search for: 4c3b80e68121

...ic struct page *dax_busy_page(void *entry) for_each_mapped_pfn(entry, pfn) { struct page *page = pfn_to_page(pfn); - if (page_ref_count(page) > 1) + if (!dax_layout_is_idle_page(page)) return page; } return NULL; diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index bf596467c234..4c3b80e68121 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3926,10 +3926,7 @@ int ext4_break_layouts(struct inode *inode) if (!page) return 0; - error = ___wait_var_event(&page->_refcount, - atomic_read(&page->_refcount) == 1, - TASK_INTERRUPTIBLE, 0, 0, - ext4_wait_dax...

This is still an RFC because after looking at the pmem/dax code some more, I realized that the ZONE_DEVICE struct pages are being inserted into the process' page tables with vmf_insert_mixed() and a zero refcount on the ZONE_DEVICE struct page. This is sort of OK because insert_pfn() increments the reference count on the pgmap which is what prevents memunmap_pages() from freeing the struct