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v4.10.11
   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 - 2014 Douglas Gilbert
 
 
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2, or (at your option)
  15 * any later version.
  16 *
  17 */
  18
  19static int sg_version_num = 30536;	/* 2 digits for each component */
  20#define SG_VERSION_STR "3.5.36"
  21
  22/*
  23 *  D. P. Gilbert (dgilbert@interlog.com), notes:
  24 *      - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
  25 *        the kernel/module needs to be built with CONFIG_SCSI_LOGGING
  26 *        (otherwise the macros compile to empty statements).
  27 *
  28 */
  29#include <linux/module.h>
  30
  31#include <linux/fs.h>
  32#include <linux/kernel.h>
  33#include <linux/sched.h>
  34#include <linux/string.h>
  35#include <linux/mm.h>
  36#include <linux/errno.h>
  37#include <linux/mtio.h>
  38#include <linux/ioctl.h>
  39#include <linux/slab.h>
  40#include <linux/fcntl.h>
  41#include <linux/init.h>
  42#include <linux/poll.h>
  43#include <linux/moduleparam.h>
  44#include <linux/cdev.h>
  45#include <linux/idr.h>
  46#include <linux/seq_file.h>
  47#include <linux/blkdev.h>
  48#include <linux/delay.h>
  49#include <linux/blktrace_api.h>
  50#include <linux/mutex.h>
  51#include <linux/atomic.h>
  52#include <linux/ratelimit.h>
  53#include <linux/uio.h>
  54
  55#include "scsi.h"
  56#include <scsi/scsi_dbg.h>
  57#include <scsi/scsi_host.h>
  58#include <scsi/scsi_driver.h>
  59#include <scsi/scsi_ioctl.h>
  60#include <scsi/sg.h>
  61
  62#include "scsi_logging.h"
  63
  64#ifdef CONFIG_SCSI_PROC_FS
  65#include <linux/proc_fs.h>
  66static char *sg_version_date = "20140603";
  67
  68static int sg_proc_init(void);
  69static void sg_proc_cleanup(void);
  70#endif
  71
  72#define SG_ALLOW_DIO_DEF 0
  73
  74#define SG_MAX_DEVS 32768
  75
  76/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type
  77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater
  78 * than 16 bytes are "variable length" whose length is a multiple of 4
 
 
 
 
 
  79 */
  80#define SG_MAX_CDB_SIZE 252
  81
  82#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  83
  84int sg_big_buff = SG_DEF_RESERVED_SIZE;
  85/* N.B. This variable is readable and writeable via
  86   /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer
  87   of this size (or less if there is not enough memory) will be reserved
  88   for use by this file descriptor. [Deprecated usage: this variable is also
  89   readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into
  90   the kernel (i.e. it is not a module).] */
  91static int def_reserved_size = -1;	/* picks up init parameter */
  92static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  93
  94static int scatter_elem_sz = SG_SCATTER_SZ;
  95static int scatter_elem_sz_prev = SG_SCATTER_SZ;
  96
  97#define SG_SECTOR_SZ 512
  98
  99static int sg_add_device(struct device *, struct class_interface *);
 100static void sg_remove_device(struct device *, struct class_interface *);
 
 
 101
 102static DEFINE_IDR(sg_index_idr);
 103static DEFINE_RWLOCK(sg_index_lock);	/* Also used to lock
 104							   file descriptor list for device */
 105
 106static struct class_interface sg_interface = {
 107	.add_dev        = sg_add_device,
 108	.remove_dev     = sg_remove_device,
 109};
 110
 111typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
 112	unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
 113	unsigned sglist_len; /* size of malloc'd scatter-gather list ++ */
 114	unsigned bufflen;	/* Size of (aggregate) data buffer */
 115	struct page **pages;
 116	int page_order;
 117	char dio_in_use;	/* 0->indirect IO (or mmap), 1->dio */
 118	unsigned char cmd_opcode; /* first byte of command */
 119} Sg_scatter_hold;
 120
 121struct sg_device;		/* forward declarations */
 122struct sg_fd;
 123
 124typedef struct sg_request {	/* SG_MAX_QUEUE requests outstanding per file */
 125	struct sg_request *nextrp;	/* NULL -> tail request (slist) */
 126	struct sg_fd *parentfp;	/* NULL -> not in use */
 127	Sg_scatter_hold data;	/* hold buffer, perhaps scatter list */
 128	sg_io_hdr_t header;	/* scsi command+info, see <scsi/sg.h> */
 129	unsigned char sense_b[SCSI_SENSE_BUFFERSIZE];
 130	char res_used;		/* 1 -> using reserve buffer, 0 -> not ... */
 131	char orphan;		/* 1 -> drop on sight, 0 -> normal */
 132	char sg_io_owned;	/* 1 -> packet belongs to SG_IO */
 133	/* done protected by rq_list_lock */
 134	char done;		/* 0->before bh, 1->before read, 2->read */
 135	struct request *rq;
 136	struct bio *bio;
 137	struct execute_work ew;
 138} Sg_request;
 139
 140typedef struct sg_fd {		/* holds the state of a file descriptor */
 141	struct list_head sfd_siblings;  /* protected by device's sfd_lock */
 142	struct sg_device *parentdp;	/* owning device */
 143	wait_queue_head_t read_wait;	/* queue read until command done */
 144	rwlock_t rq_list_lock;	/* protect access to list in req_arr */
 145	int timeout;		/* defaults to SG_DEFAULT_TIMEOUT      */
 146	int timeout_user;	/* defaults to SG_DEFAULT_TIMEOUT_USER */
 147	Sg_scatter_hold reserve;	/* buffer held for this file descriptor */
 148	unsigned save_scat_len;	/* original length of trunc. scat. element */
 149	Sg_request *headrp;	/* head of request slist, NULL->empty */
 150	struct fasync_struct *async_qp;	/* used by asynchronous notification */
 151	Sg_request req_arr[SG_MAX_QUEUE];	/* used as singly-linked list */
 152	char low_dma;		/* as in parent but possibly overridden to 1 */
 153	char force_packid;	/* 1 -> pack_id input to read(), 0 -> ignored */
 
 154	char cmd_q;		/* 1 -> allow command queuing, 0 -> don't */
 155	unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */
 156	char keep_orphan;	/* 0 -> drop orphan (def), 1 -> keep for read() */
 157	char mmap_called;	/* 0 -> mmap() never called on this fd */
 158	struct kref f_ref;
 159	struct execute_work ew;
 160} Sg_fd;
 161
 162typedef struct sg_device { /* holds the state of each scsi generic device */
 163	struct scsi_device *device;
 164	wait_queue_head_t open_wait;    /* queue open() when O_EXCL present */
 165	struct mutex open_rel_lock;     /* held when in open() or release() */
 166	int sg_tablesize;	/* adapter's max scatter-gather table size */
 167	u32 index;		/* device index number */
 168	struct list_head sfds;
 169	rwlock_t sfd_lock;      /* protect access to sfd list */
 170	atomic_t detaching;     /* 0->device usable, 1->device detaching */
 171	bool exclude;		/* 1->open(O_EXCL) succeeded and is active */
 172	int open_cnt;		/* count of opens (perhaps < num(sfds) ) */
 173	char sgdebug;		/* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 174	struct gendisk *disk;
 175	struct cdev * cdev;	/* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 176	struct kref d_ref;
 177} Sg_device;
 178
 179/* tasklet or soft irq callback */
 180static void sg_rq_end_io(struct request *rq, int uptodate);
 181static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 182static int sg_finish_rem_req(Sg_request * srp);
 183static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 184static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 185			   Sg_request * srp);
 186static 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, int sg_io_owned, Sg_request **o_srp);
 189static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 190			   unsigned char *cmnd, int timeout, int blocking);
 191static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 192static void sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp);
 193static void sg_build_reserve(Sg_fd * sfp, int req_size);
 194static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 195static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 196static Sg_fd *sg_add_sfp(Sg_device * sdp);
 197static void sg_remove_sfp(struct kref *);
 198static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 199static Sg_request *sg_add_request(Sg_fd * sfp);
 200static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 201static int sg_res_in_use(Sg_fd * sfp);
 202static Sg_device *sg_get_dev(int dev);
 203static void sg_device_destroy(struct kref *kref);
 204
 205#define SZ_SG_HEADER sizeof(struct sg_header)
 206#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 207#define SZ_SG_IOVEC sizeof(sg_iovec_t)
 208#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 209
 210#define sg_printk(prefix, sdp, fmt, a...) \
 211	sdev_prefix_printk(prefix, (sdp)->device,		\
 212			   (sdp)->disk->disk_name, fmt, ##a)
 213
 214static int sg_allow_access(struct file *filp, unsigned char *cmd)
 215{
 216	struct sg_fd *sfp = filp->private_data;
 217
 218	if (sfp->parentdp->device->type == TYPE_SCANNER)
 219		return 0;
 220
 221	return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 222}
 223
 224static int
 225open_wait(Sg_device *sdp, int flags)
 226{
 227	int retval = 0;
 228
 229	if (flags & O_EXCL) {
 230		while (sdp->open_cnt > 0) {
 231			mutex_unlock(&sdp->open_rel_lock);
 232			retval = wait_event_interruptible(sdp->open_wait,
 233					(atomic_read(&sdp->detaching) ||
 234					 !sdp->open_cnt));
 235			mutex_lock(&sdp->open_rel_lock);
 236
 237			if (retval) /* -ERESTARTSYS */
 238				return retval;
 239			if (atomic_read(&sdp->detaching))
 240				return -ENODEV;
 241		}
 242	} else {
 243		while (sdp->exclude) {
 244			mutex_unlock(&sdp->open_rel_lock);
 245			retval = wait_event_interruptible(sdp->open_wait,
 246					(atomic_read(&sdp->detaching) ||
 247					 !sdp->exclude));
 248			mutex_lock(&sdp->open_rel_lock);
 249
 250			if (retval) /* -ERESTARTSYS */
 251				return retval;
 252			if (atomic_read(&sdp->detaching))
 253				return -ENODEV;
 254		}
 255	}
 256
 257	return retval;
 258}
 259
 260/* Returns 0 on success, else a negated errno value */
 261static int
 262sg_open(struct inode *inode, struct file *filp)
 263{
 264	int dev = iminor(inode);
 265	int flags = filp->f_flags;
 266	struct request_queue *q;
 267	Sg_device *sdp;
 268	Sg_fd *sfp;
 
 269	int retval;
 270
 
 271	nonseekable_open(inode, filp);
 272	if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))
 273		return -EPERM; /* Can't lock it with read only access */
 274	sdp = sg_get_dev(dev);
 275	if (IS_ERR(sdp))
 276		return PTR_ERR(sdp);
 277
 278	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 279				      "sg_open: flags=0x%x\n", flags));
 280
 281	/* This driver's module count bumped by fops_get in <linux/fs.h> */
 282	/* Prevent the device driver from vanishing while we sleep */
 283	retval = scsi_device_get(sdp->device);
 284	if (retval)
 285		goto sg_put;
 286
 287	retval = scsi_autopm_get_device(sdp->device);
 288	if (retval)
 289		goto sdp_put;
 290
 291	/* scsi_block_when_processing_errors() may block so bypass
 292	 * check if O_NONBLOCK. Permits SCSI commands to be issued
 293	 * during error recovery. Tread carefully. */
 294	if (!((flags & O_NONBLOCK) ||
 295	      scsi_block_when_processing_errors(sdp->device))) {
 296		retval = -ENXIO;
 297		/* we are in error recovery for this device */
 298		goto error_out;
 299	}
 300
 301	mutex_lock(&sdp->open_rel_lock);
 302	if (flags & O_NONBLOCK) {
 303		if (flags & O_EXCL) {
 304			if (sdp->open_cnt > 0) {
 305				retval = -EBUSY;
 306				goto error_mutex_locked;
 307			}
 308		} else {
 309			if (sdp->exclude) {
 310				retval = -EBUSY;
 311				goto error_mutex_locked;
 312			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 313		}
 314	} else {
 315		retval = open_wait(sdp, flags);
 316		if (retval) /* -ERESTARTSYS or -ENODEV */
 317			goto error_mutex_locked;
 318	}
 319
 320	/* N.B. at this point we are holding the open_rel_lock */
 321	if (flags & O_EXCL)
 322		sdp->exclude = true;
 323
 324	if (sdp->open_cnt < 1) {  /* no existing opens */
 325		sdp->sgdebug = 0;
 326		q = sdp->device->request_queue;
 327		sdp->sg_tablesize = queue_max_segments(q);
 328	}
 329	sfp = sg_add_sfp(sdp);
 330	if (IS_ERR(sfp)) {
 331		retval = PTR_ERR(sfp);
 332		goto out_undo;
 
 
 
 
 
 333	}
 334
 335	filp->private_data = sfp;
 336	sdp->open_cnt++;
 337	mutex_unlock(&sdp->open_rel_lock);
 338
 339	retval = 0;
 340sg_put:
 341	kref_put(&sdp->d_ref, sg_device_destroy);
 342	return retval;
 343
 344out_undo:
 345	if (flags & O_EXCL) {
 346		sdp->exclude = false;   /* undo if error */
 347		wake_up_interruptible(&sdp->open_wait);
 348	}
 349error_mutex_locked:
 350	mutex_unlock(&sdp->open_rel_lock);
 351error_out:
 352	scsi_autopm_put_device(sdp->device);
 
 353sdp_put:
 354	scsi_device_put(sdp->device);
 355	goto sg_put;
 
 
 
 
 
 356}
 357
 358/* Release resources associated with a successful sg_open()
 359 * Returns 0 on success, else a negated errno value */
 360static int
 361sg_release(struct inode *inode, struct file *filp)
 362{
 363	Sg_device *sdp;
 364	Sg_fd *sfp;
 365
 366	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 367		return -ENXIO;
 368	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));
 
 
 
 
 
 369
 370	mutex_lock(&sdp->open_rel_lock);
 371	scsi_autopm_put_device(sdp->device);
 372	kref_put(&sfp->f_ref, sg_remove_sfp);
 373	sdp->open_cnt--;
 374
 375	/* possibly many open()s waiting on exlude clearing, start many;
 376	 * only open(O_EXCL)s wait on 0==open_cnt so only start one */
 377	if (sdp->exclude) {
 378		sdp->exclude = false;
 379		wake_up_interruptible_all(&sdp->open_wait);
 380	} else if (0 == sdp->open_cnt) {
 381		wake_up_interruptible(&sdp->open_wait);
 382	}
 383	mutex_unlock(&sdp->open_rel_lock);
 384	return 0;
 385}
 386
 387static ssize_t
 388sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 389{
 390	Sg_device *sdp;
 391	Sg_fd *sfp;
 392	Sg_request *srp;
 393	int req_pack_id = -1;
 394	sg_io_hdr_t *hp;
 395	struct sg_header *old_hdr = NULL;
 396	int retval = 0;
 397
 398	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 399		return -ENXIO;
 400	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 401				      "sg_read: count=%d\n", (int) count));
 402
 403	if (!access_ok(VERIFY_WRITE, buf, count))
 404		return -EFAULT;
 405	if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 406		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 407		if (!old_hdr)
 408			return -ENOMEM;
 409		if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 410			retval = -EFAULT;
 411			goto free_old_hdr;
 412		}
 413		if (old_hdr->reply_len < 0) {
 414			if (count >= SZ_SG_IO_HDR) {
 415				sg_io_hdr_t *new_hdr;
 416				new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 417				if (!new_hdr) {
 418					retval = -ENOMEM;
 419					goto free_old_hdr;
 420				}
 421				retval =__copy_from_user
 422				    (new_hdr, buf, SZ_SG_IO_HDR);
 423				req_pack_id = new_hdr->pack_id;
 424				kfree(new_hdr);
 425				if (retval) {
 426					retval = -EFAULT;
 427					goto free_old_hdr;
 428				}
 429			}
 430		} else
 431			req_pack_id = old_hdr->pack_id;
 432	}
 433	srp = sg_get_rq_mark(sfp, req_pack_id);
 434	if (!srp) {		/* now wait on packet to arrive */
 435		if (atomic_read(&sdp->detaching)) {
 436			retval = -ENODEV;
 437			goto free_old_hdr;
 438		}
 439		if (filp->f_flags & O_NONBLOCK) {
 440			retval = -EAGAIN;
 441			goto free_old_hdr;
 442		}
 443		retval = wait_event_interruptible(sfp->read_wait,
 444			(atomic_read(&sdp->detaching) ||
 445			(srp = sg_get_rq_mark(sfp, req_pack_id))));
 446		if (atomic_read(&sdp->detaching)) {
 447			retval = -ENODEV;
 448			goto free_old_hdr;
 449		}
 450		if (retval) {
 
 
 
 
 
 451			/* -ERESTARTSYS as signal hit process */
 452			goto free_old_hdr;
 453		}
 454	}
 455	if (srp->header.interface_id != '\0') {
 456		retval = sg_new_read(sfp, buf, count, srp);
 457		goto free_old_hdr;
 458	}
 459
 460	hp = &srp->header;
 461	if (old_hdr == NULL) {
 462		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 463		if (! old_hdr) {
 464			retval = -ENOMEM;
 465			goto free_old_hdr;
 466		}
 467	}
 468	memset(old_hdr, 0, SZ_SG_HEADER);
 469	old_hdr->reply_len = (int) hp->timeout;
 470	old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 471	old_hdr->pack_id = hp->pack_id;
 472	old_hdr->twelve_byte =
 473	    ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 474	old_hdr->target_status = hp->masked_status;
 475	old_hdr->host_status = hp->host_status;
 476	old_hdr->driver_status = hp->driver_status;
 477	if ((CHECK_CONDITION & hp->masked_status) ||
 478	    (DRIVER_SENSE & hp->driver_status))
 479		memcpy(old_hdr->sense_buffer, srp->sense_b,
 480		       sizeof (old_hdr->sense_buffer));
 481	switch (hp->host_status) {
 482	/* This setup of 'result' is for backward compatibility and is best
 483	   ignored by the user who should use target, host + driver status */
 484	case DID_OK:
 485	case DID_PASSTHROUGH:
 486	case DID_SOFT_ERROR:
 487		old_hdr->result = 0;
 488		break;
 489	case DID_NO_CONNECT:
 490	case DID_BUS_BUSY:
 491	case DID_TIME_OUT:
 492		old_hdr->result = EBUSY;
 493		break;
 494	case DID_BAD_TARGET:
 495	case DID_ABORT:
 496	case DID_PARITY:
 497	case DID_RESET:
 498	case DID_BAD_INTR:
 499		old_hdr->result = EIO;
 500		break;
 501	case DID_ERROR:
 502		old_hdr->result = (srp->sense_b[0] == 0 && 
 503				  hp->masked_status == GOOD) ? 0 : EIO;
 504		break;
 505	default:
 506		old_hdr->result = EIO;
 507		break;
 508	}
 509
 510	/* Now copy the result back to the user buffer.  */
 511	if (count >= SZ_SG_HEADER) {
 512		if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 513			retval = -EFAULT;
 514			goto free_old_hdr;
 515		}
 516		buf += SZ_SG_HEADER;
 517		if (count > old_hdr->reply_len)
 518			count = old_hdr->reply_len;
 519		if (count > SZ_SG_HEADER) {
 520			if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 521				retval = -EFAULT;
 522				goto free_old_hdr;
 523			}
 524		}
 525	} else
 526		count = (old_hdr->result == 0) ? 0 : -EIO;
 527	sg_finish_rem_req(srp);
 528	retval = count;
 529free_old_hdr:
 530	kfree(old_hdr);
 531	return retval;
 532}
 533
 534static ssize_t
 535sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 536{
 537	sg_io_hdr_t *hp = &srp->header;
 538	int err = 0, err2;
 539	int len;
 540
 541	if (count < SZ_SG_IO_HDR) {
 542		err = -EINVAL;
 543		goto err_out;
 544	}
 545	hp->sb_len_wr = 0;
 546	if ((hp->mx_sb_len > 0) && hp->sbp) {
 547		if ((CHECK_CONDITION & hp->masked_status) ||
 548		    (DRIVER_SENSE & hp->driver_status)) {
 549			int sb_len = SCSI_SENSE_BUFFERSIZE;
 550			sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 551			len = 8 + (int) srp->sense_b[7];	/* Additional sense length field */
 552			len = (len > sb_len) ? sb_len : len;
 553			if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 554				err = -EFAULT;
 555				goto err_out;
 556			}
 557			hp->sb_len_wr = len;
 558		}
 559	}
 560	if (hp->masked_status || hp->host_status || hp->driver_status)
 561		hp->info |= SG_INFO_CHECK;
 562	if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 563		err = -EFAULT;
 564		goto err_out;
 565	}
 566err_out:
 567	err2 = sg_finish_rem_req(srp);
 568	return err ? : err2 ? : count;
 569}
 570
 571static ssize_t
 572sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 573{
 574	int mxsize, cmd_size, k;
 575	int input_size, blocking;
 576	unsigned char opcode;
 577	Sg_device *sdp;
 578	Sg_fd *sfp;
 579	Sg_request *srp;
 580	struct sg_header old_hdr;
 581	sg_io_hdr_t *hp;
 582	unsigned char cmnd[SG_MAX_CDB_SIZE];
 583
 584	if (unlikely(segment_eq(get_fs(), KERNEL_DS)))
 585		return -EINVAL;
 586
 587	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 588		return -ENXIO;
 589	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 590				      "sg_write: count=%d\n", (int) count));
 591	if (atomic_read(&sdp->detaching))
 592		return -ENODEV;
 593	if (!((filp->f_flags & O_NONBLOCK) ||
 594	      scsi_block_when_processing_errors(sdp->device)))
 595		return -ENXIO;
 596
 597	if (!access_ok(VERIFY_READ, buf, count))
 598		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 599	if (count < SZ_SG_HEADER)
 600		return -EIO;
 601	if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 602		return -EFAULT;
 603	blocking = !(filp->f_flags & O_NONBLOCK);
 604	if (old_hdr.reply_len < 0)
 605		return sg_new_write(sfp, filp, buf, count,
 606				    blocking, 0, 0, NULL);
 607	if (count < (SZ_SG_HEADER + 6))
 608		return -EIO;	/* The minimum scsi command length is 6 bytes. */
 609
 610	if (!(srp = sg_add_request(sfp))) {
 611		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,
 612					      "sg_write: queue full\n"));
 613		return -EDOM;
 614	}
 615	buf += SZ_SG_HEADER;
 616	__get_user(opcode, buf);
 617	if (sfp->next_cmd_len > 0) {
 
