963 lines
24 KiB
C
963 lines
24 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright(c) 2016-20 Intel Corporation. */
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#include <linux/file.h>
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#include <linux/freezer.h>
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#include <linux/highmem.h>
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#include <linux/kthread.h>
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#include <linux/miscdevice.h>
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#include <linux/node.h>
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#include <linux/pagemap.h>
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#include <linux/ratelimit.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/signal.h>
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#include <linux/slab.h>
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#include <linux/sysfs.h>
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#include <asm/sgx.h>
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#include "driver.h"
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#include "encl.h"
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#include "encls.h"
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struct sgx_epc_section sgx_epc_sections[SGX_MAX_EPC_SECTIONS];
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static int sgx_nr_epc_sections;
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static struct task_struct *ksgxd_tsk;
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static DECLARE_WAIT_QUEUE_HEAD(ksgxd_waitq);
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static DEFINE_XARRAY(sgx_epc_address_space);
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/*
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* These variables are part of the state of the reclaimer, and must be accessed
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* with sgx_reclaimer_lock acquired.
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*/
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static LIST_HEAD(sgx_active_page_list);
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static DEFINE_SPINLOCK(sgx_reclaimer_lock);
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static atomic_long_t sgx_nr_free_pages = ATOMIC_LONG_INIT(0);
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/* Nodes with one or more EPC sections. */
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static nodemask_t sgx_numa_mask;
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/*
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* Array with one list_head for each possible NUMA node. Each
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* list contains all the sgx_epc_section's which are on that
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* node.
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*/
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static struct sgx_numa_node *sgx_numa_nodes;
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static LIST_HEAD(sgx_dirty_page_list);
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/*
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* Reset post-kexec EPC pages to the uninitialized state. The pages are removed
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* from the input list, and made available for the page allocator. SECS pages
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* prepending their children in the input list are left intact.
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*
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* Return 0 when sanitization was successful or kthread was stopped, and the
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* number of unsanitized pages otherwise.
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*/
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static unsigned long __sgx_sanitize_pages(struct list_head *dirty_page_list)
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{
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unsigned long left_dirty = 0;
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struct sgx_epc_page *page;
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LIST_HEAD(dirty);
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int ret;
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/* dirty_page_list is thread-local, no need for a lock: */
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while (!list_empty(dirty_page_list)) {
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if (kthread_should_stop())
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return 0;
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page = list_first_entry(dirty_page_list, struct sgx_epc_page, list);
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/*
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* Checking page->poison without holding the node->lock
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* is racy, but losing the race (i.e. poison is set just
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* after the check) just means __eremove() will be uselessly
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* called for a page that sgx_free_epc_page() will put onto
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* the node->sgx_poison_page_list later.
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*/
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if (page->poison) {
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struct sgx_epc_section *section = &sgx_epc_sections[page->section];
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struct sgx_numa_node *node = section->node;
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spin_lock(&node->lock);
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list_move(&page->list, &node->sgx_poison_page_list);
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spin_unlock(&node->lock);
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continue;
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}
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ret = __eremove(sgx_get_epc_virt_addr(page));
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if (!ret) {
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/*
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* page is now sanitized. Make it available via the SGX
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* page allocator:
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*/
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list_del(&page->list);
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sgx_free_epc_page(page);
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} else {
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/* The page is not yet clean - move to the dirty list. */
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list_move_tail(&page->list, &dirty);
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left_dirty++;
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}
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cond_resched();
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}
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list_splice(&dirty, dirty_page_list);
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return left_dirty;
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}
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static bool sgx_reclaimer_age(struct sgx_epc_page *epc_page)
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{
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struct sgx_encl_page *page = epc_page->owner;
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struct sgx_encl *encl = page->encl;
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struct sgx_encl_mm *encl_mm;
