Messages in this thread | | | Date | Tue, 31 Jan 2012 11:32:50 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH v3] fs: Invalidate the cache for a parent block-device if fsync() is called for a partition |
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On Tue, 31 Jan 2012 14:04:25 -0500 Christoph Hellwig <hch@infradead.org> wrote:
> On Tue, Jan 31, 2012 at 10:58:24AM -0800, Andrew Morton wrote: > > One concern I have with the proposal is that it would forever rule out > > support of >16T devices on 32-bit machines. > > > > At present with 64-bit sector_t and 32-bit pgoff_t, I think we'd have a > > reasonable chance of supporting, say, four 8T partitions on a 32T > > device. But if we were to switch the kernel from using four 4T > > address_spaces (sda1-4) over to using a single 32T address_space (sda) > > then we can rule it all out. > > how do you plan to write the partition label in your hypothetic setup > if you can't open the main device? > > And even if we solved that and people could create partitions on these > devices but not open the main device, or use large lvm volumes it would > be an absolutely major confusion. >
I didn't say the kernel would support this as-is.
If the partitioning scheme requires writing to the individual partitions then something would need to be done, such as a simple offsetting DM driver.
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