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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 | ||
20 | #define MAJOR_NR UBD_MAJOR | |
21 | #define UBD_SHIFT 4 | |
22 | ||
1da177e4 LT |
23 | #include "linux/module.h" |
24 | #include "linux/blkdev.h" | |
25 | #include "linux/hdreg.h" | |
26 | #include "linux/init.h" | |
1da177e4 LT |
27 | #include "linux/cdrom.h" |
28 | #include "linux/proc_fs.h" | |
29 | #include "linux/ctype.h" | |
30 | #include "linux/capability.h" | |
31 | #include "linux/mm.h" | |
32 | #include "linux/vmalloc.h" | |
33 | #include "linux/blkpg.h" | |
34 | #include "linux/genhd.h" | |
35 | #include "linux/spinlock.h" | |
d052d1be | 36 | #include "linux/platform_device.h" |
1da177e4 LT |
37 | #include "asm/segment.h" |
38 | #include "asm/uaccess.h" | |
39 | #include "asm/irq.h" | |
40 | #include "asm/types.h" | |
41 | #include "asm/tlbflush.h" | |
42 | #include "user_util.h" | |
43 | #include "mem_user.h" | |
44 | #include "kern_util.h" | |
45 | #include "kern.h" | |
46 | #include "mconsole_kern.h" | |
47 | #include "init.h" | |
48 | #include "irq_user.h" | |
49 | #include "irq_kern.h" | |
50 | #include "ubd_user.h" | |
1da177e4 LT |
51 | #include "os.h" |
52 | #include "mem.h" | |
53 | #include "mem_kern.h" | |
54 | #include "cow.h" | |
55 | ||
7b9014c1 | 56 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
57 | |
58 | struct io_thread_req { | |
62f96cb0 | 59 | struct request *req; |
91acb21f | 60 | enum ubd_req op; |
1da177e4 LT |
61 | int fds[2]; |
62 | unsigned long offsets[2]; | |
63 | unsigned long long offset; | |
64 | unsigned long length; | |
65 | char *buffer; | |
66 | int sectorsize; | |
91acb21f JD |
67 | unsigned long sector_mask; |
68 | unsigned long long cow_offset; | |
69 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
70 | int error; |
71 | }; | |
72 | ||
6c29256c | 73 | extern int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
74 | char **backing_file_out, int *bitmap_offset_out, |
75 | unsigned long *bitmap_len_out, int *data_offset_out, | |
76 | int *create_cow_out); | |
77 | extern int create_cow_file(char *cow_file, char *backing_file, | |
78 | struct openflags flags, int sectorsize, | |
79 | int alignment, int *bitmap_offset_out, | |
80 | unsigned long *bitmap_len_out, | |
81 | int *data_offset_out); | |
82 | extern int read_cow_bitmap(int fd, void *buf, int offset, int len); | |
91acb21f | 83 | extern void do_io(struct io_thread_req *req); |
1da177e4 | 84 | |
91acb21f | 85 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
86 | { |
87 | __u64 n; | |
88 | int bits, off; | |
89 | ||
91acb21f | 90 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
91 | n = bit / bits; |
92 | off = bit % bits; | |
91acb21f | 93 | return((data[n] & (1 << off)) != 0); |
1da177e4 LT |
94 | } |
95 | ||
91acb21f | 96 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
97 | { |
98 | __u64 n; | |
99 | int bits, off; | |
100 | ||
91acb21f | 101 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
102 | n = bit / bits; |
103 | off = bit % bits; | |
91acb21f | 104 | data[n] |= (1 << off); |
1da177e4 LT |
105 | } |
106 | /*End stuff from ubd_user.h*/ | |
107 | ||
108 | #define DRIVER_NAME "uml-blkdev" | |
109 | ||
d7fb2c38 | 110 | static DEFINE_MUTEX(ubd_lock); |
1da177e4 | 111 | |
2fe30a34 PBG |
112 | /* XXX - this made sense in 2.4 days, now it's only used as a boolean, and |
113 | * probably it doesn't make sense even for that. */ | |
114 | static int do_ubd; | |
91acb21f | 115 | |
1da177e4 LT |
116 | static int ubd_open(struct inode * inode, struct file * filp); |
117 | static int ubd_release(struct inode * inode, struct file * file); | |
118 | static int ubd_ioctl(struct inode * inode, struct file * file, | |
119 | unsigned int cmd, unsigned long arg); | |
a885c8c4 | 120 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 121 | |
97d88ac8 | 122 | #define MAX_DEV (16) |
1da177e4 | 123 | |
1da177e4 LT |
124 | static struct block_device_operations ubd_blops = { |
125 | .owner = THIS_MODULE, | |
126 | .open = ubd_open, | |
127 | .release = ubd_release, | |
128 | .ioctl = ubd_ioctl, | |
a885c8c4 | 129 | .getgeo = ubd_getgeo, |
1da177e4 LT |
130 | }; |
131 | ||
1da177e4 LT |
132 | /* Protected by ubd_lock */ |
133 | static int fake_major = MAJOR_NR; | |
134 | ||
135 | static struct gendisk *ubd_gendisk[MAX_DEV]; | |
136 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 137 | |
1da177e4 LT |
138 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
139 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
140 | .cl = 1 }) | |
141 | #else | |
142 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
143 | .cl = 1 }) | |
144 | #endif | |
145 | ||
146 | /* Not protected - changed only in ubd_setup_common and then only to | |
147 | * to enable O_SYNC. | |
148 | */ | |
149 | static struct openflags global_openflags = OPEN_FLAGS; | |
150 | ||
151 | struct cow { | |
2a9d32f6 | 152 | /* backing file name */ |
1da177e4 | 153 | char *file; |
2a9d32f6 | 154 | /* backing file fd */ |
1da177e4 LT |
155 | int fd; |
156 | unsigned long *bitmap; | |
157 | unsigned long bitmap_len; | |
158 | int bitmap_offset; | |
159 | int data_offset; | |
160 | }; | |
161 | ||
162 | struct ubd { | |
2a9d32f6 PBG |
163 | /* name (and fd, below) of the file opened for writing, either the |
164 | * backing or the cow file. */ | |
1da177e4 LT |
165 | char *file; |
166 | int count; | |
167 | int fd; | |
168 | __u64 size; | |
169 | struct openflags boot_openflags; | |
170 | struct openflags openflags; | |
84e945e3 PBG |
171 | unsigned shared:1; |
172 | unsigned no_cow:1; | |
1da177e4 LT |
173 | struct cow cow; |
174 | struct platform_device pdev; | |
62f96cb0 JD |
175 | struct request_queue *queue; |
176 | spinlock_t lock; | |
1da177e4 LT |
177 | }; |
178 | ||
179 | #define DEFAULT_COW { \ | |
180 | .file = NULL, \ | |
181 | .fd = -1, \ | |
182 | .bitmap = NULL, \ | |
183 | .bitmap_offset = 0, \ | |
184 | .data_offset = 0, \ | |
185 | } | |
186 | ||
187 | #define DEFAULT_UBD { \ | |
188 | .file = NULL, \ | |
189 | .count = 0, \ | |
190 | .fd = -1, \ | |
191 | .size = -1, \ | |
192 | .boot_openflags = OPEN_FLAGS, \ | |
