drivers/misc/sgi-gru/grukdump.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * SN Platform GRU Driver
   4  *
   5  *            Dump GRU State
   6  *
   7  *  Copyright (c) 2008 Silicon Graphics, Inc.  All Rights Reserved.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/mm.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/uaccess.h>
  14 #include <linux/delay.h>
  15 #include <linux/bitops.h>
  16 #include <asm/uv/uv_hub.h>
  17
  18 #include <linux/nospec.h>
  19
  20 #include "gru.h"
  21 #include "grutables.h"
  22 #include "gruhandles.h"
  23 #include "grulib.h"
  24
  25 #define CCH_LOCK_ATTEMPTS       10
  26
  27 static int gru_user_copy_handle(void __user **dp, void *s)
  28 {
  29         if (copy_to_user(*dp, s, GRU_HANDLE_BYTES))
  30                 return -1;
  31         *dp += GRU_HANDLE_BYTES;
  32         return 0;
  33 }
  34
  35 static int gru_dump_context_data(void *grubase,
  36                         struct gru_context_configuration_handle *cch,
  37                         void __user *ubuf, int ctxnum, int dsrcnt,
  38                         int flush_cbrs)
  39 {
  40         void *cb, *cbe, *tfh, *gseg;
  41         int i, scr;
  42
  43         gseg = grubase + ctxnum * GRU_GSEG_STRIDE;
  44         cb = gseg + GRU_CB_BASE;
  45         cbe = grubase + GRU_CBE_BASE;
  46         tfh = grubase + GRU_TFH_BASE;
  47
  48         for_each_cbr_in_allocation_map(i, &cch->cbr_allocation_map, scr) {
  49                 if (flush_cbrs)
  50                         gru_flush_cache(cb);
  51                 if (gru_user_copy_handle(&ubuf, cb))
  52                         goto fail;
  53                 if (gru_user_copy_handle(&ubuf, tfh + i * GRU_HANDLE_STRIDE))
  54                         goto fail;
  55                 if (gru_user_copy_handle(&ubuf, cbe + i * GRU_HANDLE_STRIDE))
  56                         goto fail;
  57                 cb += GRU_HANDLE_STRIDE;
  58         }
  59         if (dsrcnt)
  60                 memcpy(ubuf, gseg + GRU_DS_BASE, dsrcnt * GRU_HANDLE_STRIDE);
  61         return 0;
  62
  63 fail:
  64         return -EFAULT;
  65 }
  66
  67 static int gru_dump_tfm(struct gru_state *gru,
  68                 void __user *ubuf, void __user *ubufend)
  69 {
  70         struct gru_tlb_fault_map *tfm;
  71         int i;
  72
  73         if (GRU_NUM_TFM * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
  74                 return -EFBIG;
  75
  76         for (i = 0; i < GRU_NUM_TFM; i++) {
  77                 tfm = get_tfm(gru->gs_gru_base_vaddr, i);
  78                 if (gru_user_copy_handle(&ubuf, tfm))
  79                         goto fail;
  80         }
  81         return GRU_NUM_TFM * GRU_CACHE_LINE_BYTES;
  82
  83 fail:
  84         return -EFAULT;
  85 }
  86
  87 static int gru_dump_tgh(struct gru_state *gru,
  88                 void __user *ubuf, void __user *ubufend)
  89 {
  90         struct gru_tlb_global_handle *tgh;
  91         int i;
  92
  93         if (GRU_NUM_TGH * GRU_CACHE_LINE_BYTES > ubufend - ubuf)
  94                 return -EFBIG;
  95
  96         for (i = 0; i < GRU_NUM_TGH; i++) {
  97                 tgh = get_tgh(gru->gs_gru_base_vaddr, i);
  98                 if (gru_user_copy_handle(&ubuf, tgh))
  99                         goto fail;
 100         }
 101         return GRU_NUM_TGH * GRU_CACHE_LINE_BYTES;
 102
 103 fail:
 104         return -EFAULT;
 105 }
 106
 107 static int gru_dump_context(struct gru_state *gru, int ctxnum,
 108                 void __user *ubuf, void __user *ubufend, char data_opt,
 109                 char lock_cch, char flush_cbrs)
 110 {
 111         struct gru_dump_context_header hdr;
 112         struct gru_dump_context_header __user *uhdr = ubuf;
 113         struct gru_context_configuration_handle *cch, *ubufcch;
 114         struct gru_thread_state *gts;
 115         int try, cch_locked, cbrcnt = 0, dsrcnt = 0, bytes = 0, ret = 0;
 116         void *grubase;
 117
 118         memset(&hdr, 0, sizeof(hdr));
