drivers/misc/vmw_vmci/vmci_queue_pair.h

   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
 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_ */