On Mon, Sep 18, 2023 at 06:27:28PM +0530, Anup Patel wrote:
> To use irqfd with in-kernel AIA irqchip, we add custom
> irq__add_irqfd and irq__del_irqfd functions. This allows
> us to defer actual KVM_IRQFD ioctl() until AIA irqchip
> is initialized by KVMTOOL.
>
> Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
> ---
> riscv/include/kvm/kvm-arch.h | 11 ++++++
> riscv/irq.c | 73 ++++++++++++++++++++++++++++++++++++
> 2 files changed, 84 insertions(+)
>
> diff --git a/riscv/include/kvm/kvm-arch.h b/riscv/include/kvm/kvm-arch.h
> index cd37fc6..1a8af6a 100644
> --- a/riscv/include/kvm/kvm-arch.h
> +++ b/riscv/include/kvm/kvm-arch.h
> @@ -98,11 +98,22 @@ extern void (*riscv_irqchip_generate_fdt_node)(void *fdt, struct kvm *kvm);
> extern u32 riscv_irqchip_phandle;
> extern u32 riscv_irqchip_msi_phandle;
> extern bool riscv_irqchip_line_sensing;
> +extern bool riscv_irqchip_irqfd_ready;
>
> void plic__create(struct kvm *kvm);
>
> void pci__generate_fdt_nodes(void *fdt);
>
> +int riscv__add_irqfd(struct kvm *kvm, unsigned int gsi, int trigger_fd,
> + int resample_fd);
> +
> +void riscv__del_irqfd(struct kvm *kvm, unsigned int gsi, int trigger_fd);
> +
> +#define irq__add_irqfd riscv__add_irqfd
> +#define irq__del_irqfd riscv__del_irqfd
> +
> +int riscv__setup_irqfd_lines(struct kvm *kvm);
> +
> void riscv__generate_irq_prop(void *fdt, u8 irq, enum irq_type irq_type);
>
> void riscv__irqchip_create(struct kvm *kvm);
> diff --git a/riscv/irq.c b/riscv/irq.c
> index b608a2f..e6c0939 100644
> --- a/riscv/irq.c
> +++ b/riscv/irq.c
> @@ -12,6 +12,7 @@ void (*riscv_irqchip_generate_fdt_node)(void *fdt, struct kvm *kvm) = NULL;
> u32 riscv_irqchip_phandle = PHANDLE_RESERVED;
> u32 riscv_irqchip_msi_phandle = PHANDLE_RESERVED;
> bool riscv_irqchip_line_sensing = false;
> +bool riscv_irqchip_irqfd_ready = false;
>
> void kvm__irq_line(struct kvm *kvm, int irq, int level)
> {
> @@ -46,6 +47,78 @@ void kvm__irq_trigger(struct kvm *kvm, int irq)
> }
> }
>
> +struct riscv_irqfd_line {
> + unsigned int gsi;
> + int trigger_fd;
> + int resample_fd;
> + struct list_head list;
> +};
> +
> +static LIST_HEAD(irqfd_lines);
> +
> +int riscv__add_irqfd(struct kvm *kvm, unsigned int gsi, int trigger_fd,
> + int resample_fd)
> +{
> + struct riscv_irqfd_line *line;
> +
> + if (riscv_irqchip_irqfd_ready)
> + return irq__common_add_irqfd(kvm, gsi, trigger_fd,
> + resample_fd);
> +
> + /* Postpone the routing setup until we have a distributor */
This comment comes from the Arm code. We probably want to replace
distributor with "until the AIA is initialized" or something.
> + line = malloc(sizeof(*line));
> + if (!line)
> + return -ENOMEM;
> +
> + *line = (struct riscv_irqfd_line) {
> + .gsi = gsi,
> + .trigger_fd = trigger_fd,
> + .resample_fd = resample_fd,
> + };
> + list_add(&line->list, &irqfd_lines);
> +
> + return 0;
> +}
> +
> +void riscv__del_irqfd(struct kvm *kvm, unsigned int gsi, int trigger_fd)
> +{
> + struct riscv_irqfd_line *line;
> +
> + if (riscv_irqchip_irqfd_ready) {
> + irq__common_del_irqfd(kvm, gsi, trigger_fd);
> + return;
> + }
> +
> + list_for_each_entry(line, &irqfd_lines, list) {
> + if (line->gsi != gsi)
> + continue;
> +
> + list_del(&line->list);
> + free(line);
> + break;
> + }
> +}
> +
> +int riscv__setup_irqfd_lines(struct kvm *kvm)
> +{
> + int ret;
> + struct riscv_irqfd_line *line, *tmp;
> +
> + list_for_each_entry_safe(line, tmp, &irqfd_lines, list) {
> + ret = irq__common_add_irqfd(kvm, line->gsi, line->trigger_fd,
> + line->resample_fd);
> + if (ret < 0) {
> + pr_err("Failed to register IRQFD");
> + return ret;
> + }
> +
> + list_del(&line->list);
> + free(line);
> + }
> +
> + return 0;
> +}
> +
> void riscv__generate_irq_prop(void *fdt, u8 irq, enum irq_type irq_type)
> {
> u32 prop[2], size;
> --
> 2.34.1
>
Other than the comment,
Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
