Commit | Line | Data |
---|---|---|
6c29256c | 1 | /* |
f88f0bdf | 2 | * Copyright (C) 2015-2016 Anton Ivanov (aivanov@brocade.com) |
1da177e4 LT |
3 | * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
4 | * Licensed under the GPL | |
5 | */ | |
6 | ||
7 | /* 2001-09-28...2002-04-17 | |
8 | * Partition stuff by James_McMechan@hotmail.com | |
9 | * old style ubd by setting UBD_SHIFT to 0 | |
10 | * 2002-09-27...2002-10-18 massive tinkering for 2.5 | |
11 | * partitions have changed in 2.5 | |
12 | * 2003-01-29 more tinkering for 2.5.59-1 | |
13 | * This should now address the sysfs problems and has | |
14 | * the symlink for devfs to allow for booting with | |
15 | * the common /dev/ubd/discX/... names rather than | |
16 | * only /dev/ubdN/discN this version also has lots of | |
17 | * clean ups preparing for ubd-many. | |
18 | * James McMechan | |
19 | */ | |
20 | ||
1da177e4 LT |
21 | #define UBD_SHIFT 4 |
22 | ||
8ea3c06a AV |
23 | #include <linux/module.h> |
24 | #include <linux/init.h> | |
25 | #include <linux/blkdev.h> | |
26 | #include <linux/ata.h> | |
27 | #include <linux/hdreg.h> | |
28 | #include <linux/cdrom.h> | |
29 | #include <linux/proc_fs.h> | |
30 | #include <linux/seq_file.h> | |
31 | #include <linux/ctype.h> | |
32 | #include <linux/slab.h> | |
33 | #include <linux/vmalloc.h> | |
34 | #include <linux/platform_device.h> | |
35 | #include <linux/scatterlist.h> | |
36 | #include <asm/tlbflush.h> | |
37185b33 | 37 | #include <kern_util.h> |
1da177e4 | 38 | #include "mconsole_kern.h" |
37185b33 AV |
39 | #include <init.h> |
40 | #include <irq_kern.h> | |
8ea3c06a | 41 | #include "ubd.h" |
37185b33 | 42 | #include <os.h> |
1da177e4 LT |
43 | #include "cow.h" |
44 | ||
805f11a0 | 45 | enum ubd_req { UBD_READ, UBD_WRITE, UBD_FLUSH }; |
1da177e4 LT |
46 | |
47 | struct io_thread_req { | |
62f96cb0 | 48 | struct request *req; |
91acb21f | 49 | enum ubd_req op; |
1da177e4 LT |
50 | int fds[2]; |
51 | unsigned long offsets[2]; | |
52 | unsigned long long offset; | |
53 | unsigned long length; | |
54 | char *buffer; | |
55 | int sectorsize; | |
91acb21f JD |
56 | unsigned long sector_mask; |
57 | unsigned long long cow_offset; | |
58 | unsigned long bitmap_words[2]; | |
1da177e4 LT |
59 | int error; |
60 | }; | |
61 | ||
f88f0bdf AI |
62 | |
63 | static struct io_thread_req * (*irq_req_buffer)[]; | |
64 | static struct io_thread_req *irq_remainder; | |
65 | static int irq_remainder_size; | |
66 | ||
67 | static struct io_thread_req * (*io_req_buffer)[]; | |
68 | static struct io_thread_req *io_remainder; | |
69 | static int io_remainder_size; | |
70 | ||
71 | ||
72 | ||
91acb21f | 73 | static inline int ubd_test_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
74 | { |
75 | __u64 n; | |
76 | int bits, off; | |
77 | ||
91acb21f | 78 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
79 | n = bit / bits; |
80 | off = bit % bits; | |
dc764e50 | 81 | return (data[n] & (1 << off)) != 0; |
1da177e4 LT |
82 | } |
83 | ||
91acb21f | 84 | static inline void ubd_set_bit(__u64 bit, unsigned char *data) |
1da177e4 LT |
85 | { |
86 | __u64 n; | |
87 | int bits, off; | |
88 | ||
91acb21f | 89 | bits = sizeof(data[0]) * 8; |
1da177e4 LT |
90 | n = bit / bits; |
91 | off = bit % bits; | |
91acb21f | 92 | data[n] |= (1 << off); |
1da177e4 LT |
93 | } |
94 | /*End stuff from ubd_user.h*/ | |
95 | ||
96 | #define DRIVER_NAME "uml-blkdev" | |
97 | ||
d7fb2c38 | 98 | static DEFINE_MUTEX(ubd_lock); |
9a181c58 | 99 | static DEFINE_MUTEX(ubd_mutex); /* replaces BKL, might not be needed */ |
1da177e4 | 100 | |
a625c998 | 101 | static int ubd_open(struct block_device *bdev, fmode_t mode); |
db2a144b | 102 | static void ubd_release(struct gendisk *disk, fmode_t mode); |
a625c998 | 103 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 | 104 | unsigned int cmd, unsigned long arg); |
a885c8c4 | 105 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo); |
1da177e4 | 106 | |
97d88ac8 | 107 | #define MAX_DEV (16) |
1da177e4 | 108 | |
83d5cde4 | 109 | static const struct block_device_operations ubd_blops = { |
1da177e4 | 110 | .owner = THIS_MODULE, |
a625c998 AV |
111 | .open = ubd_open, |
112 | .release = ubd_release, | |
113 | .ioctl = ubd_ioctl, | |
a885c8c4 | 114 | .getgeo = ubd_getgeo, |
1da177e4 LT |
115 | }; |
116 | ||
1da177e4 | 117 | /* Protected by ubd_lock */ |
792dd4fc | 118 | static int fake_major = UBD_MAJOR; |
1da177e4 LT |
119 | static struct gendisk *ubd_gendisk[MAX_DEV]; |
120 | static struct gendisk *fake_gendisk[MAX_DEV]; | |
6c29256c | 121 | |
1da177e4 LT |
122 | #ifdef CONFIG_BLK_DEV_UBD_SYNC |
123 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 1, .c = 0, \ | |
124 | .cl = 1 }) | |
125 | #else | |
126 | #define OPEN_FLAGS ((struct openflags) { .r = 1, .w = 1, .s = 0, .c = 0, \ | |
127 | .cl = 1 }) | |
128 | #endif | |
1da177e4 LT |
129 | static struct openflags global_openflags = OPEN_FLAGS; |
130 | ||
131 | struct cow { | |
2a9d32f6 | 132 | /* backing file name */ |
1da177e4 | 133 | char *file; |
2a9d32f6 | 134 | /* backing file fd */ |
1da177e4 LT |
135 | int fd; |
136 | unsigned long *bitmap; | |
137 | unsigned long bitmap_len; | |
138 | int bitmap_offset; | |
dc764e50 | 139 | int data_offset; |
1da177e4 LT |
140 | }; |
141 | ||
a0044bdf JD |
142 | #define MAX_SG 64 |
143 | ||
1da177e4 | 144 | struct ubd { |
a0044bdf | 145 | struct list_head restart; |
2a9d32f6 PBG |
146 | /* name (and fd, below) of the file opened for writing, either the |
147 | * backing or the cow file. */ | |
1da177e4 LT |
148 | char *file; |
149 | int count; | |
150 | int fd; | |
151 | __u64 size; | |
152 | struct openflags boot_openflags; | |
153 | struct openflags openflags; | |
84e945e3 PBG |
154 | unsigned shared:1; |
155 | unsigned no_cow:1; | |
1da177e4 LT |
156 | struct cow cow; |
157 | struct platform_device pdev; | |
62f96cb0 JD |
158 | struct request_queue *queue; |
159 | spinlock_t lock; | |
a0044bdf JD |
160 | struct scatterlist sg[MAX_SG]; |
161 | struct request *request; | |
162 | int start_sg, end_sg; | |
47526903 | 163 | sector_t rq_pos; |
1da177e4 LT |
164 | }; |
165 | ||
166 | #define DEFAULT_COW { \ | |
