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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/xen/xenfs
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/xen/xenfs')
-rw-r--r--drivers/xen/xenfs/Makefile5
-rw-r--r--drivers/xen/xenfs/super.c101
-rw-r--r--drivers/xen/xenfs/xenfs.h9
-rw-r--r--drivers/xen/xenfs/xenstored.c69
-rw-r--r--drivers/xen/xenfs/xensyms.c152
5 files changed, 336 insertions, 0 deletions
diff --git a/drivers/xen/xenfs/Makefile b/drivers/xen/xenfs/Makefile
new file mode 100644
index 000000000..1a83010dd
--- /dev/null
+++ b/drivers/xen/xenfs/Makefile
@@ -0,0 +1,5 @@
+obj-$(CONFIG_XENFS) += xenfs.o
+
+xenfs-y = super.o
+xenfs-$(CONFIG_XEN_DOM0) += xenstored.o
+xenfs-$(CONFIG_XEN_SYMS) += xensyms.o
diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c
new file mode 100644
index 000000000..71ddfb4cf
--- /dev/null
+++ b/drivers/xen/xenfs/super.c
@@ -0,0 +1,101 @@
+/*
+ * xenfs.c - a filesystem for passing info between the a domain and
+ * the hypervisor.
+ *
+ * 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
+ * and /proc/xen compatibility mount point.
+ * Turned xenfs into a loadable module.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/magic.h>
+
+#include <xen/xen.h>
+#include <xen/xenbus.h>
+
+#include "xenfs.h"
+#include "../privcmd.h"
+
+#include <asm/xen/hypervisor.h>
+
+MODULE_DESCRIPTION("Xen filesystem");
+MODULE_LICENSE("GPL");
+
+static ssize_t capabilities_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ char *tmp = "";
+
+ if (xen_initial_domain())
+ tmp = "control_d\n";
+
+ return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp));
+}
+
+static const struct file_operations capabilities_file_ops = {
+ .read = capabilities_read,
+ .llseek = default_llseek,
+};
+
+static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ static const struct tree_descr xenfs_files[] = {
+ [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+ {""},
+ };
+
+ static const struct tree_descr xenfs_init_files[] = {
+ [2] = { "xenbus", &xen_xenbus_fops, S_IRUSR|S_IWUSR },
+ { "capabilities", &capabilities_file_ops, S_IRUGO },
+ { "privcmd", &xen_privcmd_fops, S_IRUSR|S_IWUSR },
+ { "xsd_kva", &xsd_kva_file_ops, S_IRUSR|S_IWUSR},
+ { "xsd_port", &xsd_port_file_ops, S_IRUSR|S_IWUSR},
+#ifdef CONFIG_XEN_SYMS
+ { "xensyms", &xensyms_ops, S_IRUSR},
+#endif
+ {""},
+ };
+
+ return simple_fill_super(sb, XENFS_SUPER_MAGIC,
+ xen_initial_domain() ? xenfs_init_files : xenfs_files);
+}
+
+static struct dentry *xenfs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data)
+{
+ return mount_single(fs_type, flags, data, xenfs_fill_super);
+}
+
+static struct file_system_type xenfs_type = {
+ .owner = THIS_MODULE,
+ .name = "xenfs",
+ .mount = xenfs_mount,
+ .kill_sb = kill_litter_super,
+};
+MODULE_ALIAS_FS("xenfs");
+
+static int __init xenfs_init(void)
+{
+ if (xen_domain())
+ return register_filesystem(&xenfs_type);
+
+ return 0;
+}
+
+static void __exit xenfs_exit(void)
+{
+ if (xen_domain())
+ unregister_filesystem(&xenfs_type);
+}
+
+module_init(xenfs_init);
+module_exit(xenfs_exit);
+
diff --git a/drivers/xen/xenfs/xenfs.h b/drivers/xen/xenfs/xenfs.h
new file mode 100644
index 000000000..cfe4874b8
--- /dev/null
+++ b/drivers/xen/xenfs/xenfs.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _XENFS_XENBUS_H
+#define _XENFS_XENBUS_H
+
+extern const struct file_operations xsd_kva_file_ops;
+extern const struct file_operations xsd_port_file_ops;
+extern const struct file_operations xensyms_ops;
+
+#endif /* _XENFS_XENBUS_H */
diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c
new file mode 100644
index 000000000..f59235f9f
--- /dev/null
+++ b/drivers/xen/xenfs/xenstored.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+
+#include <xen/page.h>
+#include <xen/xenbus.h>
+
+#include "xenfs.h"
+
+static ssize_t xsd_read(struct file *file, char __user *buf,
+ size_t size, loff_t *off)
+{
+ const char *str = (const char *)file->private_data;
+ return simple_read_from_buffer(buf, size, off, str, strlen(str));
+}
+
+static int xsd_release(struct inode *inode, struct file *file)
+{
+ kfree(file->private_data);
+ return 0;
+}
+
+static int xsd_kva_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p",
