block, bfq: don't dereference bic before null checking it
[linux-2.6/btrfs-unstable.git] / drivers / ide / ide-gd.c
blobe823394ed543470e98114a8a33e3ceb9ab084b24
1 #include <linux/module.h>
2 #include <linux/types.h>
3 #include <linux/string.h>
4 #include <linux/kernel.h>
5 #include <linux/errno.h>
6 #include <linux/genhd.h>
7 #include <linux/mutex.h>
8 #include <linux/ide.h>
9 #include <linux/hdreg.h>
10 #include <linux/dmi.h>
11 #include <linux/slab.h>
13 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
14 #define IDE_DISK_MINORS (1 << PARTN_BITS)
15 #else
16 #define IDE_DISK_MINORS 0
17 #endif
19 #include "ide-disk.h"
20 #include "ide-floppy.h"
22 #define IDE_GD_VERSION "1.18"
24 /* module parameters */
25 static DEFINE_MUTEX(ide_gd_mutex);
26 static unsigned long debug_mask;
27 module_param(debug_mask, ulong, 0644);
29 static DEFINE_MUTEX(ide_disk_ref_mutex);
31 static void ide_disk_release(struct device *);
33 static struct ide_disk_obj *ide_disk_get(struct gendisk *disk)
35 struct ide_disk_obj *idkp = NULL;
37 mutex_lock(&ide_disk_ref_mutex);
38 idkp = ide_drv_g(disk, ide_disk_obj);
39 if (idkp) {
40 if (ide_device_get(idkp->drive))
41 idkp = NULL;
42 else
43 get_device(&idkp->dev);
45 mutex_unlock(&ide_disk_ref_mutex);
46 return idkp;
49 static void ide_disk_put(struct ide_disk_obj *idkp)
51 ide_drive_t *drive = idkp->drive;
53 mutex_lock(&ide_disk_ref_mutex);
54 put_device(&idkp->dev);
55 ide_device_put(drive);
56 mutex_unlock(&ide_disk_ref_mutex);
59 sector_t ide_gd_capacity(ide_drive_t *drive)
61 return drive->capacity64;
64 static int ide_gd_probe(ide_drive_t *);
66 static void ide_gd_remove(ide_drive_t *drive)
68 struct ide_disk_obj *idkp = drive->driver_data;
69 struct gendisk *g = idkp->disk;
71 ide_proc_unregister_driver(drive, idkp->driver);
72 device_del(&idkp->dev);
73 del_gendisk(g);
74 drive->disk_ops->flush(drive);
76 mutex_lock(&ide_disk_ref_mutex);
77 put_device(&idkp->dev);
78 mutex_unlock(&ide_disk_ref_mutex);
81 static void ide_disk_release(struct device *dev)
83 struct ide_disk_obj *idkp = to_ide_drv(dev, ide_disk_obj);
84 ide_drive_t *drive = idkp->drive;
85 struct gendisk *g = idkp->disk;
87 drive->disk_ops = NULL;
88 drive->driver_data = NULL;
89 g->private_data = NULL;
90 put_disk(g);
91 kfree(idkp);
95 * On HPA drives the capacity needs to be
96 * reinitialized on resume otherwise the disk
97 * can not be used and a hard reset is required
99 static void ide_gd_resume(ide_drive_t *drive)
101 if (ata_id_hpa_enabled(drive->id))
102 (void)drive->disk_ops->get_capacity(drive);
105 static const struct dmi_system_id ide_coldreboot_table[] = {
107 /* Acer TravelMate 66x cuts power during reboot */
108 .ident = "Acer TravelMate 660",
109 .matches = {
110 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
111 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 660"),
115 { } /* terminate list */
118 static void ide_gd_shutdown(ide_drive_t *drive)
120 #ifdef CONFIG_ALPHA
121 /* On Alpha, halt(8) doesn't actually turn the machine off,
122 it puts you into the sort of firmware monitor. Typically,
123 it's used to boot another kernel image, so it's not much
124 different from reboot(8). Therefore, we don't need to
125 spin down the disk in this case, especially since Alpha
126 firmware doesn't handle disks in standby mode properly.