167 | .file = NULL, \ | |
dc764e50 JD |
168 | .fd = -1, \ |
169 | .bitmap = NULL, \ | |
1da177e4 | 170 | .bitmap_offset = 0, \ |
dc764e50 | 171 | .data_offset = 0, \ |
1da177e4 LT |
172 | } |
173 | ||
174 | #define DEFAULT_UBD { \ | |
175 | .file = NULL, \ | |
176 | .count = 0, \ | |
177 | .fd = -1, \ | |
178 | .size = -1, \ | |
179 | .boot_openflags = OPEN_FLAGS, \ | |
180 | .openflags = OPEN_FLAGS, \ | |
dc764e50 | 181 | .no_cow = 0, \ |
6c29256c | 182 | .shared = 0, \ |
dc764e50 | 183 | .cow = DEFAULT_COW, \ |
22e65004 | 184 | .lock = __SPIN_LOCK_UNLOCKED(ubd_devs.lock), \ |
a0044bdf JD |
185 | .request = NULL, \ |
186 | .start_sg = 0, \ | |
187 | .end_sg = 0, \ | |
47526903 | 188 | .rq_pos = 0, \ |
1da177e4 LT |
189 | } |
190 | ||
b8831a1d | 191 | /* Protected by ubd_lock */ |
5dc62b1b | 192 | static struct ubd ubd_devs[MAX_DEV] = { [0 ... MAX_DEV - 1] = DEFAULT_UBD }; |
1da177e4 | 193 | |
1da177e4 LT |
194 | /* Only changed by fake_ide_setup which is a setup */ |
195 | static int fake_ide = 0; | |
196 | static struct proc_dir_entry *proc_ide_root = NULL; | |
197 | static struct proc_dir_entry *proc_ide = NULL; | |
198 | ||
199 | static void make_proc_ide(void) | |
200 | { | |
201 | proc_ide_root = proc_mkdir("ide", NULL); | |
202 | proc_ide = proc_mkdir("ide0", proc_ide_root); | |
203 | } | |
204 | ||
6613c5e8 | 205 | static int fake_ide_media_proc_show(struct seq_file *m, void *v) |
1da177e4 | 206 | { |
6613c5e8 AD |
207 | seq_puts(m, "disk\n"); |
208 | return 0; | |
209 | } | |
210 | ||
c0a9290e | 211 | static void make_ide_entries(const char *dev_name) |
1da177e4 LT |
212 | { |
213 | struct proc_dir_entry *dir, *ent; | |
214 | char name[64]; | |
215 | ||
216 | if(proc_ide_root == NULL) make_proc_ide(); | |
217 | ||
218 | dir = proc_mkdir(dev_name, proc_ide); | |
219 | if(!dir) return; | |
220 | ||
3f3942ac CH |
221 | ent = proc_create_single("media", S_IRUGO, dir, |
222 | fake_ide_media_proc_show); | |
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 | ||
f88f0bdf AI |
445 | /* Function to read several request pointers at a time |
446 | * handling fractional reads if (and as) needed | |
447 | */ | |
448 | ||
449 | static int bulk_req_safe_read( | |
450 | int fd, | |
451 | struct io_thread_req * (*request_buffer)[], | |
452 | struct io_thread_req **remainder, | |
453 | int *remainder_size, | |
454 | int max_recs | |
455 | ) | |
456 | { | |
457 | int n = 0; | |
458 | int res = 0; | |
459 | ||
460 | if (*remainder_size > 0) { | |
461 | memmove( | |
462 | (char *) request_buffer, | |
463 | (char *) remainder, *remainder_size | |
464 | ); | |
465 | n = *remainder_size; | |
466 | } | |
467 | ||
468 | res = os_read_file( | |
469 | fd, | |
470 | ((char *) request_buffer) + *remainder_size, | |
471 | sizeof(struct io_thread_req *)*max_recs | |
472 | - *remainder_size | |
473 | ); | |
474 | if (res > 0) { | |
475 | n += res; | |
476 | if ((n % sizeof(struct io_thread_req *)) > 0) { | |
477 | /* | |
478 | * Read somehow returned not a multiple of dword | |
479 | * theoretically possible, but never observed in the | |
480 | * wild, so read routine must be able to handle it | |
481 | */ | |
482 | *remainder_size = n % sizeof(struct io_thread_req *); | |
483 | WARN(*remainder_size > 0, "UBD IPC read returned a partial result"); | |
484 | memmove( | |
485 | remainder, | |
486 | ((char *) request_buffer) + | |
487 | (n/sizeof(struct io_thread_req *))*sizeof(struct io_thread_req *), | |
488 | *remainder_size | |
489 | ); | |
490 | n = n - *remainder_size; | |
491 | } | |
492 | } else { | |
493 | n = res; | |
494 | } | |
495 | return n; | |
496 | } | |
497 | ||
62f96cb0 | 498 | /* Called without dev->lock held, and only in interrupt context. */ |
91acb21f | 499 | static void ubd_handler(void) |
1da177e4 | 500 | { |
a0044bdf JD |
501 | struct ubd *ubd; |
502 | struct list_head *list, *next_ele; | |
503 | unsigned long flags; | |
91acb21f | 504 | int n; |
f88f0bdf | 505 | int count; |
91acb21f | 506 | |
a0044bdf | 507 | while(1){ |
f88f0bdf AI |
508 | n = bulk_req_safe_read( |
509 | thread_fd, | |
510 | irq_req_buffer, | |
511 | &irq_remainder, | |
512 | &irq_remainder_size, | |
513 | UBD_REQ_BUFFER_SIZE | |
514 | ); | |
515 | if (n < 0) { | |
a0044bdf JD |
516 | if(n == -EAGAIN) |
517 | break; | |
518 | printk(KERN_ERR "spurious interrupt in ubd_handler, " | |
519 | "err = %d\n", -n); | |
520 | return; | |
521 | } | |
f88f0bdf AI |
522 | for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { |
523 | blk_end_request( | |
524 | (*irq_req_buffer)[count]->req, | |
2a842aca | 525 | BLK_STS_OK, |
f88f0bdf AI |
526 | (*irq_req_buffer)[count]->length |
527 | ); | |
528 | kfree((*irq_req_buffer)[count]); | |
529 | } | |
a0044bdf | 530 | } |
62f96cb0 | 531 | reactivate_fd(thread_fd, UBD_IRQ); |
a0044bdf JD |
532 | |
533 | list_for_each_safe(list, next_ele, &restart){ | |
534 | ubd = container_of(list, struct ubd, restart); | |
535 | list_del_init(&ubd->restart); | |
536 | spin_lock_irqsave(&ubd->lock, flags); | |
537 | do_ubd_request(ubd->queue); | |
538 | spin_unlock_irqrestore(&ubd->lock, flags); | |
539 | } | |
1da177e4 LT |
540 | } |
541 | ||
7bea96fd | 542 | static irqreturn_t ubd_intr(int irq, void *dev) |
1da177e4 | 543 | { |
91acb21f | 544 | ubd_handler(); |
dc764e50 | 545 | return IRQ_HANDLED; |
91acb21f | 546 | } |
09ace81c | 547 | |
91acb21f JD |
548 | /* Only changed by ubd_init, which is an initcall. */ |
549 | static int io_pid = -1; | |
09ace81c | 550 | |
5dc62b1b | 551 | static void kill_io_thread(void) |
91acb21f | 552 | { |
6c29256c | 553 | if(io_pid != -1) |
91acb21f | 554 | os_kill_process(io_pid, 1); |
09ace81c | 555 | } |
1da177e4 | 556 | |
91acb21f JD |
557 | __uml_exitcall(kill_io_thread); |
558 | ||
d8d7c28e | 559 | static inline int ubd_file_size(struct ubd *ubd_dev, __u64 *size_out) |
1da177e4 LT |
560 | { |
561 | char *file; | |
85356398 RW |
562 | int fd; |
563 | int err; | |
564 | ||
565 | __u32 version; | |
566 | __u32 align; | |
567 | char *backing_file; | |
568 | time_t mtime; | |
569 | unsigned long long size; | |
570 | int sector_size; | |
571 | int bitmap_offset; | |
572 | ||
573 | if (ubd_dev->file && ubd_dev->cow.file) { | |
