Commit | Line | Data |
---|---|---|
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 LT |
35 | #include "linux/vmalloc.h" |
36 | #include "linux/blkpg.h" | |
37 | #include "linux/genhd.h" | |
38 | #include "linux/spinlock.h" | |
d052d1be | 39 | #include "linux/platform_device.h" |
23464ffa | 40 | #include "linux/scatterlist.h" |
1da177e4 LT |
41 | #include "asm/segment.h" |
42 | #include "asm/uaccess.h" | |
43 | #include "asm/irq.h" | |
44 | #include "asm/types.h" | |
45 | #include "asm/tlbflush.h" | |
1da177e4 LT |
46 | #include "mem_user.h" |
47 | #include "kern_util.h" | |
48 | #include "kern.h" | |
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" | |
56 | #include "mem_kern.h" | |
57 | #include "cow.h" | |
58 | ||
7b9014c1 | 59 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
60 | |
61 | struct io_thread_req { | |
62f96cb0 | 62 | struct request *req; |
91acb21f | 63 | enum ubd_req op; |
1da177e4 LT |
64 | int fds[2]; |
65 | unsigned long offsets[2]; | |
66 | unsigned long long offset; | |
67 | unsigned long length; | |
68 | char *buffer; | |
69 | int sectorsize; | |
91acb21f JD |
70 | unsigned long sector_mask; |
71 | unsigned long long cow_offset; | |
72 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
73 | int error; |
74 | }; | |
75 | ||
91acb21f | 76 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
77 | { |
78 | __u64 n; | |
79 | int bits, off; | |
80 | ||
91acb21f | 81 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
82 | n = bit / bits; |
83 | off = bit % bits; | |
dc764e50 | 84 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
85 | } |
86 | ||
91acb21f | 87 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
88 | { |
89 | __u64 n; | |
90 | int bits, off; | |
91 | ||
91acb21f | 92 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
93 | n = bit / bits; |
94 | off = bit % bits; | |
91acb21f | 95 | data[n] |= (1 << off); |
1da177e4 LT |
96 | } |
97 | /*End stuff from ubd_user.h*/ | |
98 | ||
99 | #define DRIVER_NAME "uml-blkdev" | |
100 | ||
d7fb2c38 | 101 | static DEFINE_MUTEX(ubd_lock); |
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; | |
1da177e4 LT |
165 | }; |
166 | ||
167 | #define DEFAULT_COW { \ | |
168 | .file = NULL, \ | |
dc764e50 JD |
169 | .fd = -1, \ |
170 | .bitmap = NULL, \ | |
1da177e4 | 171 | .bitmap_offset = 0, \ |
dc764e50 | 172 | .data_offset = 0, \ |
1da177e4 LT |
173 | } |
174 | ||
175 | #define DEFAULT_UBD { \ | |
176 | .file = NULL, \ | |
177 | .count = 0, \ | |
178 | .fd = -1, \ | |
179 | .size = -1, \ | |
180 | .boot_openflags = OPEN_FLAGS, \ | |
181 | .openflags = OPEN_FLAGS, \ | |
dc764e50 | 182 | .no_cow = 0, \ |
6c29256c | 183 | .shared = 0, \ |
dc764e50 | 184 | .cow = DEFAULT_COW, \ |
62f96cb0 | 185 | .lock = SPIN_LOCK_UNLOCKED, \ |
a0044bdf JD |
186 | .request = NULL, \ |
187 | .start_sg = 0, \ | |
188 | .end_sg = 0, \ | |
1da177e4 LT |
189 | } |
190 | ||
b8831a1d | 191 | /* Protected by ubd_lock */ |
5dc62b1b | 192 | static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; |
1da177e4 | 193 | |
1da177e4 LT |
194 | /* Only changed by fake_ide_setup which is a setup */ |
195 | static int fake_ide = 0; | |
196 | static struct proc_dir_entry *proc_ide_root = NULL; | |
197 | static struct proc_dir_entry *proc_ide = NULL; | |
198 | ||
199 | static void make_proc_ide(void) | |
200 | { | |
201 | proc_ide_root = proc_mkdir("ide", NULL); | |
202 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
203 | } | |
204 | ||
6613c5e8 | 205 | static int fake_ide_media_proc_show(struct seq_file *m, void *v) |
1da177e4 | 206 | { |
6613c5e8 AD |
207 | seq_puts(m, "disk\n"); |
208 | return 0; | |
209 | } | |
210 | ||
211 | static int fake_ide_media_proc_open(struct inode *inode, struct file *file) | |
212 | { | |
213 | return single_open(file, fake_ide_media_proc_show, NULL); | |
1da177e4 LT |
214 | } |
215 | ||
6613c5e8 AD |
216 | static const struct file_operations fake_ide_media_proc_fops = { |
217 | .owner = THIS_MODULE, | |
218 | .open = fake_ide_media_proc_open, | |
219 | .read = seq_read, | |
220 | .llseek = seq_lseek, | |
221 | .release = single_release, | |
222 | }; | |
223 | ||
c0a9290e | 224 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
225 | { |
226 | struct proc_dir_entry *dir, *ent; | |
227 | char name[64]; | |
228 | ||
229 | if(proc_ide_root == NULL) make_proc_ide(); | |
230 | ||
231 | dir = proc_mkdir(dev_name, proc_ide); | |
232 | if(!dir) return; | |
233 | ||
6613c5e8 | 234 | ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); |
1da177e4 | 235 | if(!ent) return; |
c0a9290e | 236 | snprintf(name, sizeof(name), "ide0/%s", dev_name); |
1da177e4 LT |
237 | proc_symlink(dev_name, proc_ide_root, name); |
238 | } | |
239 | ||
240 | static int fake_ide_setup(char *str) | |
241 | { | |
242 | fake_ide = 1; | |
dc764e50 | 243 | return 1; |
1da177e4 LT |
244 | } |
245 | ||
246 | __setup("fake_ide", fake_ide_setup); | |
247 | ||
248 | __uml_help(fake_ide_setup, | |
249 | "fake_ide\n" | |
250 | " Create ide0 entries that map onto ubd devices.\n\n" | |
251 | ); | |
252 | ||
253 | static int parse_unit(char **ptr) | |
254 | { | |
255 | char *str = *ptr, *end; | |
256 | int n = -1; | |
257 | ||
258 | if(isdigit(*str)) { | |
259 | n = simple_strtoul(str, &end, 0); | |
260 | if(end == str) | |
dc764e50 | 261 | return -1; |
1da177e4 LT |
262 | *ptr = end; |
263 | } | |
97d88ac8 | 264 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
265 | n = *str - 'a'; |
266 | str++; | |
267 | *ptr = str; | |
268 | } | |
dc764e50 | 269 | return n; |
1da177e4 LT |
270 | } |
271 | ||
d8d7c28e PBG |
272 | /* If *index_out == -1 at exit, the passed option was a general one; |
273 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
274 | * should not be freed on exit. | |
275 | */ | |
f28169d2 | 276 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 277 | { |
