Merge branch 'master' of /home/trondmy/kernel/linux-2.6/
[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 <sfr@au1.ibm.com>
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/config.h>
35 #include <linux/module.h>
36 #include <linux/kernel.h>
37 #include <linux/errno.h>
38 #include <linux/init.h>
39 #include <linux/wait.h>
40 #include <linux/spinlock.h>
41 #include <linux/mtio.h>
42 #include <linux/device.h>
43 #include <linux/dma-mapping.h>
44 #include <linux/fs.h>
45 #include <linux/cdev.h>
46 #include <linux/devfs_fs_kernel.h>
47 #include <linux/major.h>
48 #include <linux/completion.h>
49 #include <linux/proc_fs.h>
50 #include <linux/seq_file.h>
51
52 #include <asm/uaccess.h>
53 #include <asm/ioctls.h>
54
55 #include <asm/vio.h>
56 #include <asm/iseries/vio.h>
57 #include <asm/iseries/hv_lp_event.h>
58 #include <asm/iseries/hv_call_event.h>
59 #include <asm/iseries/hv_lp_config.h>
60
61 #define VIOTAPE_VERSION         "1.2"
62 #define VIOTAPE_MAXREQ          1
63
64 #define VIOTAPE_KERN_WARN       KERN_WARNING "viotape: "
65 #define VIOTAPE_KERN_INFO       KERN_INFO "viotape: "
66
67 static int viotape_numdev;
68
69 /*
70  * The minor number follows the conventions of the SCSI tape drives.  The
71  * rewind and mode are encoded in the minor #.  We use this struct to break
72  * them out
73  */
74 struct viot_devinfo_struct {
75         int devno;
76         int mode;
77         int rewind;
78 };
79
80 #define VIOTAPOP_RESET          0
81 #define VIOTAPOP_FSF            1
82 #define VIOTAPOP_BSF            2
83 #define VIOTAPOP_FSR            3
84 #define VIOTAPOP_BSR            4
85 #define VIOTAPOP_WEOF           5
86 #define VIOTAPOP_REW            6
87 #define VIOTAPOP_NOP            7
88 #define VIOTAPOP_EOM            8
89 #define VIOTAPOP_ERASE          9
90 #define VIOTAPOP_SETBLK        10
91 #define VIOTAPOP_SETDENSITY    11
92 #define VIOTAPOP_SETPOS        12
93 #define VIOTAPOP_GETPOS        13
94 #define VIOTAPOP_SETPART       14
95 #define VIOTAPOP_UNLOAD        15
96
97 struct viotapelpevent {
98         struct HvLpEvent event;
99         u32 reserved;
100         u16 version;
101         u16 sub_type_result;
102         u16 tape;
103         u16 flags;
104         u32 token;
105         u64 len;
106         union {
107                 struct {
108                         u32 tape_op;
109                         u32 count;
110                 } op;
111                 struct {
112                         u32 type;
113                         u32 resid;
114                         u32 dsreg;
115                         u32 gstat;
116                         u32 erreg;
117                         u32 file_no;
118                         u32 block_no;
119                 } get_status;
120                 struct {
121                         u32 block_no;
122                 } get_pos;
123         } u;
124 };
125
126 enum viotapesubtype {
127         viotapeopen = 0x0001,
128         viotapeclose = 0x0002,
129         viotaperead = 0x0003,
130         viotapewrite = 0x0004,
131         viotapegetinfo = 0x0005,
132         viotapeop = 0x0006,
133         viotapegetpos = 0x0007,
134         viotapesetpos = 0x0008,
135         viotapegetstatus = 0x0009
136 };
137
138 enum viotaperc {
139         viotape_InvalidRange = 0x0601,
140         viotape_InvalidToken = 0x0602,
141         viotape_DMAError = 0x0603,
142         viotape_UseError = 0x0604,
143         viotape_ReleaseError = 0x0605,
144         viotape_InvalidTape = 0x0606,
145         viotape_InvalidOp = 0x0607,
146         viotape_TapeErr = 0x0608,
147
148         viotape_AllocTimedOut = 0x0640,
149         viotape_BOTEnc = 0x0641,
150         viotape_BlankTape = 0x0642,
151         viotape_BufferEmpty = 0x0643,
152         viotape_CleanCartFound = 0x0644,
153         viotape_CmdNotAllowed = 0x0645,
154         viotape_CmdNotSupported = 0x0646,
155         viotape_DataCheck = 0x0647,
156         viotape_DecompressErr = 0x0648,
