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-rw-r--r--drivers/crypto/ccp/ccp-dev.c670
1 files changed, 670 insertions, 0 deletions
diff --git a/drivers/crypto/ccp/ccp-dev.c b/drivers/crypto/ccp/ccp-dev.c
new file mode 100644
index 0000000000..c531d13d97
--- /dev/null
+++ b/drivers/crypto/ccp/ccp-dev.c
@@ -0,0 +1,670 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * AMD Cryptographic Coprocessor (CCP) driver
+ *
+ * Copyright (C) 2013,2019 Advanced Micro Devices, Inc.
+ *
+ * Author: Tom Lendacky <thomas.lendacky@amd.com>
+ * Author: Gary R Hook <gary.hook@amd.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/hw_random.h>
+#include <linux/cpu.h>
+#include <linux/atomic.h>
+#ifdef CONFIG_X86
+#include <asm/cpu_device_id.h>
+#endif
+#include <linux/ccp.h>
+
+#include "ccp-dev.h"
+
+#define MAX_CCPS 32
+
+/* Limit CCP use to a specifed number of queues per device */
+static unsigned int nqueues;
+module_param(nqueues, uint, 0444);
+MODULE_PARM_DESC(nqueues, "Number of queues per CCP (minimum 1; default: all available)");
+
+/* Limit the maximum number of configured CCPs */
+static atomic_t dev_count = ATOMIC_INIT(0);
+static unsigned int max_devs = MAX_CCPS;
+module_param(max_devs, uint, 0444);
+MODULE_PARM_DESC(max_devs, "Maximum number of CCPs to enable (default: all; 0 disables all CCPs)");
+
+struct ccp_tasklet_data {
+ struct completion completion;
+ struct ccp_cmd *cmd;
+};
+
+/* Human-readable error strings */
+#define CCP_MAX_ERROR_CODE 64
+static char *ccp_error_codes[] = {
+ "",
+ "ILLEGAL_ENGINE",
+ "ILLEGAL_KEY_ID",
+ "ILLEGAL_FUNCTION_TYPE",
+ "ILLEGAL_FUNCTION_MODE",
+ "ILLEGAL_FUNCTION_ENCRYPT",
+ "ILLEGAL_FUNCTION_SIZE",
+ "Zlib_MISSING_INIT_EOM",
+ "ILLEGAL_FUNCTION_RSVD",
+ "ILLEGAL_BUFFER_LENGTH",
+ "VLSB_FAULT",
+ "ILLEGAL_MEM_ADDR",
+ "ILLEGAL_MEM_SEL",
+ "ILLEGAL_CONTEXT_ID",
+ "ILLEGAL_KEY_ADDR",
+ "0xF Reserved",
+ "Zlib_ILLEGAL_MULTI_QUEUE",
+ "Zlib_ILLEGAL_JOBID_CHANGE",
+ "CMD_TIMEOUT",
+ "IDMA0_AXI_SLVERR",
+ "IDMA0_AXI_DECERR",
+ "0x15 Reserved",
+ "IDMA1_AXI_SLAVE_FAULT",
+ "IDMA1_AIXI_DECERR",
+ "0x18 Reserved",
+ "ZLIBVHB_AXI_SLVERR",
+ "ZLIBVHB_AXI_DECERR",
+ "0x1B Reserved",
+ "ZLIB_UNEXPECTED_EOM",
+ "ZLIB_EXTRA_DATA",
+ "ZLIB_BTYPE",
+ "ZLIB_UNDEFINED_SYMBOL",
+ "ZLIB_UNDEFINED_DISTANCE_S",
+ "ZLIB_CODE_LENGTH_SYMBOL",
+ "ZLIB _VHB_ILLEGAL_FETCH",
+ "ZLIB_UNCOMPRESSED_LEN",
+ "ZLIB_LIMIT_REACHED",
+ "ZLIB_CHECKSUM_MISMATCH0",
+ "ODMA0_AXI_SLVERR",
+ "ODMA0_AXI_DECERR",
+ "0x28 Reserved",
+ "ODMA1_AXI_SLVERR",
+ "ODMA1_AXI_DECERR",
+};
+
+void ccp_log_error(struct ccp_device *d, unsigned int e)
+{
+ if (WARN_ON(e >= CCP_MAX_ERROR_CODE))
+ return;
+
+ if (e < ARRAY_SIZE(ccp_error_codes))
+ dev_err(d->dev, "CCP error %d: %s\n", e, ccp_error_codes[e]);
+ else
+ dev_err(d->dev, "CCP error %d: Unknown Error\n", e);
+}
+
+/* List of CCPs, CCP count, read-write access lock, and access functions
+ *
+ * Lock structure: get ccp_unit_lock for reading whenever we need to
+ * examine the CCP list. While holding it for reading we can acquire
+ * the RR lock to update the round-robin next-CCP pointer. The unit lock
+ * must be acquired before the RR lock.
