Input: evdev - never leave the client buffer empty after write
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / scsi / sg.c
blobef752b248c4d5ef7842589299d75a2297ec8178e
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
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
12 * Modified 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
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.
21 static int sg_version_num = 30534; /* 2 digits for each component */
22 #define SG_VERSION_STR "3.5.34"
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).
31 #include <linux/module.h>
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/slab.h>
42 #include <linux/fcntl.h>
43 #include <linux/init.h>
44 #include <linux/poll.h>
45 #include <linux/moduleparam.h>
46 #include <linux/cdev.h>
47 #include <linux/idr.h>
48 #include <linux/seq_file.h>
49 #include <linux/blkdev.h>
50 #include <linux/delay.h>
51 #include <linux/blktrace_api.h>
52 #include <linux/smp_lock.h>
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>
61 #include "scsi_logging.h"
63 #ifdef CONFIG_SCSI_PROC_FS
64 #include <linux/proc_fs.h>
65 static char *sg_version_date = "20061027";
67 static int sg_proc_init(void);
68 static void sg_proc_cleanup(void);
69 #endif
71 #define SG_ALLOW_DIO_DEF 0
73 #define SG_MAX_DEVS 32768
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.
84 #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
86 #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
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;
98 static int scatter_elem_sz = SG_SCATTER_SZ;
99 static int scatter_elem_sz_prev = SG_SCATTER_SZ;
101 #define SG_SECTOR_SZ 512
103 static int sg_add(struct device *, struct class_interface *);
104 static void sg_remove(struct device *, struct class_interface *);
106 static DEFINE_IDR(sg_index_idr);
107 static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock
108 file descriptor list for device */
110 static struct class_interface sg_interface = {
111 .add_dev = sg_add,
112 .remove_dev = sg_remove,
115 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
116 unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
117 unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
118 unsigned bufflen; /* Size of (aggregate) data buffer */
119 struct page **pages;
120 int page_order;
121 char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */
122 unsigned char cmd_opcode; /* first byte of command */
123 } Sg_scatter_hold;
125 struct sg_device; /* forward declarations */
126 struct sg_fd;
128 typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */
129 struct sg_request *nextrp; /* NULL -> tail request (slist) */
130 struct sg_fd *parentfp; /* NULL -> not in use */
131 Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
132 sg_io_hdr_t header; /* scsi command+info, see <scsi/sg.h> */
133 unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
134 char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
135 char orphan; /* 1 -> drop on sight, 0 -> normal */
136 char sg_io_owned; /* 1 -> packet belongs to SG_IO */
137 volatile char done; /* 0->before bh, 1->before read, 2->read */
138 struct request *rq;
139 struct bio *bio;
140 struct execute_work ew;
141 } Sg_request;
143 typedef struct sg_fd { /* holds the state of a file descriptor */
144 struct list_head sfd_siblings;
145 struct sg_device *parentdp; /* owning device */
146 wait_queue_head_t read_wait; /* queue read until command done */
147 rwlock_t rq_list_lock; /* protect access to list in req_arr */
148 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
149 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */
150 Sg_scatter_hold reserve; /* buffer held for this file descriptor */
151 unsigned save_scat_len; /* original length of trunc. scat. element */
152 Sg_request *headrp; /* head of request slist, NULL->empty */
153 struct fasync_struct *async_qp; /* used by asynchronous notification */
154 Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
155 char low_dma; /* as in parent but possibly overridden to 1 */
156 char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
157 volatile char closed; /* 1 -> fd closed but request(s) outstanding */
158 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
159 char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
160 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */
161 char mmap_called; /* 0 -> mmap() never called on this fd */
162 struct kref f_ref;
163 struct execute_work ew;
164 } Sg_fd;
166 typedef struct sg_device { /* holds the state of each scsi generic device */
167 struct scsi_device *device;
168 wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
169 int sg_tablesize; /* adapter's max scatter-gather table size */
170 u32 index; /* device index number */
171 struct list_head sfds;
172 volatile char detached; /* 0->attached, 1->detached pending removal */
173 volatile char exclude; /* opened for exclusive access */
174 char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
175 struct gendisk *disk;
176 struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */
177 struct kref d_ref;
178 } Sg_device;
180 /* tasklet or soft irq callback */
181 static void sg_rq_end_io(struct request *rq, int uptodate);
182 static int sg_start_req(Sg_request *srp, unsigned char *cmd);
183 static int sg_finish_rem_req(Sg_request * srp);
184 static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
185 static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
186 Sg_request * srp);
187 static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
188 const char __user *buf, size_t count, int blocking,
189 int read_only, int sg_io_owned, Sg_request **o_srp);
190 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
191 unsigned char *cmnd, int timeout, int blocking);
192 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
193 static void sg_remove_scat(Sg_scatter_hold * schp);
194 static void sg_build_reserve(Sg_fd * sfp, int req_size);
195 static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
196 static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
197 static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
198 static void sg_remove_sfp(struct kref *);
199 static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
200 static Sg_request *sg_add_request(Sg_fd * sfp);
201 static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
202 static int sg_res_in_use(Sg_fd * sfp);
203 static Sg_device *sg_get_dev(int dev);
204 static void sg_put_dev(Sg_device *sdp);
206 #define SZ_SG_HEADER sizeof(struct sg_header)
207 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
208 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
209 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
211 static int sg_allow_access(struct file *filp, unsigned char *cmd)
213 struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
215 if (sfp->parentdp->device->type == TYPE_SCANNER)
216 return 0;
218 return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
221 static int
222 sg_open(struct inode *inode, struct file *filp)
224 int dev = iminor(inode);
225 int flags = filp->f_flags;
226 struct request_queue *q;
227 Sg_device *sdp;
228 Sg_fd *sfp;
229 int res;
230 int retval;
232 lock_kernel();
233 nonseekable_open(inode, filp);
234 SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
235 sdp = sg_get_dev(dev);
236 if (IS_ERR(sdp)) {
237 retval = PTR_ERR(sdp);
238 sdp = NULL;
239 goto sg_put;
242 /* This driver's module count bumped by fops_get in <linux/fs.h> */
243 /* Prevent the device driver from vanishing while we sleep */
244 retval = scsi_device_get(sdp->device);
245 if (retval)
246 goto sg_put;
248 if (!((flags & O_NONBLOCK) ||
249 scsi_block_when_processing_errors(sdp->device))) {
250 retval = -ENXIO;
251 /* we are in error recovery for this device */
252 goto error_out;
255 if (flags & O_EXCL) {
256 if (O_RDONLY == (flags & O_ACCMODE)) {
257 retval = -EPERM; /* Can't lock it with read only access */
258 goto error_out;
260 if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
261 retval = -EBUSY;
262 goto error_out;
264 res = 0;
265 __wait_event_interruptible(sdp->o_excl_wait,
266 ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
267 if (res) {
268 retval = res; /* -ERESTARTSYS because signal hit process */
269 goto error_out;
271 } else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */
272 if (flags & O_NONBLOCK) {
273 retval = -EBUSY;
274 goto error_out;
276 res = 0;
277 __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
278 res);
279 if (res) {
280 retval = res; /* -ERESTARTSYS because signal hit process */
281 goto error_out;
284 if (sdp->detached) {
285 retval = -ENODEV;
286 goto error_out;
288 if (list_empty(&sdp->sfds)) { /* no existing opens on this device */
289 sdp->sgdebug = 0;
290 q = sdp->device->request_queue;
291 sdp->sg_tablesize = queue_max_segments(q);
293 if ((sfp = sg_add_sfp(sdp, dev)))