7d314e34 | 278 | struct ubd *ubd_dev; |
1da177e4 LT |
279 | struct openflags flags = global_openflags; |
280 | char *backing_file; | |
b8831a1d | 281 | int n, err = 0, i; |
1da177e4 LT |
282 | |
283 | if(index_out) *index_out = -1; | |
284 | n = *str; | |
285 | if(n == '='){ | |
286 | char *end; | |
287 | int major; | |
288 | ||
289 | str++; | |
1da177e4 LT |
290 | if(!strcmp(str, "sync")){ |
291 | global_openflags = of_sync(global_openflags); | |
b8831a1d | 292 | goto out1; |
1da177e4 | 293 | } |
b8831a1d JD |
294 | |
295 | err = -EINVAL; | |
1da177e4 LT |
296 | major = simple_strtoul(str, &end, 0); |
297 | if((*end != '\0') || (end == str)){ | |
f28169d2 | 298 | *error_out = "Didn't parse major number"; |
b8831a1d | 299 | goto out1; |
1da177e4 LT |
300 | } |
301 | ||
f28169d2 | 302 | mutex_lock(&ubd_lock); |
792dd4fc | 303 | if (fake_major != UBD_MAJOR) { |
f28169d2 JD |
304 | *error_out = "Can't assign a fake major twice"; |
305 | goto out1; | |
306 | } | |
6c29256c | 307 | |
f28169d2 | 308 | fake_major = major; |
1da177e4 LT |
309 | |
310 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
311 | major); | |
f28169d2 JD |
312 | err = 0; |
313 | out1: | |
314 | mutex_unlock(&ubd_lock); | |
315 | return err; | |
1da177e4 LT |
316 | } |
317 | ||
318 | n = parse_unit(&str); | |
319 | if(n < 0){ | |
f28169d2 JD |
320 | *error_out = "Couldn't parse device number"; |
321 | return -EINVAL; | |
1da177e4 LT |
322 | } |
323 | if(n >= MAX_DEV){ | |
f28169d2 JD |
324 | *error_out = "Device number out of range"; |
325 | return 1; | |
1da177e4 LT |
326 | } |
327 | ||
f28169d2 | 328 | err = -EBUSY; |
d7fb2c38 | 329 | mutex_lock(&ubd_lock); |
1da177e4 | 330 | |
7d314e34 PBG |
331 | ubd_dev = &ubd_devs[n]; |
332 | if(ubd_dev->file != NULL){ | |
f28169d2 | 333 | *error_out = "Device is already configured"; |
1da177e4 LT |
334 | goto out; |
335 | } | |
336 | ||
337 | if (index_out) | |
338 | *index_out = n; | |
339 | ||
f28169d2 | 340 | err = -EINVAL; |
6c29256c | 341 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
342 | switch (*str) { |
343 | case 'r': | |
344 | flags.w = 0; | |
345 | break; | |
346 | case 's': | |
347 | flags.s = 1; | |
348 | break; | |
349 | case 'd': | |
7d314e34 | 350 | ubd_dev->no_cow = 1; |
1da177e4 | 351 | break; |
6c29256c | 352 | case 'c': |
7d314e34 | 353 | ubd_dev->shared = 1; |
6c29256c | 354 | break; |
1da177e4 LT |
355 | case '=': |
356 | str++; | |
357 | goto break_loop; | |
358 | default: | |
f28169d2 JD |
359 | *error_out = "Expected '=' or flag letter " |
360 | "(r, s, c, or d)"; | |
1da177e4 LT |
361 | goto out; |
362 | } | |
363 | str++; | |
364 | } | |
365 | ||
f28169d2 JD |
366 | if (*str == '=') |
367 | *error_out = "Too many flags specified"; | |
368 | else | |
369 | *error_out = "Missing '='"; | |
1da177e4 LT |
370 | goto out; |
371 | ||
372 | break_loop: | |
1da177e4 LT |
373 | backing_file = strchr(str, ','); |
374 | ||
f28169d2 | 375 | if (backing_file == NULL) |
1da177e4 | 376 | backing_file = strchr(str, ':'); |
1da177e4 | 377 | |
f28169d2 JD |
378 | if(backing_file != NULL){ |
379 | if(ubd_dev->no_cow){ | |
380 | *error_out = "Can't specify both 'd' and a cow file"; | |
381 | goto out; | |
382 | } | |
1da177e4 LT |
383 | else { |
384 | *backing_file = '\0'; | |
385 | backing_file++; | |
386 | } | |
387 | } | |
f28169d2 | 388 | err = 0; |
7d314e34 PBG |
389 | ubd_dev->file = str; |
390 | ubd_dev->cow.file = backing_file; | |
391 | ubd_dev->boot_openflags = flags; | |
1da177e4 | 392 | out: |
d7fb2c38 | 393 | mutex_unlock(&ubd_lock); |
f28169d2 | 394 | return err; |
1da177e4 LT |
395 | } |
396 | ||
397 | static int ubd_setup(char *str) | |
398 | { | |
f28169d2 JD |
399 | char *error; |
400 | int err; | |
401 | ||
402 | err = ubd_setup_common(str, NULL, &error); | |
403 | if(err) | |
404 | printk(KERN_ERR "Failed to initialize device with \"%s\" : " | |
405 | "%s\n", str, error); | |
406 | return 1; | |
1da177e4 LT |
407 | } |
408 | ||
409 | __setup("ubd", ubd_setup); | |
410 | __uml_help(ubd_setup, | |
411 | "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" | |
412 | " This is used to associate a device with a file in the underlying\n" | |
413 | " filesystem. When specifying two filenames, the first one is the\n" | |
414 | " COW name and the second is the backing file name. As separator you can\n" | |
415 | " use either a ':' or a ',': the first one allows writing things like;\n" | |
416 | " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" | |
417 | " while with a ',' the shell would not expand the 2nd '~'.\n" | |
f28169d2 | 418 | " When using only one filename, UML will detect whether to treat it like\n" |
1da177e4 LT |
419 | " a COW file or a backing file. To override this detection, add the 'd'\n" |
420 | " flag:\n" | |
421 | " ubd0d=BackingFile\n" | |
422 | " Usually, there is a filesystem in the file, but \n" | |
423 | " that's not required. Swap devices containing swap files can be\n" | |
424 | " specified like this. Also, a file which doesn't contain a\n" | |
425 | " filesystem can have its contents read in the virtual \n" | |
426 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
427 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
428 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
20ede453 JD |
429 | " an 's' will cause data to be written to disk on the host immediately.\n" |
430 | " 'c' will cause the device to be treated as being shared between multiple\n" | |
431 | " UMLs and file locking will be turned off - this is appropriate for a\n" | |
432 | " cluster filesystem and inappropriate at almost all other times.\n\n" | |
1da177e4 LT |
433 | ); |
434 | ||
8299ca5c | 435 | static int udb_setup(char *str) |
1da177e4 LT |
436 | { |
437 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
438 | "udb TYPO\n", str); | |
dc764e50 | 439 | return 1; |
1da177e4 LT |
440 | } |
441 | ||