574 | file = ubd_dev->cow.file; | |
575 | ||
576 | goto out; | |
577 | } | |
578 | ||
d4afcba9 | 579 | fd = os_open_file(ubd_dev->file, of_read(OPENFLAGS()), 0); |
85356398 RW |
580 | if (fd < 0) |
581 | return fd; | |
582 | ||
583 | err = read_cow_header(file_reader, &fd, &version, &backing_file, \ | |
584 | &mtime, &size, §or_size, &align, &bitmap_offset); | |
585 | os_close_file(fd); | |
1da177e4 | 586 | |
85356398 RW |
587 | if(err == -EINVAL) |
588 | file = ubd_dev->file; | |
589 | else | |
590 | file = backing_file; | |
591 | ||
592 | out: | |
dc764e50 | 593 | return os_file_size(file, size_out); |
1da177e4 LT |
594 | } |
595 | ||
5dc62b1b WC |
596 | static int read_cow_bitmap(int fd, void *buf, int offset, int len) |
597 | { | |
598 | int err; | |
599 | ||
8c6157b6 | 600 | err = os_pread_file(fd, buf, len, offset); |
5dc62b1b WC |
601 | if (err < 0) |
602 | return err; | |
603 | ||
604 | return 0; | |
605 | } | |
606 | ||
607 | static int backing_file_mismatch(char *file, __u64 size, time_t mtime) | |
608 | { | |
609 | unsigned long modtime; | |
610 | unsigned long long actual; | |
611 | int err; | |
612 | ||
613 | err = os_file_modtime(file, &modtime); | |
614 | if (err < 0) { | |
615 | printk(KERN_ERR "Failed to get modification time of backing " | |
616 | "file \"%s\", err = %d\n", file, -err); | |
617 | return err; | |
618 | } | |
619 | ||
620 | err = os_file_size(file, &actual); | |
621 | if (err < 0) { | |
622 | printk(KERN_ERR "Failed to get size of backing file \"%s\", " | |
623 | "err = %d\n", file, -err); | |
624 | return err; | |
625 | } | |
626 | ||
627 | if (actual != size) { | |
628 | /*__u64 can be a long on AMD64 and with %lu GCC complains; so | |
629 | * the typecast.*/ | |
630 | printk(KERN_ERR "Size mismatch (%llu vs %llu) of COW header " | |
631 | "vs backing file\n", (unsigned long long) size, actual); | |
632 | return -EINVAL; | |
633 | } | |
634 | if (modtime != mtime) { | |
635 | printk(KERN_ERR "mtime mismatch (%ld vs %ld) of COW header vs " | |
636 | "backing file\n", mtime, modtime); | |
637 | return -EINVAL; | |
638 | } | |
639 | return 0; | |
640 | } | |
641 | ||
642 | static int path_requires_switch(char *from_cmdline, char *from_cow, char *cow) | |
643 | { | |
644 | struct uml_stat buf1, buf2; | |
645 | int err; | |
646 | ||
647 | if (from_cmdline == NULL) | |
648 | return 0; | |
649 | if (!strcmp(from_cmdline, from_cow)) | |
650 | return 0; | |
651 | ||
652 | err = os_stat_file(from_cmdline, &buf1); | |
653 | if (err < 0) { | |
654 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cmdline, | |
655 | -err); | |
656 | return 0; | |
657 | } | |
658 | err = os_stat_file(from_cow, &buf2); | |
659 | if (err < 0) { | |
660 | printk(KERN_ERR "Couldn't stat '%s', err = %d\n", from_cow, | |
661 | -err); | |
662 | return 1; | |
663 | } | |
664 | if ((buf1.ust_dev == buf2.ust_dev) && (buf1.ust_ino == buf2.ust_ino)) | |
665 | return 0; | |
666 | ||
667 | printk(KERN_ERR "Backing file mismatch - \"%s\" requested, " | |
668 | "\"%s\" specified in COW header of \"%s\"\n", | |
669 | from_cmdline, from_cow, cow); | |
670 | return 1; | |
671 | } | |
672 | ||
673 | static int open_ubd_file(char *file, struct openflags *openflags, int shared, | |
674 | char **backing_file_out, int *bitmap_offset_out, | |
675 | unsigned long *bitmap_len_out, int *data_offset_out, | |
676 | int *create_cow_out) | |
677 | { | |
678 | time_t mtime; | |
679 | unsigned long long size; | |
680 | __u32 version, align; | |
681 | char *backing_file; | |
682 | int fd, err, sectorsize, asked_switch, mode = 0644; | |
683 | ||
684 | fd = os_open_file(file, *openflags, mode); | |
685 | if (fd < 0) { | |
686 | if ((fd == -ENOENT) && (create_cow_out != NULL)) | |
687 | *create_cow_out = 1; | |
688 | if (!openflags->w || | |
689 | ((fd != -EROFS) && (fd != -EACCES))) | |
690 | return fd; | |
691 | openflags->w = 0; | |
692 | fd = os_open_file(file, *openflags, mode); | |
693 | if (fd < 0) | |
694 | return fd; | |
695 | } | |
696 | ||
697 | if (shared) | |
698 | printk(KERN_INFO "Not locking \"%s\" on the host\n", file); | |
699 | else { | |
700 | err = os_lock_file(fd, openflags->w); | |
701 | if (err < 0) { | |
702 | printk(KERN_ERR "Failed to lock '%s', err = %d\n", | |
703 | file, -err); | |
704 | goto out_close; | |
705 | } | |
706 | } | |
707 | ||
708 | /* Successful return case! */ | |
709 | if (backing_file_out == NULL) | |
710 | return fd; | |
711 | ||
712 | err = read_cow_header(file_reader, &fd, &version, &backing_file, &mtime, | |
713 | &size, §orsize, &align, bitmap_offset_out); | |
714 | if (err && (*backing_file_out != NULL)) { | |
715 | printk(KERN_ERR "Failed to read COW header from COW file " | |
716 | "\"%s\", errno = %d\n", file, -err); | |
717 | goto out_close; | |
718 | } | |
719 | if (err) | |
720 | return fd; | |
721 | ||
722 | asked_switch = path_requires_switch(*backing_file_out, backing_file, | |
723 | file); | |
724 | ||
725 | /* Allow switching only if no mismatch. */ | |
726 | if (asked_switch && !backing_file_mismatch(*backing_file_out, size, | |
727 | mtime)) { | |
728 | printk(KERN_ERR "Switching backing file to '%s'\n", | |
729 | *backing_file_out); | |
730 | err = write_cow_header(file, fd, *backing_file_out, | |
731 | sectorsize, align, &size); | |
732 | if (err) { | |
733 | printk(KERN_ERR "Switch failed, errno = %d\n", -err); | |
734 | goto out_close; | |
735 | } | |
736 | } else { | |
737 | *backing_file_out = backing_file; | |
738 | err = backing_file_mismatch(*backing_file_out, size, mtime); | |
739 | if (err) | |
740 | goto out_close; | |
741 | } | |
742 | ||
743 | cow_sizes(version, size, sectorsize, align, *bitmap_offset_out, | |
744 | bitmap_len_out, data_offset_out); | |
745 | ||
746 | return fd; | |
747 | out_close: | |
748 | os_close_file(fd); | |
749 | return err; | |
750 | } | |
751 | ||
752 | static int create_cow_file(char *cow_file, char *backing_file, | |
753 | struct openflags flags, | |
754 | int sectorsize, int alignment, int *bitmap_offset_out, | |
755 | unsigned long *bitmap_len_out, int *data_offset_out) | |
756 | { | |
757 | int err, fd; | |
758 | ||
759 | flags.c = 1; | |
