[PATCH RFC 36/39] drivers/xen: xen_shim_domain() support

From: Joao Martins <joao.m.martins@oracle.com>
To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	xen-devel@lists.xenproject.org
Cc: "Ankur Arora" <ankur.a.arora@oracle.com>,
	"Boris Ostrovsky" <boris.ostrovsky@oracle.com>,
	"Joao Martins" <joao.m.martins@oracle.com>,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>,
	"Juergen Gross" <jgross@suse.com>,
	"Stefano Stabellini" <sstabellini@kernel.org>
Subject: [PATCH RFC 36/39] drivers/xen: xen_shim_domain() support
Date: Wed, 20 Feb 2019 20:16:06 +0000	[thread overview]
Message-ID: <20190220201609.28290-37-joao.m.martins@oracle.com> (raw)
In-Reply-To: <20190220201609.28290-1-joao.m.martins@oracle.com>

Enable /dev/xen/{gntdev,evtchn} and /proc/xen/ for xen_shim_domain().

These interfaces will be used by xenstored to initialize its
event channel port and the kva used to communicate with the
xenbus driver.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
 drivers/xen/evtchn.c           | 4 +++-
 drivers/xen/privcmd.c          | 5 ++++-
 drivers/xen/xenbus/xenbus_xs.c | 2 +-
 drivers/xen/xenfs/super.c      | 7 ++++---
 drivers/xen/xenfs/xensyms.c    | 4 ++++
 5 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c
index 6d1a5e58968f..367390eb5883 100644
--- a/drivers/xen/evtchn.c
+++ b/drivers/xen/evtchn.c
@@ -708,13 +708,14 @@ static int __init evtchn_init(void)
 {
 	int err;
 
-	if (!xen_domain())
+	if (!xen_domain() && !xen_shim_domain_get())
 		return -ENODEV;
 
 	/* Create '/dev/xen/evtchn'. */
 	err = misc_register(&evtchn_miscdev);
 	if (err != 0) {
 		pr_err("Could not register /dev/xen/evtchn\n");
+		xen_shim_domain_put();
 		return err;
 	}
 
@@ -726,6 +727,7 @@ static int __init evtchn_init(void)
 static void __exit evtchn_cleanup(void)
 {
 	misc_deregister(&evtchn_miscdev);
+	xen_shim_domain_put();
 }
 
 module_init(evtchn_init);
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index b24ddac1604b..a063ad5c8260 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -999,12 +999,13 @@ static int __init privcmd_init(void)
 {
 	int err;
 
-	if (!xen_domain())
+	if (!xen_domain() && !xen_shim_domain_get())
 		return -ENODEV;
 
 	err = misc_register(&privcmd_dev);
 	if (err != 0) {
 		pr_err("Could not register Xen privcmd device\n");
+		xen_shim_domain_put();
 		return err;
 	}
 
@@ -1012,6 +1013,7 @@ static int __init privcmd_init(void)
 	if (err != 0) {
 		pr_err("Could not register Xen hypercall-buf device\n");
 		misc_deregister(&privcmd_dev);
+		xen_shim_domain_put();
 		return err;
 	}
 
@@ -1022,6 +1024,7 @@ static void __exit privcmd_exit(void)
 {
 	misc_deregister(&privcmd_dev);
 	misc_deregister(&xen_privcmdbuf_dev);
+	xen_shim_domain_put();
 }
 
 module_init(privcmd_init);
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index bd6db3703972..062c0a5fa415 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -735,7 +735,7 @@ static void xs_reset_watches(void)
 {
 	int err;
 
-	if (!xen_hvm_domain() || xen_initial_domain())
+	if (!xen_hvm_domain() || xen_initial_domain() || xen_shim_domain())
 		return;
 
 	if (xen_strict_xenbus_quirk())
diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
index 71ddfb4cf61c..2ef326645880 100644
--- a/drivers/xen/xenfs/super.c
+++ b/drivers/xen/xenfs/super.c
@@ -64,7 +64,8 @@ static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
 	};
 
 	return simple_fill_super(sb, XENFS_SUPER_MAGIC,
-			xen_initial_domain() ? xenfs_init_files : xenfs_files);
+			xen_initial_domain() || xen_shim_domain() ?
+				xenfs_init_files : xenfs_files);
 }
 
 static struct dentry *xenfs_mount(struct file_system_type *fs_type,
@@ -84,7 +85,7 @@ MODULE_ALIAS_FS("xenfs");
 
 static int __init xenfs_init(void)
 {
-	if (xen_domain())
+	if (xen_domain() || xen_shim_domain())
 		return register_filesystem(&xenfs_type);
 
 	return 0;
@@ -92,7 +93,7 @@ static int __init xenfs_init(void)
 
 static void __exit xenfs_exit(void)
 {
-	if (xen_domain())
+	if (xen_domain() || xen_shim_domain())
 		unregister_filesystem(&xenfs_type);
 }
 
diff --git a/drivers/xen/xenfs/xensyms.c b/drivers/xen/xenfs/xensyms.c
index c6c73a33c44d..79bccb53d344 100644
--- a/drivers/xen/xenfs/xensyms.c
+++ b/drivers/xen/xenfs/xensyms.c
@@ -8,6 +8,7 @@
 #include <xen/interface/platform.h>
 #include <asm/xen/hypercall.h>
 #include <xen/xen-ops.h>
+#include <xen/xen.h>
 #include "xenfs.h"
 
 
@@ -114,6 +115,9 @@ static int xensyms_open(struct inode *inode, struct file *file)
 	struct xensyms *xs;
 	int ret;
 
+	if (xen_shim_domain())
+		return -EINVAL;
+
 	ret = seq_open_private(file, &xensyms_seq_ops,
 			       sizeof(struct xensyms));
 	if (ret)
-- 
2.11.0

