From 57f3f4c0cd50e90aa92eec20d9c309dd67c594a5 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 21 Apr 2016 20:51:58 -0400 Subject: nfs: have ff_layout_get_ds_cred take a reference to the cred In later patches, we're going to want to allow the creds to be updated when we get a new layout with updated creds. Have this function take a reference to the cred that is later put once the call has been dispatched. Also, prepare for this change by ensuring we follow RCU rules when getting a reference to the cred as well. Signed-off-by: Jeff Layton Signed-off-by: Anna Schumaker --- fs/nfs/flexfilelayout/flexfilelayoutdev.c | 30 ++++++++++++++++++++++++++---- 1 file changed, 26 insertions(+), 4 deletions(-) (limited to 'fs/nfs/flexfilelayout/flexfilelayoutdev.c') diff --git a/fs/nfs/flexfilelayout/flexfilelayoutdev.c b/fs/nfs/flexfilelayout/flexfilelayoutdev.c index a0dbf94d15ae..baee22929174 100644 --- a/fs/nfs/flexfilelayout/flexfilelayoutdev.c +++ b/fs/nfs/flexfilelayout/flexfilelayoutdev.c @@ -338,6 +338,25 @@ static int ff_layout_update_mirror_cred(struct nfs4_ff_layout_mirror *mirror, return 0; } +static struct rpc_cred * +ff_layout_get_mirror_cred(struct nfs4_ff_layout_mirror *mirror, u32 iomode) +{ + struct rpc_cred *cred, **pcred; + + pcred = &mirror->cred; + + rcu_read_lock(); + do { + cred = rcu_dereference(*pcred); + if (!cred) + break; + + cred = get_rpccred_rcu(cred); + } while(!cred); + rcu_read_unlock(); + return cred; +} + struct nfs_fh * nfs4_ff_layout_select_ds_fh(struct pnfs_layout_segment *lseg, u32 mirror_idx) { @@ -435,10 +454,13 @@ ff_layout_get_ds_cred(struct pnfs_layout_segment *lseg, u32 ds_idx, struct nfs4_ff_layout_mirror *mirror = FF_LAYOUT_COMP(lseg, ds_idx); struct rpc_cred *cred; - if (mirror && mirror->cred) - cred = mirror->cred; - else - cred = mdscred; + if (mirror) { + cred = ff_layout_get_mirror_cred(mirror, lseg->pls_range.iomode); + if (!cred) + cred = get_rpccred(mdscred); + } else { + cred = get_rpccred(mdscred); + } return cred; } -- cgit v1.2.3