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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" | |
1da177e4 LT |
42 | #include "mem_user.h" |
43 | #include "kern_util.h" | |
44 | #include "kern.h" | |
45 | #include "mconsole_kern.h" | |
46 | #include "init.h" | |
47 | #include "irq_user.h" | |
48 | #include "irq_kern.h" | |
49 | #include "ubd_user.h" | |
1da177e4 LT |
50 | #include "os.h" |
51 | #include "mem.h" | |
52 | #include "mem_kern.h" | |
53 | #include "cow.h" | |
54 | ||
7b9014c1 | 55 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
56 | |
57 | struct io_thread_req { | |
62f96cb0 | 58 | struct request *req; |
91acb21f | 59 | enum ubd_req op; |
1da177e4 LT |
60 | int fds[2]; |
61 | unsigned long offsets[2]; | |
62 | unsigned long long offset; | |
63 | unsigned long length; | |
64 | char *buffer; | |
65 | int sectorsize; | |
91acb21f JD |
66 | unsigned long sector_mask; |
67 | unsigned long long cow_offset; | |
68 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
69 | int error; |
70 | }; | |
71 | ||
6c29256c | 72 | extern int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
73 | char **backing_file_out, int *bitmap_offset_out, |
74 | unsigned long *bitmap_len_out, int *data_offset_out, | |
75 | int *create_cow_out); | |
76 | extern int create_cow_file(char *cow_file, char *backing_file, | |
77 | struct openflags flags, int sectorsize, | |
78 | int alignment, int *bitmap_offset_out, | |
79 | unsigned long *bitmap_len_out, | |
80 | int *data_offset_out); | |
81 | extern int read_cow_bitmap(int fd, void *buf, int offset, int len); | |
91acb21f | 82 | extern void do_io(struct io_thread_req *req); |
1da177e4 | 83 | |
91acb21f | 84 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
85 | { |
86 | __u64 n; | |
87 | int bits, off; | |
88 | ||
91acb21f | 89 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
90 | n = bit / bits; |
91 | off = bit % bits; | |
91acb21f | 92 | return((data[n] & (1 << off)) != 0); |
1da177e4 LT |
93 | } |
94 | ||
91acb21f | 95 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
96 | { |
97 | __u64 n; | |
98 | int bits, off; | |
99 | ||
91acb21f | 100 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
101 | n = bit / bits; |
102 | off = bit % bits; | |
91acb21f | 103 | data[n] |= (1 << off); |
1da177e4 LT |
104 | } |
105 | /*End stuff from ubd_user.h*/ | |
106 | ||
107 | #define DRIVER_NAME "uml-blkdev" | |
108 | ||
d7fb2c38 | 109 | static DEFINE_MUTEX(ubd_lock); |
1da177e4 | 110 | |
1da177e4 LT |
111 | static int ubd_open(struct inode * inode, struct file * filp); |
112 | static int ubd_release(struct inode * inode, struct file * file); | |
113 | static int ubd_ioctl(struct inode * inode, struct file * file, | |
114 | unsigned int cmd, unsigned long arg); | |
a885c8c4 | 115 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 116 | |
97d88ac8 | 117 | #define MAX_DEV (16) |
1da177e4 | 118 | |
1da177e4 LT |
119 | static struct block_device_operations ubd_blops = { |
120 | .owner = THIS_MODULE, | |
121 | .open = ubd_open, | |
122 | .release = ubd_release, | |
123 | .ioctl = ubd_ioctl, | |
a885c8c4 | 124 | .getgeo = ubd_getgeo, |
1da177e4 LT |
125 | }; |
126 | ||
1da177e4 LT |
127 | /* Protected by ubd_lock */ |
128 | static int fake_major = MAJOR_NR; | |
1da177e4 LT |
129 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
130 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 131 | |
1da177e4 LT |
132 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
133 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
134 | .cl = 1 }) | |
135 | #else | |
136 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
137 | .cl = 1 }) | |
138 | #endif | |
1da177e4 LT |
139 | static struct openflags global_openflags = OPEN_FLAGS; |
140 | ||
141 | struct cow { | |
2a9d32f6 | 142 | /* backing file name */ |
1da177e4 | 143 | char *file; |
2a9d32f6 | 144 | /* backing file fd */ |
1da177e4 LT |
145 | int fd; |
146 | unsigned long *bitmap; | |
147 | unsigned long bitmap_len; | |
148 | int bitmap_offset; | |
149 | int data_offset; | |
150 | }; | |
151 | ||
a0044bdf JD |
152 | #define MAX_SG 64 |
153 | ||
1da177e4 | 154 | struct ubd { |
a0044bdf | 155 | struct list_head restart; |
2a9d32f6 PBG |
156 | /* name (and fd, below) of the file opened for writing, either the |
157 | * backing or the cow file. */ | |
1da177e4 LT |
158 | char *file; |
159 | int count; | |
160 | int fd; | |
161 | __u64 size; | |
162 | struct openflags boot_openflags; | |
163 | struct openflags openflags; | |
84e945e3 PBG |
164 | unsigned shared:1; |
165 | unsigned no_cow:1; | |
1da177e4 LT |
166 | struct cow cow; |
167 | struct platform_device pdev; | |
62f96cb0 JD |
168 | struct request_queue *queue; |
169 | spinlock_t lock; | |
a0044bdf JD |
170 | struct scatterlist sg[MAX_SG]; |
171 | struct request *request; | |
172 | int start_sg, end_sg; | |
1da177e4 LT |
173 | }; |
174 | ||
175 | #define DEFAULT_COW { \ | |
176 | .file = NULL, \ | |
177 | .fd = -1, \ | |
178 | .bitmap = NULL, \ | |
179 | .bitmap_offset = 0, \ | |
180 | .data_offset = 0, \ | |
181 | } | |
182 | ||
183 | #define DEFAULT_UBD { \ | |
184 | .file = NULL, \ | |
185 | .count = 0, \ | |
186 | .fd = -1, \ | |
187 | .size = -1, \ | |
188 | .boot_openflags = OPEN_FLAGS, \ | |
189 | .openflags = OPEN_FLAGS, \ | |
190 | .no_cow = 0, \ | |
6c29256c | 191 | .shared = 0, \ |
1da177e4 | 192 | .cow = DEFAULT_COW, \ |
