Hi Linus,

On 22 Sep 2014, at 16:18, Linus Torvalds [off-list ref] wrote:

On Sun, Sep 21, 2014 at 5:53 PM, Anton Altaparmakov [off-list ref] wrote:

quoted

This patch fixes this issue by type casting "index" to sector_t before
doing the left shift.

Ugh. Does the simpler patch to just pass in "block" work as well?

That doesn't work because nothing rounds down "block" to the first block in the page and init_page_buffers() requires "block" to be the first block in the page.

The shift right followed by shift left achieves the "rounding down" required.

You could do "block & ~(sector_t)(size - 1)" instead of "(sector_t)index << sizebits" if you prefer but not sure that is an improvement!

Best regards,

	Anton

                   Linus
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Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @)
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