> Date: Sat, 5 Feb 2022 22:34:10 +1100
> From: Jonathan Gray <[email protected]>
>
> On Sat, Feb 05, 2022 at 11:44:03AM +0100, Mark Kettenis wrote:
> > We want to get rid of the uvm_km_valloc() interfaces in favour of
> > km_alloc(). This changes the calls in drm(4) over. The kv_physwait
> > struct is made static to prevent collission with a symbol in
> > vm_machdep.c on some architectures. The goal is to move this into
> > uvm/uvm_km.c eventually.
> >
> > Just to make sure I didn't screw the conversion up somehow a few tests
> > on a mix of inteldrm(4) and amdgpu(4) systems would be good.
> >
> > ok?
> >
> >
> > Index: dev/pci/drm/drm_linux.c
> > ===================================================================
> > RCS file: /cvs/src/sys/dev/pci/drm/drm_linux.c,v
> > retrieving revision 1.89
> > diff -u -p -r1.89 drm_linux.c
> > --- dev/pci/drm/drm_linux.c 21 Jan 2022 23:49:36 -0000 1.89
> > +++ dev/pci/drm/drm_linux.c 5 Feb 2022 10:40:22 -0000
> > @@ -564,6 +564,11 @@ __pagevec_release(struct pagevec *pvec)
> > pagevec_reinit(pvec);
> > }
> >
> > +static struct kmem_va_mode kv_physwait = {
> > + .kv_map = &phys_map,
> > + .kv_wait = 1,
> > +};
> > +
> > void *
> > kmap(struct vm_page *pg)
> > {
> > @@ -572,7 +577,7 @@ kmap(struct vm_page *pg)
> > #if defined (__HAVE_PMAP_DIRECT)
> > va = pmap_map_direct(pg);
> > #else
> > - va = uvm_km_valloc_wait(phys_map, PAGE_SIZE);
> > + va = (vaddr_t)km_alloc(PAGE_SIZE, &kv_physwait, &kp_none, &kd_waitok);
> > pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), PROT_READ | PROT_WRITE);
> > pmap_update(pmap_kernel());
> > #endif
> > @@ -589,7 +594,7 @@ kunmap_va(void *addr)
> > #else
> > pmap_kremove(va, PAGE_SIZE);
> > pmap_update(pmap_kernel());
> > - uvm_km_free_wakeup(phys_map, va, PAGE_SIZE);
> > + km_free((void *)va, PAGE_SIZE, &kv_physwait, &kp_none);
> > #endif
> > }
> >
> > @@ -624,7 +629,8 @@ vmap(struct vm_page **pages, unsigned in
> > paddr_t pa;
> > int i;
> >
> > - va = uvm_km_valloc(kernel_map, PAGE_SIZE * npages);
> > + va = (vaddr_t)km_alloc(PAGE_SIZE * npages, &kv_any, &kp_none,
> > + &kd_nowait);
>
> this could be kd_waitok as the linux vmap() uses might_sleep()
> but I suppose that would be a change in behaviour/different diff
Actually that doesn't make a difference. Specifying kd_waitok will
only make it wait for physical pages. But we're passing kp_none so no
physical pages are allocated.
Yes, this is confusing and continues to trip people up.
>
> > if (va == 0)
> > return NULL;
> > for (i = 0; i < npages; i++) {
> > @@ -645,7 +651,7 @@ vunmap(void *addr, size_t size)
> >
> > pmap_remove(pmap_kernel(), va, va + size);
> > pmap_update(pmap_kernel());
> > - uvm_km_free(kernel_map, va, size);
> > + km_free((void *)va, size, &kv_any, &kp_none);
> > }
> >
> > bool
> >
> >
>