294 filp->private_data = sfp;
295 else {
296 if (flags & O_EXCL) {
297 sdp->exclude = 0; /* undo if error */
298 wake_up_interruptible(&sdp->o_excl_wait);
300 retval = -ENOMEM;
301 goto error_out;
303 retval = 0;
304 error_out:
305 if (retval)
306 scsi_device_put(sdp->device);
307 sg_put:
308 if (sdp)
309 sg_put_dev(sdp);
310 unlock_kernel();
311 return retval;
314 /* Following function was formerly called 'sg_close' */
315 static int
316 sg_release(struct inode *inode, struct file *filp)
318 Sg_device *sdp;
319 Sg_fd *sfp;
321 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
322 return -ENXIO;
323 SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
325 sfp->closed = 1;
327 sdp->exclude = 0;
328 wake_up_interruptible(&sdp->o_excl_wait);
330 kref_put(&sfp->f_ref, sg_remove_sfp);
331 return 0;
334 static ssize_t
335 sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
337 Sg_device *sdp;
338 Sg_fd *sfp;
339 Sg_request *srp;
340 int req_pack_id = -1;
341 sg_io_hdr_t *hp;
342 struct sg_header *old_hdr = NULL;
343 int retval = 0;
345 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
346 return -ENXIO;
347 SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
348 sdp->disk->disk_name, (int) count));
350 if (!access_ok(VERIFY_WRITE, buf, count))
351 return -EFAULT;
352 if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
353 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
354 if (!old_hdr)
355 return -ENOMEM;
356 if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
357 retval = -EFAULT;
358 goto free_old_hdr;
360 if (old_hdr->reply_len < 0) {
361 if (count >= SZ_SG_IO_HDR) {
362 sg_io_hdr_t *new_hdr;
363 new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
364 if (!new_hdr) {
365 retval = -ENOMEM;
366 goto free_old_hdr;
368 retval =__copy_from_user
369 (new_hdr, buf, SZ_SG_IO_HDR);
370 req_pack_id = new_hdr->pack_id;
371 kfree(new_hdr);
372 if (retval) {
373 retval = -EFAULT;
374 goto free_old_hdr;
377 } else
378 req_pack_id = old_hdr->pack_id;
380 srp = sg_get_rq_mark(sfp, req_pack_id);
381 if (!srp) { /* now wait on packet to arrive */
382 if (sdp->detached) {
383 retval = -ENODEV;
384 goto free_old_hdr;
386 if (filp->f_flags & O_NONBLOCK) {
387 retval = -EAGAIN;
388 goto free_old_hdr;
390 while (1) {
391 retval = 0; /* following macro beats race condition */
392 __wait_event_interruptible(sfp->read_wait,
393 (sdp->detached ||
394 (srp = sg_get_rq_mark(sfp, req_pack_id))),
395 retval);
396 if (sdp->detached) {
397 retval = -ENODEV;
398 goto free_old_hdr;
400 if (0 == retval)
401 break;
403 /* -ERESTARTSYS as signal hit process */
404 goto free_old_hdr;
407 if (srp->header.interface_id != '\0') {
408 retval = sg_new_read(sfp, buf, count, srp);
409 goto free_old_hdr;
412 hp = &srp->header;
413 if (old_hdr == NULL) {
414 old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
415 if (! old_hdr) {
416 retval = -ENOMEM;
417 goto free_old_hdr;
420 memset(old_hdr, 0, SZ_SG_HEADER);
421 old_hdr->reply_len = (int) hp->timeout;
422 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
423 old_hdr->pack_id = hp->pack_id;
424 old_hdr->twelve_byte =
425 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
426 old_hdr->target_status = hp->masked_status;
427 old_hdr->host_status = hp->host_status;
428 old_hdr->driver_status = hp->driver_status;
429 if ((CHECK_CONDITION & hp->masked_status) ||
430 (DRIVER_SENSE & hp->driver_status))
431 memcpy(old_hdr->sense_buffer, srp->sense_b,
432 sizeof (old_hdr->sense_buffer));
433 switch (hp->host_status) {
434 /* This setup of 'result' is for backward compatibility and is best
435 ignored by the user who should use target, host + driver status */
436 case DID_OK:
437 case DID_PASSTHROUGH:
438 case DID_SOFT_ERROR:
439 old_hdr->result = 0;
440 break;
441 case DID_NO_CONNECT:
442 case DID_BUS_BUSY:
443 case DID_TIME_OUT:
444 old_hdr->result = EBUSY;
445 break;
446 case DID_BAD_TARGET:
447 case DID_ABORT:
448 case DID_PARITY:
449 case DID_RESET:
450 case DID_BAD_INTR:
451 old_hdr->result = EIO;
452 break;
453 case DID_ERROR:
454 old_hdr->result = (srp->sense_b[0] == 0 &&
455 hp->masked_status == GOOD) ? 0 : EIO;
456 break;
457 default:
458 old_hdr->result = EIO;
459 break;
462 /* Now copy the result back to the user buffer. */
463 if (count >= SZ_SG_HEADER) {
464 if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
465 retval = -EFAULT;
466 goto free_old_hdr;
468 buf += SZ_SG_HEADER;
469 if (count > old_hdr->reply_len)
470 count = old_hdr->reply_len;
471 if (count > SZ_SG_HEADER) {
472 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
473 retval = -EFAULT;
474 goto free_old_hdr;
477 } else
478 count = (old_hdr->result == 0) ? 0 : -EIO;
479 sg_finish_rem_req(srp);
480 retval = count;
481 free_old_hdr:
482 kfree(old_hdr);
483 return retval;
486 static ssize_t
487 sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
489 sg_io_hdr_t *hp = &srp->header;
490 int err = 0;
491 int len;
493 if (count < SZ_SG_IO_HDR) {
494 err = -EINVAL;
495 goto err_out;
497 hp->sb_len_wr = 0;
498 if ((hp->mx_sb_len > 0) && hp->sbp) {
499 if ((CHECK_CONDITION & hp->masked_status) ||
500 (DRIVER_SENSE & hp->driver_status)) {
501 int sb_len = SCSI_SENSE_BUFFERSIZE;
502 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
503 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */
504 len = (len > sb_len) ? sb_len : len;
505 if (copy_to_user(hp->sbp, srp->sense_b, len)) {
506 err = -EFAULT;
507 goto err_out;
509 hp->sb_len_wr = len;
512 if (hp->masked_status || hp->host_status || hp->driver_status)
513 hp->info |= SG_INFO_CHECK;
514 if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
515 err = -EFAULT;
516 goto err_out;
518 err_out:
519 err = sg_finish_rem_req(srp);
520 return (0 == err) ? count : err;
523 static ssize_t
524 sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
526 int mxsize, cmd_size, k;
527 int input_size, blocking;
528 unsigned char opcode;
529 Sg_device *sdp;
530 Sg_fd *sfp;
531 Sg_request *srp;
532 struct sg_header old_hdr;
533 sg_io_hdr_t *hp;
534 unsigned char cmnd[MAX_COMMAND_SIZE];
536 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
537 return -ENXIO;
538 SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
539 sdp->disk->disk_name, (int) count));
540 if (sdp->detached)
541 return -ENODEV;
542 if (!((filp->f_flags & O_NONBLOCK) ||
543 scsi_block_when_processing_errors(sdp->device)))
544 return -ENXIO;
546 if (!access_ok(VERIFY_READ, buf, count))
547 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
548 if (count < SZ_SG_HEADER)
549 return -EIO;
550 if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
551 return -EFAULT;
552 blocking = !(filp->f_flags & O_NONBLOCK);
553 if (old_hdr.reply_len < 0)
554 return sg_new_write(sfp, filp, buf, count,
555 blocking, 0, 0, NULL);
556 if (count < (SZ_SG_HEADER + 6))
557 return -EIO; /* The minimum scsi command length is 6 bytes. */
559 if (!(srp = sg_add_request(sfp))) {
560 SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
561 return -EDOM;
563 buf += SZ_SG_HEADER;
564 __get_user(opcode, buf);
565 if (sfp->next_cmd_len > 0) {
566 if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
567 SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
568 sfp->next_cmd_len = 0;
569 sg_remove_request(sfp, srp);
570 return -EIO;
572 cmd_size = sfp->next_cmd_len;
573 sfp->next_cmd_len = 0; /* reset so only this write() effected */
574 } else {
575 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
576 if ((opcode >= 0xc0) && old_hdr.twelve_byte)
577 cmd_size = 12;
579 SCSI_LOG_TIMEOUT(4, printk(
580 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
581 /* Determine buffer size. */
582 input_size = count - cmd_size;
583 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
584 mxsize -= SZ_SG_HEADER;
585 input_size -= SZ_SG_HEADER;
586 if (input_size < 0) {
587 sg_remove_request(sfp, srp);
588 return -EIO; /* User did not pass enough bytes for this command. */
590 hp = &srp->header;
591 hp->interface_id = '\0'; /* indicator of old interface tunnelled */
592 hp->cmd_len = (unsigned char) cmd_size;
593 hp->iovec_count = 0;
594 hp->mx_sb_len = 0;
595 if (input_size > 0)
596 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
597 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
598 else
599 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
600 hp->dxfer_len = mxsize;
601 if (hp->dxfer_direction == SG_DXFER_TO_DEV)
602 hp->dxferp = (char __user *)buf + cmd_size;
603 else
604 hp->dxferp = NULL;
605 hp->sbp = NULL;
606 hp->timeout = old_hdr.reply_len; /* structure abuse ... */
607 hp->flags = input_size; /* structure abuse ... */
608 hp->pack_id = old_hdr.pack_id;
609 hp->usr_ptr = NULL;
610 if (__copy_from_user(cmnd, buf, cmd_size))
611 return -EFAULT;
613 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
614 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
615 * is a non-zero input_size, so emit a warning.