62f96cb0 | 193 | .lock = SPIN_LOCK_UNLOCKED, \ |
a0044bdf JD |
194 | .request = NULL, \ |
195 | .start_sg = 0, \ | |
196 | .end_sg = 0, \ | |
1da177e4 LT |
197 | } |
198 | ||
b8831a1d | 199 | /* Protected by ubd_lock */ |
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; | |
1da177e4 LT |
242 | ent->data = NULL; |
243 | ent->read_proc = proc_ide_read_media; | |
244 | ent->write_proc = NULL; | |
245 | sprintf(name,"ide0/%s", dev_name); | |
246 | proc_symlink(dev_name, proc_ide_root, name); | |
247 | } | |
248 | ||
249 | static int fake_ide_setup(char *str) | |
250 | { | |
251 | fake_ide = 1; | |
252 | return(1); | |
253 | } | |
254 | ||
255 | __setup("fake_ide", fake_ide_setup); | |
256 | ||
257 | __uml_help(fake_ide_setup, | |
258 | "fake_ide\n" | |
259 | " Create ide0 entries that map onto ubd devices.\n\n" | |
260 | ); | |
261 | ||
262 | static int parse_unit(char **ptr) | |
263 | { | |
264 | char *str = *ptr, *end; | |
265 | int n = -1; | |
266 | ||
267 | if(isdigit(*str)) { | |
268 | n = simple_strtoul(str, &end, 0); | |
269 | if(end == str) | |
270 | return(-1); | |
271 | *ptr = end; | |
272 | } | |
97d88ac8 | 273 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
274 | n = *str - 'a'; |
275 | str++; | |
276 | *ptr = str; | |
277 | } | |
278 | return(n); | |
279 | } | |
280 | ||
d8d7c28e PBG |
281 | /* If *index_out == -1 at exit, the passed option was a general one; |
282 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
283 | * should not be freed on exit. | |
284 | */ | |
f28169d2 | 285 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 286 | { |
7d314e34 | 287 | struct ubd *ubd_dev; |
1da177e4 LT |
288 | struct openflags flags = global_openflags; |
289 | char *backing_file; | |
b8831a1d | 290 | int n, err = 0, i; |
1da177e4 LT |
291 | |
292 | if(index_out) *index_out = -1; | |
293 | n = *str; | |
294 | if(n == '='){ | |
295 | char *end; | |
296 | int major; | |
297 | ||
298 | str++; | |
1da177e4 LT |
299 | if(!strcmp(str, "sync")){ |
300 | global_openflags = of_sync(global_openflags); | |
b8831a1d | 301 | goto out1; |
1da177e4 | 302 | } |
b8831a1d JD |
303 | |
304 | err = -EINVAL; | |
1da177e4 LT |
305 | major = simple_strtoul(str, &end, 0); |
306 | if((*end != '\0') || (end == str)){ | |
f28169d2 | 307 | *error_out = "Didn't parse major number"; |
b8831a1d | 308 | goto out1; |
1da177e4 LT |
309 | } |
310 | ||
f28169d2 JD |
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 | 475 | |
a0044bdf | 476 | static void ubd_end_request(struct request *req, int bytes, int uptodate) |
1da177e4 | 477 | { |
a0044bdf JD |
478 | if (!end_that_request_first(req, uptodate, bytes >> 9)) { |
479 | struct ubd *dev = req->rq_disk->private_data; | |
480 | unsigned long flags; | |
481 | ||
482 | add_disk_randomness(req->rq_disk); | |
483 | spin_lock_irqsave(&dev->lock, flags); | |
484 | end_that_request_last(req, uptodate); | |
485 | spin_unlock_irqrestore(&dev->lock, flags); | |
1da177e4 | 486 | } |
1da177e4 LT |
487 | } |
488 | ||
33f775ee PBG |
489 | /* Callable only from interrupt context - otherwise you need to do |
490 | * spin_lock_irq()/spin_lock_irqsave() */ | |
a0044bdf | 491 | static inline void ubd_finish(struct request *req, int bytes) |
1da177e4 | 492 | { |
a0044bdf JD |
493 | if(bytes < 0){ |
494 | ubd_end_request(req, 0, 0); | |
495 | return; | |
496 | } | |
497 | ubd_end_request(req, bytes, 1); | |
1da177e4 LT |
498 | } |
499 | ||
a0044bdf JD |
500 | static LIST_HEAD(restart); |
501 | ||
2fe30a34 | 502 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 503 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 504 | static void ubd_handler(void) |
1da177e4 | 505 | { |
2adcec21 | 506 | struct io_thread_req *req; |
62f96cb0 | 507 | struct request *rq; |
a0044bdf JD |
508 | struct ubd *ubd; |
509 | struct list_head *list, *next_ele; | |
510 | unsigned long flags; | |
91acb21f JD |
511 | int n; |
512 | ||
a0044bdf | 513 | while(1){ |
2adcec21 JD |
514 | n = os_read_file_k(thread_fd, &req, |
515 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
516 | if(n != sizeof(req)){ |
517 | if(n == -EAGAIN) | |
518 | break; | |
519 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
520 | "err = %d\n", -n); | |
521 | return; | |
522 | } | |
62f96cb0 | 523 | |
2adcec21 JD |
524 | rq = req->req; |
525 | rq->nr_sectors -= req->length >> 9; | |
a0044bdf JD |
526 | if(rq->nr_sectors == 0) |
527 | ubd_finish(rq, rq->hard_nr_sectors << 9); | |
2adcec21 | 528 | kfree(req); |
a0044bdf | 529 | } |
62f96cb0 | 530 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
531 | |
532 | list_for_each_safe(list, next_ele, &restart){ | |
533 | ubd = container_of(list, struct ubd, restart); | |
534 | list_del_init(&ubd->restart); | |
535 | spin_lock_irqsave(&ubd->lock, flags); | |
536 | do_ubd_request(ubd->queue); | |
537 | spin_unlock_irqrestore(&ubd->lock, flags); | |
538 | } | |
1da177e4 LT |
539 | } |
540 | ||
7bea96fd | 541 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 542 | { |
91acb21f JD |
543 | ubd_handler(); |
544 | return(IRQ_HANDLED); | |
545 | } | |
09ace81c | 546 | |
91acb21f JD |
547 | /* Only changed by ubd_init, which is an initcall. */ |
548 | static int io_pid = -1; | |
09ace81c | 549 | |
91acb21f JD |
550 | void kill_io_thread(void) |
551 | { | |
6c29256c | 552 | if(io_pid != -1) |
91acb21f | 553 | os_kill_process(io_pid, 1); |
09ace81c | 554 | } |
