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Commit | Line | Data |
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6c29256c | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
3 | * Licensed under the GPL | |
4 | */ | |
5 | ||
6 | /* 2001-09-28...2002-04-17 | |
7 | * Partition stuff by James_McMechan@hotmail.com | |
8 | * old style ubd by setting UBD_SHIFT to 0 | |
9 | * 2002-09-27...2002-10-18 massive tinkering for 2.5 | |
10 | * partitions have changed in 2.5 | |
11 | * 2003-01-29 more tinkering for 2.5.59-1 | |
12 | * This should now address the sysfs problems and has | |
13 | * the symlink for devfs to allow for booting with | |
14 | * the common /dev/ubd/discX/... names rather than | |
15 | * only /dev/ubdN/discN this version also has lots of | |
16 | * clean ups preparing for ubd-many. | |
17 | * James McMechan | |
18 | */ | |
19 | ||
20 | #define MAJOR_NR UBD_MAJOR | |
21 | #define UBD_SHIFT 4 | |
22 | ||
1da177e4 LT |
23 | #include "linux/module.h" |
24 | #include "linux/blkdev.h" | |
25 | #include "linux/hdreg.h" | |
26 | #include "linux/init.h" | |
1da177e4 LT |
27 | #include "linux/cdrom.h" |
28 | #include "linux/proc_fs.h" | |
29 | #include "linux/ctype.h" | |
30 | #include "linux/capability.h" | |
31 | #include "linux/mm.h" | |
32 | #include "linux/vmalloc.h" | |
33 | #include "linux/blkpg.h" | |
34 | #include "linux/genhd.h" | |
35 | #include "linux/spinlock.h" | |
d052d1be | 36 | #include "linux/platform_device.h" |
1da177e4 LT |
37 | #include "asm/segment.h" |
38 | #include "asm/uaccess.h" | |
39 | #include "asm/irq.h" | |
40 | #include "asm/types.h" | |
41 | #include "asm/tlbflush.h" | |
42 | #include "user_util.h" | |
43 | #include "mem_user.h" | |
44 | #include "kern_util.h" | |
45 | #include "kern.h" | |
46 | #include "mconsole_kern.h" | |
47 | #include "init.h" | |
48 | #include "irq_user.h" | |
49 | #include "irq_kern.h" | |
50 | #include "ubd_user.h" | |
1da177e4 LT |
51 | #include "os.h" |
52 | #include "mem.h" | |
53 | #include "mem_kern.h" | |
54 | #include "cow.h" | |
55 | ||
7b9014c1 | 56 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
57 | |
58 | struct io_thread_req { | |
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 | ||
109 | static DEFINE_SPINLOCK(ubd_io_lock); | |
110 | static DEFINE_SPINLOCK(ubd_lock); | |
111 | ||
91acb21f JD |
112 | static void (*do_ubd)(void); |
113 | ||
1da177e4 LT |
114 | static int ubd_open(struct inode * inode, struct file * filp); |
115 | static int ubd_release(struct inode * inode, struct file * file); | |
116 | static int ubd_ioctl(struct inode * inode, struct file * file, | |
117 | unsigned int cmd, unsigned long arg); | |
a885c8c4 | 118 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 119 | |
97d88ac8 | 120 | #define MAX_DEV (16) |
1da177e4 | 121 | |
1da177e4 LT |
122 | static struct block_device_operations ubd_blops = { |
123 | .owner = THIS_MODULE, | |
124 | .open = ubd_open, | |
125 | .release = ubd_release, | |
126 | .ioctl = ubd_ioctl, | |
a885c8c4 | 127 | .getgeo = ubd_getgeo, |
1da177e4 LT |
128 | }; |
129 | ||
130 | /* Protected by the queue_lock */ | |
131 | static request_queue_t *ubd_queue; | |
132 | ||
133 | /* Protected by ubd_lock */ | |
134 | static int fake_major = MAJOR_NR; | |
135 | ||
136 | static struct gendisk *ubd_gendisk[MAX_DEV]; | |
137 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 138 | |
1da177e4 LT |
139 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
140 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
141 | .cl = 1 }) | |
142 | #else | |
143 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
144 | .cl = 1 }) | |
145 | #endif | |
146 | ||
147 | /* Not protected - changed only in ubd_setup_common and then only to | |
148 | * to enable O_SYNC. | |
149 | */ | |
150 | static struct openflags global_openflags = OPEN_FLAGS; | |
151 | ||
152 | struct cow { | |
2a9d32f6 | 153 | /* backing file name */ |
1da177e4 | 154 | char *file; |
2a9d32f6 | 155 | /* backing file fd */ |
1da177e4 LT |
156 | int fd; |
157 | unsigned long *bitmap; | |
158 | unsigned long bitmap_len; | |
159 | int bitmap_offset; | |
160 | int data_offset; | |
161 | }; | |
162 | ||
163 | struct ubd { | |
2a9d32f6 PBG |
164 | /* name (and fd, below) of the file opened for writing, either the |
165 | * backing or the cow file. */ | |
1da177e4 LT |
166 | char *file; |
167 | int count; | |
168 | int fd; | |
169 | __u64 size; | |
170 | struct openflags boot_openflags; | |
171 | struct openflags openflags; | |
6c29256c | 172 | int shared; |
1da177e4 LT |
173 | int no_cow; |
174 | struct cow cow; | |
175 | struct platform_device pdev; | |
1da177e4 LT |
176 | }; |
177 | ||
178 | #define DEFAULT_COW { \ | |
179 | .file = NULL, \ | |
180 | .fd = -1, \ | |
181 | .bitmap = NULL, \ | |
182 | .bitmap_offset = 0, \ | |
183 | .data_offset = 0, \ | |
184 | } | |
185 | ||
186 | #define DEFAULT_UBD { \ | |
187 | .file = NULL, \ | |
188 | .count = 0, \ | |
189 | .fd = -1, \ | |
190 | .size = -1, \ | |
191 | .boot_openflags = OPEN_FLAGS, \ | |
192 | .openflags = OPEN_FLAGS, \ | |
193 | .no_cow = 0, \ | |
6c29256c | 194 | .shared = 0, \ |
1da177e4 | 195 | .cow = DEFAULT_COW, \ |
1da177e4 LT |
196 | } |
197 | ||
7d314e34 | 198 | struct ubd ubd_devs[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD }; |
1da177e4 LT |
199 | |
200 | static int ubd0_init(void) | |
201 | { | |
7d314e34 | 202 | struct ubd *ubd_dev = &ubd_devs[0]; |
1da177e4 | 203 | |
7d314e34 PBG |
204 | if(ubd_dev->file == NULL) |
205 | ubd_dev->file = "root_fs"; | |
1da177e4 LT |
206 | return(0); |
207 | } | |
208 | ||