 
 
 
 
 
 618		cmd_size = sfp->next_cmd_len;
 619		sfp->next_cmd_len = 0;	/* reset so only this write() effected */
 620	} else {
 621		cmd_size = COMMAND_SIZE(opcode);	/* based on SCSI command group */
 622		if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 623			cmd_size = 12;
 624	}
 625	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
 626		"sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 627/* Determine buffer size.  */
 628	input_size = count - cmd_size;
 629	mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 630	mxsize -= SZ_SG_HEADER;
 631	input_size -= SZ_SG_HEADER;
 632	if (input_size < 0) {
 633		sg_remove_request(sfp, srp);
 634		return -EIO;	/* User did not pass enough bytes for this command. */
 635	}
 636	hp = &srp->header;
 637	hp->interface_id = '\0';	/* indicator of old interface tunnelled */
 638	hp->cmd_len = (unsigned char) cmd_size;
 639	hp->iovec_count = 0;
 640	hp->mx_sb_len = 0;
 641	if (input_size > 0)
 642		hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 643		    SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 644	else
 645		hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 646	hp->dxfer_len = mxsize;
 647	if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||
 648	    (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))
 649		hp->dxferp = (char __user *)buf + cmd_size;
 650	else
 651		hp->dxferp = NULL;
 652	hp->sbp = NULL;
 653	hp->timeout = old_hdr.reply_len;	/* structure abuse ... */
 654	hp->flags = input_size;	/* structure abuse ... */
 655	hp->pack_id = old_hdr.pack_id;
 656	hp->usr_ptr = NULL;
 657	if (__copy_from_user(cmnd, buf, cmd_size))
 658		return -EFAULT;
 659	/*
 660	 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 661	 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 662	 * is a non-zero input_size, so emit a warning.
 663	 */
 664	if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 665		static char cmd[TASK_COMM_LEN];
 666		if (strcmp(current->comm, cmd)) {
 667			printk_ratelimited(KERN_WARNING
 668					   "sg_write: data in/out %d/%d bytes "
 669					   "for SCSI command 0x%x-- guessing "
 670					   "data in;\n   program %s not setting "
 671					   "count and/or reply_len properly\n",
 672					   old_hdr.reply_len - (int)SZ_SG_HEADER,
 673					   input_size, (unsigned int) cmnd[0],
 674					   current->comm);
 675			strcpy(cmd, current->comm);
 676		}
 677	}
 678	k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 679	return (k < 0) ? k : count;
 680}
 681
 682static ssize_t
 683sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 684		 size_t count, int blocking, int read_only, int sg_io_owned,
 685		 Sg_request **o_srp)
 686{
 687	int k;
 688	Sg_request *srp;
 689	sg_io_hdr_t *hp;
 690	unsigned char cmnd[SG_MAX_CDB_SIZE];
 691	int timeout;
 692	unsigned long ul_timeout;
 693
 694	if (count < SZ_SG_IO_HDR)
 695		return -EINVAL;
 696	if (!access_ok(VERIFY_READ, buf, count))
 697		return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 698
 699	sfp->cmd_q = 1;	/* when sg_io_hdr seen, set command queuing on */
 700	if (!(srp = sg_add_request(sfp))) {
 701		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
 702					      "sg_new_write: queue full\n"));
 703		return -EDOM;
 704	}
 705	srp->sg_io_owned = sg_io_owned;
 706	hp = &srp->header;
 707	if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 708		sg_remove_request(sfp, srp);
 709		return -EFAULT;
 710	}
 711	if (hp->interface_id != 'S') {
 712		sg_remove_request(sfp, srp);
 713		return -ENOSYS;
 714	}
 715	if (hp->flags & SG_FLAG_MMAP_IO) {
 716		if (hp->dxfer_len > sfp->reserve.bufflen) {
 717			sg_remove_request(sfp, srp);
 718			return -ENOMEM;	/* MMAP_IO size must fit in reserve buffer */
 719		}
 720		if (hp->flags & SG_FLAG_DIRECT_IO) {
 721			sg_remove_request(sfp, srp);
 722			return -EINVAL;	/* either MMAP_IO or DIRECT_IO (not both) */
 723		}
 724		if (sg_res_in_use(sfp)) {
 725			sg_remove_request(sfp, srp);
 726			return -EBUSY;	/* reserve buffer already being used */
 727		}
 728	}
 729	ul_timeout = msecs_to_jiffies(srp->header.timeout);
 730	timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 731	if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 732		sg_remove_request(sfp, srp);
 733		return -EMSGSIZE;
 734	}
 735	if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 736		sg_remove_request(sfp, srp);
 737		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 738	}
 739	if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 740		sg_remove_request(sfp, srp);
 741		return -EFAULT;
 742	}
 743	if (read_only && sg_allow_access(file, cmnd)) {
 744		sg_remove_request(sfp, srp);
 745		return -EPERM;
 746	}
 747	k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 748	if (k < 0)
 749		return k;
 750	if (o_srp)
 751		*o_srp = srp;
 752	return count;
 753}
 754
 755static int
 756sg_common_write(Sg_fd * sfp, Sg_request * srp,
 757		unsigned char *cmnd, int timeout, int blocking)
 758{
 759	int k, at_head;
 760	Sg_device *sdp = sfp->parentdp;
 761	sg_io_hdr_t *hp = &srp->header;
 762
 763	srp->data.cmd_opcode = cmnd[0];	/* hold opcode of command */
 764	hp->status = 0;
 765	hp->masked_status = 0;
 766	hp->msg_status = 0;
 767	hp->info = 0;
 768	hp->host_status = 0;
 769	hp->driver_status = 0;
 770	hp->resid = 0;
 771	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
 772			"sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 773			(int) cmnd[0], (int) hp->cmd_len));
 774
 775	k = sg_start_req(srp, cmnd);
 776	if (k) {
 777		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
 778			"sg_common_write: start_req err=%d\n", k));
 779		sg_finish_rem_req(srp);
 780		return k;	/* probably out of space --> ENOMEM */
 781	}
 782	if (atomic_read(&sdp->detaching)) {
 783		if (srp->bio) {
 784			if (srp->rq->cmd != srp->rq->__cmd)
 785				kfree(srp->rq->cmd);
 786
 787			blk_end_request_all(srp->rq, -EIO);
 788			srp->rq = NULL;
 789		}
 790
 791		sg_finish_rem_req(srp);
 792		return -ENODEV;
 793	}
 794
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 795	hp->duration = jiffies_to_msecs(jiffies);
 796	if (hp->interface_id != '\0' &&	/* v3 (or later) interface */
 797	    (SG_FLAG_Q_AT_TAIL & hp->flags))
 798		at_head = 0;
 799	else
 800		at_head = 1;
 801
 802	srp->rq->timeout = timeout;
 803	kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 804	blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 805			      srp->rq, at_head, sg_rq_end_io);
 806	return 0;
 807}
 808
 809static int srp_done(Sg_fd *sfp, Sg_request *srp)
 810{
 811	unsigned long flags;
 812	int ret;
 813
 814	read_lock_irqsave(&sfp->rq_list_lock, flags);
 815	ret = srp->done;
 816	read_unlock_irqrestore(&sfp->rq_list_lock, flags);
 817	return ret;
 818}
 819
 820static int max_sectors_bytes(struct request_queue *q)
 821{
 822	unsigned int max_sectors = queue_max_sectors(q);
 823
 824	max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);
 825
 826	return max_sectors << 9;
 827}
 828
 829static long
 830sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 831{
 832	void __user *p = (void __user *)arg;
 833	int __user *ip = p;
 834	int result, val, read_only;
 835	Sg_device *sdp;
 836	Sg_fd *sfp;
 837	Sg_request *srp;
 838	unsigned long iflags;
 839
 840	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 841		return -ENXIO;
 842
 843	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
 844				   "sg_ioctl: cmd=0x%x\n", (int) cmd_in));
 845	read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 846
 847	switch (cmd_in) {
 848	case SG_IO:
 849		if (atomic_read(&sdp->detaching))
 850			return -ENODEV;
 851		if (!scsi_block_when_processing_errors(sdp->device))
 852			return -ENXIO;
 853		if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 854			return -EFAULT;
 855		result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 856				 1, read_only, 1, &srp);
 857		if (result < 0)
 858			return result;
 859		result = wait_event_interruptible(sfp->read_wait,
 860			(srp_done(sfp, srp) || atomic_read(&sdp->detaching)));
 861		if (atomic_read(&sdp->detaching))
 862			return -ENODEV;
 863		write_lock_irq(&sfp->rq_list_lock);
 864		if (srp->done) {
 865			srp->done = 2;
 866			write_unlock_irq(&sfp->rq_list_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 867			result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 868			return (result < 0) ? result : 0;
 869		}
 870		srp->orphan = 1;
 871		write_unlock_irq(&sfp->rq_list_lock);
 872		return result;	/* -ERESTARTSYS because signal hit process */
 873	case SG_SET_TIMEOUT:
 874		result = get_user(val, ip);
 875		if (result)
 876			return result;
 877		if (val < 0)
 878			return -EIO;
 879		if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))
 880			val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),
 881				    INT_MAX);
 882		sfp->timeout_user = val;
 883		sfp->timeout = mult_frac(val, HZ, USER_HZ);
 884
 885		return 0;
 886	case SG_GET_TIMEOUT:	/* N.B. User receives timeout as return value */
 887				/* strange ..., for backward compatibility */
 888		return sfp->timeout_user;
 889	case SG_SET_FORCE_LOW_DMA:
 890		result = get_user(val, ip);
 891		if (result)
 892			return result;
 893		if (val) {
 894			sfp->low_dma = 1;
 895			if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 896				val = (int) sfp->reserve.bufflen;
 897				sg_remove_scat(sfp, &sfp->reserve);
 898				sg_build_reserve(sfp, val);
 899			}
 900		} else {
 901			if (atomic_read(&sdp->detaching))
 902				return -ENODEV;
 903			sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 904		}
 905		return 0;
 906	case SG_GET_LOW_DMA:
 907		return put_user((int) sfp->low_dma, ip);
 908	case SG_GET_SCSI_ID:
 909		if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 910			return -EFAULT;
 911		else {
 912			sg_scsi_id_t __user *sg_idp = p;
 913
 914			if (atomic_read(&sdp->detaching))
 915				return -ENODEV;
 916			__put_user((int) sdp->device->host->host_no,
 917				   &sg_idp->host_no);
 918			__put_user((int) sdp->device->channel,
 919				   &sg_idp->channel);
 920			__put_user((int) sdp->device->id, &sg_idp->scsi_id);
 921			__put_user((int) sdp->device->lun, &sg_idp->lun);
 922			__put_user((int) sdp->device->type, &sg_idp->scsi_type);
 923			__put_user((short) sdp->device->host->cmd_per_lun,
 924				   &sg_idp->h_cmd_per_lun);
 925			__put_user((short) sdp->device->queue_depth,
 926				   &sg_idp->d_queue_depth);
 927			__put_user(0, &sg_idp->unused[0]);
 928			__put_user(0, &sg_idp->unused[1]);
 929			return 0;
 930		}
 931	case SG_SET_FORCE_PACK_ID:
 932		result = get_user(val, ip);
 933		if (result)
 934			return result;
 935		sfp->force_packid = val ? 1 : 0;
 936		return 0;
 937	case SG_GET_PACK_ID:
 938		if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 939			return -EFAULT;
 940		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 941		for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 942			if ((1 == srp->done) && (!srp->sg_io_owned)) {
 943				read_unlock_irqrestore(&sfp->rq_list_lock,
 944						       iflags);
 945				__put_user(srp->header.pack_id, ip);
 946				return 0;
 947			}
 948		}
 949		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 950		__put_user(-1, ip);
 951		return 0;
 952	case SG_GET_NUM_WAITING:
 953		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 954		for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 955			if ((1 == srp->done) && (!srp->sg_io_owned))
 956				++val;
 957		}
 958		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 959		return put_user(val, ip);
 960	case SG_GET_SG_TABLESIZE:
 961		return put_user(sdp->sg_tablesize, ip);
 962	case SG_SET_RESERVED_SIZE:
 963		result = get_user(val, ip);
 964		if (result)
 965			return result;
 966                if (val < 0)
 967                        return -EINVAL;
 968		val = min_t(int, val,
 969			    max_sectors_bytes(sdp->device->request_queue));
 970		if (val != sfp->reserve.bufflen) {
 971			if (sg_res_in_use(sfp) || sfp->mmap_called)
 972				return -EBUSY;
 973			sg_remove_scat(sfp, &sfp->reserve);
 974			sg_build_reserve(sfp, val);
 975		}
 976		return 0;
 977	case SG_GET_RESERVED_SIZE:
 978		val = min_t(int, sfp->reserve.bufflen,
 979			    max_sectors_bytes(sdp->device->request_queue));
 980		return put_user(val, ip);
 981	case SG_SET_COMMAND_Q:
 982		result = get_user(val, ip);
 983		if (result)
 984			return result;
 985		sfp->cmd_q = val ? 1 : 0;
 986		return 0;
 987	case SG_GET_COMMAND_Q:
 988		return put_user((int) sfp->cmd_q, ip);
 989	case SG_SET_KEEP_ORPHAN:
 990		result = get_user(val, ip);
 991		if (result)
 992			return result;
 993		sfp->keep_orphan = val;
 994		return 0;
 995	case SG_GET_KEEP_ORPHAN:
 996		return put_user((int) sfp->keep_orphan, ip);
 997	case SG_NEXT_CMD_LEN:
 998		result = get_user(val, ip);
 999		if (result)
1000			return result;
1001		if (val > SG_MAX_CDB_SIZE)
1002			return -ENOMEM;
1003		sfp->next_cmd_len = (val > 0) ? val : 0;
1004		return 0;
1005	case SG_GET_VERSION_NUM:
1006		return put_user(sg_version_num, ip);
1007	case SG_GET_ACCESS_COUNT:
1008		/* faked - we don't have a real access count anymore */
1009		val = (sdp->device ? 1 : 0);
1010		return put_user(val, ip);
1011	case SG_GET_REQUEST_TABLE:
1012		if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
1013			return -EFAULT;
1014		else {
1015			sg_req_info_t *rinfo;
1016			unsigned int ms;
1017
1018			rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
1019								GFP_KERNEL);
1020			if (!rinfo)
1021				return -ENOMEM;
1022			read_lock_irqsave(&sfp->rq_list_lock, iflags);
1023			for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
1024			     ++val, srp = srp ? srp->nextrp : srp) {
1025				memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
1026				if (srp) {
1027					rinfo[val].req_state = srp->done + 1;
1028					rinfo[val].problem =
1029					    srp->header.masked_status & 
1030					    srp->header.host_status & 
1031					    srp->header.driver_status;
1032					if (srp->done)
1033						rinfo[val].duration =
1034							srp->header.duration;
1035					else {
1036						ms = jiffies_to_msecs(jiffies);
1037						rinfo[val].duration =
1038						    (ms > srp->header.duration) ?
1039						    (ms - srp->header.duration) : 0;
1040					}
1041					rinfo[val].orphan = srp->orphan;
1042					rinfo[val].sg_io_owned =
1043							srp->sg_io_owned;
1044					rinfo[val].pack_id =
1045							srp->header.pack_id;
1046					rinfo[val].usr_ptr =
1047							srp->header.usr_ptr;
1048				}
1049			}
1050			read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1051			result = __copy_to_user(p, rinfo, 
1052						SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1053			result = result ? -EFAULT : 0;
1054			kfree(rinfo);
1055			return result;
1056		}
1057	case SG_EMULATED_HOST:
1058		if (atomic_read(&sdp->detaching))
1059			return -ENODEV;
1060		return put_user(sdp->device->host->hostt->emulated, ip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1061	case SCSI_IOCTL_SEND_COMMAND:
1062		if (atomic_read(&sdp->detaching))
1063			return -ENODEV;
1064		if (read_only) {
1065			unsigned char opcode = WRITE_6;
1066			Scsi_Ioctl_Command __user *siocp = p;
1067
1068			if (copy_from_user(&opcode, siocp->data, 1))
1069				return -EFAULT;
1070			if (sg_allow_access(filp, &opcode))
1071				return -EPERM;
1072		}
1073		return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1074	case SG_SET_DEBUG:
1075		result = get_user(val, ip);
1076		if (result)
1077			return result;
1078		sdp->sgdebug = (char) val;
1079		return 0;
 
 
 
 
 
 
 
1080	case BLKSECTGET:
1081		return put_user(max_sectors_bytes(sdp->device->request_queue),
1082				ip);
1083	case BLKTRACESETUP:
1084		return blk_trace_setup(sdp->device->request_queue,
1085				       sdp->disk->disk_name,
1086				       MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1087				       NULL,
1088				       (char *)arg);
1089	case BLKTRACESTART:
1090		return blk_trace_startstop(sdp->device->request_queue, 1);
1091	case BLKTRACESTOP:
1092		return blk_trace_startstop(sdp->device->request_queue, 0);
1093	case BLKTRACETEARDOWN:
1094		return blk_trace_remove(sdp->device->request_queue);
1095	case SCSI_IOCTL_GET_IDLUN:
1096	case SCSI_IOCTL_GET_BUS_NUMBER:
1097	case SCSI_IOCTL_PROBE_HOST:
1098	case SG_GET_TRANSFORM:
1099	case SG_SCSI_RESET:
1100		if (atomic_read(&sdp->detaching))
1101			return -ENODEV;
1102		break;
1103	default:
1104		if (read_only)
1105			return -EPERM;	/* don't know so take safe approach */
1106		break;
1107	}
 
 
 
 
 
 
 
 
 