442 | __setup("udb", udb_setup); | |
443 | __uml_help(udb_setup, | |
444 | "udb\n" | |
0894e27e JD |
445 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
446 | " to impossible to catch visually unless you specifically look for\n" | |
447 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
448 | " in the boot output.\n\n" |
449 | ); | |
450 | ||
165125e1 | 451 | static void do_ubd_request(struct request_queue * q); |
91acb21f JD |
452 | |
453 | /* Only changed by ubd_init, which is an initcall. */ | |
5dc62b1b | 454 | static int thread_fd = -1; |
a0044bdf JD |
455 | static LIST_HEAD(restart); |
456 | ||
2fe30a34 | 457 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 458 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 459 | static void ubd_handler(void) |
1da177e4 | 460 | { |
2adcec21 | 461 | struct io_thread_req *req; |
a0044bdf JD |
462 | struct ubd *ubd; |
463 | struct list_head *list, *next_ele; | |
464 | unsigned long flags; | |
91acb21f JD |
465 | int n; |
466 | ||
a0044bdf | 467 | while(1){ |
a6ea4cce JD |
468 | n = os_read_file(thread_fd, &req, |
469 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
470 | if(n != sizeof(req)){ |
471 | if(n == -EAGAIN) | |
472 | break; | |
473 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
474 | "err = %d\n", -n); | |
475 | return; | |
476 | } | |
62f96cb0 | 477 | |
4d6c84d9 | 478 | blk_end_request(req->req, 0, req->length); |
2adcec21 | 479 | kfree(req); |
a0044bdf | 480 | } |
62f96cb0 | 481 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
482 | |
483 | list_for_each_safe(list, next_ele, &restart){ | |
484 | ubd = container_of(list, struct ubd, restart); | |
485 | list_del_init(&ubd->restart); | |
486 | spin_lock_irqsave(&ubd->lock, flags); | |
487 | do_ubd_request(ubd->queue); | |
488 | spin_unlock_irqrestore(&ubd->lock, flags); | |
489 | } | |
1da177e4 LT |
490 | } |
491 | ||
7bea96fd | 492 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 493 | { |
91acb21f | 494 | ubd_handler(); |
dc764e50 | 495 | return IRQ_HANDLED; |
91acb21f | 496 | } |
09ace81c | 497 | |
91acb21f JD |
498 | /* Only changed by ubd_init, which is an initcall. */ |
499 | static int io_pid = -1; | |
09ace81c | 500 | |
5dc62b1b | 501 | static void kill_io_thread(void) |
91acb21f | 502 | { |
6c29256c | 503 | if(io_pid != -1) |
91acb21f | 504 | os_kill_process(io_pid, 1); |
09ace81c | 505 | } |
1da177e4 | 506 | |
91acb21f JD |
507 | __uml_exitcall(kill_io_thread); |
508 | ||
d8d7c28e | 509 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
510 | { |
511 | char *file; | |
512 | ||
7d314e34 | 513 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
dc764e50 | 514 | return os_file_size(file, size_out); |
1da177e4 LT |
515 | } |
516 | ||
5dc62b1b WC |
517 | static int read_cow_bitmap(int fd, void *buf, int offset, int len) |
518 | { | |
519 | int err; | |
520 | ||
521 | err = os_seek_file(fd, offset); | |
522 | if (err < 0) | |
523 | return err; | |
524 | ||
525 | err = os_read_file(fd, buf, len); | |
526 | if (err < 0) | |
527 | return err; | |
528 | ||
529 | return 0; | |
530 | } | |
531 | ||
532 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
533 | { | |
534 | unsigned long modtime; | |
535 | unsigned long long actual; | |
536 | int err; | |
537 | ||
538 | err = os_file_modtime(file, &modtime); | |
539 | if (err < 0) { | |
540 | printk(KERN_ERR "Failed to get modification time of backing " | |
541 | "file \"%s\", err = %d\n", file, -err); | |
542 | return err; | |
543 | } | |
544 | ||
545 | err = os_file_size(file, &actual); | |
546 | if (err < 0) { | |
547 | printk(KERN_ERR "Failed to get size of backing file \"%s\", " | |
548 | "err = %d\n", file, -err); | |
549 | return err; | |
550 | } | |
551 | ||
552 | if (actual != size) { | |
553 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
554 | * the typecast.*/ | |
555 | printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " | |
556 | "vs backing file\n", (unsigned long long) size, actual); | |
557 | return -EINVAL; | |
558 | } | |
559 | if (modtime != mtime) { | |
560 | printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " | |
561 | "backing file\n", mtime, modtime); | |
562 | return -EINVAL; | |
563 | } | |
564 | return 0; | |
565 | } | |
566 | ||
567 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) | |
568 | { | |
569 | struct uml_stat buf1, buf2; | |
570 | int err; | |
571 | ||
572 | if (from_cmdline == NULL) | |
573 | return 0; | |
574 | if (!strcmp(from_cmdline, from_cow)) | |
575 | return 0; | |
576 | ||
577 | err = os_stat_file(from_cmdline, &buf1); | |
578 | if (err < 0) { | |
579 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, | |
580 | -err); | |
581 | return 0; | |
582 | } | |
583 | err = os_stat_file(from_cow, &buf2); | |
584 | if (err < 0) { | |
585 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, | |
586 | -err); | |
587 | return 1; | |
588 | } | |
589 | if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
590 | return 0; | |
591 | ||
592 | printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " | |
593 | "\"%s\" specified in COW header of \"%s\"\n", | |
594 | from_cmdline, from_cow, cow); | |
595 | return 1; | |
596 | } | |
597 | ||
598 | static int open_ubd_file(char *file, struct openflags *openflags, int shared, | |
599 | char **backing_file_out, int *bitmap_offset_out, | |
600 | unsigned long *bitmap_len_out, int *data_offset_out, | |
601 | int *create_cow_out) | |
602 | { | |
603 | time_t mtime; | |
604 | unsigned long long size; | |
605 | __u32 version, align; | |
606 | char *backing_file; | |
607 | int fd, err, sectorsize, asked_switch, mode = 0644; | |
608 | ||
609 | fd = os_open_file(file, *openflags, mode); | |
610 | if (fd < 0) { | |
611 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
612 | *create_cow_out = 1; | |
613 | if (!openflags->w || | |
