[PATCH] IB/ehca: Make sure user pages are from hugetlb before using MR large pages
FENKES at de.ibm.com
Fri Sep 14 00:27:03 EST 2007
Roland Dreier <rdreier at cisco.com> wrote on 13.09.2007 06:33:45:
> > -#define HCA_CAP_MR_PGSIZE_4K 1
> > -#define HCA_CAP_MR_PGSIZE_64K 2
> > -#define HCA_CAP_MR_PGSIZE_1M 4
> > -#define HCA_CAP_MR_PGSIZE_16M 8
> > +#define HCA_CAP_MR_PGSIZE_4K 0x80000000
> > +#define HCA_CAP_MR_PGSIZE_64K 0x40000000
> > +#define HCA_CAP_MR_PGSIZE_1M 0x20000000
> > +#define HCA_CAP_MR_PGSIZE_16M 0x10000000
> Not sure I understand what this has to do with things... is this an
> unrelated fix?
Kinda. I can put it into its own patch if you want.
> I would suggest extending ib_umem_get() to check the vmas and adding a
> member to struct ib_umem to say whether the memory is entirely covered
> by hugetlb pages or not.
I like that approach - one patch coming right up! =)
> > + default: /* out of mem */
> > + ib_mr = ERR_PTR(-ENOMEM);
> > + goto reg_user_mr_exit1;
> It seems like it would be better to just assume the memory is not from
> a hugetlb is ehca_is_mem_hugetlb() fails its memory allocation and
> fall back to the PAGE_SIZE case rather than failing entirely.
If ehca_is_mem_hugetlb() runs out of memory, ehca_reg_mr() is rather
unlikely to get the memory, but it's worth a try, I'll give you that. I'll
make the umem patch work that way.
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