 
1108
1109	result = scsi_ioctl_block_when_processing_errors(sdp->device,
1110			cmd_in, filp->f_flags & O_NDELAY);
1111	if (result)
1112		return result;
1113	return scsi_ioctl(sdp->device, cmd_in, p);
1114}
1115
1116#ifdef CONFIG_COMPAT
1117static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1118{
1119	Sg_device *sdp;
1120	Sg_fd *sfp;
1121	struct scsi_device *sdev;
1122
1123	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1124		return -ENXIO;
1125
1126	sdev = sdp->device;
1127	if (sdev->host->hostt->compat_ioctl) { 
1128		int ret;
1129
1130		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1131
1132		return ret;
1133	}
1134	
1135	return -ENOIOCTLCMD;
1136}
1137#endif
1138
1139static unsigned int
1140sg_poll(struct file *filp, poll_table * wait)
1141{
1142	unsigned int res = 0;
1143	Sg_device *sdp;
1144	Sg_fd *sfp;
1145	Sg_request *srp;
1146	int count = 0;
1147	unsigned long iflags;
1148
1149	sfp = filp->private_data;
1150	if (!sfp)
1151		return POLLERR;
1152	sdp = sfp->parentdp;
1153	if (!sdp)
1154		return POLLERR;
1155	poll_wait(filp, &sfp->read_wait, wait);
1156	read_lock_irqsave(&sfp->rq_list_lock, iflags);
1157	for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1158		/* if any read waiting, flag it */
1159		if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1160			res = POLLIN | POLLRDNORM;
1161		++count;
1162	}
1163	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1164
1165	if (atomic_read(&sdp->detaching))
1166		res |= POLLHUP;
1167	else if (!sfp->cmd_q) {
1168		if (0 == count)
1169			res |= POLLOUT | POLLWRNORM;
1170	} else if (count < SG_MAX_QUEUE)
1171		res |= POLLOUT | POLLWRNORM;
1172	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1173				      "sg_poll: res=0x%x\n", (int) res));
1174	return res;
1175}
1176
1177static int
1178sg_fasync(int fd, struct file *filp, int mode)
1179{
1180	Sg_device *sdp;
1181	Sg_fd *sfp;
1182
1183	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1184		return -ENXIO;
1185	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1186				      "sg_fasync: mode=%d\n", mode));
1187
1188	return fasync_helper(fd, filp, mode, &sfp->async_qp);
1189}
1190
1191static int
1192sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1193{
1194	Sg_fd *sfp;
1195	unsigned long offset, len, sa;
1196	Sg_scatter_hold *rsv_schp;
1197	int k, length;
1198
1199	if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1200		return VM_FAULT_SIGBUS;
1201	rsv_schp = &sfp->reserve;
1202	offset = vmf->pgoff << PAGE_SHIFT;
1203	if (offset >= rsv_schp->bufflen)
1204		return VM_FAULT_SIGBUS;
1205	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1206				      "sg_vma_fault: offset=%lu, scatg=%d\n",
1207				      offset, rsv_schp->k_use_sg));
1208	sa = vma->vm_start;
1209	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1210	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1211		len = vma->vm_end - sa;
1212		len = (len < length) ? len : length;
1213		if (offset < len) {
1214			struct page *page = nth_page(rsv_schp->pages[k],
1215						     offset >> PAGE_SHIFT);
1216			get_page(page);	/* increment page count */
1217			vmf->page = page;
1218			return 0; /* success */
1219		}
1220		sa += len;
1221		offset -= len;
1222	}
1223
1224	return VM_FAULT_SIGBUS;
1225}
1226
1227static const struct vm_operations_struct sg_mmap_vm_ops = {
1228	.fault = sg_vma_fault,
1229};
1230
1231static int
1232sg_mmap(struct file *filp, struct vm_area_struct *vma)
1233{
1234	Sg_fd *sfp;
1235	unsigned long req_sz, len, sa;
1236	Sg_scatter_hold *rsv_schp;
1237	int k, length;
1238
1239	if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))
1240		return -ENXIO;
1241	req_sz = vma->vm_end - vma->vm_start;
1242	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,
1243				      "sg_mmap starting, vm_start=%p, len=%d\n",
1244				      (void *) vma->vm_start, (int) req_sz));
1245	if (vma->vm_pgoff)
1246		return -EINVAL;	/* want no offset */
1247	rsv_schp = &sfp->reserve;
1248	if (req_sz > rsv_schp->bufflen)
1249		return -ENOMEM;	/* cannot map more than reserved buffer */
1250
1251	sa = vma->vm_start;
1252	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1253	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1254		len = vma->vm_end - sa;
1255		len = (len < length) ? len : length;
1256		sa += len;
1257	}
1258
1259	sfp->mmap_called = 1;
1260	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
1261	vma->vm_private_data = sfp;
1262	vma->vm_ops = &sg_mmap_vm_ops;
1263	return 0;
1264}
1265
1266static void
1267sg_rq_end_io_usercontext(struct work_struct *work)
1268{
1269	struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1270	struct sg_fd *sfp = srp->parentfp;
1271
1272	sg_finish_rem_req(srp);
1273	kref_put(&sfp->f_ref, sg_remove_sfp);
1274}
1275
1276/*
1277 * This function is a "bottom half" handler that is called by the mid
1278 * level when a command is completed (or has failed).
1279 */
1280static void
1281sg_rq_end_io(struct request *rq, int uptodate)
1282{
1283	struct sg_request *srp = rq->end_io_data;
1284	Sg_device *sdp;
1285	Sg_fd *sfp;
1286	unsigned long iflags;
1287	unsigned int ms;
1288	char *sense;
1289	int result, resid, done = 1;
1290
1291	if (WARN_ON(srp->done != 0))
1292		return;
1293
1294	sfp = srp->parentfp;
1295	if (WARN_ON(sfp == NULL))
1296		return;
1297
1298	sdp = sfp->parentdp;
1299	if (unlikely(atomic_read(&sdp->detaching)))
1300		pr_info("%s: device detaching\n", __func__);
1301
1302	sense = rq->sense;
1303	result = rq->errors;
1304	resid = rq->resid_len;
1305
1306	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,
1307				      "sg_cmd_done: pack_id=%d, res=0x%x\n",
1308				      srp->header.pack_id, result));
1309	srp->header.resid = resid;
1310	ms = jiffies_to_msecs(jiffies);
1311	srp->header.duration = (ms > srp->header.duration) ?
1312				(ms - srp->header.duration) : 0;
1313	if (0 != result) {
1314		struct scsi_sense_hdr sshdr;
1315
1316		srp->header.status = 0xff & result;
1317		srp->header.masked_status = status_byte(result);
1318		srp->header.msg_status = msg_byte(result);
1319		srp->header.host_status = host_byte(result);
1320		srp->header.driver_status = driver_byte(result);
1321		if ((sdp->sgdebug > 0) &&
1322		    ((CHECK_CONDITION == srp->header.masked_status) ||
1323		     (COMMAND_TERMINATED == srp->header.masked_status)))
1324			__scsi_print_sense(sdp->device, __func__, sense,
1325					   SCSI_SENSE_BUFFERSIZE);
1326
1327		/* Following if statement is a patch supplied by Eric Youngdale */
1328		if (driver_byte(result) != 0
1329		    && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1330		    && !scsi_sense_is_deferred(&sshdr)
1331		    && sshdr.sense_key == UNIT_ATTENTION
1332		    && sdp->device->removable) {
1333			/* Detected possible disc change. Set the bit - this */
1334			/* may be used if there are filesystems using this device */
1335			sdp->device->changed = 1;
1336		}
1337	}
1338	/* Rely on write phase to clean out srp status values, so no "else" */
1339
1340	/*
1341	 * Free the request as soon as it is complete so that its resources
1342	 * can be reused without waiting for userspace to read() the
1343	 * result.  But keep the associated bio (if any) around until
1344	 * blk_rq_unmap_user() can be called from user context.
1345	 */
1346	srp->rq = NULL;
1347	if (rq->cmd != rq->__cmd)
1348		kfree(rq->cmd);
1349	__blk_put_request(rq->q, rq);
1350
1351	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1352	if (unlikely(srp->orphan)) {
1353		if (sfp->keep_orphan)
1354			srp->sg_io_owned = 0;
1355		else
1356			done = 0;
1357	}
1358	srp->done = done;
1359	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1360
1361	if (likely(done)) {
1362		/* Now wake up any sg_read() that is waiting for this
1363		 * packet.
1364		 */
1365		wake_up_interruptible(&sfp->read_wait);
1366		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1367		kref_put(&sfp->f_ref, sg_remove_sfp);
1368	} else {
1369		INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1370		schedule_work(&srp->ew.work);
1371	}
1372}
1373
1374static const struct file_operations sg_fops = {
1375	.owner = THIS_MODULE,
1376	.read = sg_read,
1377	.write = sg_write,
1378	.poll = sg_poll,
1379	.unlocked_ioctl = sg_ioctl,
1380#ifdef CONFIG_COMPAT
1381	.compat_ioctl = sg_compat_ioctl,
1382#endif
1383	.open = sg_open,
1384	.mmap = sg_mmap,
1385	.release = sg_release,
1386	.fasync = sg_fasync,
1387	.llseek = no_llseek,
1388};
1389
1390static struct class *sg_sysfs_class;
1391
1392static int sg_sysfs_valid = 0;
1393
1394static Sg_device *
1395sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
1396{
1397	struct request_queue *q = scsidp->request_queue;
1398	Sg_device *sdp;
1399	unsigned long iflags;
1400	int error;
1401	u32 k;
1402
1403	sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1404	if (!sdp) {
1405		sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "
1406			    "failure\n", __func__);
1407		return ERR_PTR(-ENOMEM);
1408	}
1409
1410	idr_preload(GFP_KERNEL);
 
 
 
 
 
1411	write_lock_irqsave(&sg_index_lock, iflags);
1412
1413	error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
1414	if (error < 0) {
1415		if (error == -ENOSPC) {
1416			sdev_printk(KERN_WARNING, scsidp,
1417				    "Unable to attach sg device type=%d, minor number exceeds %d\n",
1418				    scsidp->type, SG_MAX_DEVS - 1);
1419			error = -ENODEV;
1420		} else {
1421			sdev_printk(KERN_WARNING, scsidp, "%s: idr "
1422				    "allocation Sg_device failure: %d\n",
1423				    __func__, error);
1424		}
1425		goto out_unlock;
1426	}
1427	k = error;
1428
1429	SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,
1430					"sg_alloc: dev=%d \n", k));
 
 
1431	sprintf(disk->disk_name, "sg%d", k);
1432	disk->first_minor = k;
1433	sdp->disk = disk;
1434	sdp->device = scsidp;
1435	mutex_init(&sdp->open_rel_lock);
1436	INIT_LIST_HEAD(&sdp->sfds);
1437	init_waitqueue_head(&sdp->open_wait);
1438	atomic_set(&sdp->detaching, 0);
1439	rwlock_init(&sdp->sfd_lock);
1440	sdp->sg_tablesize = queue_max_segments(q);
1441	sdp->index = k;
1442	kref_init(&sdp->d_ref);
1443	error = 0;
1444
1445out_unlock:
1446	write_unlock_irqrestore(&sg_index_lock, iflags);
1447	idr_preload_end();
1448
 
 
1449	if (error) {
1450		kfree(sdp);
1451		return ERR_PTR(error);
1452	}
1453	return sdp;
 
 
 
 
 
 
 
 
 
1454}
1455
1456static int
1457sg_add_device(struct device *cl_dev, struct class_interface *cl_intf)
1458{
1459	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1460	struct gendisk *disk;
1461	Sg_device *sdp = NULL;
1462	struct cdev * cdev = NULL;
1463	int error;
1464	unsigned long iflags;
1465
1466	disk = alloc_disk(1);
1467	if (!disk) {
1468		pr_warn("%s: alloc_disk failed\n", __func__);
1469		return -ENOMEM;
1470	}
1471	disk->major = SCSI_GENERIC_MAJOR;
1472
1473	error = -ENOMEM;
1474	cdev = cdev_alloc();
1475	if (!cdev) {
1476		pr_warn("%s: cdev_alloc failed\n", __func__);
1477		goto out;
1478	}
1479	cdev->owner = THIS_MODULE;
1480	cdev->ops = &sg_fops;
1481
1482	sdp = sg_alloc(disk, scsidp);
1483	if (IS_ERR(sdp)) {
1484		pr_warn("%s: sg_alloc failed\n", __func__);
1485		error = PTR_ERR(sdp);
1486		goto out;
1487	}
1488
1489	error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1490	if (error)
1491		goto cdev_add_err;
1492
1493	sdp->cdev = cdev;
1494	if (sg_sysfs_valid) {
1495		struct device *sg_class_member;
1496
1497		sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1498						MKDEV(SCSI_GENERIC_MAJOR,
1499						      sdp->index),
1500						sdp, "%s", disk->disk_name);
1501		if (IS_ERR(sg_class_member)) {
1502			pr_err("%s: device_create failed\n", __func__);
 
1503			error = PTR_ERR(sg_class_member);
1504			goto cdev_add_err;
1505		}
1506		error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1507					  &sg_class_member->kobj, "generic");
1508		if (error)
1509			pr_err("%s: unable to make symlink 'generic' back "
1510			       "to sg%d\n", __func__, sdp->index);
1511	} else
1512		pr_warn("%s: sg_sys Invalid\n", __func__);
1513
1514	sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "
1515		    "type %d\n", sdp->index, scsidp->type);
 
1516
1517	dev_set_drvdata(cl_dev, sdp);
1518
1519	return 0;
1520
1521cdev_add_err:
1522	write_lock_irqsave(&sg_index_lock, iflags);
1523	idr_remove(&sg_index_idr, sdp->index);
1524	write_unlock_irqrestore(&sg_index_lock, iflags);
1525	kfree(sdp);
1526
1527out:
1528	put_disk(disk);
1529	if (cdev)
1530		cdev_del(cdev);
1531	return error;
1532}
1533
1534static void
1535sg_device_destroy(struct kref *kref)
1536{
1537	struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1538	unsigned long flags;
1539
1540	/* CAUTION!  Note that the device can still be found via idr_find()
1541	 * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1542	 * any other cleanup.
1543	 */
1544
1545	write_lock_irqsave(&sg_index_lock, flags);
1546	idr_remove(&sg_index_idr, sdp->index);
1547	write_unlock_irqrestore(&sg_index_lock, flags);
1548
1549	SCSI_LOG_TIMEOUT(3,
1550		sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));
 
1551
1552	put_disk(sdp->disk);
1553	kfree(sdp);
1554}
1555
1556static void
1557sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf)
1558{
1559	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1560	Sg_device *sdp = dev_get_drvdata(cl_dev);
1561	unsigned long iflags;
1562	Sg_fd *sfp;
1563	int val;
1564
1565	if (!sdp)
1566		return;
1567	/* want sdp->detaching non-zero as soon as possible */
1568	val = atomic_inc_return(&sdp->detaching);
1569	if (val > 1)
1570		return; /* only want to do following once per device */
1571
1572	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
1573				      "%s\n", __func__));
1574
1575	read_lock_irqsave(&sdp->sfd_lock, iflags);
 
 
1576	list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1577		wake_up_interruptible_all(&sfp->read_wait);
1578		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1579	}
1580	wake_up_interruptible_all(&sdp->open_wait);
1581	read_unlock_irqrestore(&sdp->sfd_lock, iflags);
1582
1583	sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1584	device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1585	cdev_del(sdp->cdev);
1586	sdp->cdev = NULL;
1587
1588	kref_put(&sdp->d_ref, sg_device_destroy);
1589}
1590
1591module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1592module_param_named(def_reserved_size, def_reserved_size, int,
1593		   S_IRUGO | S_IWUSR);
1594module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1595
1596MODULE_AUTHOR("Douglas Gilbert");
1597MODULE_DESCRIPTION("SCSI generic (sg) driver");
1598MODULE_LICENSE("GPL");
1599MODULE_VERSION(SG_VERSION_STR);
1600MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1601
1602MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1603                "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1604MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1605MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1606
1607static int __init
1608init_sg(void)
1609{
1610	int rc;
1611
1612	if (scatter_elem_sz < PAGE_SIZE) {
1613		scatter_elem_sz = PAGE_SIZE;
1614		scatter_elem_sz_prev = scatter_elem_sz;
1615	}
1616	if (def_reserved_size >= 0)
1617		sg_big_buff = def_reserved_size;
1618	else
1619		def_reserved_size = sg_big_buff;
1620
1621	rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 
1622				    SG_MAX_DEVS, "sg");
1623	if (rc)
1624		return rc;
1625        sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1626        if ( IS_ERR(sg_sysfs_class) ) {
1627		rc = PTR_ERR(sg_sysfs_class);
1628		goto err_out;
1629        }
1630	sg_sysfs_valid = 1;
1631	rc = scsi_register_interface(&sg_interface);
1632	if (0 == rc) {
1633#ifdef CONFIG_SCSI_PROC_FS
1634		sg_proc_init();
1635#endif				/* CONFIG_SCSI_PROC_FS */
1636		return 0;
1637	}
1638	class_destroy(sg_sysfs_class);
1639err_out:
1640	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1641	return rc;
1642}
1643
1644static void __exit
1645exit_sg(void)
1646{
1647#ifdef CONFIG_SCSI_PROC_FS
1648	sg_proc_cleanup();
1649#endif				/* CONFIG_SCSI_PROC_FS */
1650	scsi_unregister_interface(&sg_interface);
1651	class_destroy(sg_sysfs_class);
1652	sg_sysfs_valid = 0;
1653	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1654				 SG_MAX_DEVS);
1655	idr_destroy(&sg_index_idr);
1656}
1657
1658static int
1659sg_start_req(Sg_request *srp, unsigned char *cmd)
1660{
1661	int res;
1662	struct request *rq;
1663	Sg_fd *sfp = srp->parentfp;
1664	sg_io_hdr_t *hp = &srp->header;
1665	int dxfer_len = (int) hp->dxfer_len;
1666	int dxfer_dir = hp->dxfer_direction;
1667	unsigned int iov_count = hp->iovec_count;
1668	Sg_scatter_hold *req_schp = &srp->data;
1669	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1670	struct request_queue *q = sfp->parentdp->device->request_queue;
1671	struct rq_map_data *md, map_data;
1672	int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
1673	unsigned char *long_cmdp = NULL;
1674
1675	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1676				      "sg_start_req: dxfer_len=%d\n",
1677				      dxfer_len));
1678
1679	if (hp->cmd_len > BLK_MAX_CDB) {
1680		long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL);
1681		if (!long_cmdp)
1682			return -ENOMEM;
1683	}
1684
1685	/*
1686	 * NOTE
1687	 *
1688	 * With scsi-mq enabled, there are a fixed number of preallocated
1689	 * requests equal in number to shost->can_queue.  If all of the
1690	 * preallocated requests are already in use, then using GFP_ATOMIC with
1691	 * blk_get_request() will return -EWOULDBLOCK, whereas using GFP_KERNEL
1692	 * will cause blk_get_request() to sleep until an active command
1693	 * completes, freeing up a request.  Neither option is ideal, but
1694	 * GFP_KERNEL is the better choice to prevent userspace from getting an
1695	 * unexpected EWOULDBLOCK.
1696	 *
1697	 * With scsi-mq disabled, blk_get_request() with GFP_KERNEL usually
1698	 * does not sleep except under memory pressure.
1699	 */
1700	rq = blk_get_request(q, rw, GFP_KERNEL);
1701	if (IS_ERR(rq)) {
1702		kfree(long_cmdp);
1703		return PTR_ERR(rq);
1704	}
1705
1706	blk_rq_set_block_pc(rq);
 
 
1707
1708	if (hp->cmd_len > BLK_MAX_CDB)
1709		rq->cmd = long_cmdp;
1710	memcpy(rq->cmd, cmd, hp->cmd_len);
 
1711	rq->cmd_len = hp->cmd_len;
 
1712
1713	srp->rq = rq;
1714	rq->end_io_data = srp;
1715	rq->sense = srp->sense_b;
1716	rq->retries = SG_DEFAULT_RETRIES;
1717
1718	if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1719		return 0;
1720
1721	if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1722	    dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1723	    !sfp->parentdp->device->host->unchecked_isa_dma &&
1724	    blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1725		md = NULL;
1726	else
1727		md = &map_data;
1728
1729	if (md) {
1730		if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1731			sg_link_reserve(sfp, srp, dxfer_len);
1732		else {
1733			res = sg_build_indirect(req_schp, sfp, dxfer_len);
1734			if (res)
1735				return res;
1736		}
1737
1738		md->pages = req_schp->pages;
1739		md->page_order = req_schp->page_order;
1740		md->nr_entries = req_schp->k_use_sg;
1741		md->offset = 0;
1742		md->null_mapped = hp->dxferp ? 0 : 1;
1743		if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1744			md->from_user = 1;
1745		else
1746			md->from_user = 0;
1747	}
1748
1749	if (iov_count) {
1750		struct iovec *iov = NULL;
1751		struct iov_iter i;
1752
1753		res = import_iovec(rw, hp->dxferp, iov_count, 0, &iov, &i);
1754		if (res < 0)
1755			return res;
1756
1757		iov_iter_truncate(&i, hp->dxfer_len);
1758		if (!iov_iter_count(&i)) {
1759			kfree(iov);
1760			return -EINVAL;
1761		}
1762
1763		res = blk_rq_map_user_iov(q, rq, md, &i, GFP_ATOMIC);
 
 
1764		kfree(iov);
1765	} else
1766		res = blk_rq_map_user(q, rq, md, hp->dxferp,
1767				      hp->dxfer_len, GFP_ATOMIC);
1768
1769	if (!res) {
1770		srp->bio = rq->bio;
1771
1772		if (!md) {
1773			req_schp->dio_in_use = 1;
1774			hp->info |= SG_INFO_DIRECT_IO;
1775		}
1776	}
1777	return res;
1778}
1779
1780static int
1781sg_finish_rem_req(Sg_request *srp)
1782{
1783	int ret = 0;
1784
1785	Sg_fd *sfp = srp->parentfp;
1786	Sg_scatter_hold *req_schp = &srp->data;
1787
1788	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1789				      "sg_finish_rem_req: res_used=%d\n",
1790				      (int) srp->res_used));
1791	if (srp->bio)
1792		ret = blk_rq_unmap_user(srp->bio);
1793
1794	if (srp->rq) {
1795		if (srp->rq->cmd != srp->rq->__cmd)
1796			kfree(srp->rq->cmd);
 