614 | ((fd != -EROFS) && (fd != -EACCES))) | |
615 | return fd; | |
616 | openflags->w = 0; | |
617 | fd = os_open_file(file, *openflags, mode); | |
618 | if (fd < 0) | |
619 | return fd; | |
620 | } | |
621 | ||
622 | if (shared) | |
623 | printk(KERN_INFO "Not locking \"%s\" on the host\n", file); | |
624 | else { | |
625 | err = os_lock_file(fd, openflags->w); | |
626 | if (err < 0) { | |
627 | printk(KERN_ERR "Failed to lock '%s', err = %d\n", | |
628 | file, -err); | |
629 | goto out_close; | |
630 | } | |
631 | } | |
632 | ||
633 | /* Successful return case! */ | |
634 | if (backing_file_out == NULL) | |
635 | return fd; | |
636 | ||
637 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
638 | &size, §orsize, &align, bitmap_offset_out); | |
639 | if (err && (*backing_file_out != NULL)) { | |
640 | printk(KERN_ERR "Failed to read COW header from COW file " | |
641 | "\"%s\", errno = %d\n", file, -err); | |
642 | goto out_close; | |
643 | } | |
644 | if (err) | |
645 | return fd; | |
646 | ||
647 | asked_switch = path_requires_switch(*backing_file_out, backing_file, | |
648 | file); | |
649 | ||
650 | /* Allow switching only if no mismatch. */ | |
651 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, | |
652 | mtime)) { | |
653 | printk(KERN_ERR "Switching backing file to '%s'\n", | |
654 | *backing_file_out); | |
655 | err = write_cow_header(file, fd, *backing_file_out, | |
656 | sectorsize, align, &size); | |
657 | if (err) { | |
658 | printk(KERN_ERR "Switch failed, errno = %d\n", -err); | |
659 | goto out_close; | |
660 | } | |
661 | } else { | |
662 | *backing_file_out = backing_file; | |
663 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
664 | if (err) | |
665 | goto out_close; | |
666 | } | |
667 | ||
668 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
669 | bitmap_len_out, data_offset_out); | |
670 | ||
671 | return fd; | |
672 | out_close: | |
673 | os_close_file(fd); | |
674 | return err; | |
675 | } | |
676 | ||
677 | static int create_cow_file(char *cow_file, char *backing_file, | |
678 | struct openflags flags, | |
679 | int sectorsize, int alignment, int *bitmap_offset_out, | |
680 | unsigned long *bitmap_len_out, int *data_offset_out) | |
681 | { | |
682 | int err, fd; | |
683 | ||
684 | flags.c = 1; | |
685 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); | |
686 | if (fd < 0) { | |
687 | err = fd; | |
688 | printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", | |
689 | cow_file, -err); | |
690 | goto out; | |
691 | } | |
692 | ||
693 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
694 | bitmap_offset_out, bitmap_len_out, | |
695 | data_offset_out); | |
696 | if (!err) | |
697 | return fd; | |
698 | os_close_file(fd); | |
699 | out: | |
700 | return err; | |
701 | } | |
702 | ||
5f75a4f8 | 703 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 704 | { |
7d314e34 PBG |
705 | os_close_file(ubd_dev->fd); |
706 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
707 | return; |
708 | ||
7d314e34 PBG |
709 | os_close_file(ubd_dev->cow.fd); |
710 | vfree(ubd_dev->cow.bitmap); | |
711 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
712 | } |
713 | ||
7d314e34 | 714 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
715 | { |
716 | struct openflags flags; | |
717 | char **back_ptr; | |
718 | int err, create_cow, *create_ptr; | |
0bf16bff | 719 | int fd; |
1da177e4 | 720 | |
7d314e34 | 721 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 722 | create_cow = 0; |
7d314e34 PBG |
723 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
724 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
725 | |
726 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
727 | back_ptr, &ubd_dev->cow.bitmap_offset, |
728 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 729 | create_ptr); |
1da177e4 | 730 | |
0bf16bff PBG |
731 | if((fd == -ENOENT) && create_cow){ |
732 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
733 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
734 | &ubd_dev->cow.bitmap_offset, | |
735 | &ubd_dev->cow.bitmap_len, | |
736 | &ubd_dev->cow.data_offset); | |
0bf16bff | 737 | if(fd >= 0){ |
1da177e4 | 738 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 739 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
740 | } |
741 | } | |
742 | ||
0bf16bff | 743 | if(fd < 0){ |
7d314e34 | 744 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
745 | -fd); |
746 | return fd; | |
1da177e4 | 747 | } |
0bf16bff | 748 | ubd_dev->fd = fd; |
1da177e4 | 749 | |
7d314e34 | 750 | if(ubd_dev->cow.file != NULL){ |
086fa5ff | 751 | blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); |
f4768ffd | 752 | |
1da177e4 | 753 | err = -ENOMEM; |
da2486ba | 754 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 755 | if(ubd_dev->cow.bitmap == NULL){ |
1da177e4 LT |
756 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
757 | goto error; | |
758 | } | |
759 | flush_tlb_kernel_vm(); | |
760 | ||
7d314e34 PBG |
761 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
762 | ubd_dev->cow.bitmap_offset, | |
763 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
764 | if(err < 0) |
765 | goto error; | |
766 | ||
7d314e34 | 767 | flags = ubd_dev->openflags; |
1da177e4 | 768 | flags.w = 0; |
7d314e34 | 769 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 770 | NULL, NULL, NULL, NULL); |
1da177e4 | 771 | if(err < 0) goto error; |
7d314e34 | 772 | ubd_dev->cow.fd = err; |
1da177e4 | 773 | } |
dc764e50 | 774 | return 0; |
1da177e4 | 775 | error: |
7d314e34 | 776 | os_close_file(ubd_dev->fd); |
dc764e50 | 777 | return err; |
1da177e4 LT |
778 | } |
779 | ||
2e3f5251 JD |
780 | static void ubd_device_release(struct device *dev) |
781 | { | |
8691b97b | 782 | struct ubd *ubd_dev = dev_get_drvdata(dev); |
2e3f5251 JD |
783 | |
784 | blk_cleanup_queue(ubd_dev->queue); | |
