Btrfs: check for a null fs root when writing to the backup root log
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / char / viotape.c
blobad6e64a2912d6fe61d06d7c20135e76a92bc9e1c
1 /* -*- linux-c -*-
2 * drivers/char/viotape.c
4 * iSeries Virtual Tape
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
11 * (C) Copyright 2000-2004 IBM Corporation
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.
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.
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
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.
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
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/mutex.h>
50 #include <linux/slab.h>
52 #include <asm/uaccess.h>
53 #include <asm/ioctls.h>
54 #include <asm/firmware.h>
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>
61 #define VIOTAPE_VERSION "1.2"
62 #define VIOTAPE_MAXREQ 1
64 #define VIOTAPE_KERN_WARN KERN_WARNING "viotape: "
65 #define VIOTAPE_KERN_INFO KERN_INFO "viotape: "
67 static DEFINE_MUTEX(proc_viotape_mutex);
68 static int viotape_numdev;
71 * The minor number follows the conventions of the SCSI tape drives. The
72 * rewind and mode are encoded in the minor #. We use this struct to break
73 * them out
75 struct viot_devinfo_struct {
76 int devno;
77 int mode;
78 int rewind;
81 #define VIOTAPOP_RESET 0
82 #define VIOTAPOP_FSF 1
83 #define VIOTAPOP_BSF 2
84 #define VIOTAPOP_FSR 3
85 #define VIOTAPOP_BSR 4
86 #define VIOTAPOP_WEOF 5
87 #define VIOTAPOP_REW 6
88 #define VIOTAPOP_NOP 7
89 #define VIOTAPOP_EOM 8
90 #define VIOTAPOP_ERASE 9
91 #define VIOTAPOP_SETBLK 10
92 #define VIOTAPOP_SETDENSITY 11
93 #define VIOTAPOP_SETPOS 12
94 #define VIOTAPOP_GETPOS 13
95 #define VIOTAPOP_SETPART 14
96 #define VIOTAPOP_UNLOAD 15
98 enum viotaperc {
99 viotape_InvalidRange = 0x0601,
100 viotape_InvalidToken = 0x0602,
101 viotape_DMAError = 0x0603,
102 viotape_UseError = 0x0604,
103 viotape_ReleaseError = 0x0605,
104 viotape_InvalidTape = 0x0606,
105 viotape_InvalidOp = 0x0607,
106 viotape_TapeErr = 0x0608,
108 viotape_AllocTimedOut = 0x0640,
109 viotape_BOTEnc = 0x0641,
110 viotape_BlankTape = 0x0642,
111 viotape_BufferEmpty = 0x0643,
112 viotape_CleanCartFound = 0x0644,
113 viotape_CmdNotAllowed = 0x0645,
114 viotape_CmdNotSupported = 0x0646,
115 viotape_DataCheck = 0x0647,
116 viotape_DecompressErr = 0x0648,
117 viotape_DeviceTimeout = 0x0649,
118 viotape_DeviceUnavail = 0x064a,
119 viotape_DeviceBusy = 0x064b,
120 viotape_EndOfMedia = 0x064c,
121 viotape_EndOfTape = 0x064d,
122 viotape_EquipCheck = 0x064e,
123 viotape_InsufficientRs = 0x064f,
124 viotape_InvalidLogBlk = 0x0650,
125 viotape_LengthError = 0x0651,
126 viotape_LibDoorOpen = 0x0652,
127 viotape_LoadFailure = 0x0653,
128 viotape_NotCapable = 0x0654,
129 viotape_NotOperational = 0x0655,
130 viotape_NotReady = 0x0656,