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bool ret = true;
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int idx;
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idx = srcu_read_lock(&encl->srcu);
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list_for_each_entry_rcu(encl_mm, &encl->mm_list, list) {
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if (!mmget_not_zero(encl_mm->mm))
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continue;
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mmap_read_lock(encl_mm->mm);
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ret = !sgx_encl_test_and_clear_young(encl_mm->mm, page);
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mmap_read_unlock(encl_mm->mm);
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mmput_async(encl_mm->mm);
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if (!ret)
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break;
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}
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srcu_read_unlock(&encl->srcu, idx);
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if (!ret)
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return false;
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return true;
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}
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static void sgx_reclaimer_block(struct sgx_epc_page *epc_page)
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{
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struct sgx_encl_page *page = epc_page->owner;
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unsigned long addr = page->desc & PAGE_MASK;
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struct sgx_encl *encl = page->encl;
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int ret;
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sgx_zap_enclave_ptes(encl, addr);
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mutex_lock(&encl->lock);
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ret = __eblock(sgx_get_epc_virt_addr(epc_page));
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if (encls_failed(ret))
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ENCLS_WARN(ret, "EBLOCK");
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mutex_unlock(&encl->lock);
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}
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static int __sgx_encl_ewb(struct sgx_epc_page *epc_page, void *va_slot,
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struct sgx_backing *backing)
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{
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struct sgx_pageinfo pginfo;
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int ret;
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pginfo.addr = 0;
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pginfo.secs = 0;
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pginfo.contents = (unsigned long)kmap_local_page(backing->contents);
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pginfo.metadata = (unsigned long)kmap_local_page(backing->pcmd) +
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backing->pcmd_offset;
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ret = __ewb(&pginfo, sgx_get_epc_virt_addr(epc_page), va_slot);
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set_page_dirty(backing->pcmd);
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set_page_dirty(backing->contents);
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kunmap_local((void *)(unsigned long)(pginfo.metadata -
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backing->pcmd_offset));
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kunmap_local((void *)(unsigned long)pginfo.contents);
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return ret;
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}
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void sgx_ipi_cb(void *info)
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{
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}
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/*
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* Swap page to the regular memory transformed to the blocked state by using
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* EBLOCK, which means that it can no longer be referenced (no new TLB entries).
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*
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* The first trial just tries to write the page assuming that some other thread
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* has reset the count for threads inside the enclave by using ETRACK, and
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* previous thread count has been zeroed out. The second trial calls ETRACK
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* before EWB. If that fails we kick all the HW threads out, and then do EWB,
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* which should be guaranteed the succeed.
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*/
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static void sgx_encl_ewb(struct sgx_epc_page *epc_page,
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struct sgx_backing *backing)
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{
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struct sgx_encl_page *encl_page = epc_page->owner;
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struct sgx_encl *encl = encl_page->encl;
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struct sgx_va_page *va_page;
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unsigned int va_offset;
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void *va_slot;
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int ret;
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encl_page->desc &= ~SGX_ENCL_PAGE_BEING_RECLAIMED;
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va_page = list_first_entry(&encl->va_pages, struct sgx_va_page,
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list);
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va_offset = sgx_alloc_va_slot(va_page);
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va_slot = sgx_get_epc_virt_addr(va_page->epc_page) + va_offset;
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if (sgx_va_page_full(va_page))
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list_move_tail(&va_page->list, &encl->va_pages);
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ret = __sgx_encl_ewb(epc_page, va_slot, backing);
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if (ret == SGX_NOT_TRACKED) {
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ret = __etrack(sgx_get_epc_virt_addr(encl->secs.epc_page));
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if (ret) {
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if (encls_failed(ret))
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ENCLS_WARN(ret, "ETRACK");
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}
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ret = __sgx_encl_ewb(epc_page, va_slot, backing);
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if (ret == SGX_NOT_TRACKED) {
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/*
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* Slow path, send IPIs to kick cpus out of the
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* enclave. Note, it's imperative that the cpu
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* mask is generated *after* ETRACK, else we'll
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* miss cpus that entered the enclave between
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* generating the mask and incrementing epoch.
