This patch reverts mostly commit 40595cdc93ed ("nfs: block notification
on fs with its own ->lock") and introduces an EXPORT_OP_SAFE_ASYNC_LOCK
export flag to signal that the "own ->lock" implementation supports
async lock requests. The only main user is DLM that is used by GFS2 and
OCFS2 filesystem. Those implement their own lock() implementation and
return FILE_LOCK_DEFERRED as return value. Since commit 40595cdc93ed
("nfs: block notification on fs with its own ->lock") the DLM
implementation were never updated. This patch should prepare for DLM
to set the EXPORT_OP_SAFE_ASYNC_LOCK export flag and update the DLM
plock implementation regarding to it.
Acked-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Alexander Aring <aahringo@xxxxxxxxxx>
---
fs/lockd/svclock.c | 5 ++---
fs/nfsd/nfs4state.c | 13 ++++++++++---
include/linux/exportfs.h | 8 ++++++++
3 files changed, 20 insertions(+), 6 deletions(-)
diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
index c43ccdf28ed9..6e3b230e8317 100644
--- a/fs/lockd/svclock.c
+++ b/fs/lockd/svclock.c
@@ -470,9 +470,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
struct nlm_host *host, struct nlm_lock *lock, int wait,
struct nlm_cookie *cookie, int reclaim)
{
-#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
struct inode *inode = nlmsvc_file_inode(file);
-#endif
struct nlm_block *block = NULL;
int error;
int mode;
@@ -486,7 +484,8 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
(long long)lock->fl.fl_end,
wait);
- if (nlmsvc_file_file(file)->f_op->lock) {
+ if (!export_op_support_safe_async_lock(inode->i_sb->s_export_op,
+ nlmsvc_file_file(file)->f_op)) {
async_block = wait;
wait = 0;
}
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 3aefbad4cc09..14ca06424ff1 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -7430,6 +7430,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
struct nfsd4_blocked_lock *nbl = NULL;
struct file_lock *file_lock = NULL;
struct file_lock *conflock = NULL;
+ struct super_block *sb;
__be32 status = 0;
int lkflg;
int err;
@@ -7451,6 +7452,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
dprintk("NFSD: nfsd4_lock: permission denied!\n");
return status;
}
+ sb = cstate->current_fh.fh_dentry->d_sb;
if (lock->lk_is_new) {
if (nfsd4_has_session(cstate))
@@ -7502,7 +7504,9 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
fp = lock_stp->st_stid.sc_file;
switch (lock->lk_type) {
case NFS4_READW_LT:
- if (nfsd4_has_session(cstate))
+ if (nfsd4_has_session(cstate) ||
+ export_op_support_safe_async_lock(sb->s_export_op,
+ nf->nf_file->f_op))
fl_flags |= FL_SLEEP;
fallthrough;
case NFS4_READ_LT:
@@ -7514,7 +7518,9 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
fl_type = F_RDLCK;
break;
case NFS4_WRITEW_LT:
- if (nfsd4_has_session(cstate))
+ if (nfsd4_has_session(cstate) ||
+ export_op_support_safe_async_lock(sb->s_export_op,
+ nf->nf_file->f_op))
fl_flags |= FL_SLEEP;
fallthrough;
case NFS4_WRITE_LT:
@@ -7542,7 +7548,8 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
* for file locks), so don't attempt blocking lock notifications
* on those filesystems:
*/
- if (nf->nf_file->f_op->lock)
+ if (!export_op_support_safe_async_lock(sb->s_export_op,
+ nf->nf_file->f_op))
fl_flags &= ~FL_SLEEP;
nbl = find_or_allocate_block(lock_sop, &fp->fi_fhandle, nn);
diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h
index 11fbd0ee1370..10358a93cdc1 100644
--- a/include/linux/exportfs.h
+++ b/include/linux/exportfs.h
@@ -3,6 +3,7 @@
#define LINUX_EXPORTFS_H 1
#include <linux/types.h>
+#include <linux/fs.h>
struct dentry;
struct iattr;
@@ -224,9 +225,16 @@ struct export_operations {
atomic attribute updates
*/
#define EXPORT_OP_FLUSH_ON_CLOSE (0x20) /* fs flushes file data on close */
+#define EXPORT_OP_SAFE_ASYNC_LOCK (0x40) /* fs can do async lock request */
unsigned long flags;
};
+static inline bool export_op_support_safe_async_lock(const struct export_operations *export_ops,
+ const struct file_operations *f_op)
+{
+ return (export_ops->flags & EXPORT_OP_SAFE_ASYNC_LOCK) || !f_op->lock;
+}
+
extern int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid,
int *max_len, struct inode *parent,
int flags);
--
2.31.1
