ide: use lock bitops for ports serialization (v2)
[linux-2.6] / drivers / ide / ide-gd.c
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
11 #if !defined(CONFIG_DEBUG_BLOCK_EXT_DEVT)
12 #define IDE_DISK_MINORS         (1 << PARTN_BITS)
13 #else
14 #define IDE_DISK_MINORS         0
15 #endif
16
17 #include "ide-disk.h"
18 #include "ide-floppy.h"
19
20 #define IDE_GD_VERSION  "1.18"
21
22 /* module parameters */
23 static unsigned long debug_mask;
24 module_param(debug_mask, ulong, 0644);
25
26 static DEFINE_MUTEX(ide_disk_ref_mutex);
27
28 static void ide_disk_release(struct kref *);
29
30 static struct ide_disk_obj *ide_disk_get(struct gendisk *disk)
31 {
32         struct ide_disk_obj *idkp = NULL;
33
34         mutex_lock(&ide_disk_ref_mutex);
35         idkp = ide_drv_g(disk, ide_disk_obj);
36         if (idkp) {
37                 if (ide_device_get(idkp->drive))
38                         idkp = NULL;
39                 else
40                         kref_get(&idkp->kref);
41         }
42         mutex_unlock(&ide_disk_ref_mutex);
43         return idkp;
44 }
45
46 static void ide_disk_put(struct ide_disk_obj *idkp)
47 {
48         ide_drive_t *drive = idkp->drive;
49
50         mutex_lock(&ide_disk_ref_mutex);
51         kref_put(&idkp->kref, ide_disk_release);
52         ide_device_put(drive);
53         mutex_unlock(&ide_disk_ref_mutex);
54 }
55
56 sector_t ide_gd_capacity(ide_drive_t *drive)
57 {
58         return drive->capacity64;
59 }
60
61 static int ide_gd_probe(ide_drive_t *);
62
63 static void ide_gd_remove(ide_drive_t *drive)
64 {
65         struct ide_disk_obj *idkp = drive->driver_data;
66         struct gendisk *g = idkp->disk;
67
68         ide_proc_unregister_driver(drive, idkp->driver);
69
70         del_gendisk(g);
71
72         drive->disk_ops->flush(drive);
73
74         ide_disk_put(idkp);
75 }
76
77 static void ide_disk_release(struct kref *kref)
78 {
79         struct ide_disk_obj *idkp = to_ide_drv(kref, ide_disk_obj);
80         ide_drive_t *drive = idkp->drive;
81         struct gendisk *g = idkp->disk;
82
83         drive->disk_ops = NULL;
84         drive->driver_data = NULL;
85         g->private_data = NULL;
86         put_disk(g);
87         kfree(idkp);
88 }
89
90 /*
91  * On HPA drives the capacity needs to be
92  * reinitilized on resume otherwise the disk
93  * can not be used and a hard reset is required
94  */
95 static void ide_gd_resume(ide_drive_t *drive)
96 {
97         if (ata_id_hpa_enabled(drive->id))
98                 (void)drive->disk_ops->get_capacity(drive);
99 }
100
101 static void ide_gd_shutdown(ide_drive_t *drive)
102 {
103 #ifdef  CONFIG_ALPHA
104         /* On Alpha, halt(8) doesn't actually turn the machine off,
105            it puts you into the sort of firmware monitor. Typically,
106            it's used to boot another kernel image, so it's not much
107            different from reboot(8). Therefore, we don't need to
108            spin down the disk in this case, especially since Alpha
109            firmware doesn't handle disks in standby mode properly.
110            On the other hand, it's reasonably safe to turn the power
111            off when the shutdown process reaches the firmware prompt,
112            as the firmware initialization takes rather long time -
113            at least 10 seconds, which should be sufficient for
114            the disk to expire its write cache. */
115         if (system_state != SYSTEM_POWER_OFF) {
116 #else
117         if (system_state == SYSTEM_RESTART) {
118 #endif
119                 drive->disk_ops->flush(drive);
120                 return;
121         }
122
123         printk(KERN_INFO "Shutdown: %s\n", drive->name);
124
125         drive->gendev.bus->suspend(&drive->gendev, PMSG_SUSPEND);
126 }
127
128 #ifdef CONFIG_IDE_PROC_FS
129 static ide_proc_entry_t *ide_disk_proc_entries(ide_drive_t *drive)
130 {
131         return (drive->media == ide_disk) ? ide_disk_proc : ide_floppy_proc;
132 }
133
134 static const struct ide_proc_devset *ide_disk_proc_devsets(ide_drive_t *drive)
135 {
136         return (drive->media == ide_disk) ? ide_disk_settings
137                                           : ide_floppy_settings;
138 }
139 #endif
140
141 static ide_startstop_t ide_gd_do_request(ide_drive_t *drive,
142                                          struct request *rq, sector_t sector)
143 {
144         return drive->disk_ops->do_request(drive, rq, sector);
145 }
146
147 static int ide_gd_end_request(ide_drive_t *drive, int uptodate, int nrsecs)
148 {
149         return drive->disk_ops->end_request(drive, uptodate, nrsecs);
150 }
151
152 static ide_driver_t ide_gd_driver = {
153         .gen_driver = {
154                 .owner          = THIS_MODULE,
155                 .name           = "ide-gd",
156                 .bus            = &ide_bus_type,
157         },
158         .probe                  = ide_gd_probe,
159         .remove                 = ide_gd_remove,
160         .resume                 = ide_gd_resume,
161         .shutdown               = ide_gd_shutdown,
162         .version                = IDE_GD_VERSION,
163         .do_request             = ide_gd_do_request,
164         .end_request            = ide_gd_end_request,
165         .error                  = __ide_error,
166 #ifdef CONFIG_IDE_PROC_FS
167         .proc_entries           = ide_disk_proc_entries,
168         .proc_devsets           = ide_disk_proc_devsets,
169 #endif
170 };
171
172 static int ide_gd_open(struct block_device *bdev, fmode_t mode)
173 {
174         struct gendisk *disk = bdev->bd_disk;
175         struct ide_disk_obj *idkp;
176         ide_drive_t *drive;
177         int ret = 0;
178
179         idkp = ide_disk_get(disk);
180         if (idkp == NULL)
181                 return -ENXIO;
182
183         drive = idkp->drive;
184
185         ide_debug_log(IDE_DBG_FUNC, "Call %s\n", __func__);
186
187         idkp->openers++;
188
189         if ((drive->dev_flags & IDE_DFLAG_REMOVABLE) && idkp->openers == 1) {
190                 drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
191                 /* Just in case */
192
193                 ret = drive->disk_ops->init_media(drive, disk);
194
195                 /*
196                  * Allow O_NDELAY to open a drive without a disk, or with an
197                  * unreadable disk, so that we can get the format capacity
198                  * of the drive or begin the format - Sam
199                  */
200                 if (ret && (mode & FMODE_NDELAY) == 0) {
201                         ret = -EIO;
202                         goto out_put_idkp;
203                 }
204
205                 if ((drive->dev_flags & IDE_DFLAG_WP) && (mode & FMODE_WRITE)) {
206                         ret = -EROFS;
207                         goto out_put_idkp;
208                 }
209
210                 /*
211                  * Ignore the return code from door_lock,
212                  * since the open() has already succeeded,
213                  * and the door_lock is irrelevant at this point.
214                  */
215                 drive->disk_ops->set_doorlock(drive, disk, 1);
216                 drive->dev_flags |= IDE_DFLAG_MEDIA_CHANGED;
217                 check_disk_change(bdev);
218         } else if (drive->dev_flags & IDE_DFLAG_FORMAT_IN_PROGRESS) {
219                 ret = -EBUSY;
220                 goto out_put_idkp;
221         }
222         return 0;
223
224 out_put_idkp:
225         idkp->openers--;
226         ide_disk_put(idkp);
227         return ret;
228 }
229
230 static int ide_gd_release(struct gendisk *disk, fmode_t mode)
231 {
232         struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
233         ide_drive_t *drive = idkp->drive;
234
235         ide_debug_log(IDE_DBG_FUNC, "Call %s\n", __func__);
236
237         if (idkp->openers == 1)
238                 drive->disk_ops->flush(drive);
239
240         if ((drive->dev_flags & IDE_DFLAG_REMOVABLE) && idkp->openers == 1) {
241                 drive->disk_ops->set_doorlock(drive, disk, 0);
242                 drive->dev_flags &= ~IDE_DFLAG_FORMAT_IN_PROGRESS;