+ *
+ * If the unit-lock is acquired for writing, we have total control over
+ * the list, so there's no value in getting the RR lock.
+ */
+static DEFINE_RWLOCK(ccp_unit_lock);
+static LIST_HEAD(ccp_units);
+
+/* Round-robin counter */
+static DEFINE_SPINLOCK(ccp_rr_lock);
+static struct ccp_device *ccp_rr;
+
+/**
+ * ccp_add_device - add a CCP device to the list
+ *
+ * @ccp: ccp_device struct pointer
+ *
+ * Put this CCP on the unit list, which makes it available
+ * for use.
+ *
+ * Returns zero if a CCP device is present, -ENODEV otherwise.
+ */
+void ccp_add_device(struct ccp_device *ccp)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&ccp_unit_lock, flags);
+ list_add_tail(&ccp->entry, &ccp_units);
+ if (!ccp_rr)
+ /* We already have the list lock (we're first) so this
+ * pointer can't change on us. Set its initial value.
+ */
+ ccp_rr = ccp;
+ write_unlock_irqrestore(&ccp_unit_lock, flags);
+}
+
+/**
+ * ccp_del_device - remove a CCP device from the list
+ *
+ * @ccp: ccp_device struct pointer
+ *
+ * Remove this unit from the list of devices. If the next device
+ * up for use is this one, adjust the pointer. If this is the last
+ * device, NULL the pointer.
+ */
+void ccp_del_device(struct ccp_device *ccp)
+{
+ unsigned long flags;
+
+ write_lock_irqsave(&ccp_unit_lock, flags);
+ if (ccp_rr == ccp) {
+ /* ccp_unit_lock is read/write; any read access
+ * will be suspended while we make changes to the
+ * list and RR pointer.
+ */
+ if (list_is_last(&ccp_rr->entry, &ccp_units))
+ ccp_rr = list_first_entry(&ccp_units, struct ccp_device,
+ entry);
+ else
+ ccp_rr = list_next_entry(ccp_rr, entry);
+ }
+ list_del(&ccp->entry);
+ if (list_empty(&ccp_units))
+ ccp_rr = NULL;
+ write_unlock_irqrestore(&ccp_unit_lock, flags);
+}
+
+
+
+int ccp_register_rng(struct ccp_device *ccp)
+{
+ int ret = 0;
+
+ dev_dbg(ccp->dev, "Registering RNG...\n");
+ /* Register an RNG */
+ ccp->hwrng.name = ccp->rngname;
+ ccp->hwrng.read = ccp_trng_read;
+ ret = hwrng_register(&ccp->hwrng);
+ if (ret)
+ dev_err(ccp->dev, "error registering hwrng (%d)\n", ret);
+
+ return ret;
+}
+
+void ccp_unregister_rng(struct ccp_device *ccp)
+{
+ if (ccp->hwrng.name)
+ hwrng_unregister(&ccp->hwrng);
+}
+
+static struct ccp_device *ccp_get_device(void)
+{
+ unsigned long flags;
+ struct ccp_device *dp = NULL;
+
+ /* We round-robin through the unit list.
+ * The (ccp_rr) pointer refers to the next unit to use.
+ */
+ read_lock_irqsave(&ccp_unit_lock, flags);
+ if (!list_empty(&ccp_units)) {
+ spin_lock(&ccp_rr_lock);
+ dp = ccp_rr;
+ if (list_is_last(&ccp_rr->entry, &ccp_units))
+ ccp_rr = list_first_entry(&ccp_units, struct ccp_device,
+ entry);
+ else
+ ccp_rr = list_next_entry(ccp_rr, entry);
+ spin_unlock(&ccp_rr_lock);
+ }
+ read_unlock_irqrestore(&ccp_unit_lock, flags);
+
+ return dp;
+}
+
+/**
+ * ccp_present - check if a CCP device is present
+ *
+ * Returns zero if a CCP device is present, -ENODEV otherwise.
+ */
+int ccp_present(void)
+{
+ unsigned long flags;
+ int ret;
+
+ read_lock_irqsave(&ccp_unit_lock, flags);
+ ret = list_empty(&ccp_units);
+ read_unlock_irqrestore(&ccp_unit_lock, flags);
+
+ return ret ? -ENODEV : 0;
+}
+EXPORT_SYMBOL_GPL(ccp_present);
+
+/**
+ * ccp_version - get the version of the CCP device
+ *
+ * Returns the version from the first unit on the list;
+ * otherwise a zero if no CCP device is present
+ */
+unsigned int ccp_version(void)
+{
+ struct ccp_device *dp;
+ unsigned long flags;
+ int ret = 0;
+
+ read_lock_irqsave(&ccp_unit_lock, flags);
+ if (!list_empty(&ccp_units)) {
+ dp = list_first_entry(&ccp_units, struct ccp_device, entry);
+ ret = dp->vdata->version;
+ }
+ read_unlock_irqrestore(&ccp_unit_lock, flags);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ccp_version);
+
+/**
+ * ccp_enqueue_cmd - queue an operation for processing by the CCP
+ *
+ * @cmd: ccp_cmd struct to be processed
+ *
+ * Queue a cmd to be processed by the CCP. If queueing the cmd
+ * would exceed the defined length of the cmd queue the cmd will
+ * only be queued if the CCP_CMD_MAY_BACKLOG flag is set and will
+ * result in a return code of -EBUSY.
+ *
+ * The callback routine specified in the ccp_cmd struct will be
+ * called to notify the caller of completion (if the cmd was not
+ * backlogged) or advancement out of the backlog. If the cmd has
+ * advanced out of the backlog the "err" value of the callback
+ * will be -EINPROGRESS. Any other "err" value during callback is
+ * the result of the operation.
+ *
+ * The cmd has been successfully queued if:
+ * the return code is -EINPROGRESS or
+ * the return code is -EBUSY and CCP_CMD_MAY_BACKLOG flag is set
+ */
+int ccp_enqueue_cmd(struct ccp_cmd *cmd)
+{
+ struct ccp_device *ccp;
+ unsigned long flags;
+ unsigned int i;
+ int ret;
+
+ /* Some commands might need to be sent to a specific device */
+ ccp = cmd->ccp ? cmd->ccp : ccp_get_device();
+
+ if (!ccp)
+ return -ENODEV;
+
+ /* Caller must supply a callback routine */
+ if (!cmd->callback)
+ return -EINVAL;
+
+ cmd->ccp = ccp;
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ i = ccp->cmd_q_count;
+
+ if (ccp->cmd_count >= MAX_CMD_QLEN) {
+ if (cmd->flags & CCP_CMD_MAY_BACKLOG) {
+ ret = -EBUSY;
+ list_add_tail(&cmd->entry, &ccp->backlog);
+ } else {
+ ret = -ENOSPC;
+ }
+ } else {
+ ret = -EINPROGRESS;
+ ccp->cmd_count++;
+ list_add_tail(&cmd->entry, &ccp->cmd);
+
+ /* Find an idle queue */
+ if (!ccp->suspending) {
+ for (i = 0; i < ccp->cmd_q_count; i++) {
+ if (ccp->cmd_q[i].active)
+ continue;
+
+ break;
+ }
+ }
+ }
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+
+ /* If we found an idle queue, wake it up */
+ if (i < ccp->cmd_q_count)
+ wake_up_process(ccp->cmd_q[i].kthread);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ccp_enqueue_cmd);
+
+static void ccp_do_cmd_backlog(struct work_struct *work)
+{
+ struct ccp_cmd *cmd = container_of(work, struct ccp_cmd, work);
+ struct ccp_device *ccp = cmd->ccp;
+ unsigned long flags;
+ unsigned int i;
+
+ cmd->callback(cmd->data, -EINPROGRESS);
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ ccp->cmd_count++;
+ list_add_tail(&cmd->entry, &ccp->cmd);
+
+ /* Find an idle queue */
+ for (i = 0; i < ccp->cmd_q_count; i++) {
+ if (ccp->cmd_q[i].active)
+ continue;
+
+ break;
+ }
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+
+ /* If we found an idle queue, wake it up */
+ if (i < ccp->cmd_q_count)
+ wake_up_process(ccp->cmd_q[i].kthread);
+}
+
+static struct ccp_cmd *ccp_dequeue_cmd(struct ccp_cmd_queue *cmd_q)
+{
+ struct ccp_device *ccp = cmd_q->ccp;
+ struct ccp_cmd *cmd = NULL;
+ struct ccp_cmd *backlog = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ cmd_q->active = 0;
+
+ if (ccp->suspending) {
+ cmd_q->suspended = 1;
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+ wake_up_interruptible(&ccp->suspend_queue);
+
+ return NULL;
+ }
+
+ if (ccp->cmd_count) {
+ cmd_q->active = 1;
+
+ cmd = list_first_entry(&ccp->cmd, struct ccp_cmd, entry);
+ list_del(&cmd->entry);
+
+ ccp->cmd_count--;
+ }
+
+ if (!list_empty(&ccp->backlog)) {
+ backlog = list_first_entry(&ccp->backlog, struct ccp_cmd,
+ entry);
+ list_del(&backlog->entry);
+ }
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+
+ if (backlog) {
+ INIT_WORK(&backlog->work, ccp_do_cmd_backlog);
+ schedule_work(&backlog->work);
+ }
+
+ return cmd;
+}
+
+static void ccp_do_cmd_complete(unsigned long data)
+{
+ struct ccp_tasklet_data *tdata = (struct ccp_tasklet_data *)data;
+ struct ccp_cmd *cmd = tdata->cmd;
+
+ cmd->callback(cmd->data, cmd->ret);
+
+ complete(&tdata->completion);
+}
+
+/**
+ * ccp_cmd_queue_thread - create a kernel thread to manage a CCP queue
+ *
+ * @data: thread-specific data
+ */
+int ccp_cmd_queue_thread(void *data)
+{
+ struct ccp_cmd_queue *cmd_q = (struct ccp_cmd_queue *)data;
+ struct ccp_cmd *cmd;
+ struct ccp_tasklet_data tdata;
+ struct tasklet_struct tasklet;
+
+ tasklet_init(&tasklet, ccp_do_cmd_complete, (unsigned long)&tdata);
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ while (!kthread_should_stop()) {
+ schedule();
+
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ cmd = ccp_dequeue_cmd(cmd_q);
+ if (!cmd)
+ continue;
+
+ __set_current_state(TASK_RUNNING);
+
+ /* Execute the command */
+ cmd->ret = ccp_run_cmd(cmd_q, cmd);
+
+ /* Schedule the completion callback */
+ tdata.cmd = cmd;
+ init_completion(&tdata.completion);
+ tasklet_schedule(&tasklet);
+ wait_for_completion(&tdata.completion);
+ }
+
+ __set_current_state(TASK_RUNNING);
+
+ return 0;
+}
+
+/**
+ * ccp_alloc_struct - allocate and initialize the ccp_device struct
+ *
+ * @sp: sp_device struct of the CCP
+ */
+struct ccp_device *ccp_alloc_struct(struct sp_device *sp)
+{
+ struct device *dev = sp->dev;
+ struct ccp_device *ccp;
+
+ ccp = devm_kzalloc(dev, sizeof(*ccp), GFP_KERNEL);
+ if (!ccp)
+ return NULL;
+ ccp->dev = dev;
+ ccp->sp = sp;
+ ccp->axcache = sp->axcache;
+
+ INIT_LIST_HEAD(&ccp->cmd);
+ INIT_LIST_HEAD(&ccp->backlog);
+
+ spin_lock_init(&ccp->cmd_lock);
+ mutex_init(&ccp->req_mutex);
+ mutex_init(&ccp->sb_mutex);
+ ccp->sb_count = KSB_COUNT;
+ ccp->sb_start = 0;
+
+ /* Initialize the wait queues */
+ init_waitqueue_head(&ccp->sb_queue);
+ init_waitqueue_head(&ccp->suspend_queue);
+
+ snprintf(ccp->name, MAX_CCP_NAME_LEN, "ccp-%u", sp->ord);
+ snprintf(ccp->rngname, MAX_CCP_NAME_LEN, "ccp-%u-rng", sp->ord);
+
+ return ccp;
+}
+
+int ccp_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+ struct ccp_device *ccp = container_of(rng, struct ccp_device, hwrng);
+ u32 trng_value;
+ int len = min_t(int, sizeof(trng_value), max);
+
+ /* Locking is provided by the caller so we can update device
+ * hwrng-related fields safely
+ */
+ trng_value = ioread32(ccp->io_regs + TRNG_OUT_REG);
+ if (!trng_value) {
+ /* Zero is returned if not data is available or if a
+ * bad-entropy error is present. Assume an error if
+ * we exceed TRNG_RETRIES reads of zero.