760 | fd = open_ubd_file(cow_file, &flags, 0, NULL, NULL, NULL, NULL, NULL); | |
761 | if (fd < 0) { | |
762 | err = fd; | |
763 | printk(KERN_ERR "Open of COW file '%s' failed, errno = %d\n", | |
764 | cow_file, -err); | |
765 | goto out; | |
766 | } | |
767 | ||
768 | err = init_cow_file(fd, cow_file, backing_file, sectorsize, alignment, | |
769 | bitmap_offset_out, bitmap_len_out, | |
770 | data_offset_out); | |
771 | if (!err) | |
772 | return fd; | |
773 | os_close_file(fd); | |
774 | out: | |
775 | return err; | |
776 | } | |
777 | ||
5f75a4f8 | 778 | static void ubd_close_dev(struct ubd *ubd_dev) |
1da177e4 | 779 | { |
7d314e34 PBG |
780 | os_close_file(ubd_dev->fd); |
781 | if(ubd_dev->cow.file == NULL) | |
1da177e4 LT |
782 | return; |
783 | ||
7d314e34 PBG |
784 | os_close_file(ubd_dev->cow.fd); |
785 | vfree(ubd_dev->cow.bitmap); | |
786 | ubd_dev->cow.bitmap = NULL; | |
1da177e4 LT |
787 | } |
788 | ||
7d314e34 | 789 | static int ubd_open_dev(struct ubd *ubd_dev) |
1da177e4 LT |
790 | { |
791 | struct openflags flags; | |
792 | char **back_ptr; | |
793 | int err, create_cow, *create_ptr; | |
0bf16bff | 794 | int fd; |
1da177e4 | 795 | |
7d314e34 | 796 | ubd_dev->openflags = ubd_dev->boot_openflags; |
1da177e4 | 797 | create_cow = 0; |
7d314e34 PBG |
798 | create_ptr = (ubd_dev->cow.file != NULL) ? &create_cow : NULL; |
799 | back_ptr = ubd_dev->no_cow ? NULL : &ubd_dev->cow.file; | |
0bf16bff PBG |
800 | |
801 | fd = open_ubd_file(ubd_dev->file, &ubd_dev->openflags, ubd_dev->shared, | |
7d314e34 PBG |
802 | back_ptr, &ubd_dev->cow.bitmap_offset, |
803 | &ubd_dev->cow.bitmap_len, &ubd_dev->cow.data_offset, | |
6c29256c | 804 | create_ptr); |
1da177e4 | 805 | |
0bf16bff PBG |
806 | if((fd == -ENOENT) && create_cow){ |
807 | fd = create_cow_file(ubd_dev->file, ubd_dev->cow.file, | |
7d314e34 PBG |
808 | ubd_dev->openflags, 1 << 9, PAGE_SIZE, |
809 | &ubd_dev->cow.bitmap_offset, | |
810 | &ubd_dev->cow.bitmap_len, | |
811 | &ubd_dev->cow.data_offset); | |
0bf16bff | 812 | if(fd >= 0){ |
1da177e4 | 813 | printk(KERN_INFO "Creating \"%s\" as COW file for " |
7d314e34 | 814 | "\"%s\"\n", ubd_dev->file, ubd_dev->cow.file); |
1da177e4 LT |
815 | } |
816 | } | |
817 | ||
0bf16bff | 818 | if(fd < 0){ |
7d314e34 | 819 | printk("Failed to open '%s', errno = %d\n", ubd_dev->file, |
0bf16bff PBG |
820 | -fd); |
821 | return fd; | |
1da177e4 | 822 | } |
0bf16bff | 823 | ubd_dev->fd = fd; |
1da177e4 | 824 | |
7d314e34 | 825 | if(ubd_dev->cow.file != NULL){ |
086fa5ff | 826 | blk_queue_max_hw_sectors(ubd_dev->queue, 8 * sizeof(long)); |
f4768ffd | 827 | |
1da177e4 | 828 | err = -ENOMEM; |
da2486ba | 829 | ubd_dev->cow.bitmap = vmalloc(ubd_dev->cow.bitmap_len); |
7d314e34 | 830 | if(ubd_dev->cow.bitmap == NULL){ |
1da177e4 LT |
831 | printk(KERN_ERR "Failed to vmalloc COW bitmap\n"); |
832 | goto error; | |
833 | } | |
834 | flush_tlb_kernel_vm(); | |
835 | ||
7d314e34 PBG |
836 | err = read_cow_bitmap(ubd_dev->fd, ubd_dev->cow.bitmap, |
837 | ubd_dev->cow.bitmap_offset, | |
838 | ubd_dev->cow.bitmap_len); | |
1da177e4 LT |
839 | if(err < 0) |
840 | goto error; | |
841 | ||
7d314e34 | 842 | flags = ubd_dev->openflags; |
1da177e4 | 843 | flags.w = 0; |
7d314e34 | 844 | err = open_ubd_file(ubd_dev->cow.file, &flags, ubd_dev->shared, NULL, |
6c29256c | 845 | NULL, NULL, NULL, NULL); |
1da177e4 | 846 | if(err < 0) goto error; |
7d314e34 | 847 | ubd_dev->cow.fd = err; |
1da177e4 | 848 | } |
dc764e50 | 849 | return 0; |
1da177e4 | 850 | error: |
7d314e34 | 851 | os_close_file(ubd_dev->fd); |
dc764e50 | 852 | return err; |
1da177e4 LT |
853 | } |
854 | ||
2e3f5251 JD |
855 | static void ubd_device_release(struct device *dev) |
856 | { | |
8691b97b | 857 | struct ubd *ubd_dev = dev_get_drvdata(dev); |
2e3f5251 JD |
858 | |
859 | blk_cleanup_queue(ubd_dev->queue); | |
860 | *ubd_dev = ((struct ubd) DEFAULT_UBD); | |
861 | } | |
862 | ||
5f75a4f8 | 863 | static int ubd_disk_register(int major, u64 size, int unit, |
b8831a1d | 864 | struct gendisk **disk_out) |
1da177e4 | 865 | { |
d72a5783 | 866 | struct device *parent = NULL; |
1da177e4 | 867 | struct gendisk *disk; |
1da177e4 LT |
868 | |
869 | disk = alloc_disk(1 << UBD_SHIFT); | |
870 | if(disk == NULL) | |
dc764e50 | 871 | return -ENOMEM; |
1da177e4 LT |
872 | |
873 | disk->major = major; | |
874 | disk->first_minor = unit << UBD_SHIFT; | |
875 | disk->fops = &ubd_blops; | |
876 | set_capacity(disk, size / 512); | |
792dd4fc | 877 | if (major == UBD_MAJOR) |
1da177e4 | 878 | sprintf(disk->disk_name, "ubd%c", 'a' + unit); |
ce7b0f46 | 879 | else |
1da177e4 | 880 | sprintf(disk->disk_name, "ubd_fake%d", unit); |
1da177e4 LT |
881 | |
882 | /* sysfs register (not for ide fake devices) */ | |
792dd4fc | 883 | if (major == UBD_MAJOR) { |
7d314e34 PBG |
884 | ubd_devs[unit].pdev.id = unit; |
885 | ubd_devs[unit].pdev.name = DRIVER_NAME; | |
2e3f5251 | 886 | ubd_devs[unit].pdev.dev.release = ubd_device_release; |
8691b97b | 887 | dev_set_drvdata(&ubd_devs[unit].pdev.dev, &ubd_devs[unit]); |
7d314e34 | 888 | platform_device_register(&ubd_devs[unit].pdev); |
d72a5783 | 889 | parent = &ubd_devs[unit].pdev.dev; |
1da177e4 LT |
890 | } |
891 | ||
7d314e34 | 892 | disk->private_data = &ubd_devs[unit]; |
62f96cb0 | 893 | disk->queue = ubd_devs[unit].queue; |
d72a5783 | 894 | device_add_disk(parent, disk); |
1da177e4 LT |
895 | |
896 | *disk_out = disk; | |
897 | return 0; | |
898 | } | |
899 | ||
900 | #define ROUND_BLOCK(n) ((n + ((1 << 9) - 1)) & (-1 << 9)) | |
901 | ||
f28169d2 | 902 | static int ubd_add(int n, char **error_out) |
1da177e4 | 903 | { |
7d314e34 | 904 | struct ubd *ubd_dev = &ubd_devs[n]; |
f28169d2 | 905 | int err = 0; |
1da177e4 | 906 | |
7d314e34 | 907 | if(ubd_dev->file == NULL) |
ec7cf783 | 908 | goto out; |
1da177e4 | 909 | |
7d314e34 | 910 | err = ubd_file_size(ubd_dev, &ubd_dev->size); |
f28169d2 JD |
911 | if(err < 0){ |
912 | *error_out = "Couldn't determine size of device's file"; | |
80c13749 | 913 | goto out; |
f28169d2 | 914 | } |
1da177e4 | 915 | |
7d314e34 | 916 | ubd_dev->size = ROUND_BLOCK(ubd_dev->size); |
1da177e4 | 917 | |
a0044bdf | 918 | INIT_LIST_HEAD(&ubd_dev->restart); |
