1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/kernel.h> |
3 | #include <linux/blkdev.h> |
4 | #include <linux/init.h> |
5 | #include <linux/mount.h> |
6 | #include <linux/major.h> |
7 | #include <linux/delay.h> |
8 | #include <linux/init_syscalls.h> |
9 | #include <linux/raid/detect.h> |
10 | #include <linux/raid/md_u.h> |
11 | #include <linux/raid/md_p.h> |
12 | #include "md.h" |
13 | |
14 | /* |
15 | * When md (and any require personalities) are compiled into the kernel |
16 | * (not a module), arrays can be assembles are boot time using with AUTODETECT |
17 | * where specially marked partitions are registered with md_autodetect_dev(), |
18 | * and with MD_BOOT where devices to be collected are given on the boot line |
19 | * with md=..... |
20 | * The code for that is here. |
21 | */ |
22 | |
23 | #ifdef CONFIG_MD_AUTODETECT |
24 | static int __initdata raid_noautodetect; |
25 | #else |
26 | static int __initdata raid_noautodetect=1; |
27 | #endif |
28 | static int __initdata raid_autopart; |
29 | |
30 | static struct md_setup_args { |
31 | int minor; |
32 | int partitioned; |
33 | int level; |
34 | int chunk; |
35 | char *device_names; |
36 | } md_setup_args[256] __initdata; |
37 | |
38 | static int md_setup_ents __initdata; |
39 | |
40 | /* |
41 | * Parse the command-line parameters given our kernel, but do not |
42 | * actually try to invoke the MD device now; that is handled by |
43 | * md_setup_drive after the low-level disk drivers have initialised. |
44 | * |
45 | * 27/11/1999: Fixed to work correctly with the 2.3 kernel (which |
46 | * assigns the task of parsing integer arguments to the |
47 | * invoked program now). Added ability to initialise all |
48 | * the MD devices (by specifying multiple "md=" lines) |
49 | * instead of just one. -- KTK |
50 | * 18May2000: Added support for persistent-superblock arrays: |
51 | * md=n,0,factor,fault,device-list uses RAID0 for device n |
52 | * md=n,-1,factor,fault,device-list uses LINEAR for device n |
53 | * md=n,device-list reads a RAID superblock from the devices |
54 | * elements in device-list are read by name_to_kdev_t so can be |
55 | * a hex number or something like /dev/hda1 /dev/sdb |
56 | * 2001-06-03: Dave Cinege <dcinege@psychosis.com> |
57 | * Shifted name_to_kdev_t() and related operations to md_set_drive() |
58 | * for later execution. Rewrote section to make devfs compatible. |
59 | */ |
60 | static int __init md_setup(char *str) |
61 | { |
62 | int minor, level, factor, fault, partitioned = 0; |
63 | char *pername = "" ; |
64 | char *str1; |
65 | int ent; |
66 | |
67 | if (*str == 'd') { |
68 | partitioned = 1; |
69 | str++; |
70 | } |
71 | if (get_option(str: &str, pint: &minor) != 2) { /* MD Number */ |
72 | printk(KERN_WARNING "md: Too few arguments supplied to md=.\n" ); |
73 | return 0; |
74 | } |
75 | str1 = str; |
76 | for (ent=0 ; ent< md_setup_ents ; ent++) |
77 | if (md_setup_args[ent].minor == minor && |
78 | md_setup_args[ent].partitioned == partitioned) { |
79 | printk(KERN_WARNING "md: md=%s%d, Specified more than once. " |
80 | "Replacing previous definition.\n" , partitioned?"d" :"" , minor); |
