From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
If the NFSv4 client already holds a delegation for a file, then we can
support application leases (i.e. fcntl(fd, F_SETLEASE,...)) because the
underlying delegation guarantees that the file is not being modified on
the server by another client in a way that might conflict with the lease
guarantees.
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
---
fs/nfs/nfs4_fs.h | 3 ++-
fs/nfs/nfs4file.c | 8 +++++++-
fs/nfs/nfs4proc.c | 37 +++++++++++++++++++++++++++++++++++++
3 files changed, 46 insertions(+), 2 deletions(-)
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 4c44322c2643..6a04ba9e5e6a 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -322,7 +322,8 @@ extern int update_open_stateid(struct nfs4_state *state,
const nfs4_stateid *open_stateid,
const nfs4_stateid *deleg_stateid,
fmode_t fmode);
-
+extern int nfs4_proc_setlease(struct file *file, long arg,
+ struct file_lock **lease, void **priv);
extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
struct nfs_fsinfo *fsinfo);
extern void nfs4_update_changeattr(struct inode *dir,
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 57b3821d975a..aafb77f9bfdf 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -435,6 +435,12 @@ void nfs42_ssc_unregister_ops(void)
}
#endif /* CONFIG_NFS_V4_2 */
+static int nfs4_setlease(struct file *file, long arg, struct file_lock **lease,
+ void **priv)
+{
+ return nfs4_proc_setlease(file, arg, lease, priv);
+}
+
const struct file_operations nfs4_file_operations = {
.read_iter = nfs_file_read,
.write_iter = nfs_file_write,
@@ -448,7 +454,7 @@ const struct file_operations nfs4_file_operations = {
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.check_flags = nfs_check_flags,
- .setlease = simple_nosetlease,
+ .setlease = nfs4_setlease,
#ifdef CONFIG_NFS_V4_2
.copy_file_range = nfs4_copy_file_range,
.llseek = nfs4_file_llseek,
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 0cd965882232..e1abd024a492 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7420,6 +7420,43 @@ nfs4_proc_lock(struct file *filp, int cmd, struct file_lock *request)
return nfs4_retry_setlk(state, cmd, request);
}
+static int nfs4_delete_lease(struct file *file, void **priv)
+{
+ return generic_setlease(file, F_UNLCK, NULL, priv);
+}
+
+static int nfs4_add_lease(struct file *file, long arg, struct file_lock **lease,
+ void **priv)
+{
+ struct inode *inode = file_inode(file);
+ fmode_t type = arg == F_RDLCK ? FMODE_READ : FMODE_WRITE;
+ int ret;
+
+ /* No delegation, no lease */
+ if (!nfs4_have_delegation(inode, type))
+ return -ENOLCK;
+ ret = generic_setlease(file, arg, lease, priv);
+ if (ret || nfs4_have_delegation(inode, type))
+ return ret;
+ /* We raced with a delegation return */
+ nfs4_delete_lease(file, priv);
+ return -ENOLCK;
+}
+
+int nfs4_proc_setlease(struct file *file, long arg, struct file_lock **lease,
+ void **priv)
+{
+ switch (arg) {
+ case F_RDLCK:
+ case F_WRLCK:
+ return nfs4_add_lease(file, arg, lease, priv);
+ case F_UNLCK:
+ return nfs4_delete_lease(file, priv);
+ default:
+ return -EINVAL;
+ }
+}
+
int nfs4_lock_delegation_recall(struct file_lock *fl, struct nfs4_state *state, const nfs4_stateid *stateid)
{
struct nfs_server *server = NFS_SERVER(state->inode);
--
2.31.1
