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-rw-r--r--drivers/infiniband/core/Makefile2
-rw-r--r--drivers/infiniband/core/rdma_core.c46
-rw-r--r--drivers/infiniband/core/rdma_core.h5
-rw-r--r--drivers/infiniband/core/uverbs_ioctl.c364
-rw-r--r--include/rdma/ib_verbs.h2
-rw-r--r--include/rdma/uverbs_ioctl.h101
-rw-r--r--include/uapi/rdma/rdma_user_ioctl.h33
7 files changed, 543 insertions, 10 deletions
diff --git a/drivers/infiniband/core/Makefile b/drivers/infiniband/core/Makefile
index 920609a0872e..746756dc9877 100644
--- a/drivers/infiniband/core/Makefile
+++ b/drivers/infiniband/core/Makefile
@@ -32,4 +32,4 @@ ib_umad-y := user_mad.o
ib_ucm-y := ucm.o
ib_uverbs-y := uverbs_main.o uverbs_cmd.o uverbs_marshall.o \
- rdma_core.o uverbs_std_types.o
+ rdma_core.o uverbs_std_types.o uverbs_ioctl.o
diff --git a/drivers/infiniband/core/rdma_core.c b/drivers/infiniband/core/rdma_core.c
index 0fe8ef913387..2a2f002ac7cb 100644
--- a/drivers/infiniband/core/rdma_core.c
+++ b/drivers/infiniband/core/rdma_core.c
@@ -36,10 +36,56 @@
#include <rdma/uverbs_types.h>
#include <linux/rcupdate.h>
#include <rdma/uverbs_ioctl.h>
+#include <rdma/rdma_user_ioctl.h>
#include "uverbs.h"
#include "core_priv.h"
#include "rdma_core.h"
+int uverbs_ns_idx(u16 *id, unsigned int ns_count)
+{
+ int ret = (*id & UVERBS_ID_NS_MASK) >> UVERBS_ID_NS_SHIFT;
+
+ if (ret >= ns_count)
+ return -EINVAL;
+
+ *id &= ~UVERBS_ID_NS_MASK;
+ return ret;
+}
+
+const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
+ uint16_t object)
+{
+ const struct uverbs_root_spec *object_hash = ibdev->specs_root;
+ const struct uverbs_object_spec_hash *objects;
+ int ret = uverbs_ns_idx(&object, object_hash->num_buckets);
+
+ if (ret < 0)
+ return NULL;
+
+ objects = object_hash->object_buckets[ret];
+
+ if (object >= objects->num_objects)
+ return NULL;
+
+ return objects->objects[object];
+}
+
+const struct uverbs_method_spec *uverbs_get_method(const struct uverbs_object_spec *object,
+ uint16_t method)
+{
+ const struct uverbs_method_spec_hash *methods;
+ int ret = uverbs_ns_idx(&method, object->num_buckets);
+
+ if (ret < 0)
+ return NULL;
+
+ methods = object->method_buckets[ret];
+ if (method >= methods->num_methods)
+ return NULL;
+
+ return methods->methods[method];
+}
+
void uverbs_uobject_get(struct ib_uobject *uobject)
{
kref_get(&uobject->ref);
diff --git a/drivers/infiniband/core/rdma_core.h b/drivers/infiniband/core/rdma_core.h
index 9ed6ad0324c7..1efcf93238dd 100644
--- a/drivers/infiniband/core/rdma_core.h
+++ b/drivers/infiniband/core/rdma_core.h
@@ -43,6 +43,11 @@
#include <rdma/ib_verbs.h>
#include <linux/mutex.h>
+int uverbs_ns_idx(u16 *id, unsigned int ns_count);
+const struct uverbs_object_spec *uverbs_get_object(const struct ib_device *ibdev,
+ uint16_t object);
+const struct uverbs_method_spec *uverbs_get_method(const struct uverbs_object_spec *object,
+ uint16_t method);
/*
* These functions initialize the context and cleanups its uobjects.
