On 19/06/2020 15:06, Leonardo Bras wrote:
> Move the window-removing part of remove_ddw into a new function
> (remove_dma_window), so it can be used to remove other DMA windows.
>
> It's useful for removing DMA windows that don't create DIRECT64_PROPNAME
> property, like the default DMA window from the device, which uses
> "ibm,dma-window".
>
> Signed-off-by: Leonardo Bras <leobra...@gmail.com>
> ---
> arch/powerpc/platforms/pseries/iommu.c | 53 +++++++++++++++-----------
> 1 file changed, 31 insertions(+), 22 deletions(-)
>
> diff --git a/arch/powerpc/platforms/pseries/iommu.c
> b/arch/powerpc/platforms/pseries/iommu.c
> index 5e1fbc176a37..de633f6ae093 100644
> --- a/arch/powerpc/platforms/pseries/iommu.c
> +++ b/arch/powerpc/platforms/pseries/iommu.c
> @@ -767,25 +767,14 @@ static int __init disable_ddw_setup(char *str)
>
> early_param("disable_ddw", disable_ddw_setup);
>
> -static void remove_ddw(struct device_node *np, bool remove_prop)
> +static void remove_dma_window(struct device_node *pdn, u32 *ddw_avail,
You do not need the entire ddw_avail here, pass just the token you need.
Also, despite this particular file, the "pdn" name is usually used for
struct pci_dn (not device_node), let's keep it that way.
> + struct property *win)
> {
> struct dynamic_dma_window_prop *dwp;
> - struct property *win64;
> - u32 ddw_avail[3];
> u64 liobn;
> - int ret = 0;
> -
> - ret = of_property_read_u32_array(np, "ibm,ddw-applicable",
> - &ddw_avail[0], 3);
> -
> - win64 = of_find_property(np, DIRECT64_PROPNAME, NULL);
> - if (!win64)
> - return;
> -
> - if (ret || win64->length < sizeof(*dwp))
> - goto delprop;
> + int ret;
>
> - dwp = win64->value;
> + dwp = win->value;
> liobn = (u64)be32_to_cpu(dwp->liobn);
>
> /* clear the whole window, note the arg is in kernel pages */
> @@ -793,24 +782,44 @@ static void remove_ddw(struct device_node *np, bool
> remove_prop)
> 1ULL << (be32_to_cpu(dwp->window_shift) - PAGE_SHIFT), dwp);
> if (ret)
> pr_warn("%pOF failed to clear tces in window.\n",
> - np);
> + pdn);
> else
> pr_debug("%pOF successfully cleared tces in window.\n",
> - np);
> + pdn);
>
> ret = rtas_call(ddw_avail[2], 1, 1, NULL, liobn);
> if (ret)
> pr_warn("%pOF: failed to remove direct window: rtas returned "
> "%d to ibm,remove-pe-dma-window(%x) %llx\n",
> - np, ret, ddw_avail[2], liobn);
> + pdn, ret, ddw_avail[2], liobn);
> else
> pr_debug("%pOF: successfully removed direct window: rtas
> returned "
> "%d to ibm,remove-pe-dma-window(%x) %llx\n",
> - np, ret, ddw_avail[2], liobn);
> + pdn, ret, ddw_avail[2], liobn);
> +}
> +
> +static void remove_ddw(struct device_node *np, bool remove_prop)
> +{
> + struct property *win;
> + u32 ddw_avail[3];
> + int ret = 0;
> +
> + ret = of_property_read_u32_array(np, "ibm,ddw-applicable",
> + &ddw_avail[0], 3);
> + if (ret)
> + return;
> +
> + win = of_find_property(np, DIRECT64_PROPNAME, NULL);
> + if (!win)
> + return;
> +
> + if (win->length >= sizeof(struct dynamic_dma_window_prop))
Any good reason not to make it "=="? Is there something optional or we
expect extension (which may not grow from the end but may add cells in
between). Thanks,
> + remove_dma_window(np, ddw_avail, win);
> +
> + if (!remove_prop)
> + return;
>
> -delprop:
> - if (remove_prop)
> - ret = of_remove_property(np, win64);
> + ret = of_remove_property(np, win);
> if (ret)
> pr_warn("%pOF: failed to remove direct window property: %d\n",
> np, ret);
>
--
Alexey