131 viotape_OpCancelled = 0x0657,
132 viotape_PhyLinkErr = 0x0658,
133 viotape_RdyNotBOT = 0x0659,
134 viotape_TapeMark = 0x065a,
135 viotape_WriteProt = 0x065b
138 static const struct vio_error_entry viotape_err_table[] = {
139 { viotape_InvalidRange, EIO, "Internal error" },
140 { viotape_InvalidToken, EIO, "Internal error" },
141 { viotape_DMAError, EIO, "DMA error" },
142 { viotape_UseError, EIO, "Internal error" },
143 { viotape_ReleaseError, EIO, "Internal error" },
144 { viotape_InvalidTape, EIO, "Invalid tape device" },
145 { viotape_InvalidOp, EIO, "Invalid operation" },
146 { viotape_TapeErr, EIO, "Tape error" },
147 { viotape_AllocTimedOut, EBUSY, "Allocate timed out" },
148 { viotape_BOTEnc, EIO, "Beginning of tape encountered" },
149 { viotape_BlankTape, EIO, "Blank tape" },
150 { viotape_BufferEmpty, EIO, "Buffer empty" },
151 { viotape_CleanCartFound, ENOMEDIUM, "Cleaning cartridge found" },
152 { viotape_CmdNotAllowed, EIO, "Command not allowed" },
153 { viotape_CmdNotSupported, EIO, "Command not supported" },
154 { viotape_DataCheck, EIO, "Data check" },
155 { viotape_DecompressErr, EIO, "Decompression error" },
156 { viotape_DeviceTimeout, EBUSY, "Device timeout" },
157 { viotape_DeviceUnavail, EIO, "Device unavailable" },
158 { viotape_DeviceBusy, EBUSY, "Device busy" },
159 { viotape_EndOfMedia, ENOSPC, "End of media" },
160 { viotape_EndOfTape, ENOSPC, "End of tape" },
161 { viotape_EquipCheck, EIO, "Equipment check" },
162 { viotape_InsufficientRs, EOVERFLOW, "Insufficient tape resources" },
163 { viotape_InvalidLogBlk, EIO, "Invalid logical block location" },
164 { viotape_LengthError, EOVERFLOW, "Length error" },
165 { viotape_LibDoorOpen, EBUSY, "Door open" },
166 { viotape_LoadFailure, ENOMEDIUM, "Load failure" },
167 { viotape_NotCapable, EIO, "Not capable" },
168 { viotape_NotOperational, EIO, "Not operational" },
169 { viotape_NotReady, EIO, "Not ready" },
170 { viotape_OpCancelled, EIO, "Operation cancelled" },
171 { viotape_PhyLinkErr, EIO, "Physical link error" },
172 { viotape_RdyNotBOT, EIO, "Ready but not beginning of tape" },
173 { viotape_TapeMark, EIO, "Tape mark" },
174 { viotape_WriteProt, EROFS, "Write protection error" },
175 { 0, 0, NULL },
178 /* Maximum number of tapes we support */
179 #define VIOTAPE_MAX_TAPE HVMAXARCHITECTEDVIRTUALTAPES
180 #define MAX_PARTITIONS 4
182 /* defines for current tape state */
183 #define VIOT_IDLE 0
184 #define VIOT_READING 1
185 #define VIOT_WRITING 2
187 /* Our info on the tapes */
188 static struct {
189 const char *rsrcname;
190 const char *type;
191 const char *model;
192 } viotape_unitinfo[VIOTAPE_MAX_TAPE];
194 static struct mtget viomtget[VIOTAPE_MAX_TAPE];
196 static struct class *tape_class;
198 static struct device *tape_device[VIOTAPE_MAX_TAPE];
201 * maintain the current state of each tape (and partition)
202 * so that we know when to write EOF marks.
