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[deliverable/linux.git] / drivers / scsi / sg.c
1 /*
2 * History:
3 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
4 * to allow user process control of SCSI devices.
5 * Development Sponsored by Killy Corp. NY NY
6 *
7 * Original driver (sg.c):
8 * Copyright (C) 1992 Lawrence Foard
9 * Version 2 and 3 extensions to driver:
10 * Copyright (C) 1998 - 2005 Douglas Gilbert
11 *
12 * Modified 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
18 *
19 */
20
21 static int sg_version_num = 30534; /* 2 digits for each component */
22 #define SG_VERSION_STR "3.5.34"
23
24 /*
25 * D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
26 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
27 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING
28 * (otherwise the macros compile to empty statements).
29 *
30 */
31 #include <linux/module.h>
32
33 #include <linux/fs.h>
34 #include <linux/kernel.h>
35 #include <linux/sched.h>
36 #include <linux/string.h>
37 #include <linux/mm.h>
38 #include <linux/errno.h>
39 #include <linux/mtio.h>
40 #include <linux/ioctl.h>
41 #include <linux/fcntl.h>
42 #include <linux/init.h>
43 #include <linux/poll.h>
44 #include <linux/moduleparam.h>
45 #include <linux/cdev.h>
46 #include <linux/idr.h>
47 #include <linux/seq_file.h>
48 #include <linux/blkdev.h>
49 #include <linux/delay.h>
50 #include <linux/scatterlist.h>
51 #include <linux/blktrace_api.h>
52
53 #include "scsi.h"
54 #include <scsi/scsi_dbg.h>
55 #include <scsi/scsi_host.h>
56 #include <scsi/scsi_driver.h>
57 #include <scsi/scsi_ioctl.h>
58 #include <scsi/sg.h>
59
60 #include "scsi_logging.h"
61
62 #ifdef CONFIG_SCSI_PROC_FS
63 #include <linux/proc_fs.h>
64 static char *sg_version_date = "20061027";
65
66 static int sg_proc_init(void);
67 static void sg_proc_cleanup(void);
68 #endif
69
70 #define SG_ALLOW_DIO_DEF 0
71 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
72
73 #define SG_MAX_DEVS 32768
74
75 /*
76 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
77 * Then when using 32 bit integers x * m may overflow during the calculation.
78 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
79 * calculates the same, but prevents the overflow when both m and d
80 * are "small" numbers (like HZ and USER_HZ).
81 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
82 * in 32 bits.
83 */
84 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
85
86 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
87
88 int sg_big_buff = SG_DEF_RESERVED_SIZE;
89 /* N.B. This variable is readable and writeable via
90 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
91 of this size (or less if there is not enough memory) will be reserved
92 for use by this file descriptor. [Deprecated usage: this variable is also
93 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
94 the kernel (i.e. it is not a module).] */
95 static int def_reserved_size = -1; /* picks up init parameter */
96 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
97
98 static int scatter_elem_sz = SG_SCATTER_SZ;
99 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
100
101 #define SG_SECTOR_SZ 512
102 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
103
104 static int sg_add(struct device *, struct class_interface *);
105 static void sg_remove(struct device *, struct class_interface *);
106
107 static DEFINE_IDR(sg_index_idr);
108 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
109 file descriptor list for device */
110
111 static struct class_interface sg_interface = {
112 .add_dev = sg_add,
113 .remove_dev = sg_remove,
114 };
115
116 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
117 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
118 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
119 unsigned bufflen; /* Size of (aggregate) data buffer */
120 unsigned b_malloc_len; /* actual len malloc'ed in buffer */
121 struct scatterlist *buffer;/* scatter list */
122 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
123 unsigned char cmd_opcode; /* first byte of command */
124 } Sg_scatter_hold;
125
126 struct sg_device; /* forward declarations */
127 struct sg_fd;
128
129 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
130 struct sg_request *nextrp; /* NULL -> tail request (slist) */
131 struct sg_fd *parentfp; /* NULL -> not in use */
132 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
133 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
134 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
135 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
136 char orphan; /* 1 -> drop on sight, 0 -> normal */
137 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
138 volatile char done; /* 0->before bh, 1->before read, 2->read */
139 } Sg_request;
140
141 typedef struct sg_fd { /* holds the state of a file descriptor */
142 struct sg_fd *nextfp; /* NULL when last opened fd on this device */
143 struct sg_device *parentdp; /* owning device */
144 wait_queue_head_t read_wait; /* queue read until command done */
145 rwlock_t rq_list_lock; /* protect access to list in req_arr */
146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
149 unsigned save_scat_len; /* original length of trunc. scat. element */
150 Sg_request *headrp; /* head of request slist, NULL->empty */
151 struct fasync_struct *async_qp; /* used by asynchronous notification */
152 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
153 char low_dma; /* as in parent but possibly overridden to 1 */
154 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
155 volatile char closed; /* 1 -> fd closed but request(s) outstanding */
156 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
157 char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
158 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
159 char mmap_called; /* 0 -> mmap() never called on this fd */
160 } Sg_fd;
161
162 typedef struct sg_device { /* holds the state of each scsi generic device */
163 struct scsi_device *device;
164 wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
165 int sg_tablesize; /* adapter's max scatter-gather table size */
166 u32 index; /* device index number */
167 Sg_fd *headfp; /* first open fd belonging to this device */
168 volatile char detached; /* 0->attached, 1->detached pending removal */
169 volatile char exclude; /* opened for exclusive access */
170 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
171 struct gendisk *disk;
172 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
173 } Sg_device;
174
175 static int sg_fasync(int fd, struct file *filp, int mode);
176 /* tasklet or soft irq callback */
177 static void sg_cmd_done(void *data, char *sense, int result, int resid);
178 static int sg_start_req(Sg_request * srp);
179 static void sg_finish_rem_req(Sg_request * srp);
180 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
181 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
182 int tablesize);
183 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
184 Sg_request * srp);
185 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
186 const char __user *buf, size_t count, int blocking,
187 int read_only, Sg_request **o_srp);
188 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
189 unsigned char *cmnd, int timeout, int blocking);
190 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
191 int wr_xf, int *countp, unsigned char __user **up);
192 static int sg_write_xfer(Sg_request * srp);
193 static int sg_read_xfer(Sg_request * srp);
194 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
195 static void sg_remove_scat(Sg_scatter_hold * schp);
196 static void sg_build_reserve(Sg_fd * sfp, int req_size);
197 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
198 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
199 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
200 static void sg_page_free(struct page *page, int size);
201 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
202 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
203 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
204 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
205 static Sg_request *sg_add_request(Sg_fd * sfp);
206 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
207 static int sg_res_in_use(Sg_fd * sfp);
208 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
209 static Sg_device *sg_get_dev(int dev);
210 #ifdef CONFIG_SCSI_PROC_FS
211 static int sg_last_dev(void);
212 #endif
213
214 #define SZ_SG_HEADER sizeof(struct sg_header)
215 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
216 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
217 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
218
219 static int
220 sg_open(struct inode *inode, struct file *filp)
221 {
222 int dev = iminor(inode);
223 int flags = filp->f_flags;
224 struct request_queue *q;
225 Sg_device *sdp;
226 Sg_fd *sfp;
227 int res;
228 int retval;
229
230 nonseekable_open(inode, filp);
231 SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
232 sdp = sg_get_dev(dev);
233 if ((!sdp) || (!sdp->device))
234 return -ENXIO;
235 if (sdp->detached)
236 return -ENODEV;
237
238 /* This driver's module count bumped by fops_get in <linux/fs.h> */
239 /* Prevent the device driver from vanishing while we sleep */
240 retval = scsi_device_get(sdp->device);
241 if (retval)
242 return retval;
243
244 if (!((flags & O_NONBLOCK) ||
245 scsi_block_when_processing_errors(sdp->device))) {
246 retval = -ENXIO;
247 /* we are in error recovery for this device */
248 goto error_out;
249 }
250
251 if (flags & O_EXCL) {
252 if (O_RDONLY == (flags & O_ACCMODE)) {
253 retval = -EPERM; /* Can't lock it with read only access */
254 goto error_out;
255 }
256 if (sdp->headfp && (flags & O_NONBLOCK)) {
257 retval = -EBUSY;
258 goto error_out;
259 }
260 res = 0;
261 __wait_event_interruptible(sdp->o_excl_wait,
262 ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
263 if (res) {
264 retval = res; /* -ERESTARTSYS because signal hit process */
265 goto error_out;
266 }
267 } else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */
268 if (flags & O_NONBLOCK) {
269 retval = -EBUSY;
270 goto error_out;
271 }
272 res = 0;
273 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
274 res);
275 if (res) {
276 retval = res; /* -ERESTARTSYS because signal hit process */
277 goto error_out;
278 }
279 }
280 if (sdp->detached) {
