From 0056e65f9e28d83ee1a3fb4f7d0041e838f03c34 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Wed, 30 Jul 2008 14:26:25 -0700 Subject: [PATCH] romfs_readpage: don't report errors for pages beyond i_size We zero-fill them like we are supposed to, and that's all fine. It's only an error if the 'romfs_copyfrom()' routine isn't able to fill the data that is supposed to be there. Most of the patch is really just re-organizing the code a bit, and using separate variables for the error value and for how much of the page we actually filled from the filesystem. Reported-and-tested-by: Chris Fester Cc: Alexander Viro Cc: Matt Waddel Cc: Greg Ungerer Signed-of-by: Linus Torvalds --- fs/romfs/inode.c | 37 +++++++++++++++++++++++-------------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/fs/romfs/inode.c b/fs/romfs/inode.c index 8e51a2aaa9..60d2f822e8 100644 --- a/fs/romfs/inode.c +++ b/fs/romfs/inode.c @@ -418,7 +418,8 @@ static int romfs_readpage(struct file *file, struct page * page) { struct inode *inode = page->mapping->host; - loff_t offset, avail, readlen; + loff_t offset, size; + unsigned long filled; void *buf; int result = -EIO; @@ -430,21 +431,29 @@ romfs_readpage(struct file *file, struct page * page) /* 32 bit warning -- but not for us :) */ offset = page_offset(page); - if (offset < i_size_read(inode)) { - avail = inode->i_size-offset; - readlen = min_t(unsigned long, avail, PAGE_SIZE); - if (romfs_copyfrom(inode, buf, ROMFS_I(inode)->i_dataoffset+offset, readlen) == readlen) { - if (readlen < PAGE_SIZE) { - memset(buf + readlen,0,PAGE_SIZE-readlen); - } - SetPageUptodate(page); - result = 0; + size = i_size_read(inode); + filled = 0; + result = 0; + if (offset < size) { + unsigned long readlen; + + size -= offset; + readlen = size > PAGE_SIZE ? PAGE_SIZE : size; + + filled = romfs_copyfrom(inode, buf, ROMFS_I(inode)->i_dataoffset+offset, readlen); + + if (filled != readlen) { + SetPageError(page); + filled = 0; + result = -EIO; } } - if (result) { - memset(buf, 0, PAGE_SIZE); - SetPageError(page); - } + + if (filled < PAGE_SIZE) + memset(buf + filled, 0, PAGE_SIZE-filled); + + if (!result) + SetPageUptodate(page); flush_dcache_page(page); unlock_page(page); -- 2.39.5