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|
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*/
/**
* DOC: Enclave lifetime management driver for Nitro Enclaves (NE).
* Nitro is a hypervisor that has been developed by Amazon.
*/
#include <linux/anon_inodes.h>
#include <linux/capability.h>
#include <linux/cpu.h>
#include <linux/device.h>
#include <linux/file.h>
#include <linux/hugetlb.h>
#include <linux/limits.h>
#include <linux/list.h>
#include <linux/miscdevice.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/nitro_enclaves.h>
#include <linux/pci.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <uapi/linux/vm_sockets.h>
#include "ne_misc_dev.h"
#include "ne_pci_dev.h"
/**
* NE_CPUS_SIZE - Size for max 128 CPUs, for now, in a cpu-list string, comma
* separated. The NE CPU pool includes CPUs from a single NUMA
* node.
*/
#define NE_CPUS_SIZE (512)
/**
* NE_EIF_LOAD_OFFSET - The offset where to copy the Enclave Image Format (EIF)
* image in enclave memory.
*/
#define NE_EIF_LOAD_OFFSET (8 * 1024UL * 1024UL)
/**
* NE_MIN_ENCLAVE_MEM_SIZE - The minimum memory size an enclave can be launched
* with.
*/
#define NE_MIN_ENCLAVE_MEM_SIZE (64 * 1024UL * 1024UL)
/**
* NE_MIN_MEM_REGION_SIZE - The minimum size of an enclave memory region.
*/
#define NE_MIN_MEM_REGION_SIZE (2 * 1024UL * 1024UL)
/**
* NE_PARENT_VM_CID - The CID for the vsock device of the primary / parent VM.
*/
#define NE_PARENT_VM_CID (3)
static long ne_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
static const struct file_operations ne_fops = {
.owner = THIS_MODULE,
.llseek = noop_llseek,
.unlocked_ioctl = ne_ioctl,
};
static struct miscdevice ne_misc_dev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "nitro_enclaves",
.fops = &ne_fops,
.mode = 0660,
};
struct ne_devs ne_devs = {
.ne_misc_dev = &ne_misc_dev,
};
/*
* TODO: Update logic to create new sysfs entries instead of using
* a kernel parameter e.g. if multiple sysfs files needed.
*/
static int ne_set_kernel_param(const char *val, const struct kernel_param *kp);
static const struct kernel_param_ops ne_cpu_pool_ops = {
.get = param_get_string,
.set = ne_set_kernel_param,
};
static char ne_cpus[NE_CPUS_SIZE];
static struct kparam_string ne_cpus_arg = {
.maxlen = sizeof(ne_cpus),
.string = ne_cpus,
};
module_param_cb(ne_cpus, &ne_cpu_pool_ops, &ne_cpus_arg, 0644);
/* https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html#cpu-lists */
MODULE_PARM_DESC(ne_cpus, "<cpu-list> - CPU pool used for Nitro Enclaves");
/**
* struct ne_cpu_pool - CPU pool used for Nitro Enclaves.
* @avail_threads_per_core: Available full CPU cores to be dedicated to
* enclave(s). The cpumasks from the array, indexed
* by core id, contain all the threads from the
* available cores, that are not set for created
* enclave(s). The full CPU cores are part of the
* NE CPU pool.
* @mutex: Mutex for the access to the NE CPU pool.
* @nr_parent_vm_cores : The size of the available threads per core array.
* The total number of CPU cores available on the
* primary / parent VM.
* @nr_threads_per_core: The number of threads that a full CPU core has.
* @numa_node: NUMA node of the CPUs in the pool.
*/
struct ne_cpu_pool {
cpumask_var_t *avail_threads_per_core;
struct mutex mutex;
unsigned int nr_parent_vm_cores;
unsigned int nr_threads_per_core;
int numa_node;
};
static struct ne_cpu_pool ne_cpu_pool;
/**
* ne_check_enclaves_created() - Verify if at least one enclave has been created.
* @void: No parameters provided.
*
* Context: Process context.
* Return:
* * True if at least one enclave is created.
* * False otherwise.
*/
static bool ne_check_enclaves_created(void)
{
struct ne_pci_dev *ne_pci_dev = ne_devs.ne_pci_dev;
bool ret = false;
if (!ne_pci_dev)
return ret;
mutex_lock(&ne_pci_dev->enclaves_list_mutex);
if (!list_empty(&ne_pci_dev->enclaves_list))
ret = true;
mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
return ret;
}
/**
* ne_setup_cpu_pool() - Set the NE CPU pool after handling sanity checks such
* as not sharing CPU cores with the primary / parent VM
* or not using CPU 0, which should remain available for
* the primary / parent VM. Offline the CPUs from the
* pool after the checks passed.
* @ne_cpu_list: The CPU list used for setting NE CPU pool.
*
* Context: Process context.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_setup_cpu_pool(const char *ne_cpu_list)
{
int core_id = -1;
unsigned int cpu = 0;
cpumask_var_t cpu_pool;
unsigned int cpu_sibling = 0;
unsigned int i = 0;
int numa_node = -1;
int rc = -EINVAL;
if (!zalloc_cpumask_var(&cpu_pool, GFP_KERNEL))
return -ENOMEM;
mutex_lock(&ne_cpu_pool.mutex);
rc = cpulist_parse(ne_cpu_list, cpu_pool);
if (rc < 0) {
pr_err("%s: Error in cpulist parse [rc=%d]\n", ne_misc_dev.name, rc);
goto free_pool_cpumask;
}
cpu = cpumask_any(cpu_pool);
if (cpu >= nr_cpu_ids) {
pr_err("%s: No CPUs available in CPU pool\n", ne_misc_dev.name);
rc = -EINVAL;
goto free_pool_cpumask;
}
/*
* Check if the CPUs are online, to further get info about them
* e.g. numa node, core id, siblings.
*/
for_each_cpu(cpu, cpu_pool)
if (cpu_is_offline(cpu)) {
pr_err("%s: CPU %d is offline, has to be online to get its metadata\n",
ne_misc_dev.name, cpu);
rc = -EINVAL;
goto free_pool_cpumask;
}
/*
* Check if the CPUs from the NE CPU pool are from the same NUMA node.
*/
for_each_cpu(cpu, cpu_pool)
if (numa_node < 0) {
numa_node = cpu_to_node(cpu);
if (numa_node < 0) {
pr_err("%s: Invalid NUMA node %d\n",
ne_misc_dev.name, numa_node);
rc = -EINVAL;
goto free_pool_cpumask;
}
} else {
if (numa_node != cpu_to_node(cpu)) {
pr_err("%s: CPUs with different NUMA nodes\n",
ne_misc_dev.name);
rc = -EINVAL;
goto free_pool_cpumask;
}
}
/*
* Check if CPU 0 and its siblings are included in the provided CPU pool
* They should remain available for the primary / parent VM.
*/
if (cpumask_test_cpu(0, cpu_pool)) {
pr_err("%s: CPU 0 has to remain available\n", ne_misc_dev.name);
rc = -EINVAL;
goto free_pool_cpumask;
}
for_each_cpu(cpu_sibling, topology_sibling_cpumask(0)) {
if (cpumask_test_cpu(cpu_sibling, cpu_pool)) {
pr_err("%s: CPU sibling %d for CPU 0 is in CPU pool\n",
ne_misc_dev.name, cpu_sibling);
rc = -EINVAL;
goto free_pool_cpumask;
}
}
/*
* Check if CPU siblings are included in the provided CPU pool. The
* expectation is that full CPU cores are made available in the CPU pool
* for enclaves.
*/
for_each_cpu(cpu, cpu_pool) {
for_each_cpu(cpu_sibling, topology_sibling_cpumask(cpu)) {
if (!cpumask_test_cpu(cpu_sibling, cpu_pool)) {
pr_err("%s: CPU %d is not in CPU pool\n",
ne_misc_dev.name, cpu_sibling);
rc = -EINVAL;
goto free_pool_cpumask;
}
}
}
/* Calculate the number of threads from a full CPU core. */
cpu = cpumask_any(cpu_pool);
for_each_cpu(cpu_sibling, topology_sibling_cpumask(cpu))
ne_cpu_pool.nr_threads_per_core++;
ne_cpu_pool.nr_parent_vm_cores = nr_cpu_ids / ne_cpu_pool.nr_threads_per_core;
ne_cpu_pool.avail_threads_per_core = kcalloc(ne_cpu_pool.nr_parent_vm_cores,
sizeof(*ne_cpu_pool.avail_threads_per_core),
GFP_KERNEL);
if (!ne_cpu_pool.avail_threads_per_core) {
rc = -ENOMEM;
goto free_pool_cpumask;
}
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
if (!zalloc_cpumask_var(&ne_cpu_pool.avail_threads_per_core[i], GFP_KERNEL)) {
rc = -ENOMEM;
goto free_cores_cpumask;
}
/*
* Split the NE CPU pool in threads per core to keep the CPU topology
* after offlining the CPUs.
*/
for_each_cpu(cpu, cpu_pool) {
core_id = topology_core_id(cpu);
if (core_id < 0 || core_id >= ne_cpu_pool.nr_parent_vm_cores) {
pr_err("%s: Invalid core id %d for CPU %d\n",
ne_misc_dev.name, core_id, cpu);
rc = -EINVAL;
goto clear_cpumask;
}
cpumask_set_cpu(cpu, ne_cpu_pool.avail_threads_per_core[core_id]);
}
/*
* CPUs that are given to enclave(s) should not be considered online
* by Linux anymore, as the hypervisor will degrade them to floating.
* The physical CPUs (full cores) are carved out of the primary / parent
* VM and given to the enclave VM. The same number of vCPUs would run
* on less pCPUs for the primary / parent VM.
*
* We offline them here, to not degrade performance and expose correct
* topology to Linux and user space.
*/
for_each_cpu(cpu, cpu_pool) {
rc = remove_cpu(cpu);
if (rc != 0) {
pr_err("%s: CPU %d is not offlined [rc=%d]\n",
ne_misc_dev.name, cpu, rc);
goto online_cpus;
}
}
free_cpumask_var(cpu_pool);
ne_cpu_pool.numa_node = numa_node;
mutex_unlock(&ne_cpu_pool.mutex);
return 0;
online_cpus:
for_each_cpu(cpu, cpu_pool)
add_cpu(cpu);
clear_cpumask:
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
cpumask_clear(ne_cpu_pool.avail_threads_per_core[i]);
free_cores_cpumask:
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
free_cpumask_var(ne_cpu_pool.avail_threads_per_core[i]);
kfree(ne_cpu_pool.avail_threads_per_core);
free_pool_cpumask:
free_cpumask_var(cpu_pool);
ne_cpu_pool.nr_parent_vm_cores = 0;
ne_cpu_pool.nr_threads_per_core = 0;
ne_cpu_pool.numa_node = -1;
mutex_unlock(&ne_cpu_pool.mutex);
return rc;
}
/**
* ne_teardown_cpu_pool() - Online the CPUs from the NE CPU pool and cleanup the
* CPU pool.
* @void: No parameters provided.
*
* Context: Process context.
*/
static void ne_teardown_cpu_pool(void)
{
unsigned int cpu = 0;
unsigned int i = 0;
int rc = -EINVAL;
mutex_lock(&ne_cpu_pool.mutex);
if (!ne_cpu_pool.nr_parent_vm_cores) {
mutex_unlock(&ne_cpu_pool.mutex);
return;
}
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++) {
for_each_cpu(cpu, ne_cpu_pool.avail_threads_per_core[i]) {
rc = add_cpu(cpu);
if (rc != 0)
pr_err("%s: CPU %d is not onlined [rc=%d]\n",
ne_misc_dev.name, cpu, rc);
}
cpumask_clear(ne_cpu_pool.avail_threads_per_core[i]);
free_cpumask_var(ne_cpu_pool.avail_threads_per_core[i]);
}
kfree(ne_cpu_pool.avail_threads_per_core);
ne_cpu_pool.nr_parent_vm_cores = 0;
ne_cpu_pool.nr_threads_per_core = 0;
ne_cpu_pool.numa_node = -1;
mutex_unlock(&ne_cpu_pool.mutex);
}
/**
* ne_set_kernel_param() - Set the NE CPU pool value via the NE kernel parameter.
* @val: NE CPU pool string value.
* @kp : NE kernel parameter associated with the NE CPU pool.
*
* Context: Process context.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_set_kernel_param(const char *val, const struct kernel_param *kp)
{
char error_val[] = "";
int rc = -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
if (ne_check_enclaves_created()) {
pr_err("%s: The CPU pool is used by enclave(s)\n", ne_misc_dev.name);
return -EPERM;
}
ne_teardown_cpu_pool();
rc = ne_setup_cpu_pool(val);
if (rc < 0) {
pr_err("%s: Error in setup CPU pool [rc=%d]\n", ne_misc_dev.name, rc);
param_set_copystring(error_val, kp);
return rc;
}
rc = param_set_copystring(val, kp);
if (rc < 0) {
pr_err("%s: Error in param set copystring [rc=%d]\n", ne_misc_dev.name, rc);
ne_teardown_cpu_pool();
param_set_copystring(error_val, kp);
return rc;
}
return 0;
}
/**
* ne_donated_cpu() - Check if the provided CPU is already used by the enclave.
* @ne_enclave : Private data associated with the current enclave.
* @cpu: CPU to check if already used.
*
* Context: Process context. This function is called with the ne_enclave mutex held.
* Return:
* * True if the provided CPU is already used by the enclave.
* * False otherwise.
*/
static bool ne_donated_cpu(struct ne_enclave *ne_enclave, unsigned int cpu)
{
if (cpumask_test_cpu(cpu, ne_enclave->vcpu_ids))
return true;
return false;
}
/**
* ne_get_unused_core_from_cpu_pool() - Get the id of a full core from the
* NE CPU pool.
* @void: No parameters provided.
*
* Context: Process context. This function is called with the ne_enclave and
* ne_cpu_pool mutexes held.
* Return:
* * Core id.
* * -1 if no CPU core available in the pool.
*/
static int ne_get_unused_core_from_cpu_pool(void)
{
int core_id = -1;
unsigned int i = 0;
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
if (!cpumask_empty(ne_cpu_pool.avail_threads_per_core[i])) {
core_id = i;
break;
}
return core_id;
}
/**
* ne_set_enclave_threads_per_core() - Set the threads of the provided core in
* the enclave data structure.
* @ne_enclave : Private data associated with the current enclave.
* @core_id: Core id to get its threads from the NE CPU pool.
* @vcpu_id: vCPU id part of the provided core.
*
* Context: Process context. This function is called with the ne_enclave and
* ne_cpu_pool mutexes held.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_set_enclave_threads_per_core(struct ne_enclave *ne_enclave,
int core_id, u32 vcpu_id)
{
unsigned int cpu = 0;
if (core_id < 0 && vcpu_id == 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"No CPUs available in NE CPU pool\n");
return -NE_ERR_NO_CPUS_AVAIL_IN_POOL;
}
if (core_id < 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"CPU %d is not in NE CPU pool\n", vcpu_id);
return -NE_ERR_VCPU_NOT_IN_CPU_POOL;
}
if (core_id >= ne_enclave->nr_parent_vm_cores) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Invalid core id %d - ne_enclave\n", core_id);
return -NE_ERR_VCPU_INVALID_CPU_CORE;
}
for_each_cpu(cpu, ne_cpu_pool.avail_threads_per_core[core_id])
cpumask_set_cpu(cpu, ne_enclave->threads_per_core[core_id]);
cpumask_clear(ne_cpu_pool.avail_threads_per_core[core_id]);
return 0;
}
/**
* ne_get_cpu_from_cpu_pool() - Get a CPU from the NE CPU pool, either from the
* remaining sibling(s) of a CPU core or the first
* sibling of a new CPU core.
* @ne_enclave : Private data associated with the current enclave.
* @vcpu_id: vCPU to get from the NE CPU pool.
*
* Context: Process context. This function is called with the ne_enclave mutex held.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_get_cpu_from_cpu_pool(struct ne_enclave *ne_enclave, u32 *vcpu_id)
{
int core_id = -1;
unsigned int cpu = 0;
unsigned int i = 0;
int rc = -EINVAL;
/*
* If previously allocated a thread of a core to this enclave, first
* check remaining sibling(s) for new CPU allocations, so that full
* CPU cores are used for the enclave.
*/
for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
for_each_cpu(cpu, ne_enclave->threads_per_core[i])
if (!ne_donated_cpu(ne_enclave, cpu)) {
*vcpu_id = cpu;
return 0;
}
mutex_lock(&ne_cpu_pool.mutex);
/*
* If no remaining siblings, get a core from the NE CPU pool and keep
* track of all the threads in the enclave threads per core data structure.
*/
core_id = ne_get_unused_core_from_cpu_pool();
rc = ne_set_enclave_threads_per_core(ne_enclave, core_id, *vcpu_id);
if (rc < 0)
goto unlock_mutex;
*vcpu_id = cpumask_any(ne_enclave->threads_per_core[core_id]);
rc = 0;
unlock_mutex:
mutex_unlock(&ne_cpu_pool.mutex);
return rc;
}
/**
* ne_get_vcpu_core_from_cpu_pool() - Get from the NE CPU pool the id of the
* core associated with the provided vCPU.
* @vcpu_id: Provided vCPU id to get its associated core id.
*
* Context: Process context. This function is called with the ne_enclave and
* ne_cpu_pool mutexes held.
* Return:
* * Core id.
* * -1 if the provided vCPU is not in the pool.
*/
static int ne_get_vcpu_core_from_cpu_pool(u32 vcpu_id)
{
int core_id = -1;
unsigned int i = 0;
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
if (cpumask_test_cpu(vcpu_id, ne_cpu_pool.avail_threads_per_core[i])) {
core_id = i;
break;
}
return core_id;
}
/**
* ne_check_cpu_in_cpu_pool() - Check if the given vCPU is in the available CPUs
* from the pool.
* @ne_enclave : Private data associated with the current enclave.
* @vcpu_id: ID of the vCPU to check if available in the NE CPU pool.
*
* Context: Process context. This function is called with the ne_enclave mutex held.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_check_cpu_in_cpu_pool(struct ne_enclave *ne_enclave, u32 vcpu_id)
{
int core_id = -1;
unsigned int i = 0;
int rc = -EINVAL;
if (ne_donated_cpu(ne_enclave, vcpu_id)) {
dev_err_ratelimited(ne_misc_dev.this_device,
"CPU %d already used\n", vcpu_id);
return -NE_ERR_VCPU_ALREADY_USED;
}
/*
* If previously allocated a thread of a core to this enclave, but not
* the full core, first check remaining sibling(s).
*/
for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
if (cpumask_test_cpu(vcpu_id, ne_enclave->threads_per_core[i]))
return 0;
mutex_lock(&ne_cpu_pool.mutex);
/*
* If no remaining siblings, get from the NE CPU pool the core
* associated with the vCPU and keep track of all the threads in the
* enclave threads per core data structure.
*/
core_id = ne_get_vcpu_core_from_cpu_pool(vcpu_id);
rc = ne_set_enclave_threads_per_core(ne_enclave, core_id, vcpu_id);
if (rc < 0)
goto unlock_mutex;
rc = 0;
unlock_mutex:
mutex_unlock(&ne_cpu_pool.mutex);
return rc;
}
/**
* ne_add_vcpu_ioctl() - Add a vCPU to the slot associated with the current
* enclave.
* @ne_enclave : Private data associated with the current enclave.
* @vcpu_id: ID of the CPU to be associated with the given slot,
* apic id on x86.
*
* Context: Process context. This function is called with the ne_enclave mutex held.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static int ne_add_vcpu_ioctl(struct ne_enclave *ne_enclave, u32 vcpu_id)
{
struct ne_pci_dev_cmd_reply cmd_reply = {};
struct pci_dev *pdev = ne_devs.ne_pci_dev->pdev;
int rc = -EINVAL;
struct slot_add_vcpu_req slot_add_vcpu_req = {};
if (ne_enclave->mm != current->mm)
return -EIO;
slot_add_vcpu_req.slot_uid = ne_enclave->slot_uid;
slot_add_vcpu_req.vcpu_id = vcpu_id;
rc = ne_do_request(pdev, SLOT_ADD_VCPU,
&slot_add_vcpu_req, sizeof(slot_add_vcpu_req),
&cmd_reply, sizeof(cmd_reply));
if (rc < 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in slot add vCPU [rc=%d]\n", rc);
return rc;
}
cpumask_set_cpu(vcpu_id, ne_enclave->vcpu_ids);
ne_enclave->nr_vcpus++;
return 0;
}
/**
* ne_enclave_ioctl() - Ioctl function provided by the enclave file.
* @file: File associated with this ioctl function.
* @cmd: The command that is set for the ioctl call.
* @arg: The argument that is provided for the ioctl call.
*
* Context: Process context.
* Return:
* * 0 on success.
* * Negative return value on failure.
*/
static long ne_enclave_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct ne_enclave *ne_enclave = file->private_data;
switch (cmd) {
case NE_ADD_VCPU: {
int rc = -EINVAL;
u32 vcpu_id = 0;
if (copy_from_user(&vcpu_id, (void __user *)arg, sizeof(vcpu_id)))
return -EFAULT;
mutex_lock(&ne_enclave->enclave_info_mutex);
if (ne_enclave->state != NE_STATE_INIT) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Enclave is not in init state\n");
mutex_unlock(&ne_enclave->enclave_info_mutex);
return -NE_ERR_NOT_IN_INIT_STATE;
}
if (vcpu_id >= (ne_enclave->nr_parent_vm_cores *
ne_enclave->nr_threads_per_core)) {
dev_err_ratelimited(ne_misc_dev.this_device,
"vCPU id higher than max CPU id\n");
mutex_unlock(&ne_enclave->enclave_info_mutex);
return -NE_ERR_INVALID_VCPU;
}
if (!vcpu_id) {
/* Use the CPU pool for choosing a CPU for the enclave. */
rc = ne_get_cpu_from_cpu_pool(ne_enclave, &vcpu_id);
if (rc < 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in get CPU from pool [rc=%d]\n",
rc);
mutex_unlock(&ne_enclave->enclave_info_mutex);
return rc;
}
} else {
/* Check if the provided vCPU is available in the NE CPU pool. */
rc = ne_check_cpu_in_cpu_pool(ne_enclave, vcpu_id);
if (rc < 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in check CPU %d in pool [rc=%d]\n",
vcpu_id, rc);
mutex_unlock(&ne_enclave->enclave_info_mutex);
return rc;
}
}
rc = ne_add_vcpu_ioctl(ne_enclave, vcpu_id);
if (rc < 0) {
mutex_unlock(&ne_enclave->enclave_info_mutex);
return rc;
}
mutex_unlock(&ne_enclave->enclave_info_mutex);
if (copy_to_user((void __user *)arg, &vcpu_id, sizeof(vcpu_id)))
return -EFAULT;
return 0;
}
default:
return -ENOTTY;
}
return 0;
}
/**
* ne_enclave_poll() - Poll functionality used for enclave out-of-band events.
* @file: File associated with this poll function.
* @wait: Poll table data structure.
*
* Context: Process context.
* Return:
* * Poll mask.
*/
static __poll_t ne_enclave_poll(struct file *file, poll_table *wait)
{
__poll_t mask = 0;
struct ne_enclave *ne_enclave = file->private_data;
poll_wait(file, &ne_enclave->eventq, wait);
if (!ne_enclave->has_event)
return mask;
mask = POLLHUP;
return mask;
}
static const struct file_operations ne_enclave_fops = {
.owner = THIS_MODULE,
.llseek = noop_llseek,
.poll = ne_enclave_poll,
.unlocked_ioctl = ne_enclave_ioctl,
};
/**
* ne_create_vm_ioctl() - Alloc slot to be associated with an enclave. Create
* enclave file descriptor to be further used for enclave
* resources handling e.g. memory regions and CPUs.
* @ne_pci_dev : Private data associated with the PCI device.
* @slot_uid: Generated unique slot id associated with an enclave.
*
* Context: Process context. This function is called with the ne_pci_dev enclave
* mutex held.
* Return:
* * Enclave fd on success.
* * Negative return value on failure.
*/
static int ne_create_vm_ioctl(struct ne_pci_dev *ne_pci_dev, u64 *slot_uid)
{
struct ne_pci_dev_cmd_reply cmd_reply = {};
int enclave_fd = -1;
struct file *enclave_file = NULL;
unsigned int i = 0;
struct ne_enclave *ne_enclave = NULL;
struct pci_dev *pdev = ne_pci_dev->pdev;
int rc = -EINVAL;
struct slot_alloc_req slot_alloc_req = {};
mutex_lock(&ne_cpu_pool.mutex);
for (i = 0; i < ne_cpu_pool.nr_parent_vm_cores; i++)
if (!cpumask_empty(ne_cpu_pool.avail_threads_per_core[i]))
break;
if (i == ne_cpu_pool.nr_parent_vm_cores) {
dev_err_ratelimited(ne_misc_dev.this_device,
"No CPUs available in CPU pool\n");
mutex_unlock(&ne_cpu_pool.mutex);
return -NE_ERR_NO_CPUS_AVAIL_IN_POOL;
}
mutex_unlock(&ne_cpu_pool.mutex);
ne_enclave = kzalloc(sizeof(*ne_enclave), GFP_KERNEL);
if (!ne_enclave)
return -ENOMEM;
mutex_lock(&ne_cpu_pool.mutex);
ne_enclave->nr_parent_vm_cores = ne_cpu_pool.nr_parent_vm_cores;
ne_enclave->nr_threads_per_core = ne_cpu_pool.nr_threads_per_core;
ne_enclave->numa_node = ne_cpu_pool.numa_node;
mutex_unlock(&ne_cpu_pool.mutex);
ne_enclave->threads_per_core = kcalloc(ne_enclave->nr_parent_vm_cores,
sizeof(*ne_enclave->threads_per_core), GFP_KERNEL);
if (!ne_enclave->threads_per_core) {
rc = -ENOMEM;
goto free_ne_enclave;
}
for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
if (!zalloc_cpumask_var(&ne_enclave->threads_per_core[i], GFP_KERNEL)) {
rc = -ENOMEM;
goto free_cpumask;
}
if (!zalloc_cpumask_var(&ne_enclave->vcpu_ids, GFP_KERNEL)) {
rc = -ENOMEM;
goto free_cpumask;
}
enclave_fd = get_unused_fd_flags(O_CLOEXEC);
if (enclave_fd < 0) {
rc = enclave_fd;
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in getting unused fd [rc=%d]\n", rc);
goto free_cpumask;
}
enclave_file = anon_inode_getfile("ne-vm", &ne_enclave_fops, ne_enclave, O_RDWR);
if (IS_ERR(enclave_file)) {
rc = PTR_ERR(enclave_file);
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in anon inode get file [rc=%d]\n", rc);
goto put_fd;
}
rc = ne_do_request(pdev, SLOT_ALLOC,
&slot_alloc_req, sizeof(slot_alloc_req),
&cmd_reply, sizeof(cmd_reply));
if (rc < 0) {
dev_err_ratelimited(ne_misc_dev.this_device,
"Error in slot alloc [rc=%d]\n", rc);
goto put_file;
}
init_waitqueue_head(&ne_enclave->eventq);
ne_enclave->has_event = false;
mutex_init(&ne_enclave->enclave_info_mutex);
ne_enclave->max_mem_regions = cmd_reply.mem_regions;
INIT_LIST_HEAD(&ne_enclave->mem_regions_list);
ne_enclave->mm = current->mm;
ne_enclave->slot_uid = cmd_reply.slot_uid;
ne_enclave->state = NE_STATE_INIT;
list_add(&ne_enclave->enclave_list_entry, &ne_pci_dev->enclaves_list);
*slot_uid = ne_enclave->slot_uid;
fd_install(enclave_fd, enclave_file);
return enclave_fd;
put_file:
fput(enclave_file);
put_fd:
put_unused_fd(enclave_fd);
free_cpumask:
free_cpumask_var(ne_enclave->vcpu_ids);
for (i = 0; i < ne_enclave->nr_parent_vm_cores; i++)
free_cpumask_var(ne_enclave->threads_per_core[i]);
kfree(ne_enclave->threads_per_core);
free_ne_enclave:
kfree(ne_enclave);
return rc;
}
/**
* ne_ioctl() - Ioctl function provided by the NE misc device.
* @file: File associated with this ioctl function.
* @cmd: The command that is set for the ioctl call.
* @arg: The argument that is provided for the ioctl call.
*
* Context: Process context.
* Return:
* * Ioctl result (e.g. enclave file descriptor) on success.
* * Negative return value on failure.
*/
static long ne_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
case NE_CREATE_VM: {
int enclave_fd = -1;
struct file *enclave_file = NULL;
struct ne_pci_dev *ne_pci_dev = ne_devs.ne_pci_dev;
int rc = -EINVAL;
u64 slot_uid = 0;
mutex_lock(&ne_pci_dev->enclaves_list_mutex);
enclave_fd = ne_create_vm_ioctl(ne_pci_dev, &slot_uid);
if (enclave_fd < 0) {
rc = enclave_fd;
mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
return rc;
}
mutex_unlock(&ne_pci_dev->enclaves_list_mutex);
if (copy_to_user((void __user *)arg, &slot_uid, sizeof(slot_uid))) {
enclave_file = fget(enclave_fd);
/* Decrement file refs to have release() called. */
fput(enclave_file);
fput(enclave_file);
put_unused_fd(enclave_fd);
return -EFAULT;
}
return enclave_fd;
}
default:
return -ENOTTY;
}
return 0;
}
static int __init ne_init(void)
{
mutex_init(&ne_cpu_pool.mutex);
return pci_register_driver(&ne_pci_driver);
}
static void __exit ne_exit(void)
{
pci_unregister_driver(&ne_pci_driver);
ne_teardown_cpu_pool();
}
module_init(ne_init);
module_exit(ne_exit);
MODULE_AUTHOR("Amazon.com, Inc. or its affiliates");
MODULE_DESCRIPTION("Nitro Enclaves Driver");
MODULE_LICENSE("GPL v2");
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