linux/drivers/s390/crypto/ap_bus.h
Harald Freudenberger 104f708fd1 s390/zcrypt: reinit ap queue state machine during device probe
Until the vfio-ap driver came into live there was a well known
agreement about the way how ap devices are initialized and their
states when the driver's probe function is called.

However, the vfio device driver when receiving an ap queue device does
additional resets thereby removing the registration for interrupts for
the ap device done by the ap bus core code. So when later the vfio
driver releases the device and one of the default zcrypt drivers takes
care of the device the interrupt registration needs to get
renewed. The current code does no renew and result is that requests
send into such a queue will never see a reply processed - the
application hangs.

This patch adds a function which resets the aq queue state machine for
the ap queue device and triggers the walk through the initial states
(which are reset and registration for interrupts). This function is
now called before the driver's probe function is invoked.

When the association between driver and device is released, the
driver's remove function is called. The current implementation calls a
ap queue function ap_queue_remove(). This invokation has been moved to
the ap bus function to make the probe / remove pair for ap bus and
drivers more symmetric.

Fixes: 7e0bdbe5c2 ("s390/zcrypt: AP bus support for alternate driver(s)")
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewd-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewd-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-11-27 10:43:35 +01:00

310 lines
9.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright IBM Corp. 2006, 2012
* Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Ralph Wuerthner <rwuerthn@de.ibm.com>
* Felix Beck <felix.beck@de.ibm.com>
* Holger Dengler <hd@linux.vnet.ibm.com>
*
* Adjunct processor bus header file.
*/
#ifndef _AP_BUS_H_
#define _AP_BUS_H_
#include <linux/device.h>
#include <linux/types.h>
#include <asm/isc.h>
#include <asm/ap.h>
#define AP_DEVICES 256 /* Number of AP devices. */
#define AP_DOMAINS 256 /* Number of AP domains. */
#define AP_IOCTLS 256 /* Number of ioctls. */
#define AP_RESET_TIMEOUT (HZ*0.7) /* Time in ticks for reset timeouts. */
#define AP_CONFIG_TIME 30 /* Time in seconds between AP bus rescans. */
#define AP_POLL_TIME 1 /* Time in ticks between receive polls. */
extern int ap_domain_index;
extern spinlock_t ap_list_lock;
extern struct list_head ap_card_list;
static inline int ap_test_bit(unsigned int *ptr, unsigned int nr)
{
return (*ptr & (0x80000000u >> nr)) != 0;
}
#define AP_RESPONSE_NORMAL 0x00
#define AP_RESPONSE_Q_NOT_AVAIL 0x01
#define AP_RESPONSE_RESET_IN_PROGRESS 0x02
#define AP_RESPONSE_DECONFIGURED 0x03
#define AP_RESPONSE_CHECKSTOPPED 0x04
#define AP_RESPONSE_BUSY 0x05
#define AP_RESPONSE_INVALID_ADDRESS 0x06
#define AP_RESPONSE_OTHERWISE_CHANGED 0x07
#define AP_RESPONSE_Q_FULL 0x10
#define AP_RESPONSE_NO_PENDING_REPLY 0x10
#define AP_RESPONSE_INDEX_TOO_BIG 0x11
#define AP_RESPONSE_NO_FIRST_PART 0x13
#define AP_RESPONSE_MESSAGE_TOO_BIG 0x15
#define AP_RESPONSE_REQ_FAC_NOT_INST 0x16
/*
* Known device types
*/
#define AP_DEVICE_TYPE_PCICC 3
#define AP_DEVICE_TYPE_PCICA 4
#define AP_DEVICE_TYPE_PCIXCC 5
#define AP_DEVICE_TYPE_CEX2A 6
#define AP_DEVICE_TYPE_CEX2C 7
#define AP_DEVICE_TYPE_CEX3A 8
#define AP_DEVICE_TYPE_CEX3C 9
#define AP_DEVICE_TYPE_CEX4 10
#define AP_DEVICE_TYPE_CEX5 11
#define AP_DEVICE_TYPE_CEX6 12
/*
* Known function facilities
*/
#define AP_FUNC_MEX4K 1
#define AP_FUNC_CRT4K 2
#define AP_FUNC_COPRO 3
#define AP_FUNC_ACCEL 4
#define AP_FUNC_EP11 5
#define AP_FUNC_APXA 6
/*
* AP interrupt states
*/
#define AP_INTR_DISABLED 0 /* AP interrupt disabled */
#define AP_INTR_ENABLED 1 /* AP interrupt enabled */
/*
* AP device states
*/
enum ap_state {
AP_STATE_RESET_START,
AP_STATE_RESET_WAIT,
AP_STATE_SETIRQ_WAIT,
AP_STATE_IDLE,
AP_STATE_WORKING,
AP_STATE_QUEUE_FULL,
AP_STATE_SUSPEND_WAIT,
AP_STATE_BORKED,
NR_AP_STATES
};
/*
* AP device events
*/
enum ap_event {
AP_EVENT_POLL,
AP_EVENT_TIMEOUT,
NR_AP_EVENTS
};
/*
* AP wait behaviour
*/
enum ap_wait {
AP_WAIT_AGAIN, /* retry immediately */
AP_WAIT_TIMEOUT, /* wait for timeout */
AP_WAIT_INTERRUPT, /* wait for thin interrupt (if available) */
AP_WAIT_NONE, /* no wait */
NR_AP_WAIT
};
struct ap_device;
struct ap_message;
/*
* The ap driver struct includes a flags field which holds some info for
* the ap bus about the driver. Currently only one flag is supported and
* used: The DEFAULT flag marks an ap driver as a default driver which is
* used together with the apmask and aqmask whitelisting of the ap bus.
*/
#define AP_DRIVER_FLAG_DEFAULT 0x0001
struct ap_driver {
struct device_driver driver;
struct ap_device_id *ids;
unsigned int flags;
int (*probe)(struct ap_device *);
void (*remove)(struct ap_device *);
void (*suspend)(struct ap_device *);
void (*resume)(struct ap_device *);
};
#define to_ap_drv(x) container_of((x), struct ap_driver, driver)
int ap_driver_register(struct ap_driver *, struct module *, char *);
void ap_driver_unregister(struct ap_driver *);
struct ap_device {
struct device device;
struct ap_driver *drv; /* Pointer to AP device driver. */
int device_type; /* AP device type. */
};
#define to_ap_dev(x) container_of((x), struct ap_device, device)
struct ap_card {
struct ap_device ap_dev;
struct list_head list; /* Private list of AP cards. */
struct list_head queues; /* List of assoc. AP queues */
void *private; /* ap driver private pointer. */
int raw_hwtype; /* AP raw hardware type. */
unsigned int functions; /* AP device function bitfield. */
int queue_depth; /* AP queue depth.*/
int id; /* AP card number. */
atomic_t total_request_count; /* # requests ever for this AP device.*/
};
#define to_ap_card(x) container_of((x), struct ap_card, ap_dev.device)
struct ap_queue {
struct ap_device ap_dev;
struct list_head list; /* Private list of AP queues. */
struct ap_card *card; /* Ptr to assoc. AP card. */
spinlock_t lock; /* Per device lock. */
void *private; /* ap driver private pointer. */
ap_qid_t qid; /* AP queue id. */
int interrupt; /* indicate if interrupts are enabled */
int queue_count; /* # messages currently on AP queue. */
enum ap_state state; /* State of the AP device. */
int pendingq_count; /* # requests on pendingq list. */
int requestq_count; /* # requests on requestq list. */
int total_request_count; /* # requests ever for this AP device.*/
int request_timeout; /* Request timeout in jiffies. */
struct timer_list timeout; /* Timer for request timeouts. */
struct list_head pendingq; /* List of message sent to AP queue. */
struct list_head requestq; /* List of message yet to be sent. */
struct ap_message *reply; /* Per device reply message. */
};
#define to_ap_queue(x) container_of((x), struct ap_queue, ap_dev.device)
typedef enum ap_wait (ap_func_t)(struct ap_queue *queue);
struct ap_message {
struct list_head list; /* Request queueing. */
unsigned long long psmid; /* Message id. */
void *message; /* Pointer to message buffer. */
size_t length; /* Message length. */
int rc; /* Return code for this message */
void *private; /* ap driver private pointer. */
unsigned int special:1; /* Used for special commands. */
/* receive is called from tasklet context */
void (*receive)(struct ap_queue *, struct ap_message *,
struct ap_message *);
};
/**
* ap_init_message() - Initialize ap_message.