* The context has a list of objects which is protected by a mutex
diff --git a/drivers/infiniband/core/uverbs_ioctl.c b/drivers/infiniband/core/uverbs_ioctl.c
new file mode 100644
index 000000000000..5286ad57d903
--- /dev/null
+++ b/drivers/infiniband/core/uverbs_ioctl.c
@@ -0,0 +1,364 @@
+/*
+ * Copyright (c) 2017, Mellanox Technologies inc. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses. You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials
+ * provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <rdma/rdma_user_ioctl.h>
+#include <rdma/uverbs_ioctl.h>
+#include "rdma_core.h"
+#include "uverbs.h"
+
+static int uverbs_process_attr(struct ib_device *ibdev,
+ struct ib_ucontext *ucontext,
+ const struct ib_uverbs_attr *uattr,
+ u16 attr_id,
+ const struct uverbs_attr_spec_hash *attr_spec_bucket,
+ struct uverbs_attr_bundle_hash *attr_bundle_h,
+ struct ib_uverbs_attr __user *uattr_ptr)
+{
+ const struct uverbs_attr_spec *spec;
+ struct uverbs_attr *e;
+ const struct uverbs_object_spec *object;
+ struct uverbs_obj_attr *o_attr;
+ struct uverbs_attr *elements = attr_bundle_h->attrs;
+
+ if (uattr->reserved)
+ return -EINVAL;
+
+ if (attr_id >= attr_spec_bucket->num_attrs) {
+ if (uattr->flags & UVERBS_ATTR_F_MANDATORY)
+ return -EINVAL;
+ else
+ return 0;
+ }
+
+ spec = &attr_spec_bucket->attrs[attr_id];
+ e = &elements[attr_id];
+ e->uattr = uattr_ptr;
+
+ switch (spec->type) {
+ case UVERBS_ATTR_TYPE_PTR_IN:
+ case UVERBS_ATTR_TYPE_PTR_OUT:
+ if (uattr->len < spec->len ||
+ (!(spec->flags & UVERBS_ATTR_SPEC_F_MIN_SZ) &&
+ uattr->len > spec->len))
+ return -EINVAL;
+
+ e->ptr_attr.data = uattr->data;
+ e->ptr_attr.len = uattr->len;
+ e->ptr_attr.flags = uattr->flags;
+ break;
+
+ case UVERBS_ATTR_TYPE_IDR:
+ if (uattr->data >> 32)
+ return -EINVAL;
+ /* fall through */
+ case UVERBS_ATTR_TYPE_FD:
+ if (uattr->len != 0 || !ucontext || uattr->data > INT_MAX)
+ return -EINVAL;
+
+ o_attr = &e->obj_attr;
+ object = uverbs_get_object(ibdev, spec->obj.obj_type);
+ if (!object)
+ return -EINVAL;
+ o_attr->type = object->type_attrs;
+
+ o_attr->id = (int)uattr->data;
+ o_attr->uobject = uverbs_get_uobject_from_context(
+ o_attr->type,
+ ucontext,
+ spec->obj.access,
+ o_attr->id);
+
+ if (IS_ERR(o_attr->uobject))
+ return PTR_ERR(o_attr->uobject);
+
+ if (spec->obj.access == UVERBS_ACCESS_NEW) {
+ u64 id = o_attr->uobject->id;
+
+ /* Copy the allocated id to the user-space */
+ if (put_user(id, &e->uattr->data)) {
+ uverbs_finalize_object(o_attr->uobject,
+ UVERBS_ACCESS_NEW,
+ false);
+ return -EFAULT;
+ }
+ }
+
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ set_bit(attr_id, attr_bundle_h->valid_bitmap);
+ return 0;
+}
+
+static int uverbs_uattrs_process(struct ib_device *ibdev,
+ struct ib_ucontext *ucontext,
+ const struct ib_uverbs_attr *uattrs,
+ size_t num_uattrs,
+ const struct uverbs_method_spec *method,
+ struct uverbs_attr_bundle *attr_bundle,
+ struct ib_uverbs_attr __user *uattr_ptr)
+{
+ size_t i;
+ int ret = 0;
+ int num_given_buckets = 0;
+
+ for (i = 0; i < num_uattrs; i++) {
+ const struct ib_uverbs_attr *uattr = &uattrs[i];
+ u16 attr_id = uattr->attr_id;
+ struct uverbs_attr_spec_hash *attr_spec_bucket;
+
+ ret = uverbs_ns_idx(&attr_id, method->num_buckets);
+ if (ret < 0) {
+ if (uattr->flags & UVERBS_ATTR_F_MANDATORY) {
+ uverbs_finalize_objects(attr_bundle,
+ method->attr_buckets,
+ num_given_buckets,
+ false);
+ return ret;
+ }
+ continue;
+ }
+
+ /*
+ * ret is the found ns, so increase num_given_buckets if
+ * necessary.
