Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * dcssblk.c -- the S/390 block driver for dcss memory |
| 3 | * |
| 4 | * Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer |
| 5 | */ |
| 6 | |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 7 | #define KMSG_COMPONENT "dcssblk" |
| 8 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
| 9 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
| 11 | #include <linux/moduleparam.h> |
| 12 | #include <linux/ctype.h> |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/blkdev.h> |
| 17 | #include <asm/extmem.h> |
| 18 | #include <asm/io.h> |
| 19 | #include <linux/completion.h> |
| 20 | #include <linux/interrupt.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | #define DCSSBLK_NAME "dcssblk" |
| 23 | #define DCSSBLK_MINORS_PER_DISK 1 |
| 24 | #define DCSSBLK_PARM_LEN 400 |
Kay Sievers | 98df67b | 2008-12-25 13:38:55 +0100 | [diff] [blame] | 25 | #define DCSS_BUS_ID_SIZE 20 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 27 | static int dcssblk_open(struct block_device *bdev, fmode_t mode); |
| 28 | static int dcssblk_release(struct gendisk *disk, fmode_t mode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | static int dcssblk_make_request(struct request_queue *q, struct bio *bio); |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 30 | static int dcssblk_direct_access(struct block_device *bdev, sector_t secnum, |
Jared Hulbert | 30afcb4 | 2008-04-28 02:13:02 -0700 | [diff] [blame] | 31 | void **kaddr, unsigned long *pfn); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | |
| 33 | static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; |
| 34 | |
| 35 | static int dcssblk_major; |
| 36 | static struct block_device_operations dcssblk_devops = { |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 37 | .owner = THIS_MODULE, |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 38 | .open = dcssblk_open, |
| 39 | .release = dcssblk_release, |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 40 | .direct_access = dcssblk_direct_access, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | }; |
| 42 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | struct dcssblk_dev_info { |
| 44 | struct list_head lh; |
| 45 | struct device dev; |
Kay Sievers | 98df67b | 2008-12-25 13:38:55 +0100 | [diff] [blame] | 46 | char segment_name[DCSS_BUS_ID_SIZE]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | atomic_t use_count; |
| 48 | struct gendisk *gd; |
| 49 | unsigned long start; |
| 50 | unsigned long end; |
| 51 | int segment_type; |
| 52 | unsigned char save_pending; |
| 53 | unsigned char is_shared; |
| 54 | struct request_queue *dcssblk_queue; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 55 | int num_of_segments; |
| 56 | struct list_head seg_list; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | }; |
| 58 | |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 59 | struct segment_info { |
| 60 | struct list_head lh; |
Kay Sievers | 98df67b | 2008-12-25 13:38:55 +0100 | [diff] [blame] | 61 | char segment_name[DCSS_BUS_ID_SIZE]; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 62 | unsigned long start; |
| 63 | unsigned long end; |
| 64 | int segment_type; |
| 65 | }; |
| 66 | |
| 67 | static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf, |
| 68 | size_t count); |
| 69 | static ssize_t dcssblk_remove_store(struct device * dev, struct device_attribute *attr, const char * buf, |
| 70 | size_t count); |
| 71 | static ssize_t dcssblk_save_store(struct device * dev, struct device_attribute *attr, const char * buf, |
| 72 | size_t count); |
| 73 | static ssize_t dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf); |
| 74 | static ssize_t dcssblk_shared_store(struct device * dev, struct device_attribute *attr, const char * buf, |
| 75 | size_t count); |
| 76 | static ssize_t dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf); |
| 77 | static ssize_t dcssblk_seglist_show(struct device *dev, |
| 78 | struct device_attribute *attr, |
| 79 | char *buf); |
| 80 | |
| 81 | static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store); |
| 82 | static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store); |
| 83 | static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show, |
| 84 | dcssblk_save_store); |
| 85 | static DEVICE_ATTR(shared, S_IWUSR | S_IRUSR, dcssblk_shared_show, |
| 86 | dcssblk_shared_store); |
| 87 | static DEVICE_ATTR(seglist, S_IRUSR, dcssblk_seglist_show, NULL); |
| 88 | |
| 89 | static struct device *dcssblk_root_dev; |
| 90 | |
Denis Cheng | c11ca97 | 2008-01-26 14:11:13 +0100 | [diff] [blame] | 91 | static LIST_HEAD(dcssblk_devices); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | static struct rw_semaphore dcssblk_devices_sem; |
| 93 | |
| 94 | /* |
| 95 | * release function for segment device. |
| 96 | */ |
| 97 | static void |
| 98 | dcssblk_release_segment(struct device *dev) |
| 99 | { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 100 | struct dcssblk_dev_info *dev_info; |
| 101 | struct segment_info *entry, *temp; |
| 102 | |
| 103 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 104 | list_for_each_entry_safe(entry, temp, &dev_info->seg_list, lh) { |
| 105 | list_del(&entry->lh); |
| 106 | kfree(entry); |
| 107 | } |
| 108 | kfree(dev_info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | module_put(THIS_MODULE); |
| 110 | } |
| 111 | |
| 112 | /* |