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*/
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on_each_cpu_mask(sgx_encl_cpumask(encl),
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sgx_ipi_cb, NULL, 1);
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ret = __sgx_encl_ewb(epc_page, va_slot, backing);
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}
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}
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if (ret) {
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if (encls_failed(ret))
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ENCLS_WARN(ret, "EWB");
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sgx_free_va_slot(va_page, va_offset);
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} else {
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encl_page->desc |= va_offset;
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encl_page->va_page = va_page;
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}
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}
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static void sgx_reclaimer_write(struct sgx_epc_page *epc_page,
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struct sgx_backing *backing)
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{
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struct sgx_encl_page *encl_page = epc_page->owner;
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struct sgx_encl *encl = encl_page->encl;
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struct sgx_backing secs_backing;
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int ret;
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mutex_lock(&encl->lock);
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sgx_encl_ewb(epc_page, backing);
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encl_page->epc_page = NULL;
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encl->secs_child_cnt--;
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sgx_encl_put_backing(backing);
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if (!encl->secs_child_cnt && test_bit(SGX_ENCL_INITIALIZED, &encl->flags)) {
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ret = sgx_encl_alloc_backing(encl, PFN_DOWN(encl->size),
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&secs_backing);
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if (ret)
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goto out;
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sgx_encl_ewb(encl->secs.epc_page, &secs_backing);
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sgx_encl_free_epc_page(encl->secs.epc_page);
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encl->secs.epc_page = NULL;
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sgx_encl_put_backing(&secs_backing);
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}
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out:
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mutex_unlock(&encl->lock);
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}
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/*
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* Take a fixed number of pages from the head of the active page pool and
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* reclaim them to the enclave's private shmem files. Skip the pages, which have
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* been accessed since the last scan. Move those pages to the tail of active
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* page pool so that the pages get scanned in LRU like fashion.
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*
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* Batch process a chunk of pages (at the moment 16) in order to degrade amount
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* of IPI's and ETRACK's potentially required. sgx_encl_ewb() does degrade a bit
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* among the HW threads with three stage EWB pipeline (EWB, ETRACK + EWB and IPI
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* + EWB) but not sufficiently. Reclaiming one page at a time would also be
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* problematic as it would increase the lock contention too much, which would
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* halt forward progress.
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*/
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static void sgx_reclaim_pages(void)
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{
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struct sgx_epc_page *chunk[SGX_NR_TO_SCAN];
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struct sgx_backing backing[SGX_NR_TO_SCAN];
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struct sgx_encl_page *encl_page;
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struct sgx_epc_page *epc_page;
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pgoff_t page_index;
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int cnt = 0;
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int ret;
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int i;
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spin_lock(&sgx_reclaimer_lock);
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for (i = 0; i < SGX_NR_TO_SCAN; i++) {
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if (list_empty(&sgx_active_page_list))
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break;
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epc_page = list_first_entry(&sgx_active_page_list,
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struct sgx_epc_page, list);
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list_del_init(&epc_page->list);
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encl_page = epc_page->owner;
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if (kref_get_unless_zero(&encl_page->encl->refcount) != 0)
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chunk[cnt++] = epc_page;
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else
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/* The owner is freeing the page. No need to add the
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* page back to the list of reclaimable pages.
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*/
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epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
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}
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spin_unlock(&sgx_reclaimer_lock);
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for (i = 0; i < cnt; i++) {
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epc_page = chunk[i];
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encl_page = epc_page->owner;
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if (!sgx_reclaimer_age(epc_page))
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goto skip;
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page_index = PFN_DOWN(encl_page->desc - encl_page->encl->base);
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mutex_lock(&encl_page->encl->lock);
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ret = sgx_encl_alloc_backing(encl_page->encl, page_index, &backing[i]);
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if (ret) {
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mutex_unlock(&encl_page->encl->lock);
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goto skip;
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}
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encl_page->desc |= SGX_ENCL_PAGE_BEING_RECLAIMED;
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mutex_unlock(&encl_page->encl->lock);
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continue;
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skip:
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spin_lock(&sgx_reclaimer_lock);
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list_add_tail(&epc_page->list, &sgx_active_page_list);
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spin_unlock(&sgx_reclaimer_lock);
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kref_put(&encl_page->encl->refcount, sgx_encl_release);
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chunk[i] = NULL;
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}
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for (i = 0; i < cnt; i++) {
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epc_page = chunk[i];
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if (epc_page)
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sgx_reclaimer_block(epc_page);
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}
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for (i = 0; i < cnt; i++) {
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epc_page = chunk[i];
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if (!epc_page)
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continue;
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encl_page = epc_page->owner;
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sgx_reclaimer_write(epc_page, &backing[i]);
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kref_put(&encl_page->encl->refcount, sgx_encl_release);
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epc_page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
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sgx_free_epc_page(epc_page);
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}
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}
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static bool sgx_should_reclaim(unsigned long watermark)
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{
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return atomic_long_read(&sgx_nr_free_pages) < watermark &&
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!list_empty(&sgx_active_page_list);
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}
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/*
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* sgx_reclaim_direct() should be called (without enclave's mutex held)
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* in locations where SGX memory resources might be low and might be
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* needed in order to make forward progress.