204 static struct {
205 unsigned char cur_part;
206 unsigned char part_stat_rwi[MAX_PARTITIONS];
207 } state[VIOTAPE_MAX_TAPE];
209 /* We single-thread */
210 static struct semaphore reqSem;
213 * When we send a request, we use this struct to get the response back
214 * from the interrupt handler
216 struct op_struct {
217 void *buffer;
218 dma_addr_t dmaaddr;
219 size_t count;
220 int rc;
221 int non_blocking;
222 struct completion com;
223 struct device *dev;
224 struct op_struct *next;
227 static spinlock_t op_struct_list_lock;
228 static struct op_struct *op_struct_list;
230 /* forward declaration to resolve interdependence */
231 static int chg_state(int index, unsigned char new_state, struct file *file);
233 /* procfs support */
234 static int proc_viotape_show(struct seq_file *m, void *v)
236 int i;
238 seq_printf(m, "viotape driver version " VIOTAPE_VERSION "\n");
239 for (i = 0; i < viotape_numdev; i++) {
240 seq_printf(m, "viotape device %d is iSeries resource %10.10s"
241 "type %4.4s, model %3.3s\n",
242 i, viotape_unitinfo[i].rsrcname,
243 viotape_unitinfo[i].type,
244 viotape_unitinfo[i].model);
246 return 0;
249 static int proc_viotape_open(struct inode *inode, struct file *file)
251 return single_open(file, proc_viotape_show, NULL);
254 static const struct file_operations proc_viotape_operations = {
255 .owner = THIS_MODULE,
256 .open = proc_viotape_open,
257 .read = seq_read,
258 .llseek = seq_lseek,
259 .release = single_release,
262 /* Decode the device minor number into its parts */
263 void get_dev_info(struct inode *ino, struct viot_devinfo_struct *devi)
265 devi->devno = iminor(ino) & 0x1F;
266 devi->mode = (iminor(ino) & 0x60) >> 5;
267 /* if bit is set in the minor, do _not_ rewind automatically */
268 devi->rewind = (iminor(ino) & 0x80) == 0;
271 /* This is called only from the exit and init paths, so no need for locking */
272 static void clear_op_struct_pool(void)
274 while (op_struct_list) {
275 struct op_struct *toFree = op_struct_list;
276 op_struct_list = op_struct_list->next;
277 kfree(toFree);
281 /* Likewise, this is only called from the init path */
282 static int add_op_structs(int structs)
284 int i;
286 for (i = 0; i < structs; ++i) {
287 struct op_struct *new_struct =
288 kmalloc(sizeof(*new_struct), GFP_KERNEL);
289 if (!new_struct) {
290 clear_op_struct_pool();
291 return -ENOMEM;
293 new_struct->next = op_struct_list;
294 op_struct_list = new_struct;
296 return 0;
299 /* Allocate an op structure from our pool */
300 static struct op_struct *get_op_struct(void)
302 struct op_struct *retval;
303 unsigned long flags;
305 spin_lock_irqsave(&op_struct_list_lock, flags);
306 retval = op_struct_list;
307 if (retval)
308 op_struct_list = retval->next;
309 spin_unlock_irqrestore(&op_struct_list_lock, flags);
310 if (retval) {
311 memset(retval, 0, sizeof(*retval));
312 init_completion(&retval->com);
315 return retval;
318 /* Return an op structure to our pool */
319 static void free_op_struct(struct op_struct *op_struct)
321 unsigned long flags;
323 spin_lock_irqsave(&op_struct_list_lock, flags);
324 op_struct->next = op_struct_list;
325 op_struct_list = op_struct;
326 spin_unlock_irqrestore(&op_struct_list_lock, flags);
329 /* Map our tape return codes to errno values */
330 int tape_rc_to_errno(int tape_rc, char *operation, int tapeno)
332 const struct vio_error_entry *err;
334 if (tape_rc == 0)
335 return 0;
337 err = vio_lookup_rc(viotape_err_table, tape_rc);
338 printk(VIOTAPE_KERN_WARN "error(%s) 0x%04x on Device %d (%-10s): %s\n",