209 | __initcall(ubd0_init); | |
210 | ||
211 | /* Only changed by fake_ide_setup which is a setup */ | |
212 | static int fake_ide = 0; | |
213 | static struct proc_dir_entry *proc_ide_root = NULL; | |
214 | static struct proc_dir_entry *proc_ide = NULL; | |
215 | ||
216 | static void make_proc_ide(void) | |
217 | { | |
218 | proc_ide_root = proc_mkdir("ide", NULL); | |
219 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
220 | } | |
221 | ||
222 | static int proc_ide_read_media(char *page, char **start, off_t off, int count, | |
223 | int *eof, void *data) | |
224 | { | |
225 | int len; | |
226 | ||
227 | strcpy(page, "disk\n"); | |
228 | len = strlen("disk\n"); | |
229 | len -= off; | |
230 | if (len < count){ | |
231 | *eof = 1; | |
232 | if (len <= 0) return 0; | |
233 | } | |
234 | else len = count; | |
235 | *start = page + off; | |
236 | return len; | |
237 | } | |
238 | ||
239 | static void make_ide_entries(char *dev_name) | |
240 | { | |
241 | struct proc_dir_entry *dir, *ent; | |
242 | char name[64]; | |
243 | ||
244 | if(proc_ide_root == NULL) make_proc_ide(); | |
245 | ||
246 | dir = proc_mkdir(dev_name, proc_ide); | |
247 | if(!dir) return; | |
248 | ||
249 | ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); | |
250 | if(!ent) return; | |
251 | ent->nlink = 1; | |
252 | ent->data = NULL; | |
253 | ent->read_proc = proc_ide_read_media; | |
254 | ent->write_proc = NULL; | |
255 | sprintf(name,"ide0/%s", dev_name); | |
256 | proc_symlink(dev_name, proc_ide_root, name); | |
257 | } | |
258 | ||
259 | static int fake_ide_setup(char *str) | |
260 | { | |
261 | fake_ide = 1; | |
262 | return(1); | |
263 | } | |
264 | ||
265 | __setup("fake_ide", fake_ide_setup); | |
266 | ||
267 | __uml_help(fake_ide_setup, | |
268 | "fake_ide\n" | |
269 | " Create ide0 entries that map onto ubd devices.\n\n" | |
270 | ); | |
271 | ||
272 | static int parse_unit(char **ptr) | |
273 | { | |
274 | char *str = *ptr, *end; | |
275 | int n = -1; | |
276 | ||
277 | if(isdigit(*str)) { | |
278 | n = simple_strtoul(str, &end, 0); | |
279 | if(end == str) | |
280 | return(-1); | |
281 | *ptr = end; | |
282 | } | |
97d88ac8 | 283 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
284 | n = *str - 'a'; |
285 | str++; | |
286 | *ptr = str; | |
287 | } | |
288 | return(n); | |
289 | } | |
290 | ||
291 | static int ubd_setup_common(char *str, int *index_out) | |
292 | { | |
7d314e34 | 293 | struct ubd *ubd_dev; |
1da177e4 LT |
294 | struct openflags flags = global_openflags; |
295 | char *backing_file; | |
296 | int n, err, i; | |
297 | ||
298 | if(index_out) *index_out = -1; | |
299 | n = *str; | |
300 | if(n == '='){ | |
301 | char *end; | |
302 | int major; | |
303 | ||
304 | str++; | |
1da177e4 LT |
305 | if(!strcmp(str, "sync")){ |
306 | global_openflags = of_sync(global_openflags); | |
307 | return(0); | |
308 | } | |
309 | major = simple_strtoul(str, &end, 0); | |
310 | if((*end != '\0') || (end == str)){ | |
6c29256c | 311 | printk(KERN_ERR |
1da177e4 LT |
312 | "ubd_setup : didn't parse major number\n"); |
313 | return(1); | |
314 | } | |
315 | ||
316 | err = 1; | |
317 | spin_lock(&ubd_lock); | |
318 | if(fake_major != MAJOR_NR){ | |
319 | printk(KERN_ERR "Can't assign a fake major twice\n"); | |
320 | goto out1; | |
321 | } | |
6c29256c | 322 | |
1da177e4 LT |
323 | fake_major = major; |
324 | ||
325 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
326 | major); | |
327 | err = 0; | |
328 | out1: | |
329 | spin_unlock(&ubd_lock); | |
330 | return(err); | |
331 | } | |
332 | ||
333 | n = parse_unit(&str); | |
334 | if(n < 0){ | |
335 | printk(KERN_ERR "ubd_setup : couldn't parse unit number " | |
336 | "'%s'\n", str); | |
337 | return(1); | |
338 | } | |
339 | if(n >= MAX_DEV){ | |
340 | printk(KERN_ERR "ubd_setup : index %d out of range " | |
341 | "(%d devices, from 0 to %d)\n", n, MAX_DEV, MAX_DEV - 1); | |
342 | return(1); | |
343 | } | |
344 | ||
345 | err = 1; | |
346 | spin_lock(&ubd_lock); | |
347 | ||
7d314e34 PBG |
348 | ubd_dev = &ubd_devs[n]; |
349 | if(ubd_dev->file != NULL){ | |
1da177e4 LT |
350 | printk(KERN_ERR "ubd_setup : device already configured\n"); |
351 | goto out; | |
352 | } | |
353 | ||
354 | if (index_out) | |
355 | *index_out = n; | |
356 | ||
6c29256c | 357 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
358 | switch (*str) { |
359 | case 'r': | |
360 | flags.w = 0; | |
361 | break; | |
362 | case 's': | |
363 | flags.s = 1; | |
364 | break; | |
365 | case 'd': | |
7d314e34 | 366 | ubd_dev->no_cow = 1; |
1da177e4 | 367 | break; |
6c29256c | 368 | case 'c': |
7d314e34 | 369 | ubd_dev->shared = 1; |
6c29256c | 370 | break; |
1da177e4 LT |
371 | case '=': |
372 | str++; | |
373 | goto break_loop; | |
374 | default: | |
6c29256c | 375 | printk(KERN_ERR "ubd_setup : Expected '=' or flag letter (r, s, c, or d)\n"); |
1da177e4 LT |
376 | goto out; |
377 | } | |
378 | str++; | |
379 | } | |
380 | ||
381 | if (*str == '=') | |
382 | printk(KERN_ERR "ubd_setup : Too many flags specified\n"); | |
383 | else | |
384 | printk(KERN_ERR "ubd_setup : Expected '='\n"); | |
385 | goto out; | |
386 | ||
387 | break_loop: | |
388 | err = 0; | |
389 | backing_file = strchr(str, ','); | |
390 | ||
391 | if (!backing_file) { | |
392 | backing_file = strchr(str, ':'); | |
393 | } | |
394 | ||
395 | if(backing_file){ | |
7d314e34 | 396 | if(ubd_dev->no_cow) |
1da177e4 LT |
397 | printk(KERN_ERR "Can't specify both 'd' and a " |
398 | "cow file\n"); | |
399 | else { | |
400 | *backing_file = '\0'; | |
401 | backing_file++; | |
402 | } | |
403 | } | |