785 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
786 | } | |
787 | ||
5f75a4f8 | 788 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 789 | struct gendisk **disk_out) |
1da177e4 LT |
790 | { |
791 | struct gendisk *disk; | |
1da177e4 LT |
792 | |
793 | disk = alloc_disk(1 << UBD_SHIFT); | |
794 | if(disk == NULL) | |
dc764e50 | 795 | return -ENOMEM; |
1da177e4 LT |
796 | |
797 | disk->major = major; | |
798 | disk->first_minor = unit << UBD_SHIFT; | |
799 | disk->fops = &ubd_blops; | |
800 | set_capacity(disk, size / 512); | |
792dd4fc | 801 | if (major == UBD_MAJOR) |
1da177e4 | 802 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 803 | else |
1da177e4 | 804 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
805 | |
806 | /* sysfs register (not for ide fake devices) */ | |
792dd4fc | 807 | if (major == UBD_MAJOR) { |
7d314e34 PBG |
808 | ubd_devs[unit].pdev.id = unit; |
809 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 | 810 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
8691b97b | 811 | dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); |
7d314e34 PBG |
812 | platform_device_register(&ubd_devs[unit].pdev); |
813 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
814 | } |
815 | ||
7d314e34 | 816 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 817 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
818 | add_disk(disk); |
819 | ||
820 | *disk_out = disk; | |
821 | return 0; | |
822 | } | |
823 | ||
824 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
825 | ||
f28169d2 | 826 | static int ubd_add(int n, char **error_out) |
1da177e4 | 827 | { |
7d314e34 | 828 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 829 | int err = 0; |
1da177e4 | 830 | |
7d314e34 | 831 | if(ubd_dev->file == NULL) |
ec7cf783 | 832 | goto out; |
1da177e4 | 833 | |
7d314e34 | 834 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
835 | if(err < 0){ |
836 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 837 | goto out; |
f28169d2 | 838 | } |
1da177e4 | 839 | |
7d314e34 | 840 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 841 | |
a0044bdf | 842 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 843 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 844 | |
62f96cb0 JD |
845 | err = -ENOMEM; |
846 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
847 | if (ubd_dev->queue == NULL) { | |
848 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 849 | goto out; |
62f96cb0 JD |
850 | } |
851 | ubd_dev->queue->queuedata = ubd_dev; | |
852 | ||
8a78362c | 853 | blk_queue_max_segments(ubd_dev->queue, MAX_SG); |
792dd4fc | 854 | err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); |
62f96cb0 JD |
855 | if(err){ |
856 | *error_out = "Failed to register device"; | |
857 | goto out_cleanup; | |
858 | } | |
6c29256c | 859 | |
792dd4fc | 860 | if (fake_major != UBD_MAJOR) |
5f75a4f8 | 861 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 862 | &fake_gendisk[n]); |
1da177e4 | 863 | |
83380cc1 JD |
864 | /* |
865 | * Perhaps this should also be under the "if (fake_major)" above | |
866 | * using the fake_disk->disk_name | |
867 | */ | |
1da177e4 LT |
868 | if (fake_ide) |
869 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
870 | ||
ec7cf783 | 871 | err = 0; |
ec7cf783 JD |
872 | out: |
873 | return err; | |
62f96cb0 JD |
874 | |
875 | out_cleanup: | |
876 | blk_cleanup_queue(ubd_dev->queue); | |
877 | goto out; | |
1da177e4 LT |
878 | } |
879 | ||
f28169d2 | 880 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 881 | { |
e7f6552f | 882 | int n, ret; |
1da177e4 | 883 | |
f28169d2 JD |
884 | /* This string is possibly broken up and stored, so it's only |
885 | * freed if ubd_setup_common fails, or if only general options | |
886 | * were set. | |
887 | */ | |
970d6e3a | 888 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 889 | if (str == NULL) { |
f28169d2 JD |
890 | *error_out = "Failed to allocate memory"; |
891 | return -ENOMEM; | |
1da177e4 | 892 | } |
f28169d2 JD |
893 | |
894 | ret = ubd_setup_common(str, &n, error_out); | |
895 | if (ret) | |
e7f6552f | 896 | goto err_free; |
f28169d2 | 897 | |
e7f6552f PBG |
898 | if (n == -1) { |
899 | ret = 0; | |
d8d7c28e | 900 | goto err_free; |
1da177e4 | 901 | } |
1da177e4 | 902 | |
dc764e50 | 903 | mutex_lock(&ubd_lock); |
f28169d2 | 904 | ret = ubd_add(n, error_out); |
e7f6552f | 905 | if (ret) |
7d314e34 | 906 | ubd_devs[n].file = NULL; |
dc764e50 | 907 | mutex_unlock(&ubd_lock); |
1da177e4 | 908 | |
e7f6552f | 909 | out: |
dc764e50 | 910 | return ret; |
e7f6552f PBG |
911 | |
912 | err_free: | |
913 | kfree(str); | |
914 | goto out; | |
1da177e4 LT |
915 | } |
916 | ||
917 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
918 | { | |
7d314e34 | 919 | struct ubd *ubd_dev; |
1da177e4 LT |
920 | int n, len = 0; |
921 | ||
922 | n = parse_unit(&name); | |
923 | if((n >= MAX_DEV) || (n < 0)){ | |
924 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 925 | return -1; |
1da177e4 LT |
926 | } |
927 | ||
7d314e34 | 928 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 929 | mutex_lock(&ubd_lock); |
1da177e4 | 930 | |
7d314e34 | 931 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
932 | CONFIG_CHUNK(str, size, len, "", 1); |
933 | goto out; | |
934 | } | |
935 | ||
7d314e34 | 936 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 937 | |
7d314e34 | 938 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 939 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 940 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
941 | } |
942 | else CONFIG_CHUNK(str, size, len, "", 1); | |
943 | ||
944 | out: | |
d7fb2c38 | 945 | mutex_unlock(&ubd_lock); |
dc764e50 | 946 | return len; |
1da177e4 LT |
947 | } |
948 | ||
29d56cfe JD |
949 | static int ubd_id(char **str, int *start_out, int *end_out) |
950 | { | |
dc764e50 | 951 | int n; |