281 retval = -ENODEV;
282 goto error_out;
283 }
284 if (!sdp->headfp) { /* no existing opens on this device */
285 sdp->sgdebug = 0;
286 q = sdp->device->request_queue;
287 sdp->sg_tablesize = min(q->max_hw_segments,
288 q->max_phys_segments);
289 }
290 if ((sfp = sg_add_sfp(sdp, dev)))
291 filp->private_data = sfp;
292 else {
293 if (flags & O_EXCL)
294 sdp->exclude = 0; /* undo if error */
295 retval = -ENOMEM;
296 goto error_out;
297 }
298 return 0;
299
300 error_out:
301 scsi_device_put(sdp->device);
302 return retval;
303 }
304
305 /* Following function was formerly called 'sg_close' */
306 static int
307 sg_release(struct inode *inode, struct file *filp)
308 {
309 Sg_device *sdp;
310 Sg_fd *sfp;
311
312 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
313 return -ENXIO;
314 SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
315 sg_fasync(-1, filp, 0); /* remove filp from async notification list */
316 if (0 == sg_remove_sfp(sdp, sfp)) { /* Returns 1 when sdp gone */
317 if (!sdp->detached) {
318 scsi_device_put(sdp->device);
319 }
320 sdp->exclude = 0;
321 wake_up_interruptible(&sdp->o_excl_wait);
322 }
323 return 0;
324 }
325
326 static ssize_t
327 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
328 {
329 Sg_device *sdp;
330 Sg_fd *sfp;
331 Sg_request *srp;
332 int req_pack_id = -1;
333 sg_io_hdr_t *hp;
334 struct sg_header *old_hdr = NULL;
335 int retval = 0;
336
337 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
338 return -ENXIO;
339 SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
340 sdp->disk->disk_name, (int) count));
341
342 if (!access_ok(VERIFY_WRITE, buf, count))
343 return -EFAULT;
344 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
345 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
346 if (!old_hdr)
347 return -ENOMEM;
348 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
349 retval = -EFAULT;
350 goto free_old_hdr;
351 }
352 if (old_hdr->reply_len < 0) {
353 if (count >= SZ_SG_IO_HDR) {
354 sg_io_hdr_t *new_hdr;
355 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
356 if (!new_hdr) {
357 retval = -ENOMEM;
358 goto free_old_hdr;
359 }
360 retval =__copy_from_user
361 (new_hdr, buf, SZ_SG_IO_HDR);
362 req_pack_id = new_hdr->pack_id;
363 kfree(new_hdr);
364 if (retval) {
365 retval = -EFAULT;
366 goto free_old_hdr;
367 }
368 }
369 } else
370 req_pack_id = old_hdr->pack_id;
371 }
372 srp = sg_get_rq_mark(sfp, req_pack_id);
373 if (!srp) { /* now wait on packet to arrive */
374 if (sdp->detached) {
375 retval = -ENODEV;
376 goto free_old_hdr;
377 }
378 if (filp->f_flags & O_NONBLOCK) {
379 retval = -EAGAIN;
380 goto free_old_hdr;
381 }
382 while (1) {
383 retval = 0; /* following macro beats race condition */
384 __wait_event_interruptible(sfp->read_wait,
385 (sdp->detached ||
386 (srp = sg_get_rq_mark(sfp, req_pack_id))),
387 retval);
388 if (sdp->detached) {
389 retval = -ENODEV;
390 goto free_old_hdr;
391 }
392 if (0 == retval)
393 break;
394
395 /* -ERESTARTSYS as signal hit process */
396 goto free_old_hdr;
397 }
398 }
399 if (srp->header.interface_id != '\0') {
400 retval = sg_new_read(sfp, buf, count, srp);
401 goto free_old_hdr;
402 }
403
404 hp = &srp->header;
405 if (old_hdr == NULL) {
406 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
407 if (! old_hdr) {
408 retval = -ENOMEM;
409 goto free_old_hdr;
410 }
411 }
412 memset(old_hdr, 0, SZ_SG_HEADER);
413 old_hdr->reply_len = (int) hp->timeout;
414 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
415 old_hdr->pack_id = hp->pack_id;
416 old_hdr->twelve_byte =
417 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
418 old_hdr->target_status = hp->masked_status;
419 old_hdr->host_status = hp->host_status;
420 old_hdr->driver_status = hp->driver_status;
421 if ((CHECK_CONDITION & hp->masked_status) ||
422 (DRIVER_SENSE & hp->driver_status))
423 memcpy(old_hdr->sense_buffer, srp->sense_b,
424 sizeof (old_hdr->sense_buffer));
425 switch (hp->host_status) {
426 /* This setup of 'result' is for backward compatibility and is best
427 ignored by the user who should use target, host + driver status */
428 case DID_OK:
429 case DID_PASSTHROUGH:
430 case DID_SOFT_ERROR:
431 old_hdr->result = 0;
432 break;
433 case DID_NO_CONNECT:
434 case DID_BUS_BUSY:
435 case DID_TIME_OUT:
436 old_hdr->result = EBUSY;
437 break;
438 case DID_BAD_TARGET:
439 case DID_ABORT:
440 case DID_PARITY:
441 case DID_RESET:
442 case DID_BAD_INTR:
443 old_hdr->result = EIO;
444 break;
445 case DID_ERROR:
446 old_hdr->result = (srp->sense_b[0] == 0 &&
447 hp->masked_status == GOOD) ? 0 : EIO;
448 break;
449 default:
450 old_hdr->result = EIO;
451 break;
452 }
453
454 /* Now copy the result back to the user buffer. */
455 if (count >= SZ_SG_HEADER) {
456 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
457 retval = -EFAULT;
458 goto free_old_hdr;
459 }
460 buf += SZ_SG_HEADER;
461 if (count > old_hdr->reply_len)
462 count = old_hdr->reply_len;
463 if (count > SZ_SG_HEADER) {
464 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
465 retval = -EFAULT;
466 goto free_old_hdr;
467 }
468 }
469 } else
470 count = (old_hdr->result == 0) ? 0 : -EIO;
471 sg_finish_rem_req(srp);
472 retval = count;
473 free_old_hdr:
474 kfree(old_hdr);
475 return retval;
476 }
477
478 static ssize_t
479 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
480 {
481 sg_io_hdr_t *hp = &srp->header;
482 int err = 0;
483 int len;
484
485 if (count < SZ_SG_IO_HDR) {
486 err = -EINVAL;
487 goto err_out;
488 }
489 hp->sb_len_wr = 0;
490 if ((hp->mx_sb_len > 0) && hp->sbp) {
491 if ((CHECK_CONDITION & hp->masked_status) ||
492 (DRIVER_SENSE & hp->driver_status)) {
493 int sb_len = SCSI_SENSE_BUFFERSIZE;
494 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
495 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
496 len = (len > sb_len) ? sb_len : len;
497 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
498 err = -EFAULT;
499 goto err_out;
500 }
501 hp->sb_len_wr = len;
502 }
503 }
504 if (hp->masked_status || hp->host_status || hp->driver_status)
505 hp->info |= SG_INFO_CHECK;
506 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
507 err = -EFAULT;
508 goto err_out;
509 }
510 err = sg_read_xfer(srp);
511 err_out:
512 sg_finish_rem_req(srp);
513 return (0 == err) ? count : err;
514 }
515
516 static ssize_t
517 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
518 {
519 int mxsize, cmd_size, k;
520 int input_size, blocking;
521 unsigned char opcode;
522 Sg_device *sdp;
523 Sg_fd *sfp;
524 Sg_request *srp;
525 struct sg_header old_hdr;
526 sg_io_hdr_t *hp;
527 unsigned char cmnd[MAX_COMMAND_SIZE];
528
529 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
530 return -ENXIO;
531 SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
532 sdp->disk->disk_name, (int) count));
533 if (sdp->detached)
534 return -ENODEV;
535 if (!((filp->f_flags & O_NONBLOCK) ||
536 scsi_block_when_processing_errors(sdp->device)))
537 return -ENXIO;
538
539 if (!access_ok(VERIFY_READ, buf, count))
540 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
541 if (count < SZ_SG_HEADER)
542 return -EIO;
543 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
544 return -EFAULT;
545 blocking = !(filp->f_flags & O_NONBLOCK);
546 if (old_hdr.reply_len < 0)
547 return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
548 if (count < (SZ_SG_HEADER + 6))
549 return -EIO; /* The minimum scsi command length is 6 bytes. */
550
551 if (!(srp = sg_add_request(sfp))) {
552 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
553 return -EDOM;
554 }
555 buf += SZ_SG_HEADER;
556 __get_user(opcode, buf);
557 if (sfp->next_cmd_len > 0) {
558 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
559 SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
560 sfp->next_cmd_len = 0;
561 sg_remove_request(sfp, srp);
562 return -EIO;
563 }
564 cmd_size = sfp->next_cmd_len;
565 sfp->next_cmd_len = 0; /* reset so only this write() effected */
566 } else {
567 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
568 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
569 cmd_size = 12;
570 }
571 SCSI_LOG_TIMEOUT(4, printk(
572 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
573 /* Determine buffer size. */
574 input_size = count - cmd_size;
575 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
576 mxsize -= SZ_SG_HEADER;
577 input_size -= SZ_SG_HEADER;
578 if (input_size < 0) {
579 sg_remove_request(sfp, srp);
580 return -EIO; /* User did not pass enough bytes for this command. */
581 }
582 hp = &srp->header;
583 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
584 hp->cmd_len = (unsigned char) cmd_size;
585 hp->iovec_count = 0;
586 hp->mx_sb_len = 0;
587 if (input_size > 0)
588 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
589 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
590 else
591 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
592 hp->dxfer_len = mxsize;
593 hp->dxferp = (char __user *)buf + cmd_size;
594 hp->sbp = NULL;
595 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
596 hp->flags = input_size; /* structure abuse ... */
597 hp->pack_id = old_hdr.pack_id;
598 hp->usr_ptr = NULL;
599 if (__copy_from_user(cmnd, buf, cmd_size))
600 return -EFAULT;
601 /*
602 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
603 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
604 * is a non-zero input_size, so emit a warning.
605 */
606 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
607 static char cmd[TASK_COMM_LEN];
608 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
609 printk(KERN_WARNING
610 "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
611 "guessing data in;\n" KERN_WARNING " "
612 "program %s not setting count and/or reply_len properly\n",
613 old_hdr.reply_len - (int)SZ_SG_HEADER,
614 input_size, (unsigned int) cmnd[0],
615 current->comm);
616 strcpy(cmd, current->comm);
617 }
618 }
619 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
620 return (k < 0) ? k : count;
621 }
622
623 static ssize_t
624 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
625 size_t count, int blocking, int read_only,
626 Sg_request **o_srp)
627 {
628 int k;
629 Sg_request *srp;
630 sg_io_hdr_t *hp;
631 unsigned char cmnd[MAX_COMMAND_SIZE];
632 int timeout;
633 unsigned long ul_timeout;
634
635 if (count < SZ_SG_IO_HDR)
636 return -EINVAL;
637 if (!access_ok(VERIFY_READ, buf, count))
638 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
