Re: [PATCH v9 11/27] gunyah: vm_mgr: Introduce basic VM Manager
From: Elliot Berman
Date: Mon Feb 06 2023 - 19:37:20 EST
On 2/2/2023 4:54 AM, Srinivas Kandagatla wrote:
On 20/01/2023 22:46, Elliot Berman wrote:
Gunyah VM manager is a kernel moduel which exposes an interface to
Gunyah userspace to load, run, and interact with other Gunyah virtual
machines. The interface is a character device at /dev/gunyah.
Add a basic VM manager driver. Upcoming patches will add more ioctls
into this driver.
Co-developed-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
Signed-off-by: Prakruthi Deepak Heragu <quic_pheragu@xxxxxxxxxxx>
Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx>
---
.../userspace-api/ioctl/ioctl-number.rst | 1 +
drivers/virt/gunyah/Makefile | 2 +-
drivers/virt/gunyah/rsc_mgr.c | 51 +++++++-
drivers/virt/gunyah/vm_mgr.c | 117 ++++++++++++++++++
drivers/virt/gunyah/vm_mgr.h | 20 +++
include/linux/gunyah_rsc_mgr.h | 3 +
include/uapi/linux/gunyah.h | 23 ++++
7 files changed, 215 insertions(+), 2 deletions(-)
create mode 100644 drivers/virt/gunyah/vm_mgr.c
create mode 100644 drivers/virt/gunyah/vm_mgr.h
create mode 100644 include/uapi/linux/gunyah.h
diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst
b/Documentation/userspace-api/ioctl/ioctl-number.rst
index eb045fc495a4..8696dc3cdd83 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -137,6 +137,7 @@ Code Seq# Include
File Comments
'F' DD video/sstfb.h
conflict!
'G' 00-3F drivers/misc/sgi-gru/grulib.h
conflict!
'G' 00-0F xen/gntalloc.h, xen/gntdev.h
conflict!
+'G' 00-0f linux/gunyah.h
conflict!
'H' 00-7F linux/hiddev.h
conflict!
'H' 00-0F linux/hidraw.h
conflict!
'H' 01 linux/mei.h
conflict!
diff --git a/drivers/virt/gunyah/Makefile b/drivers/virt/gunyah/Makefile
index de29769f2f3f..03951cf82023 100644
--- a/drivers/virt/gunyah/Makefile
+++ b/drivers/virt/gunyah/Makefile
@@ -2,5 +2,5 @@
obj-$(CONFIG_GUNYAH) += gunyah.o
-gunyah_rsc_mgr-y += rsc_mgr.o rsc_mgr_rpc.o
+gunyah_rsc_mgr-y += rsc_mgr.o rsc_mgr_rpc.o vm_mgr.o
obj-$(CONFIG_GUNYAH) += gunyah_rsc_mgr.o
diff --git a/drivers/virt/gunyah/rsc_mgr.c
b/drivers/virt/gunyah/rsc_mgr.c
index 382f9943fd31..95f4aa928aaf 100644
--- a/drivers/virt/gunyah/rsc_mgr.c
+++ b/drivers/virt/gunyah/rsc_mgr.c
@@ -16,8 +16,10 @@
#include <linux/completion.h>
#include <linux/gunyah_rsc_mgr.h>
#include <linux/platform_device.h>
+#include <linux/miscdevice.h>
#include "rsc_mgr.h"
+#include "vm_mgr.h"
#define RM_RPC_API_VERSION_MASK GENMASK(3, 0)
#define RM_RPC_HEADER_WORDS_MASK GENMASK(7, 4)
@@ -105,6 +107,7 @@ struct gh_rm {
struct kmem_cache *cache;
struct mutex send_lock;
+ struct miscdevice miscdev;
struct work_struct recv_work;
};
@@ -526,6 +529,33 @@ int gh_rm_call(struct gh_rm *rm, u32 message_id,
void *req_buff, size_t req_buff
return ret;
}
+void get_gh_rm(struct gh_rm *rm)
+{
+ get_device(rm->dev);
+}
+EXPORT_SYMBOL_GPL(get_gh_rm);
We have 4/5 different vairants of exported symbols now.
EXPORT_SYMBOL_GPL(gunyah_vm_function_unregister);
EXPORT_SYMBOL_GPL(ghvm_add_resource_ticket);
EXPORT_SYMBOL_GPL(gh_vm_mgr_mmio_write);
EXPORT_SYMBOL_GPL(put_gh_rm);
EXPORT_SYMBOL_GPL(get_gunyah_vm);
I think this needs to be cleaned up for consistency reasons.
