[PATCH] aio: ring wrapping simplification
[linux-2.6] / init / do_mounts_md.c
1
2 #include <linux/raid/md.h>
3
4 #include "do_mounts.h"
5
6 /*
7  * When md (and any require personalities) are compiled into the kernel
8  * (not a module), arrays can be assembles are boot time using with AUTODETECT
9  * where specially marked partitions are registered with md_autodetect_dev(),
10  * and with MD_BOOT where devices to be collected are given on the boot line
11  * with md=.....
12  * The code for that is here.
13  */
14
15 static int __initdata raid_noautodetect, raid_autopart;
16
17 static struct {
18         int minor;
19         int partitioned;
20         int pers;
21         int chunk;
22         char *device_names;
23 } md_setup_args[MAX_MD_DEVS] __initdata;
24
25 static int md_setup_ents __initdata;
26
27 extern int mdp_major;
28 /*
29  * Parse the command-line parameters given our kernel, but do not
30  * actually try to invoke the MD device now; that is handled by
31  * md_setup_drive after the low-level disk drivers have initialised.
32  *
33  * 27/11/1999: Fixed to work correctly with the 2.3 kernel (which
34  *             assigns the task of parsing integer arguments to the
35  *             invoked program now).  Added ability to initialise all
36  *             the MD devices (by specifying multiple "md=" lines)
37  *             instead of just one.  -- KTK
38  * 18May2000: Added support for persistent-superblock arrays:
39  *             md=n,0,factor,fault,device-list   uses RAID0 for device n
40  *             md=n,-1,factor,fault,device-list  uses LINEAR for device n
41  *             md=n,device-list      reads a RAID superblock from the devices
42  *             elements in device-list are read by name_to_kdev_t so can be
43  *             a hex number or something like /dev/hda1 /dev/sdb
44  * 2001-06-03: Dave Cinege <dcinege@psychosis.com>
45  *              Shifted name_to_kdev_t() and related operations to md_set_drive()
46  *              for later execution. Rewrote section to make devfs compatible.
47  */
48 static int __init md_setup(char *str)
49 {
50         int minor, level, factor, fault, pers, partitioned = 0;
51         char *pername = "";
52         char *str1;
53         int ent;
54
55         if (*str == 'd') {
56                 partitioned = 1;
57                 str++;
58         }
59         if (get_option(&str, &minor) != 2) {    /* MD Number */
60                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
61                 return 0;
62         }
63         str1 = str;
64         if (minor >= MAX_MD_DEVS) {
65                 printk(KERN_WARNING "md: md=%d, Minor device number too high.\n", minor);
66                 return 0;
67         }
68         for (ent=0 ; ent< md_setup_ents ; ent++)
69                 if (md_setup_args[ent].minor == minor &&
70                     md_setup_args[ent].partitioned == partitioned) {
71                         printk(KERN_WARNING "md: md=%s%d, Specified more than once. "
72                                "Replacing previous definition.\n", partitioned?"d":"", minor);
73                         break;
74                 }
75         if (ent >= MAX_MD_DEVS) {
76                 printk(KERN_WARNING "md: md=%s%d - too many md initialisations\n", partitioned?"d":"", minor);
77                 return 0;
78         }
79         if (ent >= md_setup_ents)
80                 md_setup_ents++;
81         switch (get_option(&str, &level)) {     /* RAID Personality */
82         case 2: /* could be 0 or -1.. */
83                 if (level == 0 || level == LEVEL_LINEAR) {
84                         if (get_option(&str, &factor) != 2 ||   /* Chunk Size */
85                                         get_option(&str, &fault) != 2) {
86                                 printk(KERN_WARNING "md: Too few arguments supplied to md=.\n");
87                                 return 0;
88                         }
89                         md_setup_args[ent].pers = level;
90                         md_setup_args[ent].chunk = 1 << (factor+12);
91                         if (level ==  LEVEL_LINEAR) {
92                                 pers = LINEAR;
93                                 pername = "linear";
94                         } else {
95                                 pers = RAID0;
96                                 pername = "raid0";
97                         }
98                         md_setup_args[ent].pers = pers;
99                         break;
100                 }
101                 /* FALL THROUGH */
102         case 1: /* the first device is numeric */
103                 str = str1;
104                 /* FALL THROUGH */
105         case 0:
106                 md_setup_args[ent].pers = 0;
107                 pername="super-block";
108         }
109
110         printk(KERN_INFO "md: Will configure md%d (%s) from %s, below.\n",
111                 minor, pername, str);
112         md_setup_args[ent].device_names = str;
113         md_setup_args[ent].partitioned = partitioned;
114         md_setup_args[ent].minor = minor;
115
116         return 1;
117 }
118
119 #define MdpMinorShift 6
120
121 static void __init md_setup_drive(void)
122 {
123         int minor, i, ent, partitioned;
124         dev_t dev;
125         dev_t devices[MD_SB_DISKS+1];
126
127         for (ent = 0; ent < md_setup_ents ; ent++) {
128                 int fd;
129                 int err = 0;
130                 char *devname;
131                 mdu_disk_info_t dinfo;
132                 char name[16], devfs_name[16];
133
134                 minor = md_setup_args[ent].minor;
135                 partitioned = md_setup_args[ent].partitioned;
136                 devname = md_setup_args[ent].device_names;
137
138                 sprintf(name, "/dev/md%s%d", partitioned?"_d":"", minor);
139                 sprintf(devfs_name, "/dev/md/%s%d", partitioned?"d":"", minor);
140                 if (partitioned)
141                         dev = MKDEV(mdp_major, minor << MdpMinorShift);
142                 else
143                         dev = MKDEV(MD_MAJOR, minor);
144                 create_dev(name, dev, devfs_name);
145                 for (i = 0; i < MD_SB_DISKS && devname != 0; i++) {