639
640 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
641 if (!(srp = sg_add_request(sfp))) {
642 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
643 return -EDOM;
644 }
645 hp = &srp->header;
646 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
647 sg_remove_request(sfp, srp);
648 return -EFAULT;
649 }
650 if (hp->interface_id != 'S') {
651 sg_remove_request(sfp, srp);
652 return -ENOSYS;
653 }
654 if (hp->flags & SG_FLAG_MMAP_IO) {
655 if (hp->dxfer_len > sfp->reserve.bufflen) {
656 sg_remove_request(sfp, srp);
657 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
658 }
659 if (hp->flags & SG_FLAG_DIRECT_IO) {
660 sg_remove_request(sfp, srp);
661 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
662 }
663 if (sg_res_in_use(sfp)) {
664 sg_remove_request(sfp, srp);
665 return -EBUSY; /* reserve buffer already being used */
666 }
667 }
668 ul_timeout = msecs_to_jiffies(srp->header.timeout);
669 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
670 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
671 sg_remove_request(sfp, srp);
672 return -EMSGSIZE;
673 }
674 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
675 sg_remove_request(sfp, srp);
676 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
677 }
678 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
679 sg_remove_request(sfp, srp);
680 return -EFAULT;
681 }
682 if (read_only && (!blk_verify_command(file, cmnd))) {
683 sg_remove_request(sfp, srp);
684 return -EPERM;
685 }
686 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
687 if (k < 0)
688 return k;
689 if (o_srp)
690 *o_srp = srp;
691 return count;
692 }
693
694 static int
695 sg_common_write(Sg_fd * sfp, Sg_request * srp,
696 unsigned char *cmnd, int timeout, int blocking)
697 {
698 int k, data_dir;
699 Sg_device *sdp = sfp->parentdp;
700 sg_io_hdr_t *hp = &srp->header;
701
702 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
703 hp->status = 0;
704 hp->masked_status = 0;
705 hp->msg_status = 0;
706 hp->info = 0;
707 hp->host_status = 0;
708 hp->driver_status = 0;
709 hp->resid = 0;
710 SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
711 (int) cmnd[0], (int) hp->cmd_len));
712
713 if ((k = sg_start_req(srp))) {
714 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
715 sg_finish_rem_req(srp);
716 return k; /* probably out of space --> ENOMEM */
717 }
718 if ((k = sg_write_xfer(srp))) {
719 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
720 sg_finish_rem_req(srp);
721 return k;
722 }
723 if (sdp->detached) {
724 sg_finish_rem_req(srp);
725 return -ENODEV;
726 }
727
728 switch (hp->dxfer_direction) {
729 case SG_DXFER_TO_FROM_DEV:
730 case SG_DXFER_FROM_DEV:
731 data_dir = DMA_FROM_DEVICE;
732 break;
733 case SG_DXFER_TO_DEV:
734 data_dir = DMA_TO_DEVICE;
735 break;
736 case SG_DXFER_UNKNOWN:
737 data_dir = DMA_BIDIRECTIONAL;
738 break;
739 default:
740 data_dir = DMA_NONE;
741 break;
742 }
743 hp->duration = jiffies_to_msecs(jiffies);
744 /* Now send everything of to mid-level. The next time we hear about this
745 packet is when sg_cmd_done() is called (i.e. a callback). */
746 if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
747 hp->dxfer_len, srp->data.k_use_sg, timeout,
748 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
749 GFP_ATOMIC)) {
750 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
751 /*
752 * most likely out of mem, but could also be a bad map
753 */
754 sg_finish_rem_req(srp);
755 return -ENOMEM;
756 } else
757 return 0;
758 }
759
760 static int
761 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
762 {
763 unsigned long iflags;
764 int done;
765
766 read_lock_irqsave(&sfp->rq_list_lock, iflags);
767 done = srp->done;
768 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
769 return done;
770 }
771
772 static int
773 sg_ioctl(struct inode *inode, struct file *filp,
774 unsigned int cmd_in, unsigned long arg)
775 {
776 void __user *p = (void __user *)arg;
777 int __user *ip = p;
778 int result, val, read_only;
779 Sg_device *sdp;
780 Sg_fd *sfp;
781 Sg_request *srp;
782 unsigned long iflags;
783
784 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
785 return -ENXIO;
786 SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
787 sdp->disk->disk_name, (int) cmd_in));
788 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
789
790 switch (cmd_in) {
791 case SG_IO:
792 {
793 int blocking = 1; /* ignore O_NONBLOCK flag */
794
795 if (sdp->detached)
796 return -ENODEV;
797 if (!scsi_block_when_processing_errors(sdp->device))
798 return -ENXIO;
799 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
800 return -EFAULT;
801 result =
802 sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
803 blocking, read_only, &srp);
804 if (result < 0)
805 return result;
806 srp->sg_io_owned = 1;
807 while (1) {
808 result = 0; /* following macro to beat race condition */
809 __wait_event_interruptible(sfp->read_wait,
810 (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
811 result);
812 if (sdp->detached)
813 return -ENODEV;
814 if (sfp->closed)
815 return 0; /* request packet dropped already */
816 if (0 == result)
817 break;
818 srp->orphan = 1;
819 return result; /* -ERESTARTSYS because signal hit process */
820 }
821 write_lock_irqsave(&sfp->rq_list_lock, iflags);
822 srp->done = 2;
823 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
824 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
825 return (result < 0) ? result : 0;
826 }
827 case SG_SET_TIMEOUT:
828 result = get_user(val, ip);
829 if (result)
830 return result;
831 if (val < 0)
832 return -EIO;
833 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
834 val = MULDIV (INT_MAX, USER_HZ, HZ);
835 sfp->timeout_user = val;
836 sfp->timeout = MULDIV (val, HZ, USER_HZ);
837
838 return 0;
839 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
840 /* strange ..., for backward compatibility */
841 return sfp->timeout_user;
842 case SG_SET_FORCE_LOW_DMA:
843 result = get_user(val, ip);
844 if (result)
845 return result;
846 if (val) {
847 sfp->low_dma = 1;
848 if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
849 val = (int) sfp->reserve.bufflen;
850 sg_remove_scat(&sfp->reserve);
851 sg_build_reserve(sfp, val);
852 }
853 } else {
854 if (sdp->detached)
855 return -ENODEV;
856 sfp->low_dma = sdp->device->host->unchecked_isa_dma;
857 }
858 return 0;
859 case SG_GET_LOW_DMA:
860 return put_user((int) sfp->low_dma, ip);
861 case SG_GET_SCSI_ID:
862 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
863 return -EFAULT;
864 else {
865 sg_scsi_id_t __user *sg_idp = p;
866
867 if (sdp->detached)
868 return -ENODEV;
869 __put_user((int) sdp->device->host->host_no,
870 &sg_idp->host_no);
871 __put_user((int) sdp->device->channel,
872 &sg_idp->channel);
873 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
874 __put_user((int) sdp->device->lun, &sg_idp->lun);
875 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
876 __put_user((short) sdp->device->host->cmd_per_lun,
877 &sg_idp->h_cmd_per_lun);
878 __put_user((short) sdp->device->queue_depth,
879 &sg_idp->d_queue_depth);
880 __put_user(0, &sg_idp->unused[0]);
881 __put_user(0, &sg_idp->unused[1]);
882 return 0;
883 }
884 case SG_SET_FORCE_PACK_ID:
885 result = get_user(val, ip);
886 if (result)
887 return result;
888 sfp->force_packid = val ? 1 : 0;
889 return 0;
890 case SG_GET_PACK_ID:
891 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
892 return -EFAULT;
893 read_lock_irqsave(&sfp->rq_list_lock, iflags);
894 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
895 if ((1 == srp->done) && (!srp->sg_io_owned)) {
896 read_unlock_irqrestore(&sfp->rq_list_lock,
897 iflags);
898 __put_user(srp->header.pack_id, ip);
899 return 0;
900 }
901 }
902 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
903 __put_user(-1, ip);
904 return 0;
905 case SG_GET_NUM_WAITING:
906 read_lock_irqsave(&sfp->rq_list_lock, iflags);
907 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
908 if ((1 == srp->done) && (!srp->sg_io_owned))
909 ++val;
910 }
911 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
912 return put_user(val, ip);
913 case SG_GET_SG_TABLESIZE:
914 return put_user(sdp->sg_tablesize, ip);
915 case SG_SET_RESERVED_SIZE:
916 result = get_user(val, ip);
917 if (result)
918 return result;
919 if (val < 0)
920 return -EINVAL;
921 val = min_t(int, val,
922 sdp->device->request_queue->max_sectors * 512);
923 if (val != sfp->reserve.bufflen) {
924 if (sg_res_in_use(sfp) || sfp->mmap_called)
925 return -EBUSY;
926 sg_remove_scat(&sfp->reserve);
927 sg_build_reserve(sfp, val);
928 }
929 return 0;
930 case SG_GET_RESERVED_SIZE:
931 val = min_t(int, sfp->reserve.bufflen,
932 sdp->device->request_queue->max_sectors * 512);
933 return put_user(val, ip);
934 case SG_SET_COMMAND_Q:
935 result = get_user(val, ip);
936 if (result)
937 return result;
938 sfp->cmd_q = val ? 1 : 0;
939 return 0;
940 case SG_GET_COMMAND_Q:
941 return put_user((int) sfp->cmd_q, ip);
942 case SG_SET_KEEP_ORPHAN:
943 result = get_user(val, ip);
944 if (result)
945 return result;
946 sfp->keep_orphan = val;
947 return 0;
948 case SG_GET_KEEP_ORPHAN:
949 return put_user((int) sfp->keep_orphan, ip);
950 case SG_NEXT_CMD_LEN:
951 result = get_user(val, ip);
952 if (result)
953 return result;
954 sfp->next_cmd_len = (val > 0) ? val : 0;
955 return 0;
956 case SG_GET_VERSION_NUM:
957 return put_user(sg_version_num, ip);
958 case SG_GET_ACCESS_COUNT:
959 /* faked - we don't have a real access count anymore */
960 val = (sdp->device ? 1 : 0);
961 return put_user(val, ip);
962 case SG_GET_REQUEST_TABLE:
963 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
964 return -EFAULT;
965 else {
966 sg_req_info_t *rinfo;
967 unsigned int ms;
968
969 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
970 GFP_KERNEL);
971 if (!rinfo)
972 return -ENOMEM;
973 read_lock_irqsave(&sfp->rq_list_lock, iflags);
974 for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
975 ++val, srp = srp ? srp->nextrp : srp) {
976 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
977 if (srp) {
978 rinfo[val].req_state = srp->done + 1;
979 rinfo[val].problem =
980 srp->header.masked_status &
981 srp->header.host_status &
982 srp->header.driver_status;
983 if (srp->done)
984 rinfo[val].duration =
985 srp->header.duration;
986 else {
987 ms = jiffies_to_msecs(jiffies);
988 rinfo[val].duration =
989 (ms > srp->header.duration) ?