127 On the other hand, it's reasonably safe to turn the power
128 off when the shutdown process reaches the firmware prompt,
129 as the firmware initialization takes rather long time -
130 at least 10 seconds, which should be sufficient for
131 the disk to expire its write cache. */
132 if (system_state != SYSTEM_POWER_OFF) {
133 #else
134 if (system_state == SYSTEM_RESTART &&
135 !dmi_check_system(ide_coldreboot_table)) {
136 #endif
137 drive->disk_ops->flush(drive);
138 return;
141 printk(KERN_INFO "Shutdown: %s\n", drive->name);
143 drive->gendev.bus->suspend(&drive->gendev, PMSG_SUSPEND);
146 #ifdef CONFIG_IDE_PROC_FS
147 static ide_proc_entry_t *ide_disk_proc_entries(ide_drive_t *drive)
149 return (drive->media == ide_disk) ? ide_disk_proc : ide_floppy_proc;
152 static const struct ide_proc_devset *ide_disk_proc_devsets(ide_drive_t *drive)
154 return (drive->media == ide_disk) ? ide_disk_settings
155 : ide_floppy_settings;
157 #endif
159 static ide_startstop_t ide_gd_do_request(ide_drive_t *drive,
160 struct request *rq, sector_t sector)
162 return drive->disk_ops->do_request(drive, rq, sector);
165 static struct ide_driver ide_gd_driver = {
166 .gen_driver = {
167 .owner = THIS_MODULE,
168 .name = "ide-gd",
169 .bus = &ide_bus_type,
171 .probe = ide_gd_probe,
172 .remove = ide_gd_remove,
173 .resume = ide_gd_resume,
174 .shutdown = ide_gd_shutdown,
175 .version = IDE_GD_VERSION,
176 .do_request = ide_gd_do_request,
177 #ifdef CONFIG_IDE_PROC_FS
178 .proc_entries = ide_disk_proc_entries,
179 .proc_devsets = ide_disk_proc_devsets,
180 #endif
183 static int ide_gd_open(struct block_device *bdev, fmode_t mode)
185 struct gendisk *disk = bdev->bd_disk;
186 struct ide_disk_obj *idkp;
187 ide_drive_t *drive;
188 int ret = 0;
190 idkp = ide_disk_get(disk);
191 if (idkp == NULL)
192 return -ENXIO;
194 drive = idkp->drive;
196 ide_debug_log(IDE_DBG_FUNC, "enter");
198 idkp->openers++;
200 if ((drive->dev_flags & IDE_DFLAG_REMOVABLE) && idkp->openers == 1) {
201 drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
202 /* Just in case */
204 ret = drive->disk_ops->init_media(drive, disk);
207 * Allow O_NDELAY to open a drive without a disk, or with an
208 * unreadable disk, so that we can get the format capacity
209 * of the drive or begin the format - Sam
211 if (ret && (mode & FMODE_NDELAY) == 0) {
212 ret = -EIO;
213 goto out_put_idkp;
216 if ((drive->dev_flags & IDE_DFLAG_WP) && (mode & FMODE_WRITE)) {
217 ret = -EROFS;
218 goto out_put_idkp;
222 * Ignore the return code from door_lock,
223 * since the open() has already succeeded,
224 * and the door_lock is irrelevant at this point.
226 drive->disk_ops->set_doorlock(drive, disk, 1);
227 drive->dev_flags |= IDE_DFLAG_MEDIA_CHANGED;
228 check_disk_change(bdev);
229 } else if (drive->dev_flags & IDE_DFLAG_FORMAT_IN_PROGRESS) {
230 ret = -EBUSY;
231 goto out_put_idkp;
233 return 0;
235 out_put_idkp:
236 idkp->openers--;
237 ide_disk_put(idkp);
238 return ret;
241 static int ide_gd_unlocked_open(struct block_device *bdev, fmode_t mode)
243 int ret;
245 mutex_lock(&ide_gd_mutex);
246 ret = ide_gd_open(bdev, mode);
247 mutex_unlock(&ide_gd_mutex);
249 return ret;
253 static void ide_gd_release(struct gendisk *disk, fmode_t mode)
255 struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
256 ide_drive_t *drive = idkp->drive;
258 ide_debug_log(IDE_DBG_FUNC, "enter");
260 mutex_lock(&ide_gd_mutex);
261 if (idkp->openers == 1)
262 drive->disk_ops->flush(drive);
264 if ((drive->dev_flags & IDE_DFLAG_REMOVABLE) && idkp->openers == 1) {
265 drive->disk_ops->set_doorlock(drive, disk, 0);
266 drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
269 idkp->openers--;
271 ide_disk_put(idkp);
272 mutex_unlock(&ide_gd_mutex);
275 static int ide_gd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
277 struct ide_disk_obj *idkp = ide_drv_g(bdev->bd_disk, ide_disk_obj);
278 ide_drive_t *drive = idkp->drive;
280 geo->heads = drive->bios_head;
281 geo->sectors = drive->bios_sect;
282 geo->cylinders = (u16)drive->bios_cyl; /* truncate */
283 return 0;
286 static unsigned int ide_gd_check_events(struct gendisk *disk,
287 unsigned int clearing)
289 struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
290 ide_drive_t *drive = idkp->drive;
291 bool ret;
293 /* do not scan partitions twice if this is a removable device */
294 if (drive->dev_flags & IDE_DFLAG_ATTACH) {
295 drive->dev_flags &= ~IDE_DFLAG_ATTACH;
296 return 0;
300 * The following is used to force revalidation on the first open on
301 * removeable devices, and never gets reported to userland as
302 * genhd->events is 0. This is intended as removeable ide disk
303 * can't really detect MEDIA_CHANGE events.