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*/
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void sgx_reclaim_direct(void)
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{
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if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
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sgx_reclaim_pages();
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}
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static int ksgxd(void *p)
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{
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set_freezable();
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/*
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* Sanitize pages in order to recover from kexec(). The 2nd pass is
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* required for SECS pages, whose child pages blocked EREMOVE.
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*/
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__sgx_sanitize_pages(&sgx_dirty_page_list);
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WARN_ON(__sgx_sanitize_pages(&sgx_dirty_page_list));
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while (!kthread_should_stop()) {
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if (try_to_freeze())
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continue;
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wait_event_freezable(ksgxd_waitq,
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kthread_should_stop() ||
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sgx_should_reclaim(SGX_NR_HIGH_PAGES));
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if (sgx_should_reclaim(SGX_NR_HIGH_PAGES))
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sgx_reclaim_pages();
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cond_resched();
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}
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return 0;
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}
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static bool __init sgx_page_reclaimer_init(void)
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{
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struct task_struct *tsk;
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tsk = kthread_run(ksgxd, NULL, "ksgxd");
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if (IS_ERR(tsk))
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return false;
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ksgxd_tsk = tsk;
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return true;
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}
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bool current_is_ksgxd(void)
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{
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return current == ksgxd_tsk;
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}
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static struct sgx_epc_page *__sgx_alloc_epc_page_from_node(int nid)
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{
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struct sgx_numa_node *node = &sgx_numa_nodes[nid];
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struct sgx_epc_page *page = NULL;
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spin_lock(&node->lock);
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if (list_empty(&node->free_page_list)) {
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spin_unlock(&node->lock);
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return NULL;
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}
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page = list_first_entry(&node->free_page_list, struct sgx_epc_page, list);
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list_del_init(&page->list);
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page->flags = 0;
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spin_unlock(&node->lock);
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atomic_long_dec(&sgx_nr_free_pages);
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return page;
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}
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/**
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* __sgx_alloc_epc_page() - Allocate an EPC page
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*
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* Iterate through NUMA nodes and reserve ia free EPC page to the caller. Start
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* from the NUMA node, where the caller is executing.
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*
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* Return:
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* - an EPC page: A borrowed EPC pages were available.
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* - NULL: Out of EPC pages.
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*/
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struct sgx_epc_page *__sgx_alloc_epc_page(void)
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{
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struct sgx_epc_page *page;
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int nid_of_current = numa_node_id();
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int nid = nid_of_current;
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if (node_isset(nid_of_current, sgx_numa_mask)) {
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page = __sgx_alloc_epc_page_from_node(nid_of_current);
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if (page)
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return page;
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}
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/* Fall back to the non-local NUMA nodes: */
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while (true) {
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nid = next_node_in(nid, sgx_numa_mask);
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if (nid == nid_of_current)
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break;
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page = __sgx_alloc_epc_page_from_node(nid);
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if (page)
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return page;
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}
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return ERR_PTR(-ENOMEM);
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}
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|
|
/**
|
|
* sgx_mark_page_reclaimable() - Mark a page as reclaimable
|
|
* @page: EPC page
|
|
*
|
|
* Mark a page as reclaimable and add it to the active page list. Pages
|
|
* are automatically removed from the active list when freed.