990 (ms - srp->header.duration) : 0;
991 }
992 rinfo[val].orphan = srp->orphan;
993 rinfo[val].sg_io_owned =
994 srp->sg_io_owned;
995 rinfo[val].pack_id =
996 srp->header.pack_id;
997 rinfo[val].usr_ptr =
998 srp->header.usr_ptr;
999 }
1000 }
1001 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1002 result = __copy_to_user(p, rinfo,
1003 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1004 result = result ? -EFAULT : 0;
1005 kfree(rinfo);
1006 return result;
1007 }
1008 case SG_EMULATED_HOST:
1009 if (sdp->detached)
1010 return -ENODEV;
1011 return put_user(sdp->device->host->hostt->emulated, ip);
1012 case SG_SCSI_RESET:
1013 if (sdp->detached)
1014 return -ENODEV;
1015 if (filp->f_flags & O_NONBLOCK) {
1016 if (scsi_host_in_recovery(sdp->device->host))
1017 return -EBUSY;
1018 } else if (!scsi_block_when_processing_errors(sdp->device))
1019 return -EBUSY;
1020 result = get_user(val, ip);
1021 if (result)
1022 return result;
1023 if (SG_SCSI_RESET_NOTHING == val)
1024 return 0;
1025 switch (val) {
1026 case SG_SCSI_RESET_DEVICE:
1027 val = SCSI_TRY_RESET_DEVICE;
1028 break;
1029 case SG_SCSI_RESET_BUS:
1030 val = SCSI_TRY_RESET_BUS;
1031 break;
1032 case SG_SCSI_RESET_HOST:
1033 val = SCSI_TRY_RESET_HOST;
1034 break;
1035 default:
1036 return -EINVAL;
1037 }
1038 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1039 return -EACCES;
1040 return (scsi_reset_provider(sdp->device, val) ==
1041 SUCCESS) ? 0 : -EIO;
1042 case SCSI_IOCTL_SEND_COMMAND:
1043 if (sdp->detached)
1044 return -ENODEV;
1045 if (read_only) {
1046 unsigned char opcode = WRITE_6;
1047 Scsi_Ioctl_Command __user *siocp = p;
1048
1049 if (copy_from_user(&opcode, siocp->data, 1))
1050 return -EFAULT;
1051 if (!blk_verify_command(filp, &opcode))
1052 return -EPERM;
1053 }
1054 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1055 case SG_SET_DEBUG:
1056 result = get_user(val, ip);
1057 if (result)
1058 return result;
1059 sdp->sgdebug = (char) val;
1060 return 0;
1061 case SCSI_IOCTL_GET_IDLUN:
1062 case SCSI_IOCTL_GET_BUS_NUMBER:
1063 case SCSI_IOCTL_PROBE_HOST:
1064 case SG_GET_TRANSFORM:
1065 if (sdp->detached)
1066 return -ENODEV;
1067 return scsi_ioctl(sdp->device, cmd_in, p);
1068 case BLKSECTGET:
1069 return put_user(sdp->device->request_queue->max_sectors * 512,
1070 ip);
1071 case BLKTRACESETUP:
1072 return blk_trace_setup(sdp->device->request_queue,
1073 sdp->disk->disk_name,
1074 sdp->device->sdev_gendev.devt,
1075 (char *)arg);
1076 case BLKTRACESTART:
1077 return blk_trace_startstop(sdp->device->request_queue, 1);
1078 case BLKTRACESTOP:
1079 return blk_trace_startstop(sdp->device->request_queue, 0);
1080 case BLKTRACETEARDOWN:
1081 return blk_trace_remove(sdp->device->request_queue);
1082 default:
1083 if (read_only)
1084 return -EPERM; /* don't know so take safe approach */
1085 return scsi_ioctl(sdp->device, cmd_in, p);
1086 }
1087 }
1088
1089 #ifdef CONFIG_COMPAT
1090 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1091 {
1092 Sg_device *sdp;
1093 Sg_fd *sfp;
1094 struct scsi_device *sdev;
1095
1096 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1097 return -ENXIO;
1098
1099 sdev = sdp->device;
1100 if (sdev->host->hostt->compat_ioctl) {
1101 int ret;
1102
1103 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1104
1105 return ret;
1106 }
1107
1108 return -ENOIOCTLCMD;
1109 }
1110 #endif
1111
1112 static unsigned int
1113 sg_poll(struct file *filp, poll_table * wait)
1114 {
1115 unsigned int res = 0;
1116 Sg_device *sdp;
1117 Sg_fd *sfp;
1118 Sg_request *srp;
1119 int count = 0;
1120 unsigned long iflags;
1121
1122 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1123 || sfp->closed)
1124 return POLLERR;
1125 poll_wait(filp, &sfp->read_wait, wait);
1126 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1127 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1128 /* if any read waiting, flag it */
1129 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1130 res = POLLIN | POLLRDNORM;
1131 ++count;
1132 }
1133 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1134
1135 if (sdp->detached)
1136 res |= POLLHUP;
1137 else if (!sfp->cmd_q) {
1138 if (0 == count)
1139 res |= POLLOUT | POLLWRNORM;
1140 } else if (count < SG_MAX_QUEUE)
1141 res |= POLLOUT | POLLWRNORM;
1142 SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1143 sdp->disk->disk_name, (int) res));
1144 return res;
1145 }
1146
1147 static int
1148 sg_fasync(int fd, struct file *filp, int mode)
1149 {
1150 int retval;
1151 Sg_device *sdp;
1152 Sg_fd *sfp;
1153
1154 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1155 return -ENXIO;
1156 SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1157 sdp->disk->disk_name, mode));
1158
1159 retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1160 return (retval < 0) ? retval : 0;
1161 }
1162
1163 static int
1164 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1165 {
1166 Sg_fd *sfp;
1167 unsigned long offset, len, sa;
1168 Sg_scatter_hold *rsv_schp;
1169 struct scatterlist *sg;
1170 int k;
1171
1172 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1173 return VM_FAULT_SIGBUS;
1174 rsv_schp = &sfp->reserve;
1175 offset = vmf->pgoff << PAGE_SHIFT;
1176 if (offset >= rsv_schp->bufflen)
1177 return VM_FAULT_SIGBUS;
1178 SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1179 offset, rsv_schp->k_use_sg));
1180 sg = rsv_schp->buffer;
1181 sa = vma->vm_start;
1182 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1183 ++k, sg = sg_next(sg)) {
1184 len = vma->vm_end - sa;
1185 len = (len < sg->length) ? len : sg->length;
1186 if (offset < len) {
1187 struct page *page;
1188 page = virt_to_page(page_address(sg_page(sg)) + offset);
1189 get_page(page); /* increment page count */
1190 vmf->page = page;
1191 return 0; /* success */
1192 }
1193 sa += len;
1194 offset -= len;
1195 }
1196
1197 return VM_FAULT_SIGBUS;
1198 }
1199
1200 static struct vm_operations_struct sg_mmap_vm_ops = {
1201 .fault = sg_vma_fault,
1202 };
1203
1204 static int
1205 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1206 {
1207 Sg_fd *sfp;
1208 unsigned long req_sz, len, sa;
1209 Sg_scatter_hold *rsv_schp;
1210 int k;
1211 struct scatterlist *sg;
1212
1213 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1214 return -ENXIO;
1215 req_sz = vma->vm_end - vma->vm_start;
1216 SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1217 (void *) vma->vm_start, (int) req_sz));
1218 if (vma->vm_pgoff)
1219 return -EINVAL; /* want no offset */
1220 rsv_schp = &sfp->reserve;
1221 if (req_sz > rsv_schp->bufflen)
1222 return -ENOMEM; /* cannot map more than reserved buffer */
1223
1224 sa = vma->vm_start;
1225 sg = rsv_schp->buffer;
1226 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1227 ++k, sg = sg_next(sg)) {
1228 len = vma->vm_end - sa;
1229 len = (len < sg->length) ? len : sg->length;
1230 sa += len;
1231 }
1232
1233 sfp->mmap_called = 1;
1234 vma->vm_flags |= VM_RESERVED;
1235 vma->vm_private_data = sfp;
1236 vma->vm_ops = &sg_mmap_vm_ops;
1237 return 0;
1238 }
1239
1240 /* This function is a "bottom half" handler that is called by the
1241 * mid level when a command is completed (or has failed). */
1242 static void
1243 sg_cmd_done(void *data, char *sense, int result, int resid)
1244 {
1245 Sg_request *srp = data;
1246 Sg_device *sdp = NULL;
1247 Sg_fd *sfp;
1248 unsigned long iflags;
1249 unsigned int ms;
1250
1251 if (NULL == srp) {
1252 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1253 return;
1254 }
1255 sfp = srp->parentfp;
1256 if (sfp)
1257 sdp = sfp->parentdp;
1258 if ((NULL == sdp) || sdp->detached) {
1259 printk(KERN_INFO "sg_cmd_done: device detached\n");
1260 return;
1261 }
1262
1263
1264 SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1265 sdp->disk->disk_name, srp->header.pack_id, result));
1266 srp->header.resid = resid;
1267 ms = jiffies_to_msecs(jiffies);
1268 srp->header.duration = (ms > srp->header.duration) ?
1269 (ms - srp->header.duration) : 0;
1270 if (0 != result) {
1271 struct scsi_sense_hdr sshdr;
1272
1273 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1274 srp->header.status = 0xff & result;
1275 srp->header.masked_status = status_byte(result);
1276 srp->header.msg_status = msg_byte(result);
1277 srp->header.host_status = host_byte(result);
1278 srp->header.driver_status = driver_byte(result);
1279 if ((sdp->sgdebug > 0) &&
1280 ((CHECK_CONDITION == srp->header.masked_status) ||
1281 (COMMAND_TERMINATED == srp->header.masked_status)))
1282 __scsi_print_sense("sg_cmd_done", sense,
1283 SCSI_SENSE_BUFFERSIZE);
1284
1285 /* Following if statement is a patch supplied by Eric Youngdale */
1286 if (driver_byte(result) != 0
1287 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1288 && !scsi_sense_is_deferred(&sshdr)
1289 && sshdr.sense_key == UNIT_ATTENTION
1290 && sdp->device->removable) {
1291 /* Detected possible disc change. Set the bit - this */
1292 /* may be used if there are filesystems using this device */
1293 sdp->device->changed = 1;
1294 }
1295 }
1296 /* Rely on write phase to clean out srp status values, so no "else" */
1297
1298 if (sfp->closed) { /* whoops this fd already released, cleanup */
1299 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1300 sg_finish_rem_req(srp);
1301 srp = NULL;
1302 if (NULL == sfp->headrp) {
1303 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1304 if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */
1305 scsi_device_put(sdp->device);
1306 }
1307 sfp = NULL;
1308 }
1309 } else if (srp && srp->orphan) {
1310 if (sfp->keep_orphan)
1311 srp->sg_io_owned = 0;
1312 else {
1313 sg_finish_rem_req(srp);
1314 srp = NULL;
1315 }
1316 }
1317 if (sfp && srp) {
1318 /* Now wake up any sg_read() that is waiting for this packet. */
1319 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1320 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1321 srp->done = 1;
1322 wake_up_interruptible(&sfp->read_wait);
1323 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1324 }
1325 }
1326
1327 static struct file_operations sg_fops = {
1328 .owner = THIS_MODULE,
1329 .read = sg_read,
1330 .write = sg_write,
1331 .poll = sg_poll,
1332 .ioctl = sg_ioctl,
1333 #ifdef CONFIG_COMPAT
1334 .compat_ioctl = sg_compat_ioctl,
1335 #endif
1336 .open = sg_open,
1337 .mmap = sg_mmap,
1338 .release = sg_release,
1339 .fasync = sg_fasync,
1340 };
1341
1342 static struct class *sg_sysfs_class;
1343
1344 static int sg_sysfs_valid = 0;
1345
1346 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1347 {
1348 struct request_queue *q = scsidp->request_queue;
1349 Sg_device *sdp;
1350 unsigned long iflags;
1351 int error;
1352 u32 k;
1353
1354 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1355 if (!sdp) {
1356 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1357 return ERR_PTR(-ENOMEM);
1358 }
1359 error = -ENOMEM;
1360 if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1361 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1362 goto out;
1363 }
1364
1365 write_lock_irqsave(&sg_index_lock, iflags);
1366 error = idr_get_new(&sg_index_idr, sdp, &k);
1367 write_unlock_irqrestore(&sg_index_lock, iflags);
1368
1369 if (error) {
1370 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1371 error);
1372 goto out;
1373 }
1374
1375 if (unlikely(k >= SG_MAX_DEVS))
1376 goto overflow;
1377
1378 SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1379 sprintf(disk->disk_name, "sg%d", k);
1380 disk->first_minor = k;
1381 sdp->disk = disk;
1382 sdp->device = scsidp;
1383 init_waitqueue_head(&sdp->o_excl_wait);
1384 sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1385 sdp->index = k;
1386
1387 error = 0;
1388 out:
1389 if (error) {
1390 kfree(sdp);
1391 return ERR_PTR(error);
1392 }
1393 return sdp;
1394
1395 overflow:
1396 sdev_printk(KERN_WARNING, scsidp,
1397 "Unable to attach sg device type=%d, minor "
1398 "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1399 error = -ENODEV;
1400 goto out;
1401 }
1402
1403 static int
1404 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1405 {
1406 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1407 struct gendisk *disk;
1408 Sg_device *sdp = NULL;
1409 struct cdev * cdev = NULL;
1410 int error;
1411 unsigned long iflags;
1412
1413 disk = alloc_disk(1);
1414 if (!disk) {
1415 printk(KERN_WARNING "alloc_disk failed\n");
1416 return -ENOMEM;
1417 }
1418 disk->major = SCSI_GENERIC_MAJOR;
1419
1420 error = -ENOMEM;
1421 cdev = cdev_alloc();
1422 if (!cdev) {
