Re: [PATCH v4 16/30] xen/riscv: introduce p2m.h

[Oleksii <oleksii.kurochko@xxxxxxxxx>]

On Mon, 2024-02-12 at 16:16 +0100, Jan Beulich wrote:
> On 05.02.2024 16:32, Oleksii Kurochko wrote:
> > Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
> 
> Acked-by: Jan Beulich <jbeulich@xxxxxxxx>
> with two more nits:
> 
> > --- /dev/null
> > +++ b/xen/arch/riscv/include/asm/p2m.h
> > @@ -0,0 +1,102 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +#ifndef __ASM_RISCV_P2M_H__
> > +#define __ASM_RISCV_P2M_H__
> > +
> > +#include <asm/page-bits.h>
> > +
> > +#define paddr_bits PADDR_BITS
> > +
> > +/*
> > + * List of possible type for each page in the p2m entry.
> > + * The number of available bit per page in the pte for this
> > purpose is 2 bits.
> > + * So it's possible to only have 4 fields. If we run out of value
> > in the
> > + * future, it's possible to use higher value for pseudo-type and
> > don't store
> > + * them in the p2m entry.
> > + */
> > +typedef enum {
> > +    p2m_invalid = 0,    /* Nothing mapped here */
> > +    p2m_ram_rw,         /* Normal read/write domain RAM */
> > +} p2m_type_t;
> > +
> > +#include <xen/p2m-common.h>
> > +
> > +static inline int get_page_and_type(struct page_info *page,
> > +                                    struct domain *domain,
> > +                                    unsigned long type)
> > +{
> > +    BUG_ON("unimplemented");
> > +    return -EINVAL;
> > +}
> > +
> > +/* Look up a GFN and take a reference count on the backing page.
> > */
> > +typedef unsigned int p2m_query_t;
> > +#define P2M_ALLOC    (1u<<0)   /* Populate PoD and paged-out
> > entries */
> > +#define P2M_UNSHARE  (1u<<1)   /* Break CoW sharing */
> > +
> > +static inline struct page_info *get_page_from_gfn(
> > +    struct domain *d, unsigned long gfn, p2m_type_t *t,
> > p2m_query_t q)
> > +{
> > +    BUG_ON("unimplemented");
> > +    return NULL;
> > +}
> > +
> > +static inline void memory_type_changed(struct domain *d)
> > +{
> > +    BUG_ON("unimplemented");
> > +}
> > +
> > +
> > +static inline int guest_physmap_mark_populate_on_demand(struct
> > domain *d, unsigned long gfn,
> 
> This line looks to be too long.
> 
> > +                                                        unsigned
> > int order)
> > +{
> > +    return -EOPNOTSUPP;
> > +}
> > +
> > +static inline int guest_physmap_add_entry(struct domain *d,
> > +                            gfn_t gfn,
> > +                            mfn_t mfn,
> > +                            unsigned long page_order,
> > +                            p2m_type_t t)
> 
> Indentation isn't quite right here.
> 
> I'll see about dealing with those while committing.
Thanks a lot.

~ Oleksii