|
|
*/
|
|
void sgx_mark_page_reclaimable(struct sgx_epc_page *page)
|
|
{
|
|
spin_lock(&sgx_reclaimer_lock);
|
|
page->flags |= SGX_EPC_PAGE_RECLAIMER_TRACKED;
|
|
list_add_tail(&page->list, &sgx_active_page_list);
|
|
spin_unlock(&sgx_reclaimer_lock);
|
|
}
|
|
|
|
/**
|
|
* sgx_unmark_page_reclaimable() - Remove a page from the reclaim list
|
|
* @page: EPC page
|
|
*
|
|
* Clear the reclaimable flag and remove the page from the active page list.
|
|
*
|
|
* Return:
|
|
* 0 on success,
|
|
* -EBUSY if the page is in the process of being reclaimed
|
|
*/
|
|
int sgx_unmark_page_reclaimable(struct sgx_epc_page *page)
|
|
{
|
|
spin_lock(&sgx_reclaimer_lock);
|
|
if (page->flags & SGX_EPC_PAGE_RECLAIMER_TRACKED) {
|
|
/* The page is being reclaimed. */
|
|
if (list_empty(&page->list)) {
|
|
spin_unlock(&sgx_reclaimer_lock);
|
|
return -EBUSY;
|
|
}
|
|
|
|
list_del(&page->list);
|
|
page->flags &= ~SGX_EPC_PAGE_RECLAIMER_TRACKED;
|
|
}
|
|
spin_unlock(&sgx_reclaimer_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* sgx_alloc_epc_page() - Allocate an EPC page
|
|
* @owner: the owner of the EPC page
|
|
* @reclaim: reclaim pages if necessary
|
|
*
|
|
* Iterate through EPC sections and borrow a free EPC page to the caller. When a
|
|
* page is no longer needed it must be released with sgx_free_epc_page(). If
|
|
* @reclaim is set to true, directly reclaim pages when we are out of pages. No
|
|
* mm's can be locked when @reclaim is set to true.
|
|
*
|
|
* Finally, wake up ksgxd when the number of pages goes below the watermark
|
|
* before returning back to the caller.
|
|
*
|
|
* Return:
|
|
* an EPC page,
|
|
* -errno on error
|
|
*/
|
|
struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
|
|
{
|
|
struct sgx_epc_page *page;
|
|
|
|
for ( ; ; ) {
|
|
page = __sgx_alloc_epc_page();
|
|
if (!IS_ERR(page)) {
|
|
page->owner = owner;
|
|
break;
|
|
}
|
|
|
|
if (list_empty(&sgx_active_page_list))
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
if (!reclaim) {
|
|
page = ERR_PTR(-EBUSY);
|
|
break;
|
|
}
|
|
|
|
if (signal_pending(current)) {
|
|
page = ERR_PTR(-ERESTARTSYS);
|
|
break;
|
|
}
|
|
|
|
sgx_reclaim_pages();
|
|
cond_resched();
|
|
}
|
|
|
|
if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
|
|
wake_up(&ksgxd_waitq);
|
|
|
|
return page;
|
|
}
|
|
|
|
/**
|
|
* sgx_free_epc_page() - Free an EPC page
|
|
* @page: an EPC page
|
|
*
|
|
* Put the EPC page back to the list of free pages. It's the caller's
|
|
* responsibility to make sure that the page is in uninitialized state. In other
|
|
* words, do EREMOVE, EWB or whatever operation is necessary before calling
|
|
* this function.
