From 7c96a2ee45be41d5a167e6332d202086752c36bb Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Fri, 11 Jun 2021 13:40:55 -0400 Subject: [PATCH] NFSv4: Fix an Oops in pnfs_mark_request_commit() when doing O_DIRECT [ Upstream commit 3731d44bba8e0116b052b1b374476c5f6dd9a456 ] Fix an Oopsable condition in pnfs_mark_request_commit() when we're putting a set of writes on the commit list to reschedule them after a failed pNFS attempt. Fixes: 9c455a8c1e14 ("NFS/pNFS: Clean up pNFS commit operations") Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/nfs/direct.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 2d30a4da49fa0..2e894fec036b0 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -700,8 +700,8 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) { struct nfs_direct_req *dreq = hdr->dreq; struct nfs_commit_info cinfo; - bool request_commit = false; struct nfs_page *req = nfs_list_entry(hdr->pages.next); + int flags = NFS_ODIRECT_DONE; nfs_init_cinfo_from_dreq(&cinfo, dreq); @@ -713,15 +713,9 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) nfs_direct_count_bytes(dreq, hdr); if (hdr->good_bytes != 0 && nfs_write_need_commit(hdr)) { - switch (dreq->flags) { - case 0: + if (!dreq->flags) dreq->flags = NFS_ODIRECT_DO_COMMIT; - request_commit = true; - break; - case NFS_ODIRECT_RESCHED_WRITES: - case NFS_ODIRECT_DO_COMMIT: - request_commit = true; - } + flags = dreq->flags; } spin_unlock(&dreq->lock); @@ -729,12 +723,15 @@ static void nfs_direct_write_completion(struct nfs_pgio_header *hdr) req = nfs_list_entry(hdr->pages.next); nfs_list_remove_request(req); - if (request_commit) { + if (flags == NFS_ODIRECT_DO_COMMIT) { kref_get(&req->wb_kref); memcpy(&req->wb_verf, &hdr->verf.verifier, sizeof(req->wb_verf)); nfs_mark_request_commit(req, hdr->lseg, &cinfo, hdr->ds_commit_idx); + } else if (flags == NFS_ODIRECT_RESCHED_WRITES) { + kref_get(&req->wb_kref); + nfs_mark_request_commit(req, NULL, &cinfo, 0); } nfs_unlock_and_release_request(req); }