7d314e34 PBG |
404 | ubd_dev->file = str; |
405 | ubd_dev->cow.file = backing_file; | |
406 | ubd_dev->boot_openflags = flags; | |
1da177e4 LT |
407 | out: |
408 | spin_unlock(&ubd_lock); | |
409 | return(err); | |
410 | } | |
411 | ||
412 | static int ubd_setup(char *str) | |
413 | { | |
414 | ubd_setup_common(str, NULL); | |
415 | return(1); | |
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" | |
427 | " When using only one filename, UML will detect whether to thread it like\n" | |
428 | " a COW file or a backing file. To override this detection, add the 'd'\n" | |
429 | " flag:\n" | |
430 | " ubd0d=BackingFile\n" | |
431 | " Usually, there is a filesystem in the file, but \n" | |
432 | " that's not required. Swap devices containing swap files can be\n" | |
433 | " specified like this. Also, a file which doesn't contain a\n" | |
434 | " filesystem can have its contents read in the virtual \n" | |
435 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
436 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
437 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
438 | " an 's' will cause data to be written to disk on the host immediately.\n\n" | |
439 | ); | |
440 | ||
441 | static int udb_setup(char *str) | |
442 | { | |
443 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
444 | "udb TYPO\n", str); | |
445 | return(1); | |
446 | } | |
447 | ||
448 | __setup("udb", udb_setup); | |
449 | __uml_help(udb_setup, | |
450 | "udb\n" | |
0894e27e JD |
451 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
452 | " to impossible to catch visually unless you specifically look for\n" | |
453 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
454 | " in the boot output.\n\n" |
455 | ); | |
456 | ||
457 | static int fakehd_set = 0; | |
458 | static int fakehd(char *str) | |
459 | { | |
460 | printk(KERN_INFO "fakehd : Changing ubd name to \"hd\".\n"); | |
461 | fakehd_set = 1; | |
462 | return 1; | |
463 | } | |
464 | ||
465 | __setup("fakehd", fakehd); | |
466 | __uml_help(fakehd, | |
467 | "fakehd\n" | |
468 | " Change the ubd device name to \"hd\".\n\n" | |
469 | ); | |
470 | ||
471 | static void do_ubd_request(request_queue_t * q); | |
91acb21f JD |
472 | |
473 | /* Only changed by ubd_init, which is an initcall. */ | |
474 | int thread_fd = -1; | |
1da177e4 LT |
475 | |
476 | /* Changed by ubd_handler, which is serialized because interrupts only | |
477 | * happen on CPU 0. | |
478 | */ | |
479 | int intr_count = 0; | |
480 | ||
91acb21f JD |
481 | /* call ubd_finish if you need to serialize */ |
482 | static void __ubd_finish(struct request *req, int error) | |
1da177e4 | 483 | { |
91acb21f JD |
484 | int nsect; |
485 | ||
486 | if(error){ | |
487 | end_request(req, 0); | |
488 | return; | |
1da177e4 | 489 | } |
91acb21f JD |
490 | nsect = req->current_nr_sectors; |
491 | req->sector += nsect; | |
492 | req->buffer += nsect << 9; | |
493 | req->errors = 0; | |
494 | req->nr_sectors -= nsect; | |
495 | req->current_nr_sectors = 0; | |
496 | end_request(req, 1); | |
1da177e4 LT |
497 | } |
498 | ||
91acb21f | 499 | static inline void ubd_finish(struct request *req, int error) |
1da177e4 | 500 | { |
91acb21f JD |
501 | spin_lock(&ubd_io_lock); |
502 | __ubd_finish(req, error); | |
503 | spin_unlock(&ubd_io_lock); | |
1da177e4 LT |
504 | } |
505 | ||
91acb21f JD |
506 | /* Called without ubd_io_lock held */ |
507 | static void ubd_handler(void) | |
1da177e4 | 508 | { |
91acb21f JD |
509 | struct io_thread_req req; |
510 | struct request *rq = elv_next_request(ubd_queue); | |
511 | int n; | |
512 | ||
513 | do_ubd = NULL; | |
514 | intr_count++; | |
515 | n = os_read_file(thread_fd, &req, sizeof(req)); | |
516 | if(n != sizeof(req)){ | |
517 | printk(KERN_ERR "Pid %d - spurious interrupt in ubd_handler, " | |
518 | "err = %d\n", os_getpid(), -n); | |
519 | spin_lock(&ubd_io_lock); | |
520 | end_request(rq, 0); | |
521 | spin_unlock(&ubd_io_lock); | |
522 | return; | |
523 | } | |
6c29256c | 524 | |
91acb21f JD |
525 | ubd_finish(rq, req.error); |
526 | reactivate_fd(thread_fd, UBD_IRQ); | |
527 | do_ubd_request(ubd_queue); | |
1da177e4 LT |
528 | } |
529 | ||
7bea96fd | 530 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 531 | { |
91acb21f JD |
532 | ubd_handler(); |
533 | return(IRQ_HANDLED); | |
534 | } | |
09ace81c | 535 | |
91acb21f JD |
536 | /* Only changed by ubd_init, which is an initcall. */ |
537 | static int io_pid = -1; | |
09ace81c | 538 | |
91acb21f JD |
539 | void kill_io_thread(void) |
540 | { | |
6c29256c | 541 | if(io_pid != -1) |
91acb21f | 542 | os_kill_process(io_pid, 1); |
09ace81c | 543 | } |
1da177e4 | 544 | |
91acb21f JD |
545 | __uml_exitcall(kill_io_thread); |
546 | ||
7d314e34 | 547 | static int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
548 | { |
549 | char *file; | |
550 | ||
7d314e34 | 551 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
1da177e4 LT |
552 | return(os_file_size(file, size_out)); |
553 | } | |
554 | ||
7d314e34 | 555 | static void ubd_close(struct ubd *ubd_dev) |
1da177e4 | 556 | { |
7d314e34 PBG |
557 | os_close_file(ubd_dev->fd); |
558 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
559 | return; |
560 | ||
7d314e34 PBG |
561 | os_close_file(ubd_dev->cow.fd); |
562 | vfree(ubd_dev->cow.bitmap); | |
563 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
564 | } |
565 | ||
7d314e34 | 566 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
567 | { |
568 | struct openflags flags; | |
569 | char **back_ptr; | |
570 | int err, create_cow, *create_ptr; | |
571 | ||