4f40c055 | 919 | sg_init_table(ubd_dev->sg, MAX_SG); |
a0044bdf | 920 | |
62f96cb0 JD |
921 | err = -ENOMEM; |
922 | ubd_dev->queue = blk_init_queue(do_ubd_request, &ubd_dev->lock); | |
923 | if (ubd_dev->queue == NULL) { | |
924 | *error_out = "Failed to initialize device queue"; | |
80c13749 | 925 | goto out; |
62f96cb0 JD |
926 | } |
927 | ubd_dev->queue->queuedata = ubd_dev; | |
f935a8ce | 928 | blk_queue_write_cache(ubd_dev->queue, true, false); |
62f96cb0 | 929 | |
8a78362c | 930 | blk_queue_max_segments(ubd_dev->queue, MAX_SG); |
792dd4fc | 931 | err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]); |
62f96cb0 JD |
932 | if(err){ |
933 | *error_out = "Failed to register device"; | |
934 | goto out_cleanup; | |
935 | } | |
6c29256c | 936 | |
792dd4fc | 937 | if (fake_major != UBD_MAJOR) |
5f75a4f8 | 938 | ubd_disk_register(fake_major, ubd_dev->size, n, |
62f96cb0 | 939 | &fake_gendisk[n]); |
1da177e4 | 940 | |
83380cc1 JD |
941 | /* |
942 | * Perhaps this should also be under the "if (fake_major)" above | |
943 | * using the fake_disk->disk_name | |
944 | */ | |
1da177e4 LT |
945 | if (fake_ide) |
946 | make_ide_entries(ubd_gendisk[n]->disk_name); | |
947 | ||
ec7cf783 | 948 | err = 0; |
ec7cf783 JD |
949 | out: |
950 | return err; | |
62f96cb0 JD |
951 | |
952 | out_cleanup: | |
953 | blk_cleanup_queue(ubd_dev->queue); | |
954 | goto out; | |
1da177e4 LT |
955 | } |
956 | ||
f28169d2 | 957 | static int ubd_config(char *str, char **error_out) |
1da177e4 | 958 | { |
e7f6552f | 959 | int n, ret; |
1da177e4 | 960 | |
f28169d2 JD |
961 | /* This string is possibly broken up and stored, so it's only |
962 | * freed if ubd_setup_common fails, or if only general options | |
963 | * were set. | |
964 | */ | |
970d6e3a | 965 | str = kstrdup(str, GFP_KERNEL); |
e7f6552f | 966 | if (str == NULL) { |
f28169d2 JD |
967 | *error_out = "Failed to allocate memory"; |
968 | return -ENOMEM; | |
1da177e4 | 969 | } |
f28169d2 JD |
970 | |
971 | ret = ubd_setup_common(str, &n, error_out); | |
972 | if (ret) | |
e7f6552f | 973 | goto err_free; |
f28169d2 | 974 | |
e7f6552f PBG |
975 | if (n == -1) { |
976 | ret = 0; | |
d8d7c28e | 977 | goto err_free; |
1da177e4 | 978 | } |
1da177e4 | 979 | |
dc764e50 | 980 | mutex_lock(&ubd_lock); |
f28169d2 | 981 | ret = ubd_add(n, error_out); |
e7f6552f | 982 | if (ret) |
7d314e34 | 983 | ubd_devs[n].file = NULL; |
dc764e50 | 984 | mutex_unlock(&ubd_lock); |
1da177e4 | 985 | |
e7f6552f | 986 | out: |
dc764e50 | 987 | return ret; |
e7f6552f PBG |
988 | |
989 | err_free: | |
990 | kfree(str); | |
991 | goto out; | |
1da177e4 LT |
992 | } |
993 | ||
994 | static int ubd_get_config(char *name, char *str, int size, char **error_out) | |
995 | { | |
7d314e34 | 996 | struct ubd *ubd_dev; |
1da177e4 LT |
997 | int n, len = 0; |
998 | ||
999 | n = parse_unit(&name); | |
1000 | if((n >= MAX_DEV) || (n < 0)){ | |
1001 | *error_out = "ubd_get_config : device number out of range"; | |
dc764e50 | 1002 | return -1; |
1da177e4 LT |
1003 | } |
1004 | ||
7d314e34 | 1005 | ubd_dev = &ubd_devs[n]; |
d7fb2c38 | 1006 | mutex_lock(&ubd_lock); |
1da177e4 | 1007 | |
7d314e34 | 1008 | if(ubd_dev->file == NULL){ |
1da177e4 LT |
1009 | CONFIG_CHUNK(str, size, len, "", 1); |
1010 | goto out; | |
1011 | } | |
1012 | ||
7d314e34 | 1013 | CONFIG_CHUNK(str, size, len, ubd_dev->file, 0); |
1da177e4 | 1014 | |
7d314e34 | 1015 | if(ubd_dev->cow.file != NULL){ |
1da177e4 | 1016 | CONFIG_CHUNK(str, size, len, ",", 0); |
7d314e34 | 1017 | CONFIG_CHUNK(str, size, len, ubd_dev->cow.file, 1); |
1da177e4 LT |
1018 | } |
1019 | else CONFIG_CHUNK(str, size, len, "", 1); | |
1020 | ||
1021 | out: | |
d7fb2c38 | 1022 | mutex_unlock(&ubd_lock); |
dc764e50 | 1023 | return len; |
1da177e4 LT |
1024 | } |
1025 | ||
29d56cfe JD |
1026 | static int ubd_id(char **str, int *start_out, int *end_out) |
1027 | { | |
dc764e50 | 1028 | int n; |
29d56cfe JD |
1029 | |
1030 | n = parse_unit(str); | |
dc764e50 JD |
1031 | *start_out = 0; |
1032 | *end_out = MAX_DEV - 1; | |
1033 | return n; | |
29d56cfe JD |
1034 | } |
1035 | ||
f28169d2 | 1036 | static int ubd_remove(int n, char **error_out) |
1da177e4 | 1037 | { |
2e3f5251 | 1038 | struct gendisk *disk = ubd_gendisk[n]; |
7d314e34 | 1039 | struct ubd *ubd_dev; |
29d56cfe | 1040 | int err = -ENODEV; |
1da177e4 | 1041 | |
d7fb2c38 | 1042 | mutex_lock(&ubd_lock); |
1da177e4 | 1043 | |
7d314e34 | 1044 | ubd_dev = &ubd_devs[n]; |
1da177e4 | 1045 | |
7d314e34 | 1046 | if(ubd_dev->file == NULL) |
29d56cfe | 1047 | goto out; |
1da177e4 | 1048 | |
29d56cfe JD |
1049 | /* you cannot remove a open disk */ |
1050 | err = -EBUSY; | |
7d314e34 | 1051 | if(ubd_dev->count > 0) |
1da177e4 LT |
1052 | goto out; |
1053 | ||
dc764e50 | 1054 | ubd_gendisk[n] = NULL; |
b47d2deb JD |
1055 | if(disk != NULL){ |
1056 | del_gendisk(disk); | |
1057 | put_disk(disk); | |
1058 | } | |
1da177e4 LT |
1059 | |
1060 | if(fake_gendisk[n] != NULL){ | |
1061 | del_gendisk(fake_gendisk[n]); | |
1062 | put_disk(fake_gendisk[n]); | |
1063 | fake_gendisk[n] = NULL; | |
1064 | } | |
1065 | ||
1da177e4 | 1066 | err = 0; |
2e3f5251 | 1067 | platform_device_unregister(&ubd_dev->pdev); |
29d56cfe | 1068 | out: |
d7fb2c38 | 1069 | mutex_unlock(&ubd_lock); |
29d56cfe | 1070 | return err; |
1da177e4 LT |
1071 | } |
1072 | ||
f28169d2 | 1073 | /* All these are called by mconsole in process context and without |
b8831a1d | 1074 | * ubd-specific locks. The structure itself is const except for .list. |
f28169d2 | 1075 | */ |
1da177e4 | 1076 | static struct mc_device ubd_mc = { |
84f48d4f | 1077 | .list = LIST_HEAD_INIT(ubd_mc.list), |
1da177e4 LT |
1078 | .name = "ubd", |
1079 | .config = ubd_config, | |
dc764e50 | 1080 | .get_config = ubd_get_config, |
29d56cfe | 1081 | .id = ubd_id, |
1da177e4 LT |
1082 | .remove = ubd_remove, |
1083 | }; | |
1084 | ||
d8d7c28e | 1085 | static int __init ubd_mc_init(void) |
1da177e4 LT |
1086 | { |
1087 | mconsole_register_dev(&ubd_mc); | |
1088 | return 0; | |
1089 | } | |
1090 | ||
1091 | __initcall(ubd_mc_init); | |
1092 | ||
d8d7c28e PBG |
1093 | static int __init ubd0_init(void) |
1094 | { | |