617 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
618 static char cmd[TASK_COMM_LEN];
619 if (strcmp(current->comm, cmd) && printk_ratelimit()) {
620 printk(KERN_WARNING
621 "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
622 "guessing data in;\n "
623 "program %s not setting count and/or reply_len properly\n",
624 old_hdr.reply_len - (int)SZ_SG_HEADER,
625 input_size, (unsigned int) cmnd[0],
626 current->comm);
627 strcpy(cmd, current->comm);
630 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
631 return (k < 0) ? k : count;
634 static ssize_t
635 sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
636 size_t count, int blocking, int read_only, int sg_io_owned,
637 Sg_request **o_srp)
639 int k;
640 Sg_request *srp;
641 sg_io_hdr_t *hp;
642 unsigned char cmnd[MAX_COMMAND_SIZE];
643 int timeout;
644 unsigned long ul_timeout;
646 if (count < SZ_SG_IO_HDR)
647 return -EINVAL;
648 if (!access_ok(VERIFY_READ, buf, count))
649 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
651 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */
652 if (!(srp = sg_add_request(sfp))) {
653 SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
654 return -EDOM;
656 srp->sg_io_owned = sg_io_owned;
657 hp = &srp->header;
658 if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
659 sg_remove_request(sfp, srp);
660 return -EFAULT;
662 if (hp->interface_id != 'S') {
663 sg_remove_request(sfp, srp);
664 return -ENOSYS;
666 if (hp->flags & SG_FLAG_MMAP_IO) {
667 if (hp->dxfer_len > sfp->reserve.bufflen) {
668 sg_remove_request(sfp, srp);
669 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */
671 if (hp->flags & SG_FLAG_DIRECT_IO) {
672 sg_remove_request(sfp, srp);
673 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */
675 if (sg_res_in_use(sfp)) {
676 sg_remove_request(sfp, srp);
677 return -EBUSY; /* reserve buffer already being used */
680 ul_timeout = msecs_to_jiffies(srp->header.timeout);
681 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
682 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
683 sg_remove_request(sfp, srp);
684 return -EMSGSIZE;
686 if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
687 sg_remove_request(sfp, srp);
688 return -EFAULT; /* protects following copy_from_user()s + get_user()s */
690 if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
691 sg_remove_request(sfp, srp);
692 return -EFAULT;
694 if (read_only && sg_allow_access(file, cmnd)) {
695 sg_remove_request(sfp, srp);
696 return -EPERM;
698 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
699 if (k < 0)
700 return k;
701 if (o_srp)
702 *o_srp = srp;
703 return count;
706 static int
707 sg_common_write(Sg_fd * sfp, Sg_request * srp,
708 unsigned char *cmnd, int timeout, int blocking)
710 int k, data_dir;
711 Sg_device *sdp = sfp->parentdp;
712 sg_io_hdr_t *hp = &srp->header;
714 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */
715 hp->status = 0;
716 hp->masked_status = 0;
717 hp->msg_status = 0;
718 hp->info = 0;
719 hp->host_status = 0;
720 hp->driver_status = 0;
721 hp->resid = 0;
722 SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",
723 (int) cmnd[0], (int) hp->cmd_len));
725 k = sg_start_req(srp, cmnd);
726 if (k) {
727 SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
728 sg_finish_rem_req(srp);
729 return k; /* probably out of space --> ENOMEM */
731 if (sdp->detached) {
732 sg_finish_rem_req(srp);
733 return -ENODEV;
736 switch (hp->dxfer_direction) {
737 case SG_DXFER_TO_FROM_DEV:
738 case SG_DXFER_FROM_DEV:
739 data_dir = DMA_FROM_DEVICE;
740 break;
741 case SG_DXFER_TO_DEV:
742 data_dir = DMA_TO_DEVICE;
743 break;
744 case SG_DXFER_UNKNOWN:
745 data_dir = DMA_BIDIRECTIONAL;
746 break;
747 default:
748 data_dir = DMA_NONE;
749 break;
751 hp->duration = jiffies_to_msecs(jiffies);
753 srp->rq->timeout = timeout;
754 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
755 blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
756 srp->rq, 1, sg_rq_end_io);
757 return 0;
760 static int
761 sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
763 void __user *p = (void __user *)arg;
764 int __user *ip = p;
765 int result, val, read_only;
766 Sg_device *sdp;
767 Sg_fd *sfp;
768 Sg_request *srp;
769 unsigned long iflags;
771 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
772 return -ENXIO;
774 SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
775 sdp->disk->disk_name, (int) cmd_in));
776 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
778 switch (cmd_in) {
779 case SG_IO:
781 int blocking = 1; /* ignore O_NONBLOCK flag */
783 if (sdp->detached)
784 return -ENODEV;
785 if (!scsi_block_when_processing_errors(sdp->device))
786 return -ENXIO;
787 if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
788 return -EFAULT;
789 result =
790 sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
791 blocking, read_only, 1, &srp);
792 if (result < 0)
793 return result;
794 while (1) {
795 result = 0; /* following macro to beat race condition */
796 __wait_event_interruptible(sfp->read_wait,
797 (srp->done || sdp->detached),
798 result);
799 if (sdp->detached)
800 return -ENODEV;
801 write_lock_irq(&sfp->rq_list_lock);
802 if (srp->done) {
803 srp->done = 2;
804 write_unlock_irq(&sfp->rq_list_lock);
805 break;
807 srp->orphan = 1;
808 write_unlock_irq(&sfp->rq_list_lock);
809 return result; /* -ERESTARTSYS because signal hit process */
811 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
812 return (result < 0) ? result : 0;
814 case SG_SET_TIMEOUT:
815 result = get_user(val, ip);
816 if (result)
817 return result;
818 if (val < 0)
819 return -EIO;
820 if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
821 val = MULDIV (INT_MAX, USER_HZ, HZ);
822 sfp->timeout_user = val;
823 sfp->timeout = MULDIV (val, HZ, USER_HZ);
825 return 0;
826 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
827 /* strange ..., for backward compatibility */
828 return sfp->timeout_user;
829 case SG_SET_FORCE_LOW_DMA:
830 result = get_user(val, ip);
831 if (result)
832 return result;
833 if (val) {
834 sfp->low_dma = 1;
835 if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
836 val = (int) sfp->reserve.bufflen;
837 sg_remove_scat(&sfp->reserve);
838 sg_build_reserve(sfp, val);
840 } else {
841 if (sdp->detached)
842 return -ENODEV;
843 sfp->low_dma = sdp->device->host->unchecked_isa_dma;
845 return 0;
846 case SG_GET_LOW_DMA:
847 return put_user((int) sfp->low_dma, ip);
848 case SG_GET_SCSI_ID:
849 if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
850 return -EFAULT;
851 else {
852 sg_scsi_id_t __user *sg_idp = p;
854 if (sdp->detached)
855 return -ENODEV;
856 __put_user((int) sdp->device->host->host_no,
857 &sg_idp->host_no);
858 __put_user((int) sdp->device->channel,
859 &sg_idp->channel);
860 __put_user((int) sdp->device->id, &sg_idp->scsi_id);
861 __put_user((int) sdp->device->lun, &sg_idp->lun);
862 __put_user((int) sdp->device->type, &sg_idp->scsi_type);
863 __put_user((short) sdp->device->host->cmd_per_lun,
864 &sg_idp->h_cmd_per_lun);
865 __put_user((short) sdp->device->queue_depth,
866 &sg_idp->d_queue_depth);
867 __put_user(0, &sg_idp->unused[0]);
868 __put_user(0, &sg_idp->unused[1]);
869 return 0;
871 case SG_SET_FORCE_PACK_ID:
872 result = get_user(val, ip);
873 if (result)
874 return result;
875 sfp->force_packid = val ? 1 : 0;
876 return 0;
877 case SG_GET_PACK_ID:
878 if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
879 return -EFAULT;
880 read_lock_irqsave(&sfp->rq_list_lock, iflags);
881 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
882 if ((1 == srp->done) && (!srp->sg_io_owned)) {
883 read_unlock_irqrestore(&sfp->rq_list_lock,
884 iflags);
885 __put_user(srp->header.pack_id, ip);
886 return 0;
889 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
890 __put_user(-1, ip);
891 return 0;
892 case SG_GET_NUM_WAITING:
893 read_lock_irqsave(&sfp->rq_list_lock, iflags);
894 for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
895 if ((1 == srp->done) && (!srp->sg_io_owned))
896 ++val;
898 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
899 return put_user(val, ip);
900 case SG_GET_SG_TABLESIZE:
901 return put_user(sdp->sg_tablesize, ip);
902 case SG_SET_RESERVED_SIZE:
903 result = get_user(val, ip);
904 if (result)
905 return result;
906 if (val < 0)
907 return -EINVAL;
908 val = min_t(int, val,
909 queue_max_sectors(sdp->device->request_queue) * 512);
910 if (val != sfp->reserve.bufflen) {
911 if (sg_res_in_use(sfp) || sfp->mmap_called)
912 return -EBUSY;
913 sg_remove_scat(&sfp->reserve);
914 sg_build_reserve(sfp, val);
916 return 0;
917 case SG_GET_RESERVED_SIZE:
918 val = min_t(int, sfp->reserve.bufflen,
919 queue_max_sectors(sdp->device->request_queue) * 512);
920 return put_user(val, ip);
921 case SG_SET_COMMAND_Q:
922 result = get_user(val, ip);
923 if (result)
924 return result;
925 sfp->cmd_q = val ? 1 : 0;
926 return 0;
927 case SG_GET_COMMAND_Q:
928 return put_user((int) sfp->cmd_q, ip);
929 case SG_SET_KEEP_ORPHAN:
930 result = get_user(val, ip);
931 if (result)
932 return result;
933 sfp->keep_orphan = val;
934 return 0;
935 case SG_GET_KEEP_ORPHAN:
936 return put_user((int) sfp->keep_orphan, ip);
937 case SG_NEXT_CMD_LEN:
938 result = get_user(val, ip);
939 if (result)
940 return result;
941 sfp->next_cmd_len = (val > 0) ? val : 0;
942 return 0;
943 case SG_GET_VERSION_NUM:
944 return put_user(sg_version_num, ip);
945 case SG_GET_ACCESS_COUNT:
946 /* faked - we don't have a real access count anymore */
947 val = (sdp->device ? 1 : 0);
948 return put_user(val, ip);
949 case SG_GET_REQUEST_TABLE:
950 if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
951 return -EFAULT;
952 else {
953 sg_req_info_t *rinfo;
954 unsigned int ms;
956 rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
957 GFP_KERNEL);
958 if (!rinfo)
959 return -ENOMEM;
960 read_lock_irqsave(&sfp->rq_list_lock, iflags);
961 for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
962 ++val, srp = srp ? srp->nextrp : srp) {
963 memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
964 if (srp) {
965 rinfo[val].req_state = srp->done + 1;
966 rinfo[val].problem =
967 srp->header.masked_status &
968 srp->header.host_status &
969 srp->header.driver_status;
970 if (srp->done)
971 rinfo[val].duration =
972 srp->header.duration;
973 else {
974 ms = jiffies_to_msecs(jiffies);
975 rinfo[val].duration =
976 (ms > srp->header.duration) ?