| 113 | * get a minor number. needs to be called with |
| 114 | * down_write(&dcssblk_devices_sem) and the |
| 115 | * device needs to be enqueued before the semaphore is |
| 116 | * freed. |
| 117 | */ |
Heiko Carstens | 4d284ca | 2007-02-05 21:18:53 +0100 | [diff] [blame] | 118 | static int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info) |
| 120 | { |
| 121 | int minor, found; |
| 122 | struct dcssblk_dev_info *entry; |
| 123 | |
| 124 | if (dev_info == NULL) |
| 125 | return -EINVAL; |
| 126 | for (minor = 0; minor < (1<<MINORBITS); minor++) { |
| 127 | found = 0; |
| 128 | // test if minor available |
| 129 | list_for_each_entry(entry, &dcssblk_devices, lh) |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 130 | if (minor == MINOR(disk_devt(entry->gd))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | found++; |
| 132 | if (!found) break; // got unused minor |
| 133 | } |
| 134 | if (found) |
| 135 | return -EBUSY; |
| 136 | dev_info->gd->first_minor = minor; |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * get the struct dcssblk_dev_info from dcssblk_devices |
| 142 | * for the given name. |
| 143 | * down_read(&dcssblk_devices_sem) must be held. |
| 144 | */ |
| 145 | static struct dcssblk_dev_info * |
| 146 | dcssblk_get_device_by_name(char *name) |
| 147 | { |
| 148 | struct dcssblk_dev_info *entry; |
| 149 | |
| 150 | list_for_each_entry(entry, &dcssblk_devices, lh) { |
| 151 | if (!strcmp(name, entry->segment_name)) { |
| 152 | return entry; |
| 153 | } |
| 154 | } |
| 155 | return NULL; |
| 156 | } |
| 157 | |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 158 | /* |
| 159 | * get the struct segment_info from seg_list |
| 160 | * for the given name. |
| 161 | * down_read(&dcssblk_devices_sem) must be held. |
| 162 | */ |
| 163 | static struct segment_info * |
| 164 | dcssblk_get_segment_by_name(char *name) |
| 165 | { |
| 166 | struct dcssblk_dev_info *dev_info; |
| 167 | struct segment_info *entry; |
| 168 | |
| 169 | list_for_each_entry(dev_info, &dcssblk_devices, lh) { |
| 170 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 171 | if (!strcmp(name, entry->segment_name)) |
| 172 | return entry; |
| 173 | } |
| 174 | } |
| 175 | return NULL; |
| 176 | } |
| 177 | |
| 178 | /* |
| 179 | * get the highest address of the multi-segment block. |
| 180 | */ |
| 181 | static unsigned long |
| 182 | dcssblk_find_highest_addr(struct dcssblk_dev_info *dev_info) |
| 183 | { |
| 184 | unsigned long highest_addr; |
| 185 | struct segment_info *entry; |
| 186 | |
| 187 | highest_addr = 0; |
| 188 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 189 | if (highest_addr < entry->end) |
| 190 | highest_addr = entry->end; |
| 191 | } |
| 192 | return highest_addr; |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * get the lowest address of the multi-segment block. |
| 197 | */ |
| 198 | static unsigned long |
| 199 | dcssblk_find_lowest_addr(struct dcssblk_dev_info *dev_info) |
| 200 | { |
| 201 | int set_first; |
| 202 | unsigned long lowest_addr; |
| 203 | struct segment_info *entry; |
| 204 | |
| 205 | set_first = 0; |
| 206 | lowest_addr = 0; |
| 207 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 208 | if (set_first == 0) { |
| 209 | lowest_addr = entry->start; |
| 210 | set_first = 1; |
| 211 | } else { |
| 212 | if (lowest_addr > entry->start) |
| 213 | lowest_addr = entry->start; |
| 214 | } |
| 215 | } |
| 216 | return lowest_addr; |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * Check continuity of segments. |
| 221 | */ |
| 222 | static int |
| 223 | dcssblk_is_continuous(struct dcssblk_dev_info *dev_info) |
| 224 | { |
| 225 | int i, j, rc; |
| 226 | struct segment_info *sort_list, *entry, temp; |
| 227 | |
| 228 | if (dev_info->num_of_segments <= 1) |
| 229 | return 0; |
| 230 | |
| 231 | sort_list = kzalloc( |
| 232 | sizeof(struct segment_info) * dev_info->num_of_segments, |
| 233 | GFP_KERNEL); |
| 234 | if (sort_list == NULL) |
| 235 | return -ENOMEM; |
| 236 | i = 0; |
| 237 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 238 | memcpy(&sort_list[i], entry, sizeof(struct segment_info)); |
| 239 | i++; |
| 240 | } |
| 241 | |
| 242 | /* sort segments */ |
| 243 | for (i = 0; i < dev_info->num_of_segments; i++) |
| 244 | for (j = 0; j < dev_info->num_of_segments; j++) |
| 245 | if (sort_list[j].start > sort_list[i].start) { |
| 246 | memcpy(&temp, &sort_list[i], |
| 247 | sizeof(struct segment_info)); |
| 248 | memcpy(&sort_list[i], &sort_list[j], |
| 249 | sizeof(struct segment_info)); |
| 250 | memcpy(&sort_list[j], &temp, |
| 251 | sizeof(struct segment_info)); |
| 252 | } |
| 253 | |
| 254 | /* check continuity */ |
| 255 | for (i = 0; i < dev_info->num_of_segments - 1; i++) { |
| 256 | if ((sort_list[i].end + 1) != sort_list[i+1].start) { |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 257 | pr_err("Adjacent DCSSs %s and %s are not " |
| 258 | "contiguous\n", sort_list[i].segment_name, |
| 259 | sort_list[i+1].segment_name); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 260 | rc = -EINVAL; |
| 261 | goto out; |
| 262 | } |
| 263 | /* EN and EW are allowed in a block device */ |
| 264 | if (sort_list[i].segment_type != sort_list[i+1].segment_type) { |
| 265 | if (!(sort_list[i].segment_type & SEGMENT_EXCLUSIVE) || |
| 266 | (sort_list[i].segment_type == SEG_TYPE_ER) || |
| 267 | !(sort_list[i+1].segment_type & |
| 268 | SEGMENT_EXCLUSIVE) || |
