drivers/misc/vmw_vmci/vmci_queue_pair.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * VMware VMCI Driver
   4  *
   5  * Copyright (C) 2012 VMware, Inc. All rights reserved.
   6  */
   7
   8 #ifndef _VMCI_QUEUE_PAIR_H_
   9 #define _VMCI_QUEUE_PAIR_H_
  10
  11 #include <linux/vmw_vmci_defs.h>
  12 #include <linux/types.h>
  13
  14 #include "vmci_context.h"
  15
  16 /* Callback needed for correctly waiting on events. */
  17 typedef int (*vmci_event_release_cb) (void *client_data);
  18
  19 /* Guest device port I/O. */
  20 struct ppn_set {
  21         u64 num_produce_pages;
  22         u64 num_consume_pages;
  23         u64 *produce_ppns;
  24         u64 *consume_ppns;
  25         bool initialized;
  26 };
  27
  28 /* VMCIqueue_pairAllocInfo */
  29 struct vmci_qp_alloc_info {
  30         struct vmci_handle handle;
  31         u32 peer;
  32         u32 flags;
  33         u64 produce_size;
  34         u64 consume_size;
  35         u64 ppn_va;     /* Start VA of queue pair PPNs. */
  36         u64 num_ppns;
  37         s32 result;
  38         u32 version;
  39 };
  40
  41 /* VMCIqueue_pairSetVAInfo */
  42 struct vmci_qp_set_va_info {
  43         struct vmci_handle handle;
  44         u64 va;         /* Start VA of queue pair PPNs. */
  45         u64 num_ppns;
  46         u32 version;
  47         s32 result;
  48 };
  49
  50 /*
  51  * For backwards compatibility, here is a version of the
  52  * VMCIqueue_pairPageFileInfo before host support end-points was added.
  53  * Note that the current version of that structure requires VMX to
  54  * pass down the VA of the mapped file.  Before host support was added
  55  * there was nothing of the sort.  So, when the driver sees the ioctl
  56  * with a parameter that is the sizeof
  57  * VMCIqueue_pairPageFileInfo_NoHostQP then it can infer that the version
  58  * of VMX running can't attach to host end points because it doesn't
  59  * provide the VA of the mapped files.
  60  *
  61  * The Linux driver doesn't get an indication of the size of the
  62  * structure passed down from user space.  So, to fix a long standing
  63  * but unfiled bug, the _pad field has been renamed to version.
  64  * Existing versions of VMX always initialize the PageFileInfo
  65  * structure so that _pad, er, version is set to 0.
  66  *
  67  * A version value of 1 indicates that the size of the structure has
  68  * been increased to include two UVA's: produce_uva and consume_uva.
  69  * These UVA's are of the mmap()'d queue contents backing files.
  70  *
  71  * In addition, if when VMX is sending down the
  72  * VMCIqueue_pairPageFileInfo structure it gets an error then it will
  73  * try again with the _NoHostQP version of the file to see if an older
  74  * VMCI kernel module is running.
  75  */
  76
  77 /* VMCIqueue_pairPageFileInfo */
  78 struct vmci_qp_page_file_info {
  79         struct vmci_handle handle;
  80         u64 produce_page_file;    /* User VA. */
  81         u64 consume_page_file;    /* User VA. */
  82         u64 produce_page_file_size;  /* Size of the file name array. */
  83         u64 consume_page_file_size;  /* Size of the file name array. */
  84         s32 result;
  85         u32 version;    /* Was _pad. */
  86         u64 produce_va; /* User VA of the mapped file. */
  87         u64 consume_va; /* User VA of the mapped file. */
  88 };
  89
  90 /* vmci queuepair detach info */
  91 struct vmci_qp_dtch_info {
  92         struct vmci_handle handle;
  93         s32 result;
  94         u32 _pad;
  95 };
  96
  97 /*
  98  * struct vmci_qp_page_store describes how the memory of a given queue pair
  99  * is backed. When the queue pair is between the host and a guest, the
 100  * page store consists of references to the guest pages. On vmkernel,
 101  * this is a list of PPNs, and on hosted, it is a user VA where the
 102  * queue pair is mapped into the VMX address space.
 103  */
 104 struct vmci_qp_page_store {
 105         /* Reference to pages backing the queue pair. */
 106         u64 pages;
 107         /* Length of pageList/virtual addres range (in pages). */
 108         u32 len;
 109 };
 110
 111 /*
 112  * This data type contains the information about a queue.
 113  * There are two queues (hence, queue pairs) per transaction model between a
 114  * pair of end points, A & B.  One queue is used by end point A to transmit
 115  * commands and responses to B.  The other queue is used by B to transmit
 116  * commands and responses.
 117  *
 118  * struct vmci_queue_kern_if is a per-OS defined Queue structure.  It contains
 119  * either a direct pointer to the linear address of the buffer contents or a
 120  * pointer to structures which help the OS locate those data pages.  See
 121  * vmciKernelIf.c for each platform for its definition.
 122  */
 123 struct vmci_queue {
 124         struct vmci_queue_header *q_header;
 125         struct vmci_queue_header *saved_header;
 126         struct vmci_queue_kern_if *kernel_if;
 127 };
 128
 129 /*
 130  * Utility function that checks whether the fields of the page
 131  * store contain valid values.
 132  * Result:
 133  * true if the page store is wellformed. false otherwise.
 134  */
 135 static inline bool
 136 VMCI_QP_PAGESTORE_IS_WELLFORMED(struct vmci_qp_page_store *page_store)
 137 {
 138         return page_store->len >= 2;
 139 }
 140
 141 void vmci_qp_broker_exit(void);
 142 int vmci_qp_broker_alloc(struct vmci_handle handle, u32 peer,
 143                          u32 flags, u32 priv_flags,
 144                          u64 produce_size, u64 consume_size,
 145                          struct vmci_qp_page_store *page_store,
 146                          struct vmci_ctx *context);
 147 int vmci_qp_broker_set_page_store(struct vmci_handle handle,
 148                                   u64 produce_uva, u64 consume_uva,
 149                                   struct vmci_ctx *context);
 150 int vmci_qp_broker_detach(struct vmci_handle handle, struct vmci_ctx *context);
 151
 152 void vmci_qp_guest_endpoints_exit(void);
 153
 154 int vmci_qp_alloc(struct vmci_handle *handle,
 155                   struct vmci_queue **produce_q, u64 produce_size,
 156                   struct vmci_queue **consume_q, u64 consume_size,
 157                   u32 peer, u32 flags, u32 priv_flags,
 158                   bool guest_endpoint, vmci_event_release_cb wakeup_cb,
 159                   void *client_data);
 160 int vmci_qp_broker_map(struct vmci_handle handle,
 161                        struct vmci_ctx *context, u64 guest_mem);
 162 int vmci_qp_broker_unmap(struct vmci_handle handle,
 163                          struct vmci_ctx *context, u32 gid);
 164
 165 #endif /* _VMCI_QUEUE_PAIR_H_ */