All of lore.kernel.org
 help / color / mirror / Atom feed
From: trondmy@kernel.org
To: linux-nfs@vger.kernel.org
Subject: [PATCH v2 1/3] NFS: Fix an Oopsable condition in __nfs_pageio_add_request()
Date: Tue, 25 May 2021 14:02:39 -0400	[thread overview]
Message-ID: <20210525180241.261090-1-trondmy@kernel.org> (raw)

From: Trond Myklebust <trond.myklebust@hammerspace.com>

Ensure that nfs_pageio_error_cleanup() resets the mirror array contents,
so that the structure reflects the fact that it is now empty.
Also change the test in nfs_pageio_do_add_request() to be more robust by
checking whether or not the list is empty rather than relying on the
value of pg_count.

Fixes: a7d42ddb3099 ("nfs: add mirroring support to pgio layer")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/pagelist.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 6c20b28d9d7c..d35c84af44e0 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -1094,15 +1094,16 @@ nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
 	struct nfs_page *prev = NULL;
 	unsigned int size;
 
-	if (mirror->pg_count != 0) {
-		prev = nfs_list_entry(mirror->pg_list.prev);
-	} else {
+	if (list_empty(&mirror->pg_list)) {
 		if (desc->pg_ops->pg_init)
 			desc->pg_ops->pg_init(desc, req);
 		if (desc->pg_error < 0)
 			return 0;
 		mirror->pg_base = req->wb_pgbase;
-	}
+		mirror->pg_count = 0;
+		mirror->pg_recoalesce = 0;
+	} else
+		prev = nfs_list_entry(mirror->pg_list.prev);
 
 	if (desc->pg_maxretrans && req->wb_nio > desc->pg_maxretrans) {
 		if (NFS_SERVER(desc->pg_inode)->flags & NFS_MOUNT_SOFTERR)
-- 
2.31.1


             reply	other threads:[~2021-05-25 18:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-25 18:02 trondmy [this message]
2021-05-25 18:02 ` [PATCH v2 2/3] NFS: Don't corrupt the value of pg_bytes_written in nfs_do_recoalesce() trondmy
2021-05-25 18:02   ` [PATCH v2 3/3] NFS: Clean up reset of the mirror accounting variables trondmy

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210525180241.261090-1-trondmy@kernel.org \
    --to=trondmy@kernel.org \
    --cc=linux-nfs@vger.kernel.org \
    --subject='Re: [PATCH v2 1/3] NFS: Fix an Oopsable condition in __nfs_pageio_add_request()' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.