1da177e4 | 555 | |
91acb21f JD |
556 | __uml_exitcall(kill_io_thread); |
557 | ||
d8d7c28e | 558 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
559 | { |
560 | char *file; | |
561 | ||
7d314e34 | 562 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
1da177e4 LT |
563 | return(os_file_size(file, size_out)); |
564 | } | |
565 | ||
5f75a4f8 | 566 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 567 | { |
7d314e34 PBG |
568 | os_close_file(ubd_dev->fd); |
569 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
570 | return; |
571 | ||
7d314e34 PBG |
572 | os_close_file(ubd_dev->cow.fd); |
573 | vfree(ubd_dev->cow.bitmap); | |
574 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
575 | } |
576 | ||
7d314e34 | 577 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
578 | { |
579 | struct openflags flags; | |
580 | char **back_ptr; | |
581 | int err, create_cow, *create_ptr; | |
0bf16bff | 582 | int fd; |
1da177e4 | 583 | |
7d314e34 | 584 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 585 | create_cow = 0; |
7d314e34 PBG |
586 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
587 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
588 | |
589 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
590 | back_ptr, &ubd_dev->cow.bitmap_offset, |
591 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 592 | create_ptr); |
1da177e4 | 593 | |
0bf16bff PBG |
594 | if((fd == -ENOENT) && create_cow){ |
595 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
596 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
597 | &ubd_dev->cow.bitmap_offset, | |
598 | &ubd_dev->cow.bitmap_len, | |
599 | &ubd_dev->cow.data_offset); | |
0bf16bff | 600 | if(fd >= 0){ |
1da177e4 | 601 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 602 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
603 | } |
604 | } | |
605 | ||
0bf16bff | 606 | if(fd < 0){ |
7d314e34 | 607 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
608 | -fd); |
609 | return fd; | |
1da177e4 | 610 | } |
0bf16bff | 611 | ubd_dev->fd = fd; |
1da177e4 | 612 | |
7d314e34 | 613 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 614 | err = -ENOMEM; |
7d314e34 PBG |
615 | ubd_dev->cow.bitmap = (void *) vmalloc(ubd_dev->cow.bitmap_len); |
616 | if(ubd_dev->cow.bitmap == NULL){ | |
1da177e4 LT |
617 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
618 | goto error; | |
619 | } | |
620 | flush_tlb_kernel_vm(); | |
621 | ||
7d314e34 PBG |
622 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
623 | ubd_dev->cow.bitmap_offset, | |
624 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
625 | if(err < 0) |
626 | goto error; | |
627 | ||
7d314e34 | 628 | flags = ubd_dev->openflags; |
1da177e4 | 629 | flags.w = 0; |
7d314e34 | 630 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 631 | NULL, NULL, NULL, NULL); |
1da177e4 | 632 | if(err < 0) goto error; |
7d314e34 | 633 | ubd_dev->cow.fd = err; |
1da177e4 LT |
634 | } |
635 | return(0); | |
636 | error: | |
7d314e34 | 637 | os_close_file(ubd_dev->fd); |
1da177e4 LT |
638 | return(err); |
639 | } | |
640 | ||
2e3f5251 JD |
641 | static void ubd_device_release(struct device *dev) |
642 | { | |
643 | struct ubd *ubd_dev = dev->driver_data; | |
644 | ||
645 | blk_cleanup_queue(ubd_dev->queue); | |
646 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
647 | } | |
648 | ||
5f75a4f8 | 649 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 650 | struct gendisk **disk_out) |
1da177e4 LT |
651 | { |
652 | struct gendisk *disk; | |
1da177e4 LT |
653 | |
654 | disk = alloc_disk(1 << UBD_SHIFT); | |
655 | if(disk == NULL) | |
656 | return(-ENOMEM); | |
657 | ||
658 | disk->major = major; | |
659 | disk->first_minor = unit << UBD_SHIFT; | |
660 | disk->fops = &ubd_blops; | |
661 | set_capacity(disk, size / 512); | |
ce7b0f46 | 662 | if(major == MAJOR_NR) |
1da177e4 | 663 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 664 | else |
1da177e4 | 665 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
666 | |
667 | /* sysfs register (not for ide fake devices) */ | |
668 | if (major == MAJOR_NR) { | |
7d314e34 PBG |
669 | ubd_devs[unit].pdev.id = unit; |
670 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 JD |
671 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
672 | ubd_devs[unit].pdev.dev.driver_data = &ubd_devs[unit]; | |
7d314e34 PBG |
673 | platform_device_register(&ubd_devs[unit].pdev); |
674 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
675 | } |
676 | ||
7d314e34 | 677 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 678 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
679 | add_disk(disk); |
680 | ||
681 | *disk_out = disk; | |
682 | return 0; | |
683 | } | |
684 | ||
685 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
686 | ||
f28169d2 | 687 | static int ubd_add(int n, char **error_out) |
1da177e4 | 688 | { |
7d314e34 | 689 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 690 | int err = 0; |
1da177e4 | 691 | |
7d314e34 | 692 | if(ubd_dev->file == NULL) |
ec7cf783 | 693 | goto out; |
1da177e4 | 694 | |
7d314e34 | 695 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
696 | if(err < 0){ |
697 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 698 | goto out; |
f28169d2 | 699 | } |
1da177e4 | 700 | |
7d314e34 | 701 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 702 | |
a0044bdf JD |