81 | break; |
82 | } |
83 | if (ent >= ARRAY_SIZE(md_setup_args)) { |
84 | printk(KERN_WARNING "md: md=%s%d - too many md initialisations\n" , partitioned?"d" :"" , minor); |
85 | return 0; |
86 | } |
87 | if (ent >= md_setup_ents) |
88 | md_setup_ents++; |
89 | switch (get_option(str: &str, pint: &level)) { /* RAID level */ |
90 | case 2: /* could be 0 or -1.. */ |
91 | if (level == 0 || level == LEVEL_LINEAR) { |
92 | if (get_option(str: &str, pint: &factor) != 2 || /* Chunk Size */ |
93 | get_option(str: &str, pint: &fault) != 2) { |
94 | printk(KERN_WARNING "md: Too few arguments supplied to md=.\n" ); |
95 | return 0; |
96 | } |
97 | md_setup_args[ent].level = level; |
98 | md_setup_args[ent].chunk = 1 << (factor+12); |
99 | if (level == LEVEL_LINEAR) |
100 | pername = "linear" ; |
101 | else |
102 | pername = "raid0" ; |
103 | break; |
104 | } |
105 | fallthrough; |
106 | case 1: /* the first device is numeric */ |
107 | str = str1; |
108 | fallthrough; |
109 | case 0: |
110 | md_setup_args[ent].level = LEVEL_NONE; |
111 | pername="super-block" ; |
112 | } |
113 | |
114 | printk(KERN_INFO "md: Will configure md%d (%s) from %s, below.\n" , |
115 | minor, pername, str); |
116 | md_setup_args[ent].device_names = str; |
117 | md_setup_args[ent].partitioned = partitioned; |
118 | md_setup_args[ent].minor = minor; |
119 | |
120 | return 1; |
121 | } |
122 | |
123 | static void __init md_setup_drive(struct md_setup_args *args) |
124 | { |
125 | char *devname = args->device_names; |
126 | dev_t devices[MD_SB_DISKS + 1], mdev; |
127 | struct mdu_array_info_s ainfo = { }; |
128 | struct mddev *mddev; |
129 | int err = 0, i; |
130 | char name[16]; |
131 | |
132 | if (args->partitioned) { |
133 | mdev = MKDEV(mdp_major, args->minor << MdpMinorShift); |
134 | sprintf(buf: name, fmt: "md_d%d" , args->minor); |
135 | } else { |
136 | mdev = MKDEV(MD_MAJOR, args->minor); |
137 | sprintf(buf: name, fmt: "md%d" , args->minor); |
138 | } |
139 | |
140 | for (i = 0; i < MD_SB_DISKS && devname != NULL; i++) { |
141 | struct kstat stat; |
142 | char *p; |
143 | char comp_name[64]; |
144 | dev_t dev; |
145 | |
146 | p = strchr(devname, ','); |
147 | if (p) |
148 | *p++ = 0; |
149 | |
150 | if (early_lookup_bdev(pathname: devname, dev: &dev)) |
151 | dev = 0; |
152 | if (strncmp(devname, "/dev/" , 5) == 0) |
153 | devname += 5; |
154 | snprintf(buf: comp_name, size: 63, fmt: "/dev/%s" , devname); |
155 | if (init_stat(filename: comp_name, stat: &stat, flags: 0) == 0 && S_ISBLK(stat.mode)) |
156 | dev = new_decode_dev(dev: stat.rdev); |
157 | if (!dev) { |
158 | pr_warn("md: Unknown device name: %s\n" , devname); |
159 | break; |
160 | } |
161 | |
162 | devices[i] = dev; |
163 | devname = p; |
164 | } |
165 | devices[i] = 0; |
166 | |
167 | if (!i) |
168 | return; |
169 | |
170 | pr_info("md: Loading %s: %s\n" , name, args->device_names); |
171 | |
172 | mddev = md_alloc(dev: mdev, name); |
173 | if (IS_ERR(ptr: mddev)) { |
174 | pr_err("md: md_alloc failed - cannot start array %s\n" , name); |
175 | return; |
176 | } |
177 | |
178 | err = mddev_suspend_and_lock(mddev); |
