On Thu, Nov 12, 2009 at 10:12:07PM +0900, Isaku Yamahata wrote: > On Thu, Nov 12, 2009 at 02:06:22PM +0200, Michael S. Tsirkin wrote: > > On Thu, Nov 12, 2009 at 02:58:44PM +0900, Isaku Yamahata wrote: > > > This patch kills nasty goto in pci_update_mappings(). > > > > > > Signed-off-by: Isaku Yamahata <yamah...@valinux.co.jp> > > > --- > > > hw/pci.c | 54 ++++++++++++++++++++++++++++-------------------------- > > > 1 files changed, 28 insertions(+), 26 deletions(-) > > > > > > diff --git a/hw/pci.c b/hw/pci.c > > > index cae3d53..2eff7fe 100644 > > > --- a/hw/pci.c > > > +++ b/hw/pci.c > > > @@ -756,35 +756,37 @@ static void pci_update_mappings(PCIDevice *d) > > > new_addr = pci_get_long(d->config + pci_bar(d, i)); > > > } > > > /* the ROM slot has a specific enable bit */ > > > - if (i == PCI_ROM_SLOT && !(new_addr & > > > PCI_ROM_ADDRESS_ENABLE)) > > > - goto no_mem_map; > > > - new_addr = new_addr & ~(r->size - 1); > > > - last_addr = new_addr + r->size - 1; > > > - /* NOTE: we do not support wrapping */ > > > - /* XXX: as we cannot support really dynamic > > > - mappings, we handle specific values as invalid > > > - mappings. */ > > > - if (last_addr <= new_addr || new_addr == 0 || > > > > By the way, any idea why do we need new_addr == 0 > > and last_addr == PCI_BAR_UNMAPPED? > > As for new_addr == 0, since default BAR value is zero, plural BARs can > overlap with each other. I think qemu can't handle BAR overlap anyway. > > As for last_addr == PCI_BAR_UNMAPPED, it avoid to map > around 4GB as discussed before.
So it should be ~0x0ull and not PCI_BAR_UNMAPPED, PCI_BAR_UNMAPPED could be any value e.g. 0x1 would do as well. > I observed that guest doesn't boot > without the check. However I didn't track it down further. > Now it's 64bit though. I really think we need to move mapping regions out of devices and into pci.c. Then we can finally support overlapping BARs (by being careful not to map common regions). -- MST