1095 | struct ubd *ubd_dev = &ubd_devs[0]; | |
1096 | ||
b8831a1d | 1097 | mutex_lock(&ubd_lock); |
d8d7c28e PBG |
1098 | if(ubd_dev->file == NULL) |
1099 | ubd_dev->file = "root_fs"; | |
b8831a1d JD |
1100 | mutex_unlock(&ubd_lock); |
1101 | ||
dc764e50 | 1102 | return 0; |
d8d7c28e PBG |
1103 | } |
1104 | ||
1105 | __initcall(ubd0_init); | |
1106 | ||
b8831a1d | 1107 | /* Used in ubd_init, which is an initcall */ |
3ae5eaec RK |
1108 | static struct platform_driver ubd_driver = { |
1109 | .driver = { | |
1110 | .name = DRIVER_NAME, | |
1111 | }, | |
1da177e4 LT |
1112 | }; |
1113 | ||
d8d7c28e | 1114 | static int __init ubd_init(void) |
1da177e4 | 1115 | { |
f28169d2 JD |
1116 | char *error; |
1117 | int i, err; | |
1da177e4 | 1118 | |
792dd4fc | 1119 | if (register_blkdev(UBD_MAJOR, "ubd")) |
1da177e4 LT |
1120 | return -1; |
1121 | ||
792dd4fc | 1122 | if (fake_major != UBD_MAJOR) { |
1da177e4 LT |
1123 | char name[sizeof("ubd_nnn\0")]; |
1124 | ||
1125 | snprintf(name, sizeof(name), "ubd_%d", fake_major); | |
1da177e4 LT |
1126 | if (register_blkdev(fake_major, "ubd")) |
1127 | return -1; | |
1128 | } | |
f88f0bdf | 1129 | |
6da2ec56 KC |
1130 | irq_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, |
1131 | sizeof(struct io_thread_req *), | |
1132 | GFP_KERNEL | |
f88f0bdf AI |
1133 | ); |
1134 | irq_remainder = 0; | |
1135 | ||
1136 | if (irq_req_buffer == NULL) { | |
1137 | printk(KERN_ERR "Failed to initialize ubd buffering\n"); | |
1138 | return -1; | |
1139 | } | |
6da2ec56 KC |
1140 | io_req_buffer = kmalloc_array(UBD_REQ_BUFFER_SIZE, |
1141 | sizeof(struct io_thread_req *), | |
1142 | GFP_KERNEL | |
f88f0bdf AI |
1143 | ); |
1144 | ||
1145 | io_remainder = 0; | |
1146 | ||
1147 | if (io_req_buffer == NULL) { | |
1148 | printk(KERN_ERR "Failed to initialize ubd buffering\n"); | |
1149 | return -1; | |
1150 | } | |
3ae5eaec | 1151 | platform_driver_register(&ubd_driver); |
dc764e50 | 1152 | mutex_lock(&ubd_lock); |
f28169d2 JD |
1153 | for (i = 0; i < MAX_DEV; i++){ |
1154 | err = ubd_add(i, &error); | |
1155 | if(err) | |
1156 | printk(KERN_ERR "Failed to initialize ubd device %d :" | |
1157 | "%s\n", i, error); | |
1158 | } | |
dc764e50 | 1159 | mutex_unlock(&ubd_lock); |
1da177e4 LT |
1160 | return 0; |
1161 | } | |
1162 | ||
1163 | late_initcall(ubd_init); | |
1164 | ||
d8d7c28e | 1165 | static int __init ubd_driver_init(void){ |
91acb21f JD |
1166 | unsigned long stack; |
1167 | int err; | |
1168 | ||
1169 | /* Set by CONFIG_BLK_DEV_UBD_SYNC or ubd=sync.*/ | |
1170 | if(global_openflags.s){ | |
1171 | printk(KERN_INFO "ubd: Synchronous mode\n"); | |
1172 | /* Letting ubd=sync be like using ubd#s= instead of ubd#= is | |
1173 | * enough. So use anyway the io thread. */ | |
1174 | } | |
1175 | stack = alloc_stack(0, 0); | |
6c29256c | 1176 | io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), |
91acb21f JD |
1177 | &thread_fd); |
1178 | if(io_pid < 0){ | |
6c29256c | 1179 | printk(KERN_ERR |
91acb21f JD |
1180 | "ubd : Failed to start I/O thread (errno = %d) - " |
1181 | "falling back to synchronous I/O\n", -io_pid); | |
1182 | io_pid = -1; | |
dc764e50 | 1183 | return 0; |
91acb21f | 1184 | } |
6c29256c | 1185 | err = um_request_irq(UBD_IRQ, thread_fd, IRQ_READ, ubd_intr, |
c0b79a90 | 1186 | 0, "ubd", ubd_devs); |
91acb21f JD |
1187 | if(err != 0) |
1188 | printk(KERN_ERR "um_request_irq failed - errno = %d\n", -err); | |
f4c57a78 | 1189 | return 0; |
91acb21f JD |
1190 | } |
1191 | ||
1192 | device_initcall(ubd_driver_init); | |
1193 | ||
a625c998 | 1194 | static int ubd_open(struct block_device *bdev, fmode_t mode) |
1da177e4 | 1195 | { |
a625c998 | 1196 | struct gendisk *disk = bdev->bd_disk; |
7d314e34 | 1197 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 LT |
1198 | int err = 0; |
1199 | ||
9a181c58 | 1200 | mutex_lock(&ubd_mutex); |
7d314e34 PBG |
1201 | if(ubd_dev->count == 0){ |
1202 | err = ubd_open_dev(ubd_dev); | |
1da177e4 LT |
1203 | if(err){ |
1204 | printk(KERN_ERR "%s: Can't open \"%s\": errno = %d\n", | |
7d314e34 | 1205 | disk->disk_name, ubd_dev->file, -err); |
1da177e4 LT |
1206 | goto out; |
1207 | } | |
1208 | } | |
7d314e34 PBG |
1209 | ubd_dev->count++; |
1210 | set_disk_ro(disk, !ubd_dev->openflags.w); | |
2c49be99 PBG |
1211 | |
1212 | /* This should no more be needed. And it didn't work anyway to exclude | |
1213 | * read-write remounting of filesystems.*/ | |
a625c998 | 1214 | /*if((mode & FMODE_WRITE) && !ubd_dev->openflags.w){ |
5f75a4f8 | 1215 | if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev); |
1da177e4 | 1216 | err = -EROFS; |
2c49be99 | 1217 | }*/ |
6e9624b8 | 1218 | out: |
9a181c58 | 1219 | mutex_unlock(&ubd_mutex); |
dc764e50 | 1220 | return err; |
1da177e4 LT |
1221 | } |
1222 | ||
db2a144b | 1223 | static void ubd_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 1224 | { |
7d314e34 | 1225 | struct ubd *ubd_dev = disk->private_data; |
1da177e4 | 1226 | |
9a181c58 | 1227 | mutex_lock(&ubd_mutex); |
7d314e34 | 1228 | if(--ubd_dev->count == 0) |
5f75a4f8 | 1229 | ubd_close_dev(ubd_dev); |
9a181c58 | 1230 | mutex_unlock(&ubd_mutex); |
1da177e4 LT |
1231 | } |
1232 | ||
91acb21f JD |
1233 | static void cowify_bitmap(__u64 io_offset, int length, unsigned long *cow_mask, |
1234 | __u64 *cow_offset, unsigned long *bitmap, | |
1235 | __u64 bitmap_offset, unsigned long *bitmap_words, | |
1236 | __u64 bitmap_len) | |
1da177e4 | 1237 | { |
91acb21f JD |
1238 | __u64 sector = io_offset >> 9; |
1239 | int i, update_bitmap = 0; | |
1240 | ||
1241 | for(i = 0; i < length >> 9; i++){ | |
1242 | if(cow_mask != NULL) | |
1243 | ubd_set_bit(i, (unsigned char *) cow_mask); | |
1244 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
1245 | continue; | |
1da177e4 | 1246 | |
91acb21f JD |
1247 | update_bitmap = 1; |
1248 | ubd_set_bit(sector + i, (unsigned char *) bitmap); | |
1249 | } | |
1250 | ||
1251 | if(!update_bitmap) | |
1252 | return; | |
1da177e4 | 1253 | |
91acb21f | 1254 | *cow_offset = sector / (sizeof(unsigned long) * 8); |
1da177e4 | 1255 | |
91acb21f JD |
1256 | /* This takes care of the case where we're exactly at the end of the |
1257 | * device, and *cow_offset + 1 is off the end. So, just back it up | |