29d56cfe JD |
952 | |
953 | n = parse_unit(str); | |
dc764e50 JD |
954 | *start_out = 0; |
955 | *end_out = MAX_DEV - 1; | |
956 | return n; | |
29d56cfe JD |
957 | } |
958 | ||
f28169d2 | 959 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 960 | { |
2e3f5251 | 961 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 962 | struct ubd *ubd_dev; |
29d56cfe | 963 | int err = -ENODEV; |
1da177e4 | 964 | |
d7fb2c38 | 965 | mutex_lock(&ubd_lock); |
1da177e4 | 966 | |
7d314e34 | 967 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 968 | |
7d314e34 | 969 | if(ubd_dev->file == NULL) |
29d56cfe | 970 | goto out; |
1da177e4 | 971 | |
29d56cfe JD |
972 | /* you cannot remove a open disk */ |
973 | err = -EBUSY; | |
7d314e34 | 974 | if(ubd_dev->count > 0) |
1da177e4 LT |
975 | goto out; |
976 | ||
dc764e50 | 977 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
978 | if(disk != NULL){ |
979 | del_gendisk(disk); | |
980 | put_disk(disk); | |
981 | } | |
1da177e4 LT |
982 | |
983 | if(fake_gendisk[n] != NULL){ | |
984 | del_gendisk(fake_gendisk[n]); | |
985 | put_disk(fake_gendisk[n]); | |
986 | fake_gendisk[n] = NULL; | |
987 | } | |
988 | ||
1da177e4 | 989 | err = 0; |
2e3f5251 | 990 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 991 | out: |
d7fb2c38 | 992 | mutex_unlock(&ubd_lock); |
29d56cfe | 993 | return err; |
1da177e4 LT |
994 | } |
995 | ||
f28169d2 | 996 | /* All these are called by mconsole in process context and without |
b8831a1d | 997 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 998 | */ |
1da177e4 | 999 | static struct mc_device ubd_mc = { |
84f48d4f | 1000 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
1001 | .name = "ubd", |
1002 | .config = ubd_config, | |
dc764e50 | 1003 | .get_config = ubd_get_config, |
29d56cfe | 1004 | .id = ubd_id, |
1da177e4 LT |
1005 | .remove = ubd_remove, |
1006 | }; | |
1007 | ||
d8d7c28e | 1008 | static int __init ubd_mc_init(void) |
1da177e4 LT |
1009 | { |
1010 | mconsole_register_dev(&ubd_mc); | |
1011 | return 0; | |
1012 | } | |
1013 | ||
1014 | __initcall(ubd_mc_init); | |
1015 | ||
d8d7c28e PBG |
1016 | static int __init ubd0_init(void) |
1017 | { | |
1018 | struct ubd *ubd_dev = &ubd_devs[0]; | |
1019 | ||
b8831a1d | 1020 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
1021 | if(ubd_dev->file == NULL) |
1022 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
1023 | mutex_unlock(&ubd_lock); |
1024 | ||
dc764e50 | 1025 | return 0; |
d8d7c28e PBG |
1026 | } |
1027 | ||
1028 | __initcall(ubd0_init); | |
1029 | ||
b8831a1d | 1030 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
1031 | static struct platform_driver ubd_driver = { |
1032 | .driver = { | |
1033 | .name = DRIVER_NAME, | |
1034 | }, | |
1da177e4 LT |
1035 | }; |
1036 | ||
d8d7c28e | 1037 | static int __init ubd_init(void) |
1da177e4 | 1038 | { |
f28169d2 JD |
1039 | char *error; |
1040 | int i, err; | |
1da177e4 | 1041 | |
792dd4fc | 1042 | if (register_blkdev(UBD_MAJOR, "ubd")) |
1da177e4 LT |
1043 | return -1; |
1044 | ||
792dd4fc | 1045 | if (fake_major != UBD_MAJOR) { |
1da177e4 LT |
1046 | char name[sizeof("ubd_nnn\0")]; |
1047 | ||
1048 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
1049 | if (register_blkdev(fake_major, "ubd")) |
1050 | return -1; | |
1051 | } | |
3ae5eaec | 1052 | platform_driver_register(&ubd_driver); |
dc764e50 | 1053 | mutex_lock(&ubd_lock); |
f28169d2 JD |
1054 | for (i = 0; i < MAX_DEV; i++){ |
1055 | err = ubd_add(i, &error); | |
1056 | if(err) | |
1057 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
1058 | "%s\n", i, error); | |
1059 | } | |
dc764e50 | 1060 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
1061 | return 0; |
1062 | } | |
1063 | ||
1064 | late_initcall(ubd_init); | |
1065 | ||
d8d7c28e | 1066 | static int __init ubd_driver_init(void){ |
91acb21f JD |
1067 | unsigned long stack; |
1068 | int err; | |
1069 | ||
1070 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
1071 | if(global_openflags.s){ | |
1072 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
1073 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
1074 | * enough. So use anyway the io thread. */ | |
1075 | } | |
1076 | stack = alloc_stack(0, 0); | |
6c29256c | 1077 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
1078 | &thread_fd); |
1079 | if(io_pid < 0){ | |
6c29256c | 1080 | printk(KERN_ERR |
91acb21f JD |
1081 | "ubd : Failed to start I/O thread (errno = %d) - " |
1082 | "falling back to synchronous I/O\n", -io_pid); | |
1083 | io_pid = -1; | |
dc764e50 | 1084 | return 0; |
91acb21f | 1085 | } |
6c29256c | 1086 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 1087 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
1088 | if(err != 0) |
1089 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 1090 | return 0; |
91acb21f JD |
1091 | } |
1092 | ||
1093 | device_initcall(ubd_driver_init); | |
1094 | ||
a625c998 | 1095 | static int ubd_open(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1096 | { |
a625c998 | 1097 | struct gendisk *disk = bdev->bd_disk; |
7d314e34 | 1098 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
1099 | int err = 0; |
1100 | ||
7d314e34 PBG |
1101 | if(ubd_dev->count == 0){ |
1102 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
1103 | if(err){ |
1104 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 1105 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
1106 | goto out; |
1107 | } | |
1108 | } | |
7d314e34 PBG |
1109 | ubd_dev->count++; |
1110 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
1111 | |
1112 | /* This should no more be needed. And it didn't work anyway to exclude | |
1113 | * read-write remounting of filesystems.*/ | |
a625c998 | 1114 | /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 1115 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 1116 | err = -EROFS; |
