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 | ||
20 | #define MAJOR_NR UBD_MAJOR | |
21 | #define UBD_SHIFT 4 | |
22 | ||
e16f5350 | 23 | #include "linux/kernel.h" |
1da177e4 LT |
24 | #include "linux/module.h" |
25 | #include "linux/blkdev.h" | |
26 | #include "linux/hdreg.h" | |
27 | #include "linux/init.h" | |
1da177e4 LT |
28 | #include "linux/cdrom.h" |
29 | #include "linux/proc_fs.h" | |
30 | #include "linux/ctype.h" | |
31 | #include "linux/capability.h" | |
32 | #include "linux/mm.h" | |
33 | #include "linux/vmalloc.h" | |
34 | #include "linux/blkpg.h" | |
35 | #include "linux/genhd.h" | |
36 | #include "linux/spinlock.h" | |
d052d1be | 37 | #include "linux/platform_device.h" |
23464ffa | 38 | #include "linux/scatterlist.h" |
1da177e4 LT |
39 | #include "asm/segment.h" |
40 | #include "asm/uaccess.h" | |
41 | #include "asm/irq.h" | |
42 | #include "asm/types.h" | |
43 | #include "asm/tlbflush.h" | |
1da177e4 LT |
44 | #include "mem_user.h" |
45 | #include "kern_util.h" | |
46 | #include "kern.h" | |
47 | #include "mconsole_kern.h" | |
48 | #include "init.h" | |
49 | #include "irq_user.h" | |
50 | #include "irq_kern.h" | |
51 | #include "ubd_user.h" | |
edea1385 | 52 | #include "kern_util.h" |
1da177e4 LT |
53 | #include "os.h" |
54 | #include "mem.h" | |
55 | #include "mem_kern.h" | |
56 | #include "cow.h" | |
57 | ||
7b9014c1 | 58 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
59 | |
60 | struct io_thread_req { | |
62f96cb0 | 61 | struct request *req; |
91acb21f | 62 | enum ubd_req op; |
1da177e4 LT |
63 | int fds[2]; |
64 | unsigned long offsets[2]; | |
65 | unsigned long long offset; | |
66 | unsigned long length; | |
67 | char *buffer; | |
68 | int sectorsize; | |
91acb21f JD |
69 | unsigned long sector_mask; |
70 | unsigned long long cow_offset; | |
71 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
72 | int error; |
73 | }; | |
74 | ||
91acb21f | 75 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
76 | { |
77 | __u64 n; | |
78 | int bits, off; | |
79 | ||
91acb21f | 80 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
81 | n = bit / bits; |
82 | off = bit % bits; | |
dc764e50 | 83 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
84 | } |
85 | ||
91acb21f | 86 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
87 | { |
88 | __u64 n; | |
89 | int bits, off; | |
90 | ||
91acb21f | 91 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
92 | n = bit / bits; |
93 | off = bit % bits; | |
91acb21f | 94 | data[n] |= (1 << off); |
1da177e4 LT |
95 | } |
96 | /*End stuff from ubd_user.h*/ | |
97 | ||
98 | #define DRIVER_NAME "uml-blkdev" | |
99 | ||
d7fb2c38 | 100 | static DEFINE_MUTEX(ubd_lock); |
1da177e4 | 101 | |
1da177e4 LT |
102 | static int ubd_open(struct inode * inode, struct file * filp); |
103 | static int ubd_release(struct inode * inode, struct file * file); | |
104 | static int ubd_ioctl(struct inode * inode, struct file * file, | |
105 | unsigned int cmd, unsigned long arg); | |
a885c8c4 | 106 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 107 | |
97d88ac8 | 108 | #define MAX_DEV (16) |
1da177e4 | 109 | |
1da177e4 LT |
110 | static struct block_device_operations ubd_blops = { |
111 | .owner = THIS_MODULE, | |
112 | .open = ubd_open, | |
113 | .release = ubd_release, | |
114 | .ioctl = ubd_ioctl, | |
a885c8c4 | 115 | .getgeo = ubd_getgeo, |
1da177e4 LT |
116 | }; |
117 | ||
1da177e4 LT |
118 | /* Protected by ubd_lock */ |
119 | static int fake_major = MAJOR_NR; | |
1da177e4 LT |
120 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
121 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 122 | |
1da177e4 LT |
123 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
124 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
125 | .cl = 1 }) | |
126 | #else | |
127 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
128 | .cl = 1 }) | |
129 | #endif | |
1da177e4 LT |
130 | static struct openflags global_openflags = OPEN_FLAGS; |
131 | ||
132 | struct cow { | |
2a9d32f6 | 133 | /* backing file name */ |
1da177e4 | 134 | char *file; |
2a9d32f6 | 135 | /* backing file fd */ |
1da177e4 LT |
136 | int fd; |
137 | unsigned long *bitmap; | |
138 | unsigned long bitmap_len; | |
139 | int bitmap_offset; | |
dc764e50 | 140 | int data_offset; |
1da177e4 LT |
141 | }; |
142 | ||
a0044bdf JD |
143 | #define MAX_SG 64 |
144 | ||
1da177e4 | 145 | struct ubd { |
a0044bdf | 146 | struct list_head restart; |
2a9d32f6 PBG |
147 | /* name (and fd, below) of the file opened for writing, either the |
148 | * backing or the cow file. */ | |
1da177e4 LT |
149 | char *file; |
150 | int count; | |
151 | int fd; | |
152 | __u64 size; | |
153 | struct openflags boot_openflags; | |
154 | struct openflags openflags; | |
84e945e3 PBG |
155 | unsigned shared:1; |
156 | unsigned no_cow:1; | |
1da177e4 LT |
157 | struct cow cow; |
158 | struct platform_device pdev; | |
62f96cb0 JD |
159 | struct request_queue *queue; |
160 | spinlock_t lock; | |
a0044bdf JD |
161 | struct scatterlist sg[MAX_SG]; |
162 | struct request *request; | |
163 | int start_sg, end_sg; | |
1da177e4 LT |
164 | }; |
165 | ||
166 | #define DEFAULT_COW { \ | |
167 | .file = NULL, \ | |
dc764e50 JD |
168 | .fd = -1, \ |
169 | .bitmap = NULL, \ | |
1da177e4 | 170 | .bitmap_offset = 0, \ |
dc764e50 | 171 | .data_offset = 0, \ |
1da177e4 LT |
172 | } |
173 | ||
