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Commit | Line | Data |
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6c29256c | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
3 | * Licensed under the GPL | |
4 | */ | |
5 | ||
6 | /* 2001-09-28...2002-04-17 | |
7 | * Partition stuff by James_McMechan@hotmail.com | |
8 | * old style ubd by setting UBD_SHIFT to 0 | |
9 | * 2002-09-27...2002-10-18 massive tinkering for 2.5 | |
10 | * partitions have changed in 2.5 | |
11 | * 2003-01-29 more tinkering for 2.5.59-1 | |
12 | * This should now address the sysfs problems and has | |
13 | * the symlink for devfs to allow for booting with | |
14 | * the common /dev/ubd/discX/... names rather than | |
15 | * only /dev/ubdN/discN this version also has lots of | |
16 | * clean ups preparing for ubd-many. | |
17 | * James McMechan | |
18 | */ | |
19 | ||
1da177e4 LT |
20 | #define UBD_SHIFT 4 |
21 | ||
e16f5350 | 22 | #include "linux/kernel.h" |
1da177e4 LT |
23 | #include "linux/module.h" |
24 | #include "linux/blkdev.h" | |
73855e13 | 25 | #include "linux/ata.h" |
1da177e4 LT |
26 | #include "linux/hdreg.h" |
27 | #include "linux/init.h" | |
1da177e4 LT |
28 | #include "linux/cdrom.h" |
29 | #include "linux/proc_fs.h" | |
6613c5e8 | 30 | #include "linux/seq_file.h" |
1da177e4 LT |
31 | #include "linux/ctype.h" |
32 | #include "linux/capability.h" | |
33 | #include "linux/mm.h" | |
5a0e3ad6 | 34 | #include "linux/slab.h" |
1da177e4 | 35 | #include "linux/vmalloc.h" |
9a181c58 | 36 | #include "linux/mutex.h" |
1da177e4 LT |
37 | #include "linux/blkpg.h" |
38 | #include "linux/genhd.h" | |
39 | #include "linux/spinlock.h" | |
d052d1be | 40 | #include "linux/platform_device.h" |
23464ffa | 41 | #include "linux/scatterlist.h" |
1da177e4 LT |
42 | #include "asm/segment.h" |
43 | #include "asm/uaccess.h" | |
44 | #include "asm/irq.h" | |
45 | #include "asm/types.h" | |
46 | #include "asm/tlbflush.h" | |
1da177e4 LT |
47 | #include "mem_user.h" |
48 | #include "kern_util.h" | |
1da177e4 LT |
49 | #include "mconsole_kern.h" |
50 | #include "init.h" | |
51 | #include "irq_user.h" | |
52 | #include "irq_kern.h" | |
53 | #include "ubd_user.h" | |
1da177e4 LT |
54 | #include "os.h" |
55 | #include "mem.h" | |
1da177e4 LT |
56 | #include "cow.h" |
57 | ||
7b9014c1 | 58 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
59 | |
60 | struct io_thread_req { | |
62f96cb0 | 61 | struct request *req; |
91acb21f | 62 | enum ubd_req op; |
1da177e4 LT |
63 | int fds[2]; |
64 | unsigned long offsets[2]; | |
65 | unsigned long long offset; | |
66 | unsigned long length; | |
67 | char *buffer; | |
68 | int sectorsize; | |
91acb21f JD |
69 | unsigned long sector_mask; |
70 | unsigned long long cow_offset; | |
71 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
72 | int error; |
73 | }; | |
74 | ||
91acb21f | 75 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
76 | { |
77 | __u64 n; | |
78 | int bits, off; | |
79 | ||
91acb21f | 80 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
81 | n = bit / bits; |
82 | off = bit % bits; | |
dc764e50 | 83 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
84 | } |
85 | ||
91acb21f | 86 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
87 | { |
88 | __u64 n; | |
89 | int bits, off; | |
90 | ||
91acb21f | 91 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
92 | n = bit / bits; |
93 | off = bit % bits; | |
91acb21f | 94 | data[n] |= (1 << off); |
1da177e4 LT |
95 | } |
96 | /*End stuff from ubd_user.h*/ | |
97 | ||
98 | #define DRIVER_NAME "uml-blkdev" | |
99 | ||
d7fb2c38 | 100 | static DEFINE_MUTEX(ubd_lock); |
9a181c58 | 101 | static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ |
1da177e4 | 102 | |
a625c998 AV |
103 | static int ubd_open(struct block_device *bdev, fmode_t mode); |
104 | static int ubd_release(struct gendisk *disk, fmode_t mode); | |
105 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, | |
1da177e4 | 106 | unsigned int cmd, unsigned long arg); |
a885c8c4 | 107 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 108 | |
97d88ac8 | 109 | #define MAX_DEV (16) |
1da177e4 | 110 | |
83d5cde4 | 111 | static const struct block_device_operations ubd_blops = { |
1da177e4 | 112 | .owner = THIS_MODULE, |
a625c998 AV |
113 | .open = ubd_open, |
114 | .release = ubd_release, | |
115 | .ioctl = ubd_ioctl, | |
a885c8c4 | 116 | .getgeo = ubd_getgeo, |
1da177e4 LT |
117 | }; |
118 | ||
1da177e4 | 119 | /* Protected by ubd_lock */ |
792dd4fc | 120 | static int fake_major = UBD_MAJOR; |
1da177e4 LT |
121 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
122 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 123 | |
1da177e4 LT |
124 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
125 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
126 | .cl = 1 }) | |
127 | #else | |
128 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
129 | .cl = 1 }) | |
130 | #endif | |
1da177e4 LT |
131 | static struct openflags global_openflags = OPEN_FLAGS; |
132 | ||
133 | struct cow { | |
2a9d32f6 | 134 | /* backing file name */ |
1da177e4 | 135 | char *file; |
2a9d32f6 | 136 | /* backing file fd */ |
1da177e4 LT |
137 | int fd; |
138 | unsigned long *bitmap; | |
139 | unsigned long bitmap_len; | |
140 | int bitmap_offset; | |
dc764e50 | 141 | int data_offset; |
1da177e4 LT |
142 | }; |
143 | ||
a0044bdf JD |
144 | #define MAX_SG 64 |
145 | ||
1da177e4 | 146 | struct ubd { |
a0044bdf | 147 | struct list_head restart; |
2a9d32f6 PBG |
148 | /* name (and fd, below) of the file opened for writing, either the |
149 | * backing or the cow file. */ | |
1da177e4 LT |
150 | char *file; |
151 | int count; | |
152 | int fd; | |
153 | __u64 size; | |
154 | struct openflags boot_openflags; | |
155 | struct openflags openflags; | |
84e945e3 PBG |
156 | unsigned shared:1; |
157 | unsigned no_cow:1; | |
1da177e4 LT |
158 | struct cow cow; |
159 | struct platform_device pdev; | |
62f96cb0 JD |
160 | struct request_queue *queue; |
161 | spinlock_t lock; | |
a0044bdf JD |
162 | struct scatterlist sg[MAX_SG]; |
163 | struct request *request; | |
164 | int start_sg, end_sg; | |
47526903 | 165 | sector_t rq_pos; |
1da177e4 LT |
166 | }; |
167 | ||
168 | #define DEFAULT_COW { \ | |
169 | .file = NULL, \ | |
dc764e50 JD |
170 | .fd = -1, \ |
171 | .bitmap = NULL, \ | |
1da177e4 | 172 | .bitmap_offset = 0, \ |
dc764e50 | 173 | .data_offset = 0, \ |
1da177e4 LT |
174 | } |
175 | ||
176 | #define DEFAULT_UBD { \ | |
