> -----Original Message----- > From: Jan Beulich [mailto:jbeul...@suse.com] > Sent: 17 October 2017 10:06 > To: Paul Durrant <paul.durr...@citrix.com> > Cc: Andrew Cooper <andrew.coop...@citrix.com>; George Dunlap > <george.dun...@citrix.com>; Ian Jackson <ian.jack...@citrix.com>; Wei Liu > <wei.l...@citrix.com>; sstabell...@kernel.org; xen- > de...@lists.xenproject.org; konrad.w...@oracle.com; Tim (Xen.org) > <t...@xen.org> > Subject: RE: [PATCH v11 10/11] common: add a new mappable resource type: > XENMEM_resource_grant_table > > >>> On 17.10.17 at 10:30, <paul.durr...@citrix.com> wrote: > >> From: Jan Beulich [mailto:jbeul...@suse.com] > >> Sent: 17 October 2017 07:43 > >> >>> Paul Durrant <paul.durr...@citrix.com> 10/12/17 6:28 PM >>> > >> >+int gnttab_get_grant_frame(struct domain *d, unsigned long idx, > >> >+ mfn_t *mfn) > >> >+{ > >> >+ struct grant_table *gt = d->grant_table; > >> >+ int rc; > >> >+ > >> >+ /* write lock required as version may change and/or table may grow > */ > >> >+ grant_write_lock(gt); > >> >+ > >> >+ rc = (gt->gt_version == 2 && > >> >+ idx > XENMAPIDX_grant_table_status) ? > >> > >> I don't understand this check - why does XENMAPIDX_grant_table_status > >> matter here at all? Same in gnttab_get_status_frame() then. > >> > > > > Well, the current legal range of grant table frames for v2 is 0 - (1 << > > XENMAPIDX_grant_table_status) whereas it appears that for v1 there is no > > limit. As for status frames, they are a v2-only concept but I agree that the > > range check there is wrong. > > I don't think the range limitation from the other interface should > impose any restriction for this new one.
Ok. I'll drop the check. > > Oh, one other thing I only notice now - could you please also > attach a brief comment to the array that you grow to 32 > entries making clear that this is a pretty arbitrary choice? > Sure. Paul > Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