174 | #define DEFAULT_UBD { \ | |
175 | .file = NULL, \ | |
176 | .count = 0, \ | |
177 | .fd = -1, \ | |
178 | .size = -1, \ | |
179 | .boot_openflags = OPEN_FLAGS, \ | |
180 | .openflags = OPEN_FLAGS, \ | |
dc764e50 | 181 | .no_cow = 0, \ |
6c29256c | 182 | .shared = 0, \ |
dc764e50 | 183 | .cow = DEFAULT_COW, \ |
62f96cb0 | 184 | .lock = SPIN_LOCK_UNLOCKED, \ |
a0044bdf JD |
185 | .request = NULL, \ |
186 | .start_sg = 0, \ | |
187 | .end_sg = 0, \ | |
1da177e4 LT |
188 | } |
189 | ||
b8831a1d | 190 | /* Protected by ubd_lock */ |
5dc62b1b | 191 | static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; |
1da177e4 | 192 | |
1da177e4 LT |
193 | /* Only changed by fake_ide_setup which is a setup */ |
194 | static int fake_ide = 0; | |
195 | static struct proc_dir_entry *proc_ide_root = NULL; | |
196 | static struct proc_dir_entry *proc_ide = NULL; | |
197 | ||
198 | static void make_proc_ide(void) | |
199 | { | |
200 | proc_ide_root = proc_mkdir("ide", NULL); | |
201 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
202 | } | |
203 | ||
204 | static int proc_ide_read_media(char *page, char **start, off_t off, int count, | |
205 | int *eof, void *data) | |
206 | { | |
207 | int len; | |
208 | ||
209 | strcpy(page, "disk\n"); | |
210 | len = strlen("disk\n"); | |
211 | len -= off; | |
212 | if (len < count){ | |
213 | *eof = 1; | |
214 | if (len <= 0) return 0; | |
215 | } | |
216 | else len = count; | |
217 | *start = page + off; | |
218 | return len; | |
219 | } | |
220 | ||
c0a9290e | 221 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
222 | { |
223 | struct proc_dir_entry *dir, *ent; | |
224 | char name[64]; | |
225 | ||
226 | if(proc_ide_root == NULL) make_proc_ide(); | |
227 | ||
228 | dir = proc_mkdir(dev_name, proc_ide); | |
229 | if(!dir) return; | |
230 | ||
231 | ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); | |
232 | if(!ent) return; | |
1da177e4 LT |
233 | ent->data = NULL; |
234 | ent->read_proc = proc_ide_read_media; | |
235 | ent->write_proc = NULL; | |
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 JD |
302 | mutex_lock(&ubd_lock); |
303 | if(fake_major != MAJOR_NR){ | |
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; |
1da177e4 | 455 | |
4898b53a | 456 | static void ubd_end_request(struct request *req, int bytes, int error) |
1da177e4 | 457 | { |
4898b53a | 458 | blk_end_request(req, error, bytes); |
1da177e4 LT |
459 | } |
460 | ||
33f775ee PBG |
461 | /* Callable only from interrupt context - otherwise you need to do |
462 | * spin_lock_irq()/spin_lock_irqsave() */ | |
a0044bdf | 463 | static inline void ubd_finish(struct request *req, int bytes) |
1da177e4 | 464 | { |
a0044bdf | 465 | if(bytes < 0){ |
4898b53a | 466 | ubd_end_request(req, 0, -EIO); |
a0044bdf JD |
467 | return; |
468 | } | |
4898b53a | 469 | ubd_end_request(req, bytes, 0); |
1da177e4 LT |
470 | } |
471 | ||
a0044bdf JD |
472 | static LIST_HEAD(restart); |
473 | ||
2fe30a34 | 474 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 475 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 476 | static void ubd_handler(void) |
1da177e4 | 477 | { |
2adcec21 | 478 | struct io_thread_req *req; |
62f96cb0 | 479 | struct request *rq; |
a0044bdf JD |
480 | struct ubd *ubd; |
481 | struct list_head *list, *next_ele; | |
482 | unsigned long flags; | |
91acb21f JD |
483 | int n; |
484 | ||
a0044bdf | 485 | while(1){ |
a6ea4cce JD |
486 | n = os_read_file(thread_fd, &req, |
487 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
488 | if(n != sizeof(req)){ |
489 | if(n == -EAGAIN) | |
490 | break; | |
491 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
492 | "err = %d\n", -n); | |
493 | return; | |
494 | } | |
62f96cb0 | 495 | |
2adcec21 JD |
496 | rq = req->req; |
497 | rq->nr_sectors -= req->length >> 9; | |
a0044bdf JD |
498 | if(rq->nr_sectors == 0) |
499 | ubd_finish(rq, rq->hard_nr_sectors << 9); | |
2adcec21 | 500 | kfree(req); |
a0044bdf | 501 | } |
62f96cb0 | 502 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
503 | |
504 | list_for_each_safe(list, next_ele, &restart){ | |
505 | ubd = container_of(list, struct ubd, restart); | |
506 | list_del_init(&ubd->restart); | |
507 | spin_lock_irqsave(&ubd->lock, flags); | |
508 | do_ubd_request(ubd->queue); | |
509 | spin_unlock_irqrestore(&ubd->lock, flags); | |
510 | } | |
1da177e4 LT |
511 | } |
512 | ||
7bea96fd | 513 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 514 | { |
91acb21f | 515 | ubd_handler(); |
dc764e50 | 516 | return IRQ_HANDLED; |
91acb21f | 517 | } |
09ace81c | 518 | |
91acb21f JD |
519 | /* Only changed by ubd_init, which is an initcall. */ |
520 | static int io_pid = -1; | |
09ace81c | 521 | |
5dc62b1b | 522 | static void kill_io_thread(void) |
91acb21f | 523 | { |
6c29256c | 524 | if(io_pid != -1) |
91acb21f | 525 | os_kill_process(io_pid, 1); |
09ace81c | 526 | } |
1da177e4 | 527 | |
91acb21f JD |
528 | __uml_exitcall(kill_io_thread); |
529 | ||
d8d7c28e | 530 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
531 | { |
532 | char *file; | |
533 | ||
7d314e34 | 534 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
dc764e50 | 535 | return os_file_size(file, size_out); |
1da177e4 LT |
536 | } |
537 | ||
5dc62b1b WC |
538 | static int read_cow_bitmap(int fd, void *buf, int offset, int len) |
539 | { | |
540 | int err; | |
541 | ||
