init/do_mounts_md.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/delay.h>
   3 #include <linux/raid/md_u.h>
   4 #include <linux/raid/md_p.h>
   5
   6 #include "do_mounts.h"
   7
   8 /*
   9  * When md (and any require personalities) are compiled into the kernel
  10  * (not a module), arrays can be assembles are boot time using with AUTODETECT
  11  * where specially marked partitions are registered with md_autodetect_dev(),
  12  * and with MD_BOOT where devices to be collected are given on the boot line
  13  * with md=.....
  14  * The code for that is here.
  15  */
  16
  17 #ifdef CONFIG_MD_AUTODETECT
  18 static int __initdata raid_noautodetect;
  19 #else
  20 static int __initdata raid_noautodetect=1;
  21 #endif
  22 static int __initdata raid_autopart;
  23
  24 static struct {
  25         int minor;
  26         int partitioned;
  27         int level;
  28         int chunk;
  29         char *device_names;
  30 } md_setup_args[256] __initdata;
  31
  32 static int md_setup_ents __initdata;
  33
  34 /*
  35  * Parse the command-line parameters given our kernel, but do not
  36  * actually try to invoke the MD device now; that is handled by
  37  * md_setup_drive after the low-level disk drivers have initialised.
  38  *
  39  * 27/11/1999: Fixed to work correctly with the 2.3 kernel (which
  40  *             assigns the task of parsing integer arguments to the
  41  *             invoked program now).  Added ability to initialise all
  42  *             the MD devices (by specifying multiple "md=" lines)
  43  *             instead of just one.  -- KTK
  44  * 18May2000: Added support for persistent-superblock arrays:
  45  *             md=n,0,factor,fault,device-list   uses RAID0 for device n
  46  *             md=n,-1,factor,fault,device-list  uses LINEAR for device n
  47  *             md=n,device-list      reads a RAID superblock from the devices
  48  *             elements in device-list are read by name_to_kdev_t so can be
  49  *             a hex number or something like /dev/hda1 /dev/sdb
  50  * 2001-06-03: Dave Cinege <dcinege@psychosis.com>
  51  *              Shifted name_to_kdev_t() and related operations to md_set_drive()
  52  *              for later execution. Rewrote section to make devfs compatible.
  53  */
  54 static int __init md_setup(char *str)
  55 {
  56         int minor, level, factor, fault, partitioned = 0;
  57         char *pername = "";
  58         char *str1;
  59         int ent;
  60
  61         if (*str == 'd') {
  62                 partitioned = 1;
  63                 str++;
  64         }
  65         if (get_option(&str, &minor) != 2) {    /* MD Number */
  66                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
  67                 return 0;
  68         }
  69         str1 = str;
  70         for (ent=0 ; ent< md_setup_ents ; ent++)
  71                 if (md_setup_args[ent].minor == minor &&
  72                     md_setup_args[ent].partitioned == partitioned) {
  73                         printk(KERN_WARNING "md: md=%s%d, Specified more than once. "
  74                                "Replacing previous definition.\n", partitioned?"d":"", minor);
  75                         break;
  76                 }
  77         if (ent >= ARRAY_SIZE(md_setup_args)) {
  78                 printk(KERN_WARNING "md: md=%s%d - too many md initialisations\n", partitioned?"d":"", minor);
  79                 return 0;
  80         }
  81         if (ent >= md_setup_ents)
  82                 md_setup_ents++;
  83         switch (get_option(&str, &level)) {     /* RAID level */
  84         case 2: /* could be 0 or -1.. */
  85                 if (level == 0 || level == LEVEL_LINEAR) {
  86                         if (get_option(&str, &factor) != 2 ||   /* Chunk Size */
  87                                         get_option(&str, &fault) != 2) {
  88                                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
  89                                 return 0;
  90                         }
  91                         md_setup_args[ent].level = level;
  92                         md_setup_args[ent].chunk = 1 << (factor+12);
  93                         if (level ==  LEVEL_LINEAR)
  94                                 pername = "linear";
  95                         else
