drivers/s390/cio/vfio_ccw_private.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Private stuff for vfio_ccw driver
   4  *
   5  * Copyright IBM Corp. 2017
   6  * Copyright Red Hat, Inc. 2019
   7  *
   8  * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
   9  *            Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
  10  *            Cornelia Huck <cohuck@redhat.com>
  11  */
  12
  13 #ifndef _VFIO_CCW_PRIVATE_H_
  14 #define _VFIO_CCW_PRIVATE_H_
  15
  16 #include <linux/completion.h>
  17 #include <linux/eventfd.h>
  18 #include <linux/workqueue.h>
  19 #include <linux/vfio_ccw.h>
  20 #include <asm/crw.h>
  21 #include <asm/debug.h>
  22
  23 #include "css.h"
  24 #include "vfio_ccw_cp.h"
  25
  26 #define VFIO_CCW_OFFSET_SHIFT   10
  27 #define VFIO_CCW_OFFSET_TO_INDEX(off)   (off >> VFIO_CCW_OFFSET_SHIFT)
  28 #define VFIO_CCW_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_CCW_OFFSET_SHIFT)
  29 #define VFIO_CCW_OFFSET_MASK    (((u64)(1) << VFIO_CCW_OFFSET_SHIFT) - 1)
  30
  31 /* capability chain handling similar to vfio-pci */
  32 struct vfio_ccw_private;
  33 struct vfio_ccw_region;
  34
  35 struct vfio_ccw_regops {
  36         ssize_t (*read)(struct vfio_ccw_private *private, char __user *buf,
  37                         size_t count, loff_t *ppos);
  38         ssize_t (*write)(struct vfio_ccw_private *private,
  39                          const char __user *buf, size_t count, loff_t *ppos);
  40         void    (*release)(struct vfio_ccw_private *private,
  41                            struct vfio_ccw_region *region);
  42 };
  43
  44 struct vfio_ccw_region {
  45         u32                             type;
  46         u32                             subtype;
  47         const struct vfio_ccw_regops    *ops;
  48         void                            *data;
  49         size_t                          size;
  50         u32                             flags;
  51 };
  52
  53 int vfio_ccw_register_dev_region(struct vfio_ccw_private *private,
  54                                  unsigned int subtype,
  55                                  const struct vfio_ccw_regops *ops,
  56                                  size_t size, u32 flags, void *data);
  57 void vfio_ccw_unregister_dev_regions(struct vfio_ccw_private *private);
  58
  59 int vfio_ccw_register_async_dev_regions(struct vfio_ccw_private *private);
  60 int vfio_ccw_register_schib_dev_regions(struct vfio_ccw_private *private);
  61 int vfio_ccw_register_crw_dev_regions(struct vfio_ccw_private *private);
  62
  63 struct vfio_ccw_crw {
  64         struct list_head        next;
  65         struct crw              crw;
  66 };
  67
  68 /**
  69  * struct vfio_ccw_private
  70  * @sch: pointer to the subchannel
  71  * @state: internal state of the device
  72  * @completion: synchronization helper of the I/O completion
  73  * @avail: available for creating a mediated device
  74  * @mdev: pointer to the mediated device
  75  * @nb: notifier for vfio events
  76  * @io_region: MMIO region to input/output I/O arguments/results
  77  * @io_mutex: protect against concurrent update of I/O regions
  78  * @region: additional regions for other subchannel operations
  79  * @cmd_region: MMIO region for asynchronous I/O commands other than START
  80  * @schib_region: MMIO region for SCHIB information
  81  * @crw_region: MMIO region for getting channel report words
  82  * @num_regions: number of additional regions
  83  * @cp: channel program for the current I/O operation
  84  * @irb: irb info received from interrupt
  85  * @scsw: scsw info
  86  * @io_trigger: eventfd ctx for signaling userspace I/O results
  87  * @crw_trigger: eventfd ctx for signaling userspace CRW information
  88  * @req_trigger: eventfd ctx for signaling userspace to return device
  89  * @io_work: work for deferral process of I/O handling
  90  * @crw_work: work for deferral process of CRW handling
  91  */
  92 struct vfio_ccw_private {
  93         struct subchannel       *sch;
  94         int                     state;
  95         struct completion       *completion;
  96         atomic_t                avail;
  97         struct mdev_device      *mdev;
  98         struct notifier_block   nb;
  99         struct ccw_io_region    *io_region;
 100         struct mutex            io_mutex;
 101         struct vfio_ccw_region *region;
 102         struct ccw_cmd_region   *cmd_region;
 103         struct ccw_schib_region *schib_region;
 104         struct ccw_crw_region   *crw_region;
 105         int num_regions;
 106
 107         struct channel_program  cp;
 108         struct irb              irb;
 109         union scsw              scsw;
 110         struct list_head        crw;
 111
 112         struct eventfd_ctx      *io_trigger;
 113         struct eventfd_ctx      *crw_trigger;
 114         struct eventfd_ctx      *req_trigger;
 115         struct work_struct      io_work;
 116         struct work_struct      crw_work;
 117 } __aligned(8);
 118
 119 extern int vfio_ccw_mdev_reg(struct subchannel *sch);
 120 extern void vfio_ccw_mdev_unreg(struct subchannel *sch);
 121
 122 extern int vfio_ccw_sch_quiesce(struct subchannel *sch);
 123
 124 /*
 125  * States of the device statemachine.
 126  */
 127 enum vfio_ccw_state {
 128         VFIO_CCW_STATE_NOT_OPER,
 129         VFIO_CCW_STATE_STANDBY,
 130         VFIO_CCW_STATE_IDLE,
 131         VFIO_CCW_STATE_CP_PROCESSING,
 132         VFIO_CCW_STATE_CP_PENDING,
 133         /* last element! */
 134         NR_VFIO_CCW_STATES
 135 };
 136
 137 /*
 138  * Asynchronous events of the device statemachine.
 139  */
 140 enum vfio_ccw_event {
 141         VFIO_CCW_EVENT_NOT_OPER,
 142         VFIO_CCW_EVENT_IO_REQ,
 143         VFIO_CCW_EVENT_INTERRUPT,
 144         VFIO_CCW_EVENT_ASYNC_REQ,
 145         /* last element! */
 146         NR_VFIO_CCW_EVENTS
 147 };
 148
 149 /*
 150  * Action called through jumptable.
 151  */
 152 typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event);
 153 extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];
 154
 155 static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
 156                                      int event)
 157 {
 158         trace_vfio_ccw_fsm_event(private->sch->schid, private->state, event);
 159         vfio_ccw_jumptable[private->state][event](private, event);
 160 }
 161
 162 extern struct workqueue_struct *vfio_ccw_work_q;
 163
 164
 165 /* s390 debug feature, similar to base cio */
 166 extern debug_info_t *vfio_ccw_debug_msg_id;
 167 extern debug_info_t *vfio_ccw_debug_trace_id;
 168
 169 #define VFIO_CCW_TRACE_EVENT(imp, txt) \
 170                 debug_text_event(vfio_ccw_debug_trace_id, imp, txt)
 171
 172 #define VFIO_CCW_MSG_EVENT(imp, args...) \
 173                 debug_sprintf_event(vfio_ccw_debug_msg_id, imp, ##args)
 174
 175 static inline void VFIO_CCW_HEX_EVENT(int level, void *data, int length)
 176 {
 177         debug_event(vfio_ccw_debug_trace_id, level, data, length);
 178 }
 179
 180 #endif