177 | .file = NULL, \ | |
178 | .count = 0, \ | |
179 | .fd = -1, \ | |
180 | .size = -1, \ | |
181 | .boot_openflags = OPEN_FLAGS, \ | |
182 | .openflags = OPEN_FLAGS, \ | |
dc764e50 | 183 | .no_cow = 0, \ |
6c29256c | 184 | .shared = 0, \ |
dc764e50 | 185 | .cow = DEFAULT_COW, \ |
22e65004 | 186 | .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ |
a0044bdf JD |
187 | .request = NULL, \ |
188 | .start_sg = 0, \ | |
189 | .end_sg = 0, \ | |
47526903 | 190 | .rq_pos = 0, \ |
1da177e4 LT |
191 | } |
192 | ||
b8831a1d | 193 | /* Protected by ubd_lock */ |
5dc62b1b | 194 | static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; |
1da177e4 | 195 | |
1da177e4 LT |
196 | /* Only changed by fake_ide_setup which is a setup */ |
197 | static int fake_ide = 0; | |
198 | static struct proc_dir_entry *proc_ide_root = NULL; | |
199 | static struct proc_dir_entry *proc_ide = NULL; | |
200 | ||
201 | static void make_proc_ide(void) | |
202 | { | |
203 | proc_ide_root = proc_mkdir("ide", NULL); | |
204 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
205 | } | |
206 | ||
6613c5e8 | 207 | static int fake_ide_media_proc_show(struct seq_file *m, void *v) |
1da177e4 | 208 | { |
6613c5e8 AD |
209 | seq_puts(m, "disk\n"); |
210 | return 0; | |
211 | } | |
212 | ||
213 | static int fake_ide_media_proc_open(struct inode *inode, struct file *file) | |
214 | { | |
215 | return single_open(file, fake_ide_media_proc_show, NULL); | |
1da177e4 LT |
216 | } |
217 | ||
6613c5e8 AD |
218 | static const struct file_operations fake_ide_media_proc_fops = { |
219 | .owner = THIS_MODULE, | |
220 | .open = fake_ide_media_proc_open, | |
221 | .read = seq_read, | |
222 | .llseek = seq_lseek, | |
223 | .release = single_release, | |
224 | }; | |
225 | ||
c0a9290e | 226 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
227 | { |
228 | struct proc_dir_entry *dir, *ent; | |
229 | char name[64]; | |
230 | ||
231 | if(proc_ide_root == NULL) make_proc_ide(); | |
232 | ||
233 | dir = proc_mkdir(dev_name, proc_ide); | |
234 | if(!dir) return; | |
235 | ||
6613c5e8 | 236 | ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); |
1da177e4 | 237 | if(!ent) return; |
c0a9290e | 238 | snprintf(name, sizeof(name), "ide0/%s", dev_name); |
1da177e4 LT |
239 | proc_symlink(dev_name, proc_ide_root, name); |
240 | } | |
241 | ||
242 | static int fake_ide_setup(char *str) | |
243 | { | |
244 | fake_ide = 1; | |
dc764e50 | 245 | return 1; |
1da177e4 LT |
246 | } |
247 | ||
248 | __setup("fake_ide", fake_ide_setup); | |
249 | ||
250 | __uml_help(fake_ide_setup, | |
251 | "fake_ide\n" | |
252 | " Create ide0 entries that map onto ubd devices.\n\n" | |
253 | ); | |
254 | ||
255 | static int parse_unit(char **ptr) | |
256 | { | |
257 | char *str = *ptr, *end; | |
258 | int n = -1; | |
259 | ||
260 | if(isdigit(*str)) { | |
261 | n = simple_strtoul(str, &end, 0); | |
262 | if(end == str) | |
dc764e50 | 263 | return -1; |
1da177e4 LT |
264 | *ptr = end; |
265 | } | |
97d88ac8 | 266 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
267 | n = *str - 'a'; |
268 | str++; | |
269 | *ptr = str; | |
270 | } | |
dc764e50 | 271 | return n; |
1da177e4 LT |
272 | } |
273 | ||
d8d7c28e PBG |
274 | /* If *index_out == -1 at exit, the passed option was a general one; |
275 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
276 | * should not be freed on exit. | |
277 | */ | |
f28169d2 | 278 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 279 | { |
7d314e34 | 280 | struct ubd *ubd_dev; |
1da177e4 LT |
281 | struct openflags flags = global_openflags; |
282 | char *backing_file; | |
b8831a1d | 283 | int n, err = 0, i; |
1da177e4 LT |
284 | |
285 | if(index_out) *index_out = -1; | |
286 | n = *str; | |
287 | if(n == '='){ | |
288 | char *end; | |
289 | int major; | |
290 | ||
291 | str++; | |
1da177e4 LT |
292 | if(!strcmp(str, "sync")){ |
293 | global_openflags = of_sync(global_openflags); | |
b8831a1d | 294 | goto out1; |
1da177e4 | 295 | } |
b8831a1d JD |
296 | |
297 | err = -EINVAL; | |
1da177e4 LT |
298 | major = simple_strtoul(str, &end, 0); |
299 | if((*end != '\0') || (end == str)){ | |
f28169d2 | 300 | *error_out = "Didn't parse major number"; |
b8831a1d | 301 | goto out1; |
1da177e4 LT |
302 | } |
303 | ||
f28169d2 | 304 | mutex_lock(&ubd_lock); |
792dd4fc | 305 | if (fake_major != UBD_MAJOR) { |
f28169d2 JD |
306 | *error_out = "Can't assign a fake major twice"; |
307 | goto out1; | |
308 | } | |
6c29256c | 309 | |
f28169d2 | 310 | fake_major = major; |
1da177e4 LT |
311 | |
312 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
313 | major); | |
f28169d2 JD |
314 | err = 0; |
315 | out1: | |
316 | mutex_unlock(&ubd_lock); | |
317 | return err; | |
1da177e4 LT |
318 | } |
319 | ||
320 | n = parse_unit(&str); | |
321 | if(n < 0){ | |
f28169d2 JD |
322 | *error_out = "Couldn't parse device number"; |
323 | return -EINVAL; | |
1da177e4 LT |
324 | } |
325 | if(n >= MAX_DEV){ | |
f28169d2 JD |
326 | *error_out = "Device number out of range"; |
327 | return 1; | |
1da177e4 LT |
328 | } |
329 | ||
f28169d2 | 330 | err = -EBUSY; |
d7fb2c38 | 331 | mutex_lock(&ubd_lock); |
1da177e4 | 332 | |
7d314e34 PBG |
333 | ubd_dev = &ubd_devs[n]; |
334 | if(ubd_dev->file != NULL){ | |
f28169d2 | 335 | *error_out = "Device is already configured"; |
1da177e4 LT |
336 | goto out; |
337 | } | |
338 | ||
339 | if (index_out) | |
340 | *index_out = n; | |
341 | ||
f28169d2 | 342 | err = -EINVAL; |
6c29256c | 343 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
344 | switch (*str) { |
345 | case 'r': | |
346 | flags.w = 0; | |
347 | break; | |
348 | case 's': | |
349 | flags.s = 1; | |
350 | break; | |
351 | case 'd': | |
7d314e34 | 352 | ubd_dev->no_cow = 1; |
1da177e4 | 353 | break; |
6c29256c | 354 | case 'c': |
7d314e34 | 355 | ubd_dev->shared = 1; |
6c29256c | 356 | break; |
1da177e4 LT |
357 | case '=': |
358 | str++; | |
359 | goto break_loop; | |
360 | default: | |
f28169d2 JD |
361 | *error_out = "Expected '=' or flag letter " |
362 | "(r, s, c, or d)"; | |
1da177e4 LT |
363 | goto out; |
364 | } | |
365 | str++; | |
366 | } | |
367 | ||
f28169d2 JD |
368 | if (*str == '=') |
369 | *error_out = "Too many flags specified"; | |
370 | else | |
371 | *error_out = "Missing '='"; | |
1da177e4 LT |
372 | goto out; |
373 | ||
374 | break_loop: | |
1da177e4 LT |
375 | backing_file = strchr(str, ','); |
376 | ||
f28169d2 | 377 | if (backing_file == NULL) |
1da177e4 | 378 | backing_file = strchr(str, ':'); |
1da177e4 | 379 | |