977 (ms - srp->header.duration) : 0;
979 rinfo[val].orphan = srp->orphan;
980 rinfo[val].sg_io_owned =
981 srp->sg_io_owned;
982 rinfo[val].pack_id =
983 srp->header.pack_id;
984 rinfo[val].usr_ptr =
985 srp->header.usr_ptr;
988 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
989 result = __copy_to_user(p, rinfo,
990 SZ_SG_REQ_INFO * SG_MAX_QUEUE);
991 result = result ? -EFAULT : 0;
992 kfree(rinfo);
993 return result;
995 case SG_EMULATED_HOST:
996 if (sdp->detached)
997 return -ENODEV;
998 return put_user(sdp->device->host->hostt->emulated, ip);
999 case SG_SCSI_RESET:
1000 if (sdp->detached)
1001 return -ENODEV;
1002 if (filp->f_flags & O_NONBLOCK) {
1003 if (scsi_host_in_recovery(sdp->device->host))
1004 return -EBUSY;
1005 } else if (!scsi_block_when_processing_errors(sdp->device))
1006 return -EBUSY;
1007 result = get_user(val, ip);
1008 if (result)
1009 return result;
1010 if (SG_SCSI_RESET_NOTHING == val)
1011 return 0;
1012 switch (val) {
1013 case SG_SCSI_RESET_DEVICE:
1014 val = SCSI_TRY_RESET_DEVICE;
1015 break;
1016 case SG_SCSI_RESET_TARGET:
1017 val = SCSI_TRY_RESET_TARGET;
1018 break;
1019 case SG_SCSI_RESET_BUS:
1020 val = SCSI_TRY_RESET_BUS;
1021 break;
1022 case SG_SCSI_RESET_HOST:
1023 val = SCSI_TRY_RESET_HOST;
1024 break;
1025 default:
1026 return -EINVAL;
1028 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1029 return -EACCES;
1030 return (scsi_reset_provider(sdp->device, val) ==
1031 SUCCESS) ? 0 : -EIO;
1032 case SCSI_IOCTL_SEND_COMMAND:
1033 if (sdp->detached)
1034 return -ENODEV;
1035 if (read_only) {
1036 unsigned char opcode = WRITE_6;
1037 Scsi_Ioctl_Command __user *siocp = p;
1039 if (copy_from_user(&opcode, siocp->data, 1))
1040 return -EFAULT;
1041 if (sg_allow_access(filp, &opcode))
1042 return -EPERM;
1044 return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1045 case SG_SET_DEBUG:
1046 result = get_user(val, ip);
1047 if (result)
1048 return result;
1049 sdp->sgdebug = (char) val;
1050 return 0;
1051 case SCSI_IOCTL_GET_IDLUN:
1052 case SCSI_IOCTL_GET_BUS_NUMBER:
1053 case SCSI_IOCTL_PROBE_HOST:
1054 case SG_GET_TRANSFORM:
1055 if (sdp->detached)
1056 return -ENODEV;
1057 return scsi_ioctl(sdp->device, cmd_in, p);
1058 case BLKSECTGET:
1059 return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1060 ip);
1061 case BLKTRACESETUP:
1062 return blk_trace_setup(sdp->device->request_queue,
1063 sdp->disk->disk_name,
1064 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1065 NULL,
1066 (char *)arg);
1067 case BLKTRACESTART:
1068 return blk_trace_startstop(sdp->device->request_queue, 1);
1069 case BLKTRACESTOP:
1070 return blk_trace_startstop(sdp->device->request_queue, 0);
1071 case BLKTRACETEARDOWN:
1072 return blk_trace_remove(sdp->device->request_queue);
1073 default:
1074 if (read_only)
1075 return -EPERM; /* don't know so take safe approach */
1076 return scsi_ioctl(sdp->device, cmd_in, p);
1080 static long
1081 sg_unlocked_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1083 int ret;
1085 lock_kernel();
1086 ret = sg_ioctl(filp, cmd_in, arg);
1087 unlock_kernel();
1089 return ret;
1092 #ifdef CONFIG_COMPAT
1093 static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1095 Sg_device *sdp;
1096 Sg_fd *sfp;
1097 struct scsi_device *sdev;
1099 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1100 return -ENXIO;
1102 sdev = sdp->device;
1103 if (sdev->host->hostt->compat_ioctl) {
1104 int ret;
1106 ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1108 return ret;
1111 return -ENOIOCTLCMD;
1113 #endif
1115 static unsigned int
1116 sg_poll(struct file *filp, poll_table * wait)
1118 unsigned int res = 0;
1119 Sg_device *sdp;
1120 Sg_fd *sfp;
1121 Sg_request *srp;
1122 int count = 0;
1123 unsigned long iflags;
1125 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1126 || sfp->closed)
1127 return POLLERR;
1128 poll_wait(filp, &sfp->read_wait, wait);
1129 read_lock_irqsave(&sfp->rq_list_lock, iflags);
1130 for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1131 /* if any read waiting, flag it */
1132 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1133 res = POLLIN | POLLRDNORM;
1134 ++count;
1136 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1138 if (sdp->detached)
1139 res |= POLLHUP;
1140 else if (!sfp->cmd_q) {
1141 if (0 == count)
1142 res |= POLLOUT | POLLWRNORM;
1143 } else if (count < SG_MAX_QUEUE)
1144 res |= POLLOUT | POLLWRNORM;
1145 SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1146 sdp->disk->disk_name, (int) res));
1147 return res;
1150 static int
1151 sg_fasync(int fd, struct file *filp, int mode)
1153 Sg_device *sdp;
1154 Sg_fd *sfp;
1156 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1157 return -ENXIO;
1158 SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1159 sdp->disk->disk_name, mode));
1161 return fasync_helper(fd, filp, mode, &sfp->async_qp);
1164 static int
1165 sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1167 Sg_fd *sfp;
1168 unsigned long offset, len, sa;
1169 Sg_scatter_hold *rsv_schp;
1170 int k, length;
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 sa = vma->vm_start;
1181 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1182 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1183 len = vma->vm_end - sa;
1184 len = (len < length) ? len : length;
1185 if (offset < len) {
1186 struct page *page = nth_page(rsv_schp->pages[k],
1187 offset >> PAGE_SHIFT);
1188 get_page(page); /* increment page count */
1189 vmf->page = page;
1190 return 0; /* success */
1192 sa += len;
1193 offset -= len;
1196 return VM_FAULT_SIGBUS;
1199 static const struct vm_operations_struct sg_mmap_vm_ops = {
1200 .fault = sg_vma_fault,
1203 static int
1204 sg_mmap(struct file *filp, struct vm_area_struct *vma)
1206 Sg_fd *sfp;
1207 unsigned long req_sz, len, sa;
1208 Sg_scatter_hold *rsv_schp;
1209 int k, length;
1211 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1212 return -ENXIO;
1213 req_sz = vma->vm_end - vma->vm_start;
1214 SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n",
1215 (void *) vma->vm_start, (int) req_sz));
1216 if (vma->vm_pgoff)
1217 return -EINVAL; /* want no offset */
1218 rsv_schp = &sfp->reserve;
1219 if (req_sz > rsv_schp->bufflen)
1220 return -ENOMEM; /* cannot map more than reserved buffer */
1222 sa = vma->vm_start;
1223 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1224 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1225 len = vma->vm_end - sa;
1226 len = (len < length) ? len : length;
1227 sa += len;
1230 sfp->mmap_called = 1;
1231 vma->vm_flags |= VM_RESERVED;
1232 vma->vm_private_data = sfp;
1233 vma->vm_ops = &sg_mmap_vm_ops;
1234 return 0;
1237 static void sg_rq_end_io_usercontext(struct work_struct *work)
1239 struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1240 struct sg_fd *sfp = srp->parentfp;
1242 sg_finish_rem_req(srp);
1243 kref_put(&sfp->f_ref, sg_remove_sfp);
1247 * This function is a "bottom half" handler that is called by the mid
1248 * level when a command is completed (or has failed).
1250 static void sg_rq_end_io(struct request *rq, int uptodate)
1252 struct sg_request *srp = rq->end_io_data;
1253 Sg_device *sdp;
1254 Sg_fd *sfp;
1255 unsigned long iflags;
1256 unsigned int ms;
1257 char *sense;
1258 int result, resid, done = 1;
1260 if (WARN_ON(srp->done != 0))
1261 return;
1263 sfp = srp->parentfp;
1264 if (WARN_ON(sfp == NULL))
1265 return;
1267 sdp = sfp->parentdp;
1268 if (unlikely(sdp->detached))
1269 printk(KERN_INFO "sg_rq_end_io: device detached\n");
1271 sense = rq->sense;
1272 result = rq->errors;
1273 resid = rq->resid_len;
1275 SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1276 sdp->disk->disk_name, srp->header.pack_id, result));
1277 srp->header.resid = resid;
1278 ms = jiffies_to_msecs(jiffies);
1279 srp->header.duration = (ms > srp->header.duration) ?
