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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 | ||
1da177e4 LT |
20 | #define UBD_SHIFT 4 |
21 | ||
8ea3c06a AV |
22 | #include <linux/module.h> |
23 | #include <linux/init.h> | |
24 | #include <linux/blkdev.h> | |
25 | #include <linux/ata.h> | |
26 | #include <linux/hdreg.h> | |
27 | #include <linux/cdrom.h> | |
28 | #include <linux/proc_fs.h> | |
29 | #include <linux/seq_file.h> | |
30 | #include <linux/ctype.h> | |
31 | #include <linux/slab.h> | |
32 | #include <linux/vmalloc.h> | |
33 | #include <linux/platform_device.h> | |
34 | #include <linux/scatterlist.h> | |
35 | #include <asm/tlbflush.h> | |
37185b33 | 36 | #include <kern_util.h> |
1da177e4 | 37 | #include "mconsole_kern.h" |
37185b33 AV |
38 | #include <init.h> |
39 | #include <irq_kern.h> | |
8ea3c06a | 40 | #include "ubd.h" |
37185b33 | 41 | #include <os.h> |
1da177e4 LT |
42 | #include "cow.h" |
43 | ||
805f11a0 | 44 | enum ubd_req { UBD_READ, UBD_WRITE, UBD_FLUSH }; |
1da177e4 LT |
45 | |
46 | struct io_thread_req { | |
62f96cb0 | 47 | struct request *req; |
91acb21f | 48 | enum ubd_req op; |
1da177e4 LT |
49 | int fds[2]; |
50 | unsigned long offsets[2]; | |
51 | unsigned long long offset; | |
52 | unsigned long length; | |
53 | char *buffer; | |
54 | int sectorsize; | |
91acb21f JD |
55 | unsigned long sector_mask; |
56 | unsigned long long cow_offset; | |
57 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
58 | int error; |
59 | }; | |
60 | ||
91acb21f | 61 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
62 | { |
63 | __u64 n; | |
64 | int bits, off; | |
65 | ||
91acb21f | 66 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
67 | n = bit / bits; |
68 | off = bit % bits; | |
dc764e50 | 69 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
70 | } |
71 | ||
91acb21f | 72 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
73 | { |
74 | __u64 n; | |
75 | int bits, off; | |
76 | ||
91acb21f | 77 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
78 | n = bit / bits; |
79 | off = bit % bits; | |
91acb21f | 80 | data[n] |= (1 << off); |
1da177e4 LT |
81 | } |
82 | /*End stuff from ubd_user.h*/ | |
83 | ||
84 | #define DRIVER_NAME "uml-blkdev" | |
85 | ||
d7fb2c38 | 86 | static DEFINE_MUTEX(ubd_lock); |
9a181c58 | 87 | static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ |
1da177e4 | 88 | |
a625c998 | 89 | static int ubd_open(struct block_device *bdev, fmode_t mode); |
db2a144b | 90 | static void ubd_release(struct gendisk *disk, fmode_t mode); |
a625c998 | 91 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 | 92 | unsigned int cmd, unsigned long arg); |
a885c8c4 | 93 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 94 | |
97d88ac8 | 95 | #define MAX_DEV (16) |
1da177e4 | 96 | |
83d5cde4 | 97 | static const struct block_device_operations ubd_blops = { |
1da177e4 | 98 | .owner = THIS_MODULE, |
a625c998 AV |
99 | .open = ubd_open, |
100 | .release = ubd_release, | |
101 | .ioctl = ubd_ioctl, | |
a885c8c4 | 102 | .getgeo = ubd_getgeo, |
1da177e4 LT |
103 | }; |
104 | ||
1da177e4 | 105 | /* Protected by ubd_lock */ |
792dd4fc | 106 | static int fake_major = UBD_MAJOR; |
1da177e4 LT |
107 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
108 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 109 | |
1da177e4 LT |
110 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
111 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
112 | .cl = 1 }) | |
113 | #else | |
114 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
115 | .cl = 1 }) | |
116 | #endif | |
1da177e4 LT |
117 | static struct openflags global_openflags = OPEN_FLAGS; |
118 | ||
119 | struct cow { | |
2a9d32f6 | 120 | /* backing file name */ |
1da177e4 | 121 | char *file; |
2a9d32f6 | 122 | /* backing file fd */ |
1da177e4 LT |
123 | int fd; |
124 | unsigned long *bitmap; | |
125 | unsigned long bitmap_len; | |
126 | int bitmap_offset; | |
dc764e50 | 127 | int data_offset; |
1da177e4 LT |
128 | }; |
129 | ||
a0044bdf JD |
130 | #define MAX_SG 64 |
131 | ||
1da177e4 | 132 | struct ubd { |
a0044bdf | 133 | struct list_head restart; |
2a9d32f6 PBG |
134 | /* name (and fd, below) of the file opened for writing, either the |
135 | * backing or the cow file. */ | |
1da177e4 LT |
136 | char *file; |
137 | int count; | |
138 | int fd; | |
139 | __u64 size; | |
140 | struct openflags boot_openflags; | |
141 | struct openflags openflags; | |
84e945e3 PBG |
142 | unsigned shared:1; |
143 | unsigned no_cow:1; | |
1da177e4 LT |
144 | struct cow cow; |
145 | struct platform_device pdev; | |
62f96cb0 JD |
146 | struct request_queue *queue; |
147 | spinlock_t lock; | |
a0044bdf JD |
148 | struct scatterlist sg[MAX_SG]; |
149 | struct request *request; | |
150 | int start_sg, end_sg; | |
47526903 | 151 | sector_t rq_pos; |
1da177e4 LT |
152 | }; |
153 | ||
154 | #define DEFAULT_COW { \ | |
155 | .file = NULL, \ | |
dc764e50 JD |
156 | .fd = -1, \ |
157 | .bitmap = NULL, \ | |
1da177e4 | 158 | .bitmap_offset = 0, \ |
dc764e50 | 159 | .data_offset = 0, \ |
1da177e4 LT |
160 | } |
161 | ||
162 | #define DEFAULT_UBD { \ | |
163 | .file = NULL, \ | |
164 | .count = 0, \ | |
165 | .fd = -1, \ | |
166 | .size = -1, \ | |
167 | .boot_openflags = OPEN_FLAGS, \ | |
168 | .openflags = OPEN_FLAGS, \ | |
dc764e50 | 169 | .no_cow = 0, \ |
6c29256c | 170 | .shared = 0, \ |
dc764e50 | 171 | .cow = DEFAULT_COW, \ |
22e65004 | 172 | .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ |
a0044bdf JD |
173 | .request = NULL, \ |
174 | .start_sg = 0, \ | |
175 | .end_sg = 0, \ | |
47526903 | 176 | .rq_pos = 0, \ |
1da177e4 LT |
177 | } |
178 | ||
b8831a1d | 179 | /* Protected by ubd_lock */ |
5dc62b1b | 180 | static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; |
1da177e4 | 181 | |
1da177e4 LT |
182 | /* Only changed by fake_ide_setup which is a setup */ |
183 | static int fake_ide = 0; | |
184 | static struct proc_dir_entry *proc_ide_root = NULL; | |
185 | static struct proc_dir_entry *proc_ide = NULL; | |
186 | ||
187 | static void make_proc_ide(void) | |
188 | { | |
189 | proc_ide_root = proc_mkdir("ide", NULL); | |
190 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
191 | } | |
192 | ||
6613c5e8 | 193 | static int fake_ide_media_proc_show(struct seq_file *m, void *v) |
1da177e4 | 194 | { |
6613c5e8 AD |
195 | seq_puts(m, "disk\n"); |
196 | return 0; | |
197 | } | |
198 | ||
199 | static int fake_ide_media_proc_open(struct inode *inode, struct file *file) | |