f28169d2 JD |
380 | if(backing_file != NULL){ |
381 | if(ubd_dev->no_cow){ | |
382 | *error_out = "Can't specify both 'd' and a cow file"; | |
383 | goto out; | |
384 | } | |
1da177e4 LT |
385 | else { |
386 | *backing_file = '\0'; | |
387 | backing_file++; | |
388 | } | |
389 | } | |
f28169d2 | 390 | err = 0; |
7d314e34 PBG |
391 | ubd_dev->file = str; |
392 | ubd_dev->cow.file = backing_file; | |
393 | ubd_dev->boot_openflags = flags; | |
1da177e4 | 394 | out: |
d7fb2c38 | 395 | mutex_unlock(&ubd_lock); |
f28169d2 | 396 | return err; |
1da177e4 LT |
397 | } |
398 | ||
399 | static int ubd_setup(char *str) | |
400 | { | |
f28169d2 JD |
401 | char *error; |
402 | int err; | |
403 | ||
404 | err = ubd_setup_common(str, NULL, &error); | |
405 | if(err) | |
406 | printk(KERN_ERR "Failed to initialize device with \"%s\" : " | |
407 | "%s\n", str, error); | |
408 | return 1; | |
1da177e4 LT |
409 | } |
410 | ||
411 | __setup("ubd", ubd_setup); | |
412 | __uml_help(ubd_setup, | |
413 | "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" | |
414 | " This is used to associate a device with a file in the underlying\n" | |
415 | " filesystem. When specifying two filenames, the first one is the\n" | |
416 | " COW name and the second is the backing file name. As separator you can\n" | |
417 | " use either a ':' or a ',': the first one allows writing things like;\n" | |
418 | " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" | |
419 | " while with a ',' the shell would not expand the 2nd '~'.\n" | |
f28169d2 | 420 | " When using only one filename, UML will detect whether to treat it like\n" |
1da177e4 LT |
421 | " a COW file or a backing file. To override this detection, add the 'd'\n" |
422 | " flag:\n" | |
423 | " ubd0d=BackingFile\n" | |
424 | " Usually, there is a filesystem in the file, but \n" | |
425 | " that's not required. Swap devices containing swap files can be\n" | |
426 | " specified like this. Also, a file which doesn't contain a\n" | |
427 | " filesystem can have its contents read in the virtual \n" | |
428 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
429 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
430 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
20ede453 JD |
431 | " an 's' will cause data to be written to disk on the host immediately.\n" |
432 | " 'c' will cause the device to be treated as being shared between multiple\n" | |
433 | " UMLs and file locking will be turned off - this is appropriate for a\n" | |
434 | " cluster filesystem and inappropriate at almost all other times.\n\n" | |
1da177e4 LT |
435 | ); |
436 | ||
8299ca5c | 437 | static int udb_setup(char *str) |
1da177e4 LT |
438 | { |
439 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
440 | "udb TYPO\n", str); | |
dc764e50 | 441 | return 1; |
1da177e4 LT |
442 | } |
443 | ||
444 | __setup("udb", udb_setup); | |
445 | __uml_help(udb_setup, | |
446 | "udb\n" | |
0894e27e JD |
447 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
448 | " to impossible to catch visually unless you specifically look for\n" | |
449 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
450 | " in the boot output.\n\n" |
451 | ); | |
452 | ||
165125e1 | 453 | static void do_ubd_request(struct request_queue * q); |
91acb21f JD |
454 | |
455 | /* Only changed by ubd_init, which is an initcall. */ | |
5dc62b1b | 456 | static int thread_fd = -1; |
a0044bdf JD |
457 | static LIST_HEAD(restart); |
458 | ||
2fe30a34 | 459 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 460 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 461 | static void ubd_handler(void) |
1da177e4 | 462 | { |
2adcec21 | 463 | struct io_thread_req *req; |
a0044bdf JD |
464 | struct ubd *ubd; |
465 | struct list_head *list, *next_ele; | |
466 | unsigned long flags; | |
91acb21f JD |
467 | int n; |
468 | ||
a0044bdf | 469 | while(1){ |
a6ea4cce JD |
470 | n = os_read_file(thread_fd, &req, |
471 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
472 | if(n != sizeof(req)){ |
473 | if(n == -EAGAIN) | |
474 | break; | |
475 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
476 | "err = %d\n", -n); | |
477 | return; | |
478 | } | |
62f96cb0 | 479 | |
4d6c84d9 | 480 | blk_end_request(req->req, 0, req->length); |
2adcec21 | 481 | kfree(req); |
a0044bdf | 482 | } |
62f96cb0 | 483 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
484 | |
485 | list_for_each_safe(list, next_ele, &restart){ | |
486 | ubd = container_of(list, struct ubd, restart); | |
487 | list_del_init(&ubd->restart); | |
488 | spin_lock_irqsave(&ubd->lock, flags); | |
489 | do_ubd_request(ubd->queue); | |
490 | spin_unlock_irqrestore(&ubd->lock, flags); | |
491 | } | |
1da177e4 LT |
492 | } |
493 | ||
7bea96fd | 494 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 495 | { |
91acb21f | 496 | ubd_handler(); |
dc764e50 | 497 | return IRQ_HANDLED; |
91acb21f | 498 | } |
09ace81c | 499 | |
91acb21f JD |
500 | /* Only changed by ubd_init, which is an initcall. */ |
501 | static int io_pid = -1; | |
09ace81c | 502 | |
5dc62b1b | 503 | static void kill_io_thread(void) |
91acb21f | 504 | { |
6c29256c | 505 | if(io_pid != -1) |
91acb21f | 506 | os_kill_process(io_pid, 1); |
09ace81c | 507 | } |
1da177e4 | 508 | |
91acb21f JD |
509 | __uml_exitcall(kill_io_thread); |
510 | ||
d8d7c28e | 511 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
512 | { |
513 | char *file; | |
85356398 RW |
514 | int fd; |
515 | int err; | |
516 | ||
517 | __u32 version; | |
518 | __u32 align; | |
519 | char *backing_file; | |
520 | time_t mtime; | |
521 | unsigned long long size; | |
522 | int sector_size; | |
523 | int bitmap_offset; | |
524 | ||
525 | if (ubd_dev->file && ubd_dev->cow.file) { | |
526 | file = ubd_dev->cow.file; | |
527 | ||
528 | goto out; | |
529 | } | |
530 | ||
531 | fd = os_open_file(ubd_dev->file, global_openflags, 0); | |
532 | if (fd < 0) | |
533 | return fd; | |
534 | ||
535 | err = read_cow_header(file_reader, &fd, &version, &backing_file, \ | |
536 | &mtime, &size, §or_size, &align, &bitmap_offset); | |
537 | os_close_file(fd); | |
1da177e4 | 538 | |
85356398 RW |
539 | if(err == -EINVAL) |
540 | file = ubd_dev->file; | |
541 | else | |
542 | file = backing_file; | |
543 | ||
544 | out: | |
dc764e50 | 545 | return os_file_size(file, size_out); |
1da177e4 LT |
546 | } |
547 | ||
5dc62b1b WC |
548 | static int read_cow_bitmap(int fd, void *buf, int offset, int len) |
549 | { | |
550 | int err; | |
551 | ||
