xref: /linux/drivers/s390/crypto/zcrypt_api.h (revision 4b99990cdf9560e8a071640baf19f312e6ae02f4)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  *  Copyright IBM Corp. 2001, 2019
4  *  Author(s): Robert Burroughs
5  *	       Eric Rossman (edrossma@us.ibm.com)
6  *	       Cornelia Huck <cornelia.huck@de.ibm.com>
7  *
8  *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
9  *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
10  *				  Ralph Wuerthner <rwuerthn@de.ibm.com>
11  *  MSGTYPE restruct:		  Holger Dengler <hd@linux.vnet.ibm.com>
12  */
13 
14 #ifndef _ZCRYPT_API_H_
15 #define _ZCRYPT_API_H_
16 
17 #include <linux/atomic.h>
18 #include <asm/debug.h>
19 #include <asm/zcrypt.h>
20 #include "ap_bus.h"
21 
22 /**
23  * Supported device types
24  */
25 #define ZCRYPT_CEX2C		5
26 #define ZCRYPT_CEX2A		6
27 #define ZCRYPT_CEX3C		7
28 #define ZCRYPT_CEX3A		8
29 #define ZCRYPT_CEX4	       10
30 #define ZCRYPT_CEX5	       11
31 #define ZCRYPT_CEX6	       12
32 #define ZCRYPT_CEX7	       13
33 
34 /**
35  * Large random numbers are pulled in 4096 byte chunks from the crypto cards
36  * and stored in a page. Be careful when increasing this buffer due to size
37  * limitations for AP requests.
38  */
39 #define ZCRYPT_RNG_BUFFER_SIZE	4096
40 
41 /**
42  * The zcrypt_wait_api_operational() function waits this
43  * amount in milliseconds for ap_wait_aqpn_bindings_complete().
44  * Also on a cprb send failure with ENODEV the send functions
45  * trigger an ap bus rescan and wait this time in milliseconds
46  * for ap_wait_aqpn_bindings_complete() before resending.
47  */
48 #define ZCRYPT_WAIT_BINDINGS_COMPLETE_MS 30000
49 
50 /*
51  * Identifier for Crypto Request Performance Index
52  */
53 enum crypto_ops {
54 	MEX_1K,
55 	MEX_2K,
56 	MEX_4K,
57 	CRT_1K,
58 	CRT_2K,
59 	CRT_4K,
60 	HWRNG,
61 	SECKEY,
62 	NUM_OPS
63 };
64 
65 struct zcrypt_queue;
66 
67 /* struct to hold tracking information for a userspace request/response */
68 struct zcrypt_track {
69 	int again_counter;		/* retry attempts counter */
70 	int last_qid;			/* last qid used */
71 	int last_rc;			/* last return code */
72 };
73 
74 /* defines related to message tracking */
75 #define TRACK_AGAIN_MAX 10
76 #define TRACK_AGAIN_CARD_WEIGHT_PENALTY  1000
77 #define TRACK_AGAIN_QUEUE_WEIGHT_PENALTY 10000
78 
79 /*
80  * xflags - to be used with zcrypt_send_cprb() and
81  * zcrypt_send_ep11_cprb() for the xflags parameter.
82  */
83 #define ZCRYPT_XFLAG_USERSPACE	0x0001	/* data ptrs address userspace */
84 #define ZCRYPT_XFLAG_NOMEMALLOC 0x0002	/* do not allocate memory via kmalloc */
85 
86 struct zcrypt_ops {
87 	long (*rsa_modexpo)(struct zcrypt_queue *, struct ica_rsa_modexpo *,
88 			    struct ap_message *);
89 	long (*rsa_modexpo_crt)(struct zcrypt_queue *,
90 				struct ica_rsa_modexpo_crt *,
91 				struct ap_message *);
92 	long (*send_cprb)(bool userspace, struct zcrypt_queue *, struct ica_xcRB *,
93 			  struct ap_message *);
94 	long (*send_ep11_cprb)(bool userspace, struct zcrypt_queue *, struct ep11_urb *,
95 			       struct ap_message *);
96 	long (*rng)(struct zcrypt_queue *, char *, struct ap_message *);
97 	struct list_head list;		/* zcrypt ops list. */
98 	struct module *owner;
99 	int variant;
100 	char name[128];
101 };
102 
103 struct zcrypt_card {
104 	struct list_head list;		/* Device list. */
105 	struct list_head zqueues;	/* List of zcrypt queues */
106 	struct kref refcount;		/* device refcounting */
107 	int online;			/* User online/offline */
108 	struct ap_card *card;		/* The "real" ap card device. */
109 	char *type_string;		/* User space device name. */
110 	int user_space_type;		/* User space device id. */
111 	int min_mod_size;		/* Min number of bits. */
112 	int max_mod_size;		/* Max number of bits. */
113 	int max_exp_bit_length;
114 	const int *speed_rating;	/* Speed idx of crypto ops. */
115 	atomic_t load;			/* Utilization of the crypto device */
116 	int request_count;		/* # current requests. */
117 };
118 
119 struct zcrypt_queue {
120 	struct list_head list;		/* Device list. */
121 	struct kref refcount;		/* device refcounting */
122 	int online;			/* User online/offline */
123 	struct zcrypt_card *zcard;
124 	struct zcrypt_ops *ops;		/* Crypto operations. */
125 	struct ap_queue *queue;		/* The "real" ap queue device. */
126 	struct ap_message reply;	/* Per-device reply structure. */
127 	atomic_t load;			/* Utilization of the crypto device */
128 	int request_count;		/* # current requests. */
129 };
130 
131 /* transport layer rescanning */
132 extern atomic_t zcrypt_rescan_req;
133 
134 extern spinlock_t zcrypt_list_lock;
135 extern struct list_head zcrypt_card_list;
136 
137 extern unsigned int zcrypt_mempool_threshold;
138 
139 #define for_each_zcrypt_card(_zc) \
140 	list_for_each_entry(_zc, &zcrypt_card_list, list)
141 
142 #define for_each_zcrypt_queue(_zq, _zc) \
143 	list_for_each_entry(_zq, &(_zc)->zqueues, list)
144 
145 struct zcrypt_card *zcrypt_card_alloc(void);
146 void zcrypt_card_free(struct zcrypt_card *);
147 void zcrypt_card_get(struct zcrypt_card *);
148 int zcrypt_card_put(struct zcrypt_card *);
149 int zcrypt_card_register(struct zcrypt_card *);
150 void zcrypt_card_unregister(struct zcrypt_card *);
151 
152 struct zcrypt_queue *zcrypt_queue_alloc(size_t);
153 void zcrypt_queue_free(struct zcrypt_queue *);
154 void zcrypt_queue_get(struct zcrypt_queue *);
155 int zcrypt_queue_put(struct zcrypt_queue *);
156 int zcrypt_queue_register(struct zcrypt_queue *);
157 void zcrypt_queue_unregister(struct zcrypt_queue *);
158 bool zcrypt_queue_force_online(struct zcrypt_queue *zq, int online);
159 
160 int zcrypt_rng_device_add(void);
161 void zcrypt_rng_device_remove(void);
162 
163 void zcrypt_msgtype_register(struct zcrypt_ops *);
164 void zcrypt_msgtype_unregister(struct zcrypt_ops *);
165 struct zcrypt_ops *zcrypt_msgtype(unsigned char *, int);
166 int zcrypt_api_init(void);
167 void zcrypt_api_exit(void);
168 long zcrypt_send_cprb(struct ica_xcRB *xcRB, u32 xflags);
169 long zcrypt_send_ep11_cprb(struct ep11_urb *urb, u32 xflags);
170 void zcrypt_device_status_mask_ext(struct zcrypt_device_status_ext *devstatus,
171 				   int maxcard, int maxqueue);
172 int zcrypt_device_status_ext(int card, int queue,
173 			     struct zcrypt_device_status_ext *devstatus);
174 
175 int zcrypt_wait_api_operational(void);
176 
177 static inline unsigned long z_copy_from_user(bool userspace,
178 					     void *to,
179 					     const void __user *from,
180 					     unsigned long n)
181 {
182 	if (likely(userspace))
183 		return copy_from_user(to, from, n);
184 	memcpy(to, (void __force *)from, n);
185 	return 0;
186 }
187 
188 static inline unsigned long z_copy_to_user(bool userspace,
189 					   void __user *to,
190 					   const void *from,
191 					   unsigned long n)
192 {
193 	if (likely(userspace))
194 		return copy_to_user(to, from, n);
195 	memcpy((void __force *)to, from, n);
196 	return 0;
197 }
198 
199 #endif /* _ZCRYPT_API_H_ */
200