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Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[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 #include <linux/smp_lock.h>
53
54 #include "scsi.h"
55 #include <scsi/scsi_dbg.h>
56 #include <scsi/scsi_host.h>
57 #include <scsi/scsi_driver.h>
58 #include <scsi/scsi_ioctl.h>
59 #include <scsi/sg.h>
60
61 #include "scsi_logging.h"
62
63 #ifdef CONFIG_SCSI_PROC_FS
64 #include <linux/proc_fs.h>
65 static char *sg_version_date = "20061027";
66
67 static int sg_proc_init(void);
68 static void sg_proc_cleanup(void);
69 #endif
70
71 #define SG_ALLOW_DIO_DEF 0
72 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */
73
74 #define SG_MAX_DEVS 32768
75
76 /*
77 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
78 * Then when using 32 bit integers x * m may overflow during the calculation.
79 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
80 * calculates the same, but prevents the overflow when both m and d
81 * are "small" numbers (like HZ and USER_HZ).
82 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
83 * in 32 bits.
84 */
85 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
86
87 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
88
89 int sg_big_buff = SG_DEF_RESERVED_SIZE;
90 /* N.B. This variable is readable and writeable via
91 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
92 of this size (or less if there is not enough memory) will be reserved
93 for use by this file descriptor. [Deprecated usage: this variable is also
94 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
95 the kernel (i.e. it is not a module).] */
96 static int def_reserved_size = -1; /* picks up init parameter */
97 static int sg_allow_dio = SG_ALLOW_DIO_DEF;
98
99 static int scatter_elem_sz = SG_SCATTER_SZ;
100 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
101
102 #define SG_SECTOR_SZ 512
103 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
104
105 static int sg_add(struct device *, struct class_interface *);
106 static void sg_remove(struct device *, struct class_interface *);
107
108 static DEFINE_IDR(sg_index_idr);
109 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
110 file descriptor list for device */
111
112 static struct class_interface sg_interface = {
113 .add_dev = sg_add,
114 .remove_dev = sg_remove,
115 };
116
117 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
118 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
119 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
120 unsigned bufflen; /* Size of (aggregate) data buffer */
121 unsigned b_malloc_len; /* actual len malloc'ed in buffer */
122 struct scatterlist *buffer;/* scatter list */
123 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
124 unsigned char cmd_opcode; /* first byte of command */
125 } Sg_scatter_hold;
126
127 struct sg_device; /* forward declarations */
128 struct sg_fd;
129
130 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
131 struct sg_request *nextrp; /* NULL -> tail request (slist) */
132 struct sg_fd *parentfp; /* NULL -> not in use */
133 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
134 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
135 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
136 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
137 char orphan; /* 1 -> drop on sight, 0 -> normal */
138 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
139 volatile char done; /* 0->before bh, 1->before read, 2->read */
140 } Sg_request;
141
142 typedef struct sg_fd { /* holds the state of a file descriptor */
143 struct sg_fd *nextfp; /* NULL when last opened fd on this device */
144 struct sg_device *parentdp; /* owning device */
145 wait_queue_head_t read_wait; /* queue read until command done */
146 rwlock_t rq_list_lock; /* protect access to list in req_arr */
147 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
148 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
149 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
150 unsigned save_scat_len; /* original length of trunc. scat. element */
151 Sg_request *headrp; /* head of request slist, NULL->empty */
152 struct fasync_struct *async_qp; /* used by asynchronous notification */
153 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
154 char low_dma; /* as in parent but possibly overridden to 1 */
155 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
156 volatile char closed; /* 1 -> fd closed but request(s) outstanding */
157 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
158 char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
159 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
160 char mmap_called; /* 0 -> mmap() never called on this fd */
161 } Sg_fd;
162
163 typedef struct sg_device { /* holds the state of each scsi generic device */
164 struct scsi_device *device;
165 wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
166 int sg_tablesize; /* adapter's max scatter-gather table size */
167 u32 index; /* device index number */
168 Sg_fd *headfp; /* first open fd belonging to this device */
169 volatile char detached; /* 0->attached, 1->detached pending removal */
170 volatile char exclude; /* opened for exclusive access */
171 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
172 struct gendisk *disk;
173 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
174 } Sg_device;
175
176 static int sg_fasync(int fd, struct file *filp, int mode);
177 /* tasklet or soft irq callback */
178 static void sg_cmd_done(void *data, char *sense, int result, int resid);
179 static int sg_start_req(Sg_request * srp);
180 static void sg_finish_rem_req(Sg_request * srp);
181 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
182 static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp,
183 int tablesize);
184 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
185 Sg_request * srp);
186 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
187 const char __user *buf, size_t count, int blocking,
188 int read_only, Sg_request **o_srp);
189 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
190 unsigned char *cmnd, int timeout, int blocking);
191 static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
192 int wr_xf, int *countp, unsigned char __user **up);
193 static int sg_write_xfer(Sg_request * srp);
194 static int sg_read_xfer(Sg_request * srp);
195 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
196 static void sg_remove_scat(Sg_scatter_hold * schp);
197 static void sg_build_reserve(Sg_fd * sfp, int req_size);
198 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
199 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
200 static struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
201 static void sg_page_free(struct page *page, int size);
202 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
203 static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
204 static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
205 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
206 static Sg_request *sg_add_request(Sg_fd * sfp);
207 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
208 static int sg_res_in_use(Sg_fd * sfp);
209 static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
210 static Sg_device *sg_get_dev(int dev);
211 #ifdef CONFIG_SCSI_PROC_FS
212 static int sg_last_dev(void);
213 #endif
214
215 #define SZ_SG_HEADER sizeof(struct sg_header)
216 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
217 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
218 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
219
220 static int
221 sg_open(struct inode *inode, struct file *filp)
222 {
223 int dev = iminor(inode);
224 int flags = filp->f_flags;
225 struct request_queue *q;
226 Sg_device *sdp;
227 Sg_fd *sfp;
228 int res;
229 int retval;
230
231 lock_kernel();
232 nonseekable_open(inode, filp);
233 SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
234 sdp = sg_get_dev(dev);
235 if ((!sdp) || (!sdp->device)) {
236 unlock_kernel();
237 return -ENXIO;
238 }
239 if (sdp->detached) {
240 unlock_kernel();
241 return -ENODEV;
242 }
243
244 /* This driver's module count bumped by fops_get in <linux/fs.h> */
245 /* Prevent the device driver from vanishing while we sleep */
246 retval = scsi_device_get(sdp->device);
247 if (retval) {
248 unlock_kernel();
249 return retval;
250 }
251
252 if (!((flags & O_NONBLOCK) ||
253 scsi_block_when_processing_errors(sdp->device))) {
254 retval = -ENXIO;
255 /* we are in error recovery for this device */
256 goto error_out;
257 }
258
259 if (flags & O_EXCL) {
260 if (O_RDONLY == (flags & O_ACCMODE)) {
261 retval = -EPERM; /* Can't lock it with read only access */
262 goto error_out;
263 }
264 if (sdp->headfp && (flags & O_NONBLOCK)) {
265 retval = -EBUSY;
266 goto error_out;
267 }
268 res = 0;
269 __wait_event_interruptible(sdp->o_excl_wait,
270 ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
271 if (res) {
272 retval = res; /* -ERESTARTSYS because signal hit process */
273 goto error_out;
274 }
275 } else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */
276 if (flags & O_NONBLOCK) {
277 retval = -EBUSY;
278 goto error_out;
279 }
280 res = 0;
281 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
282 res);
283 if (res) {
284 retval = res; /* -ERESTARTSYS because signal hit process */
285 goto error_out;
286 }
287 }
288 if (sdp->detached) {
289 retval = -ENODEV;
290 goto error_out;
291 }
292 if (!sdp->headfp) { /* no existing opens on this device */
293 sdp->sgdebug = 0;
294 q = sdp->device->request_queue;
295 sdp->sg_tablesize = min(q->max_hw_segments,
296 q->max_phys_segments);
297 }
298 if ((sfp = sg_add_sfp(sdp, dev)))
299 filp->private_data = sfp;
300 else {
301 if (flags & O_EXCL)
302 sdp->exclude = 0; /* undo if error */
303 retval = -ENOMEM;
304 goto error_out;
305 }
306 unlock_kernel();
307 return 0;
308
309 error_out:
310 scsi_device_put(sdp->device);
311 unlock_kernel();
312 return retval;
313 }
314
315 /* Following function was formerly called 'sg_close' */
316 static int
317 sg_release(struct inode *inode, struct file *filp)
318 {
319 Sg_device *sdp;
320 Sg_fd *sfp;
321
322 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
323 return -ENXIO;
324 SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
325 sg_fasync(-1, filp, 0); /* remove filp from async notification list */
326 if (0 == sg_remove_sfp(sdp, sfp)) { /* Returns 1 when sdp gone */
327 if (!sdp->detached) {
328 scsi_device_put(sdp->device);
329 }
330 sdp->exclude = 0;
331 wake_up_interruptible(&sdp->o_excl_wait);
332 }
333 return 0;
334 }
335
336 static ssize_t
337 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
338 {
339 Sg_device *sdp;
340 Sg_fd *sfp;
341 Sg_request *srp;
342 int req_pack_id = -1;
343 sg_io_hdr_t *hp;
344 struct sg_header *old_hdr = NULL;
345 int retval = 0;
346
347 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
348 return -ENXIO;
349 SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
350 sdp->disk->disk_name, (int) count));
