not been called on @data */
WARN_ON_ONCE(data->context);
nfs_commit_free(data);
return true;
}