7d314e34 | 572 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 573 | create_cow = 0; |
7d314e34 PBG |
574 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
575 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
576 | ubd_dev->fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
577 | back_ptr, &ubd_dev->cow.bitmap_offset, | |
578 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 579 | create_ptr); |
1da177e4 | 580 | |
7d314e34 PBG |
581 | if((ubd_dev->fd == -ENOENT) && create_cow){ |
582 | ubd_dev->fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
583 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, | |
584 | &ubd_dev->cow.bitmap_offset, | |
585 | &ubd_dev->cow.bitmap_len, | |
586 | &ubd_dev->cow.data_offset); | |
587 | if(ubd_dev->fd >= 0){ | |
1da177e4 | 588 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 589 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
590 | } |
591 | } | |
592 | ||
7d314e34 PBG |
593 | if(ubd_dev->fd < 0){ |
594 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, | |
595 | -ubd_dev->fd); | |
596 | return(ubd_dev->fd); | |
1da177e4 LT |
597 | } |
598 | ||
7d314e34 | 599 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 600 | err = -ENOMEM; |
7d314e34 PBG |
601 | ubd_dev->cow.bitmap = (void *) vmalloc(ubd_dev->cow.bitmap_len); |
602 | if(ubd_dev->cow.bitmap == NULL){ | |
1da177e4 LT |
603 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
604 | goto error; | |
605 | } | |
606 | flush_tlb_kernel_vm(); | |
607 | ||
7d314e34 PBG |
608 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
609 | ubd_dev->cow.bitmap_offset, | |
610 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
611 | if(err < 0) |
612 | goto error; | |
613 | ||
7d314e34 | 614 | flags = ubd_dev->openflags; |
1da177e4 | 615 | flags.w = 0; |
7d314e34 | 616 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 617 | NULL, NULL, NULL, NULL); |
1da177e4 | 618 | if(err < 0) goto error; |
7d314e34 | 619 | ubd_dev->cow.fd = err; |
1da177e4 LT |
620 | } |
621 | return(0); | |
622 | error: | |
7d314e34 | 623 | os_close_file(ubd_dev->fd); |
1da177e4 LT |
624 | return(err); |
625 | } | |
626 | ||
627 | static int ubd_new_disk(int major, u64 size, int unit, | |
628 | struct gendisk **disk_out) | |
629 | ||
630 | { | |
631 | struct gendisk *disk; | |
1da177e4 LT |
632 | |
633 | disk = alloc_disk(1 << UBD_SHIFT); | |
634 | if(disk == NULL) | |
635 | return(-ENOMEM); | |
636 | ||
637 | disk->major = major; | |
638 | disk->first_minor = unit << UBD_SHIFT; | |
639 | disk->fops = &ubd_blops; | |
640 | set_capacity(disk, size / 512); | |
ce7b0f46 | 641 | if(major == MAJOR_NR) |
1da177e4 | 642 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 643 | else |
1da177e4 | 644 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
645 | |
646 | /* sysfs register (not for ide fake devices) */ | |
647 | if (major == MAJOR_NR) { | |
7d314e34 PBG |
648 | ubd_devs[unit].pdev.id = unit; |
649 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
650 | platform_device_register(&ubd_devs[unit].pdev); | |
651 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
652 | } |
653 | ||
7d314e34 | 654 | disk->private_data = &ubd_devs[unit]; |
1da177e4 LT |
655 | disk->queue = ubd_queue; |
656 | add_disk(disk); | |
657 | ||
658 | *disk_out = disk; | |
659 | return 0; | |
660 | } | |
661 | ||
662 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
663 | ||
664 | static int ubd_add(int n) | |
665 | { | |
7d314e34 | 666 | struct ubd *ubd_dev = &ubd_devs[n]; |
1da177e4 LT |
667 | int err; |
668 | ||
ec7cf783 | 669 | err = -ENODEV; |
7d314e34 | 670 | if(ubd_dev->file == NULL) |
ec7cf783 | 671 | goto out; |
1da177e4 | 672 | |
7d314e34 | 673 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
1da177e4 | 674 | if(err < 0) |
80c13749 | 675 | goto out; |
1da177e4 | 676 | |
7d314e34 | 677 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 678 | |
7d314e34 | 679 | err = ubd_new_disk(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); |
6c29256c | 680 | if(err) |
80c13749 | 681 | goto out; |
6c29256c | 682 | |
1da177e4 | 683 | if(fake_major != MAJOR_NR) |
7d314e34 | 684 | ubd_new_disk(fake_major, ubd_dev->size, n, |
1da177e4 LT |
685 | &fake_gendisk[n]); |
686 | ||
687 | /* perhaps this should also be under the "if (fake_major)" above */ | |
688 | /* using the fake_disk->disk_name and also the fakehd_set name */ | |
689 | if (fake_ide) | |
690 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
691 | ||
ec7cf783 | 692 | err = 0; |
ec7cf783 JD |
693 | out: |
694 | return err; | |
1da177e4 LT |
695 | } |
696 | ||
697 | static int ubd_config(char *str) | |
698 | { | |
699 | int n, err; | |
700 | ||
970d6e3a | 701 | str = kstrdup(str, GFP_KERNEL); |
1da177e4 LT |
702 | if(str == NULL){ |
703 | printk(KERN_ERR "ubd_config failed to strdup string\n"); | |
704 | return(1); | |
705 | } | |
706 | err = ubd_setup_common(str, &n); | |
707 | if(err){ | |
708 | kfree(str); | |
709 | return(-1); | |
710 | } | |
711 | if(n == -1) return(0); | |
712 | ||
713 | spin_lock(&ubd_lock); | |
714 | err = ubd_add(n); | |
715 | if(err) | |
7d314e34 | 716 | ubd_devs[n].file = NULL; |
1da177e4 LT |
717 | spin_unlock(&ubd_lock); |
718 | ||
719 | return(err); | |
720 | } | |
721 | ||
722 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
723 | { | |
7d314e34 | 724 | struct ubd *ubd_dev; |
1da177e4 LT |
725 | int n, len = 0; |
726 | ||
727 | n = parse_unit(&name); | |
728 | if((n >= MAX_DEV) || (n < 0)){ | |
729 | *error_out = "ubd_get_config : device number out of range"; | |
730 | return(-1); | |
731 | } | |
732 | ||