351
352 if (!access_ok(VERIFY_WRITE, buf, count))
353 return -EFAULT;
354 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
355 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
356 if (!old_hdr)
357 return -ENOMEM;
358 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
359 retval = -EFAULT;
360 goto free_old_hdr;
361 }
362 if (old_hdr->reply_len < 0) {
363 if (count >= SZ_SG_IO_HDR) {
364 sg_io_hdr_t *new_hdr;
365 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
366 if (!new_hdr) {
367 retval = -ENOMEM;
368 goto free_old_hdr;
369 }
370 retval =__copy_from_user
371 (new_hdr, buf, SZ_SG_IO_HDR);
372 req_pack_id = new_hdr->pack_id;
373 kfree(new_hdr);
374 if (retval) {
375 retval = -EFAULT;
376 goto free_old_hdr;
377 }
378 }
379 } else
380 req_pack_id = old_hdr->pack_id;
381 }
382 srp = sg_get_rq_mark(sfp, req_pack_id);
383 if (!srp) { /* now wait on packet to arrive */
384 if (sdp->detached) {
385 retval = -ENODEV;
386 goto free_old_hdr;
387 }
388 if (filp->f_flags & O_NONBLOCK) {
389 retval = -EAGAIN;
390 goto free_old_hdr;
391 }
392 while (1) {
393 retval = 0; /* following macro beats race condition */
394 __wait_event_interruptible(sfp->read_wait,
395 (sdp->detached ||
396 (srp = sg_get_rq_mark(sfp, req_pack_id))),
397 retval);
398 if (sdp->detached) {
399 retval = -ENODEV;
400 goto free_old_hdr;
401 }
402 if (0 == retval)
403 break;
404
405 /* -ERESTARTSYS as signal hit process */
406 goto free_old_hdr;
407 }
408 }
409 if (srp->header.interface_id != '\0') {
410 retval = sg_new_read(sfp, buf, count, srp);
411 goto free_old_hdr;
412 }
413
414 hp = &srp->header;
415 if (old_hdr == NULL) {
416 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
417 if (! old_hdr) {
418 retval = -ENOMEM;
419 goto free_old_hdr;
420 }
421 }
422 memset(old_hdr, 0, SZ_SG_HEADER);
423 old_hdr->reply_len = (int) hp->timeout;
424 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
425 old_hdr->pack_id = hp->pack_id;
426 old_hdr->twelve_byte =
427 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
428 old_hdr->target_status = hp->masked_status;
429 old_hdr->host_status = hp->host_status;
430 old_hdr->driver_status = hp->driver_status;
431 if ((CHECK_CONDITION & hp->masked_status) ||
432 (DRIVER_SENSE & hp->driver_status))
433 memcpy(old_hdr->sense_buffer, srp->sense_b,
434 sizeof (old_hdr->sense_buffer));
435 switch (hp->host_status) {
436 /* This setup of 'result' is for backward compatibility and is best
437 ignored by the user who should use target, host + driver status */
438 case DID_OK:
439 case DID_PASSTHROUGH:
440 case DID_SOFT_ERROR:
441 old_hdr->result = 0;
442 break;
443 case DID_NO_CONNECT:
444 case DID_BUS_BUSY:
445 case DID_TIME_OUT:
446 old_hdr->result = EBUSY;
447 break;
448 case DID_BAD_TARGET:
449 case DID_ABORT:
450 case DID_PARITY:
451 case DID_RESET:
452 case DID_BAD_INTR:
453 old_hdr->result = EIO;
454 break;
455 case DID_ERROR:
456 old_hdr->result = (srp->sense_b[0] == 0 &&
457 hp->masked_status == GOOD) ? 0 : EIO;
458 break;
459 default:
460 old_hdr->result = EIO;
461 break;
462 }
463
464 /* Now copy the result back to the user buffer. */
465 if (count >= SZ_SG_HEADER) {
466 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
467 retval = -EFAULT;
468 goto free_old_hdr;
469 }
470 buf += SZ_SG_HEADER;
471 if (count > old_hdr->reply_len)
472 count = old_hdr->reply_len;
473 if (count > SZ_SG_HEADER) {
474 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
475 retval = -EFAULT;
476 goto free_old_hdr;
477 }
478 }
479 } else
480 count = (old_hdr->result == 0) ? 0 : -EIO;
481 sg_finish_rem_req(srp);
482 retval = count;
483 free_old_hdr:
484 kfree(old_hdr);
485 return retval;
486 }
487
488 static ssize_t
489 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
490 {
491 sg_io_hdr_t *hp = &srp->header;
492 int err = 0;
493 int len;
494
495 if (count < SZ_SG_IO_HDR) {
496 err = -EINVAL;
497 goto err_out;
498 }
499 hp->sb_len_wr = 0;
500 if ((hp->mx_sb_len > 0) && hp->sbp) {
501 if ((CHECK_CONDITION & hp->masked_status) ||
502 (DRIVER_SENSE & hp->driver_status)) {
503 int sb_len = SCSI_SENSE_BUFFERSIZE;
504 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
505 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
506 len = (len > sb_len) ? sb_len : len;
507 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
508 err = -EFAULT;
509 goto err_out;
510 }
511 hp->sb_len_wr = len;
512 }
513 }
514 if (hp->masked_status || hp->host_status || hp->driver_status)
515 hp->info |= SG_INFO_CHECK;
516 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
517 err = -EFAULT;
518 goto err_out;
519 }
520 err = sg_read_xfer(srp);
521 err_out:
522 sg_finish_rem_req(srp);
523 return (0 == err) ? count : err;
524 }
525
526 static ssize_t
527 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
528 {
529 int mxsize, cmd_size, k;
530 int input_size, blocking;
531 unsigned char opcode;
532 Sg_device *sdp;
533 Sg_fd *sfp;
534 Sg_request *srp;
535 struct sg_header old_hdr;
536 sg_io_hdr_t *hp;
537 unsigned char cmnd[MAX_COMMAND_SIZE];
538
539 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
540 return -ENXIO;
541 SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
542 sdp->disk->disk_name, (int) count));
543 if (sdp->detached)
544 return -ENODEV;
545 if (!((filp->f_flags & O_NONBLOCK) ||
546 scsi_block_when_processing_errors(sdp->device)))
547 return -ENXIO;
548
549 if (!access_ok(VERIFY_READ, buf, count))
550 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
551 if (count < SZ_SG_HEADER)
552 return -EIO;
553 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
554 return -EFAULT;
555 blocking = !(filp->f_flags & O_NONBLOCK);
556 if (old_hdr.reply_len < 0)
557 return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL);
558 if (count < (SZ_SG_HEADER + 6))
559 return -EIO; /* The minimum scsi command length is 6 bytes. */
560
561 if (!(srp = sg_add_request(sfp))) {
562 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
563 return -EDOM;
564 }
565 buf += SZ_SG_HEADER;
566 __get_user(opcode, buf);
567 if (sfp->next_cmd_len > 0) {
568 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
569 SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
570 sfp->next_cmd_len = 0;
571 sg_remove_request(sfp, srp);
572 return -EIO;
573 }
574 cmd_size = sfp->next_cmd_len;
575 sfp->next_cmd_len = 0; /* reset so only this write() effected */
576 } else {
577 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
578 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
579 cmd_size = 12;
580 }
581 SCSI_LOG_TIMEOUT(4, printk(
582 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
583 /* Determine buffer size. */
584 input_size = count - cmd_size;
585 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
586 mxsize -= SZ_SG_HEADER;
587 input_size -= SZ_SG_HEADER;
588 if (input_size < 0) {
589 sg_remove_request(sfp, srp);
590 return -EIO; /* User did not pass enough bytes for this command. */
591 }
592 hp = &srp->header;
593 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
594 hp->cmd_len = (unsigned char) cmd_size;
595 hp->iovec_count = 0;
596 hp->mx_sb_len = 0;
597 if (input_size > 0)
598 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
599 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
600 else
601 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
602 hp->dxfer_len = mxsize;
603 hp->dxferp = (char __user *)buf + cmd_size;
604 hp->sbp = NULL;
605 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
606 hp->flags = input_size; /* structure abuse ... */
607 hp->pack_id = old_hdr.pack_id;
608 hp->usr_ptr = NULL;
609 if (__copy_from_user(cmnd, buf, cmd_size))
610 return -EFAULT;
611 /*
612 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
613 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
614 * is a non-zero input_size, so emit a warning.
615 */
616 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
617 static char cmd[TASK_COMM_LEN];
618 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
619 printk(KERN_WARNING
620 "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
621 "guessing data in;\n" KERN_WARNING " "
622 "program %s not setting count and/or reply_len properly\n",
623 old_hdr.reply_len - (int)SZ_SG_HEADER,
624 input_size, (unsigned int) cmnd[0],
625 current->comm);
626 strcpy(cmd, current->comm);
627 }
628 }
629 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
630 return (k < 0) ? k : count;
631 }
632
633 static ssize_t
634 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
635 size_t count, int blocking, int read_only,
636 Sg_request **o_srp)
637 {
638 int k;
639 Sg_request *srp;
640 sg_io_hdr_t *hp;
641 unsigned char cmnd[MAX_COMMAND_SIZE];
642 int timeout;
643 unsigned long ul_timeout;
644
645 if (count < SZ_SG_IO_HDR)
646 return -EINVAL;
647 if (!access_ok(VERIFY_READ, buf, count))
648 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
649
650 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
651 if (!(srp = sg_add_request(sfp))) {
652 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
653 return -EDOM;
654 }
655 hp = &srp->header;
656 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
657 sg_remove_request(sfp, srp);
658 return -EFAULT;
659 }
660 if (hp->interface_id != 'S') {
661 sg_remove_request(sfp, srp);
662 return -ENOSYS;
663 }
664 if (hp->flags & SG_FLAG_MMAP_IO) {
665 if (hp->dxfer_len > sfp->reserve.bufflen) {
666 sg_remove_request(sfp, srp);
667 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
668 }
669 if (hp->flags & SG_FLAG_DIRECT_IO) {
670 sg_remove_request(sfp, srp);
671 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
672 }
673 if (sg_res_in_use(sfp)) {
674 sg_remove_request(sfp, srp);
675 return -EBUSY; /* reserve buffer already being used */
676 }
677 }
678 ul_timeout = msecs_to_jiffies(srp->header.timeout);
679 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
680 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
681 sg_remove_request(sfp, srp);
682 return -EMSGSIZE;
683 }
684 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
685 sg_remove_request(sfp, srp);
686 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
687 }
688 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
689 sg_remove_request(sfp, srp);
690 return -EFAULT;
691 }
692 if (read_only && !blk_verify_command(file, cmnd)) {
693 sg_remove_request(sfp, srp);
694 return -EPERM;
695 }
696 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
697 if (k < 0)
698 return k;
699 if (o_srp)
700 *o_srp = srp;
701 return count;
702 }
703
704 static int
705 sg_common_write(Sg_fd * sfp, Sg_request * srp,
706 unsigned char *cmnd, int timeout, int blocking)
707 {
708 int k, data_dir;
709 Sg_device *sdp = sfp->parentdp;
710 sg_io_hdr_t *hp = &srp->header;
711
712 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
713 hp->status = 0;
714 hp->masked_status = 0;
715 hp->msg_status = 0;
716 hp->info = 0;
717 hp->host_status = 0;
718 hp->driver_status = 0;
719 hp->resid = 0;
720 SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
721 (int) cmnd[0], (int) hp->cmd_len));
722
