v4.19.13 snapshot.
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
new file mode 100644
index 0000000..4288a6e
--- /dev/null
+++ b/fs/nfs/nfs4file.c
@@ -0,0 +1,269 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/nfs/file.c
+ *
+ * Copyright (C) 1992 Rick Sladkey
+ */
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/falloc.h>
+#include <linux/nfs_fs.h>
+#include "delegation.h"
+#include "internal.h"
+#include "iostat.h"
+#include "fscache.h"
+#include "pnfs.h"
+
+#include "nfstrace.h"
+
+#ifdef CONFIG_NFS_V4_2
+#include "nfs42.h"
+#endif
+
+#define NFSDBG_FACILITY NFSDBG_FILE
+
+static int
+nfs4_file_open(struct inode *inode, struct file *filp)
+{
+ struct nfs_open_context *ctx;
+ struct dentry *dentry = file_dentry(filp);
+ struct dentry *parent = NULL;
+ struct inode *dir;
+ unsigned openflags = filp->f_flags;
+ struct iattr attr;
+ int err;
+
+ /*
+ * If no cached dentry exists or if it's negative, NFSv4 handled the
+ * opens in ->lookup() or ->create().
+ *
+ * We only get this far for a cached positive dentry. We skipped
+ * revalidation, so handle it here by dropping the dentry and returning
+ * -EOPENSTALE. The VFS will retry the lookup/create/open.
+ */
+
+ dprintk("NFS: open file(%pd2)\n", dentry);
+
+ err = nfs_check_flags(openflags);
+ if (err)
+ return err;
+
+ if ((openflags & O_ACCMODE) == 3)
+ openflags--;
+
+ /* We can't create new files here */
+ openflags &= ~(O_CREAT|O_EXCL);
+
+ parent = dget_parent(dentry);
+ dir = d_inode(parent);
+
+ ctx = alloc_nfs_open_context(file_dentry(filp), filp->f_mode, filp);
+ err = PTR_ERR(ctx);
+ if (IS_ERR(ctx))
+ goto out;
+
+ attr.ia_valid = ATTR_OPEN;
+ if (openflags & O_TRUNC) {
+ attr.ia_valid |= ATTR_SIZE;
+ attr.ia_size = 0;
+ filemap_write_and_wait(inode->i_mapping);
+ }
+
+ inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, &attr, NULL);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ switch (err) {
+ case -EPERM:
+ case -EACCES:
+ case -EDQUOT:
+ case -ENOSPC:
+ case -EROFS:
+ goto out_put_ctx;
+ default:
+ goto out_drop;
+ }
+ }
+ if (inode != d_inode(dentry))
+ goto out_drop;
+
+ nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+ nfs_file_set_open_context(filp, ctx);
+ nfs_fscache_open_file(inode, filp);
+ err = 0;
+
+out_put_ctx:
+ put_nfs_open_context(ctx);
+out:
+ dput(parent);
+ return err;
+
+out_drop:
+ d_drop(dentry);
+ err = -EOPENSTALE;
+ goto out_put_ctx;
+}
+
+/*
+ * Flush all dirty pages, and check for write errors.
+ */
+static int
+nfs4_file_flush(struct file *file, fl_owner_t id)
+{
+ struct inode *inode = file_inode(file);
+
+ dprintk("NFS: flush(%pD2)\n", file);
+
+ nfs_inc_stats(inode, NFSIOS_VFSFLUSH);
+ if ((file->f_mode & FMODE_WRITE) == 0)
+ return 0;
+
+ /*
+ * If we're holding a write delegation, then check if we're required
+ * to flush the i/o on close. If not, then just start the i/o now.