|
|
*/
|
|
void sgx_free_epc_page(struct sgx_epc_page *page)
|
|
{
|
|
struct sgx_epc_section *section = &sgx_epc_sections[page->section];
|
|
struct sgx_numa_node *node = section->node;
|
|
|
|
spin_lock(&node->lock);
|
|
|
|
page->owner = NULL;
|
|
if (page->poison)
|
|
list_add(&page->list, &node->sgx_poison_page_list);
|
|
else
|
|
list_add_tail(&page->list, &node->free_page_list);
|
|
page->flags = SGX_EPC_PAGE_IS_FREE;
|
|
|
|
spin_unlock(&node->lock);
|
|
atomic_long_inc(&sgx_nr_free_pages);
|
|
}
|
|
|
|
static bool __init sgx_setup_epc_section(u64 phys_addr, u64 size,
|
|
unsigned long index,
|
|
struct sgx_epc_section *section)
|
|
{
|
|
unsigned long nr_pages = size >> PAGE_SHIFT;
|
|
unsigned long i;
|
|
|
|
section->virt_addr = memremap(phys_addr, size, MEMREMAP_WB);
|
|
if (!section->virt_addr)
|
|
return false;
|
|
|
|
section->pages = vmalloc(nr_pages * sizeof(struct sgx_epc_page));
|
|
if (!section->pages) {
|
|
memunmap(section->virt_addr);
|
|
return false;
|
|
}
|
|
|
|
section->phys_addr = phys_addr;
|
|
xa_store_range(&sgx_epc_address_space, section->phys_addr,
|
|
phys_addr + size - 1, section, GFP_KERNEL);
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
section->pages[i].section = index;
|
|
section->pages[i].flags = 0;
|
|
section->pages[i].owner = NULL;
|
|
section->pages[i].poison = 0;
|
|
list_add_tail(§ion->pages[i].list, &sgx_dirty_page_list);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool arch_is_platform_page(u64 paddr)
|
|
{
|
|
return !!xa_load(&sgx_epc_address_space, paddr);
|
|
}
|
|
EXPORT_SYMBOL_GPL(arch_is_platform_page);
|
|
|
|
static struct sgx_epc_page *sgx_paddr_to_page(u64 paddr)
|
|
{
|
|
struct sgx_epc_section *section;
|
|
|
|
section = xa_load(&sgx_epc_address_space, paddr);
|
|
if (!section)
|
|
return NULL;
|
|
|
|
return §ion->pages[PFN_DOWN(paddr - section->phys_addr)];
|
|
}
|
|
|
|
/*
|
|
* Called in process context to handle a hardware reported
|
|
* error in an SGX EPC page.
|
|
* If the MF_ACTION_REQUIRED bit is set in flags, then the
|
|
* context is the task that consumed the poison data. Otherwise
|
|
* this is called from a kernel thread unrelated to the page.
|
|
*/
|
|
int arch_memory_failure(unsigned long pfn, int flags)
|
|
{
|
|
struct sgx_epc_page *page = sgx_paddr_to_page(pfn << PAGE_SHIFT);
|
|
struct sgx_epc_section *section;
|
|
struct sgx_numa_node *node;
|
|
|
|
/*
|
|
* mm/memory-failure.c calls this routine for all errors
|
|
* where there isn't a "struct page" for the address. But that
|
|
* includes other address ranges besides SGX.
|
|
*/
|
|
if (!page)
|
|
return -ENXIO;
|
|
|
|
/*
|
|
* If poison was consumed synchronously. Send a SIGBUS to
|
|
* the task. Hardware has already exited the SGX enclave and
|
|
* will not allow re-entry to an enclave that has a memory
|
|
* error. The signal may help the task understand why the
|
|
* enclave is broken.
|
|
*/
|
|
if (flags & MF_ACTION_REQUIRED)
|
|
force_sig(SIGBUS);
|
|
|
|
section = &sgx_epc_sections[page->section];
|
|
node = section->node;
|
|
|
|
spin_lock(&node->lock);
|
|
|
|
/* Already poisoned? Nothing more to do */
|
|
if (page->poison)
|
|
goto out;
|
|
|
|
page->poison = 1;
|
|
|
|
/*
|
|
* If the page is on a free list, move it to the per-node
|
|
* poison page list.
|
|
*/
|
|
if (page->flags & SGX_EPC_PAGE_IS_FREE) {
|
|
list_move(&page->list, &node->sgx_poison_page_list);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* TBD: Add additional plumbing to enable pre-emptive
|
|
* action for asynchronous poison notification. Until
|
|
* then just hope that the poison:
|
|
* a) is not accessed - sgx_free_epc_page() will deal with it
|
|
* when the user gives it back
|
|
* b) results in a recoverable machine check rather than
|
|
* a fatal one
|
|
*/
|
|
out:
|
|
spin_unlock(&node->lock);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* A section metric is concatenated in a way that @low bits 12-31 define the
|
|
* bits 12-31 of the metric and @high bits 0-19 define the bits 32-51 of the
|
|
* metric.