723 if ((k = sg_start_req(srp))) {
724 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
725 sg_finish_rem_req(srp);
726 return k; /* probably out of space --> ENOMEM */
727 }
728 if ((k = sg_write_xfer(srp))) {
729 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n"));
730 sg_finish_rem_req(srp);
731 return k;
732 }
733 if (sdp->detached) {
734 sg_finish_rem_req(srp);
735 return -ENODEV;
736 }
737
738 switch (hp->dxfer_direction) {
739 case SG_DXFER_TO_FROM_DEV:
740 case SG_DXFER_FROM_DEV:
741 data_dir = DMA_FROM_DEVICE;
742 break;
743 case SG_DXFER_TO_DEV:
744 data_dir = DMA_TO_DEVICE;
745 break;
746 case SG_DXFER_UNKNOWN:
747 data_dir = DMA_BIDIRECTIONAL;
748 break;
749 default:
750 data_dir = DMA_NONE;
751 break;
752 }
753 hp->duration = jiffies_to_msecs(jiffies);
754 /* Now send everything of to mid-level. The next time we hear about this
755 packet is when sg_cmd_done() is called (i.e. a callback). */
756 if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer,
757 hp->dxfer_len, srp->data.k_use_sg, timeout,
758 SG_DEFAULT_RETRIES, srp, sg_cmd_done,
759 GFP_ATOMIC)) {
760 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n"));
761 /*
762 * most likely out of mem, but could also be a bad map
763 */
764 sg_finish_rem_req(srp);
765 return -ENOMEM;
766 } else
767 return 0;
768 }
769
770 static int
771 sg_srp_done(Sg_request *srp, Sg_fd *sfp)
772 {
773 unsigned long iflags;
774 int done;
775
776 read_lock_irqsave(&sfp->rq_list_lock, iflags);
777 done = srp->done;
778 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
779 return done;
780 }
781
782 static int
783 sg_ioctl(struct inode *inode, struct file *filp,
784 unsigned int cmd_in, unsigned long arg)
785 {
786 void __user *p = (void __user *)arg;
787 int __user *ip = p;
788 int result, val, read_only;
789 Sg_device *sdp;
790 Sg_fd *sfp;
791 Sg_request *srp;
792 unsigned long iflags;
793
794 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
795 return -ENXIO;
796 SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
797 sdp->disk->disk_name, (int) cmd_in));
798 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
799
800 switch (cmd_in) {
801 case SG_IO:
802 {
803 int blocking = 1; /* ignore O_NONBLOCK flag */
804
805 if (sdp->detached)
806 return -ENODEV;
807 if (!scsi_block_when_processing_errors(sdp->device))
808 return -ENXIO;
809 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
810 return -EFAULT;
811 result =
812 sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
813 blocking, read_only, &srp);
814 if (result < 0)
815 return result;
816 srp->sg_io_owned = 1;
817 while (1) {
818 result = 0; /* following macro to beat race condition */
819 __wait_event_interruptible(sfp->read_wait,
820 (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)),
821 result);
822 if (sdp->detached)
823 return -ENODEV;
824 if (sfp->closed)
825 return 0; /* request packet dropped already */
826 if (0 == result)
827 break;
828 srp->orphan = 1;
829 return result; /* -ERESTARTSYS because signal hit process */
830 }
831 write_lock_irqsave(&sfp->rq_list_lock, iflags);
832 srp->done = 2;
833 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
834 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
835 return (result < 0) ? result : 0;
836 }
837 case SG_SET_TIMEOUT:
838 result = get_user(val, ip);
839 if (result)
840 return result;
841 if (val < 0)
842 return -EIO;
843 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
844 val = MULDIV (INT_MAX, USER_HZ, HZ);
845 sfp->timeout_user = val;
846 sfp->timeout = MULDIV (val, HZ, USER_HZ);
847
848 return 0;
849 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
850 /* strange ..., for backward compatibility */
851 return sfp->timeout_user;
852 case SG_SET_FORCE_LOW_DMA:
853 result = get_user(val, ip);
854 if (result)
855 return result;
856 if (val) {
857 sfp->low_dma = 1;
858 if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
859 val = (int) sfp->reserve.bufflen;
860 sg_remove_scat(&sfp->reserve);
861 sg_build_reserve(sfp, val);
862 }
863 } else {
864 if (sdp->detached)
865 return -ENODEV;
866 sfp->low_dma = sdp->device->host->unchecked_isa_dma;
867 }
868 return 0;
869 case SG_GET_LOW_DMA:
870 return put_user((int) sfp->low_dma, ip);
871 case SG_GET_SCSI_ID:
872 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
873 return -EFAULT;
874 else {
875 sg_scsi_id_t __user *sg_idp = p;
876
877 if (sdp->detached)
878 return -ENODEV;
879 __put_user((int) sdp->device->host->host_no,
880 &sg_idp->host_no);
881 __put_user((int) sdp->device->channel,
882 &sg_idp->channel);
883 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
884 __put_user((int) sdp->device->lun, &sg_idp->lun);
885 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
886 __put_user((short) sdp->device->host->cmd_per_lun,
887 &sg_idp->h_cmd_per_lun);
888 __put_user((short) sdp->device->queue_depth,
889 &sg_idp->d_queue_depth);
890 __put_user(0, &sg_idp->unused[0]);
891 __put_user(0, &sg_idp->unused[1]);
892 return 0;
893 }
894 case SG_SET_FORCE_PACK_ID:
895 result = get_user(val, ip);
896 if (result)
897 return result;
898 sfp->force_packid = val ? 1 : 0;
899 return 0;
900 case SG_GET_PACK_ID:
901 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
902 return -EFAULT;
903 read_lock_irqsave(&sfp->rq_list_lock, iflags);
904 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
905 if ((1 == srp->done) && (!srp->sg_io_owned)) {
906 read_unlock_irqrestore(&sfp->rq_list_lock,
907 iflags);
908 __put_user(srp->header.pack_id, ip);
909 return 0;
910 }
911 }
912 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
913 __put_user(-1, ip);
914 return 0;
915 case SG_GET_NUM_WAITING:
916 read_lock_irqsave(&sfp->rq_list_lock, iflags);
917 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
918 if ((1 == srp->done) && (!srp->sg_io_owned))
919 ++val;
920 }
921 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
922 return put_user(val, ip);
923 case SG_GET_SG_TABLESIZE:
924 return put_user(sdp->sg_tablesize, ip);
925 case SG_SET_RESERVED_SIZE:
926 result = get_user(val, ip);
927 if (result)
928 return result;
929 if (val < 0)
930 return -EINVAL;
931 val = min_t(int, val,
932 sdp->device->request_queue->max_sectors * 512);
933 if (val != sfp->reserve.bufflen) {
934 if (sg_res_in_use(sfp) || sfp->mmap_called)
935 return -EBUSY;
936 sg_remove_scat(&sfp->reserve);
937 sg_build_reserve(sfp, val);
938 }
939 return 0;
940 case SG_GET_RESERVED_SIZE:
941 val = min_t(int, sfp->reserve.bufflen,
942 sdp->device->request_queue->max_sectors * 512);
943 return put_user(val, ip);
944 case SG_SET_COMMAND_Q:
945 result = get_user(val, ip);
946 if (result)
947 return result;
948 sfp->cmd_q = val ? 1 : 0;
949 return 0;
950 case SG_GET_COMMAND_Q:
951 return put_user((int) sfp->cmd_q, ip);
952 case SG_SET_KEEP_ORPHAN:
953 result = get_user(val, ip);
954 if (result)
955 return result;
956 sfp->keep_orphan = val;
957 return 0;
958 case SG_GET_KEEP_ORPHAN:
959 return put_user((int) sfp->keep_orphan, ip);
960 case SG_NEXT_CMD_LEN:
961 result = get_user(val, ip);
962 if (result)
963 return result;
964 sfp->next_cmd_len = (val > 0) ? val : 0;
965 return 0;
966 case SG_GET_VERSION_NUM:
967 return put_user(sg_version_num, ip);
968 case SG_GET_ACCESS_COUNT:
969 /* faked - we don't have a real access count anymore */
970 val = (sdp->device ? 1 : 0);
971 return put_user(val, ip);
972 case SG_GET_REQUEST_TABLE:
973 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
974 return -EFAULT;
975 else {
976 sg_req_info_t *rinfo;
977 unsigned int ms;
978
979 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
980 GFP_KERNEL);
981 if (!rinfo)
982 return -ENOMEM;
983 read_lock_irqsave(&sfp->rq_list_lock, iflags);
984 for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
985 ++val, srp = srp ? srp->nextrp : srp) {
986 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
987 if (srp) {
988 rinfo[val].req_state = srp->done + 1;
989 rinfo[val].problem =
990 srp->header.masked_status &
991 srp->header.host_status &
992 srp->header.driver_status;
993 if (srp->done)
994 rinfo[val].duration =
995 srp->header.duration;
996 else {
997 ms = jiffies_to_msecs(jiffies);
998 rinfo[val].duration =
999 (ms > srp->header.duration) ?
1000 (ms - srp->header.duration) : 0;
1001 }
1002 rinfo[val].orphan = srp->orphan;
1003 rinfo[val].sg_io_owned =
1004 srp->sg_io_owned;
1005 rinfo[val].pack_id =
1006 srp->header.pack_id;
1007 rinfo[val].usr_ptr =
1008 srp->header.usr_ptr;
1009 }
1010 }
1011 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1012 result = __copy_to_user(p, rinfo,
1013 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1014 result = result ? -EFAULT : 0;
1015 kfree(rinfo);
1016 return result;
1017 }
1018 case SG_EMULATED_HOST:
1019 if (sdp->detached)
1020 return -ENODEV;
1021 return put_user(sdp->device->host->hostt->emulated, ip);
1022 case SG_SCSI_RESET:
1023 if (sdp->detached)
1024 return -ENODEV;
1025 if (filp->f_flags & O_NONBLOCK) {
1026 if (scsi_host_in_recovery(sdp->device->host))
1027 return -EBUSY;
1028 } else if (!scsi_block_when_processing_errors(sdp->device))
1029 return -EBUSY;
1030 result = get_user(val, ip);
1031 if (result)
1032 return result;
1033 if (SG_SCSI_RESET_NOTHING == val)
1034 return 0;
1035 switch (val) {
1036 case SG_SCSI_RESET_DEVICE:
1037 val = SCSI_TRY_RESET_DEVICE;
1038 break;
1039 case SG_SCSI_RESET_BUS:
1040 val = SCSI_TRY_RESET_BUS;
1041 break;
1042 case SG_SCSI_RESET_HOST:
1043 val = SCSI_TRY_RESET_HOST;
1044 break;
1045 default:
1046 return -EINVAL;
1047 }
1048 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1049 return -EACCES;
1050 return (scsi_reset_provider(sdp->device, val) ==
1051 SUCCESS) ? 0 : -EIO;
1052 case SCSI_IOCTL_SEND_COMMAND:
1053 if (sdp->detached)
1054 return -ENODEV;
1055 if (read_only) {
1056 unsigned char opcode = WRITE_6;
1057 Scsi_Ioctl_Command __user *siocp = p;
1058
1059 if (copy_from_user(&opcode, siocp->data, 1))
1060 return -EFAULT;
1061 if (!blk_verify_command(filp, &opcode))
1062 return -EPERM;
1063 }
1064 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);
1065 case SG_SET_DEBUG:
1066 result = get_user(val, ip);
1067 if (result)
1068 return result;
1069 sdp->sgdebug = (char) val;
1070 return 0;
1071 case SCSI_IOCTL_GET_IDLUN:
1072 case SCSI_IOCTL_GET_BUS_NUMBER:
1073 case SCSI_IOCTL_PROBE_HOST:
1074 case SG_GET_TRANSFORM:
1075 if (sdp->detached)
1076 return -ENODEV;
1077 return scsi_ioctl(sdp->device, cmd_in, p);
1078 case BLKSECTGET:
1079 return put_user(sdp->device->request_queue->max_sectors * 512,
1080 ip);
1081 case BLKTRACESETUP:
1082 return blk_trace_setup(sdp->device->request_queue,
1083 sdp->disk->disk_name,
1084 sdp->device->sdev_gendev.devt,
1085 (char *)arg);
1086 case BLKTRACESTART:
1087 return blk_trace_startstop(sdp->device->request_queue, 1);
1088 case BLKTRACESTOP:
1089 return blk_trace_startstop(sdp->device->request_queue, 0);
1090 case BLKTRACETEARDOWN:
1091 return blk_trace_remove(sdp->device->request_queue);
1092 default:
1093 if (read_only)
1094 return -EPERM; /* don't know so take safe approach */