542 | err = os_seek_file(fd, offset); | |
543 | if (err < 0) | |
544 | return err; | |
545 | ||
546 | err = os_read_file(fd, buf, len); | |
547 | if (err < 0) | |
548 | return err; | |
549 | ||
550 | return 0; | |
551 | } | |
552 | ||
553 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
554 | { | |
555 | unsigned long modtime; | |
556 | unsigned long long actual; | |
557 | int err; | |
558 | ||
559 | err = os_file_modtime(file, &modtime); | |
560 | if (err < 0) { | |
561 | printk(KERN_ERR "Failed to get modification time of backing " | |
562 | "file \"%s\", err = %d\n", file, -err); | |
563 | return err; | |
564 | } | |
565 | ||
566 | err = os_file_size(file, &actual); | |
567 | if (err < 0) { | |
568 | printk(KERN_ERR "Failed to get size of backing file \"%s\", " | |
569 | "err = %d\n", file, -err); | |
570 | return err; | |
571 | } | |
572 | ||
573 | if (actual != size) { | |
574 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
575 | * the typecast.*/ | |
576 | printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " | |
577 | "vs backing file\n", (unsigned long long) size, actual); | |
578 | return -EINVAL; | |
579 | } | |
580 | if (modtime != mtime) { | |
581 | printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " | |
582 | "backing file\n", mtime, modtime); | |
583 | return -EINVAL; | |
584 | } | |
585 | return 0; | |
586 | } | |
587 | ||
588 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) | |
589 | { | |
590 | struct uml_stat buf1, buf2; | |
591 | int err; | |
592 | ||
593 | if (from_cmdline == NULL) | |
594 | return 0; | |
595 | if (!strcmp(from_cmdline, from_cow)) | |
596 | return 0; | |
597 | ||
598 | err = os_stat_file(from_cmdline, &buf1); | |
599 | if (err < 0) { | |
600 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, | |
601 | -err); | |
602 | return 0; | |
603 | } | |
604 | err = os_stat_file(from_cow, &buf2); | |
605 | if (err < 0) { | |
606 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, | |
607 | -err); | |
608 | return 1; | |
609 | } | |
610 | if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
611 | return 0; | |
612 | ||
613 | printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " | |
614 | "\"%s\" specified in COW header of \"%s\"\n", | |
615 | from_cmdline, from_cow, cow); | |
616 | return 1; | |
617 | } | |
618 | ||
619 | static int open_ubd_file(char *file, struct openflags *openflags, int shared, | |
620 | char **backing_file_out, int *bitmap_offset_out, | |
621 | unsigned long *bitmap_len_out, int *data_offset_out, | |
622 | int *create_cow_out) | |
623 | { | |
624 | time_t mtime; | |
625 | unsigned long long size; | |
626 | __u32 version, align; | |
627 | char *backing_file; | |
628 | int fd, err, sectorsize, asked_switch, mode = 0644; | |
629 | ||
630 | fd = os_open_file(file, *openflags, mode); | |
631 | if (fd < 0) { | |
632 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
633 | *create_cow_out = 1; | |
634 | if (!openflags->w || | |
635 | ((fd != -EROFS) && (fd != -EACCES))) | |
636 | return fd; | |
637 | openflags->w = 0; | |
638 | fd = os_open_file(file, *openflags, mode); | |
639 | if (fd < 0) | |
640 | return fd; | |
641 | } | |
642 | ||
643 | if (shared) | |
644 | printk(KERN_INFO "Not locking \"%s\" on the host\n", file); | |
645 | else { | |
646 | err = os_lock_file(fd, openflags->w); | |
647 | if (err < 0) { | |
648 | printk(KERN_ERR "Failed to lock '%s', err = %d\n", | |
649 | file, -err); | |
650 | goto out_close; | |
651 | } | |
652 | } | |
653 | ||
654 | /* Successful return case! */ | |
655 | if (backing_file_out == NULL) | |
656 | return fd; | |
657 | ||
658 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
659 | &size, §orsize, &align, bitmap_offset_out); | |
660 | if (err && (*backing_file_out != NULL)) { | |
661 | printk(KERN_ERR "Failed to read COW header from COW file " | |
662 | "\"%s\", errno = %d\n", file, -err); | |
663 | goto out_close; | |
664 | } | |
665 | if (err) | |
666 | return fd; | |
667 | ||
668 | asked_switch = path_requires_switch(*backing_file_out, backing_file, | |
669 | file); | |
670 | ||
671 | /* Allow switching only if no mismatch. */ | |
672 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, | |
673 | mtime)) { | |
674 | printk(KERN_ERR "Switching backing file to '%s'\n", | |
675 | *backing_file_out); | |
676 | err = write_cow_header(file, fd, *backing_file_out, | |
677 | sectorsize, align, &size); | |
678 | if (err) { | |
679 | printk(KERN_ERR "Switch failed, errno = %d\n", -err); | |
680 | goto out_close; | |
681 | } | |
682 | } else { | |
683 | *backing_file_out = backing_file; | |
684 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
685 | if (err) | |
686 | goto out_close; | |
687 | } | |
688 | ||
689 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
690 | bitmap_len_out, data_offset_out); | |
691 | ||
692 | return fd; | |
693 | out_close: | |
694 | os_close_file(fd); | |
695 | return err; | |
696 | } | |
697 | ||
698 | static int create_cow_file(char *cow_file, char *backing_file, | |
699 | struct openflags flags, | |
700 | int sectorsize, int alignment, int *bitmap_offset_out, | |
701 | unsigned long *bitmap_len_out, int *data_offset_out) | |
702 | { | |
703 | int err, fd; | |
704 | ||
705 | flags.c = 1; | |
706 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); | |
707 | if (fd < 0) { | |
708 | err = fd; | |