|
|
*/
|
|
static inline u64 __init sgx_calc_section_metric(u64 low, u64 high)
|
|
{
|
|
return (low & GENMASK_ULL(31, 12)) +
|
|
((high & GENMASK_ULL(19, 0)) << 32);
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
static ssize_t sgx_total_bytes_show(struct device *dev, struct device_attribute *attr, char *buf)
|
|
{
|
|
return sysfs_emit(buf, "%lu\n", sgx_numa_nodes[dev->id].size);
|
|
}
|
|
static DEVICE_ATTR_RO(sgx_total_bytes);
|
|
|
|
static umode_t arch_node_attr_is_visible(struct kobject *kobj,
|
|
struct attribute *attr, int idx)
|
|
{
|
|
/* Make all x86/ attributes invisible when SGX is not initialized: */
|
|
if (nodes_empty(sgx_numa_mask))
|
|
return 0;
|
|
|
|
return attr->mode;
|
|
}
|
|
|
|
static struct attribute *arch_node_dev_attrs[] = {
|
|
&dev_attr_sgx_total_bytes.attr,
|
|
NULL,
|
|
};
|
|
|
|
const struct attribute_group arch_node_dev_group = {
|
|
.name = "x86",
|
|
.attrs = arch_node_dev_attrs,
|
|
.is_visible = arch_node_attr_is_visible,
|
|
};
|
|
|
|
static void __init arch_update_sysfs_visibility(int nid)
|
|
{
|
|
struct node *node = node_devices[nid];
|
|
int ret;
|
|
|
|
ret = sysfs_update_group(&node->dev.kobj, &arch_node_dev_group);
|
|
|
|
if (ret)
|
|
pr_err("sysfs update failed (%d), files may be invisible", ret);
|
|
}
|
|
#else /* !CONFIG_NUMA */
|
|
static void __init arch_update_sysfs_visibility(int nid) {}
|
|
#endif
|
|
|
|
static bool __init sgx_page_cache_init(void)
|
|
{
|
|
u32 eax, ebx, ecx, edx, type;
|
|
u64 pa, size;
|
|
int nid;
|
|
int i;
|
|
|
|
sgx_numa_nodes = kmalloc_array(num_possible_nodes(), sizeof(*sgx_numa_nodes), GFP_KERNEL);
|
|
if (!sgx_numa_nodes)
|
|
return false;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(sgx_epc_sections); i++) {
|
|
cpuid_count(SGX_CPUID, i + SGX_CPUID_EPC, &eax, &ebx, &ecx, &edx);
|
|
|
|
type = eax & SGX_CPUID_EPC_MASK;
|
|
if (type == SGX_CPUID_EPC_INVALID)
|
|
break;
|
|
|
|
if (type != SGX_CPUID_EPC_SECTION) {
|
|
pr_err_once("Unknown EPC section type: %u\n", type);
|
|
break;
|
|
}
|
|
|
|
pa = sgx_calc_section_metric(eax, ebx);
|
|
size = sgx_calc_section_metric(ecx, edx);
|
|
|
|
pr_info("EPC section 0x%llx-0x%llx\n", pa, pa + size - 1);
|
|
|
|
if (!sgx_setup_epc_section(pa, size, i, &sgx_epc_sections[i])) {
|
|
pr_err("No free memory for an EPC section\n");
|
|
break;
|
|
}
|
|
|
|
nid = numa_map_to_online_node(phys_to_target_node(pa));
|
|
if (nid == NUMA_NO_NODE) {
|
|
/* The physical address is already printed above. */
|
|
pr_warn(FW_BUG "Unable to map EPC section to online node. Fallback to the NUMA node 0.\n");
|
|
nid = 0;
|
|
}
|
|
|
|
if (!node_isset(nid, sgx_numa_mask)) {
|
|
spin_lock_init(&sgx_numa_nodes[nid].lock);
|
|
INIT_LIST_HEAD(&sgx_numa_nodes[nid].free_page_list);
|
|
INIT_LIST_HEAD(&sgx_numa_nodes[nid].sgx_poison_page_list);
|
|
node_set(nid, sgx_numa_mask);
|
|
sgx_numa_nodes[nid].size = 0;
|
|
|
|
/* Make SGX-specific node sysfs files visible: */
|
|
arch_update_sysfs_visibility(nid);
|
|
}
|
|
|
|
sgx_epc_sections[i].node = &sgx_numa_nodes[nid];
|
|
sgx_numa_nodes[nid].size += size;
|
|
|
|
sgx_nr_epc_sections++;
|
|
}
|
|
|
|
if (!sgx_nr_epc_sections) {
|
|
pr_err("There are zero EPC sections.\n");
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller.