+ */
+ if (ret >= num_given_buckets)
+ num_given_buckets = ret + 1;
+
+ attr_spec_bucket = method->attr_buckets[ret];
+ ret = uverbs_process_attr(ibdev, ucontext, uattr, attr_id,
+ attr_spec_bucket, &attr_bundle->hash[ret],
+ uattr_ptr++);
+ if (ret) {
+ uverbs_finalize_objects(attr_bundle,
+ method->attr_buckets,
+ num_given_buckets,
+ false);
+ return ret;
+ }
+ }
+
+ return num_given_buckets;
+}
+
+static int uverbs_validate_kernel_mandatory(const struct uverbs_method_spec *method_spec,
+ struct uverbs_attr_bundle *attr_bundle)
+{
+ unsigned int i;
+
+ for (i = 0; i < attr_bundle->num_buckets; i++) {
+ struct uverbs_attr_spec_hash *attr_spec_bucket =
+ method_spec->attr_buckets[i];
+
+ if (!bitmap_subset(attr_spec_bucket->mandatory_attrs_bitmask,
+ attr_bundle->hash[i].valid_bitmap,
+ attr_spec_bucket->num_attrs))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int uverbs_handle_method(struct ib_uverbs_attr __user *uattr_ptr,
+ const struct ib_uverbs_attr *uattrs,
+ size_t num_uattrs,
+ struct ib_device *ibdev,
+ struct ib_uverbs_file *ufile,
+ const struct uverbs_method_spec *method_spec,
+ struct uverbs_attr_bundle *attr_bundle)
+{
+ int ret;
+ int finalize_ret;
+ int num_given_buckets;
+
+ num_given_buckets = uverbs_uattrs_process(ibdev, ufile->ucontext, uattrs,
+ num_uattrs, method_spec,
+ attr_bundle, uattr_ptr);
+ if (num_given_buckets <= 0)
+ return -EINVAL;
+
+ attr_bundle->num_buckets = num_given_buckets;
+ ret = uverbs_validate_kernel_mandatory(method_spec, attr_bundle);
+ if (ret)
+ goto cleanup;
+
+ ret = method_spec->handler(ibdev, ufile, attr_bundle);
+cleanup:
+ finalize_ret = uverbs_finalize_objects(attr_bundle,
+ method_spec->attr_buckets,
+ attr_bundle->num_buckets,
+ !ret);
+
+ return ret ? ret : finalize_ret;
+}
+
+#define UVERBS_OPTIMIZE_USING_STACK_SZ 256
+static long ib_uverbs_cmd_verbs(struct ib_device *ib_dev,
+ struct ib_uverbs_file *file,
+ struct ib_uverbs_ioctl_hdr *hdr,
+ void __user *buf)
+{
+ const struct uverbs_object_spec *object_spec;
+ const struct uverbs_method_spec *method_spec;
+ long err = 0;
+ unsigned int i;
+ struct {
+ struct ib_uverbs_attr *uattrs;
+ struct uverbs_attr_bundle *uverbs_attr_bundle;
+ } *ctx = NULL;
+ struct uverbs_attr *curr_attr;
+ unsigned long *curr_bitmap;
+ size_t ctx_size;
+#ifdef UVERBS_OPTIMIZE_USING_STACK_SZ
+ uintptr_t data[UVERBS_OPTIMIZE_USING_STACK_SZ / sizeof(uintptr_t)];
+#endif
+
+ if (hdr->reserved)
+ return -EINVAL;
+
+ object_spec = uverbs_get_object(ib_dev, hdr->object_id);
+ if (!object_spec)
+ return -EOPNOTSUPP;
+
+ method_spec = uverbs_get_method(object_spec, hdr->method_id);
+ if (!method_spec)
+ return -EOPNOTSUPP;
+
+ if ((method_spec->flags & UVERBS_ACTION_FLAG_CREATE_ROOT) ^ !file->ucontext)
+ return -EINVAL;
+
+ ctx_size = sizeof(*ctx) +
+ sizeof(struct uverbs_attr_bundle) +
+ sizeof(struct uverbs_attr_bundle_hash) * method_spec->num_buckets +
+ sizeof(*ctx->uattrs) * hdr->num_attrs +
+ sizeof(*ctx->uverbs_attr_bundle->hash[0].attrs) *
+ method_spec->num_child_attrs +
+ sizeof(*ctx->uverbs_attr_bundle->hash[0].valid_bitmap) *
+ (method_spec->num_child_attrs / BITS_PER_LONG +
+ method_spec->num_buckets);
+
+#ifdef UVERBS_OPTIMIZE_USING_STACK_SZ
+ if (ctx_size <= UVERBS_OPTIMIZE_USING_STACK_SZ)
+ ctx = (void *)data;
+
+ if (!ctx)
+#endif
+ ctx = kmalloc(ctx_size, GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->uverbs_attr_bundle = (void *)ctx + sizeof(*ctx);