200 | { | |
201 | return single_open(file, fake_ide_media_proc_show, NULL); | |
1da177e4 LT |
202 | } |
203 | ||
6613c5e8 AD |
204 | static const struct file_operations fake_ide_media_proc_fops = { |
205 | .owner = THIS_MODULE, | |
206 | .open = fake_ide_media_proc_open, | |
207 | .read = seq_read, | |
208 | .llseek = seq_lseek, | |
209 | .release = single_release, | |
210 | }; | |
211 | ||
c0a9290e | 212 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
213 | { |
214 | struct proc_dir_entry *dir, *ent; | |
215 | char name[64]; | |
216 | ||
217 | if(proc_ide_root == NULL) make_proc_ide(); | |
218 | ||
219 | dir = proc_mkdir(dev_name, proc_ide); | |
220 | if(!dir) return; | |
221 | ||
6613c5e8 | 222 | ent = proc_create("media", S_IRUGO, dir, &fake_ide_media_proc_fops); |
1da177e4 | 223 | if(!ent) return; |
c0a9290e | 224 | snprintf(name, sizeof(name), "ide0/%s", dev_name); |
1da177e4 LT |
225 | proc_symlink(dev_name, proc_ide_root, name); |
226 | } | |
227 | ||
228 | static int fake_ide_setup(char *str) | |
229 | { | |
230 | fake_ide = 1; | |
dc764e50 | 231 | return 1; |
1da177e4 LT |
232 | } |
233 | ||
234 | __setup("fake_ide", fake_ide_setup); | |
235 | ||
236 | __uml_help(fake_ide_setup, | |
237 | "fake_ide\n" | |
238 | " Create ide0 entries that map onto ubd devices.\n\n" | |
239 | ); | |
240 | ||
241 | static int parse_unit(char **ptr) | |
242 | { | |
243 | char *str = *ptr, *end; | |
244 | int n = -1; | |
245 | ||
246 | if(isdigit(*str)) { | |
247 | n = simple_strtoul(str, &end, 0); | |
248 | if(end == str) | |
dc764e50 | 249 | return -1; |
1da177e4 LT |
250 | *ptr = end; |
251 | } | |
97d88ac8 | 252 | else if (('a' <= *str) && (*str <= 'z')) { |
1da177e4 LT |
253 | n = *str - 'a'; |
254 | str++; | |
255 | *ptr = str; | |
256 | } | |
dc764e50 | 257 | return n; |
1da177e4 LT |
258 | } |
259 | ||
d8d7c28e PBG |
260 | /* If *index_out == -1 at exit, the passed option was a general one; |
261 | * otherwise, the str pointer is used (and owned) inside ubd_devs array, so it | |
262 | * should not be freed on exit. | |
263 | */ | |
f28169d2 | 264 | static int ubd_setup_common(char *str, int *index_out, char **error_out) |
1da177e4 | 265 | { |
7d314e34 | 266 | struct ubd *ubd_dev; |
1da177e4 LT |
267 | struct openflags flags = global_openflags; |
268 | char *backing_file; | |
b8831a1d | 269 | int n, err = 0, i; |
1da177e4 LT |
270 | |
271 | if(index_out) *index_out = -1; | |
272 | n = *str; | |
273 | if(n == '='){ | |
274 | char *end; | |
275 | int major; | |
276 | ||
277 | str++; | |
1da177e4 LT |
278 | if(!strcmp(str, "sync")){ |
279 | global_openflags = of_sync(global_openflags); | |
b8831a1d | 280 | goto out1; |
1da177e4 | 281 | } |
b8831a1d JD |
282 | |
283 | err = -EINVAL; | |
1da177e4 LT |
284 | major = simple_strtoul(str, &end, 0); |
285 | if((*end != '\0') || (end == str)){ | |
f28169d2 | 286 | *error_out = "Didn't parse major number"; |
b8831a1d | 287 | goto out1; |
1da177e4 LT |
288 | } |
289 | ||
f28169d2 | 290 | mutex_lock(&ubd_lock); |
792dd4fc | 291 | if (fake_major != UBD_MAJOR) { |
f28169d2 JD |
292 | *error_out = "Can't assign a fake major twice"; |
293 | goto out1; | |
294 | } | |
6c29256c | 295 | |
f28169d2 | 296 | fake_major = major; |
1da177e4 LT |
297 | |
298 | printk(KERN_INFO "Setting extra ubd major number to %d\n", | |
299 | major); | |
f28169d2 JD |
300 | err = 0; |
301 | out1: | |
302 | mutex_unlock(&ubd_lock); | |
303 | return err; | |
1da177e4 LT |
304 | } |
305 | ||
306 | n = parse_unit(&str); | |
307 | if(n < 0){ | |
f28169d2 JD |
308 | *error_out = "Couldn't parse device number"; |
309 | return -EINVAL; | |
1da177e4 LT |
310 | } |
311 | if(n >= MAX_DEV){ | |
f28169d2 JD |
312 | *error_out = "Device number out of range"; |
313 | return 1; | |
1da177e4 LT |
314 | } |
315 | ||
f28169d2 | 316 | err = -EBUSY; |
d7fb2c38 | 317 | mutex_lock(&ubd_lock); |
1da177e4 | 318 | |
7d314e34 PBG |
319 | ubd_dev = &ubd_devs[n]; |
320 | if(ubd_dev->file != NULL){ | |
f28169d2 | 321 | *error_out = "Device is already configured"; |
1da177e4 LT |
322 | goto out; |
323 | } | |
324 | ||
325 | if (index_out) | |
326 | *index_out = n; | |
327 | ||
f28169d2 | 328 | err = -EINVAL; |
6c29256c | 329 | for (i = 0; i < sizeof("rscd="); i++) { |
1da177e4 LT |
330 | switch (*str) { |
331 | case 'r': | |
332 | flags.w = 0; | |
333 | break; | |
334 | case 's': | |
335 | flags.s = 1; | |
336 | break; | |
337 | case 'd': | |
7d314e34 | 338 | ubd_dev->no_cow = 1; |
1da177e4 | 339 | break; |
6c29256c | 340 | case 'c': |
7d314e34 | 341 | ubd_dev->shared = 1; |
6c29256c | 342 | break; |
1da177e4 LT |
343 | case '=': |
344 | str++; | |
345 | goto break_loop; | |
346 | default: | |
f28169d2 JD |
347 | *error_out = "Expected '=' or flag letter " |
348 | "(r, s, c, or d)"; | |
1da177e4 LT |
349 | goto out; |
350 | } | |
351 | str++; | |
352 | } | |
353 | ||
f28169d2 JD |
354 | if (*str == '=') |
355 | *error_out = "Too many flags specified"; | |
356 | else | |
357 | *error_out = "Missing '='"; | |
1da177e4 LT |
358 | goto out; |
359 | ||
360 | break_loop: | |
1da177e4 LT |
361 | backing_file = strchr(str, ','); |
362 | ||
f28169d2 | 363 | if (backing_file == NULL) |
1da177e4 | 364 | backing_file = strchr(str, ':'); |
1da177e4 | 365 | |
f28169d2 JD |
366 | if(backing_file != NULL){ |
367 | if(ubd_dev->no_cow){ | |
368 | *error_out = "Can't specify both 'd' and a cow file"; | |
369 | goto out; | |
370 | } | |
1da177e4 LT |
371 | else { |
372 | *backing_file = '\0'; | |
373 | backing_file++; | |
374 | } | |
375 | } | |
f28169d2 | 376 | err = 0; |
7d314e34 PBG |
377 | ubd_dev->file = str; |
378 | ubd_dev->cow.file = backing_file; | |
379 | ubd_dev->boot_openflags = flags; | |
1da177e4 | 380 | out: |
d7fb2c38 | 381 | mutex_unlock(&ubd_lock); |
f28169d2 | 382 | return err; |
1da177e4 LT |
383 | } |
384 | ||
385 | static int ubd_setup(char *str) | |
386 | { | |
f28169d2 JD |
387 | char *error; |
388 | int err; | |
389 | ||
390 | err = ubd_setup_common(str, NULL, &error); | |
391 | if(err) | |
392 | printk(KERN_ERR "Failed to initialize device with \"%s\" : " | |
393 | "%s\n", str, error); | |
394 | return 1; | |
1da177e4 LT |
395 | } |
396 | ||
397 | __setup("ubd", ubd_setup); | |
398 | __uml_help(ubd_setup, | |
399 | "ubd<n><flags>=<filename>[(:|,)<filename2>]\n" | |
400 | " This is used to associate a device with a file in the underlying\n" | |
401 | " filesystem. When specifying two filenames, the first one is the\n" | |
402 | " COW name and the second is the backing file name. As separator you can\n" | |