703 | INIT_LIST_HEAD(&ubd_dev->restart); |
704 | ||
62f96cb0 JD |
705 | err = -ENOMEM; |
706 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
707 | if (ubd_dev->queue == NULL) { | |
708 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 709 | goto out; |
62f96cb0 JD |
710 | } |
711 | ubd_dev->queue->queuedata = ubd_dev; | |
712 | ||
a0044bdf | 713 | blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG); |
62f96cb0 JD |
714 | err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); |
715 | if(err){ | |
716 | *error_out = "Failed to register device"; | |
717 | goto out_cleanup; | |
718 | } | |
6c29256c | 719 | |
1da177e4 | 720 | if(fake_major != MAJOR_NR) |
5f75a4f8 | 721 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 722 | &fake_gendisk[n]); |
1da177e4 LT |
723 | |
724 | /* perhaps this should also be under the "if (fake_major)" above */ | |
725 | /* using the fake_disk->disk_name and also the fakehd_set name */ | |
726 | if (fake_ide) | |
727 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
728 | ||
ec7cf783 | 729 | err = 0; |
ec7cf783 JD |
730 | out: |
731 | return err; | |
62f96cb0 JD |
732 | |
733 | out_cleanup: | |
734 | blk_cleanup_queue(ubd_dev->queue); | |
735 | goto out; | |
1da177e4 LT |
736 | } |
737 | ||
f28169d2 | 738 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 739 | { |
e7f6552f | 740 | int n, ret; |
1da177e4 | 741 | |
f28169d2 JD |
742 | /* This string is possibly broken up and stored, so it's only |
743 | * freed if ubd_setup_common fails, or if only general options | |
744 | * were set. | |
745 | */ | |
970d6e3a | 746 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 747 | if (str == NULL) { |
f28169d2 JD |
748 | *error_out = "Failed to allocate memory"; |
749 | return -ENOMEM; | |
1da177e4 | 750 | } |
f28169d2 JD |
751 | |
752 | ret = ubd_setup_common(str, &n, error_out); | |
753 | if (ret) | |
e7f6552f | 754 | goto err_free; |
f28169d2 | 755 | |
e7f6552f PBG |
756 | if (n == -1) { |
757 | ret = 0; | |
d8d7c28e | 758 | goto err_free; |
1da177e4 | 759 | } |
1da177e4 | 760 | |
d7fb2c38 | 761 | mutex_lock(&ubd_lock); |
f28169d2 | 762 | ret = ubd_add(n, error_out); |
e7f6552f | 763 | if (ret) |
7d314e34 | 764 | ubd_devs[n].file = NULL; |
d7fb2c38 | 765 | mutex_unlock(&ubd_lock); |
1da177e4 | 766 | |
e7f6552f PBG |
767 | out: |
768 | return ret; | |
769 | ||
770 | err_free: | |
771 | kfree(str); | |
772 | goto out; | |
1da177e4 LT |
773 | } |
774 | ||
775 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
776 | { | |
7d314e34 | 777 | struct ubd *ubd_dev; |
1da177e4 LT |
778 | int n, len = 0; |
779 | ||
780 | n = parse_unit(&name); | |
781 | if((n >= MAX_DEV) || (n < 0)){ | |
782 | *error_out = "ubd_get_config : device number out of range"; | |
783 | return(-1); | |
784 | } | |
785 | ||
7d314e34 | 786 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 787 | mutex_lock(&ubd_lock); |
1da177e4 | 788 | |
7d314e34 | 789 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
790 | CONFIG_CHUNK(str, size, len, "", 1); |
791 | goto out; | |
792 | } | |
793 | ||
7d314e34 | 794 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 795 | |
7d314e34 | 796 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 797 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 798 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
799 | } |
800 | else CONFIG_CHUNK(str, size, len, "", 1); | |
801 | ||
802 | out: | |
d7fb2c38 | 803 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
804 | return(len); |
805 | } | |
806 | ||
29d56cfe JD |
807 | static int ubd_id(char **str, int *start_out, int *end_out) |
808 | { | |
809 | int n; | |
810 | ||
811 | n = parse_unit(str); | |
812 | *start_out = 0; | |
813 | *end_out = MAX_DEV - 1; | |
814 | return n; | |
815 | } | |
816 | ||
f28169d2 | 817 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 818 | { |
2e3f5251 | 819 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 820 | struct ubd *ubd_dev; |
29d56cfe | 821 | int err = -ENODEV; |
1da177e4 | 822 | |
d7fb2c38 | 823 | mutex_lock(&ubd_lock); |
1da177e4 | 824 | |
7d314e34 | 825 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 826 | |
7d314e34 | 827 | if(ubd_dev->file == NULL) |
29d56cfe | 828 | goto out; |
1da177e4 | 829 | |
29d56cfe JD |
830 | /* you cannot remove a open disk */ |
831 | err = -EBUSY; | |
7d314e34 | 832 | if(ubd_dev->count > 0) |
1da177e4 LT |
833 | goto out; |
834 | ||
b47d2deb JD |
835 | ubd_gendisk[n] = NULL; |
836 | if(disk != NULL){ | |
837 | del_gendisk(disk); | |
838 | put_disk(disk); | |
839 | } | |
1da177e4 LT |
840 | |
841 | if(fake_gendisk[n] != NULL){ | |
842 | del_gendisk(fake_gendisk[n]); | |
843 | put_disk(fake_gendisk[n]); | |
844 | fake_gendisk[n] = NULL; | |
845 | } | |
846 | ||
1da177e4 | 847 | err = 0; |
2e3f5251 | 848 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 849 | out: |
d7fb2c38 | 850 | mutex_unlock(&ubd_lock); |
29d56cfe | 851 | return err; |
1da177e4 LT |
852 | } |
853 | ||
f28169d2 | 854 | /* All these are called by mconsole in process context and without |
b8831a1d | 855 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 856 | */ |
1da177e4 | 857 | static struct mc_device ubd_mc = { |
84f48d4f | 858 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
859 | .name = "ubd", |
860 | .config = ubd_config, | |
861 | .get_config = ubd_get_config, | |
29d56cfe | 862 | .id = ubd_id, |
1da177e4 LT |