+ ctx->uattrs = (void *)(ctx->uverbs_attr_bundle + 1) +
+ (sizeof(ctx->uverbs_attr_bundle->hash[0]) *
+ method_spec->num_buckets);
+ curr_attr = (void *)(ctx->uattrs + hdr->num_attrs);
+ curr_bitmap = (void *)(curr_attr + method_spec->num_child_attrs);
+
+ /*
+ * We just fill the pointers and num_attrs here. The data itself will be
+ * filled at a later stage (uverbs_process_attr)
+ */
+ for (i = 0; i < method_spec->num_buckets; i++) {
+ unsigned int curr_num_attrs = method_spec->attr_buckets[i]->num_attrs;
+
+ ctx->uverbs_attr_bundle->hash[i].attrs = curr_attr;
+ curr_attr += curr_num_attrs;
+ ctx->uverbs_attr_bundle->hash[i].num_attrs = curr_num_attrs;
+ ctx->uverbs_attr_bundle->hash[i].valid_bitmap = curr_bitmap;
+ bitmap_zero(curr_bitmap, curr_num_attrs);
+ curr_bitmap += BITS_TO_LONGS(curr_num_attrs);
+ }
+
+ err = copy_from_user(ctx->uattrs, buf,
+ sizeof(*ctx->uattrs) * hdr->num_attrs);
+ if (err) {
+ err = -EFAULT;
+ goto out;
+ }
+
+ err = uverbs_handle_method(buf, ctx->uattrs, hdr->num_attrs, ib_dev,
+ file, method_spec, ctx->uverbs_attr_bundle);
+out:
+#ifdef UVERBS_OPTIMIZE_USING_STACK_SZ
+ if (ctx_size > UVERBS_OPTIMIZE_USING_STACK_SZ)
+#endif
+ kfree(ctx);
+ return err;
+}
+
+#define IB_UVERBS_MAX_CMD_SZ 4096
+
+long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ struct ib_uverbs_file *file = filp->private_data;
+ struct ib_uverbs_ioctl_hdr __user *user_hdr =
+ (struct ib_uverbs_ioctl_hdr __user *)arg;
+ struct ib_uverbs_ioctl_hdr hdr;
+ struct ib_device *ib_dev;
+ int srcu_key;
+ long err;
+
+ srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
+ ib_dev = srcu_dereference(file->device->ib_dev,
+ &file->device->disassociate_srcu);
+ if (!ib_dev) {
+ err = -EIO;
+ goto out;
+ }
+
+ if (cmd == RDMA_VERBS_IOCTL) {
+ err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
+
+ if (err || hdr.length > IB_UVERBS_MAX_CMD_SZ ||
+ hdr.length != sizeof(hdr) + hdr.num_attrs * sizeof(struct ib_uverbs_attr)) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (hdr.reserved) {
+ err = -EOPNOTSUPP;
+ goto out;
+ }
+
+ err = ib_uverbs_cmd_verbs(ib_dev, file, &hdr,
+ (__user void *)arg + sizeof(hdr));
+ } else {
+ err = -ENOIOCTLCMD;
+ }
+out:
+ srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
+
+ return err;
+}
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 1b4bb8743969..e6df68048517 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2348,6 +2348,8 @@ struct ib_device {
void (*get_dev_fw_str)(struct ib_device *, char *str);
const struct cpumask *(*get_vector_affinity)(struct ib_device *ibdev,
int comp_vector);
+
+ struct uverbs_root_spec *specs_root;
};
struct ib_client {
diff --git a/include/rdma/uverbs_ioctl.h b/include/rdma/uverbs_ioctl.h
index d3ec02b7d937..f83f56329761 100644
--- a/include/rdma/uverbs_ioctl.h
+++ b/include/rdma/uverbs_ioctl.h
@@ -43,6 +43,8 @@
enum uverbs_attr_type {
UVERBS_ATTR_TYPE_NA,
+ UVERBS_ATTR_TYPE_PTR_IN,
+ UVERBS_ATTR_TYPE_PTR_OUT,
UVERBS_ATTR_TYPE_IDR,
UVERBS_ATTR_TYPE_FD,
};
@@ -54,29 +56,110 @@ enum uverbs_obj_access {
UVERBS_ACCESS_DESTROY
};
+enum {
+ UVERBS_ATTR_SPEC_F_MANDATORY = 1U << 0,
+ /* Support extending attributes by length */
+ UVERBS_ATTR_SPEC_F_MIN_SZ = 1U << 1,
+};
+
struct uverbs_attr_spec {
enum uverbs_attr_type type;
- struct {
- /*
- * higher bits mean the namespace and lower bits mean
- * the type id within the namespace.