+ */
+ if (!nfs4_delegation_flush_on_close(inode))
+ return filemap_fdatawrite(file->f_mapping);
+
+ /* Flush writes to the server and return any errors */
+ return vfs_fsync(file, 0);
+}
+
+#ifdef CONFIG_NFS_V4_2
+static ssize_t nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
+ struct file *file_out, loff_t pos_out,
+ size_t count, unsigned int flags)
+{
+ ssize_t ret;
+
+ if (file_inode(file_in) == file_inode(file_out))
+ return -EINVAL;
+retry:
+ ret = nfs42_proc_copy(file_in, pos_in, file_out, pos_out, count);
+ if (ret == -EAGAIN)
+ goto retry;
+ return ret;
+}
+
+static loff_t nfs4_file_llseek(struct file *filep, loff_t offset, int whence)
+{
+ loff_t ret;
+
+ switch (whence) {
+ case SEEK_HOLE:
+ case SEEK_DATA:
+ ret = nfs42_proc_llseek(filep, offset, whence);
+ if (ret != -ENOTSUPP)
+ return ret;
+ /* Fall through */
+ default:
+ return nfs_file_llseek(filep, offset, whence);
+ }
+}
+
+static long nfs42_fallocate(struct file *filep, int mode, loff_t offset, loff_t len)
+{
+ struct inode *inode = file_inode(filep);
+ long ret;
+
+ if (!S_ISREG(inode->i_mode))
+ return -EOPNOTSUPP;
+
+ if ((mode != 0) && (mode != (FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE)))
+ return -EOPNOTSUPP;
+
+ ret = inode_newsize_ok(inode, offset + len);
+ if (ret < 0)
+ return ret;
+
+ if (mode & FALLOC_FL_PUNCH_HOLE)
+ return nfs42_proc_deallocate(filep, offset, len);
+ return nfs42_proc_allocate(filep, offset, len);
+}
+
+static int nfs42_clone_file_range(struct file *src_file, loff_t src_off,
+ struct file *dst_file, loff_t dst_off, u64 count)
+{
+ struct inode *dst_inode = file_inode(dst_file);
+ struct nfs_server *server = NFS_SERVER(dst_inode);
+ struct inode *src_inode = file_inode(src_file);
+ unsigned int bs = server->clone_blksize;
+ bool same_inode = false;
+ int ret;
+
+ /* check alignment w.r.t. clone_blksize */
+ ret = -EINVAL;
+ if (bs) {
+ if (!IS_ALIGNED(src_off, bs) || !IS_ALIGNED(dst_off, bs))
+ goto out;
+ if (!IS_ALIGNED(count, bs) && i_size_read(src_inode) != (src_off + count))
+ goto out;
+ }
+
+ if (src_inode == dst_inode)
+ same_inode = true;
+
+ /* XXX: do we lock at all? what if server needs CB_RECALL_LAYOUT? */
+ if (same_inode) {
+ inode_lock(src_inode);
+ } else if (dst_inode < src_inode) {
+ inode_lock_nested(dst_inode, I_MUTEX_PARENT);
+ inode_lock_nested(src_inode, I_MUTEX_CHILD);
+ } else {
+ inode_lock_nested(src_inode, I_MUTEX_PARENT);
+ inode_lock_nested(dst_inode, I_MUTEX_CHILD);
+ }
+
+ /* flush all pending writes on both src and dst so that server
+ * has the latest data */
+ ret = nfs_sync_inode(src_inode);
+ if (ret)
+ goto out_unlock;
+ ret = nfs_sync_inode(dst_inode);
+ if (ret)
+ goto out_unlock;
+
+ ret = nfs42_proc_clone(src_file, dst_file, src_off, dst_off, count);
+
+ /* truncate inode page cache of the dst range so that future reads can fetch
+ * new data from server */
+ if (!ret)
+ truncate_inode_pages_range(&dst_inode->i_data, dst_off, dst_off + count - 1);
+
+out_unlock:
+ if (same_inode) {
+ inode_unlock(src_inode);
+ } else if (dst_inode < src_inode) {
+ inode_unlock(src_inode);
+ inode_unlock(dst_inode);
+ } else {
+ inode_unlock(dst_inode);
+ inode_unlock(src_inode);
+ }
+out:
+ return ret;
+}
+#endif /* CONFIG_NFS_V4_2 */
+
+const struct file_operations nfs4_file_operations = {
+ .read_iter = nfs_file_read,
+ .write_iter = nfs_file_write,
+ .mmap = nfs_file_mmap,
+ .open = nfs4_file_open,
+ .flush = nfs4_file_flush,
+ .release = nfs_file_release,
+ .fsync = nfs_file_fsync,
+ .lock = nfs_lock,
+ .flock = nfs_flock,
+ .splice_read = generic_file_splice_read,
+ .splice_write = iter_file_splice_write,
+ .check_flags = nfs_check_flags,
+ .setlease = simple_nosetlease,
+#ifdef CONFIG_NFS_V4_2
+ .copy_file_range = nfs4_copy_file_range,
+ .llseek = nfs4_file_llseek,
+ .fallocate = nfs42_fallocate,
+ .clone_file_range = nfs42_clone_file_range,
+#else
+ .llseek = nfs_file_llseek,
+#endif
+};