| 269 | (sort_list[i+1].segment_type == SEG_TYPE_ER)) { |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 270 | pr_err("DCSS %s and DCSS %s have " |
| 271 | "incompatible types\n", |
| 272 | sort_list[i].segment_name, |
| 273 | sort_list[i+1].segment_name); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 274 | rc = -EINVAL; |
| 275 | goto out; |
| 276 | } |
| 277 | } |
| 278 | } |
| 279 | rc = 0; |
| 280 | out: |
| 281 | kfree(sort_list); |
| 282 | return rc; |
| 283 | } |
| 284 | |
| 285 | /* |
| 286 | * Load a segment |
| 287 | */ |
| 288 | static int |
| 289 | dcssblk_load_segment(char *name, struct segment_info **seg_info) |
| 290 | { |
| 291 | int rc; |
| 292 | |
| 293 | /* already loaded? */ |
| 294 | down_read(&dcssblk_devices_sem); |
| 295 | *seg_info = dcssblk_get_segment_by_name(name); |
| 296 | up_read(&dcssblk_devices_sem); |
| 297 | if (*seg_info != NULL) |
| 298 | return -EEXIST; |
| 299 | |
| 300 | /* get a struct segment_info */ |
| 301 | *seg_info = kzalloc(sizeof(struct segment_info), GFP_KERNEL); |
| 302 | if (*seg_info == NULL) |
| 303 | return -ENOMEM; |
| 304 | |
| 305 | strcpy((*seg_info)->segment_name, name); |
| 306 | |
| 307 | /* load the segment */ |
| 308 | rc = segment_load(name, SEGMENT_SHARED, |
| 309 | &(*seg_info)->start, &(*seg_info)->end); |
| 310 | if (rc < 0) { |
| 311 | segment_warning(rc, (*seg_info)->segment_name); |
| 312 | kfree(*seg_info); |
| 313 | } else { |
| 314 | INIT_LIST_HEAD(&(*seg_info)->lh); |
| 315 | (*seg_info)->segment_type = rc; |
| 316 | } |
| 317 | return rc; |
| 318 | } |
| 319 | |
Gerald Schaefer | 931bb68 | 2007-11-05 11:10:09 +0100 | [diff] [blame] | 320 | static void dcssblk_unregister_callback(struct device *dev) |
| 321 | { |
| 322 | device_unregister(dev); |
| 323 | put_device(dev); |
| 324 | } |
| 325 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 326 | /* |
| 327 | * device attribute for switching shared/nonshared (exclusive) |
| 328 | * operation (show + store) |
| 329 | */ |
| 330 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 331 | dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 332 | { |
| 333 | struct dcssblk_dev_info *dev_info; |
| 334 | |
| 335 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 336 | return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n"); |
| 337 | } |
| 338 | |
| 339 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 340 | dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | { |
| 342 | struct dcssblk_dev_info *dev_info; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 343 | struct segment_info *entry, *temp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | int rc; |
| 345 | |
Hongjie Yang | ded77fb | 2008-07-14 09:59:39 +0200 | [diff] [blame] | 346 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 347 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | down_write(&dcssblk_devices_sem); |
| 349 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 350 | if (atomic_read(&dev_info->use_count)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | rc = -EBUSY; |
| 352 | goto out; |
| 353 | } |
| 354 | if (inbuf[0] == '1') { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 355 | /* reload segments in shared mode */ |
| 356 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 357 | rc = segment_modify_shared(entry->segment_name, |
| 358 | SEGMENT_SHARED); |
| 359 | if (rc < 0) { |
| 360 | BUG_ON(rc == -EINVAL); |
| 361 | if (rc != -EAGAIN) |
| 362 | goto removeseg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 363 | } |
| 364 | } |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 365 | dev_info->is_shared = 1; |
| 366 | switch (dev_info->segment_type) { |
| 367 | case SEG_TYPE_SR: |
| 368 | case SEG_TYPE_ER: |
| 369 | case SEG_TYPE_SC: |
| 370 | set_disk_ro(dev_info->gd, 1); |
| 371 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | } else if (inbuf[0] == '0') { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 373 | /* reload segments in exclusive mode */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | if (dev_info->segment_type == SEG_TYPE_SC) { |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 375 | pr_err("DCSS %s is of type SC and cannot be " |
| 376 | "loaded as exclusive-writable\n", |
| 377 | dev_info->segment_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 378 | rc = -EINVAL; |
| 379 | goto out; |
| 380 | } |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 381 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 382 | rc = segment_modify_shared(entry->segment_name, |
| 383 | SEGMENT_EXCLUSIVE); |
| 384 | if (rc < 0) { |
| 385 | BUG_ON(rc == -EINVAL); |
| 386 | if (rc != -EAGAIN) |
| 387 | goto removeseg; |
| 388 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | } |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 390 | dev_info->is_shared = 0; |
| 391 | set_disk_ro(dev_info->gd, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 392 | } else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | rc = -EINVAL; |
| 394 | goto out; |
| 395 | } |
| 396 | rc = count; |
| 397 | goto out; |
| 398 | |
| 399 | removeseg: |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 400 | pr_err("DCSS device %s is removed after a failed access mode " |
| 401 | "change\n", dev_info->segment_name); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 402 | temp = entry; |
| 403 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 404 | if (entry != temp) |
