diff mbox series

[16/35] dmemfs: introduce ->split() to dmemfs_vm_ops

Message ID adb685974526804279d5c40f183985a9a5005d43.1602093760.git.yuleixzhang@tencent.com (mailing list archive)
State New, archived
Headers show
Series Enhance memory utilization with DMEMFS | expand

Commit Message

yulei zhang Oct. 8, 2020, 7:54 a.m. UTC 
From: Yulei Zhang <yuleixzhang@tencent.com>

It is required by __split_vma() to adjust vma. munmap() which create
hole unaligned to pagesize in dmemfs-mapping should be forbidden.

Signed-off-by: Chen Zhuo <sagazchen@tencent.com>
Signed-off-by: Yulei Zhang <yuleixzhang@tencent.com>
---
 fs/dmemfs/inode.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/fs/dmemfs/inode.c b/fs/dmemfs/inode.c
index 6932d73edab6..e37498c00497 100644
--- a/fs/dmemfs/inode.c
+++ b/fs/dmemfs/inode.c
@@ -453,6 +453,13 @@  dmemfs_access_dmem(struct vm_area_struct *vma, unsigned long addr,
 	return len;
 }
 
+static int dmemfs_split(struct vm_area_struct *vma, unsigned long addr)
+{
+	if (addr & (dmem_page_size(file_inode(vma->vm_file)) - 1))
+		return -EINVAL;
+	return 0;
+}
+
 static vm_fault_t dmemfs_fault(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;
@@ -487,6 +494,7 @@  static unsigned long dmemfs_pagesize(struct vm_area_struct *vma)
 }
 
 static const struct vm_operations_struct dmemfs_vm_ops = {
+	.split = dmemfs_split,
 	.fault = dmemfs_fault,
 	.pagesize = dmemfs_pagesize,
 	.access = dmemfs_access_dmem,