Re: [PATCH 1/4] xen/acpi: Rework acpi_os_map_memory() and acpi_os_unmap_memory()

[Julien Grall <julien@xxxxxxx>]

Hi Stefano,

On 01/10/2020 01:06, Stefano Stabellini wrote:
> On Sat, 26 Sep 2020, Julien Grall wrote:
> > From: Julien Grall <jgrall@xxxxxxxxxx>
> >
> > The functions acpi_os_{un,}map_memory() are meant to be arch-agnostic
> > while the __acpi_os_{un,}map_memory() are meant to be arch-specific.
> >
> > Currently, the former are still containing x86 specific code.
> >
> > To avoid this rather strange split, the generic helpers are reworked so
> > they are arch-agnostic. This requires the introduction of a new helper
> > __acpi_os_unmap_memory() that will undo any mapping done by
> > __acpi_os_map_memory().
> >
> > Currently, the arch-helper for unmap is basically a no-op so it only
> > returns whether the mapping was arch specific. But this will change
> > in the future.
> >
> > Note that the x86 version of acpi_os_map_memory() was already able to
> > able the 1MB region. Hence why there is no addition of new code.
> >
> > Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx>
> > ---
> >   xen/arch/arm/acpi/lib.c | 10 ++++++++++
> >   xen/arch/x86/acpi/lib.c | 18 ++++++++++++++++++
> >   xen/drivers/acpi/osl.c  | 34 ++++++++++++++++++----------------
> >   xen/include/xen/acpi.h  |  1 +
> >   4 files changed, 47 insertions(+), 16 deletions(-)
> >
> > diff --git a/xen/arch/arm/acpi/lib.c b/xen/arch/arm/acpi/lib.c
> > index 4fc6e17322c1..2192a5519171 100644
> > --- a/xen/arch/arm/acpi/lib.c
> > +++ b/xen/arch/arm/acpi/lib.c
> > @@ -30,6 +30,10 @@ char *__acpi_map_table(paddr_t phys, unsigned long size)
> >       unsigned long base, offset, mapped_size;
> >       int idx;
> >   
> > +    /* No arch specific implementation after early boot */
> > +    if ( system_state >= SYS_STATE_boot )
> > +        return NULL;
> > +
> >       offset = phys & (PAGE_SIZE - 1);
> >       mapped_size = PAGE_SIZE - offset;
> >       set_fixmap(FIXMAP_ACPI_BEGIN, maddr_to_mfn(phys), PAGE_HYPERVISOR);
> > @@ -49,6 +53,12 @@ char *__acpi_map_table(paddr_t phys, unsigned long size)
> >       return ((char *) base + offset);
> >   }
> >   
> > +bool __acpi_unmap_table(void *ptr, unsigned long size)
> > +{
> > +    return ( vaddr >= FIXMAP_ADDR(FIXMAP_ACPI_BEGIN) &&
> > +             vaddr < (FIXMAP_ADDR(FIXMAP_ACPI_END) + PAGE_SIZE) );
> > +}
> vaddr or ptr?  :-)
>
> lib.c: In function '__acpi_unmap_table':
> lib.c:58:14: error: 'vaddr' undeclared (first use in this function)
>       return ( vaddr >= FIXMAP_ADDR(FIXMAP_ACPI_BEGIN) &&
>                ^
> lib.c:58:14: note: each undeclared identifier is reported only once for each 
> function it appears in
> lib.c:60:1: error: control reaches end of non-void function 
> [-Werror=return-type]
>   }
>   ^
> cc1: all warnings being treated as errors
The whole series builds because 'vaddr' is added in the next patch. But 
I forgot to build patch by patch :(.
I will fix it in the next version.

Cheers,

--
Julien Grall