1423 printk(KERN_WARNING "cdev_alloc failed\n");
1424 goto out;
1425 }
1426 cdev->owner = THIS_MODULE;
1427 cdev->ops = &sg_fops;
1428
1429 sdp = sg_alloc(disk, scsidp);
1430 if (IS_ERR(sdp)) {
1431 printk(KERN_WARNING "sg_alloc failed\n");
1432 error = PTR_ERR(sdp);
1433 goto out;
1434 }
1435
1436 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1437 if (error)
1438 goto cdev_add_err;
1439
1440 sdp->cdev = cdev;
1441 if (sg_sysfs_valid) {
1442 struct device *sg_class_member;
1443
1444 sg_class_member = device_create_drvdata(sg_sysfs_class,
1445 cl_dev->parent,
1446 MKDEV(SCSI_GENERIC_MAJOR,
1447 sdp->index),
1448 sdp,
1449 "%s", disk->disk_name);
1450 if (IS_ERR(sg_class_member)) {
1451 printk(KERN_ERR "sg_add: "
1452 "device_create failed\n");
1453 error = PTR_ERR(sg_class_member);
1454 goto cdev_add_err;
1455 }
1456 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1457 &sg_class_member->kobj, "generic");
1458 if (error)
1459 printk(KERN_ERR "sg_add: unable to make symlink "
1460 "'generic' back to sg%d\n", sdp->index);
1461 } else
1462 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1463
1464 sdev_printk(KERN_NOTICE, scsidp,
1465 "Attached scsi generic sg%d type %d\n", sdp->index,
1466 scsidp->type);
1467
1468 dev_set_drvdata(cl_dev, sdp);
1469
1470 return 0;
1471
1472 cdev_add_err:
1473 write_lock_irqsave(&sg_index_lock, iflags);
1474 idr_remove(&sg_index_idr, sdp->index);
1475 write_unlock_irqrestore(&sg_index_lock, iflags);
1476 kfree(sdp);
1477
1478 out:
1479 put_disk(disk);
1480 if (cdev)
1481 cdev_del(cdev);
1482 return error;
1483 }
1484
1485 static void
1486 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1487 {
1488 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1489 Sg_device *sdp = dev_get_drvdata(cl_dev);
1490 unsigned long iflags;
1491 Sg_fd *sfp;
1492 Sg_fd *tsfp;
1493 Sg_request *srp;
1494 Sg_request *tsrp;
1495 int delay;
1496
1497 if (!sdp)
1498 return;
1499
1500 delay = 0;
1501 write_lock_irqsave(&sg_index_lock, iflags);
1502 if (sdp->headfp) {
1503 sdp->detached = 1;
1504 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1505 tsfp = sfp->nextfp;
1506 for (srp = sfp->headrp; srp; srp = tsrp) {
1507 tsrp = srp->nextrp;
1508 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1509 sg_finish_rem_req(srp);
1510 }
1511 if (sfp->closed) {
1512 scsi_device_put(sdp->device);
1513 __sg_remove_sfp(sdp, sfp);
1514 } else {
1515 delay = 1;
1516 wake_up_interruptible(&sfp->read_wait);
1517 kill_fasync(&sfp->async_qp, SIGPOLL,
1518 POLL_HUP);
1519 }
1520 }
1521 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1522 if (NULL == sdp->headfp) {
1523 idr_remove(&sg_index_idr, sdp->index);
1524 }
1525 } else { /* nothing active, simple case */
1526 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1527 idr_remove(&sg_index_idr, sdp->index);
1528 }
1529 write_unlock_irqrestore(&sg_index_lock, iflags);
1530
1531 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1532 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1533 cdev_del(sdp->cdev);
1534 sdp->cdev = NULL;
1535 put_disk(sdp->disk);
1536 sdp->disk = NULL;
1537 if (NULL == sdp->headfp)
1538 kfree(sdp);
1539
1540 if (delay)
1541 msleep(10); /* dirty detach so delay device destruction */
1542 }
1543
1544 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1545 module_param_named(def_reserved_size, def_reserved_size, int,
1546 S_IRUGO | S_IWUSR);
1547 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1548
1549 MODULE_AUTHOR("Douglas Gilbert");
1550 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1551 MODULE_LICENSE("GPL");
1552 MODULE_VERSION(SG_VERSION_STR);
1553 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1554
1555 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1556 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1557 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1558 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1559
1560 static int __init
1561 init_sg(void)
1562 {
1563 int rc;
1564
1565 if (scatter_elem_sz < PAGE_SIZE) {
1566 scatter_elem_sz = PAGE_SIZE;
1567 scatter_elem_sz_prev = scatter_elem_sz;
1568 }
1569 if (def_reserved_size >= 0)
1570 sg_big_buff = def_reserved_size;
1571 else
1572 def_reserved_size = sg_big_buff;
1573
1574 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1575 SG_MAX_DEVS, "sg");
1576 if (rc)
1577 return rc;
1578 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1579 if ( IS_ERR(sg_sysfs_class) ) {
1580 rc = PTR_ERR(sg_sysfs_class);
1581 goto err_out;
1582 }
1583 sg_sysfs_valid = 1;
1584 rc = scsi_register_interface(&sg_interface);
1585 if (0 == rc) {
1586 #ifdef CONFIG_SCSI_PROC_FS
1587 sg_proc_init();
1588 #endif /* CONFIG_SCSI_PROC_FS */
1589 return 0;
1590 }
1591 class_destroy(sg_sysfs_class);
1592 err_out:
1593 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1594 return rc;
1595 }
1596
1597 static void __exit
1598 exit_sg(void)
1599 {
1600 #ifdef CONFIG_SCSI_PROC_FS
1601 sg_proc_cleanup();
1602 #endif /* CONFIG_SCSI_PROC_FS */
1603 scsi_unregister_interface(&sg_interface);
1604 class_destroy(sg_sysfs_class);
1605 sg_sysfs_valid = 0;
1606 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1607 SG_MAX_DEVS);
1608 idr_destroy(&sg_index_idr);
1609 }
1610
1611 static int
1612 sg_start_req(Sg_request * srp)
1613 {
1614 int res;
1615 Sg_fd *sfp = srp->parentfp;
1616 sg_io_hdr_t *hp = &srp->header;
1617 int dxfer_len = (int) hp->dxfer_len;
1618 int dxfer_dir = hp->dxfer_direction;
1619 Sg_scatter_hold *req_schp = &srp->data;
1620 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1621
1622 SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1623 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1624 return 0;
1625 if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1626 (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1627 (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1628 res = sg_build_direct(srp, sfp, dxfer_len);
1629 if (res <= 0) /* -ve -> error, 0 -> done, 1 -> try indirect */
1630 return res;
1631 }
1632 if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1633 sg_link_reserve(sfp, srp, dxfer_len);
1634 else {
1635 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1636 if (res) {
1637 sg_remove_scat(req_schp);
1638 return res;
1639 }
1640 }
1641 return 0;
1642 }
1643
1644 static void
1645 sg_finish_rem_req(Sg_request * srp)
1646 {
1647 Sg_fd *sfp = srp->parentfp;
1648 Sg_scatter_hold *req_schp = &srp->data;
1649
1650 SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1651 if (srp->res_used)
1652 sg_unlink_reserve(sfp, srp);
1653 else
1654 sg_remove_scat(req_schp);
1655 sg_remove_request(sfp, srp);
1656 }
1657
1658 static int
1659 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1660 {
1661 int sg_bufflen = tablesize * sizeof(struct scatterlist);
1662 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1663
1664 /*
1665 * TODO: test without low_dma, we should not need it since
1666 * the block layer will bounce the buffer for us
1667 *
1668 * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1669 */
1670 if (sfp->low_dma)
1671 gfp_flags |= GFP_DMA;
1672 schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1673 if (!schp->buffer)
1674 return -ENOMEM;
1675 sg_init_table(schp->buffer, tablesize);
1676 schp->sglist_len = sg_bufflen;
1677 return tablesize; /* number of scat_gath elements allocated */
1678 }
1679
1680 #ifdef SG_ALLOW_DIO_CODE
1681 /* vvvvvvvv following code borrowed from st driver's direct IO vvvvvvvvv */
1682 /* TODO: hopefully we can use the generic block layer code */
1683
1684 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1685 - mapping of all pages not successful
1686 (i.e., either completely successful or fails)
1687 */
1688 static int
1689 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1690 unsigned long uaddr, size_t count, int rw)
1691 {
1692 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1693 unsigned long start = uaddr >> PAGE_SHIFT;
1694 const int nr_pages = end - start;
1695 int res, i, j;
1696 struct page **pages;
1697
1698 /* User attempted Overflow! */
1699 if ((uaddr + count) < uaddr)
1700 return -EINVAL;
1701
1702 /* Too big */
1703 if (nr_pages > max_pages)
1704 return -ENOMEM;
1705
1706 /* Hmm? */
1707 if (count == 0)
1708 return 0;
1709
1710 if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1711 return -ENOMEM;
1712
1713 /* Try to fault in all of the necessary pages */
1714 down_read(&current->mm->mmap_sem);
1715 /* rw==READ means read from drive, write into memory area */
1716 res = get_user_pages(
1717 current,
1718 current->mm,
1719 uaddr,
1720 nr_pages,
1721 rw == READ,
1722 0, /* don't force */
1723 pages,
1724 NULL);
1725 up_read(&current->mm->mmap_sem);
1726
1727 /* Errors and no page mapped should return here */
1728 if (res < nr_pages)
1729 goto out_unmap;
1730
1731 for (i=0; i < nr_pages; i++) {
1732 /* FIXME: flush superflous for rw==READ,
1733 * probably wrong function for rw==WRITE
1734 */
1735 flush_dcache_page(pages[i]);
1736 /* ?? Is locking needed? I don't think so */
1737 /* if (TestSetPageLocked(pages[i]))
1738 goto out_unlock; */
1739 }
1740
1741 sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
1742 if (nr_pages > 1) {
1743 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1744 count -= sgl[0].length;
1745 for (i=1; i < nr_pages ; i++)
1746 sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
1747 }
1748 else {
1749 sgl[0].length = count;
1750 }
1751
1752 kfree(pages);
1753 return nr_pages;
1754
1755 out_unmap:
1756 if (res > 0) {
1757 for (j=0; j < res; j++)
1758 page_cache_release(pages[j]);
1759 res = 0;
1760 }
1761 kfree(pages);
1762 return res;
1763 }
1764
1765
1766 /* And unmap them... */
1767 static int
1768 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1769 int dirtied)
1770 {
1771 int i;
1772
1773 for (i=0; i < nr_pages; i++) {
1774 struct page *page = sg_page(&sgl[i]);
1775
1776 if (dirtied)
1777 SetPageDirty(page);
1778 /* unlock_page(page); */
1779 /* FIXME: cache flush missing for rw==READ
1780 * FIXME: call the correct reference counting function
1781 */
1782 page_cache_release(page);
1783 }
1784
1785 return 0;
1786 }
1787
1788 /* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */
1789 #endif
1790
1791
1792 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1793 static int
1794 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1795 {
1796 #ifdef SG_ALLOW_DIO_CODE
1797 sg_io_hdr_t *hp = &srp->header;
1798 Sg_scatter_hold *schp = &srp->data;
1799 int sg_tablesize = sfp->parentdp->sg_tablesize;
1800 int mx_sc_elems, res;
1801 struct scsi_device *sdev = sfp->parentdp->device;
1802
1803 if (((unsigned long)hp->dxferp &
1804 queue_dma_alignment(sdev->request_queue)) != 0)
1805 return 1;
1806
1807 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1808 if (mx_sc_elems <= 0) {
1809 return 1;
1810 }
1811 res = st_map_user_pages(schp->buffer, mx_sc_elems,
1812 (unsigned long)hp->dxferp, dxfer_len,
1813 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1814 if (res <= 0) {
1815 sg_remove_scat(schp);
1816 return 1;
1817 }
1818 schp->k_use_sg = res;
1819 schp->dio_in_use = 1;
1820 hp->info |= SG_INFO_DIRECT_IO;
1821 return 0;
1822 #else
1823 return 1;
1824 #endif
1825 }
1826
1827 static int
1828 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1829 {
1830 struct scatterlist *sg;
1831 int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1832 int sg_tablesize = sfp->parentdp->sg_tablesize;
1833 int blk_size = buff_size;
1834 struct page *p = NULL;
1835
1836 if (blk_size < 0)
1837 return -EFAULT;
1838 if (0 == blk_size)
1839 ++blk_size; /* don't know why */
1840 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1841 blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1842 SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1843 buff_size, blk_size));
1844
1845 /* N.B. ret_sz carried into this block ... */
1846 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1847 if (mx_sc_elems < 0)
1848 return mx_sc_elems; /* most likely -ENOMEM */
1849
1850 num = scatter_elem_sz;
1851 if (unlikely(num != scatter_elem_sz_prev)) {
1852 if (num < PAGE_SIZE) {
1853 scatter_elem_sz = PAGE_SIZE;
1854 scatter_elem_sz_prev = PAGE_SIZE;
1855 } else
1856 scatter_elem_sz_prev = num;
1857 }
1858 for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1859 (rem_sz > 0) && (k < mx_sc_elems);
1860 ++k, rem_sz -= ret_sz, sg = sg_next(sg)) {
1861
1862 num = (rem_sz > scatter_elem_sz_prev) ?