1095 return scsi_ioctl(sdp->device, cmd_in, p);
1096 }
1097 }
1098
1099 #ifdef CONFIG_COMPAT
1100 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1101 {
1102 Sg_device *sdp;
1103 Sg_fd *sfp;
1104 struct scsi_device *sdev;
1105
1106 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1107 return -ENXIO;
1108
1109 sdev = sdp->device;
1110 if (sdev->host->hostt->compat_ioctl) {
1111 int ret;
1112
1113 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1114
1115 return ret;
1116 }
1117
1118 return -ENOIOCTLCMD;
1119 }
1120 #endif
1121
1122 static unsigned int
1123 sg_poll(struct file *filp, poll_table * wait)
1124 {
1125 unsigned int res = 0;
1126 Sg_device *sdp;
1127 Sg_fd *sfp;
1128 Sg_request *srp;
1129 int count = 0;
1130 unsigned long iflags;
1131
1132 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1133 || sfp->closed)
1134 return POLLERR;
1135 poll_wait(filp, &sfp->read_wait, wait);
1136 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1137 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1138 /* if any read waiting, flag it */
1139 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1140 res = POLLIN | POLLRDNORM;
1141 ++count;
1142 }
1143 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1144
1145 if (sdp->detached)
1146 res |= POLLHUP;
1147 else if (!sfp->cmd_q) {
1148 if (0 == count)
1149 res |= POLLOUT | POLLWRNORM;
1150 } else if (count < SG_MAX_QUEUE)
1151 res |= POLLOUT | POLLWRNORM;
1152 SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1153 sdp->disk->disk_name, (int) res));
1154 return res;
1155 }
1156
1157 static int
1158 sg_fasync(int fd, struct file *filp, int mode)
1159 {
1160 int retval;
1161 Sg_device *sdp;
1162 Sg_fd *sfp;
1163
1164 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1165 return -ENXIO;
1166 SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1167 sdp->disk->disk_name, mode));
1168
1169 retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
1170 return (retval < 0) ? retval : 0;
1171 }
1172
1173 static int
1174 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1175 {
1176 Sg_fd *sfp;
1177 unsigned long offset, len, sa;
1178 Sg_scatter_hold *rsv_schp;
1179 struct scatterlist *sg;
1180 int k;
1181
1182 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1183 return VM_FAULT_SIGBUS;
1184 rsv_schp = &sfp->reserve;
1185 offset = vmf->pgoff << PAGE_SHIFT;
1186 if (offset >= rsv_schp->bufflen)
1187 return VM_FAULT_SIGBUS;
1188 SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1189 offset, rsv_schp->k_use_sg));
1190 sg = rsv_schp->buffer;
1191 sa = vma->vm_start;
1192 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1193 ++k, sg = sg_next(sg)) {
1194 len = vma->vm_end - sa;
1195 len = (len < sg->length) ? len : sg->length;
1196 if (offset < len) {
1197 struct page *page;
1198 page = virt_to_page(page_address(sg_page(sg)) + offset);
1199 get_page(page); /* increment page count */
1200 vmf->page = page;
1201 return 0; /* success */
1202 }
1203 sa += len;
1204 offset -= len;
1205 }
1206
1207 return VM_FAULT_SIGBUS;
1208 }
1209
1210 static struct vm_operations_struct sg_mmap_vm_ops = {
1211 .fault = sg_vma_fault,
1212 };
1213
1214 static int
1215 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1216 {
1217 Sg_fd *sfp;
1218 unsigned long req_sz, len, sa;
1219 Sg_scatter_hold *rsv_schp;
1220 int k;
1221 struct scatterlist *sg;
1222
1223 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1224 return -ENXIO;
1225 req_sz = vma->vm_end - vma->vm_start;
1226 SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1227 (void *) vma->vm_start, (int) req_sz));
1228 if (vma->vm_pgoff)
1229 return -EINVAL; /* want no offset */
1230 rsv_schp = &sfp->reserve;
1231 if (req_sz > rsv_schp->bufflen)
1232 return -ENOMEM; /* cannot map more than reserved buffer */
1233
1234 sa = vma->vm_start;
1235 sg = rsv_schp->buffer;
1236 for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end);
1237 ++k, sg = sg_next(sg)) {
1238 len = vma->vm_end - sa;
1239 len = (len < sg->length) ? len : sg->length;
1240 sa += len;
1241 }
1242
1243 sfp->mmap_called = 1;
1244 vma->vm_flags |= VM_RESERVED;
1245 vma->vm_private_data = sfp;
1246 vma->vm_ops = &sg_mmap_vm_ops;
1247 return 0;
1248 }
1249
1250 /* This function is a "bottom half" handler that is called by the
1251 * mid level when a command is completed (or has failed). */
1252 static void
1253 sg_cmd_done(void *data, char *sense, int result, int resid)
1254 {
1255 Sg_request *srp = data;
1256 Sg_device *sdp = NULL;
1257 Sg_fd *sfp;
1258 unsigned long iflags;
1259 unsigned int ms;
1260
1261 if (NULL == srp) {
1262 printk(KERN_ERR "sg_cmd_done: NULL request\n");
1263 return;
1264 }
1265 sfp = srp->parentfp;
1266 if (sfp)
1267 sdp = sfp->parentdp;
1268 if ((NULL == sdp) || sdp->detached) {
1269 printk(KERN_INFO "sg_cmd_done: device detached\n");
1270 return;
1271 }
1272
1273
1274 SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1275 sdp->disk->disk_name, srp->header.pack_id, result));
1276 srp->header.resid = resid;
1277 ms = jiffies_to_msecs(jiffies);
1278 srp->header.duration = (ms > srp->header.duration) ?
1279 (ms - srp->header.duration) : 0;
1280 if (0 != result) {
1281 struct scsi_sense_hdr sshdr;
1282
1283 memcpy(srp->sense_b, sense, sizeof (srp->sense_b));
1284 srp->header.status = 0xff & result;
1285 srp->header.masked_status = status_byte(result);
1286 srp->header.msg_status = msg_byte(result);
1287 srp->header.host_status = host_byte(result);
1288 srp->header.driver_status = driver_byte(result);
1289 if ((sdp->sgdebug > 0) &&
1290 ((CHECK_CONDITION == srp->header.masked_status) ||
1291 (COMMAND_TERMINATED == srp->header.masked_status)))
1292 __scsi_print_sense("sg_cmd_done", sense,
1293 SCSI_SENSE_BUFFERSIZE);
1294
1295 /* Following if statement is a patch supplied by Eric Youngdale */
1296 if (driver_byte(result) != 0
1297 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1298 && !scsi_sense_is_deferred(&sshdr)
1299 && sshdr.sense_key == UNIT_ATTENTION
1300 && sdp->device->removable) {
1301 /* Detected possible disc change. Set the bit - this */
1302 /* may be used if there are filesystems using this device */
1303 sdp->device->changed = 1;
1304 }
1305 }
1306 /* Rely on write phase to clean out srp status values, so no "else" */
1307
1308 if (sfp->closed) { /* whoops this fd already released, cleanup */
1309 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n"));
1310 sg_finish_rem_req(srp);
1311 srp = NULL;
1312 if (NULL == sfp->headrp) {
1313 SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n"));
1314 if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */
1315 scsi_device_put(sdp->device);
1316 }
1317 sfp = NULL;
1318 }
1319 } else if (srp && srp->orphan) {
1320 if (sfp->keep_orphan)
1321 srp->sg_io_owned = 0;
1322 else {
1323 sg_finish_rem_req(srp);
1324 srp = NULL;
1325 }
1326 }
1327 if (sfp && srp) {
1328 /* Now wake up any sg_read() that is waiting for this packet. */
1329 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1330 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1331 srp->done = 1;
1332 wake_up_interruptible(&sfp->read_wait);
1333 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1334 }
1335 }
1336
1337 static struct file_operations sg_fops = {
1338 .owner = THIS_MODULE,
1339 .read = sg_read,
1340 .write = sg_write,
1341 .poll = sg_poll,
1342 .ioctl = sg_ioctl,
1343 #ifdef CONFIG_COMPAT
1344 .compat_ioctl = sg_compat_ioctl,
1345 #endif
1346 .open = sg_open,
1347 .mmap = sg_mmap,
1348 .release = sg_release,
1349 .fasync = sg_fasync,
1350 };
1351
1352 static struct class *sg_sysfs_class;
1353
1354 static int sg_sysfs_valid = 0;
1355
1356 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1357 {
1358 struct request_queue *q = scsidp->request_queue;
1359 Sg_device *sdp;
1360 unsigned long iflags;
1361 int error;
1362 u32 k;
1363
1364 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1365 if (!sdp) {
1366 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1367 return ERR_PTR(-ENOMEM);
1368 }
1369 error = -ENOMEM;
1370 if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1371 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1372 goto out;
1373 }
1374
1375 write_lock_irqsave(&sg_index_lock, iflags);
1376 error = idr_get_new(&sg_index_idr, sdp, &k);
1377 write_unlock_irqrestore(&sg_index_lock, iflags);
1378
1379 if (error) {
1380 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1381 error);
1382 goto out;
1383 }
1384
1385 if (unlikely(k >= SG_MAX_DEVS))
1386 goto overflow;
1387
1388 SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1389 sprintf(disk->disk_name, "sg%d", k);
1390 disk->first_minor = k;
1391 sdp->disk = disk;
1392 sdp->device = scsidp;
1393 init_waitqueue_head(&sdp->o_excl_wait);
1394 sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
1395 sdp->index = k;
1396
1397 error = 0;
1398 out:
1399 if (error) {
1400 kfree(sdp);
1401 return ERR_PTR(error);
1402 }
1403 return sdp;
1404
1405 overflow:
1406 sdev_printk(KERN_WARNING, scsidp,
1407 "Unable to attach sg device type=%d, minor "
1408 "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1409 error = -ENODEV;
1410 goto out;
1411 }
1412
1413 static int
1414 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1415 {
1416 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1417 struct gendisk *disk;
1418 Sg_device *sdp = NULL;
1419 struct cdev * cdev = NULL;
1420 int error;
1421 unsigned long iflags;
1422
1423 disk = alloc_disk(1);
1424 if (!disk) {
1425 printk(KERN_WARNING "alloc_disk failed\n");
1426 return -ENOMEM;
1427 }
1428 disk->major = SCSI_GENERIC_MAJOR;
1429
1430 error = -ENOMEM;
1431 cdev = cdev_alloc();
1432 if (!cdev) {
1433 printk(KERN_WARNING "cdev_alloc failed\n");
1434 goto out;
1435 }
1436 cdev->owner = THIS_MODULE;
1437 cdev->ops = &sg_fops;
1438
1439 sdp = sg_alloc(disk, scsidp);
1440 if (IS_ERR(sdp)) {
1441 printk(KERN_WARNING "sg_alloc failed\n");
1442 error = PTR_ERR(sdp);
1443 goto out;
1444 }
1445
1446 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1447 if (error)
1448 goto cdev_add_err;
1449
1450 sdp->cdev = cdev;
1451 if (sg_sysfs_valid) {
1452 struct device *sg_class_member;
1453
1454 sg_class_member = device_create_drvdata(sg_sysfs_class,
1455 cl_dev->parent,
1456 MKDEV(SCSI_GENERIC_MAJOR,
1457 sdp->index),
1458 sdp,
1459 "%s", disk->disk_name);
1460 if (IS_ERR(sg_class_member)) {
1461 printk(KERN_ERR "sg_add: "
1462 "device_create failed\n");
1463 error = PTR_ERR(sg_class_member);
1464 goto cdev_add_err;
1465 }
1466 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1467 &sg_class_member->kobj, "generic");
1468 if (error)
1469 printk(KERN_ERR "sg_add: unable to make symlink "
1470 "'generic' back to sg%d\n", sdp->index);
1471 } else
1472 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1473
1474 sdev_printk(KERN_NOTICE, scsidp,
1475 "Attached scsi generic sg%d type %d\n", sdp->index,
1476 scsidp->type);
1477
1478 dev_set_drvdata(cl_dev, sdp);
1479
1480 return 0;
1481
1482 cdev_add_err:
1483 write_lock_irqsave(&sg_index_lock, iflags);
1484 idr_remove(&sg_index_idr, sdp->index);
