From cedabed49b39b4319bccc059a63344b6232b619c Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Wed, 13 Jan 2010 21:14:09 +0900 Subject: [PATCH] vfs: Fix vmtruncate() regression If __block_prepare_write() was failed in block_write_begin(), the allocated blocks can be outside of ->i_size. But new truncate_pagecache() in vmtuncate() does nothing if new < old. It means the above usage is not working anymore. So, this patch fixes it by removing "new < old" check. It would need more cleanup/change. But, now -rc and truncate working is in progress, so, this tried to fix it minimum change. Acked-by: Nick Piggin Signed-off-by: OGAWA Hirofumi Signed-off-by: Linus Torvalds --- mm/truncate.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/mm/truncate.c b/mm/truncate.c index 342deee22684..e87e37244829 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -522,22 +522,20 @@ EXPORT_SYMBOL_GPL(invalidate_inode_pages2); */ void truncate_pagecache(struct inode *inode, loff_t old, loff_t new) { - if (new < old) { - struct address_space *mapping = inode->i_mapping; - - /* - * unmap_mapping_range is called twice, first simply for - * efficiency so that truncate_inode_pages does fewer - * single-page unmaps. However after this first call, and - * before truncate_inode_pages finishes, it is possible for - * private pages to be COWed, which remain after - * truncate_inode_pages finishes, hence the second - * unmap_mapping_range call must be made for correctness. - */ - unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1); - truncate_inode_pages(mapping, new); - unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1); - } + struct address_space *mapping = inode->i_mapping; + + /* + * unmap_mapping_range is called twice, first simply for + * efficiency so that truncate_inode_pages does fewer + * single-page unmaps. However after this first call, and + * before truncate_inode_pages finishes, it is possible for + * private pages to be COWed, which remain after + * truncate_inode_pages finishes, hence the second + * unmap_mapping_range call must be made for correctness. + */ + unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1); + truncate_inode_pages(mapping, new); + unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1); } EXPORT_SYMBOL(truncate_pagecache); -- GitLab