Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-2.6] / drivers / char / viotape.c
1 /* -*- linux-c -*-
2  *  drivers/char/viotape.c
3  *
4  *  iSeries Virtual Tape
5  *
6  *  Authors: Dave Boutcher <boutcher@us.ibm.com>
7  *           Ryan Arnold <ryanarn@us.ibm.com>
8  *           Colin Devilbiss <devilbis@us.ibm.com>
9  *           Stephen Rothwell
10  *
11  * (C) Copyright 2000-2004 IBM Corporation
12  *
13  * This program is free software;  you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License as
15  * published by the Free Software Foundation; either version 2 of the
16  * License, or (at your option) anyu later version.
17  *
18  * This program is distributed in the hope that it will be useful, but
19  * WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
21  * General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software Foundation,
25  * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26  *
27  * This routine provides access to tape drives owned and managed by an OS/400
28  * partition running on the same box as this Linux partition.
29  *
30  * All tape operations are performed by sending messages back and forth to
31  * the OS/400 partition.  The format of the messages is defined in
32  * iseries/vio.h
33  */
34 #include <linux/module.h>
35 #include <linux/kernel.h>
36 #include <linux/errno.h>
37 #include <linux/init.h>
38 #include <linux/wait.h>
39 #include <linux/spinlock.h>
40 #include <linux/mtio.h>
41 #include <linux/device.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/fs.h>
44 #include <linux/cdev.h>
45 #include <linux/major.h>
46 #include <linux/completion.h>
47 #include <linux/proc_fs.h>
48 #include <linux/seq_file.h>
49
50 #include <asm/uaccess.h>
51 #include <asm/ioctls.h>
52 #include <asm/firmware.h>
53 #include <asm/vio.h>
54 #include <asm/iseries/vio.h>
55 #include <asm/iseries/hv_lp_event.h>
56 #include <asm/iseries/hv_call_event.h>
57 #include <asm/iseries/hv_lp_config.h>
58
59 #define VIOTAPE_VERSION         "1.2"
60 #define VIOTAPE_MAXREQ          1
61
62 #define VIOTAPE_KERN_WARN       KERN_WARNING "viotape: "
63 #define VIOTAPE_KERN_INFO       KERN_INFO "viotape: "
64
65 static int viotape_numdev;
66
67 /*
68  * The minor number follows the conventions of the SCSI tape drives.  The
69  * rewind and mode are encoded in the minor #.  We use this struct to break
70  * them out
71  */
72 struct viot_devinfo_struct {
73         int devno;
74         int mode;
75         int rewind;
76 };
77
78 #define VIOTAPOP_RESET          0
79 #define VIOTAPOP_FSF            1
80 #define VIOTAPOP_BSF            2
81 #define VIOTAPOP_FSR            3
82 #define VIOTAPOP_BSR            4
83 #define VIOTAPOP_WEOF           5
84 #define VIOTAPOP_REW            6
85 #define VIOTAPOP_NOP            7
86 #define VIOTAPOP_EOM            8
87 #define VIOTAPOP_ERASE          9
88 #define VIOTAPOP_SETBLK        10
89 #define VIOTAPOP_SETDENSITY    11
90 #define VIOTAPOP_SETPOS        12
91 #define VIOTAPOP_GETPOS        13
92 #define VIOTAPOP_SETPART       14
93 #define VIOTAPOP_UNLOAD        15
94
95 enum viotaperc {
96         viotape_InvalidRange = 0x0601,
97         viotape_InvalidToken = 0x0602,
98         viotape_DMAError = 0x0603,
99         viotape_UseError = 0x0604,
100         viotape_ReleaseError = 0x0605,
101         viotape_InvalidTape = 0x0606,
102         viotape_InvalidOp = 0x0607,
103         viotape_TapeErr = 0x0608,
104
105         viotape_AllocTimedOut = 0x0640,
106         viotape_BOTEnc = 0x0641,
107         viotape_BlankTape = 0x0642,
108         viotape_BufferEmpty = 0x0643,
109         viotape_CleanCartFound = 0x0644,
110         viotape_CmdNotAllowed = 0x0645,
111         viotape_CmdNotSupported = 0x0646,
112         viotape_DataCheck = 0x0647,
113         viotape_DecompressErr = 0x0648,
114         viotape_DeviceTimeout = 0x0649,