863 | .remove = ubd_remove, |
864 | }; | |
865 | ||
d8d7c28e | 866 | static int __init ubd_mc_init(void) |
1da177e4 LT |
867 | { |
868 | mconsole_register_dev(&ubd_mc); | |
869 | return 0; | |
870 | } | |
871 | ||
872 | __initcall(ubd_mc_init); | |
873 | ||
d8d7c28e PBG |
874 | static int __init ubd0_init(void) |
875 | { | |
876 | struct ubd *ubd_dev = &ubd_devs[0]; | |
877 | ||
b8831a1d | 878 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
879 | if(ubd_dev->file == NULL) |
880 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
881 | mutex_unlock(&ubd_lock); |
882 | ||
d8d7c28e PBG |
883 | return(0); |
884 | } | |
885 | ||
886 | __initcall(ubd0_init); | |
887 | ||
b8831a1d | 888 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
889 | static struct platform_driver ubd_driver = { |
890 | .driver = { | |
891 | .name = DRIVER_NAME, | |
892 | }, | |
1da177e4 LT |
893 | }; |
894 | ||
d8d7c28e | 895 | static int __init ubd_init(void) |
1da177e4 | 896 | { |
f28169d2 JD |
897 | char *error; |
898 | int i, err; | |
1da177e4 | 899 | |
1da177e4 LT |
900 | if (register_blkdev(MAJOR_NR, "ubd")) |
901 | return -1; | |
902 | ||
1da177e4 LT |
903 | if (fake_major != MAJOR_NR) { |
904 | char name[sizeof("ubd_nnn\0")]; | |
905 | ||
906 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
907 | if (register_blkdev(fake_major, "ubd")) |
908 | return -1; | |
909 | } | |
3ae5eaec | 910 | platform_driver_register(&ubd_driver); |
b8831a1d | 911 | mutex_lock(&ubd_lock); |
f28169d2 JD |
912 | for (i = 0; i < MAX_DEV; i++){ |
913 | err = ubd_add(i, &error); | |
914 | if(err) | |
915 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
916 | "%s\n", i, error); | |
917 | } | |
b8831a1d | 918 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
919 | return 0; |
920 | } | |
921 | ||
922 | late_initcall(ubd_init); | |
923 | ||
d8d7c28e | 924 | static int __init ubd_driver_init(void){ |
91acb21f JD |
925 | unsigned long stack; |
926 | int err; | |
927 | ||
928 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
929 | if(global_openflags.s){ | |
930 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
931 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
932 | * enough. So use anyway the io thread. */ | |
933 | } | |
934 | stack = alloc_stack(0, 0); | |
6c29256c | 935 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
936 | &thread_fd); |
937 | if(io_pid < 0){ | |
6c29256c | 938 | printk(KERN_ERR |
91acb21f JD |
939 | "ubd : Failed to start I/O thread (errno = %d) - " |
940 | "falling back to synchronous I/O\n", -io_pid); | |
941 | io_pid = -1; | |
942 | return(0); | |
943 | } | |
6c29256c | 944 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 945 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
946 | if(err != 0) |
947 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 948 | return 0; |
91acb21f JD |
949 | } |
950 | ||
951 | device_initcall(ubd_driver_init); | |
952 | ||
1da177e4 LT |
953 | static int ubd_open(struct inode *inode, struct file *filp) |
954 | { | |
955 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 956 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
957 | int err = 0; |
958 | ||
7d314e34 PBG |
959 | if(ubd_dev->count == 0){ |
960 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
961 | if(err){ |
962 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 963 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
964 | goto out; |
965 | } | |
966 | } | |
7d314e34 PBG |
967 | ubd_dev->count++; |
968 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
969 | |
970 | /* This should no more be needed. And it didn't work anyway to exclude | |
971 | * read-write remounting of filesystems.*/ | |
7d314e34 | 972 | /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 973 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 974 | err = -EROFS; |
2c49be99 | 975 | }*/ |
1da177e4 LT |
976 | out: |
977 | return(err); | |
978 | } | |
979 | ||
980 | static int ubd_release(struct inode * inode, struct file * file) | |
981 | { | |
982 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 983 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 984 | |
7d314e34 | 985 | if(--ubd_dev->count == 0) |
5f75a4f8 | 986 | ubd_close_dev(ubd_dev); |
1da177e4 LT |
987 | return(0); |
988 | } | |
989 | ||
91acb21f JD |
990 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
991 | __u64 *cow_offset, unsigned long *bitmap, | |
992 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
993 | __u64 bitmap_len) | |
1da177e4 | 994 | { |
91acb21f JD |
995 | __u64 sector = io_offset >> 9; |
996 | int i, update_bitmap = 0; | |
997 | ||
998 | for(i = 0; i < length >> 9; i++){ | |
999 | if(cow_mask != NULL) | |
1000 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1001 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1002 | continue; | |
1da177e4 | 1003 | |
91acb21f JD |
1004 | update_bitmap = 1; |
1005 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1006 | } | |
1007 | ||
1008 | if(!update_bitmap) | |
1009 | return; | |
1da177e4 | 1010 | |
91acb21f | 1011 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1012 | |
91acb21f JD |
1013 | /* This takes care of the case where we're exactly at the end of the |
1014 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1015 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1016 | * for the original diagnosis. | |
