diff options
author | Baptiste Lepers <baptiste.lepers@gmail.com> | 2021-09-06 11:59:24 +1000 |
---|---|---|
committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2021-10-03 23:00:50 -0400 |
commit | a2915fa06227b056a8f9b0d79b61dca08ad5cfc6 (patch) | |
tree | 5fae6438dabc0e85a70006449f3bcbc311fc8e37 /fs/nfs/flexfilelayout | |
parent | 36a10a3c4cb6ea7c8bd895c16b3f59e1f0db2f6a (diff) | |
download | linux-a2915fa06227b056a8f9b0d79b61dca08ad5cfc6.tar.bz2 |
pnfs/flexfiles: Fix misplaced barrier in nfs4_ff_layout_prepare_ds
_nfs4_pnfs_v3/v4_ds_connect do
some work
smp_wmb
ds->ds_clp = clp;
And nfs4_ff_layout_prepare_ds currently does
smp_rmb
if(ds->ds_clp)
...
This patch places the smp_rmb after the if. This ensures that following
reads only happen once nfs4_ff_layout_prepare_ds has checked that data
has been properly initialized.
Fixes: d67ae825a59d6 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Diffstat (limited to 'fs/nfs/flexfilelayout')
-rw-r--r-- | fs/nfs/flexfilelayout/flexfilelayoutdev.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c index c9b61b818ec1..bfa7202ca7be 100644 --- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c +++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c @@ -378,10 +378,10 @@ nfs4_ff_layout_prepare_ds(struct pnfs_layout_segment *lseg, goto noconnect; ds = mirror->mirror_ds->ds; + if (READ_ONCE(ds->ds_clp)) + goto out; /* matching smp_wmb() in _nfs4_pnfs_v3/4_ds_connect */ smp_rmb(); - if (ds->ds_clp) - goto out; /* FIXME: For now we assume the server sent only one version of NFS * to use for the DS. |