From mboxrd@z Thu Jan  1 00:00:00 1970
From: Charles Manning <manningc2@actrix.gen.nz>
Subject: Is naked reading of inode->i_size OK?
Date: Wed, 10 Oct 2007 12:40:08 +1300
Message-ID: <200710101240.08069.manningc2@actrix.gen.nz>
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Reading through 2.6.23's vmtruncate() [mm/memory.c], I notice that vmtruncate 
reads inode->i_size directly and not through the i_size_read() wrapper. Is 
that OK?

Lower down the same function calls i_size_write() and the calling chain calls 
i_size_read() so why is i_size_read() not being used here?

int vmtruncate(struct inode * inode, loff_t offset)
{
        struct address_space *mapping = inode->i_mapping;
        unsigned long limit;

        if (inode->i_size < offset)
                goto do_expand;
 	...
}