ocxl: Add an IOCTL so userspace knows what OCXL features are available

In order for a userspace AFU driver to call the POWER9 specific
OCXL_IOCTL_ENABLE_P9_WAIT, it needs to verify that it can actually
make that call.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Alastair D'Silva 2018-05-11 16:13:02 +10:00 committed by Michael Ellerman
parent e948e06fc6
commit 02a8e5bc1c
2 changed files with 31 additions and 0 deletions

View File

@ -168,12 +168,32 @@ static long afu_ioctl_enable_p9_wait(struct ocxl_context *ctx,
}
#endif
static long afu_ioctl_get_features(struct ocxl_context *ctx,
struct ocxl_ioctl_features __user *uarg)
{
struct ocxl_ioctl_features arg;
memset(&arg, 0, sizeof(arg));
#ifdef CONFIG_PPC64
if (cpu_has_feature(CPU_FTR_P9_TIDR))
arg.flags[0] |= OCXL_IOCTL_FEATURES_FLAGS0_P9_WAIT;
#endif
if (copy_to_user(uarg, &arg, sizeof(arg)))
return -EFAULT;
return 0;
}
#define CMD_STR(x) (x == OCXL_IOCTL_ATTACH ? "ATTACH" : \
x == OCXL_IOCTL_IRQ_ALLOC ? "IRQ_ALLOC" : \
x == OCXL_IOCTL_IRQ_FREE ? "IRQ_FREE" : \
x == OCXL_IOCTL_IRQ_SET_FD ? "IRQ_SET_FD" : \
x == OCXL_IOCTL_GET_METADATA ? "GET_METADATA" : \
x == OCXL_IOCTL_ENABLE_P9_WAIT ? "ENABLE_P9_WAIT" : \
x == OCXL_IOCTL_GET_FEATURES ? "GET_FEATURES" : \
"UNKNOWN")
static long afu_ioctl(struct file *file, unsigned int cmd,
@ -239,6 +259,11 @@ static long afu_ioctl(struct file *file, unsigned int cmd,
break;
#endif
case OCXL_IOCTL_GET_FEATURES:
rc = afu_ioctl_get_features(ctx,
(struct ocxl_ioctl_features __user *) args);
break;
default:
rc = -EINVAL;
}

View File

@ -55,6 +55,11 @@ struct ocxl_ioctl_p9_wait {
__u64 reserved3[3];
};
#define OCXL_IOCTL_FEATURES_FLAGS0_P9_WAIT 0x01
struct ocxl_ioctl_features {
__u64 flags[4];
};
struct ocxl_ioctl_irq_fd {
__u64 irq_offset;
__s32 eventfd;
@ -70,5 +75,6 @@ struct ocxl_ioctl_irq_fd {
#define OCXL_IOCTL_IRQ_SET_FD _IOW(OCXL_MAGIC, 0x13, struct ocxl_ioctl_irq_fd)
#define OCXL_IOCTL_GET_METADATA _IOR(OCXL_MAGIC, 0x14, struct ocxl_ioctl_metadata)
#define OCXL_IOCTL_ENABLE_P9_WAIT _IOR(OCXL_MAGIC, 0x15, struct ocxl_ioctl_p9_wait)
#define OCXL_IOCTL_GET_FEATURES _IOR(OCXL_MAGIC, 0x16, struct ocxl_ioctl_features)
#endif /* _UAPI_MISC_OCXL_H */