552 | err = os_seek_file(fd, offset); | |
553 | if (err < 0) | |
554 | return err; | |
555 | ||
556 | err = os_read_file(fd, buf, len); | |
557 | if (err < 0) | |
558 | return err; | |
559 | ||
560 | return 0; | |
561 | } | |
562 | ||
563 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
564 | { | |
565 | unsigned long modtime; | |
566 | unsigned long long actual; | |
567 | int err; | |
568 | ||
569 | err = os_file_modtime(file, &modtime); | |
570 | if (err < 0) { | |
571 | printk(KERN_ERR "Failed to get modification time of backing " | |
572 | "file \"%s\", err = %d\n", file, -err); | |
573 | return err; | |
574 | } | |
575 | ||
576 | err = os_file_size(file, &actual); | |
577 | if (err < 0) { | |
578 | printk(KERN_ERR "Failed to get size of backing file \"%s\", " | |
579 | "err = %d\n", file, -err); | |
580 | return err; | |
581 | } | |
582 | ||
583 | if (actual != size) { | |
584 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
585 | * the typecast.*/ | |
586 | printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " | |
587 | "vs backing file\n", (unsigned long long) size, actual); | |
588 | return -EINVAL; | |
589 | } | |
590 | if (modtime != mtime) { | |
591 | printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " | |
592 | "backing file\n", mtime, modtime); | |
593 | return -EINVAL; | |
594 | } | |
595 | return 0; | |
596 | } | |
597 | ||
598 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) | |
599 | { | |
600 | struct uml_stat buf1, buf2; | |
601 | int err; | |
602 | ||
603 | if (from_cmdline == NULL) | |
604 | return 0; | |
605 | if (!strcmp(from_cmdline, from_cow)) | |
606 | return 0; | |
607 | ||
608 | err = os_stat_file(from_cmdline, &buf1); | |
609 | if (err < 0) { | |
610 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, | |
611 | -err); | |
612 | return 0; | |
613 | } | |
614 | err = os_stat_file(from_cow, &buf2); | |
615 | if (err < 0) { | |
616 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, | |
617 | -err); | |
618 | return 1; | |
619 | } | |
620 | if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
621 | return 0; | |
622 | ||
623 | printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " | |
624 | "\"%s\" specified in COW header of \"%s\"\n", | |
625 | from_cmdline, from_cow, cow); | |
626 | return 1; | |
627 | } | |
628 | ||
629 | static int open_ubd_file(char *file, struct openflags *openflags, int shared, | |
630 | char **backing_file_out, int *bitmap_offset_out, | |
631 | unsigned long *bitmap_len_out, int *data_offset_out, | |
632 | int *create_cow_out) | |
633 | { | |
634 | time_t mtime; | |
635 | unsigned long long size; | |
636 | __u32 version, align; | |
637 | char *backing_file; | |
638 | int fd, err, sectorsize, asked_switch, mode = 0644; | |
639 | ||
640 | fd = os_open_file(file, *openflags, mode); | |
641 | if (fd < 0) { | |
642 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
643 | *create_cow_out = 1; | |
644 | if (!openflags->w || | |
645 | ((fd != -EROFS) && (fd != -EACCES))) | |
646 | return fd; | |
647 | openflags->w = 0; | |
648 | fd = os_open_file(file, *openflags, mode); | |
649 | if (fd < 0) | |
650 | return fd; | |
651 | } | |
652 | ||
653 | if (shared) | |
654 | printk(KERN_INFO "Not locking \"%s\" on the host\n", file); | |
655 | else { | |
656 | err = os_lock_file(fd, openflags->w); | |
657 | if (err < 0) { | |
658 | printk(KERN_ERR "Failed to lock '%s', err = %d\n", | |
659 | file, -err); | |
660 | goto out_close; | |
661 | } | |
662 | } | |
663 | ||
664 | /* Successful return case! */ | |
665 | if (backing_file_out == NULL) | |
666 | return fd; | |
667 | ||
668 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
669 | &size, §orsize, &align, bitmap_offset_out); | |
670 | if (err && (*backing_file_out != NULL)) { | |
671 | printk(KERN_ERR "Failed to read COW header from COW file " | |
672 | "\"%s\", errno = %d\n", file, -err); | |
673 | goto out_close; | |
674 | } | |
675 | if (err) | |
676 | return fd; | |
677 | ||
678 | asked_switch = path_requires_switch(*backing_file_out, backing_file, | |
679 | file); | |
680 | ||
681 | /* Allow switching only if no mismatch. */ | |
682 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, | |
683 | mtime)) { | |
684 | printk(KERN_ERR "Switching backing file to '%s'\n", | |
685 | *backing_file_out); | |
686 | err = write_cow_header(file, fd, *backing_file_out, | |
687 | sectorsize, align, &size); | |
688 | if (err) { | |
689 | printk(KERN_ERR "Switch failed, errno = %d\n", -err); | |
690 | goto out_close; | |
691 | } | |
692 | } else { | |
693 | *backing_file_out = backing_file; | |
694 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
695 | if (err) | |
696 | goto out_close; | |
697 | } | |
698 | ||
699 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
700 | bitmap_len_out, data_offset_out); | |
701 | ||
702 | return fd; | |
703 | out_close: | |
704 | os_close_file(fd); | |
705 | return err; | |
706 | } | |
707 | ||
708 | static int create_cow_file(char *cow_file, char *backing_file, | |
709 | struct openflags flags, | |
710 | int sectorsize, int alignment, int *bitmap_offset_out, | |
711 | unsigned long *bitmap_len_out, int *data_offset_out) | |
712 | { | |
713 | int err, fd; | |
714 | ||
715 | flags.c = 1; | |
716 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); | |
717 | if (fd < 0) { | |
718 | err = fd; | |
719 | printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", | |
720 | cow_file, -err); | |
721 | goto out; | |
722 | } | |
723 | ||
724 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
725 | bitmap_offset_out, bitmap_len_out, | |
726 | data_offset_out); | |
727 | if (!err) | |
728 | return fd; | |
729 | os_close_file(fd); | |
730 | out: | |
731 | return err; | |
732 | } | |
733 | ||
5f75a4f8 | 734 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 735 | { |
7d314e34 PBG |
736 | os_close_file(ubd_dev->fd); |
737 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
738 | return; |
739 | ||
7d314e34 PBG |
740 | os_close_file(ubd_dev->cow.fd); |
741 | vfree(ubd_dev->cow.bitmap); | |
742 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
743 | } |
744 | ||
7d314e34 | 745 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
746 | { |
747 | struct openflags flags; | |
748 | char **back_ptr; | |
749 | int err, create_cow, *create_ptr; | |
0bf16bff | 750 | int fd; |
1da177e4 | 751 | |
7d314e34 | 752 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 753 | create_cow = 0; |
7d314e34 PBG |