 119         grubase = gru->gs_gru_base_vaddr;
 120         cch = get_cch(grubase, ctxnum);
 121         for (try = 0; try < CCH_LOCK_ATTEMPTS; try++) {
 122                 cch_locked =  trylock_cch_handle(cch);
 123                 if (cch_locked)
 124                         break;
 125                 msleep(1);
 126         }
 127
 128         ubuf += sizeof(hdr);
 129         ubufcch = ubuf;
 130         if (gru_user_copy_handle(&ubuf, cch)) {
 131                 if (cch_locked)
 132                         unlock_cch_handle(cch);
 133                 return -EFAULT;
 134         }
 135         if (cch_locked)
 136                 ubufcch->delresp = 0;
 137         bytes = sizeof(hdr) + GRU_CACHE_LINE_BYTES;
 138
 139         if (cch_locked || !lock_cch) {
 140                 gts = gru->gs_gts[ctxnum];
 141                 if (gts && gts->ts_vma) {
 142                         hdr.pid = gts->ts_tgid_owner;
 143                         hdr.vaddr = gts->ts_vma->vm_start;
 144                 }
 145                 if (cch->state != CCHSTATE_INACTIVE) {
 146                         cbrcnt = hweight64(cch->cbr_allocation_map) *
 147                                                 GRU_CBR_AU_SIZE;
 148                         dsrcnt = data_opt ? hweight32(cch->dsr_allocation_map) *
 149                                                 GRU_DSR_AU_CL : 0;
 150                 }
 151                 bytes += (3 * cbrcnt + dsrcnt) * GRU_CACHE_LINE_BYTES;
 152                 if (bytes > ubufend - ubuf)
 153                         ret = -EFBIG;
 154                 else
 155                         ret = gru_dump_context_data(grubase, cch, ubuf, ctxnum,
 156                                                         dsrcnt, flush_cbrs);
 157         }
 158         if (cch_locked)
 159                 unlock_cch_handle(cch);
 160         if (ret)
 161                 return ret;
 162
 163         hdr.magic = GRU_DUMP_MAGIC;
 164         hdr.gid = gru->gs_gid;
 165         hdr.ctxnum = ctxnum;
 166         hdr.cbrcnt = cbrcnt;
 167         hdr.dsrcnt = dsrcnt;
 168         hdr.cch_locked = cch_locked;
 169         if (copy_to_user(uhdr, &hdr, sizeof(hdr)))
 170                 return -EFAULT;
 171
 172         return bytes;
 173 }
 174
 175 int gru_dump_chiplet_request(unsigned long arg)
 176 {
 177         struct gru_state *gru;
 178         struct gru_dump_chiplet_state_req req;
 179         void __user *ubuf;
 180         void __user *ubufend;
 181         int ctxnum, ret, cnt = 0;
 182
 183         if (copy_from_user(&req, (void __user *)arg, sizeof(req)))
 184                 return -EFAULT;
 185
 186         /* Currently, only dump by gid is implemented */
 187         if (req.gid >= gru_max_gids)
 188                 return -EINVAL;
 189         req.gid = array_index_nospec(req.gid, gru_max_gids);
 190
 191         gru = GID_TO_GRU(req.gid);
 192         ubuf = req.buf;
 193         ubufend = req.buf + req.buflen;
 194
 195         ret = gru_dump_tfm(gru, ubuf, ubufend);
 196         if (ret < 0)
 197                 goto fail;
 198         ubuf += ret;
 199
 200         ret = gru_dump_tgh(gru, ubuf, ubufend);
 201         if (ret < 0)
 202                 goto fail;
 203         ubuf += ret;
 204
 205         for (ctxnum = 0; ctxnum < GRU_NUM_CCH; ctxnum++) {
 206                 if (req.ctxnum == ctxnum || req.ctxnum < 0) {
 207                         ret = gru_dump_context(gru, ctxnum, ubuf, ubufend,
 208                                                 req.data_opt, req.lock_cch,
 209                                                 req.flush_cbrs);
 210                         if (ret < 0)
 211                                 goto fail;
 212                         ubuf += ret;
 213                         cnt++;
 214                 }
 215         }
 216
 217         if (copy_to_user((void __user *)arg, &req, sizeof(req)))
 218                 return -EFAULT;
 219         return cnt;
 220
 221 fail:
 222         return ret;
 223 }