1863 scatter_elem_sz_prev : rem_sz;
1864 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1865 if (!p)
1866 return -ENOMEM;
1867
1868 if (num == scatter_elem_sz_prev) {
1869 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1870 scatter_elem_sz = ret_sz;
1871 scatter_elem_sz_prev = ret_sz;
1872 }
1873 }
1874 sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
1875
1876 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1877 "ret_sz=%d\n", k, num, ret_sz));
1878 } /* end of for loop */
1879
1880 schp->k_use_sg = k;
1881 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1882 "rem_sz=%d\n", k, rem_sz));
1883
1884 schp->bufflen = blk_size;
1885 if (rem_sz > 0) /* must have failed */
1886 return -ENOMEM;
1887
1888 return 0;
1889 }
1890
1891 static int
1892 sg_write_xfer(Sg_request * srp)
1893 {
1894 sg_io_hdr_t *hp = &srp->header;
1895 Sg_scatter_hold *schp = &srp->data;
1896 struct scatterlist *sg = schp->buffer;
1897 int num_xfer = 0;
1898 int j, k, onum, usglen, ksglen, res;
1899 int iovec_count = (int) hp->iovec_count;
1900 int dxfer_dir = hp->dxfer_direction;
1901 unsigned char *p;
1902 unsigned char __user *up;
1903 int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1904
1905 if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1906 (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1907 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1908 if (schp->bufflen < num_xfer)
1909 num_xfer = schp->bufflen;
1910 }
1911 if ((num_xfer <= 0) || (schp->dio_in_use) ||
1912 (new_interface
1913 && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1914 return 0;
1915
1916 SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1917 num_xfer, iovec_count, schp->k_use_sg));
1918 if (iovec_count) {
1919 onum = iovec_count;
1920 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1921 return -EFAULT;
1922 } else
1923 onum = 1;
1924
1925 ksglen = sg->length;
1926 p = page_address(sg_page(sg));
1927 for (j = 0, k = 0; j < onum; ++j) {
1928 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1929 if (res)
1930 return res;
1931
1932 for (; p; sg = sg_next(sg), ksglen = sg->length,
1933 p = page_address(sg_page(sg))) {
1934 if (usglen <= 0)
1935 break;
1936 if (ksglen > usglen) {
1937 if (usglen >= num_xfer) {
1938 if (__copy_from_user(p, up, num_xfer))
1939 return -EFAULT;
1940 return 0;
1941 }
1942 if (__copy_from_user(p, up, usglen))
1943 return -EFAULT;
1944 p += usglen;
1945 ksglen -= usglen;
1946 break;
1947 } else {
1948 if (ksglen >= num_xfer) {
1949 if (__copy_from_user(p, up, num_xfer))
1950 return -EFAULT;
1951 return 0;
1952 }
1953 if (__copy_from_user(p, up, ksglen))
1954 return -EFAULT;
1955 up += ksglen;
1956 usglen -= ksglen;
1957 }
1958 ++k;
1959 if (k >= schp->k_use_sg)
1960 return 0;
1961 }
1962 }
1963
1964 return 0;
1965 }
1966
1967 static int
1968 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1969 int wr_xf, int *countp, unsigned char __user **up)
1970 {
1971 int num_xfer = (int) hp->dxfer_len;
1972 unsigned char __user *p = hp->dxferp;
1973 int count;
1974
1975 if (0 == sg_num) {
1976 if (wr_xf && ('\0' == hp->interface_id))
1977 count = (int) hp->flags; /* holds "old" input_size */
1978 else
1979 count = num_xfer;
1980 } else {
1981 sg_iovec_t iovec;
1982 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1983 return -EFAULT;
1984 p = iovec.iov_base;
1985 count = (int) iovec.iov_len;
1986 }
1987 if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1988 return -EFAULT;
1989 if (up)
1990 *up = p;
1991 if (countp)
1992 *countp = count;
1993 return 0;
1994 }
1995
1996 static void
1997 sg_remove_scat(Sg_scatter_hold * schp)
1998 {
1999 SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2000 if (schp->buffer && (schp->sglist_len > 0)) {
2001 struct scatterlist *sg = schp->buffer;
2002
2003 if (schp->dio_in_use) {
2004 #ifdef SG_ALLOW_DIO_CODE
2005 st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2006 #endif
2007 } else {
2008 int k;
2009
2010 for (k = 0; (k < schp->k_use_sg) && sg_page(sg);
2011 ++k, sg = sg_next(sg)) {
2012 SCSI_LOG_TIMEOUT(5, printk(
2013 "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2014 k, sg_page(sg), sg->length));
2015 sg_page_free(sg_page(sg), sg->length);
2016 }
2017 }
2018 kfree(schp->buffer);
2019 }
2020 memset(schp, 0, sizeof (*schp));
2021 }
2022
2023 static int
2024 sg_read_xfer(Sg_request * srp)
2025 {
2026 sg_io_hdr_t *hp = &srp->header;
2027 Sg_scatter_hold *schp = &srp->data;
2028 struct scatterlist *sg = schp->buffer;
2029 int num_xfer = 0;
2030 int j, k, onum, usglen, ksglen, res;
2031 int iovec_count = (int) hp->iovec_count;
2032 int dxfer_dir = hp->dxfer_direction;
2033 unsigned char *p;
2034 unsigned char __user *up;
2035 int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2036
2037 if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2038 || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2039 num_xfer = hp->dxfer_len;
2040 if (schp->bufflen < num_xfer)
2041 num_xfer = schp->bufflen;
2042 }
2043 if ((num_xfer <= 0) || (schp->dio_in_use) ||
2044 (new_interface
2045 && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2046 return 0;
2047
2048 SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2049 num_xfer, iovec_count, schp->k_use_sg));
2050 if (iovec_count) {
2051 onum = iovec_count;
2052 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2053 return -EFAULT;
2054 } else
2055 onum = 1;
2056
2057 p = page_address(sg_page(sg));
2058 ksglen = sg->length;
2059 for (j = 0, k = 0; j < onum; ++j) {
2060 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2061 if (res)
2062 return res;
2063
2064 for (; p; sg = sg_next(sg), ksglen = sg->length,
2065 p = page_address(sg_page(sg))) {
2066 if (usglen <= 0)
2067 break;
2068 if (ksglen > usglen) {
2069 if (usglen >= num_xfer) {
2070 if (__copy_to_user(up, p, num_xfer))
2071 return -EFAULT;
2072 return 0;
2073 }
2074 if (__copy_to_user(up, p, usglen))
2075 return -EFAULT;
2076 p += usglen;
2077 ksglen -= usglen;
2078 break;
2079 } else {
2080 if (ksglen >= num_xfer) {
2081 if (__copy_to_user(up, p, num_xfer))
2082 return -EFAULT;
2083 return 0;
2084 }
2085 if (__copy_to_user(up, p, ksglen))
2086 return -EFAULT;
2087 up += ksglen;
2088 usglen -= ksglen;
2089 }
2090 ++k;
2091 if (k >= schp->k_use_sg)
2092 return 0;
2093 }
2094 }
2095
2096 return 0;
2097 }
2098
2099 static int
2100 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2101 {
2102 Sg_scatter_hold *schp = &srp->data;
2103 struct scatterlist *sg = schp->buffer;
2104 int k, num;
2105
2106 SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2107 num_read_xfer));
2108 if ((!outp) || (num_read_xfer <= 0))
2109 return 0;
2110
2111 for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) {
2112 num = sg->length;
2113 if (num > num_read_xfer) {
2114 if (__copy_to_user(outp, page_address(sg_page(sg)),
2115 num_read_xfer))
2116 return -EFAULT;
2117 break;
2118 } else {
2119 if (__copy_to_user(outp, page_address(sg_page(sg)),
2120 num))
2121 return -EFAULT;
2122 num_read_xfer -= num;
2123 if (num_read_xfer <= 0)
2124 break;
2125 outp += num;
2126 }
2127 }
2128
2129 return 0;
2130 }
2131
2132 static void
2133 sg_build_reserve(Sg_fd * sfp, int req_size)
2134 {
2135 Sg_scatter_hold *schp = &sfp->reserve;
2136
2137 SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2138 do {
2139 if (req_size < PAGE_SIZE)
2140 req_size = PAGE_SIZE;
2141 if (0 == sg_build_indirect(schp, sfp, req_size))
2142 return;
2143 else
2144 sg_remove_scat(schp);
2145 req_size >>= 1; /* divide by 2 */
2146 } while (req_size > (PAGE_SIZE / 2));
2147 }
2148
2149 static void
2150 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2151 {
2152 Sg_scatter_hold *req_schp = &srp->data;
2153 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2154 struct scatterlist *sg = rsv_schp->buffer;
2155 int k, num, rem;
2156
2157 srp->res_used = 1;
2158 SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2159 rem = size;
2160
2161 for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) {
2162 num = sg->length;
2163 if (rem <= num) {
2164 sfp->save_scat_len = num;
2165 sg->length = rem;
2166 req_schp->k_use_sg = k + 1;
2167 req_schp->sglist_len = rsv_schp->sglist_len;
2168 req_schp->buffer = rsv_schp->buffer;
2169
2170 req_schp->bufflen = size;
2171 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2172 break;
2173 } else
2174 rem -= num;
2175 }
2176
2177 if (k >= rsv_schp->k_use_sg)
2178 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2179 }
2180
2181 static void
2182 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2183 {
2184 Sg_scatter_hold *req_schp = &srp->data;
2185 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2186
2187 SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2188 (int) req_schp->k_use_sg));
2189 if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2190 struct scatterlist *sg = rsv_schp->buffer;
2191
2192 if (sfp->save_scat_len > 0)
2193 (sg + (req_schp->k_use_sg - 1))->length =
2194 (unsigned) sfp->save_scat_len;
2195 else
2196 SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2197 }
2198 req_schp->k_use_sg = 0;
2199 req_schp->bufflen = 0;
2200 req_schp->buffer = NULL;
2201 req_schp->sglist_len = 0;
2202 sfp->save_scat_len = 0;
2203 srp->res_used = 0;
2204 }
2205
2206 static Sg_request *
2207 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2208 {
2209 Sg_request *resp;
2210 unsigned long iflags;
2211
2212 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2213 for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2214 /* look for requests that are ready + not SG_IO owned */
2215 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2216 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2217 resp->done = 2; /* guard against other readers */
2218 break;
2219 }
2220 }
2221 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2222 return resp;
2223 }
2224
2225 #ifdef CONFIG_SCSI_PROC_FS
2226 static Sg_request *
2227 sg_get_nth_request(Sg_fd * sfp, int nth)