709 | printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", | |
710 | cow_file, -err); | |
711 | goto out; | |
712 | } | |
713 | ||
714 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
715 | bitmap_offset_out, bitmap_len_out, | |
716 | data_offset_out); | |
717 | if (!err) | |
718 | return fd; | |
719 | os_close_file(fd); | |
720 | out: | |
721 | return err; | |
722 | } | |
723 | ||
5f75a4f8 | 724 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 725 | { |
7d314e34 PBG |
726 | os_close_file(ubd_dev->fd); |
727 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
728 | return; |
729 | ||
7d314e34 PBG |
730 | os_close_file(ubd_dev->cow.fd); |
731 | vfree(ubd_dev->cow.bitmap); | |
732 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
733 | } |
734 | ||
7d314e34 | 735 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
736 | { |
737 | struct openflags flags; | |
738 | char **back_ptr; | |
739 | int err, create_cow, *create_ptr; | |
0bf16bff | 740 | int fd; |
1da177e4 | 741 | |
7d314e34 | 742 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 743 | create_cow = 0; |
7d314e34 PBG |
744 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
745 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
746 | |
747 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
748 | back_ptr, &ubd_dev->cow.bitmap_offset, |
749 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 750 | create_ptr); |
1da177e4 | 751 | |
0bf16bff PBG |
752 | if((fd == -ENOENT) && create_cow){ |
753 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
754 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
755 | &ubd_dev->cow.bitmap_offset, | |
756 | &ubd_dev->cow.bitmap_len, | |
757 | &ubd_dev->cow.data_offset); | |
0bf16bff | 758 | if(fd >= 0){ |
1da177e4 | 759 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 760 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
761 | } |
762 | } | |
763 | ||
0bf16bff | 764 | if(fd < 0){ |
7d314e34 | 765 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
766 | -fd); |
767 | return fd; | |
1da177e4 | 768 | } |
0bf16bff | 769 | ubd_dev->fd = fd; |
1da177e4 | 770 | |
7d314e34 | 771 | if(ubd_dev->cow.file != NULL){ |
f4768ffd JD |
772 | blk_queue_max_sectors(ubd_dev->queue, 8 * sizeof(long)); |
773 | ||
1da177e4 | 774 | err = -ENOMEM; |
da2486ba | 775 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 776 | if(ubd_dev->cow.bitmap == NULL){ |
1da177e4 LT |
777 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
778 | goto error; | |
779 | } | |
780 | flush_tlb_kernel_vm(); | |
781 | ||
7d314e34 PBG |
782 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
783 | ubd_dev->cow.bitmap_offset, | |
784 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
785 | if(err < 0) |
786 | goto error; | |
787 | ||
7d314e34 | 788 | flags = ubd_dev->openflags; |
1da177e4 | 789 | flags.w = 0; |
7d314e34 | 790 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 791 | NULL, NULL, NULL, NULL); |
1da177e4 | 792 | if(err < 0) goto error; |
7d314e34 | 793 | ubd_dev->cow.fd = err; |
1da177e4 | 794 | } |
dc764e50 | 795 | return 0; |
1da177e4 | 796 | error: |
7d314e34 | 797 | os_close_file(ubd_dev->fd); |
dc764e50 | 798 | return err; |
1da177e4 LT |
799 | } |
800 | ||
2e3f5251 JD |
801 | static void ubd_device_release(struct device *dev) |
802 | { | |
803 | struct ubd *ubd_dev = dev->driver_data; | |
804 | ||
805 | blk_cleanup_queue(ubd_dev->queue); | |
806 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
807 | } | |
808 | ||
5f75a4f8 | 809 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 810 | struct gendisk **disk_out) |
1da177e4 LT |
811 | { |
812 | struct gendisk *disk; | |
1da177e4 LT |
813 | |
814 | disk = alloc_disk(1 << UBD_SHIFT); | |
815 | if(disk == NULL) | |
dc764e50 | 816 | return -ENOMEM; |
1da177e4 LT |
817 | |
818 | disk->major = major; | |
819 | disk->first_minor = unit << UBD_SHIFT; | |
820 | disk->fops = &ubd_blops; | |
821 | set_capacity(disk, size / 512); | |
ce7b0f46 | 822 | if(major == MAJOR_NR) |
1da177e4 | 823 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 824 | else |
1da177e4 | 825 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
826 | |
827 | /* sysfs register (not for ide fake devices) */ | |
828 | if (major == MAJOR_NR) { | |
7d314e34 PBG |
829 | ubd_devs[unit].pdev.id = unit; |
830 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 JD |
831 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
832 | ubd_devs[unit].pdev.dev.driver_data = &ubd_devs[unit]; | |
7d314e34 PBG |
833 | platform_device_register(&ubd_devs[unit].pdev); |
834 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
835 | } |
836 | ||
7d314e34 | 837 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 838 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
839 | add_disk(disk); |
840 | ||
841 | *disk_out = disk; | |
842 | return 0; | |
843 | } | |
844 | ||
845 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
846 | ||
f28169d2 | 847 | static int ubd_add(int n, char **error_out) |
1da177e4 | 848 | { |
7d314e34 | 849 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 850 | int err = 0; |
1da177e4 | 851 | |
7d314e34 | 852 | if(ubd_dev->file == NULL) |
ec7cf783 | 853 | goto out; |
1da177e4 | 854 | |
7d314e34 | 855 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
856 | if(err < 0){ |
857 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 858 | goto out; |