157         viotape_DeviceTimeout = 0x0649,
158         viotape_DeviceUnavail = 0x064a,
159         viotape_DeviceBusy = 0x064b,
160         viotape_EndOfMedia = 0x064c,
161         viotape_EndOfTape = 0x064d,
162         viotape_EquipCheck = 0x064e,
163         viotape_InsufficientRs = 0x064f,
164         viotape_InvalidLogBlk = 0x0650,
165         viotape_LengthError = 0x0651,
166         viotape_LibDoorOpen = 0x0652,
167         viotape_LoadFailure = 0x0653,
168         viotape_NotCapable = 0x0654,
169         viotape_NotOperational = 0x0655,
170         viotape_NotReady = 0x0656,
171         viotape_OpCancelled = 0x0657,
172         viotape_PhyLinkErr = 0x0658,
173         viotape_RdyNotBOT = 0x0659,
174         viotape_TapeMark = 0x065a,
175         viotape_WriteProt = 0x065b
176 };
177
178 static const struct vio_error_entry viotape_err_table[] = {
179         { viotape_InvalidRange, EIO, "Internal error" },
180         { viotape_InvalidToken, EIO, "Internal error" },
181         { viotape_DMAError, EIO, "DMA error" },
182         { viotape_UseError, EIO, "Internal error" },
183         { viotape_ReleaseError, EIO, "Internal error" },
184         { viotape_InvalidTape, EIO, "Invalid tape device" },
185         { viotape_InvalidOp, EIO, "Invalid operation" },
186         { viotape_TapeErr, EIO, "Tape error" },
187         { viotape_AllocTimedOut, EBUSY, "Allocate timed out" },
188         { viotape_BOTEnc, EIO, "Beginning of tape encountered" },
189         { viotape_BlankTape, EIO, "Blank tape" },
190         { viotape_BufferEmpty, EIO, "Buffer empty" },
191         { viotape_CleanCartFound, ENOMEDIUM, "Cleaning cartridge found" },
192         { viotape_CmdNotAllowed, EIO, "Command not allowed" },
193         { viotape_CmdNotSupported, EIO, "Command not supported" },
194         { viotape_DataCheck, EIO, "Data check" },
195         { viotape_DecompressErr, EIO, "Decompression error" },
196         { viotape_DeviceTimeout, EBUSY, "Device timeout" },
197         { viotape_DeviceUnavail, EIO, "Device unavailable" },
198         { viotape_DeviceBusy, EBUSY, "Device busy" },
199         { viotape_EndOfMedia, ENOSPC, "End of media" },
200         { viotape_EndOfTape, ENOSPC, "End of tape" },
201         { viotape_EquipCheck, EIO, "Equipment check" },
202         { viotape_InsufficientRs, EOVERFLOW, "Insufficient tape resources" },
203         { viotape_InvalidLogBlk, EIO, "Invalid logical block location" },
204         { viotape_LengthError, EOVERFLOW, "Length error" },
205         { viotape_LibDoorOpen, EBUSY, "Door open" },
206         { viotape_LoadFailure, ENOMEDIUM, "Load failure" },
207         { viotape_NotCapable, EIO, "Not capable" },
208         { viotape_NotOperational, EIO, "Not operational" },
209         { viotape_NotReady, EIO, "Not ready" },
210         { viotape_OpCancelled, EIO, "Operation cancelled" },
211         { viotape_PhyLinkErr, EIO, "Physical link error" },
212         { viotape_RdyNotBOT, EIO, "Ready but not beginning of tape" },
213         { viotape_TapeMark, EIO, "Tape mark" },
214         { viotape_WriteProt, EROFS, "Write protection error" },
215         { 0, 0, NULL },
216 };
217
218 /* Maximum number of tapes we support */
219 #define VIOTAPE_MAX_TAPE        HVMAXARCHITECTEDVIRTUALTAPES
220 #define MAX_PARTITIONS          4
221
222 /* defines for current tape state */
223 #define VIOT_IDLE               0
224 #define VIOT_READING            1
225 #define VIOT_WRITING            2
226
227 /* Our info on the tapes */
228 struct tape_descr {
229         char rsrcname[10];
230         char type[4];
231         char model[3];
232 };
233
234 static struct tape_descr *viotape_unitinfo;
235 static dma_addr_t viotape_unitinfo_token;
236
237 static struct mtget viomtget[VIOTAPE_MAX_TAPE];
238
239 static struct class *tape_class;
240
241 static struct device *tape_device[VIOTAPE_MAX_TAPE];
242
243 /*
244  * maintain the current state of each tape (and partition)
245  * so that we know when to write EOF marks.
