drivers/misc/sgi-gru/grukdump.c

   1 /*
   2  * SN Platform GRU Driver
   3  *
   4  *            Dump GRU State
   5  *
   6  *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/mm.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/delay.h>
  28 #include <linux/bitops.h>
  29 #include <asm/uv/uv_hub.h>
  30
  31 #include <linux/nospec.h>
  32
  33 #include "gru.h"
  34 #include "grutables.h"
  35 #include "gruhandles.h"
  36 #include "grulib.h"
  37
  38 #define CCH_LOCK_ATTEMPTS       10
  39
  40 static int gru_user_copy_handle(void __user **dp, void *s)
  41 {
  42         if (copy_to_user(*dp, s, GRU_HANDLE_BYTES))
  43                 return -1;
  44         *dp += GRU_HANDLE_BYTES;
  45         return 0;
  46 }
  47
  48 static int gru_dump_context_data(void *grubase,
  49                         struct gru_context_configuration_handle *cch,
  50                         void __user *ubuf, int ctxnum, int dsrcnt,
  51                         int flush_cbrs)
  52 {
  53         void *cb, *cbe, *tfh, *gseg;
  54         int i, scr;
  55
  56         gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
  57         cb = gseg + GRU_CB_BASE;
  58         cbe = grubase + GRU_CBE_BASE;
  59         tfh = grubase + GRU_TFH_BASE;
  60
  61         for_each_cbr_in_allocation_map(i, &cch->cbr_allocation_map, scr) {
  62                 if (flush_cbrs)
  63                         gru_flush_cache(cb);
  64                 if (gru_user_copy_handle(&ubuf, cb))
  65                         goto fail;
  66                 if (gru_user_copy_handle(&ubuf, tfh + i * GRU_HANDLE_STRIDE))
  67                         goto fail;
  68                 if (gru_user_copy_handle(&ubuf, cbe + i * GRU_HANDLE_STRIDE))
  69                         goto fail;
  70                 cb += GRU_HANDLE_STRIDE;
  71         }
  72         if (dsrcnt)
  73                 memcpy(ubuf, gseg + GRU_DS_BASE, dsrcnt * GRU_HANDLE_STRIDE);
  74         return 0;
  75
  76 fail:
  77         return -EFAULT;
  78 }
  79
  80 static int gru_dump_tfm(struct gru_state *gru,
  81                 void __user *ubuf, void __user *ubufend)
  82 {
  83         struct gru_tlb_fault_map *tfm;
  84         int i;
  85
  86         if (GRU_NUM_TFM * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
  87                 return -EFBIG;
  88
  89         for (i = 0; i < GRU_NUM_TFM; i++) {
  90                 tfm = get_tfm(gru->gs_gru_base_vaddr, i);
  91                 if (gru_user_copy_handle(&ubuf, tfm))
  92                         goto fail;
  93         }
  94         return GRU_NUM_TFM * GRU_CACHE_LINE_BYTES;
  95
  96 fail:
  97         return -EFAULT;
  98 }
  99
 100 static int gru_dump_tgh(struct gru_state *gru,
 101                 void __user *ubuf, void __user *ubufend)
 102 {
 103         struct gru_tlb_global_handle *tgh;
 104         int i;
 105
 106         if (GRU_NUM_TGH * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
 107                 return -EFBIG;
 108
 109         for (i = 0; i < GRU_NUM_TGH; i++) {
 110                 tgh = get_tgh(gru->gs_gru_base_vaddr, i);
 111                 if (gru_user_copy_handle(&ubuf, tgh))
 112                         goto fail;
 113         }
 114         return GRU_NUM_TGH * GRU_CACHE_LINE_BYTES;
 115
 116 fail:
 117         return -EFAULT;
 118 }
 119
 120 static int gru_dump_context(struct gru_state *gru, int ctxnum,
 121                 void __user *ubuf, void __user *ubufend, char data_opt,
 122                 char lock_cch, char flush_cbrs)
 123 {
 124         struct gru_dump_context_header hdr;
 125         struct gru_dump_context_header __user *uhdr = ubuf;
 126         struct gru_context_configuration_handle *cch, *ubufcch;
 127         struct gru_thread_state *gts;
 128         int try, cch_locked, cbrcnt = 0, dsrcnt = 0, bytes = 0, ret = 0;
 129         void *grubase;
 130
 131         memset(&hdr, 0, sizeof(hdr));
 132         grubase = gru->gs_gru_base_vaddr;
