linux/drivers/misc/sgi-gru/grukdump.c
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   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
  27static 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
  35static 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
  63fail:
  64        return -EFAULT;
  65}
  66
  67static 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
  83fail:
  84        return -EFAULT;
  85}
  86
  87static 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
 103fail:
 104        return -EFAULT;
 105}
 106
 107static 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
 175int 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
 221fail:
 222        return ret;
 223}
 224