246  */
247 static struct {
248         unsigned char   cur_part;
249         int             dev_handle;
250         unsigned char   part_stat_rwi[MAX_PARTITIONS];
251 } state[VIOTAPE_MAX_TAPE];
252
253 /* We single-thread */
254 static struct semaphore reqSem;
255
256 /*
257  * When we send a request, we use this struct to get the response back
258  * from the interrupt handler
259  */
260 struct op_struct {
261         void                    *buffer;
262         dma_addr_t              dmaaddr;
263         size_t                  count;
264         int                     rc;
265         int                     non_blocking;
266         struct completion       com;
267         struct device           *dev;
268         struct op_struct        *next;
269 };
270
271 static spinlock_t       op_struct_list_lock;
272 static struct op_struct *op_struct_list;
273
274 /* forward declaration to resolve interdependence */
275 static int chg_state(int index, unsigned char new_state, struct file *file);
276
277 /* procfs support */
278 static int proc_viotape_show(struct seq_file *m, void *v)
279 {
280         int i;
281
282         seq_printf(m, "viotape driver version " VIOTAPE_VERSION "\n");
283         for (i = 0; i < viotape_numdev; i++) {
284                 seq_printf(m, "viotape device %d is iSeries resource %10.10s"
285                                 "type %4.4s, model %3.3s\n",
286                                 i, viotape_unitinfo[i].rsrcname,
287                                 viotape_unitinfo[i].type,
288                                 viotape_unitinfo[i].model);
289         }
290         return 0;
291 }
292
293 static int proc_viotape_open(struct inode *inode, struct file *file)
294 {
295         return single_open(file, proc_viotape_show, NULL);
296 }
297
298 static struct file_operations proc_viotape_operations = {
299         .open           = proc_viotape_open,
300         .read           = seq_read,
301         .llseek         = seq_lseek,
302         .release        = single_release,
303 };
304
305 /* Decode the device minor number into its parts */
306 void get_dev_info(struct inode *ino, struct viot_devinfo_struct *devi)
307 {
308         devi->devno = iminor(ino) & 0x1F;
309         devi->mode = (iminor(ino) & 0x60) >> 5;
310         /* if bit is set in the minor, do _not_ rewind automatically */
311         devi->rewind = (iminor(ino) & 0x80) == 0;
312 }
313
314 /* This is called only from the exit and init paths, so no need for locking */
315 static void clear_op_struct_pool(void)
316 {
317         while (op_struct_list) {
318                 struct op_struct *toFree = op_struct_list;
319                 op_struct_list = op_struct_list->next;
320                 kfree(toFree);
321         }
322 }
323
324 /* Likewise, this is only called from the init path */
325 static int add_op_structs(int structs)
326 {
327         int i;
328
329         for (i = 0; i < structs; ++i) {
330                 struct op_struct *new_struct =
331                         kmalloc(sizeof(*new_struct), GFP_KERNEL);
332                 if (!new_struct) {
333                         clear_op_struct_pool();
334                         return -ENOMEM;
335                 }
336                 new_struct->next = op_struct_list;
337                 op_struct_list = new_struct;
338         }
339         return 0;
340 }
341
342 /* Allocate an op structure from our pool */
343 static struct op_struct *get_op_struct(void)
344 {
345         struct op_struct *retval;
346         unsigned long flags;
347
348         spin_lock_irqsave(&op_struct_list_lock, flags);
349         retval = op_struct_list;
350         if (retval)
351                 op_struct_list = retval->next;
352         spin_unlock_irqrestore(&op_struct_list_lock, flags);
353         if (retval) {
354                 memset(retval, 0, sizeof(*retval));
355                 init_completion(&retval->com);
356         }
357
358         return retval;
359 }
360
361 /* Return an op structure to our pool */
362 static void free_op_struct(struct op_struct *op_struct)
363 {
364         unsigned long flags;
365
366         spin_lock_irqsave(&op_struct_list_lock, flags);
367         op_struct->next = op_struct_list;
368         op_struct_list = op_struct;
369         spin_unlock_irqrestore(&op_struct_list_lock, flags);
370 }
371
372 /* Map our tape return codes to errno values */
373 int tape_rc_to_errno(int tape_rc, char *operation, int tapeno)
374 {
375         const struct vio_error_entry *err;
376
377         if (tape_rc == 0)
378                 return 0;
379
380         err = vio_lookup_rc(viotape_err_table, tape_rc);
381         printk(VIOTAPE_KERN_WARN "error(%s) 0x%04x on Device %d (%-10s): %s\n",
382                         operation, tape_rc, tapeno,
383                         viotape_unitinfo[tapeno].rsrcname, err->msg);
384         return -err->errno;
385 }
386
387 /* Get info on all tapes from OS/400 */
388 static int get_viotape_info(void)
389 {
390         HvLpEvent_Rc hvrc;
391         int i;
392         size_t len = sizeof(*viotape_unitinfo) * VIOTAPE_MAX_TAPE;
393         struct op_struct *op = get_op_struct();
394
395         if (op == NULL)
396                 return -ENOMEM;
397
398         viotape_unitinfo = dma_alloc_coherent(iSeries_vio_dev, len,
399                 &viotape_unitinfo_token, GFP_ATOMIC);
400         if (viotape_unitinfo == NULL) {
401                 free_op_struct(op);
402                 return -ENOMEM;
403         }
404
405         memset(viotape_unitinfo, 0, len);
406
407         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
408                         HvLpEvent_Type_VirtualIo,
409                         viomajorsubtype_tape | viotapegetinfo,
410                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
411                         viopath_sourceinst(viopath_hostLp),
412                         viopath_targetinst(viopath_hostLp),
413                         (u64) (unsigned long) op, VIOVERSION << 16,
414                         viotape_unitinfo_token, len, 0, 0);
415         if (hvrc != HvLpEvent_Rc_Good) {
416                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
417                                 (int)hvrc);
418                 free_op_struct(op);
419                 return -EIO;
420         }
421
422         wait_for_completion(&op->com);
423
424         free_op_struct(op);
425
426         for (i = 0;
427              ((i < VIOTAPE_MAX_TAPE) && (viotape_unitinfo[i].rsrcname[0]));
428              i++)
429                 viotape_numdev++;
430         return 0;
431 }
432
433
434 /* Write */
435 static ssize_t viotap_write(struct file *file, const char *buf,
436                 size_t count, loff_t * ppos)
437 {
438         HvLpEvent_Rc hvrc;
439         unsigned short flags = file->f_flags;
440         int noblock = ((flags & O_NONBLOCK) != 0);
441         ssize_t ret;
442         struct viot_devinfo_struct devi;
443         struct op_struct *op = get_op_struct();
444
445         if (op == NULL)
446                 return -ENOMEM;
447
448         get_dev_info(file->f_dentry->d_inode, &devi);
449
450         /*
451          * We need to make sure we can send a request.  We use
452          * a semaphore to keep track of # requests in use.  If
453          * we are non-blocking, make sure we don't block on the
454          * semaphore
455          */
456         if (noblock) {
457                 if (down_trylock(&reqSem)) {
458                         ret = -EWOULDBLOCK;
459                         goto free_op;
460                 }
461         } else
462                 down(&reqSem);
463
464         /* Allocate a DMA buffer */
465         op->dev = tape_device[devi.devno];
466         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
467                         GFP_ATOMIC);
468
469         if (op->buffer == NULL) {
470                 printk(VIOTAPE_KERN_WARN
471                                 "error allocating dma buffer for len %ld\n",
472                                 count);
473                 ret = -EFAULT;
474                 goto up_sem;
475         }
476
477         /* Copy the data into the buffer */
478         if (copy_from_user(op->buffer, buf, count)) {
479                 printk(VIOTAPE_KERN_WARN "tape: error on copy from user\n");
480                 ret = -EFAULT;
481                 goto free_dma;
482         }
483
484         op->non_blocking = noblock;
485         init_completion(&op->com);
486         op->count = count;
487
488         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
489                         HvLpEvent_Type_VirtualIo,
490                         viomajorsubtype_tape | viotapewrite,
491                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
492                         viopath_sourceinst(viopath_hostLp),
493                         viopath_targetinst(viopath_hostLp),
494                         (u64)(unsigned long)op, VIOVERSION << 16,
495                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
496         if (hvrc != HvLpEvent_Rc_Good) {
497                 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
498                                 (int)hvrc);
499                 ret = -EIO;
500                 goto free_dma;
501         }
502
503         if (noblock)
504                 return count;
505
506         wait_for_completion(&op->com);
507
508         if (op->rc)
509                 ret = tape_rc_to_errno(op->rc, "write", devi.devno);
510         else {
511                 chg_state(devi.devno, VIOT_WRITING, file);
512                 ret = op->count;
513         }
514
515 free_dma:
516         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
517 up_sem:
518         up(&reqSem);
519 free_op:
520         free_op_struct(op);
521         return ret;
522 }
523
524 /* read */
525 static ssize_t viotap_read(struct file *file, char *buf, size_t count,
526                 loff_t *ptr)
527 {
528         HvLpEvent_Rc hvrc;
529         unsigned short flags = file->f_flags;
530         struct op_struct *op = get_op_struct();
531         int noblock = ((flags & O_NONBLOCK) != 0);
532         ssize_t ret;
533         struct viot_devinfo_struct devi;
534
535         if (op == NULL)
536                 return -ENOMEM;
537
538         get_dev_info(file->f_dentry->d_inode, &devi);
539
540         /*
541          * We need to make sure we can send a request.  We use
542          * a semaphore to keep track of # requests in use.  If
543          * we are non-blocking, make sure we don't block on the
544          * semaphore
545          */
546         if (noblock) {
547                 if (down_trylock(&reqSem)) {
548                         ret = -EWOULDBLOCK;
549                         goto free_op;
550                 }
551         } else
552                 down(&reqSem);
553
554         chg_state(devi.devno, VIOT_READING, file);
555
556         /* Allocate a DMA buffer */
557         op->dev = tape_device[devi.devno];
558         op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
559                         GFP_ATOMIC);
560         if (op->buffer == NULL) {
561                 ret = -EFAULT;
562                 goto up_sem;
563         }
564
565         op->count = count;
566         init_completion(&op->com);
567
568         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
569                         HvLpEvent_Type_VirtualIo,
570                         viomajorsubtype_tape | viotaperead,
571                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
572                         viopath_sourceinst(viopath_hostLp),
573                         viopath_targetinst(viopath_hostLp),
574                         (u64)(unsigned long)op, VIOVERSION << 16,
575                         ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
576         if (hvrc != HvLpEvent_Rc_Good) {
577                 printk(VIOTAPE_KERN_WARN "tape hv error on op %d\n",
578                                 (int)hvrc);
579                 ret = -EIO;
580                 goto free_dma;
581         }
582
583         wait_for_completion(&op->com);
584
585         if (op->rc)
586                 ret = tape_rc_to_errno(op->rc, "read", devi.devno);
587         else {
588                 ret = op->count;
589                 if (ret && copy_to_user(buf, op->buffer, ret)) {
590                         printk(VIOTAPE_KERN_WARN "error on copy_to_user\n");
591                         ret = -EFAULT;
592                 }
593         }
594
595 free_dma:
596         dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
597 up_sem:
598         up(&reqSem);
599 free_op:
600         free_op_struct(op);
601         return ret;
602 }
603
604 /* ioctl */
605 static int viotap_ioctl(struct inode *inode, struct file *file,
606                 unsigned int cmd, unsigned long arg)
607 {
608         HvLpEvent_Rc hvrc;
609         int ret;
610         struct viot_devinfo_struct devi;
611         struct mtop mtc;
612         u32 myOp;
613         struct op_struct *op = get_op_struct();
614
615         if (op == NULL)
616                 return -ENOMEM;
617
618         get_dev_info(file->f_dentry->d_inode, &devi);
619
620         down(&reqSem);
621
622         ret = -EINVAL;
623
624         switch (cmd) {
625         case MTIOCTOP:
626                 ret = -EFAULT;
627                 /*
628                  * inode is null if and only if we (the kernel)
629                  * made the request
630                  */
631                 if (inode == NULL)
632                         memcpy(&mtc, (void *) arg, sizeof(struct mtop));
633                 else if (copy_from_user((char *)&mtc, (char *)arg,
634                                         sizeof(struct mtop)))
635                         goto free_op;
636
637                 ret = -EIO;
638                 switch (mtc.mt_op) {
639                 case MTRESET:
640                         myOp = VIOTAPOP_RESET;
641                         break;
642                 case MTFSF:
643                         myOp = VIOTAPOP_FSF;
644                         break;
645                 case MTBSF:
646                         myOp = VIOTAPOP_BSF;
647                         break;
648                 case MTFSR:
649                         myOp = VIOTAPOP_FSR;
650                         break;
651                 case MTBSR:
652                         myOp = VIOTAPOP_BSR;
653                         break;
654                 case MTWEOF:
655                         myOp = VIOTAPOP_WEOF;
656                         break;
657                 case MTREW:
658                         myOp = VIOTAPOP_REW;
659                         break;
660                 case MTNOP:
661                         myOp = VIOTAPOP_NOP;
662                         break;
663                 case MTEOM:
664                         myOp = VIOTAPOP_EOM;
665                         break;
666                 case MTERASE:
667                         myOp = VIOTAPOP_ERASE;
668                         break;
669                 case MTSETBLK:
670                         myOp = VIOTAPOP_SETBLK;
671                         break;
672                 case MTSETDENSITY:
673                         myOp = VIOTAPOP_SETDENSITY;
674                         break;
675                 case MTTELL:
676                         myOp = VIOTAPOP_GETPOS;
677                         break;
678                 case MTSEEK:
679                         myOp = VIOTAPOP_SETPOS;
680                         break;
681                 case MTSETPART:
682                         myOp = VIOTAPOP_SETPART;
683                         break;
684                 case MTOFFL:
685                         myOp = VIOTAPOP_UNLOAD;
686                         break;
687                 default:
688                         printk(VIOTAPE_KERN_WARN "MTIOCTOP called "
689                                         "with invalid op 0x%x\n", mtc.mt_op);
690                         goto free_op;
691                 }
692
693                 /*
694                  * if we moved the head, we are no longer
695                  * reading or writing
696                  */
697                 switch (mtc.mt_op) {
698                 case MTFSF:
699                 case MTBSF:
700                 case MTFSR:
701                 case MTBSR:
702                 case MTTELL:
703                 case MTSEEK:
704                 case MTREW:
705                         chg_state(devi.devno, VIOT_IDLE, file);
706                 }
707
708                 init_completion(&op->com);
709                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
710                                 HvLpEvent_Type_VirtualIo,
711                                 viomajorsubtype_tape | viotapeop,
712                                 HvLpEvent_AckInd_DoAck,
713                                 HvLpEvent_AckType_ImmediateAck,
714                                 viopath_sourceinst(viopath_hostLp),
715                                 viopath_targetinst(viopath_hostLp),
716                                 (u64)(unsigned long)op,
717                                 VIOVERSION << 16,
718                                 ((u64)devi.devno << 48), 0,
719                                 (((u64)myOp) << 32) | mtc.mt_count, 0);
720                 if (hvrc != HvLpEvent_Rc_Good) {
721                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
722                                         (int)hvrc);
723                         goto free_op;
724                 }
725                 wait_for_completion(&op->com);
726                 ret = tape_rc_to_errno(op->rc, "tape operation", devi.devno);
727                 goto free_op;
728
729         case MTIOCGET:
730                 ret = -EIO;
731                 init_completion(&op->com);
732                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
733                                 HvLpEvent_Type_VirtualIo,
734                                 viomajorsubtype_tape | viotapegetstatus,
735                                 HvLpEvent_AckInd_DoAck,
736                                 HvLpEvent_AckType_ImmediateAck,
737                                 viopath_sourceinst(viopath_hostLp),
738                                 viopath_targetinst(viopath_hostLp),
739                                 (u64)(unsigned long)op, VIOVERSION << 16,
740                                 ((u64)devi.devno << 48), 0, 0, 0);
741                 if (hvrc != HvLpEvent_Rc_Good) {
742                         printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
743                                         (int)hvrc);
744                         goto free_op;
745                 }
746                 wait_for_completion(&op->com);
747
748                 /* Operation is complete - grab the error code */
749                 ret = tape_rc_to_errno(op->rc, "get status", devi.devno);
750                 free_op_struct(op);
751                 up(&reqSem);
752
753                 if ((ret == 0) && copy_to_user((void *)arg,
754                                         &viomtget[devi.devno],
755                                         sizeof(viomtget[0])))
756                         ret = -EFAULT;
757                 return ret;
758         case MTIOCPOS:
759                 printk(VIOTAPE_KERN_WARN "Got an (unsupported) MTIOCPOS\n");
760                 break;
761         default:
762                 printk(VIOTAPE_KERN_WARN "got an unsupported ioctl 0x%0x\n",
763                                 cmd);
764                 break;
765         }
766
767 free_op:
768         free_op_struct(op);
769         up(&reqSem);
770         return ret;
771 }
772
773 static int viotap_open(struct inode *inode, struct file *file)
774 {
775         HvLpEvent_Rc hvrc;
776         struct viot_devinfo_struct devi;
777         int ret;
778         struct op_struct *op = get_op_struct();
779
780         if (op == NULL)
781                 return -ENOMEM;
782
783         get_dev_info(file->f_dentry->d_inode, &devi);
784
785         /* Note: We currently only support one mode! */
786         if ((devi.devno >= viotape_numdev) || (devi.mode)) {
787                 ret = -ENODEV;
788                 goto free_op;
789         }
790
791         init_completion(&op->com);
792
793         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
794                         HvLpEvent_Type_VirtualIo,
795                         viomajorsubtype_tape | viotapeopen,
796                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
797                         viopath_sourceinst(viopath_hostLp),
798                         viopath_targetinst(viopath_hostLp),
799                         (u64)(unsigned long)op, VIOVERSION << 16,
800                         ((u64)devi.devno << 48), 0, 0, 0);
801         if (hvrc != 0) {
802                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
803                                 (int) hvrc);
804                 ret = -EIO;
805                 goto free_op;
806         }
807
808         wait_for_completion(&op->com);
809         ret = tape_rc_to_errno(op->rc, "open", devi.devno);
810
811 free_op:
812         free_op_struct(op);
813         return ret;
814 }
815
816
817 static int viotap_release(struct inode *inode, struct file *file)
818 {
819         HvLpEvent_Rc hvrc;
820         struct viot_devinfo_struct devi;
821         int ret = 0;
822         struct op_struct *op = get_op_struct();
823
824         if (op == NULL)
825                 return -ENOMEM;
826         init_completion(&op->com);
827
828         get_dev_info(file->f_dentry->d_inode, &devi);
829
830         if (devi.devno >= viotape_numdev) {
831                 ret = -ENODEV;
832                 goto free_op;
833         }
834
835         chg_state(devi.devno, VIOT_IDLE, file);
836
837         if (devi.rewind) {
838                 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
839                                 HvLpEvent_Type_VirtualIo,
840                                 viomajorsubtype_tape | viotapeop,
841                                 HvLpEvent_AckInd_DoAck,
842                                 HvLpEvent_AckType_ImmediateAck,
843                                 viopath_sourceinst(viopath_hostLp),
844                                 viopath_targetinst(viopath_hostLp),
845                                 (u64)(unsigned long)op, VIOVERSION << 16,