193 | .openflags = OPEN_FLAGS, \ | |
194 | .no_cow = 0, \ | |
6c29256c | 195 | .shared = 0, \ |
1da177e4 | 196 | .cow = DEFAULT_COW, \ |
62f96cb0 | 197 | .lock = SPIN_LOCK_UNLOCKED, \ |
1da177e4 LT |
198 | } |
199 | ||
7d314e34 | 200 | struct ubd ubd_devs[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD }; |
1da177e4 | 201 | |
1da177e4 LT |
202 | /* Only changed by fake_ide_setup which is a setup */ |
203 | static int fake_ide = 0; | |
204 | static struct proc_dir_entry *proc_ide_root = NULL; | |
205 | static struct proc_dir_entry *proc_ide = NULL; | |
206 | ||
207 | static void make_proc_ide(void) | |
208 | { | |
209 | proc_ide_root = proc_mkdir("ide", NULL); | |
210 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
211 | } | |
212 | ||
213 | static int proc_ide_read_media(char *page, char **start, off_t off, int count, | |
214 | int *eof, void *data) | |
215 | { | |
216 | int len; | |
217 | ||
218 | strcpy(page, "disk\n"); | |
219 | len = strlen("disk\n"); | |
220 | len -= off; | |
221 | if (len < count){ | |
222 | *eof = 1; | |
223 | if (len <= 0) return 0; | |
224 | } | |
225 | else len = count; | |
226 | *start = page + off; | |
227 | return len; | |
228 | } | |
229 | ||
230 | static void make_ide_entries(char *dev_name) | |
231 | { | |
232 | struct proc_dir_entry *dir, *ent; | |
233 | char name[64]; | |
234 | ||
235 | if(proc_ide_root == NULL) make_proc_ide(); | |
236 | ||
237 | dir = proc_mkdir(dev_name, proc_ide); | |
238 | if(!dir) return; | |
239 | ||
240 | ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); | |
241 | if(!ent) return; | |
242 | ent->nlink = 1; | |
243 | ent->data = NULL; | |
244 | ent->read_proc = proc_ide_read_media; | |
245 | ent->write_proc = NULL; | |
246 | sprintf(name,"ide0/%s", dev_name); | |
247 | proc_symlink(dev_name, proc_ide_root, name); | |
248 | } | |
249 | ||
250 | static int fake_ide_setup(char *str) | |
251 | { | |
252 | fake_ide = 1; | |
253 | return(1); | |
254 | } | |
255 | ||
256 | __setup("fake_ide", fake_ide_setup); | |
257 | ||
258 | __uml_help(fake_ide_setup, | |
259 | "fake_ide\n" | |
260 | " Create ide0 entries that map onto ubd devices.\n\n" | |
261 | ); | |
262 | ||
263 | static int parse_unit(char **ptr) | |
264 | { | |
265 | char *str = *ptr, *end; | |
266 | int n = -1; | |
267 | ||
268 | if(isdigit(*str)) { | |
269 | n = simple_strtoul(str, &end, 0); | |
270 | if(end == str) | |
271 | return(-1); | |
272 | *ptr = end; | |
273 | } | |
97d88ac8 | 274 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
275 | n = *str - 'a'; |
276 | str++; | |
277 | *ptr = str; | |
278 | } | |
279 | return(n); | |
280 | } | |
281 | ||
d8d7c28e PBG |
282 | /* If *index_out == -1 at exit, the passed option was a general one; |
283 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
284 | * should not be freed on exit. | |
285 | */ | |
f28169d2 | 286 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 287 | { |
7d314e34 | 288 | struct ubd *ubd_dev; |
1da177e4 LT |
289 | struct openflags flags = global_openflags; |
290 | char *backing_file; | |
291 | int n, err, i; | |
292 | ||
293 | if(index_out) *index_out = -1; | |
294 | n = *str; | |
295 | if(n == '='){ | |
296 | char *end; | |
297 | int major; | |
298 | ||
299 | str++; | |
1da177e4 LT |
300 | if(!strcmp(str, "sync")){ |
301 | global_openflags = of_sync(global_openflags); | |
f28169d2 | 302 | return 0; |
1da177e4 LT |
303 | } |
304 | major = simple_strtoul(str, &end, 0); | |
305 | if((*end != '\0') || (end == str)){ | |
f28169d2 JD |
306 | *error_out = "Didn't parse major number"; |
307 | return -EINVAL; | |
1da177e4 LT |
308 | } |
309 | ||
f28169d2 JD |
310 | err = -EINVAL; |
311 | mutex_lock(&ubd_lock); | |
312 | if(fake_major != MAJOR_NR){ | |
313 | *error_out = "Can't assign a fake major twice"; | |
314 | goto out1; | |
315 | } | |
6c29256c | 316 | |
f28169d2 | 317 | fake_major = major; |
1da177e4 LT |
318 | |
319 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
320 | major); | |
f28169d2 JD |
321 | err = 0; |
322 | out1: | |
323 | mutex_unlock(&ubd_lock); | |
324 | return err; | |
1da177e4 LT |
325 | } |
326 | ||
327 | n = parse_unit(&str); | |
328 | if(n < 0){ | |
f28169d2 JD |
329 | *error_out = "Couldn't parse device number"; |
330 | return -EINVAL; | |
1da177e4 LT |
331 | } |
332 | if(n >= MAX_DEV){ | |
f28169d2 JD |
333 | *error_out = "Device number out of range"; |
334 | return 1; | |
1da177e4 LT |
335 | } |
336 | ||
f28169d2 | 337 | err = -EBUSY; |
d7fb2c38 | 338 | mutex_lock(&ubd_lock); |
1da177e4 | 339 | |
7d314e34 PBG |
340 | ubd_dev = &ubd_devs[n]; |
341 | if(ubd_dev->file != NULL){ | |
f28169d2 | 342 | *error_out = "Device is already configured"; |
1da177e4 LT |
343 | goto out; |
344 | } | |
345 | ||
346 | if (index_out) | |
347 | *index_out = n; | |
348 | ||
f28169d2 | 349 | err = -EINVAL; |
6c29256c | 350 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
351 | switch (*str) { |
352 | case 'r': | |
353 | flags.w = 0; | |
354 | break; | |
355 | case 's': | |
356 | flags.s = 1; | |
357 | break; | |
358 | case 'd': | |
7d314e34 | 359 | ubd_dev->no_cow = 1; |
1da177e4 | 360 | break; |
6c29256c | 361 | case 'c': |
7d314e34 | 362 | ubd_dev->shared = 1; |
6c29256c | 363 | break; |
1da177e4 LT |
364 | case '=': |
365 | str++; | |
366 | goto break_loop; | |
367 | default: | |
f28169d2 JD |
368 | *error_out = "Expected '=' or flag letter " |
369 | "(r, s, c, or d)"; | |
1da177e4 LT |
370 | goto out; |
371 | } | |
372 | str++; | |
373 | } | |
374 | ||
f28169d2 JD |
375 | if (*str == '=') |
376 | *error_out = "Too many flags specified"; | |
377 | else | |
378 | *error_out = "Missing '='"; | |
1da177e4 LT |
379 | goto out; |
380 | ||
381 | break_loop: | |
1da177e4 LT |
382 | backing_file = strchr(str, ','); |
383 | ||
f28169d2 | 384 | if (backing_file == NULL) |
1da177e4 | 385 | backing_file = strchr(str, ':'); |
1da177e4 | 386 | |
f28169d2 JD |
387 | if(backing_file != NULL){ |
388 | if(ubd_dev->no_cow){ | |
389 | *error_out = "Can't specify both 'd' and a cow file"; | |
390 | goto out; | |
391 | } | |
1da177e4 LT |
392 | else { |
393 | *backing_file = '\0'; | |
394 | backing_file++; | |
