x86/speculation/l1tf: Exempt zeroed PTEs from inversion
[muen/linux.git] / 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 }