1017 | */ | |
1018 | if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / | |
1019 | sizeof(unsigned long) - 1)) | |
1020 | (*cow_offset)--; | |
1021 | ||
1022 | bitmap_words[0] = bitmap[*cow_offset]; | |
1023 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1024 | ||
1025 | *cow_offset *= sizeof(unsigned long); | |
1026 | *cow_offset += bitmap_offset; | |
1027 | } | |
1028 | ||
1029 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1030 | __u64 bitmap_offset, __u64 bitmap_len) | |
1031 | { | |
1032 | __u64 sector = req->offset >> 9; | |
1033 | int i; | |
1034 | ||
1035 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1036 | panic("Operation too long"); | |
1037 | ||
1038 | if(req->op == UBD_READ) { | |
1039 | for(i = 0; i < req->length >> 9; i++){ | |
1040 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1041 | ubd_set_bit(i, (unsigned char *) |
91acb21f JD |
1042 | &req->sector_mask); |
1043 | } | |
1044 | } | |
1045 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1046 | &req->cow_offset, bitmap, bitmap_offset, | |
1047 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1048 | } |
1049 | ||
62f96cb0 | 1050 | /* Called with dev->lock held */ |
a0044bdf JD |
1051 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1052 | unsigned long long offset, int page_offset, | |
1053 | int len, struct page *page) | |
1da177e4 LT |
1054 | { |
1055 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1056 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1057 | |
62f96cb0 | 1058 | io_req->req = req; |
a0044bdf JD |
1059 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1060 | ubd_dev->fd; | |
7d314e34 | 1061 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1062 | io_req->cow_offset = -1; |
1da177e4 LT |
1063 | io_req->offset = offset; |
1064 | io_req->length = len; | |
1065 | io_req->error = 0; | |
91acb21f JD |
1066 | io_req->sector_mask = 0; |
1067 | ||
1068 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1069 | io_req->offsets[0] = 0; |
7d314e34 | 1070 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1071 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1072 | io_req->sectorsize = 1 << 9; |
1073 | ||
7d314e34 | 1074 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1075 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1076 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1077 | |
1da177e4 LT |
1078 | } |
1079 | ||
62f96cb0 | 1080 | /* Called with dev->lock held */ |
1da177e4 LT |
1081 | static void do_ubd_request(request_queue_t *q) |
1082 | { | |
2adcec21 | 1083 | struct io_thread_req *io_req; |
1da177e4 | 1084 | struct request *req; |
a0044bdf JD |
1085 | int n; |
1086 | ||
1087 | while(1){ | |
2a9529a0 | 1088 | struct ubd *dev = q->queuedata; |
a0044bdf JD |
1089 | if(dev->end_sg == 0){ |
1090 | struct request *req = elv_next_request(q); | |
1091 | if(req == NULL) | |
1092 | return; | |
1093 | ||
1094 | dev->request = req; | |
1095 | blkdev_dequeue_request(req); | |
1096 | dev->start_sg = 0; | |
1097 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1098 | } | |
1099 | ||
1100 | req = dev->request; | |
1101 | while(dev->start_sg < dev->end_sg){ | |
1102 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1103 | ||
2adcec21 | 1104 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1105 | GFP_ATOMIC); |
2adcec21 JD |
1106 | if(io_req == NULL){ |
1107 | if(list_empty(&dev->restart)) | |
1108 | list_add(&dev->restart, &restart); | |
1109 | return; | |
1110 | } | |
1111 | prepare_request(req, io_req, | |
a0044bdf JD |
1112 | (unsigned long long) req->sector << 9, |
1113 | sg->offset, sg->length, sg->page); | |
1114 | ||
2adcec21 JD |
1115 | n = os_write_file_k(thread_fd, &io_req, |
1116 | sizeof(struct io_thread_req *)); | |
1117 | if(n != sizeof(struct io_thread_req *)){ | |
a0044bdf JD |
1118 | if(n != -EAGAIN) |
1119 | printk("write to io thread failed, " | |
1120 | "errno = %d\n", -n); | |
1121 | else if(list_empty(&dev->restart)) | |
1122 | list_add(&dev->restart, &restart); | |
1123 | return; | |
1124 | } | |
1125 | ||
1126 | req->sector += sg->length >> 9; | |
1127 | dev->start_sg++; | |
1da177e4 | 1128 | } |
a0044bdf JD |
1129 | dev->end_sg = 0; |
1130 | dev->request = NULL; | |
1da177e4 LT |
1131 | } |
1132 | } | |
1133 | ||
a885c8c4 CH |
1134 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1135 | { | |
7d314e34 | 1136 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1137 | |
1138 | geo->heads = 128; | |
1139 | geo->sectors = 32; | |
7d314e34 | 1140 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1141 | return 0; |
1142 | } | |
1143 | ||
1da177e4 LT |
1144 | static int ubd_ioctl(struct inode * inode, struct file * file, |
1145 | unsigned int cmd, unsigned long arg) | |
1146 | { | |
7d314e34 | 1147 | struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; |
1da177e4 LT |
1148 | struct hd_driveid ubd_id = { |
1149 | .cyls = 0, | |
1150 | .heads = 128, | |
1151 | .sectors = 32, | |
1152 | }; | |
1153 | ||
1154 | switch (cmd) { | |
1da177e4 | 1155 | struct cdrom_volctrl volume; |
1da177e4 | 1156 | case HDIO_GET_IDENTITY: |
7d314e34 | 1157 | ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); |
1da177e4 LT |
1158 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1159 | sizeof(ubd_id))) | |
1160 | return(-EFAULT); | |
1161 | return(0); | |
b8831a1d | 1162 | |
1da177e4 LT |
1163 | case CDROMVOLREAD: |
