On 14.02.20 23:26, Christian Borntraeger wrote:
> From: Janosch Frank <frankja@xxxxxxxxxxxxx>
>
> This adds two new helper functions for doing UV CALLs.
>
> The first variant handles UV CALLs that might have longer busy
> conditions or just need longer when doing partial completion. We should
> schedule when necessary.
>
> The second variant handles UV CALLs that only need the handle but have
> no payload (e.g. destroying a VM). We can provide a simple wrapper for
> those.
>
> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx>
> Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
> [borntraeger@xxxxxxxxxx: patch merging, splitting, fixing]
> Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
> ---
> arch/s390/include/asm/uv.h | 65 +++++++++++++++++++++++++++++++++++---
> 1 file changed, 60 insertions(+), 5 deletions(-)
>
> diff --git a/arch/s390/include/asm/uv.h b/arch/s390/include/asm/uv.h
> index e45963cc7f40..bc452a15ac3f 100644
> --- a/arch/s390/include/asm/uv.h
> +++ b/arch/s390/include/asm/uv.h
> @@ -14,6 +14,7 @@
> #include <linux/types.h>
> #include <linux/errno.h>
> #include <linux/bug.h>
> +#include <linux/sched.h>
> #include <asm/page.h>
> #include <asm/gmap.h>
>
> @@ -91,6 +92,19 @@ struct uv_cb_cfs {
> u64 paddr;
> } __packed __aligned(8);
>
> +/*
> + * A common UV call struct for calls that take no payload
> + * Examples:
> + * Destroy cpu/config
> + * Verify
> + */
> +struct uv_cb_nodata {
> + struct uv_cb_header header;
> + u64 reserved08[2];
> + u64 handle;
> + u64 reserved20[4];
> +} __packed __aligned(8);
> +
> struct uv_cb_share {
> struct uv_cb_header header;
> u64 reserved08[3];
> @@ -98,21 +112,62 @@ struct uv_cb_share {
> u64 reserved28;
> } __packed __aligned(8);
>
> -static inline int uv_call(unsigned long r1, unsigned long r2)
> +static inline int __uv_call(unsigned long r1, unsigned long r2)
> {
> int cc;
>
> asm volatile(
> - "0: .insn rrf,0xB9A40000,%[r1],%[r2],0,0\n"
> - " brc 3,0b\n"
> - " ipm %[cc]\n"
> - " srl %[cc],28\n"
> + " .insn rrf,0xB9A40000,%[r1],%[r2],0,0\n"
> + " ipm %[cc]\n"
> + " srl %[cc],28\n"
> : [cc] "=d" (cc)
> : [r1] "a" (r1), [r2] "a" (r2)
> : "memory", "cc");
> return cc;
> }
>
> +static inline int uv_call(unsigned long r1, unsigned long r2)
> +{
> + int cc;
> +
> + do {
> + cc = __uv_call(r1, r2);
> + } while (cc > 1);
> + return cc;
> +}
> +
> +/* Low level uv_call that avoids stalls for long running busy conditions */
> +static inline int uv_call_sched(unsigned long r1, unsigned long r2)
> +{
> + int cc;
> +
> + do {
> + cc = __uv_call(r1, r2);
> + cond_resched();
> + } while (cc > 1);
> + return cc;
> +}
> +
> +/*
> + * special variant of uv_call that only transports the cpu or guest
> + * handle and the command, like destroy or verify.
> + */
> +static inline int uv_cmd_nodata(u64 handle, u16 cmd, u16 *rc, u16 *rrc)
> +{
> + struct uv_cb_nodata uvcb = {
> + .header.cmd = cmd,
> + .header.len = sizeof(uvcb),
> + .handle = handle,
> + };
> + int cc;
> +
> + WARN(!handle, "No handle provided to Ultravisor call cmd %x\n", cmd);
> + cc = uv_call_sched(0, (u64)&uvcb);
> + *rc = uvcb.header.rc;
> + *rrc = uvcb.header.rrc;
> + return cc ? -EINVAL : 0;
> +}
> +
> struct uv_info {
> unsigned long inst_calls_list[4];
> unsigned long uv_base_stor_len;
>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
--
Thanks,
David / dhildenb