2c49be99 | 1117 | }*/ |
1da177e4 | 1118 | out: |
dc764e50 | 1119 | return err; |
1da177e4 LT |
1120 | } |
1121 | ||
a625c998 | 1122 | static int ubd_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 1123 | { |
7d314e34 | 1124 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 1125 | |
7d314e34 | 1126 | if(--ubd_dev->count == 0) |
5f75a4f8 | 1127 | ubd_close_dev(ubd_dev); |
dc764e50 | 1128 | return 0; |
1da177e4 LT |
1129 | } |
1130 | ||
91acb21f JD |
1131 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
1132 | __u64 *cow_offset, unsigned long *bitmap, | |
1133 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
1134 | __u64 bitmap_len) | |
1da177e4 | 1135 | { |
91acb21f JD |
1136 | __u64 sector = io_offset >> 9; |
1137 | int i, update_bitmap = 0; | |
1138 | ||
1139 | for(i = 0; i < length >> 9; i++){ | |
1140 | if(cow_mask != NULL) | |
1141 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1142 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1143 | continue; | |
1da177e4 | 1144 | |
91acb21f JD |
1145 | update_bitmap = 1; |
1146 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1147 | } | |
1148 | ||
1149 | if(!update_bitmap) | |
1150 | return; | |
1da177e4 | 1151 | |
91acb21f | 1152 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1153 | |
91acb21f JD |
1154 | /* This takes care of the case where we're exactly at the end of the |
1155 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1156 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1157 | * for the original diagnosis. | |
1158 | */ | |
6d074242 JO |
1159 | if (*cow_offset == (DIV_ROUND_UP(bitmap_len, |
1160 | sizeof(unsigned long)) - 1)) | |
91acb21f JD |
1161 | (*cow_offset)--; |
1162 | ||
1163 | bitmap_words[0] = bitmap[*cow_offset]; | |
1164 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1165 | ||
1166 | *cow_offset *= sizeof(unsigned long); | |
1167 | *cow_offset += bitmap_offset; | |
1168 | } | |
1169 | ||
1170 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1171 | __u64 bitmap_offset, __u64 bitmap_len) | |
1172 | { | |
1173 | __u64 sector = req->offset >> 9; | |
1174 | int i; | |
1175 | ||
1176 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1177 | panic("Operation too long"); | |
1178 | ||
1179 | if(req->op == UBD_READ) { | |
1180 | for(i = 0; i < req->length >> 9; i++){ | |
1181 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1182 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1183 | &req->sector_mask); |
dc764e50 | 1184 | } |
91acb21f JD |
1185 | } |
1186 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1187 | &req->cow_offset, bitmap, bitmap_offset, | |
1188 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1189 | } |
1190 | ||
62f96cb0 | 1191 | /* Called with dev->lock held */ |
a0044bdf JD |
1192 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1193 | unsigned long long offset, int page_offset, | |
1194 | int len, struct page *page) | |
1da177e4 LT |
1195 | { |
1196 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1197 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1198 | |
62f96cb0 | 1199 | io_req->req = req; |
a0044bdf JD |
1200 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1201 | ubd_dev->fd; | |
7d314e34 | 1202 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1203 | io_req->cow_offset = -1; |
1da177e4 LT |
1204 | io_req->offset = offset; |
1205 | io_req->length = len; | |
1206 | io_req->error = 0; | |
91acb21f JD |
1207 | io_req->sector_mask = 0; |
1208 | ||
1209 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1210 | io_req->offsets[0] = 0; |
7d314e34 | 1211 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1212 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1213 | io_req->sectorsize = 1 << 9; |
1214 | ||
7d314e34 | 1215 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1216 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1217 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1218 | |
1da177e4 LT |
1219 | } |
1220 | ||
62f96cb0 | 1221 | /* Called with dev->lock held */ |
165125e1 | 1222 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1223 | { |
2adcec21 | 1224 | struct io_thread_req *io_req; |
1da177e4 | 1225 | struct request *req; |
f81f2f7c TH |
1226 | sector_t sector; |
1227 | int n; | |
a0044bdf JD |
1228 | |
1229 | while(1){ | |
2a9529a0 | 1230 | struct ubd *dev = q->queuedata; |
a0044bdf | 1231 | if(dev->end_sg == 0){ |
9934c8c0 | 1232 | struct request *req = blk_fetch_request(q); |
a0044bdf JD |
1233 | if(req == NULL) |
1234 | return; | |
1235 | ||
1236 | dev->request = req; | |
a0044bdf JD |
1237 | dev->start_sg = 0; |
1238 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1239 | } | |
1240 | ||
1241 | req = dev->request; | |
83096ebf | 1242 | sector = blk_rq_pos(req); |
a0044bdf JD |
1243 | while(dev->start_sg < dev->end_sg){ |
1244 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1245 | ||
2adcec21 | 1246 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1247 | GFP_ATOMIC); |
2adcec21 JD |
1248 | if(io_req == NULL){ |
1249 | if(list_empty(&dev->restart)) | |
1250 | list_add(&dev->restart, &restart); | |
1251 | return; | |
1252 | } | |
1253 | prepare_request(req, io_req, | |
f81f2f7c | 1254 | (unsigned long long)sector << 9, |
45711f1a | 1255 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1256 | |
f81f2f7c | 1257 | sector += sg->length >> 9; |
a6ea4cce JD |
1258 | n = os_write_file(thread_fd, &io_req, |
1259 | sizeof(struct io_thread_req *)); | |
2adcec21 | 1260 | if(n != sizeof(struct io_thread_req *)){ |
a0044bdf JD |
1261 | if(n != -EAGAIN) |
1262 | printk("write to io thread failed, " | |
1263 | "errno = %d\n", -n); | |
1264 | else if(list_empty(&dev->restart)) | |
1265 | list_add(&dev->restart, &restart); | |
12429bf9 | 1266 | kfree(io_req); |
a0044bdf JD |
1267 | return; |
1268 | } | |
1269 | ||
