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