+ */
+ if (ccp->hwrng_retries++ > TRNG_RETRIES)
+ return -EIO;
+
+ return 0;
+ }
+
+ /* Reset the counter and save the rng value */
+ ccp->hwrng_retries = 0;
+ memcpy(data, &trng_value, len);
+
+ return len;
+}
+
+bool ccp_queues_suspended(struct ccp_device *ccp)
+{
+ unsigned int suspended = 0;
+ unsigned long flags;
+ unsigned int i;
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ for (i = 0; i < ccp->cmd_q_count; i++)
+ if (ccp->cmd_q[i].suspended)
+ suspended++;
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+
+ return ccp->cmd_q_count == suspended;
+}
+
+void ccp_dev_suspend(struct sp_device *sp)
+{
+ struct ccp_device *ccp = sp->ccp_data;
+ unsigned long flags;
+ unsigned int i;
+
+ /* If there's no device there's nothing to do */
+ if (!ccp)
+ return;
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ ccp->suspending = 1;
+
+ /* Wake all the queue kthreads to prepare for suspend */
+ for (i = 0; i < ccp->cmd_q_count; i++)
+ wake_up_process(ccp->cmd_q[i].kthread);
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+
+ /* Wait for all queue kthreads to say they're done */
+ while (!ccp_queues_suspended(ccp))
+ wait_event_interruptible(ccp->suspend_queue,
+ ccp_queues_suspended(ccp));
+}
+
+void ccp_dev_resume(struct sp_device *sp)
+{
+ struct ccp_device *ccp = sp->ccp_data;
+ unsigned long flags;
+ unsigned int i;
+
+ /* If there's no device there's nothing to do */
+ if (!ccp)
+ return;
+
+ spin_lock_irqsave(&ccp->cmd_lock, flags);
+
+ ccp->suspending = 0;
+
+ /* Wake up all the kthreads */
+ for (i = 0; i < ccp->cmd_q_count; i++) {
+ ccp->cmd_q[i].suspended = 0;
+ wake_up_process(ccp->cmd_q[i].kthread);
+ }
+
+ spin_unlock_irqrestore(&ccp->cmd_lock, flags);
+}
+
+int ccp_dev_init(struct sp_device *sp)
+{
+ struct device *dev = sp->dev;
+ struct ccp_device *ccp;
+ int ret;
+
+ /*
+ * Check how many we have so far, and stop after reaching
+ * that number
+ */
+ if (atomic_inc_return(&dev_count) > max_devs)
+ return 0; /* don't fail the load */
+
+ ret = -ENOMEM;
+ ccp = ccp_alloc_struct(sp);
+ if (!ccp)
+ goto e_err;
+ sp->ccp_data = ccp;
+
+ if (!nqueues || (nqueues > MAX_HW_QUEUES))
+ ccp->max_q_count = MAX_HW_QUEUES;
+ else
+ ccp->max_q_count = nqueues;
+
+ ccp->vdata = (struct ccp_vdata *)sp->dev_vdata->ccp_vdata;
+ if (!ccp->vdata || !ccp->vdata->version) {
+ ret = -ENODEV;
+ dev_err(dev, "missing driver data\n");
+ goto e_err;
+ }
+
+ ccp->use_tasklet = sp->use_tasklet;
+
+ ccp->io_regs = sp->io_map + ccp->vdata->offset;
+ if (ccp->vdata->setup)
+ ccp->vdata->setup(ccp);
+
+ ret = ccp->vdata->perform->init(ccp);
+ if (ret) {
+ /* A positive number means that the device cannot be initialized,
+ * but no additional message is required.
+ */
+ if (ret > 0)
+ goto e_quiet;
+
+ /* An unexpected problem occurred, and should be reported in the log */
+ goto e_err;
+ }
+
+ dev_notice(dev, "ccp enabled\n");
+
+ return 0;
+
+e_err:
+ dev_notice(dev, "ccp initialization failed\n");
+
+e_quiet:
+ sp->ccp_data = NULL;
+
+ return ret;
+}
+
+void ccp_dev_destroy(struct sp_device *sp)
+{
+ struct ccp_device *ccp = sp->ccp_data;
+
+ if (!ccp)
+ return;
+
+ ccp->vdata->perform->destroy(ccp);
+}