diff options
Diffstat (limited to 'drivers/s390/crypto/ap_bus.c')
| -rw-r--r-- | drivers/s390/crypto/ap_bus.c | 1221 |
1 files changed, 1221 insertions, 0 deletions
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c new file mode 100644 index 00000000000..6ed0985c0c9 --- /dev/null +++ b/drivers/s390/crypto/ap_bus.c @@ -0,0 +1,1221 @@ +/* + * linux/drivers/s390/crypto/ap_bus.c + * + * Copyright (C) 2006 IBM Corporation + * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com> + * Martin Schwidefsky <schwidefsky@de.ibm.com> + * Ralph Wuerthner <rwuerthn@de.ibm.com> + * + * Adjunct processor bus. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/workqueue.h> +#include <linux/notifier.h> +#include <linux/kthread.h> +#include <linux/mutex.h> +#include <asm/s390_rdev.h> + +#include "ap_bus.h" + +/* Some prototypes. */ +static void ap_scan_bus(void *); +static void ap_poll_all(unsigned long); +static void ap_poll_timeout(unsigned long); +static int ap_poll_thread_start(void); +static void ap_poll_thread_stop(void); + +/** + * Module description. + */ +MODULE_AUTHOR("IBM Corporation"); +MODULE_DESCRIPTION("Adjunct Processor Bus driver, " + "Copyright 2006 IBM Corporation"); +MODULE_LICENSE("GPL"); + +/** + * Module parameter + */ +int ap_domain_index = -1; /* Adjunct Processor Domain Index */ +module_param_named(domain, ap_domain_index, int, 0000); +MODULE_PARM_DESC(domain, "domain index for ap devices"); +EXPORT_SYMBOL(ap_domain_index); + +static int ap_thread_flag = 1; +module_param_named(poll_thread, ap_thread_flag, int, 0000); +MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 1 (on)."); + +static struct device *ap_root_device = NULL; + +/** + * Workqueue & timer for bus rescan. + */ +static struct workqueue_struct *ap_work_queue; +static struct timer_list ap_config_timer; +static int ap_config_time = AP_CONFIG_TIME; +static DECLARE_WORK(ap_config_work, ap_scan_bus, NULL); + +/** + * Tasklet & timer for AP request polling. + */ +static struct timer_list ap_poll_timer = TIMER_INITIALIZER(ap_poll_timeout,0,0); +static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0); +static atomic_t ap_poll_requests = ATOMIC_INIT(0); +static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait); +static struct task_struct *ap_poll_kthread = NULL; +static DEFINE_MUTEX(ap_poll_thread_mutex); + +/** + * Test if ap instructions are available. + * + * Returns 0 if the ap instructions are installed. + */ +static inline int ap_instructions_available(void) +{ + register unsigned long reg0 asm ("0") = AP_MKQID(0,0); + register unsigned long reg1 asm ("1") = -ENODEV; + register unsigned long reg2 asm ("2") = 0UL; + + asm volatile( + " .long 0xb2af0000\n" /* PQAP(TAPQ) */ + "0: la %1,0\n" + "1:\n" + EX_TABLE(0b, 1b) + : "+d" (reg0), "+d" (reg1), "+d" (reg2) : : "cc" ); + return reg1; +} + +/** + * Test adjunct processor queue. + * @qid: the ap queue number + * @queue_depth: pointer to queue depth value + * @device_type: pointer to device type value + * + * Returns ap queue status structure. + */ +static inline struct ap_queue_status +ap_test_queue(ap_qid_t qid, int *queue_depth, int *device_type) +{ + register unsigned long reg0 asm ("0") = qid; + register struct ap_queue_status reg1 asm ("1"); + register unsigned long reg2 asm ("2") = 0UL; + + asm volatile(".long 0xb2af0000" /* PQAP(TAPQ) */ + : "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc"); + *device_type = (int) (reg2 >> 24); + *queue_depth = (int) (reg2 & 0xff); + return reg1; +} + +/** + * Reset adjunct processor queue. + * @qid: the ap queue number + * + * Returns ap queue status structure. + */ +static inline struct ap_queue_status ap_reset_queue(ap_qid_t qid) +{ + register unsigned long reg0 asm ("0") = qid | 0x01000000UL; + register struct ap_queue_status reg1 asm ("1"); + register unsigned long reg2 asm ("2") = 0UL; + + asm volatile( + ".long 0xb2af0000" /* PQAP(RAPQ) */ + : "+d" (reg0), "=d" (reg1), "+d" (reg2) : : "cc"); + return reg1; +} + +/** + * Send message to adjunct processor queue. + * @qid: the ap queue number + * @psmid: the program supplied message identifier + * @msg: the message text + * @length: the message length + * + * Returns ap queue status structure. + * + * Condition code 1 on NQAP can't happen because the L bit is 1. + * + * Condition code 2 on NQAP also means the send is incomplete, + * because a segment boundary was reached. The NQAP is repeated. + */ +static inline struct ap_queue_status +__ap_send(ap_qid_t qid, unsigned long long psmid, void *msg, size_t length) +{ + typedef struct { char _[length]; } msgblock; + register unsigned long reg0 asm ("0") = qid | 0x40000000UL; + register struct ap_queue_status reg1 asm ("1"); + register unsigned long reg2 asm ("2") = (unsigned long) msg; + register unsigned long reg3 asm ("3") = (unsigned long) length; + register unsigned long reg4 asm ("4") = (unsigned int) (psmid >> 32); + register unsigned long reg5 asm ("5") = (unsigned int) psmid; + + asm volatile ( + "0: .long 0xb2ad0042\n" /* DQAP */ + " brc 2,0b" + : "+d" (reg0), "=d" (reg1), "+d" (reg2), "+d" (reg3) + : "d" (reg4), "d" (reg5), "m" (*(msgblock *) msg) + : "cc" ); + return reg1; +} + +int ap_send(ap_qid_t qid, unsigned long long psmid, void *msg, size_t length) +{ + struct ap_queue_status status; + + status = __ap_send(qid, psmid, msg, length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + return 0; + case AP_RESPONSE_Q_FULL: + return -EBUSY; + default: /* Device is gone. */ + return -ENODEV; + } +} +EXPORT_SYMBOL(ap_send); + +/* + * Receive message from adjunct processor queue. + * @qid: the ap queue number + * @psmid: pointer to program supplied message identifier + * @msg: the message text + * @length: the message length + * + * Returns ap queue status structure. + * + * Condition code 1 on DQAP means the receive has taken place + * but only partially. The response is incomplete, hence the + * DQAP is repeated. + * + * Condition code 2 on DQAP also means the receive is incomplete, + * this time because a segment boundary was reached. Again, the + * DQAP is repeated. + * + * Note that gpr2 is used by the DQAP instruction to keep track of + * any 'residual' length, in case the instruction gets interrupted. + * Hence it gets zeroed before the instruction. + */ +static inline struct ap_queue_status +__ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length) +{ + typedef struct { char _[length]; } msgblock; + register unsigned long reg0 asm("0") = qid | 0x80000000UL; + register struct ap_queue_status reg1 asm ("1"); + register unsigned long reg2 asm("2") = 0UL; + register unsigned long reg4 asm("4") = (unsigned long) msg; + register unsigned long reg5 asm("5") = (unsigned long) length; + register unsigned long reg6 asm("6") = 0UL; + register unsigned long reg7 asm("7") = 0UL; + + + asm volatile( + "0: .long 0xb2ae0064\n" + " brc 6,0b\n" + : "+d" (reg0), "=d" (reg1), "+d" (reg2), + "+d" (reg4), "+d" (reg5), "+d" (reg6), "+d" (reg7), + "=m" (*(msgblock *) msg) : : "cc" ); + *psmid = (((unsigned long long) reg6) << 32) + reg7; + return reg1; +} + +int ap_recv(ap_qid_t qid, unsigned long long *psmid, void *msg, size_t length) +{ + struct ap_queue_status status; + + status = __ap_recv(qid, psmid, msg, length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + return 0; + case AP_RESPONSE_NO_PENDING_REPLY: + if (status.queue_empty) + return -ENOENT; + return -EBUSY; + default: + return -ENODEV; + } +} +EXPORT_SYMBOL(ap_recv); + +/** + * Check if an AP queue is available. The test is repeated for + * AP_MAX_RESET times. + * @qid: the ap queue number + * @queue_depth: pointer to queue depth value + * @device_type: pointer to device type value + */ +static int ap_query_queue(ap_qid_t qid, int *queue_depth, int *device_type) +{ + struct ap_queue_status status; + int t_depth, t_device_type, rc, i; + + rc = -EBUSY; + for (i = 0; i < AP_MAX_RESET; i++) { + status = ap_test_queue(qid, &t_depth, &t_device_type); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + *queue_depth = t_depth + 1; + *device_type = t_device_type; + rc = 0; + break; + case AP_RESPONSE_Q_NOT_AVAIL: + rc = -ENODEV; + break; + case AP_RESPONSE_RESET_IN_PROGRESS: + break; + case AP_RESPONSE_DECONFIGURED: + rc = -ENODEV; + break; + case AP_RESPONSE_CHECKSTOPPED: + rc = -ENODEV; + break; + case AP_RESPONSE_BUSY: + break; + default: + BUG(); + } + if (rc != -EBUSY) + break; + if (i < AP_MAX_RESET - 1) + udelay(5); + } + return rc; +} + +/** + * Reset an AP queue and wait for it to become available again. + * @qid: the ap queue number + */ +static int ap_init_queue(ap_qid_t qid) +{ + struct ap_queue_status status; + int rc, dummy, i; + + rc = -ENODEV; + status = ap_reset_queue(qid); + for (i = 0; i < AP_MAX_RESET; i++) { + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + if (status.queue_empty) + rc = 0; + break; + case AP_RESPONSE_Q_NOT_AVAIL: + case AP_RESPONSE_DECONFIGURED: + case AP_RESPONSE_CHECKSTOPPED: + i = AP_MAX_RESET; /* return with -ENODEV */ + break; + case AP_RESPONSE_RESET_IN_PROGRESS: + case AP_RESPONSE_BUSY: + default: + break; + } + if (rc != -ENODEV) + break; + if (i < AP_MAX_RESET - 1) { + udelay(5); + status = ap_test_queue(qid, &dummy, &dummy); + } + } + return rc; +} + +/** + * AP device related attributes. + */ +static ssize_t ap_hwtype_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->device_type); +} +static DEVICE_ATTR(hwtype, 0444, ap_hwtype_show, NULL); + +static ssize_t ap_depth_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + return snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->queue_depth); +} +static DEVICE_ATTR(depth, 0444, ap_depth_show, NULL); + +static ssize_t ap_request_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + int rc; + + spin_lock_bh(&ap_dev->lock); + rc = snprintf(buf, PAGE_SIZE, "%d\n", ap_dev->total_request_count); + spin_unlock_bh(&ap_dev->lock); + return rc; +} + +static DEVICE_ATTR(request_count, 0444, ap_request_count_show, NULL); + +static ssize_t ap_modalias_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "ap:t%02X", to_ap_dev(dev)->device_type); +} + +static DEVICE_ATTR(modalias, 0444, ap_modalias_show, NULL); + +static struct attribute *ap_dev_attrs[] = { + &dev_attr_hwtype.attr, + &dev_attr_depth.attr, + &dev_attr_request_count.attr, + &dev_attr_modalias.attr, + NULL +}; +static struct attribute_group ap_dev_attr_group = { + .attrs = ap_dev_attrs +}; + +/** + * AP bus driver registration/unregistration. + */ +static int ap_bus_match(struct device *dev, struct device_driver *drv) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + struct ap_driver *ap_drv = to_ap_drv(drv); + struct ap_device_id *id; + + /** + * Compare device type of the device with the list of + * supported types of the device_driver. + */ + for (id = ap_drv->ids; id->match_flags; id++) { + if ((id->match_flags & AP_DEVICE_ID_MATCH_DEVICE_TYPE) && + (id->dev_type != ap_dev->device_type)) + continue; + return 1; + } + return 0; +} + +/** + * uevent function for AP devices. It sets up a single environment + * variable DEV_TYPE which contains the hardware device type. + */ +static int ap_uevent (struct device *dev, char **envp, int num_envp, + char *buffer, int buffer_size) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + int length; + + if (!ap_dev) + return -ENODEV; + + /* Set up DEV_TYPE environment variable. */ + envp[0] = buffer; + length = scnprintf(buffer, buffer_size, "DEV_TYPE=%04X", + ap_dev->device_type); + if (buffer_size - length <= 0) + return -ENOMEM; + envp[1] = 0; + return 0; +} + +static struct bus_type ap_bus_type = { + .name = "ap", + .match = &ap_bus_match, + .uevent = &ap_uevent, +}; + +static int ap_device_probe(struct device *dev) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + struct ap_driver *ap_drv = to_ap_drv(dev->driver); + int rc; + + ap_dev->drv = ap_drv; + rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV; + if (rc) + ap_dev->unregistered = 1; + return rc; +} + +/** + * Flush all requests from the request/pending queue of an AP device. + * @ap_dev: pointer to the AP device. + */ +static inline void __ap_flush_queue(struct ap_device *ap_dev) +{ + struct ap_message *ap_msg, *next; + + list_for_each_entry_safe(ap_msg, next, &ap_dev->pendingq, list) { + list_del_init(&ap_msg->list); + ap_dev->pendingq_count--; + ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV)); + } + list_for_each_entry_safe(ap_msg, next, &ap_dev->requestq, list) { + list_del_init(&ap_msg->list); + ap_dev->requestq_count--; + ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV)); + } +} + +void ap_flush_queue(struct ap_device *ap_dev) +{ + spin_lock_bh(&ap_dev->lock); + __ap_flush_queue(ap_dev); + spin_unlock_bh(&ap_dev->lock); +} +EXPORT_SYMBOL(ap_flush_queue); + +static int ap_device_remove(struct device *dev) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + struct ap_driver *ap_drv = ap_dev->drv; + + spin_lock_bh(&ap_dev->lock); + __ap_flush_queue(ap_dev); + /** + * set ->unregistered to 1 while holding the lock. This prevents + * new messages to be put on the queue from now on. + */ + ap_dev->unregistered = 1; + spin_unlock_bh(&ap_dev->lock); + if (ap_drv->remove) + ap_drv->remove(ap_dev); + return 0; +} + +int ap_driver_register(struct ap_driver *ap_drv, struct module *owner, + char *name) +{ + struct device_driver *drv = &ap_drv->driver; + + drv->bus = &ap_bus_type; + drv->probe = ap_device_probe; + drv->remove = ap_device_remove; + drv->owner = owner; + drv->name = name; + return driver_register(drv); +} +EXPORT_SYMBOL(ap_driver_register); + +void ap_driver_unregister(struct ap_driver *ap_drv) +{ + driver_unregister(&ap_drv->driver); +} +EXPORT_SYMBOL(ap_driver_unregister); + +/** + * AP bus attributes. + */ +static ssize_t ap_domain_show(struct bus_type *bus, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", ap_domain_index); +} + +static BUS_ATTR(ap_domain, 0444, ap_domain_show, NULL); + +static ssize_t ap_config_time_show(struct bus_type *bus, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time); +} + +static ssize_t ap_config_time_store(struct bus_type *bus, + const char *buf, size_t count) +{ + int time; + + if (sscanf(buf, "%d\n", &time) != 1 || time < 5 || time > 120) + return -EINVAL; + ap_config_time = time; + if (!timer_pending(&ap_config_timer) || + !mod_timer(&ap_config_timer, jiffies + ap_config_time * HZ)) { + ap_config_timer.expires = jiffies + ap_config_time * HZ; + add_timer(&ap_config_timer); + } + return count; +} + +static BUS_ATTR(config_time, 0644, ap_config_time_show, ap_config_time_store); + +static ssize_t ap_poll_thread_show(struct bus_type *bus, char *buf) +{ + return snprintf(buf, PAGE_SIZE, "%d\n", ap_poll_kthread ? 1 : 0); +} + +static ssize_t ap_poll_thread_store(struct bus_type *bus, + const char *buf, size_t count) +{ + int flag, rc; + + if (sscanf(buf, "%d\n", &flag) != 1) + return -EINVAL; + if (flag) { + rc = ap_poll_thread_start(); + if (rc) + return rc; + } + else + ap_poll_thread_stop(); + return count; +} + +static BUS_ATTR(poll_thread, 0644, ap_poll_thread_show, ap_poll_thread_store); + +static struct bus_attribute *const ap_bus_attrs[] = { + &bus_attr_ap_domain, + &bus_attr_config_time, + &bus_attr_poll_thread, + NULL +}; + +/** + * Pick one of the 16 ap domains. + */ +static inline int ap_select_domain(void) +{ + int queue_depth, device_type, count, max_count, best_domain; + int rc, i, j; + + /** + * We want to use a single domain. Either the one specified with + * the "domain=" parameter or the domain with the maximum number + * of devices. + */ + if (ap_domain_index >= 0 && ap_domain_index < AP_DOMAINS) + /* Domain has already been selected. */ + return 0; + best_domain = -1; + max_count = 0; + for (i = 0; i < AP_DOMAINS; i++) { + count = 0; + for (j = 0; j < AP_DEVICES; j++) { + ap_qid_t qid = AP_MKQID(j, i); + rc = ap_query_queue(qid, &queue_depth, &device_type); + if (rc) + continue; + count++; + } + if (count > max_count) { + max_count = count; + best_domain = i; + } + } + if (best_domain >= 0){ + ap_domain_index = best_domain; + return 0; + } + return -ENODEV; +} + +/** + * Find the device type if query queue returned a device type of 0. + * @ap_dev: pointer to the AP device. + */ +static int ap_probe_device_type(struct ap_device *ap_dev) +{ + static unsigned char msg[] = { + 0x00,0x06,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x58,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x01,0x00,0x43,0x43,0x41,0x2d,0x41,0x50, + 0x50,0x4c,0x20,0x20,0x20,0x01,0x01,0x01, + 0x00,0x00,0x00,0x00,0x50,0x4b,0x00,0x00, + 0x00,0x00,0x01,0x1c,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x05,0xb8,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x70,0x00,0x41,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x54,0x32,0x01,0x00,0xa0,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0xb8,0x05,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x0a,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00, + 0x00,0x00,0x00,0x00,0x00,0x00,0x08,0x00, + 0x49,0x43,0x53,0x46,0x20,0x20,0x20,0x20, + 0x50,0x4b,0x0a,0x00,0x50,0x4b,0x43,0x53, + 0x2d,0x31,0x2e,0x32,0x37,0x00,0x11,0x22, + 0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00, + 0x11,0x22,0x33,0x44,0x55,0x66,0x77,0x88, + 0x99,0x00,0x11,0x22,0x33,0x44,0x55,0x66, + 0x77,0x88,0x99,0x00,0x11,0x22,0x33,0x44, + 0x55,0x66,0x77,0x88,0x99,0x00,0x11,0x22, + 0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00, + 0x11,0x22,0x33,0x5d,0x00,0x5b,0x00,0x77, + 0x88,0x1e,0x00,0x00,0x57,0x00,0x00,0x00, + 0x00,0x04,0x00,0x00,0x4f,0x00,0x00,0x00, + 0x03,0x02,0x00,0x00,0x40,0x01,0x00,0x01, + 0xce,0x02,0x68,0x2d,0x5f,0xa9,0xde,0x0c, + 0xf6,0xd2,0x7b,0x58,0x4b,0xf9,0x28,0x68, + 0x3d,0xb4,0xf4,0xef,0x78,0xd5,0xbe,0x66, + 0x63,0x42,0xef,0xf8,0xfd,0xa4,0xf8,0xb0, + 0x8e,0x29,0xc2,0xc9,0x2e,0xd8,0x45,0xb8, + 0x53,0x8c,0x6f,0x4e,0x72,0x8f,0x6c,0x04, + 0x9c,0x88,0xfc,0x1e,0xc5,0x83,0x55,0x57, + 0xf7,0xdd,0xfd,0x4f,0x11,0x36,0x95,0x5d, + }; + struct ap_queue_status status; + unsigned long long psmid; + char *reply; + int rc, i; + + reply = (void *) get_zeroed_page(GFP_KERNEL); + if (!reply) { + rc = -ENOMEM; + goto out; + } + + status = __ap_send(ap_dev->qid, 0x0102030405060708ULL, + msg, sizeof(msg)); + if (status.response_code != AP_RESPONSE_NORMAL) { + rc = -ENODEV; + goto out_free; + } + + /* Wait for the test message to complete. */ + for (i = 0; i < 6; i++) { + mdelay(300); + status = __ap_recv(ap_dev->qid, &psmid, reply, 4096); + if (status.response_code == AP_RESPONSE_NORMAL && + psmid == 0x0102030405060708ULL) + break; + } + if (i < 6) { + /* Got an answer. */ + if (reply[0] == 0x00 && reply[1] == 0x86) + ap_dev->device_type = AP_DEVICE_TYPE_PCICC; + else + ap_dev->device_type = AP_DEVICE_TYPE_PCICA; + rc = 0; + } else + rc = -ENODEV; + +out_free: + free_page((unsigned long) reply); +out: + return rc; +} + +/** + * Scan the ap bus for new devices. + */ +static int __ap_scan_bus(struct device *dev, void *data) +{ + return to_ap_dev(dev)->qid == (ap_qid_t)(unsigned long) data; +} + +static void ap_device_release(struct device *dev) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + + kfree(ap_dev); +} + +static void ap_scan_bus(void *data) +{ + struct ap_device *ap_dev; + struct device *dev; + ap_qid_t qid; + int queue_depth, device_type; + int rc, i; + + if (ap_select_domain() != 0) + return; + for (i = 0; i < AP_DEVICES; i++) { + qid = AP_MKQID(i, ap_domain_index); + dev = bus_find_device(&ap_bus_type, NULL, + (void *)(unsigned long)qid, + __ap_scan_bus); + if (dev) { + put_device(dev); + continue; + } + rc = ap_query_queue(qid, &queue_depth, &device_type); + if (rc) + continue; + rc = ap_init_queue(qid); + if (rc) + continue; + ap_dev = kzalloc(sizeof(*ap_dev), GFP_KERNEL); + if (!ap_dev) + break; + ap_dev->qid = qid; + ap_dev->queue_depth = queue_depth; + spin_lock_init(&ap_dev->lock); + INIT_LIST_HEAD(&ap_dev->pendingq); + INIT_LIST_HEAD(&ap_dev->requestq); + if (device_type == 0) + ap_probe_device_type(ap_dev); + else + ap_dev->device_type = device_type; + + ap_dev->device.bus = &ap_bus_type; + ap_dev->device.parent = ap_root_device; + snprintf(ap_dev->device.bus_id, BUS_ID_SIZE, "card%02x", + AP_QID_DEVICE(ap_dev->qid)); + ap_dev->device.release = ap_device_release; + rc = device_register(&ap_dev->device); + if (rc) { + kfree(ap_dev); + continue; + } + /* Add device attributes. */ + rc = sysfs_create_group(&ap_dev->device.kobj, + &ap_dev_attr_group); + if (rc) + device_unregister(&ap_dev->device); + } +} + +static void +ap_config_timeout(unsigned long ptr) +{ + queue_work(ap_work_queue, &ap_config_work); + ap_config_timer.expires = jiffies + ap_config_time * HZ; + add_timer(&ap_config_timer); +} + +/** + * Set up the timer to run the poll tasklet + */ +static inline void ap_schedule_poll_timer(void) +{ + if (timer_pending(&ap_poll_timer)) + return; + mod_timer(&ap_poll_timer, jiffies + AP_POLL_TIME); +} + +/** + * Receive pending reply messages from an AP device. + * @ap_dev: pointer to the AP device + * @flags: pointer to control flags, bit 2^0 is set if another poll is + * required, bit 2^1 is set if the poll timer needs to get armed + * Returns 0 if the device is still present, -ENODEV if not. + */ +static inline int ap_poll_read(struct ap_device *ap_dev, unsigned long *flags) +{ + struct ap_queue_status status; + struct ap_message *ap_msg; + + if (ap_dev->queue_count <= 0) + return 0; + status = __ap_recv(ap_dev->qid, &ap_dev->reply->psmid, + ap_dev->reply->message, ap_dev->reply->length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + atomic_dec(&ap_poll_requests); + ap_dev->queue_count--; + list_for_each_entry(ap_msg, &ap_dev->pendingq, list) { + if (ap_msg->psmid != ap_dev->reply->psmid) + continue; + list_del_init(&ap_msg->list); + ap_dev->pendingq_count--; + ap_dev->drv->receive(ap_dev, ap_msg, ap_dev->reply); + break; + } + if (ap_dev->queue_count > 0) + *flags |= 1; + break; + case AP_RESPONSE_NO_PENDING_REPLY: + if (status.queue_empty) { + /* The card shouldn't forget requests but who knows. */ + ap_dev->queue_count = 0; + list_splice_init(&ap_dev->pendingq, &ap_dev->requestq); + ap_dev->requestq_count += ap_dev->pendingq_count; + ap_dev->pendingq_count = 0; + } else + *flags |= 2; + break; + default: + return -ENODEV; + } + return 0; +} + +/** + * Send messages from the request queue to an AP device. + * @ap_dev: pointer to the AP device + * @flags: pointer to control flags, bit 2^0 is set if another poll is + * required, bit 2^1 is set if the poll timer needs to get armed + * Returns 0 if the device is still present, -ENODEV if not. + */ +static inline int ap_poll_write(struct ap_device *ap_dev, unsigned long *flags) +{ + struct ap_queue_status status; + struct ap_message *ap_msg; + + if (ap_dev->requestq_count <= 0 || + ap_dev->queue_count >= ap_dev->queue_depth) + return 0; + /* Start the next request on the queue. */ + ap_msg = list_entry(ap_dev->requestq.next, struct ap_message, list); + status = __ap_send(ap_dev->qid, ap_msg->psmid, + ap_msg->message, ap_msg->length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + atomic_inc(&ap_poll_requests); + ap_dev->queue_count++; + list_move_tail(&ap_msg->list, &ap_dev->pendingq); + ap_dev->requestq_count--; + ap_dev->pendingq_count++; + if (ap_dev->queue_count < ap_dev->queue_depth && + ap_dev->requestq_count > 0) + *flags |= 1; + *flags |= 2; + break; + case AP_RESPONSE_Q_FULL: + *flags |= 2; + break; + case AP_RESPONSE_MESSAGE_TOO_BIG: + return -EINVAL; + default: + return -ENODEV; + } + return 0; +} + +/** + * Poll AP device for pending replies and send new messages. If either + * ap_poll_read or ap_poll_write returns -ENODEV unregister the