f28169d2 | 859 | } |
1da177e4 | 860 | |
7d314e34 | 861 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 862 | |
a0044bdf | 863 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 864 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 865 | |
62f96cb0 JD |
866 | err = -ENOMEM; |
867 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
868 | if (ubd_dev->queue == NULL) { | |
869 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 870 | goto out; |
62f96cb0 JD |
871 | } |
872 | ubd_dev->queue->queuedata = ubd_dev; | |
873 | ||
a0044bdf | 874 | blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG); |
62f96cb0 JD |
875 | err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); |
876 | if(err){ | |
877 | *error_out = "Failed to register device"; | |
878 | goto out_cleanup; | |
879 | } | |
6c29256c | 880 | |
1da177e4 | 881 | if(fake_major != MAJOR_NR) |
5f75a4f8 | 882 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 883 | &fake_gendisk[n]); |
1da177e4 | 884 | |
83380cc1 JD |
885 | /* |
886 | * Perhaps this should also be under the "if (fake_major)" above | |
887 | * using the fake_disk->disk_name | |
888 | */ | |
1da177e4 LT |
889 | if (fake_ide) |
890 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
891 | ||
ec7cf783 | 892 | err = 0; |
ec7cf783 JD |
893 | out: |
894 | return err; | |
62f96cb0 JD |
895 | |
896 | out_cleanup: | |
897 | blk_cleanup_queue(ubd_dev->queue); | |
898 | goto out; | |
1da177e4 LT |
899 | } |
900 | ||
f28169d2 | 901 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 902 | { |
e7f6552f | 903 | int n, ret; |
1da177e4 | 904 | |
f28169d2 JD |
905 | /* This string is possibly broken up and stored, so it's only |
906 | * freed if ubd_setup_common fails, or if only general options | |
907 | * were set. | |
908 | */ | |
970d6e3a | 909 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 910 | if (str == NULL) { |
f28169d2 JD |
911 | *error_out = "Failed to allocate memory"; |
912 | return -ENOMEM; | |
1da177e4 | 913 | } |
f28169d2 JD |
914 | |
915 | ret = ubd_setup_common(str, &n, error_out); | |
916 | if (ret) | |
e7f6552f | 917 | goto err_free; |
f28169d2 | 918 | |
e7f6552f PBG |
919 | if (n == -1) { |
920 | ret = 0; | |
d8d7c28e | 921 | goto err_free; |
1da177e4 | 922 | } |
1da177e4 | 923 | |
dc764e50 | 924 | mutex_lock(&ubd_lock); |
f28169d2 | 925 | ret = ubd_add(n, error_out); |
e7f6552f | 926 | if (ret) |
7d314e34 | 927 | ubd_devs[n].file = NULL; |
dc764e50 | 928 | mutex_unlock(&ubd_lock); |
1da177e4 | 929 | |
e7f6552f | 930 | out: |
dc764e50 | 931 | return ret; |
e7f6552f PBG |
932 | |
933 | err_free: | |
934 | kfree(str); | |
935 | goto out; | |
1da177e4 LT |
936 | } |
937 | ||
938 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
939 | { | |
7d314e34 | 940 | struct ubd *ubd_dev; |
1da177e4 LT |
941 | int n, len = 0; |
942 | ||
943 | n = parse_unit(&name); | |
944 | if((n >= MAX_DEV) || (n < 0)){ | |
945 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 946 | return -1; |
1da177e4 LT |
947 | } |
948 | ||
7d314e34 | 949 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 950 | mutex_lock(&ubd_lock); |
1da177e4 | 951 | |
7d314e34 | 952 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
953 | CONFIG_CHUNK(str, size, len, "", 1); |
954 | goto out; | |
955 | } | |
956 | ||
7d314e34 | 957 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 958 | |
7d314e34 | 959 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 960 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 961 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
962 | } |
963 | else CONFIG_CHUNK(str, size, len, "", 1); | |
964 | ||
965 | out: | |
d7fb2c38 | 966 | mutex_unlock(&ubd_lock); |
dc764e50 | 967 | return len; |
1da177e4 LT |
968 | } |
969 | ||
29d56cfe JD |
970 | static int ubd_id(char **str, int *start_out, int *end_out) |
971 | { | |
dc764e50 | 972 | int n; |
29d56cfe JD |
973 | |
974 | n = parse_unit(str); | |
dc764e50 JD |
975 | *start_out = 0; |
976 | *end_out = MAX_DEV - 1; | |
977 | return n; | |
29d56cfe JD |
978 | } |
979 | ||
f28169d2 | 980 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 981 | { |
2e3f5251 | 982 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 983 | struct ubd *ubd_dev; |
29d56cfe | 984 | int err = -ENODEV; |
1da177e4 | 985 | |
d7fb2c38 | 986 | mutex_lock(&ubd_lock); |
1da177e4 | 987 | |
7d314e34 | 988 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 989 | |
7d314e34 | 990 | if(ubd_dev->file == NULL) |
29d56cfe | 991 | goto out; |
1da177e4 | 992 | |
29d56cfe JD |
993 | /* you cannot remove a open disk */ |
994 | err = -EBUSY; | |
7d314e34 | 995 | if(ubd_dev->count > 0) |
1da177e4 LT |
996 | goto out; |
997 | ||
dc764e50 | 998 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
999 | if(disk != NULL){ |
1000 | del_gendisk(disk); | |
1001 | put_disk(disk); | |
1002 | } | |
1da177e4 LT |
1003 | |
1004 | if(fake_gendisk[n] != NULL){ | |
1005 | del_gendisk(fake_gendisk[n]); | |
1006 | put_disk(fake_gendisk[n]); | |
1007 | fake_gendisk[n] = NULL; | |
1008 | } | |
1009 | ||
1da177e4 | 1010 | err = 0; |
2e3f5251 | 1011 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 1012 | out: |
d7fb2c38 | 1013 | mutex_unlock(&ubd_lock); |
29d56cfe | 1014 | return err; |
1da177e4 LT |
1015 | } |
1016 | ||
f28169d2 | 1017 | /* All these are called by mconsole in process context and without |