1258 | * by one word. Thanks to Lynn Kerby for the fix and James McMechan | |
1259 | * for the original diagnosis. | |
1260 | */ | |
6d074242 JO |
1261 | if (*cow_offset == (DIV_ROUND_UP(bitmap_len, |
1262 | sizeof(unsigned long)) - 1)) | |
91acb21f JD |
1263 | (*cow_offset)--; |
1264 | ||
1265 | bitmap_words[0] = bitmap[*cow_offset]; | |
1266 | bitmap_words[1] = bitmap[*cow_offset + 1]; | |
1267 | ||
1268 | *cow_offset *= sizeof(unsigned long); | |
1269 | *cow_offset += bitmap_offset; | |
1270 | } | |
1271 | ||
1272 | static void cowify_req(struct io_thread_req *req, unsigned long *bitmap, | |
1273 | __u64 bitmap_offset, __u64 bitmap_len) | |
1274 | { | |
1275 | __u64 sector = req->offset >> 9; | |
1276 | int i; | |
1277 | ||
1278 | if(req->length > (sizeof(req->sector_mask) * 8) << 9) | |
1279 | panic("Operation too long"); | |
1280 | ||
1281 | if(req->op == UBD_READ) { | |
1282 | for(i = 0; i < req->length >> 9; i++){ | |
1283 | if(ubd_test_bit(sector + i, (unsigned char *) bitmap)) | |
6c29256c | 1284 | ubd_set_bit(i, (unsigned char *) |
91acb21f | 1285 | &req->sector_mask); |
dc764e50 | 1286 | } |
91acb21f JD |
1287 | } |
1288 | else cowify_bitmap(req->offset, req->length, &req->sector_mask, | |
1289 | &req->cow_offset, bitmap, bitmap_offset, | |
1290 | req->bitmap_words, bitmap_len); | |
1da177e4 LT |
1291 | } |
1292 | ||
62f96cb0 | 1293 | /* Called with dev->lock held */ |
a0044bdf JD |
1294 | static void prepare_request(struct request *req, struct io_thread_req *io_req, |
1295 | unsigned long long offset, int page_offset, | |
1296 | int len, struct page *page) | |
1da177e4 LT |
1297 | { |
1298 | struct gendisk *disk = req->rq_disk; | |
7d314e34 | 1299 | struct ubd *ubd_dev = disk->private_data; |
91acb21f | 1300 | |
62f96cb0 | 1301 | io_req->req = req; |
a0044bdf JD |
1302 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : |
1303 | ubd_dev->fd; | |
7d314e34 | 1304 | io_req->fds[1] = ubd_dev->fd; |
91acb21f | 1305 | io_req->cow_offset = -1; |
1da177e4 LT |
1306 | io_req->offset = offset; |
1307 | io_req->length = len; | |
1308 | io_req->error = 0; | |
91acb21f JD |
1309 | io_req->sector_mask = 0; |
1310 | ||
1311 | io_req->op = (rq_data_dir(req) == READ) ? UBD_READ : UBD_WRITE; | |
1da177e4 | 1312 | io_req->offsets[0] = 0; |
7d314e34 | 1313 | io_req->offsets[1] = ubd_dev->cow.data_offset; |
a0044bdf | 1314 | io_req->buffer = page_address(page) + page_offset; |
1da177e4 LT |
1315 | io_req->sectorsize = 1 << 9; |
1316 | ||
7d314e34 | 1317 | if(ubd_dev->cow.file != NULL) |
a0044bdf JD |
1318 | cowify_req(io_req, ubd_dev->cow.bitmap, |
1319 | ubd_dev->cow.bitmap_offset, ubd_dev->cow.bitmap_len); | |
91acb21f | 1320 | |
1da177e4 LT |
1321 | } |
1322 | ||
805f11a0 RW |
1323 | /* Called with dev->lock held */ |
1324 | static void prepare_flush_request(struct request *req, | |
1325 | struct io_thread_req *io_req) | |
1326 | { | |
1327 | struct gendisk *disk = req->rq_disk; | |
1328 | struct ubd *ubd_dev = disk->private_data; | |
1329 | ||
1330 | io_req->req = req; | |
1331 | io_req->fds[0] = (ubd_dev->cow.file != NULL) ? ubd_dev->cow.fd : | |
1332 | ubd_dev->fd; | |
1333 | io_req->op = UBD_FLUSH; | |
1334 | } | |
1335 | ||
bc1d72e7 RW |
1336 | static bool submit_request(struct io_thread_req *io_req, struct ubd *dev) |
1337 | { | |
1338 | int n = os_write_file(thread_fd, &io_req, | |
1339 | sizeof(io_req)); | |
1340 | if (n != sizeof(io_req)) { | |
1341 | if (n != -EAGAIN) | |
1342 | printk("write to io thread failed, " | |
1343 | "errno = %d\n", -n); | |
1344 | else if (list_empty(&dev->restart)) | |
1345 | list_add(&dev->restart, &restart); | |
1346 | ||
1347 | kfree(io_req); | |
1348 | return false; | |
1349 | } | |
1350 | return true; | |
1351 | } | |
1352 | ||
62f96cb0 | 1353 | /* Called with dev->lock held */ |
165125e1 | 1354 | static void do_ubd_request(struct request_queue *q) |
1da177e4 | 1355 | { |
2adcec21 | 1356 | struct io_thread_req *io_req; |
1da177e4 | 1357 | struct request *req; |
a0044bdf JD |
1358 | |
1359 | while(1){ | |
2a9529a0 | 1360 | struct ubd *dev = q->queuedata; |
2a236122 | 1361 | if(dev->request == NULL){ |
9934c8c0 | 1362 | struct request *req = blk_fetch_request(q); |
a0044bdf JD |
1363 | if(req == NULL) |
1364 | return; | |
1365 | ||
1366 | dev->request = req; | |
47526903 | 1367 | dev->rq_pos = blk_rq_pos(req); |
a0044bdf JD |
1368 | dev->start_sg = 0; |
1369 | dev->end_sg = blk_rq_map_sg(q, req, dev->sg); | |
1370 | } | |
1371 | ||
1372 | req = dev->request; | |
805f11a0 | 1373 | |
3a5e02ce | 1374 | if (req_op(req) == REQ_OP_FLUSH) { |
805f11a0 RW |
1375 | io_req = kmalloc(sizeof(struct io_thread_req), |
1376 | GFP_ATOMIC); | |
1377 | if (io_req == NULL) { | |
1378 | if (list_empty(&dev->restart)) | |
1379 | list_add(&dev->restart, &restart); | |
1380 | return; | |
1381 | } | |
1382 | prepare_flush_request(req, io_req); | |
2a236122 TK |
1383 | if (submit_request(io_req, dev) == false) |
1384 | return; | |
805f11a0 RW |
1385 | } |
1386 | ||
a0044bdf JD |
1387 | while(dev->start_sg < dev->end_sg){ |
1388 | struct scatterlist *sg = &dev->sg[dev->start_sg]; | |
1389 | ||
2adcec21 | 1390 | io_req = kmalloc(sizeof(struct io_thread_req), |
990c5587 | 1391 | GFP_ATOMIC); |
2adcec21 JD |
1392 | if(io_req == NULL){ |
1393 | if(list_empty(&dev->restart)) | |
1394 | list_add(&dev->restart, &restart); | |
1395 | return; | |
1396 | } | |
1397 | prepare_request(req, io_req, | |
47526903 | 1398 | (unsigned long long)dev->rq_pos << 9, |
45711f1a | 1399 | sg->offset, sg->length, sg_page(sg)); |
a0044bdf | 1400 | |
bc1d72e7 | 1401 | if (submit_request(io_req, dev) == false) |
a0044bdf | 1402 | return; |
a0044bdf | 1403 | |
47526903 | 1404 | dev->rq_pos += sg->length >> 9; |
a0044bdf | 1405 | dev->start_sg++; |
1da177e4 | 1406 | } |
a0044bdf JD |
1407 | dev->end_sg = 0; |
1408 | dev->request = NULL; | |
1da177e4 LT |
1409 | } |
1410 | } | |
1411 | ||
a885c8c4 CH |
1412 | static int ubd_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
1413 | { | |
7d314e34 | 1414 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
a885c8c4 CH |
1415 | |
1416 | geo->heads = 128; | |