7d314e34 | 733 | ubd_dev = &ubd_devs[n]; |
1da177e4 LT |
734 | spin_lock(&ubd_lock); |
735 | ||
7d314e34 | 736 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
737 | CONFIG_CHUNK(str, size, len, "", 1); |
738 | goto out; | |
739 | } | |
740 | ||
7d314e34 | 741 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 742 | |
7d314e34 | 743 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 744 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 745 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
746 | } |
747 | else CONFIG_CHUNK(str, size, len, "", 1); | |
748 | ||
749 | out: | |
750 | spin_unlock(&ubd_lock); | |
751 | return(len); | |
752 | } | |
753 | ||
29d56cfe JD |
754 | static int ubd_id(char **str, int *start_out, int *end_out) |
755 | { | |
756 | int n; | |
757 | ||
758 | n = parse_unit(str); | |
759 | *start_out = 0; | |
760 | *end_out = MAX_DEV - 1; | |
761 | return n; | |
762 | } | |
763 | ||
764 | static int ubd_remove(int n) | |
1da177e4 | 765 | { |
7d314e34 | 766 | struct ubd *ubd_dev; |
29d56cfe | 767 | int err = -ENODEV; |
1da177e4 | 768 | |
29d56cfe | 769 | spin_lock(&ubd_lock); |
1da177e4 | 770 | |
29d56cfe JD |
771 | if(ubd_gendisk[n] == NULL) |
772 | goto out; | |
1da177e4 | 773 | |
7d314e34 | 774 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 775 | |
7d314e34 | 776 | if(ubd_dev->file == NULL) |
29d56cfe | 777 | goto out; |
1da177e4 | 778 | |
29d56cfe JD |
779 | /* you cannot remove a open disk */ |
780 | err = -EBUSY; | |
7d314e34 | 781 | if(ubd_dev->count > 0) |
1da177e4 LT |
782 | goto out; |
783 | ||
784 | del_gendisk(ubd_gendisk[n]); | |
785 | put_disk(ubd_gendisk[n]); | |
786 | ubd_gendisk[n] = NULL; | |
787 | ||
788 | if(fake_gendisk[n] != NULL){ | |
789 | del_gendisk(fake_gendisk[n]); | |
790 | put_disk(fake_gendisk[n]); | |
791 | fake_gendisk[n] = NULL; | |
792 | } | |
793 | ||
7d314e34 PBG |
794 | platform_device_unregister(&ubd_dev->pdev); |
795 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
1da177e4 | 796 | err = 0; |
29d56cfe JD |
797 | out: |
798 | spin_unlock(&ubd_lock); | |
799 | return err; | |
1da177e4 LT |
800 | } |
801 | ||
802 | static struct mc_device ubd_mc = { | |
803 | .name = "ubd", | |
804 | .config = ubd_config, | |
805 | .get_config = ubd_get_config, | |
29d56cfe | 806 | .id = ubd_id, |
1da177e4 LT |
807 | .remove = ubd_remove, |
808 | }; | |
809 | ||
810 | static int ubd_mc_init(void) | |
811 | { | |
812 | mconsole_register_dev(&ubd_mc); | |
813 | return 0; | |
814 | } | |
815 | ||
816 | __initcall(ubd_mc_init); | |
817 | ||
3ae5eaec RK |
818 | static struct platform_driver ubd_driver = { |
819 | .driver = { | |
820 | .name = DRIVER_NAME, | |
821 | }, | |
1da177e4 LT |
822 | }; |
823 | ||
824 | int ubd_init(void) | |
825 | { | |
826 | int i; | |
827 | ||
1da177e4 LT |
828 | if (register_blkdev(MAJOR_NR, "ubd")) |
829 | return -1; | |
830 | ||
831 | ubd_queue = blk_init_queue(do_ubd_request, &ubd_io_lock); | |
832 | if (!ubd_queue) { | |
833 | unregister_blkdev(MAJOR_NR, "ubd"); | |
834 | return -1; | |
835 | } | |
836 | ||
837 | if (fake_major != MAJOR_NR) { | |
838 | char name[sizeof("ubd_nnn\0")]; | |
839 | ||
840 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
841 | if (register_blkdev(fake_major, "ubd")) |
842 | return -1; | |
843 | } | |
3ae5eaec | 844 | platform_driver_register(&ubd_driver); |
6c29256c | 845 | for (i = 0; i < MAX_DEV; i++) |
1da177e4 LT |
846 | ubd_add(i); |
847 | return 0; | |
848 | } | |
849 | ||
850 | late_initcall(ubd_init); | |
851 | ||
91acb21f JD |
852 | int ubd_driver_init(void){ |
853 | unsigned long stack; | |
854 | int err; | |
855 | ||
856 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
857 | if(global_openflags.s){ | |
858 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
859 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
860 | * enough. So use anyway the io thread. */ | |
861 | } | |
862 | stack = alloc_stack(0, 0); | |
6c29256c | 863 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
864 | &thread_fd); |
865 | if(io_pid < 0){ | |
6c29256c | 866 | printk(KERN_ERR |
91acb21f JD |
867 | "ubd : Failed to start I/O thread (errno = %d) - " |
868 | "falling back to synchronous I/O\n", -io_pid); | |
869 | io_pid = -1; | |
870 | return(0); | |
871 | } | |
6c29256c | 872 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 873 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
874 | if(err != 0) |
875 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 876 | return 0; |
91acb21f JD |
877 | } |
878 | ||
879 | device_initcall(ubd_driver_init); | |
880 | ||
1da177e4 LT |
881 | static int ubd_open(struct inode *inode, struct file *filp) |
882 | { | |
883 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 884 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
885 | int err = 0; |
886 | ||
7d314e34 PBG |
887 | if(ubd_dev->count == 0){ |
888 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
889 | if(err){ |
890 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 891 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
892 | goto out; |
893 | } | |
894 | } | |
7d314e34 PBG |
895 | ubd_dev->count++; |
896 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
897 | |
898 | /* This should no more be needed. And it didn't work anyway to exclude | |
899 | * read-write remounting of filesystems.*/ | |
7d314e34 PBG |
900 | /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
901 | if(--ubd_dev->count == 0) ubd_close(ubd_dev); | |
1da177e4 | 902 | err = -EROFS; |
2c49be99 | 903 | }*/ |
1da177e4 LT |
904 | out: |
905 | return(err); | |