403 | " use either a ':' or a ',': the first one allows writing things like;\n" | |
404 | " ubd0=~/Uml/root_cow:~/Uml/root_backing_file\n" | |
405 | " while with a ',' the shell would not expand the 2nd '~'.\n" | |
f28169d2 | 406 | " When using only one filename, UML will detect whether to treat it like\n" |
1da177e4 LT |
407 | " a COW file or a backing file. To override this detection, add the 'd'\n" |
408 | " flag:\n" | |
409 | " ubd0d=BackingFile\n" | |
410 | " Usually, there is a filesystem in the file, but \n" | |
411 | " that's not required. Swap devices containing swap files can be\n" | |
412 | " specified like this. Also, a file which doesn't contain a\n" | |
413 | " filesystem can have its contents read in the virtual \n" | |
414 | " machine by running 'dd' on the device. <n> must be in the range\n" | |
415 | " 0 to 7. Appending an 'r' to the number will cause that device\n" | |
416 | " to be mounted read-only. For example ubd1r=./ext_fs. Appending\n" | |
20ede453 JD |
417 | " an 's' will cause data to be written to disk on the host immediately.\n" |
418 | " 'c' will cause the device to be treated as being shared between multiple\n" | |
419 | " UMLs and file locking will be turned off - this is appropriate for a\n" | |
420 | " cluster filesystem and inappropriate at almost all other times.\n\n" | |
1da177e4 LT |
421 | ); |
422 | ||
8299ca5c | 423 | static int udb_setup(char *str) |
1da177e4 LT |
424 | { |
425 | printk("udb%s specified on command line is almost certainly a ubd -> " | |
426 | "udb TYPO\n", str); | |
dc764e50 | 427 | return 1; |
1da177e4 LT |
428 | } |
429 | ||
430 | __setup("udb", udb_setup); | |
431 | __uml_help(udb_setup, | |
432 | "udb\n" | |
0894e27e JD |
433 | " This option is here solely to catch ubd -> udb typos, which can be\n" |
434 | " to impossible to catch visually unless you specifically look for\n" | |
435 | " them. The only result of any option starting with 'udb' is an error\n" | |
1da177e4 LT |
436 | " in the boot output.\n\n" |
437 | ); | |
438 | ||
165125e1 | 439 | static void do_ubd_request(struct request_queue * q); |
91acb21f JD |
440 | |
441 | /* Only changed by ubd_init, which is an initcall. */ | |
5dc62b1b | 442 | static int thread_fd = -1; |
a0044bdf JD |
443 | static LIST_HEAD(restart); |
444 | ||
2fe30a34 | 445 | /* XXX - move this inside ubd_intr. */ |
62f96cb0 | 446 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 447 | static void ubd_handler(void) |
1da177e4 | 448 | { |
2adcec21 | 449 | struct io_thread_req *req; |
a0044bdf JD |
450 | struct ubd *ubd; |
451 | struct list_head *list, *next_ele; | |
452 | unsigned long flags; | |
91acb21f JD |
453 | int n; |
454 | ||
a0044bdf | 455 | while(1){ |
a6ea4cce JD |
456 | n = os_read_file(thread_fd, &req, |
457 | sizeof(struct io_thread_req *)); | |
a0044bdf JD |
458 | if(n != sizeof(req)){ |
459 | if(n == -EAGAIN) | |
460 | break; | |
461 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
462 | "err = %d\n", -n); | |
463 | return; | |
464 | } | |
62f96cb0 | 465 | |
4d6c84d9 | 466 | blk_end_request(req->req, 0, req->length); |
2adcec21 | 467 | kfree(req); |
a0044bdf | 468 | } |
62f96cb0 | 469 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
470 | |
471 | list_for_each_safe(list, next_ele, &restart){ | |
472 | ubd = container_of(list, struct ubd, restart); | |
473 | list_del_init(&ubd->restart); | |
474 | spin_lock_irqsave(&ubd->lock, flags); | |
475 | do_ubd_request(ubd->queue); | |
476 | spin_unlock_irqrestore(&ubd->lock, flags); | |
477 | } | |
1da177e4 LT |
478 | } |
479 | ||
7bea96fd | 480 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 481 | { |
91acb21f | 482 | ubd_handler(); |
dc764e50 | 483 | return IRQ_HANDLED; |
91acb21f | 484 | } |
09ace81c | 485 | |
91acb21f JD |
486 | /* Only changed by ubd_init, which is an initcall. */ |
487 | static int io_pid = -1; | |
09ace81c | 488 | |
5dc62b1b | 489 | static void kill_io_thread(void) |
91acb21f | 490 | { |
6c29256c | 491 | if(io_pid != -1) |
91acb21f | 492 | os_kill_process(io_pid, 1); |
09ace81c | 493 | } |
1da177e4 | 494 | |
91acb21f JD |
495 | __uml_exitcall(kill_io_thread); |
496 | ||
d8d7c28e | 497 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
498 | { |
499 | char *file; | |
85356398 RW |
500 | int fd; |
501 | int err; | |
502 | ||
503 | __u32 version; | |
504 | __u32 align; | |
505 | char *backing_file; | |
506 | time_t mtime; | |
507 | unsigned long long size; | |
508 | int sector_size; | |
509 | int bitmap_offset; | |
510 | ||
511 | if (ubd_dev->file && ubd_dev->cow.file) { | |
512 | file = ubd_dev->cow.file; | |
513 | ||
514 | goto out; | |
515 | } | |
516 | ||
d4afcba9 | 517 | fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); |
85356398 RW |
518 | if (fd < 0) |
519 | return fd; | |
520 | ||
521 | err = read_cow_header(file_reader, &fd, &version, &backing_file, \ | |
522 | &mtime, &size, §or_size, &align, &bitmap_offset); | |
523 | os_close_file(fd); | |
1da177e4 | 524 | |
85356398 RW |
525 | if(err == -EINVAL) |
526 | file = ubd_dev->file; | |
527 | else | |
528 | file = backing_file; | |
529 | ||
530 | out: | |
dc764e50 | 531 | return os_file_size(file, size_out); |
1da177e4 LT |
532 | } |
533 | ||
5dc62b1b WC |
534 | static int read_cow_bitmap(int fd, void *buf, int offset, int len) |
535 | { | |
536 | int err; | |
537 | ||
8c6157b6 | 538 | err = os_pread_file(fd, buf, len, offset); |
5dc62b1b WC |
539 | if (err < 0) |
540 | return err; | |
541 | ||
542 | return 0; | |
543 | } | |
544 | ||
545 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
546 | { | |
547 | unsigned long modtime; | |
548 | unsigned long long actual; | |
549 | int err; | |
550 | ||
551 | err = os_file_modtime(file, &modtime); | |
552 | if (err < 0) { | |
553 | printk(KERN_ERR "Failed to get modification time of backing " | |
554 | "file \"%s\", err = %d\n", file, -err); | |
555 | return err; | |
556 | } | |
557 | ||
558 | err = os_file_size(file, &actual); | |
559 | if (err < 0) { | |
560 | printk(KERN_ERR "Failed to get size of backing file \"%s\", " | |
561 | "err = %d\n", file, -err); | |
562 | return err; | |
563 | } | |
564 | ||
565 | if (actual != size) { | |
566 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
567 | * the typecast.*/ | |
568 | printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " | |
569 | "vs backing file\n", (unsigned long long) size, actual); | |
570 | return -EINVAL; | |
571 | } | |
572 | if (modtime != mtime) { | |
