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