Commit | Line | Data |
---|---|---|
6c29256c | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
3 | * Licensed under the GPL | |
4 | */ | |
5 | ||
6 | /* 2001-09-28...2002-04-17 | |
7 | * Partition stuff by James_McMechan@hotmail.com | |
8 | * old style ubd by setting UBD_SHIFT to 0 | |
9 | * 2002-09-27...2002-10-18 massive tinkering for 2.5 | |
10 | * partitions have changed in 2.5 | |
11 | * 2003-01-29 more tinkering for 2.5.59-1 | |
12 | * This should now address the sysfs problems and has | |
13 | * the symlink for devfs to allow for booting with | |
14 | * the common /dev/ubd/discX/... names rather than | |
15 | * only /dev/ubdN/discN this version also has lots of | |
16 | * clean ups preparing for ubd-many. | |
17 | * James McMechan | |
18 | */ | |
19 | ||
20 | #define MAJOR_NR UBD_MAJOR | |
21 | #define UBD_SHIFT 4 | |
22 | ||
e16f5350 | 23 | #include "linux/kernel.h" |
1da177e4 LT |
24 | #include "linux/module.h" |
25 | #include "linux/blkdev.h" | |
26 | #include "linux/hdreg.h" | |
27 | #include "linux/init.h" | |
1da177e4 LT |
28 | #include "linux/cdrom.h" |
29 | #include "linux/proc_fs.h" | |
30 | #include "linux/ctype.h" | |
31 | #include "linux/capability.h" | |
32 | #include "linux/mm.h" | |
33 | #include "linux/vmalloc.h" | |
34 | #include "linux/blkpg.h" | |
35 | #include "linux/genhd.h" | |
36 | #include "linux/spinlock.h" | |
d052d1be | 37 | #include "linux/platform_device.h" |
23464ffa | 38 | #include "linux/scatterlist.h" |
1da177e4 LT |
39 | #include "asm/segment.h" |
40 | #include "asm/uaccess.h" | |
41 | #include "asm/irq.h" | |
42 | #include "asm/types.h" | |
43 | #include "asm/tlbflush.h" | |
1da177e4 LT |
44 | #include "mem_user.h" |
45 | #include "kern_util.h" | |
46 | #include "kern.h" | |
47 | #include "mconsole_kern.h" | |
48 | #include "init.h" | |
49 | #include "irq_user.h" | |
50 | #include "irq_kern.h" | |
51 | #include "ubd_user.h" | |
edea1385 | 52 | #include "kern_util.h" |
1da177e4 LT |
53 | #include "os.h" |
54 | #include "mem.h" | |
55 | #include "mem_kern.h" | |
56 | #include "cow.h" | |
57 | ||
7b9014c1 | 58 | enum ubd_req { UBD_READ, UBD_WRITE }; |
1da177e4 LT |
59 | |
60 | struct io_thread_req { | |
62f96cb0 | 61 | struct request *req; |
91acb21f | 62 | enum ubd_req op; |
1da177e4 LT |
63 | int fds[2]; |
64 | unsigned long offsets[2]; | |
65 | unsigned long long offset; | |
66 | unsigned long length; | |
67 | char *buffer; | |
68 | int sectorsize; | |
91acb21f JD |
69 | unsigned long sector_mask; |
70 | unsigned long long cow_offset; | |
71 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
72 | int error; |
73 | }; | |
74 | ||
6c29256c | 75 | extern int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
76 | char **backing_file_out, int *bitmap_offset_out, |
77 | unsigned long *bitmap_len_out, int *data_offset_out, | |
78 | int *create_cow_out); | |
79 | extern int create_cow_file(char *cow_file, char *backing_file, | |
80 | struct openflags flags, int sectorsize, | |
81 | int alignment, int *bitmap_offset_out, | |
82 | unsigned long *bitmap_len_out, | |
83 | int *data_offset_out); | |
84 | extern int read_cow_bitmap(int fd, void *buf, int offset, int len); | |
91acb21f | 85 | extern void do_io(struct io_thread_req *req); |
1da177e4 | 86 | |
91acb21f | 87 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
88 | { |
89 | __u64 n; | |
90 | int bits, off; | |
91 | ||
91acb21f | 92 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
93 | n = bit / bits; |
94 | off = bit % bits; | |
dc764e50 | 95 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
96 | } |
97 | ||
91acb21f | 98 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
99 | { |
100 | __u64 n; | |
101 | int bits, off; | |
102 | ||
91acb21f | 103 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
104 | n = bit / bits; |
105 | off = bit % bits; | |
91acb21f | 106 | data[n] |= (1 << off); |
1da177e4 LT |
107 | } |
108 | /*End stuff from ubd_user.h*/ | |
109 | ||
110 | #define DRIVER_NAME "uml-blkdev" | |
111 | ||
d7fb2c38 | 112 | static DEFINE_MUTEX(ubd_lock); |
1da177e4 | 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 | ||
1da177e4 LT |
130 | /* Protected by ubd_lock */ |
131 | static int fake_major = MAJOR_NR; | |
1da177e4 LT |
132 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
133 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 134 | |
1da177e4 LT |
135 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
136 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
137 | .cl = 1 }) | |
138 | #else | |
139 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
140 | .cl = 1 }) | |
141 | #endif | |
1da177e4 LT |
142 | static struct openflags global_openflags = OPEN_FLAGS; |
143 | ||
144 | struct cow { | |
2a9d32f6 | 145 | /* backing file name */ |
1da177e4 | 146 | char *file; |
2a9d32f6 | 147 | /* backing file fd */ |
1da177e4 LT |
148 | int fd; |
149 | unsigned long *bitmap; | |
150 | unsigned long bitmap_len; | |
151 | int bitmap_offset; | |
dc764e50 | 152 | int data_offset; |
1da177e4 LT |
153 | }; |
154 | ||
a0044bdf JD |
155 | #define MAX_SG 64 |
156 | ||
1da177e4 | 157 | struct ubd { |
a0044bdf | 158 | struct list_head restart; |
2a9d32f6 PBG |
159 | /* name (and fd, below) of the file opened for writing, either the |
160 | * backing or the cow file. */ | |
1da177e4 LT |
161 | char *file; |
162 | int count; | |
163 | int fd; | |
164 | __u64 size; | |
165 | struct openflags boot_openflags; | |
166 | struct openflags openflags; | |
84e945e3 PBG |
167 | unsigned shared:1; |
168 | unsigned no_cow:1; | |
1da177e4 LT |
169 | struct cow cow; |
170 | struct platform_device pdev; | |
62f96cb0 JD |
171 | struct request_queue *queue; |
172 | spinlock_t lock; | |
a0044bdf JD |
173 | struct scatterlist sg[MAX_SG]; |
174 | struct request *request; | |
175 | int start_sg, end_sg; | |
1da177e4 LT |
176 | }; |
177 | ||
178 | #define DEFAULT_COW { \ | |
179 | .file = NULL, \ | |
dc764e50 JD |
180 | .fd = -1, \ |
181 | .bitmap = NULL, \ | |
1da177e4 | 182 | .bitmap_offset = 0, \ |
dc764e50 | 183 | .data_offset = 0, \ |
1da177e4 LT |
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, \ | |
dc764e50 | 193 | .no_cow = 0, \ |
6c29256c | 194 | .shared = 0, \ |
dc764e50 | 195 | .cow = DEFAULT_COW, \ |
62f96cb0 | 196 | .lock = SPIN_LOCK_UNLOCKED, \ |
a0044bdf JD |
197 | .request = NULL, \ |
198 | .start_sg = 0, \ | |
199 | .end_sg = 0, \ | |
1da177e4 LT |
200 | } |
201 | ||
b8831a1d | 202 | /* Protected by ubd_lock */ |
7d314e34 | 203 | struct ubd ubd_devs[MAX_DEV] = { [ 0 ... MAX_DEV - 1 ] = DEFAULT_UBD }; |
1da177e4 | 204 | |
1da177e4 LT |
205 | /* Only changed by fake_ide_setup which is a setup */ |
206 | static int fake_ide = 0; | |
207 | static struct proc_dir_entry *proc_ide_root = NULL; | |
208 | static struct proc_dir_entry *proc_ide = NULL; | |
209 | ||
210 | static void make_proc_ide(void) | |
211 | { | |
212 | proc_ide_root = proc_mkdir("ide", NULL); | |
213 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
214 | } | |
215 | ||
216 | static int proc_ide_read_media(char *page, char **start, off_t off, int count, | |
217 | int *eof, void *data) | |
218 | { | |
219 | int len; | |
220 | ||
221 | strcpy(page, "disk\n"); | |
222 | len = strlen("disk\n"); | |
223 | len -= off; | |
224 | if (len < count){ | |
225 | *eof = 1; | |
226 | if (len <= 0) return 0; | |
227 | } | |
228 | else len = count; | |
229 | *start = page + off; | |
230 | return len; | |
231 | } | |
232 | ||
c0a9290e | 233 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
234 | { |
235 | struct proc_dir_entry *dir, *ent; | |
236 | char name[64]; | |
237 | ||
238 | if(proc_ide_root == NULL) make_proc_ide(); | |
239 | ||
240 | dir = proc_mkdir(dev_name, proc_ide); | |
241 | if(!dir) return; | |
242 | ||
243 | ent = create_proc_entry("media", S_IFREG|S_IRUGO, dir); | |
244 | if(!ent) return; | |
1da177e4 LT |
245 | ent->data = NULL; |
246 | ent->read_proc = proc_ide_read_media; | |
247 | ent->write_proc = NULL; | |
c0a9290e | 248 | snprintf(name, sizeof(name), "ide0/%s", dev_name); |
1da177e4 LT |
249 | proc_symlink(dev_name, proc_ide_root, name); |
250 | } | |
251 | ||
252 | static int fake_ide_setup(char *str) | |
253 | { | |
254 | fake_ide = 1; | |
dc764e50 | 255 | return 1; |
1da177e4 LT |
256 | } |
257 | ||
258 | __setup("fake_ide", fake_ide_setup); | |
259 | ||
260 | __uml_help(fake_ide_setup, | |
261 | "fake_ide\n" | |
262 | " Create ide0 entries that map onto ubd devices.\n\n" | |
263 | ); | |
264 | ||
265 | static int parse_unit(char **ptr) | |
266 | { | |
267 | char *str = *ptr, *end; | |
268 | int n = -1; | |
269 | ||
270 | if(isdigit(*str)) { | |
271 | n = simple_strtoul(str, &end, 0); | |
272 | if(end == str) | |
dc764e50 | 273 | return -1; |
1da177e4 LT |
274 | *ptr = end; |
275 | } | |
97d88ac8 | 276 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
277 | n = *str - 'a'; |
278 | str++; | |
279 | *ptr = str; | |
280 | } | |
dc764e50 | 281 | return n; |
1da177e4 LT |
282 | } |
283 | ||
d8d7c28e PBG |
284 | /* If *index_out == -1 at exit, the passed option was a general one; |
285 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
286 | * should not be freed on exit. | |
287 | */ | |
f28169d2 | 288 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 289 | { |
7d314e34 | 290 | struct ubd *ubd_dev; |
1da177e4 LT |
291 | struct openflags flags = global_openflags; |
292 | char *backing_file; | |
b8831a1d | 293 | int n, err = 0, i; |
1da177e4 LT |
294 | |
295 | if(index_out) *index_out = -1; | |
296 | n = *str; | |
297 | if(n == '='){ | |
298 | char *end; | |
299 | int major; | |
300 | ||
301 | str++; | |
1da177e4 LT |
302 | if(!strcmp(str, "sync")){ |
303 | global_openflags = of_sync(global_openflags); | |
b8831a1d | 304 | goto out1; |
1da177e4 | 305 | } |
b8831a1d JD |
306 | |
307 | err = -EINVAL; | |
1da177e4 LT |
308 | major = simple_strtoul(str, &end, 0); |
309 | if((*end != '\0') || (end == str)){ | |
f28169d2 | 310 | *error_out = "Didn't parse major number"; |
b8831a1d | 311 | goto out1; |
1da177e4 LT |
312 | } |
313 | ||
f28169d2 JD |
314 | mutex_lock(&ubd_lock); |
315 | if(fake_major != MAJOR_NR){ | |
316 | *error_out = "Can't assign a fake major twice"; | |
317 | goto out1; | |
318 | } | |
6c29256c | 319 | |
f28169d2 | 320 | fake_major = major; |
1da177e4 LT |
321 | |
322 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
323 | major); | |
f28169d2 JD |
324 | err = 0; |
325 | out1: | |
326 | mutex_unlock(&ubd_lock); | |
327 | return err; | |
1da177e4 LT |
328 | } |
329 | ||
330 | n = parse_unit(&str); | |
331 | if(n < 0){ | |
f28169d2 JD |
332 | *error_out = "Couldn't parse device number"; |
333 | return -EINVAL; | |
1da177e4 LT |
334 | } |
335 | if(n >= MAX_DEV){ | |
f28169d2 JD |
336 | *error_out = "Device number out of range"; |
337 | return 1; | |
1da177e4 LT |
338 | } |
339 | ||
f28169d2 | 340 | err = -EBUSY; |
d7fb2c38 | 341 | mutex_lock(&ubd_lock); |
1da177e4 | 342 | |
7d314e34 PBG |
343 | ubd_dev = &ubd_devs[n]; |
344 | if(ubd_dev->file != NULL){ | |
f28169d2 | 345 | *error_out = "Device is already configured"; |
1da177e4 LT |
346 | goto out; |
347 | } | |
348 | ||
349 | if (index_out) | |
350 | *index_out = n; | |
351 | ||
f28169d2 | 352 | err = -EINVAL; |
6c29256c | 353 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
354 | switch (*str) { |
355 | case 'r': | |
356 | flags.w = 0; | |
357 | break; | |
358 | case 's': | |
359 | flags.s = 1; | |
360 | break; | |
361 | case 'd': | |
7d314e34 | 362 | ubd_dev->no_cow = 1; |
1da177e4 | 363 | break; |
6c29256c | 364 | case 'c': |
7d314e34 | 365 | ubd_dev->shared = 1; |
6c29256c | 366 | break; |
1da177e4 LT |
367 | case '=': |
368 | str++; | |
369 | goto break_loop; | |
370 | default: | |
f28169d2 JD |
371 | *error_out = "Expected '=' or flag letter " |
372 | "(r, s, c, or d)"; | |
1da177e4 LT |
373 | goto out; |
374 | } | |
375 | str++; | |
376 | } | |
377 | ||
f28169d2 JD |
378 | if (*str == '=') |
379 | *error_out = "Too many flags specified"; | |
380 | else | |
381 | *error_out = "Missing '='"; | |
1da177e4 LT |
382 | goto out; |
383 | ||
384 | break_loop: | |
1da177e4 LT |
385 | backing_file = strchr(str, ','); |
386 | ||
f28169d2 | 387 | if (backing_file == NULL) |
1da177e4 | 388 | backing_file = strchr(str, ':'); |
1da177e4 | 389 | |
f28169d2 JD |
390 | if(backing_file != NULL){ |
391 | if(ubd_dev->no_cow){ | |
392 | *error_out = "Can't specify both 'd' and a cow file"; | |
393 | goto out; | |
394 | } | |
1da177e4 LT |
395 | else { |
396 | *backing_file = '\0'; | |
397 | backing_file++; | |
398 | } | |
399 | } | |
f28169d2 | 400 | err = 0; |
7d314e34 PBG |
401 | ubd_dev->file = str; |
402 | ubd_dev->cow.file = backing_file; | |
403 | ubd_dev->boot_openflags = flags; | |
1da177e4 | 404 | out: |
d7fb2c38 | 405 | mutex_unlock(&ubd_lock); |
f28169d2 | 406 | return err; |
1da177e4 LT |
407 | } |
408 | ||
409 | static int ubd_setup(char *str) | |
410 | { | |
f28169d2 JD |
411 | char *error; |
412 | int err; | |
413 | ||
414 | err = ubd_setup_common(str, NULL, &error); | |
415 | if(err) | |
416 | printk(KERN_ERR "Failed to initialize device with \"%s\" : " | |
417 | "%s\n", str, error); | |
418 | return 1; | |
1da177e4 LT |
419 | } |
420 | ||
421 | __setup("ubd", ubd_setup); | |
422 | __uml_help(ubd_setup, | |
423 | "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" | |
424 | " This is used to associate a device with a file in the underlying\n" | |
425 | " filesystem. When specifying two filenames, the first one is the\n" | |
426 | " COW name and the second is the backing file name. As separator you can\n" | |
427 | " use either a ':' or a ',': the first one allows writing things like;\n" | |
428 | " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" | |
429 | " while with a ',' the shell would not expand the 2nd '~'.\n" | |
f28169d2 | 430 | " When using only one filename, UML will detect whether to treat it like\n" |
1da177e4 LT |
431 | " a COW file or a backing file. To override this detection, add the 'd'\n" |
432 | " flag:\n" | |
433 | " ubd0d=BackingFile\n" | |
434 | " Usually, there is a filesystem in the file, but \n" | |
435 | " that's not required. Swap devices containing swap files can be\n" | |
436 | " specified like this. Also, a file which doesn't contain a\n" | |
437 | " filesystem can have its contents read in the virtual \n" | |
438 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
439 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
440 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
20ede453 JD |
441 | " an 's' will cause data to be written to disk on the host immediately.\n" |
442 | " 'c' will cause the device to be treated as being shared between multiple\n" | |
443 | " UMLs and file locking will be turned off - this is appropriate for a\n" | |
444 | " cluster filesystem and inappropriate at almost all other times.\n\n" | |
1da177e4 LT |
445 | ); |
446 | ||
8299ca5c | 447 | static int udb_setup(char *str) |
1da177e4 LT |
448 | { |
449 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
450 | "udb TYPO\n", str); | |
dc764e50 | 451 | return 1; |
1da177e4 LT |
452 | } |
453 | ||
454 | __setup("udb", udb_setup); | |
455 | __uml_help(udb_setup, | |
456 | "udb\n" | |
0894e27e JD |
457 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
458 | " to impossible to catch visually unless you specifically look for\n" | |
459 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
460 | " in the boot output.\n\n" |
461 | ); | |
462 | ||
165125e1 | 463 | static void do_ubd_request(struct request_queue * q); |
91acb21f JD |
464 | |
465 | /* Only changed by ubd_init, which is an initcall. */ | |
466 | int thread_fd = -1; | |
1da177e4 | 467 | |
4898b53a | 468 | static void ubd_end_request(struct request *req, int bytes, int error) |
1da177e4 | 469 | { |
4898b53a | 470 | blk_end_request(req, error, bytes); |
1da177e4 LT |
471 | } |
472 | ||
33f775ee PBG |
473 | /* Callable only from interrupt context - otherwise you need to do |
474 | * spin_lock_irq()/spin_lock_irqsave() */ | |
a0044bdf | 475 | static inline void ubd_finish(struct request *req, int bytes) |
1da177e4 | 476 | { |
a0044bdf | 477 | if(bytes < 0){ |
4898b53a | 478 | ubd_end_request(req, 0, -EIO); |
a0044bdf JD |
479 | return; |
480 | } | |
4898b53a | 481 | ubd_end_request(req, bytes, 0); |
1da177e4 LT |
482 | } |
483 | ||
a0044bdf JD |
484 | static LIST_HEAD(restart); |
485 | ||
2fe30a34 | 486 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 487 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 488 | static void ubd_handler(void) |
1da177e4 | 489 | { |
2adcec21 | 490 | struct io_thread_req *req; |
62f96cb0 | 491 | struct request *rq; |
a0044bdf JD |
492 | struct ubd *ubd; |
493 | struct list_head *list, *next_ele; | |
494 | unsigned long flags; | |
91acb21f JD |
495 | int n; |
496 | ||
a0044bdf | 497 | while(1){ |
a6ea4cce JD |
498 | n = os_read_file(thread_fd, &req, |
499 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
500 | if(n != sizeof(req)){ |
501 | if(n == -EAGAIN) | |
502 | break; | |
503 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
504 | "err = %d\n", -n); | |
505 | return; | |
506 | } | |
62f96cb0 | 507 | |
2adcec21 JD |
508 | rq = req->req; |
509 | rq->nr_sectors -= req->length >> 9; | |
a0044bdf JD |
510 | if(rq->nr_sectors == 0) |
511 | ubd_finish(rq, rq->hard_nr_sectors << 9); | |
2adcec21 | 512 | kfree(req); |
a0044bdf | 513 | } |
62f96cb0 | 514 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
515 | |
516 | list_for_each_safe(list, next_ele, &restart){ | |
517 | ubd = container_of(list, struct ubd, restart); | |
518 | list_del_init(&ubd->restart); | |
519 | spin_lock_irqsave(&ubd->lock, flags); | |
520 | do_ubd_request(ubd->queue); | |
521 | spin_unlock_irqrestore(&ubd->lock, flags); | |
522 | } | |
1da177e4 LT |
523 | } |
524 | ||
7bea96fd | 525 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 526 | { |
91acb21f | 527 | ubd_handler(); |
dc764e50 | 528 | return IRQ_HANDLED; |
91acb21f | 529 | } |
09ace81c | 530 | |
91acb21f JD |
531 | /* Only changed by ubd_init, which is an initcall. */ |
532 | static int io_pid = -1; | |
09ace81c | 533 | |
91acb21f JD |
534 | void kill_io_thread(void) |
535 | { | |
6c29256c | 536 | if(io_pid != -1) |
91acb21f | 537 | os_kill_process(io_pid, 1); |
09ace81c | 538 | } |
1da177e4 | 539 | |
91acb21f JD |
540 | __uml_exitcall(kill_io_thread); |
541 | ||
d8d7c28e | 542 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
543 | { |
544 | char *file; | |
545 | ||
7d314e34 | 546 | file = ubd_dev->cow.file ? ubd_dev->cow.file : ubd_dev->file; |
dc764e50 | 547 | return os_file_size(file, size_out); |
1da177e4 LT |
548 | } |
549 | ||
5f75a4f8 | 550 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 551 | { |
7d314e34 PBG |
552 | os_close_file(ubd_dev->fd); |
553 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
554 | return; |
555 | ||
7d314e34 PBG |
556 | os_close_file(ubd_dev->cow.fd); |
557 | vfree(ubd_dev->cow.bitmap); | |
558 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
559 | } |
560 | ||
7d314e34 | 561 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
562 | { |
563 | struct openflags flags; | |
564 | char **back_ptr; | |
565 | int err, create_cow, *create_ptr; | |
0bf16bff | 566 | int fd; |
1da177e4 | 567 | |
7d314e34 | 568 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 569 | create_cow = 0; |
7d314e34 PBG |
570 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
571 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
572 | |
573 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
574 | back_ptr, &ubd_dev->cow.bitmap_offset, |
575 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 576 | create_ptr); |
1da177e4 | 577 | |
0bf16bff PBG |
578 | if((fd == -ENOENT) && create_cow){ |
579 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
580 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
581 | &ubd_dev->cow.bitmap_offset, | |
582 | &ubd_dev->cow.bitmap_len, | |
583 | &ubd_dev->cow.data_offset); | |
0bf16bff | 584 | if(fd >= 0){ |
1da177e4 | 585 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 586 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
587 | } |
588 | } | |
589 | ||
0bf16bff | 590 | if(fd < 0){ |
7d314e34 | 591 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
592 | -fd); |
593 | return fd; | |
1da177e4 | 594 | } |
0bf16bff | 595 | ubd_dev->fd = fd; |
1da177e4 | 596 | |
7d314e34 | 597 | if(ubd_dev->cow.file != NULL){ |
f4768ffd JD |
598 | blk_queue_max_sectors(ubd_dev->queue, 8 * sizeof(long)); |
599 | ||
1da177e4 | 600 | err = -ENOMEM; |
da2486ba | 601 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 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 | 620 | } |
dc764e50 | 621 | return 0; |
1da177e4 | 622 | error: |
7d314e34 | 623 | os_close_file(ubd_dev->fd); |
dc764e50 | 624 | return err; |
1da177e4 LT |
625 | } |
626 | ||
2e3f5251 JD |
627 | static void ubd_device_release(struct device *dev) |
628 | { | |
629 | struct ubd *ubd_dev = dev->driver_data; | |
630 | ||
631 | blk_cleanup_queue(ubd_dev->queue); | |
632 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
633 | } | |
634 | ||
5f75a4f8 | 635 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 636 | struct gendisk **disk_out) |
1da177e4 LT |
637 | { |
638 | struct gendisk *disk; | |
1da177e4 LT |
639 | |
640 | disk = alloc_disk(1 << UBD_SHIFT); | |
641 | if(disk == NULL) | |
dc764e50 | 642 | return -ENOMEM; |
1da177e4 LT |
643 | |
644 | disk->major = major; | |
645 | disk->first_minor = unit << UBD_SHIFT; | |
646 | disk->fops = &ubd_blops; | |
647 | set_capacity(disk, size / 512); | |
ce7b0f46 | 648 | if(major == MAJOR_NR) |
1da177e4 | 649 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 650 | else |
1da177e4 | 651 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
652 | |
653 | /* sysfs register (not for ide fake devices) */ | |
654 | if (major == MAJOR_NR) { | |
7d314e34 PBG |
655 | ubd_devs[unit].pdev.id = unit; |
656 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 JD |
657 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
658 | ubd_devs[unit].pdev.dev.driver_data = &ubd_devs[unit]; | |
7d314e34 PBG |
659 | platform_device_register(&ubd_devs[unit].pdev); |
660 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
661 | } |
662 | ||
7d314e34 | 663 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 664 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
665 | add_disk(disk); |
666 | ||
667 | *disk_out = disk; | |
668 | return 0; | |
669 | } | |
670 | ||
671 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
672 | ||
f28169d2 | 673 | static int ubd_add(int n, char **error_out) |
1da177e4 | 674 | { |
7d314e34 | 675 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 676 | int err = 0; |
1da177e4 | 677 | |
7d314e34 | 678 | if(ubd_dev->file == NULL) |
ec7cf783 | 679 | goto out; |
1da177e4 | 680 | |
7d314e34 | 681 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
682 | if(err < 0){ |
683 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 684 | goto out; |
f28169d2 | 685 | } |
1da177e4 | 686 | |
7d314e34 | 687 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 688 | |
a0044bdf | 689 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 690 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 691 | |
62f96cb0 JD |
692 | err = -ENOMEM; |
693 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
694 | if (ubd_dev->queue == NULL) { | |
695 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 696 | goto out; |
62f96cb0 JD |
697 | } |
698 | ubd_dev->queue->queuedata = ubd_dev; | |
699 | ||
a0044bdf | 700 | blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG); |
62f96cb0 JD |
701 | err = ubd_disk_register(MAJOR_NR, ubd_dev->size, n, &ubd_gendisk[n]); |
702 | if(err){ | |
703 | *error_out = "Failed to register device"; | |
704 | goto out_cleanup; | |
705 | } | |
6c29256c | 706 | |
1da177e4 | 707 | if(fake_major != MAJOR_NR) |
5f75a4f8 | 708 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 709 | &fake_gendisk[n]); |
1da177e4 | 710 | |
83380cc1 JD |
711 | /* |
712 | * Perhaps this should also be under the "if (fake_major)" above | |
713 | * using the fake_disk->disk_name | |
714 | */ | |
1da177e4 LT |
715 | if (fake_ide) |
716 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
717 | ||
ec7cf783 | 718 | err = 0; |
ec7cf783 JD |
719 | out: |
720 | return err; | |
62f96cb0 JD |
721 | |
722 | out_cleanup: | |
723 | blk_cleanup_queue(ubd_dev->queue); | |
724 | goto out; | |
1da177e4 LT |
725 | } |
726 | ||
f28169d2 | 727 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 728 | { |
e7f6552f | 729 | int n, ret; |
1da177e4 | 730 | |
f28169d2 JD |
731 | /* This string is possibly broken up and stored, so it's only |
732 | * freed if ubd_setup_common fails, or if only general options | |
733 | * were set. | |
734 | */ | |
970d6e3a | 735 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 736 | if (str == NULL) { |
f28169d2 JD |
737 | *error_out = "Failed to allocate memory"; |
738 | return -ENOMEM; | |
1da177e4 | 739 | } |
f28169d2 JD |
740 | |
741 | ret = ubd_setup_common(str, &n, error_out); | |
742 | if (ret) | |
e7f6552f | 743 | goto err_free; |
f28169d2 | 744 | |
e7f6552f PBG |
745 | if (n == -1) { |
746 | ret = 0; | |
d8d7c28e | 747 | goto err_free; |
1da177e4 | 748 | } |
1da177e4 | 749 | |
dc764e50 | 750 | mutex_lock(&ubd_lock); |
f28169d2 | 751 | ret = ubd_add(n, error_out); |
e7f6552f | 752 | if (ret) |
7d314e34 | 753 | ubd_devs[n].file = NULL; |
dc764e50 | 754 | mutex_unlock(&ubd_lock); |
1da177e4 | 755 | |
e7f6552f | 756 | out: |
dc764e50 | 757 | return ret; |
e7f6552f PBG |
758 | |
759 | err_free: | |
760 | kfree(str); | |
761 | goto out; | |
1da177e4 LT |
762 | } |
763 | ||
764 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
765 | { | |
7d314e34 | 766 | struct ubd *ubd_dev; |
1da177e4 LT |
767 | int n, len = 0; |
768 | ||
769 | n = parse_unit(&name); | |
770 | if((n >= MAX_DEV) || (n < 0)){ | |
771 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 772 | return -1; |
1da177e4 LT |
773 | } |
774 | ||
7d314e34 | 775 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 776 | mutex_lock(&ubd_lock); |
1da177e4 | 777 | |
7d314e34 | 778 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
779 | CONFIG_CHUNK(str, size, len, "", 1); |
780 | goto out; | |
781 | } | |
782 | ||
7d314e34 | 783 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 784 | |
7d314e34 | 785 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 786 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 787 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
788 | } |
789 | else CONFIG_CHUNK(str, size, len, "", 1); | |
790 | ||
791 | out: | |
d7fb2c38 | 792 | mutex_unlock(&ubd_lock); |
dc764e50 | 793 | return len; |
1da177e4 LT |
794 | } |
795 | ||
29d56cfe JD |
796 | static int ubd_id(char **str, int *start_out, int *end_out) |
797 | { | |
dc764e50 | 798 | int n; |
29d56cfe JD |
799 | |
800 | n = parse_unit(str); | |
dc764e50 JD |
801 | *start_out = 0; |
802 | *end_out = MAX_DEV - 1; | |
803 | return n; | |
29d56cfe JD |
804 | } |
805 | ||
f28169d2 | 806 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 807 | { |
2e3f5251 | 808 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 809 | struct ubd *ubd_dev; |
29d56cfe | 810 | int err = -ENODEV; |
1da177e4 | 811 | |
d7fb2c38 | 812 | mutex_lock(&ubd_lock); |
1da177e4 | 813 | |
7d314e34 | 814 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 815 | |
7d314e34 | 816 | if(ubd_dev->file == NULL) |
29d56cfe | 817 | goto out; |
1da177e4 | 818 | |
29d56cfe JD |
819 | /* you cannot remove a open disk */ |
820 | err = -EBUSY; | |
7d314e34 | 821 | if(ubd_dev->count > 0) |
1da177e4 LT |
822 | goto out; |
823 | ||
dc764e50 | 824 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
825 | if(disk != NULL){ |
826 | del_gendisk(disk); | |
827 | put_disk(disk); | |
828 | } | |
1da177e4 LT |
829 | |
830 | if(fake_gendisk[n] != NULL){ | |
831 | del_gendisk(fake_gendisk[n]); | |
832 | put_disk(fake_gendisk[n]); | |
833 | fake_gendisk[n] = NULL; | |
834 | } | |
835 | ||
1da177e4 | 836 | err = 0; |
2e3f5251 | 837 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 838 | out: |
d7fb2c38 | 839 | mutex_unlock(&ubd_lock); |
29d56cfe | 840 | return err; |
1da177e4 LT |
841 | } |
842 | ||
f28169d2 | 843 | /* All these are called by mconsole in process context and without |
b8831a1d | 844 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 845 | */ |
1da177e4 | 846 | static struct mc_device ubd_mc = { |
84f48d4f | 847 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
848 | .name = "ubd", |
849 | .config = ubd_config, | |
dc764e50 | 850 | .get_config = ubd_get_config, |
29d56cfe | 851 | .id = ubd_id, |
1da177e4 LT |
852 | .remove = ubd_remove, |
853 | }; | |
854 | ||
d8d7c28e | 855 | static int __init ubd_mc_init(void) |
1da177e4 LT |
856 | { |
857 | mconsole_register_dev(&ubd_mc); | |
858 | return 0; | |
859 | } | |
860 | ||
861 | __initcall(ubd_mc_init); | |
862 | ||
d8d7c28e PBG |
863 | static int __init ubd0_init(void) |
864 | { | |
865 | struct ubd *ubd_dev = &ubd_devs[0]; | |
866 | ||
b8831a1d | 867 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
868 | if(ubd_dev->file == NULL) |
869 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
870 | mutex_unlock(&ubd_lock); |
871 | ||
dc764e50 | 872 | return 0; |
d8d7c28e PBG |
873 | } |
874 | ||
875 | __initcall(ubd0_init); | |
876 | ||
b8831a1d | 877 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
878 | static struct platform_driver ubd_driver = { |
879 | .driver = { | |
880 | .name = DRIVER_NAME, | |
881 | }, | |
1da177e4 LT |
882 | }; |
883 | ||
d8d7c28e | 884 | static int __init ubd_init(void) |
1da177e4 | 885 | { |
f28169d2 JD |
886 | char *error; |
887 | int i, err; | |
1da177e4 | 888 | |
1da177e4 LT |
889 | if (register_blkdev(MAJOR_NR, "ubd")) |
890 | return -1; | |
891 | ||
1da177e4 LT |
892 | if (fake_major != MAJOR_NR) { |
893 | char name[sizeof("ubd_nnn\0")]; | |
894 | ||
895 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
896 | if (register_blkdev(fake_major, "ubd")) |
897 | return -1; | |
898 | } | |
3ae5eaec | 899 | platform_driver_register(&ubd_driver); |
dc764e50 | 900 | mutex_lock(&ubd_lock); |
f28169d2 JD |
901 | for (i = 0; i < MAX_DEV; i++){ |
902 | err = ubd_add(i, &error); | |
903 | if(err) | |
904 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
905 | "%s\n", i, error); | |
906 | } | |
dc764e50 | 907 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
908 | return 0; |
909 | } | |
910 | ||
911 | late_initcall(ubd_init); | |
912 | ||
d8d7c28e | 913 | static int __init ubd_driver_init(void){ |
91acb21f JD |
914 | unsigned long stack; |
915 | int err; | |
916 | ||
917 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
918 | if(global_openflags.s){ | |
919 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
920 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
921 | * enough. So use anyway the io thread. */ | |
922 | } | |
923 | stack = alloc_stack(0, 0); | |
6c29256c | 924 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
925 | &thread_fd); |
926 | if(io_pid < 0){ | |
6c29256c | 927 | printk(KERN_ERR |
91acb21f JD |
928 | "ubd : Failed to start I/O thread (errno = %d) - " |
929 | "falling back to synchronous I/O\n", -io_pid); | |
930 | io_pid = -1; | |
dc764e50 | 931 | return 0; |
91acb21f | 932 | } |
6c29256c | 933 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
7d314e34 | 934 | IRQF_DISABLED, "ubd", ubd_devs); |
91acb21f JD |
935 | if(err != 0) |
936 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 937 | return 0; |
91acb21f JD |
938 | } |
939 | ||
940 | device_initcall(ubd_driver_init); | |
941 | ||
1da177e4 LT |
942 | static int ubd_open(struct inode *inode, struct file *filp) |
943 | { | |
944 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 945 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
946 | int err = 0; |
947 | ||
7d314e34 PBG |
948 | if(ubd_dev->count == 0){ |
949 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
950 | if(err){ |
951 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 952 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
953 | goto out; |
954 | } | |
955 | } | |
7d314e34 PBG |
956 | ubd_dev->count++; |
957 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
958 | |
959 | /* This should no more be needed. And it didn't work anyway to exclude | |
960 | * read-write remounting of filesystems.*/ | |
7d314e34 | 961 | /*if((filp->f_mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 962 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 963 | err = -EROFS; |
2c49be99 | 964 | }*/ |
1da177e4 | 965 | out: |
dc764e50 | 966 | return err; |
1da177e4 LT |
967 | } |
968 | ||
969 | static int ubd_release(struct inode * inode, struct file * file) | |
970 | { | |
971 | struct gendisk *disk = inode->i_bdev->bd_disk; | |
7d314e34 | 972 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 973 | |
7d314e34 | 974 | if(--ubd_dev->count == 0) |
5f75a4f8 | 975 | ubd_close_dev(ubd_dev); |
dc764e50 | 976 | return 0; |
1da177e4 LT |
977 | } |
978 | ||
91acb21f JD |
979 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
980 | __u64 *cow_offset, unsigned long *bitmap, | |
981 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
982 | __u64 bitmap_len) | |
1da177e4 | 983 | { |
91acb21f JD |
984 | __u64 sector = io_offset >> 9; |
985 | int i, update_bitmap = 0; | |
986 | ||
987 | for(i = 0; i < length >> 9; i++){ | |
988 | if(cow_mask != NULL) | |
989 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
990 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
991 | continue; | |
1da177e4 | 992 | |
91acb21f JD |
993 | update_bitmap = 1; |
994 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
995 | } | |
996 | ||
997 | if(!update_bitmap) | |
998 | return; | |
1da177e4 | 999 | |
91acb21f | 1000 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1001 | |
91acb21f JD |
1002 | /* This takes care of the case where we're exactly at the end of the |
1003 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1004 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1005 | * for the original diagnosis. | |
1006 | */ | |
1007 | if(*cow_offset == ((bitmap_len + sizeof(unsigned long) - 1) / | |
1008 | sizeof(unsigned long) - 1)) | |
1009 | (*cow_offset)--; | |
1010 | ||
1011 | bitmap_words[0] = bitmap[*cow_offset]; | |
1012 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1013 | ||
1014 | *cow_offset *= sizeof(unsigned long); | |
1015 | *cow_offset += bitmap_offset; | |
1016 | } | |
1017 | ||
1018 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1019 | __u64 bitmap_offset, __u64 bitmap_len) | |
1020 | { | |
1021 | __u64 sector = req->offset >> 9; | |
1022 | int i; | |
1023 | ||
1024 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1025 | panic("Operation too long"); | |
1026 | ||
1027 | if(req->op == UBD_READ) { | |
1028 | for(i = 0; i < req->length >> 9; i++){ | |
1029 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1030 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1031 | &req->sector_mask); |
dc764e50 | 1032 | } |
91acb21f JD |
1033 | } |
1034 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1035 | &req->cow_offset, bitmap, bitmap_offset, | |
1036 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1037 | } |
1038 | ||
62f96cb0 | 1039 | /* Called with dev->lock held */ |
a0044bdf JD |
1040 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1041 | unsigned long long offset, int page_offset, | |
1042 | int len, struct page *page) | |
1da177e4 LT |
1043 | { |
1044 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1045 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1046 | |
62f96cb0 | 1047 | io_req->req = req; |
a0044bdf JD |
1048 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1049 | ubd_dev->fd; | |
7d314e34 | 1050 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1051 | io_req->cow_offset = -1; |
1da177e4 LT |
1052 | io_req->offset = offset; |
1053 | io_req->length = len; | |
1054 | io_req->error = 0; | |
91acb21f JD |
1055 | io_req->sector_mask = 0; |
1056 | ||
1057 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1058 | io_req->offsets[0] = 0; |
7d314e34 | 1059 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1060 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1061 | io_req->sectorsize = 1 << 9; |
1062 | ||
7d314e34 | 1063 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1064 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1065 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1066 | |
1da177e4 LT |
1067 | } |
1068 | ||
62f96cb0 | 1069 | /* Called with dev->lock held */ |
165125e1 | 1070 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1071 | { |
2adcec21 | 1072 | struct io_thread_req *io_req; |
1da177e4 | 1073 | struct request *req; |
0a6d3a2a | 1074 | int n, last_sectors; |
a0044bdf JD |
1075 | |
1076 | while(1){ | |
2a9529a0 | 1077 | struct ubd *dev = q->queuedata; |
a0044bdf JD |
1078 | if(dev->end_sg == 0){ |
1079 | struct request *req = elv_next_request(q); | |
1080 | if(req == NULL) | |
1081 | return; | |
1082 | ||
1083 | dev->request = req; | |
1084 | blkdev_dequeue_request(req); | |
1085 | dev->start_sg = 0; | |
1086 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1087 | } | |
1088 | ||
1089 | req = dev->request; | |
0a6d3a2a | 1090 | last_sectors = 0; |
a0044bdf JD |
1091 | while(dev->start_sg < dev->end_sg){ |
1092 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1093 | ||
0a6d3a2a | 1094 | req->sector += last_sectors; |
2adcec21 | 1095 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1096 | GFP_ATOMIC); |
2adcec21 JD |
1097 | if(io_req == NULL){ |
1098 | if(list_empty(&dev->restart)) | |
1099 | list_add(&dev->restart, &restart); | |
1100 | return; | |
1101 | } | |
1102 | prepare_request(req, io_req, | |
a0044bdf | 1103 | (unsigned long long) req->sector << 9, |
45711f1a | 1104 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1105 | |
0a6d3a2a | 1106 | last_sectors = sg->length >> 9; |
a6ea4cce JD |
1107 | n = os_write_file(thread_fd, &io_req, |
1108 | sizeof(struct io_thread_req *)); | |
2adcec21 | 1109 | if(n != sizeof(struct io_thread_req *)){ |
a0044bdf JD |
1110 | if(n != -EAGAIN) |
1111 | printk("write to io thread failed, " | |
1112 | "errno = %d\n", -n); | |
1113 | else if(list_empty(&dev->restart)) | |
1114 | list_add(&dev->restart, &restart); | |
12429bf9 | 1115 | kfree(io_req); |
a0044bdf JD |
1116 | return; |
1117 | } | |
1118 | ||
a0044bdf | 1119 | dev->start_sg++; |
1da177e4 | 1120 | } |
a0044bdf JD |
1121 | dev->end_sg = 0; |
1122 | dev->request = NULL; | |
1da177e4 LT |
1123 | } |
1124 | } | |
1125 | ||
a885c8c4 CH |
1126 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1127 | { | |
7d314e34 | 1128 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1129 | |
1130 | geo->heads = 128; | |
1131 | geo->sectors = 32; | |
7d314e34 | 1132 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1133 | return 0; |
1134 | } | |
1135 | ||
1da177e4 LT |
1136 | static int ubd_ioctl(struct inode * inode, struct file * file, |
1137 | unsigned int cmd, unsigned long arg) | |
1138 | { | |
7d314e34 | 1139 | struct ubd *ubd_dev = inode->i_bdev->bd_disk->private_data; |
1da177e4 LT |
1140 | struct hd_driveid ubd_id = { |
1141 | .cyls = 0, | |
1142 | .heads = 128, | |
1143 | .sectors = 32, | |
1144 | }; | |
1145 | ||
1146 | switch (cmd) { | |
1da177e4 | 1147 | struct cdrom_volctrl volume; |
1da177e4 | 1148 | case HDIO_GET_IDENTITY: |
7d314e34 | 1149 | ubd_id.cyls = ubd_dev->size / (128 * 32 * 512); |
1da177e4 LT |
1150 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1151 | sizeof(ubd_id))) | |
dc764e50 JD |
1152 | return -EFAULT; |
1153 | return 0; | |
b8831a1d | 1154 | |
1da177e4 LT |
1155 | case CDROMVOLREAD: |
1156 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1157 | return -EFAULT; |
1da177e4 LT |
1158 | volume.channel0 = 255; |
1159 | volume.channel1 = 255; | |
1160 | volume.channel2 = 255; | |
1161 | volume.channel3 = 255; | |
1162 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1163 | return -EFAULT; |
1164 | return 0; | |
1da177e4 | 1165 | } |
dc764e50 | 1166 | return -EINVAL; |
1da177e4 LT |
1167 | } |
1168 | ||
4833aff7 | 1169 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) |
1da177e4 LT |
1170 | { |
1171 | struct uml_stat buf1, buf2; | |
1172 | int err; | |
1173 | ||
4833aff7 PBG |
1174 | if(from_cmdline == NULL) |
1175 | return 0; | |
1176 | if(!strcmp(from_cmdline, from_cow)) | |
1177 | return 0; | |
1da177e4 LT |
1178 | |
1179 | err = os_stat_file(from_cmdline, &buf1); | |
1180 | if(err < 0){ | |
1181 | printk("Couldn't stat '%s', err = %d\n", from_cmdline, -err); | |
4833aff7 | 1182 | return 0; |
1da177e4 LT |
1183 | } |
1184 | err = os_stat_file(from_cow, &buf2); | |
1185 | if(err < 0){ | |
1186 | printk("Couldn't stat '%s', err = %d\n", from_cow, -err); | |
4833aff7 | 1187 | return 1; |
1da177e4 LT |
1188 | } |
1189 | if((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
4833aff7 | 1190 | return 0; |
1da177e4 LT |
1191 | |
1192 | printk("Backing file mismatch - \"%s\" requested,\n" | |
1193 | "\"%s\" specified in COW header of \"%s\"\n", | |
1194 | from_cmdline, from_cow, cow); | |
4833aff7 | 1195 | return 1; |
1da177e4 LT |
1196 | } |
1197 | ||
1198 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
1199 | { | |
1200 | unsigned long modtime; | |
fe1db50c | 1201 | unsigned long long actual; |
1da177e4 LT |
1202 | int err; |
1203 | ||
1204 | err = os_file_modtime(file, &modtime); | |
1205 | if(err < 0){ | |
1206 | printk("Failed to get modification time of backing file " | |
1207 | "\"%s\", err = %d\n", file, -err); | |
dc764e50 | 1208 | return err; |
1da177e4 LT |
1209 | } |
1210 | ||
1211 | err = os_file_size(file, &actual); | |
1212 | if(err < 0){ | |
1213 | printk("Failed to get size of backing file \"%s\", " | |
1214 | "err = %d\n", file, -err); | |
dc764e50 | 1215 | return err; |
1da177e4 LT |
1216 | } |
1217 | ||
dc764e50 | 1218 | if(actual != size){ |
1da177e4 LT |
1219 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so |
1220 | * the typecast.*/ | |
1221 | printk("Size mismatch (%llu vs %llu) of COW header vs backing " | |
1222 | "file\n", (unsigned long long) size, actual); | |
dc764e50 | 1223 | return -EINVAL; |
1da177e4 LT |
1224 | } |
1225 | if(modtime != mtime){ | |
1226 | printk("mtime mismatch (%ld vs %ld) of COW header vs backing " | |
1227 | "file\n", mtime, modtime); | |
dc764e50 | 1228 | return -EINVAL; |
1da177e4 | 1229 | } |
dc764e50 | 1230 | return 0; |
1da177e4 LT |
1231 | } |
1232 | ||
1233 | int read_cow_bitmap(int fd, void *buf, int offset, int len) | |
1234 | { | |
1235 | int err; | |
1236 | ||
1237 | err = os_seek_file(fd, offset); | |
1238 | if(err < 0) | |
dc764e50 | 1239 | return err; |
1da177e4 | 1240 | |
dc764e50 | 1241 | err = os_read_file(fd, buf, len); |
1da177e4 | 1242 | if(err < 0) |
dc764e50 | 1243 | return err; |
1da177e4 | 1244 | |
dc764e50 | 1245 | return 0; |
1da177e4 LT |
1246 | } |
1247 | ||
6c29256c | 1248 | int open_ubd_file(char *file, struct openflags *openflags, int shared, |
1da177e4 LT |
1249 | char **backing_file_out, int *bitmap_offset_out, |
1250 | unsigned long *bitmap_len_out, int *data_offset_out, | |
1251 | int *create_cow_out) | |
1252 | { | |
1253 | time_t mtime; | |
1254 | unsigned long long size; | |
1255 | __u32 version, align; | |
1256 | char *backing_file; | |
4833aff7 | 1257 | int fd, err, sectorsize, asked_switch, mode = 0644; |
1da177e4 LT |
1258 | |
1259 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1260 | if (fd < 0) { |
1261 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
1da177e4 | 1262 | *create_cow_out = 1; |
dc764e50 JD |
1263 | if (!openflags->w || |
1264 | ((fd != -EROFS) && (fd != -EACCES))) | |
a374a48f | 1265 | return fd; |
1da177e4 LT |
1266 | openflags->w = 0; |
1267 | fd = os_open_file(file, *openflags, mode); | |
a374a48f PBG |
1268 | if (fd < 0) |
1269 | return fd; | |
dc764e50 | 1270 | } |
1da177e4 | 1271 | |
6c29256c JD |
1272 | if(shared) |
1273 | printk("Not locking \"%s\" on the host\n", file); | |
1274 | else { | |
1275 | err = os_lock_file(fd, openflags->w); | |
1276 | if(err < 0){ | |
1277 | printk("Failed to lock '%s', err = %d\n", file, -err); | |
1278 | goto out_close; | |
1279 | } | |
1da177e4 LT |
1280 | } |
1281 | ||
d6e05edc | 1282 | /* Successful return case! */ |
a374a48f | 1283 | if(backing_file_out == NULL) |
dc764e50 | 1284 | return fd; |
1da177e4 LT |
1285 | |
1286 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
1287 | &size, §orsize, &align, bitmap_offset_out); | |
1288 | if(err && (*backing_file_out != NULL)){ | |
1289 | printk("Failed to read COW header from COW file \"%s\", " | |
1290 | "errno = %d\n", file, -err); | |
1291 | goto out_close; | |
1292 | } | |
a374a48f | 1293 | if(err) |
dc764e50 | 1294 | return fd; |
1da177e4 | 1295 | |
4833aff7 | 1296 | asked_switch = path_requires_switch(*backing_file_out, backing_file, file); |
1da177e4 | 1297 | |
4833aff7 PBG |
1298 | /* Allow switching only if no mismatch. */ |
1299 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, mtime)) { | |
1da177e4 LT |
1300 | printk("Switching backing file to '%s'\n", *backing_file_out); |
1301 | err = write_cow_header(file, fd, *backing_file_out, | |
1302 | sectorsize, align, &size); | |
a374a48f | 1303 | if (err) { |
1da177e4 | 1304 | printk("Switch failed, errno = %d\n", -err); |
4833aff7 | 1305 | goto out_close; |
1da177e4 | 1306 | } |
a374a48f | 1307 | } else { |
1da177e4 LT |
1308 | *backing_file_out = backing_file; |
1309 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
a374a48f PBG |
1310 | if (err) |
1311 | goto out_close; | |
1da177e4 LT |
1312 | } |
1313 | ||
1314 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
1315 | bitmap_len_out, data_offset_out); | |
1316 | ||
dc764e50 | 1317 | return fd; |
1da177e4 LT |
1318 | out_close: |
1319 | os_close_file(fd); | |
a374a48f | 1320 | return err; |
1da177e4 LT |
1321 | } |
1322 | ||
1323 | int create_cow_file(char *cow_file, char *backing_file, struct openflags flags, | |
1324 | int sectorsize, int alignment, int *bitmap_offset_out, | |
1325 | unsigned long *bitmap_len_out, int *data_offset_out) | |
1326 | { | |
1327 | int err, fd; | |
1328 | ||
1329 | flags.c = 1; | |
6c29256c | 1330 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); |
1da177e4 LT |
1331 | if(fd < 0){ |
1332 | err = fd; | |
1333 | printk("Open of COW file '%s' failed, errno = %d\n", cow_file, | |
1334 | -err); | |
1335 | goto out; | |
1336 | } | |
1337 | ||
1338 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
1339 | bitmap_offset_out, bitmap_len_out, | |
1340 | data_offset_out); | |
1341 | if(!err) | |
dc764e50 | 1342 | return fd; |
1da177e4 LT |
1343 | os_close_file(fd); |
1344 | out: | |
dc764e50 | 1345 | return err; |
1da177e4 LT |
1346 | } |
1347 | ||
91acb21f | 1348 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1349 | { |
91acb21f | 1350 | int n; |
1da177e4 | 1351 | |
91acb21f | 1352 | if(req->cow_offset == -1) |
dc764e50 | 1353 | return 0; |
1da177e4 | 1354 | |
91acb21f JD |
1355 | n = os_seek_file(req->fds[1], req->cow_offset); |
1356 | if(n < 0){ | |
1357 | printk("do_io - bitmap lseek failed : err = %d\n", -n); | |
dc764e50 | 1358 | return 1; |
91acb21f | 1359 | } |
1da177e4 | 1360 | |
a6ea4cce JD |
1361 | n = os_write_file(req->fds[1], &req->bitmap_words, |
1362 | sizeof(req->bitmap_words)); | |
91acb21f JD |
1363 | if(n != sizeof(req->bitmap_words)){ |
1364 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1365 | req->fds[1]); | |
dc764e50 | 1366 | return 1; |
91acb21f | 1367 | } |
1da177e4 | 1368 | |
dc764e50 | 1369 | return 0; |
91acb21f | 1370 | } |
1da177e4 | 1371 | |
91acb21f JD |
1372 | void do_io(struct io_thread_req *req) |
1373 | { | |
1374 | char *buf; | |
1375 | unsigned long len; | |
1376 | int n, nsectors, start, end, bit; | |
1377 | int err; | |
1378 | __u64 off; | |
1379 | ||
1380 | nsectors = req->length / req->sectorsize; | |
1381 | start = 0; | |
1382 | do { | |
1383 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1384 | end = start; | |
1385 | while((end < nsectors) && | |
1386 | (ubd_test_bit(end, (unsigned char *) | |
1387 | &req->sector_mask) == bit)) | |
1388 | end++; | |
1389 | ||
1390 | off = req->offset + req->offsets[bit] + | |
1391 | start * req->sectorsize; | |
1392 | len = (end - start) * req->sectorsize; | |
1393 | buf = &req->buffer[start * req->sectorsize]; | |
1394 | ||
1395 | err = os_seek_file(req->fds[bit], off); | |
1396 | if(err < 0){ | |
1397 | printk("do_io - lseek failed : err = %d\n", -err); | |
1398 | req->error = 1; | |
1399 | return; | |
1400 | } | |
1401 | if(req->op == UBD_READ){ | |
1402 | n = 0; | |
1403 | do { | |
1404 | buf = &buf[n]; | |
1405 | len -= n; | |
a6ea4cce | 1406 | n = os_read_file(req->fds[bit], buf, len); |
91acb21f JD |
1407 | if (n < 0) { |
1408 | printk("do_io - read failed, err = %d " | |
1409 | "fd = %d\n", -n, req->fds[bit]); | |
1410 | req->error = 1; | |
1411 | return; | |
1412 | } | |
1413 | } while((n < len) && (n != 0)); | |
1414 | if (n < len) memset(&buf[n], 0, len - n); | |
1415 | } else { | |
a6ea4cce | 1416 | n = os_write_file(req->fds[bit], buf, len); |
91acb21f JD |
1417 | if(n != len){ |
1418 | printk("do_io - write failed err = %d " | |
1419 | "fd = %d\n", -n, req->fds[bit]); | |
1420 | req->error = 1; | |
1421 | return; | |
1422 | } | |
1423 | } | |
1424 | ||
1425 | start = end; | |
1426 | } while(start < nsectors); | |
1da177e4 | 1427 | |
91acb21f | 1428 | req->error = update_bitmap(req); |
1da177e4 | 1429 | } |
91acb21f JD |
1430 | |
1431 | /* Changed in start_io_thread, which is serialized by being called only | |
1432 | * from ubd_init, which is an initcall. | |
1433 | */ | |
1434 | int kernel_fd = -1; | |
1435 | ||
d8d7c28e PBG |
1436 | /* Only changed by the io thread. XXX: currently unused. */ |
1437 | static int io_count = 0; | |
91acb21f JD |
1438 | |
1439 | int io_thread(void *arg) | |
1440 | { | |
2adcec21 | 1441 | struct io_thread_req *req; |
91acb21f JD |
1442 | int n; |
1443 | ||
1444 | ignore_sigwinch_sig(); | |
1445 | while(1){ | |
a6ea4cce | 1446 | n = os_read_file(kernel_fd, &req, |
2adcec21 JD |
1447 | sizeof(struct io_thread_req *)); |
1448 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1449 | if(n < 0) |
1450 | printk("io_thread - read failed, fd = %d, " | |
1451 | "err = %d\n", kernel_fd, -n); | |
1452 | else { | |
1453 | printk("io_thread - short read, fd = %d, " | |
1454 | "length = %d\n", kernel_fd, n); | |
1455 | } | |
1456 | continue; | |
1457 | } | |
1458 | io_count++; | |
2adcec21 | 1459 | do_io(req); |
a6ea4cce | 1460 | n = os_write_file(kernel_fd, &req, |
2adcec21 JD |
1461 | sizeof(struct io_thread_req *)); |
1462 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1463 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1464 | kernel_fd, -n); | |
1465 | } | |
91acb21f | 1466 | |
1b57e9c2 JD |
1467 | return 0; |
1468 | } |