Commit fc3a5ac5 authored by Matthew Wilcox (Oracle)'s avatar Matthew Wilcox (Oracle) Committed by Linus Torvalds
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mm/truncate: fix truncation for pages of arbitrary size 



Remove the assumption that a compound page is HPAGE_PMD_SIZE, and the
assumption that any page is PAGE_SIZE.

Signed-off-by: default avatarMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: default avatarSeongJae Park <sjpark@amazon.de>
Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Link: https://lkml.kernel.org/r/20200908195539.25896-10-willy@infradead.org


Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5eaf35ab

mm/truncate.c

+3 −3
Original line number Diff line number Diff line
@@ -168,7 +168,7 @@ void do_invalidatepage(struct page *page, unsigned int offset, 
 * becomes orphaned.  It will be left on the LRU and may even be mapped into

 * user pagetables if we're racing with filemap_fault().

 *

 * We need to bale out if page->mapping is no longer equal to the original

 * We need to bail out if page->mapping is no longer equal to the original

 * mapping.  This happens a) when the VM reclaimed the page while we waited on

 * its lock, b) when a concurrent invalidate_mapping_pages got there first and

 * c) when tmpfs swizzles a page between a tmpfs inode and swapper_space.
@@ -177,12 +177,12 @@ static void 
truncate_cleanup_page(struct address_space *mapping, struct page *page)

{

	if (page_mapped(page)) {

		pgoff_t nr = PageTransHuge(page) ? HPAGE_PMD_NR : 1;

		unsigned int nr = thp_nr_pages(page);

		unmap_mapping_pages(mapping, page->index, nr, false);

	}



	if (page_has_private(page))

		do_invalidatepage(page, 0, PAGE_SIZE);

		do_invalidatepage(page, 0, thp_size(page));



	/*

	 * Some filesystems seem to re-dirty the page even after