path: root/fs/nfs/pnfs.c
diff options
authorScott Mayhew <smayhew@redhat.com>2017-12-15 16:12:32 -0500
committerTrond Myklebust <trond.myklebust@primarydata.com>2018-01-14 23:06:29 -0500
commitba4a76f703ab7eb72941fdaac848502073d6e9ee (patch)
treed2a7374a5b6e01c3f34f94230e8533c3a0a19616 /fs/nfs/pnfs.c
parentpnfs/blocklayout: handle transient devices (diff)
nfs/pnfs: fix nfs_direct_req ref leak when i/o falls back to the mds
Currently when falling back to doing I/O through the MDS (via pnfs_{read|write}_through_mds), the client frees the nfs_pgio_header without releasing the reference taken on the dreq via pnfs_generic_pg_{read|write}pages -> nfs_pgheader_init -> nfs_direct_pgio_init. It then takes another reference on the dreq via nfs_generic_pg_pgios -> nfs_pgheader_init -> nfs_direct_pgio_init and as a result the requester will become stuck in inode_dio_wait. Once that happens, other processes accessing the inode will become stuck as well. Ensure that pnfs_read_through_mds() and pnfs_write_through_mds() clean up correctly by calling hdr->completion_ops->completion() instead of calling hdr->release() directly. This can be reproduced (sometimes) by performing "storage failover takeover" commands on NetApp filer while doing direct I/O from a client. This can also be reproduced using SystemTap to simulate a failure while doing direct I/O from a client (from Dave Wysochanski <dwysocha@redhat.com>): stap -v -g -e 'probe module("nfs_layout_nfsv41_files").function("nfs4_fl_prepare_ds").return { $return=NULL; exit(); }' Suggested-by: Trond Myklebust <trond.myklebust@primarydata.com> Signed-off-by: Scott Mayhew <smayhew@redhat.com> Fixes: 1ca018d28d ("pNFS: Fix a memory leak when attempted pnfs fails") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs/pnfs.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index b3dae6ec2d39..c13e826614b5 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2255,7 +2255,7 @@ pnfs_write_through_mds(struct nfs_pageio_descriptor *desc,
mirror->pg_recoalesce = 1;
- hdr->release(hdr);
+ hdr->completion_ops->completion(hdr);
static enum pnfs_try_status
@@ -2378,7 +2378,7 @@ pnfs_read_through_mds(struct nfs_pageio_descriptor *desc,
mirror->pg_recoalesce = 1;
- hdr->release(hdr);
+ hdr->completion_ops->completion(hdr);