Now that iput_final() arranges for dax_break_layouts(), all
truncate_inode_pages() paths in the kernel ensure that no DAX pages
hosted by that inode are in use. Add warnings to assert the new entry
state transitions.
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: "Darrick J. Wong" <djwong@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: John Hubbard <jhubbard@xxxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
fs/dax.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index e3deb60a792f..1d4f0072e58d 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -401,13 +401,15 @@ static void dax_disassociate_entry(void *entry, struct address_space *mapping,
for_each_mapped_pfn(entry, pfn) {
struct page *page = pfn_to_page(pfn);
- WARN_ON_ONCE(trunc && !dax_page_idle(page));
if (dax_mapping_is_cow(page->mapping)) {
/* keep the CoW flag if this page is still shared */
if (page->index-- > 0)
continue;
- } else
+ } else {
+ WARN_ON_ONCE(trunc && !dax_is_zapped(entry));
+ WARN_ON_ONCE(trunc && !dax_page_idle(page));
WARN_ON_ONCE(page->mapping && page->mapping != mapping);
+ }
page->mapping = NULL;
page->index = 0;
}