| 405 | segment_unload(entry->segment_name); |
| 406 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | list_del(&dev_info->lh); |
| 408 | |
| 409 | del_gendisk(dev_info->gd); |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 410 | blk_cleanup_queue(dev_info->dcssblk_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | dev_info->gd->queue = NULL; |
| 412 | put_disk(dev_info->gd); |
Gerald Schaefer | 931bb68 | 2007-11-05 11:10:09 +0100 | [diff] [blame] | 413 | rc = device_schedule_callback(dev, dcssblk_unregister_callback); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 414 | out: |
| 415 | up_write(&dcssblk_devices_sem); |
| 416 | return rc; |
| 417 | } |
| 418 | |
| 419 | /* |
| 420 | * device attribute for save operation on current copy |
| 421 | * of the segment. If the segment is busy, saving will |
| 422 | * become pending until it gets released, which can be |
| 423 | * undone by storing a non-true value to this entry. |
| 424 | * (show + store) |
| 425 | */ |
| 426 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 427 | dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | { |
| 429 | struct dcssblk_dev_info *dev_info; |
| 430 | |
| 431 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 432 | return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n"); |
| 433 | } |
| 434 | |
| 435 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 436 | dcssblk_save_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | { |
| 438 | struct dcssblk_dev_info *dev_info; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 439 | struct segment_info *entry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 440 | |
Hongjie Yang | ded77fb | 2008-07-14 09:59:39 +0200 | [diff] [blame] | 441 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 444 | |
| 445 | down_write(&dcssblk_devices_sem); |
| 446 | if (inbuf[0] == '1') { |
| 447 | if (atomic_read(&dev_info->use_count) == 0) { |
| 448 | // device is idle => we save immediately |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 449 | pr_info("All DCSSs that map to device %s are " |
| 450 | "saved\n", dev_info->segment_name); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 451 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 452 | segment_save(entry->segment_name); |
| 453 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | } else { |
| 455 | // device is busy => we save it when it becomes |
| 456 | // idle in dcssblk_release |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 457 | pr_info("Device %s is in use, its DCSSs will be " |
| 458 | "saved when it becomes idle\n", |
| 459 | dev_info->segment_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 460 | dev_info->save_pending = 1; |
| 461 | } |
| 462 | } else if (inbuf[0] == '0') { |
| 463 | if (dev_info->save_pending) { |
| 464 | // device is busy & the user wants to undo his save |
| 465 | // request |
| 466 | dev_info->save_pending = 0; |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 467 | pr_info("A pending save request for device %s " |
| 468 | "has been canceled\n", |
| 469 | dev_info->segment_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | } |
| 471 | } else { |
| 472 | up_write(&dcssblk_devices_sem); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | return -EINVAL; |
| 474 | } |
| 475 | up_write(&dcssblk_devices_sem); |
| 476 | return count; |
| 477 | } |
| 478 | |
| 479 | /* |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 480 | * device attribute for showing all segments in a device |
| 481 | */ |
| 482 | static ssize_t |
| 483 | dcssblk_seglist_show(struct device *dev, struct device_attribute *attr, |
| 484 | char *buf) |
| 485 | { |
| 486 | int i; |
| 487 | |
| 488 | struct dcssblk_dev_info *dev_info; |
| 489 | struct segment_info *entry; |
| 490 | |
| 491 | down_read(&dcssblk_devices_sem); |
| 492 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
| 493 | i = 0; |
| 494 | buf[0] = '\0'; |
| 495 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 496 | strcpy(&buf[i], entry->segment_name); |
| 497 | i += strlen(entry->segment_name); |
| 498 | buf[i] = '\n'; |
| 499 | i++; |
| 500 | } |
| 501 | up_read(&dcssblk_devices_sem); |
| 502 | return i; |
| 503 | } |
| 504 | |
| 505 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | * device attribute for adding devices |
| 507 | */ |
| 508 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 509 | dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 510 | { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 511 | int rc, i, j, num_of_segments; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | struct dcssblk_dev_info *dev_info; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 513 | struct segment_info *seg_info, *temp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 514 | char *local_buf; |
| 515 | unsigned long seg_byte_size; |
| 516 | |
| 517 | dev_info = NULL; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 518 | seg_info = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | if (dev != dcssblk_root_dev) { |
| 520 | rc = -EINVAL; |
| 521 | goto out_nobuf; |
| 522 | } |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 523 | if ((count < 1) || (buf[0] == '\0') || (buf[0] == '\n')) { |
| 524 | rc = -ENAMETOOLONG; |
| 525 | goto out_nobuf; |
| 526 | } |
| 527 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 528 | local_buf = kmalloc(count + 1, GFP_KERNEL); |
| 529 | if (local_buf == NULL) { |
| 530 | rc = -ENOMEM; |
| 531 | goto out_nobuf; |
| 532 | } |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 533 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | /* |
| 535 | * parse input |
| 536 | */ |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 537 | num_of_segments = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 538 | for (i = 0; ((buf[i] != '\0') && (buf[i] != '\n') && i < count); i++) { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 539 | for (j = i; (buf[j] != ':') && |
| 540 | (buf[j] != '\0') && |
| 541 | (buf[j] != '\n') && |
| 542 | j < count; j++) { |
| 543 | local_buf[j-i] = toupper(buf[j]); |
| 544 | } |
| 545 | local_buf[j-i] = '\0'; |
| 546 | if (((j - i) == 0) || ((j - i) > 8)) { |
| 547 | rc = -ENAMETOOLONG; |
| 548 | goto seg_list_del; |
| 549 | } |
| 550 | |
| 551 | rc = dcssblk_load_segment(local_buf, &seg_info); |
| 552 | if (rc < 0) |
| 553 | goto seg_list_del; |
| 554 | /* |
| 555 | * get a struct dcssblk_dev_info |
| 556 | */ |
| 557 | if (num_of_segments == 0) { |
| 558 | dev_info = kzalloc(sizeof(struct dcssblk_dev_info), |
| 559 | GFP_KERNEL); |
| 560 | if (dev_info == NULL) { |
| 561 | rc = -ENOMEM; |
| 562 | goto out; |
| 563 | } |
| 564 | strcpy(dev_info->segment_name, local_buf); |
| 565 | dev_info->segment_type = seg_info->segment_type; |
| 566 | INIT_LIST_HEAD(&dev_info->seg_list); |
| 567 | } |
| 568 | list_add_tail(&seg_info->lh, &dev_info->seg_list); |
| 569 | num_of_segments++; |
| 570 | i = j; |
| 571 | |
| 572 | if ((buf[j] == '\0') || (buf[j] == '\n')) |
| 573 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 574 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 575 | |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 576 | /* no trailing colon at the end of the input */ |
| 577 | if ((i > 0) && (buf[i-1] == ':')) { |
| 578 | rc = -ENAMETOOLONG; |
| 579 | goto seg_list_del; |
| 580 | } |
| 581 | strlcpy(local_buf, buf, i + 1); |
| 582 | dev_info->num_of_segments = num_of_segments; |
| 583 | rc = dcssblk_is_continuous(dev_info); |
| 584 | if (rc < 0) |
| 585 | goto seg_list_del; |
| 586 | |
| 587 | dev_info->start = dcssblk_find_lowest_addr(dev_info); |
| 588 | dev_info->end = dcssblk_find_highest_addr(dev_info); |
| 589 | |
| 590 | dev_set_name(&dev_info->dev, dev_info->segment_name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | dev_info->dev.release = dcssblk_release_segment; |
| 592 | INIT_LIST_HEAD(&dev_info->lh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK); |
| 594 | if (dev_info->gd == NULL) { |
| 595 | rc = -ENOMEM; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 596 | goto seg_list_del; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 597 | } |
| 598 | dev_info->gd->major = dcssblk_major; |
| 599 | dev_info->gd->fops = &dcssblk_devops; |
| 600 | dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL); |
| 601 | dev_info->gd->queue = dev_info->dcssblk_queue; |
| 602 | dev_info->gd->private_data = dev_info; |
| 603 | dev_info->gd->driverfs_dev = &dev_info->dev; |
Heiko Carstens | c5411db | 2008-02-05 16:50:50 +0100 | [diff] [blame] | 604 | blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request); |
Martin K. Petersen | e1defc4 | 2009-05-22 17:17:49 -0400 | [diff] [blame] | 605 | blk_queue_logical_block_size(dev_info->dcssblk_queue, 4096); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 606 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | seg_byte_size = (dev_info->end - dev_info->start + 1); |
| 608 | set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 609 | pr_info("Loaded %s with total size %lu bytes and capacity %lu " |
| 610 | "sectors\n", local_buf, seg_byte_size, seg_byte_size >> 9); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 611 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | dev_info->save_pending = 0; |
| 613 | dev_info->is_shared = 1; |
| 614 | dev_info->dev.parent = dcssblk_root_dev; |
| 615 | |
| 616 | /* |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 617 | *get minor, add to list |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | */ |
| 619 | down_write(&dcssblk_devices_sem); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 620 | if (dcssblk_get_segment_by_name(local_buf)) { |
Gerald Schaefer | 04f64b5 | 2008-08-21 19:46:40 +0200 | [diff] [blame] | 621 | rc = -EEXIST; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 622 | goto release_gd; |
Gerald Schaefer | 04f64b5 | 2008-08-21 19:46:40 +0200 | [diff] [blame] | 623 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 624 | rc = dcssblk_assign_free_minor(dev_info); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 625 | if (rc) |
| 626 | goto release_gd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 627 | sprintf(dev_info->gd->disk_name, "dcssblk%d", |
Tejun Heo | f331c02 | 2008-09-03 09:01:48 +0200 | [diff] [blame] | 628 | MINOR(disk_devt(dev_info->gd))); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | list_add_tail(&dev_info->lh, &dcssblk_devices); |
| 630 | |
| 631 | if (!try_module_get(THIS_MODULE)) { |
| 632 | rc = -ENODEV; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 633 | goto dev_list_del; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | } |
| 635 | /* |
| 636 | * register the device |
| 637 | */ |
| 638 | rc = device_register(&dev_info->dev); |