573 | printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " | |
574 | "backing file\n", mtime, modtime); | |
575 | return -EINVAL; | |
576 | } | |
577 | return 0; | |
578 | } | |
579 | ||
580 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) | |
581 | { | |
582 | struct uml_stat buf1, buf2; | |
583 | int err; | |
584 | ||
585 | if (from_cmdline == NULL) | |
586 | return 0; | |
587 | if (!strcmp(from_cmdline, from_cow)) | |
588 | return 0; | |
589 | ||
590 | err = os_stat_file(from_cmdline, &buf1); | |
591 | if (err < 0) { | |
592 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, | |
593 | -err); | |
594 | return 0; | |
595 | } | |
596 | err = os_stat_file(from_cow, &buf2); | |
597 | if (err < 0) { | |
598 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, | |
599 | -err); | |
600 | return 1; | |
601 | } | |
602 | if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
603 | return 0; | |
604 | ||
605 | printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " | |
606 | "\"%s\" specified in COW header of \"%s\"\n", | |
607 | from_cmdline, from_cow, cow); | |
608 | return 1; | |
609 | } | |
610 | ||
611 | static int open_ubd_file(char *file, struct openflags *openflags, int shared, | |
612 | char **backing_file_out, int *bitmap_offset_out, | |
613 | unsigned long *bitmap_len_out, int *data_offset_out, | |
614 | int *create_cow_out) | |
615 | { | |
616 | time_t mtime; | |
617 | unsigned long long size; | |
618 | __u32 version, align; | |
619 | char *backing_file; | |
620 | int fd, err, sectorsize, asked_switch, mode = 0644; | |
621 | ||
622 | fd = os_open_file(file, *openflags, mode); | |
623 | if (fd < 0) { | |
624 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
625 | *create_cow_out = 1; | |
626 | if (!openflags->w || | |
627 | ((fd != -EROFS) && (fd != -EACCES))) | |
628 | return fd; | |
629 | openflags->w = 0; | |
630 | fd = os_open_file(file, *openflags, mode); | |
631 | if (fd < 0) | |
632 | return fd; | |
633 | } | |
634 | ||
635 | if (shared) | |
636 | printk(KERN_INFO "Not locking \"%s\" on the host\n", file); | |
637 | else { | |
638 | err = os_lock_file(fd, openflags->w); | |
639 | if (err < 0) { | |
640 | printk(KERN_ERR "Failed to lock '%s', err = %d\n", | |
641 | file, -err); | |
642 | goto out_close; | |
643 | } | |
644 | } | |
645 | ||
646 | /* Successful return case! */ | |
647 | if (backing_file_out == NULL) | |
648 | return fd; | |
649 | ||
650 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
651 | &size, §orsize, &align, bitmap_offset_out); | |
652 | if (err && (*backing_file_out != NULL)) { | |
653 | printk(KERN_ERR "Failed to read COW header from COW file " | |
654 | "\"%s\", errno = %d\n", file, -err); | |
655 | goto out_close; | |
656 | } | |
657 | if (err) | |
658 | return fd; | |
659 | ||
660 | asked_switch = path_requires_switch(*backing_file_out, backing_file, | |
661 | file); | |
662 | ||
663 | /* Allow switching only if no mismatch. */ | |
664 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, | |
665 | mtime)) { | |
666 | printk(KERN_ERR "Switching backing file to '%s'\n", | |
667 | *backing_file_out); | |
668 | err = write_cow_header(file, fd, *backing_file_out, | |
669 | sectorsize, align, &size); | |
670 | if (err) { | |
671 | printk(KERN_ERR "Switch failed, errno = %d\n", -err); | |
672 | goto out_close; | |
673 | } | |
674 | } else { | |
675 | *backing_file_out = backing_file; | |
676 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
677 | if (err) | |
678 | goto out_close; | |
679 | } | |
680 | ||
681 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
682 | bitmap_len_out, data_offset_out); | |
683 | ||
684 | return fd; | |
685 | out_close: | |
686 | os_close_file(fd); | |
687 | return err; | |
688 | } | |
689 | ||
690 | static int create_cow_file(char *cow_file, char *backing_file, | |
691 | struct openflags flags, | |
692 | int sectorsize, int alignment, int *bitmap_offset_out, | |
693 | unsigned long *bitmap_len_out, int *data_offset_out) | |
694 | { | |
695 | int err, fd; | |
696 | ||
697 | flags.c = 1; | |
698 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); | |
699 | if (fd < 0) { | |
700 | err = fd; | |
701 | printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", | |
702 | cow_file, -err); | |
703 | goto out; | |
704 | } | |
705 | ||
706 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
707 | bitmap_offset_out, bitmap_len_out, | |
708 | data_offset_out); | |
709 | if (!err) | |
710 | return fd; | |
711 | os_close_file(fd); | |
712 | out: | |
713 | return err; | |
714 | } | |
715 | ||
5f75a4f8 | 716 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 717 | { |
7d314e34 PBG |
718 | os_close_file(ubd_dev->fd); |
719 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
720 | return; |
721 | ||
7d314e34 PBG |
722 | os_close_file(ubd_dev->cow.fd); |
723 | vfree(ubd_dev->cow.bitmap); | |
724 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
725 | } |
726 | ||
7d314e34 | 727 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
728 | { |
729 | struct openflags flags; | |
730 | char **back_ptr; | |
731 | int err, create_cow, *create_ptr; | |
0bf16bff | 732 | int fd; |
1da177e4 | 733 | |
7d314e34 | 734 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 735 | create_cow = 0; |
7d314e34 PBG |
736 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
737 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
738 | |
739 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
740 | back_ptr, &ubd_dev->cow.bitmap_offset, |
741 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 742 | create_ptr); |
1da177e4 | 743 | |
0bf16bff PBG |
744 | if((fd == -ENOENT) && create_cow){ |
745 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
746 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
747 | &ubd_dev->cow.bitmap_offset, | |
748 | &ubd_dev->cow.bitmap_len, | |
749 | &ubd_dev->cow.data_offset); | |
0bf16bff | 750 | if(fd >= 0){ |
1da177e4 | 751 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 752 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
753 | } |
754 | } | |
755 | ||
0bf16bff | 756 | if(fd < 0){ |
7d314e34 | 757 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
758 | -fd); |
759 | return fd; | |
1da177e4 | 760 | } |
0bf16bff | 761 | ubd_dev->fd = fd; |
1da177e4 | 762 | |
7d314e34 | 763 | if(ubd_dev->cow.file != NULL){ |
086fa5ff | 764 | blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); |
f4768ffd | 765 | |
1da177e4 | 766 | err = -ENOMEM; |