 133         cch = get_cch(grubase, ctxnum);
 134         for (try = 0; try < CCH_LOCK_ATTEMPTS; try++) {
 135                 cch_locked =  trylock_cch_handle(cch);
 136                 if (cch_locked)
 137                         break;
 138                 msleep(1);
 139         }
 140
 141         ubuf += sizeof(hdr);
 142         ubufcch = ubuf;
 143         if (gru_user_copy_handle(&ubuf, cch)) {
 144                 if (cch_locked)
 145                         unlock_cch_handle(cch);
 146                 return -EFAULT;
 147         }
 148         if (cch_locked)
 149                 ubufcch->delresp = 0;
 150         bytes = sizeof(hdr) + GRU_CACHE_LINE_BYTES;
 151
 152         if (cch_locked || !lock_cch) {
 153                 gts = gru->gs_gts[ctxnum];
 154                 if (gts && gts->ts_vma) {
 155                         hdr.pid = gts->ts_tgid_owner;
 156                         hdr.vaddr = gts->ts_vma->vm_start;
 157                 }
 158                 if (cch->state != CCHSTATE_INACTIVE) {
 159                         cbrcnt = hweight64(cch->cbr_allocation_map) *
 160                                                 GRU_CBR_AU_SIZE;
 161                         dsrcnt = data_opt ? hweight32(cch->dsr_allocation_map) *
 162                                                 GRU_DSR_AU_CL : 0;
 163                 }
 164                 bytes += (3 * cbrcnt + dsrcnt) * GRU_CACHE_LINE_BYTES;
 165                 if (bytes > ubufend - ubuf)
 166                         ret = -EFBIG;
 167                 else
 168                         ret = gru_dump_context_data(grubase, cch, ubuf, ctxnum,
 169                                                         dsrcnt, flush_cbrs);
 170         }
 171         if (cch_locked)
 172                 unlock_cch_handle(cch);
 173         if (ret)
 174                 return ret;
 175
 176         hdr.magic = GRU_DUMP_MAGIC;
 177         hdr.gid = gru->gs_gid;
 178         hdr.ctxnum = ctxnum;
 179         hdr.cbrcnt = cbrcnt;
 180         hdr.dsrcnt = dsrcnt;
 181         hdr.cch_locked = cch_locked;
 182         if (copy_to_user(uhdr, &hdr, sizeof(hdr)))
 183                 return -EFAULT;
 184
 185         return bytes;
 186 }
 187
 188 int gru_dump_chiplet_request(unsigned long arg)
 189 {
 190         struct gru_state *gru;
 191         struct gru_dump_chiplet_state_req req;
 192         void __user *ubuf;
 193         void __user *ubufend;
 194         int ctxnum, ret, cnt = 0;
 195
 196         if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
 197                 return -EFAULT;
 198
 199         /* Currently, only dump by gid is implemented */
 200         if (req.gid >= gru_max_gids)
 201                 return -EINVAL;
 202         req.gid = array_index_nospec(req.gid, gru_max_gids);
 203
 204         gru = GID_TO_GRU(req.gid);
 205         ubuf = req.buf;
 206         ubufend = req.buf + req.buflen;
 207
 208         ret = gru_dump_tfm(gru, ubuf, ubufend);
 209         if (ret < 0)
 210                 goto fail;
 211         ubuf += ret;
 212
 213         ret = gru_dump_tgh(gru, ubuf, ubufend);
 214         if (ret < 0)
 215                 goto fail;
 216         ubuf += ret;
 217
 218         for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) {
 219                 if (req.ctxnum == ctxnum || req.ctxnum < 0) {
 220                         ret = gru_dump_context(gru, ctxnum, ubuf, ubufend,
 221                                                 req.data_opt, req.lock_cch,
 222                                                 req.flush_cbrs);
 223                         if (ret < 0)
 224                                 goto fail;
 225                         ubuf += ret;
 226                         cnt++;
 227                 }
 228         }
 229
 230         if (copy_to_user((void __user *)arg, &req, sizeof(req)))
 231                 return -EFAULT;
 232         return cnt;
 233
 234 fail:
 235         return ret;
 236 }