- */
- u16 obj_type;
- u8 access;
- } obj;
+ union {
+ u16 len;
+ struct {
+ /*
+ * higher bits mean the namespace and lower bits mean
+ * the type id within the namespace.
+ */
+ u16 obj_type;
+ u8 access;
+ } obj;
+ };
+ /* Combination of bits from enum UVERBS_ATTR_SPEC_F_XXXX */
+ u8 flags;
};
struct uverbs_attr_spec_hash {
size_t num_attrs;
+ unsigned long *mandatory_attrs_bitmask;
struct uverbs_attr_spec attrs[0];
};
+struct uverbs_attr_bundle;
+struct ib_uverbs_file;
+
+enum {
+ /*
+ * Action marked with this flag creates a context (or root for all
+ * objects).
+ */
+ UVERBS_ACTION_FLAG_CREATE_ROOT = 1U << 0,
+};
+
+struct uverbs_method_spec {
+ /* Combination of bits from enum UVERBS_ACTION_FLAG_XXXX */
+ u32 flags;
+ size_t num_buckets;
+ size_t num_child_attrs;
+ int (*handler)(struct ib_device *ib_dev, struct ib_uverbs_file *ufile,
+ struct uverbs_attr_bundle *ctx);
+ struct uverbs_attr_spec_hash *attr_buckets[0];
+};
+
+struct uverbs_method_spec_hash {
+ size_t num_methods;
+ struct uverbs_method_spec *methods[0];
+};
+
+struct uverbs_object_spec {
+ const struct uverbs_obj_type *type_attrs;
+ size_t num_buckets;
+ struct uverbs_method_spec_hash *method_buckets[0];
+};
+
+struct uverbs_object_spec_hash {
+ size_t num_objects;
+ struct uverbs_object_spec *objects[0];
+};
+
+struct uverbs_root_spec {
+ size_t num_buckets;
+ struct uverbs_object_spec_hash *object_buckets[0];
+};
+
+/* =================================================
+ * Parsing infrastructure
+ * =================================================
+ */
+
+struct uverbs_ptr_attr {
+ union {
+ u64 data;
+ void __user *ptr;
+ };
+ u16 len;
+ /* Combination of bits from enum UVERBS_ATTR_F_XXXX */
+ u16 flags;
+};
+
struct uverbs_obj_attr {
+ /* pointer to the kernel descriptor -> type, access, etc */
+ const struct uverbs_obj_type *type;
struct ib_uobject *uobject;
+ /* fd or id in idr of this object */
+ int id;
};
struct uverbs_attr {
- struct uverbs_obj_attr obj_attr;
+ /*
+ * pointer to the user-space given attribute, in order to write the
+ * new uobject's id or update flags.
+ */
+ struct ib_uverbs_attr __user *uattr;
+ union {
+ struct uverbs_ptr_attr ptr_attr;
+ struct uverbs_obj_attr obj_attr;
+ };
};
struct uverbs_attr_bundle_hash {
diff --git a/include/uapi/rdma/rdma_user_ioctl.h b/include/uapi/rdma/rdma_user_ioctl.h
index 9388125ad51b..165a27e969d5 100644
--- a/include/uapi/rdma/rdma_user_ioctl.h
+++ b/include/uapi/rdma/rdma_user_ioctl.h
@@ -43,6 +43,39 @@
/* Legacy name, for user space application which already use it */
#define IB_IOCTL_MAGIC RDMA_IOCTL_MAGIC
+#define RDMA_VERBS_IOCTL \
+ _IOWR(RDMA_IOCTL_MAGIC, 1, struct ib_uverbs_ioctl_hdr)
+
+#define UVERBS_ID_NS_MASK 0xF000
+#define UVERBS_ID_NS_SHIFT 12
+
+enum {
+ /* User input */
+ UVERBS_ATTR_F_MANDATORY = 1U << 0,
+ /*
+ * Valid output bit should be ignored and considered set in
+ * mandatory fields. This bit is kernel output.
+ */
+ UVERBS_ATTR_F_VALID_OUTPUT = 1U << 1,
+};
+
+struct ib_uverbs_attr {
+ __u16 attr_id; /* command specific type attribute */
+ __u16 len; /* only for pointers */
+ __u16 flags; /* combination of UVERBS_ATTR_F_XXXX */
+ __u16 reserved;
+ __u64 data; /* ptr to command, inline data or idr/fd */
+};
+
+struct ib_uverbs_ioctl_hdr {
+ __u16 length;
+ __u16 object_id;
+ __u16 method_id;
+ __u16 num_attrs;
+ __u64 reserved;
+ struct ib_uverbs_attr attrs[0];
+};
+
/*
* General blocks assignments
* It is closed on purpose do not expose it it user space
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.