339 operation, tape_rc, tapeno,
340 viotape_unitinfo[tapeno].rsrcname, err->msg);
341 return -err->errno;
344 /* Write */
345 static ssize_t viotap_write(struct file *file, const char *buf,
346 size_t count, loff_t * ppos)
348 HvLpEvent_Rc hvrc;
349 unsigned short flags = file->f_flags;
350 int noblock = ((flags & O_NONBLOCK) != 0);
351 ssize_t ret;
352 struct viot_devinfo_struct devi;
353 struct op_struct *op = get_op_struct();
355 if (op == NULL)
356 return -ENOMEM;
358 get_dev_info(file->f_path.dentry->d_inode, &devi);
361 * We need to make sure we can send a request. We use
362 * a semaphore to keep track of # requests in use. If
363 * we are non-blocking, make sure we don't block on the
364 * semaphore
366 if (noblock) {
367 if (down_trylock(&reqSem)) {
368 ret = -EWOULDBLOCK;
369 goto free_op;
371 } else
372 down(&reqSem);
374 /* Allocate a DMA buffer */
375 op->dev = tape_device[devi.devno];
376 op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
377 GFP_ATOMIC);
379 if (op->buffer == NULL) {
380 printk(VIOTAPE_KERN_WARN
381 "error allocating dma buffer for len %ld\n",
382 count);
383 ret = -EFAULT;
384 goto up_sem;
387 /* Copy the data into the buffer */
388 if (copy_from_user(op->buffer, buf, count)) {
389 printk(VIOTAPE_KERN_WARN "tape: error on copy from user\n");
390 ret = -EFAULT;
391 goto free_dma;
394 op->non_blocking = noblock;
395 init_completion(&op->com);
396 op->count = count;
398 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
399 HvLpEvent_Type_VirtualIo,
400 viomajorsubtype_tape | viotapewrite,
401 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
402 viopath_sourceinst(viopath_hostLp),
403 viopath_targetinst(viopath_hostLp),
404 (u64)(unsigned long)op, VIOVERSION << 16,
405 ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
406 if (hvrc != HvLpEvent_Rc_Good) {
407 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
408 (int)hvrc);
409 ret = -EIO;
410 goto free_dma;
413 if (noblock)
414 return count;
416 wait_for_completion(&op->com);
418 if (op->rc)
419 ret = tape_rc_to_errno(op->rc, "write", devi.devno);
420 else {
421 chg_state(devi.devno, VIOT_WRITING, file);
422 ret = op->count;
425 free_dma:
426 dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
427 up_sem:
428 up(&reqSem);
429 free_op:
430 free_op_struct(op);
431 return ret;
434 /* read */
435 static ssize_t viotap_read(struct file *file, char *buf, size_t count,
436 loff_t *ptr)
438 HvLpEvent_Rc hvrc;
439 unsigned short flags = file->f_flags;
440 struct op_struct *op = get_op_struct();
441 int noblock = ((flags & O_NONBLOCK) != 0);
442 ssize_t ret;
443 struct viot_devinfo_struct devi;
445 if (op == NULL)
446 return -ENOMEM;
448 get_dev_info(file->f_path.dentry->d_inode, &devi);
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
456 if (noblock) {
457 if (down_trylock(&reqSem)) {
458 ret = -EWOULDBLOCK;
459 goto free_op;
461 } else
462 down(&reqSem);
464 chg_state(devi.devno, VIOT_READING, file);
466 /* Allocate a DMA buffer */
467 op->dev = tape_device[devi.devno];
468 op->buffer = dma_alloc_coherent(op->dev, count, &op->dmaaddr,
469 GFP_ATOMIC);
470 if (op->buffer == NULL) {
471 ret = -EFAULT;
472 goto up_sem;
475 op->count = count;
476 init_completion(&op->com);
478 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
479 HvLpEvent_Type_VirtualIo,
480 viomajorsubtype_tape | viotaperead,
481 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
482 viopath_sourceinst(viopath_hostLp),
483 viopath_targetinst(viopath_hostLp),