1164 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
1165 | return(-EFAULT); | |
1166 | volume.channel0 = 255; | |
1167 | volume.channel1 = 255; | |
1168 | volume.channel2 = 255; | |
1169 | volume.channel3 = 255; | |
1170 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
1171 | return(-EFAULT); | |
1172 | return(0); | |
1173 | } | |
1174 | return(-EINVAL); | |
1175 | } | |
1176 | ||
4833aff7 | 1177 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) |
1da177e4 LT |
1178 | { |
1179 | struct uml_stat buf1, buf2; | |
1180 | int err; | |
1181 | ||
4833aff7 PBG |
1182 | if(from_cmdline == NULL) |
1183 | return 0; | |
1184 | if(!strcmp(from_cmdline, from_cow)) | |
1185 | return 0; | |
1da177e4 LT |
1186 | |
1187 | err = os_stat_file(from_cmdline, &buf1); | |
1188 | if(err < 0){ | |
1189 | printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); | |
4833aff7 | 1190 | return 0; |
1da177e4 LT |
1191 | } |
1192 | err = os_stat_file(from_cow, &buf2); | |
1193 | if(err < 0){ | |
1194 | printk("Couldn't stat '%s', err = %d\n", from_cow, -err); | |
4833aff7 | 1195 | return 1; |
1da177e4 LT |
1196 | } |
1197 | if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
4833aff7 | 1198 | return 0; |
1da177e4 LT |
1199 | |
1200 | printk("Backing file mismatch - \"%s\" requested,\n" | |
1201 | "\"%s\" specified in COW header of \"%s\"\n", | |
1202 | from_cmdline, from_cow, cow); | |
4833aff7 | 1203 | return 1; |
1da177e4 LT |
1204 | } |
1205 | ||
1206 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
1207 | { | |
1208 | unsigned long modtime; | |
fe1db50c | 1209 | unsigned long long actual; |
1da177e4 LT |
1210 | int err; |
1211 | ||
1212 | err = os_file_modtime(file, &modtime); | |
1213 | if(err < 0){ | |
1214 | printk("Failed to get modification time of backing file " | |
1215 | "\"%s\", err = %d\n", file, -err); | |
1216 | return(err); | |
1217 | } | |
1218 | ||
1219 | err = os_file_size(file, &actual); | |
1220 | if(err < 0){ | |
1221 | printk("Failed to get size of backing file \"%s\", " | |
1222 | "err = %d\n", file, -err); | |
1223 | return(err); | |
1224 | } | |
1225 | ||
1226 | if(actual != size){ | |
1227 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
1228 | * the typecast.*/ | |
1229 | printk("Size mismatch (%llu vs %llu) of COW header vs backing " | |
1230 | "file\n", (unsigned long long) size, actual); | |
1231 | return(-EINVAL); | |
1232 | } | |
1233 | if(modtime != mtime){ | |
1234 | printk("mtime mismatch (%ld vs %ld) of COW header vs backing " | |
1235 | "file\n", mtime, modtime); | |
1236 | return(-EINVAL); | |
1237 | } | |
1238 | return(0); | |
1239 | } | |
1240 | ||
1241 | int read_cow_bitmap(int fd, void *buf, int offset, int len) | |
1242 | { | |
1243 | int err; | |
1244 | ||
1245 | err = os_seek_file(fd, offset); | |
1246 | if(err < 0) | |
1247 | return(err); | |
1248 | ||
fda83a99 | 1249 | err = os_read_file_k(fd, buf, len); |
1da177e4 LT |
1250 | if(err < 0) |
1251 | return(err); | |
1252 | ||
1253 | return(0); | |
1254 | } | |
1255 | ||
6c29256c | 1256 | int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
1257 | char **backing_file_out, int *bitmap_offset_out, |
1258 | unsigned long *bitmap_len_out, int *data_offset_out, | |
1259 | int *create_cow_out) | |
1260 | { | |
1261 | time_t mtime; | |
1262 | unsigned long long size; | |
1263 | __u32 version, align; | |
1264 | char *backing_file; | |
4833aff7 | 1265 | int fd, err, sectorsize, asked_switch, mode = 0644; |
1da177e4 LT |
1266 | |
1267 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1268 | if (fd < 0) { |
1269 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
1da177e4 | 1270 | *create_cow_out = 1; |
a374a48f PBG |
1271 | if (!openflags->w || |
1272 | ((fd != -EROFS) && (fd != -EACCES))) | |
1273 | return fd; | |
1da177e4 LT |
1274 | openflags->w = 0; |
1275 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1276 | if (fd < 0) |
1277 | return fd; | |
1da177e4 LT |
1278 | } |
1279 | ||
6c29256c JD |
1280 | if(shared) |
1281 | printk("Not locking \"%s\" on the host\n", file); | |
1282 | else { | |
1283 | err = os_lock_file(fd, openflags->w); | |
1284 | if(err < 0){ | |
1285 | printk("Failed to lock '%s', err = %d\n", file, -err); | |
1286 | goto out_close; | |
1287 | } | |
1da177e4 LT |
1288 | } |
1289 | ||
d6e05edc | 1290 | /* Successful return case! */ |
a374a48f PBG |
1291 | if(backing_file_out == NULL) |
1292 | return(fd); | |
1da177e4 LT |
1293 | |
1294 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
1295 | &size, §orsize, &align, bitmap_offset_out); | |
1296 | if(err && (*backing_file_out != NULL)){ | |
1297 | printk("Failed to read COW header from COW file \"%s\", " | |
1298 | "errno = %d\n", file, -err); | |
1299 | goto out_close; | |
1300 | } | |
a374a48f PBG |
1301 | if(err) |
1302 | return(fd); | |
1da177e4 | 1303 | |
4833aff7 | 1304 | asked_switch = path_requires_switch(*backing_file_out, backing_file, file); |
1da177e4 | 1305 | |
4833aff7 PBG |
1306 | /* Allow switching only if no mismatch. */ |
1307 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) { | |
1da177e4 LT |
1308 | printk("Switching backing file to '%s'\n", *backing_file_out); |
1309 | err = write_cow_header(file, fd, *backing_file_out, | |
1310 | sectorsize, align, &size); | |
a374a48f | 1311 | if (err) { |
1da177e4 | 1312 | printk("Switch failed, errno = %d\n", -err); |
4833aff7 | 1313 | goto out_close; |
