[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/fs/ncpfs/mmap.c b/src/kernel/linux/v4.14/fs/ncpfs/mmap.c
new file mode 100644
index 0000000..a5c5cf2
--- /dev/null
+++ b/src/kernel/linux/v4.14/fs/ncpfs/mmap.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * mmap.c
+ *
+ * Copyright (C) 1995, 1996 by Volker Lendecke
+ * Modified 1997 Peter Waltenberg, Bill Hawes, David Woodhouse for 2.1 dcache
+ *
+ */
+
+#include <linux/stat.h>
+#include <linux/time.h>
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+#include <linux/shm.h>
+#include <linux/errno.h>
+#include <linux/mman.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/memcontrol.h>
+
+#include <linux/uaccess.h>
+
+#include "ncp_fs.h"
+
+/*
+ * Fill in the supplied page for mmap
+ * XXX: how are we excluding truncate/invalidate here? Maybe need to lock
+ * page?
+ */
+static int ncp_file_mmap_fault(struct vm_fault *vmf)
+{
+ struct inode *inode = file_inode(vmf->vma->vm_file);
+ char *pg_addr;
+ unsigned int already_read;
+ unsigned int count;
+ int bufsize;
+ int pos; /* XXX: loff_t ? */
+
+ /*
+ * ncpfs has nothing against high pages as long
+ * as recvmsg and memset works on it
+ */
+ vmf->page = alloc_page(GFP_HIGHUSER);
+ if (!vmf->page)
+ return VM_FAULT_OOM;
+ pg_addr = kmap(vmf->page);
+ pos = vmf->pgoff << PAGE_SHIFT;
+
+ count = PAGE_SIZE;
+ /* what we can read in one go */
+ bufsize = NCP_SERVER(inode)->buffer_size;
+
+ already_read = 0;
+ if (ncp_make_open(inode, O_RDONLY) >= 0) {
+ while (already_read < count) {
+ int read_this_time;
+ int to_read;
+
+ to_read = bufsize - (pos % bufsize);
+
+ to_read = min_t(unsigned int, to_read, count - already_read);
+
+ if (ncp_read_kernel(NCP_SERVER(inode),
+ NCP_FINFO(inode)->file_handle,
+ pos, to_read,
+ pg_addr + already_read,
+ &read_this_time) != 0) {
+ read_this_time = 0;
+ }
+ pos += read_this_time;
+ already_read += read_this_time;
+
+ if (read_this_time < to_read) {
+ break;
+ }
+ }
+ ncp_inode_close(inode);
+
+ }
+
+ if (already_read < PAGE_SIZE)
+ memset(pg_addr + already_read, 0, PAGE_SIZE - already_read);
+ flush_dcache_page(vmf->page);
+ kunmap(vmf->page);
+
+ /*
+ * If I understand ncp_read_kernel() properly, the above always
+ * fetches from the network, here the analogue of disk.
+ * -- nyc
+ */
+ count_vm_event(PGMAJFAULT);
+ count_memcg_event_mm(vmf->vma->vm_mm, PGMAJFAULT);
+ return VM_FAULT_MAJOR;
+}
+
+static const struct vm_operations_struct ncp_file_mmap =
+{
+ .fault = ncp_file_mmap_fault,
+};
+
+
+/* This is used for a general mmap of a ncp file */
+int ncp_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct inode *inode = file_inode(file);
+
+ ncp_dbg(1, "called\n");
+
+ if (!ncp_conn_valid(NCP_SERVER(inode)))
+ return -EIO;
+
+ /* only PAGE_COW or read-only supported now */
+ if (vma->vm_flags & VM_SHARED)
+ return -EINVAL;
+ /* we do not support files bigger than 4GB... We eventually
+ supports just 4GB... */
+ if (vma_pages(vma) + vma->vm_pgoff
+ > (1U << (32 - PAGE_SHIFT)))
+ return -EFBIG;
+
+ vma->vm_ops = &ncp_file_mmap;
+ file_accessed(file);
+ return 0;
+}