1417 | geo->sectors = 32; | |
7d314e34 | 1418 | geo->cylinders = ubd_dev->size / (128 * 32 * 512); |
a885c8c4 CH |
1419 | return 0; |
1420 | } | |
1421 | ||
a625c998 | 1422 | static int ubd_ioctl(struct block_device *bdev, fmode_t mode, |
1da177e4 LT |
1423 | unsigned int cmd, unsigned long arg) |
1424 | { | |
a625c998 | 1425 | struct ubd *ubd_dev = bdev->bd_disk->private_data; |
73855e13 | 1426 | u16 ubd_id[ATA_ID_WORDS]; |
1da177e4 LT |
1427 | |
1428 | switch (cmd) { | |
1da177e4 | 1429 | struct cdrom_volctrl volume; |
1da177e4 | 1430 | case HDIO_GET_IDENTITY: |
73855e13 BZ |
1431 | memset(&ubd_id, 0, ATA_ID_WORDS * 2); |
1432 | ubd_id[ATA_ID_CYLS] = ubd_dev->size / (128 * 32 * 512); | |
1433 | ubd_id[ATA_ID_HEADS] = 128; | |
1434 | ubd_id[ATA_ID_SECTORS] = 32; | |
1da177e4 LT |
1435 | if(copy_to_user((char __user *) arg, (char *) &ubd_id, |
1436 | sizeof(ubd_id))) | |
dc764e50 JD |
1437 | return -EFAULT; |
1438 | return 0; | |
b8831a1d | 1439 | |
1da177e4 LT |
1440 | case CDROMVOLREAD: |
1441 | if(copy_from_user(&volume, (char __user *) arg, sizeof(volume))) | |
dc764e50 | 1442 | return -EFAULT; |
1da177e4 LT |
1443 | volume.channel0 = 255; |
1444 | volume.channel1 = 255; | |
1445 | volume.channel2 = 255; | |
1446 | volume.channel3 = 255; | |
1447 | if(copy_to_user((char __user *) arg, &volume, sizeof(volume))) | |
dc764e50 JD |
1448 | return -EFAULT; |
1449 | return 0; | |
1da177e4 | 1450 | } |
dc764e50 | 1451 | return -EINVAL; |
1da177e4 LT |
1452 | } |
1453 | ||
91acb21f | 1454 | static int update_bitmap(struct io_thread_req *req) |
1da177e4 | 1455 | { |
91acb21f | 1456 | int n; |
1da177e4 | 1457 | |
91acb21f | 1458 | if(req->cow_offset == -1) |
dc764e50 | 1459 | return 0; |
1da177e4 | 1460 | |
8c6157b6 AI |
1461 | n = os_pwrite_file(req->fds[1], &req->bitmap_words, |
1462 | sizeof(req->bitmap_words), req->cow_offset); | |
91acb21f JD |
1463 | if(n != sizeof(req->bitmap_words)){ |
1464 | printk("do_io - bitmap update failed, err = %d fd = %d\n", -n, | |
1465 | req->fds[1]); | |
dc764e50 | 1466 | return 1; |
91acb21f | 1467 | } |
1da177e4 | 1468 | |
dc764e50 | 1469 | return 0; |
91acb21f | 1470 | } |
1da177e4 | 1471 | |
5dc62b1b | 1472 | static void do_io(struct io_thread_req *req) |
91acb21f JD |
1473 | { |
1474 | char *buf; | |
1475 | unsigned long len; | |
1476 | int n, nsectors, start, end, bit; | |
91acb21f JD |
1477 | __u64 off; |
1478 | ||
805f11a0 RW |
1479 | if (req->op == UBD_FLUSH) { |
1480 | /* fds[0] is always either the rw image or our cow file */ | |
1481 | n = os_sync_file(req->fds[0]); | |
1482 | if (n != 0) { | |
1483 | printk("do_io - sync failed err = %d " | |
1484 | "fd = %d\n", -n, req->fds[0]); | |
1485 | req->error = 1; | |
1486 | } | |
1487 | return; | |
1488 | } | |
1489 | ||
91acb21f JD |
1490 | nsectors = req->length / req->sectorsize; |
1491 | start = 0; | |
1492 | do { | |
1493 | bit = ubd_test_bit(start, (unsigned char *) &req->sector_mask); | |
1494 | end = start; | |
1495 | while((end < nsectors) && | |
1496 | (ubd_test_bit(end, (unsigned char *) | |
1497 | &req->sector_mask) == bit)) | |
1498 | end++; | |
1499 | ||
1500 | off = req->offset + req->offsets[bit] + | |
1501 | start * req->sectorsize; | |
1502 | len = (end - start) * req->sectorsize; | |
1503 | buf = &req->buffer[start * req->sectorsize]; | |
1504 | ||
91acb21f JD |
1505 | if(req->op == UBD_READ){ |
1506 | n = 0; | |
1507 | do { | |
1508 | buf = &buf[n]; | |
1509 | len -= n; | |
8c6157b6 | 1510 | n = os_pread_file(req->fds[bit], buf, len, off); |
91acb21f JD |
1511 | if (n < 0) { |
1512 | printk("do_io - read failed, err = %d " | |
1513 | "fd = %d\n", -n, req->fds[bit]); | |
1514 | req->error = 1; | |
1515 | return; | |
1516 | } | |
1517 | } while((n < len) && (n != 0)); | |
1518 | if (n < len) memset(&buf[n], 0, len - n); | |
1519 | } else { | |
8c6157b6 | 1520 | n = os_pwrite_file(req->fds[bit], buf, len, off); |
91acb21f JD |
1521 | if(n != len){ |
1522 | printk("do_io - write failed err = %d " | |
1523 | "fd = %d\n", -n, req->fds[bit]); | |
1524 | req->error = 1; | |
1525 | return; | |
1526 | } | |
1527 | } | |
1528 | ||
1529 | start = end; | |
1530 | } while(start < nsectors); | |
1da177e4 | 1531 | |
91acb21f | 1532 | req->error = update_bitmap(req); |
1da177e4 | 1533 | } |
91acb21f JD |
1534 | |
1535 | /* Changed in start_io_thread, which is serialized by being called only | |
1536 | * from ubd_init, which is an initcall. | |
1537 | */ | |
1538 | int kernel_fd = -1; | |
1539 | ||
d8d7c28e PBG |
1540 | /* Only changed by the io thread. XXX: currently unused. */ |
1541 | static int io_count = 0; | |
91acb21f JD |
1542 | |
1543 | int io_thread(void *arg) | |
1544 | { | |
f88f0bdf | 1545 | int n, count, written, res; |
91acb21f | 1546 | |
91d44ff8 RW |
1547 | os_fix_helper_signals(); |
1548 | ||
91acb21f | 1549 | while(1){ |
f88f0bdf AI |
1550 | n = bulk_req_safe_read( |
1551 | kernel_fd, | |
1552 | io_req_buffer, | |
1553 | &io_remainder, | |
1554 | &io_remainder_size, | |
1555 | UBD_REQ_BUFFER_SIZE | |
1556 | ); | |
1557 | if (n < 0) { | |
1558 | if (n == -EAGAIN) { | |
1559 | ubd_read_poll(-1); | |
1560 | continue; | |
1561 | } else { | |
91acb21f | 1562 | printk("io_thread - read failed, fd = %d, " |
f88f0bdf AI |
1563 | "err = %d," |
1564 | "reminder = %d\n", | |
1565 | kernel_fd, -n, io_remainder_size); | |
91acb21f | 1566 | } |
91acb21f | 1567 | } |
f88f0bdf AI |
1568 | |
1569 | for (count = 0; count < n/sizeof(struct io_thread_req *); count++) { | |
1570 | io_count++; | |
1571 | do_io((*io_req_buffer)[count]); | |
1572 | } | |
1573 | ||
1574 | written = 0; | |
1575 | ||
1576 | do { | |
1577 | res = os_write_file(kernel_fd, ((char *) io_req_buffer) + written, n); | |
ff6a1798 | 1578 | if (res >= 0) { |
f88f0bdf AI |
1579 | written += res; |
1580 | } else { | |
1581 | if (res != -EAGAIN) { | |
ff6a1798 | 1582 | printk("io_thread - write failed, fd = %d, " |
f88f0bdf AI |
1583 | "err = %d\n", kernel_fd, -n); |
1584 | } | |
1585 | } | |
1586 | if (written < n) { | |
1587 | ubd_write_poll(-1); | |
1588 | } | |
1589 | } while (written < n); | |
91acb21f | 1590 | } |
91acb21f | 1591 | |
1b57e9c2 JD |
1592 | return 0; |
1593 | } |