395 | } | |
396 | } | |
f28169d2 | 397 | err = 0; |
7d314e34 PBG |
398 | ubd_dev->file = str; |
399 | ubd_dev->cow.file = backing_file; | |
400 | ubd_dev->boot_openflags = flags; | |
1da177e4 | 401 | out: |
d7fb2c38 | 402 | mutex_unlock(&ubd_lock); |
f28169d2 | 403 | return err; |
1da177e4 LT |
404 | } |
405 | ||
406 | static int ubd_setup(char *str) | |
407 | { | |
f28169d2 JD |
408 | char *error; |
409 | int err; | |
410 | ||
411 | err = ubd_setup_common(str, NULL, &error); | |
412 | if(err) | |
413 | printk(KERN_ERR "Failed to initialize device with \"%s\" : " | |
414 | "%s\n", str, error); | |
415 | return 1; | |
1da177e4 LT |
416 | } |
417 | ||
418 | __setup("ubd", ubd_setup); | |
419 | __uml_help(ubd_setup, | |
420 | "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" | |
421 | " This is used to associate a device with a file in the underlying\n" | |
422 | " filesystem. When specifying two filenames, the first one is the\n" | |
423 | " COW name and the second is the backing file name. As separator you can\n" | |
424 | " use either a ':' or a ',': the first one allows writing things like;\n" | |
425 | " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" | |
426 | " while with a ',' the shell would not expand the 2nd '~'.\n" | |
f28169d2 | 427 | " When using only one filename, UML will detect whether to treat it like\n" |
1da177e4 LT |
428 | " a COW file or a backing file. To override this detection, add the 'd'\n" |
429 | " flag:\n" | |
430 | " ubd0d=BackingFile\n" | |
431 | " Usually, there is a filesystem in the file, but \n" | |
432 | " that's not required. Swap devices containing swap files can be\n" | |
433 | " specified like this. Also, a file which doesn't contain a\n" | |
434 | " filesystem can have its contents read in the virtual \n" | |
435 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
436 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
437 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
438 | " an 's' will cause data to be written to disk on the host immediately.\n\n" | |
439 | ); | |
440 | ||
441 | static int udb_setup(char *str) | |
442 | { | |
443 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
444 | "udb TYPO\n", str); | |
445 | return(1); | |
446 | } | |
447 | ||
448 | __setup("udb", udb_setup); | |
449 | __uml_help(udb_setup, | |
450 | "udb\n" | |
0894e27e JD |
451 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
452 | " to impossible to catch visually unless you specifically look for\n" | |
453 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
454 | " in the boot output.\n\n" |
455 | ); | |
456 | ||
457 | static int fakehd_set = 0; | |
458 | static int fakehd(char *str) | |
459 | { | |
460 | printk(KERN_INFO "fakehd : Changing ubd name to \"hd\".\n"); | |
461 | fakehd_set = 1; | |
462 | return 1; | |
463 | } | |
464 | ||
465 | __setup("fakehd", fakehd); | |
466 | __uml_help(fakehd, | |
467 | "fakehd\n" | |
468 | " Change the ubd device name to \"hd\".\n\n" | |
469 | ); | |
470 | ||
471 | static void do_ubd_request(request_queue_t * q); | |
91acb21f JD |
472 | |
473 | /* Only changed by ubd_init, which is an initcall. */ | |
474 | int thread_fd = -1; | |
1da177e4 LT |
475 | |
476 | /* Changed by ubd_handler, which is serialized because interrupts only | |
477 | * happen on CPU 0. | |
d8d7c28e | 478 | * XXX: currently unused. |
1da177e4 | 479 | */ |
d8d7c28e | 480 | static int intr_count = 0; |
1da177e4 | 481 | |
91acb21f JD |
482 | /* call ubd_finish if you need to serialize */ |
483 | static void __ubd_finish(struct request *req, int error) | |
1da177e4 | 484 | { |
91acb21f JD |
485 | int nsect; |
486 | ||
487 | if(error){ | |
488 | end_request(req, 0); | |
489 | return; | |
1da177e4 | 490 | } |
91acb21f JD |
491 | nsect = req->current_nr_sectors; |
492 | req->sector += nsect; | |
493 | req->buffer += nsect << 9; | |
494 | req->errors = 0; | |
495 | req->nr_sectors -= nsect; | |
496 | req->current_nr_sectors = 0; | |
497 | end_request(req, 1); | |
1da177e4 LT |
498 | } |
499 | ||
33f775ee PBG |
500 | /* Callable only from interrupt context - otherwise you need to do |
501 | * spin_lock_irq()/spin_lock_irqsave() */ | |
91acb21f | 502 | static inline void ubd_finish(struct request *req, int error) |
1da177e4 | 503 | { |
62f96cb0 JD |
504 | struct ubd *dev = req->rq_disk->private_data; |
505 | ||
506 | spin_lock(&dev->lock); | |
91acb21f | 507 | __ubd_finish(req, error); |
62f96cb0 | 508 | spin_unlock(&dev->lock); |
1da177e4 LT |
509 | } |
510 | ||
2fe30a34 | 511 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 512 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 513 | static void ubd_handler(void) |
1da177e4 | 514 | { |
91acb21f | 515 | struct io_thread_req req; |
62f96cb0 JD |
516 | struct request *rq; |
517 | struct ubd *dev; | |
91acb21f JD |
518 | int n; |
519 | ||
2fe30a34 | 520 | do_ubd = 0; |
91acb21f JD |
521 | intr_count++; |
522 | n = os_read_file(thread_fd, &req, sizeof(req)); | |
523 | if(n != sizeof(req)){ | |
524 | printk(KERN_ERR "Pid %d - spurious interrupt in ubd_handler, " | |
525 | "err = %d\n", os_getpid(), -n); | |
91acb21f JD |
526 | return; |
527 | } | |
6c29256c | 528 | |
62f96cb0 JD |
529 | rq = req.req; |
530 | dev = rq->rq_disk->private_data; | |
531 | ||
91acb21f | 532 | ubd_finish(rq, req.error); |
62f96cb0 JD |
533 | reactivate_fd(thread_fd, UBD_IRQ); |
534 | spin_lock(&dev->lock); | |
535 | do_ubd_request(dev->queue); | |
536 | spin_unlock(&dev->lock); | |
1da177e4 LT |
537 | } |
538 | ||
7bea96fd | 539 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 540 | { |
91acb21f JD |
541 | ubd_handler(); |
542 | return(IRQ_HANDLED); | |
543 | } | |
09ace81c | 544 | |
91acb21f JD |
545 | /* Only changed by ubd_init, which is an initcall. */ |
546 | static int io_pid = -1; | |
09ace81c | 547 | |
91acb21f JD |
548 | void kill_io_thread(void) |
549 | { | |
6c29256c | 550 | if(io_pid != -1) |
91acb21f | 551 | os_kill_process(io_pid, 1); |
09ace81c | 552 | } |
1da177e4 | 553 | |
91acb21f JD |
554 | __uml_exitcall(kill_io_thread); |
555 | ||
d8d7c28e | 556 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
557 | { |