754 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
755 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
756 | |
757 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
758 | back_ptr, &ubd_dev->cow.bitmap_offset, |
759 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 760 | create_ptr); |
1da177e4 | 761 | |
0bf16bff PBG |
762 | if((fd == -ENOENT) && create_cow){ |
763 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
764 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
765 | &ubd_dev->cow.bitmap_offset, | |
766 | &ubd_dev->cow.bitmap_len, | |
767 | &ubd_dev->cow.data_offset); | |
0bf16bff | 768 | if(fd >= 0){ |
1da177e4 | 769 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 770 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
771 | } |
772 | } | |
773 | ||
0bf16bff | 774 | if(fd < 0){ |
7d314e34 | 775 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
776 | -fd); |
777 | return fd; | |
1da177e4 | 778 | } |
0bf16bff | 779 | ubd_dev->fd = fd; |
1da177e4 | 780 | |
7d314e34 | 781 | if(ubd_dev->cow.file != NULL){ |
086fa5ff | 782 | blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); |
f4768ffd | 783 | |
1da177e4 | 784 | err = -ENOMEM; |
da2486ba | 785 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 786 | if(ubd_dev->cow.bitmap == NULL){ |
1da177e4 LT |
787 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
788 | goto error; | |
789 | } | |
790 | flush_tlb_kernel_vm(); | |
791 | ||
7d314e34 PBG |
792 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
793 | ubd_dev->cow.bitmap_offset, | |
794 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
795 | if(err < 0) |
796 | goto error; | |
797 | ||
7d314e34 | 798 | flags = ubd_dev->openflags; |
1da177e4 | 799 | flags.w = 0; |
7d314e34 | 800 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 801 | NULL, NULL, NULL, NULL); |
1da177e4 | 802 | if(err < 0) goto error; |
7d314e34 | 803 | ubd_dev->cow.fd = err; |
1da177e4 | 804 | } |
dc764e50 | 805 | return 0; |
1da177e4 | 806 | error: |
7d314e34 | 807 | os_close_file(ubd_dev->fd); |
dc764e50 | 808 | return err; |
1da177e4 LT |
809 | } |
810 | ||
2e3f5251 JD |
811 | static void ubd_device_release(struct device *dev) |
812 | { | |
8691b97b | 813 | struct ubd *ubd_dev = dev_get_drvdata(dev); |
2e3f5251 JD |
814 | |
815 | blk_cleanup_queue(ubd_dev->queue); | |
816 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
817 | } | |
818 | ||
5f75a4f8 | 819 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 820 | struct gendisk **disk_out) |
1da177e4 LT |
821 | { |
822 | struct gendisk *disk; | |
1da177e4 LT |
823 | |
824 | disk = alloc_disk(1 << UBD_SHIFT); | |
825 | if(disk == NULL) | |
dc764e50 | 826 | return -ENOMEM; |
1da177e4 LT |
827 | |
828 | disk->major = major; | |
829 | disk->first_minor = unit << UBD_SHIFT; | |
830 | disk->fops = &ubd_blops; | |
831 | set_capacity(disk, size / 512); | |
792dd4fc | 832 | if (major == UBD_MAJOR) |
1da177e4 | 833 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 834 | else |
1da177e4 | 835 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
836 | |
837 | /* sysfs register (not for ide fake devices) */ | |
792dd4fc | 838 | if (major == UBD_MAJOR) { |
7d314e34 PBG |
839 | ubd_devs[unit].pdev.id = unit; |
840 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 | 841 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
8691b97b | 842 | dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); |
7d314e34 PBG |
843 | platform_device_register(&ubd_devs[unit].pdev); |
844 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
845 | } |
846 | ||
7d314e34 | 847 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 848 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
849 | add_disk(disk); |
850 | ||
851 | *disk_out = disk; | |
852 | return 0; | |
853 | } | |
854 | ||
855 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
856 | ||
f28169d2 | 857 | static int ubd_add(int n, char **error_out) |
1da177e4 | 858 | { |
7d314e34 | 859 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 860 | int err = 0; |
1da177e4 | 861 | |
7d314e34 | 862 | if(ubd_dev->file == NULL) |
ec7cf783 | 863 | goto out; |
1da177e4 | 864 | |
7d314e34 | 865 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
866 | if(err < 0){ |
867 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 868 | goto out; |
f28169d2 | 869 | } |
1da177e4 | 870 | |
7d314e34 | 871 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 872 | |
a0044bdf | 873 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 874 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 875 | |
62f96cb0 JD |
876 | err = -ENOMEM; |
877 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
878 | if (ubd_dev->queue == NULL) { | |
879 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 880 | goto out; |
62f96cb0 JD |
881 | } |
882 | ubd_dev->queue->queuedata = ubd_dev; | |
883 | ||
8a78362c | 884 | blk_queue_max_segments(ubd_dev->queue, MAX_SG); |
792dd4fc | 885 | err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); |
62f96cb0 JD |
886 | if(err){ |
887 | *error_out = "Failed to register device"; | |
888 | goto out_cleanup; | |
889 | } | |
6c29256c | 890 | |
792dd4fc | 891 | if (fake_major != UBD_MAJOR) |
5f75a4f8 | 892 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 893 | &fake_gendisk[n]); |
1da177e4 | 894 | |
83380cc1 JD |
895 | /* |
896 | * Perhaps this should also be under the "if (fake_major)" above | |
897 | * using the fake_disk->disk_name | |
898 | */ | |
1da177e4 LT |
899 | if (fake_ide) |
900 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
901 | ||
ec7cf783 | 902 | err = 0; |
ec7cf783 JD |
903 | out: |
904 | return err; | |
62f96cb0 JD |
905 | |
906 | out_cleanup: | |
907 | blk_cleanup_queue(ubd_dev->queue); | |
908 | goto out; | |
1da177e4 LT |
909 | } |
910 | ||
f28169d2 | 911 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 912 | { |
e7f6552f | 913 | int n, ret; |
1da177e4 | 914 | |
f28169d2 JD |
915 | /* This string is possibly broken up and stored, so it's only |
916 | * freed if ubd_setup_common fails, or if only general options | |
917 | * were set. | |
918 | */ | |
970d6e3a | 919 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 920 | if (str == NULL) { |
f28169d2 JD |
921 | *error_out = "Failed to allocate memory"; |
922 | return -ENOMEM; | |
1da177e4 | 923 | } |
f28169d2 JD |
924 | |
925 | ret = ubd_setup_common(str, &n, error_out); | |
926 | if (ret) | |
e7f6552f | 927 | goto err_free; |
f28169d2 | 928 | |
