init/do_mounts_md.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Many of the syscalls used in this file expect some of the arguments
   4  * to be __user pointers not __kernel pointers.  To limit the sparse
   5  * noise, turn off sparse checking for this file.
   6  */
   7 #ifdef __CHECKER__
   8 #undef __CHECKER__
   9 #warning "Sparse checking disabled for this file"
  10 #endif
  11
  12 #include <linux/delay.h>
  13 #include <linux/raid/md_u.h>
  14 #include <linux/raid/md_p.h>
  15
  16 #include "do_mounts.h"
  17
  18 /*
  19  * When md (and any require personalities) are compiled into the kernel
  20  * (not a module), arrays can be assembles are boot time using with AUTODETECT
  21  * where specially marked partitions are registered with md_autodetect_dev(),
  22  * and with MD_BOOT where devices to be collected are given on the boot line
  23  * with md=.....
  24  * The code for that is here.
  25  */
  26
  27 #ifdef CONFIG_MD_AUTODETECT
  28 static int __initdata raid_noautodetect;
  29 #else
  30 static int __initdata raid_noautodetect=1;
  31 #endif
  32 static int __initdata raid_autopart;
  33
  34 static struct {
  35         int minor;
  36         int partitioned;
  37         int level;
  38         int chunk;
  39         char *device_names;
  40 } md_setup_args[256] __initdata;
  41
  42 static int md_setup_ents __initdata;
  43
  44 /*
  45  * Parse the command-line parameters given our kernel, but do not
  46  * actually try to invoke the MD device now; that is handled by
  47  * md_setup_drive after the low-level disk drivers have initialised.
  48  *
  49  * 27/11/1999: Fixed to work correctly with the 2.3 kernel (which
  50  *             assigns the task of parsing integer arguments to the
  51  *             invoked program now).  Added ability to initialise all
  52  *             the MD devices (by specifying multiple "md=" lines)
  53  *             instead of just one.  -- KTK
  54  * 18May2000: Added support for persistent-superblock arrays:
  55  *             md=n,0,factor,fault,device-list   uses RAID0 for device n
  56  *             md=n,-1,factor,fault,device-list  uses LINEAR for device n
  57  *             md=n,device-list      reads a RAID superblock from the devices
  58  *             elements in device-list are read by name_to_kdev_t so can be
  59  *             a hex number or something like /dev/hda1 /dev/sdb
  60  * 2001-06-03: Dave Cinege <dcinege@psychosis.com>
  61  *              Shifted name_to_kdev_t() and related operations to md_set_drive()
  62  *              for later execution. Rewrote section to make devfs compatible.
  63  */
  64 static int __init md_setup(char *str)
  65 {
  66         int minor, level, factor, fault, partitioned = 0;
  67         char *pername = "";
  68         char *str1;
  69         int ent;
  70
  71         if (*str == 'd') {
  72                 partitioned = 1;
  73                 str++;
  74         }
  75         if (get_option(&str, &minor) != 2) {    /* MD Number */
  76                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
  77                 return 0;
  78         }
  79         str1 = str;
  80         for (ent=0 ; ent< md_setup_ents ; ent++)
  81                 if (md_setup_args[ent].minor == minor &&
  82                     md_setup_args[ent].partitioned == partitioned) {
  83                         printk(KERN_WARNING "md: md=%s%d, Specified more than once. "
  84                                "Replacing previous definition.\n", partitioned?"d":"", minor);
  85                         break;
  86                 }
  87         if (ent >= ARRAY_SIZE(md_setup_args)) {
  88                 printk(KERN_WARNING "md: md=%s%d - too many md initialisations\n", partitioned?"d":"", minor);
  89                 return 0;
  90         }
  91         if (ent >= md_setup_ents)
  92                 md_setup_ents++;
  93         switch (get_option(&str, &level)) {     /* RAID level */
  94         case 2: /* could be 0 or -1.. */
  95                 if (level == 0 || level == LEVEL_LINEAR) {
  96                         if (get_option(&str, &factor) != 2 ||   /* Chunk Size */
  97                                         get_option(&str, &fault) != 2) {
  98                                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
  99                                 return 0;
 100                         }
 101                         md_setup_args[ent].level = level;
