Messages in this thread | | | Date | Thu, 7 May 2015 09:03:27 -0700 | Subject | Re: [PATCH v2 00/10] evacuate struct page from the block layer, introduce __pfn_t | From | Dan Williams <> |
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On Thu, May 7, 2015 at 8:58 AM, Linus Torvalds <torvalds@linux-foundation.org> wrote: > On Thu, May 7, 2015 at 8:40 AM, Dan Williams <dan.j.williams@intel.com> wrote: >> >> blkdev_get(FMODE_EXCL) is the protection in this case. > > Ugh. That looks like a horrible nasty big hammer that will bite us > badly some day. Since you'd have to hold it for the whole IO. But I > guess it at least works.
Oh no, that wouldn't be per-I/O that would be permanent at configuration set up time just like a raid member device.
Something like: mdadm --create /dev/md0 --cache=/dev/pmem0p1 --storage=/dev/sda
> Anyway, I did want to say that while I may not be convinced about the > approach, I think the patches themselves don't look horrible. I > actually like your "__pfn_t". So while I (very obviously) have some > doubts about this approach, it may be that the most convincing > argument is just in the code.
Ok, I'll keep thinking about this and come back when we have a better story about passing mmap'd persistent memory around in userspace.
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