1280 (ms - srp->header.duration) : 0;
1281 if (0 != result) {
1282 struct scsi_sense_hdr sshdr;
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);
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;
1306 /* Rely on write phase to clean out srp status values, so no "else" */
1308 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1309 if (unlikely(srp->orphan)) {
1310 if (sfp->keep_orphan)
1311 srp->sg_io_owned = 0;
1312 else
1313 done = 0;
1315 srp->done = done;
1316 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1318 if (likely(done)) {
1319 /* Now wake up any sg_read() that is waiting for this
1320 * packet.
1322 wake_up_interruptible(&sfp->read_wait);
1323 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1324 kref_put(&sfp->f_ref, sg_remove_sfp);
1325 } else {
1326 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1327 schedule_work(&srp->ew.work);
1331 static const struct file_operations sg_fops = {
1332 .owner = THIS_MODULE,
1333 .read = sg_read,
1334 .write = sg_write,
1335 .poll = sg_poll,
1336 .unlocked_ioctl = sg_unlocked_ioctl,
1337 #ifdef CONFIG_COMPAT
1338 .compat_ioctl = sg_compat_ioctl,
1339 #endif
1340 .open = sg_open,
1341 .mmap = sg_mmap,
1342 .release = sg_release,
1343 .fasync = sg_fasync,
1346 static struct class *sg_sysfs_class;
1348 static int sg_sysfs_valid = 0;
1350 static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1352 struct request_queue *q = scsidp->request_queue;
1353 Sg_device *sdp;
1354 unsigned long iflags;
1355 int error;
1356 u32 k;
1358 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1359 if (!sdp) {
1360 printk(KERN_WARNING "kmalloc Sg_device failure\n");
1361 return ERR_PTR(-ENOMEM);
1364 if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1365 printk(KERN_WARNING "idr expansion Sg_device failure\n");
1366 error = -ENOMEM;
1367 goto out;
1370 write_lock_irqsave(&sg_index_lock, iflags);
1372 error = idr_get_new(&sg_index_idr, sdp, &k);
1373 if (error) {
1374 write_unlock_irqrestore(&sg_index_lock, iflags);
1375 printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1376 error);
1377 goto out;
1380 if (unlikely(k >= SG_MAX_DEVS))
1381 goto overflow;
1383 SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1384 sprintf(disk->disk_name, "sg%d", k);
1385 disk->first_minor = k;
1386 sdp->disk = disk;
1387 sdp->device = scsidp;
1388 INIT_LIST_HEAD(&sdp->sfds);
1389 init_waitqueue_head(&sdp->o_excl_wait);
1390 sdp->sg_tablesize = queue_max_segments(q);
1391 sdp->index = k;
1392 kref_init(&sdp->d_ref);
1394 write_unlock_irqrestore(&sg_index_lock, iflags);
1396 error = 0;
1397 out:
1398 if (error) {
1399 kfree(sdp);
1400 return ERR_PTR(error);
1402 return sdp;
1404 overflow:
1405 idr_remove(&sg_index_idr, k);
1406 write_unlock_irqrestore(&sg_index_lock, iflags);
1407 sdev_printk(KERN_WARNING, scsidp,
1408 "Unable to attach sg device type=%d, minor "
1409 "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1410 error = -ENODEV;
1411 goto out;
1414 static int
1415 sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1417 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1418 struct gendisk *disk;
1419 Sg_device *sdp = NULL;
1420 struct cdev * cdev = NULL;
1421 int error;
1422 unsigned long iflags;
1424 disk = alloc_disk(1);
1425 if (!disk) {
1426 printk(KERN_WARNING "alloc_disk failed\n");
1427 return -ENOMEM;
1429 disk->major = SCSI_GENERIC_MAJOR;
1431 error = -ENOMEM;
1432 cdev = cdev_alloc();
1433 if (!cdev) {
1434 printk(KERN_WARNING "cdev_alloc failed\n");
1435 goto out;
1437 cdev->owner = THIS_MODULE;
1438 cdev->ops = &sg_fops;
1440 sdp = sg_alloc(disk, scsidp);
1441 if (IS_ERR(sdp)) {
1442 printk(KERN_WARNING "sg_alloc failed\n");
1443 error = PTR_ERR(sdp);
1444 goto out;
1447 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1448 if (error)
1449 goto cdev_add_err;
1451 sdp->cdev = cdev;
1452 if (sg_sysfs_valid) {
1453 struct device *sg_class_member;
1455 sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1456 MKDEV(SCSI_GENERIC_MAJOR,
1457 sdp->index),
1458 sdp, "%s", disk->disk_name);
1459 if (IS_ERR(sg_class_member)) {
1460 printk(KERN_ERR "sg_add: "
1461 "device_create failed\n");
1462 error = PTR_ERR(sg_class_member);
1463 goto cdev_add_err;
1465 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1466 &sg_class_member->kobj, "generic");
1467 if (error)
1468 printk(KERN_ERR "sg_add: unable to make symlink "
1469 "'generic' back to sg%d\n", sdp->index);
1470 } else
1471 printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1473 sdev_printk(KERN_NOTICE, scsidp,
1474 "Attached scsi generic sg%d type %d\n", sdp->index,
1475 scsidp->type);
1477 dev_set_drvdata(cl_dev, sdp);
1479 return 0;
1481 cdev_add_err:
1482 write_lock_irqsave(&sg_index_lock, iflags);
1483 idr_remove(&sg_index_idr, sdp->index);
1484 write_unlock_irqrestore(&sg_index_lock, iflags);
1485 kfree(sdp);
1487 out:
1488 put_disk(disk);
1489 if (cdev)
1490 cdev_del(cdev);
1491 return error;
1494 static void sg_device_destroy(struct kref *kref)
1496 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1497 unsigned long flags;
1499 /* CAUTION! Note that the device can still be found via idr_find()
1500 * even though the refcount is 0. Therefore, do idr_remove() BEFORE
1501 * any other cleanup.
1504 write_lock_irqsave(&sg_index_lock, flags);
1505 idr_remove(&sg_index_idr, sdp->index);
1506 write_unlock_irqrestore(&sg_index_lock, flags);
1508 SCSI_LOG_TIMEOUT(3,
1509 printk("sg_device_destroy: %s\n",
1510 sdp->disk->disk_name));
1512 put_disk(sdp->disk);
1513 kfree(sdp);
1516 static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
1518 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1519 Sg_device *sdp = dev_get_drvdata(cl_dev);
1520 unsigned long iflags;
1521 Sg_fd *sfp;
1523 if (!sdp || sdp->detached)
1524 return;
1526 SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
1528 /* Need a write lock to set sdp->detached. */
1529 write_lock_irqsave(&sg_index_lock, iflags);
1530 sdp->detached = 1;
1531 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1532 wake_up_interruptible(&sfp->read_wait);
1533 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1535 write_unlock_irqrestore(&sg_index_lock, iflags);
1537 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1538 device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1539 cdev_del(sdp->cdev);
1540 sdp->cdev = NULL;
1542 sg_put_dev(sdp);
1545 module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1546 module_param_named(def_reserved_size, def_reserved_size, int,
1547 S_IRUGO | S_IWUSR);
1548 module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1550 MODULE_AUTHOR("Douglas Gilbert");
1551 MODULE_DESCRIPTION("SCSI generic (sg) driver");
1552 MODULE_LICENSE("GPL");
1553 MODULE_VERSION(SG_VERSION_STR);
1554 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1556 MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1557 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1558 MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1559 MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1561 static int __init
1562 init_sg(void)
1564 int rc;
1566 if (scatter_elem_sz < PAGE_SIZE) {
1567 scatter_elem_sz = PAGE_SIZE;
1568 scatter_elem_sz_prev = scatter_elem_sz;
1570 if (def_reserved_size >= 0)
1571 sg_big_buff = def_reserved_size;
1572 else
1573 def_reserved_size = sg_big_buff;
1575 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1576 SG_MAX_DEVS, "sg");
1577 if (rc)
1578 return rc;
1579 sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1580 if ( IS_ERR(sg_sysfs_class) ) {
1581 rc = PTR_ERR(sg_sysfs_class);
1582 goto err_out;