Cleaned up in the v10. "gh_vm_" will be the prefix.
+
+void put_gh_rm(struct gh_rm *rm)
+{
+ put_device(rm->dev);
+}
+EXPORT_SYMBOL_GPL(put_gh_rm);
+
+static long gh_dev_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
+{
+ struct miscdevice *miscdev = filp->private_data;
+ struct gh_rm *rm = container_of(miscdev, struct gh_rm, miscdev);
+
+ return gh_dev_vm_mgr_ioctl(rm, cmd, arg);
+}
+
+static const struct file_operations gh_dev_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = gh_dev_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
+ .llseek = noop_llseek,
+};
+
static int gh_msgq_platform_probe_direction(struct platform_device
*pdev,
bool tx, int idx, struct gunyah_resource *ghrsc)
{
@@ -582,13 +612,32 @@ static int gh_rm_drv_probe(struct
platform_device *pdev)
rm->msgq_client.rx_callback = gh_rm_msgq_rx_data;
rm->msgq_client.tx_done = gh_rm_msgq_tx_done;
- return gh_msgq_init(&pdev->dev, &rm->msgq, &rm->msgq_client,
&rm->tx_ghrsc, &rm->rx_ghrsc);
+ ret = gh_msgq_init(&pdev->dev, &rm->msgq, &rm->msgq_client,
&rm->tx_ghrsc, &rm->rx_ghrsc);
+ if (ret)
+ goto err_cache;
+
+ rm->miscdev.name = "gunyah";
+ rm->miscdev.minor = MISC_DYNAMIC_MINOR;
+ rm->miscdev.fops = &gh_dev_fops;
+
+ ret = misc_register(&rm->miscdev);
+ if (ret)
+ goto err_msgq;
+
+ return 0;
+err_msgq:
+ mbox_free_channel(gh_msgq_chan(&rm->msgq));
+ gh_msgq_remove(&rm->msgq);
+err_cache:
+ kmem_cache_destroy(rm->cache);
+ return ret;
}
static int gh_rm_drv_remove(struct platform_device *pdev)
{
struct gh_rm *rm = platform_get_drvdata(pdev);
+ misc_deregister(&rm->miscdev);
mbox_free_channel(gh_msgq_chan(&rm->msgq));
gh_msgq_remove(&rm->msgq);
kmem_cache_destroy(rm->cache);
diff --git a/drivers/virt/gunyah/vm_mgr.c b/drivers/virt/gunyah/vm_mgr.c
new file mode 100644
index 000000000000..0864dbd77e28
--- /dev/null
+++ b/drivers/virt/gunyah/vm_mgr.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All
rights reserved.
+ */
+
+#define pr_fmt(fmt) "gh_vm_mgr: " fmt
+
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/gunyah_rsc_mgr.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+
+#include <uapi/linux/gunyah.h>
+
+#include "vm_mgr.h"
+
+static __must_check struct gunyah_vm *gunyah_vm_alloc(struct
gh_rm_rpc *rm)
+{
+ struct gunyah_vm *ghvm;
+ int vmid;
+
+ vmid = gh_rm_alloc_vmid(rm, 0);
+ if (vmid < 0)
+ return ERR_PTR(vmid);
+
+ ghvm = kzalloc(sizeof(*ghvm), GFP_KERNEL);
+ if (!ghvm) {
+ gh_rm_dealloc_vmid(rm, vmid);
+ return ghvm;
return ERR_PTR(-ENOMEM);
Done.
+ }
+
+ get_gh_rm(rm);
+
+ ghvm->vmid = vmid;
+ ghvm->rm = rm;
+
+ return ghvm;
+}
+
+static long gh_vm_ioctl(struct file *filp, unsigned int cmd, unsigned
long arg)
+{
+ long r;
+
+ switch (cmd) {
+ default:
+ r = -ENOTTY;
+ break;
+ }
this function looks like dummy, why do we need this in this patch?
Refactored the patches to introduce when first ioctl is added.