558 | char *file; | |
559 | ||
7d314e34 | 560 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
1da177e4 LT |
561 | return(os_file_size(file, size_out)); |
562 | } | |
563 | ||
5f75a4f8 | 564 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 565 | { |
7d314e34 PBG |
566 | os_close_file(ubd_dev->fd); |
567 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
568 | return; |
569 | ||
7d314e34 PBG |
570 | os_close_file(ubd_dev->cow.fd); |
571 | vfree(ubd_dev->cow.bitmap); | |
572 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
573 | } |
574 | ||
7d314e34 | 575 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
576 | { |
577 | struct openflags flags; | |
578 | char **back_ptr; | |
579 | int err, create_cow, *create_ptr; | |
0bf16bff | 580 | int fd; |
1da177e4 | 581 | |
7d314e34 | 582 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 583 | create_cow = 0; |
7d314e34 PBG |
584 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
585 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
586 | |
587 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
588 | back_ptr, &ubd_dev->cow.bitmap_offset, |
589 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 590 | create_ptr); |
1da177e4 | 591 | |
0bf16bff PBG |
592 | if((fd == -ENOENT) && create_cow){ |
593 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
594 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
595 | &ubd_dev->cow.bitmap_offset, | |
596 | &ubd_dev->cow.bitmap_len, | |
597 | &ubd_dev->cow.data_offset); | |
0bf16bff | 598 | if(fd >= 0){ |
1da177e4 | 599 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 600 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
601 | } |
602 | } | |
603 | ||
0bf16bff | 604 | if(fd < 0){ |
7d314e34 | 605 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
606 | -fd); |
607 | return fd; | |
1da177e4 | 608 | } |
0bf16bff | 609 | ubd_dev->fd = fd; |
1da177e4 | 610 | |
7d314e34 | 611 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 612 | err = -ENOMEM; |
7d314e34 PBG |
613 | ubd_dev->cow.bitmap = (void *) vmalloc(ubd_dev->cow.bitmap_len); |
614 | if(ubd_dev->cow.bitmap == NULL){ | |
1da177e4 LT |
615 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
616 | goto error; | |
617 | } | |
618 | flush_tlb_kernel_vm(); | |
619 | ||
7d314e34 PBG |
620 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
621 | ubd_dev->cow.bitmap_offset, | |
622 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
623 | if(err < 0) |
624 | goto error; | |
625 | ||
7d314e34 | 626 | flags = ubd_dev->openflags; |
1da177e4 | 627 | flags.w = 0; |
7d314e34 | 628 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 629 | NULL, NULL, NULL, NULL); |
1da177e4 | 630 | if(err < 0) goto error; |
7d314e34 | 631 | ubd_dev->cow.fd = err; |
1da177e4 LT |
632 | } |
633 | return(0); | |
634 | error: | |
7d314e34 | 635 | os_close_file(ubd_dev->fd); |
1da177e4 LT |
636 | return(err); |
637 | } | |
638 | ||
5f75a4f8 | 639 | static int ubd_disk_register(int major, u64 size, int unit, |
1da177e4 LT |
640 | struct gendisk **disk_out) |
641 | ||
642 | { | |
643 | struct gendisk *disk; | |
1da177e4 LT |
644 | |
645 | disk = alloc_disk(1 << UBD_SHIFT); | |
646 | if(disk == NULL) | |
647 | return(-ENOMEM); | |
648 | ||
649 | disk->major = major; | |
650 | disk->first_minor = unit << UBD_SHIFT; | |
651 | disk->fops = &ubd_blops; | |
652 | set_capacity(disk, size / 512); | |
ce7b0f46 | 653 | if(major == MAJOR_NR) |
1da177e4 | 654 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 655 | else |
1da177e4 | 656 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
657 | |
658 | /* sysfs register (not for ide fake devices) */ | |
659 | if (major == MAJOR_NR) { | |
7d314e34 PBG |
660 | ubd_devs[unit].pdev.id = unit; |
661 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
662 | platform_device_register(&ubd_devs[unit].pdev); | |
663 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
664 | } |
665 | ||
7d314e34 | 666 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 667 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
668 | add_disk(disk); |
669 | ||
670 | *disk_out = disk; | |
671 | return 0; | |
672 | } | |
673 | ||
674 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
675 | ||
f28169d2 | 676 | static int ubd_add(int n, char **error_out) |
1da177e4 | 677 | { |
7d314e34 | 678 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 679 | int err = 0; |
1da177e4 | 680 | |
7d314e34 | 681 | if(ubd_dev->file == NULL) |
ec7cf783 | 682 | goto out; |
1da177e4 | 683 | |
7d314e34 | 684 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
685 | if(err < 0){ |
686 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 687 | goto out; |
f28169d2 | 688 | } |
1da177e4 | 689 | |
7d314e34 | 690 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 691 | |
62f96cb0 JD |
692 | err = -ENOMEM; |
693 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
694 | if (ubd_dev->queue == NULL) { | |
695 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 696 | goto out; |
62f96cb0 JD |
697 | } |
698 | ubd_dev->queue->queuedata = ubd_dev; | |
699 | ||
700 | err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); | |
701 | if(err){ | |
702 | *error_out = "Failed to register device"; | |
703 | goto out_cleanup; | |
704 | } | |
6c29256c | 705 | |
1da177e4 | 706 | if(fake_major != MAJOR_NR) |
5f75a4f8 | 707 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 708 | &fake_gendisk[n]); |
1da177e4 LT |
709 | |
710 | /* perhaps this should also be under the "if (fake_major)" above */ | |
711 | /* using the fake_disk->disk_name and also the fakehd_set name */ | |
712 | if (fake_ide) | |
713 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
714 | ||
ec7cf783 | 715 | err = 0; |
ec7cf783 JD |
716 | out: |
717 | return err; | |
62f96cb0 JD |
718 | |
719 | out_cleanup: | |
720 | blk_cleanup_queue(ubd_dev->queue); | |
721 | goto out; | |
1da177e4 LT |
722 | } |
723 | ||
f28169d2 | 724 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 725 | { |
e7f6552f | 726 | int n, ret; |
1da177e4 | 727 | |
f28169d2 JD |
728 | /* This string is possibly broken up and stored, so it's only |