146                         char *p;
147                         char comp_name[64];
148                         u32 rdev;
149
150                         p = strchr(devname, ',');
151                         if (p)
152                                 *p++ = 0;
153
154                         dev = name_to_dev_t(devname);
155                         if (strncmp(devname, "/dev/", 5) == 0)
156                                 devname += 5;
157                         snprintf(comp_name, 63, "/dev/%s", devname);
158                         rdev = bstat(comp_name);
159                         if (rdev)
160                                 dev = new_decode_dev(rdev);
161                         if (!dev) {
162                                 printk(KERN_WARNING "md: Unknown device name: %s\n", devname);
163                                 break;
164                         }
165
166                         devices[i] = dev;
167
168                         devname = p;
169                 }
170                 devices[i] = 0;
171
172                 if (!i)
173                         continue;
174
175                 printk(KERN_INFO "md: Loading md%s%d: %s\n",
176                         partitioned ? "_d" : "", minor,
177                         md_setup_args[ent].device_names);
178
179                 fd = sys_open(name, 0, 0);
180                 if (fd < 0) {
181                         printk(KERN_ERR "md: open failed - cannot start "
182                                         "array %s\n", name);
183                         continue;
184                 }
185                 if (sys_ioctl(fd, SET_ARRAY_INFO, 0) == -EBUSY) {
186                         printk(KERN_WARNING
187                                "md: Ignoring md=%d, already autodetected. (Use raid=noautodetect)\n",
188                                minor);
189                         sys_close(fd);
190                         continue;
191                 }
192
193                 if (md_setup_args[ent].pers) {
194                         /* non-persistent */
195                         mdu_array_info_t ainfo;
196                         ainfo.level = pers_to_level(md_setup_args[ent].pers);
197                         ainfo.size = 0;
198                         ainfo.nr_disks =0;
199                         ainfo.raid_disks =0;
200                         while (devices[ainfo.raid_disks])
201                                 ainfo.raid_disks++;
202                         ainfo.md_minor =minor;
203                         ainfo.not_persistent = 1;
204
205                         ainfo.state = (1 << MD_SB_CLEAN);
206                         ainfo.layout = 0;
207                         ainfo.chunk_size = md_setup_args[ent].chunk;
208                         err = sys_ioctl(fd, SET_ARRAY_INFO, (long)&ainfo);
209                         for (i = 0; !err && i <= MD_SB_DISKS; i++) {
210                                 dev = devices[i];
211                                 if (!dev)
212                                         break;
213                                 dinfo.number = i;
214                                 dinfo.raid_disk = i;
215                                 dinfo.state = (1<<MD_DISK_ACTIVE)|(1<<MD_DISK_SYNC);
216                                 dinfo.major = MAJOR(dev);
217                                 dinfo.minor = MINOR(dev);
218                                 err = sys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);
219                         }
220                 } else {
221                         /* persistent */
222                         for (i = 0; i <= MD_SB_DISKS; i++) {
223                                 dev = devices[i];
224                                 if (!dev)
225                                         break;
226                                 dinfo.major = MAJOR(dev);
227                                 dinfo.minor = MINOR(dev);
228                                 sys_ioctl(fd, ADD_NEW_DISK, (long)&dinfo);
229                         }
230                 }
231                 if (!err)
232                         err = sys_ioctl(fd, RUN_ARRAY, 0);
233                 if (err)
234                         printk(KERN_WARNING "md: starting md%d failed\n", minor);
235                 else {
236                         /* reread the partition table.
237                          * I (neilb) and not sure why this is needed, but I cannot
238                          * boot a kernel with devfs compiled in from partitioned md
239                          * array without it
240                          */
241                         sys_close(fd);
242                         fd = sys_open(name, 0, 0);
243                         sys_ioctl(fd, BLKRRPART, 0);
244                 }
245                 sys_close(fd);
246         }
247 }
248
249 static int __init raid_setup(char *str)
250 {
251         int len, pos;
252
253         len = strlen(str) + 1;
254         pos = 0;
255
256         while (pos < len) {
257                 char *comma = strchr(str+pos, ',');
258                 int wlen;
259                 if (comma)
260                         wlen = (comma-str)-pos;
261                 else    wlen = (len-1)-pos;
262
263                 if (!strncmp(str, "noautodetect", wlen))
264                         raid_noautodetect = 1;
265                 if (strncmp(str, "partitionable", wlen)==0)
266                         raid_autopart = 1;
267                 if (strncmp(str, "part", wlen)==0)
268                         raid_autopart = 1;
269                 pos += wlen+1;
270         }
271         return 1;
272 }
273
274 __setup("raid=", raid_setup);
275 __setup("md=", md_setup);
276
277 void __init md_run_setup(void)
278 {
279         create_dev("/dev/md0", MKDEV(MD_MAJOR, 0), "md/0");
280         if (raid_noautodetect)
281                 printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=noautodetect)\n");
282         else {
283                 int fd = sys_open("/dev/md0", 0, 0);
284                 if (fd >= 0) {
285                         sys_ioctl(fd, RAID_AUTORUN, raid_autopart);
286                         sys_close(fd);
287                 }
288         }
289         md_setup_drive();
290 }