305 ret = drive->dev_flags & IDE_DFLAG_MEDIA_CHANGED;
306 drive->dev_flags &= ~IDE_DFLAG_MEDIA_CHANGED;
308 return ret ? DISK_EVENT_MEDIA_CHANGE : 0;
311 static void ide_gd_unlock_native_capacity(struct gendisk *disk)
313 struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
314 ide_drive_t *drive = idkp->drive;
315 const struct ide_disk_ops *disk_ops = drive->disk_ops;
317 if (disk_ops->unlock_native_capacity)
318 disk_ops->unlock_native_capacity(drive);
321 static int ide_gd_revalidate_disk(struct gendisk *disk)
323 struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
324 ide_drive_t *drive = idkp->drive;
326 if (ide_gd_check_events(disk, 0))
327 drive->disk_ops->get_capacity(drive);
329 set_capacity(disk, ide_gd_capacity(drive));
330 return 0;
333 static int ide_gd_ioctl(struct block_device *bdev, fmode_t mode,
334 unsigned int cmd, unsigned long arg)
336 struct ide_disk_obj *idkp = ide_drv_g(bdev->bd_disk, ide_disk_obj);
337 ide_drive_t *drive = idkp->drive;
339 return drive->disk_ops->ioctl(drive, bdev, mode, cmd, arg);
342 static const struct block_device_operations ide_gd_ops = {
343 .owner = THIS_MODULE,
344 .open = ide_gd_unlocked_open,
345 .release = ide_gd_release,
346 .ioctl = ide_gd_ioctl,
347 .getgeo = ide_gd_getgeo,
348 .check_events = ide_gd_check_events,
349 .unlock_native_capacity = ide_gd_unlock_native_capacity,
350 .revalidate_disk = ide_gd_revalidate_disk
353 static int ide_gd_probe(ide_drive_t *drive)
355 const struct ide_disk_ops *disk_ops = NULL;
356 struct ide_disk_obj *idkp;
357 struct gendisk *g;
359 /* strstr("foo", "") is non-NULL */
360 if (!strstr("ide-gd", drive->driver_req))
361 goto failed;
363 #ifdef CONFIG_IDE_GD_ATA
364 if (drive->media == ide_disk)
365 disk_ops = &ide_ata_disk_ops;
366 #endif
367 #ifdef CONFIG_IDE_GD_ATAPI
368 if (drive->media == ide_floppy)
369 disk_ops = &ide_atapi_disk_ops;
370 #endif
371 if (disk_ops == NULL)
372 goto failed;
374 if (disk_ops->check(drive, DRV_NAME) == 0) {
375 printk(KERN_ERR PFX "%s: not supported by this driver\n",
376 drive->name);
377 goto failed;
380 idkp = kzalloc(sizeof(*idkp), GFP_KERNEL);
381 if (!idkp) {
382 printk(KERN_ERR PFX "%s: can't allocate a disk structure\n",
383 drive->name);
384 goto failed;
387 g = alloc_disk_node(IDE_DISK_MINORS, hwif_to_node(drive->hwif));
388 if (!g)
389 goto out_free_idkp;
391 ide_init_disk(g, drive);
393 idkp->dev.parent = &drive->gendev;
394 idkp->dev.release = ide_disk_release;
395 dev_set_name(&idkp->dev, "%s", dev_name(&drive->gendev));
397 if (device_register(&idkp->dev))
398 goto out_free_disk;
400 idkp->drive = drive;
401 idkp->driver = &ide_gd_driver;
402 idkp->disk = g;
404 g->private_data = &idkp->driver;
406 drive->driver_data = idkp;
407 drive->debug_mask = debug_mask;
408 drive->disk_ops = disk_ops;
410 disk_ops->setup(drive);
412 set_capacity(g, ide_gd_capacity(drive));
414 g->minors = IDE_DISK_MINORS;
415 g->flags |= GENHD_FL_EXT_DEVT;
416 if (drive->dev_flags & IDE_DFLAG_REMOVABLE)
417 g->flags = GENHD_FL_REMOVABLE;
418 g->fops = &ide_gd_ops;
419 device_add_disk(&drive->gendev, g);
420 return 0;
422 out_free_disk:
423 put_disk(g);
424 out_free_idkp:
425 kfree(idkp);
426 failed:
427 return -ENODEV;
430 static int __init ide_gd_init(void)
432 printk(KERN_INFO DRV_NAME " driver " IDE_GD_VERSION "\n");
433 return driver_register(&ide_gd_driver.gen_driver);
436 static void __exit ide_gd_exit(void)
438 driver_unregister(&ide_gd_driver.gen_driver);
441 MODULE_ALIAS("ide:*m-disk*");
442 MODULE_ALIAS("ide-disk");
443 MODULE_ALIAS("ide:*m-floppy*");
444 MODULE_ALIAS("ide-floppy");
445 module_init(ide_gd_init);
446 module_exit(ide_gd_exit);
447 MODULE_LICENSE("GPL");
448 MODULE_DESCRIPTION("generic ATA/ATAPI disk driver");