115         viotape_DeviceUnavail = 0x064a,
116         viotape_DeviceBusy = 0x064b,
117         viotape_EndOfMedia = 0x064c,
118         viotape_EndOfTape = 0x064d,
119         viotape_EquipCheck = 0x064e,
120         viotape_InsufficientRs = 0x064f,
121         viotape_InvalidLogBlk = 0x0650,
122         viotape_LengthError = 0x0651,
123         viotape_LibDoorOpen = 0x0652,
124         viotape_LoadFailure = 0x0653,
125         viotape_NotCapable = 0x0654,
126         viotape_NotOperational = 0x0655,
127         viotape_NotReady = 0x0656,
128         viotape_OpCancelled = 0x0657,
129         viotape_PhyLinkErr = 0x0658,
130         viotape_RdyNotBOT = 0x0659,
131         viotape_TapeMark = 0x065a,
132         viotape_WriteProt = 0x065b
133 };
134
135 static const struct vio_error_entry viotape_err_table[] = {
136         { viotape_InvalidRange, EIO, "Internal error" },
137         { viotape_InvalidToken, EIO, "Internal error" },
138         { viotape_DMAError, EIO, "DMA error" },
139         { viotape_UseError, EIO, "Internal error" },
140         { viotape_ReleaseError, EIO, "Internal error" },
141         { viotape_InvalidTape, EIO, "Invalid tape device" },
142         { viotape_InvalidOp, EIO, "Invalid operation" },
143         { viotape_TapeErr, EIO, "Tape error" },
144         { viotape_AllocTimedOut, EBUSY, "Allocate timed out" },
145         { viotape_BOTEnc, EIO, "Beginning of tape encountered" },
146         { viotape_BlankTape, EIO, "Blank tape" },
147         { viotape_BufferEmpty, EIO, "Buffer empty" },
148         { viotape_CleanCartFound, ENOMEDIUM, "Cleaning cartridge found" },
149         { viotape_CmdNotAllowed, EIO, "Command not allowed" },
150         { viotape_CmdNotSupported, EIO, "Command not supported" },
151         { viotape_DataCheck, EIO, "Data check" },
152         { viotape_DecompressErr, EIO, "Decompression error" },
153         { viotape_DeviceTimeout, EBUSY, "Device timeout" },
154         { viotape_DeviceUnavail, EIO, "Device unavailable" },
155         { viotape_DeviceBusy, EBUSY, "Device busy" },
156         { viotape_EndOfMedia, ENOSPC, "End of media" },
157         { viotape_EndOfTape, ENOSPC, "End of tape" },
158         { viotape_EquipCheck, EIO, "Equipment check" },
159         { viotape_InsufficientRs, EOVERFLOW, "Insufficient tape resources" },
160         { viotape_InvalidLogBlk, EIO, "Invalid logical block location" },
161         { viotape_LengthError, EOVERFLOW, "Length error" },
162         { viotape_LibDoorOpen, EBUSY, "Door open" },
163         { viotape_LoadFailure, ENOMEDIUM, "Load failure" },
164         { viotape_NotCapable, EIO, "Not capable" },
165         { viotape_NotOperational, EIO, "Not operational" },
166         { viotape_NotReady, EIO, "Not ready" },
167         { viotape_OpCancelled, EIO, "Operation cancelled" },
168         { viotape_PhyLinkErr, EIO, "Physical link error" },
169         { viotape_RdyNotBOT, EIO, "Ready but not beginning of tape" },
170         { viotape_TapeMark, EIO, "Tape mark" },
171         { viotape_WriteProt, EROFS, "Write protection error" },
172         { 0, 0, NULL },
173 };
174
175 /* Maximum number of tapes we support */
176 #define VIOTAPE_MAX_TAPE        HVMAXARCHITECTEDVIRTUALTAPES
177 #define MAX_PARTITIONS          4
178
179 /* defines for current tape state */
180 #define VIOT_IDLE               0
181 #define VIOT_READING            1
182 #define VIOT_WRITING            2
183
184 /* Our info on the tapes */
185 static struct {
186         const char *rsrcname;
187         const char *type;
188         const char *model;
189 } viotape_unitinfo[VIOTAPE_MAX_TAPE];
190
191 static struct mtget viomtget[VIOTAPE_MAX_TAPE];
192
193 static struct class *tape_class;
194
195 static struct device *tape_device[VIOTAPE_MAX_TAPE];
196
197 /*
198  * maintain the current state of each tape (and partition)
199  * so that we know when to write EOF marks.