1797		blk_put_request(srp->rq);
1798	}
1799
1800	if (srp->res_used)
1801		sg_unlink_reserve(sfp, srp);
1802	else
1803		sg_remove_scat(sfp, req_schp);
1804
1805	sg_remove_request(sfp, srp);
1806
1807	return ret;
1808}
1809
1810static int
1811sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1812{
1813	int sg_bufflen = tablesize * sizeof(struct page *);
1814	gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1815
1816	schp->pages = kzalloc(sg_bufflen, gfp_flags);
1817	if (!schp->pages)
1818		return -ENOMEM;
1819	schp->sglist_len = sg_bufflen;
1820	return tablesize;	/* number of scat_gath elements allocated */
1821}
1822
1823static int
1824sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1825{
1826	int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1827	int sg_tablesize = sfp->parentdp->sg_tablesize;
1828	int blk_size = buff_size, order;
1829	gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1830
1831	if (blk_size < 0)
1832		return -EFAULT;
1833	if (0 == blk_size)
1834		++blk_size;	/* don't know why */
1835	/* round request up to next highest SG_SECTOR_SZ byte boundary */
1836	blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1837	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1838		"sg_build_indirect: buff_size=%d, blk_size=%d\n",
1839		buff_size, blk_size));
1840
1841	/* N.B. ret_sz carried into this block ... */
1842	mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1843	if (mx_sc_elems < 0)
1844		return mx_sc_elems;	/* most likely -ENOMEM */
1845
1846	num = scatter_elem_sz;
1847	if (unlikely(num != scatter_elem_sz_prev)) {
1848		if (num < PAGE_SIZE) {
1849			scatter_elem_sz = PAGE_SIZE;
1850			scatter_elem_sz_prev = PAGE_SIZE;
1851		} else
1852			scatter_elem_sz_prev = num;
1853	}
1854
1855	if (sfp->low_dma)
1856		gfp_mask |= GFP_DMA;
1857
1858	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1859		gfp_mask |= __GFP_ZERO;
1860
1861	order = get_order(num);
1862retry:
1863	ret_sz = 1 << (PAGE_SHIFT + order);
1864
1865	for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1866	     k++, rem_sz -= ret_sz) {
1867
1868		num = (rem_sz > scatter_elem_sz_prev) ?
1869			scatter_elem_sz_prev : rem_sz;
1870
1871		schp->pages[k] = alloc_pages(gfp_mask, order);
1872		if (!schp->pages[k])
1873			goto out;
1874
1875		if (num == scatter_elem_sz_prev) {
1876			if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1877				scatter_elem_sz = ret_sz;
1878				scatter_elem_sz_prev = ret_sz;
1879			}
1880		}
1881
1882		SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1883				 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",
1884				 k, num, ret_sz));
1885	}		/* end of for loop */
1886
1887	schp->page_order = order;
1888	schp->k_use_sg = k;
1889	SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,
1890			 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",
1891			 k, rem_sz));
1892
1893	schp->bufflen = blk_size;
1894	if (rem_sz > 0)	/* must have failed */
1895		return -ENOMEM;
1896	return 0;
1897out:
1898	for (i = 0; i < k; i++)
1899		__free_pages(schp->pages[i], order);
1900
1901	if (--order >= 0)
1902		goto retry;
1903
1904	return -ENOMEM;
1905}
1906
1907static void
1908sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)
1909{
1910	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1911			 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
1912	if (schp->pages && schp->sglist_len > 0) {
1913		if (!schp->dio_in_use) {
1914			int k;
1915
1916			for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1917				SCSI_LOG_TIMEOUT(5,
1918					sg_printk(KERN_INFO, sfp->parentdp,
1919					"sg_remove_scat: k=%d, pg=0x%p\n",
1920					k, schp->pages[k]));
1921				__free_pages(schp->pages[k], schp->page_order);
1922			}
1923
1924			kfree(schp->pages);
1925		}
1926	}
1927	memset(schp, 0, sizeof (*schp));
1928}
1929
1930static int
1931sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1932{
1933	Sg_scatter_hold *schp = &srp->data;
1934	int k, num;
1935
1936	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
1937			 "sg_read_oxfer: num_read_xfer=%d\n",
1938			 num_read_xfer));
1939	if ((!outp) || (num_read_xfer <= 0))
1940		return 0;
1941
1942	num = 1 << (PAGE_SHIFT + schp->page_order);
1943	for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1944		if (num > num_read_xfer) {
1945			if (__copy_to_user(outp, page_address(schp->pages[k]),
1946					   num_read_xfer))
1947				return -EFAULT;
1948			break;
1949		} else {
1950			if (__copy_to_user(outp, page_address(schp->pages[k]),
1951					   num))
1952				return -EFAULT;
1953			num_read_xfer -= num;
1954			if (num_read_xfer <= 0)
1955				break;
1956			outp += num;
1957		}
1958	}
1959
1960	return 0;
1961}
1962
1963static void
1964sg_build_reserve(Sg_fd * sfp, int req_size)
1965{
1966	Sg_scatter_hold *schp = &sfp->reserve;
1967
1968	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1969			 "sg_build_reserve: req_size=%d\n", req_size));
1970	do {
1971		if (req_size < PAGE_SIZE)
1972			req_size = PAGE_SIZE;
1973		if (0 == sg_build_indirect(schp, sfp, req_size))
1974			return;
1975		else
1976			sg_remove_scat(sfp, schp);
1977		req_size >>= 1;	/* divide by 2 */
1978	} while (req_size > (PAGE_SIZE / 2));
1979}
1980
1981static void
1982sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1983{
1984	Sg_scatter_hold *req_schp = &srp->data;
1985	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1986	int k, num, rem;
1987
1988	srp->res_used = 1;
1989	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,
1990			 "sg_link_reserve: size=%d\n", size));
1991	rem = size;
1992
1993	num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1994	for (k = 0; k < rsv_schp->k_use_sg; k++) {
1995		if (rem <= num) {
1996			req_schp->k_use_sg = k + 1;
1997			req_schp->sglist_len = rsv_schp->sglist_len;
1998			req_schp->pages = rsv_schp->pages;
1999
2000			req_schp->bufflen = size;
2001			req_schp->page_order = rsv_schp->page_order;
2002			break;
2003		} else
2004			rem -= num;
2005	}
2006
2007	if (k >= rsv_schp->k_use_sg)
2008		SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,
2009				 "sg_link_reserve: BAD size\n"));
2010}
2011
2012static void
2013sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
2014{
2015	Sg_scatter_hold *req_schp = &srp->data;
2016
2017	SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,
2018				      "sg_unlink_reserve: req->k_use_sg=%d\n",
2019				      (int) req_schp->k_use_sg));
2020	req_schp->k_use_sg = 0;
2021	req_schp->bufflen = 0;
2022	req_schp->pages = NULL;
2023	req_schp->page_order = 0;
2024	req_schp->sglist_len = 0;
2025	sfp->save_scat_len = 0;
2026	srp->res_used = 0;
2027}
2028
2029static Sg_request *
2030sg_get_rq_mark(Sg_fd * sfp, int pack_id)
2031{
2032	Sg_request *resp;
2033	unsigned long iflags;
2034
2035	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2036	for (resp = sfp->headrp; resp; resp = resp->nextrp) {
2037		/* look for requests that are ready + not SG_IO owned */
2038		if ((1 == resp->done) && (!resp->sg_io_owned) &&
2039		    ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
2040			resp->done = 2;	/* guard against other readers */
2041			break;
2042		}
2043	}
2044	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2045	return resp;
2046}
2047
2048/* always adds to end of list */
2049static Sg_request *
2050sg_add_request(Sg_fd * sfp)
2051{
2052	int k;
2053	unsigned long iflags;
2054	Sg_request *resp;
2055	Sg_request *rp = sfp->req_arr;
2056
2057	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2058	resp = sfp->headrp;
2059	if (!resp) {
2060		memset(rp, 0, sizeof (Sg_request));
2061		rp->parentfp = sfp;
2062		resp = rp;
2063		sfp->headrp = resp;
2064	} else {
2065		if (0 == sfp->cmd_q)
2066			resp = NULL;	/* command queuing disallowed */
2067		else {
2068			for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
2069				if (!rp->parentfp)
2070					break;
2071			}
2072			if (k < SG_MAX_QUEUE) {
2073				memset(rp, 0, sizeof (Sg_request));
2074				rp->parentfp = sfp;
2075				while (resp->nextrp)
2076					resp = resp->nextrp;
2077				resp->nextrp = rp;
2078				resp = rp;
2079			} else
2080				resp = NULL;
2081		}
2082	}
2083	if (resp) {
2084		resp->nextrp = NULL;
2085		resp->header.duration = jiffies_to_msecs(jiffies);
2086	}
2087	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2088	return resp;
2089}
2090
2091/* Return of 1 for found; 0 for not found */
2092static int
2093sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2094{
2095	Sg_request *prev_rp;
2096	Sg_request *rp;
2097	unsigned long iflags;
2098	int res = 0;
2099
2100	if ((!sfp) || (!srp) || (!sfp->headrp))
2101		return res;
2102	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2103	prev_rp = sfp->headrp;
2104	if (srp == prev_rp) {
2105		sfp->headrp = prev_rp->nextrp;
2106		prev_rp->parentfp = NULL;
2107		res = 1;
2108	} else {
2109		while ((rp = prev_rp->nextrp)) {
2110			if (srp == rp) {
2111				prev_rp->nextrp = rp->nextrp;
2112				rp->parentfp = NULL;
2113				res = 1;
2114				break;
2115			}
2116			prev_rp = rp;
2117		}
2118	}
2119	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2120	return res;
2121}
2122
2123static Sg_fd *
2124sg_add_sfp(Sg_device * sdp)
2125{
2126	Sg_fd *sfp;
2127	unsigned long iflags;
2128	int bufflen;
2129
2130	sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2131	if (!sfp)
2132		return ERR_PTR(-ENOMEM);
2133
2134	init_waitqueue_head(&sfp->read_wait);
2135	rwlock_init(&sfp->rq_list_lock);
2136
2137	kref_init(&sfp->f_ref);
2138	sfp->timeout = SG_DEFAULT_TIMEOUT;
2139	sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2140	sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2141	sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2142	    sdp->device->host->unchecked_isa_dma : 1;
2143	sfp->cmd_q = SG_DEF_COMMAND_Q;
2144	sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2145	sfp->parentdp = sdp;
2146	write_lock_irqsave(&sdp->sfd_lock, iflags);
2147	if (atomic_read(&sdp->detaching)) {
2148		write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2149		return ERR_PTR(-ENODEV);
2150	}
2151	list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2152	write_unlock_irqrestore(&sdp->sfd_lock, iflags);
2153	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2154				      "sg_add_sfp: sfp=0x%p\n", sfp));
2155	if (unlikely(sg_big_buff != def_reserved_size))
2156		sg_big_buff = def_reserved_size;
2157
2158	bufflen = min_t(int, sg_big_buff,
2159			max_sectors_bytes(sdp->device->request_queue));
2160	sg_build_reserve(sfp, bufflen);
2161	SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,
2162				      "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",
2163				      sfp->reserve.bufflen,
2164				      sfp->reserve.k_use_sg));
2165
2166	kref_get(&sdp->d_ref);
2167	__module_get(THIS_MODULE);
2168	return sfp;
2169}
2170
2171static void
2172sg_remove_sfp_usercontext(struct work_struct *work)
2173{
2174	struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2175	struct sg_device *sdp = sfp->parentdp;
2176
2177	/* Cleanup any responses which were never read(). */
2178	while (sfp->headrp)
2179		sg_finish_rem_req(sfp->headrp);
2180
2181	if (sfp->reserve.bufflen > 0) {
2182		SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2183				"sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2184				(int) sfp->reserve.bufflen,
2185				(int) sfp->reserve.k_use_sg));
2186		sg_remove_scat(sfp, &sfp->reserve);
2187	}
2188
2189	SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,
2190			"sg_remove_sfp: sfp=0x%p\n", sfp));
 
 
2191	kfree(sfp);
2192
2193	scsi_device_put(sdp->device);
2194	kref_put(&sdp->d_ref, sg_device_destroy);
2195	module_put(THIS_MODULE);
2196}
2197
2198static void
2199sg_remove_sfp(struct kref *kref)
2200{
2201	struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2202	struct sg_device *sdp = sfp->parentdp;
2203	unsigned long iflags;
2204
2205	write_lock_irqsave(&sdp->sfd_lock, iflags);
2206	list_del(&sfp->sfd_siblings);
2207	write_unlock_irqrestore(&sdp->sfd_lock, iflags);
 
2208
2209	INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2210	schedule_work(&sfp->ew.work);
2211}
2212
2213static int
2214sg_res_in_use(Sg_fd * sfp)
2215{
2216	const Sg_request *srp;
2217	unsigned long iflags;
2218
2219	read_lock_irqsave(&sfp->rq_list_lock, iflags);
2220	for (srp = sfp->headrp; srp; srp = srp->nextrp)
2221		if (srp->res_used)
2222			break;
2223	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2224	return srp ? 1 : 0;
2225}
2226
2227#ifdef CONFIG_SCSI_PROC_FS
2228static int
2229sg_idr_max_id(int id, void *p, void *data)
2230{
2231	int *k = data;
2232
2233	if (*k < id)
2234		*k = id;
2235
2236	return 0;
2237}
2238
2239static int
2240sg_last_dev(void)
2241{
2242	int k = -1;
2243	unsigned long iflags;
2244
2245	read_lock_irqsave(&sg_index_lock, iflags);
2246	idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2247	read_unlock_irqrestore(&sg_index_lock, iflags);
2248	return k + 1;		/* origin 1 */
2249}
2250#endif
2251
2252/* must be called with sg_index_lock held */
2253static Sg_device *sg_lookup_dev(int dev)
2254{
2255	return idr_find(&sg_index_idr, dev);
2256}
2257
2258static Sg_device *
2259sg_get_dev(int dev)
2260{
2261	struct sg_device *sdp;
2262	unsigned long flags;
2263
2264	read_lock_irqsave(&sg_index_lock, flags);
2265	sdp = sg_lookup_dev(dev);
2266	if (!sdp)
2267		sdp = ERR_PTR(-ENXIO);
2268	else if (atomic_read(&sdp->detaching)) {
2269		/* If sdp->detaching, then the refcount may already be 0, in
2270		 * which case it would be a bug to do kref_get().
2271		 */
2272		sdp = ERR_PTR(-ENODEV);
2273	} else
2274		kref_get(&sdp->d_ref);
2275	read_unlock_irqrestore(&sg_index_lock, flags);
2276
2277	return sdp;
2278}
2279
 
 
 
 
 
2280#ifdef CONFIG_SCSI_PROC_FS
2281
2282static struct proc_dir_entry *sg_proc_sgp = NULL;
2283
2284static char sg_proc_sg_dirname[] = "scsi/sg";
2285
2286static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2287
2288static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2289static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2290			          size_t count, loff_t *off);
2291static const struct file_operations adio_fops = {
2292	.owner = THIS_MODULE,
2293	.open = sg_proc_single_open_adio,
2294	.read = seq_read,
2295	.llseek = seq_lseek,
2296	.write = sg_proc_write_adio,
2297	.release = single_release,
2298};
2299
2300static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2301static ssize_t sg_proc_write_dressz(struct file *filp, 
2302		const char __user *buffer, size_t count, loff_t *off);
2303static const struct file_operations dressz_fops = {
2304	.owner = THIS_MODULE,
2305	.open = sg_proc_single_open_dressz,
2306	.read = seq_read,
2307	.llseek = seq_lseek,
2308	.write = sg_proc_write_dressz,
2309	.release = single_release,
2310};
2311
2312static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2313static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2314static const struct file_operations version_fops = {
2315	.owner = THIS_MODULE,
2316	.open = sg_proc_single_open_version,
2317	.read = seq_read,
2318	.llseek = seq_lseek,
2319	.release = single_release,
2320};
2321
2322static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2323static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2324static const struct file_operations devhdr_fops = {
2325	.owner = THIS_MODULE,
2326	.open = sg_proc_single_open_devhdr,
2327	.read = seq_read,
2328	.llseek = seq_lseek,
2329	.release = single_release,
2330};
2331
2332static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2333static int sg_proc_open_dev(struct inode *inode, struct file *file);
2334static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2335static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2336static void dev_seq_stop(struct seq_file *s, void *v);
2337static const struct file_operations dev_fops = {
2338	.owner = THIS_MODULE,
2339	.open = sg_proc_open_dev,
2340	.read = seq_read,
2341	.llseek = seq_lseek,
2342	.release = seq_release,
2343};
2344static const struct seq_operations dev_seq_ops = {
2345	.start = dev_seq_start,
2346	.next  = dev_seq_next,
2347	.stop  = dev_seq_stop,
2348	.show  = sg_proc_seq_show_dev,
2349};
2350
2351static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2352static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2353static const struct file_operations devstrs_fops = {
2354	.owner = THIS_MODULE,
2355	.open = sg_proc_open_devstrs,
2356	.read = seq_read,
2357	.llseek = seq_lseek,
2358	.release = seq_release,
2359};
2360static const struct seq_operations devstrs_seq_ops = {
2361	.start = dev_seq_start,
2362	.next  = dev_seq_next,
2363	.stop  = dev_seq_stop,
2364	.show  = sg_proc_seq_show_devstrs,
2365};
2366
2367static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2368static int sg_proc_open_debug(struct inode *inode, struct file *file);
2369static const struct file_operations debug_fops = {
2370	.owner = THIS_MODULE,
2371	.open = sg_proc_open_debug,
2372	.read = seq_read,
2373	.llseek = seq_lseek,
2374	.release = seq_release,
2375};
2376static const struct seq_operations debug_seq_ops = {
2377	.start = dev_seq_start,
2378	.next  = dev_seq_next,
2379	.stop  = dev_seq_stop,
2380	.show  = sg_proc_seq_show_debug,
2381};
2382
2383
2384struct sg_proc_leaf {
2385	const char * name;
2386	const struct file_operations * fops;
2387};
2388
2389static const struct sg_proc_leaf sg_proc_leaf_arr[] = {
2390	{"allow_dio", &adio_fops},
2391	{"debug", &debug_fops},
2392	{"def_reserved_size", &dressz_fops},
2393	{"device_hdr", &devhdr_fops},
2394	{"devices", &dev_fops},
2395	{"device_strs", &devstrs_fops},
2396	{"version", &version_fops}
2397};
2398
2399static int
2400sg_proc_init(void)
2401{
 
2402	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2403	int k;
2404
2405	sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2406	if (!sg_proc_sgp)
2407		return 1;
2408	for (k = 0; k < num_leaves; ++k) {
2409		const struct sg_proc_leaf *leaf = &sg_proc_leaf_arr[k];
2410		umode_t mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2411		proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2412	}
2413	return 0;
2414}
2415
2416static void
2417sg_proc_cleanup(void)
2418{
2419	int k;
2420	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2421
2422	if (!sg_proc_sgp)
2423		return;
2424	for (k = 0; k < num_leaves; ++k)
2425		remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2426	remove_proc_entry(sg_proc_sg_dirname, NULL);
2427}
2428
2429
2430static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2431{
2432	seq_printf(s, "%d\n", *((int *)s->private));
2433	return 0;
2434}
2435
2436static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2437{
2438	return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2439}
2440
2441static ssize_t 
2442sg_proc_write_adio(struct file *filp, const char __user *buffer,
2443		   size_t count, loff_t *off)
2444{
2445	int err;
2446	unsigned long num;
2447
2448	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2449		return -EACCES;
2450	err = kstrtoul_from_user(buffer, count, 0, &num);
2451	if (err)
2452		return err;
2453	sg_allow_dio = num ? 1 : 0;
 
2454	return count;
2455}
2456
2457static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2458{
2459	return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2460}
2461
2462static ssize_t 
2463sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2464		     size_t count, loff_t *off)
2465{
2466	int err;
2467	unsigned long k = ULONG_MAX;
 
2468
2469	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2470		return -EACCES;
2471
2472	err = kstrtoul_from_user(buffer, count, 0, &k);
2473	if (err)
2474		return err;
 
2475	if (k <= 1048576) {	/* limit "big buff" to 1 MB */
2476		sg_big_buff = k;
2477		return count;
2478	}
2479	return -ERANGE;
2480}
2481
2482static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2483{
2484	seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2485		   sg_version_date);
2486	return 0;
2487}
2488
2489static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2490{
2491	return single_open(file, sg_proc_seq_show_version, NULL);
2492}
2493
2494static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2495{
2496	seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");
 
2497	return 0;
2498}
2499
2500static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2501{
2502	return single_open(file, sg_proc_seq_show_devhdr, NULL);
2503}
2504
2505struct sg_proc_deviter {
2506	loff_t	index;
2507	size_t	max;
2508};
2509
2510static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2511{
2512	struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2513
2514	s->private = it;
2515	if (! it)
2516		return NULL;
2517
2518	it->index = *pos;
2519	it->max = sg_last_dev();
2520	if (it->index >= it->max)
2521		return NULL;
2522	return it;
2523}
2524
2525static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2526{
2527	struct sg_proc_deviter * it = s->private;
2528
2529	*pos = ++it->index;
2530	return (it->index < it->max) ? it : NULL;
2531}
2532
2533static void dev_seq_stop(struct seq_file *s, void *v)
2534{
2535	kfree(s->private);
2536}
2537
2538static int sg_proc_open_dev(struct inode *inode, struct file *file)
2539{
2540        return seq_open(file, &dev_seq_ops);
2541}
2542
2543static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2544{
2545	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2546	Sg_device *sdp;
2547	struct scsi_device *scsidp;
2548	unsigned long iflags;
2549
2550	read_lock_irqsave(&sg_index_lock, iflags);
2551	sdp = it ? sg_lookup_dev(it->index) : NULL;
2552	if ((NULL == sdp) || (NULL == sdp->device) ||
2553	    (atomic_read(&sdp->detaching)))
2554		seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2555	else {
2556		scsidp = sdp->device;
2557		seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",
2558			      scsidp->host->host_no, scsidp->channel,
2559			      scsidp->id, scsidp->lun, (int) scsidp->type,
2560			      1,
2561			      (int) scsidp->queue_depth,
2562			      (int) atomic_read(&scsidp->device_busy),
2563			      (int) scsi_device_online(scsidp));
2564	}
 
2565	read_unlock_irqrestore(&sg_index_lock, iflags);
2566	return 0;
2567}
2568
2569static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2570{
2571        return seq_open(file, &devstrs_seq_ops);
2572}
2573
2574static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2575{
2576	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2577	Sg_device *sdp;
2578	struct scsi_device *scsidp;
2579	unsigned long iflags;
2580
2581	read_lock_irqsave(&sg_index_lock, iflags);
2582	sdp = it ? sg_lookup_dev(it->index) : NULL;
2583	scsidp = sdp ? sdp->device : NULL;
2584	if (sdp && scsidp && (!atomic_read(&sdp->detaching)))
2585		seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2586			   scsidp->vendor, scsidp->model, scsidp->rev);
2587	else
2588		seq_puts(s, "<no active device>\n");
2589	read_unlock_irqrestore(&sg_index_lock, iflags);
2590	return 0;
2591}
2592
2593/* must be called while holding sg_index_lock */
2594static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2595{
2596	int k, m, new_interface, blen, usg;
2597	Sg_request *srp;
2598	Sg_fd *fp;
2599	const sg_io_hdr_t *hp;
2600	const char * cp;
2601	unsigned int ms;
2602
2603	k = 0;
2604	list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2605		k++;
2606		read_lock(&fp->rq_list_lock); /* irqs already disabled */
2607		seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2608			   "(res)sgat=%d low_dma=%d\n", k,
2609			   jiffies_to_msecs(fp->timeout),
2610			   fp->reserve.bufflen,
2611			   (int) fp->reserve.k_use_sg,
2612			   (int) fp->low_dma);
2613		seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",
2614			   (int) fp->cmd_q, (int) fp->force_packid,
2615			   (int) fp->keep_orphan);
2616		for (m = 0, srp = fp->headrp;
2617				srp != NULL;
2618				++m, srp = srp->nextrp) {
2619			hp = &srp->header;
2620			new_interface = (hp->interface_id == '\0') ? 0 : 1;
2621			if (srp->res_used) {
2622				if (new_interface && 
2623				    (SG_FLAG_MMAP_IO & hp->flags))
2624					cp = "     mmap>> ";
2625				else
2626					cp = "     rb>> ";
2627			} else {
2628				if (SG_INFO_DIRECT_IO_MASK & hp->info)
2629					cp = "     dio>> ";
2630				else
2631					cp = "     ";
2632			}
2633			seq_puts(s, cp);
2634			blen = srp->data.bufflen;
2635			usg = srp->data.k_use_sg;
2636			seq_puts(s, srp->done ?
2637				 ((1 == srp->done) ?  "rcv:" : "fin:")
2638				  : "act:");
2639			seq_printf(s, " id=%d blen=%d",
2640				   srp->header.pack_id, blen);
2641			if (srp->done)
2642				seq_printf(s, " dur=%d", hp->duration);
2643			else {
2644				ms = jiffies_to_msecs(jiffies);
2645				seq_printf(s, " t_o/elap=%d/%d",
2646					(new_interface ? hp->timeout :
2647						  jiffies_to_msecs(fp->timeout)),
2648					(ms > hp->duration ? ms - hp->duration : 0));
2649			}
2650			seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2651				   (int) srp->data.cmd_opcode);
2652		}
2653		if (0 == m)
2654			seq_puts(s, "     No requests active\n");
2655		read_unlock(&fp->rq_list_lock);
2656	}
2657}
2658
2659static int sg_proc_open_debug(struct inode *inode, struct file *file)
2660{
2661        return seq_open(file, &debug_seq_ops);
2662}
2663
2664static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2665{
2666	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2667	Sg_device *sdp;
2668	unsigned long iflags;
2669
2670	if (it && (0 == it->index))
2671		seq_printf(s, "max_active_device=%d  def_reserved_size=%d\n",
2672			   (int)it->max, sg_big_buff);
 
