Re: [Xen-devel] [RFC][v3][PATCH 5/6] tools:libxc: check if mmio BAR is out of RMRR mappings

["Chen, Tiejun" <tiejun.chen@xxxxxxxxx>]

On 2014/8/15 20:21, Andrew Cooper wrote:
> On 15/08/14 09:27, Tiejun Chen wrote:
> > We need to avoid allocating MMIO BAR conflicting to RMRR range.
> >
> > Signed-off-by: Tiejun Chen <tiejun.chen@xxxxxxxxx>
> > ---
> >   tools/libxc/xc_domain.c        | 26 ++++++++++++++++++++++++++
> >   tools/libxc/xc_hvm_build_x86.c | 23 +++++++++++++++++++++++
> >   tools/libxc/xenctrl.h          |  4 ++++
> >   3 files changed, 53 insertions(+)
> >
> > diff --git a/tools/libxc/xc_domain.c b/tools/libxc/xc_domain.c
> > index c67ac9a..8d011ef 100644
> > --- a/tools/libxc/xc_domain.c
> > +++ b/tools/libxc/xc_domain.c
> > @@ -649,6 +649,32 @@ int xc_domain_set_memory_map(xc_interface *xch,
> >
> >       return rc;
> >   }
> > +
> > +int xc_get_rmrr_map(xc_interface *xch,
> This function name should match the hypercall.  Perhaps
> xc_reserved_device_memory_map() ?
Okay.

> > +                    struct e820entry entries[],
> > +                    uint32_t max_entries)
> This libxc function would be far more use if it took a single
> xen_memory_map parameter, rather than splitting the return information
> from Xen between one of the parameters and the return value.
I can't understand why we do something specific here. Please take a look 
at xc_get_machine_memory_map(). So why did you think we should do this?
Thanks
Tiejun

> ~Andrew
>
> > +{
> > +    int rc;
> > +    struct xen_memory_map memmap = {
> > +        .nr_entries = max_entries
> > +    };
> > +    DECLARE_HYPERCALL_BOUNCE(entries, sizeof(struct e820entry) * max_entries,
> > +                             XC_HYPERCALL_BUFFER_BOUNCE_OUT);
> > +
> > +    if ( !entries || xc_hypercall_bounce_pre(xch, entries) || max_entries <= 1)
> > +        return -1;
> > +
> > +
> > +    set_xen_guest_handle(memmap.buffer, entries);
> > +
> > +    rc = do_memory_op(xch, XENMEM_reserved_device_memory_map,
> > +                      &memmap, sizeof(memmap));
> > +
> > +    xc_hypercall_bounce_post(xch, entries);
> > +
> > +    return rc ? rc : memmap.nr_entries;
> > +}
> > +
> >   int xc_get_machine_memory_map(xc_interface *xch,
> >                                 struct e820entry entries[],
> >                                 uint32_t max_entries)
> > diff --git a/tools/libxc/xc_hvm_build_x86.c b/tools/libxc/xc_hvm_build_x86.c
> > index c81a25b..2196cdb 100644
> > --- a/tools/libxc/xc_hvm_build_x86.c
> > +++ b/tools/libxc/xc_hvm_build_x86.c
> > @@ -262,6 +262,8 @@ static int setup_guest(xc_interface *xch,
> >       int claim_enabled = args->claim_enabled;
> >       xen_pfn_t special_array[NR_SPECIAL_PAGES];
> >       xen_pfn_t ioreq_server_array[NR_IOREQ_SERVER_PAGES];
> > +    struct e820entry map[E820MAX];
> > +    uint64_t rmrr_start = 0, rmrr_end = 0;
> >
> >       if ( nr_pages > target_pages )
> >           pod_mode = XENMEMF_populate_on_demand;
> > @@ -300,6 +302,27 @@ static int setup_guest(xc_interface *xch,
> >           goto error_out;
> >       }
> >
> > +    /* We should check if mmio range is out of RMRR mapping. */
> > +    rc = xc_get_rmrr_map(xch, map, E820MAX);
> > +    if (rc < 0)
> > +    {
> > +        PERROR("Could not get RMRR info on domain");
> > +    }
> > +    else if ( rc )
> > +    {
> > +        for ( i = 0; i < rc; i++ )
> > +        {
> > +            rmrr_start = map[i].addr;
> > +            rmrr_end = map[i].addr + map[i].size + 1;
> > +            if ( check_mmio_hole(rmrr_start, map[i].size + 1, mmio_start, 
> > mmio_size) )
> > +            {
> > +                PERROR("MMIO: [%lx]<->[%lx] overlap RMRR [%lx]<->[%lx]\n",
> > +                       mmio_start, (mmio_start + mmio_size), rmrr_start, 
> > rmrr_end);
> > +                goto error_out;
> > +            }
> > +        }
> > +    }
> > +
> >       for ( i = 0; i < nr_pages; i++ )
> >           page_array[i] = i;
> >       for ( i = mmio_start >> PAGE_SHIFT; i < nr_pages; i++ )
> > diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
> > index 1c5d0db..6d3b135 100644
> > --- a/tools/libxc/xenctrl.h
> > +++ b/tools/libxc/xenctrl.h
> > @@ -1270,6 +1270,10 @@ int xc_domain_set_memory_map(xc_interface *xch,
> >   int xc_get_machine_memory_map(xc_interface *xch,
> >                                 struct e820entry entries[],
> >                                 uint32_t max_entries);
> > +
> > +int xc_get_rmrr_map(xc_interface *xch,
> > +                    struct e820entry entries[],
> > +                    uint32_t max_entries);
> >   #endif
> >   int xc_domain_set_time_offset(xc_interface *xch,
> >                                 uint32_t domid,
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel