+ bool ret = false;
+
+ if (!pdev)
+ return ret;
+
+ ne_pci_dev = pci_get_drvdata(pdev);
+ if (!ne_pci_dev) {
+ pci_dev_put(pdev);
+
+ 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);
+
+ pci_dev_put(pdev);
+
+ 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 = NULL;
+ unsigned int cpu_sibling = 0;
+ unsigned int i = 0;
+ int numa_node = -1;
+ int rc = -EINVAL;
+
+ if (!ne_cpu_list)
+ return 0;
+
+ 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 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 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;
+ }
+ }
+ }
+
+ ne_cpu_pool.avail_cores_size = nr_cpu_ids / smp_num_siblings;
+
+ ne_cpu_pool.avail_cores = kcalloc(ne_cpu_pool.avail_cores_size,
+ sizeof(*ne_cpu_pool.avail_cores),
+ GFP_KERNEL);
+ if (!ne_cpu_pool.avail_cores) {
+ rc = -ENOMEM;
+
+ goto free_pool_cpumask;
+ }
+
+ for (i = 0; i < ne_cpu_pool.avail_cores_size; i++)
+ if (!zalloc_cpumask_var(&ne_cpu_pool.avail_cores[i],
GFP_KERNEL)) {
+ rc = -ENOMEM;
+
+ goto free_cores_cpumask;
+ }
+
+ /* Split the NE CPU pool in CPU cores. */
+ for_each_cpu(cpu, cpu_pool) {
+ core_id = topology_core_id(cpu);
+ if (core_id < 0 || core_id >= ne_cpu_pool.avail_cores_size) {
+ pr_err("%s: Invalid core id %d\n",
+ ne_misc_dev.name, core_id);
+
+ rc = -EINVAL;
+
+ goto clear_cpumask;
+ }
+
+ cpumask_set_cpu(cpu, ne_cpu_pool.avail_cores[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.avail_cores_size; i++)
+ cpumask_clear(ne_cpu_pool.avail_cores[i]);
+free_cores_cpumask:
+ for (i = 0; i < ne_cpu_pool.avail_cores_size; i++)
+ free_cpumask_var(ne_cpu_pool.avail_cores[i]);
+ kfree(ne_cpu_pool.avail_cores);
+ ne_cpu_pool.avail_cores_size = 0;
+free_pool_cpumask:
+ free_cpumask_var(cpu_pool);
+ 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.avail_cores_size) {
+ mutex_unlock(&ne_cpu_pool.mutex);
+
+ return;
+ }
+
+ for (i = 0; i < ne_cpu_pool.avail_cores_size; i++) {
+ for_each_cpu(cpu, ne_cpu_pool.avail_cores[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_cores[i]);
+
+ free_cpumask_var(ne_cpu_pool.avail_cores[i]);
+ }
+
+ kfree(ne_cpu_pool.avail_cores);
+ ne_cpu_pool.avail_cores_size = 0;
+
+ 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;
+ }
+
+ return param_set_copystring(val, kp);
+}
+
+/**
+ * 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.
+ *
+ * Context: Process context. This function is called with the
ne_enclave mutex held.
+ * Return:
+ * * vCPU id.
+ * * 0, if no CPU available in the pool.
+ */
+static unsigned int ne_get_cpu_from_cpu_pool(struct ne_enclave
*ne_enclave)
+{
+ int core_id = -1;
+ unsigned int cpu = 0;
+ unsigned int i = 0;
+ unsigned int vcpu_id = 0;
+
+ /* There are CPU siblings available to choose from. */
+ for (i = 0; i < ne_enclave->avail_cpu_cores_size; i++)
+ for_each_cpu(cpu, ne_enclave->avail_cpu_cores[i])
