On Mon, 21 Mar 2005 13:33:55 -0800, Bryan Henderson <[EMAIL PROTECTED]> wrote: > >I want all my file system's operations to be complete uncached and > >synchronous, but I also want to support mmap. > >... > >What am I doing wrong? Is what I'm trying to do impossible, and if > >so, how can I get as close as possible? > > It looks to me like you're running into the fundamental limitation that > the CPU doesn't notify Linux every time you store into a memory location. > It does, though, set the dirty flag in the page table, and Linux > eventually inspects that flag and finds out that you have stored in the > past. At that time, it can call set_page_dirty. >
Is there an existing interface to force it to check if the page is dirty -- for example, one way to maintain coherency would be for my normal read/write path to check if the page is dirty and write it back and invalidate the page before executing the normal-path read/write. This may be an unlikely scenerio, but I think it is one of the corner cases fsx tickles. -eric - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html