1584 sg_sysfs_valid = 1;
1585 rc = scsi_register_interface(&sg_interface);
1586 if (0 == rc) {
1587 #ifdef CONFIG_SCSI_PROC_FS
1588 sg_proc_init();
1589 #endif /* CONFIG_SCSI_PROC_FS */
1590 return 0;
1592 class_destroy(sg_sysfs_class);
1593 err_out:
1594 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1595 return rc;
1598 static void __exit
1599 exit_sg(void)
1601 #ifdef CONFIG_SCSI_PROC_FS
1602 sg_proc_cleanup();
1603 #endif /* CONFIG_SCSI_PROC_FS */
1604 scsi_unregister_interface(&sg_interface);
1605 class_destroy(sg_sysfs_class);
1606 sg_sysfs_valid = 0;
1607 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1608 SG_MAX_DEVS);
1609 idr_destroy(&sg_index_idr);
1612 static int sg_start_req(Sg_request *srp, unsigned char *cmd)
1614 int res;
1615 struct request *rq;
1616 Sg_fd *sfp = srp->parentfp;
1617 sg_io_hdr_t *hp = &srp->header;
1618 int dxfer_len = (int) hp->dxfer_len;
1619 int dxfer_dir = hp->dxfer_direction;
1620 unsigned int iov_count = hp->iovec_count;
1621 Sg_scatter_hold *req_schp = &srp->data;
1622 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1623 struct request_queue *q = sfp->parentdp->device->request_queue;
1624 struct rq_map_data *md, map_data;
1625 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1627 SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1628 dxfer_len));
1630 rq = blk_get_request(q, rw, GFP_ATOMIC);
1631 if (!rq)
1632 return -ENOMEM;
1634 memcpy(rq->cmd, cmd, hp->cmd_len);
1636 rq->cmd_len = hp->cmd_len;
1637 rq->cmd_type = REQ_TYPE_BLOCK_PC;
1639 srp->rq = rq;
1640 rq->end_io_data = srp;
1641 rq->sense = srp->sense_b;
1642 rq->retries = SG_DEFAULT_RETRIES;
1644 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1645 return 0;
1647 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1648 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1649 !sfp->parentdp->device->host->unchecked_isa_dma &&
1650 blk_rq_aligned(q, hp->dxferp, dxfer_len))
1651 md = NULL;
1652 else
1653 md = &map_data;
1655 if (md) {
1656 if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1657 sg_link_reserve(sfp, srp, dxfer_len);
1658 else {
1659 res = sg_build_indirect(req_schp, sfp, dxfer_len);
1660 if (res)
1661 return res;
1664 md->pages = req_schp->pages;
1665 md->page_order = req_schp->page_order;
1666 md->nr_entries = req_schp->k_use_sg;
1667 md->offset = 0;
1668 md->null_mapped = hp->dxferp ? 0 : 1;
1669 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1670 md->from_user = 1;
1671 else
1672 md->from_user = 0;
1675 if (iov_count) {
1676 int len, size = sizeof(struct sg_iovec) * iov_count;
1677 struct iovec *iov;
1679 iov = kmalloc(size, GFP_ATOMIC);
1680 if (!iov)
1681 return -ENOMEM;
1683 if (copy_from_user(iov, hp->dxferp, size)) {
1684 kfree(iov);
1685 return -EFAULT;
1688 len = iov_length(iov, iov_count);
1689 if (hp->dxfer_len < len) {
1690 iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1691 len = hp->dxfer_len;
1694 res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1695 iov_count,
1696 len, GFP_ATOMIC);
1697 kfree(iov);
1698 } else
1699 res = blk_rq_map_user(q, rq, md, hp->dxferp,
1700 hp->dxfer_len, GFP_ATOMIC);
1702 if (!res) {
1703 srp->bio = rq->bio;
1705 if (!md) {
1706 req_schp->dio_in_use = 1;
1707 hp->info |= SG_INFO_DIRECT_IO;
1710 return res;
1713 static int sg_finish_rem_req(Sg_request * srp)
1715 int ret = 0;
1717 Sg_fd *sfp = srp->parentfp;
1718 Sg_scatter_hold *req_schp = &srp->data;
1720 SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
1721 if (srp->rq) {
1722 if (srp->bio)
1723 ret = blk_rq_unmap_user(srp->bio);
1725 blk_put_request(srp->rq);
1728 if (srp->res_used)
1729 sg_unlink_reserve(sfp, srp);
1730 else
1731 sg_remove_scat(req_schp);
1733 sg_remove_request(sfp, srp);
1735 return ret;
1738 static int
1739 sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1741 int sg_bufflen = tablesize * sizeof(struct page *);
1742 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1744 schp->pages = kzalloc(sg_bufflen, gfp_flags);
1745 if (!schp->pages)
1746 return -ENOMEM;
1747 schp->sglist_len = sg_bufflen;
1748 return tablesize; /* number of scat_gath elements allocated */
1751 static int
1752 sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1754 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1755 int sg_tablesize = sfp->parentdp->sg_tablesize;
1756 int blk_size = buff_size, order;
1757 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1759 if (blk_size < 0)
1760 return -EFAULT;
1761 if (0 == blk_size)
1762 ++blk_size; /* don't know why */
1763 /* round request up to next highest SG_SECTOR_SZ byte boundary */
1764 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1765 SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1766 buff_size, blk_size));
1768 /* N.B. ret_sz carried into this block ... */
1769 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1770 if (mx_sc_elems < 0)
1771 return mx_sc_elems; /* most likely -ENOMEM */
1773 num = scatter_elem_sz;
1774 if (unlikely(num != scatter_elem_sz_prev)) {
1775 if (num < PAGE_SIZE) {
1776 scatter_elem_sz = PAGE_SIZE;
1777 scatter_elem_sz_prev = PAGE_SIZE;
1778 } else
1779 scatter_elem_sz_prev = num;
1782 if (sfp->low_dma)
1783 gfp_mask |= GFP_DMA;
1785 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1786 gfp_mask |= __GFP_ZERO;
1788 order = get_order(num);
1789 retry:
1790 ret_sz = 1 << (PAGE_SHIFT + order);
1792 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1793 k++, rem_sz -= ret_sz) {
1795 num = (rem_sz > scatter_elem_sz_prev) ?
1796 scatter_elem_sz_prev : rem_sz;
1798 schp->pages[k] = alloc_pages(gfp_mask, order);
1799 if (!schp->pages[k])
1800 goto out;
1802 if (num == scatter_elem_sz_prev) {
1803 if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1804 scatter_elem_sz = ret_sz;
1805 scatter_elem_sz_prev = ret_sz;
1809 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1810 "ret_sz=%d\n", k, num, ret_sz));
1811 } /* end of for loop */
1813 schp->page_order = order;
1814 schp->k_use_sg = k;
1815 SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1816 "rem_sz=%d\n", k, rem_sz));
1818 schp->bufflen = blk_size;
1819 if (rem_sz > 0) /* must have failed */
1820 return -ENOMEM;
1821 return 0;
1822 out:
1823 for (i = 0; i < k; i++)
1824 __free_pages(schp->pages[i], order);
1826 if (--order >= 0)
1827 goto retry;
1829 return -ENOMEM;
1832 static void
1833 sg_remove_scat(Sg_scatter_hold * schp)
1835 SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1836 if (schp->pages && schp->sglist_len > 0) {
1837 if (!schp->dio_in_use) {
1838 int k;
1840 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1841 SCSI_LOG_TIMEOUT(5, printk(
1842 "sg_remove_scat: k=%d, pg=0x%p\n",
1843 k, schp->pages[k]));
1844 __free_pages(schp->pages[k], schp->page_order);
1847 kfree(schp->pages);
1850 memset(schp, 0, sizeof (*schp));
1853 static int
1854 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1856 Sg_scatter_hold *schp = &srp->data;
1857 int k, num;
1859 SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1860 num_read_xfer));
1861 if ((!outp) || (num_read_xfer <= 0))
1862 return 0;
1864 num = 1 << (PAGE_SHIFT + schp->page_order);
1865 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1866 if (num > num_read_xfer) {
1867 if (__copy_to_user(outp, page_address(schp->pages[k]),
1868 num_read_xfer))
1869 return -EFAULT;
1870 break;
1871 } else {
1872 if (__copy_to_user(outp, page_address(schp->pages[k]),
1873 num))
1874 return -EFAULT;
1875 num_read_xfer -= num;
1876 if (num_read_xfer <= 0)
1877 break;
1878 outp += num;
1882 return 0;
1885 static void
1886 sg_build_reserve(Sg_fd * sfp, int req_size)
1888 Sg_scatter_hold *schp = &sfp->reserve;