729 | * freed if ubd_setup_common fails, or if only general options | |
730 | * were set. | |
731 | */ | |
970d6e3a | 732 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 733 | if (str == NULL) { |
f28169d2 JD |
734 | *error_out = "Failed to allocate memory"; |
735 | return -ENOMEM; | |
1da177e4 | 736 | } |
f28169d2 JD |
737 | |
738 | ret = ubd_setup_common(str, &n, error_out); | |
739 | if (ret) | |
e7f6552f | 740 | goto err_free; |
f28169d2 | 741 | |
e7f6552f PBG |
742 | if (n == -1) { |
743 | ret = 0; | |
d8d7c28e | 744 | goto err_free; |
1da177e4 | 745 | } |
1da177e4 | 746 | |
d7fb2c38 | 747 | mutex_lock(&ubd_lock); |
f28169d2 | 748 | ret = ubd_add(n, error_out); |
e7f6552f | 749 | if (ret) |
7d314e34 | 750 | ubd_devs[n].file = NULL; |
d7fb2c38 | 751 | mutex_unlock(&ubd_lock); |
1da177e4 | 752 | |
e7f6552f PBG |
753 | out: |
754 | return ret; | |
755 | ||
756 | err_free: | |
757 | kfree(str); | |
758 | goto out; | |
1da177e4 LT |
759 | } |
760 | ||
761 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
762 | { | |
7d314e34 | 763 | struct ubd *ubd_dev; |
1da177e4 LT |
764 | int n, len = 0; |
765 | ||
766 | n = parse_unit(&name); | |
767 | if((n >= MAX_DEV) || (n < 0)){ | |
768 | *error_out = "ubd_get_config : device number out of range"; | |
769 | return(-1); | |
770 | } | |
771 | ||
7d314e34 | 772 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 773 | mutex_lock(&ubd_lock); |
1da177e4 | 774 | |
7d314e34 | 775 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
776 | CONFIG_CHUNK(str, size, len, "", 1); |
777 | goto out; | |
778 | } | |
779 | ||
7d314e34 | 780 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 781 | |
7d314e34 | 782 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 783 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 784 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
785 | } |
786 | else CONFIG_CHUNK(str, size, len, "", 1); | |
787 | ||
788 | out: | |
d7fb2c38 | 789 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
790 | return(len); |
791 | } | |
792 | ||
29d56cfe JD |
793 | static int ubd_id(char **str, int *start_out, int *end_out) |
794 | { | |
795 | int n; | |
796 | ||
797 | n = parse_unit(str); | |
798 | *start_out = 0; | |
799 | *end_out = MAX_DEV - 1; | |
800 | return n; | |
801 | } | |
802 | ||
f28169d2 | 803 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 804 | { |
7d314e34 | 805 | struct ubd *ubd_dev; |
29d56cfe | 806 | int err = -ENODEV; |
1da177e4 | 807 | |
d7fb2c38 | 808 | mutex_lock(&ubd_lock); |
1da177e4 | 809 | |
29d56cfe JD |
810 | if(ubd_gendisk[n] == NULL) |
811 | goto out; | |
1da177e4 | 812 | |
7d314e34 | 813 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 814 | |
7d314e34 | 815 | if(ubd_dev->file == NULL) |
29d56cfe | 816 | goto out; |
1da177e4 | 817 | |
29d56cfe JD |
818 | /* you cannot remove a open disk */ |
819 | err = -EBUSY; | |
7d314e34 | 820 | if(ubd_dev->count > 0) |
1da177e4 LT |
821 | goto out; |
822 | ||
823 | del_gendisk(ubd_gendisk[n]); | |
824 | put_disk(ubd_gendisk[n]); | |
825 | ubd_gendisk[n] = NULL; | |
826 | ||
827 | if(fake_gendisk[n] != NULL){ | |
828 | del_gendisk(fake_gendisk[n]); | |
829 | put_disk(fake_gendisk[n]); | |
830 | fake_gendisk[n] = NULL; | |
831 | } | |
832 | ||
62f96cb0 | 833 | blk_cleanup_queue(ubd_dev->queue); |
7d314e34 PBG |
834 | platform_device_unregister(&ubd_dev->pdev); |
835 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
1da177e4 | 836 | err = 0; |
29d56cfe | 837 | out: |
d7fb2c38 | 838 | mutex_unlock(&ubd_lock); |
29d56cfe | 839 | return err; |
1da177e4 LT |
840 | } |
841 | ||
f28169d2 JD |
842 | /* All these are called by mconsole in process context and without |
843 | * ubd-specific locks. | |
844 | */ | |
1da177e4 | 845 | static struct mc_device ubd_mc = { |
84f48d4f | 846 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
847 | .name = "ubd", |
848 | .config = ubd_config, | |
849 | .get_config = ubd_get_config, | |
29d56cfe | 850 | .id = ubd_id, |
1da177e4 LT |
851 | .remove = ubd_remove, |
852 | }; | |
853 | ||
d8d7c28e | 854 | static int __init ubd_mc_init(void) |
1da177e4 LT |
855 | { |
856 | mconsole_register_dev(&ubd_mc); | |
857 | return 0; | |
858 | } | |
859 | ||
860 | __initcall(ubd_mc_init); | |
861 | ||
d8d7c28e PBG |
862 | static int __init ubd0_init(void) |
863 | { | |
864 | struct ubd *ubd_dev = &ubd_devs[0]; | |
865 | ||
866 | if(ubd_dev->file == NULL) | |
867 | ubd_dev->file = "root_fs"; | |
868 | return(0); | |
869 | } | |
870 | ||
871 | __initcall(ubd0_init); | |
872 | ||
3ae5eaec RK |
873 | static struct platform_driver ubd_driver = { |
874 | .driver = { | |
875 | .name = DRIVER_NAME, | |
876 | }, | |
1da177e4 LT |
877 | }; |
878 | ||
d8d7c28e | 879 | static int __init ubd_init(void) |
1da177e4 | 880 | { |
f28169d2 JD |
881 | char *error; |
882 | int i, err; | |
1da177e4 | 883 | |
1da177e4 LT |
884 | if (register_blkdev(MAJOR_NR, "ubd")) |
885 | return -1; | |
886 | ||
1da177e4 LT |
887 | if (fake_major != MAJOR_NR) { |
888 | char name[sizeof("ubd_nnn\0")]; | |
889 | ||
890 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
891 | if (register_blkdev(fake_major, "ubd")) |
892 | return -1; | |
893 | } | |
3ae5eaec | 894 | platform_driver_register(&ubd_driver); |
f28169d2 JD |
895 | for (i = 0; i < MAX_DEV; i++){ |
896 | err = ubd_add(i, &error); | |
897 | if(err) | |
898 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
899 | "%s\n", i, error); | |
900 | } | |
1da177e4 LT |
901 | return 0; |
902 | } | |
903 | ||
904 | late_initcall(ubd_init); | |
905 | ||
d8d7c28e | 906 | static int __init ubd_driver_init(void){ |
91acb21f JD |
907 | unsigned long stack; |
908 | int err; | |
909 | ||
910 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
911 | if(global_openflags.s){ | |
912 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
913 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
914 | * enough. So use anyway the io thread. */ | |
915 | } | |
916 | stack = alloc_stack(0, 0); | |
6c29256c | 917 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
918 | &thread_fd); |
919 | if(io_pid < 0){ | |
6c29256c | 920 | printk(KERN_ERR |