1485 write_unlock_irqrestore(&sg_index_lock, iflags);
1486 kfree(sdp);
1487
1488 out:
1489 put_disk(disk);
1490 if (cdev)
1491 cdev_del(cdev);
1492 return error;
1493 }
1494
1495 static void
1496 sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1497 {
1498 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1499 Sg_device *sdp = dev_get_drvdata(cl_dev);
1500 unsigned long iflags;
1501 Sg_fd *sfp;
1502 Sg_fd *tsfp;
1503 Sg_request *srp;
1504 Sg_request *tsrp;
1505 int delay;
1506
1507 if (!sdp)
1508 return;
1509
1510 delay = 0;
1511 write_lock_irqsave(&sg_index_lock, iflags);
1512 if (sdp->headfp) {
1513 sdp->detached = 1;
1514 for (sfp = sdp->headfp; sfp; sfp = tsfp) {
1515 tsfp = sfp->nextfp;
1516 for (srp = sfp->headrp; srp; srp = tsrp) {
1517 tsrp = srp->nextrp;
1518 if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
1519 sg_finish_rem_req(srp);
1520 }
1521 if (sfp->closed) {
1522 scsi_device_put(sdp->device);
1523 __sg_remove_sfp(sdp, sfp);
1524 } else {
1525 delay = 1;
1526 wake_up_interruptible(&sfp->read_wait);
1527 kill_fasync(&sfp->async_qp, SIGPOLL,
1528 POLL_HUP);
1529 }
1530 }
1531 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
1532 if (NULL == sdp->headfp) {
1533 idr_remove(&sg_index_idr, sdp->index);
1534 }
1535 } else { /* nothing active, simple case */
1536 SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
1537 idr_remove(&sg_index_idr, sdp->index);
1538 }
1539 write_unlock_irqrestore(&sg_index_lock, iflags);
1540
1541 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1542 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1543 cdev_del(sdp->cdev);
1544 sdp->cdev = NULL;
1545 put_disk(sdp->disk);
1546 sdp->disk = NULL;
1547 if (NULL == sdp->headfp)
1548 kfree(sdp);
1549
1550 if (delay)
1551 msleep(10); /* dirty detach so delay device destruction */
1552 }
1553
1554 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1555 module_param_named(def_reserved_size, def_reserved_size, int,
1556 S_IRUGO | S_IWUSR);
1557 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1558
1559 MODULE_AUTHOR("Douglas Gilbert");
1560 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1561 MODULE_LICENSE("GPL");
1562 MODULE_VERSION(SG_VERSION_STR);
1563 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1564
1565 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1566 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1567 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1568 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1569
1570 static int __init
1571 init_sg(void)
1572 {
1573 int rc;
1574
1575 if (scatter_elem_sz < PAGE_SIZE) {
1576 scatter_elem_sz = PAGE_SIZE;
1577 scatter_elem_sz_prev = scatter_elem_sz;
1578 }
1579 if (def_reserved_size >= 0)
1580 sg_big_buff = def_reserved_size;
1581 else
1582 def_reserved_size = sg_big_buff;
1583
1584 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1585 SG_MAX_DEVS, "sg");
1586 if (rc)
1587 return rc;
1588 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1589 if ( IS_ERR(sg_sysfs_class) ) {
1590 rc = PTR_ERR(sg_sysfs_class);
1591 goto err_out;
1592 }
1593 sg_sysfs_valid = 1;
1594 rc = scsi_register_interface(&sg_interface);
1595 if (0 == rc) {
1596 #ifdef CONFIG_SCSI_PROC_FS
1597 sg_proc_init();
1598 #endif /* CONFIG_SCSI_PROC_FS */
1599 return 0;
1600 }
1601 class_destroy(sg_sysfs_class);
1602 err_out:
1603 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1604 return rc;
1605 }
1606
1607 static void __exit
1608 exit_sg(void)
1609 {
1610 #ifdef CONFIG_SCSI_PROC_FS
1611 sg_proc_cleanup();
1612 #endif /* CONFIG_SCSI_PROC_FS */
1613 scsi_unregister_interface(&sg_interface);
1614 class_destroy(sg_sysfs_class);
1615 sg_sysfs_valid = 0;
1616 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1617 SG_MAX_DEVS);
1618 idr_destroy(&sg_index_idr);
1619 }
1620
1621 static int
1622 sg_start_req(Sg_request * srp)
1623 {
1624 int res;
1625 Sg_fd *sfp = srp->parentfp;
1626 sg_io_hdr_t *hp = &srp->header;
1627 int dxfer_len = (int) hp->dxfer_len;
1628 int dxfer_dir = hp->dxfer_direction;
1629 Sg_scatter_hold *req_schp = &srp->data;
1630 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1631
1632 SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len));
1633 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1634 return 0;
1635 if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) &&
1636 (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) &&
1637 (!sfp->parentdp->device->host->unchecked_isa_dma)) {
1638 res = sg_build_direct(srp, sfp, dxfer_len);
1639 if (res <= 0) /* -ve -> error, 0 -> done, 1 -> try indirect */
1640 return res;
1641 }
1642 if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen))
1643 sg_link_reserve(sfp, srp, dxfer_len);
1644 else {
1645 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1646 if (res) {
1647 sg_remove_scat(req_schp);
1648 return res;
1649 }
1650 }
1651 return 0;
1652 }
1653
1654 static void
1655 sg_finish_rem_req(Sg_request * srp)
1656 {
1657 Sg_fd *sfp = srp->parentfp;
1658 Sg_scatter_hold *req_schp = &srp->data;
1659
1660 SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1661 if (srp->res_used)
1662 sg_unlink_reserve(sfp, srp);
1663 else
1664 sg_remove_scat(req_schp);
1665 sg_remove_request(sfp, srp);
1666 }
1667
1668 static int
1669 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1670 {
1671 int sg_bufflen = tablesize * sizeof(struct scatterlist);
1672 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1673
1674 /*
1675 * TODO: test without low_dma, we should not need it since
1676 * the block layer will bounce the buffer for us
1677 *
1678 * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list.
1679 */
1680 if (sfp->low_dma)
1681 gfp_flags |= GFP_DMA;
1682 schp->buffer = kzalloc(sg_bufflen, gfp_flags);
1683 if (!schp->buffer)
1684 return -ENOMEM;
1685 sg_init_table(schp->buffer, tablesize);
1686 schp->sglist_len = sg_bufflen;
1687 return tablesize; /* number of scat_gath elements allocated */
1688 }
1689
1690 #ifdef SG_ALLOW_DIO_CODE
1691 /* vvvvvvvv following code borrowed from st driver's direct IO vvvvvvvvv */
1692 /* TODO: hopefully we can use the generic block layer code */
1693
1694 /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
1695 - mapping of all pages not successful
1696 (i.e., either completely successful or fails)
1697 */
1698 static int
1699 st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
1700 unsigned long uaddr, size_t count, int rw)
1701 {
1702 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
1703 unsigned long start = uaddr >> PAGE_SHIFT;
1704 const int nr_pages = end - start;
1705 int res, i, j;
1706 struct page **pages;
1707
1708 /* User attempted Overflow! */
1709 if ((uaddr + count) < uaddr)
1710 return -EINVAL;
1711
1712 /* Too big */
1713 if (nr_pages > max_pages)
1714 return -ENOMEM;
1715
1716 /* Hmm? */
1717 if (count == 0)
1718 return 0;
1719
1720 if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL)
1721 return -ENOMEM;
1722
1723 /* Try to fault in all of the necessary pages */
1724 down_read(&current->mm->mmap_sem);
1725 /* rw==READ means read from drive, write into memory area */
1726 res = get_user_pages(
1727 current,
1728 current->mm,
1729 uaddr,
1730 nr_pages,
1731 rw == READ,
1732 0, /* don't force */
1733 pages,
1734 NULL);
1735 up_read(&current->mm->mmap_sem);
1736
1737 /* Errors and no page mapped should return here */
1738 if (res < nr_pages)
1739 goto out_unmap;
1740
1741 for (i=0; i < nr_pages; i++) {
1742 /* FIXME: flush superflous for rw==READ,
1743 * probably wrong function for rw==WRITE
1744 */
1745 flush_dcache_page(pages[i]);
1746 /* ?? Is locking needed? I don't think so */
1747 /* if (TestSetPageLocked(pages[i]))
1748 goto out_unlock; */
1749 }
1750
1751 sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK);
1752 if (nr_pages > 1) {
1753 sgl[0].length = PAGE_SIZE - sgl[0].offset;
1754 count -= sgl[0].length;
1755 for (i=1; i < nr_pages ; i++)
1756 sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0);
1757 }
1758 else {
1759 sgl[0].length = count;
1760 }
1761
1762 kfree(pages);
1763 return nr_pages;
1764
1765 out_unmap:
1766 if (res > 0) {
1767 for (j=0; j < res; j++)
1768 page_cache_release(pages[j]);
1769 res = 0;
1770 }
1771 kfree(pages);
1772 return res;
1773 }
1774
1775
1776 /* And unmap them... */
1777 static int
1778 st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
1779 int dirtied)
1780 {
1781 int i;
1782
1783 for (i=0; i < nr_pages; i++) {
1784 struct page *page = sg_page(&sgl[i]);
1785
1786 if (dirtied)
1787 SetPageDirty(page);
1788 /* unlock_page(page); */
1789 /* FIXME: cache flush missing for rw==READ
1790 * FIXME: call the correct reference counting function
1791 */
1792 page_cache_release(page);
1793 }
1794
1795 return 0;
1796 }
1797
1798 /* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */
1799 #endif
1800
1801
1802 /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */
1803 static int
1804 sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len)
1805 {
1806 #ifdef SG_ALLOW_DIO_CODE
1807 sg_io_hdr_t *hp = &srp->header;
1808 Sg_scatter_hold *schp = &srp->data;
1809 int sg_tablesize = sfp->parentdp->sg_tablesize;
1810 int mx_sc_elems, res;
1811 struct scsi_device *sdev = sfp->parentdp->device;
1812
1813 if (((unsigned long)hp->dxferp &
1814 queue_dma_alignment(sdev->request_queue)) != 0)
1815 return 1;
1816
1817 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1818 if (mx_sc_elems <= 0) {
1819 return 1;
1820 }
1821 res = st_map_user_pages(schp->buffer, mx_sc_elems,
1822 (unsigned long)hp->dxferp, dxfer_len,
1823 (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0);
1824 if (res <= 0) {
1825 sg_remove_scat(schp);
1826 return 1;
1827 }
1828 schp->k_use_sg = res;
1829 schp->dio_in_use = 1;
1830 hp->info |= SG_INFO_DIRECT_IO;
1831 return 0;
1832 #else
1833 return 1;
1834 #endif
1835 }
1836
1837 static int
1838 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1839 {
1840 struct scatterlist *sg;
1841 int ret_sz = 0, k, rem_sz, num, mx_sc_elems;
1842 int sg_tablesize = sfp->parentdp->sg_tablesize;
1843 int blk_size = buff_size;
1844 struct page *p = NULL;
1845
1846 if (blk_size < 0)
1847 return -EFAULT;
1848 if (0 == blk_size)
1849 ++blk_size; /* don't know why */
1850 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1851 blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
1852 SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1853 buff_size, blk_size));
1854
1855 /* N.B. ret_sz carried into this block ... */
1856 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1857 if (mx_sc_elems < 0)
1858 return mx_sc_elems; /* most likely -ENOMEM */
1859
1860 num = scatter_elem_sz;
1861 if (unlikely(num != scatter_elem_sz_prev)) {
1862 if (num < PAGE_SIZE) {
1863 scatter_elem_sz = PAGE_SIZE;
1864 scatter_elem_sz_prev = PAGE_SIZE;
1865 } else
1866 scatter_elem_sz_prev = num;
1867 }
1868 for (k = 0, sg = schp->buffer, rem_sz = blk_size;
1869 (rem_sz > 0) && (k < mx_sc_elems);
1870 ++k, rem_sz -= ret_sz, sg = sg_next(sg)) {
1871
1872 num = (rem_sz > scatter_elem_sz_prev) ?