da2486ba | 767 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 768 | if(ubd_dev->cow.bitmap == NULL){ |
1da177e4 LT |
769 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
770 | goto error; | |
771 | } | |
772 | flush_tlb_kernel_vm(); | |
773 | ||
7d314e34 PBG |
774 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
775 | ubd_dev->cow.bitmap_offset, | |
776 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
777 | if(err < 0) |
778 | goto error; | |
779 | ||
7d314e34 | 780 | flags = ubd_dev->openflags; |
1da177e4 | 781 | flags.w = 0; |
7d314e34 | 782 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 783 | NULL, NULL, NULL, NULL); |
1da177e4 | 784 | if(err < 0) goto error; |
7d314e34 | 785 | ubd_dev->cow.fd = err; |
1da177e4 | 786 | } |
dc764e50 | 787 | return 0; |
1da177e4 | 788 | error: |
7d314e34 | 789 | os_close_file(ubd_dev->fd); |
dc764e50 | 790 | return err; |
1da177e4 LT |
791 | } |
792 | ||
2e3f5251 JD |
793 | static void ubd_device_release(struct device *dev) |
794 | { | |
8691b97b | 795 | struct ubd *ubd_dev = dev_get_drvdata(dev); |
2e3f5251 JD |
796 | |
797 | blk_cleanup_queue(ubd_dev->queue); | |
798 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
799 | } | |
800 | ||
5f75a4f8 | 801 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 802 | struct gendisk **disk_out) |
1da177e4 LT |
803 | { |
804 | struct gendisk *disk; | |
1da177e4 LT |
805 | |
806 | disk = alloc_disk(1 << UBD_SHIFT); | |
807 | if(disk == NULL) | |
dc764e50 | 808 | return -ENOMEM; |
1da177e4 LT |
809 | |
810 | disk->major = major; | |
811 | disk->first_minor = unit << UBD_SHIFT; | |
812 | disk->fops = &ubd_blops; | |
813 | set_capacity(disk, size / 512); | |
792dd4fc | 814 | if (major == UBD_MAJOR) |
1da177e4 | 815 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 816 | else |
1da177e4 | 817 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
818 | |
819 | /* sysfs register (not for ide fake devices) */ | |
792dd4fc | 820 | if (major == UBD_MAJOR) { |
7d314e34 PBG |
821 | ubd_devs[unit].pdev.id = unit; |
822 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 | 823 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
8691b97b | 824 | dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); |
7d314e34 PBG |
825 | platform_device_register(&ubd_devs[unit].pdev); |
826 | disk->driverfs_dev = &ubd_devs[unit].pdev.dev; | |
1da177e4 LT |
827 | } |
828 | ||
7d314e34 | 829 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 830 | disk->queue = ubd_devs[unit].queue; |
1da177e4 LT |
831 | add_disk(disk); |
832 | ||
833 | *disk_out = disk; | |
834 | return 0; | |
835 | } | |
836 | ||
837 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
838 | ||
f28169d2 | 839 | static int ubd_add(int n, char **error_out) |
1da177e4 | 840 | { |
7d314e34 | 841 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 842 | int err = 0; |
1da177e4 | 843 | |
7d314e34 | 844 | if(ubd_dev->file == NULL) |
ec7cf783 | 845 | goto out; |
1da177e4 | 846 | |
7d314e34 | 847 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
848 | if(err < 0){ |
849 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 850 | goto out; |
f28169d2 | 851 | } |
1da177e4 | 852 | |
7d314e34 | 853 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 854 | |
a0044bdf | 855 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 856 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 857 | |
62f96cb0 JD |
858 | err = -ENOMEM; |
859 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
860 | if (ubd_dev->queue == NULL) { | |
861 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 862 | goto out; |
62f96cb0 JD |
863 | } |
864 | ubd_dev->queue->queuedata = ubd_dev; | |
f935a8ce | 865 | blk_queue_write_cache(ubd_dev->queue, true, false); |
62f96cb0 | 866 | |
8a78362c | 867 | blk_queue_max_segments(ubd_dev->queue, MAX_SG); |
792dd4fc | 868 | err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); |
62f96cb0 JD |
869 | if(err){ |
870 | *error_out = "Failed to register device"; | |
871 | goto out_cleanup; | |
872 | } | |
6c29256c | 873 | |
792dd4fc | 874 | if (fake_major != UBD_MAJOR) |
5f75a4f8 | 875 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 876 | &fake_gendisk[n]); |
1da177e4 | 877 | |
83380cc1 JD |
878 | /* |
879 | * Perhaps this should also be under the "if (fake_major)" above | |
880 | * using the fake_disk->disk_name | |
881 | */ | |
1da177e4 LT |
882 | if (fake_ide) |
883 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
884 | ||
ec7cf783 | 885 | err = 0; |
ec7cf783 JD |
886 | out: |
887 | return err; | |
62f96cb0 JD |
888 | |
889 | out_cleanup: | |
890 | blk_cleanup_queue(ubd_dev->queue); | |
891 | goto out; | |
1da177e4 LT |
892 | } |
893 | ||
f28169d2 | 894 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 895 | { |
e7f6552f | 896 | int n, ret; |
1da177e4 | 897 | |
f28169d2 JD |
898 | /* This string is possibly broken up and stored, so it's only |
899 | * freed if ubd_setup_common fails, or if only general options | |
900 | * were set. | |
901 | */ | |
970d6e3a | 902 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 903 | if (str == NULL) { |
f28169d2 JD |
904 | *error_out = "Failed to allocate memory"; |
905 | return -ENOMEM; | |
1da177e4 | 906 | } |
f28169d2 JD |
907 | |
908 | ret = ubd_setup_common(str, &n, error_out); | |
909 | if (ret) | |
e7f6552f | 910 | goto err_free; |
f28169d2 | 911 | |
e7f6552f PBG |
912 | if (n == -1) { |
913 | ret = 0; | |
d8d7c28e | 914 | goto err_free; |
1da177e4 | 915 | } |
1da177e4 | 916 | |
dc764e50 | 917 | mutex_lock(&ubd_lock); |
f28169d2 | 918 | ret = ubd_add(n, error_out); |
e7f6552f | 919 | if (ret) |
7d314e34 | 920 | ubd_devs[n].file = NULL; |
dc764e50 | 921 | mutex_unlock(&ubd_lock); |
1da177e4 | 922 | |
e7f6552f | 923 | out: |
dc764e50 | 924 | return ret; |
e7f6552f PBG |
925 | |
926 | err_free: | |
927 | kfree(str); | |
928 | goto out; | |
1da177e4 LT |
929 | } |
930 | ||
931 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
932 | { | |
7d314e34 | 933 | struct ubd *ubd_dev; |
1da177e4 LT |
934 | int n, len = 0; |
935 | ||
936 | n = parse_unit(&name); | |
937 | if((n >= MAX_DEV) || (n < 0)){ | |
938 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 939 | return -1; |
1da177e4 LT |
940 | } |
941 | ||
7d314e34 | 942 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 943 | mutex_lock(&ubd_lock); |
1da177e4 | 944 | |
7d314e34 | 945 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
946 | CONFIG_CHUNK(str, size, len, "", 1); |