  96                                 pername = "raid0";
  97                         break;
  98                 }
  99                 /* FALL THROUGH */
 100         case 1: /* the first device is numeric */
 101                 str = str1;
 102                 /* FALL THROUGH */
 103         case 0:
 104                 md_setup_args[ent].level = LEVEL_NONE;
 105                 pername="super-block";
 106         }
 107
 108         printk(KERN_INFO "md: Will configure md%d (%s) from %s, below.\n",
 109                 minor, pername, str);
 110         md_setup_args[ent].device_names = str;
 111         md_setup_args[ent].partitioned = partitioned;
 112         md_setup_args[ent].minor = minor;
 113
 114         return 1;
 115 }
 116
 117 static void __init md_setup_drive(void)
 118 {
 119         int minor, i, ent, partitioned;
 120         dev_t dev;
 121         dev_t devices[MD_SB_DISKS+1];
 122
 123         for (ent = 0; ent < md_setup_ents ; ent++) {
 124                 int fd;
 125                 int err = 0;
 126                 char *devname;
 127                 mdu_disk_info_t dinfo;
 128                 char name[16];
 129
 130                 minor = md_setup_args[ent].minor;
 131                 partitioned = md_setup_args[ent].partitioned;
 132                 devname = md_setup_args[ent].device_names;
 133
 134                 sprintf(name, "/dev/md%s%d", partitioned?"_d":"", minor);
 135                 if (partitioned)
 136                         dev = MKDEV(mdp_major, minor << MdpMinorShift);
 137                 else
 138                         dev = MKDEV(MD_MAJOR, minor);
 139                 create_dev(name, dev);
 140                 for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) {
 141                         char *p;
 142                         char comp_name[64];
 143                         u32 rdev;
 144
 145                         p = strchr(devname, ',');
 146                         if (p)
 147                                 *p++ = 0;
 148
 149                         dev = name_to_dev_t(devname);
 150                         if (strncmp(devname, "/dev/", 5) == 0)
 151                                 devname += 5;
 152                         snprintf(comp_name, 63, "/dev/%s", devname);
 153                         rdev = bstat(comp_name);
 154                         if (rdev)
 155                                 dev = new_decode_dev(rdev);
 156                         if (!dev) {
 157                                 printk(KERN_WARNING "md: Unknown device name: %s\n", devname);
 158                                 break;
 159                         }
 160
 161                         devices[i] = dev;
 162
 163                         devname = p;
 164                 }
 165                 devices[i] = 0;
 166
 167                 if (!i)
 168                         continue;
 169
 170                 printk(KERN_INFO "md: Loading md%s%d: %s\n",
 171                         partitioned ? "_d" : "", minor,
 172                         md_setup_args[ent].device_names);
 173
 174                 fd = ksys_open(name, 0, 0);
 175                 if (fd < 0) {
 176                         printk(KERN_ERR "md: open failed - cannot start "
 177                                         "array %s\n", name);
 178                         continue;
 179                 }
 180                 if (ksys_ioctl(fd, SET_ARRAY_INFO, 0) == -EBUSY) {
 181                         printk(KERN_WARNING
 182                                "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",
 183                                minor);
 184                         ksys_close(fd);
 185                         continue;
 186                 }
 187
 188                 if (md_setup_args[ent].level != LEVEL_NONE) {
 189                         /* non-persistent */
 190                         mdu_array_info_t ainfo;
 191                         ainfo.level = md_setup_args[ent].level;
 192                         ainfo.size = 0;
 193                         ainfo.nr_disks =0;
 194                         ainfo.raid_disks =0;
 195                         while (devices[ainfo.raid_disks])
 196                                 ainfo.raid_disks++;
 197                         ainfo.md_minor =minor;
 198                         ainfo.not_persistent = 1;
 199
 200                         ainfo.state = (1 << MD_SB_CLEAN);
