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authorAlastair D'Silva <alastair@d-silva.org>2018-05-11 08:13:02 +0200
committerMichael Ellerman <mpe@ellerman.id.au>2018-06-03 12:40:32 +0200
commit02a8e5bc1c06045f36423bd9632ad9f40da18d3f (patch)
treee6c82dfe03d4c5639253ed3b058ee67c20a38811
parentocxl: Expose the thread_id needed for wait on POWER9 (diff)
downloadlinux-02a8e5bc1c06045f36423bd9632ad9f40da18d3f.tar.xz
linux-02a8e5bc1c06045f36423bd9632ad9f40da18d3f.zip
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>
-rw-r--r--drivers/misc/ocxl/file.c25
-rw-r--r--include/uapi/misc/ocxl.h6
2 files changed, 31 insertions, 0 deletions
diff --git a/drivers/misc/ocxl/file.c b/drivers/misc/ocxl/file.c
index eb409a469f21..33ae46ce0a8a 100644
--- a/drivers/misc/ocxl/file.c
+++ b/drivers/misc/ocxl/file.c
@@ -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;
}
diff --git a/include/uapi/misc/ocxl.h b/include/uapi/misc/ocxl.h
index 561e6f0dfcb7..97937cfa3baa 100644
--- a/include/uapi/misc/ocxl.h
+++ b/include/uapi/misc/ocxl.h
@@ -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 */