947 | goto out; | |
948 | } | |
949 | ||
7d314e34 | 950 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 951 | |
7d314e34 | 952 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 953 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 954 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
955 | } |
956 | else CONFIG_CHUNK(str, size, len, "", 1); | |
957 | ||
958 | out: | |
d7fb2c38 | 959 | mutex_unlock(&ubd_lock); |
dc764e50 | 960 | return len; |
1da177e4 LT |
961 | } |
962 | ||
29d56cfe JD |
963 | static int ubd_id(char **str, int *start_out, int *end_out) |
964 | { | |
dc764e50 | 965 | int n; |
29d56cfe JD |
966 | |
967 | n = parse_unit(str); | |
dc764e50 JD |
968 | *start_out = 0; |
969 | *end_out = MAX_DEV - 1; | |
970 | return n; | |
29d56cfe JD |
971 | } |
972 | ||
f28169d2 | 973 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 974 | { |
2e3f5251 | 975 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 976 | struct ubd *ubd_dev; |
29d56cfe | 977 | int err = -ENODEV; |
1da177e4 | 978 | |
d7fb2c38 | 979 | mutex_lock(&ubd_lock); |
1da177e4 | 980 | |
7d314e34 | 981 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 982 | |
7d314e34 | 983 | if(ubd_dev->file == NULL) |
29d56cfe | 984 | goto out; |
1da177e4 | 985 | |
29d56cfe JD |
986 | /* you cannot remove a open disk */ |
987 | err = -EBUSY; | |
7d314e34 | 988 | if(ubd_dev->count > 0) |
1da177e4 LT |
989 | goto out; |
990 | ||
dc764e50 | 991 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
992 | if(disk != NULL){ |
993 | del_gendisk(disk); | |
994 | put_disk(disk); | |
995 | } | |
1da177e4 LT |
996 | |
997 | if(fake_gendisk[n] != NULL){ | |
998 | del_gendisk(fake_gendisk[n]); | |
999 | put_disk(fake_gendisk[n]); | |
1000 | fake_gendisk[n] = NULL; | |
1001 | } | |
1002 | ||
1da177e4 | 1003 | err = 0; |
2e3f5251 | 1004 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 1005 | out: |
d7fb2c38 | 1006 | mutex_unlock(&ubd_lock); |
29d56cfe | 1007 | return err; |
1da177e4 LT |
1008 | } |
1009 | ||
f28169d2 | 1010 | /* All these are called by mconsole in process context and without |
b8831a1d | 1011 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 1012 | */ |
1da177e4 | 1013 | static struct mc_device ubd_mc = { |
84f48d4f | 1014 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
1015 | .name = "ubd", |
1016 | .config = ubd_config, | |
dc764e50 | 1017 | .get_config = ubd_get_config, |
29d56cfe | 1018 | .id = ubd_id, |
1da177e4 LT |
1019 | .remove = ubd_remove, |
1020 | }; | |
1021 | ||
d8d7c28e | 1022 | static int __init ubd_mc_init(void) |
1da177e4 LT |
1023 | { |
1024 | mconsole_register_dev(&ubd_mc); | |
1025 | return 0; | |
1026 | } | |
1027 | ||
1028 | __initcall(ubd_mc_init); | |
1029 | ||
d8d7c28e PBG |
1030 | static int __init ubd0_init(void) |
1031 | { | |
1032 | struct ubd *ubd_dev = &ubd_devs[0]; | |
1033 | ||
b8831a1d | 1034 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
1035 | if(ubd_dev->file == NULL) |
1036 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
1037 | mutex_unlock(&ubd_lock); |
1038 | ||
dc764e50 | 1039 | return 0; |
d8d7c28e PBG |
1040 | } |
1041 | ||
1042 | __initcall(ubd0_init); | |
1043 | ||
b8831a1d | 1044 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
1045 | static struct platform_driver ubd_driver = { |
1046 | .driver = { | |
1047 | .name = DRIVER_NAME, | |
1048 | }, | |
1da177e4 LT |
1049 | }; |
1050 | ||
d8d7c28e | 1051 | static int __init ubd_init(void) |
1da177e4 | 1052 | { |
f28169d2 JD |
1053 | char *error; |
1054 | int i, err; | |
1da177e4 | 1055 | |
792dd4fc | 1056 | if (register_blkdev(UBD_MAJOR, "ubd")) |
1da177e4 LT |
1057 | return -1; |
1058 | ||
792dd4fc | 1059 | if (fake_major != UBD_MAJOR) { |
1da177e4 LT |
1060 | char name[sizeof("ubd_nnn\0")]; |
1061 | ||
1062 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
1063 | if (register_blkdev(fake_major, "ubd")) |
1064 | return -1; | |
1065 | } | |
3ae5eaec | 1066 | platform_driver_register(&ubd_driver); |
dc764e50 | 1067 | mutex_lock(&ubd_lock); |
f28169d2 JD |
1068 | for (i = 0; i < MAX_DEV; i++){ |
1069 | err = ubd_add(i, &error); | |
1070 | if(err) | |
1071 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
1072 | "%s\n", i, error); | |
1073 | } | |
dc764e50 | 1074 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
1075 | return 0; |
1076 | } | |
1077 | ||
1078 | late_initcall(ubd_init); | |
1079 | ||
d8d7c28e | 1080 | static int __init ubd_driver_init(void){ |
91acb21f JD |
1081 | unsigned long stack; |
1082 | int err; | |
1083 | ||
1084 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
1085 | if(global_openflags.s){ | |
1086 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
1087 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
1088 | * enough. So use anyway the io thread. */ | |
1089 | } | |
1090 | stack = alloc_stack(0, 0); | |
6c29256c | 1091 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
1092 | &thread_fd); |
1093 | if(io_pid < 0){ | |
6c29256c | 1094 | printk(KERN_ERR |
91acb21f JD |
1095 | "ubd : Failed to start I/O thread (errno = %d) - " |
1096 | "falling back to synchronous I/O\n", -io_pid); | |
1097 | io_pid = -1; | |
dc764e50 | 1098 | return 0; |
91acb21f | 1099 | } |
6c29256c | 1100 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
c0b79a90 | 1101 | 0, "ubd", ubd_devs); |
91acb21f JD |
1102 | if(err != 0) |
1103 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 1104 | return 0; |
91acb21f JD |
1105 | } |
1106 | ||
1107 | device_initcall(ubd_driver_init); | |
1108 | ||
a625c998 | 1109 | static int ubd_open(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1110 | { |
a625c998 | 1111 | struct gendisk *disk = bdev->bd_disk; |
7d314e34 | 1112 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
1113 | int err = 0; |
1114 | ||
9a181c58 | 1115 | mutex_lock(&ubd_mutex); |
7d314e34 PBG |
1116 | if(ubd_dev->count == 0){ |
1117 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
1118 | if(err){ |
1119 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 1120 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
1121 | goto out; |
1122 | } | |
1123 | } | |
7d314e34 PBG |
1124 | ubd_dev->count++; |
1125 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
1126 | |
1127 | /* This should no more be needed. And it didn't work anyway to exclude | |
1128 | * read-write remounting of filesystems.*/ | |
a625c998 | 1129 | /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 1130 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 1131 | err = -EROFS; |