| 639 | if (rc) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 640 | module_put(THIS_MODULE); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 641 | goto dev_list_del; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | } |
| 643 | get_device(&dev_info->dev); |
| 644 | rc = device_create_file(&dev_info->dev, &dev_attr_shared); |
| 645 | if (rc) |
| 646 | goto unregister_dev; |
| 647 | rc = device_create_file(&dev_info->dev, &dev_attr_save); |
| 648 | if (rc) |
| 649 | goto unregister_dev; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 650 | rc = device_create_file(&dev_info->dev, &dev_attr_seglist); |
| 651 | if (rc) |
| 652 | goto unregister_dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | |
Christian Borntraeger | 436d1bc | 2007-12-04 16:09:03 +0100 | [diff] [blame] | 654 | add_disk(dev_info->gd); |
| 655 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 656 | switch (dev_info->segment_type) { |
| 657 | case SEG_TYPE_SR: |
| 658 | case SEG_TYPE_ER: |
| 659 | case SEG_TYPE_SC: |
| 660 | set_disk_ro(dev_info->gd,1); |
| 661 | break; |
| 662 | default: |
| 663 | set_disk_ro(dev_info->gd,0); |
| 664 | break; |
| 665 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 666 | up_write(&dcssblk_devices_sem); |
| 667 | rc = count; |
| 668 | goto out; |
| 669 | |
| 670 | unregister_dev: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | list_del(&dev_info->lh); |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 672 | blk_cleanup_queue(dev_info->dcssblk_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | dev_info->gd->queue = NULL; |
| 674 | put_disk(dev_info->gd); |
| 675 | device_unregister(&dev_info->dev); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 676 | list_for_each_entry(seg_info, &dev_info->seg_list, lh) { |
| 677 | segment_unload(seg_info->segment_name); |
| 678 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | put_device(&dev_info->dev); |
| 680 | up_write(&dcssblk_devices_sem); |
| 681 | goto out; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 682 | dev_list_del: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | list_del(&dev_info->lh); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 684 | release_gd: |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 685 | blk_cleanup_queue(dev_info->dcssblk_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | dev_info->gd->queue = NULL; |
| 687 | put_disk(dev_info->gd); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 688 | up_write(&dcssblk_devices_sem); |
| 689 | seg_list_del: |
| 690 | if (dev_info == NULL) |
| 691 | goto out; |
| 692 | list_for_each_entry_safe(seg_info, temp, &dev_info->seg_list, lh) { |
| 693 | list_del(&seg_info->lh); |
| 694 | segment_unload(seg_info->segment_name); |
| 695 | kfree(seg_info); |
| 696 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | kfree(dev_info); |
| 698 | out: |
| 699 | kfree(local_buf); |
| 700 | out_nobuf: |
| 701 | return rc; |
| 702 | } |
| 703 | |
| 704 | /* |
| 705 | * device attribute for removing devices |
| 706 | */ |
| 707 | static ssize_t |
Yani Ioannou | e404e27 | 2005-05-17 06:42:58 -0400 | [diff] [blame] | 708 | dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 709 | { |
| 710 | struct dcssblk_dev_info *dev_info; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 711 | struct segment_info *entry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | int rc, i; |
| 713 | char *local_buf; |
| 714 | |
| 715 | if (dev != dcssblk_root_dev) { |
| 716 | return -EINVAL; |
| 717 | } |
| 718 | local_buf = kmalloc(count + 1, GFP_KERNEL); |
| 719 | if (local_buf == NULL) { |
| 720 | return -ENOMEM; |
| 721 | } |
| 722 | /* |
| 723 | * parse input |
| 724 | */ |
| 725 | for (i = 0; ((*(buf+i)!='\0') && (*(buf+i)!='\n') && i < count); i++) { |
| 726 | local_buf[i] = toupper(buf[i]); |
| 727 | } |
| 728 | local_buf[i] = '\0'; |
| 729 | if ((i == 0) || (i > 8)) { |
| 730 | rc = -ENAMETOOLONG; |
| 731 | goto out_buf; |
| 732 | } |
| 733 | |
| 734 | down_write(&dcssblk_devices_sem); |
| 735 | dev_info = dcssblk_get_device_by_name(local_buf); |
| 736 | if (dev_info == NULL) { |
| 737 | up_write(&dcssblk_devices_sem); |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 738 | pr_warning("Device %s cannot be removed because it is not a " |
| 739 | "known device\n", local_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 740 | rc = -ENODEV; |
| 741 | goto out_buf; |
| 742 | } |
| 743 | if (atomic_read(&dev_info->use_count) != 0) { |
| 744 | up_write(&dcssblk_devices_sem); |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 745 | pr_warning("Device %s cannot be removed while it is in " |
| 746 | "use\n", local_buf); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 747 | rc = -EBUSY; |
| 748 | goto out_buf; |
| 749 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 751 | list_del(&dev_info->lh); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | del_gendisk(dev_info->gd); |
Al Viro | 1312f40 | 2006-03-12 11:02:03 -0500 | [diff] [blame] | 753 | blk_cleanup_queue(dev_info->dcssblk_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | dev_info->gd->queue = NULL; |
| 755 | put_disk(dev_info->gd); |
| 756 | device_unregister(&dev_info->dev); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 757 | |
| 758 | /* unload all related segments */ |
| 759 | list_for_each_entry(entry, &dev_info->seg_list, lh) |
| 760 | segment_unload(entry->segment_name); |
| 761 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 762 | put_device(&dev_info->dev); |
| 763 | up_write(&dcssblk_devices_sem); |
| 764 | |
| 765 | rc = count; |
| 766 | out_buf: |
| 767 | kfree(local_buf); |
| 768 | return rc; |
| 769 | } |
| 770 | |
| 771 | static int |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 772 | dcssblk_open(struct block_device *bdev, fmode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 773 | { |
| 774 | struct dcssblk_dev_info *dev_info; |
| 775 | int rc; |
| 776 | |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 777 | dev_info = bdev->bd_disk->private_data; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | if (NULL == dev_info) { |
| 779 | rc = -ENODEV; |
| 780 | goto out; |
| 781 | } |
| 782 | atomic_inc(&dev_info->use_count); |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 783 | bdev->bd_block_size = 4096; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | rc = 0; |
| 785 | out: |
| 786 | return rc; |
| 787 | } |
| 788 | |
| 789 | static int |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 790 | dcssblk_release(struct gendisk *disk, fmode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | { |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 792 | struct dcssblk_dev_info *dev_info = disk->private_data; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 793 | struct segment_info *entry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 794 | int rc; |
| 795 | |
Al Viro | 46d7432 | 2008-03-02 10:37:41 -0500 | [diff] [blame] | 796 | if (!dev_info) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 797 | rc = -ENODEV; |
| 798 | goto out; |
| 799 | } |
| 800 | down_write(&dcssblk_devices_sem); |
| 801 | if (atomic_dec_and_test(&dev_info->use_count) |
| 802 | && (dev_info->save_pending)) { |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 803 | pr_info("Device %s has become idle and is being saved " |
| 804 | "now\n", dev_info->segment_name); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 805 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
| 806 | segment_save(entry->segment_name); |
| 807 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 808 | dev_info->save_pending = 0; |
| 809 | } |
| 810 | up_write(&dcssblk_devices_sem); |
| 811 | rc = 0; |
| 812 | out: |
| 813 | return rc; |
| 814 | } |
| 815 | |
| 816 | static int |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 817 | dcssblk_make_request(struct request_queue *q, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | { |
| 819 | struct dcssblk_dev_info *dev_info; |
| 820 | struct bio_vec *bvec; |
| 821 | unsigned long index; |
| 822 | unsigned long page_addr; |
| 823 | unsigned long source_addr; |
| 824 | unsigned long bytes_done; |
| 825 | int i; |
| 826 | |
| 827 | bytes_done = 0; |
| 828 | dev_info = bio->bi_bdev->bd_disk->private_data; |
| 829 | if (dev_info == NULL) |
| 830 | goto fail; |
| 831 | if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0) |
| 832 | /* Request is not page-aligned. */ |
| 833 | goto fail; |
| 834 | if (((bio->bi_size >> 9) + bio->bi_sector) |
| 835 | > get_capacity(bio->bi_bdev->bd_disk)) { |
| 836 | /* Request beyond end of DCSS segment. */ |
| 837 | goto fail; |
| 838 | } |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 839 | /* verify data transfer direction */ |
| 840 | if (dev_info->is_shared) { |
| 841 | switch (dev_info->segment_type) { |
| 842 | case SEG_TYPE_SR: |
| 843 | case SEG_TYPE_ER: |
| 844 | case SEG_TYPE_SC: |
| 845 | /* cannot write to these segments */ |
| 846 | if (bio_data_dir(bio) == WRITE) { |
Hongjie Yang | 93098bf | 2008-12-25 13:39:45 +0100 | [diff] [blame] | 847 | pr_warning("Writing to %s failed because it " |
| 848 | "is a read-only device\n", |
Kay Sievers | 2a0217d | 2008-10-10 21:33:09 +0200 | [diff] [blame] | 849 | dev_name(&dev_info->dev)); |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 850 | goto fail; |
| 851 | } |
| 852 | } |
| 853 | } |
| 854 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | index = (bio->bi_sector >> 3); |
| 856 | bio_for_each_segment(bvec, bio, i) { |
| 857 | page_addr = (unsigned long) |
| 858 | page_address(bvec->bv_page) + bvec->bv_offset; |
| 859 | source_addr = dev_info->start + (index<<12) + bytes_done; |
Roel Kluin | 39f73b2 | 2008-02-19 15:29:33 +0100 | [diff] [blame] | 860 | if (unlikely((page_addr & 4095) != 0) || (bvec->bv_len & 4095) != 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | // More paranoia. |
| 862 | goto fail; |
| 863 | if (bio_data_dir(bio) == READ) { |
| 864 | memcpy((void*)page_addr, (void*)source_addr, |
| 865 | bvec->bv_len); |
| 866 | } else { |
| 867 | memcpy((void*)source_addr, (void*)page_addr, |
| 868 | bvec->bv_len); |
| 869 | } |
| 870 | bytes_done += bvec->bv_len; |
| 871 | } |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 872 | bio_endio(bio, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 873 | return 0; |
| 874 | fail: |
NeilBrown | 6712ecf | 2007-09-27 12:47:43 +0200 | [diff] [blame] | 875 | bio_io_error(bio); |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 876 | return 0; |
| 877 | } |
| 878 | |
| 879 | static int |
| 880 | dcssblk_direct_access (struct block_device *bdev, sector_t secnum, |
Jared Hulbert | 30afcb4 | 2008-04-28 02:13:02 -0700 | [diff] [blame] | 881 | void **kaddr, unsigned long *pfn) |
Carsten Otte | 420edbc | 2005-06-23 22:05:23 -0700 | [diff] [blame] | 882 | { |
| 883 | struct dcssblk_dev_info *dev_info; |
| 884 | unsigned long pgoff; |