+
+ return r;
+}
+
+static int gh_vm_release(struct inode *inode, struct file *filp)
+{
+ struct gunyah_vm *ghvm = filp->private_data;
+
+ put_gh_rm(ghvm->rm);
+ kfree(ghvm);
+ return 0;
+}
+
+static const struct file_operations gh_vm_fops = {
+ .unlocked_ioctl = gh_vm_ioctl,
+ .release = gh_vm_release,
+ .compat_ioctl = compat_ptr_ioctl,
+ .llseek = noop_llseek,
+};
+
+static long gh_dev_ioctl_create_vm(struct gh_rm *rm, unsigned long arg)
+{
+ struct gunyah_vm *ghvm;
+ struct file *file;
+ int fd, err;
+
+ /* arg reserved for future use. */
+ if (arg)
+ return -EINVAL;
Bit confused here, GH_CREATE_VM IOCTL does not take any arguments so why
is this arg reserved for future use. Are you going to change the ABI for
GH_CREATE_VM?
KVM uses the argument for architecture-specific VM flags. This series
only adds support for the "unauthenticated VM" type. I was thinking it
might be convenient to use this field to mux between the different
authentication types (zero would always mean "unauthenticated VM"). I've
not given a lot of thought to exact mechanics, but if I want to use in
the future, I think it should be reserved today to ensure there's no
backwards compatibility issues.
+
+ ghvm = gunyah_vm_alloc(rm);
+ if (IS_ERR_OR_NULL(ghvm))
+ return PTR_ERR(ghvm) ? : -ENOMEM;
+
+ fd = get_unused_fd_flags(O_CLOEXEC);
+ if (fd < 0) {
+ err = fd;
+ goto err_destroy_vm;
+ }
+
+ file = anon_inode_getfile("gunyah-vm", &gh_vm_fops, ghvm, O_RDWR);
+ if (IS_ERR(file)) {
+ err = PTR_ERR(file);
+ goto err_put_fd;
+ }
+
+ fd_install(fd, file);
+
+ return fd;
+
+err_put_fd:
+ put_unused_fd(fd);
+err_destroy_vm:
+ kfree(ghvm);
+ return err;
+}
+
+long gh_dev_vm_mgr_ioctl(struct gh_rm *rm, unsigned int cmd, unsigned
long arg)
+{
+ switch (cmd) {
+ case GH_CREATE_VM:
+ return gh_dev_ioctl_create_vm(rm, arg);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+EXPORT_SYMBOL_GPL(gh_dev_vm_mgr_ioctl);
+
diff --git a/drivers/virt/gunyah/vm_mgr.h b/drivers/virt/gunyah/vm_mgr.h
new file mode 100644
index 000000000000..e47f34de7f9e
--- /dev/null
+++ b/drivers/virt/gunyah/vm_mgr.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All
rights reserved.
+ */
+
+#ifndef _GH_PRIV_VM_MGR_H
+#define _GH_PRIV_VM_MGR_H
+
+#include <linux/gunyah_rsc_mgr.h>
+
+#include <uapi/linux/gunyah.h>
+
+long gh_dev_vm_mgr_ioctl(struct gh_rm *rm, unsigned int cmd, unsigned
long arg);
+
+struct gunyah_vm {
+ u16 vmid;
+ struct gh_rm_rpc *rm;
+};
+
+#endif
diff --git a/include/linux/gunyah_rsc_mgr.h
b/include/linux/gunyah_rsc_mgr.h
index be0bce5507b1..9a9a037b349a 100644
--- a/include/linux/gunyah_rsc_mgr.h
+++ b/include/linux/gunyah_rsc_mgr.h
@@ -17,6 +17,9 @@
struct gh_rm;
+void get_gh_rm(struct gh_rm *rm);
+void put_gh_rm(struct gh_rm *rm);
+
enum gh_rm_vm_status {
GH_RM_VM_STATUS_NO_STATE = 0,
GH_RM_VM_STATUS_INIT = 1,
diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h
new file mode 100644
index 000000000000..88a40d6e0b96
--- /dev/null
+++ b/include/uapi/linux/gunyah.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-only WITH Linux-syscall-note */
+/*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights
reserved.
+ */
+
+#ifndef _UAPI_LINUX_GUNYAH
+#define _UAPI_LINUX_GUNYAH
+
+/*
+ * Userspace interface for /dev/gunyah - gunyah based virtual machine
+ */
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define GH_IOCTL_TYPE 'G'
+
+/*
+ * ioctls for /dev/gunyah fds:
+ */
+#define GH_CREATE_VM _IO(GH_IOCTL_TYPE, 0x0) /* Returns a
Gunyah VM fd */
+
+#endif