484 (u64)(unsigned long)op, VIOVERSION << 16,
485 ((u64)devi.devno << 48) | op->dmaaddr, count, 0, 0);
486 if (hvrc != HvLpEvent_Rc_Good) {
487 printk(VIOTAPE_KERN_WARN "tape hv error on op %d\n",
488 (int)hvrc);
489 ret = -EIO;
490 goto free_dma;
493 wait_for_completion(&op->com);
495 if (op->rc)
496 ret = tape_rc_to_errno(op->rc, "read", devi.devno);
497 else {
498 ret = op->count;
499 if (ret && copy_to_user(buf, op->buffer, ret)) {
500 printk(VIOTAPE_KERN_WARN "error on copy_to_user\n");
501 ret = -EFAULT;
505 free_dma:
506 dma_free_coherent(op->dev, count, op->buffer, op->dmaaddr);
507 up_sem:
508 up(&reqSem);
509 free_op:
510 free_op_struct(op);
511 return ret;
514 /* ioctl */
515 static int viotap_ioctl(struct inode *inode, struct file *file,
516 unsigned int cmd, unsigned long arg)
518 HvLpEvent_Rc hvrc;
519 int ret;
520 struct viot_devinfo_struct devi;
521 struct mtop mtc;
522 u32 myOp;
523 struct op_struct *op = get_op_struct();
525 if (op == NULL)
526 return -ENOMEM;
528 get_dev_info(file->f_path.dentry->d_inode, &devi);
530 down(&reqSem);
532 ret = -EINVAL;
534 switch (cmd) {
535 case MTIOCTOP:
536 ret = -EFAULT;
538 * inode is null if and only if we (the kernel)
539 * made the request
541 if (inode == NULL)
542 memcpy(&mtc, (void *) arg, sizeof(struct mtop));
543 else if (copy_from_user((char *)&mtc, (char *)arg,
544 sizeof(struct mtop)))
545 goto free_op;
547 ret = -EIO;
548 switch (mtc.mt_op) {
549 case MTRESET:
550 myOp = VIOTAPOP_RESET;
551 break;
552 case MTFSF:
553 myOp = VIOTAPOP_FSF;
554 break;
555 case MTBSF:
556 myOp = VIOTAPOP_BSF;
557 break;
558 case MTFSR:
559 myOp = VIOTAPOP_FSR;
560 break;
561 case MTBSR:
562 myOp = VIOTAPOP_BSR;
563 break;
564 case MTWEOF:
565 myOp = VIOTAPOP_WEOF;
566 break;
567 case MTREW:
568 myOp = VIOTAPOP_REW;
569 break;
570 case MTNOP:
571 myOp = VIOTAPOP_NOP;
572 break;
573 case MTEOM:
574 myOp = VIOTAPOP_EOM;
575 break;
576 case MTERASE:
577 myOp = VIOTAPOP_ERASE;
578 break;
579 case MTSETBLK:
580 myOp = VIOTAPOP_SETBLK;
581 break;
582 case MTSETDENSITY:
583 myOp = VIOTAPOP_SETDENSITY;
584 break;
585 case MTTELL:
586 myOp = VIOTAPOP_GETPOS;
587 break;
588 case MTSEEK:
589 myOp = VIOTAPOP_SETPOS;
590 break;
591 case MTSETPART:
592 myOp = VIOTAPOP_SETPART;
593 break;
594 case MTOFFL:
595 myOp = VIOTAPOP_UNLOAD;
596 break;
597 default:
598 printk(VIOTAPE_KERN_WARN "MTIOCTOP called "
599 "with invalid op 0x%x\n", mtc.mt_op);
600 goto free_op;
604 * if we moved the head, we are no longer
605 * reading or writing
607 switch (mtc.mt_op) {
608 case MTFSF:
609 case MTBSF:
610 case MTFSR:
611 case MTBSR:
612 case MTTELL:
613 case MTSEEK:
614 case MTREW:
615 chg_state(devi.devno, VIOT_IDLE, file);
618 init_completion(&op->com);
619 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
620 HvLpEvent_Type_VirtualIo,
621 viomajorsubtype_tape | viotapeop,
622 HvLpEvent_AckInd_DoAck,
623 HvLpEvent_AckType_ImmediateAck,
624 viopath_sourceinst(viopath_hostLp),
625 viopath_targetinst(viopath_hostLp),
626 (u64)(unsigned long)op,
627 VIOVERSION << 16,
628 ((u64)devi.devno << 48), 0,
629 (((u64)myOp) << 32) | mtc.mt_count, 0);
630 if (hvrc != HvLpEvent_Rc_Good) {
631 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
632 (int)hvrc);
633 goto free_op;
635 wait_for_completion(&op->com);
636 ret = tape_rc_to_errno(op->rc, "tape operation", devi.devno);
637 goto free_op;
639 case MTIOCGET:
640 ret = -EIO;
641 init_completion(&op->com);
642 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
643 HvLpEvent_Type_VirtualIo,