e7f6552f PBG |
929 | if (n == -1) { |
930 | ret = 0; | |
d8d7c28e | 931 | goto err_free; |
1da177e4 | 932 | } |
1da177e4 | 933 | |
dc764e50 | 934 | mutex_lock(&ubd_lock); |
f28169d2 | 935 | ret = ubd_add(n, error_out); |
e7f6552f | 936 | if (ret) |
7d314e34 | 937 | ubd_devs[n].file = NULL; |
dc764e50 | 938 | mutex_unlock(&ubd_lock); |
1da177e4 | 939 | |
e7f6552f | 940 | out: |
dc764e50 | 941 | return ret; |
e7f6552f PBG |
942 | |
943 | err_free: | |
944 | kfree(str); | |
945 | goto out; | |
1da177e4 LT |
946 | } |
947 | ||
948 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
949 | { | |
7d314e34 | 950 | struct ubd *ubd_dev; |
1da177e4 LT |
951 | int n, len = 0; |
952 | ||
953 | n = parse_unit(&name); | |
954 | if((n >= MAX_DEV) || (n < 0)){ | |
955 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 956 | return -1; |
1da177e4 LT |
957 | } |
958 | ||
7d314e34 | 959 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 960 | mutex_lock(&ubd_lock); |
1da177e4 | 961 | |
7d314e34 | 962 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
963 | CONFIG_CHUNK(str, size, len, "", 1); |
964 | goto out; | |
965 | } | |
966 | ||
7d314e34 | 967 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 968 | |
7d314e34 | 969 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 970 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 971 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
972 | } |
973 | else CONFIG_CHUNK(str, size, len, "", 1); | |
974 | ||
975 | out: | |
d7fb2c38 | 976 | mutex_unlock(&ubd_lock); |
dc764e50 | 977 | return len; |
1da177e4 LT |
978 | } |
979 | ||
29d56cfe JD |
980 | static int ubd_id(char **str, int *start_out, int *end_out) |
981 | { | |
dc764e50 | 982 | int n; |
29d56cfe JD |
983 | |
984 | n = parse_unit(str); | |
dc764e50 JD |
985 | *start_out = 0; |
986 | *end_out = MAX_DEV - 1; | |
987 | return n; | |
29d56cfe JD |
988 | } |
989 | ||
f28169d2 | 990 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 991 | { |
2e3f5251 | 992 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 993 | struct ubd *ubd_dev; |
29d56cfe | 994 | int err = -ENODEV; |
1da177e4 | 995 | |
d7fb2c38 | 996 | mutex_lock(&ubd_lock); |
1da177e4 | 997 | |
7d314e34 | 998 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 999 | |
7d314e34 | 1000 | if(ubd_dev->file == NULL) |
29d56cfe | 1001 | goto out; |
1da177e4 | 1002 | |
29d56cfe JD |
1003 | /* you cannot remove a open disk */ |
1004 | err = -EBUSY; | |
7d314e34 | 1005 | if(ubd_dev->count > 0) |
1da177e4 LT |
1006 | goto out; |
1007 | ||
dc764e50 | 1008 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
1009 | if(disk != NULL){ |
1010 | del_gendisk(disk); | |
1011 | put_disk(disk); | |
1012 | } | |
1da177e4 LT |
1013 | |
1014 | if(fake_gendisk[n] != NULL){ | |
1015 | del_gendisk(fake_gendisk[n]); | |
1016 | put_disk(fake_gendisk[n]); | |
1017 | fake_gendisk[n] = NULL; | |
1018 | } | |
1019 | ||
1da177e4 | 1020 | err = 0; |
2e3f5251 | 1021 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 1022 | out: |
d7fb2c38 | 1023 | mutex_unlock(&ubd_lock); |
29d56cfe | 1024 | return err; |
1da177e4 LT |
1025 | } |
1026 | ||
f28169d2 | 1027 | /* All these are called by mconsole in process context and without |
b8831a1d | 1028 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 1029 | */ |
1da177e4 | 1030 | static struct mc_device ubd_mc = { |
84f48d4f | 1031 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
1032 | .name = "ubd", |
1033 | .config = ubd_config, | |
dc764e50 | 1034 | .get_config = ubd_get_config, |
29d56cfe | 1035 | .id = ubd_id, |
1da177e4 LT |
1036 | .remove = ubd_remove, |
1037 | }; | |
1038 | ||
d8d7c28e | 1039 | static int __init ubd_mc_init(void) |
1da177e4 LT |
1040 | { |
1041 | mconsole_register_dev(&ubd_mc); | |
1042 | return 0; | |
1043 | } | |
1044 | ||
1045 | __initcall(ubd_mc_init); | |
1046 | ||
d8d7c28e PBG |
1047 | static int __init ubd0_init(void) |
1048 | { | |
1049 | struct ubd *ubd_dev = &ubd_devs[0]; | |
1050 | ||
b8831a1d | 1051 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
1052 | if(ubd_dev->file == NULL) |
1053 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
1054 | mutex_unlock(&ubd_lock); |
1055 | ||
dc764e50 | 1056 | return 0; |
d8d7c28e PBG |
1057 | } |
1058 | ||
1059 | __initcall(ubd0_init); | |
1060 | ||
b8831a1d | 1061 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
1062 | static struct platform_driver ubd_driver = { |
1063 | .driver = { | |
1064 | .name = DRIVER_NAME, | |
1065 | }, | |
1da177e4 LT |
1066 | }; |
1067 | ||
d8d7c28e | 1068 | static int __init ubd_init(void) |
1da177e4 | 1069 | { |
f28169d2 JD |
1070 | char *error; |
1071 | int i, err; | |
1da177e4 | 1072 | |
792dd4fc | 1073 | if (register_blkdev(UBD_MAJOR, "ubd")) |
1da177e4 LT |
1074 | return -1; |
1075 | ||
792dd4fc | 1076 | if (fake_major != UBD_MAJOR) { |
1da177e4 LT |
1077 | char name[sizeof("ubd_nnn\0")]; |
1078 | ||
1079 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
1080 | if (register_blkdev(fake_major, "ubd")) |
1081 | return -1; | |
1082 | } | |
3ae5eaec | 1083 | platform_driver_register(&ubd_driver); |
dc764e50 | 1084 | mutex_lock(&ubd_lock); |
f28169d2 JD |
1085 | for (i = 0; i < MAX_DEV; i++){ |
1086 | err = ubd_add(i, &error); | |
1087 | if(err) | |
1088 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
1089 | "%s\n", i, error); | |
1090 | } | |
dc764e50 | 1091 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
1092 | return 0; |
1093 | } | |
1094 | ||
1095 | late_initcall(ubd_init); | |
1096 | ||
d8d7c28e | 1097 | static int __init ubd_driver_init(void){ |
91acb21f JD |
1098 | unsigned long stack; |
1099 | int err; | |
1100 | ||
1101 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
1102 | if(global_openflags.s){ | |
1103 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
1104 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
1105 | * enough. So use anyway the io thread. */ | |
1106 | } | |
1107 | stack = alloc_stack(0, 0); | |
6c29256c | 1108 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
1109 | &thread_fd); |
1110 | if(io_pid < 0){ | |
6c29256c | 1111 | printk(KERN_ERR |
91acb21f JD |
1112 | "ubd : Failed to start I/O thread (errno = %d) - " |
1113 | "falling back to synchronous I/O\n", -io_pid); | |
1114 | io_pid = -1; | |
dc764e50 | 1115 | return 0; |
91acb21f | 1116 | } |
6c29256c | 1117 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
c0b79a90 | 1118 | 0, "ubd", ubd_devs); |
91acb21f JD |
1119 | if(err != 0) |