* Initialize a message before using. Otherwise this might result in
* unexpected behaviour.
*/
static inline void ap_init_message(struct ap_message *ap_msg)
{
memset(ap_msg, 0, sizeof(*ap_msg));
}
/**
* ap_release_message() - Release ap_message.
* Releases all memory used internal within the ap_message struct
* Currently this is the message and private field.
*/
static inline void ap_release_message(struct ap_message *ap_msg)
{
kzfree(ap_msg->message);
kzfree(ap_msg->private);
}
#define for_each_ap_card(_ac) \
list_for_each_entry(_ac, &ap_card_list, list)
#define for_each_ap_queue(_aq, _ac) \
list_for_each_entry(_aq, &(_ac)->queues, list)
/*
* Note: don't use ap_send/ap_recv after using ap_queue_message
* for the first time. Otherwise the ap message queue will get
* confused.
*/
int ap_send(ap_qid_t, unsigned long long, void *, size_t);
int ap_recv(ap_qid_t, unsigned long long *, void *, size_t);
enum ap_wait ap_sm_event(struct ap_queue *aq, enum ap_event event);
enum ap_wait ap_sm_event_loop(struct ap_queue *aq, enum ap_event event);
void ap_queue_message(struct ap_queue *aq, struct ap_message *ap_msg);
void ap_cancel_message(struct ap_queue *aq, struct ap_message *ap_msg);
void ap_flush_queue(struct ap_queue *aq);
void *ap_airq_ptr(void);
void ap_wait(enum ap_wait wait);
void ap_request_timeout(struct timer_list *t);
void ap_bus_force_rescan(void);
void ap_queue_init_reply(struct ap_queue *aq, struct ap_message *ap_msg);
struct ap_queue *ap_queue_create(ap_qid_t qid, int device_type);
void ap_queue_remove(struct ap_queue *aq);
void ap_queue_suspend(struct ap_device *ap_dev);
void ap_queue_resume(struct ap_device *ap_dev);
void ap_queue_reinit_state(struct ap_queue *aq);
struct ap_card *ap_card_create(int id, int queue_depth, int raw_device_type,
int comp_device_type, unsigned int functions);
struct ap_perms {
unsigned long ioctlm[BITS_TO_LONGS(AP_IOCTLS)];
unsigned long apm[BITS_TO_LONGS(AP_DEVICES)];
unsigned long aqm[BITS_TO_LONGS(AP_DOMAINS)];
};
extern struct ap_perms ap_perms;
extern struct mutex ap_perms_mutex;
/*
* check APQN for owned/reserved by ap bus and default driver(s).
* Checks if this APQN is or will be in use by the ap bus
* and the default set of drivers.
* If yes, returns 1, if not returns 0. On error a negative
* errno value is returned.
*/
int ap_owned_by_def_drv(int card, int queue);
/*
* check 'matrix' of APQNs for owned/reserved by ap bus and
* default driver(s).
* Checks if there is at least one APQN in the given 'matrix'
* marked as owned/reserved by the ap bus and default driver(s).
* If such an APQN is found the return value is 1, otherwise
* 0 is returned. On error a negative errno value is returned.
* The parameter apm is a bitmask which should be declared
* as DECLARE_BITMAP(apm, AP_DEVICES), the aqm parameter is
* similar, should be declared as DECLARE_BITMAP(aqm, AP_DOMAINS).
*/
int ap_apqn_in_matrix_owned_by_def_drv(unsigned long *apm,
unsigned long *aqm);
/*
* ap_parse_mask_str() - helper function to parse a bitmap string
* and clear/set the bits in the bitmap accordingly. The string may be
* given as absolute value, a hex string like 0x1F2E3D4C5B6A" simple
* overwriting the current content of the bitmap. Or as relative string
* like "+1-16,-32,-0x40,+128" where only single bits or ranges of
* bits are cleared or set. Distinction is done based on the very
* first character which may be '+' or '-' for the relative string
* and othewise assume to be an absolute value string. If parsing fails
* a negative errno value is returned. All arguments and bitmaps are
* big endian order.
*/
int ap_parse_mask_str(const char *str,
unsigned long *bitmap, int bits,
struct mutex *lock);
#endif /* _AP_BUS_H_ */