Re: [PATCH v15 04/16] powerpc, kexec_file: factor out memblock-based arch_kexec_walk_mem()

From: AKASHI Takahiro
Date: Tue Oct 02 2018 - 02:19:02 EST


On Sun, Sep 30, 2018 at 06:08:34PM +0800, Dave Young wrote:
> Hi AKASHI,
>
> On 09/28/18 at 03:48pm, AKASHI Takahiro wrote:
> > Memblock list is another source for usable system memory layout.
> > So move powerpc's arch_kexec_walk_mem() to common code so that other
> > memblock-based architectures, particularly arm64, can also utilise it.
> > A moved function is now renamed to kexec_walk_memblock() and integrated
> > into kexec_locate_mem_hole(), which will now be usable for all
> > architectures with no need for overriding arch_kexec_walk_mem().
> >
> > With this change, arch_kexec_walk_mem() need no longer be a weak function,
> > and was now renamed to kexec_walk_resources().
> >
> > Since powerpc doesn't support kdump in its kexec_file_load(), the current
> > kexec_walk_memblock() won't work for kdump either in this form, this will
> > be fixed in the next patch.
> >
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
> > Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> > Acked-by: Dave Young <dyoung@xxxxxxxxxx>
> > Cc: Vivek Goyal <vgoyal@xxxxxxxxxx>
> > Cc: Baoquan He <bhe@xxxxxxxxxx>
> > Acked-by: James Morse <james.morse@xxxxxxx>
>
> [snip]
>
> > +
> > /**
> > * arch_kexec_walk_mem - call func(data) on free memory regions
>
> The function name should be updated as well.

Ah, thank you.
-Takahiro Akashi

> > * @kbuf: Context info for the search. Also passed to @func.
> > @@ -510,8 +560,8 @@ static int locate_mem_hole_callback(struct resource *res, void *arg)
> > * and that value will be returned. If all free regions are visited without
> > * func returning non-zero, then zero will be returned.
> > */
> > -int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
> > - int (*func)(struct resource *, void *))
> > +static int kexec_walk_resources(struct kexec_buf *kbuf,
> > + int (*func)(struct resource *, void *))
> > {
> > if (kbuf->image->type == KEXEC_TYPE_CRASH)
> > return walk_iomem_res_desc(crashk_res.desc,
> > @@ -538,7 +588,11 @@ int kexec_locate_mem_hole(struct kexec_buf *kbuf)
> > if (kbuf->mem != KEXEC_BUF_MEM_UNKNOWN)
> > return 0;
> >
> > - ret = arch_kexec_walk_mem(kbuf, locate_mem_hole_callback);
> > + if (IS_ENABLED(CONFIG_HAVE_MEMBLOCK) &&
> > + !IS_ENABLED(CONFIG_ARCH_DISCARD_MEMBLOCK))
> > + ret = kexec_walk_memblock(kbuf, locate_mem_hole_callback);
> > + else
> > + ret = kexec_walk_resources(kbuf, locate_mem_hole_callback);
> >
> > return ret == 1 ? 0 : -EADDRNOTAVAIL;
> > }
> > --
> > 2.19.0
> >
>
> Thanks
> Dave