243         }
244
245         idkp->openers--;
246
247         ide_disk_put(idkp);
248
249         return 0;
250 }
251
252 static int ide_gd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
253 {
254         struct ide_disk_obj *idkp = ide_drv_g(bdev->bd_disk, ide_disk_obj);
255         ide_drive_t *drive = idkp->drive;
256
257         geo->heads = drive->bios_head;
258         geo->sectors = drive->bios_sect;
259         geo->cylinders = (u16)drive->bios_cyl; /* truncate */
260         return 0;
261 }
262
263 static int ide_gd_media_changed(struct gendisk *disk)
264 {
265         struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
266         ide_drive_t *drive = idkp->drive;
267         int ret;
268
269         /* do not scan partitions twice if this is a removable device */
270         if (drive->dev_flags & IDE_DFLAG_ATTACH) {
271                 drive->dev_flags &= ~IDE_DFLAG_ATTACH;
272                 return 0;
273         }
274
275         ret = !!(drive->dev_flags & IDE_DFLAG_MEDIA_CHANGED);
276         drive->dev_flags &= ~IDE_DFLAG_MEDIA_CHANGED;
277
278         return ret;
279 }
280
281 static int ide_gd_revalidate_disk(struct gendisk *disk)
282 {
283         struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
284         ide_drive_t *drive = idkp->drive;
285
286         if (ide_gd_media_changed(disk))
287                 drive->disk_ops->get_capacity(drive);
288
289         set_capacity(disk, ide_gd_capacity(drive));
290         return 0;
291 }
292
293 static int ide_gd_ioctl(struct block_device *bdev, fmode_t mode,
294                              unsigned int cmd, unsigned long arg)
295 {
296         struct ide_disk_obj *idkp = ide_drv_g(bdev->bd_disk, ide_disk_obj);
297         ide_drive_t *drive = idkp->drive;
298
299         return drive->disk_ops->ioctl(drive, bdev, mode, cmd, arg);
300 }
301
302 static struct block_device_operations ide_gd_ops = {
303         .owner                  = THIS_MODULE,
304         .open                   = ide_gd_open,
305         .release                = ide_gd_release,
306         .locked_ioctl           = ide_gd_ioctl,
307         .getgeo                 = ide_gd_getgeo,
308         .media_changed          = ide_gd_media_changed,
309         .revalidate_disk        = ide_gd_revalidate_disk
310 };
311
312 static int ide_gd_probe(ide_drive_t *drive)
313 {
314         const struct ide_disk_ops *disk_ops = NULL;
315         struct ide_disk_obj *idkp;
316         struct gendisk *g;
317
318         /* strstr("foo", "") is non-NULL */
319         if (!strstr("ide-gd", drive->driver_req))
320                 goto failed;
321
322 #ifdef CONFIG_IDE_GD_ATA
323         if (drive->media == ide_disk)
324                 disk_ops = &ide_ata_disk_ops;
325 #endif
326 #ifdef CONFIG_IDE_GD_ATAPI
327         if (drive->media == ide_floppy)
328                 disk_ops = &ide_atapi_disk_ops;
329 #endif
330         if (disk_ops == NULL)
331                 goto failed;
332
333         if (disk_ops->check(drive, DRV_NAME) == 0) {
334                 printk(KERN_ERR PFX "%s: not supported by this driver\n",
335                         drive->name);
336                 goto failed;
337         }
338
339         idkp = kzalloc(sizeof(*idkp), GFP_KERNEL);
340         if (!idkp) {
341                 printk(KERN_ERR PFX "%s: can't allocate a disk structure\n",
342                         drive->name);
343                 goto failed;
344         }
345
346         g = alloc_disk_node(IDE_DISK_MINORS, hwif_to_node(drive->hwif));
347         if (!g)
348                 goto out_free_idkp;
349
350         ide_init_disk(g, drive);
351
352         kref_init(&idkp->kref);
353
354         idkp->drive = drive;
355         idkp->driver = &ide_gd_driver;
356         idkp->disk = g;
357
358         g->private_data = &idkp->driver;
359
360         drive->driver_data = idkp;
361         drive->debug_mask = debug_mask;
362         drive->disk_ops = disk_ops;
363
364         disk_ops->setup(drive);
365
366         set_capacity(g, ide_gd_capacity(drive));
367
368         g->minors = IDE_DISK_MINORS;
369         g->driverfs_dev = &drive->gendev;
370         g->flags |= GENHD_FL_EXT_DEVT;
371         if (drive->dev_flags & IDE_DFLAG_REMOVABLE)
372                 g->flags = GENHD_FL_REMOVABLE;
373         g->fops = &ide_gd_ops;
374         add_disk(g);
375         return 0;
376
377 out_free_idkp:
378         kfree(idkp);
379 failed:
380         return -ENODEV;
381 }
382
383 static int __init ide_gd_init(void)
384 {
385         printk(KERN_INFO DRV_NAME " driver " IDE_GD_VERSION "\n");
386         return driver_register(&ide_gd_driver.gen_driver);
387 }
388
389 static void __exit ide_gd_exit(void)
390 {
391         driver_unregister(&ide_gd_driver.gen_driver);
392 }
393
394 MODULE_ALIAS("ide:*m-disk*");
395 MODULE_ALIAS("ide-disk");
396 MODULE_ALIAS("ide:*m-floppy*");
397 MODULE_ALIAS("ide-floppy");
398 module_init(ide_gd_init);
399 module_exit(ide_gd_exit);
400 MODULE_LICENSE("GPL");
401 MODULE_DESCRIPTION("generic ATA/ATAPI disk driver");