200  */
201 static struct {
202         unsigned char   cur_part;
203         unsigned char   part_stat_rwi[MAX_PARTITIONS];
204 } state[VIOTAPE_MAX_TAPE];
205
206 /* We single-thread */
207 static struct semaphore reqSem;
208
209 /*
210  * When we send a request, we use this struct to get the response back
211  * from the interrupt handler
212  */
213 struct op_struct {
214         void                    *buffer;
215         dma_addr_t              dmaaddr;
216         size_t                  count;
217         int                     rc;
218         int                     non_blocking;
219         struct completion       com;
220         struct device           *dev;
221         struct op_struct        *next;
222 };
223
224 static spinlock_t       op_struct_list_lock;
225 static struct op_struct *op_struct_list;
226
227 /* forward declaration to resolve interdependence */
228 static int chg_state(int index, unsigned char new_state, struct file *file);
229
230 /* procfs support */
231 static int proc_viotape_show(struct seq_file *m, void *v)
232 {
233         int i;
234
235         seq_printf(m, "viotape driver version " VIOTAPE_VERSION "\n");
236         for (i = 0; i < viotape_numdev; i++) {
237                 seq_printf(m, "viotape device %d is iSeries resource %10.10s"
238                                 "type %4.4s, model %3.3s\n",
239                                 i, viotape_unitinfo[i].rsrcname,
240                                 viotape_unitinfo[i].type,
241                                 viotape_unitinfo[i].model);
242         }
243         return 0;
244 }
245
246 static int proc_viotape_open(struct inode *inode, struct file *file)
247 {
248         return single_open(file, proc_viotape_show, NULL);
249 }
250
251 static const struct file_operations proc_viotape_operations = {
252         .owner          = THIS_MODULE,
253         .open           = proc_viotape_open,
254         .read           = seq_read,
255         .llseek         = seq_lseek,
256         .release        = single_release,
257 };
258
259 /* Decode the device minor number into its parts */
260 void get_dev_info(struct inode *ino, struct viot_devinfo_struct *devi)
261 {
262         devi->devno = iminor(ino) & 0x1F;
263         devi->mode = (iminor(ino) & 0x60) >> 5;
264         /* if bit is set in the minor, do _not_ rewind automatically */
265         devi->rewind = (iminor(ino) & 0x80) == 0;
266 }
267
268 /* This is called only from the exit and init paths, so no need for locking */
269 static void clear_op_struct_pool(void)
270 {
271         while (op_struct_list) {
272                 struct op_struct *toFree = op_struct_list;
273                 op_struct_list = op_struct_list->next;
274                 kfree(toFree);
275         }
276 }
277
278 /* Likewise, this is only called from the init path */
279 static int add_op_structs(int structs)
280 {
281         int i;
282
283         for (i = 0; i < structs; ++i) {
284                 struct op_struct *new_struct =
285                         kmalloc(sizeof(*new_struct), GFP_KERNEL);
286                 if (!new_struct) {
287                         clear_op_struct_pool();
288                         return -ENOMEM;
289                 }
290                 new_struct->next = op_struct_list;
291                 op_struct_list = new_struct;
292         }
293         return 0;
294 }
295
296 /* Allocate an op structure from our pool */
297 static struct op_struct *get_op_struct(void)
298 {
299         struct op_struct *retval;
300         unsigned long flags;
301
302         spin_lock_irqsave(&op_struct_list_lock, flags);
303         retval = op_struct_list;
304         if (retval)
305                 op_struct_list = retval->next;
306         spin_unlock_irqrestore(&op_struct_list_lock, flags);
307         if (retval) {
308                 memset(retval, 0, sizeof(*retval));
309                 init_completion(&retval->com);
310         }
311
312         return retval;
313 }
314
315 /* Return an op structure to our pool */
316 static void free_op_struct(struct op_struct *op_struct)
317 {
318         unsigned long flags;
319
320         spin_lock_irqsave(&op_struct_list_lock, flags);
321         op_struct->next = op_struct_list;
322         op_struct_list = op_struct;
323         spin_unlock_irqrestore(&op_struct_list_lock, flags);
324 }
325
326 /* Map our tape return codes to errno values */
327 int tape_rc_to_errno(int tape_rc, char *operation, int tapeno)
328 {
329         const struct vio_error_entry *err;
330
331         if (tape_rc == 0)
332                 return 0;
333
334         err = vio_lookup_rc(viotape_err_table, tape_rc);
335         printk(VIOTAPE_KERN_WARN "error(%s) 0x%04x on Device %d (%-10s): %s\n",
336                         operation, tape_rc, tapeno,
337                         viotape_unitinfo[tapeno].rsrcname, err->msg);
338         return -err->errno;
339 }
340
341 /* Write */
342 static ssize_t viotap_write(struct file *file, const char *buf,
343                 size_t count, loff_t * ppos)
344 {
345         HvLpEvent_Rc hvrc;
346         unsigned short flags = file->f_flags;
347         int noblock = ((flags & O_NONBLOCK) != 0);
348         ssize_t ret;
349         struct viot_devinfo_struct devi;
350         struct op_struct *op = get_op_struct();
351
352         if (op == NULL)
353                 return -ENOMEM;
354
355         get_dev_info(file->f_path.dentry->d_inode, &devi);
356
357         /*
358          * We need to make sure we can send a request.  We use
359          * a semaphore to keep track of # requests in use.  If
360          * we are non-blocking, make sure we don't block on the
361          * semaphore
362          */
363         if (noblock) {
364                 if (down_trylock(&reqSem)) {
365                         ret = -EWOULDBLOCK;
366                         goto free_op;
367                 }
368         } else
369                 down(&reqSem);
370
371         /* Allocate a DMA buffer */
372         op->dev = tape_device[devi.devno];
373         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
374                         GFP_ATOMIC);
375
376         if (op->buffer == NULL) {
377                 printk(VIOTAPE_KERN_WARN
378                                 "error allocating dma buffer for len %ld\n",
379                                 count);
380                 ret = -EFAULT;
381                 goto up_sem;
382         }
383
384         /* Copy the data into the buffer */
385         if (copy_from_user(op->buffer, buf, count)) {
386                 printk(VIOTAPE_KERN_WARN "tape: error on copy from user\n");
387                 ret = -EFAULT;
388                 goto free_dma;
389         }
390
391         op->non_blocking = noblock;
392         init_completion(&op->com);
393         op->count = count;
394
395         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
396                         HvLpEvent_Type_VirtualIo,
397                         viomajorsubtype_tape | viotapewrite,
398                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
399                         viopath_sourceinst(viopath_hostLp),
400                         viopath_targetinst(viopath_hostLp),
401                         (u64)(unsigned long)op, VIOVERSION << 16,
402                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
403         if (hvrc != HvLpEvent_Rc_Good) {
404                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
405                                 (int)hvrc);
406                 ret = -EIO;
407                 goto free_dma;
408         }
409
410         if (noblock)
411                 return count;
412
413         wait_for_completion(&op->com);
414
415         if (op->rc)
416                 ret = tape_rc_to_errno(op->rc, "write", devi.devno);
417         else {
418                 chg_state(devi.devno, VIOT_WRITING, file);
419                 ret = op->count;
420         }
421
422 free_dma:
423         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
424 up_sem:
425         up(&reqSem);
426 free_op:
427         free_op_struct(op);
428         return ret;
429 }
430
431 /* read */
432 static ssize_t viotap_read(struct file *file, char *buf, size_t count,
433                 loff_t *ptr)
434 {
435         HvLpEvent_Rc hvrc;
436         unsigned short flags = file->f_flags;
437         struct op_struct *op = get_op_struct();
438         int noblock = ((flags & O_NONBLOCK) != 0);
439         ssize_t ret;
440         struct viot_devinfo_struct devi;
441
442         if (op == NULL)
443                 return -ENOMEM;
444
445         get_dev_info(file->f_path.dentry->d_inode, &devi);
446
447         /*
448          * We need to make sure we can send a request.  We use
449          * a semaphore to keep track of # requests in use.  If
450          * we are non-blocking, make sure we don't block on the
451          * semaphore
452          */
453         if (noblock) {
454                 if (down_trylock(&reqSem)) {
455                         ret = -EWOULDBLOCK;
456                         goto free_op;
457                 }
458         } else
459                 down(&reqSem);
460
461         chg_state(devi.devno, VIOT_READING, file);
462
463         /* Allocate a DMA buffer */
464         op->dev = tape_device[devi.devno];
465         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
466                         GFP_ATOMIC);
467         if (op->buffer == NULL) {
468                 ret = -EFAULT;
469                 goto up_sem;
470         }
471
472         op->count = count;
473         init_completion(&op->com);
474
475         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
476                         HvLpEvent_Type_VirtualIo,
477                         viomajorsubtype_tape | viotaperead,
478                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
479                         viopath_sourceinst(viopath_hostLp),
480                         viopath_targetinst(viopath_hostLp),
481                         (u64)(unsigned long)op, VIOVERSION << 16,
482                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
483         if (hvrc != HvLpEvent_Rc_Good) {
484                 printk(VIOTAPE_KERN_WARN "tape hv error on op %d\n",
485                                 (int)hvrc);
486                 ret = -EIO;
487                 goto free_dma;
488         }
489
490         wait_for_completion(&op->com);
491
492         if (op->rc)
493                 ret = tape_rc_to_errno(op->rc, "read", devi.devno);
494         else {
495                 ret = op->count;
496                 if (ret && copy_to_user(buf, op->buffer, ret)) {
497                         printk(VIOTAPE_KERN_WARN "error on copy_to_user\n");
498                         ret = -EFAULT;
499                 }
500         }
501
502 free_dma:
503         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
504 up_sem:
505         up(&reqSem);
506 free_op:
507         free_op_struct(op);
508         return ret;
509 }
510
511 /* ioctl */
512 static int viotap_ioctl(struct inode *inode, struct file *file,
513                 unsigned int cmd, unsigned long arg)
514 {
515         HvLpEvent_Rc hvrc;
516         int ret;
517         struct viot_devinfo_struct devi;
518         struct mtop mtc;
519         u32 myOp;
520         struct op_struct *op = get_op_struct();
521
522         if (op == NULL)
523                 return -ENOMEM;
524
525         get_dev_info(file->f_path.dentry->d_inode, &devi);
526
527         down(&reqSem);
528
529         ret = -EINVAL;
530
531         switch (cmd) {
532         case MTIOCTOP:
533                 ret = -EFAULT;
534                 /*
535                  * inode is null if and only if we (the kernel)
536                  * made the request
537                  */
538                 if (inode == NULL)
539                         memcpy(&mtc, (void *) arg, sizeof(struct mtop));
540                 else if (copy_from_user((char *)&mtc, (char *)arg,
541                                         sizeof(struct mtop)))
542                         goto free_op;
543
544                 ret = -EIO;
545                 switch (mtc.mt_op) {
546                 case MTRESET:
547                         myOp = VIOTAPOP_RESET;
548                         break;
549                 case MTFSF:
550                         myOp = VIOTAPOP_FSF;
551                         break;
552                 case MTBSF:
553                         myOp = VIOTAPOP_BSF;
554                         break;
555                 case MTFSR:
556                         myOp = VIOTAPOP_FSR;
557                         break;
558                 case MTBSR:
559                         myOp = VIOTAPOP_BSR;
560                         break;
561                 case MTWEOF:
562                         myOp = VIOTAPOP_WEOF;
563                         break;
564                 case MTREW:
565                         myOp = VIOTAPOP_REW;
566                         break;
567                 case MTNOP:
568                         myOp = VIOTAPOP_NOP;
569                         break;
570                 case MTEOM:
571                         myOp = VIOTAPOP_EOM;
572                         break;
573                 case MTERASE:
574                         myOp = VIOTAPOP_ERASE;
575                         break;
576                 case MTSETBLK:
577                         myOp = VIOTAPOP_SETBLK;
578                         break;
579                 case MTSETDENSITY:
580                         myOp = VIOTAPOP_SETDENSITY;
581                         break;
582                 case MTTELL:
583                         myOp = VIOTAPOP_GETPOS;
584                         break;
585                 case MTSEEK:
586                         myOp = VIOTAPOP_SETPOS;
587                         break;
588                 case MTSETPART:
589                         myOp = VIOTAPOP_SETPART;
590                         break;
591                 case MTOFFL:
592                         myOp = VIOTAPOP_UNLOAD;
593                         break;
594                 default:
595                         printk(VIOTAPE_KERN_WARN "MTIOCTOP called "
596                                         "with invalid op 0x%x\n", mtc.mt_op);
597                         goto free_op;
598                 }
599
600                 /*
601                  * if we moved the head, we are no longer
602                  * reading or writing
603                  */
604                 switch (mtc.mt_op) {
605                 case MTFSF:
606                 case MTBSF:
607                 case MTFSR:
608                 case MTBSR:
609                 case MTTELL:
610                 case MTSEEK:
611                 case MTREW:
612                         chg_state(devi.devno, VIOT_IDLE, file);
613                 }
614
615                 init_completion(&op->com);
616                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
617                                 HvLpEvent_Type_VirtualIo,
618                                 viomajorsubtype_tape | viotapeop,
619                                 HvLpEvent_AckInd_DoAck,
620                                 HvLpEvent_AckType_ImmediateAck,
621                                 viopath_sourceinst(viopath_hostLp),
622                                 viopath_targetinst(viopath_hostLp),
623                                 (u64)(unsigned long)op,
624                                 VIOVERSION << 16,
625                                 ((u64)devi.devno << 48), 0,
626                                 (((u64)myOp) << 32) | mtc.mt_count, 0);
627                 if (hvrc != HvLpEvent_Rc_Good) {
628                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
629                                         (int)hvrc);
630                         goto free_op;
631                 }
632                 wait_for_completion(&op->com);
633                 ret = tape_rc_to_errno(op->rc, "tape operation", devi.devno);
634                 goto free_op;
635
636         case MTIOCGET:
637                 ret = -EIO;
638                 init_completion(&op->com);
639                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
640                                 HvLpEvent_Type_VirtualIo,
641                                 viomajorsubtype_tape | viotapegetstatus,
642                                 HvLpEvent_AckInd_DoAck,
643                                 HvLpEvent_AckType_ImmediateAck,
644                                 viopath_sourceinst(viopath_hostLp),
645                                 viopath_targetinst(viopath_hostLp),
646                                 (u64)(unsigned long)op, VIOVERSION << 16,
647                                 ((u64)devi.devno << 48), 0, 0, 0);
648                 if (hvrc != HvLpEvent_Rc_Good) {
649                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
650                                         (int)hvrc);
651                         goto free_op;
652                 }
653                 wait_for_completion(&op->com);
654
655                 /* Operation is complete - grab the error code */
656                 ret = tape_rc_to_errno(op->rc, "get status", devi.devno);
657                 free_op_struct(op);
658                 up(&reqSem);
659
660                 if ((ret == 0) && copy_to_user((void *)arg,
661                                         &viomtget[devi.devno],
662                                         sizeof(viomtget[0])))
663                         ret = -EFAULT;
664                 return ret;
665         case MTIOCPOS:
666                 printk(VIOTAPE_KERN_WARN "Got an (unsupported) MTIOCPOS\n");
667                 break;
668         default:
669                 printk(VIOTAPE_KERN_WARN "got an unsupported ioctl 0x%0x\n",
670                                 cmd);
671                 break;
672         }
673
674 free_op:
675         free_op_struct(op);
676         up(&reqSem);
677         return ret;
678 }
679
680 static int viotap_open(struct inode *inode, struct file *file)
681 {
682         HvLpEvent_Rc hvrc;
683         struct viot_devinfo_struct devi;
684         int ret;
685         struct op_struct *op = get_op_struct();
686
687         if (op == NULL)
688                 return -ENOMEM;
689
690         get_dev_info(file->f_path.dentry->d_inode, &devi);
691
692         /* Note: We currently only support one mode! */
693         if ((devi.devno >= viotape_numdev) || (devi.mode)) {
694                 ret = -ENODEV;
695                 goto free_op;
696         }
697
698         init_completion(&op->com);
699
700         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
701                         HvLpEvent_Type_VirtualIo,
702                         viomajorsubtype_tape | viotapeopen,
703                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
704                         viopath_sourceinst(viopath_hostLp),
705                         viopath_targetinst(viopath_hostLp),
706                         (u64)(unsigned long)op, VIOVERSION << 16,
707                         ((u64)devi.devno << 48), 0, 0, 0);
708         if (hvrc != 0) {
709                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
710                                 (int) hvrc);
711                 ret = -EIO;
712                 goto free_op;
713         }
714
715         wait_for_completion(&op->com);
716         ret = tape_rc_to_errno(op->rc, "open", devi.devno);
717
718 free_op:
719         free_op_struct(op);
720         return ret;
721 }
722
723
724 static int viotap_release(struct inode *inode, struct file *file)
725 {
726         HvLpEvent_Rc hvrc;
727         struct viot_devinfo_struct devi;
728         int ret = 0;
729         struct op_struct *op = get_op_struct();
730
731         if (op == NULL)
732                 return -ENOMEM;
733         init_completion(&op->com);
734
735         get_dev_info(file->f_path.dentry->d_inode, &devi);
736
737         if (devi.devno >= viotape_numdev) {
738                 ret = -ENODEV;
739                 goto free_op;
740         }
741
742         chg_state(devi.devno, VIOT_IDLE, file);
743
744         if (devi.rewind) {
745                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
746                                 HvLpEvent_Type_VirtualIo,
747                                 viomajorsubtype_tape | viotapeop,
748                                 HvLpEvent_AckInd_DoAck,
749                                 HvLpEvent_AckType_ImmediateAck,
750                                 viopath_sourceinst(viopath_hostLp),
751                                 viopath_targetinst(viopath_hostLp),
752                                 (u64)(unsigned long)op, VIOVERSION << 16,
753                                 ((u64)devi.devno << 48), 0,
754                                 ((u64)VIOTAPOP_REW) << 32, 0);
755                 wait_for_completion(&op->com);
756
757                 tape_rc_to_errno(op->rc, "rewind", devi.devno);
758         }
759
760         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
761                         HvLpEvent_Type_VirtualIo,
762                         viomajorsubtype_tape | viotapeclose,
763                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
764                         viopath_sourceinst(viopath_hostLp),
765                         viopath_targetinst(viopath_hostLp),
766                         (u64)(unsigned long)op, VIOVERSION << 16,
767                         ((u64)devi.devno << 48), 0, 0, 0);
768         if (hvrc != 0) {
769                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
770                                 (int) hvrc);
771                 ret = -EIO;
772                 goto free_op;
773         }
774
775         wait_for_completion(&op->com);
776
777         if (op->rc)
778                 printk(VIOTAPE_KERN_WARN "close failed\n");
779
780 free_op:
781         free_op_struct(op);
782         return ret;
783 }
784
785 const struct file_operations viotap_fops = {
786         .owner =        THIS_MODULE,
787         .read =         viotap_read,
788         .write =        viotap_write,
789         .ioctl =        viotap_ioctl,
790         .open =         viotap_open,
791         .release =      viotap_release,
792 };
793
794 /* Handle interrupt events for tape */
795 static void vioHandleTapeEvent(struct HvLpEvent *event)
796 {
797         int tapeminor;
798         struct op_struct *op;
799         struct viotapelpevent *tevent = (struct viotapelpevent *)event;
800
801         if (event == NULL) {
802                 /* Notification that a partition went away! */
803                 if (!viopath_isactive(viopath_hostLp)) {
804                         /* TODO! Clean up */
805                 }
806                 return;
807         }
808
809         tapeminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
810         op = (struct op_struct *)event->xCorrelationToken;
811         switch (tapeminor) {
812         case viotapeopen:
813         case viotapeclose:
814                 op->rc = tevent->sub_type_result;
815                 complete(&op->com);
816                 break;
817         case viotaperead:
818                 op->rc = tevent->sub_type_result;
819                 op->count = tevent->len;
820                 complete(&op->com);
821                 break;
822         case viotapewrite:
823                 if (op->non_blocking) {
824                         dma_free_coherent(op->dev, op->count,
825                                         op->buffer, op->dmaaddr);
826                         free_op_struct(op);
827                         up(&reqSem);
828                 } else {
829                         op->rc = tevent->sub_type_result;
830                         op->count = tevent->len;
831                         complete(&op->com);
832                 }
833                 break;
834         case viotapeop:
835         case viotapegetpos:
836         case viotapesetpos:
837         case viotapegetstatus:
838                 if (op) {
839                         op->count = tevent->u.op.count;
840                         op->rc = tevent->sub_type_result;
841                         if (!op->non_blocking)
842                                 complete(&op->com);
843                 }
844                 break;
845         default:
846                 printk(VIOTAPE_KERN_WARN "weird ack\n");
847         }
848 }
849
850 static int viotape_probe(struct vio_dev *vdev, const struct vio_device_id *id)
851 {
852         int i = vdev->unit_address;
853         int j;
854         struct device_node *node = vdev->dev.archdata.of_node;
855
856         if (i > VIOTAPE_MAX_TAPE)
857                 return -ENODEV;
858         if (!node)
859                 return -ENODEV;
860
861         if (i >= viotape_numdev)
862                 viotape_numdev = i + 1;
863
864         tape_device[i] = &vdev->dev;
865         viotape_unitinfo[i].rsrcname = of_get_property(node,
866                                         "linux,vio_rsrcname", NULL);
867         viotape_unitinfo[i].type = of_get_property(node, "linux,vio_type",
868                                         NULL);
869         viotape_unitinfo[i].model = of_get_property(node, "linux,vio_model",
870                                         NULL);
871
872         state[i].cur_part = 0;
873         for (j = 0; j < MAX_PARTITIONS; ++j)
874                 state[i].part_stat_rwi[j] = VIOT_IDLE;
875         device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i),
876                         "iseries!vt%d", i);
877         device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i | 0x80),
878                         "iseries!nvt%d", i);
879         printk(VIOTAPE_KERN_INFO "tape iseries/vt%d is iSeries "
880                         "resource %10.10s type %4.4s, model %3.3s\n",
881                         i, viotape_unitinfo[i].rsrcname,
882                         viotape_unitinfo[i].type, viotape_unitinfo[i].model);
883         return 0;
884 }
885
886 static int viotape_remove(struct vio_dev *vdev)
887 {
888         int i = vdev->unit_address;
889
890         device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i | 0x80));
891         device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i));
892         return 0;
893 }
894
895 /**
896  * viotape_device_table: Used by vio.c to match devices that we
897  * support.