 102                         md_setup_args[ent].chunk = 1 << (factor+12);
 103                         if (level ==  LEVEL_LINEAR)
 104                                 pername = "linear";
 105                         else
 106                                 pername = "raid0";
 107                         break;
 108                 }
 109                 /* FALL THROUGH */
 110         case 1: /* the first device is numeric */
 111                 str = str1;
 112                 /* FALL THROUGH */
 113         case 0:
 114                 md_setup_args[ent].level = LEVEL_NONE;
 115                 pername="super-block";
 116         }
 117
 118         printk(KERN_INFO "md: Will configure md%d (%s) from %s, below.\n",
 119                 minor, pername, str);
 120         md_setup_args[ent].device_names = str;
 121         md_setup_args[ent].partitioned = partitioned;
 122         md_setup_args[ent].minor = minor;
 123
 124         return 1;
 125 }
 126
 127 static void __init md_setup_drive(void)
 128 {
 129         int minor, i, ent, partitioned;
 130         dev_t dev;
 131         dev_t devices[MD_SB_DISKS+1];
 132
 133         for (ent = 0; ent < md_setup_ents ; ent++) {
 134                 int fd;
 135                 int err = 0;
 136                 char *devname;
 137                 mdu_disk_info_t dinfo;
 138                 char name[16];
 139
 140                 minor = md_setup_args[ent].minor;
 141                 partitioned = md_setup_args[ent].partitioned;
 142                 devname = md_setup_args[ent].device_names;
 143
 144                 sprintf(name, "/dev/md%s%d", partitioned?"_d":"", minor);
 145                 if (partitioned)
 146                         dev = MKDEV(mdp_major, minor << MdpMinorShift);
 147                 else
 148                         dev = MKDEV(MD_MAJOR, minor);
 149                 create_dev(name, dev);
 150                 for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) {
 151                         char *p;
 152                         char comp_name[64];
 153                         u32 rdev;
 154
 155                         p = strchr(devname, ',');
 156                         if (p)
 157                                 *p++ = 0;
 158
 159                         dev = name_to_dev_t(devname);
 160                         if (strncmp(devname, "/dev/", 5) == 0)
 161                                 devname += 5;
 162                         snprintf(comp_name, 63, "/dev/%s", devname);
 163                         rdev = bstat(comp_name);
 164                         if (rdev)
 165                                 dev = new_decode_dev(rdev);
 166                         if (!dev) {
 167                                 printk(KERN_WARNING "md: Unknown device name: %s\n", devname);
 168                                 break;
 169                         }
 170
 171                         devices[i] = dev;
 172
 173                         devname = p;
 174                 }
 175                 devices[i] = 0;
 176
 177                 if (!i)
 178                         continue;
 179
 180                 printk(KERN_INFO "md: Loading md%s%d: %s\n",
 181                         partitioned ? "_d" : "", minor,
 182                         md_setup_args[ent].device_names);
 183
 184                 fd = ksys_open(name, 0, 0);
 185                 if (fd < 0) {
 186                         printk(KERN_ERR "md: open failed - cannot start "
 187                                         "array %s\n", name);
 188                         continue;
 189                 }
 190                 if (ksys_ioctl(fd, SET_ARRAY_INFO, 0) == -EBUSY) {
 191                         printk(KERN_WARNING
 192                                "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",
 193                                minor);
 194                         ksys_close(fd);
 195                         continue;
 196                 }
 197
 198                 if (md_setup_args[ent].level != LEVEL_NONE) {
 199                         /* non-persistent */
 200                         mdu_array_info_t ainfo;
 201                         ainfo.level = md_setup_args[ent].level;
 202                         ainfo.size = 0;
 203                         ainfo.nr_disks =0;
 204                         ainfo.raid_disks =0;
 205                         while (devices[ainfo.raid_disks])
 206                                 ainfo.raid_disks++;
 207                         ainfo.md_minor =minor;