+ xen_store_interface);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ size_t size = vma->vm_end - vma->vm_start;
+
+ if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0))
+ return -EINVAL;
+
+ if (remap_pfn_range(vma, vma->vm_start,
+ virt_to_pfn(xen_store_interface),
+ size, vma->vm_page_prot))
+ return -EAGAIN;
+
+ return 0;
+}
+
+const struct file_operations xsd_kva_file_ops = {
+ .open = xsd_kva_open,
+ .mmap = xsd_kva_mmap,
+ .read = xsd_read,
+ .release = xsd_release,
+};
+
+static int xsd_port_open(struct inode *inode, struct file *file)
+{
+ file->private_data = (void *)kasprintf(GFP_KERNEL, "%d",
+ xen_store_evtchn);
+ if (!file->private_data)
+ return -ENOMEM;
+ return 0;
+}
+
+const struct file_operations xsd_port_file_ops = {
+ .open = xsd_port_open,
+ .read = xsd_read,
+ .release = xsd_release,
+};
diff --git a/drivers/xen/xenfs/xensyms.c b/drivers/xen/xenfs/xensyms.c
new file mode 100644
index 000000000..c6c73a33c
--- /dev/null
+++ b/drivers/xen/xenfs/xensyms.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/seq_file.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/slab.h>
+#include <xen/interface/platform.h>
+#include <asm/xen/hypercall.h>
+#include <xen/xen-ops.h>
+#include "xenfs.h"
+
+
+#define XEN_KSYM_NAME_LEN 127 /* Hypervisor may have different name length */
+
+struct xensyms {
+ struct xen_platform_op op;
+ char *name;
+ uint32_t namelen;
+};
+
+/* Grab next output page from the hypervisor */
+static int xensyms_next_sym(struct xensyms *xs)
+{
+ int ret;
+ struct xenpf_symdata *symdata = &xs->op.u.symdata;
+ uint64_t symnum;
+
+ memset(xs->name, 0, xs->namelen);
+ symdata->namelen = xs->namelen;
+
+ symnum = symdata->symnum;
+
+ ret = HYPERVISOR_platform_op(&xs->op);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * If hypervisor's symbol didn't fit into the buffer then allocate
+ * a larger buffer and try again.
+ */
+ if (unlikely(symdata->namelen > xs->namelen)) {
+ kfree(xs->name);
+
+ xs->namelen = symdata->namelen;
+ xs->name = kzalloc(xs->namelen, GFP_KERNEL);
+ if (!xs->name)
+ return -ENOMEM;
+
+ set_xen_guest_handle(symdata->name, xs->name);
+ symdata->symnum--; /* Rewind */
+
+ ret = HYPERVISOR_platform_op(&xs->op);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (symdata->symnum == symnum)
+ /* End of symbols */
+ return 1;
+
+ return 0;
+}
+
+static void *xensyms_start(struct seq_file *m, loff_t *pos)
+{
+ struct xensyms *xs = (struct xensyms *)m->private;
+
+ xs->op.u.symdata.symnum = *pos;
+
+ if (xensyms_next_sym(xs))
+ return NULL;
+
+ return m->private;
+}
+
+static void *xensyms_next(struct seq_file *m, void *p, loff_t *pos)
+{
+ struct xensyms *xs = (struct xensyms *)m->private;
+
+ xs->op.u.symdata.symnum = ++(*pos);
+
+ if (xensyms_next_sym(xs))
+ return NULL;
+
+ return p;
+}
+
+static int xensyms_show(struct seq_file *m, void *p)
+{
+ struct xensyms *xs = (struct xensyms *)m->private;
+ struct xenpf_symdata *symdata = &xs->op.u.symdata;
+
+ seq_printf(m, "%016llx %c %s\n", symdata->address,
+ symdata->type, xs->name);
+
+ return 0;
+}
+
+static void xensyms_stop(struct seq_file *m, void *p)
+{
+}
+
+static const struct seq_operations xensyms_seq_ops = {
+ .start = xensyms_start,
+ .next = xensyms_next,
+ .show = xensyms_show,
+ .stop = xensyms_stop,
+};
+
+static int xensyms_open(struct inode *inode, struct file *file)
+{
+ struct seq_file *m;
+ struct xensyms *xs;
+ int ret;
+
+ ret = seq_open_private(file, &xensyms_seq_ops,
+ sizeof(struct xensyms));
+ if (ret)
+ return ret;
+
+ m = file->private_data;
+ xs = (struct xensyms *)m->private;
+
+ xs->namelen = XEN_KSYM_NAME_LEN + 1;
+ xs->name = kzalloc(xs->namelen, GFP_KERNEL);
+ if (!xs->name) {
+ seq_release_private(inode, file);
+ return -ENOMEM;
+ }
+ set_xen_guest_handle(xs->op.u.symdata.name, xs->name);
+ xs->op.cmd = XENPF_get_symbol;
+ xs->op.u.symdata.namelen = xs->namelen;
+
+ return 0;
+}
+
+static int xensyms_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = file->private_data;
+ struct xensyms *xs = (struct xensyms *)m->private;
+
+ kfree(xs->name);
+ return seq_release_private(inode, file);
+}
+
+const struct file_operations xensyms_ops = {
+ .open = xensyms_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = xensyms_release
+};