898  */
899 static struct vio_device_id viotape_device_table[] __devinitdata = {
900         { "byte", "IBM,iSeries-viotape" },
901         { "", "" }
902 };
903 MODULE_DEVICE_TABLE(vio, viotape_device_table);
904
905 static struct vio_driver viotape_driver = {
906         .id_table = viotape_device_table,
907         .probe = viotape_probe,
908         .remove = viotape_remove,
909         .driver = {
910                 .name = "viotape",
911                 .owner = THIS_MODULE,
912         }
913 };
914
915
916 int __init viotap_init(void)
917 {
918         int ret;
919
920         if (!firmware_has_feature(FW_FEATURE_ISERIES))
921                 return -ENODEV;
922
923         op_struct_list = NULL;
924         if ((ret = add_op_structs(VIOTAPE_MAXREQ)) < 0) {
925                 printk(VIOTAPE_KERN_WARN "couldn't allocate op structs\n");
926                 return ret;
927         }
928         spin_lock_init(&op_struct_list_lock);
929
930         sema_init(&reqSem, VIOTAPE_MAXREQ);
931
932         if (viopath_hostLp == HvLpIndexInvalid) {
933                 vio_set_hostlp();
934                 if (viopath_hostLp == HvLpIndexInvalid) {
935                         ret = -ENODEV;
936                         goto clear_op;
937                 }
938         }
939
940         ret = viopath_open(viopath_hostLp, viomajorsubtype_tape,
941                         VIOTAPE_MAXREQ + 2);
942         if (ret) {
943                 printk(VIOTAPE_KERN_WARN
944                                 "error on viopath_open to hostlp %d\n", ret);
945                 ret = -EIO;
946                 goto clear_op;
947         }
948
949         printk(VIOTAPE_KERN_INFO "vers " VIOTAPE_VERSION
950                         ", hosting partition %d\n", viopath_hostLp);
951
952         vio_setHandler(viomajorsubtype_tape, vioHandleTapeEvent);
953
954         ret = register_chrdev(VIOTAPE_MAJOR, "viotape", &viotap_fops);
955         if (ret < 0) {
956                 printk(VIOTAPE_KERN_WARN "Error registering viotape device\n");
957                 goto clear_handler;
958         }
959
960         tape_class = class_create(THIS_MODULE, "tape");
961         if (IS_ERR(tape_class)) {
962                 printk(VIOTAPE_KERN_WARN "Unable to allocat class\n");
963                 ret = PTR_ERR(tape_class);
964                 goto unreg_chrdev;
965         }
966
967         ret = vio_register_driver(&viotape_driver);
968         if (ret)
969                 goto unreg_class;
970
971         proc_create("iSeries/viotape", S_IFREG|S_IRUGO, NULL,
972                     &proc_viotape_operations);
973
974         return 0;
975
976 unreg_class:
977         class_destroy(tape_class);
978 unreg_chrdev:
979         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
980 clear_handler:
981         vio_clearHandler(viomajorsubtype_tape);
982         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
983 clear_op:
984         clear_op_struct_pool();
985         return ret;
986 }
987
988 /* Give a new state to the tape object */
989 static int chg_state(int index, unsigned char new_state, struct file *file)
990 {
991         unsigned char *cur_state =
992             &state[index].part_stat_rwi[state[index].cur_part];
993         int rc = 0;
994
995         /* if the same state, don't bother */
996         if (*cur_state == new_state)
997                 return 0;
998
999         /* write an EOF if changing from writing to some other state */
1000         if (*cur_state == VIOT_WRITING) {
1001                 struct mtop write_eof = { MTWEOF, 1 };
1002
1003                 rc = viotap_ioctl(NULL, file, MTIOCTOP,
1004                                   (unsigned long)&write_eof);
1005         }
1006         *cur_state = new_state;
1007         return rc;
1008 }
1009
1010 /* Cleanup */
1011 static void __exit viotap_exit(void)
1012 {
1013         remove_proc_entry("iSeries/viotape", NULL);
1014         vio_unregister_driver(&viotape_driver);
1015         class_destroy(tape_class);
1016         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1017         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1018         vio_clearHandler(viomajorsubtype_tape);
1019         clear_op_struct_pool();
1020 }
1021
1022 MODULE_LICENSE("GPL");
1023 module_init(viotap_init);
1024 module_exit(viotap_exit);