906 | } | |
907 | ||
908 | static int ubd_release(struct inode * inode, struct file * file) | |
909 | { | |
910 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 911 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 912 | |
7d314e34 PBG |
913 | if(--ubd_dev->count == 0) |
914 | ubd_close(ubd_dev); | |
1da177e4 LT |
915 | return(0); |
916 | } | |
917 | ||
91acb21f JD |
918 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
919 | __u64 *cow_offset, unsigned long *bitmap, | |
920 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
921 | __u64 bitmap_len) | |
1da177e4 | 922 | { |
91acb21f JD |
923 | __u64 sector = io_offset >> 9; |
924 | int i, update_bitmap = 0; | |
925 | ||
926 | for(i = 0; i < length >> 9; i++){ | |
927 | if(cow_mask != NULL) | |
928 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
929 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
930 | continue; | |
1da177e4 | 931 | |
91acb21f JD |
932 | update_bitmap = 1; |
933 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
934 | } | |
935 | ||
936 | if(!update_bitmap) | |
937 | return; | |
1da177e4 | 938 | |
91acb21f | 939 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 940 | |
91acb21f JD |
941 | /* This takes care of the case where we're exactly at the end of the |
942 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
943 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
944 | * for the original diagnosis. | |
945 | */ | |
946 | if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / | |
947 | sizeof(unsigned long) - 1)) | |
948 | (*cow_offset)--; | |
949 | ||
950 | bitmap_words[0] = bitmap[*cow_offset]; | |
951 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
952 | ||
953 | *cow_offset *= sizeof(unsigned long); | |
954 | *cow_offset += bitmap_offset; | |
955 | } | |
956 | ||
957 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
958 | __u64 bitmap_offset, __u64 bitmap_len) | |
959 | { | |
960 | __u64 sector = req->offset >> 9; | |
961 | int i; | |
962 | ||
963 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
964 | panic("Operation too long"); | |
965 | ||
966 | if(req->op == UBD_READ) { | |
967 | for(i = 0; i < req->length >> 9; i++){ | |
968 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 969 | ubd_set_bit(i, (unsigned char *) |
91acb21f JD |
970 | &req->sector_mask); |
971 | } | |
972 | } | |
973 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
974 | &req->cow_offset, bitmap, bitmap_offset, | |
975 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
976 | } |
977 | ||
1da177e4 | 978 | /* Called with ubd_io_lock held */ |
91acb21f | 979 | static int prepare_request(struct request *req, struct io_thread_req *io_req) |
1da177e4 LT |
980 | { |
981 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 982 | struct ubd *ubd_dev = disk->private_data; |
91acb21f JD |
983 | __u64 offset; |
984 | int len; | |
985 | ||
2c49be99 | 986 | /* This should be impossible now */ |
7d314e34 | 987 | if((rq_data_dir(req) == WRITE) && !ubd_dev->openflags.w){ |
6c29256c | 988 | printk("Write attempted on readonly ubd device %s\n", |
1da177e4 | 989 | disk->disk_name); |
91acb21f | 990 | end_request(req, 0); |
1da177e4 LT |
991 | return(1); |
992 | } | |
993 | ||
91acb21f JD |
994 | offset = ((__u64) req->sector) << 9; |
995 | len = req->current_nr_sectors << 9; | |
996 | ||
7d314e34 PBG |
997 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : ubd_dev->fd; |
998 | io_req->fds[1] = ubd_dev->fd; | |
91acb21f | 999 | io_req->cow_offset = -1; |
1da177e4 LT |
1000 | io_req->offset = offset; |
1001 | io_req->length = len; | |
1002 | io_req->error = 0; | |
91acb21f JD |
1003 | io_req->sector_mask = 0; |
1004 | ||
1005 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1006 | io_req->offsets[0] = 0; |
7d314e34 | 1007 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
91acb21f | 1008 | io_req->buffer = req->buffer; |
1da177e4 LT |
1009 | io_req->sectorsize = 1 << 9; |
1010 | ||
7d314e34 PBG |
1011 | if(ubd_dev->cow.file != NULL) |
1012 | cowify_req(io_req, ubd_dev->cow.bitmap, ubd_dev->cow.bitmap_offset, | |
1013 | ubd_dev->cow.bitmap_len); | |
91acb21f | 1014 | |
1da177e4 LT |
1015 | return(0); |
1016 | } | |
1017 | ||
1018 | /* Called with ubd_io_lock held */ | |
1019 | static void do_ubd_request(request_queue_t *q) | |
1020 | { | |
1021 | struct io_thread_req io_req; | |
1022 | struct request *req; | |
91acb21f JD |
1023 | int err, n; |
1024 | ||
1025 | if(thread_fd == -1){ | |
1026 | while((req = elv_next_request(q)) != NULL){ | |
1027 | err = prepare_request(req, &io_req); | |
1028 | if(!err){ | |
1029 | do_io(&io_req); | |
1030 | __ubd_finish(req, io_req.error); | |
1031 | } | |
1032 | } | |
1033 | } | |
1034 | else { | |
1035 | if(do_ubd || (req = elv_next_request(q)) == NULL) | |
1036 | return; | |
1037 | err = prepare_request(req, &io_req); | |
1038 | if(!err){ | |
1039 | do_ubd = ubd_handler; | |
1040 | n = os_write_file(thread_fd, (char *) &io_req, | |
1041 | sizeof(io_req)); | |
1042 | if(n != sizeof(io_req)) | |
1043 | printk("write to io thread failed, " | |
1044 | "errno = %d\n", -n); | |
1da177e4 LT |
1045 | } |
1046 | } | |
1047 | } | |
1048 | ||
a885c8c4 CH |
1049 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1050 | { | |
7d314e34 | 1051 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1052 | |
1053 | geo->heads = 128; | |
1054 | geo->sectors = 32; | |
7d314e34 | 1055 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1056 | return 0; |
1057 | } | |
1058 | ||
1da177e4 LT |
1059 | static int ubd_ioctl(struct inode * inode, struct file * file, |
