On Fri, 3 Jul 2020 14:30:01 +0200
Andrew Jones <drjones@xxxxxxxxxx> wrote:
[...]
> > -void *alloc_vpages(ulong nr)
> > +/*
> > + * Allocate a certain number of pages from the virtual address
> > space (without
> > + * physical backing).
> > + *
> > + * nr is the number of pages to allocate
> > + * alignment_pages is the alignment of the allocation *in pages*
> > + */
> > +static void *alloc_vpages_intern(ulong nr, unsigned int
> > alignment_pages)
>
> This helper function isn't necessary. Just introduce
> alloc_vpages_aligned() and then call alloc_vpages_aligned(nr, 1) from
> alloc_vpages().
the helper will actually be useful in future patches.
maybe I should have written that in the patch description.
I can respin without helper if you prefer (and introduce it when
needed) or simply update the patch description.
> > {
> > uintptr_t ptr;
> >
> > spin_lock(&lock);
> > ptr = (uintptr_t)vfree_top;
> > ptr -= PAGE_SIZE * nr;
> > + ptr &= GENMASK_ULL(63, PAGE_SHIFT +
> > get_order(alignment_pages)); vfree_top = (void *)ptr;
> > spin_unlock(&lock);
> >
> > @@ -32,6 +41,16 @@ void *alloc_vpages(ulong nr)
> > return (void *)ptr;
> > }
> >
> > +void *alloc_vpages(ulong nr)
> > +{
> > + return alloc_vpages_intern(nr, 1);
> > +}
> > +
> > +void *alloc_vpages_aligned(ulong nr, unsigned int alignment_pages)
> > +{
> > + return alloc_vpages_intern(nr, alignment_pages);
> > +}
> > +
> > void *alloc_vpage(void)
> > {
> > return alloc_vpages(1);
> > @@ -55,17 +74,22 @@ void *vmap(phys_addr_t phys, size_t size)
> > return mem;
> > }
> >
> > +/*
> > + * Allocate virtual memory, with the specified minimum alignment.
> > + */
> > static void *vm_memalign(size_t alignment, size_t size)
> > {
> > + phys_addr_t pa;
> > void *mem, *p;
> > - size_t pages;
> >
> > - assert(alignment <= PAGE_SIZE);
> > - size = PAGE_ALIGN(size);
> > - pages = size / PAGE_SIZE;
> > - mem = p = alloc_vpages(pages);
> > - while (pages--) {
> > - phys_addr_t pa = virt_to_phys(alloc_page());
> > + assert(is_power_of_2(alignment));
> > +
> > + size = PAGE_ALIGN(size) / PAGE_SIZE;
> > + alignment = PAGE_ALIGN(alignment) / PAGE_SIZE;
> > + mem = p = alloc_vpages_intern(size, alignment);
> > + while (size--) {
> > + pa = virt_to_phys(alloc_page());
> > + assert(pa);
> > install_page(page_root, pa, p);
> > p += PAGE_SIZE;
> > }
> > --
> > 2.26.2
> >
>
> Otherwise
>
> Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
>
> Thanks,
> drew
>
