From: Trond Myklebust <[email protected]>
Be more careful when tearing down the subrequests of an O_DIRECT write
as part of a retransmission.
Reported-by: Chris Mason <[email protected]>
Fixes: ed5d588fe47f ("NFS: Try to join page groups before an O_DIRECT retransmission")
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/direct.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 9a18c5a69ace..aaffaaa336cc 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -472,20 +472,26 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter,
return result;
}
-static void
-nfs_direct_join_group(struct list_head *list, struct inode *inode)
+static void nfs_direct_join_group(struct list_head *list, struct inode *inode)
{
- struct nfs_page *req, *next;
+ struct nfs_page *req, *subreq;
list_for_each_entry(req, list, wb_list) {
- if (req->wb_head != req || req->wb_this_page == req)
+ if (req->wb_head != req)
continue;
- for (next = req->wb_this_page;
- next != req->wb_head;
- next = next->wb_this_page) {
- nfs_list_remove_request(next);
- nfs_release_request(next);
- }
+ subreq = req->wb_this_page;
+ if (subreq == req)
+ continue;
+ do {
+ /*
+ * Remove subrequests from this list before freeing
+ * them in the call to nfs_join_page_group().
+ */
+ if (!list_empty(&subreq->wb_list)) {
+ nfs_list_remove_request(subreq);
+ nfs_release_request(subreq);
+ }
+ } while ((subreq = subreq->wb_this_page) != req);
nfs_join_page_group(req, inode);
}
}
--
2.41.0
From: Trond Myklebust <[email protected]>
We must ensure that the subrequests are joined back into the head before
we can retransmit a request. If the head was not on the commit lists,
because the server wrote it synchronously, we still need to add it back
to the retransmission list.
Add a call that mirrors the effect of nfs_cancel_remove_inode() for
O_DIRECT.
Fixes: ed5d588fe47f ("NFS: Try to join page groups before an O_DIRECT retransmission")
Signed-off-by: Trond Myklebust <[email protected]>
---
fs/nfs/direct.c | 19 ++++++++++++++++++-
1 file changed, 18 insertions(+), 1 deletion(-)
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index aaffaaa336cc..9b6bfc7905f6 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -472,13 +472,30 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter,
return result;
}
+static void nfs_direct_add_page_head(struct list_head *list,
+ struct nfs_page *req)
+{
+ struct nfs_page *head = req->wb_head;
+
+ if (!list_empty(&head->wb_list) || !nfs_lock_request(head))
+ return;
+ if (!list_empty(&head->wb_list)) {
+ nfs_unlock_request(head);
+ return;
+ }
+ list_add(&head->wb_list, list);
+ kref_get(&head->wb_kref);
+}
+
static void nfs_direct_join_group(struct list_head *list, struct inode *inode)
{
struct nfs_page *req, *subreq;
list_for_each_entry(req, list, wb_list) {
- if (req->wb_head != req)
+ if (req->wb_head != req) {
+ nfs_direct_add_page_head(&req->wb_list, req);
continue;
+ }
subreq = req->wb_this_page;
if (subreq == req)
continue;
--
2.41.0