On Tue, May 03, 2016 at 02:55:17PM +0200, Andrew Jones wrote:
> On Tue, May 03, 2016 at 01:48:11PM +0200, Alexander Gordeev wrote:
> > Cc: Andrew Jones <drjones@xxxxxxxxxx>
> > Cc: Thomas Huth <thuth@xxxxxxxxxx>
> > Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
> > Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxx>
> > ---
> > lib/x86/asm/io.h | 2 ++
> > lib/x86/io.c | 10 ++++++++++
> > x86/vmexit.c | 10 ++--------
> > 3 files changed, 14 insertions(+), 8 deletions(-)
> >
> > diff --git a/lib/x86/asm/io.h b/lib/x86/asm/io.h
> > index 83387b5..2436822 100644
> > --- a/lib/x86/asm/io.h
> > +++ b/lib/x86/asm/io.h
> > @@ -49,4 +49,6 @@ static inline void *phys_to_virt(unsigned long phys)
> > return (void *)phys;
> > }
> >
> > +void __iomem *ioremap(phys_addr_t phys_addr, size_t size);
> > +
> > #endif
> > diff --git a/lib/x86/io.c b/lib/x86/io.c
> > index d396d42..f106842 100644
> > --- a/lib/x86/io.c
> > +++ b/lib/x86/io.c
> > @@ -1,6 +1,8 @@
> > #include "libcflat.h"
> > +#include "vm.h"
> > #include "smp.h"
> > #include "asm/io.h"
> > +#include "asm/page.h"
> > #ifndef USE_SERIAL
> > #define USE_SERIAL
> > #endif
> > @@ -81,3 +83,11 @@ void exit(int code)
> > asm volatile("out %0, %1" : : "a"(code), "d"((short)0xf4));
> > #endif
> > }
> > +
> > +void __iomem *ioremap(phys_addr_t phys_addr, size_t size)
> > +{
> > + phys_addr_t base = phys_addr & PAGE_MASK;
> > + phys_addr_t offset = phys_addr - base;
> > +
> > + return vmap(phys_addr, size) + offset;
>
> yeah, vmap is the way to go! Now, one missing thing, but it wasn't
> in x86/vmexit's implementation either. The kernel sets the PTEs
> for an ioremap with PCD, page cache disabled. I guess we can live
> without that in kvm-unit-tests, but it would make sense that I/O
> mappings would be uncached - and may help us find bugs when we
> properly map that way. (Note, ARM gets away with just using
> asm-generic's ioremap, because it uses an identity map for the page
> tables and all I/O is in a single range which is mapped as uncached)
I would say, the above is better to put in the changelog for this patch,
huh?
> > +}
> > diff --git a/x86/vmexit.c b/x86/vmexit.c
> > index db7dbd8..c2e1e49 100644
> > --- a/x86/vmexit.c
> > +++ b/x86/vmexit.c
> > @@ -371,8 +371,7 @@ int main(int ac, char **av)
> > {
> > struct fadt_descriptor_rev1 *fadt;
> > int i;
> > - unsigned long membar = 0, base, offset;
> > - void *m;
> > + unsigned long membar = 0;
> > pcidevaddr_t pcidev;
> >
> > smp_init();
> > @@ -394,12 +393,7 @@ int main(int ac, char **av)
> > }
> > if (pci_bar_is_memory(pcidev, i)) {
> > membar = pci_bar_addr(pcidev, i);
> > - base = membar & ~4095;
> > - offset = membar - base;
> > - m = alloc_vpages(1);
> > -
> > - install_page((void *)read_cr3(), base, m);
> > - pci_test.memaddr = m + offset;
> > + pci_test.memaddr = ioremap(membar, PAGE_SIZE);
> > } else {
> > pci_test.iobar = pci_bar_addr(pcidev, i);
> > }
> > --
> > 1.8.3.1
> >
>
> Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
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