644 viomajorsubtype_tape | viotapegetstatus,
645 HvLpEvent_AckInd_DoAck,
646 HvLpEvent_AckType_ImmediateAck,
647 viopath_sourceinst(viopath_hostLp),
648 viopath_targetinst(viopath_hostLp),
649 (u64)(unsigned long)op, VIOVERSION << 16,
650 ((u64)devi.devno << 48), 0, 0, 0);
651 if (hvrc != HvLpEvent_Rc_Good) {
652 printk(VIOTAPE_KERN_WARN "hv error on op %d\n",
653 (int)hvrc);
654 goto free_op;
656 wait_for_completion(&op->com);
658 /* Operation is complete - grab the error code */
659 ret = tape_rc_to_errno(op->rc, "get status", devi.devno);
660 free_op_struct(op);
661 up(&reqSem);
663 if ((ret == 0) && copy_to_user((void *)arg,
664 &viomtget[devi.devno],
665 sizeof(viomtget[0])))
666 ret = -EFAULT;
667 return ret;
668 case MTIOCPOS:
669 printk(VIOTAPE_KERN_WARN "Got an (unsupported) MTIOCPOS\n");
670 break;
671 default:
672 printk(VIOTAPE_KERN_WARN "got an unsupported ioctl 0x%0x\n",
673 cmd);
674 break;
677 free_op:
678 free_op_struct(op);
679 up(&reqSem);
680 return ret;
683 static long viotap_unlocked_ioctl(struct file *file,
684 unsigned int cmd, unsigned long arg)
686 long rc;
688 mutex_lock(&proc_viotape_mutex);
689 rc = viotap_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
690 mutex_unlock(&proc_viotape_mutex);
691 return rc;
694 static int viotap_open(struct inode *inode, struct file *file)
696 HvLpEvent_Rc hvrc;
697 struct viot_devinfo_struct devi;
698 int ret;
699 struct op_struct *op = get_op_struct();
701 if (op == NULL)
702 return -ENOMEM;
704 mutex_lock(&proc_viotape_mutex);
705 get_dev_info(file->f_path.dentry->d_inode, &devi);
707 /* Note: We currently only support one mode! */
708 if ((devi.devno >= viotape_numdev) || (devi.mode)) {
709 ret = -ENODEV;
710 goto free_op;
713 init_completion(&op->com);
715 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
716 HvLpEvent_Type_VirtualIo,
717 viomajorsubtype_tape | viotapeopen,
718 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
719 viopath_sourceinst(viopath_hostLp),
720 viopath_targetinst(viopath_hostLp),
721 (u64)(unsigned long)op, VIOVERSION << 16,
722 ((u64)devi.devno << 48), 0, 0, 0);
723 if (hvrc != 0) {
724 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
725 (int) hvrc);
726 ret = -EIO;
727 goto free_op;
730 wait_for_completion(&op->com);
731 ret = tape_rc_to_errno(op->rc, "open", devi.devno);
733 free_op:
734 free_op_struct(op);
735 mutex_unlock(&proc_viotape_mutex);
736 return ret;
740 static int viotap_release(struct inode *inode, struct file *file)
742 HvLpEvent_Rc hvrc;
743 struct viot_devinfo_struct devi;
744 int ret = 0;
745 struct op_struct *op = get_op_struct();
747 if (op == NULL)
748 return -ENOMEM;
749 init_completion(&op->com);
751 get_dev_info(file->f_path.dentry->d_inode, &devi);
753 if (devi.devno >= viotape_numdev) {
754 ret = -ENODEV;
755 goto free_op;
758 chg_state(devi.devno, VIOT_IDLE, file);
760 if (devi.rewind) {
761 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
762 HvLpEvent_Type_VirtualIo,
763 viomajorsubtype_tape | viotapeop,
764 HvLpEvent_AckInd_DoAck,
765 HvLpEvent_AckType_ImmediateAck,
766 viopath_sourceinst(viopath_hostLp),
767 viopath_targetinst(viopath_hostLp),
768 (u64)(unsigned long)op, VIOVERSION << 16,
769 ((u64)devi.devno << 48), 0,
770 ((u64)VIOTAPOP_REW) << 32, 0);
771 wait_for_completion(&op->com);
773 tape_rc_to_errno(op->rc, "rewind", devi.devno);
776 hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
777 HvLpEvent_Type_VirtualIo,
778 viomajorsubtype_tape | viotapeclose,
779 HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