846                                 ((u64)devi.devno << 48), 0,
847                                 ((u64)VIOTAPOP_REW) << 32, 0);
848                 wait_for_completion(&op->com);
849
850                 tape_rc_to_errno(op->rc, "rewind", devi.devno);
851         }
852
853         hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
854                         HvLpEvent_Type_VirtualIo,
855                         viomajorsubtype_tape | viotapeclose,
856                         HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
857                         viopath_sourceinst(viopath_hostLp),
858                         viopath_targetinst(viopath_hostLp),
859                         (u64)(unsigned long)op, VIOVERSION << 16,
860                         ((u64)devi.devno << 48), 0, 0, 0);
861         if (hvrc != 0) {
862                 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
863                                 (int) hvrc);
864                 ret = -EIO;
865                 goto free_op;
866         }
867
868         wait_for_completion(&op->com);
869
870         if (op->rc)
871                 printk(VIOTAPE_KERN_WARN "close failed\n");
872
873 free_op:
874         free_op_struct(op);
875         return ret;
876 }
877
878 struct file_operations viotap_fops = {
879         owner: THIS_MODULE,
880         read: viotap_read,
881         write: viotap_write,
882         ioctl: viotap_ioctl,
883         open: viotap_open,
884         release: viotap_release,
885 };
886
887 /* Handle interrupt events for tape */
888 static void vioHandleTapeEvent(struct HvLpEvent *event)
889 {
890         int tapeminor;
891         struct op_struct *op;
892         struct viotapelpevent *tevent = (struct viotapelpevent *)event;
893
894         if (event == NULL) {
895                 /* Notification that a partition went away! */
896                 if (!viopath_isactive(viopath_hostLp)) {
897                         /* TODO! Clean up */
898                 }
899                 return;
900         }
901
902         tapeminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
903         op = (struct op_struct *)event->xCorrelationToken;
904         switch (tapeminor) {
905         case viotapegetinfo:
906         case viotapeopen:
907         case viotapeclose:
908                 op->rc = tevent->sub_type_result;
909                 complete(&op->com);
910                 break;
911         case viotaperead:
912                 op->rc = tevent->sub_type_result;
913                 op->count = tevent->len;
914                 complete(&op->com);
915                 break;
916         case viotapewrite:
917                 if (op->non_blocking) {
918                         dma_free_coherent(op->dev, op->count,
919                                         op->buffer, op->dmaaddr);
920                         free_op_struct(op);
921                         up(&reqSem);
922                 } else {
923                         op->rc = tevent->sub_type_result;
924                         op->count = tevent->len;
925                         complete(&op->com);
926                 }
927                 break;
928         case viotapeop:
929         case viotapegetpos:
930         case viotapesetpos:
931         case viotapegetstatus:
932                 if (op) {
933                         op->count = tevent->u.op.count;
934                         op->rc = tevent->sub_type_result;
935                         if (!op->non_blocking)
936                                 complete(&op->com);
937                 }
938                 break;
939         default:
940                 printk(VIOTAPE_KERN_WARN "weird ack\n");
941         }
942 }
943
944 static int viotape_probe(struct vio_dev *vdev, const struct vio_device_id *id)
945 {
946         char tapename[32];
947         int i = vdev->unit_address;
948         int j;
949
950         if (i >= viotape_numdev)
951                 return -ENODEV;
952
953         tape_device[i] = &vdev->dev;
954
955         state[i].cur_part = 0;
956         for (j = 0; j < MAX_PARTITIONS; ++j)
957                 state[i].part_stat_rwi[j] = VIOT_IDLE;
958         class_device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i), NULL,
959                         "iseries!vt%d", i);
960         class_device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i | 0x80),
961                         NULL, "iseries!nvt%d", i);
962         devfs_mk_cdev(MKDEV(VIOTAPE_MAJOR, i), S_IFCHR | S_IRUSR | S_IWUSR,
963                         "iseries/vt%d", i);
964         devfs_mk_cdev(MKDEV(VIOTAPE_MAJOR, i | 0x80),
965                         S_IFCHR | S_IRUSR | S_IWUSR, "iseries/nvt%d", i);
966         sprintf(tapename, "iseries/vt%d", i);
967         state[i].dev_handle = devfs_register_tape(tapename);
968         printk(VIOTAPE_KERN_INFO "tape %s is iSeries "
969                         "resource %10.10s type %4.4s, model %3.3s\n",
970                         tapename, viotape_unitinfo[i].rsrcname,
971                         viotape_unitinfo[i].type, viotape_unitinfo[i].model);
972         return 0;
973 }
974
975 static int viotape_remove(struct vio_dev *vdev)
976 {
977         int i = vdev->unit_address;
978
979         devfs_remove("iseries/nvt%d", i);
980         devfs_remove("iseries/vt%d", i);
981         devfs_unregister_tape(state[i].dev_handle);
982         class_device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i | 0x80));
983         class_device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i));
984         return 0;
985 }
986
987 /**
988  * viotape_device_table: Used by vio.c to match devices that we
989  * support.