 201                         ainfo.layout = 0;
 202                         ainfo.chunk_size = md_setup_args[ent].chunk;
 203                         err = ksys_ioctl(fd, SET_ARRAY_INFO, (long)&ainfo);
 204                         for (i = 0; !err && i <= MD_SB_DISKS; i++) {
 205                                 dev = devices[i];
 206                                 if (!dev)
 207                                         break;
 208                                 dinfo.number = i;
 209                                 dinfo.raid_disk = i;
 210                                 dinfo.state = (1<<MD_DISK_ACTIVE)|(1<<MD_DISK_SYNC);
 211                                 dinfo.major = MAJOR(dev);
 212                                 dinfo.minor = MINOR(dev);
 213                                 err = ksys_ioctl(fd, ADD_NEW_DISK,
 214                                                  (long)&dinfo);
 215                         }
 216                 } else {
 217                         /* persistent */
 218                         for (i = 0; i <= MD_SB_DISKS; i++) {
 219                                 dev = devices[i];
 220                                 if (!dev)
 221                                         break;
 222                                 dinfo.major = MAJOR(dev);
 223                                 dinfo.minor = MINOR(dev);
 224                                 ksys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);
 225                         }
 226                 }
 227                 if (!err)
 228                         err = ksys_ioctl(fd, RUN_ARRAY, 0);
 229                 if (err)
 230                         printk(KERN_WARNING "md: starting md%d failed\n", minor);
 231                 else {
 232                         /* reread the partition table.
 233                          * I (neilb) and not sure why this is needed, but I cannot
 234                          * boot a kernel with devfs compiled in from partitioned md
 235                          * array without it
 236                          */
 237                         ksys_close(fd);
 238                         fd = ksys_open(name, 0, 0);
 239                         ksys_ioctl(fd, BLKRRPART, 0);
 240                 }
 241                 ksys_close(fd);
 242         }
 243 }
 244
 245 static int __init raid_setup(char *str)
 246 {
 247         int len, pos;
 248
 249         len = strlen(str) + 1;
 250         pos = 0;
 251
 252         while (pos < len) {
 253                 char *comma = strchr(str+pos, ',');
 254                 int wlen;
 255                 if (comma)
 256                         wlen = (comma-str)-pos;
 257                 else    wlen = (len-1)-pos;
 258
 259                 if (!strncmp(str, "noautodetect", wlen))
 260                         raid_noautodetect = 1;
 261                 if (!strncmp(str, "autodetect", wlen))
 262                         raid_noautodetect = 0;
 263                 if (strncmp(str, "partitionable", wlen)==0)
 264                         raid_autopart = 1;
 265                 if (strncmp(str, "part", wlen)==0)
 266                         raid_autopart = 1;
 267                 pos += wlen+1;
 268         }
 269         return 1;
 270 }
 271
 272 __setup("raid=", raid_setup);
 273 __setup("md=", md_setup);
 274
 275 static void __init autodetect_raid(void)
 276 {
 277         int fd;
 278
 279         /*
 280          * Since we don't want to detect and use half a raid array, we need to
 281          * wait for the known devices to complete their probing
 282          */
 283         printk(KERN_INFO "md: Waiting for all devices to be available before autodetect\n");
 284         printk(KERN_INFO "md: If you don't use raid, use raid=noautodetect\n");
 285
 286         wait_for_device_probe();
 287
 288         fd = ksys_open("/dev/md0", 0, 0);
 289         if (fd >= 0) {
 290                 ksys_ioctl(fd, RAID_AUTORUN, raid_autopart);
 291                 ksys_close(fd);
 292         }
 293 }
 294
 295 void __init md_run_setup(void)
 296 {
 297         create_dev("/dev/md0", MKDEV(MD_MAJOR, 0));
 298
 299         if (raid_noautodetect)
 300                 printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=autodetect will force)\n");
 301         else
 302                 autodetect_raid();
 303         md_setup_drive();
 304 }