780 viopath_sourceinst(viopath_hostLp),
781 viopath_targetinst(viopath_hostLp),
782 (u64)(unsigned long)op, VIOVERSION << 16,
783 ((u64)devi.devno << 48), 0, 0, 0);
784 if (hvrc != 0) {
785 printk(VIOTAPE_KERN_WARN "bad rc on signalLpEvent %d\n",
786 (int) hvrc);
787 ret = -EIO;
788 goto free_op;
791 wait_for_completion(&op->com);
793 if (op->rc)
794 printk(VIOTAPE_KERN_WARN "close failed\n");
796 free_op:
797 free_op_struct(op);
798 return ret;
801 const struct file_operations viotap_fops = {
802 .owner = THIS_MODULE,
803 .read = viotap_read,
804 .write = viotap_write,
805 .unlocked_ioctl = viotap_unlocked_ioctl,
806 .open = viotap_open,
807 .release = viotap_release,
808 .llseek = noop_llseek,
811 /* Handle interrupt events for tape */
812 static void vioHandleTapeEvent(struct HvLpEvent *event)
814 int tapeminor;
815 struct op_struct *op;
816 struct viotapelpevent *tevent = (struct viotapelpevent *)event;
818 if (event == NULL) {
819 /* Notification that a partition went away! */
820 if (!viopath_isactive(viopath_hostLp)) {
821 /* TODO! Clean up */
823 return;
826 tapeminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
827 op = (struct op_struct *)event->xCorrelationToken;
828 switch (tapeminor) {
829 case viotapeopen:
830 case viotapeclose:
831 op->rc = tevent->sub_type_result;
832 complete(&op->com);
833 break;
834 case viotaperead:
835 op->rc = tevent->sub_type_result;
836 op->count = tevent->len;
837 complete(&op->com);
838 break;
839 case viotapewrite:
840 if (op->non_blocking) {
841 dma_free_coherent(op->dev, op->count,
842 op->buffer, op->dmaaddr);
843 free_op_struct(op);
844 up(&reqSem);
845 } else {
846 op->rc = tevent->sub_type_result;
847 op->count = tevent->len;
848 complete(&op->com);
850 break;
851 case viotapeop:
852 case viotapegetpos:
853 case viotapesetpos:
854 case viotapegetstatus:
855 if (op) {
856 op->count = tevent->u.op.count;
857 op->rc = tevent->sub_type_result;
858 if (!op->non_blocking)
859 complete(&op->com);
861 break;
862 default:
863 printk(VIOTAPE_KERN_WARN "weird ack\n");
867 static int viotape_probe(struct vio_dev *vdev, const struct vio_device_id *id)
869 int i = vdev->unit_address;
870 int j;
871 struct device_node *node = vdev->dev.of_node;
873 if (i >= VIOTAPE_MAX_TAPE)
874 return -ENODEV;
875 if (!node)
876 return -ENODEV;
878 if (i >= viotape_numdev)
879 viotape_numdev = i + 1;
881 tape_device[i] = &vdev->dev;
882 viotape_unitinfo[i].rsrcname = of_get_property(node,
883 "linux,vio_rsrcname", NULL);
884 viotape_unitinfo[i].type = of_get_property(node, "linux,vio_type",
885 NULL);
886 viotape_unitinfo[i].model = of_get_property(node, "linux,vio_model",
887 NULL);
889 state[i].cur_part = 0;
890 for (j = 0; j < MAX_PARTITIONS; ++j)
891 state[i].part_stat_rwi[j] = VIOT_IDLE;
892 device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i), NULL,
893 "iseries!vt%d", i);
894 device_create(tape_class, NULL, MKDEV(VIOTAPE_MAJOR, i | 0x80), NULL,
895 "iseries!nvt%d", i);
896 printk(VIOTAPE_KERN_INFO "tape iseries/vt%d is iSeries "
897 "resource %10.10s type %4.4s, model %3.3s\n",
898 i, viotape_unitinfo[i].rsrcname,
899 viotape_unitinfo[i].type, viotape_unitinfo[i].model);
900 return 0;
903 static int viotape_remove(struct vio_dev *vdev)
905 int i = vdev->unit_address;
907 device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i | 0x80));
908 device_destroy(tape_class, MKDEV(VIOTAPE_MAJOR, i));
909 return 0;
913 * viotape_device_table: Used by vio.c to match devices that we
914 * support.