1873 scatter_elem_sz_prev : rem_sz;
1874 p = sg_page_malloc(num, sfp->low_dma, &ret_sz);
1875 if (!p)
1876 return -ENOMEM;
1877
1878 if (num == scatter_elem_sz_prev) {
1879 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1880 scatter_elem_sz = ret_sz;
1881 scatter_elem_sz_prev = ret_sz;
1882 }
1883 }
1884 sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0);
1885
1886 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1887 "ret_sz=%d\n", k, num, ret_sz));
1888 } /* end of for loop */
1889
1890 schp->k_use_sg = k;
1891 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1892 "rem_sz=%d\n", k, rem_sz));
1893
1894 schp->bufflen = blk_size;
1895 if (rem_sz > 0) /* must have failed */
1896 return -ENOMEM;
1897
1898 return 0;
1899 }
1900
1901 static int
1902 sg_write_xfer(Sg_request * srp)
1903 {
1904 sg_io_hdr_t *hp = &srp->header;
1905 Sg_scatter_hold *schp = &srp->data;
1906 struct scatterlist *sg = schp->buffer;
1907 int num_xfer = 0;
1908 int j, k, onum, usglen, ksglen, res;
1909 int iovec_count = (int) hp->iovec_count;
1910 int dxfer_dir = hp->dxfer_direction;
1911 unsigned char *p;
1912 unsigned char __user *up;
1913 int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
1914
1915 if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) ||
1916 (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
1917 num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags);
1918 if (schp->bufflen < num_xfer)
1919 num_xfer = schp->bufflen;
1920 }
1921 if ((num_xfer <= 0) || (schp->dio_in_use) ||
1922 (new_interface
1923 && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
1924 return 0;
1925
1926 SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
1927 num_xfer, iovec_count, schp->k_use_sg));
1928 if (iovec_count) {
1929 onum = iovec_count;
1930 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
1931 return -EFAULT;
1932 } else
1933 onum = 1;
1934
1935 ksglen = sg->length;
1936 p = page_address(sg_page(sg));
1937 for (j = 0, k = 0; j < onum; ++j) {
1938 res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up);
1939 if (res)
1940 return res;
1941
1942 for (; p; sg = sg_next(sg), ksglen = sg->length,
1943 p = page_address(sg_page(sg))) {
1944 if (usglen <= 0)
1945 break;
1946 if (ksglen > usglen) {
1947 if (usglen >= num_xfer) {
1948 if (__copy_from_user(p, up, num_xfer))
1949 return -EFAULT;
1950 return 0;
1951 }
1952 if (__copy_from_user(p, up, usglen))
1953 return -EFAULT;
1954 p += usglen;
1955 ksglen -= usglen;
1956 break;
1957 } else {
1958 if (ksglen >= num_xfer) {
1959 if (__copy_from_user(p, up, num_xfer))
1960 return -EFAULT;
1961 return 0;
1962 }
1963 if (__copy_from_user(p, up, ksglen))
1964 return -EFAULT;
1965 up += ksglen;
1966 usglen -= ksglen;
1967 }
1968 ++k;
1969 if (k >= schp->k_use_sg)
1970 return 0;
1971 }
1972 }
1973
1974 return 0;
1975 }
1976
1977 static int
1978 sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind,
1979 int wr_xf, int *countp, unsigned char __user **up)
1980 {
1981 int num_xfer = (int) hp->dxfer_len;
1982 unsigned char __user *p = hp->dxferp;
1983 int count;
1984
1985 if (0 == sg_num) {
1986 if (wr_xf && ('\0' == hp->interface_id))
1987 count = (int) hp->flags; /* holds "old" input_size */
1988 else
1989 count = num_xfer;
1990 } else {
1991 sg_iovec_t iovec;
1992 if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC))
1993 return -EFAULT;
1994 p = iovec.iov_base;
1995 count = (int) iovec.iov_len;
1996 }
1997 if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count))
1998 return -EFAULT;
1999 if (up)
2000 *up = p;
2001 if (countp)
2002 *countp = count;
2003 return 0;
2004 }
2005
2006 static void
2007 sg_remove_scat(Sg_scatter_hold * schp)
2008 {
2009 SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
2010 if (schp->buffer && (schp->sglist_len > 0)) {
2011 struct scatterlist *sg = schp->buffer;
2012
2013 if (schp->dio_in_use) {
2014 #ifdef SG_ALLOW_DIO_CODE
2015 st_unmap_user_pages(sg, schp->k_use_sg, TRUE);
2016 #endif
2017 } else {
2018 int k;
2019
2020 for (k = 0; (k < schp->k_use_sg) && sg_page(sg);
2021 ++k, sg = sg_next(sg)) {
2022 SCSI_LOG_TIMEOUT(5, printk(
2023 "sg_remove_scat: k=%d, pg=0x%p, len=%d\n",
2024 k, sg_page(sg), sg->length));
2025 sg_page_free(sg_page(sg), sg->length);
2026 }
2027 }
2028 kfree(schp->buffer);
2029 }
2030 memset(schp, 0, sizeof (*schp));
2031 }
2032
2033 static int
2034 sg_read_xfer(Sg_request * srp)
2035 {
2036 sg_io_hdr_t *hp = &srp->header;
2037 Sg_scatter_hold *schp = &srp->data;
2038 struct scatterlist *sg = schp->buffer;
2039 int num_xfer = 0;
2040 int j, k, onum, usglen, ksglen, res;
2041 int iovec_count = (int) hp->iovec_count;
2042 int dxfer_dir = hp->dxfer_direction;
2043 unsigned char *p;
2044 unsigned char __user *up;
2045 int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
2046
2047 if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
2048 || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
2049 num_xfer = hp->dxfer_len;
2050 if (schp->bufflen < num_xfer)
2051 num_xfer = schp->bufflen;
2052 }
2053 if ((num_xfer <= 0) || (schp->dio_in_use) ||
2054 (new_interface
2055 && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
2056 return 0;
2057
2058 SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
2059 num_xfer, iovec_count, schp->k_use_sg));
2060 if (iovec_count) {
2061 onum = iovec_count;
2062 if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum))
2063 return -EFAULT;
2064 } else
2065 onum = 1;
2066
2067 p = page_address(sg_page(sg));
2068 ksglen = sg->length;
2069 for (j = 0, k = 0; j < onum; ++j) {
2070 res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up);
2071 if (res)
2072 return res;
2073
2074 for (; p; sg = sg_next(sg), ksglen = sg->length,
2075 p = page_address(sg_page(sg))) {
2076 if (usglen <= 0)
2077 break;
2078 if (ksglen > usglen) {
2079 if (usglen >= num_xfer) {
2080 if (__copy_to_user(up, p, num_xfer))
2081 return -EFAULT;
2082 return 0;
2083 }
2084 if (__copy_to_user(up, p, usglen))
2085 return -EFAULT;
2086 p += usglen;
2087 ksglen -= usglen;
2088 break;
2089 } else {
2090 if (ksglen >= num_xfer) {
2091 if (__copy_to_user(up, p, num_xfer))
2092 return -EFAULT;
2093 return 0;
2094 }
2095 if (__copy_to_user(up, p, ksglen))
2096 return -EFAULT;
2097 up += ksglen;
2098 usglen -= ksglen;
2099 }
2100 ++k;
2101 if (k >= schp->k_use_sg)
2102 return 0;
2103 }
2104 }
2105
2106 return 0;
2107 }
2108
2109 static int
2110 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
2111 {
2112 Sg_scatter_hold *schp = &srp->data;
2113 struct scatterlist *sg = schp->buffer;
2114 int k, num;
2115
2116 SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
2117 num_read_xfer));
2118 if ((!outp) || (num_read_xfer <= 0))
2119 return 0;
2120
2121 for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) {
2122 num = sg->length;
2123 if (num > num_read_xfer) {
2124 if (__copy_to_user(outp, page_address(sg_page(sg)),
2125 num_read_xfer))
2126 return -EFAULT;
2127 break;
2128 } else {
2129 if (__copy_to_user(outp, page_address(sg_page(sg)),
2130 num))
2131 return -EFAULT;
2132 num_read_xfer -= num;
2133 if (num_read_xfer <= 0)
2134 break;
2135 outp += num;
2136 }
2137 }
2138
2139 return 0;
2140 }
2141
2142 static void
2143 sg_build_reserve(Sg_fd * sfp, int req_size)
2144 {
2145 Sg_scatter_hold *schp = &sfp->reserve;
2146
2147 SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
2148 do {
2149 if (req_size < PAGE_SIZE)
2150 req_size = PAGE_SIZE;
2151 if (0 == sg_build_indirect(schp, sfp, req_size))
2152 return;
2153 else
2154 sg_remove_scat(schp);
2155 req_size >>= 1; /* divide by 2 */
2156 } while (req_size > (PAGE_SIZE / 2));
2157 }
2158
2159 static void
2160 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
2161 {
2162 Sg_scatter_hold *req_schp = &srp->data;
2163 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2164 struct scatterlist *sg = rsv_schp->buffer;
2165 int k, num, rem;
2166
2167 srp->res_used = 1;
2168 SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
2169 rem = size;
2170
2171 for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) {
2172 num = sg->length;
2173 if (rem <= num) {
2174 sfp->save_scat_len = num;
2175 sg->length = rem;
2176 req_schp->k_use_sg = k + 1;
2177 req_schp->sglist_len = rsv_schp->sglist_len;
2178 req_schp->buffer = rsv_schp->buffer;
2179
2180 req_schp->bufflen = size;
2181 req_schp->b_malloc_len = rsv_schp->b_malloc_len;
2182 break;
2183 } else
2184 rem -= num;
2185 }
2186
2187 if (k >= rsv_schp->k_use_sg)
2188 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
2189 }
2190
2191 static void
2192 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2193 {
2194 Sg_scatter_hold *req_schp = &srp->data;
2195 Sg_scatter_hold *rsv_schp = &sfp->reserve;
2196
2197 SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
2198 (int) req_schp->k_use_sg));
2199 if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) {
2200 struct scatterlist *sg = rsv_schp->buffer;
2201
2202 if (sfp->save_scat_len > 0)
2203 (sg + (req_schp->k_use_sg - 1))->length =
2204 (unsigned) sfp->save_scat_len;
2205 else
2206 SCSI_LOG_TIMEOUT(1, printk ("sg_unlink_reserve: BAD save_scat_len\n"));
2207 }
2208 req_schp->k_use_sg = 0;
2209 req_schp->bufflen = 0;
2210 req_schp->buffer = NULL;
2211 req_schp->sglist_len = 0;
2212 sfp->save_scat_len = 0;
2213 srp->res_used = 0;
2214 }
2215
2216 static Sg_request *
2217 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2218 {
2219 Sg_request *resp;
2220 unsigned long iflags;
2221
2222 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2223 for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2224 /* look for requests that are ready + not SG_IO owned */
2225 if ((1 == resp->done) && (!resp->sg_io_owned) &&
2226 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2227 resp->done = 2; /* guard against other readers */
2228 break;
2229 }
2230 }
2231 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2232 return resp;
2233 }
2234
2235 #ifdef CONFIG_SCSI_PROC_FS
2236 static Sg_request *
