drivers/infiniband/hw/ehca/ipz_pt_fn.h

   1 /*
   2  *  IBM eServer eHCA Infiniband device driver for Linux on POWER
   3  *
   4  *  internal queue handling
   5  *
   6  *  Authors: Waleri Fomin <fomin@de.ibm.com>
   7  *           Reinhard Ernst <rernst@de.ibm.com>
   8  *           Christoph Raisch <raisch@de.ibm.com>
   9  *
  10  *  Copyright (c) 2005 IBM Corporation
  11  *
  12  *  All rights reserved.
  13  *
  14  *  This source code is distributed under a dual license of GPL v2.0 and OpenIB
  15  *  BSD.
  16  *
  17  * OpenIB BSD License
  18  *
  19  * Redistribution and use in source and binary forms, with or without
  20  * modification, are permitted provided that the following conditions are met:
  21  *
  22  * Redistributions of source code must retain the above copyright notice, this
  23  * list of conditions and the following disclaimer.
  24  *
  25  * Redistributions in binary form must reproduce the above copyright notice,
  26  * this list of conditions and the following disclaimer in the documentation
  27  * and/or other materials
  28  * provided with the distribution.
  29  *
  30  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  31  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  33  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  34  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  35  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  36  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  37  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  38  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  39  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  40  * POSSIBILITY OF SUCH DAMAGE.
  41  */
  42
  43 #ifndef __IPZ_PT_FN_H__
  44 #define __IPZ_PT_FN_H__
  45
  46 #define EHCA_PAGESHIFT   12
  47 #define EHCA_PAGESIZE   4096UL
  48 #define EHCA_PAGEMASK   (~(EHCA_PAGESIZE-1))
  49 #define EHCA_PT_ENTRIES 512UL
  50
  51 #include "ehca_tools.h"
  52 #include "ehca_qes.h"
  53
  54 struct ehca_pd;
  55 struct ipz_small_queue_page;
  56
  57 extern struct kmem_cache *small_qp_cache;
  58
  59 /* struct generic ehca page */
  60 struct ipz_page {
  61         u8 entries[EHCA_PAGESIZE];
  62 };
  63
  64 #define IPZ_SPAGE_PER_KPAGE (PAGE_SIZE / 512)
  65
  66 struct ipz_small_queue_page {
  67         unsigned long page;
  68         unsigned long bitmap[IPZ_SPAGE_PER_KPAGE / BITS_PER_LONG];
  69         int fill;
  70         void *mapped_addr;
  71         u32 mmap_count;
  72         struct list_head list;
  73 };
  74
  75 /* struct generic queue in linux kernel virtual memory (kv) */
  76 struct ipz_queue {
  77         u64 current_q_offset;   /* current queue entry */
  78
  79         struct ipz_page **queue_pages;  /* array of pages belonging to queue */
  80         u32 qe_size;            /* queue entry size */
  81         u32 act_nr_of_sg;
  82         u32 queue_length;       /* queue length allocated in bytes */
  83         u32 pagesize;
  84         u32 toggle_state;       /* toggle flag - per page */
  85         u32 offset; /* save offset within page for small_qp */
  86         struct ipz_small_queue_page *small_page;
  87 };
  88
  89 /*
  90  * return current Queue Entry for a certain q_offset
  91  * returns address (kv) of Queue Entry
  92  */
  93 static inline void *ipz_qeit_calc(struct ipz_queue *queue, u64 q_offset)
  94 {
  95         struct ipz_page *current_page;
  96         if (q_offset >= queue->queue_length)
  97                 return NULL;
  98         current_page = (queue->queue_pages)[q_offset >> EHCA_PAGESHIFT];
  99         return &current_page->entries[q_offset & (EHCA_PAGESIZE - 1)];
 100 }
 101
 102 /*
 103  * return current Queue Entry
 104  * returns address (kv) of Queue Entry
 105  */
 106 static inline void *ipz_qeit_get(struct ipz_queue *queue)
 107 {
 108         return ipz_qeit_calc(queue, queue->current_q_offset);
 109 }
 110
 111 /*
 112  * return current Queue Page , increment Queue Page iterator from
 113  * page to page in struct ipz_queue, last increment will return 0! and
 114  * NOT wrap
 115  * returns address (kv) of Queue Page
 116  * warning don't use in parallel with ipz_QE_get_inc()
 117  */
 118 void *ipz_qpageit_get_inc(struct ipz_queue *queue);
 119
 120 /*
 121  * return current Queue Entry, increment Queue Entry iterator by one
 122  * step in struct ipz_queue, will wrap in ringbuffer
 123  * returns address (kv) of Queue Entry BEFORE increment
 124  * warning don't use in parallel with ipz_qpageit_get_inc()
 125  */
 126 static inline void *ipz_qeit_get_inc(struct ipz_queue *queue)
 127 {
 128         void *ret = ipz_qeit_get(queue);
 129         queue->current_q_offset += queue->qe_size;
 130         if (queue->current_q_offset >= queue->queue_length) {
 131                 queue->current_q_offset = 0;
 132                 /* toggle the valid flag */
 133                 queue->toggle_state = (~queue->toggle_state) & 1;
 134         }
 135
 136         return ret;
 137 }
 138
 139 /*
 140  * return a bool indicating whether current Queue Entry is valid
 141  */
 142 static inline int ipz_qeit_is_valid(struct ipz_queue *queue)
 143 {
 144         struct ehca_cqe *cqe = ipz_qeit_get(queue);
 145         return ((cqe->cqe_flags >> 7) == (queue->toggle_state & 1));
 146 }
 147
 148 /*
 149  * return current Queue Entry, increment Queue Entry iterator by one
 150  * step in struct ipz_queue, will wrap in ringbuffer
 151  * returns address (kv) of Queue Entry BEFORE increment
 152  * returns 0 and does not increment, if wrong valid state
 153  * warning don't use in parallel with ipz_qpageit_get_inc()
 154  */
 155 static inline void *ipz_qeit_get_inc_valid(struct ipz_queue *queue)
 156 {
 157         return ipz_qeit_is_valid(queue) ? ipz_qeit_get_inc(queue) : NULL;
 158 }
 159
 160 /*
 161  * returns and resets Queue Entry iterator
 162  * returns address (kv) of first Queue Entry
 163  */
 164 static inline void *ipz_qeit_reset(struct ipz_queue *queue)
 165 {
 166         queue->current_q_offset = 0;
 167         return ipz_qeit_get(queue);
 168 }
 169
 170 /*
 171  * return the q_offset corresponding to an absolute address
 172  */
 173 int ipz_queue_abs_to_offset(struct ipz_queue *queue, u64 addr, u64 *q_offset);
 174
 175 /*
 176  * return the next queue offset. don't modify the queue.
