[RFC 5/8] lib: add small API for handling register snapshots

[Dmitry Baryshkov]

On Thu, 3 Jun 2021 at 17:41, Rob Clark <robdclark at gmail.com> wrote:
>
> On Fri, May 28, 2021 at 5:25 PM Dmitry Baryshkov
> <dmitry.baryshkov at linaro.org> wrote:
> >
> > Add small API covering lists of register dumps. Currently this is a part
> > of MSM DRM driver, but is extracted as it might be usefull to other
> > drivers too.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> > ---
> >  include/linux/dump_state.h | 78 ++++++++++++++++++++++++++++++++++++++
> >  lib/Kconfig                |  3 ++
> >  lib/Makefile               |  1 +
> >  lib/dump_state.c           | 51 +++++++++++++++++++++++++
> >  4 files changed, 133 insertions(+)
> >  create mode 100644 include/linux/dump_state.h
> >  create mode 100644 lib/dump_state.c
> >
> [snip]
> > diff --git a/lib/dump_state.c b/lib/dump_state.c
> > new file mode 100644
> > index 000000000000..58d88be65c0a
> > --- /dev/null
> > +++ b/lib/dump_state.c
> > @@ -0,0 +1,51 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
> > + * Copyright (c) 2021, Linaro Ltd
> > + */
> > +
> > +#include <linux/dump_state.h>
> > +#include <linux/slab.h>
> > +
> > +void dump_state_free_blocks(struct dump_state *state)
> > +{
> > +       struct dump_state_block *block, *tmp;
> > +
> > +       list_for_each_entry_safe(block, tmp, &state->blocks, node) {
> > +               list_del(&block->node);
> > +               kfree(block);
> > +       }
> > +}
> > +EXPORT_SYMBOL(dump_state_free_blocks);
>
> nit, perhaps EXPORT_SYMBOL_GPL()?

I don't really care. What is the current recommendation?

>
> BR,
> -R
>
> > +
> > +struct dump_state_block *dump_state_allocate_block_va(void __iomem *base_addr, size_t len, gfp_t gfp, const char *fmt, va_list args)
> > +{
> > +       struct dump_state_block *block = kzalloc(sizeof(*block) + len, gfp);
> > +
> > +       if (!block)
> > +               return ERR_PTR(-ENOMEM);
> > +
> > +       vsnprintf(block->name, sizeof(block->name), fmt, args);
> > +
> > +       INIT_LIST_HEAD(&block->node);
> > +       block->size = len;
> > +       block->base_addr = base_addr;
> > +
> > +       return block;
> > +}
> > +EXPORT_SYMBOL(dump_state_allocate_block);
> > +
> > +struct dump_state_block *dump_state_allocate_block(void __iomem *base_addr, size_t len, gfp_t gfp, const char *fmt, ...)
> > +{
> > +       struct dump_state_block *block;
> > +       va_list va;
> > +
> > +       va_start(va, fmt);
> > +
> > +       block = dump_state_allocate_block_va(base_addr, len, gfp, fmt, va);
> > +
> > +       va_end(va);
> > +
> > +       return block;
> > +}
> > +EXPORT_SYMBOL(dump_state_allocate_block_va);
> > --
> > 2.30.2
> >



-- 
With best wishes
Dmitry