 208                         ainfo.not_persistent = 1;
 209
 210                         ainfo.state = (1 << MD_SB_CLEAN);
 211                         ainfo.layout = 0;
 212                         ainfo.chunk_size = md_setup_args[ent].chunk;
 213                         err = ksys_ioctl(fd, SET_ARRAY_INFO, (long)&ainfo);
 214                         for (i = 0; !err && i <= MD_SB_DISKS; i++) {
 215                                 dev = devices[i];
 216                                 if (!dev)
 217                                         break;
 218                                 dinfo.number = i;
 219                                 dinfo.raid_disk = i;
 220                                 dinfo.state = (1<<MD_DISK_ACTIVE)|(1<<MD_DISK_SYNC);
 221                                 dinfo.major = MAJOR(dev);
 222                                 dinfo.minor = MINOR(dev);
 223                                 err = ksys_ioctl(fd, ADD_NEW_DISK,
 224                                                  (long)&dinfo);
 225                         }
 226                 } else {
 227                         /* persistent */
 228                         for (i = 0; i <= MD_SB_DISKS; i++) {
 229                                 dev = devices[i];
 230                                 if (!dev)
 231                                         break;
 232                                 dinfo.major = MAJOR(dev);
 233                                 dinfo.minor = MINOR(dev);
 234                                 ksys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);
 235                         }
 236                 }
 237                 if (!err)
 238                         err = ksys_ioctl(fd, RUN_ARRAY, 0);
 239                 if (err)
 240                         printk(KERN_WARNING "md: starting md%d failed\n", minor);
 241                 else {
 242                         /* reread the partition table.
 243                          * I (neilb) and not sure why this is needed, but I cannot
 244                          * boot a kernel with devfs compiled in from partitioned md
 245                          * array without it
 246                          */
 247                         ksys_close(fd);
 248                         fd = ksys_open(name, 0, 0);
 249                         ksys_ioctl(fd, BLKRRPART, 0);
 250                 }
 251                 ksys_close(fd);
 252         }
 253 }
 254
 255 static int __init raid_setup(char *str)
 256 {
 257         int len, pos;
 258
 259         len = strlen(str) + 1;
 260         pos = 0;
 261
 262         while (pos < len) {
 263                 char *comma = strchr(str+pos, ',');
 264                 int wlen;
 265                 if (comma)
 266                         wlen = (comma-str)-pos;
 267                 else    wlen = (len-1)-pos;
 268
 269                 if (!strncmp(str, "noautodetect", wlen))
 270                         raid_noautodetect = 1;
 271                 if (!strncmp(str, "autodetect", wlen))
 272                         raid_noautodetect = 0;
 273                 if (strncmp(str, "partitionable", wlen)==0)
 274                         raid_autopart = 1;
 275                 if (strncmp(str, "part", wlen)==0)
 276                         raid_autopart = 1;
 277                 pos += wlen+1;
 278         }
 279         return 1;
 280 }
 281
 282 __setup("raid=", raid_setup);
 283 __setup("md=", md_setup);
 284
 285 static void __init autodetect_raid(void)
 286 {
 287         int fd;
 288
 289         /*
 290          * Since we don't want to detect and use half a raid array, we need to
 291          * wait for the known devices to complete their probing
 292          */
 293         printk(KERN_INFO "md: Waiting for all devices to be available before autodetect\n");
 294         printk(KERN_INFO "md: If you don't use raid, use raid=noautodetect\n");
 295
 296         wait_for_device_probe();
 297
 298         fd = ksys_open("/dev/md0", 0, 0);
 299         if (fd >= 0) {
 300                 ksys_ioctl(fd, RAID_AUTORUN, raid_autopart);
 301                 ksys_close(fd);
 302         }
 303 }
 304
 305 void __init md_run_setup(void)
 306 {
 307         create_dev("/dev/md0", MKDEV(MD_MAJOR, 0));
 308
 309         if (raid_noautodetect)
 310                 printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=autodetect will force)\n");
 311         else
 312                 autodetect_raid();
 313         md_setup_drive();
 314 }