[RFC PATCH 13/33] irqchip/gic-v3-its: Generalize device table allocation
Auger Eric
eric.auger at redhat.com
Thu Mar 16 01:57:47 PDT 2017
Hi Marc,
On 17/01/2017 11:20, Marc Zyngier wrote:
> As we want to use 2-level tables for VCPUs, let's hack the device
s/VCPUS/vPE table
> table allocator in order to make it slightly more generic. It
> will get reused in subsequent patches.
>
> Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
> ---
> drivers/irqchip/irq-gic-v3-its.c | 26 ++++++++++++++++----------
> 1 file changed, 16 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
> index 5d96b37..dcd4771 100644
> --- a/drivers/irqchip/irq-gic-v3-its.c
> +++ b/drivers/irqchip/irq-gic-v3-its.c
> @@ -1371,26 +1371,19 @@ static struct its_baser *its_get_baser(struct its_node *its, u32 type)
> return NULL;
> }
>
> -static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
> +static bool its_alloc_table_entry(struct its_baser *baser, u32 id)
> {
> - struct its_baser *baser;
> struct page *page;
> u32 esz, idx;
> __le64 *table;
>
> - baser = its_get_baser(its, GITS_BASER_TYPE_DEVICE);
> -
> - /* Don't allow device id that exceeds ITS hardware limit */
> - if (!baser)
> - return (ilog2(dev_id) < its->device_ids);
> -
> /* Don't allow device id that exceeds single, flat table limit */
> esz = GITS_BASER_ENTRY_SIZE(baser->val);
> if (!(baser->val & GITS_BASER_INDIRECT))
> - return (dev_id < (PAGE_ORDER_TO_SIZE(baser->order) / esz));
> + return (id < (PAGE_ORDER_TO_SIZE(baser->order) / esz));
>
> /* Compute 1st level table index & check if that exceeds table limit */
> - idx = dev_id >> ilog2(baser->psz / esz);
> + idx = id >> ilog2(baser->psz / esz);
> if (idx >= (PAGE_ORDER_TO_SIZE(baser->order) / GITS_LVL1_ENTRY_SIZE))
> return false;
>
> @@ -1419,6 +1412,19 @@ static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
> return true;
> }
>
> +static bool its_alloc_device_table(struct its_node *its, u32 dev_id)
I would rename this into its_alloc_device_table_entry().
> +{
> + struct its_baser *baser;
> +
> + baser = its_get_baser(its, GITS_BASER_TYPE_DEVICE);
> +
> + /* Don't allow device id that exceeds ITS hardware limit */
> + if (!baser)
> + return (ilog2(dev_id) < its->device_ids);
I don't get above check and comment. Shouldn't you first check the baser
is not void and second check the dev_id does not overflow the HW capacity?
Besides
Reviewed-by: Eric Auger <eric.auger at redhat.com>
Eric
> +
> + return its_alloc_table_entry(baser, dev_id);
> +}
> +
> static struct its_device *its_create_device(struct its_node *its, u32 dev_id,
> int nvecs)
> {
>
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