916 static struct vio_device_id viotape_device_table[] __devinitdata = {
917 { "byte", "IBM,iSeries-viotape" },
918 { "", "" }
920 MODULE_DEVICE_TABLE(vio, viotape_device_table);
922 static struct vio_driver viotape_driver = {
923 .id_table = viotape_device_table,
924 .probe = viotape_probe,
925 .remove = viotape_remove,
926 .driver = {
927 .name = "viotape",
928 .owner = THIS_MODULE,
933 int __init viotap_init(void)
935 int ret;
937 if (!firmware_has_feature(FW_FEATURE_ISERIES))
938 return -ENODEV;
940 op_struct_list = NULL;
941 if ((ret = add_op_structs(VIOTAPE_MAXREQ)) < 0) {
942 printk(VIOTAPE_KERN_WARN "couldn't allocate op structs\n");
943 return ret;
945 spin_lock_init(&op_struct_list_lock);
947 sema_init(&reqSem, VIOTAPE_MAXREQ);
949 if (viopath_hostLp == HvLpIndexInvalid) {
950 vio_set_hostlp();
951 if (viopath_hostLp == HvLpIndexInvalid) {
952 ret = -ENODEV;
953 goto clear_op;
957 ret = viopath_open(viopath_hostLp, viomajorsubtype_tape,
958 VIOTAPE_MAXREQ + 2);
959 if (ret) {
960 printk(VIOTAPE_KERN_WARN
961 "error on viopath_open to hostlp %d\n", ret);
962 ret = -EIO;
963 goto clear_op;
966 printk(VIOTAPE_KERN_INFO "vers " VIOTAPE_VERSION
967 ", hosting partition %d\n", viopath_hostLp);
969 vio_setHandler(viomajorsubtype_tape, vioHandleTapeEvent);
971 ret = register_chrdev(VIOTAPE_MAJOR, "viotape", &viotap_fops);
972 if (ret < 0) {
973 printk(VIOTAPE_KERN_WARN "Error registering viotape device\n");
974 goto clear_handler;
977 tape_class = class_create(THIS_MODULE, "tape");
978 if (IS_ERR(tape_class)) {
979 printk(VIOTAPE_KERN_WARN "Unable to allocat class\n");
980 ret = PTR_ERR(tape_class);
981 goto unreg_chrdev;
984 ret = vio_register_driver(&viotape_driver);
985 if (ret)
986 goto unreg_class;
988 proc_create("iSeries/viotape", S_IFREG|S_IRUGO, NULL,
989 &proc_viotape_operations);
991 return 0;
993 unreg_class:
994 class_destroy(tape_class);
995 unreg_chrdev:
996 unregister_chrdev(VIOTAPE_MAJOR, "viotape");
997 clear_handler:
998 vio_clearHandler(viomajorsubtype_tape);
999 viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1000 clear_op:
1001 clear_op_struct_pool();
1002 return ret;
1005 /* Give a new state to the tape object */
1006 static int chg_state(int index, unsigned char new_state, struct file *file)
1008 unsigned char *cur_state =
1009 &state[index].part_stat_rwi[state[index].cur_part];
1010 int rc = 0;
1012 /* if the same state, don't bother */
1013 if (*cur_state == new_state)
1014 return 0;
1016 /* write an EOF if changing from writing to some other state */
1017 if (*cur_state == VIOT_WRITING) {
1018 struct mtop write_eof = { MTWEOF, 1 };
1020 rc = viotap_ioctl(NULL, file, MTIOCTOP,
1021 (unsigned long)&write_eof);
1023 *cur_state = new_state;
1024 return rc;
1027 /* Cleanup */
1028 static void __exit viotap_exit(void)
1030 remove_proc_entry("iSeries/viotape", NULL);
1031 vio_unregister_driver(&viotape_driver);
1032 class_destroy(tape_class);
1033 unregister_chrdev(VIOTAPE_MAJOR, "viotape");
1034 viopath_close(viopath_hostLp, viomajorsubtype_tape, VIOTAPE_MAXREQ + 2);
1035 vio_clearHandler(viomajorsubtype_tape);
1036 clear_op_struct_pool();
1039 MODULE_LICENSE("GPL");
1040 module_init(viotap_init);
1041 module_exit(viotap_exit);