Re: [Xen-devel] [PATCH 11/38] arm: implement p2m lookup

[Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>]

On Fri, 1 Jun 2012, Ian Campbell wrote:
> Signed-off-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> ---
>  xen/arch/arm/p2m.c        |   71 ++++++++++++++++++++++++++++++++++++++++++--
>  xen/include/asm-arm/p2m.h |    3 ++
>  2 files changed, 70 insertions(+), 4 deletions(-)
> 
> diff --git a/xen/arch/arm/p2m.c b/xen/arch/arm/p2m.c
> index 095e608..9b40e93 100644
> --- a/xen/arch/arm/p2m.c
> +++ b/xen/arch/arm/p2m.c
> @@ -10,10 +10,20 @@ void dump_p2m_lookup(struct domain *d, paddr_t addr)
>      struct p2m_domain *p2m = &d->arch.p2m;
>      lpae_t *first = NULL, *second = NULL, *third = NULL;
>  
> -    printk("dom%d IPA %#016llx\n", d->domain_id, addr);
> +    printk("dom%d IPA %#"PRIpaddr"\n", d->domain_id, addr);
> +
> +    printk("P2M @ %p mfn:%#lx (%#03llx,%#03llx,%#03llx)\n",
> +           p2m->first_level,
> +           page_to_mfn(p2m->first_level),
> +           first_table_offset(addr),
> +           second_table_offset(addr),
> +           third_table_offset(addr));
> +
> +    if ( first_table_offset(addr) >= LPAE_ENTRIES )
> +        goto done;
>  
>      first = __map_domain_page(p2m->first_level);
> -    printk("1ST[%#03llx] = %#016llx\n",
> +    printk("1ST[%#03llx] = %#"PRIpaddr"\n",
>             first_table_offset(addr),
>             first[first_table_offset(addr)].bits);
>      if ( !first[first_table_offset(addr)].p2m.valid ||
> @@ -21,7 +31,7 @@ void dump_p2m_lookup(struct domain *d, paddr_t addr)
>          goto done;
>  
>      second = map_domain_page(first[first_table_offset(addr)].p2m.base);
> -    printk("2ND[%#03llx] = %#016llx\n",
> +    printk("2ND[%#03llx] = %#"PRIpaddr"\n",
>             second_table_offset(addr),
>             second[second_table_offset(addr)].bits);
>      if ( !second[second_table_offset(addr)].p2m.valid ||
> @@ -29,7 +39,7 @@ void dump_p2m_lookup(struct domain *d, paddr_t addr)
>          goto done;
>  
>      third = map_domain_page(second[second_table_offset(addr)].p2m.base);
> -    printk("3RD[%#03llx] = %#016llx\n",
> +    printk("3RD[%#03llx] = %#"PRIpaddr"\n",
>             third_table_offset(addr),
>             third[third_table_offset(addr)].bits);
>  
> @@ -51,6 +61,59 @@ void p2m_load_VTTBR(struct domain *d)
>      isb(); /* Ensure update is visible */
>  }

there is no need to introduce p2m_lookup in the same patch you do these
unrelated printk adjustments, correct?


> +/*
> + * Lookup the MFN corresponding to a domain's PFN.
> + *
> + * There are no processor functions to do a stage 2 only lookup therefore we
> + * do a a software walk.
> + */
> +paddr_t p2m_lookup(struct domain *d, paddr_t paddr)
> +{
> +    struct p2m_domain *p2m = &d->arch.p2m;
> +    lpae_t pte, *first = NULL, *second = NULL, *third = NULL;
> +    paddr_t maddr = INVALID_PADDR;
> +
> +    spin_lock(&p2m->lock);
> +
> +    first = __map_domain_page(p2m->first_level);
> +    if ( !first[first_table_offset(paddr)].p2m.valid )
> +        goto done_err;
> +    if ( !first[first_table_offset(paddr)].p2m.table )
> +    {
> +        pte = first[first_table_offset(paddr)];
> +        goto done;
> +    }
> +
> +    second = map_domain_page(first[first_table_offset(paddr)].p2m.base);
> +    if ( !second[second_table_offset(paddr)].p2m.valid )
> +        goto done_err;
> +    if ( !second[second_table_offset(paddr)].p2m.table )
> +    {
> +        pte = second[second_table_offset(paddr)];
> +        goto done;
> +    }
> +
> +    third = map_domain_page(second[second_table_offset(paddr)].p2m.base);
> +    if ( !third[third_table_offset(paddr)].p2m.valid )
> +        goto done_err;
> +    if ( !third[third_table_offset(paddr)].p2m.table )
> +        goto done_err;
> +
> +    pte = third[third_table_offset(paddr)];
> +
> +done:
> +
> +    maddr = (pte.bits & PADDR_MASK & PAGE_MASK) | (paddr & ~PAGE_MASK);
> +done_err:
> +    if (third) unmap_domain_page(third);
> +    if (second) unmap_domain_page(second);
> +    if (first) unmap_domain_page(first);
> +
> +    spin_unlock(&p2m->lock);
> +
> +    return maddr;
> +}
> +

this function looks correct though

>  int guest_physmap_mark_populate_on_demand(struct domain *d,
>                                            unsigned long gfn,
>                                            unsigned int order)
> diff --git a/xen/include/asm-arm/p2m.h b/xen/include/asm-arm/p2m.h
> index 349923a..1afd5cb 100644
> --- a/xen/include/asm-arm/p2m.h
> +++ b/xen/include/asm-arm/p2m.h
> @@ -32,6 +32,9 @@ int p2m_alloc_table(struct domain *d);
>  /* */
>  void p2m_load_VTTBR(struct domain *d);
>  
> +/* */
> +paddr_t p2m_lookup(struct domain *d, paddr_t gpfn);
> +
>  /* Setup p2m RAM mapping for domain d from start-end. */
>  int p2m_populate_ram(struct domain *d, paddr_t start, paddr_t end);
>  /* Map MMIO regions in the p2m: start_gaddr and end_gaddr is the range
> -- 
> 1.7.9.1
> 
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@xxxxxxxxxxxxx
> http://lists.xen.org/xen-devel
> 

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel