1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * VMware VMCI driver (vmciContext.h)
4  *
5  * Copyright (C) 2012 VMware, Inc. All rights reserved.
6  */
7 
8 #ifndef _VMCI_CONTEXT_H_
9 #define _VMCI_CONTEXT_H_
10 
11 #include <linux/vmw_vmci_defs.h>
12 #include <linux/atomic.h>
13 #include <linux/kref.h>
14 #include <linux/types.h>
15 #include <linux/wait.h>
16 
17 #include "vmci_handle_array.h"
18 #include "vmci_datagram.h"
19 
20 /* Used to determine what checkpoint state to get and set. */
21 enum {
22 	VMCI_NOTIFICATION_CPT_STATE = 1,
23 	VMCI_WELLKNOWN_CPT_STATE    = 2,
24 	VMCI_DG_OUT_STATE           = 3,
25 	VMCI_DG_IN_STATE            = 4,
26 	VMCI_DG_IN_SIZE_STATE       = 5,
27 	VMCI_DOORBELL_CPT_STATE     = 6,
28 };
29 
30 /* Host specific struct used for signalling */
31 struct vmci_host {
32 	wait_queue_head_t wait_queue;
33 };
34 
35 struct vmci_handle_list {
36 	struct list_head node;
37 	struct vmci_handle handle;
38 };
39 
40 struct vmci_ctx {
41 	struct list_head list_item;       /* For global VMCI list. */
42 	u32 cid;
43 	struct kref kref;
44 	struct list_head datagram_queue;  /* Head of per VM queue. */
45 	u32 pending_datagrams;
46 	size_t datagram_queue_size;	  /* Size of datagram queue in bytes. */
47 
48 	/*
49 	 * Version of the code that created
50 	 * this context; e.g., VMX.
51 	 */
52 	int user_version;
53 	spinlock_t lock;  /* Locks callQueue and handle_arrays. */
54 
55 	/*
56 	 * queue_pairs attached to.  The array of
57 	 * handles for queue pairs is accessed
58 	 * from the code for QP API, and there
59 	 * it is protected by the QP lock.  It
60 	 * is also accessed from the context
61 	 * clean up path, which does not
62 	 * require a lock.  VMCILock is not
63 	 * used to protect the QP array field.
64 	 */
65 	struct vmci_handle_arr *queue_pair_array;
66 
67 	/* Doorbells created by context. */
68 	struct vmci_handle_arr *doorbell_array;
69 
70 	/* Doorbells pending for context. */
71 	struct vmci_handle_arr *pending_doorbell_array;
72 
73 	/* Contexts current context is subscribing to. */
74 	struct list_head notifier_list;
75 	unsigned int n_notifiers;
76 
77 	struct vmci_host host_context;
78 	u32 priv_flags;
79 
80 	const struct cred *cred;
81 	bool *notify;		/* Notify flag pointer - hosted only. */
82 	struct page *notify_page;	/* Page backing the notify UVA. */
83 };
84 
85 /* VMCINotifyAddRemoveInfo: Used to add/remove remote context notifications. */
86 struct vmci_ctx_info {
87 	u32 remote_cid;
88 	int result;
89 };
90 
91 /* VMCICptBufInfo: Used to set/get current context's checkpoint state. */
92 struct vmci_ctx_chkpt_buf_info {
93 	u64 cpt_buf;
94 	u32 cpt_type;
95 	u32 buf_size;
96 	s32 result;
97 	u32 _pad;
98 };
99 
100 /*
101  * VMCINotificationReceiveInfo: Used to recieve pending notifications
102  * for doorbells and queue pairs.
103  */
104 struct vmci_ctx_notify_recv_info {
105 	u64 db_handle_buf_uva;
106 	u64 db_handle_buf_size;
107 	u64 qp_handle_buf_uva;
108 	u64 qp_handle_buf_size;
109 	s32 result;
110 	u32 _pad;
111 };
112 
113 /*
114  * Utilility function that checks whether two entities are allowed
115  * to interact. If one of them is restricted, the other one must
116  * be trusted.
117  */
118 static inline bool vmci_deny_interaction(u32 part_one, u32 part_two)
119 {
120 	return ((part_one & VMCI_PRIVILEGE_FLAG_RESTRICTED) &&
121 		!(part_two & VMCI_PRIVILEGE_FLAG_TRUSTED)) ||
122 	       ((part_two & VMCI_PRIVILEGE_FLAG_RESTRICTED) &&
123 		!(part_one & VMCI_PRIVILEGE_FLAG_TRUSTED));
124 }
125 
126 struct vmci_ctx *vmci_ctx_create(u32 cid, u32 flags,
127 				 uintptr_t event_hnd, int version,
128 				 const struct cred *cred);
129 void vmci_ctx_destroy(struct vmci_ctx *context);
130 
131 bool vmci_ctx_supports_host_qp(struct vmci_ctx *context);
132 int vmci_ctx_enqueue_datagram(u32 cid, struct vmci_datagram *dg);
133 int vmci_ctx_dequeue_datagram(struct vmci_ctx *context,
134 			      size_t *max_size, struct vmci_datagram **dg);
135 int vmci_ctx_pending_datagrams(u32 cid, u32 *pending);
136 struct vmci_ctx *vmci_ctx_get(u32 cid);
137 void vmci_ctx_put(struct vmci_ctx *context);
138 bool vmci_ctx_exists(u32 cid);
139 
140 int vmci_ctx_add_notification(u32 context_id, u32 remote_cid);
141 int vmci_ctx_remove_notification(u32 context_id, u32 remote_cid);
142 int vmci_ctx_get_chkpt_state(u32 context_id, u32 cpt_type,
143 			     u32 *num_cids, void **cpt_buf_ptr);
144 int vmci_ctx_set_chkpt_state(u32 context_id, u32 cpt_type,
145 			     u32 num_cids, void *cpt_buf);
146 
147 int vmci_ctx_qp_create(struct vmci_ctx *context, struct vmci_handle handle);
148 int vmci_ctx_qp_destroy(struct vmci_ctx *context, struct vmci_handle handle);
149 bool vmci_ctx_qp_exists(struct vmci_ctx *context, struct vmci_handle handle);
150 
151 void vmci_ctx_check_signal_notify(struct vmci_ctx *context);
152 void vmci_ctx_unset_notify(struct vmci_ctx *context);
153 
154 int vmci_ctx_dbell_create(u32 context_id, struct vmci_handle handle);
155 int vmci_ctx_dbell_destroy(u32 context_id, struct vmci_handle handle);
156 int vmci_ctx_dbell_destroy_all(u32 context_id);
157 int vmci_ctx_notify_dbell(u32 cid, struct vmci_handle handle,
158 			  u32 src_priv_flags);
159 
160 int vmci_ctx_rcv_notifications_get(u32 context_id, struct vmci_handle_arr
161 				   **db_handle_array, struct vmci_handle_arr
162 				   **qp_handle_array);
163 void vmci_ctx_rcv_notifications_release(u32 context_id, struct vmci_handle_arr
164 					*db_handle_array, struct vmci_handle_arr
165 					*qp_handle_array, bool success);
166 
167 static inline u32 vmci_ctx_get_id(struct vmci_ctx *context)
168 {
169 	if (!context)
170 		return VMCI_INVALID_ID;
171 	return context->cid;
172 }
173 
174 #endif /* _VMCI_CONTEXT_H_ */
175