b8831a1d | 1018 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 1019 | */ |
1da177e4 | 1020 | static struct mc_device ubd_mc = { |
84f48d4f | 1021 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
1022 | .name = "ubd", |
1023 | .config = ubd_config, | |
dc764e50 | 1024 | .get_config = ubd_get_config, |
29d56cfe | 1025 | .id = ubd_id, |
1da177e4 LT |
1026 | .remove = ubd_remove, |
1027 | }; | |
1028 | ||
d8d7c28e | 1029 | static int __init ubd_mc_init(void) |
1da177e4 LT |
1030 | { |
1031 | mconsole_register_dev(&ubd_mc); | |
1032 | return 0; | |
1033 | } | |
1034 | ||
1035 | __initcall(ubd_mc_init); | |
1036 | ||
d8d7c28e PBG |
1037 | static int __init ubd0_init(void) |
1038 | { | |
1039 | struct ubd *ubd_dev = &ubd_devs[0]; | |
1040 | ||
b8831a1d | 1041 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
1042 | if(ubd_dev->file == NULL) |
1043 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
1044 | mutex_unlock(&ubd_lock); |
1045 | ||
dc764e50 | 1046 | return 0; |
d8d7c28e PBG |
1047 | } |
1048 | ||
1049 | __initcall(ubd0_init); | |
1050 | ||
b8831a1d | 1051 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
1052 | static struct platform_driver ubd_driver = { |
1053 | .driver = { | |
1054 | .name = DRIVER_NAME, | |
1055 | }, | |
1da177e4 LT |
1056 | }; |
1057 | ||
d8d7c28e | 1058 | static int __init ubd_init(void) |
1da177e4 | 1059 | { |
f28169d2 JD |
1060 | char *error; |
1061 | int i, err; | |
1da177e4 | 1062 | |
1da177e4 LT |
1063 | if (register_blkdev(MAJOR_NR, "ubd")) |
1064 | return -1; | |
1065 | ||
1da177e4 LT |
1066 | if (fake_major != MAJOR_NR) { |
1067 | char name[sizeof("ubd_nnn\0")]; | |
1068 | ||
1069 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
1070 | if (register_blkdev(fake_major, "ubd")) |
1071 | return -1; | |
1072 | } | |
3ae5eaec | 1073 | platform_driver_register(&ubd_driver); |
dc764e50 | 1074 | mutex_lock(&ubd_lock); |
f28169d2 JD |
1075 | for (i = 0; i < MAX_DEV; i++){ |
1076 | err = ubd_add(i, &error); | |
1077 | if(err) | |
1078 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
1079 | "%s\n", i, error); | |
1080 | } | |
dc764e50 | 1081 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
1082 | return 0; |
1083 | } | |
1084 | ||
1085 | late_initcall(ubd_init); | |
1086 | ||
d8d7c28e | 1087 | static int __init ubd_driver_init(void){ |
91acb21f JD |
1088 | unsigned long stack; |
1089 | int err; | |
1090 | ||
1091 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
1092 | if(global_openflags.s){ | |
1093 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
1094 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
1095 | * enough. So use anyway the io thread. */ | |
1096 | } | |
1097 | stack = alloc_stack(0, 0); | |
6c29256c | 1098 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
1099 | &thread_fd); |
1100 | if(io_pid < 0){ | |
6c29256c | 1101 | printk(KERN_ERR |
91acb21f JD |
1102 | "ubd : Failed to start I/O thread (errno = %d) - " |
1103 | "falling back to synchronous I/O\n", -io_pid); | |
1104 | io_pid = -1; | |
dc764e50 | 1105 | return 0; |
91acb21f | 1106 | } |
6c29256c | 1107 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 1108 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
1109 | if(err != 0) |
1110 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 1111 | return 0; |
91acb21f JD |
1112 | } |
1113 | ||
1114 | device_initcall(ubd_driver_init); | |
1115 | ||
1da177e4 LT |
1116 | static int ubd_open(struct inode *inode, struct file *filp) |
1117 | { | |
1118 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 1119 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
1120 | int err = 0; |
1121 | ||
7d314e34 PBG |
1122 | if(ubd_dev->count == 0){ |
1123 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
1124 | if(err){ |
1125 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 1126 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
1127 | goto out; |
1128 | } | |
1129 | } | |
7d314e34 PBG |
1130 | ubd_dev->count++; |
1131 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
1132 | |
1133 | /* This should no more be needed. And it didn't work anyway to exclude | |
1134 | * read-write remounting of filesystems.*/ | |
7d314e34 | 1135 | /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 1136 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 1137 | err = -EROFS; |
2c49be99 | 1138 | }*/ |
1da177e4 | 1139 | out: |
dc764e50 | 1140 | return err; |
1da177e4 LT |
1141 | } |
1142 | ||
1143 | static int ubd_release(struct inode * inode, struct file * file) | |
1144 | { | |
1145 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 1146 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 1147 | |
7d314e34 | 1148 | if(--ubd_dev->count == 0) |
5f75a4f8 | 1149 | ubd_close_dev(ubd_dev); |
dc764e50 | 1150 | return 0; |
1da177e4 LT |
1151 | } |
1152 | ||
91acb21f JD |
1153 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
1154 | __u64 *cow_offset, unsigned long *bitmap, | |
1155 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
1156 | __u64 bitmap_len) | |
1da177e4 | 1157 | { |
91acb21f JD |
1158 | __u64 sector = io_offset >> 9; |
1159 | int i, update_bitmap = 0; | |
1160 | ||
1161 | for(i = 0; i < length >> 9; i++){ | |
1162 | if(cow_mask != NULL) | |
1163 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1164 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1165 | continue; | |