2237 sg_get_nth_request(Sg_fd * sfp, int nth)
2238 {
2239 Sg_request *resp;
2240 unsigned long iflags;
2241 int k;
2242
2243 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2244 for (k = 0, resp = sfp->headrp; resp && (k < nth);
2245 ++k, resp = resp->nextrp) ;
2246 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2247 return resp;
2248 }
2249 #endif
2250
2251 /* always adds to end of list */
2252 static Sg_request *
2253 sg_add_request(Sg_fd * sfp)
2254 {
2255 int k;
2256 unsigned long iflags;
2257 Sg_request *resp;
2258 Sg_request *rp = sfp->req_arr;
2259
2260 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2261 resp = sfp->headrp;
2262 if (!resp) {
2263 memset(rp, 0, sizeof (Sg_request));
2264 rp->parentfp = sfp;
2265 resp = rp;
2266 sfp->headrp = resp;
2267 } else {
2268 if (0 == sfp->cmd_q)
2269 resp = NULL; /* command queuing disallowed */
2270 else {
2271 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2272 if (!rp->parentfp)
2273 break;
2274 }
2275 if (k < SG_MAX_QUEUE) {
2276 memset(rp, 0, sizeof (Sg_request));
2277 rp->parentfp = sfp;
2278 while (resp->nextrp)
2279 resp = resp->nextrp;
2280 resp->nextrp = rp;
2281 resp = rp;
2282 } else
2283 resp = NULL;
2284 }
2285 }
2286 if (resp) {
2287 resp->nextrp = NULL;
2288 resp->header.duration = jiffies_to_msecs(jiffies);
2289 }
2290 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2291 return resp;
2292 }
2293
2294 /* Return of 1 for found; 0 for not found */
2295 static int
2296 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2297 {
2298 Sg_request *prev_rp;
2299 Sg_request *rp;
2300 unsigned long iflags;
2301 int res = 0;
2302
2303 if ((!sfp) || (!srp) || (!sfp->headrp))
2304 return res;
2305 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2306 prev_rp = sfp->headrp;
2307 if (srp == prev_rp) {
2308 sfp->headrp = prev_rp->nextrp;
2309 prev_rp->parentfp = NULL;
2310 res = 1;
2311 } else {
2312 while ((rp = prev_rp->nextrp)) {
2313 if (srp == rp) {
2314 prev_rp->nextrp = rp->nextrp;
2315 rp->parentfp = NULL;
2316 res = 1;
2317 break;
2318 }
2319 prev_rp = rp;
2320 }
2321 }
2322 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2323 return res;
2324 }
2325
2326 #ifdef CONFIG_SCSI_PROC_FS
2327 static Sg_fd *
2328 sg_get_nth_sfp(Sg_device * sdp, int nth)
2329 {
2330 Sg_fd *resp;
2331 unsigned long iflags;
2332 int k;
2333
2334 read_lock_irqsave(&sg_index_lock, iflags);
2335 for (k = 0, resp = sdp->headfp; resp && (k < nth);
2336 ++k, resp = resp->nextfp) ;
2337 read_unlock_irqrestore(&sg_index_lock, iflags);
2338 return resp;
2339 }
2340 #endif
2341
2342 static Sg_fd *
2343 sg_add_sfp(Sg_device * sdp, int dev)
2344 {
2345 Sg_fd *sfp;
2346 unsigned long iflags;
2347 int bufflen;
2348
2349 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2350 if (!sfp)
2351 return NULL;
2352
2353 init_waitqueue_head(&sfp->read_wait);
2354 rwlock_init(&sfp->rq_list_lock);
2355
2356 sfp->timeout = SG_DEFAULT_TIMEOUT;
2357 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2358 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2359 sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2360 sdp->device->host->unchecked_isa_dma : 1;
2361 sfp->cmd_q = SG_DEF_COMMAND_Q;
2362 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2363 sfp->parentdp = sdp;
2364 write_lock_irqsave(&sg_index_lock, iflags);
2365 if (!sdp->headfp)
2366 sdp->headfp = sfp;
2367 else { /* add to tail of existing list */
2368 Sg_fd *pfp = sdp->headfp;
2369 while (pfp->nextfp)
2370 pfp = pfp->nextfp;
2371 pfp->nextfp = sfp;
2372 }
2373 write_unlock_irqrestore(&sg_index_lock, iflags);
2374 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2375 if (unlikely(sg_big_buff != def_reserved_size))
2376 sg_big_buff = def_reserved_size;
2377
2378 bufflen = min_t(int, sg_big_buff,
2379 sdp->device->request_queue->max_sectors * 512);
2380 sg_build_reserve(sfp, bufflen);
2381 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2382 sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2383 return sfp;
2384 }
2385
2386 static void
2387 __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2388 {
2389 Sg_fd *fp;
2390 Sg_fd *prev_fp;
2391
2392 prev_fp = sdp->headfp;
2393 if (sfp == prev_fp)
2394 sdp->headfp = prev_fp->nextfp;
2395 else {
2396 while ((fp = prev_fp->nextfp)) {
2397 if (sfp == fp) {
2398 prev_fp->nextfp = fp->nextfp;
2399 break;
2400 }
2401 prev_fp = fp;
2402 }
2403 }
2404 if (sfp->reserve.bufflen > 0) {
2405 SCSI_LOG_TIMEOUT(6,
2406 printk("__sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2407 (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg));
2408 sg_remove_scat(&sfp->reserve);
2409 }
2410 sfp->parentdp = NULL;
2411 SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp: sfp=0x%p\n", sfp));
2412 kfree(sfp);
2413 }
2414
2415 /* Returns 0 in normal case, 1 when detached and sdp object removed */
2416 static int
2417 sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
2418 {
2419 Sg_request *srp;
2420 Sg_request *tsrp;
2421 int dirty = 0;
2422 int res = 0;
2423
2424 for (srp = sfp->headrp; srp; srp = tsrp) {
2425 tsrp = srp->nextrp;
2426 if (sg_srp_done(srp, sfp))
2427 sg_finish_rem_req(srp);
2428 else
2429 ++dirty;
2430 }
2431 if (0 == dirty) {
2432 unsigned long iflags;
2433
2434 write_lock_irqsave(&sg_index_lock, iflags);
2435 __sg_remove_sfp(sdp, sfp);
2436 if (sdp->detached && (NULL == sdp->headfp)) {
2437 idr_remove(&sg_index_idr, sdp->index);
2438 kfree(sdp);
2439 res = 1;
2440 }
2441 write_unlock_irqrestore(&sg_index_lock, iflags);
2442 } else {
2443 /* MOD_INC's to inhibit unloading sg and associated adapter driver */
2444 /* only bump the access_count if we actually succeeded in
2445 * throwing another counter on the host module */
2446 scsi_device_get(sdp->device); /* XXX: retval ignored? */
2447 sfp->closed = 1; /* flag dirty state on this fd */
2448 SCSI_LOG_TIMEOUT(1, printk("sg_remove_sfp: worrisome, %d writes pending\n",
2449 dirty));
2450 }
2451 return res;
2452 }
2453
2454 static int
2455 sg_res_in_use(Sg_fd * sfp)
2456 {
2457 const Sg_request *srp;
2458 unsigned long iflags;
2459
2460 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2461 for (srp = sfp->headrp; srp; srp = srp->nextrp)
2462 if (srp->res_used)
2463 break;
2464 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2465 return srp ? 1 : 0;
2466 }
2467
2468 /* The size fetched (value output via retSzp) set when non-NULL return */
2469 static struct page *
2470 sg_page_malloc(int rqSz, int lowDma, int *retSzp)
2471 {
2472 struct page *resp = NULL;
2473 gfp_t page_mask;
2474 int order, a_size;
2475 int resSz;
2476
2477 if ((rqSz <= 0) || (NULL == retSzp))
2478 return resp;
2479
2480 if (lowDma)
2481 page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN;
2482 else
2483 page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
2484
2485 for (order = 0, a_size = PAGE_SIZE; a_size < rqSz;
2486 order++, a_size <<= 1) ;
2487 resSz = a_size; /* rounded up if necessary */
2488 resp = alloc_pages(page_mask, order);
2489 while ((!resp) && order) {
2490 --order;
2491 a_size >>= 1; /* divide by 2, until PAGE_SIZE */
2492 resp = alloc_pages(page_mask, order); /* try half */
2493 resSz = a_size;
2494 }
2495 if (resp) {
2496 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2497 memset(page_address(resp), 0, resSz);
2498 *retSzp = resSz;
2499 }
2500 return resp;
2501 }
2502
2503 static void
2504 sg_page_free(struct page *page, int size)
2505 {
2506 int order, a_size;
2507
2508 if (!page)
2509 return;
2510 for (order = 0, a_size = PAGE_SIZE; a_size < size;
2511 order++, a_size <<= 1) ;
2512 __free_pages(page, order);
2513 }
2514
2515 #ifdef CONFIG_SCSI_PROC_FS
2516 static int
2517 sg_idr_max_id(int id, void *p, void *data)
2518 {
2519 int *k = data;
2520
2521 if (*k < id)
2522 *k = id;
2523
2524 return 0;
2525 }
2526
2527 static int
2528 sg_last_dev(void)
2529 {
2530 int k = -1;
2531 unsigned long iflags;
2532
2533 read_lock_irqsave(&sg_index_lock, iflags);
2534 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2535 read_unlock_irqrestore(&sg_index_lock, iflags);
2536 return k + 1; /* origin 1 */
2537 }
2538 #endif
2539
2540 static Sg_device *
2541 sg_get_dev(int dev)
2542 {
2543 Sg_device *sdp;
2544 unsigned long iflags;
2545
2546 read_lock_irqsave(&sg_index_lock, iflags);
2547 sdp = idr_find(&sg_index_idr, dev);
2548 read_unlock_irqrestore(&sg_index_lock, iflags);
2549
2550 return sdp;
2551 }
2552
2553 #ifdef CONFIG_SCSI_PROC_FS
2554
2555 static struct proc_dir_entry *sg_proc_sgp = NULL;
2556
2557 static char sg_proc_sg_dirname[] = "scsi/sg";
2558
2559 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2560
2561 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2562 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2563 size_t count, loff_t *off);
2564 static struct file_operations adio_fops = {
2565 /* .owner, .read and .llseek added in sg_proc_init() */
2566 .open = sg_proc_single_open_adio,
2567 .write = sg_proc_write_adio,
2568 .release = single_release,
2569 };
2570
2571 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2572 static ssize_t sg_proc_write_dressz(struct file *filp,
2573 const char __user *buffer, size_t count, loff_t *off);
2574 static struct file_operations dressz_fops = {
2575 .open = sg_proc_single_open_dressz,
2576 .write = sg_proc_write_dressz,
2577 .release = single_release,
2578 };
2579
2580 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2581 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2582 static struct file_operations version_fops = {
2583 .open = sg_proc_single_open_version,
2584 .release = single_release,
2585 };
2586
2587 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2588 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2589 static struct file_operations devhdr_fops = {
2590 .open = sg_proc_single_open_devhdr,
2591 .release = single_release,
2592 };
2593