| 885 | |
| 886 | dev_info = bdev->bd_disk->private_data; |
| 887 | if (!dev_info) |
| 888 | return -ENODEV; |
| 889 | if (secnum % (PAGE_SIZE/512)) |
| 890 | return -EINVAL; |
| 891 | pgoff = secnum / (PAGE_SIZE / 512); |
| 892 | if ((pgoff+1)*PAGE_SIZE-1 > dev_info->end - dev_info->start) |
| 893 | return -ERANGE; |
Jared Hulbert | 30afcb4 | 2008-04-28 02:13:02 -0700 | [diff] [blame] | 894 | *kaddr = (void *) (dev_info->start+pgoff*PAGE_SIZE); |
| 895 | *pfn = virt_to_phys(*kaddr) >> PAGE_SHIFT; |
| 896 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | return 0; |
| 898 | } |
| 899 | |
| 900 | static void |
| 901 | dcssblk_check_params(void) |
| 902 | { |
| 903 | int rc, i, j, k; |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 904 | char buf[DCSSBLK_PARM_LEN + 1]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 905 | struct dcssblk_dev_info *dev_info; |
| 906 | |
| 907 | for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0'); |
| 908 | i++) { |
| 909 | for (j = i; (dcssblk_segments[j] != ',') && |
| 910 | (dcssblk_segments[j] != '\0') && |
| 911 | (dcssblk_segments[j] != '(') && |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 912 | (j < DCSSBLK_PARM_LEN); j++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 913 | { |
| 914 | buf[j-i] = dcssblk_segments[j]; |
| 915 | } |
| 916 | buf[j-i] = '\0'; |
Cornelia Huck | f901e5d1 | 2005-06-25 14:55:29 -0700 | [diff] [blame] | 917 | rc = dcssblk_add_store(dcssblk_root_dev, NULL, buf, j-i); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | if ((rc >= 0) && (dcssblk_segments[j] == '(')) { |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 919 | for (k = 0; (buf[k] != ':') && (buf[k] != '\0'); k++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 920 | buf[k] = toupper(buf[k]); |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 921 | buf[k] = '\0'; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 922 | if (!strncmp(&dcssblk_segments[j], "(local)", 7)) { |
| 923 | down_read(&dcssblk_devices_sem); |
| 924 | dev_info = dcssblk_get_device_by_name(buf); |
| 925 | up_read(&dcssblk_devices_sem); |
| 926 | if (dev_info) |
| 927 | dcssblk_shared_store(&dev_info->dev, |
Cornelia Huck | f901e5d1 | 2005-06-25 14:55:29 -0700 | [diff] [blame] | 928 | NULL, "0\n", 2); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 929 | } |
| 930 | } |
| 931 | while ((dcssblk_segments[j] != ',') && |
| 932 | (dcssblk_segments[j] != '\0')) |
| 933 | { |
| 934 | j++; |
| 935 | } |
| 936 | if (dcssblk_segments[j] == '\0') |
| 937 | break; |
| 938 | i = j; |
| 939 | } |
| 940 | } |
| 941 | |
| 942 | /* |
| 943 | * The init/exit functions. |
| 944 | */ |
| 945 | static void __exit |
| 946 | dcssblk_exit(void) |
| 947 | { |
Mark McLoughlin | 035da16 | 2008-12-15 12:58:29 +0000 | [diff] [blame] | 948 | root_device_unregister(dcssblk_root_dev); |
Akinobu Mita | 00d5940 | 2007-07-17 04:03:46 -0700 | [diff] [blame] | 949 | unregister_blkdev(dcssblk_major, DCSSBLK_NAME); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 950 | } |
| 951 | |
| 952 | static int __init |
| 953 | dcssblk_init(void) |
| 954 | { |
| 955 | int rc; |
| 956 | |
Mark McLoughlin | 035da16 | 2008-12-15 12:58:29 +0000 | [diff] [blame] | 957 | dcssblk_root_dev = root_device_register("dcssblk"); |
Hongjie Yang | ded77fb | 2008-07-14 09:59:39 +0200 | [diff] [blame] | 958 | if (IS_ERR(dcssblk_root_dev)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 959 | return PTR_ERR(dcssblk_root_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 960 | rc = device_create_file(dcssblk_root_dev, &dev_attr_add); |
| 961 | if (rc) { |
Mark McLoughlin | 035da16 | 2008-12-15 12:58:29 +0000 | [diff] [blame] | 962 | root_device_unregister(dcssblk_root_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 963 | return rc; |
| 964 | } |
| 965 | rc = device_create_file(dcssblk_root_dev, &dev_attr_remove); |
| 966 | if (rc) { |
Mark McLoughlin | 035da16 | 2008-12-15 12:58:29 +0000 | [diff] [blame] | 967 | root_device_unregister(dcssblk_root_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 968 | return rc; |
| 969 | } |
| 970 | rc = register_blkdev(0, DCSSBLK_NAME); |
| 971 | if (rc < 0) { |
Mark McLoughlin | 035da16 | 2008-12-15 12:58:29 +0000 | [diff] [blame] | 972 | root_device_unregister(dcssblk_root_dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | return rc; |
| 974 | } |
| 975 | dcssblk_major = rc; |
| 976 | init_rwsem(&dcssblk_devices_sem); |
| 977 | |
| 978 | dcssblk_check_params(); |
| 979 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 980 | return 0; |
| 981 | } |
| 982 | |
| 983 | module_init(dcssblk_init); |
| 984 | module_exit(dcssblk_exit); |
| 985 | |
| 986 | module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444); |
| 987 | MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, " |
Hongjie Yang | b2300b9 | 2008-10-10 21:33:21 +0200 | [diff] [blame] | 988 | "comma-separated list, names in each set separated " |
| 989 | "by commas are separated by colons, each set contains " |
| 990 | "names of contiguous segments and each name max. 8 chars.\n" |
| 991 | "Adding \"(local)\" to the end of each set equals echoing 0 " |
| 992 | "to /sys/devices/dcssblk/<device name>/shared after loading " |
| 993 | "the contiguous segments - \n" |
| 994 | "e.g. segments=\"mydcss1,mydcss2:mydcss3,mydcss4(local)\""); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 995 | |
| 996 | MODULE_LICENSE("GPL"); |