1da177e4 | 1166 | |
91acb21f JD |
1167 | update_bitmap = 1; |
1168 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1169 | } | |
1170 | ||
1171 | if(!update_bitmap) | |
1172 | return; | |
1da177e4 | 1173 | |
91acb21f | 1174 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1175 | |
91acb21f JD |
1176 | /* This takes care of the case where we're exactly at the end of the |
1177 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1178 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1179 | * for the original diagnosis. | |
1180 | */ | |
6d074242 JO |
1181 | if (*cow_offset == (DIV_ROUND_UP(bitmap_len, |
1182 | sizeof(unsigned long)) - 1)) | |
91acb21f JD |
1183 | (*cow_offset)--; |
1184 | ||
1185 | bitmap_words[0] = bitmap[*cow_offset]; | |
1186 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1187 | ||
1188 | *cow_offset *= sizeof(unsigned long); | |
1189 | *cow_offset += bitmap_offset; | |
1190 | } | |
1191 | ||
1192 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1193 | __u64 bitmap_offset, __u64 bitmap_len) | |
1194 | { | |
1195 | __u64 sector = req->offset >> 9; | |
1196 | int i; | |
1197 | ||
1198 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1199 | panic("Operation too long"); | |
1200 | ||
1201 | if(req->op == UBD_READ) { | |
1202 | for(i = 0; i < req->length >> 9; i++){ | |
1203 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1204 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1205 | &req->sector_mask); |
dc764e50 | 1206 | } |
91acb21f JD |
1207 | } |
1208 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1209 | &req->cow_offset, bitmap, bitmap_offset, | |
1210 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1211 | } |
1212 | ||
62f96cb0 | 1213 | /* Called with dev->lock held */ |
a0044bdf JD |
1214 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1215 | unsigned long long offset, int page_offset, | |
1216 | int len, struct page *page) | |
1da177e4 LT |
1217 | { |
1218 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1219 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1220 | |
62f96cb0 | 1221 | io_req->req = req; |
a0044bdf JD |
1222 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1223 | ubd_dev->fd; | |
7d314e34 | 1224 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1225 | io_req->cow_offset = -1; |
1da177e4 LT |
1226 | io_req->offset = offset; |
1227 | io_req->length = len; | |
1228 | io_req->error = 0; | |
91acb21f JD |
1229 | io_req->sector_mask = 0; |
1230 | ||
1231 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1232 | io_req->offsets[0] = 0; |
7d314e34 | 1233 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1234 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1235 | io_req->sectorsize = 1 << 9; |
1236 | ||
7d314e34 | 1237 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1238 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1239 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1240 | |
1da177e4 LT |
1241 | } |
1242 | ||
62f96cb0 | 1243 | /* Called with dev->lock held */ |
165125e1 | 1244 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1245 | { |
2adcec21 | 1246 | struct io_thread_req *io_req; |
1da177e4 | 1247 | struct request *req; |
0a6d3a2a | 1248 | int n, last_sectors; |
a0044bdf JD |
1249 | |
1250 | while(1){ | |
2a9529a0 | 1251 | struct ubd *dev = q->queuedata; |
a0044bdf JD |
1252 | if(dev->end_sg == 0){ |
1253 | struct request *req = elv_next_request(q); | |
1254 | if(req == NULL) | |
1255 | return; | |
1256 | ||
1257 | dev->request = req; | |
1258 | blkdev_dequeue_request(req); | |
1259 | dev->start_sg = 0; | |
1260 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1261 | } | |
1262 | ||
1263 | req = dev->request; | |
0a6d3a2a | 1264 | last_sectors = 0; |
a0044bdf JD |
1265 | while(dev->start_sg < dev->end_sg){ |
1266 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1267 | ||
0a6d3a2a | 1268 | req->sector += last_sectors; |
2adcec21 | 1269 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1270 | GFP_ATOMIC); |
2adcec21 JD |
1271 | if(io_req == NULL){ |
1272 | if(list_empty(&dev->restart)) | |
1273 | list_add(&dev->restart, &restart); | |
1274 | return; | |
1275 | } | |
1276 | prepare_request(req, io_req, | |
a0044bdf | 1277 | (unsigned long long) req->sector << 9, |
45711f1a | 1278 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1279 | |
0a6d3a2a | 1280 | last_sectors = sg->length >> 9; |
a6ea4cce JD |
1281 | n = os_write_file(thread_fd, &io_req, |
1282 | sizeof(struct io_thread_req *)); | |
2adcec21 | 1283 | if(n != sizeof(struct io_thread_req *)){ |
a0044bdf JD |
1284 | if(n != -EAGAIN) |
1285 | printk("write to io thread failed, " | |
1286 | "errno = %d\n", -n); | |
1287 | else if(list_empty(&dev->restart)) | |
1288 | list_add(&dev->restart, &restart); | |
12429bf9 | 1289 | kfree(io_req); |
a0044bdf JD |
1290 | return; |
1291 | } | |
1292 | ||
a0044bdf | 1293 | dev->start_sg++; |
1da177e4 | 1294 | } |
a0044bdf JD |
1295 | dev->end_sg = 0; |
1296 | dev->request = NULL; | |
1da177e4 LT |
1297 | } |
1298 | } | |
1299 | ||
a885c8c4 CH |
1300 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1301 | { | |
7d314e34 | 1302 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1303 | |
1304 | geo->heads = 128; | |
1305 | geo->sectors = 32; | |
7d314e34 | 1306 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1307 | return 0; |
