4.4-stable review patch. If anyone has any objections, please let me know.
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From: NeilBrown neilb@suse.com
[ Upstream commit dce2630c7da73b0634686bca557cc8945cc450c8 ]
There are 2 comments in the NFSv4 code which suggest that SIGLOST should possibly be sent to a process. In these cases a lock has been lost. The current practice is to set NFS_LOCK_LOST so that read/write returns EIO when a lock is lost. So change these comments to code when sets NFS_LOCK_LOST.
One case is when lock recovery after apparent server restart fails with NFS4ERR_DENIED, NFS4ERR_RECLAIM_BAD, or NFS4ERRO_RECLAIM_CONFLICT. The other case is when a lock attempt as part of lease recovery fails with NFS4ERR_DENIED.
In an ideal world, these should not happen. However I have a packet trace showing an NFSv4.1 session getting NFS4ERR_BADSESSION after an extended network parition. The NFSv4.1 client treats this like server reboot until/unless it get NFS4ERR_NO_GRACE, in which case it switches over to "nograce" recovery mode. In this network trace, the client attempts to recover a lock and the server (incorrectly) reports NFS4ERR_DENIED rather than NFS4ERR_NO_GRACE. This leads to the ineffective comment and the client then continues to write using the OPEN stateid.
Signed-off-by: NeilBrown neilb@suse.com Signed-off-by: Trond Myklebust trond.myklebust@primarydata.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfs/nfs4proc.c | 12 ++++++++---- fs/nfs/nfs4state.c | 5 ++++- 2 files changed, 12 insertions(+), 5 deletions(-)
--- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1780,7 +1780,7 @@ static int nfs4_open_reclaim(struct nfs4 return ret; }
-static int nfs4_handle_delegation_recall_error(struct nfs_server *server, struct nfs4_state *state, const nfs4_stateid *stateid, int err) +static int nfs4_handle_delegation_recall_error(struct nfs_server *server, struct nfs4_state *state, const nfs4_stateid *stateid, struct file_lock *fl, int err) { switch (err) { default: @@ -1827,7 +1827,11 @@ static int nfs4_handle_delegation_recall return -EAGAIN; case -ENOMEM: case -NFS4ERR_DENIED: - /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + if (fl) { + struct nfs4_lock_state *lsp = fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); + } return 0; } return err; @@ -1863,7 +1867,7 @@ int nfs4_open_delegation_recall(struct n err = nfs4_open_recover_helper(opendata, FMODE_READ); } nfs4_opendata_put(opendata); - return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, NULL, err); }
static void nfs4_open_confirm_prepare(struct rpc_task *task, void *calldata) @@ -6157,7 +6161,7 @@ int nfs4_lock_delegation_recall(struct f if (err != 0) return err; err = _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW); - return nfs4_handle_delegation_recall_error(server, state, stateid, err); + return nfs4_handle_delegation_recall_error(server, state, stateid, fl, err); }
struct nfs_release_lockowner_data { --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -1386,6 +1386,7 @@ static int nfs4_reclaim_locks(struct nfs struct inode *inode = state->inode; struct nfs_inode *nfsi = NFS_I(inode); struct file_lock *fl; + struct nfs4_lock_state *lsp; int status = 0; struct file_lock_context *flctx = inode->i_flctx; struct list_head *list; @@ -1426,7 +1427,9 @@ restart: case -NFS4ERR_DENIED: case -NFS4ERR_RECLAIM_BAD: case -NFS4ERR_RECLAIM_CONFLICT: - /* kill_proc(fl->fl_pid, SIGLOST, 1); */ + lsp = fl->fl_u.nfs4_fl.owner; + if (lsp) + set_bit(NFS_LOCK_LOST, &lsp->ls_flags); status = 0; } spin_lock(&flctx->flc_lock);