a0044bdf | 1270 | dev->start_sg++; |
1da177e4 | 1271 | } |
a0044bdf JD |
1272 | dev->end_sg = 0; |
1273 | dev->request = NULL; | |
1da177e4 LT |
1274 | } |
1275 | } | |
1276 | ||
a885c8c4 CH |
1277 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1278 | { | |
7d314e34 | 1279 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1280 | |
1281 | geo->heads = 128; | |
1282 | geo->sectors = 32; | |
7d314e34 | 1283 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1284 | return 0; |
1285 | } | |
1286 | ||
a625c998 | 1287 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 LT |
1288 | unsigned int cmd, unsigned long arg) |
1289 | { | |
a625c998 | 1290 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
73855e13 | 1291 | u16 ubd_id[ATA_ID_WORDS]; |
1da177e4 LT |
1292 | |
1293 | switch (cmd) { | |
1da177e4 | 1294 | struct cdrom_volctrl volume; |
1da177e4 | 1295 | case HDIO_GET_IDENTITY: |
73855e13 BZ |
1296 | memset(&ubd_id, 0, ATA_ID_WORDS * 2); |
1297 | ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); | |
1298 | ubd_id[ATA_ID_HEADS] = 128; | |
1299 | ubd_id[ATA_ID_SECTORS] = 32; | |
1da177e4 LT |
1300 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1301 | sizeof(ubd_id))) | |
dc764e50 JD |
1302 | return -EFAULT; |
1303 | return 0; | |
b8831a1d | 1304 | |
1da177e4 LT |
1305 | case CDROMVOLREAD: |
1306 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1307 | return -EFAULT; |
1da177e4 LT |
1308 | volume.channel0 = 255; |
1309 | volume.channel1 = 255; | |
1310 | volume.channel2 = 255; | |
1311 | volume.channel3 = 255; | |
1312 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1313 | return -EFAULT; |
1314 | return 0; | |
1da177e4 | 1315 | } |
dc764e50 | 1316 | return -EINVAL; |
1da177e4 LT |
1317 | } |
1318 | ||
91acb21f | 1319 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1320 | { |
91acb21f | 1321 | int n; |
1da177e4 | 1322 | |
91acb21f | 1323 | if(req->cow_offset == -1) |
dc764e50 | 1324 | return 0; |
1da177e4 | 1325 | |
91acb21f JD |
1326 | n = os_seek_file(req->fds[1], req->cow_offset); |
1327 | if(n < 0){ | |
1328 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
dc764e50 | 1329 | return 1; |
91acb21f | 1330 | } |
1da177e4 | 1331 | |
a6ea4cce JD |
1332 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1333 | sizeof(req->bitmap_words)); | |
91acb21f JD |
1334 | if(n != sizeof(req->bitmap_words)){ |
1335 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1336 | req->fds[1]); | |
dc764e50 | 1337 | return 1; |
91acb21f | 1338 | } |
1da177e4 | 1339 | |
dc764e50 | 1340 | return 0; |
91acb21f | 1341 | } |
1da177e4 | 1342 | |
5dc62b1b | 1343 | static void do_io(struct io_thread_req *req) |
91acb21f JD |
1344 | { |
1345 | char *buf; | |
1346 | unsigned long len; | |
1347 | int n, nsectors, start, end, bit; | |
1348 | int err; | |
1349 | __u64 off; | |
1350 | ||
1351 | nsectors = req->length / req->sectorsize; | |
1352 | start = 0; | |
1353 | do { | |
1354 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1355 | end = start; | |
1356 | while((end < nsectors) && | |
1357 | (ubd_test_bit(end, (unsigned char *) | |
1358 | &req->sector_mask) == bit)) | |
1359 | end++; | |
1360 | ||
1361 | off = req->offset + req->offsets[bit] + | |
1362 | start * req->sectorsize; | |
1363 | len = (end - start) * req->sectorsize; | |
1364 | buf = &req->buffer[start * req->sectorsize]; | |
1365 | ||
1366 | err = os_seek_file(req->fds[bit], off); | |
1367 | if(err < 0){ | |
1368 | printk("do_io - lseek failed : err = %d\n", -err); | |
1369 | req->error = 1; | |
1370 | return; | |
1371 | } | |
1372 | if(req->op == UBD_READ){ | |
1373 | n = 0; | |
1374 | do { | |
1375 | buf = &buf[n]; | |
1376 | len -= n; | |
a6ea4cce | 1377 | n = os_read_file(req->fds[bit], buf, len); |
91acb21f JD |
1378 | if (n < 0) { |
1379 | printk("do_io - read failed, err = %d " | |
1380 | "fd = %d\n", -n, req->fds[bit]); | |
1381 | req->error = 1; | |
1382 | return; | |
1383 | } | |
1384 | } while((n < len) && (n != 0)); | |
1385 | if (n < len) memset(&buf[n], 0, len - n); | |
1386 | } else { | |
a6ea4cce | 1387 | n = os_write_file(req->fds[bit], buf, len); |
91acb21f JD |
1388 | if(n != len){ |
1389 | printk("do_io - write failed err = %d " | |
1390 | "fd = %d\n", -n, req->fds[bit]); | |
1391 | req->error = 1; | |
1392 | return; | |
1393 | } | |
1394 | } | |
1395 | ||
1396 | start = end; | |
1397 | } while(start < nsectors); | |
1da177e4 | 1398 | |
91acb21f | 1399 | req->error = update_bitmap(req); |
1da177e4 | 1400 | } |
91acb21f JD |
1401 | |
1402 | /* Changed in start_io_thread, which is serialized by being called only | |
1403 | * from ubd_init, which is an initcall. | |
1404 | */ | |
1405 | int kernel_fd = -1; | |
1406 | ||
d8d7c28e PBG |
1407 | /* Only changed by the io thread. XXX: currently unused. */ |
1408 | static int io_count = 0; | |
91acb21f JD |
1409 | |
1410 | int io_thread(void *arg) | |
1411 | { | |
2adcec21 | 1412 | struct io_thread_req *req; |
91acb21f JD |
1413 | int n; |
1414 | ||
1415 | ignore_sigwinch_sig(); | |
1416 | while(1){ | |
a6ea4cce | 1417 | n = os_read_file(kernel_fd, &req, |
2adcec21 JD |
1418 | sizeof(struct io_thread_req *)); |
1419 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1420 | if(n < 0) |
1421 | printk("io_thread - read failed, fd = %d, " | |
1422 | "err = %d\n", kernel_fd, -n); | |
1423 | else { | |
1424 | printk("io_thread - short read, fd = %d, " | |
1425 | "length = %d\n", kernel_fd, n); | |
1426 | } | |
1427 | continue; | |
1428 | } | |
1429 | io_count++; | |
2adcec21 | 1430 | do_io(req); |
a6ea4cce | 1431 | n = os_write_file(kernel_fd, &req, |
2adcec21 JD |
1432 | sizeof(struct io_thread_req *)); |
1433 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1434 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1435 | kernel_fd, -n); | |
1436 | } | |
91acb21f | 1437 | |
1b57e9c2 JD |
1438 | return 0; |
1439 | } |