device. + * @ap_dev: pointer to the bus device + * @flags: pointer to control flags, bit 2^0 is set if another poll is + * required, bit 2^1 is set if the poll timer needs to get armed + * Returns 0. + */ +static inline int ap_poll_queue(struct ap_device *ap_dev, unsigned long *flags) +{ + int rc; + + rc = ap_poll_read(ap_dev, flags); + if (rc) + return rc; + return ap_poll_write(ap_dev, flags); +} + +/** + * Queue a message to a device. + * @ap_dev: pointer to the AP device + * @ap_msg: the message to be queued + */ +static int __ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) +{ + struct ap_queue_status status; + + if (list_empty(&ap_dev->requestq) && + ap_dev->queue_count < ap_dev->queue_depth) { + status = __ap_send(ap_dev->qid, ap_msg->psmid, + ap_msg->message, ap_msg->length); + switch (status.response_code) { + case AP_RESPONSE_NORMAL: + list_add_tail(&ap_msg->list, &ap_dev->pendingq); + atomic_inc(&ap_poll_requests); + ap_dev->pendingq_count++; + ap_dev->queue_count++; + ap_dev->total_request_count++; + break; + case AP_RESPONSE_Q_FULL: + list_add_tail(&ap_msg->list, &ap_dev->requestq); + ap_dev->requestq_count++; + ap_dev->total_request_count++; + return -EBUSY; + case AP_RESPONSE_MESSAGE_TOO_BIG: + ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-EINVAL)); + return -EINVAL; + default: /* Device is gone. */ + ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV)); + return -ENODEV; + } + } else { + list_add_tail(&ap_msg->list, &ap_dev->requestq); + ap_dev->requestq_count++; + ap_dev->total_request_count++; + return -EBUSY; + } + ap_schedule_poll_timer(); + return 0; +} + +void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) +{ + unsigned long flags; + int rc; + + spin_lock_bh(&ap_dev->lock); + if (!ap_dev->unregistered) { + /* Make room on the queue by polling for finished requests. */ + rc = ap_poll_queue(ap_dev, &flags); + if (!rc) + rc = __ap_queue_message(ap_dev, ap_msg); + if (!rc) + wake_up(&ap_poll_wait); + } else { + ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV)); + rc = 0; + } + spin_unlock_bh(&ap_dev->lock); + if (rc == -ENODEV) + device_unregister(&ap_dev->device); +} +EXPORT_SYMBOL(ap_queue_message); + +/** + * Cancel a crypto request. This is done by removing the request + * from the devive pendingq or requestq queue. Note that the + * request stays on the AP queue. When it finishes the message + * reply will be discarded because the psmid can't be found. + * @ap_dev: AP device that has the message queued + * @ap_msg: the message that is to be removed + */ +void ap_cancel_message(struct ap_device *ap_dev, struct ap_message *ap_msg) +{ + struct ap_message *tmp; + + spin_lock_bh(&ap_dev->lock); + if (!list_empty(&ap_msg->list)) { + list_for_each_entry(tmp, &ap_dev->pendingq, list) + if (tmp->psmid == ap_msg->psmid) { + ap_dev->pendingq_count--; + goto found; + } + ap_dev->requestq_count--; + found: + list_del_init(&ap_msg->list); + } + spin_unlock_bh(&ap_dev->lock); +} +EXPORT_SYMBOL(ap_cancel_message); + +/** + * AP receive polling for finished AP requests + */ +static void ap_poll_timeout(unsigned long unused) +{ + tasklet_schedule(&ap_tasklet); +} + +/** + * Poll all AP devices on the bus in a round robin fashion. Continue + * polling until bit 2^0 of the control flags is not set. If bit 2^1 + * of the control flags has been set arm the poll timer. + */ +static int __ap_poll_all(struct device *dev, void *data) +{ + struct ap_device *ap_dev = to_ap_dev(dev); + int rc; + + spin_lock(&ap_dev->lock); + if (!ap_dev->unregistered) { + rc = ap_poll_queue(to_ap_dev(dev), (unsigned long *) data); + } else + rc = 0; + spin_unlock(&ap_dev->lock); + if (rc) + device_unregister(&ap_dev->device); + return 0; +} + +static void ap_poll_all(unsigned long dummy) +{ + unsigned long flags; + + do { + flags = 0; + bus_for_each_dev(&ap_bus_type, NULL, &flags, __ap_poll_all); + } while (flags & 1); + if (flags & 2) + ap_schedule_poll_timer(); +} + +/** + * AP bus poll thread. The purpose of this thread is to poll for + * finished requests in a loop if there is a "free" cpu - that is + * a cpu that doesn't have anything better to do. The polling stops + * as soon as there is another task or if all messages have been + * delivered. + */ +static int ap_poll_thread(void *data) +{ + DECLARE_WAITQUEUE(wait, current); + unsigned long flags; + int requests; + + set_user_nice(current, -20); + while (1) { + if (need_resched()) { + schedule(); + continue; + } + add_wait_queue(&ap_poll_wait, &wait); + set_current_state(TASK_INTERRUPTIBLE); + if (kthread_should_stop()) + break; + requests = atomic_read(&ap_poll_requests); + if (requests <= 0) + schedule(); + set_current_state(TASK_RUNNING); + remove_wait_queue(&ap_poll_wait, &wait); + + local_bh_disable(); + flags = 0; + bus_for_each_dev(&ap_bus_type, NULL, &flags, __ap_poll_all); + local_bh_enable(); + } + set_current_state(TASK_RUNNING); + remove_wait_queue(&ap_poll_wait, &wait); + return 0; +} + +static int ap_poll_thread_start(void) +{ + int rc; + + mutex_lock(&ap_poll_thread_mutex); + if (!ap_poll_kthread) { + ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll"); + rc = IS_ERR(ap_poll_kthread) ? PTR_ERR(ap_poll_kthread) : 0; + if (rc) + ap_poll_kthread = NULL; + } + else + rc = 0; + mutex_unlock(&ap_poll_thread_mutex); + return rc; +} + +static void ap_poll_thread_stop(void) +{ + mutex_lock(&ap_poll_thread_mutex); + if (ap_poll_kthread) { + kthread_stop(ap_poll_kthread); + ap_poll_kthread = NULL; + } + mutex_unlock(&ap_poll_thread_mutex); +} + +/** + * The module initialization code. + */ +int __init ap_module_init(void) +{ + int rc, i; + + if (ap_domain_index < -1 || ap_domain_index >= AP_DOMAINS) { + printk(KERN_WARNING "Invalid param: domain = %d. " + " Not loading.\n", ap_domain_index); + return -EINVAL; + } + if (ap_instructions_available() != 0) { + printk(KERN_WARNING "AP instructions not installed.\n"); + return -ENODEV; + } + + /* Create /sys/bus/ap. */ + rc = bus_register(&ap_bus_type); + if (rc) + goto out; + for (i = 0; ap_bus_attrs[i]; i++) { + rc = bus_create_file(&ap_bus_type, ap_bus_attrs[i]); + if (rc) + goto out_bus; + } + + /* Create /sys/devices/ap. */ + ap_root_device = s390_root_dev_register("ap"); + rc = IS_ERR(ap_root_device) ? PTR_ERR(ap_root_device) : 0; + if (rc) + goto out_bus; + + ap_work_queue = create_singlethread_workqueue("kapwork"); + if (!ap_work_queue) { + rc = -ENOMEM; + goto out_root; + } + + if (ap_select_domain() == 0) + ap_scan_bus(NULL); + + /* Setup the ap bus rescan timer. */ + init_timer(&ap_config_timer); + ap_config_timer.function = ap_config_timeout; + ap_config_timer.data = 0; + ap_config_timer.expires = jiffies + ap_config_time * HZ; + add_timer(&ap_config_timer); + + /* Start the low priority AP bus poll thread. */ + if (ap_thread_flag) { + rc = ap_poll_thread_start(); + if (rc) + goto out_work; + } + + return 0; + +out_work: + del_timer_sync(&ap_config_timer); + del_timer_sync(&ap_poll_timer); + destroy_workqueue(ap_work_queue); +out_root: + s390_root_dev_unregister(ap_root_device); +out_bus: + while (i--) + bus_remove_file(&ap_bus_type, ap_bus_attrs[i]); + bus_unregister(&ap_bus_type); +out: + return rc; +} + +static int __ap_match_all(struct device *dev, void *data) +{ + return 1; +} + +/** + * The module termination code + */ +void ap_module_exit(void) +{ + int i; + struct device *dev; + + ap_poll_thread_stop(); + del_timer_sync(&ap_config_timer); + del_timer_sync(&ap_poll_timer); + destroy_workqueue(ap_work_queue); + s390_root_dev_unregister(ap_root_device); + while ((dev = bus_find_device(&ap_bus_type, NULL, NULL, + __ap_match_all))) + { + device_unregister(dev); + put_device(dev); + } + for (i = 0; ap_bus_attrs[i]; i++) + bus_remove_file(&ap_bus_type, ap_bus_attrs[i]); + bus_unregister(&ap_bus_type); +} + +#ifndef CONFIG_ZCRYPT_MONOLITHIC +module_init(ap_module_init); +module_exit(ap_module_exit); +#endif |