2c49be99 | 1132 | }*/ |
6e9624b8 | 1133 | out: |
9a181c58 | 1134 | mutex_unlock(&ubd_mutex); |
dc764e50 | 1135 | return err; |
1da177e4 LT |
1136 | } |
1137 | ||
db2a144b | 1138 | static void ubd_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 1139 | { |
7d314e34 | 1140 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 1141 | |
9a181c58 | 1142 | mutex_lock(&ubd_mutex); |
7d314e34 | 1143 | if(--ubd_dev->count == 0) |
5f75a4f8 | 1144 | ubd_close_dev(ubd_dev); |
9a181c58 | 1145 | mutex_unlock(&ubd_mutex); |
1da177e4 LT |
1146 | } |
1147 | ||
91acb21f JD |
1148 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
1149 | __u64 *cow_offset, unsigned long *bitmap, | |
1150 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
1151 | __u64 bitmap_len) | |
1da177e4 | 1152 | { |
91acb21f JD |
1153 | __u64 sector = io_offset >> 9; |
1154 | int i, update_bitmap = 0; | |
1155 | ||
1156 | for(i = 0; i < length >> 9; i++){ | |
1157 | if(cow_mask != NULL) | |
1158 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1159 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1160 | continue; | |
1da177e4 | 1161 | |
91acb21f JD |
1162 | update_bitmap = 1; |
1163 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1164 | } | |
1165 | ||
1166 | if(!update_bitmap) | |
1167 | return; | |
1da177e4 | 1168 | |
91acb21f | 1169 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1170 | |
91acb21f JD |
1171 | /* This takes care of the case where we're exactly at the end of the |
1172 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1173 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1174 | * for the original diagnosis. | |
1175 | */ | |
6d074242 JO |
1176 | if (*cow_offset == (DIV_ROUND_UP(bitmap_len, |
1177 | sizeof(unsigned long)) - 1)) | |
91acb21f JD |
1178 | (*cow_offset)--; |
1179 | ||
1180 | bitmap_words[0] = bitmap[*cow_offset]; | |
1181 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1182 | ||
1183 | *cow_offset *= sizeof(unsigned long); | |
1184 | *cow_offset += bitmap_offset; | |
1185 | } | |
1186 | ||
1187 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1188 | __u64 bitmap_offset, __u64 bitmap_len) | |
1189 | { | |
1190 | __u64 sector = req->offset >> 9; | |
1191 | int i; | |
1192 | ||
1193 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1194 | panic("Operation too long"); | |
1195 | ||
1196 | if(req->op == UBD_READ) { | |
1197 | for(i = 0; i < req->length >> 9; i++){ | |
1198 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1199 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1200 | &req->sector_mask); |
dc764e50 | 1201 | } |
91acb21f JD |
1202 | } |
1203 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1204 | &req->cow_offset, bitmap, bitmap_offset, | |
1205 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1206 | } |
1207 | ||
62f96cb0 | 1208 | /* Called with dev->lock held */ |
a0044bdf JD |
1209 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1210 | unsigned long long offset, int page_offset, | |
1211 | int len, struct page *page) | |
1da177e4 LT |
1212 | { |
1213 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1214 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1215 | |
62f96cb0 | 1216 | io_req->req = req; |
a0044bdf JD |
1217 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1218 | ubd_dev->fd; | |
7d314e34 | 1219 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1220 | io_req->cow_offset = -1; |
1da177e4 LT |
1221 | io_req->offset = offset; |
1222 | io_req->length = len; | |
1223 | io_req->error = 0; | |
91acb21f JD |
1224 | io_req->sector_mask = 0; |
1225 | ||
1226 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1227 | io_req->offsets[0] = 0; |
7d314e34 | 1228 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1229 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1230 | io_req->sectorsize = 1 << 9; |
1231 | ||
7d314e34 | 1232 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1233 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1234 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1235 | |
1da177e4 LT |
1236 | } |
1237 | ||
805f11a0 RW |
1238 | /* Called with dev->lock held */ |
1239 | static void prepare_flush_request(struct request *req, | |
1240 | struct io_thread_req *io_req) | |
1241 | { | |
1242 | struct gendisk *disk = req->rq_disk; | |
1243 | struct ubd *ubd_dev = disk->private_data; | |
1244 | ||
1245 | io_req->req = req; | |
1246 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : | |
1247 | ubd_dev->fd; | |
1248 | io_req->op = UBD_FLUSH; | |
1249 | } | |
1250 | ||
bc1d72e7 RW |
1251 | static bool submit_request(struct io_thread_req *io_req, struct ubd *dev) |
1252 | { | |
1253 | int n = os_write_file(thread_fd, &io_req, | |
1254 | sizeof(io_req)); | |
1255 | if (n != sizeof(io_req)) { | |
1256 | if (n != -EAGAIN) | |
1257 | printk("write to io thread failed, " | |
1258 | "errno = %d\n", -n); | |
1259 | else if (list_empty(&dev->restart)) | |
1260 | list_add(&dev->restart, &restart); | |
1261 | ||
1262 | kfree(io_req); | |
1263 | return false; | |
1264 | } | |
1265 | return true; | |
1266 | } | |
1267 | ||
62f96cb0 | 1268 | /* Called with dev->lock held */ |
165125e1 | 1269 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1270 | { |
2adcec21 | 1271 | struct io_thread_req *io_req; |
1da177e4 | 1272 | struct request *req; |
a0044bdf JD |
1273 | |
1274 | while(1){ | |
2a9529a0 | 1275 | struct ubd *dev = q->queuedata; |
2a236122 | 1276 | if(dev->request == NULL){ |
9934c8c0 | 1277 | struct request *req = blk_fetch_request(q); |
a0044bdf JD |
1278 | if(req == NULL) |
1279 | return; | |
1280 | ||
1281 | dev->request = req; | |
47526903 | 1282 | dev->rq_pos = blk_rq_pos(req); |
a0044bdf JD |
1283 | dev->start_sg = 0; |
1284 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1285 | } | |
1286 | ||
1287 | req = dev->request; | |
805f11a0 RW |
1288 | |
1289 | if (req->cmd_flags & REQ_FLUSH) { | |
1290 | io_req = kmalloc(sizeof(struct io_thread_req), | |
1291 | GFP_ATOMIC); | |
1292 | if (io_req == NULL) { | |
1293 | if (list_empty(&dev->restart)) | |
1294 | list_add(&dev->restart, &restart); | |
1295 | return; | |
1296 | } | |
1297 | prepare_flush_request(req, io_req); | |
2a236122 TK |
1298 | if (submit_request(io_req, dev) == false) |
1299 | return; | |
805f11a0 RW |
1300 | } |
1301 | ||
a0044bdf JD |
1302 | while(dev->start_sg < dev->end_sg){ |
1303 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1304 | ||