 177  */
 178 static inline u64 ipz_queue_advance_offset(struct ipz_queue *queue, u64 offset)
 179 {
 180         offset += queue->qe_size;
 181         if (offset >= queue->queue_length) offset = 0;
 182         return offset;
 183 }
 184
 185 /* struct generic page table */
 186 struct ipz_pt {
 187         u64 entries[EHCA_PT_ENTRIES];
 188 };
 189
 190 /* struct page table for a queue, only to be used in pf */
 191 struct ipz_qpt {
 192         /* queue page tables (kv), use u64 because we know the element length */
 193         u64 *qpts;
 194         u32 n_qpts;
 195         u32 n_ptes;       /*  number of page table entries */
 196         u64 *current_pte_addr;
 197 };
 198
 199 /*
 200  * constructor for a ipz_queue_t, placement new for ipz_queue_t,
 201  * new for all dependent datastructors
 202  * all QP Tables are the same
 203  * flow:
 204  *    allocate+pin queue
 205  * see ipz_qpt_ctor()
 206  * returns true if ok, false if out of memory
 207  */
 208 int ipz_queue_ctor(struct ehca_pd *pd, struct ipz_queue *queue,
 209                    const u32 nr_of_pages, const u32 pagesize,
 210                    const u32 qe_size, const u32 nr_of_sg,
 211                    int is_small);
 212
 213 /*
 214  * destructor for a ipz_queue_t
 215  *  -# free queue
 216  *  see ipz_queue_ctor()
 217  *  returns true if ok, false if queue was NULL-ptr of free failed
 218  */
 219 int ipz_queue_dtor(struct ehca_pd *pd, struct ipz_queue *queue);
 220
 221 /*
 222  * constructor for a ipz_qpt_t,
 223  * placement new for struct ipz_queue, new for all dependent datastructors
 224  * all QP Tables are the same,
 225  * flow:
 226  * -# allocate+pin queue
 227  * -# initialise ptcb
 228  * -# allocate+pin PTs
 229  * -# link PTs to a ring, according to HCA Arch, set bit62 id needed
 230  * -# the ring must have room for exactly nr_of_PTEs
 231  * see ipz_qpt_ctor()
 232  */
 233 void ipz_qpt_ctor(struct ipz_qpt *qpt,
 234                   const u32 nr_of_qes,
 235                   const u32 pagesize,
 236                   const u32 qe_size,
 237                   const u8 lowbyte, const u8 toggle,
 238                   u32 * act_nr_of_QEs, u32 * act_nr_of_pages);
 239
 240 /*
 241  * return current Queue Entry, increment Queue Entry iterator by one
 242  * step in struct ipz_queue, will wrap in ringbuffer
 243  * returns address (kv) of Queue Entry BEFORE increment
 244  * warning don't use in parallel with ipz_qpageit_get_inc()
 245  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 246  * fix EQ page problems
 247  */
 248 void *ipz_qeit_eq_get_inc(struct ipz_queue *queue);
 249
 250 /*
 251  * return current Event Queue Entry, increment Queue Entry iterator
 252  * by one step in struct ipz_queue if valid, will wrap in ringbuffer
 253  * returns address (kv) of Queue Entry BEFORE increment
 254  * returns 0 and does not increment, if wrong valid state
 255  * warning don't use in parallel with ipz_queue_QPageit_get_inc()
 256  * warning unpredictable results may occur if steps>act_nr_of_queue_entries
 257  */
 258 static inline void *ipz_eqit_eq_get_inc_valid(struct ipz_queue *queue)
 259 {
 260         void *ret = ipz_qeit_get(queue);
 261         u32 qe = *(u8 *)ret;
 262         if ((qe >> 7) != (queue->toggle_state & 1))
 263                 return NULL;
 264         ipz_qeit_eq_get_inc(queue); /* this is a good one */
 265         return ret;
 266 }
 267
 268 static inline void *ipz_eqit_eq_peek_valid(struct ipz_queue *queue)
 269 {
 270         void *ret = ipz_qeit_get(queue);
 271         u32 qe = *(u8 *)ret;
 272         if ((qe >> 7) != (queue->toggle_state & 1))
 273                 return NULL;
 274         return ret;
 275 }
 276
 277 /* returns address (GX) of first queue entry */
 278 static inline u64 ipz_qpt_get_firstpage(struct ipz_qpt *qpt)
 279 {
 280         return be64_to_cpu(qpt->qpts[0]);
 281 }
 282
 283 /* returns address (kv) of first page of queue page table */
 284 static inline void *ipz_qpt_get_qpt(struct ipz_qpt *qpt)
 285 {
 286         return qpt->qpts;
 287 }
 288
 289 #endif                          /* __IPZ_PT_FN_H__ */