91acb21f JD |
921 | "ubd : Failed to start I/O thread (errno = %d) - " |
922 | "falling back to synchronous I/O\n", -io_pid); | |
923 | io_pid = -1; | |
924 | return(0); | |
925 | } | |
6c29256c | 926 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 927 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
928 | if(err != 0) |
929 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 930 | return 0; |
91acb21f JD |
931 | } |
932 | ||
933 | device_initcall(ubd_driver_init); | |
934 | ||
1da177e4 LT |
935 | static int ubd_open(struct inode *inode, struct file *filp) |
936 | { | |
937 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 938 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
939 | int err = 0; |
940 | ||
7d314e34 PBG |
941 | if(ubd_dev->count == 0){ |
942 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
943 | if(err){ |
944 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 945 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
946 | goto out; |
947 | } | |
948 | } | |
7d314e34 PBG |
949 | ubd_dev->count++; |
950 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
951 | |
952 | /* This should no more be needed. And it didn't work anyway to exclude | |
953 | * read-write remounting of filesystems.*/ | |
7d314e34 | 954 | /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 955 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 956 | err = -EROFS; |
2c49be99 | 957 | }*/ |
1da177e4 LT |
958 | out: |
959 | return(err); | |
960 | } | |
961 | ||
962 | static int ubd_release(struct inode * inode, struct file * file) | |
963 | { | |
964 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 965 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 966 | |
7d314e34 | 967 | if(--ubd_dev->count == 0) |
5f75a4f8 | 968 | ubd_close_dev(ubd_dev); |
1da177e4 LT |
969 | return(0); |
970 | } | |
971 | ||
91acb21f JD |
972 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
973 | __u64 *cow_offset, unsigned long *bitmap, | |
974 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
975 | __u64 bitmap_len) | |
1da177e4 | 976 | { |
91acb21f JD |
977 | __u64 sector = io_offset >> 9; |
978 | int i, update_bitmap = 0; | |
979 | ||
980 | for(i = 0; i < length >> 9; i++){ | |
981 | if(cow_mask != NULL) | |
982 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
983 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
984 | continue; | |
1da177e4 | 985 | |
91acb21f JD |
986 | update_bitmap = 1; |
987 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
988 | } | |
989 | ||
990 | if(!update_bitmap) | |
991 | return; | |
1da177e4 | 992 | |
91acb21f | 993 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 994 | |
91acb21f JD |
995 | /* This takes care of the case where we're exactly at the end of the |
996 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
997 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
998 | * for the original diagnosis. | |
999 | */ | |
1000 | if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / | |
1001 | sizeof(unsigned long) - 1)) | |
1002 | (*cow_offset)--; | |
1003 | ||
1004 | bitmap_words[0] = bitmap[*cow_offset]; | |
1005 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1006 | ||
1007 | *cow_offset *= sizeof(unsigned long); | |
1008 | *cow_offset += bitmap_offset; | |
1009 | } | |
1010 | ||
1011 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1012 | __u64 bitmap_offset, __u64 bitmap_len) | |
1013 | { | |
1014 | __u64 sector = req->offset >> 9; | |
1015 | int i; | |
1016 | ||
1017 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1018 | panic("Operation too long"); | |
1019 | ||
1020 | if(req->op == UBD_READ) { | |
1021 | for(i = 0; i < req->length >> 9; i++){ | |
1022 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1023 | ubd_set_bit(i, (unsigned char *) |
91acb21f JD |
1024 | &req->sector_mask); |
1025 | } | |
1026 | } | |
1027 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1028 | &req->cow_offset, bitmap, bitmap_offset, | |
1029 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1030 | } |
1031 | ||
62f96cb0 | 1032 | /* Called with dev->lock held */ |
91acb21f | 1033 | static int prepare_request(struct request *req, struct io_thread_req *io_req) |
1da177e4 LT |
1034 | { |
1035 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1036 | struct ubd *ubd_dev = disk->private_data; |
91acb21f JD |
1037 | __u64 offset; |
1038 | int len; | |
1039 | ||
2c49be99 | 1040 | /* This should be impossible now */ |
7d314e34 | 1041 | if((rq_data_dir(req) == WRITE) && !ubd_dev->openflags.w){ |
6c29256c | 1042 | printk("Write attempted on readonly ubd device %s\n", |
1da177e4 | 1043 | disk->disk_name); |
91acb21f | 1044 | end_request(req, 0); |
1da177e4 LT |
1045 | return(1); |
1046 | } | |
1047 | ||
91acb21f JD |
1048 | offset = ((__u64) req->sector) << 9; |
1049 | len = req->current_nr_sectors << 9; | |
1050 | ||
62f96cb0 | 1051 | io_req->req = req; |
7d314e34 PBG |
1052 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : ubd_dev->fd; |
1053 | io_req->fds[1] = ubd_dev->fd; | |
91acb21f | 1054 | io_req->cow_offset = -1; |
1da177e4 LT |
1055 | io_req->offset = offset; |
1056 | io_req->length = len; | |
1057 | io_req->error = 0; | |
91acb21f JD |
1058 | io_req->sector_mask = 0; |
1059 | ||
1060 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1061 | io_req->offsets[0] = 0; |
7d314e34 | 1062 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
91acb21f | 1063 | io_req->buffer = req->buffer; |
1da177e4 LT |
1064 | io_req->sectorsize = 1 << 9; |
1065 | ||
7d314e34 PBG |
1066 | if(ubd_dev->cow.file != NULL) |
1067 | cowify_req(io_req, ubd_dev->cow.bitmap, ubd_dev->cow.bitmap_offset, | |
1068 | ubd_dev->cow.bitmap_len); | |
91acb21f | 1069 | |
1da177e4 LT |
1070 | return(0); |
1071 | } | |
1072 | ||
62f96cb0 | 1073 | /* Called with dev->lock held */ |
1da177e4 LT |
1074 | static void do_ubd_request(request_queue_t *q) |
1075 | { | |
1076 | struct io_thread_req io_req; | |
1077 | struct request *req; | |
91acb21f JD |
1078 | int err, n; |
1079 | ||
1080 | if(thread_fd == -1){ | |
1081 | while((req = elv_next_request(q)) != NULL){ | |