1da177e4 | 1314 | } |
a374a48f | 1315 | } else { |
1da177e4 LT |
1316 | *backing_file_out = backing_file; |
1317 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
a374a48f PBG |
1318 | if (err) |
1319 | goto out_close; | |
1da177e4 LT |
1320 | } |
1321 | ||
1322 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
1323 | bitmap_len_out, data_offset_out); | |
1324 | ||
a374a48f | 1325 | return fd; |
1da177e4 LT |
1326 | out_close: |
1327 | os_close_file(fd); | |
a374a48f | 1328 | return err; |
1da177e4 LT |
1329 | } |
1330 | ||
1331 | int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, | |
1332 | int sectorsize, int alignment, int *bitmap_offset_out, | |
1333 | unsigned long *bitmap_len_out, int *data_offset_out) | |
1334 | { | |
1335 | int err, fd; | |
1336 | ||
1337 | flags.c = 1; | |
6c29256c | 1338 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); |
1da177e4 LT |
1339 | if(fd < 0){ |
1340 | err = fd; | |
1341 | printk("Open of COW file '%s' failed, errno = %d\n", cow_file, | |
1342 | -err); | |
1343 | goto out; | |
1344 | } | |
1345 | ||
1346 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
1347 | bitmap_offset_out, bitmap_len_out, | |
1348 | data_offset_out); | |
1349 | if(!err) | |
1350 | return(fd); | |
1351 | os_close_file(fd); | |
1352 | out: | |
1353 | return(err); | |
1354 | } | |
1355 | ||
91acb21f | 1356 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1357 | { |
91acb21f | 1358 | int n; |
1da177e4 | 1359 | |
91acb21f JD |
1360 | if(req->cow_offset == -1) |
1361 | return(0); | |
1da177e4 | 1362 | |
91acb21f JD |
1363 | n = os_seek_file(req->fds[1], req->cow_offset); |
1364 | if(n < 0){ | |
1365 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
1366 | return(1); | |
1367 | } | |
1da177e4 | 1368 | |
3d564047 JD |
1369 | n = os_write_file_k(req->fds[1], &req->bitmap_words, |
1370 | sizeof(req->bitmap_words)); | |
91acb21f JD |
1371 | if(n != sizeof(req->bitmap_words)){ |
1372 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1373 | req->fds[1]); | |
1374 | return(1); | |
1375 | } | |
1da177e4 | 1376 | |
91acb21f JD |
1377 | return(0); |
1378 | } | |
1da177e4 | 1379 | |
91acb21f JD |
1380 | void do_io(struct io_thread_req *req) |
1381 | { | |
1382 | char *buf; | |
1383 | unsigned long len; | |
1384 | int n, nsectors, start, end, bit; | |
1385 | int err; | |
1386 | __u64 off; | |
1387 | ||
1388 | nsectors = req->length / req->sectorsize; | |
1389 | start = 0; | |
1390 | do { | |
1391 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1392 | end = start; | |
1393 | while((end < nsectors) && | |
1394 | (ubd_test_bit(end, (unsigned char *) | |
1395 | &req->sector_mask) == bit)) | |
1396 | end++; | |
1397 | ||
1398 | off = req->offset + req->offsets[bit] + | |
1399 | start * req->sectorsize; | |
1400 | len = (end - start) * req->sectorsize; | |
1401 | buf = &req->buffer[start * req->sectorsize]; | |
1402 | ||
1403 | err = os_seek_file(req->fds[bit], off); | |
1404 | if(err < 0){ | |
1405 | printk("do_io - lseek failed : err = %d\n", -err); | |
1406 | req->error = 1; | |
1407 | return; | |
1408 | } | |
1409 | if(req->op == UBD_READ){ | |
1410 | n = 0; | |
1411 | do { | |
1412 | buf = &buf[n]; | |
1413 | len -= n; | |
3d564047 | 1414 | n = os_read_file_k(req->fds[bit], buf, len); |
91acb21f JD |
1415 | if (n < 0) { |
1416 | printk("do_io - read failed, err = %d " | |
1417 | "fd = %d\n", -n, req->fds[bit]); | |
1418 | req->error = 1; | |
1419 | return; | |
1420 | } | |
1421 | } while((n < len) && (n != 0)); | |
1422 | if (n < len) memset(&buf[n], 0, len - n); | |
1423 | } else { | |
3d564047 | 1424 | n = os_write_file_k(req->fds[bit], buf, len); |
91acb21f JD |
1425 | if(n != len){ |
1426 | printk("do_io - write failed err = %d " | |
1427 | "fd = %d\n", -n, req->fds[bit]); | |
1428 | req->error = 1; | |
1429 | return; | |
1430 | } | |
1431 | } | |
1432 | ||
1433 | start = end; | |
1434 | } while(start < nsectors); | |
1da177e4 | 1435 | |
91acb21f | 1436 | req->error = update_bitmap(req); |
1da177e4 | 1437 | } |
91acb21f JD |
1438 | |
1439 | /* Changed in start_io_thread, which is serialized by being called only | |
1440 | * from ubd_init, which is an initcall. | |
1441 | */ | |
1442 | int kernel_fd = -1; | |
1443 | ||
d8d7c28e PBG |
1444 | /* Only changed by the io thread. XXX: currently unused. */ |
1445 | static int io_count = 0; | |
91acb21f JD |
1446 | |
1447 | int io_thread(void *arg) | |
1448 | { | |
2adcec21 | 1449 | struct io_thread_req *req; |
91acb21f JD |
1450 | int n; |
1451 | ||
1452 | ignore_sigwinch_sig(); | |
1453 | while(1){ | |
2adcec21 JD |
1454 | n = os_read_file_k(kernel_fd, &req, |
1455 | sizeof(struct io_thread_req *)); | |
1456 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1457 | if(n < 0) |
1458 | printk("io_thread - read failed, fd = %d, " | |
1459 | "err = %d\n", kernel_fd, -n); | |
1460 | else { | |
1461 | printk("io_thread - short read, fd = %d, " | |
1462 | "length = %d\n", kernel_fd, n); | |
1463 | } | |
1464 | continue; | |
1465 | } | |
1466 | io_count++; | |
2adcec21 JD |
1467 | do_io(req); |
1468 | n = os_write_file_k(kernel_fd, &req, | |
1469 | sizeof(struct io_thread_req *)); | |
1470 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1471 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1472 | kernel_fd, -n); | |
1473 | } | |
91acb21f | 1474 | |
1b57e9c2 JD |
1475 | return 0; |
1476 | } |