1120 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 1121 | return 0; |
91acb21f JD |
1122 | } |
1123 | ||
1124 | device_initcall(ubd_driver_init); | |
1125 | ||
a625c998 | 1126 | static int ubd_open(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1127 | { |
a625c998 | 1128 | struct gendisk *disk = bdev->bd_disk; |
7d314e34 | 1129 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
1130 | int err = 0; |
1131 | ||
9a181c58 | 1132 | mutex_lock(&ubd_mutex); |
7d314e34 PBG |
1133 | if(ubd_dev->count == 0){ |
1134 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
1135 | if(err){ |
1136 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 1137 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
1138 | goto out; |
1139 | } | |
1140 | } | |
7d314e34 PBG |
1141 | ubd_dev->count++; |
1142 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
1143 | |
1144 | /* This should no more be needed. And it didn't work anyway to exclude | |
1145 | * read-write remounting of filesystems.*/ | |
a625c998 | 1146 | /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 1147 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 1148 | err = -EROFS; |
2c49be99 | 1149 | }*/ |
6e9624b8 | 1150 | out: |
9a181c58 | 1151 | mutex_unlock(&ubd_mutex); |
dc764e50 | 1152 | return err; |
1da177e4 LT |
1153 | } |
1154 | ||
a625c998 | 1155 | static int ubd_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 1156 | { |
7d314e34 | 1157 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 1158 | |
9a181c58 | 1159 | mutex_lock(&ubd_mutex); |
7d314e34 | 1160 | if(--ubd_dev->count == 0) |
5f75a4f8 | 1161 | ubd_close_dev(ubd_dev); |
9a181c58 | 1162 | mutex_unlock(&ubd_mutex); |
dc764e50 | 1163 | return 0; |
1da177e4 LT |
1164 | } |
1165 | ||
91acb21f JD |
1166 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
1167 | __u64 *cow_offset, unsigned long *bitmap, | |
1168 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
1169 | __u64 bitmap_len) | |
1da177e4 | 1170 | { |
91acb21f JD |
1171 | __u64 sector = io_offset >> 9; |
1172 | int i, update_bitmap = 0; | |
1173 | ||
1174 | for(i = 0; i < length >> 9; i++){ | |
1175 | if(cow_mask != NULL) | |
1176 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1177 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1178 | continue; | |
1da177e4 | 1179 | |
91acb21f JD |
1180 | update_bitmap = 1; |
1181 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1182 | } | |
1183 | ||
1184 | if(!update_bitmap) | |
1185 | return; | |
1da177e4 | 1186 | |
91acb21f | 1187 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1188 | |
91acb21f JD |
1189 | /* This takes care of the case where we're exactly at the end of the |
1190 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1191 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1192 | * for the original diagnosis. | |
1193 | */ | |
6d074242 JO |
1194 | if (*cow_offset == (DIV_ROUND_UP(bitmap_len, |
1195 | sizeof(unsigned long)) - 1)) | |
91acb21f JD |
1196 | (*cow_offset)--; |
1197 | ||
1198 | bitmap_words[0] = bitmap[*cow_offset]; | |
1199 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1200 | ||
1201 | *cow_offset *= sizeof(unsigned long); | |
1202 | *cow_offset += bitmap_offset; | |
1203 | } | |
1204 | ||
1205 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1206 | __u64 bitmap_offset, __u64 bitmap_len) | |
1207 | { | |
1208 | __u64 sector = req->offset >> 9; | |
1209 | int i; | |
1210 | ||
1211 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1212 | panic("Operation too long"); | |
1213 | ||
1214 | if(req->op == UBD_READ) { | |
1215 | for(i = 0; i < req->length >> 9; i++){ | |
1216 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1217 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1218 | &req->sector_mask); |
dc764e50 | 1219 | } |
91acb21f JD |
1220 | } |
1221 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1222 | &req->cow_offset, bitmap, bitmap_offset, | |
1223 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1224 | } |
1225 | ||
62f96cb0 | 1226 | /* Called with dev->lock held */ |
a0044bdf JD |
1227 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1228 | unsigned long long offset, int page_offset, | |
1229 | int len, struct page *page) | |
1da177e4 LT |
1230 | { |
1231 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1232 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1233 | |
62f96cb0 | 1234 | io_req->req = req; |
a0044bdf JD |
1235 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1236 | ubd_dev->fd; | |
7d314e34 | 1237 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1238 | io_req->cow_offset = -1; |
1da177e4 LT |
1239 | io_req->offset = offset; |
1240 | io_req->length = len; | |
1241 | io_req->error = 0; | |
91acb21f JD |
1242 | io_req->sector_mask = 0; |
1243 | ||
1244 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1245 | io_req->offsets[0] = 0; |
7d314e34 | 1246 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1247 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1248 | io_req->sectorsize = 1 << 9; |
1249 | ||
7d314e34 | 1250 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1251 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1252 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1253 | |
1da177e4 LT |
1254 | } |
1255 | ||
62f96cb0 | 1256 | /* Called with dev->lock held */ |
165125e1 | 1257 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1258 | { |
2adcec21 | 1259 | struct io_thread_req *io_req; |
1da177e4 | 1260 | struct request *req; |
f81f2f7c | 1261 | int n; |
a0044bdf JD |
1262 | |
1263 | while(1){ | |
2a9529a0 | 1264 | struct ubd *dev = q->queuedata; |
a0044bdf | 1265 | if(dev->end_sg == 0){ |
9934c8c0 | 1266 | struct request *req = blk_fetch_request(q); |
a0044bdf JD |
1267 | if(req == NULL) |
1268 | return; | |
1269 | ||
1270 | dev->request = req; | |
47526903 | 1271 | dev->rq_pos = blk_rq_pos(req); |
a0044bdf JD |
1272 | dev->start_sg = 0; |
1273 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1274 | } | |
1275 | ||
1276 | req = dev->request; | |
1277 | while(dev->start_sg < dev->end_sg){ | |
1278 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1279 | ||
2adcec21 | 1280 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1281 | GFP_ATOMIC); |
2adcec21 JD |
1282 | if(io_req == NULL){ |
1283 | if(list_empty(&dev->restart)) | |
1284 | list_add(&dev->restart, &restart); | |
1285 | return; | |
1286 | } | |
1287 | prepare_request(req, io_req, | |
47526903 | 1288 | (unsigned long long)dev->rq_pos << 9, |