2adcec21 | 1305 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1306 | GFP_ATOMIC); |
2adcec21 JD |
1307 | if(io_req == NULL){ |
1308 | if(list_empty(&dev->restart)) | |
1309 | list_add(&dev->restart, &restart); | |
1310 | return; | |
1311 | } | |
1312 | prepare_request(req, io_req, | |
47526903 | 1313 | (unsigned long long)dev->rq_pos << 9, |
45711f1a | 1314 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1315 | |
bc1d72e7 | 1316 | if (submit_request(io_req, dev) == false) |
a0044bdf | 1317 | return; |
a0044bdf | 1318 | |
47526903 | 1319 | dev->rq_pos += sg->length >> 9; |
a0044bdf | 1320 | dev->start_sg++; |
1da177e4 | 1321 | } |
a0044bdf JD |
1322 | dev->end_sg = 0; |
1323 | dev->request = NULL; | |
1da177e4 LT |
1324 | } |
1325 | } | |
1326 | ||
a885c8c4 CH |
1327 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1328 | { | |
7d314e34 | 1329 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1330 | |
1331 | geo->heads = 128; | |
1332 | geo->sectors = 32; | |
7d314e34 | 1333 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1334 | return 0; |
1335 | } | |
1336 | ||
a625c998 | 1337 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 LT |
1338 | unsigned int cmd, unsigned long arg) |
1339 | { | |
a625c998 | 1340 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
73855e13 | 1341 | u16 ubd_id[ATA_ID_WORDS]; |
1da177e4 LT |
1342 | |
1343 | switch (cmd) { | |
1da177e4 | 1344 | struct cdrom_volctrl volume; |
1da177e4 | 1345 | case HDIO_GET_IDENTITY: |
73855e13 BZ |
1346 | memset(&ubd_id, 0, ATA_ID_WORDS * 2); |
1347 | ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); | |
1348 | ubd_id[ATA_ID_HEADS] = 128; | |
1349 | ubd_id[ATA_ID_SECTORS] = 32; | |
1da177e4 LT |
1350 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1351 | sizeof(ubd_id))) | |
dc764e50 JD |
1352 | return -EFAULT; |
1353 | return 0; | |
b8831a1d | 1354 | |
1da177e4 LT |
1355 | case CDROMVOLREAD: |
1356 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1357 | return -EFAULT; |
1da177e4 LT |
1358 | volume.channel0 = 255; |
1359 | volume.channel1 = 255; | |
1360 | volume.channel2 = 255; | |
1361 | volume.channel3 = 255; | |
1362 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1363 | return -EFAULT; |
1364 | return 0; | |
1da177e4 | 1365 | } |
dc764e50 | 1366 | return -EINVAL; |
1da177e4 LT |
1367 | } |
1368 | ||
91acb21f | 1369 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1370 | { |
91acb21f | 1371 | int n; |
1da177e4 | 1372 | |
91acb21f | 1373 | if(req->cow_offset == -1) |
dc764e50 | 1374 | return 0; |
1da177e4 | 1375 | |
8c6157b6 AI |
1376 | n = os_pwrite_file(req->fds[1], &req->bitmap_words, |
1377 | sizeof(req->bitmap_words), req->cow_offset); | |
91acb21f JD |
1378 | if(n != sizeof(req->bitmap_words)){ |
1379 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1380 | req->fds[1]); | |
dc764e50 | 1381 | return 1; |
91acb21f | 1382 | } |
1da177e4 | 1383 | |
dc764e50 | 1384 | return 0; |
91acb21f | 1385 | } |
1da177e4 | 1386 | |
5dc62b1b | 1387 | static void do_io(struct io_thread_req *req) |
91acb21f JD |
1388 | { |
1389 | char *buf; | |
1390 | unsigned long len; | |
1391 | int n, nsectors, start, end, bit; | |
91acb21f JD |
1392 | __u64 off; |
1393 | ||
805f11a0 RW |
1394 | if (req->op == UBD_FLUSH) { |
1395 | /* fds[0] is always either the rw image or our cow file */ | |
1396 | n = os_sync_file(req->fds[0]); | |
1397 | if (n != 0) { | |
1398 | printk("do_io - sync failed err = %d " | |
1399 | "fd = %d\n", -n, req->fds[0]); | |
1400 | req->error = 1; | |
1401 | } | |
1402 | return; | |
1403 | } | |
1404 | ||
91acb21f JD |
1405 | nsectors = req->length / req->sectorsize; |
1406 | start = 0; | |
1407 | do { | |
1408 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1409 | end = start; | |
1410 | while((end < nsectors) && | |
1411 | (ubd_test_bit(end, (unsigned char *) | |
1412 | &req->sector_mask) == bit)) | |
1413 | end++; | |
1414 | ||
1415 | off = req->offset + req->offsets[bit] + | |
1416 | start * req->sectorsize; | |
1417 | len = (end - start) * req->sectorsize; | |
1418 | buf = &req->buffer[start * req->sectorsize]; | |
1419 | ||
91acb21f JD |
1420 | if(req->op == UBD_READ){ |
1421 | n = 0; | |
1422 | do { | |
1423 | buf = &buf[n]; | |
1424 | len -= n; | |
8c6157b6 | 1425 | n = os_pread_file(req->fds[bit], buf, len, off); |
91acb21f JD |
1426 | if (n < 0) { |
1427 | printk("do_io - read failed, err = %d " | |
1428 | "fd = %d\n", -n, req->fds[bit]); | |
1429 | req->error = 1; | |
1430 | return; | |
1431 | } | |
1432 | } while((n < len) && (n != 0)); | |
1433 | if (n < len) memset(&buf[n], 0, len - n); | |
1434 | } else { | |
8c6157b6 | 1435 | n = os_pwrite_file(req->fds[bit], buf, len, off); |
91acb21f JD |
1436 | if(n != len){ |
1437 | printk("do_io - write failed err = %d " | |
1438 | "fd = %d\n", -n, req->fds[bit]); | |
1439 | req->error = 1; | |
1440 | return; | |
1441 | } | |
1442 | } | |
1443 | ||
1444 | start = end; | |
1445 | } while(start < nsectors); | |
1da177e4 | 1446 | |
91acb21f | 1447 | req->error = update_bitmap(req); |
1da177e4 | 1448 | } |
91acb21f JD |
1449 | |
1450 | /* Changed in start_io_thread, which is serialized by being called only | |
1451 | * from ubd_init, which is an initcall. | |
1452 | */ | |
1453 | int kernel_fd = -1; | |
1454 | ||
d8d7c28e PBG |
1455 | /* Only changed by the io thread. XXX: currently unused. */ |
1456 | static int io_count = 0; | |
91acb21f JD |
1457 | |
1458 | int io_thread(void *arg) | |
1459 | { | |
2adcec21 | 1460 | struct io_thread_req *req; |
91acb21f JD |
1461 | int n; |
1462 | ||
91d44ff8 RW |
1463 | os_fix_helper_signals(); |
1464 | ||
91acb21f | 1465 | while(1){ |
a6ea4cce | 1466 | n = os_read_file(kernel_fd, &req, |
2adcec21 JD |
1467 | sizeof(struct io_thread_req *)); |
1468 | if(n != sizeof(struct io_thread_req *)){ | |
91acb21f JD |
1469 | if(n < 0) |
1470 | printk("io_thread - read failed, fd = %d, " | |
1471 | "err = %d\n", kernel_fd, -n); | |
1472 | else { | |
1473 | printk("io_thread - short read, fd = %d, " | |
1474 | "length = %d\n", kernel_fd, n); | |
1475 | } | |
1476 | continue; | |
1477 | } | |
1478 | io_count++; | |
2adcec21 | 1479 | do_io(req); |
a6ea4cce | 1480 | n = os_write_file(kernel_fd, &req, |
2adcec21 JD |
1481 | sizeof(struct io_thread_req *)); |
1482 | if(n != sizeof(struct io_thread_req *)) | |
91acb21f JD |
1483 | printk("io_thread - write failed, fd = %d, err = %d\n", |
1484 | kernel_fd, -n); | |
1485 | } | |
91acb21f | 1486 | |
1b57e9c2 JD |
1487 | return 0; |
1488 | } |