1890 SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
1891 do {
1892 if (req_size < PAGE_SIZE)
1893 req_size = PAGE_SIZE;
1894 if (0 == sg_build_indirect(schp, sfp, req_size))
1895 return;
1896 else
1897 sg_remove_scat(schp);
1898 req_size >>= 1; /* divide by 2 */
1899 } while (req_size > (PAGE_SIZE / 2));
1902 static void
1903 sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1905 Sg_scatter_hold *req_schp = &srp->data;
1906 Sg_scatter_hold *rsv_schp = &sfp->reserve;
1907 int k, num, rem;
1909 srp->res_used = 1;
1910 SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
1911 rem = size;
1913 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1914 for (k = 0; k < rsv_schp->k_use_sg; k++) {
1915 if (rem <= num) {
1916 req_schp->k_use_sg = k + 1;
1917 req_schp->sglist_len = rsv_schp->sglist_len;
1918 req_schp->pages = rsv_schp->pages;
1920 req_schp->bufflen = size;
1921 req_schp->page_order = rsv_schp->page_order;
1922 break;
1923 } else
1924 rem -= num;
1927 if (k >= rsv_schp->k_use_sg)
1928 SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
1931 static void
1932 sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1934 Sg_scatter_hold *req_schp = &srp->data;
1936 SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1937 (int) req_schp->k_use_sg));
1938 req_schp->k_use_sg = 0;
1939 req_schp->bufflen = 0;
1940 req_schp->pages = NULL;
1941 req_schp->page_order = 0;
1942 req_schp->sglist_len = 0;
1943 sfp->save_scat_len = 0;
1944 srp->res_used = 0;
1947 static Sg_request *
1948 sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1950 Sg_request *resp;
1951 unsigned long iflags;
1953 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1954 for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1955 /* look for requests that are ready + not SG_IO owned */
1956 if ((1 == resp->done) && (!resp->sg_io_owned) &&
1957 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1958 resp->done = 2; /* guard against other readers */
1959 break;
1962 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1963 return resp;
1966 /* always adds to end of list */
1967 static Sg_request *
1968 sg_add_request(Sg_fd * sfp)
1970 int k;
1971 unsigned long iflags;
1972 Sg_request *resp;
1973 Sg_request *rp = sfp->req_arr;
1975 write_lock_irqsave(&sfp->rq_list_lock, iflags);
1976 resp = sfp->headrp;
1977 if (!resp) {
1978 memset(rp, 0, sizeof (Sg_request));
1979 rp->parentfp = sfp;
1980 resp = rp;
1981 sfp->headrp = resp;
1982 } else {
1983 if (0 == sfp->cmd_q)
1984 resp = NULL; /* command queuing disallowed */
1985 else {
1986 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1987 if (!rp->parentfp)
1988 break;
1990 if (k < SG_MAX_QUEUE) {
1991 memset(rp, 0, sizeof (Sg_request));
1992 rp->parentfp = sfp;
1993 while (resp->nextrp)
1994 resp = resp->nextrp;
1995 resp->nextrp = rp;
1996 resp = rp;
1997 } else
1998 resp = NULL;
2001 if (resp) {
2002 resp->nextrp = NULL;
2003 resp->header.duration = jiffies_to_msecs(jiffies);
2005 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2006 return resp;
2009 /* Return of 1 for found; 0 for not found */
2010 static int
2011 sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2013 Sg_request *prev_rp;
2014 Sg_request *rp;
2015 unsigned long iflags;
2016 int res = 0;
2018 if ((!sfp) || (!srp) || (!sfp->headrp))
2019 return res;
2020 write_lock_irqsave(&sfp->rq_list_lock, iflags);
2021 prev_rp = sfp->headrp;
2022 if (srp == prev_rp) {
2023 sfp->headrp = prev_rp->nextrp;
2024 prev_rp->parentfp = NULL;
2025 res = 1;
2026 } else {
2027 while ((rp = prev_rp->nextrp)) {
2028 if (srp == rp) {
2029 prev_rp->nextrp = rp->nextrp;
2030 rp->parentfp = NULL;
2031 res = 1;
2032 break;
2034 prev_rp = rp;
2037 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2038 return res;
2041 static Sg_fd *
2042 sg_add_sfp(Sg_device * sdp, int dev)
2044 Sg_fd *sfp;
2045 unsigned long iflags;
2046 int bufflen;
2048 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2049 if (!sfp)
2050 return NULL;
2052 init_waitqueue_head(&sfp->read_wait);
2053 rwlock_init(&sfp->rq_list_lock);
2055 kref_init(&sfp->f_ref);
2056 sfp->timeout = SG_DEFAULT_TIMEOUT;
2057 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2058 sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2059 sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2060 sdp->device->host->unchecked_isa_dma : 1;
2061 sfp->cmd_q = SG_DEF_COMMAND_Q;
2062 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2063 sfp->parentdp = sdp;
2064 write_lock_irqsave(&sg_index_lock, iflags);
2065 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2066 write_unlock_irqrestore(&sg_index_lock, iflags);
2067 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
2068 if (unlikely(sg_big_buff != def_reserved_size))
2069 sg_big_buff = def_reserved_size;
2071 bufflen = min_t(int, sg_big_buff,
2072 queue_max_sectors(sdp->device->request_queue) * 512);
2073 sg_build_reserve(sfp, bufflen);
2074 SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2075 sfp->reserve.bufflen, sfp->reserve.k_use_sg));
2077 kref_get(&sdp->d_ref);
2078 __module_get(THIS_MODULE);
2079 return sfp;
2082 static void sg_remove_sfp_usercontext(struct work_struct *work)
2084 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2085 struct sg_device *sdp = sfp->parentdp;
2087 /* Cleanup any responses which were never read(). */
2088 while (sfp->headrp)
2089 sg_finish_rem_req(sfp->headrp);
2091 if (sfp->reserve.bufflen > 0) {
2092 SCSI_LOG_TIMEOUT(6,
2093 printk("sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",
2094 (int) sfp->reserve.bufflen,
2095 (int) sfp->reserve.k_use_sg));
2096 sg_remove_scat(&sfp->reserve);
2099 SCSI_LOG_TIMEOUT(6,
2100 printk("sg_remove_sfp: %s, sfp=0x%p\n",
2101 sdp->disk->disk_name,
2102 sfp));
2103 kfree(sfp);
2105 scsi_device_put(sdp->device);
2106 sg_put_dev(sdp);
2107 module_put(THIS_MODULE);
2110 static void sg_remove_sfp(struct kref *kref)
2112 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2113 struct sg_device *sdp = sfp->parentdp;
2114 unsigned long iflags;
2116 write_lock_irqsave(&sg_index_lock, iflags);
2117 list_del(&sfp->sfd_siblings);
2118 write_unlock_irqrestore(&sg_index_lock, iflags);
2119 wake_up_interruptible(&sdp->o_excl_wait);
2121 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2122 schedule_work(&sfp->ew.work);
2125 static int
2126 sg_res_in_use(Sg_fd * sfp)
2128 const Sg_request *srp;
2129 unsigned long iflags;
2131 read_lock_irqsave(&sfp->rq_list_lock, iflags);
2132 for (srp = sfp->headrp; srp; srp = srp->nextrp)
2133 if (srp->res_used)
2134 break;
2135 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2136 return srp ? 1 : 0;
2139 #ifdef CONFIG_SCSI_PROC_FS
2140 static int
2141 sg_idr_max_id(int id, void *p, void *data)
2143 int *k = data;
2145 if (*k < id)
2146 *k = id;
2148 return 0;
2151 static int
2152 sg_last_dev(void)
2154 int k = -1;
2155 unsigned long iflags;
2157 read_lock_irqsave(&sg_index_lock, iflags);
2158 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2159 read_unlock_irqrestore(&sg_index_lock, iflags);
2160 return k + 1; /* origin 1 */
2162 #endif
2164 /* must be called with sg_index_lock held */
2165 static Sg_device *sg_lookup_dev(int dev)
2167 return idr_find(&sg_index_idr, dev);
2170 static Sg_device *sg_get_dev(int dev)
2172 struct sg_device *sdp;
2173 unsigned long flags;
2175 read_lock_irqsave(&sg_index_lock, flags);
2176 sdp = sg_lookup_dev(dev);
2177 if (!sdp)
2178 sdp = ERR_PTR(-ENXIO);
2179 else if (sdp->detached) {
2180 /* If sdp->detached, then the refcount may already be 0, in
2181 * which case it would be a bug to do kref_get().