 
2673
2674	read_lock_irqsave(&sg_index_lock, iflags);
2675	sdp = it ? sg_lookup_dev(it->index) : NULL;
2676	if (NULL == sdp)
2677		goto skip;
2678	read_lock(&sdp->sfd_lock);
2679	if (!list_empty(&sdp->sfds)) {
2680		seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2681		if (atomic_read(&sdp->detaching))
2682			seq_puts(s, "detaching pending close ");
2683		else if (sdp->device) {
2684			struct scsi_device *scsidp = sdp->device;
2685
2686			seq_printf(s, "%d:%d:%d:%llu   em=%d",
2687				   scsidp->host->host_no,
2688				   scsidp->channel, scsidp->id,
2689				   scsidp->lun,
2690				   scsidp->host->hostt->emulated);
2691		}
2692		seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",
2693			   sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);
2694		sg_proc_debug_helper(s, sdp);
2695	}
2696	read_unlock(&sdp->sfd_lock);
2697skip:
2698	read_unlock_irqrestore(&sg_index_lock, iflags);
2699	return 0;
2700}
2701
2702#endif				/* CONFIG_SCSI_PROC_FS */
2703
2704module_init(init_sg);
2705module_exit(exit_sg);
v3.1
   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
  21static 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/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/mutex.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>
  65static char *sg_version_date = "20061027";
  66
  67static int sg_proc_init(void);
  68static void sg_proc_cleanup(void);
  69#endif
  70
  71#define SG_ALLOW_DIO_DEF 0
  72
  73#define SG_MAX_DEVS 32768
  74
  75/*
  76 * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d)
  77 * Then when using 32 bit integers x * m may overflow during the calculation.
  78 * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m
  79 * calculates the same, but prevents the overflow when both m and d
  80 * are "small" numbers (like HZ and USER_HZ).
  81 * Of course an overflow is inavoidable if the result of muldiv doesn't fit
  82 * in 32 bits.
  83 */
  84#define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL))
  85
  86#define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)
  87
  88int 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).] */
  95static int def_reserved_size = -1;	/* picks up init parameter */
  96static int sg_allow_dio = SG_ALLOW_DIO_DEF;
  97
  98static int scatter_elem_sz = SG_SCATTER_SZ;
  99static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 100
 101#define SG_SECTOR_SZ 512
 102
 103static int sg_add(struct device *, struct class_interface *);
 104static void sg_remove(struct device *, struct class_interface *);
 105
 106static DEFINE_MUTEX(sg_mutex);
 107
 108static DEFINE_IDR(sg_index_idr);
 109static DEFINE_RWLOCK(sg_index_lock);	/* Also used to lock
 110							   file descriptor list for device */
 111
 112static struct class_interface sg_interface = {
 113	.add_dev	= sg_add,
 114	.remove_dev	= sg_remove,
 115};
 116
 117typedef 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	struct page **pages;
 122	int page_order;
 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
 127struct sg_device;		/* forward declarations */
 128struct sg_fd;
 129
 130typedef 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	struct request *rq;
 141	struct bio *bio;
 142	struct execute_work ew;
 143} Sg_request;
 144
 145typedef struct sg_fd {		/* holds the state of a file descriptor */
 146	struct list_head sfd_siblings;
 147	struct sg_device *parentdp;	/* owning device */
 148	wait_queue_head_t read_wait;	/* queue read until command done */
 149	rwlock_t rq_list_lock;	/* protect access to list in req_arr */
 150	int timeout;		/* defaults to SG_DEFAULT_TIMEOUT      */
 151	int timeout_user;	/* defaults to SG_DEFAULT_TIMEOUT_USER */
 152	Sg_scatter_hold reserve;	/* buffer held for this file descriptor */
 153	unsigned save_scat_len;	/* original length of trunc. scat. element */
 154	Sg_request *headrp;	/* head of request slist, NULL->empty */
 155	struct fasync_struct *async_qp;	/* used by asynchronous notification */
 156	Sg_request req_arr[SG_MAX_QUEUE];	/* used as singly-linked list */
 157	char low_dma;		/* as in parent but possibly overridden to 1 */
 158	char force_packid;	/* 1 -> pack_id input to read(), 0 -> ignored */
 159	volatile char closed;	/* 1 -> fd closed but request(s) outstanding */
 160	char cmd_q;		/* 1 -> allow command queuing, 0 -> don't */
 161	char next_cmd_len;	/* 0 -> automatic (def), >0 -> use on next write() */
 162	char keep_orphan;	/* 0 -> drop orphan (def), 1 -> keep for read() */
 163	char mmap_called;	/* 0 -> mmap() never called on this fd */
 164	struct kref f_ref;
 165	struct execute_work ew;
 166} Sg_fd;
 167
 168typedef struct sg_device { /* holds the state of each scsi generic device */
 169	struct scsi_device *device;
 170	wait_queue_head_t o_excl_wait;	/* queue open() when O_EXCL in use */
 
 171	int sg_tablesize;	/* adapter's max scatter-gather table size */
 172	u32 index;		/* device index number */
 173	struct list_head sfds;
 174	volatile char detached;	/* 0->attached, 1->detached pending removal */
 175	volatile char exclude;	/* opened for exclusive access */
 
 
 176	char sgdebug;		/* 0->off, 1->sense, 9->dump dev, 10-> all devs */
 177	struct gendisk *disk;
 178	struct cdev * cdev;	/* char_dev [sysfs: /sys/cdev/major/sg<n>] */
 179	struct kref d_ref;
 180} Sg_device;
 181
 182/* tasklet or soft irq callback */
 183static void sg_rq_end_io(struct request *rq, int uptodate);
 184static int sg_start_req(Sg_request *srp, unsigned char *cmd);
 185static int sg_finish_rem_req(Sg_request * srp);
 186static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size);
 187static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count,
 188			   Sg_request * srp);
 189static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
 190			const char __user *buf, size_t count, int blocking,
 191			int read_only, int sg_io_owned, Sg_request **o_srp);
 192static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
 193			   unsigned char *cmnd, int timeout, int blocking);
 194static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 195static void sg_remove_scat(Sg_scatter_hold * schp);
 196static void sg_build_reserve(Sg_fd * sfp, int req_size);
 197static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
 198static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
 199static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
 200static void sg_remove_sfp(struct kref *);
 201static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
 202static Sg_request *sg_add_request(Sg_fd * sfp);
 203static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);
 204static int sg_res_in_use(Sg_fd * sfp);
 205static Sg_device *sg_get_dev(int dev);
 206static void sg_put_dev(Sg_device *sdp);
 207
 208#define SZ_SG_HEADER sizeof(struct sg_header)
 209#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 210#define SZ_SG_IOVEC sizeof(sg_iovec_t)
 211#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 212
 
 
 
 
 213static int sg_allow_access(struct file *filp, unsigned char *cmd)
 214{
 215	struct sg_fd *sfp = filp->private_data;
 216
 217	if (sfp->parentdp->device->type == TYPE_SCANNER)
 218		return 0;
 219
 220	return blk_verify_command(cmd, filp->f_mode & FMODE_WRITE);
 221}
 222
 223static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 224sg_open(struct inode *inode, struct file *filp)
 225{
 226	int dev = iminor(inode);
 227	int flags = filp->f_flags;
 228	struct request_queue *q;
 229	Sg_device *sdp;
 230	Sg_fd *sfp;
 231	int res;
 232	int retval;
 233
 234	mutex_lock(&sg_mutex);
 235	nonseekable_open(inode, filp);
 236	SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 
 237	sdp = sg_get_dev(dev);
 238	if (IS_ERR(sdp)) {
 239		retval = PTR_ERR(sdp);
 240		sdp = NULL;
 241		goto sg_put;
 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		goto sg_put;
 249
 250	retval = scsi_autopm_get_device(sdp->device);
 251	if (retval)
 252		goto sdp_put;
 253
 
 
 
 254	if (!((flags & O_NONBLOCK) ||
 255	      scsi_block_when_processing_errors(sdp->device))) {
 256		retval = -ENXIO;
 257		/* we are in error recovery for this device */
 258		goto error_out;
 259	}
 260
 261	if (flags & O_EXCL) {
 262		if (O_RDONLY == (flags & O_ACCMODE)) {
 263			retval = -EPERM; /* Can't lock it with read only access */
 264			goto error_out;
 265		}
 266		if (!list_empty(&sdp->sfds) && (flags & O_NONBLOCK)) {
 267			retval = -EBUSY;
 268			goto error_out;
 269		}
 270		res = 0;
 271		__wait_event_interruptible(sdp->o_excl_wait,
 272					   ((!list_empty(&sdp->sfds) || sdp->exclude) ? 0 : (sdp->exclude = 1)), res);
 273		if (res) {
 274			retval = res;	/* -ERESTARTSYS because signal hit process */
 275			goto error_out;
 276		}
 277	} else if (sdp->exclude) {	/* some other fd has an exclusive lock on dev */
 278		if (flags & O_NONBLOCK) {
 279			retval = -EBUSY;
 280			goto error_out;
 281		}
 282		res = 0;
 283		__wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude),
 284					   res);
 285		if (res) {
 286			retval = res;	/* -ERESTARTSYS because signal hit process */
 287			goto error_out;
 288		}
 
 
 
 
 289	}
 290	if (sdp->detached) {
 291		retval = -ENODEV;
 292		goto error_out;
 293	}
 294	if (list_empty(&sdp->sfds)) {	/* no existing opens on this device */
 
 295		sdp->sgdebug = 0;
 296		q = sdp->device->request_queue;
 297		sdp->sg_tablesize = queue_max_segments(q);
 298	}
 299	if ((sfp = sg_add_sfp(sdp, dev)))
 300		filp->private_data = sfp;
 301	else {
 302		if (flags & O_EXCL) {
 303			sdp->exclude = 0;	/* undo if error */
 304			wake_up_interruptible(&sdp->o_excl_wait);
 305		}
 306		retval = -ENOMEM;
 307		goto error_out;
 308	}
 
 
 
 
 
 309	retval = 0;
 
 
 
 
 
 
 
 
 
 
 
 310error_out:
 311	if (retval) {
 312		scsi_autopm_put_device(sdp->device);
 313sdp_put:
 314		scsi_device_put(sdp->device);
 315	}
 316sg_put:
 317	if (sdp)
 318		sg_put_dev(sdp);
 319	mutex_unlock(&sg_mutex);
 320	return retval;
 321}
 322
 323/* Following function was formerly called 'sg_close' */
 
 324static int
 325sg_release(struct inode *inode, struct file *filp)
 326{
 327	Sg_device *sdp;
 328	Sg_fd *sfp;
 329
 330	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 331		return -ENXIO;
 332	SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
 333
 334	sfp->closed = 1;
 335
 336	sdp->exclude = 0;
 337	wake_up_interruptible(&sdp->o_excl_wait);
 338
 
 339	scsi_autopm_put_device(sdp->device);
 340	kref_put(&sfp->f_ref, sg_remove_sfp);
 
 
 
 
 
 
 
 
 
 
 
 341	return 0;
 342}
 343
 344static ssize_t
 345sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 346{
 347	Sg_device *sdp;
 348	Sg_fd *sfp;
 349	Sg_request *srp;
 350	int req_pack_id = -1;
 351	sg_io_hdr_t *hp;
 352	struct sg_header *old_hdr = NULL;
 353	int retval = 0;
 354
 355	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 356		return -ENXIO;
 357	SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
 358				   sdp->disk->disk_name, (int) count));
 359
 360	if (!access_ok(VERIFY_WRITE, buf, count))
 361		return -EFAULT;
 362	if (sfp->force_packid && (count >= SZ_SG_HEADER)) {
 363		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 364		if (!old_hdr)
 365			return -ENOMEM;
 366		if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) {
 367			retval = -EFAULT;
 368			goto free_old_hdr;
 369		}
 370		if (old_hdr->reply_len < 0) {
 371			if (count >= SZ_SG_IO_HDR) {
 372				sg_io_hdr_t *new_hdr;
 373				new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL);
 374				if (!new_hdr) {
 375					retval = -ENOMEM;
 376					goto free_old_hdr;
 377				}
 378				retval =__copy_from_user
 379				    (new_hdr, buf, SZ_SG_IO_HDR);
 380				req_pack_id = new_hdr->pack_id;
 381				kfree(new_hdr);
 382				if (retval) {
 383					retval = -EFAULT;
 384					goto free_old_hdr;
 385				}
 386			}
 387		} else
 388			req_pack_id = old_hdr->pack_id;
 389	}
 390	srp = sg_get_rq_mark(sfp, req_pack_id);
 391	if (!srp) {		/* now wait on packet to arrive */
 392		if (sdp->detached) {
 393			retval = -ENODEV;
 394			goto free_old_hdr;
 395		}
 396		if (filp->f_flags & O_NONBLOCK) {
 397			retval = -EAGAIN;
 398			goto free_old_hdr;
 399		}
 400		while (1) {
 401			retval = 0; /* following macro beats race condition */
 402			__wait_event_interruptible(sfp->read_wait,
 403				(sdp->detached ||
 404				(srp = sg_get_rq_mark(sfp, req_pack_id))), 
 405				retval);
 406			if (sdp->detached) {
 407				retval = -ENODEV;
 408				goto free_old_hdr;
 409			}
 410			if (0 == retval)
 411				break;
 412
 413			/* -ERESTARTSYS as signal hit process */
 414			goto free_old_hdr;
 415		}
 416	}
 417	if (srp->header.interface_id != '\0') {
 418		retval = sg_new_read(sfp, buf, count, srp);
 419		goto free_old_hdr;
 420	}
 421
 422	hp = &srp->header;
 423	if (old_hdr == NULL) {
 424		old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL);
 425		if (! old_hdr) {
 426			retval = -ENOMEM;
 427			goto free_old_hdr;
 428		}
 429	}
 430	memset(old_hdr, 0, SZ_SG_HEADER);
 431	old_hdr->reply_len = (int) hp->timeout;
 432	old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */
 433	old_hdr->pack_id = hp->pack_id;
 434	old_hdr->twelve_byte =
 435	    ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;
 436	old_hdr->target_status = hp->masked_status;
 437	old_hdr->host_status = hp->host_status;
 438	old_hdr->driver_status = hp->driver_status;
 439	if ((CHECK_CONDITION & hp->masked_status) ||
 440	    (DRIVER_SENSE & hp->driver_status))
 441		memcpy(old_hdr->sense_buffer, srp->sense_b,
 442		       sizeof (old_hdr->sense_buffer));
 443	switch (hp->host_status) {
 444	/* This setup of 'result' is for backward compatibility and is best
 445	   ignored by the user who should use target, host + driver status */
 446	case DID_OK:
 447	case DID_PASSTHROUGH:
 448	case DID_SOFT_ERROR:
 449		old_hdr->result = 0;
 450		break;
 451	case DID_NO_CONNECT:
 452	case DID_BUS_BUSY:
 453	case DID_TIME_OUT:
 454		old_hdr->result = EBUSY;
 455		break;
 456	case DID_BAD_TARGET:
 457	case DID_ABORT:
 458	case DID_PARITY:
 459	case DID_RESET:
 460	case DID_BAD_INTR:
 461		old_hdr->result = EIO;
 462		break;
 463	case DID_ERROR:
 464		old_hdr->result = (srp->sense_b[0] == 0 && 
 465				  hp->masked_status == GOOD) ? 0 : EIO;
 466		break;
 467	default:
 468		old_hdr->result = EIO;
 469		break;
 470	}
 471
 472	/* Now copy the result back to the user buffer.  */
 473	if (count >= SZ_SG_HEADER) {
 474		if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {
 475			retval = -EFAULT;
 476			goto free_old_hdr;
 477		}
 478		buf += SZ_SG_HEADER;
 479		if (count > old_hdr->reply_len)
 480			count = old_hdr->reply_len;
 481		if (count > SZ_SG_HEADER) {
 482			if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {
 483				retval = -EFAULT;
 484				goto free_old_hdr;
 485			}
 486		}
 487	} else
 488		count = (old_hdr->result == 0) ? 0 : -EIO;
 489	sg_finish_rem_req(srp);
 490	retval = count;
 491free_old_hdr:
 492	kfree(old_hdr);
 493	return retval;
 494}
 495
 496static ssize_t
 497sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
 498{
 499	sg_io_hdr_t *hp = &srp->header;
 500	int err = 0;
 501	int len;
 502
 503	if (count < SZ_SG_IO_HDR) {
 504		err = -EINVAL;
 505		goto err_out;
 506	}
 507	hp->sb_len_wr = 0;
 508	if ((hp->mx_sb_len > 0) && hp->sbp) {
 509		if ((CHECK_CONDITION & hp->masked_status) ||
 510		    (DRIVER_SENSE & hp->driver_status)) {
 511			int sb_len = SCSI_SENSE_BUFFERSIZE;
 512			sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;
 513			len = 8 + (int) srp->sense_b[7];	/* Additional sense length field */
 514			len = (len > sb_len) ? sb_len : len;
 515			if (copy_to_user(hp->sbp, srp->sense_b, len)) {
 516				err = -EFAULT;
 517				goto err_out;
 518			}
 519			hp->sb_len_wr = len;
 520		}
 521	}
 522	if (hp->masked_status || hp->host_status || hp->driver_status)
 523		hp->info |= SG_INFO_CHECK;
 524	if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) {
 525		err = -EFAULT;
 526		goto err_out;
 527	}
 528err_out:
 529	err = sg_finish_rem_req(srp);
 530	return (0 == err) ? count : err;
 531}
 532
 533static ssize_t
 534sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 535{
 536	int mxsize, cmd_size, k;
 537	int input_size, blocking;
 538	unsigned char opcode;
 539	Sg_device *sdp;
 540	Sg_fd *sfp;
 541	Sg_request *srp;
 542	struct sg_header old_hdr;
 543	sg_io_hdr_t *hp;
 544	unsigned char cmnd[MAX_COMMAND_SIZE];
 
 
 
 545
 546	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 547		return -ENXIO;
 548	SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
 549				   sdp->disk->disk_name, (int) count));
 550	if (sdp->detached)
 551		return -ENODEV;
 552	if (!((filp->f_flags & O_NONBLOCK) ||
 553	      scsi_block_when_processing_errors(sdp->device)))
 554		return -ENXIO;
 555
 556	if (!access_ok(VERIFY_READ, buf, count))
 557		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 558	if (count < SZ_SG_HEADER)
 559		return -EIO;
 560	if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER))
 561		return -EFAULT;
 562	blocking = !(filp->f_flags & O_NONBLOCK);
 563	if (old_hdr.reply_len < 0)
 564		return sg_new_write(sfp, filp, buf, count,
 565				    blocking, 0, 0, NULL);
 566	if (count < (SZ_SG_HEADER + 6))
 567		return -EIO;	/* The minimum scsi command length is 6 bytes. */
 568
 569	if (!(srp = sg_add_request(sfp))) {
 570		SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n"));
 
 571		return -EDOM;
 572	}
 573	buf += SZ_SG_HEADER;
 574	__get_user(opcode, buf);
 575	if (sfp->next_cmd_len > 0) {
 576		if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
 577			SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
 578			sfp->next_cmd_len = 0;
 579			sg_remove_request(sfp, srp);
 580			return -EIO;
 581		}
 582		cmd_size = sfp->next_cmd_len;
 583		sfp->next_cmd_len = 0;	/* reset so only this write() effected */
 584	} else {
 585		cmd_size = COMMAND_SIZE(opcode);	/* based on SCSI command group */
 586		if ((opcode >= 0xc0) && old_hdr.twelve_byte)
 587			cmd_size = 12;
 588	}
 589	SCSI_LOG_TIMEOUT(4, printk(
 590		"sg_write:   scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));
 591/* Determine buffer size.  */
 592	input_size = count - cmd_size;
 593	mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;
 594	mxsize -= SZ_SG_HEADER;
 595	input_size -= SZ_SG_HEADER;
 596	if (input_size < 0) {
 597		sg_remove_request(sfp, srp);
 598		return -EIO;	/* User did not pass enough bytes for this command. */
 599	}
 600	hp = &srp->header;
 601	hp->interface_id = '\0';	/* indicator of old interface tunnelled */
 602	hp->cmd_len = (unsigned char) cmd_size;
 603	hp->iovec_count = 0;
 604	hp->mx_sb_len = 0;
 605	if (input_size > 0)
 606		hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?
 607		    SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;
 608	else
 609		hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;
 610	hp->dxfer_len = mxsize;
 611	if (hp->dxfer_direction == SG_DXFER_TO_DEV)
 
 612		hp->dxferp = (char __user *)buf + cmd_size;
 613	else
 614		hp->dxferp = NULL;
 615	hp->sbp = NULL;
 616	hp->timeout = old_hdr.reply_len;	/* structure abuse ... */
 617	hp->flags = input_size;	/* structure abuse ... */
 618	hp->pack_id = old_hdr.pack_id;
 619	hp->usr_ptr = NULL;
 620	if (__copy_from_user(cmnd, buf, cmd_size))
 621		return -EFAULT;
 622	/*
 623	 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,
 624	 * but is is possible that the app intended SG_DXFER_TO_DEV, because there
 625	 * is a non-zero input_size, so emit a warning.
 626	 */
 627	if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {
 628		static char cmd[TASK_COMM_LEN];
 629		if (strcmp(current->comm, cmd) && printk_ratelimit()) {
 630			printk(KERN_WARNING
 631			       "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--"
 632			       "guessing data in;\n   "
 633			       "program %s not setting count and/or reply_len properly\n",
 634			       old_hdr.reply_len - (int)SZ_SG_HEADER,
 635			       input_size, (unsigned int) cmnd[0],
 636			       current->comm);
 
 637			strcpy(cmd, current->comm);
 638		}
 639	}
 640	k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);
 641	return (k < 0) ? k : count;
 642}
 643
 644static ssize_t
 645sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
 646		 size_t count, int blocking, int read_only, int sg_io_owned,
 647		 Sg_request **o_srp)
 648{
 649	int k;
 650	Sg_request *srp;
 651	sg_io_hdr_t *hp;
 652	unsigned char cmnd[MAX_COMMAND_SIZE];
 653	int timeout;
 654	unsigned long ul_timeout;
 655
 656	if (count < SZ_SG_IO_HDR)
 657		return -EINVAL;
 658	if (!access_ok(VERIFY_READ, buf, count))
 659		return -EFAULT; /* protects following copy_from_user()s + get_user()s */
 660
 661	sfp->cmd_q = 1;	/* when sg_io_hdr seen, set command queuing on */
 662	if (!(srp = sg_add_request(sfp))) {
 663		SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n"));
 