1082 | err = prepare_request(req, &io_req); | |
1083 | if(!err){ | |
1084 | do_io(&io_req); | |
1085 | __ubd_finish(req, io_req.error); | |
1086 | } | |
1087 | } | |
1088 | } | |
1089 | else { | |
1090 | if(do_ubd || (req = elv_next_request(q)) == NULL) | |
1091 | return; | |
1092 | err = prepare_request(req, &io_req); | |
1093 | if(!err){ | |
2fe30a34 | 1094 | do_ubd = 1; |
91acb21f JD |
1095 | n = os_write_file(thread_fd, (char *) &io_req, |
1096 | sizeof(io_req)); | |
1097 | if(n != sizeof(io_req)) | |
1098 | printk("write to io thread failed, " | |
1099 | "errno = %d\n", -n); | |
1da177e4 LT |
1100 | } |
1101 | } | |
1102 | } | |
1103 | ||
a885c8c4 CH |
1104 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1105 | { | |
7d314e34 | 1106 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1107 | |
1108 | geo->heads = 128; | |
1109 | geo->sectors = 32; | |
7d314e34 | 1110 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1111 | return 0; |
1112 | } | |
1113 | ||
1da177e4 LT |
1114 | static int ubd_ioctl(struct inode * inode, struct file * file, |
1115 | unsigned int cmd, unsigned long arg) | |
1116 | { | |
7d314e34 | 1117 | struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; |
1da177e4 LT |
1118 | struct hd_driveid ubd_id = { |
1119 | .cyls = 0, | |
1120 | .heads = 128, | |
1121 | .sectors = 32, | |
1122 | }; | |
1123 | ||
1124 | switch (cmd) { | |
1da177e4 | 1125 | struct cdrom_volctrl volume; |
1da177e4 | 1126 | case HDIO_GET_IDENTITY: |
7d314e34 | 1127 | ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); |
1da177e4 LT |
1128 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1129 | sizeof(ubd_id))) | |
1130 | return(-EFAULT); | |
1131 | return(0); | |
1132 | ||
1133 | case CDROMVOLREAD: | |
1134 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
1135 | return(-EFAULT); | |
1136 | volume.channel0 = 255; | |
1137 | volume.channel1 = 255; | |
1138 | volume.channel2 = 255; | |
1139 | volume.channel3 = 255; | |
1140 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
1141 | return(-EFAULT); | |
1142 | return(0); | |
1143 | } | |
1144 | return(-EINVAL); | |
1145 | } | |
1146 | ||
4833aff7 | 1147 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) |
1da177e4 LT |
1148 | { |
1149 | struct uml_stat buf1, buf2; | |
1150 | int err; | |
1151 | ||
4833aff7 PBG |
1152 | if(from_cmdline == NULL) |
1153 | return 0; | |
1154 | if(!strcmp(from_cmdline, from_cow)) | |
1155 | return 0; | |
1da177e4 LT |
1156 | |
1157 | err = os_stat_file(from_cmdline, &buf1); | |
1158 | if(err < 0){ | |
1159 | printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); | |
4833aff7 | 1160 | return 0; |
1da177e4 LT |
1161 | } |
1162 | err = os_stat_file(from_cow, &buf2); | |
1163 | if(err < 0){ | |
1164 | printk("Couldn't stat '%s', err = %d\n", from_cow, -err); | |
4833aff7 | 1165 | return 1; |
1da177e4 LT |
1166 | } |
1167 | if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
4833aff7 | 1168 | return 0; |
1da177e4 LT |
1169 | |
1170 | printk("Backing file mismatch - \"%s\" requested,\n" | |
1171 | "\"%s\" specified in COW header of \"%s\"\n", | |
1172 | from_cmdline, from_cow, cow); | |
4833aff7 | 1173 | return 1; |
1da177e4 LT |
1174 | } |
1175 | ||
1176 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
1177 | { | |
1178 | unsigned long modtime; | |
fe1db50c | 1179 | unsigned long long actual; |
1da177e4 LT |
1180 | int err; |
1181 | ||
1182 | err = os_file_modtime(file, &modtime); | |
1183 | if(err < 0){ | |
1184 | printk("Failed to get modification time of backing file " | |
1185 | "\"%s\", err = %d\n", file, -err); | |
1186 | return(err); | |
1187 | } | |
1188 | ||
1189 | err = os_file_size(file, &actual); | |
1190 | if(err < 0){ | |
1191 | printk("Failed to get size of backing file \"%s\", " | |
1192 | "err = %d\n", file, -err); | |
1193 | return(err); | |
1194 | } | |
1195 | ||
1196 | if(actual != size){ | |
1197 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
1198 | * the typecast.*/ | |
1199 | printk("Size mismatch (%llu vs %llu) of COW header vs backing " | |
1200 | "file\n", (unsigned long long) size, actual); | |
1201 | return(-EINVAL); | |
1202 | } | |
1203 | if(modtime != mtime){ | |
1204 | printk("mtime mismatch (%ld vs %ld) of COW header vs backing " | |
1205 | "file\n", mtime, modtime); | |
1206 | return(-EINVAL); | |
1207 | } | |
1208 | return(0); | |
1209 | } | |
1210 | ||
1211 | int read_cow_bitmap(int fd, void *buf, int offset, int len) | |
1212 | { | |
1213 | int err; | |
1214 | ||
1215 | err = os_seek_file(fd, offset); | |
1216 | if(err < 0) | |
1217 | return(err); | |
1218 | ||
1219 | err = os_read_file(fd, buf, len); | |
1220 | if(err < 0) | |
1221 | return(err); | |
1222 | ||
1223 | return(0); | |
1224 | } | |
1225 | ||
6c29256c | 1226 | int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
1227 | char **backing_file_out, int *bitmap_offset_out, |
1228 | unsigned long *bitmap_len_out, int *data_offset_out, | |
1229 | int *create_cow_out) | |
1230 | { | |
1231 | time_t mtime; | |
1232 | unsigned long long size; | |
1233 | __u32 version, align; | |
1234 | char *backing_file; | |
4833aff7 | 1235 | int fd, err, sectorsize, asked_switch, mode = 0644; |
1da177e4 LT |
1236 | |
1237 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1238 | if (fd < 0) { |
1239 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
1da177e4 | 1240 | *create_cow_out = 1; |
a374a48f PBG |
1241 | if (!openflags->w || |
1242 | ((fd != -EROFS) && (fd != -EACCES))) | |
1243 | return fd; | |
1da177e4 LT |
1244 | openflags->w = 0; |
1245 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1246 | if (fd < 0) |
1247 | return fd; | |
1da177e4 LT |
1248 | } |
1249 | ||
6c29256c JD |
1250 | if(shared) |
1251 | printk("Not locking \"%s\" on the host\n", file); | |
1252 | else { | |
1253 | err = os_lock_file(fd, openflags->w); | |
1254 | if(err < 0){ | |
1255 | printk("Failed to lock '%s', err = %d\n", file, -err); | |
1256 | goto out_close; | |
1257 | } | |
1da177e4 LT |
1258 | } |
1259 | ||
d6e05edc | 1260 | /* Successful return case! */ |
a374a48f PBG |
1261 | if(backing_file_out == NULL) |
1262 | return(fd); | |
1da177e4 LT |