2594 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2595 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2596 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2597 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2598 static void dev_seq_stop(struct seq_file *s, void *v);
2599 static struct file_operations dev_fops = {
2600 .open = sg_proc_open_dev,
2601 .release = seq_release,
2602 };
2603 static struct seq_operations dev_seq_ops = {
2604 .start = dev_seq_start,
2605 .next = dev_seq_next,
2606 .stop = dev_seq_stop,
2607 .show = sg_proc_seq_show_dev,
2608 };
2609
2610 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2611 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2612 static struct file_operations devstrs_fops = {
2613 .open = sg_proc_open_devstrs,
2614 .release = seq_release,
2615 };
2616 static struct seq_operations devstrs_seq_ops = {
2617 .start = dev_seq_start,
2618 .next = dev_seq_next,
2619 .stop = dev_seq_stop,
2620 .show = sg_proc_seq_show_devstrs,
2621 };
2622
2623 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2624 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2625 static struct file_operations debug_fops = {
2626 .open = sg_proc_open_debug,
2627 .release = seq_release,
2628 };
2629 static struct seq_operations debug_seq_ops = {
2630 .start = dev_seq_start,
2631 .next = dev_seq_next,
2632 .stop = dev_seq_stop,
2633 .show = sg_proc_seq_show_debug,
2634 };
2635
2636
2637 struct sg_proc_leaf {
2638 const char * name;
2639 struct file_operations * fops;
2640 };
2641
2642 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2643 {"allow_dio", &adio_fops},
2644 {"debug", &debug_fops},
2645 {"def_reserved_size", &dressz_fops},
2646 {"device_hdr", &devhdr_fops},
2647 {"devices", &dev_fops},
2648 {"device_strs", &devstrs_fops},
2649 {"version", &version_fops}
2650 };
2651
2652 static int
2653 sg_proc_init(void)
2654 {
2655 int k, mask;
2656 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2657 struct sg_proc_leaf * leaf;
2658
2659 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2660 if (!sg_proc_sgp)
2661 return 1;
2662 for (k = 0; k < num_leaves; ++k) {
2663 leaf = &sg_proc_leaf_arr[k];
2664 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2665 leaf->fops->owner = THIS_MODULE;
2666 leaf->fops->read = seq_read;
2667 leaf->fops->llseek = seq_lseek;
2668 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2669 }
2670 return 0;
2671 }
2672
2673 static void
2674 sg_proc_cleanup(void)
2675 {
2676 int k;
2677 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2678
2679 if (!sg_proc_sgp)
2680 return;
2681 for (k = 0; k < num_leaves; ++k)
2682 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2683 remove_proc_entry(sg_proc_sg_dirname, NULL);
2684 }
2685
2686
2687 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2688 {
2689 seq_printf(s, "%d\n", *((int *)s->private));
2690 return 0;
2691 }
2692
2693 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2694 {
2695 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2696 }
2697
2698 static ssize_t
2699 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2700 size_t count, loff_t *off)
2701 {
2702 int num;
2703 char buff[11];
2704
2705 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2706 return -EACCES;
2707 num = (count < 10) ? count : 10;
2708 if (copy_from_user(buff, buffer, num))
2709 return -EFAULT;
2710 buff[num] = '\0';
2711 sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2712 return count;
2713 }
2714
2715 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2716 {
2717 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2718 }
2719
2720 static ssize_t
2721 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2722 size_t count, loff_t *off)
2723 {
2724 int num;
2725 unsigned long k = ULONG_MAX;
2726 char buff[11];
2727
2728 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2729 return -EACCES;
2730 num = (count < 10) ? count : 10;
2731 if (copy_from_user(buff, buffer, num))
2732 return -EFAULT;
2733 buff[num] = '\0';
2734 k = simple_strtoul(buff, NULL, 10);
2735 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2736 sg_big_buff = k;
2737 return count;
2738 }
2739 return -ERANGE;
2740 }
2741
2742 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2743 {
2744 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2745 sg_version_date);
2746 return 0;
2747 }
2748
2749 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2750 {
2751 return single_open(file, sg_proc_seq_show_version, NULL);
2752 }
2753
2754 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2755 {
2756 seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2757 "online\n");
2758 return 0;
2759 }
2760
2761 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2762 {
2763 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2764 }
2765
2766 struct sg_proc_deviter {
2767 loff_t index;
2768 size_t max;
2769 };
2770
2771 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2772 {
2773 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2774
2775 s->private = it;
2776 if (! it)
2777 return NULL;
2778
2779 it->index = *pos;
2780 it->max = sg_last_dev();
2781 if (it->index >= it->max)
2782 return NULL;
2783 return it;
2784 }
2785
2786 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2787 {
2788 struct sg_proc_deviter * it = s->private;
2789
2790 *pos = ++it->index;
2791 return (it->index < it->max) ? it : NULL;
2792 }
2793
2794 static void dev_seq_stop(struct seq_file *s, void *v)
2795 {
2796 kfree(s->private);
2797 }
2798
2799 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2800 {
2801 return seq_open(file, &dev_seq_ops);
2802 }
2803
2804 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2805 {
2806 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2807 Sg_device *sdp;
2808 struct scsi_device *scsidp;
2809
2810 sdp = it ? sg_get_dev(it->index) : NULL;
2811 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2812 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2813 scsidp->host->host_no, scsidp->channel,
2814 scsidp->id, scsidp->lun, (int) scsidp->type,
2815 1,
2816 (int) scsidp->queue_depth,
2817 (int) scsidp->device_busy,
2818 (int) scsi_device_online(scsidp));
2819 else
2820 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2821 return 0;
2822 }
2823
2824 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2825 {
2826 return seq_open(file, &devstrs_seq_ops);
2827 }
2828
2829 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2830 {
2831 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2832 Sg_device *sdp;
2833 struct scsi_device *scsidp;
2834
2835 sdp = it ? sg_get_dev(it->index) : NULL;
2836 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2837 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2838 scsidp->vendor, scsidp->model, scsidp->rev);
2839 else
2840 seq_printf(s, "<no active device>\n");
2841 return 0;
2842 }
2843
2844 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2845 {
2846 int k, m, new_interface, blen, usg;
2847 Sg_request *srp;
2848 Sg_fd *fp;
2849 const sg_io_hdr_t *hp;
2850 const char * cp;
2851 unsigned int ms;
2852
2853 for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) {
2854 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2855 "(res)sgat=%d low_dma=%d\n", k + 1,
2856 jiffies_to_msecs(fp->timeout),
2857 fp->reserve.bufflen,
2858 (int) fp->reserve.k_use_sg,
2859 (int) fp->low_dma);
2860 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2861 (int) fp->cmd_q, (int) fp->force_packid,
2862 (int) fp->keep_orphan, (int) fp->closed);
2863 for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) {
2864 hp = &srp->header;
2865 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2866 if (srp->res_used) {
2867 if (new_interface &&
2868 (SG_FLAG_MMAP_IO & hp->flags))
2869 cp = " mmap>> ";
2870 else
2871 cp = " rb>> ";
2872 } else {
2873 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2874 cp = " dio>> ";
2875 else
2876 cp = " ";
2877 }
2878 seq_printf(s, cp);
2879 blen = srp->data.bufflen;
2880 usg = srp->data.k_use_sg;
2881 seq_printf(s, srp->done ?
2882 ((1 == srp->done) ? "rcv:" : "fin:")
2883 : "act:");
2884 seq_printf(s, " id=%d blen=%d",
2885 srp->header.pack_id, blen);
2886 if (srp->done)
2887 seq_printf(s, " dur=%d", hp->duration);
2888 else {
2889 ms = jiffies_to_msecs(jiffies);
2890 seq_printf(s, " t_o/elap=%d/%d",
2891 (new_interface ? hp->timeout :
2892 jiffies_to_msecs(fp->timeout)),
2893 (ms > hp->duration ? ms - hp->duration : 0));
2894 }
2895 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2896 (int) srp->data.cmd_opcode);
2897 }
2898 if (0 == m)
2899 seq_printf(s, " No requests active\n");
2900 }
2901 }
2902
2903 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2904 {
2905 return seq_open(file, &debug_seq_ops);
2906 }
2907
2908 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2909 {
2910 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2911 Sg_device *sdp;
2912
2913 if (it && (0 == it->index)) {
2914 seq_printf(s, "max_active_device=%d(origin 1)\n",
2915 (int)it->max);
2916 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2917 }
2918 sdp = it ? sg_get_dev(it->index) : NULL;
2919 if (sdp) {
2920 struct scsi_device *scsidp = sdp->device;
2921
2922 if (NULL == scsidp) {
2923 seq_printf(s, "device %d detached ??\n",
2924 (int)it->index);
2925 return 0;
2926 }
2927
2928 if (sg_get_nth_sfp(sdp, 0)) {
2929 seq_printf(s, " >>> device=%s ",
2930 sdp->disk->disk_name);
2931 if (sdp->detached)
2932 seq_printf(s, "detached pending close ");
2933 else
2934 seq_printf
2935 (s, "scsi%d chan=%d id=%d lun=%d em=%d",
2936 scsidp->host->host_no,
2937 scsidp->channel, scsidp->id,
2938 scsidp->lun,
2939 scsidp->host->hostt->emulated);
2940 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2941 sdp->sg_tablesize, sdp->exclude);
2942 }
2943 sg_proc_debug_helper(s, sdp);
2944 }
2945 return 0;
2946 }
2947
2948 #endif /* CONFIG_SCSI_PROC_FS */
2949
2950 module_init(init_sg);
2951 module_exit(exit_sg);
Linux kernel - Deliverables
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