[PATCH v3 3/6] lib: sbi: Add sbi_domain_check_addr_range() function

[Bin Meng]

On Wed, Dec 21, 2022 at 5:30 PM Bin Meng <bmeng.cn at gmail.com> wrote:
>
> On Thu, Nov 24, 2022 at 9:32 PM Anup Patel <apatel at ventanamicro.com> wrote:
> >
> > We add sbi_domain_check_addr_range() helper function to check
> > whether a given address range is accessible under a particular
> > domain.
> >
> > Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> > ---
> >  include/sbi/sbi_domain.h | 15 +++++++++
> >  lib/sbi/sbi_domain.c     | 69 ++++++++++++++++++++++++++++++++++++++++
> >  2 files changed, 84 insertions(+)
> >
> > diff --git a/include/sbi/sbi_domain.h b/include/sbi/sbi_domain.h
> > index 5553d21..4afcc37 100644
> > --- a/include/sbi/sbi_domain.h
> > +++ b/include/sbi/sbi_domain.h
> > @@ -154,6 +154,21 @@ bool sbi_domain_check_addr(const struct sbi_domain *dom,
> >                            unsigned long addr, unsigned long mode,
> >                            unsigned long access_flags);
> >
> > +/**
> > + * Check whether we can access specified address range for given mode and
> > + * memory region flags under a domain
> > + * @param dom pointer to domain
> > + * @param addr the start of the address range to be checked
> > + * @param size the size of the address range to be checked
> > + * @param mode the privilege mode of access
> > + * @param access_flags bitmask of domain access types (enum sbi_domain_access)
> > + * @return TRUE if access allowed otherwise FALSE
> > + */
> > +bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
> > +                                unsigned long addr, unsigned long size,
> > +                                unsigned long mode,
> > +                                unsigned long access_flags);
> > +
> >  /** Dump domain details on the console */
> >  void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix);
> >
> > diff --git a/lib/sbi/sbi_domain.c b/lib/sbi/sbi_domain.c
> > index f24a8e5..11a547c 100644
> > --- a/lib/sbi/sbi_domain.c
> > +++ b/lib/sbi/sbi_domain.c
> > @@ -195,6 +195,44 @@ static bool is_region_before(const struct sbi_domain_memregion *regA,
> >         return FALSE;
> >  }
> >
> > +static const struct sbi_domain_memregion *find_region(
> > +                                               const struct sbi_domain *dom,
> > +                                               unsigned long addr)
> > +{
> > +       unsigned long rstart, rend;
> > +       struct sbi_domain_memregion *reg;
> > +
> > +       sbi_domain_for_each_memregion(dom, reg) {
> > +               rstart = reg->base;
> > +               rend = (reg->order < __riscv_xlen) ?
> > +                       rstart + ((1UL << reg->order) - 1) : -1UL;
> > +               if (rstart <= addr && addr <= rend)
>
> addr < rend?

Never mind. Looks good.

>
> > +                       return reg;
> > +       }
> > +
> > +       return NULL;
> > +}
> > +
> > +static const struct sbi_domain_memregion *find_next_subset_region(
> > +                               const struct sbi_domain *dom,
> > +                               const struct sbi_domain_memregion *reg,
> > +                               unsigned long addr)
> > +{
> > +       struct sbi_domain_memregion *sreg, *ret = NULL;
> > +
> > +       sbi_domain_for_each_memregion(dom, sreg) {
> > +               if (sreg == reg || (sreg->base <= addr) ||
> > +                   !is_region_subset(sreg, reg))
> > +                       continue;
> > +
> > +               if (!ret || (sreg->base < ret->base) ||
> > +                   ((sreg->base == ret->base) && (sreg->order < ret->order)))
> > +                       ret = sreg;
> > +       }
> > +
> > +       return ret;
> > +}
> > +
> >  static int sanitize_domain(const struct sbi_platform *plat,
> >                            struct sbi_domain *dom)
> >  {
> > @@ -303,6 +341,37 @@ static int sanitize_domain(const struct sbi_platform *plat,
> >         return 0;
> >  }
> >
> > +bool sbi_domain_check_addr_range(const struct sbi_domain *dom,
> > +                                unsigned long addr, unsigned long size,
> > +                                unsigned long mode,
> > +                                unsigned long access_flags)
> > +{
> > +       unsigned long max = addr + size;
> > +       const struct sbi_domain_memregion *reg, *sreg;
> > +
> > +       if (!dom)
> > +               return FALSE;
> > +
> > +       while (addr < max) {
> > +               reg = find_region(dom, addr);
> > +               if (!reg)
> > +                       return FALSE;
> > +
> > +               if (!sbi_domain_check_addr(dom, addr, mode, access_flags))
> > +                       return FALSE;
> > +
> > +               sreg = find_next_subset_region(dom, reg, addr);
> > +               if (sreg)
> > +                       addr = sreg->base;
> > +               else if (reg->order < __riscv_xlen)
> > +                       addr = reg->base + (1UL << reg->order);
> > +               else
> > +                       break;
> > +       }
> > +
> > +       return TRUE;
> > +}
> > +
> >  void sbi_domain_dump(const struct sbi_domain *dom, const char *suffix)
> >  {
> >         u32 i, k;
>

Reviewed-by: Bin Meng <bmeng at tinylab.org>