990  */
991 static struct vio_device_id viotape_device_table[] __devinitdata = {
992         { "byte", "IBM,iSeries-viotape" },
993         { "", "" }
994 };
995 MODULE_DEVICE_TABLE(vio, viotape_device_table);
996
997 static struct vio_driver viotape_driver = {
998         .id_table = viotape_device_table,
999         .probe = viotape_probe,
1000         .remove = viotape_remove,
1001         .driver = {
1002                 .name = "viotape",
1003                 .owner = THIS_MODULE,
1004         }
1005 };
1006
1007
1008 int __init viotap_init(void)
1009 {
1010         int ret;
1011         struct proc_dir_entry *e;
1012
1013         op_struct_list = NULL;
1014         if ((ret = add_op_structs(VIOTAPE_MAXREQ)) < 0) {
1015                 printk(VIOTAPE_KERN_WARN "couldn't allocate op structs\n");
1016                 return ret;
1017         }
1018         spin_lock_init(&op_struct_list_lock);
1019
1020         sema_init(&reqSem, VIOTAPE_MAXREQ);
1021
1022         if (viopath_hostLp == HvLpIndexInvalid) {
1023                 vio_set_hostlp();
1024                 if (viopath_hostLp == HvLpIndexInvalid) {
1025                         ret = -ENODEV;
1026                         goto clear_op;
1027                 }
1028         }
1029
1030         ret = viopath_open(viopath_hostLp, viomajorsubtype_tape,
1031                         VIOTAPE_MAXREQ + 2);
1032         if (ret) {
1033                 printk(VIOTAPE_KERN_WARN
1034                                 "error on viopath_open to hostlp %d\n", ret);
1035                 ret = -EIO;
1036                 goto clear_op;
1037         }
1038
1039         printk(VIOTAPE_KERN_INFO "vers " VIOTAPE_VERSION
1040                         ", hosting partition %d\n", viopath_hostLp);
1041
1042         vio_setHandler(viomajorsubtype_tape, vioHandleTapeEvent);
1043
1044         ret = register_chrdev(VIOTAPE_MAJOR, "viotape", &viotap_fops);
1045         if (ret < 0) {
1046                 printk(VIOTAPE_KERN_WARN "Error registering viotape device\n");
1047                 goto clear_handler;
1048         }
1049
1050         tape_class = class_create(THIS_MODULE, "tape");
1051         if (IS_ERR(tape_class)) {
1052                 printk(VIOTAPE_KERN_WARN "Unable to allocat class\n");
1053                 ret = PTR_ERR(tape_class);
1054                 goto unreg_chrdev;
1055         }
1056
1057         if ((ret = get_viotape_info()) < 0) {
1058                 printk(VIOTAPE_KERN_WARN "Unable to obtain virtual device information");
1059                 goto unreg_class;
1060         }
1061
1062         ret = vio_register_driver(&viotape_driver);
1063         if (ret)
1064                 goto unreg_class;
1065
1066         e = create_proc_entry("iSeries/viotape", S_IFREG|S_IRUGO, NULL);
1067         if (e) {
1068                 e->owner = THIS_MODULE;
1069                 e->proc_fops = &proc_viotape_operations;
1070         }
1071
1072         return 0;
1073
1074 unreg_class:
1075         class_destroy(tape_class);
1076 unreg_chrdev:
1077         unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1078 clear_handler:
1079         vio_clearHandler(viomajorsubtype_tape);
1080         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1081 clear_op:
1082         clear_op_struct_pool();
1083         return ret;
1084 }
1085
1086 /* Give a new state to the tape object */
1087 static int chg_state(int index, unsigned char new_state, struct file *file)
1088 {
1089         unsigned char *cur_state =
1090             &state[index].part_stat_rwi[state[index].cur_part];
1091         int rc = 0;
1092
1093         /* if the same state, don't bother */
1094         if (*cur_state == new_state)
1095                 return 0;
1096
1097         /* write an EOF if changing from writing to some other state */
1098         if (*cur_state == VIOT_WRITING) {
1099                 struct mtop write_eof = { MTWEOF, 1 };
1100
1101                 rc = viotap_ioctl(NULL, file, MTIOCTOP,
1102                                   (unsigned long)&write_eof);
1103         }
1104         *cur_state = new_state;
1105         return rc;
1106 }
1107
1108 /* Cleanup */
1109 static void __exit viotap_exit(void)
1110 {
1111         int ret;
1112
1113         remove_proc_entry("iSeries/viotape", NULL);
1114         vio_unregister_driver(&viotape_driver);
1115         class_destroy(tape_class);
1116         ret = unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1117         if (ret < 0)
1118                 printk(VIOTAPE_KERN_WARN "Error unregistering device: %d\n",
1119                                 ret);
1120         if (viotape_unitinfo)
1121                 dma_free_coherent(iSeries_vio_dev,
1122                                 sizeof(viotape_unitinfo[0]) * VIOTAPE_MAX_TAPE,
1123                                 viotape_unitinfo, viotape_unitinfo_token);
1124         viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1125         vio_clearHandler(viomajorsubtype_tape);
1126         clear_op_struct_pool();
1127 }
1128
1129 MODULE_LICENSE("GPL");
1130 module_init(viotap_init);
1131 module_exit(viotap_exit);