On 3/3/23 7:06 PM, 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>
One suggestion to move some code here. And a few other minor
things.
-Alex
---
.../userspace-api/ioctl/ioctl-number.rst | 1 +
drivers/virt/gunyah/Makefile | 2 +-
drivers/virt/gunyah/rsc_mgr.c | 38 +++++-
drivers/virt/gunyah/vm_mgr.c | 116 ++++++++++++++++++
drivers/virt/gunyah/vm_mgr.h | 23 ++++
include/uapi/linux/gunyah.h | 23 ++++
6 files changed, 201 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 0a1882e296ae..2513324ae7be 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 67813c9a52db..d7ce692d0067 100644
--- a/drivers/virt/gunyah/rsc_mgr.c
+++ b/drivers/virt/gunyah/rsc_mgr.c
@@ -15,8 +15,10 @@
#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)
@@ -129,6 +131,7 @@ struct gh_rm_connection {
* @cache: cache for allocating Tx messages
* @send_lock: synchronization to allow only one request to be sent at a time
* @nh: notifier chain for clients interested in RM notification messages
+ * @miscdev: /dev/gunyah
*/
struct gh_rm {
struct device *dev;
@@ -145,6 +148,8 @@ struct gh_rm {
struct kmem_cache *cache;
struct mutex send_lock;
struct blocking_notifier_head nh;
+
+ struct miscdevice miscdev;
};
/**
@@ -593,6 +598,21 @@ void gh_rm_put(struct gh_rm *rm)
}
EXPORT_SYMBOL_GPL(gh_rm_put);
I feel like /dev/gunyah code would more appropriately be found
in "vm_mgr.c". All gh_dev_ioctl() does is call the function
defined there, and it's therefore a VM-oriented rather than
resource-oriented device.
+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,
struct gh_resource *ghrsc)
{
@@ -651,7 +671,22 @@ 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;
@@ -661,6 +696,7 @@ 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..dbacf36af72d
--- /dev/null
+++ b/drivers/virt/gunyah/vm_mgr.c
@@ -0,0 +1,116 @@
+// 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 void gh_vm_free(struct work_struct *work)
+{
+ struct gh_vm *ghvm = container_of(work, struct gh_vm, free_work);
+ int ret;
+
+ ret = gh_rm_dealloc_vmid(ghvm->rm, ghvm->vmid);
+ if (ret)
+ pr_warn("Failed to deallocate vmid: %d\n", ret);
+
+ put_gh_rm(ghvm->rm);
+ kfree(ghvm);
+}
+
+static __must_check struct gh_vm *gh_vm_alloc(struct gh_rm *rm)
+{
+ struct gh_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 ERR_PTR(-ENOMEM);
+ }
+
+ ghvm->parent = gh_rm_get(rm);
+ ghvm->vmid = vmid;
+ ghvm->rm = rm;
+
+ INIT_WORK(&ghvm->free_work, gh_vm_free);
+
+ return ghvm;
+}
+
+static int gh_vm_release(struct inode *inode, struct file *filp)
+{
+ struct gh_vm *ghvm = filp->private_data;
+
+ /* VM will be reset and make RM calls which can interruptible sleep.
+ * Defer to a work so this thread can receive signal.
+ */
+ schedule_work(&ghvm->free_work);
+ return 0;
+}
+
+static const struct file_operations gh_vm_fops = {
+ .release = gh_vm_release,
+ .llseek = noop_llseek,
+};
+
+static long gh_dev_ioctl_create_vm(struct gh_rm *rm, unsigned long arg)
+{
+ struct gh_vm *ghvm;
+ struct file *file;
+ int fd, err;
+
+ /* arg reserved for future use. */
Do you have a clear idea of how this might be used in the future?
I was thinking you could silently ignore the argument value, but
I suppose if it *does* get used in the future, you want the caller
to know it's being ignored. (Is that right?)
+ if (arg)
+ return -EINVAL;
+
+ ghvm = gh_vm_alloc(rm);
+ if (IS_ERR(ghvm))
+ return PTR_ERR(ghvm);
+
+ 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:
+ gh_vm_free(&ghvm->free_work);
+ 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;
+ }
+}
diff --git a/drivers/virt/gunyah/vm_mgr.h b/drivers/virt/gunyah/vm_mgr.h
new file mode 100644
index 000000000000..4b22fbcac91c
--- /dev/null
+++ b/drivers/virt/gunyah/vm_mgr.h
@@ -0,0 +1,23 @@
+/* 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
Maybe _GH_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 gh_vm {
+ u16 vmid;
+ struct gh_rm *rm;
+ struct device *parent;
+
+ struct work_struct free_work;
+};
+
+#endif
diff --git a/include/uapi/linux/gunyah.h b/include/uapi/linux/gunyah.h
new file mode 100644
index 000000000000..10ba32d2b0a6
--- /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) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _UAPI_LINUX_GUNYAH
+#define _UAPI_LINUX_GUNYAH
Use _UAPI_LINUX_GUNYAH_H
+
+/*
+ * 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