 664		return -EDOM;
 665	}
 666	srp->sg_io_owned = sg_io_owned;
 667	hp = &srp->header;
 668	if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) {
 669		sg_remove_request(sfp, srp);
 670		return -EFAULT;
 671	}
 672	if (hp->interface_id != 'S') {
 673		sg_remove_request(sfp, srp);
 674		return -ENOSYS;
 675	}
 676	if (hp->flags & SG_FLAG_MMAP_IO) {
 677		if (hp->dxfer_len > sfp->reserve.bufflen) {
 678			sg_remove_request(sfp, srp);
 679			return -ENOMEM;	/* MMAP_IO size must fit in reserve buffer */
 680		}
 681		if (hp->flags & SG_FLAG_DIRECT_IO) {
 682			sg_remove_request(sfp, srp);
 683			return -EINVAL;	/* either MMAP_IO or DIRECT_IO (not both) */
 684		}
 685		if (sg_res_in_use(sfp)) {
 686			sg_remove_request(sfp, srp);
 687			return -EBUSY;	/* reserve buffer already being used */
 688		}
 689	}
 690	ul_timeout = msecs_to_jiffies(srp->header.timeout);
 691	timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;
 692	if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {
 693		sg_remove_request(sfp, srp);
 694		return -EMSGSIZE;
 695	}
 696	if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) {
 697		sg_remove_request(sfp, srp);
 698		return -EFAULT;	/* protects following copy_from_user()s + get_user()s */
 699	}
 700	if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {
 701		sg_remove_request(sfp, srp);
 702		return -EFAULT;
 703	}
 704	if (read_only && sg_allow_access(file, cmnd)) {
 705		sg_remove_request(sfp, srp);
 706		return -EPERM;
 707	}
 708	k = sg_common_write(sfp, srp, cmnd, timeout, blocking);
 709	if (k < 0)
 710		return k;
 711	if (o_srp)
 712		*o_srp = srp;
 713	return count;
 714}
 715
 716static int
 717sg_common_write(Sg_fd * sfp, Sg_request * srp,
 718		unsigned char *cmnd, int timeout, int blocking)
 719{
 720	int k, data_dir;
 721	Sg_device *sdp = sfp->parentdp;
 722	sg_io_hdr_t *hp = &srp->header;
 723
 724	srp->data.cmd_opcode = cmnd[0];	/* hold opcode of command */
 725	hp->status = 0;
 726	hp->masked_status = 0;
 727	hp->msg_status = 0;
 728	hp->info = 0;
 729	hp->host_status = 0;
 730	hp->driver_status = 0;
 731	hp->resid = 0;
 732	SCSI_LOG_TIMEOUT(4, printk("sg_common_write:  scsi opcode=0x%02x, cmd_size=%d\n",
 733			  (int) cmnd[0], (int) hp->cmd_len));
 
 734
 735	k = sg_start_req(srp, cmnd);
 736	if (k) {
 737		SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k));
 
 738		sg_finish_rem_req(srp);
 739		return k;	/* probably out of space --> ENOMEM */
 740	}
 741	if (sdp->detached) {
 742		if (srp->bio)
 
 
 
 743			blk_end_request_all(srp->rq, -EIO);
 
 
 
 744		sg_finish_rem_req(srp);
 745		return -ENODEV;
 746	}
 747
 748	switch (hp->dxfer_direction) {
 749	case SG_DXFER_TO_FROM_DEV:
 750	case SG_DXFER_FROM_DEV:
 751		data_dir = DMA_FROM_DEVICE;
 752		break;
 753	case SG_DXFER_TO_DEV:
 754		data_dir = DMA_TO_DEVICE;
 755		break;
 756	case SG_DXFER_UNKNOWN:
 757		data_dir = DMA_BIDIRECTIONAL;
 758		break;
 759	default:
 760		data_dir = DMA_NONE;
 761		break;
 762	}
 763	hp->duration = jiffies_to_msecs(jiffies);
 
 
 
 
 
 764
 765	srp->rq->timeout = timeout;
 766	kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */
 767	blk_execute_rq_nowait(sdp->device->request_queue, sdp->disk,
 768			      srp->rq, 1, sg_rq_end_io);
 769	return 0;
 770}
 771
 772static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 773sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
 774{
 775	void __user *p = (void __user *)arg;
 776	int __user *ip = p;
 777	int result, val, read_only;
 778	Sg_device *sdp;
 779	Sg_fd *sfp;
 780	Sg_request *srp;
 781	unsigned long iflags;
 782
 783	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
 784		return -ENXIO;
 785
 786	SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
 787				   sdp->disk->disk_name, (int) cmd_in));
 788	read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
 789
 790	switch (cmd_in) {
 791	case SG_IO:
 792		{
 793			int blocking = 1;	/* ignore O_NONBLOCK flag */
 794
 795			if (sdp->detached)
 796				return -ENODEV;
 797			if (!scsi_block_when_processing_errors(sdp->device))
 798				return -ENXIO;
 799			if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR))
 800				return -EFAULT;
 801			result =
 802			    sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,
 803					 blocking, read_only, 1, &srp);
 804			if (result < 0)
 805				return result;
 806			while (1) {
 807				result = 0;	/* following macro to beat race condition */
 808				__wait_event_interruptible(sfp->read_wait,
 809					(srp->done || sdp->detached),
 810					result);
 811				if (sdp->detached)
 812					return -ENODEV;
 813				write_lock_irq(&sfp->rq_list_lock);
 814				if (srp->done) {
 815					srp->done = 2;
 816					write_unlock_irq(&sfp->rq_list_lock);
 817					break;
 818				}
 819				srp->orphan = 1;
 820				write_unlock_irq(&sfp->rq_list_lock);
 821				return result;	/* -ERESTARTSYS because signal hit process */
 822			}
 823			result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);
 824			return (result < 0) ? result : 0;
 825		}
 
 
 
 826	case SG_SET_TIMEOUT:
 827		result = get_user(val, ip);
 828		if (result)
 829			return result;
 830		if (val < 0)
 831			return -EIO;
 832		if (val >= MULDIV (INT_MAX, USER_HZ, HZ))
 833		    val = MULDIV (INT_MAX, USER_HZ, HZ);
 
 834		sfp->timeout_user = val;
 835		sfp->timeout = MULDIV (val, HZ, USER_HZ);
 836
 837		return 0;
 838	case SG_GET_TIMEOUT:	/* N.B. User receives timeout as return value */
 839				/* strange ..., for backward compatibility */
 840		return sfp->timeout_user;
 841	case SG_SET_FORCE_LOW_DMA:
 842		result = get_user(val, ip);
 843		if (result)
 844			return result;
 845		if (val) {
 846			sfp->low_dma = 1;
 847			if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
 848				val = (int) sfp->reserve.bufflen;
 849				sg_remove_scat(&sfp->reserve);
 850				sg_build_reserve(sfp, val);
 851			}
 852		} else {
 853			if (sdp->detached)
 854				return -ENODEV;
 855			sfp->low_dma = sdp->device->host->unchecked_isa_dma;
 856		}
 857		return 0;
 858	case SG_GET_LOW_DMA:
 859		return put_user((int) sfp->low_dma, ip);
 860	case SG_GET_SCSI_ID:
 861		if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t)))
 862			return -EFAULT;
 863		else {
 864			sg_scsi_id_t __user *sg_idp = p;
 865
 866			if (sdp->detached)
 867				return -ENODEV;
 868			__put_user((int) sdp->device->host->host_no,
 869				   &sg_idp->host_no);
 870			__put_user((int) sdp->device->channel,
 871				   &sg_idp->channel);
 872			__put_user((int) sdp->device->id, &sg_idp->scsi_id);
 873			__put_user((int) sdp->device->lun, &sg_idp->lun);
 874			__put_user((int) sdp->device->type, &sg_idp->scsi_type);
 875			__put_user((short) sdp->device->host->cmd_per_lun,
 876				   &sg_idp->h_cmd_per_lun);
 877			__put_user((short) sdp->device->queue_depth,
 878				   &sg_idp->d_queue_depth);
 879			__put_user(0, &sg_idp->unused[0]);
 880			__put_user(0, &sg_idp->unused[1]);
 881			return 0;
 882		}
 883	case SG_SET_FORCE_PACK_ID:
 884		result = get_user(val, ip);
 885		if (result)
 886			return result;
 887		sfp->force_packid = val ? 1 : 0;
 888		return 0;
 889	case SG_GET_PACK_ID:
 890		if (!access_ok(VERIFY_WRITE, ip, sizeof (int)))
 891			return -EFAULT;
 892		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 893		for (srp = sfp->headrp; srp; srp = srp->nextrp) {
 894			if ((1 == srp->done) && (!srp->sg_io_owned)) {
 895				read_unlock_irqrestore(&sfp->rq_list_lock,
 896						       iflags);
 897				__put_user(srp->header.pack_id, ip);
 898				return 0;
 899			}
 900		}
 901		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 902		__put_user(-1, ip);
 903		return 0;
 904	case SG_GET_NUM_WAITING:
 905		read_lock_irqsave(&sfp->rq_list_lock, iflags);
 906		for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) {
 907			if ((1 == srp->done) && (!srp->sg_io_owned))
 908				++val;
 909		}
 910		read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
 911		return put_user(val, ip);
 912	case SG_GET_SG_TABLESIZE:
 913		return put_user(sdp->sg_tablesize, ip);
 914	case SG_SET_RESERVED_SIZE:
 915		result = get_user(val, ip);
 916		if (result)
 917			return result;
 918                if (val < 0)
 919                        return -EINVAL;
 920		val = min_t(int, val,
 921			    queue_max_sectors(sdp->device->request_queue) * 512);
 922		if (val != sfp->reserve.bufflen) {
 923			if (sg_res_in_use(sfp) || sfp->mmap_called)
 924				return -EBUSY;
 925			sg_remove_scat(&sfp->reserve);
 926			sg_build_reserve(sfp, val);
 927		}
 928		return 0;
 929	case SG_GET_RESERVED_SIZE:
 930		val = min_t(int, sfp->reserve.bufflen,
 931			    queue_max_sectors(sdp->device->request_queue) * 512);
 932		return put_user(val, ip);
 933	case SG_SET_COMMAND_Q:
 934		result = get_user(val, ip);
 935		if (result)
 936			return result;
 937		sfp->cmd_q = val ? 1 : 0;
 938		return 0;
 939	case SG_GET_COMMAND_Q:
 940		return put_user((int) sfp->cmd_q, ip);
 941	case SG_SET_KEEP_ORPHAN:
 942		result = get_user(val, ip);
 943		if (result)
 944			return result;
 945		sfp->keep_orphan = val;
 946		return 0;
 947	case SG_GET_KEEP_ORPHAN:
 948		return put_user((int) sfp->keep_orphan, ip);
 949	case SG_NEXT_CMD_LEN:
 950		result = get_user(val, ip);
 951		if (result)
 952			return result;
 
 
 953		sfp->next_cmd_len = (val > 0) ? val : 0;
 954		return 0;
 955	case SG_GET_VERSION_NUM:
 956		return put_user(sg_version_num, ip);
 957	case SG_GET_ACCESS_COUNT:
 958		/* faked - we don't have a real access count anymore */
 959		val = (sdp->device ? 1 : 0);
 960		return put_user(val, ip);
 961	case SG_GET_REQUEST_TABLE:
 962		if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE))
 963			return -EFAULT;
 964		else {
 965			sg_req_info_t *rinfo;
 966			unsigned int ms;
 967
 968			rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE,
 969								GFP_KERNEL);
 970			if (!rinfo)
 971				return -ENOMEM;
 972			read_lock_irqsave(&sfp->rq_list_lock, iflags);
 973			for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE;
 974			     ++val, srp = srp ? srp->nextrp : srp) {
 975				memset(&rinfo[val], 0, SZ_SG_REQ_INFO);
 976				if (srp) {
 977					rinfo[val].req_state = srp->done + 1;
 978					rinfo[val].problem =
 979					    srp->header.masked_status & 
 980					    srp->header.host_status & 
 981					    srp->header.driver_status;
 982					if (srp->done)
 983						rinfo[val].duration =
 984							srp->header.duration;
 985					else {
 986						ms = jiffies_to_msecs(jiffies);
 987						rinfo[val].duration =
 988						    (ms > srp->header.duration) ?
 989						    (ms - srp->header.duration) : 0;
 990					}
 991					rinfo[val].orphan = srp->orphan;
 992					rinfo[val].sg_io_owned =
 993							srp->sg_io_owned;
 994					rinfo[val].pack_id =
 995							srp->header.pack_id;
 996					rinfo[val].usr_ptr =
 997							srp->header.usr_ptr;
 998				}
 999			}
1000			read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1001			result = __copy_to_user(p, rinfo, 
1002						SZ_SG_REQ_INFO * SG_MAX_QUEUE);
1003			result = result ? -EFAULT : 0;
1004			kfree(rinfo);
1005			return result;
1006		}
1007	case SG_EMULATED_HOST:
1008		if (sdp->detached)
1009			return -ENODEV;
1010		return put_user(sdp->device->host->hostt->emulated, ip);
1011	case SG_SCSI_RESET:
1012		if (sdp->detached)
1013			return -ENODEV;
1014		if (filp->f_flags & O_NONBLOCK) {
1015			if (scsi_host_in_recovery(sdp->device->host))
1016				return -EBUSY;
1017		} else if (!scsi_block_when_processing_errors(sdp->device))
1018			return -EBUSY;
1019		result = get_user(val, ip);
1020		if (result)
1021			return result;
1022		if (SG_SCSI_RESET_NOTHING == val)
1023			return 0;
1024		switch (val) {
1025		case SG_SCSI_RESET_DEVICE:
1026			val = SCSI_TRY_RESET_DEVICE;
1027			break;
1028		case SG_SCSI_RESET_TARGET:
1029			val = SCSI_TRY_RESET_TARGET;
1030			break;
1031		case SG_SCSI_RESET_BUS:
1032			val = SCSI_TRY_RESET_BUS;
1033			break;
1034		case SG_SCSI_RESET_HOST:
1035			val = SCSI_TRY_RESET_HOST;
1036			break;
1037		default:
1038			return -EINVAL;
1039		}
1040		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1041			return -EACCES;
1042		return (scsi_reset_provider(sdp->device, val) ==
1043			SUCCESS) ? 0 : -EIO;
1044	case SCSI_IOCTL_SEND_COMMAND:
1045		if (sdp->detached)
1046			return -ENODEV;
1047		if (read_only) {
1048			unsigned char opcode = WRITE_6;
1049			Scsi_Ioctl_Command __user *siocp = p;
1050
1051			if (copy_from_user(&opcode, siocp->data, 1))
1052				return -EFAULT;
1053			if (sg_allow_access(filp, &opcode))
1054				return -EPERM;
1055		}
1056		return sg_scsi_ioctl(sdp->device->request_queue, NULL, filp->f_mode, p);
1057	case SG_SET_DEBUG:
1058		result = get_user(val, ip);
1059		if (result)
1060			return result;
1061		sdp->sgdebug = (char) val;
1062		return 0;
1063	case SCSI_IOCTL_GET_IDLUN:
1064	case SCSI_IOCTL_GET_BUS_NUMBER:
1065	case SCSI_IOCTL_PROBE_HOST:
1066	case SG_GET_TRANSFORM:
1067		if (sdp->detached)
1068			return -ENODEV;
1069		return scsi_ioctl(sdp->device, cmd_in, p);
1070	case BLKSECTGET:
1071		return put_user(queue_max_sectors(sdp->device->request_queue) * 512,
1072				ip);
1073	case BLKTRACESETUP:
1074		return blk_trace_setup(sdp->device->request_queue,
1075				       sdp->disk->disk_name,
1076				       MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
1077				       NULL,
1078				       (char *)arg);
1079	case BLKTRACESTART:
1080		return blk_trace_startstop(sdp->device->request_queue, 1);
1081	case BLKTRACESTOP:
1082		return blk_trace_startstop(sdp->device->request_queue, 0);
1083	case BLKTRACETEARDOWN:
1084		return blk_trace_remove(sdp->device->request_queue);
 
 
 
 
 
 
 
 
1085	default:
1086		if (read_only)
1087			return -EPERM;	/* don't know so take safe approach */
1088		return scsi_ioctl(sdp->device, cmd_in, p);
1089	}
1090}
1091
1092static long
1093sg_unlocked_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1094{
1095	int ret;
1096
1097	mutex_lock(&sg_mutex);
1098	ret = sg_ioctl(filp, cmd_in, arg);
1099	mutex_unlock(&sg_mutex);
1100
1101	return ret;
 
 
 
 
1102}
1103
1104#ifdef CONFIG_COMPAT
1105static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)
1106{
1107	Sg_device *sdp;
1108	Sg_fd *sfp;
1109	struct scsi_device *sdev;
1110
1111	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1112		return -ENXIO;
1113
1114	sdev = sdp->device;
1115	if (sdev->host->hostt->compat_ioctl) { 
1116		int ret;
1117
1118		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
1119
1120		return ret;
1121	}
1122	
1123	return -ENOIOCTLCMD;
1124}
1125#endif
1126
1127static unsigned int
1128sg_poll(struct file *filp, poll_table * wait)
1129{
1130	unsigned int res = 0;
1131	Sg_device *sdp;
1132	Sg_fd *sfp;
1133	Sg_request *srp;
1134	int count = 0;
1135	unsigned long iflags;
1136
1137	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))
1138	    || sfp->closed)
 
 
 
1139		return POLLERR;
1140	poll_wait(filp, &sfp->read_wait, wait);
1141	read_lock_irqsave(&sfp->rq_list_lock, iflags);
1142	for (srp = sfp->headrp; srp; srp = srp->nextrp) {
1143		/* if any read waiting, flag it */
1144		if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))
1145			res = POLLIN | POLLRDNORM;
1146		++count;
1147	}
1148	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1149
1150	if (sdp->detached)
1151		res |= POLLHUP;
1152	else if (!sfp->cmd_q) {
1153		if (0 == count)
1154			res |= POLLOUT | POLLWRNORM;
1155	} else if (count < SG_MAX_QUEUE)
1156		res |= POLLOUT | POLLWRNORM;
1157	SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
1158				   sdp->disk->disk_name, (int) res));
1159	return res;
1160}
1161
1162static int
1163sg_fasync(int fd, struct file *filp, int mode)
1164{
1165	Sg_device *sdp;
1166	Sg_fd *sfp;
1167
1168	if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
1169		return -ENXIO;
1170	SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
1171				   sdp->disk->disk_name, mode));
1172
1173	return fasync_helper(fd, filp, mode, &sfp->async_qp);
1174}
1175
1176static int
1177sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
1178{
1179	Sg_fd *sfp;
1180	unsigned long offset, len, sa;
1181	Sg_scatter_hold *rsv_schp;
1182	int k, length;
1183
1184	if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))
1185		return VM_FAULT_SIGBUS;
1186	rsv_schp = &sfp->reserve;
1187	offset = vmf->pgoff << PAGE_SHIFT;
1188	if (offset >= rsv_schp->bufflen)
1189		return VM_FAULT_SIGBUS;
1190	SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n",
1191				   offset, rsv_schp->k_use_sg));
 
1192	sa = vma->vm_start;
1193	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1194	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1195		len = vma->vm_end - sa;
1196		len = (len < length) ? len : length;
1197		if (offset < len) {
1198			struct page *page = nth_page(rsv_schp->pages[k],
1199						     offset >> PAGE_SHIFT);
1200			get_page(page);	/* increment page count */
1201			vmf->page = page;
1202			return 0; /* success */
1203		}
1204		sa += len;
1205		offset -= len;
1206	}
1207
1208	return VM_FAULT_SIGBUS;
1209}
1210
1211static const struct vm_operations_struct sg_mmap_vm_ops = {
1212	.fault = sg_vma_fault,
1213};
1214
1215static int
1216sg_mmap(struct file *filp, struct vm_area_struct *vma)
1217{
1218	Sg_fd *sfp;
1219	unsigned long req_sz, len, sa;
1220	Sg_scatter_hold *rsv_schp;
1221	int k, length;
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	length = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1236	for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {
1237		len = vma->vm_end - sa;
1238		len = (len < length) ? len : length;
1239		sa += len;
1240	}
1241
1242	sfp->mmap_called = 1;
1243	vma->vm_flags |= VM_RESERVED;
1244	vma->vm_private_data = sfp;
1245	vma->vm_ops = &sg_mmap_vm_ops;
1246	return 0;
1247}
1248
1249static void sg_rq_end_io_usercontext(struct work_struct *work)
 
1250{
1251	struct sg_request *srp = container_of(work, struct sg_request, ew.work);
1252	struct sg_fd *sfp = srp->parentfp;
1253
1254	sg_finish_rem_req(srp);
1255	kref_put(&sfp->f_ref, sg_remove_sfp);
1256}
1257
1258/*
1259 * This function is a "bottom half" handler that is called by the mid
1260 * level when a command is completed (or has failed).
1261 */
1262static void sg_rq_end_io(struct request *rq, int uptodate)
 
1263{
1264	struct sg_request *srp = rq->end_io_data;
1265	Sg_device *sdp;
1266	Sg_fd *sfp;
1267	unsigned long iflags;
1268	unsigned int ms;
1269	char *sense;
1270	int result, resid, done = 1;
1271
1272	if (WARN_ON(srp->done != 0))
1273		return;
1274
1275	sfp = srp->parentfp;
1276	if (WARN_ON(sfp == NULL))
1277		return;
1278
1279	sdp = sfp->parentdp;
1280	if (unlikely(sdp->detached))
1281		printk(KERN_INFO "sg_rq_end_io: device detached\n");
1282
1283	sense = rq->sense;
1284	result = rq->errors;
1285	resid = rq->resid_len;
1286
1287	SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
1288		sdp->disk->disk_name, srp->header.pack_id, result));
 