2228 {
2229 Sg_request *resp;
2230 unsigned long iflags;
2231 int k;
2232
2233 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2234 for (k = 0, resp = sfp->headrp; resp && (k < nth);
2235 ++k, resp = resp->nextrp) ;
2236 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2237 return resp;
2238 }
2239 #endif
2240
2241 /* always adds to end of list */
2242 static Sg_request *
2243 sg_add_request(Sg_fd * sfp)
2244 {
2245 int k;
2246 unsigned long iflags;
2247 Sg_request *resp;
2248 Sg_request *rp = sfp->req_arr;
2249
2250 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2251 resp = sfp->headrp;
2252 if (!resp) {
2253 memset(rp, 0, sizeof (Sg_request));
2254 rp->parentfp = sfp;
2255 resp = rp;
2256 sfp->headrp = resp;
2257 } else {
2258 if (0 == sfp->cmd_q)
2259 resp = NULL; /* command queuing disallowed */
2260 else {
2261 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2262 if (!rp->parentfp)
2263 break;
2264 }
2265 if (k < SG_MAX_QUEUE) {
2266 memset(rp, 0, sizeof (Sg_request));
2267 rp->parentfp = sfp;
2268 while (resp->nextrp)
2269 resp = resp->nextrp;
2270 resp->nextrp = rp;
2271 resp = rp;
2272 } else
2273 resp = NULL;
2274 }
2275 }
2276 if (resp) {
2277 resp->nextrp = NULL;
2278 resp->header.duration = jiffies_to_msecs(jiffies);
2279 }
2280 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2281 return resp;
2282 }
2283
2284 /* Return of 1 for found; 0 for not found */
2285 static int
2286 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2287 {
2288 Sg_request *prev_rp;
2289 Sg_request *rp;
2290 unsigned long iflags;
2291 int res = 0;
2292
2293 if ((!sfp) || (!srp) || (!sfp->headrp))
2294 return res;
2295 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2296 prev_rp = sfp->headrp;
2297 if (srp == prev_rp) {
2298 sfp->headrp = prev_rp->nextrp;
2299 prev_rp->parentfp = NULL;
2300 res = 1;
2301 } else {
2302 while ((rp = prev_rp->nextrp)) {
2303 if (srp == rp) {
2304 prev_rp->nextrp = rp->nextrp;
2305 rp->parentfp = NULL;
2306 res = 1;
2307 break;
2308 }
2309 prev_rp = rp;
2310 }
2311 }
2312 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2313 return res;
2314 }
2315
2316 #ifdef CONFIG_SCSI_PROC_FS
2317 static Sg_fd *
2318 sg_get_nth_sfp(Sg_device * sdp, int nth)
2319 {
2320 Sg_fd *resp;
2321 unsigned long iflags;
2322 int k;
2323
2324 read_lock_irqsave(&sg_index_lock, iflags);
2325 for (k = 0, resp = sdp->headfp; resp && (k < nth);
2326 ++k, resp = resp->nextfp) ;
2327 read_unlock_irqrestore(&sg_index_lock, iflags);
2328 return resp;
2329 }
2330 #endif
2331
2332 static Sg_fd *
2333 sg_add_sfp(Sg_device * sdp, int dev)
2334 {
2335 Sg_fd *sfp;
2336 unsigned long iflags;
2337 int bufflen;
2338
2339 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2340 if (!sfp)
2341 return NULL;
2342
2343 init_waitqueue_head(&sfp->read_wait);
2344 rwlock_init(&sfp->rq_list_lock);
2345
2346 sfp->timeout = SG_DEFAULT_TIMEOUT;
2347 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2348 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2349 sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2350 sdp->device->host->unchecked_isa_dma : 1;
2351 sfp->cmd_q = SG_DEF_COMMAND_Q;
2352 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2353 sfp->parentdp = sdp;
2354 write_lock_irqsave(&sg_index_lock, iflags);
2355 if (!sdp->headfp)
2356 sdp->headfp = sfp;
2357 else { /* add to tail of existing list */
2358 Sg_fd *pfp = sdp->headfp;
2359 while (pfp->nextfp)
2360 pfp = pfp->nextfp;
2361 pfp->nextfp = sfp;
2362 }
2363 write_unlock_irqrestore(&sg_index_lock, iflags);
2364 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2365 if (unlikely(sg_big_buff != def_reserved_size))
2366 sg_big_buff = def_reserved_size;
2367
2368 bufflen = min_t(int, sg_big_buff,
2369 sdp->device->request_queue->max_sectors * 512);
2370 sg_build_reserve(sfp, bufflen);
2371 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2372 sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2373 return sfp;
2374 }
2375
2376 static void
2377 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2378 {
2379 Sg_fd *fp;
2380 Sg_fd *prev_fp;
2381
2382 prev_fp = sdp->headfp;
2383 if (sfp == prev_fp)
2384 sdp->headfp = prev_fp->nextfp;
2385 else {
2386 while ((fp = prev_fp->nextfp)) {
2387 if (sfp == fp) {
2388 prev_fp->nextfp = fp->nextfp;
2389 break;
2390 }
2391 prev_fp = fp;
2392 }
2393 }
2394 if (sfp->reserve.bufflen > 0) {
2395 SCSI_LOG_TIMEOUT(6,
2396 printk("__sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2397 (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2398 sg_remove_scat(&sfp->reserve);
2399 }
2400 sfp->parentdp = NULL;
2401 SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp: sfp=0x%p\n", sfp));
2402 kfree(sfp);
2403 }
2404
2405 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2406 static int
2407 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2408 {
2409 Sg_request *srp;
2410 Sg_request *tsrp;
2411 int dirty = 0;
2412 int res = 0;
2413
2414 for (srp = sfp->headrp; srp; srp = tsrp) {
2415 tsrp = srp->nextrp;
2416 if (sg_srp_done(srp, sfp))
2417 sg_finish_rem_req(srp);
2418 else
2419 ++dirty;
2420 }
2421 if (0 == dirty) {
2422 unsigned long iflags;
2423
2424 write_lock_irqsave(&sg_index_lock, iflags);
2425 __sg_remove_sfp(sdp, sfp);
2426 if (sdp->detached && (NULL == sdp->headfp)) {
2427 idr_remove(&sg_index_idr, sdp->index);
2428 kfree(sdp);
2429 res = 1;
2430 }
2431 write_unlock_irqrestore(&sg_index_lock, iflags);
2432 } else {
2433 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2434 /* only bump the access_count if we actually succeeded in
2435 * throwing another counter on the host module */
2436 scsi_device_get(sdp->device); /* XXX: retval ignored? */
2437 sfp->closed = 1; /* flag dirty state on this fd */
2438 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2439 dirty));
2440 }
2441 return res;
2442 }
2443
2444 static int
2445 sg_res_in_use(Sg_fd * sfp)
2446 {
2447 const Sg_request *srp;
2448 unsigned long iflags;
2449
2450 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2451 for (srp = sfp->headrp; srp; srp = srp->nextrp)
2452 if (srp->res_used)
2453 break;
2454 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2455 return srp ? 1 : 0;
2456 }
2457
2458 /* The size fetched (value output via retSzp) set when non-NULL return */
2459 static struct page *
2460 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2461 {
2462 struct page *resp = NULL;
2463 gfp_t page_mask;
2464 int order, a_size;
2465 int resSz;
2466
2467 if ((rqSz <= 0) || (NULL == retSzp))
2468 return resp;
2469
2470 if (lowDma)
2471 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2472 else
2473 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2474
2475 for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2476 order++, a_size <<= 1) ;
2477 resSz = a_size; /* rounded up if necessary */
2478 resp = alloc_pages(page_mask, order);
2479 while ((!resp) && order) {
2480 --order;
2481 a_size >>= 1; /* divide by 2, until PAGE_SIZE */
2482 resp = alloc_pages(page_mask, order); /* try half */
2483 resSz = a_size;
2484 }
2485 if (resp) {
2486 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2487 memset(page_address(resp), 0, resSz);
2488 *retSzp = resSz;
2489 }
2490 return resp;
2491 }
2492
2493 static void
2494 sg_page_free(struct page *page, int size)
2495 {
2496 int order, a_size;
2497
2498 if (!page)
2499 return;
2500 for (order = 0, a_size = PAGE_SIZE; a_size < size;
2501 order++, a_size <<= 1) ;
2502 __free_pages(page, order);
2503 }
2504
2505 #ifndef MAINTENANCE_IN_CMD
2506 #define MAINTENANCE_IN_CMD 0xa3
2507 #endif
2508
2509 #ifdef CONFIG_SCSI_PROC_FS
2510 static int
2511 sg_idr_max_id(int id, void *p, void *data)
2512 {
2513 int *k = data;
2514
2515 if (*k < id)
2516 *k = id;
2517
2518 return 0;
2519 }
2520
2521 static int
2522 sg_last_dev(void)
2523 {
2524 int k = -1;
2525 unsigned long iflags;
2526
2527 read_lock_irqsave(&sg_index_lock, iflags);
2528 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2529 read_unlock_irqrestore(&sg_index_lock, iflags);
2530 return k + 1; /* origin 1 */
2531 }
2532 #endif
2533
2534 static Sg_device *
2535 sg_get_dev(int dev)
2536 {
2537 Sg_device *sdp;
2538 unsigned long iflags;
2539
2540 read_lock_irqsave(&sg_index_lock, iflags);
2541 sdp = idr_find(&sg_index_idr, dev);
2542 read_unlock_irqrestore(&sg_index_lock, iflags);
2543
2544 return sdp;
2545 }
2546
2547 #ifdef CONFIG_SCSI_PROC_FS
2548
2549 static struct proc_dir_entry *sg_proc_sgp = NULL;
2550
2551 static char sg_proc_sg_dirname[] = "scsi/sg";
2552
2553 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2554
2555 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2556 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2557 size_t count, loff_t *off);
2558 static struct file_operations adio_fops = {
2559 /* .owner, .read and .llseek added in sg_proc_init() */
2560 .open = sg_proc_single_open_adio,
2561 .write = sg_proc_write_adio,
2562 .release = single_release,
2563 };
2564
2565 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2566 static ssize_t sg_proc_write_dressz(struct file *filp,
2567 const char __user *buffer, size_t count, loff_t *off);
2568 static struct file_operations dressz_fops = {
2569 .open = sg_proc_single_open_dressz,
2570 .write = sg_proc_write_dressz,
2571 .release = single_release,
2572 };
2573
2574 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2575 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2576 static struct file_operations version_fops = {
2577 .open = sg_proc_single_open_version,
2578 .release = single_release,
2579 };
2580
2581 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2582 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2583 static struct file_operations devhdr_fops = {
2584 .open = sg_proc_single_open_devhdr,
2585 .release = single_release,
2586 };
2587
