1/*
2 * VMware VMCI driver (vmciContext.h)
3 *
4 * Copyright (C) 2012 VMware, Inc. All rights reserved.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation version 2 and no later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
12 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * for more details.
14 */
15
16#ifndef _VMCI_CONTEXT_H_
17#define _VMCI_CONTEXT_H_
18
19#include <linux/vmw_vmci_defs.h>
20#include <linux/atomic.h>
21#include <linux/kref.h>
22#include <linux/types.h>
23#include <linux/wait.h>
24
25#include "vmci_handle_array.h"
26#include "vmci_datagram.h"
27
28/* Used to determine what checkpoint state to get and set. */
29enum {
30	VMCI_NOTIFICATION_CPT_STATE = 1,
31	VMCI_WELLKNOWN_CPT_STATE    = 2,
32	VMCI_DG_OUT_STATE           = 3,
33	VMCI_DG_IN_STATE            = 4,
34	VMCI_DG_IN_SIZE_STATE       = 5,
35	VMCI_DOORBELL_CPT_STATE     = 6,
36};
37
38/* Host specific struct used for signalling */
39struct vmci_host {
40	wait_queue_head_t wait_queue;
41};
42
43struct vmci_handle_list {
44	struct list_head node;
45	struct vmci_handle handle;
46};
47
48struct vmci_ctx {
49	struct list_head list_item;       /* For global VMCI list. */
50	u32 cid;
51	struct kref kref;
52	struct list_head datagram_queue;  /* Head of per VM queue. */
53	u32 pending_datagrams;
54	size_t datagram_queue_size;	  /* Size of datagram queue in bytes. */
55
56	/*
57	 * Version of the code that created
58	 * this context; e.g., VMX.
59	 */
60	int user_version;
61	spinlock_t lock;  /* Locks callQueue and handle_arrays. */
62
63	/*
64	 * queue_pairs attached to.  The array of
65	 * handles for queue pairs is accessed
66	 * from the code for QP API, and there
67	 * it is protected by the QP lock.  It
68	 * is also accessed from the context
69	 * clean up path, which does not
70	 * require a lock.  VMCILock is not
71	 * used to protect the QP array field.
72	 */
73	struct vmci_handle_arr *queue_pair_array;
74
75	/* Doorbells created by context. */
76	struct vmci_handle_arr *doorbell_array;
77
78	/* Doorbells pending for context. */
79	struct vmci_handle_arr *pending_doorbell_array;
80
81	/* Contexts current context is subscribing to. */
82	struct list_head notifier_list;
83	unsigned int n_notifiers;
84
85	struct vmci_host host_context;
86	u32 priv_flags;
87
88	const struct cred *cred;
89	bool *notify;		/* Notify flag pointer - hosted only. */
90	struct page *notify_page;	/* Page backing the notify UVA. */
91};
92
93/* VMCINotifyAddRemoveInfo: Used to add/remove remote context notifications. */
94struct vmci_ctx_info {
95	u32 remote_cid;
96	int result;
97};
98
99/* VMCICptBufInfo: Used to set/get current context's checkpoint state. */
100struct vmci_ctx_chkpt_buf_info {
101	u64 cpt_buf;
102	u32 cpt_type;
103	u32 buf_size;
104	s32 result;
105	u32 _pad;
106};
107
108/*
109 * VMCINotificationReceiveInfo: Used to recieve pending notifications
110 * for doorbells and queue pairs.
111 */
112struct vmci_ctx_notify_recv_info {
113	u64 db_handle_buf_uva;
114	u64 db_handle_buf_size;
115	u64 qp_handle_buf_uva;
116	u64 qp_handle_buf_size;
117	s32 result;
118	u32 _pad;
119};
120
121/*
122 * Utilility function that checks whether two entities are allowed
123 * to interact. If one of them is restricted, the other one must
124 * be trusted.
125 */
126static inline bool vmci_deny_interaction(u32 part_one, u32 part_two)
127{
128	return ((part_one & VMCI_PRIVILEGE_FLAG_RESTRICTED) &&
129		!(part_two & VMCI_PRIVILEGE_FLAG_TRUSTED)) ||
130	       ((part_two & VMCI_PRIVILEGE_FLAG_RESTRICTED) &&
131		!(part_one & VMCI_PRIVILEGE_FLAG_TRUSTED));
132}
133
134struct vmci_ctx *vmci_ctx_create(u32 cid, u32 flags,
135				 uintptr_t event_hnd, int version,
136				 const struct cred *cred);
137void vmci_ctx_destroy(struct vmci_ctx *context);
138
139bool vmci_ctx_supports_host_qp(struct vmci_ctx *context);
140int vmci_ctx_enqueue_datagram(u32 cid, struct vmci_datagram *dg);
141int vmci_ctx_dequeue_datagram(struct vmci_ctx *context,
142			      size_t *max_size, struct vmci_datagram **dg);
143int vmci_ctx_pending_datagrams(u32 cid, u32 *pending);
144struct vmci_ctx *vmci_ctx_get(u32 cid);
145void vmci_ctx_put(struct vmci_ctx *context);
146bool vmci_ctx_exists(u32 cid);
147
148int vmci_ctx_add_notification(u32 context_id, u32 remote_cid);
149int vmci_ctx_remove_notification(u32 context_id, u32 remote_cid);
150int vmci_ctx_get_chkpt_state(u32 context_id, u32 cpt_type,
151			     u32 *num_cids, void **cpt_buf_ptr);
152int vmci_ctx_set_chkpt_state(u32 context_id, u32 cpt_type,
153			     u32 num_cids, void *cpt_buf);
154
155int vmci_ctx_qp_create(struct vmci_ctx *context, struct vmci_handle handle);
156int vmci_ctx_qp_destroy(struct vmci_ctx *context, struct vmci_handle handle);
157bool vmci_ctx_qp_exists(struct vmci_ctx *context, struct vmci_handle handle);
158
159void vmci_ctx_check_signal_notify(struct vmci_ctx *context);
160void vmci_ctx_unset_notify(struct vmci_ctx *context);
161
162int vmci_ctx_dbell_create(u32 context_id, struct vmci_handle handle);
163int vmci_ctx_dbell_destroy(u32 context_id, struct vmci_handle handle);
164int vmci_ctx_dbell_destroy_all(u32 context_id);
165int vmci_ctx_notify_dbell(u32 cid, struct vmci_handle handle,
166			  u32 src_priv_flags);
167
168int vmci_ctx_rcv_notifications_get(u32 context_id, struct vmci_handle_arr
169				   **db_handle_array, struct vmci_handle_arr
170				   **qp_handle_array);
171void vmci_ctx_rcv_notifications_release(u32 context_id, struct vmci_handle_arr
172					*db_handle_array, struct vmci_handle_arr
173					*qp_handle_array, bool success);
174
175static inline u32 vmci_ctx_get_id(struct vmci_ctx *context)
176{
177	if (!context)
178		return VMCI_INVALID_ID;
179	return context->cid;
180}
181
182#endif /* _VMCI_CONTEXT_H_ */
183