From bd47c995c0e4e7b5ea2b7074a92ca3ff95e25cd0 Mon Sep 17 00:00:00 2001 From: Andra Paraschiv Date: Mon, 21 Sep 2020 15:17:21 +0300 Subject: [PATCH] nitro_enclaves: Init misc device providing the ioctl interface The Nitro Enclaves driver provides an ioctl interface to the user space for enclave lifetime management e.g. enclave creation / termination and setting enclave resources such as memory and CPU. This ioctl interface is mapped to a Nitro Enclaves misc device. Changelog v9 -> v10 * Update commit message to include the changelog before the SoB tag(s). v8 -> v9 * Use the ne_devs data structure to get the refs for the NE misc device in the NE PCI device driver logic. v7 -> v8 * Add define for the CID of the primary / parent VM. * Update the NE PCI driver shutdown logic to include misc device deregister. v6 -> v7 * Set the NE PCI device the parent of the NE misc device to be able to use it in the ioctl logic. * Update the naming and add more comments to make more clear the logic of handling full CPU cores and dedicating them to the enclave. v5 -> v6 * Remove the ioctl to query API version. * Update documentation to kernel-doc format. v4 -> v5 * Update the size of the NE CPU pool string from 4096 to 512 chars. v3 -> v4 * Use dev_err instead of custom NE log pattern. * Remove the NE CPU pool init during kernel module loading, as the CPU pool is now setup at runtime, via a sysfs file for the kernel parameter. * Add minimum enclave memory size definition. v2 -> v3 * Remove the GPL additional wording as SPDX-License-Identifier is already in place. * Remove the WARN_ON calls. * Remove linux/bug and linux/kvm_host includes that are not needed. * Remove "ratelimited" from the logs that are not in the ioctl call paths. * Remove file ops that do nothing for now - open and release. v1 -> v2 * Add log pattern for NE. * Update goto labels to match their purpose. * Update ne_cpu_pool data structure to include the global mutex. * Update NE misc device mode to 0660. * Check if the CPU siblings are included in the NE CPU pool, as full CPU cores are given for the enclave(s). Reviewed-by: Alexander Graf Signed-off-by: Andra Paraschiv Link: https://lore.kernel.org/r/20200921121732.44291-8-andraprs@amazon.com Signed-off-by: Greg Kroah-Hartman --- drivers/virt/nitro_enclaves/ne_misc_dev.c | 139 ++++++++++++++++++++++ drivers/virt/nitro_enclaves/ne_pci_dev.c | 14 +++ 2 files changed, 153 insertions(+) create mode 100644 drivers/virt/nitro_enclaves/ne_misc_dev.c diff --git a/drivers/virt/nitro_enclaves/ne_misc_dev.c b/drivers/virt/nitro_enclaves/ne_misc_dev.c new file mode 100644 index 000000000000..c06825070313 --- /dev/null +++ b/drivers/virt/nitro_enclaves/ne_misc_dev.c @@ -0,0 +1,139 @@ +// 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 const struct file_operations ne_fops = { + .owner = THIS_MODULE, + .llseek = noop_llseek, +}; + +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 const struct kernel_param_ops ne_cpu_pool_ops = { + .get = param_get_string, +}; + +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 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; + +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); +} + +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"); diff --git a/drivers/virt/nitro_enclaves/ne_pci_dev.c b/drivers/virt/nitro_enclaves/ne_pci_dev.c index 6654cc8a1bc3..b9c1de41e300 100644 --- a/drivers/virt/nitro_enclaves/ne_pci_dev.c +++ b/drivers/virt/nitro_enclaves/ne_pci_dev.c @@ -523,8 +523,18 @@ static int ne_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) ne_devs.ne_pci_dev = ne_pci_dev; + rc = misc_register(ne_devs.ne_misc_dev); + if (rc < 0) { + dev_err(&pdev->dev, "Error in misc dev register [rc=%d]\n", rc); + + goto disable_ne_pci_dev; + } + return 0; +disable_ne_pci_dev: + ne_devs.ne_pci_dev = NULL; + ne_pci_dev_disable(pdev); teardown_msix: ne_teardown_msix(pdev); iounmap_pci_bar: @@ -550,6 +560,8 @@ static void ne_pci_remove(struct pci_dev *pdev) { struct ne_pci_dev *ne_pci_dev = pci_get_drvdata(pdev); + misc_deregister(ne_devs.ne_misc_dev); + ne_devs.ne_pci_dev = NULL; ne_pci_dev_disable(pdev); @@ -580,6 +592,8 @@ static void ne_pci_shutdown(struct pci_dev *pdev) if (!ne_pci_dev) return; + misc_deregister(ne_devs.ne_misc_dev); + ne_devs.ne_pci_dev = NULL; ne_pci_dev_disable(pdev);