1060 | unsigned int cmd, unsigned long arg) | |
1061 | { | |
7d314e34 | 1062 | struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; |
1da177e4 LT |
1063 | struct hd_driveid ubd_id = { |
1064 | .cyls = 0, | |
1065 | .heads = 128, | |
1066 | .sectors = 32, | |
1067 | }; | |
1068 | ||
1069 | switch (cmd) { | |
1da177e4 | 1070 | struct cdrom_volctrl volume; |
1da177e4 | 1071 | case HDIO_GET_IDENTITY: |
7d314e34 | 1072 | ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); |
1da177e4 LT |
1073 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1074 | sizeof(ubd_id))) | |
1075 | return(-EFAULT); | |
1076 | return(0); | |
1077 | ||
1078 | case CDROMVOLREAD: | |
1079 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
1080 | return(-EFAULT); | |
1081 | volume.channel0 = 255; | |
1082 | volume.channel1 = 255; | |
1083 | volume.channel2 = 255; | |
1084 | volume.channel3 = 255; | |
1085 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
1086 | return(-EFAULT); | |
1087 | return(0); | |
1088 | } | |
1089 | return(-EINVAL); | |
1090 | } | |
1091 | ||
4833aff7 | 1092 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) |
1da177e4 LT |
1093 | { |
1094 | struct uml_stat buf1, buf2; | |
1095 | int err; | |
1096 | ||
4833aff7 PBG |
1097 | if(from_cmdline == NULL) |
1098 | return 0; | |
1099 | if(!strcmp(from_cmdline, from_cow)) | |
1100 | return 0; | |
1da177e4 LT |
1101 | |
1102 | err = os_stat_file(from_cmdline, &buf1); | |
1103 | if(err < 0){ | |
1104 | printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); | |
4833aff7 | 1105 | return 0; |
1da177e4 LT |
1106 | } |
1107 | err = os_stat_file(from_cow, &buf2); | |
1108 | if(err < 0){ | |
1109 | printk("Couldn't stat '%s', err = %d\n", from_cow, -err); | |
4833aff7 | 1110 | return 1; |
1da177e4 LT |
1111 | } |
1112 | if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
4833aff7 | 1113 | return 0; |
1da177e4 LT |
1114 | |
1115 | printk("Backing file mismatch - \"%s\" requested,\n" | |
1116 | "\"%s\" specified in COW header of \"%s\"\n", | |
1117 | from_cmdline, from_cow, cow); | |
4833aff7 | 1118 | return 1; |
1da177e4 LT |
1119 | } |
1120 | ||
1121 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
1122 | { | |
1123 | unsigned long modtime; | |
fe1db50c | 1124 | unsigned long long actual; |
1da177e4 LT |
1125 | int err; |
1126 | ||
1127 | err = os_file_modtime(file, &modtime); | |
1128 | if(err < 0){ | |
1129 | printk("Failed to get modification time of backing file " | |
1130 | "\"%s\", err = %d\n", file, -err); | |
1131 | return(err); | |
1132 | } | |
1133 | ||
1134 | err = os_file_size(file, &actual); | |
1135 | if(err < 0){ | |
1136 | printk("Failed to get size of backing file \"%s\", " | |
1137 | "err = %d\n", file, -err); | |
1138 | return(err); | |
1139 | } | |
1140 | ||
1141 | if(actual != size){ | |
1142 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
1143 | * the typecast.*/ | |
1144 | printk("Size mismatch (%llu vs %llu) of COW header vs backing " | |
1145 | "file\n", (unsigned long long) size, actual); | |
1146 | return(-EINVAL); | |
1147 | } | |
1148 | if(modtime != mtime){ | |
1149 | printk("mtime mismatch (%ld vs %ld) of COW header vs backing " | |
1150 | "file\n", mtime, modtime); | |
1151 | return(-EINVAL); | |
1152 | } | |
1153 | return(0); | |
1154 | } | |
1155 | ||
1156 | int read_cow_bitmap(int fd, void *buf, int offset, int len) | |
1157 | { | |
1158 | int err; | |
1159 | ||
1160 | err = os_seek_file(fd, offset); | |
1161 | if(err < 0) | |
1162 | return(err); | |
1163 | ||
1164 | err = os_read_file(fd, buf, len); | |
1165 | if(err < 0) | |
1166 | return(err); | |
1167 | ||
1168 | return(0); | |
1169 | } | |
1170 | ||
6c29256c | 1171 | int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
1172 | char **backing_file_out, int *bitmap_offset_out, |
1173 | unsigned long *bitmap_len_out, int *data_offset_out, | |
1174 | int *create_cow_out) | |
1175 | { | |
1176 | time_t mtime; | |
1177 | unsigned long long size; | |
1178 | __u32 version, align; | |
1179 | char *backing_file; | |
4833aff7 | 1180 | int fd, err, sectorsize, asked_switch, mode = 0644; |
1da177e4 LT |
1181 | |
1182 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1183 | if (fd < 0) { |
1184 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
1da177e4 | 1185 | *create_cow_out = 1; |
a374a48f PBG |
1186 | if (!openflags->w || |
1187 | ((fd != -EROFS) && (fd != -EACCES))) | |
1188 | return fd; | |
1da177e4 LT |
1189 | openflags->w = 0; |
1190 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1191 | if (fd < 0) |
1192 | return fd; | |
1da177e4 LT |
1193 | } |
1194 | ||
6c29256c JD |
1195 | if(shared) |
1196 | printk("Not locking \"%s\" on the host\n", file); | |
1197 | else { | |
1198 | err = os_lock_file(fd, openflags->w); | |
1199 | if(err < 0){ | |
1200 | printk("Failed to lock '%s', err = %d\n", file, -err); | |
1201 | goto out_close; | |
1202 | } | |
1da177e4 LT |
1203 | } |
1204 | ||
d6e05edc | 1205 | /* Successful return case! */ |
a374a48f PBG |
1206 | if(backing_file_out == NULL) |
1207 | return(fd); | |
1da177e4 LT |
1208 | |
1209 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
1210 | &size, §orsize, &align, bitmap_offset_out); | |
1211 | if(err && (*backing_file_out != NULL)){ | |
1212 | printk("Failed to read COW header from COW file \"%s\", " | |
1213 | "errno = %d\n", file, -err); | |
1214 | goto out_close; | |
1215 | } | |
a374a48f PBG |
1216 | if(err) |
1217 | return(fd); | |
1da177e4 | 1218 | |
4833aff7 | 1219 | asked_switch = path_requires_switch(*backing_file_out, backing_file, file); |
1da177e4 | 1220 | |
4833aff7 PBG |
1221 | /* Allow switching only if no mismatch. */ |
1222 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) { | |
1da177e4 LT |
1223 | printk("Switching backing file to '%s'\n", *backing_file_out); |
1224 | err = write_cow_header(file, fd, *backing_file_out, | |
1225 | sectorsize, align, &size); | |
a374a48f | 1226 | if (err) { |
1da177e4 | 1227 | printk("Switch failed, errno = %d\n", -err); |
4833aff7 | 1228 | goto out_close; |
1da177e4 | 1229 | } |
a374a48f | 1230 | } else { |
1da177e4 LT |
1231 | *backing_file_out = backing_file; |
1232 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
a374a48f PBG |
1233 | if (err) |
1234 | goto out_close; | |
1da177e4 LT |
1235 | } |
1236 | ||
1237 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
1238 | bitmap_len_out, data_offset_out); | |
1239 | ||
a374a48f | 1240 | return fd; |
1da177e4 LT |
1241 | out_close: |
1242 | os_close_file(fd); | |
a374a48f | 1243 | return err; |
1da177e4 LT |
1244 | } |
1245 | ||
1246 | int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, | |
1247 | int sectorsize, int alignment, int *bitmap_offset_out, | |
1248 | unsigned long *bitmap_len_out, int *data_offset_out) | |
1249 | { | |
1250 | int err, fd; | |
1251 | ||
1252 | flags.c = 1; | |
6c29256c | 1253 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); |
1da177e4 LT |
1254 | if(fd < 0){ |
1255 | err = fd; | |
1256 | printk("Open of COW file '%s' failed, errno = %d\n", cow_file, | |
1257 | -err); | |
1258 | goto out; | |
1259 | } | |
1260 | ||
1261 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
1262 | bitmap_offset_out, bitmap_len_out, | |
1263 | data_offset_out); | |
1264 | if(!err) | |
1265 | return(fd); | |
1266 | os_close_file(fd); | |
1267 | out: | |
1268 | return(err); | |
1269 | } | |
1270 | ||
91acb21f | 1271 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1272 | { |
91acb21f | 1273 | int n; |
1da177e4 | 1274 | |
91acb21f JD |
1275 | if(req->cow_offset == -1) |
1276 | return(0); | |
1da177e4 | 1277 | |
91acb21f JD |
1278 | n = os_seek_file(req->fds[1], req->cow_offset); |
1279 | if(n < 0){ | |
1280 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
1281 | return(1); | |
1282 | } | |
1da177e4 | 1283 | |
91acb21f JD |
1284 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1285 | sizeof(req->bitmap_words)); | |
1286 | if(n != sizeof(req->bitmap_words)){ | |
1287 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1288 | req->fds[1]); | |
1289 | return(1); | |
1290 | } | |
1da177e4 | 1291 | |
91acb21f JD |
1292 | return(0); |
1293 | } | |
1da177e4 | 1294 | |
91acb21f JD |
1295 | void do_io(struct io_thread_req *req) |
1296 | { | |
1297 | char *buf; | |
1298 | unsigned long len; | |
1299 | int n, nsectors, start, end, bit; | |
1300 | int err; | |
1301 | __u64 off; | |
1302 | ||
1303 | nsectors = req->length / req->sectorsize; | |
1304 | start = 0; | |
1305 | do { | |
1306 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1307 | end = start; | |
1308 | while((end < nsectors) && | |
1309 | (ubd_test_bit(end, (unsigned char *) | |
1310 | &req->sector_mask) == bit)) | |
1311 | end++; | |
1312 | ||
1313 | off = req->offset + req->offsets[bit] + | |
1314 | start * req->sectorsize; | |
1315 | len = (end - start) * req->sectorsize; | |
1316 | buf = &req->buffer[start * req->sectorsize]; | |
1317 | ||
1318 | err = os_seek_file(req->fds[bit], off); | |
1319 | if(err < 0){ | |
1320 | printk("do_io - lseek failed : err = %d\n", -err); | |
1321 | req->error = 1; | |
1322 | return; | |
1323 | } | |
1324 | if(req->op == UBD_READ){ | |
1325 | n = 0; | |
1326 | do { | |
1327 | buf = &buf[n]; | |
1328 | len -= n; | |
1329 | n = os_read_file(req->fds[bit], buf, len); | |
1330 | if (n < 0) { | |
1331 | printk("do_io - read failed, err = %d " | |
1332 | "fd = %d\n", -n, req->fds[bit]); | |
1333 | req->error = 1; | |
1334 | return; | |
1335 | } | |
1336 | } while((n < len) && (n != 0)); | |
1337 | if (n < len) memset(&buf[n], 0, len - n); | |
1338 | } else { | |
1339 | n = os_write_file(req->fds[bit], buf, len); | |
1340 | if(n != len){ | |
1341 | printk("do_io - write failed err = %d " | |
1342 | "fd = %d\n", -n, req->fds[bit]); | |
1343 | req->error = 1; | |
1344 | return; | |
1345 | } | |
1346 | } | |
1347 | ||
1348 | start = end; | |
1349 | } while(start < nsectors); | |
1da177e4 | 1350 | |
91acb21f | 1351 | req->error = update_bitmap(req); |
1da177e4 | 1352 | } |
91acb21f JD |
1353 | |
1354 | /* Changed in start_io_thread, which is serialized by being called only | |
1355 | * from ubd_init, which is an initcall. | |
1356 | */ | |
1357 | int kernel_fd = -1; | |
1358 | ||
1359 | /* Only changed by the io thread */ | |
1360 | int io_count = 0; | |
1361 | ||
1362 | int io_thread(void *arg) | |
1363 | { | |
1364 | struct io_thread_req req; | |
1365 | int n; | |
1366 | ||
1367 | ignore_sigwinch_sig(); | |
1368 | while(1){ | |
1369 | n = os_read_file(kernel_fd, &req, sizeof(req)); | |
1370 | if(n != sizeof(req)){ | |
1371 | if(n < 0) | |
1372 | printk("io_thread - read failed, fd = %d, " | |
1373 | "err = %d\n", kernel_fd, -n); | |
1374 | else { | |
1375 | printk("io_thread - short read, fd = %d, " | |
1376 | "length = %d\n", kernel_fd, n); | |
1377 | } | |
1378 | continue; | |
1379 | } | |
1380 | io_count++; | |
1381 | do_io(&req); | |
1382 | n = os_write_file(kernel_fd, &req, sizeof(req)); | |
1383 | if(n != sizeof(req)) | |
1384 | printk("io_thread - write failed, fd = %d, err = %d\n", | |
1385 | kernel_fd, -n); | |
1386 | } | |
91acb21f | 1387 | |
1b57e9c2 JD |
1388 | return 0; |
1389 | } |