2588 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2589 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2590 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2591 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2592 static void dev_seq_stop(struct seq_file *s, void *v);
2593 static struct file_operations dev_fops = {
2594 .open = sg_proc_open_dev,
2595 .release = seq_release,
2596 };
2597 static struct seq_operations dev_seq_ops = {
2598 .start = dev_seq_start,
2599 .next = dev_seq_next,
2600 .stop = dev_seq_stop,
2601 .show = sg_proc_seq_show_dev,
2602 };
2603
2604 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2605 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2606 static struct file_operations devstrs_fops = {
2607 .open = sg_proc_open_devstrs,
2608 .release = seq_release,
2609 };
2610 static struct seq_operations devstrs_seq_ops = {
2611 .start = dev_seq_start,
2612 .next = dev_seq_next,
2613 .stop = dev_seq_stop,
2614 .show = sg_proc_seq_show_devstrs,
2615 };
2616
2617 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2618 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2619 static struct file_operations debug_fops = {
2620 .open = sg_proc_open_debug,
2621 .release = seq_release,
2622 };
2623 static struct seq_operations debug_seq_ops = {
2624 .start = dev_seq_start,
2625 .next = dev_seq_next,
2626 .stop = dev_seq_stop,
2627 .show = sg_proc_seq_show_debug,
2628 };
2629
2630
2631 struct sg_proc_leaf {
2632 const char * name;
2633 struct file_operations * fops;
2634 };
2635
2636 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2637 {"allow_dio", &adio_fops},
2638 {"debug", &debug_fops},
2639 {"def_reserved_size", &dressz_fops},
2640 {"device_hdr", &devhdr_fops},
2641 {"devices", &dev_fops},
2642 {"device_strs", &devstrs_fops},
2643 {"version", &version_fops}
2644 };
2645
2646 static int
2647 sg_proc_init(void)
2648 {
2649 int k, mask;
2650 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2651 struct sg_proc_leaf * leaf;
2652
2653 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2654 if (!sg_proc_sgp)
2655 return 1;
2656 for (k = 0; k < num_leaves; ++k) {
2657 leaf = &sg_proc_leaf_arr[k];
2658 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2659 leaf->fops->owner = THIS_MODULE;
2660 leaf->fops->read = seq_read;
2661 leaf->fops->llseek = seq_lseek;
2662 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2663 }
2664 return 0;
2665 }
2666
2667 static void
2668 sg_proc_cleanup(void)
2669 {
2670 int k;
2671 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2672
2673 if (!sg_proc_sgp)
2674 return;
2675 for (k = 0; k < num_leaves; ++k)
2676 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2677 remove_proc_entry(sg_proc_sg_dirname, NULL);
2678 }
2679
2680
2681 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2682 {
2683 seq_printf(s, "%d\n", *((int *)s->private));
2684 return 0;
2685 }
2686
2687 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2688 {
2689 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2690 }
2691
2692 static ssize_t
2693 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2694 size_t count, loff_t *off)
2695 {
2696 int num;
2697 char buff[11];
2698
2699 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2700 return -EACCES;
2701 num = (count < 10) ? count : 10;
2702 if (copy_from_user(buff, buffer, num))
2703 return -EFAULT;
2704 buff[num] = '\0';
2705 sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2706 return count;
2707 }
2708
2709 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2710 {
2711 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2712 }
2713
2714 static ssize_t
2715 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2716 size_t count, loff_t *off)
2717 {
2718 int num;
2719 unsigned long k = ULONG_MAX;
2720 char buff[11];
2721
2722 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2723 return -EACCES;
2724 num = (count < 10) ? count : 10;
2725 if (copy_from_user(buff, buffer, num))
2726 return -EFAULT;
2727 buff[num] = '\0';
2728 k = simple_strtoul(buff, NULL, 10);
2729 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2730 sg_big_buff = k;
2731 return count;
2732 }
2733 return -ERANGE;
2734 }
2735
2736 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2737 {
2738 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2739 sg_version_date);
2740 return 0;
2741 }
2742
2743 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2744 {
2745 return single_open(file, sg_proc_seq_show_version, NULL);
2746 }
2747
2748 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2749 {
2750 seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2751 "online\n");
2752 return 0;
2753 }
2754
2755 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2756 {
2757 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2758 }
2759
2760 struct sg_proc_deviter {
2761 loff_t index;
2762 size_t max;
2763 };
2764
2765 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2766 {
2767 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2768
2769 s->private = it;
2770 if (! it)
2771 return NULL;
2772
2773 it->index = *pos;
2774 it->max = sg_last_dev();
2775 if (it->index >= it->max)
2776 return NULL;
2777 return it;
2778 }
2779
2780 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2781 {
2782 struct sg_proc_deviter * it = s->private;
2783
2784 *pos = ++it->index;
2785 return (it->index < it->max) ? it : NULL;
2786 }
2787
2788 static void dev_seq_stop(struct seq_file *s, void *v)
2789 {
2790 kfree(s->private);
2791 }
2792
2793 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2794 {
2795 return seq_open(file, &dev_seq_ops);
2796 }
2797
2798 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2799 {
2800 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2801 Sg_device *sdp;
2802 struct scsi_device *scsidp;
2803
2804 sdp = it ? sg_get_dev(it->index) : NULL;
2805 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2806 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2807 scsidp->host->host_no, scsidp->channel,
2808 scsidp->id, scsidp->lun, (int) scsidp->type,
2809 1,
2810 (int) scsidp->queue_depth,
2811 (int) scsidp->device_busy,
2812 (int) scsi_device_online(scsidp));
2813 else
2814 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2815 return 0;
2816 }
2817
2818 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2819 {
2820 return seq_open(file, &devstrs_seq_ops);
2821 }
2822
2823 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2824 {
2825 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2826 Sg_device *sdp;
2827 struct scsi_device *scsidp;
2828
2829 sdp = it ? sg_get_dev(it->index) : NULL;
2830 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2831 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2832 scsidp->vendor, scsidp->model, scsidp->rev);
2833 else
2834 seq_printf(s, "<no active device>\n");
2835 return 0;
2836 }
2837
2838 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2839 {
2840 int k, m, new_interface, blen, usg;
2841 Sg_request *srp;
2842 Sg_fd *fp;
2843 const sg_io_hdr_t *hp;
2844 const char * cp;
2845 unsigned int ms;
2846
2847 for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2848 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2849 "(res)sgat=%d low_dma=%d\n", k + 1,
2850 jiffies_to_msecs(fp->timeout),
2851 fp->reserve.bufflen,
2852 (int) fp->reserve.k_use_sg,
2853 (int) fp->low_dma);
2854 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2855 (int) fp->cmd_q, (int) fp->force_packid,
2856 (int) fp->keep_orphan, (int) fp->closed);
2857 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2858 hp = &srp->header;
2859 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2860 if (srp->res_used) {
2861 if (new_interface &&
2862 (SG_FLAG_MMAP_IO & hp->flags))
2863 cp = " mmap>> ";
2864 else
2865 cp = " rb>> ";
2866 } else {
2867 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2868 cp = " dio>> ";
2869 else
2870 cp = " ";
2871 }
2872 seq_printf(s, cp);
2873 blen = srp->data.bufflen;
2874 usg = srp->data.k_use_sg;
2875 seq_printf(s, srp->done ?
2876 ((1 == srp->done) ? "rcv:" : "fin:")
2877 : "act:");
2878 seq_printf(s, " id=%d blen=%d",
2879 srp->header.pack_id, blen);
2880 if (srp->done)
2881 seq_printf(s, " dur=%d", hp->duration);
2882 else {
2883 ms = jiffies_to_msecs(jiffies);
2884 seq_printf(s, " t_o/elap=%d/%d",
2885 (new_interface ? hp->timeout :
2886 jiffies_to_msecs(fp->timeout)),
2887 (ms > hp->duration ? ms - hp->duration : 0));
2888 }
2889 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2890 (int) srp->data.cmd_opcode);
2891 }
2892 if (0 == m)
2893 seq_printf(s, " No requests active\n");
2894 }
2895 }
2896
2897 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2898 {
2899 return seq_open(file, &debug_seq_ops);
2900 }
2901
2902 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2903 {
2904 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2905 Sg_device *sdp;
2906
2907 if (it && (0 == it->index)) {
2908 seq_printf(s, "max_active_device=%d(origin 1)\n",
2909 (int)it->max);
2910 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2911 }
2912 sdp = it ? sg_get_dev(it->index) : NULL;
2913 if (sdp) {
2914 struct scsi_device *scsidp = sdp->device;
2915
2916 if (NULL == scsidp) {
2917 seq_printf(s, "device %d detached ??\n",
2918 (int)it->index);
2919 return 0;
2920 }
2921
2922 if (sg_get_nth_sfp(sdp, 0)) {
2923 seq_printf(s, " >>> device=%s ",
2924 sdp->disk->disk_name);
2925 if (sdp->detached)
2926 seq_printf(s, "detached pending close ");
2927 else
2928 seq_printf
2929 (s, "scsi%d chan=%d id=%d lun=%d em=%d",
2930 scsidp->host->host_no,
2931 scsidp->channel, scsidp->id,
2932 scsidp->lun,
2933 scsidp->host->hostt->emulated);
2934 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2935 sdp->sg_tablesize, sdp->exclude);
2936 }
2937 sg_proc_debug_helper(s, sdp);
2938 }
2939 return 0;
2940 }
2941
2942 #endif /* CONFIG_SCSI_PROC_FS */
2943
2944 module_init(init_sg);
2945 module_exit(exit_sg);
Linux kernel - Deliverables
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