1263 | |
1264 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
1265 | &size, §orsize, &align, bitmap_offset_out); | |
1266 | if(err && (*backing_file_out != NULL)){ | |
1267 | printk("Failed to read COW header from COW file \"%s\", " | |
1268 | "errno = %d\n", file, -err); | |
1269 | goto out_close; | |
1270 | } | |
a374a48f PBG |
1271 | if(err) |
1272 | return(fd); | |
1da177e4 | 1273 | |
4833aff7 | 1274 | asked_switch = path_requires_switch(*backing_file_out, backing_file, file); |
1da177e4 | 1275 | |
4833aff7 PBG |
1276 | /* Allow switching only if no mismatch. */ |
1277 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) { | |
1da177e4 LT |
1278 | printk("Switching backing file to '%s'\n", *backing_file_out); |
1279 | err = write_cow_header(file, fd, *backing_file_out, | |
1280 | sectorsize, align, &size); | |
a374a48f | 1281 | if (err) { |
1da177e4 | 1282 | printk("Switch failed, errno = %d\n", -err); |
4833aff7 | 1283 | goto out_close; |
1da177e4 | 1284 | } |
a374a48f | 1285 | } else { |
1da177e4 LT |
1286 | *backing_file_out = backing_file; |
1287 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
a374a48f PBG |
1288 | if (err) |
1289 | goto out_close; | |
1da177e4 LT |
1290 | } |
1291 | ||
1292 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
1293 | bitmap_len_out, data_offset_out); | |
1294 | ||
a374a48f | 1295 | return fd; |
1da177e4 LT |
1296 | out_close: |
1297 | os_close_file(fd); | |
a374a48f | 1298 | return err; |
1da177e4 LT |
1299 | } |
1300 | ||
1301 | int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, | |
1302 | int sectorsize, int alignment, int *bitmap_offset_out, | |
1303 | unsigned long *bitmap_len_out, int *data_offset_out) | |
1304 | { | |
1305 | int err, fd; | |
1306 | ||
1307 | flags.c = 1; | |
6c29256c | 1308 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); |
1da177e4 LT |
1309 | if(fd < 0){ |
1310 | err = fd; | |
1311 | printk("Open of COW file '%s' failed, errno = %d\n", cow_file, | |
1312 | -err); | |
1313 | goto out; | |
1314 | } | |
1315 | ||
1316 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
1317 | bitmap_offset_out, bitmap_len_out, | |
1318 | data_offset_out); | |
1319 | if(!err) | |
1320 | return(fd); | |
1321 | os_close_file(fd); | |
1322 | out: | |
1323 | return(err); | |
1324 | } | |
1325 | ||
91acb21f | 1326 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1327 | { |
91acb21f | 1328 | int n; |
1da177e4 | 1329 | |
91acb21f JD |
1330 | if(req->cow_offset == -1) |
1331 | return(0); | |
1da177e4 | 1332 | |
91acb21f JD |
1333 | n = os_seek_file(req->fds[1], req->cow_offset); |
1334 | if(n < 0){ | |
1335 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
1336 | return(1); | |
1337 | } | |
1da177e4 | 1338 | |
91acb21f JD |
1339 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1340 | sizeof(req->bitmap_words)); | |
1341 | if(n != sizeof(req->bitmap_words)){ | |
1342 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1343 | req->fds[1]); | |
1344 | return(1); | |
1345 | } | |
1da177e4 | 1346 | |
91acb21f JD |
1347 | return(0); |
1348 | } | |
1da177e4 | 1349 | |
91acb21f JD |
1350 | void do_io(struct io_thread_req *req) |
1351 | { | |
1352 | char *buf; | |
1353 | unsigned long len; | |
1354 | int n, nsectors, start, end, bit; | |
1355 | int err; | |
1356 | __u64 off; | |
1357 | ||
1358 | nsectors = req->length / req->sectorsize; | |
1359 | start = 0; | |
1360 | do { | |
1361 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1362 | end = start; | |
1363 | while((end < nsectors) && | |
1364 | (ubd_test_bit(end, (unsigned char *) | |
1365 | &req->sector_mask) == bit)) | |
1366 | end++; | |
1367 | ||
1368 | off = req->offset + req->offsets[bit] + | |
1369 | start * req->sectorsize; | |
1370 | len = (end - start) * req->sectorsize; | |
1371 | buf = &req->buffer[start * req->sectorsize]; | |
1372 | ||
1373 | err = os_seek_file(req->fds[bit], off); | |
1374 | if(err < 0){ | |
1375 | printk("do_io - lseek failed : err = %d\n", -err); | |
1376 | req->error = 1; | |
1377 | return; | |
1378 | } | |
1379 | if(req->op == UBD_READ){ | |
1380 | n = 0; | |
1381 | do { | |
1382 | buf = &buf[n]; | |
1383 | len -= n; | |
1384 | n = os_read_file(req->fds[bit], buf, len); | |
1385 | if (n < 0) { | |
1386 | printk("do_io - read failed, err = %d " | |
1387 | "fd = %d\n", -n, req->fds[bit]); | |
1388 | req->error = 1; | |
1389 | return; | |
1390 | } | |
1391 | } while((n < len) && (n != 0)); | |
1392 | if (n < len) memset(&buf[n], 0, len - n); | |
1393 | } else { | |
1394 | n = os_write_file(req->fds[bit], buf, len); | |
1395 | if(n != len){ | |
1396 | printk("do_io - write failed err = %d " | |
1397 | "fd = %d\n", -n, req->fds[bit]); | |
1398 | req->error = 1; | |
1399 | return; | |
1400 | } | |
1401 | } | |
1402 | ||
1403 | start = end; | |
1404 | } while(start < nsectors); | |
1da177e4 | 1405 | |
91acb21f | 1406 | req->error = update_bitmap(req); |
1da177e4 | 1407 | } |
91acb21f JD |
1408 | |
1409 | /* Changed in start_io_thread, which is serialized by being called only | |
1410 | * from ubd_init, which is an initcall. | |
1411 | */ | |
1412 | int kernel_fd = -1; | |
1413 | ||
d8d7c28e PBG |
1414 | /* Only changed by the io thread. XXX: currently unused. */ |
1415 | static int io_count = 0; | |
91acb21f JD |
1416 | |
1417 | int io_thread(void *arg) | |
1418 | { | |
1419 | struct io_thread_req req; | |
1420 | int n; | |
1421 | ||
1422 | ignore_sigwinch_sig(); | |
1423 | while(1){ | |
1424 | n = os_read_file(kernel_fd, &req, sizeof(req)); | |
1425 | if(n != sizeof(req)){ | |
1426 | if(n < 0) | |
1427 | printk("io_thread - read failed, fd = %d, " | |
1428 | "err = %d\n", kernel_fd, -n); | |
1429 | else { | |
1430 | printk("io_thread - short read, fd = %d, " | |
1431 | "length = %d\n", kernel_fd, n); | |
1432 | } | |
1433 | continue; | |
1434 | } | |
1435 | io_count++; | |
1436 | do_io(&req); | |
1437 | n = os_write_file(kernel_fd, &req, sizeof(req)); | |
1438 | if(n != sizeof(req)) | |
1439 | printk("io_thread - write failed, fd = %d, err = %d\n", | |
1440 | kernel_fd, -n); | |
1441 | } | |
91acb21f | 1442 | |
1b57e9c2 JD |
1443 | return 0; |
1444 | } |