1289	srp->header.resid = resid;
1290	ms = jiffies_to_msecs(jiffies);
1291	srp->header.duration = (ms > srp->header.duration) ?
1292				(ms - srp->header.duration) : 0;
1293	if (0 != result) {
1294		struct scsi_sense_hdr sshdr;
1295
1296		srp->header.status = 0xff & result;
1297		srp->header.masked_status = status_byte(result);
1298		srp->header.msg_status = msg_byte(result);
1299		srp->header.host_status = host_byte(result);
1300		srp->header.driver_status = driver_byte(result);
1301		if ((sdp->sgdebug > 0) &&
1302		    ((CHECK_CONDITION == srp->header.masked_status) ||
1303		     (COMMAND_TERMINATED == srp->header.masked_status)))
1304			__scsi_print_sense("sg_cmd_done", sense,
1305					   SCSI_SENSE_BUFFERSIZE);
1306
1307		/* Following if statement is a patch supplied by Eric Youngdale */
1308		if (driver_byte(result) != 0
1309		    && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)
1310		    && !scsi_sense_is_deferred(&sshdr)
1311		    && sshdr.sense_key == UNIT_ATTENTION
1312		    && sdp->device->removable) {
1313			/* Detected possible disc change. Set the bit - this */
1314			/* may be used if there are filesystems using this device */
1315			sdp->device->changed = 1;
1316		}
1317	}
1318	/* Rely on write phase to clean out srp status values, so no "else" */
1319
 
 
 
 
 
 
 
 
 
 
 
1320	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1321	if (unlikely(srp->orphan)) {
1322		if (sfp->keep_orphan)
1323			srp->sg_io_owned = 0;
1324		else
1325			done = 0;
1326	}
1327	srp->done = done;
1328	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1329
1330	if (likely(done)) {
1331		/* Now wake up any sg_read() that is waiting for this
1332		 * packet.
1333		 */
1334		wake_up_interruptible(&sfp->read_wait);
1335		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);
1336		kref_put(&sfp->f_ref, sg_remove_sfp);
1337	} else {
1338		INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);
1339		schedule_work(&srp->ew.work);
1340	}
1341}
1342
1343static const struct file_operations sg_fops = {
1344	.owner = THIS_MODULE,
1345	.read = sg_read,
1346	.write = sg_write,
1347	.poll = sg_poll,
1348	.unlocked_ioctl = sg_unlocked_ioctl,
1349#ifdef CONFIG_COMPAT
1350	.compat_ioctl = sg_compat_ioctl,
1351#endif
1352	.open = sg_open,
1353	.mmap = sg_mmap,
1354	.release = sg_release,
1355	.fasync = sg_fasync,
1356	.llseek = no_llseek,
1357};
1358
1359static struct class *sg_sysfs_class;
1360
1361static int sg_sysfs_valid = 0;
1362
1363static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
 
1364{
1365	struct request_queue *q = scsidp->request_queue;
1366	Sg_device *sdp;
1367	unsigned long iflags;
1368	int error;
1369	u32 k;
1370
1371	sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
1372	if (!sdp) {
1373		printk(KERN_WARNING "kmalloc Sg_device failure\n");
 
1374		return ERR_PTR(-ENOMEM);
1375	}
1376
1377	if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
1378		printk(KERN_WARNING "idr expansion Sg_device failure\n");
1379		error = -ENOMEM;
1380		goto out;
1381	}
1382
1383	write_lock_irqsave(&sg_index_lock, iflags);
1384
1385	error = idr_get_new(&sg_index_idr, sdp, &k);
1386	if (error) {
1387		write_unlock_irqrestore(&sg_index_lock, iflags);
1388		printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
1389		       error);
1390		goto out;
 
 
 
 
 
 
 
1391	}
 
1392
1393	if (unlikely(k >= SG_MAX_DEVS))
1394		goto overflow;
1395
1396	SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
1397	sprintf(disk->disk_name, "sg%d", k);
1398	disk->first_minor = k;
1399	sdp->disk = disk;
1400	sdp->device = scsidp;
 
1401	INIT_LIST_HEAD(&sdp->sfds);
1402	init_waitqueue_head(&sdp->o_excl_wait);
 
 
1403	sdp->sg_tablesize = queue_max_segments(q);
1404	sdp->index = k;
1405	kref_init(&sdp->d_ref);
 
1406
 
1407	write_unlock_irqrestore(&sg_index_lock, iflags);
 
1408
1409	error = 0;
1410 out:
1411	if (error) {
1412		kfree(sdp);
1413		return ERR_PTR(error);
1414	}
1415	return sdp;
1416
1417 overflow:
1418	idr_remove(&sg_index_idr, k);
1419	write_unlock_irqrestore(&sg_index_lock, iflags);
1420	sdev_printk(KERN_WARNING, scsidp,
1421		    "Unable to attach sg device type=%d, minor "
1422		    "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
1423	error = -ENODEV;
1424	goto out;
1425}
1426
1427static int
1428sg_add(struct device *cl_dev, struct class_interface *cl_intf)
1429{
1430	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1431	struct gendisk *disk;
1432	Sg_device *sdp = NULL;
1433	struct cdev * cdev = NULL;
1434	int error;
1435	unsigned long iflags;
1436
1437	disk = alloc_disk(1);
1438	if (!disk) {
1439		printk(KERN_WARNING "alloc_disk failed\n");
1440		return -ENOMEM;
1441	}
1442	disk->major = SCSI_GENERIC_MAJOR;
1443
1444	error = -ENOMEM;
1445	cdev = cdev_alloc();
1446	if (!cdev) {
1447		printk(KERN_WARNING "cdev_alloc failed\n");
1448		goto out;
1449	}
1450	cdev->owner = THIS_MODULE;
1451	cdev->ops = &sg_fops;
1452
1453	sdp = sg_alloc(disk, scsidp);
1454	if (IS_ERR(sdp)) {
1455		printk(KERN_WARNING "sg_alloc failed\n");
1456		error = PTR_ERR(sdp);
1457		goto out;
1458	}
1459
1460	error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
1461	if (error)
1462		goto cdev_add_err;
1463
1464	sdp->cdev = cdev;
1465	if (sg_sysfs_valid) {
1466		struct device *sg_class_member;
1467
1468		sg_class_member = device_create(sg_sysfs_class, cl_dev->parent,
1469						MKDEV(SCSI_GENERIC_MAJOR,
1470						      sdp->index),
1471						sdp, "%s", disk->disk_name);
1472		if (IS_ERR(sg_class_member)) {
1473			printk(KERN_ERR "sg_add: "
1474			       "device_create failed\n");
1475			error = PTR_ERR(sg_class_member);
1476			goto cdev_add_err;
1477		}
1478		error = sysfs_create_link(&scsidp->sdev_gendev.kobj,
1479					  &sg_class_member->kobj, "generic");
1480		if (error)
1481			printk(KERN_ERR "sg_add: unable to make symlink "
1482					"'generic' back to sg%d\n", sdp->index);
1483	} else
1484		printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
1485
1486	sdev_printk(KERN_NOTICE, scsidp,
1487		    "Attached scsi generic sg%d type %d\n", sdp->index,
1488		    scsidp->type);
1489
1490	dev_set_drvdata(cl_dev, sdp);
1491
1492	return 0;
1493
1494cdev_add_err:
1495	write_lock_irqsave(&sg_index_lock, iflags);
1496	idr_remove(&sg_index_idr, sdp->index);
1497	write_unlock_irqrestore(&sg_index_lock, iflags);
1498	kfree(sdp);
1499
1500out:
1501	put_disk(disk);
1502	if (cdev)
1503		cdev_del(cdev);
1504	return error;
1505}
1506
1507static void sg_device_destroy(struct kref *kref)
 
1508{
1509	struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);
1510	unsigned long flags;
1511
1512	/* CAUTION!  Note that the device can still be found via idr_find()
1513	 * even though the refcount is 0.  Therefore, do idr_remove() BEFORE
1514	 * any other cleanup.
1515	 */
1516
1517	write_lock_irqsave(&sg_index_lock, flags);
1518	idr_remove(&sg_index_idr, sdp->index);
1519	write_unlock_irqrestore(&sg_index_lock, flags);
1520
1521	SCSI_LOG_TIMEOUT(3,
1522		printk("sg_device_destroy: %s\n",
1523			sdp->disk->disk_name));
1524
1525	put_disk(sdp->disk);
1526	kfree(sdp);
1527}
1528
1529static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf)
 
1530{
1531	struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);
1532	Sg_device *sdp = dev_get_drvdata(cl_dev);
1533	unsigned long iflags;
1534	Sg_fd *sfp;
 
1535
1536	if (!sdp || sdp->detached)
1537		return;
 
 
 
 
1538
1539	SCSI_LOG_TIMEOUT(3, printk("sg_remove: %s\n", sdp->disk->disk_name));
 
1540
1541	/* Need a write lock to set sdp->detached. */
1542	write_lock_irqsave(&sg_index_lock, iflags);
1543	sdp->detached = 1;
1544	list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {
1545		wake_up_interruptible(&sfp->read_wait);
1546		kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);
1547	}
1548	write_unlock_irqrestore(&sg_index_lock, iflags);
 
1549
1550	sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
1551	device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
1552	cdev_del(sdp->cdev);
1553	sdp->cdev = NULL;
1554
1555	sg_put_dev(sdp);
1556}
1557
1558module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);
1559module_param_named(def_reserved_size, def_reserved_size, int,
1560		   S_IRUGO | S_IWUSR);
1561module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);
1562
1563MODULE_AUTHOR("Douglas Gilbert");
1564MODULE_DESCRIPTION("SCSI generic (sg) driver");
1565MODULE_LICENSE("GPL");
1566MODULE_VERSION(SG_VERSION_STR);
1567MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);
1568
1569MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "
1570                "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");
1571MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");
1572MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");
1573
1574static int __init
1575init_sg(void)
1576{
1577	int rc;
1578
1579	if (scatter_elem_sz < PAGE_SIZE) {
1580		scatter_elem_sz = PAGE_SIZE;
1581		scatter_elem_sz_prev = scatter_elem_sz;
1582	}
1583	if (def_reserved_size >= 0)
1584		sg_big_buff = def_reserved_size;
1585	else
1586		def_reserved_size = sg_big_buff;
1587
1588	rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 
1589				    SG_MAX_DEVS, "sg");
1590	if (rc)
1591		return rc;
1592        sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic");
1593        if ( IS_ERR(sg_sysfs_class) ) {
1594		rc = PTR_ERR(sg_sysfs_class);
1595		goto err_out;
1596        }
1597	sg_sysfs_valid = 1;
1598	rc = scsi_register_interface(&sg_interface);
1599	if (0 == rc) {
1600#ifdef CONFIG_SCSI_PROC_FS
1601		sg_proc_init();
1602#endif				/* CONFIG_SCSI_PROC_FS */
1603		return 0;
1604	}
1605	class_destroy(sg_sysfs_class);
1606err_out:
1607	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);
1608	return rc;
1609}
1610
1611static void __exit
1612exit_sg(void)
1613{
1614#ifdef CONFIG_SCSI_PROC_FS
1615	sg_proc_cleanup();
1616#endif				/* CONFIG_SCSI_PROC_FS */
1617	scsi_unregister_interface(&sg_interface);
1618	class_destroy(sg_sysfs_class);
1619	sg_sysfs_valid = 0;
1620	unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
1621				 SG_MAX_DEVS);
1622	idr_destroy(&sg_index_idr);
1623}
1624
1625static int sg_start_req(Sg_request *srp, unsigned char *cmd)
 
1626{
1627	int res;
1628	struct request *rq;
1629	Sg_fd *sfp = srp->parentfp;
1630	sg_io_hdr_t *hp = &srp->header;
1631	int dxfer_len = (int) hp->dxfer_len;
1632	int dxfer_dir = hp->dxfer_direction;
1633	unsigned int iov_count = hp->iovec_count;
1634	Sg_scatter_hold *req_schp = &srp->data;
1635	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1636	struct request_queue *q = sfp->parentdp->device->request_queue;
1637	struct rq_map_data *md, map_data;
1638	int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ;
 
 
 
 
 
 
 
 
 
 
 
1639
1640	SCSI_LOG_TIMEOUT(4, printk(KERN_INFO "sg_start_req: dxfer_len=%d\n",
1641				   dxfer_len));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1642
1643	rq = blk_get_request(q, rw, GFP_ATOMIC);
1644	if (!rq)
1645		return -ENOMEM;
1646
 
 
1647	memcpy(rq->cmd, cmd, hp->cmd_len);
1648
1649	rq->cmd_len = hp->cmd_len;
1650	rq->cmd_type = REQ_TYPE_BLOCK_PC;
1651
1652	srp->rq = rq;
1653	rq->end_io_data = srp;
1654	rq->sense = srp->sense_b;
1655	rq->retries = SG_DEFAULT_RETRIES;
1656
1657	if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))
1658		return 0;
1659
1660	if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&
1661	    dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&
1662	    !sfp->parentdp->device->host->unchecked_isa_dma &&
1663	    blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))
1664		md = NULL;
1665	else
1666		md = &map_data;
1667
1668	if (md) {
1669		if (!sg_res_in_use(sfp) && dxfer_len <= rsv_schp->bufflen)
1670			sg_link_reserve(sfp, srp, dxfer_len);
1671		else {
1672			res = sg_build_indirect(req_schp, sfp, dxfer_len);
1673			if (res)
1674				return res;
1675		}
1676
1677		md->pages = req_schp->pages;
1678		md->page_order = req_schp->page_order;
1679		md->nr_entries = req_schp->k_use_sg;
1680		md->offset = 0;
1681		md->null_mapped = hp->dxferp ? 0 : 1;
1682		if (dxfer_dir == SG_DXFER_TO_FROM_DEV)
1683			md->from_user = 1;
1684		else
1685			md->from_user = 0;
1686	}
1687
1688	if (iov_count) {
1689		int len, size = sizeof(struct sg_iovec) * iov_count;
1690		struct iovec *iov;
1691
1692		iov = memdup_user(hp->dxferp, size);
1693		if (IS_ERR(iov))
1694			return PTR_ERR(iov);
1695
1696		len = iov_length(iov, iov_count);
1697		if (hp->dxfer_len < len) {
1698			iov_count = iov_shorten(iov, iov_count, hp->dxfer_len);
1699			len = hp->dxfer_len;
1700		}
1701
1702		res = blk_rq_map_user_iov(q, rq, md, (struct sg_iovec *)iov,
1703					  iov_count,
1704					  len, GFP_ATOMIC);
1705		kfree(iov);
1706	} else
1707		res = blk_rq_map_user(q, rq, md, hp->dxferp,
1708				      hp->dxfer_len, GFP_ATOMIC);
1709
1710	if (!res) {
1711		srp->bio = rq->bio;
1712
1713		if (!md) {
1714			req_schp->dio_in_use = 1;
1715			hp->info |= SG_INFO_DIRECT_IO;
1716		}
1717	}
1718	return res;
1719}
1720
1721static int sg_finish_rem_req(Sg_request * srp)
 
1722{
1723	int ret = 0;
1724
1725	Sg_fd *sfp = srp->parentfp;
1726	Sg_scatter_hold *req_schp = &srp->data;
1727
1728	SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n", (int) srp->res_used));
 
 
 
 
 
1729	if (srp->rq) {
1730		if (srp->bio)
1731			ret = blk_rq_unmap_user(srp->bio);
1732
1733		blk_put_request(srp->rq);
1734	}
1735
1736	if (srp->res_used)
1737		sg_unlink_reserve(sfp, srp);
1738	else
1739		sg_remove_scat(req_schp);
1740
1741	sg_remove_request(sfp, srp);
1742
1743	return ret;
1744}
1745
1746static int
1747sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)
1748{
1749	int sg_bufflen = tablesize * sizeof(struct page *);
1750	gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;
1751
1752	schp->pages = kzalloc(sg_bufflen, gfp_flags);
1753	if (!schp->pages)
1754		return -ENOMEM;
1755	schp->sglist_len = sg_bufflen;
1756	return tablesize;	/* number of scat_gath elements allocated */
1757}
1758
1759static int
1760sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
1761{
1762	int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;
1763	int sg_tablesize = sfp->parentdp->sg_tablesize;
1764	int blk_size = buff_size, order;
1765	gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN;
1766
1767	if (blk_size < 0)
1768		return -EFAULT;
1769	if (0 == blk_size)
1770		++blk_size;	/* don't know why */
1771	/* round request up to next highest SG_SECTOR_SZ byte boundary */
1772	blk_size = ALIGN(blk_size, SG_SECTOR_SZ);
1773	SCSI_LOG_TIMEOUT(4, printk("sg_build_indirect: buff_size=%d, blk_size=%d\n",
1774				   buff_size, blk_size));
 
1775
1776	/* N.B. ret_sz carried into this block ... */
1777	mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);
1778	if (mx_sc_elems < 0)
1779		return mx_sc_elems;	/* most likely -ENOMEM */
1780
1781	num = scatter_elem_sz;
1782	if (unlikely(num != scatter_elem_sz_prev)) {
1783		if (num < PAGE_SIZE) {
1784			scatter_elem_sz = PAGE_SIZE;
1785			scatter_elem_sz_prev = PAGE_SIZE;
1786		} else
1787			scatter_elem_sz_prev = num;
1788	}
1789
1790	if (sfp->low_dma)
1791		gfp_mask |= GFP_DMA;
1792
1793	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
1794		gfp_mask |= __GFP_ZERO;
1795
1796	order = get_order(num);
1797retry:
1798	ret_sz = 1 << (PAGE_SHIFT + order);
1799
1800	for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;
1801	     k++, rem_sz -= ret_sz) {
1802
1803		num = (rem_sz > scatter_elem_sz_prev) ?
1804			scatter_elem_sz_prev : rem_sz;
1805
1806		schp->pages[k] = alloc_pages(gfp_mask, order);
1807		if (!schp->pages[k])
1808			goto out;
1809
1810		if (num == scatter_elem_sz_prev) {
1811			if (unlikely(ret_sz > scatter_elem_sz_prev)) {
1812				scatter_elem_sz = ret_sz;
1813				scatter_elem_sz_prev = ret_sz;
1814			}
1815		}
1816
1817		SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, "
1818				 "ret_sz=%d\n", k, num, ret_sz));
 
1819	}		/* end of for loop */
1820
1821	schp->page_order = order;
1822	schp->k_use_sg = k;
1823	SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_use_sg=%d, "
1824			 "rem_sz=%d\n", k, rem_sz));
 
1825
1826	schp->bufflen = blk_size;
1827	if (rem_sz > 0)	/* must have failed */
1828		return -ENOMEM;
1829	return 0;
1830out:
1831	for (i = 0; i < k; i++)
1832		__free_pages(schp->pages[i], order);
1833
1834	if (--order >= 0)
1835		goto retry;
1836
1837	return -ENOMEM;
1838}
1839
1840static void
1841sg_remove_scat(Sg_scatter_hold * schp)
1842{
1843	SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));
 
1844	if (schp->pages && schp->sglist_len > 0) {
1845		if (!schp->dio_in_use) {
1846			int k;
1847
1848			for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1849				SCSI_LOG_TIMEOUT(5, printk(
1850				    "sg_remove_scat: k=%d, pg=0x%p\n",
1851				    k, schp->pages[k]));
 
1852				__free_pages(schp->pages[k], schp->page_order);
1853			}
1854
1855			kfree(schp->pages);
1856		}
1857	}
1858	memset(schp, 0, sizeof (*schp));
1859}
1860
1861static int
1862sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
1863{
1864	Sg_scatter_hold *schp = &srp->data;
1865	int k, num;
1866
1867	SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n",
1868				   num_read_xfer));
 
1869	if ((!outp) || (num_read_xfer <= 0))
1870		return 0;
1871
1872	num = 1 << (PAGE_SHIFT + schp->page_order);
1873	for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {
1874		if (num > num_read_xfer) {
1875			if (__copy_to_user(outp, page_address(schp->pages[k]),
1876					   num_read_xfer))
1877				return -EFAULT;
1878			break;
1879		} else {
1880			if (__copy_to_user(outp, page_address(schp->pages[k]),
1881					   num))
1882				return -EFAULT;
1883			num_read_xfer -= num;
1884			if (num_read_xfer <= 0)
1885				break;
1886			outp += num;
1887		}
1888	}
1889
1890	return 0;
1891}
1892
1893static void
1894sg_build_reserve(Sg_fd * sfp, int req_size)
1895{
1896	Sg_scatter_hold *schp = &sfp->reserve;
1897
1898	SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
 
1899	do {
1900		if (req_size < PAGE_SIZE)
1901			req_size = PAGE_SIZE;
1902		if (0 == sg_build_indirect(schp, sfp, req_size))
1903			return;
1904		else
1905			sg_remove_scat(schp);
1906		req_size >>= 1;	/* divide by 2 */
1907	} while (req_size > (PAGE_SIZE / 2));
1908}
1909
1910static void
1911sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
1912{
1913	Sg_scatter_hold *req_schp = &srp->data;
1914	Sg_scatter_hold *rsv_schp = &sfp->reserve;
1915	int k, num, rem;
1916
1917	srp->res_used = 1;
1918	SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
 
1919	rem = size;
1920
1921	num = 1 << (PAGE_SHIFT + rsv_schp->page_order);
1922	for (k = 0; k < rsv_schp->k_use_sg; k++) {
1923		if (rem <= num) {
1924			req_schp->k_use_sg = k + 1;
1925			req_schp->sglist_len = rsv_schp->sglist_len;
1926			req_schp->pages = rsv_schp->pages;
1927
1928			req_schp->bufflen = size;
1929			req_schp->page_order = rsv_schp->page_order;
1930			break;
1931		} else
1932			rem -= num;
1933	}
1934
1935	if (k >= rsv_schp->k_use_sg)
1936		SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
 
1937}
1938
1939static void
1940sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
1941{
1942	Sg_scatter_hold *req_schp = &srp->data;
1943
1944	SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->k_use_sg=%d\n",
1945				   (int) req_schp->k_use_sg));
 