45711f1a | 1289 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1290 | |
a6ea4cce JD |
1291 | n = os_write_file(thread_fd, &io_req, |
1292 | sizeof(struct io_thread_req *)); | |
2adcec21 | 1293 | if(n != sizeof(struct io_thread_req *)){ |
a0044bdf JD |
1294 | if(n != -EAGAIN) |
1295 | printk("write to io thread failed, " | |
1296 | "errno = %d\n", -n); | |
1297 | else if(list_empty(&dev->restart)) | |
1298 | list_add(&dev->restart, &restart); | |
12429bf9 | 1299 | kfree(io_req); |
a0044bdf JD |
1300 | return; |
1301 | } | |
1302 | ||
47526903 | 1303 | dev->rq_pos += sg->length >> 9; |
a0044bdf | 1304 | dev->start_sg++; |
1da177e4 | 1305 | } |
a0044bdf JD |
1306 | dev->end_sg = 0; |
1307 | dev->request = NULL; | |
1da177e4 LT |
1308 | } |
1309 | } | |
1310 | ||
a885c8c4 CH |
1311 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1312 | { | |
7d314e34 | 1313 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1314 | |
1315 | geo->heads = 128; | |
1316 | geo->sectors = 32; | |
7d314e34 | 1317 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1318 | return 0; |
1319 | } | |
1320 | ||
a625c998 | 1321 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 LT |
1322 | unsigned int cmd, unsigned long arg) |
1323 | { | |
a625c998 | 1324 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
73855e13 | 1325 | u16 ubd_id[ATA_ID_WORDS]; |
1da177e4 LT |
1326 | |
1327 | switch (cmd) { | |
1da177e4 | 1328 | struct cdrom_volctrl volume; |
1da177e4 | 1329 | case HDIO_GET_IDENTITY: |
73855e13 BZ |
1330 | memset(&ubd_id, 0, ATA_ID_WORDS * 2); |
1331 | ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); | |
1332 | ubd_id[ATA_ID_HEADS] = 128; | |
1333 | ubd_id[ATA_ID_SECTORS] = 32; | |
1da177e4 LT |
1334 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1335 | sizeof(ubd_id))) | |
dc764e50 JD |
1336 | return -EFAULT; |
1337 | return 0; | |
b8831a1d | 1338 | |
1da177e4 LT |
1339 | case CDROMVOLREAD: |
1340 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1341 | return -EFAULT; |
1da177e4 LT |
1342 | volume.channel0 = 255; |
1343 | volume.channel1 = 255; | |
1344 | volume.channel2 = 255; | |
1345 | volume.channel3 = 255; | |
1346 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1347 | return -EFAULT; |
1348 | return 0; | |
1da177e4 | 1349 | } |
dc764e50 | 1350 | return -EINVAL; |
1da177e4 LT |
1351 | } |
1352 | ||
91acb21f | 1353 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1354 | { |
91acb21f | 1355 | int n; |
1da177e4 | 1356 | |
91acb21f | 1357 | if(req->cow_offset == -1) |
dc764e50 | 1358 | return 0; |
1da177e4 | 1359 | |
91acb21f JD |
1360 | n = os_seek_file(req->fds[1], req->cow_offset); |
1361 | if(n < 0){ | |
1362 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
dc764e50 | 1363 | return 1; |
91acb21f | 1364 | } |
1da177e4 | 1365 | |
a6ea4cce JD |
1366 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1367 | sizeof(req->bitmap_words)); | |
91acb21f JD |
1368 | if(n != sizeof(req->bitmap_words)){ |
1369 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1370 | req->fds[1]); | |
dc764e50 | 1371 | return 1; |
91acb21f | 1372 | } |
1da177e4 | 1373 | |
dc764e50 | 1374 | return 0; |
91acb21f | 1375 | } |
1da177e4 | 1376 | |
5dc62b1b | 1377 | static void do_io(struct io_thread_req *req) |
91acb21f JD |
1378 | { |
1379 | char *buf; | |
1380 | unsigned long len; | |
1381 | int n, nsectors, start, end, bit; | |
1382 | int err; | |
1383 | __u64 off; | |
1384 | ||
1385 | nsectors = req->length / req->sectorsize; | |
1386 | start = 0; | |
1387 | do { | |
1388 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1389 | end = start; | |
1390 | while((end < nsectors) && | |
1391 | (ubd_test_bit(end, (unsigned char *) | |
1392 | &req->sector_mask) == bit)) | |
1393 | end++; | |
1394 | ||
1395 | off = req->offset + req->offsets[bit] + | |
1396 | start * req->sectorsize; | |
1397 | len = (end - start) * req->sectorsize; | |
1398 | buf = &req->buffer[start * req->sectorsize]; | |
1399 | ||
1400 | err = os_seek_file(req->fds[bit], off); | |
1401 | if(err < 0){ | |
1402 | printk("do_io - lseek failed : err = %d\n", -err); | |
1403 | req->error = 1; | |
1404 | return; | |
1405 | } | |
1406 | if(req->op == UBD_READ){ | |
1407 | n = 0; | |
1408 | do { | |
1409 | buf = &buf[n]; | |
1410 | len -= n; | |
a6ea4cce | 1411 | n = os_read_file(req->fds[bit], buf, len); |
91acb21f JD |
1412 | if (n < 0) { |
1413 | printk("do_io - read failed, err = %d " | |
1414 | "fd = %d\n", -n, req->fds[bit]); | |
1415 | req->error = 1; | |
1416 | return; | |
1417 | } | |
1418 | } while((n < len) && (n != 0)); | |
1419 | if (n < len) memset(&buf[n], 0, len - n); | |
1420 | } else { | |
a6ea4cce | 1421 | n = os_write_file(req->fds[bit], buf, len); |
91acb21f JD |
1422 | if(n != len){ |
1423 | printk("do_io - write failed err = %d " | |
1424 | "fd = %d\n", -n, req->fds[bit]); | |
1425 | req->error = 1; | |
1426 | return; | |
1427 | } | |
1428 | } | |
1429 | ||
1430 | start = end; | |
1431 | } while(start < nsectors); | |
1da177e4 | 1432 | |
91acb21f | 1433 | req->error = update_bitmap(req); |
1da177e4 | 1434 | } |
91acb21f JD |
1435 | |
1436 | /* Changed in start_io_thread, which is serialized by being called only | |
1437 | * from ubd_init, which is an initcall. | |
1438 | */ | |
1439 | int kernel_fd = -1; | |
1440 | ||
d8d7c28e PBG |
1441 | /* Only changed by the io thread. XXX: currently unused. */ |
1442 | static int io_count = 0; | |
91acb21f JD |
1443 | |
1444 | int io_thread(void *arg) | |
1445 | { | |
2adcec21 | 1446 | struct io_thread_req *req; |
91acb21f JD |
1447 | int n; |
1448 | ||
1449 | ignore_sigwinch_sig(); | |
1450 | while(1){ | |
a6ea4cce | 1451 | n = os_read_file(kernel_fd, &req, |
2adcec21 JD |
1452 | sizeof(struct io_thread_req *)); |
1453 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1454 | if(n < 0) |
1455 | printk("io_thread - read failed, fd = %d, " | |
1456 | "err = %d\n", kernel_fd, -n); | |
1457 | else { | |
1458 | printk("io_thread - short read, fd = %d, " | |
1459 | "length = %d\n", kernel_fd, n); | |
1460 | } | |
1461 | continue; | |
1462 | } | |
1463 | io_count++; | |
2adcec21 | 1464 | do_io(req); |
a6ea4cce | 1465 | n = os_write_file(kernel_fd, &req, |
2adcec21 JD |
1466 | sizeof(struct io_thread_req *)); |
1467 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1468 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1469 | kernel_fd, -n); | |
1470 | } | |
91acb21f | 1471 | |
1b57e9c2 JD |
1472 | return 0; |
1473 | } |