179 | if (err) { |
180 | pr_err("md: failed to lock array %s\n" , name); |
181 | goto out_mddev_put; |
182 | } |
183 | |
184 | if (!list_empty(head: &mddev->disks) || mddev->raid_disks) { |
185 | pr_warn("md: Ignoring %s, already autodetected. (Use raid=noautodetect)\n" , |
186 | name); |
187 | goto out_unlock; |
188 | } |
189 | |
190 | if (args->level != LEVEL_NONE) { |
191 | /* non-persistent */ |
192 | ainfo.level = args->level; |
193 | ainfo.md_minor = args->minor; |
194 | ainfo.not_persistent = 1; |
195 | ainfo.state = (1 << MD_SB_CLEAN); |
196 | ainfo.chunk_size = args->chunk; |
197 | while (devices[ainfo.raid_disks]) |
198 | ainfo.raid_disks++; |
199 | } |
200 | |
201 | err = md_set_array_info(mddev, info: &ainfo); |
202 | |
203 | for (i = 0; i <= MD_SB_DISKS && devices[i]; i++) { |
204 | struct mdu_disk_info_s dinfo = { |
205 | .major = MAJOR(devices[i]), |
206 | .minor = MINOR(devices[i]), |
207 | }; |
208 | |
209 | if (args->level != LEVEL_NONE) { |
210 | dinfo.number = i; |
211 | dinfo.raid_disk = i; |
212 | dinfo.state = |
213 | (1 << MD_DISK_ACTIVE) | (1 << MD_DISK_SYNC); |
214 | } |
215 | |
216 | md_add_new_disk(mddev, info: &dinfo); |
217 | } |
218 | |
219 | if (!err) |
220 | err = do_md_run(mddev); |
221 | if (err) |
222 | pr_warn("md: starting %s failed\n" , name); |
223 | out_unlock: |
224 | mddev_unlock_and_resume(mddev); |
225 | out_mddev_put: |
226 | mddev_put(mddev); |
227 | } |
228 | |
229 | static int __init raid_setup(char *str) |
230 | { |
231 | int len, pos; |
232 | |
233 | len = strlen(str) + 1; |
234 | pos = 0; |
235 | |
236 | while (pos < len) { |
237 | char *comma = strchr(str+pos, ','); |
238 | int wlen; |
239 | if (comma) |
240 | wlen = (comma-str)-pos; |
241 | else wlen = (len-1)-pos; |
242 | |
243 | if (!strncmp(str, "noautodetect" , wlen)) |
244 | raid_noautodetect = 1; |
245 | if (!strncmp(str, "autodetect" , wlen)) |
246 | raid_noautodetect = 0; |
247 | if (strncmp(str, "partitionable" , wlen)==0) |
248 | raid_autopart = 1; |
249 | if (strncmp(str, "part" , wlen)==0) |
250 | raid_autopart = 1; |
251 | pos += wlen+1; |
252 | } |
253 | return 1; |
254 | } |
255 | |
256 | __setup("raid=" , raid_setup); |
257 | __setup("md=" , md_setup); |
258 | |
259 | static void __init autodetect_raid(void) |
260 | { |
261 | /* |
262 | * Since we don't want to detect and use half a raid array, we need to |
263 | * wait for the known devices to complete their probing |
264 | */ |
265 | printk(KERN_INFO "md: Waiting for all devices to be available before autodetect\n" ); |
266 | printk(KERN_INFO "md: If you don't use raid, use raid=noautodetect\n" ); |
267 | |
268 | wait_for_device_probe(); |
269 | md_autostart_arrays(part: raid_autopart); |
270 | } |
271 | |
272 | void __init md_run_setup(void) |
273 | { |
274 | int ent; |
275 | |
276 | if (raid_noautodetect) |
277 | printk(KERN_INFO "md: Skipping autodetection of RAID arrays. (raid=autodetect will force)\n" ); |
278 | else |
279 | autodetect_raid(); |
280 | |
281 | for (ent = 0; ent < md_setup_ents; ent++) |
282 | md_setup_drive(args: &md_setup_args[ent]); |
283 | } |
284 | |