1946	req_schp->k_use_sg = 0;
1947	req_schp->bufflen = 0;
1948	req_schp->pages = NULL;
1949	req_schp->page_order = 0;
1950	req_schp->sglist_len = 0;
1951	sfp->save_scat_len = 0;
1952	srp->res_used = 0;
1953}
1954
1955static Sg_request *
1956sg_get_rq_mark(Sg_fd * sfp, int pack_id)
1957{
1958	Sg_request *resp;
1959	unsigned long iflags;
1960
1961	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1962	for (resp = sfp->headrp; resp; resp = resp->nextrp) {
1963		/* look for requests that are ready + not SG_IO owned */
1964		if ((1 == resp->done) && (!resp->sg_io_owned) &&
1965		    ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {
1966			resp->done = 2;	/* guard against other readers */
1967			break;
1968		}
1969	}
1970	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
1971	return resp;
1972}
1973
1974/* always adds to end of list */
1975static Sg_request *
1976sg_add_request(Sg_fd * sfp)
1977{
1978	int k;
1979	unsigned long iflags;
1980	Sg_request *resp;
1981	Sg_request *rp = sfp->req_arr;
1982
1983	write_lock_irqsave(&sfp->rq_list_lock, iflags);
1984	resp = sfp->headrp;
1985	if (!resp) {
1986		memset(rp, 0, sizeof (Sg_request));
1987		rp->parentfp = sfp;
1988		resp = rp;
1989		sfp->headrp = resp;
1990	} else {
1991		if (0 == sfp->cmd_q)
1992			resp = NULL;	/* command queuing disallowed */
1993		else {
1994			for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {
1995				if (!rp->parentfp)
1996					break;
1997			}
1998			if (k < SG_MAX_QUEUE) {
1999				memset(rp, 0, sizeof (Sg_request));
2000				rp->parentfp = sfp;
2001				while (resp->nextrp)
2002					resp = resp->nextrp;
2003				resp->nextrp = rp;
2004				resp = rp;
2005			} else
2006				resp = NULL;
2007		}
2008	}
2009	if (resp) {
2010		resp->nextrp = NULL;
2011		resp->header.duration = jiffies_to_msecs(jiffies);
2012	}
2013	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2014	return resp;
2015}
2016
2017/* Return of 1 for found; 0 for not found */
2018static int
2019sg_remove_request(Sg_fd * sfp, Sg_request * srp)
2020{
2021	Sg_request *prev_rp;
2022	Sg_request *rp;
2023	unsigned long iflags;
2024	int res = 0;
2025
2026	if ((!sfp) || (!srp) || (!sfp->headrp))
2027		return res;
2028	write_lock_irqsave(&sfp->rq_list_lock, iflags);
2029	prev_rp = sfp->headrp;
2030	if (srp == prev_rp) {
2031		sfp->headrp = prev_rp->nextrp;
2032		prev_rp->parentfp = NULL;
2033		res = 1;
2034	} else {
2035		while ((rp = prev_rp->nextrp)) {
2036			if (srp == rp) {
2037				prev_rp->nextrp = rp->nextrp;
2038				rp->parentfp = NULL;
2039				res = 1;
2040				break;
2041			}
2042			prev_rp = rp;
2043		}
2044	}
2045	write_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2046	return res;
2047}
2048
2049static Sg_fd *
2050sg_add_sfp(Sg_device * sdp, int dev)
2051{
2052	Sg_fd *sfp;
2053	unsigned long iflags;
2054	int bufflen;
2055
2056	sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);
2057	if (!sfp)
2058		return NULL;
2059
2060	init_waitqueue_head(&sfp->read_wait);
2061	rwlock_init(&sfp->rq_list_lock);
2062
2063	kref_init(&sfp->f_ref);
2064	sfp->timeout = SG_DEFAULT_TIMEOUT;
2065	sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
2066	sfp->force_packid = SG_DEF_FORCE_PACK_ID;
2067	sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
2068	    sdp->device->host->unchecked_isa_dma : 1;
2069	sfp->cmd_q = SG_DEF_COMMAND_Q;
2070	sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;
2071	sfp->parentdp = sdp;
2072	write_lock_irqsave(&sg_index_lock, iflags);
 
 
 
 
2073	list_add_tail(&sfp->sfd_siblings, &sdp->sfds);
2074	write_unlock_irqrestore(&sg_index_lock, iflags);
2075	SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
 
2076	if (unlikely(sg_big_buff != def_reserved_size))
2077		sg_big_buff = def_reserved_size;
2078
2079	bufflen = min_t(int, sg_big_buff,
2080			queue_max_sectors(sdp->device->request_queue) * 512);
2081	sg_build_reserve(sfp, bufflen);
2082	SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp:   bufflen=%d, k_use_sg=%d\n",
2083			   sfp->reserve.bufflen, sfp->reserve.k_use_sg));
 
 
2084
2085	kref_get(&sdp->d_ref);
2086	__module_get(THIS_MODULE);
2087	return sfp;
2088}
2089
2090static void sg_remove_sfp_usercontext(struct work_struct *work)
 
2091{
2092	struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);
2093	struct sg_device *sdp = sfp->parentdp;
2094
2095	/* Cleanup any responses which were never read(). */
2096	while (sfp->headrp)
2097		sg_finish_rem_req(sfp->headrp);
2098
2099	if (sfp->reserve.bufflen > 0) {
2100		SCSI_LOG_TIMEOUT(6,
2101			printk("sg_remove_sfp:    bufflen=%d, k_use_sg=%d\n",
2102				(int) sfp->reserve.bufflen,
2103				(int) sfp->reserve.k_use_sg));
2104		sg_remove_scat(&sfp->reserve);
2105	}
2106
2107	SCSI_LOG_TIMEOUT(6,
2108		printk("sg_remove_sfp: %s, sfp=0x%p\n",
2109			sdp->disk->disk_name,
2110			sfp));
2111	kfree(sfp);
2112
2113	scsi_device_put(sdp->device);
2114	sg_put_dev(sdp);
2115	module_put(THIS_MODULE);
2116}
2117
2118static void sg_remove_sfp(struct kref *kref)
 
2119{
2120	struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);
2121	struct sg_device *sdp = sfp->parentdp;
2122	unsigned long iflags;
2123
2124	write_lock_irqsave(&sg_index_lock, iflags);
2125	list_del(&sfp->sfd_siblings);
2126	write_unlock_irqrestore(&sg_index_lock, iflags);
2127	wake_up_interruptible(&sdp->o_excl_wait);
2128
2129	INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);
2130	schedule_work(&sfp->ew.work);
2131}
2132
2133static int
2134sg_res_in_use(Sg_fd * sfp)
2135{
2136	const Sg_request *srp;
2137	unsigned long iflags;
2138
2139	read_lock_irqsave(&sfp->rq_list_lock, iflags);
2140	for (srp = sfp->headrp; srp; srp = srp->nextrp)
2141		if (srp->res_used)
2142			break;
2143	read_unlock_irqrestore(&sfp->rq_list_lock, iflags);
2144	return srp ? 1 : 0;
2145}
2146
2147#ifdef CONFIG_SCSI_PROC_FS
2148static int
2149sg_idr_max_id(int id, void *p, void *data)
2150{
2151	int *k = data;
2152
2153	if (*k < id)
2154		*k = id;
2155
2156	return 0;
2157}
2158
2159static int
2160sg_last_dev(void)
2161{
2162	int k = -1;
2163	unsigned long iflags;
2164
2165	read_lock_irqsave(&sg_index_lock, iflags);
2166	idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
2167	read_unlock_irqrestore(&sg_index_lock, iflags);
2168	return k + 1;		/* origin 1 */
2169}
2170#endif
2171
2172/* must be called with sg_index_lock held */
2173static Sg_device *sg_lookup_dev(int dev)
2174{
2175	return idr_find(&sg_index_idr, dev);
2176}
2177
2178static Sg_device *sg_get_dev(int dev)
 
2179{
2180	struct sg_device *sdp;
2181	unsigned long flags;
2182
2183	read_lock_irqsave(&sg_index_lock, flags);
2184	sdp = sg_lookup_dev(dev);
2185	if (!sdp)
2186		sdp = ERR_PTR(-ENXIO);
2187	else if (sdp->detached) {
2188		/* If sdp->detached, then the refcount may already be 0, in
2189		 * which case it would be a bug to do kref_get().
2190		 */
2191		sdp = ERR_PTR(-ENODEV);
2192	} else
2193		kref_get(&sdp->d_ref);
2194	read_unlock_irqrestore(&sg_index_lock, flags);
2195
2196	return sdp;
2197}
2198
2199static void sg_put_dev(struct sg_device *sdp)
2200{
2201	kref_put(&sdp->d_ref, sg_device_destroy);
2202}
2203
2204#ifdef CONFIG_SCSI_PROC_FS
2205
2206static struct proc_dir_entry *sg_proc_sgp = NULL;
2207
2208static char sg_proc_sg_dirname[] = "scsi/sg";
2209
2210static int sg_proc_seq_show_int(struct seq_file *s, void *v);
2211
2212static int sg_proc_single_open_adio(struct inode *inode, struct file *file);
2213static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,
2214			          size_t count, loff_t *off);
2215static const struct file_operations adio_fops = {
2216	.owner = THIS_MODULE,
2217	.open = sg_proc_single_open_adio,
2218	.read = seq_read,
2219	.llseek = seq_lseek,
2220	.write = sg_proc_write_adio,
2221	.release = single_release,
2222};
2223
2224static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);
2225static ssize_t sg_proc_write_dressz(struct file *filp, 
2226		const char __user *buffer, size_t count, loff_t *off);
2227static const struct file_operations dressz_fops = {
2228	.owner = THIS_MODULE,
2229	.open = sg_proc_single_open_dressz,
2230	.read = seq_read,
2231	.llseek = seq_lseek,
2232	.write = sg_proc_write_dressz,
2233	.release = single_release,
2234};
2235
2236static int sg_proc_seq_show_version(struct seq_file *s, void *v);
2237static int sg_proc_single_open_version(struct inode *inode, struct file *file);
2238static const struct file_operations version_fops = {
2239	.owner = THIS_MODULE,
2240	.open = sg_proc_single_open_version,
2241	.read = seq_read,
2242	.llseek = seq_lseek,
2243	.release = single_release,
2244};
2245
2246static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);
2247static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file);
2248static const struct file_operations devhdr_fops = {
2249	.owner = THIS_MODULE,
2250	.open = sg_proc_single_open_devhdr,
2251	.read = seq_read,
2252	.llseek = seq_lseek,
2253	.release = single_release,
2254};
2255
2256static int sg_proc_seq_show_dev(struct seq_file *s, void *v);
2257static int sg_proc_open_dev(struct inode *inode, struct file *file);
2258static void * dev_seq_start(struct seq_file *s, loff_t *pos);
2259static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);
2260static void dev_seq_stop(struct seq_file *s, void *v);
2261static const struct file_operations dev_fops = {
2262	.owner = THIS_MODULE,
2263	.open = sg_proc_open_dev,
2264	.read = seq_read,
2265	.llseek = seq_lseek,
2266	.release = seq_release,
2267};
2268static const struct seq_operations dev_seq_ops = {
2269	.start = dev_seq_start,
2270	.next  = dev_seq_next,
2271	.stop  = dev_seq_stop,
2272	.show  = sg_proc_seq_show_dev,
2273};
2274
2275static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);
2276static int sg_proc_open_devstrs(struct inode *inode, struct file *file);
2277static const struct file_operations devstrs_fops = {
2278	.owner = THIS_MODULE,
2279	.open = sg_proc_open_devstrs,
2280	.read = seq_read,
2281	.llseek = seq_lseek,
2282	.release = seq_release,
2283};
2284static const struct seq_operations devstrs_seq_ops = {
2285	.start = dev_seq_start,
2286	.next  = dev_seq_next,
2287	.stop  = dev_seq_stop,
2288	.show  = sg_proc_seq_show_devstrs,
2289};
2290
2291static int sg_proc_seq_show_debug(struct seq_file *s, void *v);
2292static int sg_proc_open_debug(struct inode *inode, struct file *file);
2293static const struct file_operations debug_fops = {
2294	.owner = THIS_MODULE,
2295	.open = sg_proc_open_debug,
2296	.read = seq_read,
2297	.llseek = seq_lseek,
2298	.release = seq_release,
2299};
2300static const struct seq_operations debug_seq_ops = {
2301	.start = dev_seq_start,
2302	.next  = dev_seq_next,
2303	.stop  = dev_seq_stop,
2304	.show  = sg_proc_seq_show_debug,
2305};
2306
2307
2308struct sg_proc_leaf {
2309	const char * name;
2310	const struct file_operations * fops;
2311};
2312
2313static struct sg_proc_leaf sg_proc_leaf_arr[] = {
2314	{"allow_dio", &adio_fops},
2315	{"debug", &debug_fops},
2316	{"def_reserved_size", &dressz_fops},
2317	{"device_hdr", &devhdr_fops},
2318	{"devices", &dev_fops},
2319	{"device_strs", &devstrs_fops},
2320	{"version", &version_fops}
2321};
2322
2323static int
2324sg_proc_init(void)
2325{
2326	int k, mask;
2327	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2328	struct sg_proc_leaf * leaf;
2329
2330	sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL);
2331	if (!sg_proc_sgp)
2332		return 1;
2333	for (k = 0; k < num_leaves; ++k) {
2334		leaf = &sg_proc_leaf_arr[k];
2335		mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO;
2336		proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops);
2337	}
2338	return 0;
2339}
2340
2341static void
2342sg_proc_cleanup(void)
2343{
2344	int k;
2345	int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr);
2346
2347	if (!sg_proc_sgp)
2348		return;
2349	for (k = 0; k < num_leaves; ++k)
2350		remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp);
2351	remove_proc_entry(sg_proc_sg_dirname, NULL);
2352}
2353
2354
2355static int sg_proc_seq_show_int(struct seq_file *s, void *v)
2356{
2357	seq_printf(s, "%d\n", *((int *)s->private));
2358	return 0;
2359}
2360
2361static int sg_proc_single_open_adio(struct inode *inode, struct file *file)
2362{
2363	return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);
2364}
2365
2366static ssize_t 
2367sg_proc_write_adio(struct file *filp, const char __user *buffer,
2368		   size_t count, loff_t *off)
2369{
2370	int num;
2371	char buff[11];
2372
2373	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2374		return -EACCES;
2375	num = (count < 10) ? count : 10;
2376	if (copy_from_user(buff, buffer, num))
2377		return -EFAULT;
2378	buff[num] = '\0';
2379	sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0;
2380	return count;
2381}
2382
2383static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)
2384{
2385	return single_open(file, sg_proc_seq_show_int, &sg_big_buff);
2386}
2387
2388static ssize_t 
2389sg_proc_write_dressz(struct file *filp, const char __user *buffer,
2390		     size_t count, loff_t *off)
2391{
2392	int num;
2393	unsigned long k = ULONG_MAX;
2394	char buff[11];
2395
2396	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
2397		return -EACCES;
2398	num = (count < 10) ? count : 10;
2399	if (copy_from_user(buff, buffer, num))
2400		return -EFAULT;
2401	buff[num] = '\0';
2402	k = simple_strtoul(buff, NULL, 10);
2403	if (k <= 1048576) {	/* limit "big buff" to 1 MB */
2404		sg_big_buff = k;
2405		return count;
2406	}
2407	return -ERANGE;
2408}
2409
2410static int sg_proc_seq_show_version(struct seq_file *s, void *v)
2411{
2412	seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,
2413		   sg_version_date);
2414	return 0;
2415}
2416
2417static int sg_proc_single_open_version(struct inode *inode, struct file *file)
2418{
2419	return single_open(file, sg_proc_seq_show_version, NULL);
2420}
2421
2422static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)
2423{
2424	seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t"
2425		   "online\n");
2426	return 0;
2427}
2428
2429static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file)
2430{
2431	return single_open(file, sg_proc_seq_show_devhdr, NULL);
2432}
2433
2434struct sg_proc_deviter {
2435	loff_t	index;
2436	size_t	max;
2437};
2438
2439static void * dev_seq_start(struct seq_file *s, loff_t *pos)
2440{
2441	struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);
2442
2443	s->private = it;
2444	if (! it)
2445		return NULL;
2446
2447	it->index = *pos;
2448	it->max = sg_last_dev();
2449	if (it->index >= it->max)
2450		return NULL;
2451	return it;
2452}
2453
2454static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)
2455{
2456	struct sg_proc_deviter * it = s->private;
2457
2458	*pos = ++it->index;
2459	return (it->index < it->max) ? it : NULL;
2460}
2461
2462static void dev_seq_stop(struct seq_file *s, void *v)
2463{
2464	kfree(s->private);
2465}
2466
2467static int sg_proc_open_dev(struct inode *inode, struct file *file)
2468{
2469        return seq_open(file, &dev_seq_ops);
2470}
2471
2472static int sg_proc_seq_show_dev(struct seq_file *s, void *v)
2473{
2474	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2475	Sg_device *sdp;
2476	struct scsi_device *scsidp;
2477	unsigned long iflags;
2478
2479	read_lock_irqsave(&sg_index_lock, iflags);
2480	sdp = it ? sg_lookup_dev(it->index) : NULL;
2481	if (sdp && (scsidp = sdp->device) && (!sdp->detached))
2482		seq_printf(s, "%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
 
 
 
 
2483			      scsidp->host->host_no, scsidp->channel,
2484			      scsidp->id, scsidp->lun, (int) scsidp->type,
2485			      1,
2486			      (int) scsidp->queue_depth,
2487			      (int) scsidp->device_busy,
2488			      (int) scsi_device_online(scsidp));
2489	else
2490		seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
2491	read_unlock_irqrestore(&sg_index_lock, iflags);
2492	return 0;
2493}
2494
2495static int sg_proc_open_devstrs(struct inode *inode, struct file *file)
2496{
2497        return seq_open(file, &devstrs_seq_ops);
2498}
2499
2500static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)
2501{
2502	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2503	Sg_device *sdp;
2504	struct scsi_device *scsidp;
2505	unsigned long iflags;
2506
2507	read_lock_irqsave(&sg_index_lock, iflags);
2508	sdp = it ? sg_lookup_dev(it->index) : NULL;
2509	if (sdp && (scsidp = sdp->device) && (!sdp->detached))
 
2510		seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",
2511			   scsidp->vendor, scsidp->model, scsidp->rev);
2512	else
2513		seq_printf(s, "<no active device>\n");
2514	read_unlock_irqrestore(&sg_index_lock, iflags);
2515	return 0;
2516}
2517
2518/* must be called while holding sg_index_lock */
2519static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)
2520{
2521	int k, m, new_interface, blen, usg;
2522	Sg_request *srp;
2523	Sg_fd *fp;
2524	const sg_io_hdr_t *hp;
2525	const char * cp;
2526	unsigned int ms;
2527
2528	k = 0;
2529	list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {
2530		k++;
2531		read_lock(&fp->rq_list_lock); /* irqs already disabled */
2532		seq_printf(s, "   FD(%d): timeout=%dms bufflen=%d "
2533			   "(res)sgat=%d low_dma=%d\n", k,
2534			   jiffies_to_msecs(fp->timeout),
2535			   fp->reserve.bufflen,
2536			   (int) fp->reserve.k_use_sg,
2537			   (int) fp->low_dma);
2538		seq_printf(s, "   cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n",
2539			   (int) fp->cmd_q, (int) fp->force_packid,
2540			   (int) fp->keep_orphan, (int) fp->closed);
2541		for (m = 0, srp = fp->headrp;
2542				srp != NULL;
2543				++m, srp = srp->nextrp) {
2544			hp = &srp->header;
2545			new_interface = (hp->interface_id == '\0') ? 0 : 1;
2546			if (srp->res_used) {
2547				if (new_interface && 
2548				    (SG_FLAG_MMAP_IO & hp->flags))
2549					cp = "     mmap>> ";
2550				else
2551					cp = "     rb>> ";
2552			} else {
2553				if (SG_INFO_DIRECT_IO_MASK & hp->info)
2554					cp = "     dio>> ";
2555				else
2556					cp = "     ";
2557			}
2558			seq_printf(s, cp);
2559			blen = srp->data.bufflen;
2560			usg = srp->data.k_use_sg;
2561			seq_printf(s, srp->done ? 
2562				   ((1 == srp->done) ?  "rcv:" : "fin:")
2563				   : "act:");
2564			seq_printf(s, " id=%d blen=%d",
2565				   srp->header.pack_id, blen);
2566			if (srp->done)
2567				seq_printf(s, " dur=%d", hp->duration);
2568			else {
2569				ms = jiffies_to_msecs(jiffies);
2570				seq_printf(s, " t_o/elap=%d/%d",
2571					(new_interface ? hp->timeout :
2572						  jiffies_to_msecs(fp->timeout)),
2573					(ms > hp->duration ? ms - hp->duration : 0));
2574			}
2575			seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,
2576				   (int) srp->data.cmd_opcode);
2577		}
2578		if (0 == m)
2579			seq_printf(s, "     No requests active\n");
2580		read_unlock(&fp->rq_list_lock);
2581	}
2582}
2583
2584static int sg_proc_open_debug(struct inode *inode, struct file *file)
2585{
2586        return seq_open(file, &debug_seq_ops);
2587}
2588
2589static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
2590{
2591	struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;
2592	Sg_device *sdp;
2593	unsigned long iflags;
2594
2595	if (it && (0 == it->index)) {
2596		seq_printf(s, "max_active_device=%d(origin 1)\n",
2597			   (int)it->max);
2598		seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
2599	}
2600
2601	read_lock_irqsave(&sg_index_lock, iflags);
2602	sdp = it ? sg_lookup_dev(it->index) : NULL;
2603	if (sdp && !list_empty(&sdp->sfds)) {
2604		struct scsi_device *scsidp = sdp->device;
2605
 
2606		seq_printf(s, " >>> device=%s ", sdp->disk->disk_name);
2607		if (sdp->detached)
2608			seq_printf(s, "detached pending close ");
2609		else
2610			seq_printf
2611			    (s, "scsi%d chan=%d id=%d lun=%d   em=%d",
2612			     scsidp->host->host_no,
2613			     scsidp->channel, scsidp->id,
2614			     scsidp->lun,
2615			     scsidp->host->hostt->emulated);
2616		seq_printf(s, " sg_tablesize=%d excl=%d\n",
2617			   sdp->sg_tablesize, sdp->exclude);
 
 
2618		sg_proc_debug_helper(s, sdp);
2619	}
 
 
2620	read_unlock_irqrestore(&sg_index_lock, iflags);
2621	return 0;
2622}
2623
2624#endif				/* CONFIG_SCSI_PROC_FS */
2625
2626module_init(init_sg);
2627module_exit(exit_sg);