Re: [Bug #12608] 2.6.29-rc powerpc G5 Xorg legacy_mem regression

From: Hugh Dickins
Date: Fri Feb 06 2009 - 19:51:15 EST


On Fri, 6 Feb 2009, Jesse Barnes wrote:
>
> Yeah that should work. I always hated this code (well most of X actually); we
> could probably clean up the logic a little. If this works I'll send it
> out to the Xorg list for review.

Yes, thanks for restructuring it, I was rather itching to do so.

With the one small change below which I think you'll approve,
your patch works for me on the G5 - but I've not tested it on
other (x86) machines which were already working.

Hugh

>
> --
> Jesse Barnes, Intel Open Source Technology Center
>
> diff --git a/hw/xfree86/os-support/bus/linuxPci.c b/hw/xfree86/os-support/bus/linuxPci.c
> index 263fd8f..fa0fc0a 100644
> --- a/hw/xfree86/os-support/bus/linuxPci.c
> +++ b/hw/xfree86/os-support/bus/linuxPci.c
> @@ -471,23 +471,18 @@ xf86MapDomainMemory(int ScreenNum, int Flags, struct pci_device *dev,
> int fd = -1;
> pointer addr;
>
> - /*
> - * We use /proc/bus/pci on non-legacy addresses or if the Linux sysfs
> - * legacy_mem interface is unavailable.
> - */
> - if ((Base > 1024*1024) || ((fd = linuxOpenLegacy(dev, "legacy_mem")) < 0))
> - return linuxMapPci(ScreenNum, Flags, dev, Base, Size,
> - PCIIOC_MMAP_IS_MEM);
> - else
> - addr = mmap(NULL, Size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, Base);
> -
> - if (fd >= 0)
> - close(fd);
> - if (addr == NULL || addr == MAP_FAILED) {
> - perror("mmap failure");
> - FatalError("xf86MapDomainMem(): mmap() failure\n");
> + if (Base <= 1024*1024) {
> + /* Try legacy_mem (may not be available or implemented) */
> + if ((fd = linuxOpenLegacy(dev, "legacy_mem")) < 0) {

>=

> + addr = mmap(NULL, Size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, Base);
> + close(fd);
> + if (addr && addr != MAP_FAILED)
> + return addr;
> + }
> }
> - return addr;
> +
> + /* Fall back to old method if legacy_mem fails or Base >= 1M */
> + return linuxMapPci(ScreenNum, Flags, dev, Base, Size, PCIIOC_MMAP_IS_MEM);
> }
>
> /**
--
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