|
|
* Bare-metal driver requires to update them to hash of enclave's signer
|
|
* before EINIT. KVM needs to update them to guest's virtual MSR values
|
|
* before doing EINIT from guest.
|
|
*/
|
|
void sgx_update_lepubkeyhash(u64 *lepubkeyhash)
|
|
{
|
|
int i;
|
|
|
|
WARN_ON_ONCE(preemptible());
|
|
|
|
for (i = 0; i < 4; i++)
|
|
wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]);
|
|
}
|
|
|
|
const struct file_operations sgx_provision_fops = {
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static struct miscdevice sgx_dev_provision = {
|
|
.minor = MISC_DYNAMIC_MINOR,
|
|
.name = "sgx_provision",
|
|
.nodename = "sgx_provision",
|
|
.fops = &sgx_provision_fops,
|
|
};
|
|
|
|
/**
|
|
* sgx_set_attribute() - Update allowed attributes given file descriptor
|
|
* @allowed_attributes: Pointer to allowed enclave attributes
|
|
* @attribute_fd: File descriptor for specific attribute
|
|
*
|
|
* Append enclave attribute indicated by file descriptor to allowed
|
|
* attributes. Currently only SGX_ATTR_PROVISIONKEY indicated by
|
|
* /dev/sgx_provision is supported.
|
|
*
|
|
* Return:
|
|
* -0: SGX_ATTR_PROVISIONKEY is appended to allowed_attributes
|
|
* -EINVAL: Invalid, or not supported file descriptor
|
|
*/
|
|
int sgx_set_attribute(unsigned long *allowed_attributes,
|
|
unsigned int attribute_fd)
|
|
{
|
|
struct fd f = fdget(attribute_fd);
|
|
|
|
if (!f.file)
|
|
return -EINVAL;
|
|
|
|
if (f.file->f_op != &sgx_provision_fops) {
|
|
fdput(f);
|
|
return -EINVAL;
|
|
}
|
|
|
|
*allowed_attributes |= SGX_ATTR_PROVISIONKEY;
|
|
|
|
fdput(f);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(sgx_set_attribute);
|
|
|
|
static int __init sgx_init(void)
|
|
{
|
|
int ret;
|
|
int i;
|
|
|
|
if (!cpu_feature_enabled(X86_FEATURE_SGX))
|
|
return -ENODEV;
|
|
|
|
if (!sgx_page_cache_init())
|
|
return -ENOMEM;
|
|
|
|
if (!sgx_page_reclaimer_init()) {
|
|
ret = -ENOMEM;
|
|
goto err_page_cache;
|
|
}
|
|
|
|
ret = misc_register(&sgx_dev_provision);
|
|
if (ret)
|
|
goto err_kthread;
|
|
|
|
/*
|
|
* Always try to initialize the native *and* KVM drivers.
|
|
* The KVM driver is less picky than the native one and
|
|
* can function if the native one is not supported on the
|
|
* current system or fails to initialize.
|
|
*
|
|
* Error out only if both fail to initialize.
|
|
*/
|
|
ret = sgx_drv_init();
|
|
|
|
if (sgx_vepc_init() && ret)
|
|
goto err_provision;
|
|
|
|
return 0;
|
|
|
|
err_provision:
|
|
misc_deregister(&sgx_dev_provision);
|
|
|
|
err_kthread:
|
|
kthread_stop(ksgxd_tsk);
|
|
|
|
err_page_cache:
|
|
for (i = 0; i < sgx_nr_epc_sections; i++) {
|
|
vfree(sgx_epc_sections[i].pages);
|
|
memunmap(sgx_epc_sections[i].virt_addr);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
device_initcall(sgx_init);
|