1 /*
2  * VMware VMCI Driver
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_QUEUE_PAIR_H_
17 #define _VMCI_QUEUE_PAIR_H_
18 
19 #include <linux/vmw_vmci_defs.h>
20 #include <linux/types.h>
21 
22 #include "vmci_context.h"
23 
24 /* Callback needed for correctly waiting on events. */
25 typedef int (*vmci_event_release_cb) (void *client_data);
26 
27 /* Guest device port I/O. */
28 struct ppn_set {
29 	u64 num_produce_pages;
30 	u64 num_consume_pages;
31 	u32 *produce_ppns;
32 	u32 *consume_ppns;
33 	bool initialized;
34 };
35 
36 /* VMCIqueue_pairAllocInfo */
37 struct vmci_qp_alloc_info {
38 	struct vmci_handle handle;
39 	u32 peer;
40 	u32 flags;
41 	u64 produce_size;
42 	u64 consume_size;
43 	u64 ppn_va;	/* Start VA of queue pair PPNs. */
44 	u64 num_ppns;
45 	s32 result;
46 	u32 version;
47 };
48 
49 /* VMCIqueue_pairSetVAInfo */
50 struct vmci_qp_set_va_info {
51 	struct vmci_handle handle;
52 	u64 va;		/* Start VA of queue pair PPNs. */
53 	u64 num_ppns;
54 	u32 version;
55 	s32 result;
56 };
57 
58 /*
59  * For backwards compatibility, here is a version of the
60  * VMCIqueue_pairPageFileInfo before host support end-points was added.
61  * Note that the current version of that structure requires VMX to
62  * pass down the VA of the mapped file.  Before host support was added
63  * there was nothing of the sort.  So, when the driver sees the ioctl
64  * with a parameter that is the sizeof
65  * VMCIqueue_pairPageFileInfo_NoHostQP then it can infer that the version
66  * of VMX running can't attach to host end points because it doesn't
67  * provide the VA of the mapped files.
68  *
69  * The Linux driver doesn't get an indication of the size of the
70  * structure passed down from user space.  So, to fix a long standing
71  * but unfiled bug, the _pad field has been renamed to version.
72  * Existing versions of VMX always initialize the PageFileInfo
73  * structure so that _pad, er, version is set to 0.
74  *
75  * A version value of 1 indicates that the size of the structure has
76  * been increased to include two UVA's: produce_uva and consume_uva.
77  * These UVA's are of the mmap()'d queue contents backing files.
78  *
79  * In addition, if when VMX is sending down the
80  * VMCIqueue_pairPageFileInfo structure it gets an error then it will
81  * try again with the _NoHostQP version of the file to see if an older
82  * VMCI kernel module is running.
83  */
84 
85 /* VMCIqueue_pairPageFileInfo */
86 struct vmci_qp_page_file_info {
87 	struct vmci_handle handle;
88 	u64 produce_page_file;	  /* User VA. */
89 	u64 consume_page_file;	  /* User VA. */
90 	u64 produce_page_file_size;  /* Size of the file name array. */
91 	u64 consume_page_file_size;  /* Size of the file name array. */
92 	s32 result;
93 	u32 version;	/* Was _pad. */
94 	u64 produce_va;	/* User VA of the mapped file. */
95 	u64 consume_va;	/* User VA of the mapped file. */
96 };
97 
98 /* vmci queuepair detach info */
99 struct vmci_qp_dtch_info {
100 	struct vmci_handle handle;
101 	s32 result;
102 	u32 _pad;
103 };
104 
105 /*
106  * struct vmci_qp_page_store describes how the memory of a given queue pair
107  * is backed. When the queue pair is between the host and a guest, the
108  * page store consists of references to the guest pages. On vmkernel,
109  * this is a list of PPNs, and on hosted, it is a user VA where the
110  * queue pair is mapped into the VMX address space.
111  */
112 struct vmci_qp_page_store {
113 	/* Reference to pages backing the queue pair. */
114 	u64 pages;
115 	/* Length of pageList/virtual addres range (in pages). */
116 	u32 len;
117 };
118 
119 /*
120  * This data type contains the information about a queue.
121  * There are two queues (hence, queue pairs) per transaction model between a
122  * pair of end points, A & B.  One queue is used by end point A to transmit
123  * commands and responses to B.  The other queue is used by B to transmit
124  * commands and responses.
125  *
126  * struct vmci_queue_kern_if is a per-OS defined Queue structure.  It contains
127  * either a direct pointer to the linear address of the buffer contents or a
128  * pointer to structures which help the OS locate those data pages.  See
129  * vmciKernelIf.c for each platform for its definition.
130  */
131 struct vmci_queue {
132 	struct vmci_queue_header *q_header;
133 	struct vmci_queue_header *saved_header;
134 	struct vmci_queue_kern_if *kernel_if;
135 };
136 
137 /*
138  * Utility function that checks whether the fields of the page
139  * store contain valid values.
140  * Result:
141  * true if the page store is wellformed. false otherwise.
142  */
143 static inline bool
VMCI_QP_PAGESTORE_IS_WELLFORMED(struct vmci_qp_page_store * page_store)144 VMCI_QP_PAGESTORE_IS_WELLFORMED(struct vmci_qp_page_store *page_store)
145 {
146 	return page_store->len >= 2;
147 }
148 
149 void vmci_qp_broker_exit(void);
150 int vmci_qp_broker_alloc(struct vmci_handle handle, u32 peer,
151 			 u32 flags, u32 priv_flags,
152 			 u64 produce_size, u64 consume_size,
153 			 struct vmci_qp_page_store *page_store,
154 			 struct vmci_ctx *context);
155 int vmci_qp_broker_set_page_store(struct vmci_handle handle,
156 				  u64 produce_uva, u64 consume_uva,
157 				  struct vmci_ctx *context);
158 int vmci_qp_broker_detach(struct vmci_handle handle, struct vmci_ctx *context);
159 
160 void vmci_qp_guest_endpoints_exit(void);
161 
162 int vmci_qp_alloc(struct vmci_handle *handle,
163 		  struct vmci_queue **produce_q, u64 produce_size,
164 		  struct vmci_queue **consume_q, u64 consume_size,
165 		  u32 peer, u32 flags, u32 priv_flags,
166 		  bool guest_endpoint, vmci_event_release_cb wakeup_cb,
167 		  void *client_data);
168 int vmci_qp_broker_map(struct vmci_handle handle,
169 		       struct vmci_ctx *context, u64 guest_mem);
170 int vmci_qp_broker_unmap(struct vmci_handle handle,
171 			 struct vmci_ctx *context, u32 gid);
172 
173 #endif /* _VMCI_QUEUE_PAIR_H_ */
174