2183 sdp = ERR_PTR(-ENODEV);
2184 } else
2185 kref_get(&sdp->d_ref);
2186 read_unlock_irqrestore(&sg_index_lock, flags);
2188 return sdp;
2191 static void sg_put_dev(struct sg_device *sdp)
2193 kref_put(&sdp->d_ref, sg_device_destroy);
2196 #ifdef CONFIG_SCSI_PROC_FS
2198 static struct proc_dir_entry *sg_proc_sgp = NULL;
2200 static char sg_proc_sg_dirname[] = "scsi/sg";
2202 static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2204 static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2205 static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2206 size_t count, loff_t *off);
2207 static const struct file_operations adio_fops = {
2208 .owner = THIS_MODULE,
2209 .open = sg_proc_single_open_adio,
2210 .read = seq_read,
2211 .llseek = seq_lseek,
2212 .write = sg_proc_write_adio,
2213 .release = single_release,
2216 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2217 static ssize_t sg_proc_write_dressz(struct file *filp,
2218 const char __user *buffer, size_t count, loff_t *off);
2219 static const struct file_operations dressz_fops = {
2220 .owner = THIS_MODULE,
2221 .open = sg_proc_single_open_dressz,
2222 .read = seq_read,
2223 .llseek = seq_lseek,
2224 .write = sg_proc_write_dressz,
2225 .release = single_release,
2228 static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2229 static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2230 static const struct file_operations version_fops = {
2231 .owner = THIS_MODULE,
2232 .open = sg_proc_single_open_version,
2233 .read = seq_read,
2234 .llseek = seq_lseek,
2235 .release = single_release,
2238 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2239 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2240 static const struct file_operations devhdr_fops = {
2241 .owner = THIS_MODULE,
2242 .open = sg_proc_single_open_devhdr,
2243 .read = seq_read,
2244 .llseek = seq_lseek,
2245 .release = single_release,
2248 static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2249 static int sg_proc_open_dev(struct inode *inode, struct file *file);
2250 static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2251 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2252 static void dev_seq_stop(struct seq_file *s, void *v);
2253 static const struct file_operations dev_fops = {
2254 .owner = THIS_MODULE,
2255 .open = sg_proc_open_dev,
2256 .read = seq_read,
2257 .llseek = seq_lseek,
2258 .release = seq_release,
2260 static const struct seq_operations dev_seq_ops = {
2261 .start = dev_seq_start,
2262 .next = dev_seq_next,
2263 .stop = dev_seq_stop,
2264 .show = sg_proc_seq_show_dev,
2267 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2268 static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2269 static const struct file_operations devstrs_fops = {
2270 .owner = THIS_MODULE,
2271 .open = sg_proc_open_devstrs,
2272 .read = seq_read,
2273 .llseek = seq_lseek,
2274 .release = seq_release,
2276 static const struct seq_operations devstrs_seq_ops = {
2277 .start = dev_seq_start,
2278 .next = dev_seq_next,
2279 .stop = dev_seq_stop,
2280 .show = sg_proc_seq_show_devstrs,
2283 static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2284 static int sg_proc_open_debug(struct inode *inode, struct file *file);
2285 static const struct file_operations debug_fops = {
2286 .owner = THIS_MODULE,
2287 .open = sg_proc_open_debug,
2288 .read = seq_read,
2289 .llseek = seq_lseek,
2290 .release = seq_release,
2292 static const struct seq_operations debug_seq_ops = {
2293 .start = dev_seq_start,
2294 .next = dev_seq_next,
2295 .stop = dev_seq_stop,
2296 .show = sg_proc_seq_show_debug,
2300 struct sg_proc_leaf {
2301 const char * name;
2302 const struct file_operations * fops;
2305 static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2306 {"allow_dio", &adio_fops},
2307 {"debug", &debug_fops},
2308 {"def_reserved_size", &dressz_fops},
2309 {"device_hdr", &devhdr_fops},
2310 {"devices", &dev_fops},
2311 {"device_strs", &devstrs_fops},
2312 {"version", &version_fops}
2315 static int
2316 sg_proc_init(void)
2318 int k, mask;
2319 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2320 struct sg_proc_leaf * leaf;
2322 sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2323 if (!sg_proc_sgp)
2324 return 1;
2325 for (k = 0; k < num_leaves; ++k) {
2326 leaf = &sg_proc_leaf_arr[k];
2327 mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2328 proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2330 return 0;
2333 static void
2334 sg_proc_cleanup(void)
2336 int k;
2337 int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2339 if (!sg_proc_sgp)
2340 return;
2341 for (k = 0; k < num_leaves; ++k)
2342 remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2343 remove_proc_entry(sg_proc_sg_dirname, NULL);
2347 static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2349 seq_printf(s, "%d\n", *((int *)s->private));
2350 return 0;
2353 static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2355 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2358 static ssize_t
2359 sg_proc_write_adio(struct file *filp, const char __user *buffer,
2360 size_t count, loff_t *off)
2362 int num;
2363 char buff[11];
2365 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2366 return -EACCES;
2367 num = (count < 10) ? count : 10;
2368 if (copy_from_user(buff, buffer, num))
2369 return -EFAULT;
2370 buff[num] = '\0';
2371 sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2372 return count;
2375 static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2377 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2380 static ssize_t
2381 sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2382 size_t count, loff_t *off)
2384 int num;
2385 unsigned long k = ULONG_MAX;
2386 char buff[11];
2388 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2389 return -EACCES;
2390 num = (count < 10) ? count : 10;
2391 if (copy_from_user(buff, buffer, num))
2392 return -EFAULT;
2393 buff[num] = '\0';
2394 k = simple_strtoul(buff, NULL, 10);
2395 if (k <= 1048576) { /* limit "big buff" to 1 MB */
2396 sg_big_buff = k;
2397 return count;
2399 return -ERANGE;
2402 static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2404 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2405 sg_version_date);
2406 return 0;
2409 static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2411 return single_open(file, sg_proc_seq_show_version, NULL);
2414 static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2416 seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2417 "online\n");
2418 return 0;
2421 static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2423 return single_open(file, sg_proc_seq_show_devhdr, NULL);
2426 struct sg_proc_deviter {
2427 loff_t index;
2428 size_t max;
2431 static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2433 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2435 s->private = it;
2436 if (! it)
2437 return NULL;
2439 it->index = *pos;
2440 it->max = sg_last_dev();
2441 if (it->index >= it->max)
2442 return NULL;
2443 return it;
2446 static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2448 struct sg_proc_deviter * it = s->private;
2450 *pos = ++it->index;
2451 return (it->index < it->max) ? it : NULL;
2454 static void dev_seq_stop(struct seq_file *s, void *v)
2456 kfree(s->private);
2459 static int sg_proc_open_dev(struct inode *inode, struct file *file)
2461 return seq_open(file, &dev_seq_ops);
2464 static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2466 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2467 Sg_device *sdp;
2468 struct scsi_device *scsidp;
2469 unsigned long iflags;
2471 read_lock_irqsave(&sg_index_lock, iflags);
2472 sdp = it ? sg_lookup_dev(it->index) : NULL;
2473 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2474 seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
2475 scsidp->host->host_no, scsidp->channel,
2476 scsidp->id, scsidp->lun, (int) scsidp->type,
2478 (int) scsidp->queue_depth,
2479 (int) scsidp->device_busy,
2480 (int) scsi_device_online(scsidp));
2481 else
2482 seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2483 read_unlock_irqrestore(&sg_index_lock, iflags);
2484 return 0;
2487 static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2489 return seq_open(file, &devstrs_seq_ops);
2492 static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2494 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2495 Sg_device *sdp;
2496 struct scsi_device *scsidp;
2497 unsigned long iflags;
2499 read_lock_irqsave(&sg_index_lock, iflags);
2500 sdp = it ? sg_lookup_dev(it->index) : NULL;
2501 if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2502 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2503 scsidp->vendor, scsidp->model, scsidp->rev);
2504 else
2505 seq_printf(s, "<no active device>\n");
2506 read_unlock_irqrestore(&sg_index_lock, iflags);
2507 return 0;
2510 /* must be called while holding sg_index_lock */
2511 static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2513 int k, m, new_interface, blen, usg;
2514 Sg_request *srp;
2515 Sg_fd *fp;
2516 const sg_io_hdr_t *hp;
2517 const char * cp;
2518 unsigned int ms;
2520 k = 0;
2521 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2522 k++;
2523 read_lock(&fp->rq_list_lock); /* irqs already disabled */
2524 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "
2525 "(res)sgat=%d low_dma=%d\n", k,
2526 jiffies_to_msecs(fp->timeout),
2527 fp->reserve.bufflen,
2528 (int) fp->reserve.k_use_sg,
2529 (int) fp->low_dma);
2530 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2531 (int) fp->cmd_q, (int) fp->force_packid,
2532 (int) fp->keep_orphan, (int) fp->closed);
2533 for (m = 0, srp = fp->headrp;
2534 srp != NULL;
2535 ++m, srp = srp->nextrp) {
2536 hp = &srp->header;
2537 new_interface = (hp->interface_id == '\0') ? 0 : 1;
2538 if (srp->res_used) {
2539 if (new_interface &&
2540 (SG_FLAG_MMAP_IO & hp->flags))
2541 cp = " mmap>> ";
2542 else
2543 cp = " rb>> ";
2544 } else {
2545 if (SG_INFO_DIRECT_IO_MASK & hp->info)
2546 cp = " dio>> ";
2547 else
2548 cp = " ";
2550 seq_printf(s, cp);
2551 blen = srp->data.bufflen;
2552 usg = srp->data.k_use_sg;
2553 seq_printf(s, srp->done ?
2554 ((1 == srp->done) ? "rcv:" : "fin:")
2555 : "act:");
2556 seq_printf(s, " id=%d blen=%d",
2557 srp->header.pack_id, blen);
2558 if (srp->done)
2559 seq_printf(s, " dur=%d", hp->duration);
2560 else {
2561 ms = jiffies_to_msecs(jiffies);
2562 seq_printf(s, " t_o/elap=%d/%d",
2563 (new_interface ? hp->timeout :
2564 jiffies_to_msecs(fp->timeout)),
2565 (ms > hp->duration ? ms - hp->duration : 0));
2567 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2568 (int) srp->data.cmd_opcode);
2570 if (0 == m)
2571 seq_printf(s, " No requests active\n");
2572 read_unlock(&fp->rq_list_lock);
2576 static int sg_proc_open_debug(struct inode *inode, struct file *file)
2578 return seq_open(file, &debug_seq_ops);
2581 static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2583 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2584 Sg_device *sdp;
2585 unsigned long iflags;
2587 if (it && (0 == it->index)) {
2588 seq_printf(s, "max_active_device=%d(origin 1)\n",
2589 (int)it->max);
2590 seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2593 read_lock_irqsave(&sg_index_lock, iflags);
2594 sdp = it ? sg_lookup_dev(it->index) : NULL;
2595 if (sdp && !list_empty(&sdp->sfds)) {
2596 struct scsi_device *scsidp = sdp->device;
2598 seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2599 if (sdp->detached)
2600 seq_printf(s, "detached pending close ");
2601 else
2602 seq_printf
2603 (s, "scsi%d chan=%d id=%d lun=%d em=%d",
2604 scsidp->host->host_no,
2605 scsidp->channel, scsidp->id,
2606 scsidp->lun,
2607 scsidp->host->hostt->emulated);
2608 seq_printf(s, " sg_tablesize=%d excl=%d\n",
2609 sdp->sg_tablesize, sdp->exclude);
2610 sg_proc_debug_helper(s, sdp);
2612 read_unlock_irqrestore(&sg_index_lock, iflags);
2613 return 0;
2616 #endif /* CONFIG_SCSI_PROC_FS */
2618 module_init(init_sg);
2619 module_exit(exit_sg);