1308 | } | |
1309 | ||
1da177e4 LT |
1310 | static int ubd_ioctl(struct inode * inode, struct file * file, |
1311 | unsigned int cmd, unsigned long arg) | |
1312 | { | |
7d314e34 | 1313 | struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; |
1da177e4 LT |
1314 | struct hd_driveid ubd_id = { |
1315 | .cyls = 0, | |
1316 | .heads = 128, | |
1317 | .sectors = 32, | |
1318 | }; | |
1319 | ||
1320 | switch (cmd) { | |
1da177e4 | 1321 | struct cdrom_volctrl volume; |
1da177e4 | 1322 | case HDIO_GET_IDENTITY: |
7d314e34 | 1323 | ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); |
1da177e4 LT |
1324 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1325 | sizeof(ubd_id))) | |
dc764e50 JD |
1326 | return -EFAULT; |
1327 | return 0; | |
b8831a1d | 1328 | |
1da177e4 LT |
1329 | case CDROMVOLREAD: |
1330 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1331 | return -EFAULT; |
1da177e4 LT |
1332 | volume.channel0 = 255; |
1333 | volume.channel1 = 255; | |
1334 | volume.channel2 = 255; | |
1335 | volume.channel3 = 255; | |
1336 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1337 | return -EFAULT; |
1338 | return 0; | |
1da177e4 | 1339 | } |
dc764e50 | 1340 | return -EINVAL; |
1da177e4 LT |
1341 | } |
1342 | ||
91acb21f | 1343 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1344 | { |
91acb21f | 1345 | int n; |
1da177e4 | 1346 | |
91acb21f | 1347 | if(req->cow_offset == -1) |
dc764e50 | 1348 | return 0; |
1da177e4 | 1349 | |
91acb21f JD |
1350 | n = os_seek_file(req->fds[1], req->cow_offset); |
1351 | if(n < 0){ | |
1352 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
dc764e50 | 1353 | return 1; |
91acb21f | 1354 | } |
1da177e4 | 1355 | |
a6ea4cce JD |
1356 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1357 | sizeof(req->bitmap_words)); | |
91acb21f JD |
1358 | if(n != sizeof(req->bitmap_words)){ |
1359 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1360 | req->fds[1]); | |
dc764e50 | 1361 | return 1; |
91acb21f | 1362 | } |
1da177e4 | 1363 | |
dc764e50 | 1364 | return 0; |
91acb21f | 1365 | } |
1da177e4 | 1366 | |
5dc62b1b | 1367 | static void do_io(struct io_thread_req *req) |
91acb21f JD |
1368 | { |
1369 | char *buf; | |
1370 | unsigned long len; | |
1371 | int n, nsectors, start, end, bit; | |
1372 | int err; | |
1373 | __u64 off; | |
1374 | ||
1375 | nsectors = req->length / req->sectorsize; | |
1376 | start = 0; | |
1377 | do { | |
1378 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1379 | end = start; | |
1380 | while((end < nsectors) && | |
1381 | (ubd_test_bit(end, (unsigned char *) | |
1382 | &req->sector_mask) == bit)) | |
1383 | end++; | |
1384 | ||
1385 | off = req->offset + req->offsets[bit] + | |
1386 | start * req->sectorsize; | |
1387 | len = (end - start) * req->sectorsize; | |
1388 | buf = &req->buffer[start * req->sectorsize]; | |
1389 | ||
1390 | err = os_seek_file(req->fds[bit], off); | |
1391 | if(err < 0){ | |
1392 | printk("do_io - lseek failed : err = %d\n", -err); | |
1393 | req->error = 1; | |
1394 | return; | |
1395 | } | |
1396 | if(req->op == UBD_READ){ | |
1397 | n = 0; | |
1398 | do { | |
1399 | buf = &buf[n]; | |
1400 | len -= n; | |
a6ea4cce | 1401 | n = os_read_file(req->fds[bit], buf, len); |
91acb21f JD |
1402 | if (n < 0) { |
1403 | printk("do_io - read failed, err = %d " | |
1404 | "fd = %d\n", -n, req->fds[bit]); | |
1405 | req->error = 1; | |
1406 | return; | |
1407 | } | |
1408 | } while((n < len) && (n != 0)); | |
1409 | if (n < len) memset(&buf[n], 0, len - n); | |
1410 | } else { | |
a6ea4cce | 1411 | n = os_write_file(req->fds[bit], buf, len); |
91acb21f JD |
1412 | if(n != len){ |
1413 | printk("do_io - write failed err = %d " | |
1414 | "fd = %d\n", -n, req->fds[bit]); | |
1415 | req->error = 1; | |
1416 | return; | |
1417 | } | |
1418 | } | |
1419 | ||
1420 | start = end; | |
1421 | } while(start < nsectors); | |
1da177e4 | 1422 | |
91acb21f | 1423 | req->error = update_bitmap(req); |
1da177e4 | 1424 | } |
91acb21f JD |
1425 | |
1426 | /* Changed in start_io_thread, which is serialized by being called only | |
1427 | * from ubd_init, which is an initcall. | |
1428 | */ | |
1429 | int kernel_fd = -1; | |
1430 | ||
d8d7c28e PBG |
1431 | /* Only changed by the io thread. XXX: currently unused. */ |
1432 | static int io_count = 0; | |
91acb21f JD |
1433 | |
1434 | int io_thread(void *arg) | |
1435 | { | |
2adcec21 | 1436 | struct io_thread_req *req; |
91acb21f JD |
1437 | int n; |
1438 | ||
1439 | ignore_sigwinch_sig(); | |
1440 | while(1){ | |
a6ea4cce | 1441 | n = os_read_file(kernel_fd, &req, |
2adcec21 JD |
1442 | sizeof(struct io_thread_req *)); |
1443 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1444 | if(n < 0) |
1445 | printk("io_thread - read failed, fd = %d, " | |
1446 | "err = %d\n", kernel_fd, -n); | |
1447 | else { | |
1448 | printk("io_thread - short read, fd = %d, " | |
1449 | "length = %d\n", kernel_fd, n); | |
1450 | } | |
1451 | continue; | |
1452 | } | |
1453 | io_count++; | |
2adcec21 | 1454 | do_io(req); |
a6ea4cce | 1455 | n = os_write_file(kernel_fd, &req, |
2adcec21 JD |
1456 | sizeof(struct io_thread_req *)); |
1457 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1458 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1459 | kernel_fd, -n); | |
1460 | } | |
91acb21f | 1461 | |
1b57e9c2 JD |
1462 | return 0; |
1463 | } |