[PATCH RFC 07/10] fs/ext4: Fail truncate if pages are GUP pinned

ira.weiny
2019-06-06T01:45:21Z

From: Ira Weiny <ira.weiny@intel.com>

If pages are actively gup pinned fail the truncate operation.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
---
fs/ext4/inode.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 75f543f384e4..1ded83ec08c0 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4250,6 +4250,9 @@ int ext4_break_layouts(struct inode *inode, loff_t offset, loff_t len)
if (!page)
return 0;

+ if (page_gup_pinned(page))
+ return -ETXTBSY;
+
error = ___wait_var_event(&page->_refcount,
atomic_read(&page->_refcount) == 1,
TASK_INTERRUPTIBLE, 0, 0,
--
2.20.1